)^
+**
+** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
+** macro. ^The sqlite3_libversion() function returns a pointer to the
+** to the sqlite3_version[] string constant. The sqlite3_libversion()
+** function is provided for use in DLLs since DLL users usually do not have
+** direct access to string constants within the DLL. ^The
+** sqlite3_libversion_number() function returns an integer equal to
+** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns
+** a pointer to a string constant whose value is the same as the
+** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built
+** using an edited copy of [the amalgamation], then the last four characters
+** of the hash might be different from [SQLITE_SOURCE_ID].)^
+**
+** See also: [sqlite_version()] and [sqlite_source_id()].
+*/
+SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
+SQLITE_API const char *sqlite3_libversion(void);
+SQLITE_API const char *sqlite3_sourceid(void);
+SQLITE_API int sqlite3_libversion_number(void);
+
+/*
+** CAPI3REF: Run-Time Library Compilation Options Diagnostics
+**
+** ^The sqlite3_compileoption_used() function returns 0 or 1
+** indicating whether the specified option was defined at
+** compile time. ^The SQLITE_ prefix may be omitted from the
+** option name passed to sqlite3_compileoption_used().
+**
+** ^The sqlite3_compileoption_get() function allows iterating
+** over the list of options that were defined at compile time by
+** returning the N-th compile time option string. ^If N is out of range,
+** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
+** prefix is omitted from any strings returned by
+** sqlite3_compileoption_get().
+**
+** ^Support for the diagnostic functions sqlite3_compileoption_used()
+** and sqlite3_compileoption_get() may be omitted by specifying the
+** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
+**
+** See also: SQL functions [sqlite_compileoption_used()] and
+** [sqlite_compileoption_get()] and the [compile_options pragma].
+*/
+#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
+SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
+SQLITE_API const char *sqlite3_compileoption_get(int N);
+#endif
+
+/*
+** CAPI3REF: Test To See If The Library Is Threadsafe
+**
+** ^The sqlite3_threadsafe() function returns zero if and only if
+** SQLite was compiled with mutexing code omitted due to the
+** [SQLITE_THREADSAFE] compile-time option being set to 0.
+**
+** SQLite can be compiled with or without mutexes. When
+** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
+** are enabled and SQLite is threadsafe. When the
+** [SQLITE_THREADSAFE] macro is 0,
+** the mutexes are omitted. Without the mutexes, it is not safe
+** to use SQLite concurrently from more than one thread.
+**
+** Enabling mutexes incurs a measurable performance penalty.
+** So if speed is of utmost importance, it makes sense to disable
+** the mutexes. But for maximum safety, mutexes should be enabled.
+** ^The default behavior is for mutexes to be enabled.
+**
+** This interface can be used by an application to make sure that the
+** version of SQLite that it is linking against was compiled with
+** the desired setting of the [SQLITE_THREADSAFE] macro.
+**
+** This interface only reports on the compile-time mutex setting
+** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
+** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
+** can be fully or partially disabled using a call to [sqlite3_config()]
+** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
+** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the
+** sqlite3_threadsafe() function shows only the compile-time setting of
+** thread safety, not any run-time changes to that setting made by
+** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
+** is unchanged by calls to sqlite3_config().)^
+**
+** See the [threading mode] documentation for additional information.
+*/
+SQLITE_API int sqlite3_threadsafe(void);
+
+/*
+** CAPI3REF: Database Connection Handle
+** KEYWORDS: {database connection} {database connections}
+**
+** Each open SQLite database is represented by a pointer to an instance of
+** the opaque structure named "sqlite3". It is useful to think of an sqlite3
+** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
+** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
+** and [sqlite3_close_v2()] are its destructors. There are many other
+** interfaces (such as
+** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
+** [sqlite3_busy_timeout()] to name but three) that are methods on an
+** sqlite3 object.
+*/
+typedef struct sqlite3 sqlite3;
+
+/*
+** CAPI3REF: 64-Bit Integer Types
+** KEYWORDS: sqlite_int64 sqlite_uint64
+**
+** Because there is no cross-platform way to specify 64-bit integer types
+** SQLite includes typedefs for 64-bit signed and unsigned integers.
+**
+** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
+** The sqlite_int64 and sqlite_uint64 types are supported for backwards
+** compatibility only.
+**
+** ^The sqlite3_int64 and sqlite_int64 types can store integer values
+** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
+** sqlite3_uint64 and sqlite_uint64 types can store integer values
+** between 0 and +18446744073709551615 inclusive.
+*/
+#ifdef SQLITE_INT64_TYPE
+ typedef SQLITE_INT64_TYPE sqlite_int64;
+# ifdef SQLITE_UINT64_TYPE
+ typedef SQLITE_UINT64_TYPE sqlite_uint64;
+# else
+ typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
+# endif
+#elif defined(_MSC_VER) || defined(__BORLANDC__)
+ typedef __int64 sqlite_int64;
+ typedef unsigned __int64 sqlite_uint64;
+#else
+ typedef long long int sqlite_int64;
+ typedef unsigned long long int sqlite_uint64;
+#endif
+typedef sqlite_int64 sqlite3_int64;
+typedef sqlite_uint64 sqlite3_uint64;
+
+/*
+** If compiling for a processor that lacks floating point support,
+** substitute integer for floating-point.
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define double sqlite3_int64
+#endif
+
+/*
+** CAPI3REF: Closing A Database Connection
+** DESTRUCTOR: sqlite3
+**
+** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
+** for the [sqlite3] object.
+** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
+** the [sqlite3] object is successfully destroyed and all associated
+** resources are deallocated.
+**
+** ^If the database connection is associated with unfinalized prepared
+** statements or unfinished sqlite3_backup objects then sqlite3_close()
+** will leave the database connection open and return [SQLITE_BUSY].
+** ^If sqlite3_close_v2() is called with unfinalized prepared statements
+** and/or unfinished sqlite3_backups, then the database connection becomes
+** an unusable "zombie" which will automatically be deallocated when the
+** last prepared statement is finalized or the last sqlite3_backup is
+** finished. The sqlite3_close_v2() interface is intended for use with
+** host languages that are garbage collected, and where the order in which
+** destructors are called is arbitrary.
+**
+** Applications should [sqlite3_finalize | finalize] all [prepared statements],
+** [sqlite3_blob_close | close] all [BLOB handles], and
+** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
+** with the [sqlite3] object prior to attempting to close the object. ^If
+** sqlite3_close_v2() is called on a [database connection] that still has
+** outstanding [prepared statements], [BLOB handles], and/or
+** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
+** of resources is deferred until all [prepared statements], [BLOB handles],
+** and [sqlite3_backup] objects are also destroyed.
+**
+** ^If an [sqlite3] object is destroyed while a transaction is open,
+** the transaction is automatically rolled back.
+**
+** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
+** must be either a NULL
+** pointer or an [sqlite3] object pointer obtained
+** from [sqlite3_open()], [sqlite3_open16()], or
+** [sqlite3_open_v2()], and not previously closed.
+** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
+** argument is a harmless no-op.
+*/
+SQLITE_API int sqlite3_close(sqlite3*);
+SQLITE_API int sqlite3_close_v2(sqlite3*);
+
+/*
+** The type for a callback function.
+** This is legacy and deprecated. It is included for historical
+** compatibility and is not documented.
+*/
+typedef int (*sqlite3_callback)(void*,int,char**, char**);
+
+/*
+** CAPI3REF: One-Step Query Execution Interface
+** METHOD: sqlite3
+**
+** The sqlite3_exec() interface is a convenience wrapper around
+** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
+** that allows an application to run multiple statements of SQL
+** without having to use a lot of C code.
+**
+** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
+** semicolon-separate SQL statements passed into its 2nd argument,
+** in the context of the [database connection] passed in as its 1st
+** argument. ^If the callback function of the 3rd argument to
+** sqlite3_exec() is not NULL, then it is invoked for each result row
+** coming out of the evaluated SQL statements. ^The 4th argument to
+** sqlite3_exec() is relayed through to the 1st argument of each
+** callback invocation. ^If the callback pointer to sqlite3_exec()
+** is NULL, then no callback is ever invoked and result rows are
+** ignored.
+**
+** ^If an error occurs while evaluating the SQL statements passed into
+** sqlite3_exec(), then execution of the current statement stops and
+** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
+** is not NULL then any error message is written into memory obtained
+** from [sqlite3_malloc()] and passed back through the 5th parameter.
+** To avoid memory leaks, the application should invoke [sqlite3_free()]
+** on error message strings returned through the 5th parameter of
+** sqlite3_exec() after the error message string is no longer needed.
+** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
+** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
+** NULL before returning.
+**
+** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
+** routine returns SQLITE_ABORT without invoking the callback again and
+** without running any subsequent SQL statements.
+**
+** ^The 2nd argument to the sqlite3_exec() callback function is the
+** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
+** callback is an array of pointers to strings obtained as if from
+** [sqlite3_column_text()], one for each column. ^If an element of a
+** result row is NULL then the corresponding string pointer for the
+** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
+** sqlite3_exec() callback is an array of pointers to strings where each
+** entry represents the name of corresponding result column as obtained
+** from [sqlite3_column_name()].
+**
+** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
+** to an empty string, or a pointer that contains only whitespace and/or
+** SQL comments, then no SQL statements are evaluated and the database
+** is not changed.
+**
+** Restrictions:
+**
+**
+**
The application must ensure that the 1st parameter to sqlite3_exec()
+** is a valid and open [database connection].
+**
The application must not close the [database connection] specified by
+** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
+**
The application must not modify the SQL statement text passed into
+** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
+**
+*/
+SQLITE_API int sqlite3_exec(
+ sqlite3*, /* An open database */
+ const char *sql, /* SQL to be evaluated */
+ int (*callback)(void*,int,char**,char**), /* Callback function */
+ void *, /* 1st argument to callback */
+ char **errmsg /* Error msg written here */
+);
+
+/*
+** CAPI3REF: Result Codes
+** KEYWORDS: {result code definitions}
+**
+** Many SQLite functions return an integer result code from the set shown
+** here in order to indicate success or failure.
+**
+** New error codes may be added in future versions of SQLite.
+**
+** See also: [extended result code definitions]
+*/
+#define SQLITE_OK 0 /* Successful result */
+/* beginning-of-error-codes */
+#define SQLITE_ERROR 1 /* Generic error */
+#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
+#define SQLITE_PERM 3 /* Access permission denied */
+#define SQLITE_ABORT 4 /* Callback routine requested an abort */
+#define SQLITE_BUSY 5 /* The database file is locked */
+#define SQLITE_LOCKED 6 /* A table in the database is locked */
+#define SQLITE_NOMEM 7 /* A malloc() failed */
+#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
+#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
+#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
+#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
+#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
+#define SQLITE_FULL 13 /* Insertion failed because database is full */
+#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
+#define SQLITE_PROTOCOL 15 /* Database lock protocol error */
+#define SQLITE_EMPTY 16 /* Internal use only */
+#define SQLITE_SCHEMA 17 /* The database schema changed */
+#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
+#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
+#define SQLITE_MISMATCH 20 /* Data type mismatch */
+#define SQLITE_MISUSE 21 /* Library used incorrectly */
+#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
+#define SQLITE_AUTH 23 /* Authorization denied */
+#define SQLITE_FORMAT 24 /* Not used */
+#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
+#define SQLITE_NOTADB 26 /* File opened that is not a database file */
+#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
+#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
+#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
+#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
+/* end-of-error-codes */
+
+/*
+** CAPI3REF: Extended Result Codes
+** KEYWORDS: {extended result code definitions}
+**
+** In its default configuration, SQLite API routines return one of 30 integer
+** [result codes]. However, experience has shown that many of
+** these result codes are too coarse-grained. They do not provide as
+** much information about problems as programmers might like. In an effort to
+** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
+** and later) include
+** support for additional result codes that provide more detailed information
+** about errors. These [extended result codes] are enabled or disabled
+** on a per database connection basis using the
+** [sqlite3_extended_result_codes()] API. Or, the extended code for
+** the most recent error can be obtained using
+** [sqlite3_extended_errcode()].
+*/
+#define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8))
+#define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8))
+#define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8))
+#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
+#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
+#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
+#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
+#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
+#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
+#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
+#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
+#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
+#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
+#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
+#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
+#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
+#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
+#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
+#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
+#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
+#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
+#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
+#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
+#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
+#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
+#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
+#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
+#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
+#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
+#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8))
+#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8))
+#define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8))
+#define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8))
+#define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8))
+#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
+#define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8))
+#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
+#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
+#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
+#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
+#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
+#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
+#define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
+#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
+#define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8))
+#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
+#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
+#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
+#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
+#define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8))
+#define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8))
+#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
+#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
+#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
+#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
+#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
+#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
+#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
+#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
+#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
+#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
+#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
+#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
+#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
+#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
+#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8))
+#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8))
+
+/*
+** CAPI3REF: Flags For File Open Operations
+**
+** These bit values are intended for use in the
+** 3rd parameter to the [sqlite3_open_v2()] interface and
+** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
+*/
+#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
+#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
+#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
+#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
+#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
+#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
+#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
+#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
+#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
+#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
+#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
+
+/* Reserved: 0x00F00000 */
+
+/*
+** CAPI3REF: Device Characteristics
+**
+** The xDeviceCharacteristics method of the [sqlite3_io_methods]
+** object returns an integer which is a vector of these
+** bit values expressing I/O characteristics of the mass storage
+** device that holds the file that the [sqlite3_io_methods]
+** refers to.
+**
+** The SQLITE_IOCAP_ATOMIC property means that all writes of
+** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
+** mean that writes of blocks that are nnn bytes in size and
+** are aligned to an address which is an integer multiple of
+** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
+** that when data is appended to a file, the data is appended
+** first then the size of the file is extended, never the other
+** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
+** information is written to disk in the same order as calls
+** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
+** after reboot following a crash or power loss, the only bytes in a
+** file that were written at the application level might have changed
+** and that adjacent bytes, even bytes within the same sector are
+** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
+** flag indicates that a file cannot be deleted when open. The
+** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
+** read-only media and cannot be changed even by processes with
+** elevated privileges.
+**
+** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
+** filesystem supports doing multiple write operations atomically when those
+** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
+** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
+*/
+#define SQLITE_IOCAP_ATOMIC 0x00000001
+#define SQLITE_IOCAP_ATOMIC512 0x00000002
+#define SQLITE_IOCAP_ATOMIC1K 0x00000004
+#define SQLITE_IOCAP_ATOMIC2K 0x00000008
+#define SQLITE_IOCAP_ATOMIC4K 0x00000010
+#define SQLITE_IOCAP_ATOMIC8K 0x00000020
+#define SQLITE_IOCAP_ATOMIC16K 0x00000040
+#define SQLITE_IOCAP_ATOMIC32K 0x00000080
+#define SQLITE_IOCAP_ATOMIC64K 0x00000100
+#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
+#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
+#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
+#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
+#define SQLITE_IOCAP_IMMUTABLE 0x00002000
+#define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000
+
+/*
+** CAPI3REF: File Locking Levels
+**
+** SQLite uses one of these integer values as the second
+** argument to calls it makes to the xLock() and xUnlock() methods
+** of an [sqlite3_io_methods] object.
+*/
+#define SQLITE_LOCK_NONE 0
+#define SQLITE_LOCK_SHARED 1
+#define SQLITE_LOCK_RESERVED 2
+#define SQLITE_LOCK_PENDING 3
+#define SQLITE_LOCK_EXCLUSIVE 4
+
+/*
+** CAPI3REF: Synchronization Type Flags
+**
+** When SQLite invokes the xSync() method of an
+** [sqlite3_io_methods] object it uses a combination of
+** these integer values as the second argument.
+**
+** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
+** sync operation only needs to flush data to mass storage. Inode
+** information need not be flushed. If the lower four bits of the flag
+** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
+** If the lower four bits equal SQLITE_SYNC_FULL, that means
+** to use Mac OS X style fullsync instead of fsync().
+**
+** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
+** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
+** settings. The [synchronous pragma] determines when calls to the
+** xSync VFS method occur and applies uniformly across all platforms.
+** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
+** energetic or rigorous or forceful the sync operations are and
+** only make a difference on Mac OSX for the default SQLite code.
+** (Third-party VFS implementations might also make the distinction
+** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
+** operating systems natively supported by SQLite, only Mac OSX
+** cares about the difference.)
+*/
+#define SQLITE_SYNC_NORMAL 0x00002
+#define SQLITE_SYNC_FULL 0x00003
+#define SQLITE_SYNC_DATAONLY 0x00010
+
+/*
+** CAPI3REF: OS Interface Open File Handle
+**
+** An [sqlite3_file] object represents an open file in the
+** [sqlite3_vfs | OS interface layer]. Individual OS interface
+** implementations will
+** want to subclass this object by appending additional fields
+** for their own use. The pMethods entry is a pointer to an
+** [sqlite3_io_methods] object that defines methods for performing
+** I/O operations on the open file.
+*/
+typedef struct sqlite3_file sqlite3_file;
+struct sqlite3_file {
+ const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
+};
+
+/*
+** CAPI3REF: OS Interface File Virtual Methods Object
+**
+** Every file opened by the [sqlite3_vfs.xOpen] method populates an
+** [sqlite3_file] object (or, more commonly, a subclass of the
+** [sqlite3_file] object) with a pointer to an instance of this object.
+** This object defines the methods used to perform various operations
+** against the open file represented by the [sqlite3_file] object.
+**
+** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
+** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
+** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
+** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
+** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
+** to NULL.
+**
+** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
+** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
+** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
+** flag may be ORed in to indicate that only the data of the file
+** and not its inode needs to be synced.
+**
+** The integer values to xLock() and xUnlock() are one of
+**
+**
[SQLITE_LOCK_NONE],
+**
[SQLITE_LOCK_SHARED],
+**
[SQLITE_LOCK_RESERVED],
+**
[SQLITE_LOCK_PENDING], or
+**
[SQLITE_LOCK_EXCLUSIVE].
+**
+** xLock() increases the lock. xUnlock() decreases the lock.
+** The xCheckReservedLock() method checks whether any database connection,
+** either in this process or in some other process, is holding a RESERVED,
+** PENDING, or EXCLUSIVE lock on the file. It returns true
+** if such a lock exists and false otherwise.
+**
+** The xFileControl() method is a generic interface that allows custom
+** VFS implementations to directly control an open file using the
+** [sqlite3_file_control()] interface. The second "op" argument is an
+** integer opcode. The third argument is a generic pointer intended to
+** point to a structure that may contain arguments or space in which to
+** write return values. Potential uses for xFileControl() might be
+** functions to enable blocking locks with timeouts, to change the
+** locking strategy (for example to use dot-file locks), to inquire
+** about the status of a lock, or to break stale locks. The SQLite
+** core reserves all opcodes less than 100 for its own use.
+** A [file control opcodes | list of opcodes] less than 100 is available.
+** Applications that define a custom xFileControl method should use opcodes
+** greater than 100 to avoid conflicts. VFS implementations should
+** return [SQLITE_NOTFOUND] for file control opcodes that they do not
+** recognize.
+**
+** The xSectorSize() method returns the sector size of the
+** device that underlies the file. The sector size is the
+** minimum write that can be performed without disturbing
+** other bytes in the file. The xDeviceCharacteristics()
+** method returns a bit vector describing behaviors of the
+** underlying device:
+**
+**
+**
[SQLITE_IOCAP_ATOMIC]
+**
[SQLITE_IOCAP_ATOMIC512]
+**
[SQLITE_IOCAP_ATOMIC1K]
+**
[SQLITE_IOCAP_ATOMIC2K]
+**
[SQLITE_IOCAP_ATOMIC4K]
+**
[SQLITE_IOCAP_ATOMIC8K]
+**
[SQLITE_IOCAP_ATOMIC16K]
+**
[SQLITE_IOCAP_ATOMIC32K]
+**
[SQLITE_IOCAP_ATOMIC64K]
+**
[SQLITE_IOCAP_SAFE_APPEND]
+**
[SQLITE_IOCAP_SEQUENTIAL]
+**
[SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
+**
[SQLITE_IOCAP_POWERSAFE_OVERWRITE]
+**
[SQLITE_IOCAP_IMMUTABLE]
+**
[SQLITE_IOCAP_BATCH_ATOMIC]
+**
+**
+** The SQLITE_IOCAP_ATOMIC property means that all writes of
+** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
+** mean that writes of blocks that are nnn bytes in size and
+** are aligned to an address which is an integer multiple of
+** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
+** that when data is appended to a file, the data is appended
+** first then the size of the file is extended, never the other
+** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
+** information is written to disk in the same order as calls
+** to xWrite().
+**
+** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
+** in the unread portions of the buffer with zeros. A VFS that
+** fails to zero-fill short reads might seem to work. However,
+** failure to zero-fill short reads will eventually lead to
+** database corruption.
+*/
+typedef struct sqlite3_io_methods sqlite3_io_methods;
+struct sqlite3_io_methods {
+ int iVersion;
+ int (*xClose)(sqlite3_file*);
+ int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
+ int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
+ int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
+ int (*xSync)(sqlite3_file*, int flags);
+ int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
+ int (*xLock)(sqlite3_file*, int);
+ int (*xUnlock)(sqlite3_file*, int);
+ int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
+ int (*xFileControl)(sqlite3_file*, int op, void *pArg);
+ int (*xSectorSize)(sqlite3_file*);
+ int (*xDeviceCharacteristics)(sqlite3_file*);
+ /* Methods above are valid for version 1 */
+ int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
+ int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
+ void (*xShmBarrier)(sqlite3_file*);
+ int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
+ /* Methods above are valid for version 2 */
+ int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
+ int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
+ /* Methods above are valid for version 3 */
+ /* Additional methods may be added in future releases */
+};
+
+/*
+** CAPI3REF: Standard File Control Opcodes
+** KEYWORDS: {file control opcodes} {file control opcode}
+**
+** These integer constants are opcodes for the xFileControl method
+** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
+** interface.
+**
+**
+**
[[SQLITE_FCNTL_LOCKSTATE]]
+** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
+** opcode causes the xFileControl method to write the current state of
+** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
+** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
+** into an integer that the pArg argument points to. This capability
+** is used during testing and is only available when the SQLITE_TEST
+** compile-time option is used.
+**
+**
[[SQLITE_FCNTL_SIZE_HINT]]
+** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
+** layer a hint of how large the database file will grow to be during the
+** current transaction. This hint is not guaranteed to be accurate but it
+** is often close. The underlying VFS might choose to preallocate database
+** file space based on this hint in order to help writes to the database
+** file run faster.
+**
+**
[[SQLITE_FCNTL_CHUNK_SIZE]]
+** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
+** extends and truncates the database file in chunks of a size specified
+** by the user. The fourth argument to [sqlite3_file_control()] should
+** point to an integer (type int) containing the new chunk-size to use
+** for the nominated database. Allocating database file space in large
+** chunks (say 1MB at a time), may reduce file-system fragmentation and
+** improve performance on some systems.
+**
+**
[[SQLITE_FCNTL_FILE_POINTER]]
+** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
+** to the [sqlite3_file] object associated with a particular database
+** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER].
+**
+**
[[SQLITE_FCNTL_JOURNAL_POINTER]]
+** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
+** to the [sqlite3_file] object associated with the journal file (either
+** the [rollback journal] or the [write-ahead log]) for a particular database
+** connection. See also [SQLITE_FCNTL_FILE_POINTER].
+**
+**
[[SQLITE_FCNTL_SYNC_OMITTED]]
+** No longer in use.
+**
+**
[[SQLITE_FCNTL_SYNC]]
+** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
+** sent to the VFS immediately before the xSync method is invoked on a
+** database file descriptor. Or, if the xSync method is not invoked
+** because the user has configured SQLite with
+** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
+** of the xSync method. In most cases, the pointer argument passed with
+** this file-control is NULL. However, if the database file is being synced
+** as part of a multi-database commit, the argument points to a nul-terminated
+** string containing the transactions master-journal file name. VFSes that
+** do not need this signal should silently ignore this opcode. Applications
+** should not call [sqlite3_file_control()] with this opcode as doing so may
+** disrupt the operation of the specialized VFSes that do require it.
+**
+**
[[SQLITE_FCNTL_COMMIT_PHASETWO]]
+** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
+** and sent to the VFS after a transaction has been committed immediately
+** but before the database is unlocked. VFSes that do not need this signal
+** should silently ignore this opcode. Applications should not call
+** [sqlite3_file_control()] with this opcode as doing so may disrupt the
+** operation of the specialized VFSes that do require it.
+**
+**
[[SQLITE_FCNTL_WIN32_AV_RETRY]]
+** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
+** retry counts and intervals for certain disk I/O operations for the
+** windows [VFS] in order to provide robustness in the presence of
+** anti-virus programs. By default, the windows VFS will retry file read,
+** file write, and file delete operations up to 10 times, with a delay
+** of 25 milliseconds before the first retry and with the delay increasing
+** by an additional 25 milliseconds with each subsequent retry. This
+** opcode allows these two values (10 retries and 25 milliseconds of delay)
+** to be adjusted. The values are changed for all database connections
+** within the same process. The argument is a pointer to an array of two
+** integers where the first integer is the new retry count and the second
+** integer is the delay. If either integer is negative, then the setting
+** is not changed but instead the prior value of that setting is written
+** into the array entry, allowing the current retry settings to be
+** interrogated. The zDbName parameter is ignored.
+**
+**
[[SQLITE_FCNTL_PERSIST_WAL]]
+** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
+** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
+** write ahead log ([WAL file]) and shared memory
+** files used for transaction control
+** are automatically deleted when the latest connection to the database
+** closes. Setting persistent WAL mode causes those files to persist after
+** close. Persisting the files is useful when other processes that do not
+** have write permission on the directory containing the database file want
+** to read the database file, as the WAL and shared memory files must exist
+** in order for the database to be readable. The fourth parameter to
+** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
+** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
+** WAL mode. If the integer is -1, then it is overwritten with the current
+** WAL persistence setting.
+**
+**
[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
+** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
+** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
+** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
+** xDeviceCharacteristics methods. The fourth parameter to
+** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
+** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
+** mode. If the integer is -1, then it is overwritten with the current
+** zero-damage mode setting.
+**
+**
[[SQLITE_FCNTL_OVERWRITE]]
+** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
+** a write transaction to indicate that, unless it is rolled back for some
+** reason, the entire database file will be overwritten by the current
+** transaction. This is used by VACUUM operations.
+**
+**
[[SQLITE_FCNTL_VFSNAME]]
+** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
+** all [VFSes] in the VFS stack. The names are of all VFS shims and the
+** final bottom-level VFS are written into memory obtained from
+** [sqlite3_malloc()] and the result is stored in the char* variable
+** that the fourth parameter of [sqlite3_file_control()] points to.
+** The caller is responsible for freeing the memory when done. As with
+** all file-control actions, there is no guarantee that this will actually
+** do anything. Callers should initialize the char* variable to a NULL
+** pointer in case this file-control is not implemented. This file-control
+** is intended for diagnostic use only.
+**
+**
[[SQLITE_FCNTL_VFS_POINTER]]
+** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
+** [VFSes] currently in use. ^(The argument X in
+** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
+** of type "[sqlite3_vfs] **". This opcodes will set *X
+** to a pointer to the top-level VFS.)^
+** ^When there are multiple VFS shims in the stack, this opcode finds the
+** upper-most shim only.
+**
+**
[[SQLITE_FCNTL_PRAGMA]]
+** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
+** file control is sent to the open [sqlite3_file] object corresponding
+** to the database file to which the pragma statement refers. ^The argument
+** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
+** pointers to strings (char**) in which the second element of the array
+** is the name of the pragma and the third element is the argument to the
+** pragma or NULL if the pragma has no argument. ^The handler for an
+** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
+** of the char** argument point to a string obtained from [sqlite3_mprintf()]
+** or the equivalent and that string will become the result of the pragma or
+** the error message if the pragma fails. ^If the
+** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
+** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
+** file control returns [SQLITE_OK], then the parser assumes that the
+** VFS has handled the PRAGMA itself and the parser generates a no-op
+** prepared statement if result string is NULL, or that returns a copy
+** of the result string if the string is non-NULL.
+** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
+** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
+** that the VFS encountered an error while handling the [PRAGMA] and the
+** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
+** file control occurs at the beginning of pragma statement analysis and so
+** it is able to override built-in [PRAGMA] statements.
+**
+**
[[SQLITE_FCNTL_BUSYHANDLER]]
+** ^The [SQLITE_FCNTL_BUSYHANDLER]
+** file-control may be invoked by SQLite on the database file handle
+** shortly after it is opened in order to provide a custom VFS with access
+** to the connections busy-handler callback. The argument is of type (void **)
+** - an array of two (void *) values. The first (void *) actually points
+** to a function of type (int (*)(void *)). In order to invoke the connections
+** busy-handler, this function should be invoked with the second (void *) in
+** the array as the only argument. If it returns non-zero, then the operation
+** should be retried. If it returns zero, the custom VFS should abandon the
+** current operation.
+**
+**
[[SQLITE_FCNTL_TEMPFILENAME]]
+** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
+** to have SQLite generate a
+** temporary filename using the same algorithm that is followed to generate
+** temporary filenames for TEMP tables and other internal uses. The
+** argument should be a char** which will be filled with the filename
+** written into memory obtained from [sqlite3_malloc()]. The caller should
+** invoke [sqlite3_free()] on the result to avoid a memory leak.
+**
+**
[[SQLITE_FCNTL_MMAP_SIZE]]
+** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
+** maximum number of bytes that will be used for memory-mapped I/O.
+** The argument is a pointer to a value of type sqlite3_int64 that
+** is an advisory maximum number of bytes in the file to memory map. The
+** pointer is overwritten with the old value. The limit is not changed if
+** the value originally pointed to is negative, and so the current limit
+** can be queried by passing in a pointer to a negative number. This
+** file-control is used internally to implement [PRAGMA mmap_size].
+**
+**
[[SQLITE_FCNTL_TRACE]]
+** The [SQLITE_FCNTL_TRACE] file control provides advisory information
+** to the VFS about what the higher layers of the SQLite stack are doing.
+** This file control is used by some VFS activity tracing [shims].
+** The argument is a zero-terminated string. Higher layers in the
+** SQLite stack may generate instances of this file control if
+** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
+**
+**
[[SQLITE_FCNTL_HAS_MOVED]]
+** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
+** pointer to an integer and it writes a boolean into that integer depending
+** on whether or not the file has been renamed, moved, or deleted since it
+** was first opened.
+**
+**
[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
+** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
+** underlying native file handle associated with a file handle. This file
+** control interprets its argument as a pointer to a native file handle and
+** writes the resulting value there.
+**
+**
[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
+** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This
+** opcode causes the xFileControl method to swap the file handle with the one
+** pointed to by the pArg argument. This capability is used during testing
+** and only needs to be supported when SQLITE_TEST is defined.
+**
+**
[[SQLITE_FCNTL_WAL_BLOCK]]
+** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
+** be advantageous to block on the next WAL lock if the lock is not immediately
+** available. The WAL subsystem issues this signal during rare
+** circumstances in order to fix a problem with priority inversion.
+** Applications should not use this file-control.
+**
+**
[[SQLITE_FCNTL_ZIPVFS]]
+** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
+** VFS should return SQLITE_NOTFOUND for this opcode.
+**
+**
[[SQLITE_FCNTL_RBU]]
+** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
+** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for
+** this opcode.
+**
+**
[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
+** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
+** the file descriptor is placed in "batch write mode", which
+** means all subsequent write operations will be deferred and done
+** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems
+** that do not support batch atomic writes will return SQLITE_NOTFOUND.
+** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
+** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
+** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
+** no VFS interface calls on the same [sqlite3_file] file descriptor
+** except for calls to the xWrite method and the xFileControl method
+** with [SQLITE_FCNTL_SIZE_HINT].
+**
+**
[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
+** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
+** operations since the previous successful call to
+** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
+** This file control returns [SQLITE_OK] if and only if the writes were
+** all performed successfully and have been committed to persistent storage.
+** ^Regardless of whether or not it is successful, this file control takes
+** the file descriptor out of batch write mode so that all subsequent
+** write operations are independent.
+** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
+** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
+**
+**
[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
+** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
+** operations since the previous successful call to
+** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
+** ^This file control takes the file descriptor out of batch write mode
+** so that all subsequent write operations are independent.
+** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
+** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
+**
+**
[[SQLITE_FCNTL_LOCK_TIMEOUT]]
+** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode causes attempts to obtain
+** a file lock using the xLock or xShmLock methods of the VFS to wait
+** for up to M milliseconds before failing, where M is the single
+** unsigned integer parameter.
+**
+**
[[SQLITE_FCNTL_DATA_VERSION]]
+** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
+** a database file. The argument is a pointer to a 32-bit unsigned integer.
+** The "data version" for the pager is written into the pointer. The
+** "data version" changes whenever any change occurs to the corresponding
+** database file, either through SQL statements on the same database
+** connection or through transactions committed by separate database
+** connections possibly in other processes. The [sqlite3_total_changes()]
+** interface can be used to find if any database on the connection has changed,
+** but that interface responds to changes on TEMP as well as MAIN and does
+** not provide a mechanism to detect changes to MAIN only. Also, the
+** [sqlite3_total_changes()] interface responds to internal changes only and
+** omits changes made by other database connections. The
+** [PRAGMA data_version] command provide a mechanism to detect changes to
+** a single attached database that occur due to other database connections,
+** but omits changes implemented by the database connection on which it is
+** called. This file control is the only mechanism to detect changes that
+** happen either internally or externally and that are associated with
+** a particular attached database.
+**
+*/
+#define SQLITE_FCNTL_LOCKSTATE 1
+#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2
+#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3
+#define SQLITE_FCNTL_LAST_ERRNO 4
+#define SQLITE_FCNTL_SIZE_HINT 5
+#define SQLITE_FCNTL_CHUNK_SIZE 6
+#define SQLITE_FCNTL_FILE_POINTER 7
+#define SQLITE_FCNTL_SYNC_OMITTED 8
+#define SQLITE_FCNTL_WIN32_AV_RETRY 9
+#define SQLITE_FCNTL_PERSIST_WAL 10
+#define SQLITE_FCNTL_OVERWRITE 11
+#define SQLITE_FCNTL_VFSNAME 12
+#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
+#define SQLITE_FCNTL_PRAGMA 14
+#define SQLITE_FCNTL_BUSYHANDLER 15
+#define SQLITE_FCNTL_TEMPFILENAME 16
+#define SQLITE_FCNTL_MMAP_SIZE 18
+#define SQLITE_FCNTL_TRACE 19
+#define SQLITE_FCNTL_HAS_MOVED 20
+#define SQLITE_FCNTL_SYNC 21
+#define SQLITE_FCNTL_COMMIT_PHASETWO 22
+#define SQLITE_FCNTL_WIN32_SET_HANDLE 23
+#define SQLITE_FCNTL_WAL_BLOCK 24
+#define SQLITE_FCNTL_ZIPVFS 25
+#define SQLITE_FCNTL_RBU 26
+#define SQLITE_FCNTL_VFS_POINTER 27
+#define SQLITE_FCNTL_JOURNAL_POINTER 28
+#define SQLITE_FCNTL_WIN32_GET_HANDLE 29
+#define SQLITE_FCNTL_PDB 30
+#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31
+#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32
+#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33
+#define SQLITE_FCNTL_LOCK_TIMEOUT 34
+#define SQLITE_FCNTL_DATA_VERSION 35
+
+/* deprecated names */
+#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE
+#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE
+#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO
+
+
+/*
+** CAPI3REF: Mutex Handle
+**
+** The mutex module within SQLite defines [sqlite3_mutex] to be an
+** abstract type for a mutex object. The SQLite core never looks
+** at the internal representation of an [sqlite3_mutex]. It only
+** deals with pointers to the [sqlite3_mutex] object.
+**
+** Mutexes are created using [sqlite3_mutex_alloc()].
+*/
+typedef struct sqlite3_mutex sqlite3_mutex;
+
+/*
+** CAPI3REF: Loadable Extension Thunk
+**
+** A pointer to the opaque sqlite3_api_routines structure is passed as
+** the third parameter to entry points of [loadable extensions]. This
+** structure must be typedefed in order to work around compiler warnings
+** on some platforms.
+*/
+typedef struct sqlite3_api_routines sqlite3_api_routines;
+
+/*
+** CAPI3REF: OS Interface Object
+**
+** An instance of the sqlite3_vfs object defines the interface between
+** the SQLite core and the underlying operating system. The "vfs"
+** in the name of the object stands for "virtual file system". See
+** the [VFS | VFS documentation] for further information.
+**
+** The VFS interface is sometimes extended by adding new methods onto
+** the end. Each time such an extension occurs, the iVersion field
+** is incremented. The iVersion value started out as 1 in
+** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
+** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
+** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields
+** may be appended to the sqlite3_vfs object and the iVersion value
+** may increase again in future versions of SQLite.
+** Note that the structure
+** of the sqlite3_vfs object changes in the transition from
+** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
+** and yet the iVersion field was not modified.
+**
+** The szOsFile field is the size of the subclassed [sqlite3_file]
+** structure used by this VFS. mxPathname is the maximum length of
+** a pathname in this VFS.
+**
+** Registered sqlite3_vfs objects are kept on a linked list formed by
+** the pNext pointer. The [sqlite3_vfs_register()]
+** and [sqlite3_vfs_unregister()] interfaces manage this list
+** in a thread-safe way. The [sqlite3_vfs_find()] interface
+** searches the list. Neither the application code nor the VFS
+** implementation should use the pNext pointer.
+**
+** The pNext field is the only field in the sqlite3_vfs
+** structure that SQLite will ever modify. SQLite will only access
+** or modify this field while holding a particular static mutex.
+** The application should never modify anything within the sqlite3_vfs
+** object once the object has been registered.
+**
+** The zName field holds the name of the VFS module. The name must
+** be unique across all VFS modules.
+**
+** [[sqlite3_vfs.xOpen]]
+** ^SQLite guarantees that the zFilename parameter to xOpen
+** is either a NULL pointer or string obtained
+** from xFullPathname() with an optional suffix added.
+** ^If a suffix is added to the zFilename parameter, it will
+** consist of a single "-" character followed by no more than
+** 11 alphanumeric and/or "-" characters.
+** ^SQLite further guarantees that
+** the string will be valid and unchanged until xClose() is
+** called. Because of the previous sentence,
+** the [sqlite3_file] can safely store a pointer to the
+** filename if it needs to remember the filename for some reason.
+** If the zFilename parameter to xOpen is a NULL pointer then xOpen
+** must invent its own temporary name for the file. ^Whenever the
+** xFilename parameter is NULL it will also be the case that the
+** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
+**
+** The flags argument to xOpen() includes all bits set in
+** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
+** or [sqlite3_open16()] is used, then flags includes at least
+** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
+** If xOpen() opens a file read-only then it sets *pOutFlags to
+** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
+**
+** ^(SQLite will also add one of the following flags to the xOpen()
+** call, depending on the object being opened:
+**
+**
+**
[SQLITE_OPEN_MAIN_DB]
+**
[SQLITE_OPEN_MAIN_JOURNAL]
+**
[SQLITE_OPEN_TEMP_DB]
+**
[SQLITE_OPEN_TEMP_JOURNAL]
+**
[SQLITE_OPEN_TRANSIENT_DB]
+**
[SQLITE_OPEN_SUBJOURNAL]
+**
[SQLITE_OPEN_MASTER_JOURNAL]
+**
[SQLITE_OPEN_WAL]
+**
)^
+**
+** The file I/O implementation can use the object type flags to
+** change the way it deals with files. For example, an application
+** that does not care about crash recovery or rollback might make
+** the open of a journal file a no-op. Writes to this journal would
+** also be no-ops, and any attempt to read the journal would return
+** SQLITE_IOERR. Or the implementation might recognize that a database
+** file will be doing page-aligned sector reads and writes in a random
+** order and set up its I/O subsystem accordingly.
+**
+** SQLite might also add one of the following flags to the xOpen method:
+**
+**
+**
[SQLITE_OPEN_DELETEONCLOSE]
+**
[SQLITE_OPEN_EXCLUSIVE]
+**
+**
+** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
+** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
+** will be set for TEMP databases and their journals, transient
+** databases, and subjournals.
+**
+** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
+** with the [SQLITE_OPEN_CREATE] flag, which are both directly
+** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
+** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
+** SQLITE_OPEN_CREATE, is used to indicate that file should always
+** be created, and that it is an error if it already exists.
+** It is not used to indicate the file should be opened
+** for exclusive access.
+**
+** ^At least szOsFile bytes of memory are allocated by SQLite
+** to hold the [sqlite3_file] structure passed as the third
+** argument to xOpen. The xOpen method does not have to
+** allocate the structure; it should just fill it in. Note that
+** the xOpen method must set the sqlite3_file.pMethods to either
+** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
+** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
+** element will be valid after xOpen returns regardless of the success
+** or failure of the xOpen call.
+**
+** [[sqlite3_vfs.xAccess]]
+** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
+** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
+** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
+** to test whether a file is at least readable. The file can be a
+** directory.
+**
+** ^SQLite will always allocate at least mxPathname+1 bytes for the
+** output buffer xFullPathname. The exact size of the output buffer
+** is also passed as a parameter to both methods. If the output buffer
+** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
+** handled as a fatal error by SQLite, vfs implementations should endeavor
+** to prevent this by setting mxPathname to a sufficiently large value.
+**
+** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
+** interfaces are not strictly a part of the filesystem, but they are
+** included in the VFS structure for completeness.
+** The xRandomness() function attempts to return nBytes bytes
+** of good-quality randomness into zOut. The return value is
+** the actual number of bytes of randomness obtained.
+** The xSleep() method causes the calling thread to sleep for at
+** least the number of microseconds given. ^The xCurrentTime()
+** method returns a Julian Day Number for the current date and time as
+** a floating point value.
+** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
+** Day Number multiplied by 86400000 (the number of milliseconds in
+** a 24-hour day).
+** ^SQLite will use the xCurrentTimeInt64() method to get the current
+** date and time if that method is available (if iVersion is 2 or
+** greater and the function pointer is not NULL) and will fall back
+** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
+**
+** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
+** are not used by the SQLite core. These optional interfaces are provided
+** by some VFSes to facilitate testing of the VFS code. By overriding
+** system calls with functions under its control, a test program can
+** simulate faults and error conditions that would otherwise be difficult
+** or impossible to induce. The set of system calls that can be overridden
+** varies from one VFS to another, and from one version of the same VFS to the
+** next. Applications that use these interfaces must be prepared for any
+** or all of these interfaces to be NULL or for their behavior to change
+** from one release to the next. Applications must not attempt to access
+** any of these methods if the iVersion of the VFS is less than 3.
+*/
+typedef struct sqlite3_vfs sqlite3_vfs;
+typedef void (*sqlite3_syscall_ptr)(void);
+struct sqlite3_vfs {
+ int iVersion; /* Structure version number (currently 3) */
+ int szOsFile; /* Size of subclassed sqlite3_file */
+ int mxPathname; /* Maximum file pathname length */
+ sqlite3_vfs *pNext; /* Next registered VFS */
+ const char *zName; /* Name of this virtual file system */
+ void *pAppData; /* Pointer to application-specific data */
+ int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
+ int flags, int *pOutFlags);
+ int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
+ int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
+ int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
+ void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
+ void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
+ void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
+ void (*xDlClose)(sqlite3_vfs*, void*);
+ int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
+ int (*xSleep)(sqlite3_vfs*, int microseconds);
+ int (*xCurrentTime)(sqlite3_vfs*, double*);
+ int (*xGetLastError)(sqlite3_vfs*, int, char *);
+ /*
+ ** The methods above are in version 1 of the sqlite_vfs object
+ ** definition. Those that follow are added in version 2 or later
+ */
+ int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
+ /*
+ ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
+ ** Those below are for version 3 and greater.
+ */
+ int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
+ sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
+ const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
+ /*
+ ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
+ ** New fields may be appended in future versions. The iVersion
+ ** value will increment whenever this happens.
+ */
+};
+
+/*
+** CAPI3REF: Flags for the xAccess VFS method
+**
+** These integer constants can be used as the third parameter to
+** the xAccess method of an [sqlite3_vfs] object. They determine
+** what kind of permissions the xAccess method is looking for.
+** With SQLITE_ACCESS_EXISTS, the xAccess method
+** simply checks whether the file exists.
+** With SQLITE_ACCESS_READWRITE, the xAccess method
+** checks whether the named directory is both readable and writable
+** (in other words, if files can be added, removed, and renamed within
+** the directory).
+** The SQLITE_ACCESS_READWRITE constant is currently used only by the
+** [temp_store_directory pragma], though this could change in a future
+** release of SQLite.
+** With SQLITE_ACCESS_READ, the xAccess method
+** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
+** currently unused, though it might be used in a future release of
+** SQLite.
+*/
+#define SQLITE_ACCESS_EXISTS 0
+#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
+#define SQLITE_ACCESS_READ 2 /* Unused */
+
+/*
+** CAPI3REF: Flags for the xShmLock VFS method
+**
+** These integer constants define the various locking operations
+** allowed by the xShmLock method of [sqlite3_io_methods]. The
+** following are the only legal combinations of flags to the
+** xShmLock method:
+**
+**
+**
SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
+**
SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
+**
SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
+**
SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
+**
+**
+** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
+** was given on the corresponding lock.
+**
+** The xShmLock method can transition between unlocked and SHARED or
+** between unlocked and EXCLUSIVE. It cannot transition between SHARED
+** and EXCLUSIVE.
+*/
+#define SQLITE_SHM_UNLOCK 1
+#define SQLITE_SHM_LOCK 2
+#define SQLITE_SHM_SHARED 4
+#define SQLITE_SHM_EXCLUSIVE 8
+
+/*
+** CAPI3REF: Maximum xShmLock index
+**
+** The xShmLock method on [sqlite3_io_methods] may use values
+** between 0 and this upper bound as its "offset" argument.
+** The SQLite core will never attempt to acquire or release a
+** lock outside of this range
+*/
+#define SQLITE_SHM_NLOCK 8
+
+
+/*
+** CAPI3REF: Initialize The SQLite Library
+**
+** ^The sqlite3_initialize() routine initializes the
+** SQLite library. ^The sqlite3_shutdown() routine
+** deallocates any resources that were allocated by sqlite3_initialize().
+** These routines are designed to aid in process initialization and
+** shutdown on embedded systems. Workstation applications using
+** SQLite normally do not need to invoke either of these routines.
+**
+** A call to sqlite3_initialize() is an "effective" call if it is
+** the first time sqlite3_initialize() is invoked during the lifetime of
+** the process, or if it is the first time sqlite3_initialize() is invoked
+** following a call to sqlite3_shutdown(). ^(Only an effective call
+** of sqlite3_initialize() does any initialization. All other calls
+** are harmless no-ops.)^
+**
+** A call to sqlite3_shutdown() is an "effective" call if it is the first
+** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
+** an effective call to sqlite3_shutdown() does any deinitialization.
+** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
+**
+** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
+** is not. The sqlite3_shutdown() interface must only be called from a
+** single thread. All open [database connections] must be closed and all
+** other SQLite resources must be deallocated prior to invoking
+** sqlite3_shutdown().
+**
+** Among other things, ^sqlite3_initialize() will invoke
+** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
+** will invoke sqlite3_os_end().
+**
+** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
+** ^If for some reason, sqlite3_initialize() is unable to initialize
+** the library (perhaps it is unable to allocate a needed resource such
+** as a mutex) it returns an [error code] other than [SQLITE_OK].
+**
+** ^The sqlite3_initialize() routine is called internally by many other
+** SQLite interfaces so that an application usually does not need to
+** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
+** calls sqlite3_initialize() so the SQLite library will be automatically
+** initialized when [sqlite3_open()] is called if it has not be initialized
+** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
+** compile-time option, then the automatic calls to sqlite3_initialize()
+** are omitted and the application must call sqlite3_initialize() directly
+** prior to using any other SQLite interface. For maximum portability,
+** it is recommended that applications always invoke sqlite3_initialize()
+** directly prior to using any other SQLite interface. Future releases
+** of SQLite may require this. In other words, the behavior exhibited
+** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
+** default behavior in some future release of SQLite.
+**
+** The sqlite3_os_init() routine does operating-system specific
+** initialization of the SQLite library. The sqlite3_os_end()
+** routine undoes the effect of sqlite3_os_init(). Typical tasks
+** performed by these routines include allocation or deallocation
+** of static resources, initialization of global variables,
+** setting up a default [sqlite3_vfs] module, or setting up
+** a default configuration using [sqlite3_config()].
+**
+** The application should never invoke either sqlite3_os_init()
+** or sqlite3_os_end() directly. The application should only invoke
+** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
+** interface is called automatically by sqlite3_initialize() and
+** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
+** implementations for sqlite3_os_init() and sqlite3_os_end()
+** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
+** When [custom builds | built for other platforms]
+** (using the [SQLITE_OS_OTHER=1] compile-time
+** option) the application must supply a suitable implementation for
+** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
+** implementation of sqlite3_os_init() or sqlite3_os_end()
+** must return [SQLITE_OK] on success and some other [error code] upon
+** failure.
+*/
+SQLITE_API int sqlite3_initialize(void);
+SQLITE_API int sqlite3_shutdown(void);
+SQLITE_API int sqlite3_os_init(void);
+SQLITE_API int sqlite3_os_end(void);
+
+/*
+** CAPI3REF: Configuring The SQLite Library
+**
+** The sqlite3_config() interface is used to make global configuration
+** changes to SQLite in order to tune SQLite to the specific needs of
+** the application. The default configuration is recommended for most
+** applications and so this routine is usually not necessary. It is
+** provided to support rare applications with unusual needs.
+**
+** The sqlite3_config() interface is not threadsafe. The application
+** must ensure that no other SQLite interfaces are invoked by other
+** threads while sqlite3_config() is running.
+**
+** The sqlite3_config() interface
+** may only be invoked prior to library initialization using
+** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
+** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
+** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
+** Note, however, that ^sqlite3_config() can be called as part of the
+** implementation of an application-defined [sqlite3_os_init()].
+**
+** The first argument to sqlite3_config() is an integer
+** [configuration option] that determines
+** what property of SQLite is to be configured. Subsequent arguments
+** vary depending on the [configuration option]
+** in the first argument.
+**
+** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
+** ^If the option is unknown or SQLite is unable to set the option
+** then this routine returns a non-zero [error code].
+*/
+SQLITE_API int sqlite3_config(int, ...);
+
+/*
+** CAPI3REF: Configure database connections
+** METHOD: sqlite3
+**
+** The sqlite3_db_config() interface is used to make configuration
+** changes to a [database connection]. The interface is similar to
+** [sqlite3_config()] except that the changes apply to a single
+** [database connection] (specified in the first argument).
+**
+** The second argument to sqlite3_db_config(D,V,...) is the
+** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
+** that indicates what aspect of the [database connection] is being configured.
+** Subsequent arguments vary depending on the configuration verb.
+**
+** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
+** the call is considered successful.
+*/
+SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
+
+/*
+** CAPI3REF: Memory Allocation Routines
+**
+** An instance of this object defines the interface between SQLite
+** and low-level memory allocation routines.
+**
+** This object is used in only one place in the SQLite interface.
+** A pointer to an instance of this object is the argument to
+** [sqlite3_config()] when the configuration option is
+** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
+** By creating an instance of this object
+** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
+** during configuration, an application can specify an alternative
+** memory allocation subsystem for SQLite to use for all of its
+** dynamic memory needs.
+**
+** Note that SQLite comes with several [built-in memory allocators]
+** that are perfectly adequate for the overwhelming majority of applications
+** and that this object is only useful to a tiny minority of applications
+** with specialized memory allocation requirements. This object is
+** also used during testing of SQLite in order to specify an alternative
+** memory allocator that simulates memory out-of-memory conditions in
+** order to verify that SQLite recovers gracefully from such
+** conditions.
+**
+** The xMalloc, xRealloc, and xFree methods must work like the
+** malloc(), realloc() and free() functions from the standard C library.
+** ^SQLite guarantees that the second argument to
+** xRealloc is always a value returned by a prior call to xRoundup.
+**
+** xSize should return the allocated size of a memory allocation
+** previously obtained from xMalloc or xRealloc. The allocated size
+** is always at least as big as the requested size but may be larger.
+**
+** The xRoundup method returns what would be the allocated size of
+** a memory allocation given a particular requested size. Most memory
+** allocators round up memory allocations at least to the next multiple
+** of 8. Some allocators round up to a larger multiple or to a power of 2.
+** Every memory allocation request coming in through [sqlite3_malloc()]
+** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
+** that causes the corresponding memory allocation to fail.
+**
+** The xInit method initializes the memory allocator. For example,
+** it might allocate any require mutexes or initialize internal data
+** structures. The xShutdown method is invoked (indirectly) by
+** [sqlite3_shutdown()] and should deallocate any resources acquired
+** by xInit. The pAppData pointer is used as the only parameter to
+** xInit and xShutdown.
+**
+** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
+** the xInit method, so the xInit method need not be threadsafe. The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either. For all other methods, SQLite
+** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
+** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
+** it is by default) and so the methods are automatically serialized.
+** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
+** methods must be threadsafe or else make their own arrangements for
+** serialization.
+**
+** SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+*/
+typedef struct sqlite3_mem_methods sqlite3_mem_methods;
+struct sqlite3_mem_methods {
+ void *(*xMalloc)(int); /* Memory allocation function */
+ void (*xFree)(void*); /* Free a prior allocation */
+ void *(*xRealloc)(void*,int); /* Resize an allocation */
+ int (*xSize)(void*); /* Return the size of an allocation */
+ int (*xRoundup)(int); /* Round up request size to allocation size */
+ int (*xInit)(void*); /* Initialize the memory allocator */
+ void (*xShutdown)(void*); /* Deinitialize the memory allocator */
+ void *pAppData; /* Argument to xInit() and xShutdown() */
+};
+
+/*
+** CAPI3REF: Configuration Options
+** KEYWORDS: {configuration option}
+**
+** These constants are the available integer configuration options that
+** can be passed as the first argument to the [sqlite3_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued. Applications
+** should check the return code from [sqlite3_config()] to make sure that
+** the call worked. The [sqlite3_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+**
+** [[SQLITE_CONFIG_SINGLETHREAD]]
SQLITE_CONFIG_SINGLETHREAD
+**
There are no arguments to this option. ^This option sets the
+** [threading mode] to Single-thread. In other words, it disables
+** all mutexing and puts SQLite into a mode where it can only be used
+** by a single thread. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to change the [threading mode] from its default
+** value of Single-thread and so [sqlite3_config()] will return
+** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
+** configuration option.
+**
+** [[SQLITE_CONFIG_MULTITHREAD]]
SQLITE_CONFIG_MULTITHREAD
+**
There are no arguments to this option. ^This option sets the
+** [threading mode] to Multi-thread. In other words, it disables
+** mutexing on [database connection] and [prepared statement] objects.
+** The application is responsible for serializing access to
+** [database connections] and [prepared statements]. But other mutexes
+** are enabled so that SQLite will be safe to use in a multi-threaded
+** environment as long as no two threads attempt to use the same
+** [database connection] at the same time. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to set the Multi-thread [threading mode] and
+** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
+** SQLITE_CONFIG_MULTITHREAD configuration option.
+**
+** [[SQLITE_CONFIG_SERIALIZED]]
SQLITE_CONFIG_SERIALIZED
+**
There are no arguments to this option. ^This option sets the
+** [threading mode] to Serialized. In other words, this option enables
+** all mutexes including the recursive
+** mutexes on [database connection] and [prepared statement] objects.
+** In this mode (which is the default when SQLite is compiled with
+** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
+** to [database connections] and [prepared statements] so that the
+** application is free to use the same [database connection] or the
+** same [prepared statement] in different threads at the same time.
+** ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to set the Serialized [threading mode] and
+** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
+** SQLITE_CONFIG_SERIALIZED configuration option.
+**
+** [[SQLITE_CONFIG_MALLOC]]
SQLITE_CONFIG_MALLOC
+**
^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
+** a pointer to an instance of the [sqlite3_mem_methods] structure.
+** The argument specifies
+** alternative low-level memory allocation routines to be used in place of
+** the memory allocation routines built into SQLite.)^ ^SQLite makes
+** its own private copy of the content of the [sqlite3_mem_methods] structure
+** before the [sqlite3_config()] call returns.
+**
+** [[SQLITE_CONFIG_GETMALLOC]]
SQLITE_CONFIG_GETMALLOC
+**
^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
+** is a pointer to an instance of the [sqlite3_mem_methods] structure.
+** The [sqlite3_mem_methods]
+** structure is filled with the currently defined memory allocation routines.)^
+** This option can be used to overload the default memory allocation
+** routines with a wrapper that simulations memory allocation failure or
+** tracks memory usage, for example.
+**
+** [[SQLITE_CONFIG_SMALL_MALLOC]]
SQLITE_CONFIG_SMALL_MALLOC
+**
^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
+** type int, interpreted as a boolean, which if true provides a hint to
+** SQLite that it should avoid large memory allocations if possible.
+** SQLite will run faster if it is free to make large memory allocations,
+** but some application might prefer to run slower in exchange for
+** guarantees about memory fragmentation that are possible if large
+** allocations are avoided. This hint is normally off.
+**
+**
+** [[SQLITE_CONFIG_MEMSTATUS]]
SQLITE_CONFIG_MEMSTATUS
+**
^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
+** interpreted as a boolean, which enables or disables the collection of
+** memory allocation statistics. ^(When memory allocation statistics are
+** disabled, the following SQLite interfaces become non-operational:
+**
+**
[sqlite3_memory_used()]
+**
[sqlite3_memory_highwater()]
+**
[sqlite3_soft_heap_limit64()]
+**
[sqlite3_status64()]
+**
)^
+** ^Memory allocation statistics are enabled by default unless SQLite is
+** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
+** allocation statistics are disabled by default.
+**
+**
+** [[SQLITE_CONFIG_SCRATCH]]
SQLITE_CONFIG_SCRATCH
+**
The SQLITE_CONFIG_SCRATCH option is no longer used.
+**
+**
+** [[SQLITE_CONFIG_PAGECACHE]]
SQLITE_CONFIG_PAGECACHE
+**
^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
+** that SQLite can use for the database page cache with the default page
+** cache implementation.
+** This configuration option is a no-op if an application-define page
+** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
+** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
+** 8-byte aligned memory (pMem), the size of each page cache line (sz),
+** and the number of cache lines (N).
+** The sz argument should be the size of the largest database page
+** (a power of two between 512 and 65536) plus some extra bytes for each
+** page header. ^The number of extra bytes needed by the page header
+** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
+** ^It is harmless, apart from the wasted memory,
+** for the sz parameter to be larger than necessary. The pMem
+** argument must be either a NULL pointer or a pointer to an 8-byte
+** aligned block of memory of at least sz*N bytes, otherwise
+** subsequent behavior is undefined.
+** ^When pMem is not NULL, SQLite will strive to use the memory provided
+** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
+** a page cache line is larger than sz bytes or if all of the pMem buffer
+** is exhausted.
+** ^If pMem is NULL and N is non-zero, then each database connection
+** does an initial bulk allocation for page cache memory
+** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
+** of -1024*N bytes if N is negative, . ^If additional
+** page cache memory is needed beyond what is provided by the initial
+** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
+** additional cache line.
+**
+** [[SQLITE_CONFIG_HEAP]]
SQLITE_CONFIG_HEAP
+**
^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
+** that SQLite will use for all of its dynamic memory allocation needs
+** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
+** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
+** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
+** [SQLITE_ERROR] if invoked otherwise.
+** ^There are three arguments to SQLITE_CONFIG_HEAP:
+** An 8-byte aligned pointer to the memory,
+** the number of bytes in the memory buffer, and the minimum allocation size.
+** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
+** to using its default memory allocator (the system malloc() implementation),
+** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
+** memory pointer is not NULL then the alternative memory
+** allocator is engaged to handle all of SQLites memory allocation needs.
+** The first pointer (the memory pointer) must be aligned to an 8-byte
+** boundary or subsequent behavior of SQLite will be undefined.
+** The minimum allocation size is capped at 2**12. Reasonable values
+** for the minimum allocation size are 2**5 through 2**8.
+**
+** [[SQLITE_CONFIG_MUTEX]]
SQLITE_CONFIG_MUTEX
+**
^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
+** pointer to an instance of the [sqlite3_mutex_methods] structure.
+** The argument specifies alternative low-level mutex routines to be used
+** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of
+** the content of the [sqlite3_mutex_methods] structure before the call to
+** [sqlite3_config()] returns. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** the entire mutexing subsystem is omitted from the build and hence calls to
+** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
+** return [SQLITE_ERROR].
+**
+** [[SQLITE_CONFIG_GETMUTEX]]
SQLITE_CONFIG_GETMUTEX
+**
^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
+** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The
+** [sqlite3_mutex_methods]
+** structure is filled with the currently defined mutex routines.)^
+** This option can be used to overload the default mutex allocation
+** routines with a wrapper used to track mutex usage for performance
+** profiling or testing, for example. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** the entire mutexing subsystem is omitted from the build and hence calls to
+** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
+** return [SQLITE_ERROR].
+**
+** [[SQLITE_CONFIG_LOOKASIDE]]
SQLITE_CONFIG_LOOKASIDE
+**
^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
+** the default size of lookaside memory on each [database connection].
+** The first argument is the
+** size of each lookaside buffer slot and the second is the number of
+** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE
+** sets the default lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
+** option to [sqlite3_db_config()] can be used to change the lookaside
+** configuration on individual connections.)^
+**
+** [[SQLITE_CONFIG_PCACHE2]]
SQLITE_CONFIG_PCACHE2
+**
^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
+** a pointer to an [sqlite3_pcache_methods2] object. This object specifies
+** the interface to a custom page cache implementation.)^
+** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.
+**
+** [[SQLITE_CONFIG_GETPCACHE2]]
SQLITE_CONFIG_GETPCACHE2
+**
^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
+** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of
+** the current page cache implementation into that object.)^
+**
+** [[SQLITE_CONFIG_LOG]]
SQLITE_CONFIG_LOG
+**
The SQLITE_CONFIG_LOG option is used to configure the SQLite
+** global [error log].
+** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
+** function with a call signature of void(*)(void*,int,const char*),
+** and a pointer to void. ^If the function pointer is not NULL, it is
+** invoked by [sqlite3_log()] to process each logging event. ^If the
+** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
+** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
+** passed through as the first parameter to the application-defined logger
+** function whenever that function is invoked. ^The second parameter to
+** the logger function is a copy of the first parameter to the corresponding
+** [sqlite3_log()] call and is intended to be a [result code] or an
+** [extended result code]. ^The third parameter passed to the logger is
+** log message after formatting via [sqlite3_snprintf()].
+** The SQLite logging interface is not reentrant; the logger function
+** supplied by the application must not invoke any SQLite interface.
+** In a multi-threaded application, the application-defined logger
+** function must be threadsafe.
+**
+** [[SQLITE_CONFIG_URI]]
SQLITE_CONFIG_URI
+**
^(The SQLITE_CONFIG_URI option takes a single argument of type int.
+** If non-zero, then URI handling is globally enabled. If the parameter is zero,
+** then URI handling is globally disabled.)^ ^If URI handling is globally
+** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
+** [sqlite3_open16()] or
+** specified as part of [ATTACH] commands are interpreted as URIs, regardless
+** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
+** connection is opened. ^If it is globally disabled, filenames are
+** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
+** database connection is opened. ^(By default, URI handling is globally
+** disabled. The default value may be changed by compiling with the
+** [SQLITE_USE_URI] symbol defined.)^
+**
+** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]]
SQLITE_CONFIG_COVERING_INDEX_SCAN
+**
^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
+** argument which is interpreted as a boolean in order to enable or disable
+** the use of covering indices for full table scans in the query optimizer.
+** ^The default setting is determined
+** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
+** if that compile-time option is omitted.
+** The ability to disable the use of covering indices for full table scans
+** is because some incorrectly coded legacy applications might malfunction
+** when the optimization is enabled. Providing the ability to
+** disable the optimization allows the older, buggy application code to work
+** without change even with newer versions of SQLite.
+**
+** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
+**
SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
+**
These options are obsolete and should not be used by new code.
+** They are retained for backwards compatibility but are now no-ops.
+**
+**
+** [[SQLITE_CONFIG_SQLLOG]]
+**
SQLITE_CONFIG_SQLLOG
+**
This option is only available if sqlite is compiled with the
+** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
+** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
+** The second should be of type (void*). The callback is invoked by the library
+** in three separate circumstances, identified by the value passed as the
+** fourth parameter. If the fourth parameter is 0, then the database connection
+** passed as the second argument has just been opened. The third argument
+** points to a buffer containing the name of the main database file. If the
+** fourth parameter is 1, then the SQL statement that the third parameter
+** points to has just been executed. Or, if the fourth parameter is 2, then
+** the connection being passed as the second parameter is being closed. The
+** third parameter is passed NULL In this case. An example of using this
+** configuration option can be seen in the "test_sqllog.c" source file in
+** the canonical SQLite source tree.
+**
+** [[SQLITE_CONFIG_MMAP_SIZE]]
+**
SQLITE_CONFIG_MMAP_SIZE
+**
^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
+** that are the default mmap size limit (the default setting for
+** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
+** ^The default setting can be overridden by each database connection using
+** either the [PRAGMA mmap_size] command, or by using the
+** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
+** will be silently truncated if necessary so that it does not exceed the
+** compile-time maximum mmap size set by the
+** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
+** ^If either argument to this option is negative, then that argument is
+** changed to its compile-time default.
+**
+** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
+**
SQLITE_CONFIG_WIN32_HEAPSIZE
+**
^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
+** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
+** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
+** that specifies the maximum size of the created heap.
+**
+** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
+**
SQLITE_CONFIG_PCACHE_HDRSZ
+**
^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
+** is a pointer to an integer and writes into that integer the number of extra
+** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
+** The amount of extra space required can change depending on the compiler,
+** target platform, and SQLite version.
+**
+** [[SQLITE_CONFIG_PMASZ]]
+**
SQLITE_CONFIG_PMASZ
+**
^The SQLITE_CONFIG_PMASZ option takes a single parameter which
+** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
+** sorter to that integer. The default minimum PMA Size is set by the
+** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched
+** to help with sort operations when multithreaded sorting
+** is enabled (using the [PRAGMA threads] command) and the amount of content
+** to be sorted exceeds the page size times the minimum of the
+** [PRAGMA cache_size] setting and this value.
+**
+** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
+**
SQLITE_CONFIG_STMTJRNL_SPILL
+**
^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
+** becomes the [statement journal] spill-to-disk threshold.
+** [Statement journals] are held in memory until their size (in bytes)
+** exceeds this threshold, at which point they are written to disk.
+** Or if the threshold is -1, statement journals are always held
+** exclusively in memory.
+** Since many statement journals never become large, setting the spill
+** threshold to a value such as 64KiB can greatly reduce the amount of
+** I/O required to support statement rollback.
+** The default value for this setting is controlled by the
+** [SQLITE_STMTJRNL_SPILL] compile-time option.
+**
+** [[SQLITE_CONFIG_SORTERREF_SIZE]]
+**
SQLITE_CONFIG_SORTERREF_SIZE
+**
The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
+** of type (int) - the new value of the sorter-reference size threshold.
+** Usually, when SQLite uses an external sort to order records according
+** to an ORDER BY clause, all fields required by the caller are present in the
+** sorted records. However, if SQLite determines based on the declared type
+** of a table column that its values are likely to be very large - larger
+** than the configured sorter-reference size threshold - then a reference
+** is stored in each sorted record and the required column values loaded
+** from the database as records are returned in sorted order. The default
+** value for this option is to never use this optimization. Specifying a
+** negative value for this option restores the default behaviour.
+** This option is only available if SQLite is compiled with the
+** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
+**
+*/
+#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
+#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
+#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
+#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */
+#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
+#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
+#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
+#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
+#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
+/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
+#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
+#define SQLITE_CONFIG_PCACHE 14 /* no-op */
+#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
+#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
+#define SQLITE_CONFIG_URI 17 /* int */
+#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
+#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
+#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
+#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
+#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
+#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
+#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */
+#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */
+#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */
+#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */
+#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */
+
+/*
+** CAPI3REF: Database Connection Configuration Options
+**
+** These constants are the available integer configuration options that
+** can be passed as the second argument to the [sqlite3_db_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued. Applications
+** should check the return code from [sqlite3_db_config()] to make sure that
+** the call worked. ^The [sqlite3_db_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+**
+**
SQLITE_DBCONFIG_LOOKASIDE
+**
^This option takes three additional arguments that determine the
+** [lookaside memory allocator] configuration for the [database connection].
+** ^The first argument (the third parameter to [sqlite3_db_config()] is a
+** pointer to a memory buffer to use for lookaside memory.
+** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
+** may be NULL in which case SQLite will allocate the
+** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
+** size of each lookaside buffer slot. ^The third argument is the number of
+** slots. The size of the buffer in the first argument must be greater than
+** or equal to the product of the second and third arguments. The buffer
+** must be aligned to an 8-byte boundary. ^If the second argument to
+** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
+** rounded down to the next smaller multiple of 8. ^(The lookaside memory
+** configuration for a database connection can only be changed when that
+** connection is not currently using lookaside memory, or in other words
+** when the "current value" returned by
+** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
+** Any attempt to change the lookaside memory configuration when lookaside
+** memory is in use leaves the configuration unchanged and returns
+** [SQLITE_BUSY].)^
+**
+**
SQLITE_DBCONFIG_ENABLE_FKEY
+**
^This option is used to enable or disable the enforcement of
+** [foreign key constraints]. There should be two additional arguments.
+** The first argument is an integer which is 0 to disable FK enforcement,
+** positive to enable FK enforcement or negative to leave FK enforcement
+** unchanged. The second parameter is a pointer to an integer into which
+** is written 0 or 1 to indicate whether FK enforcement is off or on
+** following this call. The second parameter may be a NULL pointer, in
+** which case the FK enforcement setting is not reported back.
+**
+**
SQLITE_DBCONFIG_ENABLE_TRIGGER
+**
^This option is used to enable or disable [CREATE TRIGGER | triggers].
+** There should be two additional arguments.
+** The first argument is an integer which is 0 to disable triggers,
+** positive to enable triggers or negative to leave the setting unchanged.
+** The second parameter is a pointer to an integer into which
+** is written 0 or 1 to indicate whether triggers are disabled or enabled
+** following this call. The second parameter may be a NULL pointer, in
+** which case the trigger setting is not reported back.
+**
+**
SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER
+**
^This option is used to enable or disable the two-argument
+** version of the [fts3_tokenizer()] function which is part of the
+** [FTS3] full-text search engine extension.
+** There should be two additional arguments.
+** The first argument is an integer which is 0 to disable fts3_tokenizer() or
+** positive to enable fts3_tokenizer() or negative to leave the setting
+** unchanged.
+** The second parameter is a pointer to an integer into which
+** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
+** following this call. The second parameter may be a NULL pointer, in
+** which case the new setting is not reported back.
+**
+**
SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION
+**
^This option is used to enable or disable the [sqlite3_load_extension()]
+** interface independently of the [load_extension()] SQL function.
+** The [sqlite3_enable_load_extension()] API enables or disables both the
+** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
+** There should be two additional arguments.
+** When the first argument to this interface is 1, then only the C-API is
+** enabled and the SQL function remains disabled. If the first argument to
+** this interface is 0, then both the C-API and the SQL function are disabled.
+** If the first argument is -1, then no changes are made to state of either the
+** C-API or the SQL function.
+** The second parameter is a pointer to an integer into which
+** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
+** is disabled or enabled following this call. The second parameter may
+** be a NULL pointer, in which case the new setting is not reported back.
+**
+**
+**
SQLITE_DBCONFIG_MAINDBNAME
+**
^This option is used to change the name of the "main" database
+** schema. ^The sole argument is a pointer to a constant UTF8 string
+** which will become the new schema name in place of "main". ^SQLite
+** does not make a copy of the new main schema name string, so the application
+** must ensure that the argument passed into this DBCONFIG option is unchanged
+** until after the database connection closes.
+**
+**
+**
SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE
+**
Usually, when a database in wal mode is closed or detached from a
+** database handle, SQLite checks if this will mean that there are now no
+** connections at all to the database. If so, it performs a checkpoint
+** operation before closing the connection. This option may be used to
+** override this behaviour. The first parameter passed to this operation
+** is an integer - positive to disable checkpoints-on-close, or zero (the
+** default) to enable them, and negative to leave the setting unchanged.
+** The second parameter is a pointer to an integer
+** into which is written 0 or 1 to indicate whether checkpoints-on-close
+** have been disabled - 0 if they are not disabled, 1 if they are.
+**
+**
+**
SQLITE_DBCONFIG_ENABLE_QPSG
+**
^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
+** the [query planner stability guarantee] (QPSG). When the QPSG is active,
+** a single SQL query statement will always use the same algorithm regardless
+** of values of [bound parameters].)^ The QPSG disables some query optimizations
+** that look at the values of bound parameters, which can make some queries
+** slower. But the QPSG has the advantage of more predictable behavior. With
+** the QPSG active, SQLite will always use the same query plan in the field as
+** was used during testing in the lab.
+** The first argument to this setting is an integer which is 0 to disable
+** the QPSG, positive to enable QPSG, or negative to leave the setting
+** unchanged. The second parameter is a pointer to an integer into which
+** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
+** following this call.
+**
+**
+**
SQLITE_DBCONFIG_TRIGGER_EQP
+**
By default, the output of EXPLAIN QUERY PLAN commands does not
+** include output for any operations performed by trigger programs. This
+** option is used to set or clear (the default) a flag that governs this
+** behavior. The first parameter passed to this operation is an integer -
+** positive to enable output for trigger programs, or zero to disable it,
+** or negative to leave the setting unchanged.
+** The second parameter is a pointer to an integer into which is written
+** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
+** it is not disabled, 1 if it is.
+**
+**
+**
SQLITE_DBCONFIG_RESET_DATABASE
+**
Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
+** [VACUUM] in order to reset a database back to an empty database
+** with no schema and no content. The following process works even for
+** a badly corrupted database file:
+**
+**
If the database connection is newly opened, make sure it has read the
+** database schema by preparing then discarding some query against the
+** database, or calling sqlite3_table_column_metadata(), ignoring any
+** errors. This step is only necessary if the application desires to keep
+** the database in WAL mode after the reset if it was in WAL mode before
+** the reset.
+**
+** Because resetting a database is destructive and irreversible, the
+** process requires the use of this obscure API and multiple steps to help
+** ensure that it does not happen by accident.
+**
+**
+*/
+#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */
+#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
+#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
+#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
+#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
+#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
+#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */
+#define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */
+#define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */
+#define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */
+#define SQLITE_DBCONFIG_MAX 1009 /* Largest DBCONFIG */
+
+/*
+** CAPI3REF: Enable Or Disable Extended Result Codes
+** METHOD: sqlite3
+**
+** ^The sqlite3_extended_result_codes() routine enables or disables the
+** [extended result codes] feature of SQLite. ^The extended result
+** codes are disabled by default for historical compatibility.
+*/
+SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
+
+/*
+** CAPI3REF: Last Insert Rowid
+** METHOD: sqlite3
+**
+** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
+** has a unique 64-bit signed
+** integer key called the [ROWID | "rowid"]. ^The rowid is always available
+** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
+** names are not also used by explicitly declared columns. ^If
+** the table has a column of type [INTEGER PRIMARY KEY] then that column
+** is another alias for the rowid.
+**
+** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
+** the most recent successful [INSERT] into a rowid table or [virtual table]
+** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
+** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
+** on the database connection D, then sqlite3_last_insert_rowid(D) returns
+** zero.
+**
+** As well as being set automatically as rows are inserted into database
+** tables, the value returned by this function may be set explicitly by
+** [sqlite3_set_last_insert_rowid()]
+**
+** Some virtual table implementations may INSERT rows into rowid tables as
+** part of committing a transaction (e.g. to flush data accumulated in memory
+** to disk). In this case subsequent calls to this function return the rowid
+** associated with these internal INSERT operations, which leads to
+** unintuitive results. Virtual table implementations that do write to rowid
+** tables in this way can avoid this problem by restoring the original
+** rowid value using [sqlite3_set_last_insert_rowid()] before returning
+** control to the user.
+**
+** ^(If an [INSERT] occurs within a trigger then this routine will
+** return the [rowid] of the inserted row as long as the trigger is
+** running. Once the trigger program ends, the value returned
+** by this routine reverts to what it was before the trigger was fired.)^
+**
+** ^An [INSERT] that fails due to a constraint violation is not a
+** successful [INSERT] and does not change the value returned by this
+** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
+** and INSERT OR ABORT make no changes to the return value of this
+** routine when their insertion fails. ^(When INSERT OR REPLACE
+** encounters a constraint violation, it does not fail. The
+** INSERT continues to completion after deleting rows that caused
+** the constraint problem so INSERT OR REPLACE will always change
+** the return value of this interface.)^
+**
+** ^For the purposes of this routine, an [INSERT] is considered to
+** be successful even if it is subsequently rolled back.
+**
+** This function is accessible to SQL statements via the
+** [last_insert_rowid() SQL function].
+**
+** If a separate thread performs a new [INSERT] on the same
+** database connection while the [sqlite3_last_insert_rowid()]
+** function is running and thus changes the last insert [rowid],
+** then the value returned by [sqlite3_last_insert_rowid()] is
+** unpredictable and might not equal either the old or the new
+** last insert [rowid].
+*/
+SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
+
+/*
+** CAPI3REF: Set the Last Insert Rowid value.
+** METHOD: sqlite3
+**
+** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
+** set the value returned by calling sqlite3_last_insert_rowid(D) to R
+** without inserting a row into the database.
+*/
+SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
+
+/*
+** CAPI3REF: Count The Number Of Rows Modified
+** METHOD: sqlite3
+**
+** ^This function returns the number of rows modified, inserted or
+** deleted by the most recently completed INSERT, UPDATE or DELETE
+** statement on the database connection specified by the only parameter.
+** ^Executing any other type of SQL statement does not modify the value
+** returned by this function.
+**
+** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
+** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
+** [foreign key actions] or [REPLACE] constraint resolution are not counted.
+**
+** Changes to a view that are intercepted by
+** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
+** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
+** DELETE statement run on a view is always zero. Only changes made to real
+** tables are counted.
+**
+** Things are more complicated if the sqlite3_changes() function is
+** executed while a trigger program is running. This may happen if the
+** program uses the [changes() SQL function], or if some other callback
+** function invokes sqlite3_changes() directly. Essentially:
+**
+**
+**
^(Before entering a trigger program the value returned by
+** sqlite3_changes() function is saved. After the trigger program
+** has finished, the original value is restored.)^
+**
+**
^(Within a trigger program each INSERT, UPDATE and DELETE
+** statement sets the value returned by sqlite3_changes()
+** upon completion as normal. Of course, this value will not include
+** any changes performed by sub-triggers, as the sqlite3_changes()
+** value will be saved and restored after each sub-trigger has run.)^
+**
+**
+** ^This means that if the changes() SQL function (or similar) is used
+** by the first INSERT, UPDATE or DELETE statement within a trigger, it
+** returns the value as set when the calling statement began executing.
+** ^If it is used by the second or subsequent such statement within a trigger
+** program, the value returned reflects the number of rows modified by the
+** previous INSERT, UPDATE or DELETE statement within the same trigger.
+**
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_changes()] is running then the value returned
+** is unpredictable and not meaningful.
+**
+** See also:
+**
+**
the [sqlite3_total_changes()] interface
+**
the [count_changes pragma]
+**
the [changes() SQL function]
+**
the [data_version pragma]
+**
+*/
+SQLITE_API int sqlite3_changes(sqlite3*);
+
+/*
+** CAPI3REF: Total Number Of Rows Modified
+** METHOD: sqlite3
+**
+** ^This function returns the total number of rows inserted, modified or
+** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
+** since the database connection was opened, including those executed as
+** part of trigger programs. ^Executing any other type of SQL statement
+** does not affect the value returned by sqlite3_total_changes().
+**
+** ^Changes made as part of [foreign key actions] are included in the
+** count, but those made as part of REPLACE constraint resolution are
+** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
+** are not counted.
+**
+** This the [sqlite3_total_changes(D)] interface only reports the number
+** of rows that changed due to SQL statement run against database
+** connection D. Any changes by other database connections are ignored.
+** To detect changes against a database file from other database
+** connections use the [PRAGMA data_version] command or the
+** [SQLITE_FCNTL_DATA_VERSION] [file control].
+**
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_total_changes()] is running then the value
+** returned is unpredictable and not meaningful.
+**
+** See also:
+**
+**
the [sqlite3_changes()] interface
+**
the [count_changes pragma]
+**
the [changes() SQL function]
+**
the [data_version pragma]
+**
the [SQLITE_FCNTL_DATA_VERSION] [file control]
+**
+*/
+SQLITE_API int sqlite3_total_changes(sqlite3*);
+
+/*
+** CAPI3REF: Interrupt A Long-Running Query
+** METHOD: sqlite3
+**
+** ^This function causes any pending database operation to abort and
+** return at its earliest opportunity. This routine is typically
+** called in response to a user action such as pressing "Cancel"
+** or Ctrl-C where the user wants a long query operation to halt
+** immediately.
+**
+** ^It is safe to call this routine from a thread different from the
+** thread that is currently running the database operation. But it
+** is not safe to call this routine with a [database connection] that
+** is closed or might close before sqlite3_interrupt() returns.
+**
+** ^If an SQL operation is very nearly finished at the time when
+** sqlite3_interrupt() is called, then it might not have an opportunity
+** to be interrupted and might continue to completion.
+**
+** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
+** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
+** that is inside an explicit transaction, then the entire transaction
+** will be rolled back automatically.
+**
+** ^The sqlite3_interrupt(D) call is in effect until all currently running
+** SQL statements on [database connection] D complete. ^Any new SQL statements
+** that are started after the sqlite3_interrupt() call and before the
+** running statements reaches zero are interrupted as if they had been
+** running prior to the sqlite3_interrupt() call. ^New SQL statements
+** that are started after the running statement count reaches zero are
+** not effected by the sqlite3_interrupt().
+** ^A call to sqlite3_interrupt(D) that occurs when there are no running
+** SQL statements is a no-op and has no effect on SQL statements
+** that are started after the sqlite3_interrupt() call returns.
+*/
+SQLITE_API void sqlite3_interrupt(sqlite3*);
+
+/*
+** CAPI3REF: Determine If An SQL Statement Is Complete
+**
+** These routines are useful during command-line input to determine if the
+** currently entered text seems to form a complete SQL statement or
+** if additional input is needed before sending the text into
+** SQLite for parsing. ^These routines return 1 if the input string
+** appears to be a complete SQL statement. ^A statement is judged to be
+** complete if it ends with a semicolon token and is not a prefix of a
+** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
+** string literals or quoted identifier names or comments are not
+** independent tokens (they are part of the token in which they are
+** embedded) and thus do not count as a statement terminator. ^Whitespace
+** and comments that follow the final semicolon are ignored.
+**
+** ^These routines return 0 if the statement is incomplete. ^If a
+** memory allocation fails, then SQLITE_NOMEM is returned.
+**
+** ^These routines do not parse the SQL statements thus
+** will not detect syntactically incorrect SQL.
+**
+** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
+** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
+** automatically by sqlite3_complete16(). If that initialization fails,
+** then the return value from sqlite3_complete16() will be non-zero
+** regardless of whether or not the input SQL is complete.)^
+**
+** The input to [sqlite3_complete()] must be a zero-terminated
+** UTF-8 string.
+**
+** The input to [sqlite3_complete16()] must be a zero-terminated
+** UTF-16 string in native byte order.
+*/
+SQLITE_API int sqlite3_complete(const char *sql);
+SQLITE_API int sqlite3_complete16(const void *sql);
+
+/*
+** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
+** KEYWORDS: {busy-handler callback} {busy handler}
+** METHOD: sqlite3
+**
+** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
+** that might be invoked with argument P whenever
+** an attempt is made to access a database table associated with
+** [database connection] D when another thread
+** or process has the table locked.
+** The sqlite3_busy_handler() interface is used to implement
+** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
+**
+** ^If the busy callback is NULL, then [SQLITE_BUSY]
+** is returned immediately upon encountering the lock. ^If the busy callback
+** is not NULL, then the callback might be invoked with two arguments.
+**
+** ^The first argument to the busy handler is a copy of the void* pointer which
+** is the third argument to sqlite3_busy_handler(). ^The second argument to
+** the busy handler callback is the number of times that the busy handler has
+** been invoked previously for the same locking event. ^If the
+** busy callback returns 0, then no additional attempts are made to
+** access the database and [SQLITE_BUSY] is returned
+** to the application.
+** ^If the callback returns non-zero, then another attempt
+** is made to access the database and the cycle repeats.
+**
+** The presence of a busy handler does not guarantee that it will be invoked
+** when there is lock contention. ^If SQLite determines that invoking the busy
+** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
+** to the application instead of invoking the
+** busy handler.
+** Consider a scenario where one process is holding a read lock that
+** it is trying to promote to a reserved lock and
+** a second process is holding a reserved lock that it is trying
+** to promote to an exclusive lock. The first process cannot proceed
+** because it is blocked by the second and the second process cannot
+** proceed because it is blocked by the first. If both processes
+** invoke the busy handlers, neither will make any progress. Therefore,
+** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
+** will induce the first process to release its read lock and allow
+** the second process to proceed.
+**
+** ^The default busy callback is NULL.
+**
+** ^(There can only be a single busy handler defined for each
+** [database connection]. Setting a new busy handler clears any
+** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
+** or evaluating [PRAGMA busy_timeout=N] will change the
+** busy handler and thus clear any previously set busy handler.
+**
+** The busy callback should not take any actions which modify the
+** database connection that invoked the busy handler. In other words,
+** the busy handler is not reentrant. Any such actions
+** result in undefined behavior.
+**
+** A busy handler must not close the database connection
+** or [prepared statement] that invoked the busy handler.
+*/
+SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
+
+/*
+** CAPI3REF: Set A Busy Timeout
+** METHOD: sqlite3
+**
+** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
+** for a specified amount of time when a table is locked. ^The handler
+** will sleep multiple times until at least "ms" milliseconds of sleeping
+** have accumulated. ^After at least "ms" milliseconds of sleeping,
+** the handler returns 0 which causes [sqlite3_step()] to return
+** [SQLITE_BUSY].
+**
+** ^Calling this routine with an argument less than or equal to zero
+** turns off all busy handlers.
+**
+** ^(There can only be a single busy handler for a particular
+** [database connection] at any given moment. If another busy handler
+** was defined (using [sqlite3_busy_handler()]) prior to calling
+** this routine, that other busy handler is cleared.)^
+**
+** See also: [PRAGMA busy_timeout]
+*/
+SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
+
+/*
+** CAPI3REF: Convenience Routines For Running Queries
+** METHOD: sqlite3
+**
+** This is a legacy interface that is preserved for backwards compatibility.
+** Use of this interface is not recommended.
+**
+** Definition: A result table is memory data structure created by the
+** [sqlite3_get_table()] interface. A result table records the
+** complete query results from one or more queries.
+**
+** The table conceptually has a number of rows and columns. But
+** these numbers are not part of the result table itself. These
+** numbers are obtained separately. Let N be the number of rows
+** and M be the number of columns.
+**
+** A result table is an array of pointers to zero-terminated UTF-8 strings.
+** There are (N+1)*M elements in the array. The first M pointers point
+** to zero-terminated strings that contain the names of the columns.
+** The remaining entries all point to query results. NULL values result
+** in NULL pointers. All other values are in their UTF-8 zero-terminated
+** string representation as returned by [sqlite3_column_text()].
+**
+** A result table might consist of one or more memory allocations.
+** It is not safe to pass a result table directly to [sqlite3_free()].
+** A result table should be deallocated using [sqlite3_free_table()].
+**
+** ^(As an example of the result table format, suppose a query result
+** is as follows:
+**
+**
+** Name | Age
+** -----------------------
+** Alice | 43
+** Bob | 28
+** Cindy | 21
+**
+**
+** There are two column (M==2) and three rows (N==3). Thus the
+** result table has 8 entries. Suppose the result table is stored
+** in an array names azResult. Then azResult holds this content:
+**
+**
)^
+**
+** ^The sqlite3_get_table() function evaluates one or more
+** semicolon-separated SQL statements in the zero-terminated UTF-8
+** string of its 2nd parameter and returns a result table to the
+** pointer given in its 3rd parameter.
+**
+** After the application has finished with the result from sqlite3_get_table(),
+** it must pass the result table pointer to sqlite3_free_table() in order to
+** release the memory that was malloced. Because of the way the
+** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
+** function must not try to call [sqlite3_free()] directly. Only
+** [sqlite3_free_table()] is able to release the memory properly and safely.
+**
+** The sqlite3_get_table() interface is implemented as a wrapper around
+** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
+** to any internal data structures of SQLite. It uses only the public
+** interface defined here. As a consequence, errors that occur in the
+** wrapper layer outside of the internal [sqlite3_exec()] call are not
+** reflected in subsequent calls to [sqlite3_errcode()] or
+** [sqlite3_errmsg()].
+*/
+SQLITE_API int sqlite3_get_table(
+ sqlite3 *db, /* An open database */
+ const char *zSql, /* SQL to be evaluated */
+ char ***pazResult, /* Results of the query */
+ int *pnRow, /* Number of result rows written here */
+ int *pnColumn, /* Number of result columns written here */
+ char **pzErrmsg /* Error msg written here */
+);
+SQLITE_API void sqlite3_free_table(char **result);
+
+/*
+** CAPI3REF: Formatted String Printing Functions
+**
+** These routines are work-alikes of the "printf()" family of functions
+** from the standard C library.
+** These routines understand most of the common formatting options from
+** the standard library printf()
+** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
+** See the [built-in printf()] documentation for details.
+**
+** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
+** results into memory obtained from [sqlite3_malloc64()].
+** The strings returned by these two routines should be
+** released by [sqlite3_free()]. ^Both routines return a
+** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
+** memory to hold the resulting string.
+**
+** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
+** the standard C library. The result is written into the
+** buffer supplied as the second parameter whose size is given by
+** the first parameter. Note that the order of the
+** first two parameters is reversed from snprintf().)^ This is an
+** historical accident that cannot be fixed without breaking
+** backwards compatibility. ^(Note also that sqlite3_snprintf()
+** returns a pointer to its buffer instead of the number of
+** characters actually written into the buffer.)^ We admit that
+** the number of characters written would be a more useful return
+** value but we cannot change the implementation of sqlite3_snprintf()
+** now without breaking compatibility.
+**
+** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
+** guarantees that the buffer is always zero-terminated. ^The first
+** parameter "n" is the total size of the buffer, including space for
+** the zero terminator. So the longest string that can be completely
+** written will be n-1 characters.
+**
+** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
+**
+** See also: [built-in printf()], [printf() SQL function]
+*/
+SQLITE_API char *sqlite3_mprintf(const char*,...);
+SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
+SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
+SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
+
+/*
+** CAPI3REF: Memory Allocation Subsystem
+**
+** The SQLite core uses these three routines for all of its own
+** internal memory allocation needs. "Core" in the previous sentence
+** does not include operating-system specific VFS implementation. The
+** Windows VFS uses native malloc() and free() for some operations.
+**
+** ^The sqlite3_malloc() routine returns a pointer to a block
+** of memory at least N bytes in length, where N is the parameter.
+** ^If sqlite3_malloc() is unable to obtain sufficient free
+** memory, it returns a NULL pointer. ^If the parameter N to
+** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
+** a NULL pointer.
+**
+** ^The sqlite3_malloc64(N) routine works just like
+** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
+** of a signed 32-bit integer.
+**
+** ^Calling sqlite3_free() with a pointer previously returned
+** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
+** that it might be reused. ^The sqlite3_free() routine is
+** a no-op if is called with a NULL pointer. Passing a NULL pointer
+** to sqlite3_free() is harmless. After being freed, memory
+** should neither be read nor written. Even reading previously freed
+** memory might result in a segmentation fault or other severe error.
+** Memory corruption, a segmentation fault, or other severe error
+** might result if sqlite3_free() is called with a non-NULL pointer that
+** was not obtained from sqlite3_malloc() or sqlite3_realloc().
+**
+** ^The sqlite3_realloc(X,N) interface attempts to resize a
+** prior memory allocation X to be at least N bytes.
+** ^If the X parameter to sqlite3_realloc(X,N)
+** is a NULL pointer then its behavior is identical to calling
+** sqlite3_malloc(N).
+** ^If the N parameter to sqlite3_realloc(X,N) is zero or
+** negative then the behavior is exactly the same as calling
+** sqlite3_free(X).
+** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
+** of at least N bytes in size or NULL if insufficient memory is available.
+** ^If M is the size of the prior allocation, then min(N,M) bytes
+** of the prior allocation are copied into the beginning of buffer returned
+** by sqlite3_realloc(X,N) and the prior allocation is freed.
+** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
+** prior allocation is not freed.
+**
+** ^The sqlite3_realloc64(X,N) interfaces works the same as
+** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
+** of a 32-bit signed integer.
+**
+** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
+** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
+** sqlite3_msize(X) returns the size of that memory allocation in bytes.
+** ^The value returned by sqlite3_msize(X) might be larger than the number
+** of bytes requested when X was allocated. ^If X is a NULL pointer then
+** sqlite3_msize(X) returns zero. If X points to something that is not
+** the beginning of memory allocation, or if it points to a formerly
+** valid memory allocation that has now been freed, then the behavior
+** of sqlite3_msize(X) is undefined and possibly harmful.
+**
+** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
+** sqlite3_malloc64(), and sqlite3_realloc64()
+** is always aligned to at least an 8 byte boundary, or to a
+** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
+** option is used.
+**
+** In SQLite version 3.5.0 and 3.5.1, it was possible to define
+** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
+** implementation of these routines to be omitted. That capability
+** is no longer provided. Only built-in memory allocators can be used.
+**
+** Prior to SQLite version 3.7.10, the Windows OS interface layer called
+** the system malloc() and free() directly when converting
+** filenames between the UTF-8 encoding used by SQLite
+** and whatever filename encoding is used by the particular Windows
+** installation. Memory allocation errors were detected, but
+** they were reported back as [SQLITE_CANTOPEN] or
+** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
+**
+** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
+** must be either NULL or else pointers obtained from a prior
+** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
+** not yet been released.
+**
+** The application must not read or write any part of
+** a block of memory after it has been released using
+** [sqlite3_free()] or [sqlite3_realloc()].
+*/
+SQLITE_API void *sqlite3_malloc(int);
+SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
+SQLITE_API void *sqlite3_realloc(void*, int);
+SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
+SQLITE_API void sqlite3_free(void*);
+SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
+
+/*
+** CAPI3REF: Memory Allocator Statistics
+**
+** SQLite provides these two interfaces for reporting on the status
+** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
+** routines, which form the built-in memory allocation subsystem.
+**
+** ^The [sqlite3_memory_used()] routine returns the number of bytes
+** of memory currently outstanding (malloced but not freed).
+** ^The [sqlite3_memory_highwater()] routine returns the maximum
+** value of [sqlite3_memory_used()] since the high-water mark
+** was last reset. ^The values returned by [sqlite3_memory_used()] and
+** [sqlite3_memory_highwater()] include any overhead
+** added by SQLite in its implementation of [sqlite3_malloc()],
+** but not overhead added by the any underlying system library
+** routines that [sqlite3_malloc()] may call.
+**
+** ^The memory high-water mark is reset to the current value of
+** [sqlite3_memory_used()] if and only if the parameter to
+** [sqlite3_memory_highwater()] is true. ^The value returned
+** by [sqlite3_memory_highwater(1)] is the high-water mark
+** prior to the reset.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
+SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
+
+/*
+** CAPI3REF: Pseudo-Random Number Generator
+**
+** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
+** select random [ROWID | ROWIDs] when inserting new records into a table that
+** already uses the largest possible [ROWID]. The PRNG is also used for
+** the build-in random() and randomblob() SQL functions. This interface allows
+** applications to access the same PRNG for other purposes.
+**
+** ^A call to this routine stores N bytes of randomness into buffer P.
+** ^The P parameter can be a NULL pointer.
+**
+** ^If this routine has not been previously called or if the previous
+** call had N less than one or a NULL pointer for P, then the PRNG is
+** seeded using randomness obtained from the xRandomness method of
+** the default [sqlite3_vfs] object.
+** ^If the previous call to this routine had an N of 1 or more and a
+** non-NULL P then the pseudo-randomness is generated
+** internally and without recourse to the [sqlite3_vfs] xRandomness
+** method.
+*/
+SQLITE_API void sqlite3_randomness(int N, void *P);
+
+/*
+** CAPI3REF: Compile-Time Authorization Callbacks
+** METHOD: sqlite3
+** KEYWORDS: {authorizer callback}
+**
+** ^This routine registers an authorizer callback with a particular
+** [database connection], supplied in the first argument.
+** ^The authorizer callback is invoked as SQL statements are being compiled
+** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
+** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
+** and [sqlite3_prepare16_v3()]. ^At various
+** points during the compilation process, as logic is being created
+** to perform various actions, the authorizer callback is invoked to
+** see if those actions are allowed. ^The authorizer callback should
+** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
+** specific action but allow the SQL statement to continue to be
+** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
+** rejected with an error. ^If the authorizer callback returns
+** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
+** then the [sqlite3_prepare_v2()] or equivalent call that triggered
+** the authorizer will fail with an error message.
+**
+** When the callback returns [SQLITE_OK], that means the operation
+** requested is ok. ^When the callback returns [SQLITE_DENY], the
+** [sqlite3_prepare_v2()] or equivalent call that triggered the
+** authorizer will fail with an error message explaining that
+** access is denied.
+**
+** ^The first parameter to the authorizer callback is a copy of the third
+** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
+** to the callback is an integer [SQLITE_COPY | action code] that specifies
+** the particular action to be authorized. ^The third through sixth parameters
+** to the callback are either NULL pointers or zero-terminated strings
+** that contain additional details about the action to be authorized.
+** Applications must always be prepared to encounter a NULL pointer in any
+** of the third through the sixth parameters of the authorization callback.
+**
+** ^If the action code is [SQLITE_READ]
+** and the callback returns [SQLITE_IGNORE] then the
+** [prepared statement] statement is constructed to substitute
+** a NULL value in place of the table column that would have
+** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
+** return can be used to deny an untrusted user access to individual
+** columns of a table.
+** ^When a table is referenced by a [SELECT] but no column values are
+** extracted from that table (for example in a query like
+** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
+** is invoked once for that table with a column name that is an empty string.
+** ^If the action code is [SQLITE_DELETE] and the callback returns
+** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
+** [truncate optimization] is disabled and all rows are deleted individually.
+**
+** An authorizer is used when [sqlite3_prepare | preparing]
+** SQL statements from an untrusted source, to ensure that the SQL statements
+** do not try to access data they are not allowed to see, or that they do not
+** try to execute malicious statements that damage the database. For
+** example, an application may allow a user to enter arbitrary
+** SQL queries for evaluation by a database. But the application does
+** not want the user to be able to make arbitrary changes to the
+** database. An authorizer could then be put in place while the
+** user-entered SQL is being [sqlite3_prepare | prepared] that
+** disallows everything except [SELECT] statements.
+**
+** Applications that need to process SQL from untrusted sources
+** might also consider lowering resource limits using [sqlite3_limit()]
+** and limiting database size using the [max_page_count] [PRAGMA]
+** in addition to using an authorizer.
+**
+** ^(Only a single authorizer can be in place on a database connection
+** at a time. Each call to sqlite3_set_authorizer overrides the
+** previous call.)^ ^Disable the authorizer by installing a NULL callback.
+** The authorizer is disabled by default.
+**
+** The authorizer callback must not do anything that will modify
+** the database connection that invoked the authorizer callback.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
+** statement might be re-prepared during [sqlite3_step()] due to a
+** schema change. Hence, the application should ensure that the
+** correct authorizer callback remains in place during the [sqlite3_step()].
+**
+** ^Note that the authorizer callback is invoked only during
+** [sqlite3_prepare()] or its variants. Authorization is not
+** performed during statement evaluation in [sqlite3_step()], unless
+** as stated in the previous paragraph, sqlite3_step() invokes
+** sqlite3_prepare_v2() to reprepare a statement after a schema change.
+*/
+SQLITE_API int sqlite3_set_authorizer(
+ sqlite3*,
+ int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
+ void *pUserData
+);
+
+/*
+** CAPI3REF: Authorizer Return Codes
+**
+** The [sqlite3_set_authorizer | authorizer callback function] must
+** return either [SQLITE_OK] or one of these two constants in order
+** to signal SQLite whether or not the action is permitted. See the
+** [sqlite3_set_authorizer | authorizer documentation] for additional
+** information.
+**
+** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
+** returned from the [sqlite3_vtab_on_conflict()] interface.
+*/
+#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
+#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
+
+/*
+** CAPI3REF: Authorizer Action Codes
+**
+** The [sqlite3_set_authorizer()] interface registers a callback function
+** that is invoked to authorize certain SQL statement actions. The
+** second parameter to the callback is an integer code that specifies
+** what action is being authorized. These are the integer action codes that
+** the authorizer callback may be passed.
+**
+** These action code values signify what kind of operation is to be
+** authorized. The 3rd and 4th parameters to the authorization
+** callback function will be parameters or NULL depending on which of these
+** codes is used as the second parameter. ^(The 5th parameter to the
+** authorizer callback is the name of the database ("main", "temp",
+** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
+** is the name of the inner-most trigger or view that is responsible for
+** the access attempt or NULL if this access attempt is directly from
+** top-level SQL code.
+*/
+/******************************************* 3rd ************ 4th ***********/
+#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
+#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
+#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
+#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
+#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
+#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
+#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
+#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
+#define SQLITE_DELETE 9 /* Table Name NULL */
+#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
+#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
+#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
+#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
+#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
+#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
+#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
+#define SQLITE_DROP_VIEW 17 /* View Name NULL */
+#define SQLITE_INSERT 18 /* Table Name NULL */
+#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
+#define SQLITE_READ 20 /* Table Name Column Name */
+#define SQLITE_SELECT 21 /* NULL NULL */
+#define SQLITE_TRANSACTION 22 /* Operation NULL */
+#define SQLITE_UPDATE 23 /* Table Name Column Name */
+#define SQLITE_ATTACH 24 /* Filename NULL */
+#define SQLITE_DETACH 25 /* Database Name NULL */
+#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
+#define SQLITE_REINDEX 27 /* Index Name NULL */
+#define SQLITE_ANALYZE 28 /* Table Name NULL */
+#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
+#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
+#define SQLITE_FUNCTION 31 /* NULL Function Name */
+#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
+#define SQLITE_COPY 0 /* No longer used */
+#define SQLITE_RECURSIVE 33 /* NULL NULL */
+
+/*
+** CAPI3REF: Tracing And Profiling Functions
+** METHOD: sqlite3
+**
+** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
+** instead of the routines described here.
+**
+** These routines register callback functions that can be used for
+** tracing and profiling the execution of SQL statements.
+**
+** ^The callback function registered by sqlite3_trace() is invoked at
+** various times when an SQL statement is being run by [sqlite3_step()].
+** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
+** SQL statement text as the statement first begins executing.
+** ^(Additional sqlite3_trace() callbacks might occur
+** as each triggered subprogram is entered. The callbacks for triggers
+** contain a UTF-8 SQL comment that identifies the trigger.)^
+**
+** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
+** the length of [bound parameter] expansion in the output of sqlite3_trace().
+**
+** ^The callback function registered by sqlite3_profile() is invoked
+** as each SQL statement finishes. ^The profile callback contains
+** the original statement text and an estimate of wall-clock time
+** of how long that statement took to run. ^The profile callback
+** time is in units of nanoseconds, however the current implementation
+** is only capable of millisecond resolution so the six least significant
+** digits in the time are meaningless. Future versions of SQLite
+** might provide greater resolution on the profiler callback. The
+** sqlite3_profile() function is considered experimental and is
+** subject to change in future versions of SQLite.
+*/
+SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
+ void(*xTrace)(void*,const char*), void*);
+SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
+ void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
+
+/*
+** CAPI3REF: SQL Trace Event Codes
+** KEYWORDS: SQLITE_TRACE
+**
+** These constants identify classes of events that can be monitored
+** using the [sqlite3_trace_v2()] tracing logic. The M argument
+** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
+** the following constants. ^The first argument to the trace callback
+** is one of the following constants.
+**
+** New tracing constants may be added in future releases.
+**
+** ^A trace callback has four arguments: xCallback(T,C,P,X).
+** ^The T argument is one of the integer type codes above.
+** ^The C argument is a copy of the context pointer passed in as the
+** fourth argument to [sqlite3_trace_v2()].
+** The P and X arguments are pointers whose meanings depend on T.
+**
+**
+** [[SQLITE_TRACE_STMT]]
SQLITE_TRACE_STMT
+**
^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
+** first begins running and possibly at other times during the
+** execution of the prepared statement, such as at the start of each
+** trigger subprogram. ^The P argument is a pointer to the
+** [prepared statement]. ^The X argument is a pointer to a string which
+** is the unexpanded SQL text of the prepared statement or an SQL comment
+** that indicates the invocation of a trigger. ^The callback can compute
+** the same text that would have been returned by the legacy [sqlite3_trace()]
+** interface by using the X argument when X begins with "--" and invoking
+** [sqlite3_expanded_sql(P)] otherwise.
+**
+** [[SQLITE_TRACE_PROFILE]]
SQLITE_TRACE_PROFILE
+**
^An SQLITE_TRACE_PROFILE callback provides approximately the same
+** information as is provided by the [sqlite3_profile()] callback.
+** ^The P argument is a pointer to the [prepared statement] and the
+** X argument points to a 64-bit integer which is the estimated of
+** the number of nanosecond that the prepared statement took to run.
+** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
+**
+** [[SQLITE_TRACE_ROW]]
SQLITE_TRACE_ROW
+**
^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
+** statement generates a single row of result.
+** ^The P argument is a pointer to the [prepared statement] and the
+** X argument is unused.
+**
+** [[SQLITE_TRACE_CLOSE]]
SQLITE_TRACE_CLOSE
+**
^An SQLITE_TRACE_CLOSE callback is invoked when a database
+** connection closes.
+** ^The P argument is a pointer to the [database connection] object
+** and the X argument is unused.
+**
+*/
+#define SQLITE_TRACE_STMT 0x01
+#define SQLITE_TRACE_PROFILE 0x02
+#define SQLITE_TRACE_ROW 0x04
+#define SQLITE_TRACE_CLOSE 0x08
+
+/*
+** CAPI3REF: SQL Trace Hook
+** METHOD: sqlite3
+**
+** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
+** function X against [database connection] D, using property mask M
+** and context pointer P. ^If the X callback is
+** NULL or if the M mask is zero, then tracing is disabled. The
+** M argument should be the bitwise OR-ed combination of
+** zero or more [SQLITE_TRACE] constants.
+**
+** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides
+** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().
+**
+** ^The X callback is invoked whenever any of the events identified by
+** mask M occur. ^The integer return value from the callback is currently
+** ignored, though this may change in future releases. Callback
+** implementations should return zero to ensure future compatibility.
+**
+** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
+** ^The T argument is one of the [SQLITE_TRACE]
+** constants to indicate why the callback was invoked.
+** ^The C argument is a copy of the context pointer.
+** The P and X arguments are pointers whose meanings depend on T.
+**
+** The sqlite3_trace_v2() interface is intended to replace the legacy
+** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
+** are deprecated.
+*/
+SQLITE_API int sqlite3_trace_v2(
+ sqlite3*,
+ unsigned uMask,
+ int(*xCallback)(unsigned,void*,void*,void*),
+ void *pCtx
+);
+
+/*
+** CAPI3REF: Query Progress Callbacks
+** METHOD: sqlite3
+**
+** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
+** function X to be invoked periodically during long running calls to
+** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
+** database connection D. An example use for this
+** interface is to keep a GUI updated during a large query.
+**
+** ^The parameter P is passed through as the only parameter to the
+** callback function X. ^The parameter N is the approximate number of
+** [virtual machine instructions] that are evaluated between successive
+** invocations of the callback X. ^If N is less than one then the progress
+** handler is disabled.
+**
+** ^Only a single progress handler may be defined at one time per
+** [database connection]; setting a new progress handler cancels the
+** old one. ^Setting parameter X to NULL disables the progress handler.
+** ^The progress handler is also disabled by setting N to a value less
+** than 1.
+**
+** ^If the progress callback returns non-zero, the operation is
+** interrupted. This feature can be used to implement a
+** "Cancel" button on a GUI progress dialog box.
+**
+** The progress handler callback must not do anything that will modify
+** the database connection that invoked the progress handler.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+*/
+SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
+
+/*
+** CAPI3REF: Opening A New Database Connection
+** CONSTRUCTOR: sqlite3
+**
+** ^These routines open an SQLite database file as specified by the
+** filename argument. ^The filename argument is interpreted as UTF-8 for
+** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
+** order for sqlite3_open16(). ^(A [database connection] handle is usually
+** returned in *ppDb, even if an error occurs. The only exception is that
+** if SQLite is unable to allocate memory to hold the [sqlite3] object,
+** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
+** object.)^ ^(If the database is opened (and/or created) successfully, then
+** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
+** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
+** an English language description of the error following a failure of any
+** of the sqlite3_open() routines.
+**
+** ^The default encoding will be UTF-8 for databases created using
+** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases
+** created using sqlite3_open16() will be UTF-16 in the native byte order.
+**
+** Whether or not an error occurs when it is opened, resources
+** associated with the [database connection] handle should be released by
+** passing it to [sqlite3_close()] when it is no longer required.
+**
+** The sqlite3_open_v2() interface works like sqlite3_open()
+** except that it accepts two additional parameters for additional control
+** over the new database connection. ^(The flags parameter to
+** sqlite3_open_v2() can take one of
+** the following three values, optionally combined with the
+** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
+** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
+**
+**
+** ^(
[SQLITE_OPEN_READONLY]
+**
The database is opened in read-only mode. If the database does not
+** already exist, an error is returned.
)^
+**
+** ^(
[SQLITE_OPEN_READWRITE]
+**
The database is opened for reading and writing if possible, or reading
+** only if the file is write protected by the operating system. In either
+** case the database must already exist, otherwise an error is returned.
)^
+**
+** ^(
[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
+**
The database is opened for reading and writing, and is created if
+** it does not already exist. This is the behavior that is always used for
+** sqlite3_open() and sqlite3_open16().
)^
+**
+**
+** If the 3rd parameter to sqlite3_open_v2() is not one of the
+** combinations shown above optionally combined with other
+** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
+** then the behavior is undefined.
+**
+** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
+** opens in the multi-thread [threading mode] as long as the single-thread
+** mode has not been set at compile-time or start-time. ^If the
+** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
+** in the serialized [threading mode] unless single-thread was
+** previously selected at compile-time or start-time.
+** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
+** eligible to use [shared cache mode], regardless of whether or not shared
+** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
+** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
+** participate in [shared cache mode] even if it is enabled.
+**
+** ^The fourth parameter to sqlite3_open_v2() is the name of the
+** [sqlite3_vfs] object that defines the operating system interface that
+** the new database connection should use. ^If the fourth parameter is
+** a NULL pointer then the default [sqlite3_vfs] object is used.
+**
+** ^If the filename is ":memory:", then a private, temporary in-memory database
+** is created for the connection. ^This in-memory database will vanish when
+** the database connection is closed. Future versions of SQLite might
+** make use of additional special filenames that begin with the ":" character.
+** It is recommended that when a database filename actually does begin with
+** a ":" character you should prefix the filename with a pathname such as
+** "./" to avoid ambiguity.
+**
+** ^If the filename is an empty string, then a private, temporary
+** on-disk database will be created. ^This private database will be
+** automatically deleted as soon as the database connection is closed.
+**
+** [[URI filenames in sqlite3_open()]]
URI Filenames
+**
+** ^If [URI filename] interpretation is enabled, and the filename argument
+** begins with "file:", then the filename is interpreted as a URI. ^URI
+** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
+** set in the third argument to sqlite3_open_v2(), or if it has
+** been enabled globally using the [SQLITE_CONFIG_URI] option with the
+** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
+** URI filename interpretation is turned off
+** by default, but future releases of SQLite might enable URI filename
+** interpretation by default. See "[URI filenames]" for additional
+** information.
+**
+** URI filenames are parsed according to RFC 3986. ^If the URI contains an
+** authority, then it must be either an empty string or the string
+** "localhost". ^If the authority is not an empty string or "localhost", an
+** error is returned to the caller. ^The fragment component of a URI, if
+** present, is ignored.
+**
+** ^SQLite uses the path component of the URI as the name of the disk file
+** which contains the database. ^If the path begins with a '/' character,
+** then it is interpreted as an absolute path. ^If the path does not begin
+** with a '/' (meaning that the authority section is omitted from the URI)
+** then the path is interpreted as a relative path.
+** ^(On windows, the first component of an absolute path
+** is a drive specification (e.g. "C:").)^
+**
+** [[core URI query parameters]]
+** The query component of a URI may contain parameters that are interpreted
+** either by SQLite itself, or by a [VFS | custom VFS implementation].
+** SQLite and its built-in [VFSes] interpret the
+** following query parameters:
+**
+**
+**
vfs: ^The "vfs" parameter may be used to specify the name of
+** a VFS object that provides the operating system interface that should
+** be used to access the database file on disk. ^If this option is set to
+** an empty string the default VFS object is used. ^Specifying an unknown
+** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
+** present, then the VFS specified by the option takes precedence over
+** the value passed as the fourth parameter to sqlite3_open_v2().
+**
+**
mode: ^(The mode parameter may be set to either "ro", "rw",
+** "rwc", or "memory". Attempting to set it to any other value is
+** an error)^.
+** ^If "ro" is specified, then the database is opened for read-only
+** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
+** third argument to sqlite3_open_v2(). ^If the mode option is set to
+** "rw", then the database is opened for read-write (but not create)
+** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
+** been set. ^Value "rwc" is equivalent to setting both
+** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
+** set to "memory" then a pure [in-memory database] that never reads
+** or writes from disk is used. ^It is an error to specify a value for
+** the mode parameter that is less restrictive than that specified by
+** the flags passed in the third parameter to sqlite3_open_v2().
+**
+**
cache: ^The cache parameter may be set to either "shared" or
+** "private". ^Setting it to "shared" is equivalent to setting the
+** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
+** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
+** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
+** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
+** a URI filename, its value overrides any behavior requested by setting
+** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
+**
+**
psow: ^The psow parameter indicates whether or not the
+** [powersafe overwrite] property does or does not apply to the
+** storage media on which the database file resides.
+**
+**
nolock: ^The nolock parameter is a boolean query parameter
+** which if set disables file locking in rollback journal modes. This
+** is useful for accessing a database on a filesystem that does not
+** support locking. Caution: Database corruption might result if two
+** or more processes write to the same database and any one of those
+** processes uses nolock=1.
+**
+**
immutable: ^The immutable parameter is a boolean query
+** parameter that indicates that the database file is stored on
+** read-only media. ^When immutable is set, SQLite assumes that the
+** database file cannot be changed, even by a process with higher
+** privilege, and so the database is opened read-only and all locking
+** and change detection is disabled. Caution: Setting the immutable
+** property on a database file that does in fact change can result
+** in incorrect query results and/or [SQLITE_CORRUPT] errors.
+** See also: [SQLITE_IOCAP_IMMUTABLE].
+**
+**
+**
+** ^Specifying an unknown parameter in the query component of a URI is not an
+** error. Future versions of SQLite might understand additional query
+** parameters. See "[query parameters with special meaning to SQLite]" for
+** additional information.
+**
+** [[URI filename examples]]
URI filename examples
+**
+**
+**
URI filenames
Results
+**
file:data.db
+** Open the file "data.db" in the current directory.
+**
Windows only: Open the file "data.db" on fred's desktop on drive
+** C:. Note that the %20 escaping in this example is not strictly
+** necessary - space characters can be used literally
+** in URI filenames.
+**
file:data.db?mode=ro&cache=private
+** Open file "data.db" in the current directory for read-only access.
+** Regardless of whether or not shared-cache mode is enabled by
+** default, use a private cache.
+**
file:/home/fred/data.db?vfs=unix-dotfile
+** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
+** that uses dot-files in place of posix advisory locking.
+**
file:data.db?mode=readonly
+** An error. "readonly" is not a valid option for the "mode" parameter.
+**
+**
+** ^URI hexadecimal escape sequences (%HH) are supported within the path and
+** query components of a URI. A hexadecimal escape sequence consists of a
+** percent sign - "%" - followed by exactly two hexadecimal digits
+** specifying an octet value. ^Before the path or query components of a
+** URI filename are interpreted, they are encoded using UTF-8 and all
+** hexadecimal escape sequences replaced by a single byte containing the
+** corresponding octet. If this process generates an invalid UTF-8 encoding,
+** the results are undefined.
+**
+** Note to Windows users: The encoding used for the filename argument
+** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
+** codepage is currently defined. Filenames containing international
+** characters must be converted to UTF-8 prior to passing them into
+** sqlite3_open() or sqlite3_open_v2().
+**
+** Note to Windows Runtime users: The temporary directory must be set
+** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
+** features that require the use of temporary files may fail.
+**
+** See also: [sqlite3_temp_directory]
+*/
+SQLITE_API int sqlite3_open(
+ const char *filename, /* Database filename (UTF-8) */
+ sqlite3 **ppDb /* OUT: SQLite db handle */
+);
+SQLITE_API int sqlite3_open16(
+ const void *filename, /* Database filename (UTF-16) */
+ sqlite3 **ppDb /* OUT: SQLite db handle */
+);
+SQLITE_API int sqlite3_open_v2(
+ const char *filename, /* Database filename (UTF-8) */
+ sqlite3 **ppDb, /* OUT: SQLite db handle */
+ int flags, /* Flags */
+ const char *zVfs /* Name of VFS module to use */
+);
+
+/*
+** CAPI3REF: Obtain Values For URI Parameters
+**
+** These are utility routines, useful to VFS implementations, that check
+** to see if a database file was a URI that contained a specific query
+** parameter, and if so obtains the value of that query parameter.
+**
+** If F is the database filename pointer passed into the xOpen() method of
+** a VFS implementation when the flags parameter to xOpen() has one or
+** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
+** P is the name of the query parameter, then
+** sqlite3_uri_parameter(F,P) returns the value of the P
+** parameter if it exists or a NULL pointer if P does not appear as a
+** query parameter on F. If P is a query parameter of F
+** has no explicit value, then sqlite3_uri_parameter(F,P) returns
+** a pointer to an empty string.
+**
+** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
+** parameter and returns true (1) or false (0) according to the value
+** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
+** value of query parameter P is one of "yes", "true", or "on" in any
+** case or if the value begins with a non-zero number. The
+** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
+** query parameter P is one of "no", "false", or "off" in any case or
+** if the value begins with a numeric zero. If P is not a query
+** parameter on F or if the value of P is does not match any of the
+** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
+**
+** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
+** 64-bit signed integer and returns that integer, or D if P does not
+** exist. If the value of P is something other than an integer, then
+** zero is returned.
+**
+** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
+** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
+** is not a database file pathname pointer that SQLite passed into the xOpen
+** VFS method, then the behavior of this routine is undefined and probably
+** undesirable.
+*/
+SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
+SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
+SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
+
+
+/*
+** CAPI3REF: Error Codes And Messages
+** METHOD: sqlite3
+**
+** ^If the most recent sqlite3_* API call associated with
+** [database connection] D failed, then the sqlite3_errcode(D) interface
+** returns the numeric [result code] or [extended result code] for that
+** API call.
+** ^The sqlite3_extended_errcode()
+** interface is the same except that it always returns the
+** [extended result code] even when extended result codes are
+** disabled.
+**
+** The values returned by sqlite3_errcode() and/or
+** sqlite3_extended_errcode() might change with each API call.
+** Except, there are some interfaces that are guaranteed to never
+** change the value of the error code. The error-code preserving
+** interfaces are:
+**
+**
+**
sqlite3_errcode()
+**
sqlite3_extended_errcode()
+**
sqlite3_errmsg()
+**
sqlite3_errmsg16()
+**
+**
+** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
+** text that describes the error, as either UTF-8 or UTF-16 respectively.
+** ^(Memory to hold the error message string is managed internally.
+** The application does not need to worry about freeing the result.
+** However, the error string might be overwritten or deallocated by
+** subsequent calls to other SQLite interface functions.)^
+**
+** ^The sqlite3_errstr() interface returns the English-language text
+** that describes the [result code], as UTF-8.
+** ^(Memory to hold the error message string is managed internally
+** and must not be freed by the application)^.
+**
+** When the serialized [threading mode] is in use, it might be the
+** case that a second error occurs on a separate thread in between
+** the time of the first error and the call to these interfaces.
+** When that happens, the second error will be reported since these
+** interfaces always report the most recent result. To avoid
+** this, each thread can obtain exclusive use of the [database connection] D
+** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
+** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
+** all calls to the interfaces listed here are completed.
+**
+** If an interface fails with SQLITE_MISUSE, that means the interface
+** was invoked incorrectly by the application. In that case, the
+** error code and message may or may not be set.
+*/
+SQLITE_API int sqlite3_errcode(sqlite3 *db);
+SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
+SQLITE_API const char *sqlite3_errmsg(sqlite3*);
+SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
+SQLITE_API const char *sqlite3_errstr(int);
+
+/*
+** CAPI3REF: Prepared Statement Object
+** KEYWORDS: {prepared statement} {prepared statements}
+**
+** An instance of this object represents a single SQL statement that
+** has been compiled into binary form and is ready to be evaluated.
+**
+** Think of each SQL statement as a separate computer program. The
+** original SQL text is source code. A prepared statement object
+** is the compiled object code. All SQL must be converted into a
+** prepared statement before it can be run.
+**
+** The life-cycle of a prepared statement object usually goes like this:
+**
+**
+**
Create the prepared statement object using [sqlite3_prepare_v2()].
+**
Bind values to [parameters] using the sqlite3_bind_*()
+** interfaces.
+**
Run the SQL by calling [sqlite3_step()] one or more times.
+**
Reset the prepared statement using [sqlite3_reset()] then go back
+** to step 2. Do this zero or more times.
+**
Destroy the object using [sqlite3_finalize()].
+**
+*/
+typedef struct sqlite3_stmt sqlite3_stmt;
+
+/*
+** CAPI3REF: Run-time Limits
+** METHOD: sqlite3
+**
+** ^(This interface allows the size of various constructs to be limited
+** on a connection by connection basis. The first parameter is the
+** [database connection] whose limit is to be set or queried. The
+** second parameter is one of the [limit categories] that define a
+** class of constructs to be size limited. The third parameter is the
+** new limit for that construct.)^
+**
+** ^If the new limit is a negative number, the limit is unchanged.
+** ^(For each limit category SQLITE_LIMIT_NAME there is a
+** [limits | hard upper bound]
+** set at compile-time by a C preprocessor macro called
+** [limits | SQLITE_MAX_NAME].
+** (The "_LIMIT_" in the name is changed to "_MAX_".))^
+** ^Attempts to increase a limit above its hard upper bound are
+** silently truncated to the hard upper bound.
+**
+** ^Regardless of whether or not the limit was changed, the
+** [sqlite3_limit()] interface returns the prior value of the limit.
+** ^Hence, to find the current value of a limit without changing it,
+** simply invoke this interface with the third parameter set to -1.
+**
+** Run-time limits are intended for use in applications that manage
+** both their own internal database and also databases that are controlled
+** by untrusted external sources. An example application might be a
+** web browser that has its own databases for storing history and
+** separate databases controlled by JavaScript applications downloaded
+** off the Internet. The internal databases can be given the
+** large, default limits. Databases managed by external sources can
+** be given much smaller limits designed to prevent a denial of service
+** attack. Developers might also want to use the [sqlite3_set_authorizer()]
+** interface to further control untrusted SQL. The size of the database
+** created by an untrusted script can be contained using the
+** [max_page_count] [PRAGMA].
+**
+** New run-time limit categories may be added in future releases.
+*/
+SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
+
+/*
+** CAPI3REF: Run-Time Limit Categories
+** KEYWORDS: {limit category} {*limit categories}
+**
+** These constants define various performance limits
+** that can be lowered at run-time using [sqlite3_limit()].
+** The synopsis of the meanings of the various limits is shown below.
+** Additional information is available at [limits | Limits in SQLite].
+**
+**
+** [[SQLITE_LIMIT_LENGTH]] ^(
SQLITE_LIMIT_LENGTH
+**
The maximum size of any string or BLOB or table row, in bytes.
)^
+**
+** [[SQLITE_LIMIT_SQL_LENGTH]] ^(
SQLITE_LIMIT_SQL_LENGTH
+**
The maximum length of an SQL statement, in bytes.
)^
+**
+** [[SQLITE_LIMIT_COLUMN]] ^(
SQLITE_LIMIT_COLUMN
+**
The maximum number of columns in a table definition or in the
+** result set of a [SELECT] or the maximum number of columns in an index
+** or in an ORDER BY or GROUP BY clause.
)^
+**
+** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(
SQLITE_LIMIT_EXPR_DEPTH
+**
The maximum depth of the parse tree on any expression.
)^
+**
+** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(
SQLITE_LIMIT_COMPOUND_SELECT
+**
The maximum number of terms in a compound SELECT statement.
)^
+**
+** [[SQLITE_LIMIT_VDBE_OP]] ^(
SQLITE_LIMIT_VDBE_OP
+**
The maximum number of instructions in a virtual machine program
+** used to implement an SQL statement. If [sqlite3_prepare_v2()] or
+** the equivalent tries to allocate space for more than this many opcodes
+** in a single prepared statement, an SQLITE_NOMEM error is returned.
)^
+**
+** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(
SQLITE_LIMIT_FUNCTION_ARG
+**
The maximum number of arguments on a function.
)^
+**
+** [[SQLITE_LIMIT_ATTACHED]] ^(
SQLITE_LIMIT_ATTACHED
+**
The maximum number of [ATTACH | attached databases].)^
The maximum index number of any [parameter] in an SQL statement.)^
+**
+** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(
SQLITE_LIMIT_TRIGGER_DEPTH
+**
The maximum depth of recursion for triggers.
)^
+**
+** [[SQLITE_LIMIT_WORKER_THREADS]] ^(
SQLITE_LIMIT_WORKER_THREADS
+**
The maximum number of auxiliary worker threads that a single
+** [prepared statement] may start.
)^
+**
+*/
+#define SQLITE_LIMIT_LENGTH 0
+#define SQLITE_LIMIT_SQL_LENGTH 1
+#define SQLITE_LIMIT_COLUMN 2
+#define SQLITE_LIMIT_EXPR_DEPTH 3
+#define SQLITE_LIMIT_COMPOUND_SELECT 4
+#define SQLITE_LIMIT_VDBE_OP 5
+#define SQLITE_LIMIT_FUNCTION_ARG 6
+#define SQLITE_LIMIT_ATTACHED 7
+#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
+#define SQLITE_LIMIT_VARIABLE_NUMBER 9
+#define SQLITE_LIMIT_TRIGGER_DEPTH 10
+#define SQLITE_LIMIT_WORKER_THREADS 11
+
+/*
+** CAPI3REF: Prepare Flags
+**
+** These constants define various flags that can be passed into
+** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
+** [sqlite3_prepare16_v3()] interfaces.
+**
+** New flags may be added in future releases of SQLite.
+**
+**
+** [[SQLITE_PREPARE_PERSISTENT]] ^(
SQLITE_PREPARE_PERSISTENT
+**
The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
+** that the prepared statement will be retained for a long time and
+** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
+** and [sqlite3_prepare16_v3()] assume that the prepared statement will
+** be used just once or at most a few times and then destroyed using
+** [sqlite3_finalize()] relatively soon. The current implementation acts
+** on this hint by avoiding the use of [lookaside memory] so as not to
+** deplete the limited store of lookaside memory. Future versions of
+** SQLite may act on this hint differently.
+**
+*/
+#define SQLITE_PREPARE_PERSISTENT 0x01
+
+/*
+** CAPI3REF: Compiling An SQL Statement
+** KEYWORDS: {SQL statement compiler}
+** METHOD: sqlite3
+** CONSTRUCTOR: sqlite3_stmt
+**
+** To execute an SQL statement, it must first be compiled into a byte-code
+** program using one of these routines. Or, in other words, these routines
+** are constructors for the [prepared statement] object.
+**
+** The preferred routine to use is [sqlite3_prepare_v2()]. The
+** [sqlite3_prepare()] interface is legacy and should be avoided.
+** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
+** for special purposes.
+**
+** The use of the UTF-8 interfaces is preferred, as SQLite currently
+** does all parsing using UTF-8. The UTF-16 interfaces are provided
+** as a convenience. The UTF-16 interfaces work by converting the
+** input text into UTF-8, then invoking the corresponding UTF-8 interface.
+**
+** The first argument, "db", is a [database connection] obtained from a
+** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
+** [sqlite3_open16()]. The database connection must not have been closed.
+**
+** The second argument, "zSql", is the statement to be compiled, encoded
+** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(),
+** and sqlite3_prepare_v3()
+** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
+** and sqlite3_prepare16_v3() use UTF-16.
+**
+** ^If the nByte argument is negative, then zSql is read up to the
+** first zero terminator. ^If nByte is positive, then it is the
+** number of bytes read from zSql. ^If nByte is zero, then no prepared
+** statement is generated.
+** If the caller knows that the supplied string is nul-terminated, then
+** there is a small performance advantage to passing an nByte parameter that
+** is the number of bytes in the input string including
+** the nul-terminator.
+**
+** ^If pzTail is not NULL then *pzTail is made to point to the first byte
+** past the end of the first SQL statement in zSql. These routines only
+** compile the first statement in zSql, so *pzTail is left pointing to
+** what remains uncompiled.
+**
+** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
+** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
+** to NULL. ^If the input text contains no SQL (if the input is an empty
+** string or a comment) then *ppStmt is set to NULL.
+** The calling procedure is responsible for deleting the compiled
+** SQL statement using [sqlite3_finalize()] after it has finished with it.
+** ppStmt may not be NULL.
+**
+** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
+** otherwise an [error code] is returned.
+**
+** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
+** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
+** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
+** are retained for backwards compatibility, but their use is discouraged.
+** ^In the "vX" interfaces, the prepared statement
+** that is returned (the [sqlite3_stmt] object) contains a copy of the
+** original SQL text. This causes the [sqlite3_step()] interface to
+** behave differently in three ways:
+**
+**
+**
+** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
+** always used to do, [sqlite3_step()] will automatically recompile the SQL
+** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
+** retries will occur before sqlite3_step() gives up and returns an error.
+**
+**
+**
+** ^When an error occurs, [sqlite3_step()] will return one of the detailed
+** [error codes] or [extended error codes]. ^The legacy behavior was that
+** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
+** and the application would have to make a second call to [sqlite3_reset()]
+** in order to find the underlying cause of the problem. With the "v2" prepare
+** interfaces, the underlying reason for the error is returned immediately.
+**
+**
+**
+** ^If the specific value bound to [parameter | host parameter] in the
+** WHERE clause might influence the choice of query plan for a statement,
+** then the statement will be automatically recompiled, as if there had been
+** a schema change, on the first [sqlite3_step()] call following any change
+** to the [sqlite3_bind_text | bindings] of that [parameter].
+** ^The specific value of WHERE-clause [parameter] might influence the
+** choice of query plan if the parameter is the left-hand side of a [LIKE]
+** or [GLOB] operator or if the parameter is compared to an indexed column
+** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
+**
+**
+**
+**
^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
+** the extra prepFlags parameter, which is a bit array consisting of zero or
+** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The
+** sqlite3_prepare_v2() interface works exactly the same as
+** sqlite3_prepare_v3() with a zero prepFlags parameter.
+*/
+SQLITE_API int sqlite3_prepare(
+ sqlite3 *db, /* Database handle */
+ const char *zSql, /* SQL statement, UTF-8 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const char **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare_v2(
+ sqlite3 *db, /* Database handle */
+ const char *zSql, /* SQL statement, UTF-8 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const char **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare_v3(
+ sqlite3 *db, /* Database handle */
+ const char *zSql, /* SQL statement, UTF-8 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const char **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare16(
+ sqlite3 *db, /* Database handle */
+ const void *zSql, /* SQL statement, UTF-16 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const void **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare16_v2(
+ sqlite3 *db, /* Database handle */
+ const void *zSql, /* SQL statement, UTF-16 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const void **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare16_v3(
+ sqlite3 *db, /* Database handle */
+ const void *zSql, /* SQL statement, UTF-16 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const void **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+
+/*
+** CAPI3REF: Retrieving Statement SQL
+** METHOD: sqlite3_stmt
+**
+** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
+** SQL text used to create [prepared statement] P if P was
+** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
+** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
+** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
+** string containing the SQL text of prepared statement P with
+** [bound parameters] expanded.
+**
+** ^(For example, if a prepared statement is created using the SQL
+** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
+** and parameter :xyz is unbound, then sqlite3_sql() will return
+** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
+** will return "SELECT 2345,NULL".)^
+**
+** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
+** is available to hold the result, or if the result would exceed the
+** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
+**
+** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
+** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time
+** option causes sqlite3_expanded_sql() to always return NULL.
+**
+** ^The string returned by sqlite3_sql(P) is managed by SQLite and is
+** automatically freed when the prepared statement is finalized.
+** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
+** is obtained from [sqlite3_malloc()] and must be free by the application
+** by passing it to [sqlite3_free()].
+*/
+SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
+SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Determine If An SQL Statement Writes The Database
+** METHOD: sqlite3_stmt
+**
+** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
+** and only if the [prepared statement] X makes no direct changes to
+** the content of the database file.
+**
+** Note that [application-defined SQL functions] or
+** [virtual tables] might change the database indirectly as a side effect.
+** ^(For example, if an application defines a function "eval()" that
+** calls [sqlite3_exec()], then the following SQL statement would
+** change the database file through side-effects:
+**
+**
+** SELECT eval('DELETE FROM t1') FROM t2;
+**
+**
+** But because the [SELECT] statement does not change the database file
+** directly, sqlite3_stmt_readonly() would still return true.)^
+**
+** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
+** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
+** since the statements themselves do not actually modify the database but
+** rather they control the timing of when other statements modify the
+** database. ^The [ATTACH] and [DETACH] statements also cause
+** sqlite3_stmt_readonly() to return true since, while those statements
+** change the configuration of a database connection, they do not make
+** changes to the content of the database files on disk.
+** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
+** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
+** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
+** sqlite3_stmt_readonly() returns false for those commands.
+*/
+SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Determine If A Prepared Statement Has Been Reset
+** METHOD: sqlite3_stmt
+**
+** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
+** [prepared statement] S has been stepped at least once using
+** [sqlite3_step(S)] but has neither run to completion (returned
+** [SQLITE_DONE] from [sqlite3_step(S)]) nor
+** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
+** interface returns false if S is a NULL pointer. If S is not a
+** NULL pointer and is not a pointer to a valid [prepared statement]
+** object, then the behavior is undefined and probably undesirable.
+**
+** This interface can be used in combination [sqlite3_next_stmt()]
+** to locate all prepared statements associated with a database
+** connection that are in need of being reset. This can be used,
+** for example, in diagnostic routines to search for prepared
+** statements that are holding a transaction open.
+*/
+SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Dynamically Typed Value Object
+** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
+**
+** SQLite uses the sqlite3_value object to represent all values
+** that can be stored in a database table. SQLite uses dynamic typing
+** for the values it stores. ^Values stored in sqlite3_value objects
+** can be integers, floating point values, strings, BLOBs, or NULL.
+**
+** An sqlite3_value object may be either "protected" or "unprotected".
+** Some interfaces require a protected sqlite3_value. Other interfaces
+** will accept either a protected or an unprotected sqlite3_value.
+** Every interface that accepts sqlite3_value arguments specifies
+** whether or not it requires a protected sqlite3_value. The
+** [sqlite3_value_dup()] interface can be used to construct a new
+** protected sqlite3_value from an unprotected sqlite3_value.
+**
+** The terms "protected" and "unprotected" refer to whether or not
+** a mutex is held. An internal mutex is held for a protected
+** sqlite3_value object but no mutex is held for an unprotected
+** sqlite3_value object. If SQLite is compiled to be single-threaded
+** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
+** or if SQLite is run in one of reduced mutex modes
+** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
+** then there is no distinction between protected and unprotected
+** sqlite3_value objects and they can be used interchangeably. However,
+** for maximum code portability it is recommended that applications
+** still make the distinction between protected and unprotected
+** sqlite3_value objects even when not strictly required.
+**
+** ^The sqlite3_value objects that are passed as parameters into the
+** implementation of [application-defined SQL functions] are protected.
+** ^The sqlite3_value object returned by
+** [sqlite3_column_value()] is unprotected.
+** Unprotected sqlite3_value objects may only be used as arguments
+** to [sqlite3_result_value()], [sqlite3_bind_value()], and
+** [sqlite3_value_dup()].
+** The [sqlite3_value_blob | sqlite3_value_type()] family of
+** interfaces require protected sqlite3_value objects.
+*/
+typedef struct sqlite3_value sqlite3_value;
+
+/*
+** CAPI3REF: SQL Function Context Object
+**
+** The context in which an SQL function executes is stored in an
+** sqlite3_context object. ^A pointer to an sqlite3_context object
+** is always first parameter to [application-defined SQL functions].
+** The application-defined SQL function implementation will pass this
+** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
+** [sqlite3_aggregate_context()], [sqlite3_user_data()],
+** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
+** and/or [sqlite3_set_auxdata()].
+*/
+typedef struct sqlite3_context sqlite3_context;
+
+/*
+** CAPI3REF: Binding Values To Prepared Statements
+** KEYWORDS: {host parameter} {host parameters} {host parameter name}
+** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
+** METHOD: sqlite3_stmt
+**
+** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
+** literals may be replaced by a [parameter] that matches one of following
+** templates:
+**
+**
+**
?
+**
?NNN
+**
:VVV
+**
@VVV
+**
$VVV
+**
+**
+** In the templates above, NNN represents an integer literal,
+** and VVV represents an alphanumeric identifier.)^ ^The values of these
+** parameters (also called "host parameter names" or "SQL parameters")
+** can be set using the sqlite3_bind_*() routines defined here.
+**
+** ^The first argument to the sqlite3_bind_*() routines is always
+** a pointer to the [sqlite3_stmt] object returned from
+** [sqlite3_prepare_v2()] or its variants.
+**
+** ^The second argument is the index of the SQL parameter to be set.
+** ^The leftmost SQL parameter has an index of 1. ^When the same named
+** SQL parameter is used more than once, second and subsequent
+** occurrences have the same index as the first occurrence.
+** ^The index for named parameters can be looked up using the
+** [sqlite3_bind_parameter_index()] API if desired. ^The index
+** for "?NNN" parameters is the value of NNN.
+** ^The NNN value must be between 1 and the [sqlite3_limit()]
+** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
+**
+** ^The third argument is the value to bind to the parameter.
+** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
+** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
+** is ignored and the end result is the same as sqlite3_bind_null().
+**
+** ^(In those routines that have a fourth argument, its value is the
+** number of bytes in the parameter. To be clear: the value is the
+** number of bytes in the value, not the number of characters.)^
+** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
+** is negative, then the length of the string is
+** the number of bytes up to the first zero terminator.
+** If the fourth parameter to sqlite3_bind_blob() is negative, then
+** the behavior is undefined.
+** If a non-negative fourth parameter is provided to sqlite3_bind_text()
+** or sqlite3_bind_text16() or sqlite3_bind_text64() then
+** that parameter must be the byte offset
+** where the NUL terminator would occur assuming the string were NUL
+** terminated. If any NUL characters occur at byte offsets less than
+** the value of the fourth parameter then the resulting string value will
+** contain embedded NULs. The result of expressions involving strings
+** with embedded NULs is undefined.
+**
+** ^The fifth argument to the BLOB and string binding interfaces
+** is a destructor used to dispose of the BLOB or
+** string after SQLite has finished with it. ^The destructor is called
+** to dispose of the BLOB or string even if the call to bind API fails.
+** ^If the fifth argument is
+** the special value [SQLITE_STATIC], then SQLite assumes that the
+** information is in static, unmanaged space and does not need to be freed.
+** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
+** SQLite makes its own private copy of the data immediately, before
+** the sqlite3_bind_*() routine returns.
+**
+** ^The sixth argument to sqlite3_bind_text64() must be one of
+** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
+** to specify the encoding of the text in the third parameter. If
+** the sixth argument to sqlite3_bind_text64() is not one of the
+** allowed values shown above, or if the text encoding is different
+** from the encoding specified by the sixth parameter, then the behavior
+** is undefined.
+**
+** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
+** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
+** (just an integer to hold its size) while it is being processed.
+** Zeroblobs are intended to serve as placeholders for BLOBs whose
+** content is later written using
+** [sqlite3_blob_open | incremental BLOB I/O] routines.
+** ^A negative value for the zeroblob results in a zero-length BLOB.
+**
+** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
+** [prepared statement] S to have an SQL value of NULL, but to also be
+** associated with the pointer P of type T. ^D is either a NULL pointer or
+** a pointer to a destructor function for P. ^SQLite will invoke the
+** destructor D with a single argument of P when it is finished using
+** P. The T parameter should be a static string, preferably a string
+** literal. The sqlite3_bind_pointer() routine is part of the
+** [pointer passing interface] added for SQLite 3.20.0.
+**
+** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
+** for the [prepared statement] or with a prepared statement for which
+** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
+** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
+** routine is passed a [prepared statement] that has been finalized, the
+** result is undefined and probably harmful.
+**
+** ^Bindings are not cleared by the [sqlite3_reset()] routine.
+** ^Unbound parameters are interpreted as NULL.
+**
+** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
+** [error code] if anything goes wrong.
+** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
+** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
+** [SQLITE_MAX_LENGTH].
+** ^[SQLITE_RANGE] is returned if the parameter
+** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
+**
+** See also: [sqlite3_bind_parameter_count()],
+** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
+SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
+ void(*)(void*));
+SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
+SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
+SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
+SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
+SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
+SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
+SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
+ void(*)(void*), unsigned char encoding);
+SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
+SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
+SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
+SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
+
+/*
+** CAPI3REF: Number Of SQL Parameters
+** METHOD: sqlite3_stmt
+**
+** ^This routine can be used to find the number of [SQL parameters]
+** in a [prepared statement]. SQL parameters are tokens of the
+** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
+** placeholders for values that are [sqlite3_bind_blob | bound]
+** to the parameters at a later time.
+**
+** ^(This routine actually returns the index of the largest (rightmost)
+** parameter. For all forms except ?NNN, this will correspond to the
+** number of unique parameters. If parameters of the ?NNN form are used,
+** there may be gaps in the list.)^
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_name()], and
+** [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Name Of A Host Parameter
+** METHOD: sqlite3_stmt
+**
+** ^The sqlite3_bind_parameter_name(P,N) interface returns
+** the name of the N-th [SQL parameter] in the [prepared statement] P.
+** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
+** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
+** respectively.
+** In other words, the initial ":" or "$" or "@" or "?"
+** is included as part of the name.)^
+** ^Parameters of the form "?" without a following integer have no name
+** and are referred to as "nameless" or "anonymous parameters".
+**
+** ^The first host parameter has an index of 1, not 0.
+**
+** ^If the value N is out of range or if the N-th parameter is
+** nameless, then NULL is returned. ^The returned string is
+** always in UTF-8 encoding even if the named parameter was
+** originally specified as UTF-16 in [sqlite3_prepare16()],
+** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_count()], and
+** [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
+
+/*
+** CAPI3REF: Index Of A Parameter With A Given Name
+** METHOD: sqlite3_stmt
+**
+** ^Return the index of an SQL parameter given its name. ^The
+** index value returned is suitable for use as the second
+** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
+** is returned if no matching parameter is found. ^The parameter
+** name must be given in UTF-8 even if the original statement
+** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
+** [sqlite3_prepare16_v3()].
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_count()], and
+** [sqlite3_bind_parameter_name()].
+*/
+SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
+
+/*
+** CAPI3REF: Reset All Bindings On A Prepared Statement
+** METHOD: sqlite3_stmt
+**
+** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
+** the [sqlite3_bind_blob | bindings] on a [prepared statement].
+** ^Use this routine to reset all host parameters to NULL.
+*/
+SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Number Of Columns In A Result Set
+** METHOD: sqlite3_stmt
+**
+** ^Return the number of columns in the result set returned by the
+** [prepared statement]. ^If this routine returns 0, that means the
+** [prepared statement] returns no data (for example an [UPDATE]).
+** ^However, just because this routine returns a positive number does not
+** mean that one or more rows of data will be returned. ^A SELECT statement
+** will always have a positive sqlite3_column_count() but depending on the
+** WHERE clause constraints and the table content, it might return no rows.
+**
+** See also: [sqlite3_data_count()]
+*/
+SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Column Names In A Result Set
+** METHOD: sqlite3_stmt
+**
+** ^These routines return the name assigned to a particular column
+** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
+** interface returns a pointer to a zero-terminated UTF-8 string
+** and sqlite3_column_name16() returns a pointer to a zero-terminated
+** UTF-16 string. ^The first parameter is the [prepared statement]
+** that implements the [SELECT] statement. ^The second parameter is the
+** column number. ^The leftmost column is number 0.
+**
+** ^The returned string pointer is valid until either the [prepared statement]
+** is destroyed by [sqlite3_finalize()] or until the statement is automatically
+** reprepared by the first call to [sqlite3_step()] for a particular run
+** or until the next call to
+** sqlite3_column_name() or sqlite3_column_name16() on the same column.
+**
+** ^If sqlite3_malloc() fails during the processing of either routine
+** (for example during a conversion from UTF-8 to UTF-16) then a
+** NULL pointer is returned.
+**
+** ^The name of a result column is the value of the "AS" clause for
+** that column, if there is an AS clause. If there is no AS clause
+** then the name of the column is unspecified and may change from
+** one release of SQLite to the next.
+*/
+SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
+SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
+
+/*
+** CAPI3REF: Source Of Data In A Query Result
+** METHOD: sqlite3_stmt
+**
+** ^These routines provide a means to determine the database, table, and
+** table column that is the origin of a particular result column in
+** [SELECT] statement.
+** ^The name of the database or table or column can be returned as
+** either a UTF-8 or UTF-16 string. ^The _database_ routines return
+** the database name, the _table_ routines return the table name, and
+** the origin_ routines return the column name.
+** ^The returned string is valid until the [prepared statement] is destroyed
+** using [sqlite3_finalize()] or until the statement is automatically
+** reprepared by the first call to [sqlite3_step()] for a particular run
+** or until the same information is requested
+** again in a different encoding.
+**
+** ^The names returned are the original un-aliased names of the
+** database, table, and column.
+**
+** ^The first argument to these interfaces is a [prepared statement].
+** ^These functions return information about the Nth result column returned by
+** the statement, where N is the second function argument.
+** ^The left-most column is column 0 for these routines.
+**
+** ^If the Nth column returned by the statement is an expression or
+** subquery and is not a column value, then all of these functions return
+** NULL. ^These routine might also return NULL if a memory allocation error
+** occurs. ^Otherwise, they return the name of the attached database, table,
+** or column that query result column was extracted from.
+**
+** ^As with all other SQLite APIs, those whose names end with "16" return
+** UTF-16 encoded strings and the other functions return UTF-8.
+**
+** ^These APIs are only available if the library was compiled with the
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
+**
+** If two or more threads call one or more of these routines against the same
+** prepared statement and column at the same time then the results are
+** undefined.
+**
+** If two or more threads call one or more
+** [sqlite3_column_database_name | column metadata interfaces]
+** for the same [prepared statement] and result column
+** at the same time then the results are undefined.
+*/
+SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
+SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
+SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
+
+/*
+** CAPI3REF: Declared Datatype Of A Query Result
+** METHOD: sqlite3_stmt
+**
+** ^(The first parameter is a [prepared statement].
+** If this statement is a [SELECT] statement and the Nth column of the
+** returned result set of that [SELECT] is a table column (not an
+** expression or subquery) then the declared type of the table
+** column is returned.)^ ^If the Nth column of the result set is an
+** expression or subquery, then a NULL pointer is returned.
+** ^The returned string is always UTF-8 encoded.
+**
+** ^(For example, given the database schema:
+**
+** CREATE TABLE t1(c1 VARIANT);
+**
+** and the following statement to be compiled:
+**
+** SELECT c1 + 1, c1 FROM t1;
+**
+** this routine would return the string "VARIANT" for the second result
+** column (i==1), and a NULL pointer for the first result column (i==0).)^
+**
+** ^SQLite uses dynamic run-time typing. ^So just because a column
+** is declared to contain a particular type does not mean that the
+** data stored in that column is of the declared type. SQLite is
+** strongly typed, but the typing is dynamic not static. ^Type
+** is associated with individual values, not with the containers
+** used to hold those values.
+*/
+SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
+
+/*
+** CAPI3REF: Evaluate An SQL Statement
+** METHOD: sqlite3_stmt
+**
+** After a [prepared statement] has been prepared using any of
+** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
+** or [sqlite3_prepare16_v3()] or one of the legacy
+** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
+** must be called one or more times to evaluate the statement.
+**
+** The details of the behavior of the sqlite3_step() interface depend
+** on whether the statement was prepared using the newer "vX" interfaces
+** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
+** [sqlite3_prepare16_v2()] or the older legacy
+** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
+** new "vX" interface is recommended for new applications but the legacy
+** interface will continue to be supported.
+**
+** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
+** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
+** ^With the "v2" interface, any of the other [result codes] or
+** [extended result codes] might be returned as well.
+**
+** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
+** database locks it needs to do its job. ^If the statement is a [COMMIT]
+** or occurs outside of an explicit transaction, then you can retry the
+** statement. If the statement is not a [COMMIT] and occurs within an
+** explicit transaction then you should rollback the transaction before
+** continuing.
+**
+** ^[SQLITE_DONE] means that the statement has finished executing
+** successfully. sqlite3_step() should not be called again on this virtual
+** machine without first calling [sqlite3_reset()] to reset the virtual
+** machine back to its initial state.
+**
+** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
+** is returned each time a new row of data is ready for processing by the
+** caller. The values may be accessed using the [column access functions].
+** sqlite3_step() is called again to retrieve the next row of data.
+**
+** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
+** violation) has occurred. sqlite3_step() should not be called again on
+** the VM. More information may be found by calling [sqlite3_errmsg()].
+** ^With the legacy interface, a more specific error code (for example,
+** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
+** can be obtained by calling [sqlite3_reset()] on the
+** [prepared statement]. ^In the "v2" interface,
+** the more specific error code is returned directly by sqlite3_step().
+**
+** [SQLITE_MISUSE] means that the this routine was called inappropriately.
+** Perhaps it was called on a [prepared statement] that has
+** already been [sqlite3_finalize | finalized] or on one that had
+** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
+** be the case that the same database connection is being used by two or
+** more threads at the same moment in time.
+**
+** For all versions of SQLite up to and including 3.6.23.1, a call to
+** [sqlite3_reset()] was required after sqlite3_step() returned anything
+** other than [SQLITE_ROW] before any subsequent invocation of
+** sqlite3_step(). Failure to reset the prepared statement using
+** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
+** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1],
+** sqlite3_step() began
+** calling [sqlite3_reset()] automatically in this circumstance rather
+** than returning [SQLITE_MISUSE]. This is not considered a compatibility
+** break because any application that ever receives an SQLITE_MISUSE error
+** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
+** can be used to restore the legacy behavior.
+**
+** Goofy Interface Alert: In the legacy interface, the sqlite3_step()
+** API always returns a generic error code, [SQLITE_ERROR], following any
+** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
+** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
+** specific [error codes] that better describes the error.
+** We admit that this is a goofy design. The problem has been fixed
+** with the "v2" interface. If you prepare all of your SQL statements
+** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
+** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
+** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
+** then the more specific [error codes] are returned directly
+** by sqlite3_step(). The use of the "vX" interfaces is recommended.
+*/
+SQLITE_API int sqlite3_step(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Number of columns in a result set
+** METHOD: sqlite3_stmt
+**
+** ^The sqlite3_data_count(P) interface returns the number of columns in the
+** current row of the result set of [prepared statement] P.
+** ^If prepared statement P does not have results ready to return
+** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
+** interfaces) then sqlite3_data_count(P) returns 0.
+** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
+** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
+** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
+** will return non-zero if previous call to [sqlite3_step](P) returned
+** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
+** where it always returns zero since each step of that multi-step
+** pragma returns 0 columns of data.
+**
+** See also: [sqlite3_column_count()]
+*/
+SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Fundamental Datatypes
+** KEYWORDS: SQLITE_TEXT
+**
+** ^(Every value in SQLite has one of five fundamental datatypes:
+**
+**
+**
64-bit signed integer
+**
64-bit IEEE floating point number
+**
string
+**
BLOB
+**
NULL
+**
)^
+**
+** These constants are codes for each of those types.
+**
+** Note that the SQLITE_TEXT constant was also used in SQLite version 2
+** for a completely different meaning. Software that links against both
+** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
+** SQLITE_TEXT.
+*/
+#define SQLITE_INTEGER 1
+#define SQLITE_FLOAT 2
+#define SQLITE_BLOB 4
+#define SQLITE_NULL 5
+#ifdef SQLITE_TEXT
+# undef SQLITE_TEXT
+#else
+# define SQLITE_TEXT 3
+#endif
+#define SQLITE3_TEXT 3
+
+/*
+** CAPI3REF: Result Values From A Query
+** KEYWORDS: {column access functions}
+** METHOD: sqlite3_stmt
+**
+** Summary:
+**
+**
sqlite3_column_blob
→
BLOB result
+**
sqlite3_column_double
→
REAL result
+**
sqlite3_column_int
→
32-bit INTEGER result
+**
sqlite3_column_int64
→
64-bit INTEGER result
+**
sqlite3_column_text
→
UTF-8 TEXT result
+**
sqlite3_column_text16
→
UTF-16 TEXT result
+**
sqlite3_column_value
→
The result as an
+** [sqlite3_value|unprotected sqlite3_value] object.
+**
+**
sqlite3_column_bytes
→
Size of a BLOB
+** or a UTF-8 TEXT result in bytes
+**
sqlite3_column_bytes16
+**
→
Size of UTF-16
+** TEXT in bytes
+**
sqlite3_column_type
→
Default
+** datatype of the result
+**
+**
+** Details:
+**
+** ^These routines return information about a single column of the current
+** result row of a query. ^In every case the first argument is a pointer
+** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
+** that was returned from [sqlite3_prepare_v2()] or one of its variants)
+** and the second argument is the index of the column for which information
+** should be returned. ^The leftmost column of the result set has the index 0.
+** ^The number of columns in the result can be determined using
+** [sqlite3_column_count()].
+**
+** If the SQL statement does not currently point to a valid row, or if the
+** column index is out of range, the result is undefined.
+** These routines may only be called when the most recent call to
+** [sqlite3_step()] has returned [SQLITE_ROW] and neither
+** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
+** If any of these routines are called after [sqlite3_reset()] or
+** [sqlite3_finalize()] or after [sqlite3_step()] has returned
+** something other than [SQLITE_ROW], the results are undefined.
+** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
+** are called from a different thread while any of these routines
+** are pending, then the results are undefined.
+**
+** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
+** each return the value of a result column in a specific data format. If
+** the result column is not initially in the requested format (for example,
+** if the query returns an integer but the sqlite3_column_text() interface
+** is used to extract the value) then an automatic type conversion is performed.
+**
+** ^The sqlite3_column_type() routine returns the
+** [SQLITE_INTEGER | datatype code] for the initial data type
+** of the result column. ^The returned value is one of [SQLITE_INTEGER],
+** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
+** The return value of sqlite3_column_type() can be used to decide which
+** of the first six interface should be used to extract the column value.
+** The value returned by sqlite3_column_type() is only meaningful if no
+** automatic type conversions have occurred for the value in question.
+** After a type conversion, the result of calling sqlite3_column_type()
+** is undefined, though harmless. Future
+** versions of SQLite may change the behavior of sqlite3_column_type()
+** following a type conversion.
+**
+** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
+** or sqlite3_column_bytes16() interfaces can be used to determine the size
+** of that BLOB or string.
+**
+** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
+** the string to UTF-8 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
+**
+** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
+** the string to UTF-16 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes16() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
+**
+** ^The values returned by [sqlite3_column_bytes()] and
+** [sqlite3_column_bytes16()] do not include the zero terminators at the end
+** of the string. ^For clarity: the values returned by
+** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
+** bytes in the string, not the number of characters.
+**
+** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
+** even empty strings, are always zero-terminated. ^The return
+** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
+**
+** Warning: ^The object returned by [sqlite3_column_value()] is an
+** [unprotected sqlite3_value] object. In a multithreaded environment,
+** an unprotected sqlite3_value object may only be used safely with
+** [sqlite3_bind_value()] and [sqlite3_result_value()].
+** If the [unprotected sqlite3_value] object returned by
+** [sqlite3_column_value()] is used in any other way, including calls
+** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
+** or [sqlite3_value_bytes()], the behavior is not threadsafe.
+** Hence, the sqlite3_column_value() interface
+** is normally only useful within the implementation of
+** [application-defined SQL functions] or [virtual tables], not within
+** top-level application code.
+**
+** The these routines may attempt to convert the datatype of the result.
+** ^For example, if the internal representation is FLOAT and a text result
+** is requested, [sqlite3_snprintf()] is used internally to perform the
+** conversion automatically. ^(The following table details the conversions
+** that are applied:
+**
+**
+**
+**
Internal Type
Requested Type
Conversion
+**
+**
NULL
INTEGER
Result is 0
+**
NULL
FLOAT
Result is 0.0
+**
NULL
TEXT
Result is a NULL pointer
+**
NULL
BLOB
Result is a NULL pointer
+**
INTEGER
FLOAT
Convert from integer to float
+**
INTEGER
TEXT
ASCII rendering of the integer
+**
INTEGER
BLOB
Same as INTEGER->TEXT
+**
FLOAT
INTEGER
[CAST] to INTEGER
+**
FLOAT
TEXT
ASCII rendering of the float
+**
FLOAT
BLOB
[CAST] to BLOB
+**
TEXT
INTEGER
[CAST] to INTEGER
+**
TEXT
FLOAT
[CAST] to REAL
+**
TEXT
BLOB
No change
+**
BLOB
INTEGER
[CAST] to INTEGER
+**
BLOB
FLOAT
[CAST] to REAL
+**
BLOB
TEXT
Add a zero terminator if needed
+**
+**
)^
+**
+** Note that when type conversions occur, pointers returned by prior
+** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
+** sqlite3_column_text16() may be invalidated.
+** Type conversions and pointer invalidations might occur
+** in the following cases:
+**
+**
+**
The initial content is a BLOB and sqlite3_column_text() or
+** sqlite3_column_text16() is called. A zero-terminator might
+** need to be added to the string.
+**
The initial content is UTF-8 text and sqlite3_column_bytes16() or
+** sqlite3_column_text16() is called. The content must be converted
+** to UTF-16.
+**
The initial content is UTF-16 text and sqlite3_column_bytes() or
+** sqlite3_column_text() is called. The content must be converted
+** to UTF-8.
+**
+**
+** ^Conversions between UTF-16be and UTF-16le are always done in place and do
+** not invalidate a prior pointer, though of course the content of the buffer
+** that the prior pointer references will have been modified. Other kinds
+** of conversion are done in place when it is possible, but sometimes they
+** are not possible and in those cases prior pointers are invalidated.
+**
+** The safest policy is to invoke these routines
+** in one of the following ways:
+**
+**
+**
sqlite3_column_text() followed by sqlite3_column_bytes()
+**
sqlite3_column_blob() followed by sqlite3_column_bytes()
+**
sqlite3_column_text16() followed by sqlite3_column_bytes16()
+**
+**
+** In other words, you should call sqlite3_column_text(),
+** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
+** into the desired format, then invoke sqlite3_column_bytes() or
+** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
+** to sqlite3_column_text() or sqlite3_column_blob() with calls to
+** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
+** with calls to sqlite3_column_bytes().
+**
+** ^The pointers returned are valid until a type conversion occurs as
+** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
+** [sqlite3_finalize()] is called. ^The memory space used to hold strings
+** and BLOBs is freed automatically. Do not pass the pointers returned
+** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
+** [sqlite3_free()].
+**
+** As long as the input parameters are correct, these routines will only
+** fail if an out-of-memory error occurs during a format conversion.
+** Only the following subset of interfaces are subject to out-of-memory
+** errors:
+**
+**
+**
sqlite3_column_blob()
+**
sqlite3_column_text()
+**
sqlite3_column_text16()
+**
sqlite3_column_bytes()
+**
sqlite3_column_bytes16()
+**
+**
+** If an out-of-memory error occurs, then the return value from these
+** routines is the same as if the column had contained an SQL NULL value.
+** Valid SQL NULL returns can be distinguished from out-of-memory errors
+** by invoking the [sqlite3_errcode()] immediately after the suspect
+** return value is obtained and before any
+** other SQLite interface is called on the same [database connection].
+*/
+SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
+SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
+SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
+SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
+SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
+SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
+
+/*
+** CAPI3REF: Destroy A Prepared Statement Object
+** DESTRUCTOR: sqlite3_stmt
+**
+** ^The sqlite3_finalize() function is called to delete a [prepared statement].
+** ^If the most recent evaluation of the statement encountered no errors
+** or if the statement is never been evaluated, then sqlite3_finalize() returns
+** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
+** sqlite3_finalize(S) returns the appropriate [error code] or
+** [extended error code].
+**
+** ^The sqlite3_finalize(S) routine can be called at any point during
+** the life cycle of [prepared statement] S:
+** before statement S is ever evaluated, after
+** one or more calls to [sqlite3_reset()], or after any call
+** to [sqlite3_step()] regardless of whether or not the statement has
+** completed execution.
+**
+** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
+**
+** The application must finalize every [prepared statement] in order to avoid
+** resource leaks. It is a grievous error for the application to try to use
+** a prepared statement after it has been finalized. Any use of a prepared
+** statement after it has been finalized can result in undefined and
+** undesirable behavior such as segfaults and heap corruption.
+*/
+SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Reset A Prepared Statement Object
+** METHOD: sqlite3_stmt
+**
+** The sqlite3_reset() function is called to reset a [prepared statement]
+** object back to its initial state, ready to be re-executed.
+** ^Any SQL statement variables that had values bound to them using
+** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
+** Use [sqlite3_clear_bindings()] to reset the bindings.
+**
+** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
+** back to the beginning of its program.
+**
+** ^If the most recent call to [sqlite3_step(S)] for the
+** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
+** or if [sqlite3_step(S)] has never before been called on S,
+** then [sqlite3_reset(S)] returns [SQLITE_OK].
+**
+** ^If the most recent call to [sqlite3_step(S)] for the
+** [prepared statement] S indicated an error, then
+** [sqlite3_reset(S)] returns an appropriate [error code].
+**
+** ^The [sqlite3_reset(S)] interface does not change the values
+** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
+*/
+SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Create Or Redefine SQL Functions
+** KEYWORDS: {function creation routines}
+** KEYWORDS: {application-defined SQL function}
+** KEYWORDS: {application-defined SQL functions}
+** METHOD: sqlite3
+**
+** ^These functions (collectively known as "function creation routines")
+** are used to add SQL functions or aggregates or to redefine the behavior
+** of existing SQL functions or aggregates. The only differences between
+** the three "sqlite3_create_function*" routines are the text encoding
+** expected for the second parameter (the name of the function being
+** created) and the presence or absence of a destructor callback for
+** the application data pointer. Function sqlite3_create_window_function()
+** is similar, but allows the user to supply the extra callback functions
+** needed by [aggregate window functions].
+**
+** ^The first parameter is the [database connection] to which the SQL
+** function is to be added. ^If an application uses more than one database
+** connection then application-defined SQL functions must be added
+** to each database connection separately.
+**
+** ^The second parameter is the name of the SQL function to be created or
+** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
+** representation, exclusive of the zero-terminator. ^Note that the name
+** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
+** ^Any attempt to create a function with a longer name
+** will result in [SQLITE_MISUSE] being returned.
+**
+** ^The third parameter (nArg)
+** is the number of arguments that the SQL function or
+** aggregate takes. ^If this parameter is -1, then the SQL function or
+** aggregate may take any number of arguments between 0 and the limit
+** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
+** parameter is less than -1 or greater than 127 then the behavior is
+** undefined.
+**
+** ^The fourth parameter, eTextRep, specifies what
+** [SQLITE_UTF8 | text encoding] this SQL function prefers for
+** its parameters. The application should set this parameter to
+** [SQLITE_UTF16LE] if the function implementation invokes
+** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
+** implementation invokes [sqlite3_value_text16be()] on an input, or
+** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
+** otherwise. ^The same SQL function may be registered multiple times using
+** different preferred text encodings, with different implementations for
+** each encoding.
+** ^When multiple implementations of the same function are available, SQLite
+** will pick the one that involves the least amount of data conversion.
+**
+** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
+** to signal that the function will always return the same result given
+** the same inputs within a single SQL statement. Most SQL functions are
+** deterministic. The built-in [random()] SQL function is an example of a
+** function that is not deterministic. The SQLite query planner is able to
+** perform additional optimizations on deterministic functions, so use
+** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
+**
+** ^(The fifth parameter is an arbitrary pointer. The implementation of the
+** function can gain access to this pointer using [sqlite3_user_data()].)^
+**
+** ^The sixth, seventh and eighth parameters passed to the three
+** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are
+** pointers to C-language functions that implement the SQL function or
+** aggregate. ^A scalar SQL function requires an implementation of the xFunc
+** callback only; NULL pointers must be passed as the xStep and xFinal
+** parameters. ^An aggregate SQL function requires an implementation of xStep
+** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
+** SQL function or aggregate, pass NULL pointers for all three function
+** callbacks.
+**
+** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue
+** and xInverse) passed to sqlite3_create_window_function are pointers to
+** C-language callbacks that implement the new function. xStep and xFinal
+** must both be non-NULL. xValue and xInverse may either both be NULL, in
+** which case a regular aggregate function is created, or must both be
+** non-NULL, in which case the new function may be used as either an aggregate
+** or aggregate window function. More details regarding the implementation
+** of aggregate window functions are
+** [user-defined window functions|available here].
+**
+** ^(If the final parameter to sqlite3_create_function_v2() or
+** sqlite3_create_window_function() is not NULL, then it is destructor for
+** the application data pointer. The destructor is invoked when the function
+** is deleted, either by being overloaded or when the database connection
+** closes.)^ ^The destructor is also invoked if the call to
+** sqlite3_create_function_v2() fails. ^When the destructor callback is
+** invoked, it is passed a single argument which is a copy of the application
+** data pointer which was the fifth parameter to sqlite3_create_function_v2().
+**
+** ^It is permitted to register multiple implementations of the same
+** functions with the same name but with either differing numbers of
+** arguments or differing preferred text encodings. ^SQLite will use
+** the implementation that most closely matches the way in which the
+** SQL function is used. ^A function implementation with a non-negative
+** nArg parameter is a better match than a function implementation with
+** a negative nArg. ^A function where the preferred text encoding
+** matches the database encoding is a better
+** match than a function where the encoding is different.
+** ^A function where the encoding difference is between UTF16le and UTF16be
+** is a closer match than a function where the encoding difference is
+** between UTF8 and UTF16.
+**
+** ^Built-in functions may be overloaded by new application-defined functions.
+**
+** ^An application-defined function is permitted to call other
+** SQLite interfaces. However, such calls must not
+** close the database connection nor finalize or reset the prepared
+** statement in which the function is running.
+*/
+SQLITE_API int sqlite3_create_function(
+ sqlite3 *db,
+ const char *zFunctionName,
+ int nArg,
+ int eTextRep,
+ void *pApp,
+ void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+ void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+ void (*xFinal)(sqlite3_context*)
+);
+SQLITE_API int sqlite3_create_function16(
+ sqlite3 *db,
+ const void *zFunctionName,
+ int nArg,
+ int eTextRep,
+ void *pApp,
+ void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+ void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+ void (*xFinal)(sqlite3_context*)
+);
+SQLITE_API int sqlite3_create_function_v2(
+ sqlite3 *db,
+ const char *zFunctionName,
+ int nArg,
+ int eTextRep,
+ void *pApp,
+ void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+ void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+ void (*xFinal)(sqlite3_context*),
+ void(*xDestroy)(void*)
+);
+SQLITE_API int sqlite3_create_window_function(
+ sqlite3 *db,
+ const char *zFunctionName,
+ int nArg,
+ int eTextRep,
+ void *pApp,
+ void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+ void (*xFinal)(sqlite3_context*),
+ void (*xValue)(sqlite3_context*),
+ void (*xInverse)(sqlite3_context*,int,sqlite3_value**),
+ void(*xDestroy)(void*)
+);
+
+/*
+** CAPI3REF: Text Encodings
+**
+** These constant define integer codes that represent the various
+** text encodings supported by SQLite.
+*/
+#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */
+#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */
+#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */
+#define SQLITE_UTF16 4 /* Use native byte order */
+#define SQLITE_ANY 5 /* Deprecated */
+#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
+
+/*
+** CAPI3REF: Function Flags
+**
+** These constants may be ORed together with the
+** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
+** to [sqlite3_create_function()], [sqlite3_create_function16()], or
+** [sqlite3_create_function_v2()].
+*/
+#define SQLITE_DETERMINISTIC 0x800
+
+/*
+** CAPI3REF: Deprecated Functions
+** DEPRECATED
+**
+** These functions are [deprecated]. In order to maintain
+** backwards compatibility with older code, these functions continue
+** to be supported. However, new applications should avoid
+** the use of these functions. To encourage programmers to avoid
+** these functions, we will not explain what they do.
+*/
+#ifndef SQLITE_OMIT_DEPRECATED
+SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
+SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
+ void*,sqlite3_int64);
+#endif
+
+/*
+** CAPI3REF: Obtaining SQL Values
+** METHOD: sqlite3_value
+**
+** Summary:
+**
+**
sqlite3_value_blob
→
BLOB value
+**
sqlite3_value_double
→
REAL value
+**
sqlite3_value_int
→
32-bit INTEGER value
+**
sqlite3_value_int64
→
64-bit INTEGER value
+**
sqlite3_value_pointer
→
Pointer value
+**
sqlite3_value_text
→
UTF-8 TEXT value
+**
sqlite3_value_text16
→
UTF-16 TEXT value in
+** the native byteorder
+**
sqlite3_value_text16be
→
UTF-16be TEXT value
+**
sqlite3_value_text16le
→
UTF-16le TEXT value
+**
+**
sqlite3_value_bytes
→
Size of a BLOB
+** or a UTF-8 TEXT in bytes
+**
sqlite3_value_bytes16
+**
→
Size of UTF-16
+** TEXT in bytes
+**
sqlite3_value_type
→
Default
+** datatype of the value
+**
sqlite3_value_numeric_type
+**
→
Best numeric datatype of the value
+**
sqlite3_value_nochange
+**
→
True if the column is unchanged in an UPDATE
+** against a virtual table.
+**
+**
+** Details:
+**
+** These routines extract type, size, and content information from
+** [protected sqlite3_value] objects. Protected sqlite3_value objects
+** are used to pass parameter information into implementation of
+** [application-defined SQL functions] and [virtual tables].
+**
+** These routines work only with [protected sqlite3_value] objects.
+** Any attempt to use these routines on an [unprotected sqlite3_value]
+** is not threadsafe.
+**
+** ^These routines work just like the corresponding [column access functions]
+** except that these routines take a single [protected sqlite3_value] object
+** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
+**
+** ^The sqlite3_value_text16() interface extracts a UTF-16 string
+** in the native byte-order of the host machine. ^The
+** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
+** extract UTF-16 strings as big-endian and little-endian respectively.
+**
+** ^If [sqlite3_value] object V was initialized
+** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
+** and if X and Y are strings that compare equal according to strcmp(X,Y),
+** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise,
+** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
+** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
+**
+** ^(The sqlite3_value_type(V) interface returns the
+** [SQLITE_INTEGER | datatype code] for the initial datatype of the
+** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
+** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
+** Other interfaces might change the datatype for an sqlite3_value object.
+** For example, if the datatype is initially SQLITE_INTEGER and
+** sqlite3_value_text(V) is called to extract a text value for that
+** integer, then subsequent calls to sqlite3_value_type(V) might return
+** SQLITE_TEXT. Whether or not a persistent internal datatype conversion
+** occurs is undefined and may change from one release of SQLite to the next.
+**
+** ^(The sqlite3_value_numeric_type() interface attempts to apply
+** numeric affinity to the value. This means that an attempt is
+** made to convert the value to an integer or floating point. If
+** such a conversion is possible without loss of information (in other
+** words, if the value is a string that looks like a number)
+** then the conversion is performed. Otherwise no conversion occurs.
+** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
+**
+** ^Within the [xUpdate] method of a [virtual table], the
+** sqlite3_value_nochange(X) interface returns true if and only if
+** the column corresponding to X is unchanged by the UPDATE operation
+** that the xUpdate method call was invoked to implement and if
+** and the prior [xColumn] method call that was invoked to extracted
+** the value for that column returned without setting a result (probably
+** because it queried [sqlite3_vtab_nochange()] and found that the column
+** was unchanging). ^Within an [xUpdate] method, any value for which
+** sqlite3_value_nochange(X) is true will in all other respects appear
+** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other
+** than within an [xUpdate] method call for an UPDATE statement, then
+** the return value is arbitrary and meaningless.
+**
+** Please pay particular attention to the fact that the pointer returned
+** from [sqlite3_value_blob()], [sqlite3_value_text()], or
+** [sqlite3_value_text16()] can be invalidated by a subsequent call to
+** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
+** or [sqlite3_value_text16()].
+**
+** These routines must be called from the same thread as
+** the SQL function that supplied the [sqlite3_value*] parameters.
+**
+** As long as the input parameter is correct, these routines can only
+** fail if an out-of-memory error occurs during a format conversion.
+** Only the following subset of interfaces are subject to out-of-memory
+** errors:
+**
+**
+**
sqlite3_value_blob()
+**
sqlite3_value_text()
+**
sqlite3_value_text16()
+**
sqlite3_value_text16le()
+**
sqlite3_value_text16be()
+**
sqlite3_value_bytes()
+**
sqlite3_value_bytes16()
+**
+**
+** If an out-of-memory error occurs, then the return value from these
+** routines is the same as if the column had contained an SQL NULL value.
+** Valid SQL NULL returns can be distinguished from out-of-memory errors
+** by invoking the [sqlite3_errcode()] immediately after the suspect
+** return value is obtained and before any
+** other SQLite interface is called on the same [database connection].
+*/
+SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
+SQLITE_API double sqlite3_value_double(sqlite3_value*);
+SQLITE_API int sqlite3_value_int(sqlite3_value*);
+SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
+SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
+SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
+SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
+SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
+SQLITE_API int sqlite3_value_type(sqlite3_value*);
+SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
+SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
+
+/*
+** CAPI3REF: Finding The Subtype Of SQL Values
+** METHOD: sqlite3_value
+**
+** The sqlite3_value_subtype(V) function returns the subtype for
+** an [application-defined SQL function] argument V. The subtype
+** information can be used to pass a limited amount of context from
+** one SQL function to another. Use the [sqlite3_result_subtype()]
+** routine to set the subtype for the return value of an SQL function.
+*/
+SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
+
+/*
+** CAPI3REF: Copy And Free SQL Values
+** METHOD: sqlite3_value
+**
+** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
+** object D and returns a pointer to that copy. ^The [sqlite3_value] returned
+** is a [protected sqlite3_value] object even if the input is not.
+** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
+** memory allocation fails.
+**
+** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
+** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer
+** then sqlite3_value_free(V) is a harmless no-op.
+*/
+SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
+SQLITE_API void sqlite3_value_free(sqlite3_value*);
+
+/*
+** CAPI3REF: Obtain Aggregate Function Context
+** METHOD: sqlite3_context
+**
+** Implementations of aggregate SQL functions use this
+** routine to allocate memory for storing their state.
+**
+** ^The first time the sqlite3_aggregate_context(C,N) routine is called
+** for a particular aggregate function, SQLite
+** allocates N of memory, zeroes out that memory, and returns a pointer
+** to the new memory. ^On second and subsequent calls to
+** sqlite3_aggregate_context() for the same aggregate function instance,
+** the same buffer is returned. Sqlite3_aggregate_context() is normally
+** called once for each invocation of the xStep callback and then one
+** last time when the xFinal callback is invoked. ^(When no rows match
+** an aggregate query, the xStep() callback of the aggregate function
+** implementation is never called and xFinal() is called exactly once.
+** In those cases, sqlite3_aggregate_context() might be called for the
+** first time from within xFinal().)^
+**
+** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
+** when first called if N is less than or equal to zero or if a memory
+** allocate error occurs.
+**
+** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
+** determined by the N parameter on first successful call. Changing the
+** value of N in subsequent call to sqlite3_aggregate_context() within
+** the same aggregate function instance will not resize the memory
+** allocation.)^ Within the xFinal callback, it is customary to set
+** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
+** pointless memory allocations occur.
+**
+** ^SQLite automatically frees the memory allocated by
+** sqlite3_aggregate_context() when the aggregate query concludes.
+**
+** The first parameter must be a copy of the
+** [sqlite3_context | SQL function context] that is the first parameter
+** to the xStep or xFinal callback routine that implements the aggregate
+** function.
+**
+** This routine must be called from the same thread in which
+** the aggregate SQL function is running.
+*/
+SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
+
+/*
+** CAPI3REF: User Data For Functions
+** METHOD: sqlite3_context
+**
+** ^The sqlite3_user_data() interface returns a copy of
+** the pointer that was the pUserData parameter (the 5th parameter)
+** of the [sqlite3_create_function()]
+** and [sqlite3_create_function16()] routines that originally
+** registered the application defined function.
+**
+** This routine must be called from the same thread in which
+** the application-defined function is running.
+*/
+SQLITE_API void *sqlite3_user_data(sqlite3_context*);
+
+/*
+** CAPI3REF: Database Connection For Functions
+** METHOD: sqlite3_context
+**
+** ^The sqlite3_context_db_handle() interface returns a copy of
+** the pointer to the [database connection] (the 1st parameter)
+** of the [sqlite3_create_function()]
+** and [sqlite3_create_function16()] routines that originally
+** registered the application defined function.
+*/
+SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
+
+/*
+** CAPI3REF: Function Auxiliary Data
+** METHOD: sqlite3_context
+**
+** These functions may be used by (non-aggregate) SQL functions to
+** associate metadata with argument values. If the same value is passed to
+** multiple invocations of the same SQL function during query execution, under
+** some circumstances the associated metadata may be preserved. An example
+** of where this might be useful is in a regular-expression matching
+** function. The compiled version of the regular expression can be stored as
+** metadata associated with the pattern string.
+** Then as long as the pattern string remains the same,
+** the compiled regular expression can be reused on multiple
+** invocations of the same function.
+**
+** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata
+** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
+** value to the application-defined function. ^N is zero for the left-most
+** function argument. ^If there is no metadata
+** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
+** returns a NULL pointer.
+**
+** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
+** argument of the application-defined function. ^Subsequent
+** calls to sqlite3_get_auxdata(C,N) return P from the most recent
+** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
+** NULL if the metadata has been discarded.
+** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
+** SQLite will invoke the destructor function X with parameter P exactly
+** once, when the metadata is discarded.
+** SQLite is free to discard the metadata at any time, including:
+**
^(when the corresponding function parameter changes)^, or
+**
^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
+** SQL statement)^, or
+**
^(when sqlite3_set_auxdata() is invoked again on the same
+** parameter)^, or
+**
^(during the original sqlite3_set_auxdata() call when a memory
+** allocation error occurs.)^
+**
+** Note the last bullet in particular. The destructor X in
+** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
+** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
+** should be called near the end of the function implementation and the
+** function implementation should not make any use of P after
+** sqlite3_set_auxdata() has been called.
+**
+** ^(In practice, metadata is preserved between function calls for
+** function parameters that are compile-time constants, including literal
+** values and [parameters] and expressions composed from the same.)^
+**
+** The value of the N parameter to these interfaces should be non-negative.
+** Future enhancements may make use of negative N values to define new
+** kinds of function caching behavior.
+**
+** These routines must be called from the same thread in which
+** the SQL function is running.
+*/
+SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
+SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
+
+
+/*
+** CAPI3REF: Constants Defining Special Destructor Behavior
+**
+** These are special values for the destructor that is passed in as the
+** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
+** argument is SQLITE_STATIC, it means that the content pointer is constant
+** and will never change. It does not need to be destroyed. ^The
+** SQLITE_TRANSIENT value means that the content will likely change in
+** the near future and that SQLite should make its own private copy of
+** the content before returning.
+**
+** The typedef is necessary to work around problems in certain
+** C++ compilers.
+*/
+typedef void (*sqlite3_destructor_type)(void*);
+#define SQLITE_STATIC ((sqlite3_destructor_type)0)
+#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
+
+/*
+** CAPI3REF: Setting The Result Of An SQL Function
+** METHOD: sqlite3_context
+**
+** These routines are used by the xFunc or xFinal callbacks that
+** implement SQL functions and aggregates. See
+** [sqlite3_create_function()] and [sqlite3_create_function16()]
+** for additional information.
+**
+** These functions work very much like the [parameter binding] family of
+** functions used to bind values to host parameters in prepared statements.
+** Refer to the [SQL parameter] documentation for additional information.
+**
+** ^The sqlite3_result_blob() interface sets the result from
+** an application-defined function to be the BLOB whose content is pointed
+** to by the second parameter and which is N bytes long where N is the
+** third parameter.
+**
+** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
+** interfaces set the result of the application-defined function to be
+** a BLOB containing all zero bytes and N bytes in size.
+**
+** ^The sqlite3_result_double() interface sets the result from
+** an application-defined function to be a floating point value specified
+** by its 2nd argument.
+**
+** ^The sqlite3_result_error() and sqlite3_result_error16() functions
+** cause the implemented SQL function to throw an exception.
+** ^SQLite uses the string pointed to by the
+** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
+** as the text of an error message. ^SQLite interprets the error
+** message string from sqlite3_result_error() as UTF-8. ^SQLite
+** interprets the string from sqlite3_result_error16() as UTF-16 in native
+** byte order. ^If the third parameter to sqlite3_result_error()
+** or sqlite3_result_error16() is negative then SQLite takes as the error
+** message all text up through the first zero character.
+** ^If the third parameter to sqlite3_result_error() or
+** sqlite3_result_error16() is non-negative then SQLite takes that many
+** bytes (not characters) from the 2nd parameter as the error message.
+** ^The sqlite3_result_error() and sqlite3_result_error16()
+** routines make a private copy of the error message text before
+** they return. Hence, the calling function can deallocate or
+** modify the text after they return without harm.
+** ^The sqlite3_result_error_code() function changes the error code
+** returned by SQLite as a result of an error in a function. ^By default,
+** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
+** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
+**
+** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
+** error indicating that a string or BLOB is too long to represent.
+**
+** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
+** error indicating that a memory allocation failed.
+**
+** ^The sqlite3_result_int() interface sets the return value
+** of the application-defined function to be the 32-bit signed integer
+** value given in the 2nd argument.
+** ^The sqlite3_result_int64() interface sets the return value
+** of the application-defined function to be the 64-bit signed integer
+** value given in the 2nd argument.
+**
+** ^The sqlite3_result_null() interface sets the return value
+** of the application-defined function to be NULL.
+**
+** ^The sqlite3_result_text(), sqlite3_result_text16(),
+** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
+** set the return value of the application-defined function to be
+** a text string which is represented as UTF-8, UTF-16 native byte order,
+** UTF-16 little endian, or UTF-16 big endian, respectively.
+** ^The sqlite3_result_text64() interface sets the return value of an
+** application-defined function to be a text string in an encoding
+** specified by the fifth (and last) parameter, which must be one
+** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
+** ^SQLite takes the text result from the application from
+** the 2nd parameter of the sqlite3_result_text* interfaces.
+** ^If the 3rd parameter to the sqlite3_result_text* interfaces
+** is negative, then SQLite takes result text from the 2nd parameter
+** through the first zero character.
+** ^If the 3rd parameter to the sqlite3_result_text* interfaces
+** is non-negative, then as many bytes (not characters) of the text
+** pointed to by the 2nd parameter are taken as the application-defined
+** function result. If the 3rd parameter is non-negative, then it
+** must be the byte offset into the string where the NUL terminator would
+** appear if the string where NUL terminated. If any NUL characters occur
+** in the string at a byte offset that is less than the value of the 3rd
+** parameter, then the resulting string will contain embedded NULs and the
+** result of expressions operating on strings with embedded NULs is undefined.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces
+** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
+** function as the destructor on the text or BLOB result when it has
+** finished using that result.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
+** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
+** assumes that the text or BLOB result is in constant space and does not
+** copy the content of the parameter nor call a destructor on the content
+** when it has finished using that result.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces
+** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
+** then SQLite makes a copy of the result into space obtained
+** from [sqlite3_malloc()] before it returns.
+**
+** ^The sqlite3_result_value() interface sets the result of
+** the application-defined function to be a copy of the
+** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
+** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
+** so that the [sqlite3_value] specified in the parameter may change or
+** be deallocated after sqlite3_result_value() returns without harm.
+** ^A [protected sqlite3_value] object may always be used where an
+** [unprotected sqlite3_value] object is required, so either
+** kind of [sqlite3_value] object can be used with this interface.
+**
+** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
+** SQL NULL value, just like [sqlite3_result_null(C)], except that it
+** also associates the host-language pointer P or type T with that
+** NULL value such that the pointer can be retrieved within an
+** [application-defined SQL function] using [sqlite3_value_pointer()].
+** ^If the D parameter is not NULL, then it is a pointer to a destructor
+** for the P parameter. ^SQLite invokes D with P as its only argument
+** when SQLite is finished with P. The T parameter should be a static
+** string and preferably a string literal. The sqlite3_result_pointer()
+** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
+**
+** If these routines are called from within the different thread
+** than the one containing the application-defined function that received
+** the [sqlite3_context] pointer, the results are undefined.
+*/
+SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
+ sqlite3_uint64,void(*)(void*));
+SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
+SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
+SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
+SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
+SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
+SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
+SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
+SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
+SQLITE_API void sqlite3_result_null(sqlite3_context*);
+SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
+ void(*)(void*), unsigned char encoding);
+SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
+SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
+SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
+SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
+SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
+SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
+
+
+/*
+** CAPI3REF: Setting The Subtype Of An SQL Function
+** METHOD: sqlite3_context
+**
+** The sqlite3_result_subtype(C,T) function causes the subtype of
+** the result from the [application-defined SQL function] with
+** [sqlite3_context] C to be the value T. Only the lower 8 bits
+** of the subtype T are preserved in current versions of SQLite;
+** higher order bits are discarded.
+** The number of subtype bytes preserved by SQLite might increase
+** in future releases of SQLite.
+*/
+SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
+
+/*
+** CAPI3REF: Define New Collating Sequences
+** METHOD: sqlite3
+**
+** ^These functions add, remove, or modify a [collation] associated
+** with the [database connection] specified as the first argument.
+**
+** ^The name of the collation is a UTF-8 string
+** for sqlite3_create_collation() and sqlite3_create_collation_v2()
+** and a UTF-16 string in native byte order for sqlite3_create_collation16().
+** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
+** considered to be the same name.
+**
+** ^(The third argument (eTextRep) must be one of the constants:
+**
+**
[SQLITE_UTF8],
+**
[SQLITE_UTF16LE],
+**
[SQLITE_UTF16BE],
+**
[SQLITE_UTF16], or
+**
[SQLITE_UTF16_ALIGNED].
+**
)^
+** ^The eTextRep argument determines the encoding of strings passed
+** to the collating function callback, xCallback.
+** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
+** force strings to be UTF16 with native byte order.
+** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
+** on an even byte address.
+**
+** ^The fourth argument, pArg, is an application data pointer that is passed
+** through as the first argument to the collating function callback.
+**
+** ^The fifth argument, xCallback, is a pointer to the collating function.
+** ^Multiple collating functions can be registered using the same name but
+** with different eTextRep parameters and SQLite will use whichever
+** function requires the least amount of data transformation.
+** ^If the xCallback argument is NULL then the collating function is
+** deleted. ^When all collating functions having the same name are deleted,
+** that collation is no longer usable.
+**
+** ^The collating function callback is invoked with a copy of the pArg
+** application data pointer and with two strings in the encoding specified
+** by the eTextRep argument. The collating function must return an
+** integer that is negative, zero, or positive
+** if the first string is less than, equal to, or greater than the second,
+** respectively. A collating function must always return the same answer
+** given the same inputs. If two or more collating functions are registered
+** to the same collation name (using different eTextRep values) then all
+** must give an equivalent answer when invoked with equivalent strings.
+** The collating function must obey the following properties for all
+** strings A, B, and C:
+**
+**
+**
If A==B then B==A.
+**
If A==B and B==C then A==C.
+**
If A<B THEN B>A.
+**
If A<B and B<C then A<C.
+**
+**
+** If a collating function fails any of the above constraints and that
+** collating function is registered and used, then the behavior of SQLite
+** is undefined.
+**
+** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
+** with the addition that the xDestroy callback is invoked on pArg when
+** the collating function is deleted.
+** ^Collating functions are deleted when they are overridden by later
+** calls to the collation creation functions or when the
+** [database connection] is closed using [sqlite3_close()].
+**
+** ^The xDestroy callback is not called if the
+** sqlite3_create_collation_v2() function fails. Applications that invoke
+** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
+** check the return code and dispose of the application data pointer
+** themselves rather than expecting SQLite to deal with it for them.
+** This is different from every other SQLite interface. The inconsistency
+** is unfortunate but cannot be changed without breaking backwards
+** compatibility.
+**
+** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
+*/
+SQLITE_API int sqlite3_create_collation(
+ sqlite3*,
+ const char *zName,
+ int eTextRep,
+ void *pArg,
+ int(*xCompare)(void*,int,const void*,int,const void*)
+);
+SQLITE_API int sqlite3_create_collation_v2(
+ sqlite3*,
+ const char *zName,
+ int eTextRep,
+ void *pArg,
+ int(*xCompare)(void*,int,const void*,int,const void*),
+ void(*xDestroy)(void*)
+);
+SQLITE_API int sqlite3_create_collation16(
+ sqlite3*,
+ const void *zName,
+ int eTextRep,
+ void *pArg,
+ int(*xCompare)(void*,int,const void*,int,const void*)
+);
+
+/*
+** CAPI3REF: Collation Needed Callbacks
+** METHOD: sqlite3
+**
+** ^To avoid having to register all collation sequences before a database
+** can be used, a single callback function may be registered with the
+** [database connection] to be invoked whenever an undefined collation
+** sequence is required.
+**
+** ^If the function is registered using the sqlite3_collation_needed() API,
+** then it is passed the names of undefined collation sequences as strings
+** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
+** the names are passed as UTF-16 in machine native byte order.
+** ^A call to either function replaces the existing collation-needed callback.
+**
+** ^(When the callback is invoked, the first argument passed is a copy
+** of the second argument to sqlite3_collation_needed() or
+** sqlite3_collation_needed16(). The second argument is the database
+** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
+** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
+** sequence function required. The fourth parameter is the name of the
+** required collation sequence.)^
+**
+** The callback function should register the desired collation using
+** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
+** [sqlite3_create_collation_v2()].
+*/
+SQLITE_API int sqlite3_collation_needed(
+ sqlite3*,
+ void*,
+ void(*)(void*,sqlite3*,int eTextRep,const char*)
+);
+SQLITE_API int sqlite3_collation_needed16(
+ sqlite3*,
+ void*,
+ void(*)(void*,sqlite3*,int eTextRep,const void*)
+);
+
+#ifdef SQLITE_HAS_CODEC
+/*
+** Specify the key for an encrypted database. This routine should be
+** called right after sqlite3_open().
+**
+** The code to implement this API is not available in the public release
+** of SQLite.
+*/
+SQLITE_API int sqlite3_key(
+ sqlite3 *db, /* Database to be rekeyed */
+ const void *pKey, int nKey /* The key */
+);
+SQLITE_API int sqlite3_key_v2(
+ sqlite3 *db, /* Database to be rekeyed */
+ const char *zDbName, /* Name of the database */
+ const void *pKey, int nKey /* The key */
+);
+
+/*
+** Change the key on an open database. If the current database is not
+** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
+** database is decrypted.
+**
+** The code to implement this API is not available in the public release
+** of SQLite.
+*/
+SQLITE_API int sqlite3_rekey(
+ sqlite3 *db, /* Database to be rekeyed */
+ const void *pKey, int nKey /* The new key */
+);
+SQLITE_API int sqlite3_rekey_v2(
+ sqlite3 *db, /* Database to be rekeyed */
+ const char *zDbName, /* Name of the database */
+ const void *pKey, int nKey /* The new key */
+);
+
+/*
+** Specify the activation key for a SEE database. Unless
+** activated, none of the SEE routines will work.
+*/
+SQLITE_API void sqlite3_activate_see(
+ const char *zPassPhrase /* Activation phrase */
+);
+#endif
+
+#ifdef SQLITE_ENABLE_CEROD
+/*
+** Specify the activation key for a CEROD database. Unless
+** activated, none of the CEROD routines will work.
+*/
+SQLITE_API void sqlite3_activate_cerod(
+ const char *zPassPhrase /* Activation phrase */
+);
+#endif
+
+/*
+** CAPI3REF: Suspend Execution For A Short Time
+**
+** The sqlite3_sleep() function causes the current thread to suspend execution
+** for at least a number of milliseconds specified in its parameter.
+**
+** If the operating system does not support sleep requests with
+** millisecond time resolution, then the time will be rounded up to
+** the nearest second. The number of milliseconds of sleep actually
+** requested from the operating system is returned.
+**
+** ^SQLite implements this interface by calling the xSleep()
+** method of the default [sqlite3_vfs] object. If the xSleep() method
+** of the default VFS is not implemented correctly, or not implemented at
+** all, then the behavior of sqlite3_sleep() may deviate from the description
+** in the previous paragraphs.
+*/
+SQLITE_API int sqlite3_sleep(int);
+
+/*
+** CAPI3REF: Name Of The Folder Holding Temporary Files
+**
+** ^(If this global variable is made to point to a string which is
+** the name of a folder (a.k.a. directory), then all temporary files
+** created by SQLite when using a built-in [sqlite3_vfs | VFS]
+** will be placed in that directory.)^ ^If this variable
+** is a NULL pointer, then SQLite performs a search for an appropriate
+** temporary file directory.
+**
+** Applications are strongly discouraged from using this global variable.
+** It is required to set a temporary folder on Windows Runtime (WinRT).
+** But for all other platforms, it is highly recommended that applications
+** neither read nor write this variable. This global variable is a relic
+** that exists for backwards compatibility of legacy applications and should
+** be avoided in new projects.
+**
+** It is not safe to read or modify this variable in more than one
+** thread at a time. It is not safe to read or modify this variable
+** if a [database connection] is being used at the same time in a separate
+** thread.
+** It is intended that this variable be set once
+** as part of process initialization and before any SQLite interface
+** routines have been called and that this variable remain unchanged
+** thereafter.
+**
+** ^The [temp_store_directory pragma] may modify this variable and cause
+** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
+** the [temp_store_directory pragma] always assumes that any string
+** that this variable points to is held in memory obtained from
+** [sqlite3_malloc] and the pragma may attempt to free that memory
+** using [sqlite3_free].
+** Hence, if this variable is modified directly, either it should be
+** made NULL or made to point to memory obtained from [sqlite3_malloc]
+** or else the use of the [temp_store_directory pragma] should be avoided.
+** Except when requested by the [temp_store_directory pragma], SQLite
+** does not free the memory that sqlite3_temp_directory points to. If
+** the application wants that memory to be freed, it must do
+** so itself, taking care to only do so after all [database connection]
+** objects have been destroyed.
+**
+** Note to Windows Runtime users: The temporary directory must be set
+** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
+** features that require the use of temporary files may fail. Here is an
+** example of how to do this using C++ with the Windows Runtime:
+**
+**
+*/
+SQLITE_API char *sqlite3_temp_directory;
+
+/*
+** CAPI3REF: Name Of The Folder Holding Database Files
+**
+** ^(If this global variable is made to point to a string which is
+** the name of a folder (a.k.a. directory), then all database files
+** specified with a relative pathname and created or accessed by
+** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
+** to be relative to that directory.)^ ^If this variable is a NULL
+** pointer, then SQLite assumes that all database files specified
+** with a relative pathname are relative to the current directory
+** for the process. Only the windows VFS makes use of this global
+** variable; it is ignored by the unix VFS.
+**
+** Changing the value of this variable while a database connection is
+** open can result in a corrupt database.
+**
+** It is not safe to read or modify this variable in more than one
+** thread at a time. It is not safe to read or modify this variable
+** if a [database connection] is being used at the same time in a separate
+** thread.
+** It is intended that this variable be set once
+** as part of process initialization and before any SQLite interface
+** routines have been called and that this variable remain unchanged
+** thereafter.
+**
+** ^The [data_store_directory pragma] may modify this variable and cause
+** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
+** the [data_store_directory pragma] always assumes that any string
+** that this variable points to is held in memory obtained from
+** [sqlite3_malloc] and the pragma may attempt to free that memory
+** using [sqlite3_free].
+** Hence, if this variable is modified directly, either it should be
+** made NULL or made to point to memory obtained from [sqlite3_malloc]
+** or else the use of the [data_store_directory pragma] should be avoided.
+*/
+SQLITE_API char *sqlite3_data_directory;
+
+/*
+** CAPI3REF: Win32 Specific Interface
+**
+** These interfaces are available only on Windows. The
+** [sqlite3_win32_set_directory] interface is used to set the value associated
+** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to
+** zValue, depending on the value of the type parameter. The zValue parameter
+** should be NULL to cause the previous value to be freed via [sqlite3_free];
+** a non-NULL value will be copied into memory obtained from [sqlite3_malloc]
+** prior to being used. The [sqlite3_win32_set_directory] interface returns
+** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported,
+** or [SQLITE_NOMEM] if memory could not be allocated. The value of the
+** [sqlite3_data_directory] variable is intended to act as a replacement for
+** the current directory on the sub-platforms of Win32 where that concept is
+** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and
+** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the
+** sqlite3_win32_set_directory interface except the string parameter must be
+** UTF-8 or UTF-16, respectively.
+*/
+SQLITE_API int sqlite3_win32_set_directory(
+ unsigned long type, /* Identifier for directory being set or reset */
+ void *zValue /* New value for directory being set or reset */
+);
+SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue);
+SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue);
+
+/*
+** CAPI3REF: Win32 Directory Types
+**
+** These macros are only available on Windows. They define the allowed values
+** for the type argument to the [sqlite3_win32_set_directory] interface.
+*/
+#define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1
+#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2
+
+/*
+** CAPI3REF: Test For Auto-Commit Mode
+** KEYWORDS: {autocommit mode}
+** METHOD: sqlite3
+**
+** ^The sqlite3_get_autocommit() interface returns non-zero or
+** zero if the given database connection is or is not in autocommit mode,
+** respectively. ^Autocommit mode is on by default.
+** ^Autocommit mode is disabled by a [BEGIN] statement.
+** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
+**
+** If certain kinds of errors occur on a statement within a multi-statement
+** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
+** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
+** transaction might be rolled back automatically. The only way to
+** find out whether SQLite automatically rolled back the transaction after
+** an error is to use this function.
+**
+** If another thread changes the autocommit status of the database
+** connection while this routine is running, then the return value
+** is undefined.
+*/
+SQLITE_API int sqlite3_get_autocommit(sqlite3*);
+
+/*
+** CAPI3REF: Find The Database Handle Of A Prepared Statement
+** METHOD: sqlite3_stmt
+**
+** ^The sqlite3_db_handle interface returns the [database connection] handle
+** to which a [prepared statement] belongs. ^The [database connection]
+** returned by sqlite3_db_handle is the same [database connection]
+** that was the first argument
+** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
+** create the statement in the first place.
+*/
+SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Return The Filename For A Database Connection
+** METHOD: sqlite3
+**
+** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
+** associated with database N of connection D. ^The main database file
+** has the name "main". If there is no attached database N on the database
+** connection D, or if database N is a temporary or in-memory database, then
+** a NULL pointer is returned.
+**
+** ^The filename returned by this function is the output of the
+** xFullPathname method of the [VFS]. ^In other words, the filename
+** will be an absolute pathname, even if the filename used
+** to open the database originally was a URI or relative pathname.
+*/
+SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
+
+/*
+** CAPI3REF: Determine if a database is read-only
+** METHOD: sqlite3
+**
+** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
+** of connection D is read-only, 0 if it is read/write, or -1 if N is not
+** the name of a database on connection D.
+*/
+SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
+
+/*
+** CAPI3REF: Find the next prepared statement
+** METHOD: sqlite3
+**
+** ^This interface returns a pointer to the next [prepared statement] after
+** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
+** then this interface returns a pointer to the first prepared statement
+** associated with the database connection pDb. ^If no prepared statement
+** satisfies the conditions of this routine, it returns NULL.
+**
+** The [database connection] pointer D in a call to
+** [sqlite3_next_stmt(D,S)] must refer to an open database
+** connection and in particular must not be a NULL pointer.
+*/
+SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Commit And Rollback Notification Callbacks
+** METHOD: sqlite3
+**
+** ^The sqlite3_commit_hook() interface registers a callback
+** function to be invoked whenever a transaction is [COMMIT | committed].
+** ^Any callback set by a previous call to sqlite3_commit_hook()
+** for the same database connection is overridden.
+** ^The sqlite3_rollback_hook() interface registers a callback
+** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
+** ^Any callback set by a previous call to sqlite3_rollback_hook()
+** for the same database connection is overridden.
+** ^The pArg argument is passed through to the callback.
+** ^If the callback on a commit hook function returns non-zero,
+** then the commit is converted into a rollback.
+**
+** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
+** return the P argument from the previous call of the same function
+** on the same [database connection] D, or NULL for
+** the first call for each function on D.
+**
+** The commit and rollback hook callbacks are not reentrant.
+** The callback implementation must not do anything that will modify
+** the database connection that invoked the callback. Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the commit
+** or rollback hook in the first place.
+** Note that running any other SQL statements, including SELECT statements,
+** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
+** the database connections for the meaning of "modify" in this paragraph.
+**
+** ^Registering a NULL function disables the callback.
+**
+** ^When the commit hook callback routine returns zero, the [COMMIT]
+** operation is allowed to continue normally. ^If the commit hook
+** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
+** ^The rollback hook is invoked on a rollback that results from a commit
+** hook returning non-zero, just as it would be with any other rollback.
+**
+** ^For the purposes of this API, a transaction is said to have been
+** rolled back if an explicit "ROLLBACK" statement is executed, or
+** an error or constraint causes an implicit rollback to occur.
+** ^The rollback callback is not invoked if a transaction is
+** automatically rolled back because the database connection is closed.
+**
+** See also the [sqlite3_update_hook()] interface.
+*/
+SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
+SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
+
+/*
+** CAPI3REF: Data Change Notification Callbacks
+** METHOD: sqlite3
+**
+** ^The sqlite3_update_hook() interface registers a callback function
+** with the [database connection] identified by the first argument
+** to be invoked whenever a row is updated, inserted or deleted in
+** a [rowid table].
+** ^Any callback set by a previous call to this function
+** for the same database connection is overridden.
+**
+** ^The second argument is a pointer to the function to invoke when a
+** row is updated, inserted or deleted in a rowid table.
+** ^The first argument to the callback is a copy of the third argument
+** to sqlite3_update_hook().
+** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
+** or [SQLITE_UPDATE], depending on the operation that caused the callback
+** to be invoked.
+** ^The third and fourth arguments to the callback contain pointers to the
+** database and table name containing the affected row.
+** ^The final callback parameter is the [rowid] of the row.
+** ^In the case of an update, this is the [rowid] after the update takes place.
+**
+** ^(The update hook is not invoked when internal system tables are
+** modified (i.e. sqlite_master and sqlite_sequence).)^
+** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
+**
+** ^In the current implementation, the update hook
+** is not invoked when conflicting rows are deleted because of an
+** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
+** invoked when rows are deleted using the [truncate optimization].
+** The exceptions defined in this paragraph might change in a future
+** release of SQLite.
+**
+** The update hook implementation must not do anything that will modify
+** the database connection that invoked the update hook. Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the update hook.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+** ^The sqlite3_update_hook(D,C,P) function
+** returns the P argument from the previous call
+** on the same [database connection] D, or NULL for
+** the first call on D.
+**
+** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
+** and [sqlite3_preupdate_hook()] interfaces.
+*/
+SQLITE_API void *sqlite3_update_hook(
+ sqlite3*,
+ void(*)(void *,int ,char const *,char const *,sqlite3_int64),
+ void*
+);
+
+/*
+** CAPI3REF: Enable Or Disable Shared Pager Cache
+**
+** ^(This routine enables or disables the sharing of the database cache
+** and schema data structures between [database connection | connections]
+** to the same database. Sharing is enabled if the argument is true
+** and disabled if the argument is false.)^
+**
+** ^Cache sharing is enabled and disabled for an entire process.
+** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
+** In prior versions of SQLite,
+** sharing was enabled or disabled for each thread separately.
+**
+** ^(The cache sharing mode set by this interface effects all subsequent
+** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
+** Existing database connections continue use the sharing mode
+** that was in effect at the time they were opened.)^
+**
+** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
+** successfully. An [error code] is returned otherwise.)^
+**
+** ^Shared cache is disabled by default. But this might change in
+** future releases of SQLite. Applications that care about shared
+** cache setting should set it explicitly.
+**
+** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
+** and will always return SQLITE_MISUSE. On those systems,
+** shared cache mode should be enabled per-database connection via
+** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
+**
+** This interface is threadsafe on processors where writing a
+** 32-bit integer is atomic.
+**
+** See Also: [SQLite Shared-Cache Mode]
+*/
+SQLITE_API int sqlite3_enable_shared_cache(int);
+
+/*
+** CAPI3REF: Attempt To Free Heap Memory
+**
+** ^The sqlite3_release_memory() interface attempts to free N bytes
+** of heap memory by deallocating non-essential memory allocations
+** held by the database library. Memory used to cache database
+** pages to improve performance is an example of non-essential memory.
+** ^sqlite3_release_memory() returns the number of bytes actually freed,
+** which might be more or less than the amount requested.
+** ^The sqlite3_release_memory() routine is a no-op returning zero
+** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+**
+** See also: [sqlite3_db_release_memory()]
+*/
+SQLITE_API int sqlite3_release_memory(int);
+
+/*
+** CAPI3REF: Free Memory Used By A Database Connection
+** METHOD: sqlite3
+**
+** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
+** memory as possible from database connection D. Unlike the
+** [sqlite3_release_memory()] interface, this interface is in effect even
+** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
+** omitted.
+**
+** See also: [sqlite3_release_memory()]
+*/
+SQLITE_API int sqlite3_db_release_memory(sqlite3*);
+
+/*
+** CAPI3REF: Impose A Limit On Heap Size
+**
+** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
+** soft limit on the amount of heap memory that may be allocated by SQLite.
+** ^SQLite strives to keep heap memory utilization below the soft heap
+** limit by reducing the number of pages held in the page cache
+** as heap memory usages approaches the limit.
+** ^The soft heap limit is "soft" because even though SQLite strives to stay
+** below the limit, it will exceed the limit rather than generate
+** an [SQLITE_NOMEM] error. In other words, the soft heap limit
+** is advisory only.
+**
+** ^The return value from sqlite3_soft_heap_limit64() is the size of
+** the soft heap limit prior to the call, or negative in the case of an
+** error. ^If the argument N is negative
+** then no change is made to the soft heap limit. Hence, the current
+** size of the soft heap limit can be determined by invoking
+** sqlite3_soft_heap_limit64() with a negative argument.
+**
+** ^If the argument N is zero then the soft heap limit is disabled.
+**
+** ^(The soft heap limit is not enforced in the current implementation
+** if one or more of following conditions are true:
+**
+**
+**
The soft heap limit is set to zero.
+**
Memory accounting is disabled using a combination of the
+** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
+** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
+**
An alternative page cache implementation is specified using
+** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
+**
The page cache allocates from its own memory pool supplied
+** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
+** from the heap.
+**
)^
+**
+** Beginning with SQLite [version 3.7.3] ([dateof:3.7.3]),
+** the soft heap limit is enforced
+** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
+** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
+** the soft heap limit is enforced on every memory allocation. Without
+** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
+** when memory is allocated by the page cache. Testing suggests that because
+** the page cache is the predominate memory user in SQLite, most
+** applications will achieve adequate soft heap limit enforcement without
+** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+**
+** The circumstances under which SQLite will enforce the soft heap limit may
+** changes in future releases of SQLite.
+*/
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
+
+/*
+** CAPI3REF: Deprecated Soft Heap Limit Interface
+** DEPRECATED
+**
+** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
+** interface. This routine is provided for historical compatibility
+** only. All new applications should use the
+** [sqlite3_soft_heap_limit64()] interface rather than this one.
+*/
+SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
+
+
+/*
+** CAPI3REF: Extract Metadata About A Column Of A Table
+** METHOD: sqlite3
+**
+** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
+** information about column C of table T in database D
+** on [database connection] X.)^ ^The sqlite3_table_column_metadata()
+** interface returns SQLITE_OK and fills in the non-NULL pointers in
+** the final five arguments with appropriate values if the specified
+** column exists. ^The sqlite3_table_column_metadata() interface returns
+** SQLITE_ERROR and if the specified column does not exist.
+** ^If the column-name parameter to sqlite3_table_column_metadata() is a
+** NULL pointer, then this routine simply checks for the existence of the
+** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
+** does not. If the table name parameter T in a call to
+** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
+** undefined behavior.
+**
+** ^The column is identified by the second, third and fourth parameters to
+** this function. ^(The second parameter is either the name of the database
+** (i.e. "main", "temp", or an attached database) containing the specified
+** table or NULL.)^ ^If it is NULL, then all attached databases are searched
+** for the table using the same algorithm used by the database engine to
+** resolve unqualified table references.
+**
+** ^The third and fourth parameters to this function are the table and column
+** name of the desired column, respectively.
+**
+** ^Metadata is returned by writing to the memory locations passed as the 5th
+** and subsequent parameters to this function. ^Any of these arguments may be
+** NULL, in which case the corresponding element of metadata is omitted.
+**
+** ^(
+**
+**
Parameter
Output Type
Description
+**
+**
5th
const char*
Data type
+**
6th
const char*
Name of default collation sequence
+**
7th
int
True if column has a NOT NULL constraint
+**
8th
int
True if column is part of the PRIMARY KEY
+**
9th
int
True if column is [AUTOINCREMENT]
+**
+**
)^
+**
+** ^The memory pointed to by the character pointers returned for the
+** declaration type and collation sequence is valid until the next
+** call to any SQLite API function.
+**
+** ^If the specified table is actually a view, an [error code] is returned.
+**
+** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
+** is not a [WITHOUT ROWID] table and an
+** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
+** parameters are set for the explicitly declared column. ^(If there is no
+** [INTEGER PRIMARY KEY] column, then the outputs
+** for the [rowid] are set as follows:
+**
+**
+** data type: "INTEGER"
+** collation sequence: "BINARY"
+** not null: 0
+** primary key: 1
+** auto increment: 0
+**
)^
+**
+** ^This function causes all database schemas to be read from disk and
+** parsed, if that has not already been done, and returns an error if
+** any errors are encountered while loading the schema.
+*/
+SQLITE_API int sqlite3_table_column_metadata(
+ sqlite3 *db, /* Connection handle */
+ const char *zDbName, /* Database name or NULL */
+ const char *zTableName, /* Table name */
+ const char *zColumnName, /* Column name */
+ char const **pzDataType, /* OUTPUT: Declared data type */
+ char const **pzCollSeq, /* OUTPUT: Collation sequence name */
+ int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
+ int *pPrimaryKey, /* OUTPUT: True if column part of PK */
+ int *pAutoinc /* OUTPUT: True if column is auto-increment */
+);
+
+/*
+** CAPI3REF: Load An Extension
+** METHOD: sqlite3
+**
+** ^This interface loads an SQLite extension library from the named file.
+**
+** ^The sqlite3_load_extension() interface attempts to load an
+** [SQLite extension] library contained in the file zFile. If
+** the file cannot be loaded directly, attempts are made to load
+** with various operating-system specific extensions added.
+** So for example, if "samplelib" cannot be loaded, then names like
+** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
+** be tried also.
+**
+** ^The entry point is zProc.
+** ^(zProc may be 0, in which case SQLite will try to come up with an
+** entry point name on its own. It first tries "sqlite3_extension_init".
+** If that does not work, it constructs a name "sqlite3_X_init" where the
+** X is consists of the lower-case equivalent of all ASCII alphabetic
+** characters in the filename from the last "/" to the first following
+** "." and omitting any initial "lib".)^
+** ^The sqlite3_load_extension() interface returns
+** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
+** ^If an error occurs and pzErrMsg is not 0, then the
+** [sqlite3_load_extension()] interface shall attempt to
+** fill *pzErrMsg with error message text stored in memory
+** obtained from [sqlite3_malloc()]. The calling function
+** should free this memory by calling [sqlite3_free()].
+**
+** ^Extension loading must be enabled using
+** [sqlite3_enable_load_extension()] or
+** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
+** prior to calling this API,
+** otherwise an error will be returned.
+**
+** Security warning: It is recommended that the
+** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
+** interface. The use of the [sqlite3_enable_load_extension()] interface
+** should be avoided. This will keep the SQL function [load_extension()]
+** disabled and prevent SQL injections from giving attackers
+** access to extension loading capabilities.
+**
+** See also the [load_extension() SQL function].
+*/
+SQLITE_API int sqlite3_load_extension(
+ sqlite3 *db, /* Load the extension into this database connection */
+ const char *zFile, /* Name of the shared library containing extension */
+ const char *zProc, /* Entry point. Derived from zFile if 0 */
+ char **pzErrMsg /* Put error message here if not 0 */
+);
+
+/*
+** CAPI3REF: Enable Or Disable Extension Loading
+** METHOD: sqlite3
+**
+** ^So as not to open security holes in older applications that are
+** unprepared to deal with [extension loading], and as a means of disabling
+** [extension loading] while evaluating user-entered SQL, the following API
+** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
+**
+** ^Extension loading is off by default.
+** ^Call the sqlite3_enable_load_extension() routine with onoff==1
+** to turn extension loading on and call it with onoff==0 to turn
+** it back off again.
+**
+** ^This interface enables or disables both the C-API
+** [sqlite3_load_extension()] and the SQL function [load_extension()].
+** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
+** to enable or disable only the C-API.)^
+**
+** Security warning: It is recommended that extension loading
+** be disabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
+** rather than this interface, so the [load_extension()] SQL function
+** remains disabled. This will prevent SQL injections from giving attackers
+** access to extension loading capabilities.
+*/
+SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
+
+/*
+** CAPI3REF: Automatically Load Statically Linked Extensions
+**
+** ^This interface causes the xEntryPoint() function to be invoked for
+** each new [database connection] that is created. The idea here is that
+** xEntryPoint() is the entry point for a statically linked [SQLite extension]
+** that is to be automatically loaded into all new database connections.
+**
+** ^(Even though the function prototype shows that xEntryPoint() takes
+** no arguments and returns void, SQLite invokes xEntryPoint() with three
+** arguments and expects an integer result as if the signature of the
+** entry point where as follows:
+**
+**
)^
+**
+** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
+** point to an appropriate error message (obtained from [sqlite3_mprintf()])
+** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
+** is NULL before calling the xEntryPoint(). ^SQLite will invoke
+** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
+** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
+** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
+**
+** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
+** on the list of automatic extensions is a harmless no-op. ^No entry point
+** will be called more than once for each database connection that is opened.
+**
+** See also: [sqlite3_reset_auto_extension()]
+** and [sqlite3_cancel_auto_extension()]
+*/
+SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
+
+/*
+** CAPI3REF: Cancel Automatic Extension Loading
+**
+** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
+** initialization routine X that was registered using a prior call to
+** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
+** routine returns 1 if initialization routine X was successfully
+** unregistered and it returns 0 if X was not on the list of initialization
+** routines.
+*/
+SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
+
+/*
+** CAPI3REF: Reset Automatic Extension Loading
+**
+** ^This interface disables all automatic extensions previously
+** registered using [sqlite3_auto_extension()].
+*/
+SQLITE_API void sqlite3_reset_auto_extension(void);
+
+/*
+** The interface to the virtual-table mechanism is currently considered
+** to be experimental. The interface might change in incompatible ways.
+** If this is a problem for you, do not use the interface at this time.
+**
+** When the virtual-table mechanism stabilizes, we will declare the
+** interface fixed, support it indefinitely, and remove this comment.
+*/
+
+/*
+** Structures used by the virtual table interface
+*/
+typedef struct sqlite3_vtab sqlite3_vtab;
+typedef struct sqlite3_index_info sqlite3_index_info;
+typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
+typedef struct sqlite3_module sqlite3_module;
+
+/*
+** CAPI3REF: Virtual Table Object
+** KEYWORDS: sqlite3_module {virtual table module}
+**
+** This structure, sometimes called a "virtual table module",
+** defines the implementation of a [virtual tables].
+** This structure consists mostly of methods for the module.
+**
+** ^A virtual table module is created by filling in a persistent
+** instance of this structure and passing a pointer to that instance
+** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
+** ^The registration remains valid until it is replaced by a different
+** module or until the [database connection] closes. The content
+** of this structure must not change while it is registered with
+** any database connection.
+*/
+struct sqlite3_module {
+ int iVersion;
+ int (*xCreate)(sqlite3*, void *pAux,
+ int argc, const char *const*argv,
+ sqlite3_vtab **ppVTab, char**);
+ int (*xConnect)(sqlite3*, void *pAux,
+ int argc, const char *const*argv,
+ sqlite3_vtab **ppVTab, char**);
+ int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
+ int (*xDisconnect)(sqlite3_vtab *pVTab);
+ int (*xDestroy)(sqlite3_vtab *pVTab);
+ int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
+ int (*xClose)(sqlite3_vtab_cursor*);
+ int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
+ int argc, sqlite3_value **argv);
+ int (*xNext)(sqlite3_vtab_cursor*);
+ int (*xEof)(sqlite3_vtab_cursor*);
+ int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
+ int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
+ int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
+ int (*xBegin)(sqlite3_vtab *pVTab);
+ int (*xSync)(sqlite3_vtab *pVTab);
+ int (*xCommit)(sqlite3_vtab *pVTab);
+ int (*xRollback)(sqlite3_vtab *pVTab);
+ int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
+ void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
+ void **ppArg);
+ int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
+ /* The methods above are in version 1 of the sqlite_module object. Those
+ ** below are for version 2 and greater. */
+ int (*xSavepoint)(sqlite3_vtab *pVTab, int);
+ int (*xRelease)(sqlite3_vtab *pVTab, int);
+ int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
+};
+
+/*
+** CAPI3REF: Virtual Table Indexing Information
+** KEYWORDS: sqlite3_index_info
+**
+** The sqlite3_index_info structure and its substructures is used as part
+** of the [virtual table] interface to
+** pass information into and receive the reply from the [xBestIndex]
+** method of a [virtual table module]. The fields under **Inputs** are the
+** inputs to xBestIndex and are read-only. xBestIndex inserts its
+** results into the **Outputs** fields.
+**
+** ^(The aConstraint[] array records WHERE clause constraints of the form:
+**
+**
column OP expr
+**
+** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
+** stored in aConstraint[].op using one of the
+** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
+** ^(The index of the column is stored in
+** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
+** expr on the right-hand side can be evaluated (and thus the constraint
+** is usable) and false if it cannot.)^
+**
+** ^The optimizer automatically inverts terms of the form "expr OP column"
+** and makes other simplifications to the WHERE clause in an attempt to
+** get as many WHERE clause terms into the form shown above as possible.
+** ^The aConstraint[] array only reports WHERE clause terms that are
+** relevant to the particular virtual table being queried.
+**
+** ^Information about the ORDER BY clause is stored in aOrderBy[].
+** ^Each term of aOrderBy records a column of the ORDER BY clause.
+**
+** The colUsed field indicates which columns of the virtual table may be
+** required by the current scan. Virtual table columns are numbered from
+** zero in the order in which they appear within the CREATE TABLE statement
+** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
+** the corresponding bit is set within the colUsed mask if the column may be
+** required by SQLite. If the table has at least 64 columns and any column
+** to the right of the first 63 is required, then bit 63 of colUsed is also
+** set. In other words, column iCol may be required if the expression
+** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
+** non-zero.
+**
+** The [xBestIndex] method must fill aConstraintUsage[] with information
+** about what parameters to pass to xFilter. ^If argvIndex>0 then
+** the right-hand side of the corresponding aConstraint[] is evaluated
+** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
+** is true, then the constraint is assumed to be fully handled by the
+** virtual table and is not checked again by SQLite.)^
+**
+** ^The idxNum and idxPtr values are recorded and passed into the
+** [xFilter] method.
+** ^[sqlite3_free()] is used to free idxPtr if and only if
+** needToFreeIdxPtr is true.
+**
+** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
+** the correct order to satisfy the ORDER BY clause so that no separate
+** sorting step is required.
+**
+** ^The estimatedCost value is an estimate of the cost of a particular
+** strategy. A cost of N indicates that the cost of the strategy is similar
+** to a linear scan of an SQLite table with N rows. A cost of log(N)
+** indicates that the expense of the operation is similar to that of a
+** binary search on a unique indexed field of an SQLite table with N rows.
+**
+** ^The estimatedRows value is an estimate of the number of rows that
+** will be returned by the strategy.
+**
+** The xBestIndex method may optionally populate the idxFlags field with a
+** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
+** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
+** assumes that the strategy may visit at most one row.
+**
+** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
+** SQLite also assumes that if a call to the xUpdate() method is made as
+** part of the same statement to delete or update a virtual table row and the
+** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
+** any database changes. In other words, if the xUpdate() returns
+** SQLITE_CONSTRAINT, the database contents must be exactly as they were
+** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
+** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
+** the xUpdate method are automatically rolled back by SQLite.
+**
+** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
+** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
+** If a virtual table extension is
+** used with an SQLite version earlier than 3.8.2, the results of attempting
+** to read or write the estimatedRows field are undefined (but are likely
+** to included crashing the application). The estimatedRows field should
+** therefore only be used if [sqlite3_libversion_number()] returns a
+** value greater than or equal to 3008002. Similarly, the idxFlags field
+** was added for [version 3.9.0] ([dateof:3.9.0]).
+** It may therefore only be used if
+** sqlite3_libversion_number() returns a value greater than or equal to
+** 3009000.
+*/
+struct sqlite3_index_info {
+ /* Inputs */
+ int nConstraint; /* Number of entries in aConstraint */
+ struct sqlite3_index_constraint {
+ int iColumn; /* Column constrained. -1 for ROWID */
+ unsigned char op; /* Constraint operator */
+ unsigned char usable; /* True if this constraint is usable */
+ int iTermOffset; /* Used internally - xBestIndex should ignore */
+ } *aConstraint; /* Table of WHERE clause constraints */
+ int nOrderBy; /* Number of terms in the ORDER BY clause */
+ struct sqlite3_index_orderby {
+ int iColumn; /* Column number */
+ unsigned char desc; /* True for DESC. False for ASC. */
+ } *aOrderBy; /* The ORDER BY clause */
+ /* Outputs */
+ struct sqlite3_index_constraint_usage {
+ int argvIndex; /* if >0, constraint is part of argv to xFilter */
+ unsigned char omit; /* Do not code a test for this constraint */
+ } *aConstraintUsage;
+ int idxNum; /* Number used to identify the index */
+ char *idxStr; /* String, possibly obtained from sqlite3_malloc */
+ int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
+ int orderByConsumed; /* True if output is already ordered */
+ double estimatedCost; /* Estimated cost of using this index */
+ /* Fields below are only available in SQLite 3.8.2 and later */
+ sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
+ /* Fields below are only available in SQLite 3.9.0 and later */
+ int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */
+ /* Fields below are only available in SQLite 3.10.0 and later */
+ sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */
+};
+
+/*
+** CAPI3REF: Virtual Table Scan Flags
+**
+** Virtual table implementations are allowed to set the
+** [sqlite3_index_info].idxFlags field to some combination of
+** these bits.
+*/
+#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */
+
+/*
+** CAPI3REF: Virtual Table Constraint Operator Codes
+**
+** These macros defined the allowed values for the
+** [sqlite3_index_info].aConstraint[].op field. Each value represents
+** an operator that is part of a constraint term in the wHERE clause of
+** a query that uses a [virtual table].
+*/
+#define SQLITE_INDEX_CONSTRAINT_EQ 2
+#define SQLITE_INDEX_CONSTRAINT_GT 4
+#define SQLITE_INDEX_CONSTRAINT_LE 8
+#define SQLITE_INDEX_CONSTRAINT_LT 16
+#define SQLITE_INDEX_CONSTRAINT_GE 32
+#define SQLITE_INDEX_CONSTRAINT_MATCH 64
+#define SQLITE_INDEX_CONSTRAINT_LIKE 65
+#define SQLITE_INDEX_CONSTRAINT_GLOB 66
+#define SQLITE_INDEX_CONSTRAINT_REGEXP 67
+#define SQLITE_INDEX_CONSTRAINT_NE 68
+#define SQLITE_INDEX_CONSTRAINT_ISNOT 69
+#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70
+#define SQLITE_INDEX_CONSTRAINT_ISNULL 71
+#define SQLITE_INDEX_CONSTRAINT_IS 72
+#define SQLITE_INDEX_CONSTRAINT_FUNCTION 150
+
+/*
+** CAPI3REF: Register A Virtual Table Implementation
+** METHOD: sqlite3
+**
+** ^These routines are used to register a new [virtual table module] name.
+** ^Module names must be registered before
+** creating a new [virtual table] using the module and before using a
+** preexisting [virtual table] for the module.
+**
+** ^The module name is registered on the [database connection] specified
+** by the first parameter. ^The name of the module is given by the
+** second parameter. ^The third parameter is a pointer to
+** the implementation of the [virtual table module]. ^The fourth
+** parameter is an arbitrary client data pointer that is passed through
+** into the [xCreate] and [xConnect] methods of the virtual table module
+** when a new virtual table is be being created or reinitialized.
+**
+** ^The sqlite3_create_module_v2() interface has a fifth parameter which
+** is a pointer to a destructor for the pClientData. ^SQLite will
+** invoke the destructor function (if it is not NULL) when SQLite
+** no longer needs the pClientData pointer. ^The destructor will also
+** be invoked if the call to sqlite3_create_module_v2() fails.
+** ^The sqlite3_create_module()
+** interface is equivalent to sqlite3_create_module_v2() with a NULL
+** destructor.
+*/
+SQLITE_API int sqlite3_create_module(
+ sqlite3 *db, /* SQLite connection to register module with */
+ const char *zName, /* Name of the module */
+ const sqlite3_module *p, /* Methods for the module */
+ void *pClientData /* Client data for xCreate/xConnect */
+);
+SQLITE_API int sqlite3_create_module_v2(
+ sqlite3 *db, /* SQLite connection to register module with */
+ const char *zName, /* Name of the module */
+ const sqlite3_module *p, /* Methods for the module */
+ void *pClientData, /* Client data for xCreate/xConnect */
+ void(*xDestroy)(void*) /* Module destructor function */
+);
+
+/*
+** CAPI3REF: Virtual Table Instance Object
+** KEYWORDS: sqlite3_vtab
+**
+** Every [virtual table module] implementation uses a subclass
+** of this object to describe a particular instance
+** of the [virtual table]. Each subclass will
+** be tailored to the specific needs of the module implementation.
+** The purpose of this superclass is to define certain fields that are
+** common to all module implementations.
+**
+** ^Virtual tables methods can set an error message by assigning a
+** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
+** take care that any prior string is freed by a call to [sqlite3_free()]
+** prior to assigning a new string to zErrMsg. ^After the error message
+** is delivered up to the client application, the string will be automatically
+** freed by sqlite3_free() and the zErrMsg field will be zeroed.
+*/
+struct sqlite3_vtab {
+ const sqlite3_module *pModule; /* The module for this virtual table */
+ int nRef; /* Number of open cursors */
+ char *zErrMsg; /* Error message from sqlite3_mprintf() */
+ /* Virtual table implementations will typically add additional fields */
+};
+
+/*
+** CAPI3REF: Virtual Table Cursor Object
+** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
+**
+** Every [virtual table module] implementation uses a subclass of the
+** following structure to describe cursors that point into the
+** [virtual table] and are used
+** to loop through the virtual table. Cursors are created using the
+** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
+** by the [sqlite3_module.xClose | xClose] method. Cursors are used
+** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
+** of the module. Each module implementation will define
+** the content of a cursor structure to suit its own needs.
+**
+** This superclass exists in order to define fields of the cursor that
+** are common to all implementations.
+*/
+struct sqlite3_vtab_cursor {
+ sqlite3_vtab *pVtab; /* Virtual table of this cursor */
+ /* Virtual table implementations will typically add additional fields */
+};
+
+/*
+** CAPI3REF: Declare The Schema Of A Virtual Table
+**
+** ^The [xCreate] and [xConnect] methods of a
+** [virtual table module] call this interface
+** to declare the format (the names and datatypes of the columns) of
+** the virtual tables they implement.
+*/
+SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
+
+/*
+** CAPI3REF: Overload A Function For A Virtual Table
+** METHOD: sqlite3
+**
+** ^(Virtual tables can provide alternative implementations of functions
+** using the [xFindFunction] method of the [virtual table module].
+** But global versions of those functions
+** must exist in order to be overloaded.)^
+**
+** ^(This API makes sure a global version of a function with a particular
+** name and number of parameters exists. If no such function exists
+** before this API is called, a new function is created.)^ ^The implementation
+** of the new function always causes an exception to be thrown. So
+** the new function is not good for anything by itself. Its only
+** purpose is to be a placeholder function that can be overloaded
+** by a [virtual table].
+*/
+SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
+
+/*
+** The interface to the virtual-table mechanism defined above (back up
+** to a comment remarkably similar to this one) is currently considered
+** to be experimental. The interface might change in incompatible ways.
+** If this is a problem for you, do not use the interface at this time.
+**
+** When the virtual-table mechanism stabilizes, we will declare the
+** interface fixed, support it indefinitely, and remove this comment.
+*/
+
+/*
+** CAPI3REF: A Handle To An Open BLOB
+** KEYWORDS: {BLOB handle} {BLOB handles}
+**
+** An instance of this object represents an open BLOB on which
+** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
+** ^Objects of this type are created by [sqlite3_blob_open()]
+** and destroyed by [sqlite3_blob_close()].
+** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
+** can be used to read or write small subsections of the BLOB.
+** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
+*/
+typedef struct sqlite3_blob sqlite3_blob;
+
+/*
+** CAPI3REF: Open A BLOB For Incremental I/O
+** METHOD: sqlite3
+** CONSTRUCTOR: sqlite3_blob
+**
+** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
+** in row iRow, column zColumn, table zTable in database zDb;
+** in other words, the same BLOB that would be selected by:
+**
+**
+** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
+**
)^
+**
+** ^(Parameter zDb is not the filename that contains the database, but
+** rather the symbolic name of the database. For attached databases, this is
+** the name that appears after the AS keyword in the [ATTACH] statement.
+** For the main database file, the database name is "main". For TEMP
+** tables, the database name is "temp".)^
+**
+** ^If the flags parameter is non-zero, then the BLOB is opened for read
+** and write access. ^If the flags parameter is zero, the BLOB is opened for
+** read-only access.
+**
+** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
+** in *ppBlob. Otherwise an [error code] is returned and, unless the error
+** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
+** the API is not misused, it is always safe to call [sqlite3_blob_close()]
+** on *ppBlob after this function it returns.
+**
+** This function fails with SQLITE_ERROR if any of the following are true:
+**
+**
^(Database zDb does not exist)^,
+**
^(Table zTable does not exist within database zDb)^,
+**
^(Table zTable is a WITHOUT ROWID table)^,
+**
^(Column zColumn does not exist)^,
+**
^(Row iRow is not present in the table)^,
+**
^(The specified column of row iRow contains a value that is not
+** a TEXT or BLOB value)^,
+**
^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
+** constraint and the blob is being opened for read/write access)^,
+**
^([foreign key constraints | Foreign key constraints] are enabled,
+** column zColumn is part of a [child key] definition and the blob is
+** being opened for read/write access)^.
+**
+**
+** ^Unless it returns SQLITE_MISUSE, this function sets the
+** [database connection] error code and message accessible via
+** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
+**
+** A BLOB referenced by sqlite3_blob_open() may be read using the
+** [sqlite3_blob_read()] interface and modified by using
+** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a
+** different row of the same table using the [sqlite3_blob_reopen()]
+** interface. However, the column, table, or database of a [BLOB handle]
+** cannot be changed after the [BLOB handle] is opened.
+**
+** ^(If the row that a BLOB handle points to is modified by an
+** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
+** then the BLOB handle is marked as "expired".
+** This is true if any column of the row is changed, even a column
+** other than the one the BLOB handle is open on.)^
+** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
+** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
+** ^(Changes written into a BLOB prior to the BLOB expiring are not
+** rolled back by the expiration of the BLOB. Such changes will eventually
+** commit if the transaction continues to completion.)^
+**
+** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
+** the opened blob. ^The size of a blob may not be changed by this
+** interface. Use the [UPDATE] SQL command to change the size of a
+** blob.
+**
+** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
+** and the built-in [zeroblob] SQL function may be used to create a
+** zero-filled blob to read or write using the incremental-blob interface.
+**
+** To avoid a resource leak, every open [BLOB handle] should eventually
+** be released by a call to [sqlite3_blob_close()].
+**
+** See also: [sqlite3_blob_close()],
+** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
+** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
+*/
+SQLITE_API int sqlite3_blob_open(
+ sqlite3*,
+ const char *zDb,
+ const char *zTable,
+ const char *zColumn,
+ sqlite3_int64 iRow,
+ int flags,
+ sqlite3_blob **ppBlob
+);
+
+/*
+** CAPI3REF: Move a BLOB Handle to a New Row
+** METHOD: sqlite3_blob
+**
+** ^This function is used to move an existing [BLOB handle] so that it points
+** to a different row of the same database table. ^The new row is identified
+** by the rowid value passed as the second argument. Only the row can be
+** changed. ^The database, table and column on which the blob handle is open
+** remain the same. Moving an existing [BLOB handle] to a new row is
+** faster than closing the existing handle and opening a new one.
+**
+** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
+** it must exist and there must be either a blob or text value stored in
+** the nominated column.)^ ^If the new row is not present in the table, or if
+** it does not contain a blob or text value, or if another error occurs, an
+** SQLite error code is returned and the blob handle is considered aborted.
+** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
+** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
+** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
+** always returns zero.
+**
+** ^This function sets the database handle error code and message.
+*/
+SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
+
+/*
+** CAPI3REF: Close A BLOB Handle
+** DESTRUCTOR: sqlite3_blob
+**
+** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
+** unconditionally. Even if this routine returns an error code, the
+** handle is still closed.)^
+**
+** ^If the blob handle being closed was opened for read-write access, and if
+** the database is in auto-commit mode and there are no other open read-write
+** blob handles or active write statements, the current transaction is
+** committed. ^If an error occurs while committing the transaction, an error
+** code is returned and the transaction rolled back.
+**
+** Calling this function with an argument that is not a NULL pointer or an
+** open blob handle results in undefined behaviour. ^Calling this routine
+** with a null pointer (such as would be returned by a failed call to
+** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
+** is passed a valid open blob handle, the values returned by the
+** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
+*/
+SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
+
+/*
+** CAPI3REF: Return The Size Of An Open BLOB
+** METHOD: sqlite3_blob
+**
+** ^Returns the size in bytes of the BLOB accessible via the
+** successfully opened [BLOB handle] in its only argument. ^The
+** incremental blob I/O routines can only read or overwriting existing
+** blob content; they cannot change the size of a blob.
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()]. Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+*/
+SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
+
+/*
+** CAPI3REF: Read Data From A BLOB Incrementally
+** METHOD: sqlite3_blob
+**
+** ^(This function is used to read data from an open [BLOB handle] into a
+** caller-supplied buffer. N bytes of data are copied into buffer Z
+** from the open BLOB, starting at offset iOffset.)^
+**
+** ^If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
+** less than zero, [SQLITE_ERROR] is returned and no data is read.
+** ^The size of the blob (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
+**
+** ^An attempt to read from an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].
+**
+** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
+** Otherwise, an [error code] or an [extended error code] is returned.)^
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()]. Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+**
+** See also: [sqlite3_blob_write()].
+*/
+SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
+
+/*
+** CAPI3REF: Write Data Into A BLOB Incrementally
+** METHOD: sqlite3_blob
+**
+** ^(This function is used to write data into an open [BLOB handle] from a
+** caller-supplied buffer. N bytes of data are copied from the buffer Z
+** into the open BLOB, starting at offset iOffset.)^
+**
+** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
+** Otherwise, an [error code] or an [extended error code] is returned.)^
+** ^Unless SQLITE_MISUSE is returned, this function sets the
+** [database connection] error code and message accessible via
+** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
+**
+** ^If the [BLOB handle] passed as the first argument was not opened for
+** writing (the flags parameter to [sqlite3_blob_open()] was zero),
+** this function returns [SQLITE_READONLY].
+**
+** This function may only modify the contents of the BLOB; it is
+** not possible to increase the size of a BLOB using this API.
+** ^If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is written. The size of the
+** BLOB (and hence the maximum value of N+iOffset) can be determined
+** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
+** than zero [SQLITE_ERROR] is returned and no data is written.
+**
+** ^An attempt to write to an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
+** before the [BLOB handle] expired are not rolled back by the
+** expiration of the handle, though of course those changes might
+** have been overwritten by the statement that expired the BLOB handle
+** or by other independent statements.
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()]. Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+**
+** See also: [sqlite3_blob_read()].
+*/
+SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
+
+/*
+** CAPI3REF: Virtual File System Objects
+**
+** A virtual filesystem (VFS) is an [sqlite3_vfs] object
+** that SQLite uses to interact
+** with the underlying operating system. Most SQLite builds come with a
+** single default VFS that is appropriate for the host computer.
+** New VFSes can be registered and existing VFSes can be unregistered.
+** The following interfaces are provided.
+**
+** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
+** ^Names are case sensitive.
+** ^Names are zero-terminated UTF-8 strings.
+** ^If there is no match, a NULL pointer is returned.
+** ^If zVfsName is NULL then the default VFS is returned.
+**
+** ^New VFSes are registered with sqlite3_vfs_register().
+** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
+** ^The same VFS can be registered multiple times without injury.
+** ^To make an existing VFS into the default VFS, register it again
+** with the makeDflt flag set. If two different VFSes with the
+** same name are registered, the behavior is undefined. If a
+** VFS is registered with a name that is NULL or an empty string,
+** then the behavior is undefined.
+**
+** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
+** ^(If the default VFS is unregistered, another VFS is chosen as
+** the default. The choice for the new VFS is arbitrary.)^
+*/
+SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
+SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
+SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
+
+/*
+** CAPI3REF: Mutexes
+**
+** The SQLite core uses these routines for thread
+** synchronization. Though they are intended for internal
+** use by SQLite, code that links against SQLite is
+** permitted to use any of these routines.
+**
+** The SQLite source code contains multiple implementations
+** of these mutex routines. An appropriate implementation
+** is selected automatically at compile-time. The following
+** implementations are available in the SQLite core:
+**
+**
+**
SQLITE_MUTEX_PTHREADS
+**
SQLITE_MUTEX_W32
+**
SQLITE_MUTEX_NOOP
+**
+**
+** The SQLITE_MUTEX_NOOP implementation is a set of routines
+** that does no real locking and is appropriate for use in
+** a single-threaded application. The SQLITE_MUTEX_PTHREADS and
+** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
+** and Windows.
+**
+** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
+** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
+** implementation is included with the library. In this case the
+** application must supply a custom mutex implementation using the
+** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
+** before calling sqlite3_initialize() or any other public sqlite3_
+** function that calls sqlite3_initialize().
+**
+** ^The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
+** routine returns NULL if it is unable to allocate the requested
+** mutex. The argument to sqlite3_mutex_alloc() must one of these
+** integer constants:
+**
+**
+**
SQLITE_MUTEX_FAST
+**
SQLITE_MUTEX_RECURSIVE
+**
SQLITE_MUTEX_STATIC_MASTER
+**
SQLITE_MUTEX_STATIC_MEM
+**
SQLITE_MUTEX_STATIC_OPEN
+**
SQLITE_MUTEX_STATIC_PRNG
+**
SQLITE_MUTEX_STATIC_LRU
+**
SQLITE_MUTEX_STATIC_PMEM
+**
SQLITE_MUTEX_STATIC_APP1
+**
SQLITE_MUTEX_STATIC_APP2
+**
SQLITE_MUTEX_STATIC_APP3
+**
SQLITE_MUTEX_STATIC_VFS1
+**
SQLITE_MUTEX_STATIC_VFS2
+**
SQLITE_MUTEX_STATIC_VFS3
+**
+**
+** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
+** cause sqlite3_mutex_alloc() to create
+** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
+** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
+** The mutex implementation does not need to make a distinction
+** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
+** not want to. SQLite will only request a recursive mutex in
+** cases where it really needs one. If a faster non-recursive mutex
+** implementation is available on the host platform, the mutex subsystem
+** might return such a mutex in response to SQLITE_MUTEX_FAST.
+**
+** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
+** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
+** a pointer to a static preexisting mutex. ^Nine static mutexes are
+** used by the current version of SQLite. Future versions of SQLite
+** may add additional static mutexes. Static mutexes are for internal
+** use by SQLite only. Applications that use SQLite mutexes should
+** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
+** SQLITE_MUTEX_RECURSIVE.
+**
+** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
+** returns a different mutex on every call. ^For the static
+** mutex types, the same mutex is returned on every call that has
+** the same type number.
+**
+** ^The sqlite3_mutex_free() routine deallocates a previously
+** allocated dynamic mutex. Attempting to deallocate a static
+** mutex results in undefined behavior.
+**
+** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex. ^If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
+** upon successful entry. ^(Mutexes created using
+** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
+** In such cases, the
+** mutex must be exited an equal number of times before another thread
+** can enter.)^ If the same thread tries to enter any mutex other
+** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
+**
+** ^(Some systems (for example, Windows 95) do not support the operation
+** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
+** will always return SQLITE_BUSY. The SQLite core only ever uses
+** sqlite3_mutex_try() as an optimization so this is acceptable
+** behavior.)^
+**
+** ^The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread. The behavior
+** is undefined if the mutex is not currently entered by the
+** calling thread or is not currently allocated.
+**
+** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
+** sqlite3_mutex_leave() is a NULL pointer, then all three routines
+** behave as no-ops.
+**
+** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
+*/
+SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
+SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
+SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
+SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
+
+/*
+** CAPI3REF: Mutex Methods Object
+**
+** An instance of this structure defines the low-level routines
+** used to allocate and use mutexes.
+**
+** Usually, the default mutex implementations provided by SQLite are
+** sufficient, however the application has the option of substituting a custom
+** implementation for specialized deployments or systems for which SQLite
+** does not provide a suitable implementation. In this case, the application
+** creates and populates an instance of this structure to pass
+** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
+** Additionally, an instance of this structure can be used as an
+** output variable when querying the system for the current mutex
+** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
+**
+** ^The xMutexInit method defined by this structure is invoked as
+** part of system initialization by the sqlite3_initialize() function.
+** ^The xMutexInit routine is called by SQLite exactly once for each
+** effective call to [sqlite3_initialize()].
+**
+** ^The xMutexEnd method defined by this structure is invoked as
+** part of system shutdown by the sqlite3_shutdown() function. The
+** implementation of this method is expected to release all outstanding
+** resources obtained by the mutex methods implementation, especially
+** those obtained by the xMutexInit method. ^The xMutexEnd()
+** interface is invoked exactly once for each call to [sqlite3_shutdown()].
+**
+** ^(The remaining seven methods defined by this structure (xMutexAlloc,
+** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
+** xMutexNotheld) implement the following interfaces (respectively):
+**
+**
+**
[sqlite3_mutex_alloc()]
+**
[sqlite3_mutex_free()]
+**
[sqlite3_mutex_enter()]
+**
[sqlite3_mutex_try()]
+**
[sqlite3_mutex_leave()]
+**
[sqlite3_mutex_held()]
+**
[sqlite3_mutex_notheld()]
+**
)^
+**
+** The only difference is that the public sqlite3_XXX functions enumerated
+** above silently ignore any invocations that pass a NULL pointer instead
+** of a valid mutex handle. The implementations of the methods defined
+** by this structure are not required to handle this case, the results
+** of passing a NULL pointer instead of a valid mutex handle are undefined
+** (i.e. it is acceptable to provide an implementation that segfaults if
+** it is passed a NULL pointer).
+**
+** The xMutexInit() method must be threadsafe. It must be harmless to
+** invoke xMutexInit() multiple times within the same process and without
+** intervening calls to xMutexEnd(). Second and subsequent calls to
+** xMutexInit() must be no-ops.
+**
+** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
+** and its associates). Similarly, xMutexAlloc() must not use SQLite memory
+** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
+** memory allocation for a fast or recursive mutex.
+**
+** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
+** called, but only if the prior call to xMutexInit returned SQLITE_OK.
+** If xMutexInit fails in any way, it is expected to clean up after itself
+** prior to returning.
+*/
+typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
+struct sqlite3_mutex_methods {
+ int (*xMutexInit)(void);
+ int (*xMutexEnd)(void);
+ sqlite3_mutex *(*xMutexAlloc)(int);
+ void (*xMutexFree)(sqlite3_mutex *);
+ void (*xMutexEnter)(sqlite3_mutex *);
+ int (*xMutexTry)(sqlite3_mutex *);
+ void (*xMutexLeave)(sqlite3_mutex *);
+ int (*xMutexHeld)(sqlite3_mutex *);
+ int (*xMutexNotheld)(sqlite3_mutex *);
+};
+
+/*
+** CAPI3REF: Mutex Verification Routines
+**
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
+** are intended for use inside assert() statements. The SQLite core
+** never uses these routines except inside an assert() and applications
+** are advised to follow the lead of the core. The SQLite core only
+** provides implementations for these routines when it is compiled
+** with the SQLITE_DEBUG flag. External mutex implementations
+** are only required to provide these routines if SQLITE_DEBUG is
+** defined and if NDEBUG is not defined.
+**
+** These routines should return true if the mutex in their argument
+** is held or not held, respectively, by the calling thread.
+**
+** The implementation is not required to provide versions of these
+** routines that actually work. If the implementation does not provide working
+** versions of these routines, it should at least provide stubs that always
+** return true so that one does not get spurious assertion failures.
+**
+** If the argument to sqlite3_mutex_held() is a NULL pointer then
+** the routine should return 1. This seems counter-intuitive since
+** clearly the mutex cannot be held if it does not exist. But
+** the reason the mutex does not exist is because the build is not
+** using mutexes. And we do not want the assert() containing the
+** call to sqlite3_mutex_held() to fail, so a non-zero return is
+** the appropriate thing to do. The sqlite3_mutex_notheld()
+** interface should also return 1 when given a NULL pointer.
+*/
+#ifndef NDEBUG
+SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
+#endif
+
+/*
+** CAPI3REF: Mutex Types
+**
+** The [sqlite3_mutex_alloc()] interface takes a single argument
+** which is one of these integer constants.
+**
+** The set of static mutexes may change from one SQLite release to the
+** next. Applications that override the built-in mutex logic must be
+** prepared to accommodate additional static mutexes.
+*/
+#define SQLITE_MUTEX_FAST 0
+#define SQLITE_MUTEX_RECURSIVE 1
+#define SQLITE_MUTEX_STATIC_MASTER 2
+#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
+#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
+#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
+#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */
+#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
+#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
+#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
+#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */
+#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */
+#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */
+#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */
+#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */
+#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */
+
+/*
+** CAPI3REF: Retrieve the mutex for a database connection
+** METHOD: sqlite3
+**
+** ^This interface returns a pointer the [sqlite3_mutex] object that
+** serializes access to the [database connection] given in the argument
+** when the [threading mode] is Serialized.
+** ^If the [threading mode] is Single-thread or Multi-thread then this
+** routine returns a NULL pointer.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
+
+/*
+** CAPI3REF: Low-Level Control Of Database Files
+** METHOD: sqlite3
+** KEYWORDS: {file control}
+**
+** ^The [sqlite3_file_control()] interface makes a direct call to the
+** xFileControl method for the [sqlite3_io_methods] object associated
+** with a particular database identified by the second argument. ^The
+** name of the database is "main" for the main database or "temp" for the
+** TEMP database, or the name that appears after the AS keyword for
+** databases that are added using the [ATTACH] SQL command.
+** ^A NULL pointer can be used in place of "main" to refer to the
+** main database file.
+** ^The third and fourth parameters to this routine
+** are passed directly through to the second and third parameters of
+** the xFileControl method. ^The return value of the xFileControl
+** method becomes the return value of this routine.
+**
+** A few opcodes for [sqlite3_file_control()] are handled directly
+** by the SQLite core and never invoke the
+** sqlite3_io_methods.xFileControl method.
+** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes
+** a pointer to the underlying [sqlite3_file] object to be written into
+** the space pointed to by the 4th parameter. The
+** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns
+** the [sqlite3_file] object associated with the journal file instead of
+** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns
+** a pointer to the underlying [sqlite3_vfs] object for the file.
+** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter
+** from the pager.
+**
+** ^If the second parameter (zDbName) does not match the name of any
+** open database file, then SQLITE_ERROR is returned. ^This error
+** code is not remembered and will not be recalled by [sqlite3_errcode()]
+** or [sqlite3_errmsg()]. The underlying xFileControl method might
+** also return SQLITE_ERROR. There is no way to distinguish between
+** an incorrect zDbName and an SQLITE_ERROR return from the underlying
+** xFileControl method.
+**
+** See also: [file control opcodes]
+*/
+SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
+
+/*
+** CAPI3REF: Testing Interface
+**
+** ^The sqlite3_test_control() interface is used to read out internal
+** state of SQLite and to inject faults into SQLite for testing
+** purposes. ^The first parameter is an operation code that determines
+** the number, meaning, and operation of all subsequent parameters.
+**
+** This interface is not for use by applications. It exists solely
+** for verifying the correct operation of the SQLite library. Depending
+** on how the SQLite library is compiled, this interface might not exist.
+**
+** The details of the operation codes, their meanings, the parameters
+** they take, and what they do are all subject to change without notice.
+** Unlike most of the SQLite API, this function is not guaranteed to
+** operate consistently from one release to the next.
+*/
+SQLITE_API int sqlite3_test_control(int op, ...);
+
+/*
+** CAPI3REF: Testing Interface Operation Codes
+**
+** These constants are the valid operation code parameters used
+** as the first argument to [sqlite3_test_control()].
+**
+** These parameters and their meanings are subject to change
+** without notice. These values are for testing purposes only.
+** Applications should not use any of these parameters or the
+** [sqlite3_test_control()] interface.
+*/
+#define SQLITE_TESTCTRL_FIRST 5
+#define SQLITE_TESTCTRL_PRNG_SAVE 5
+#define SQLITE_TESTCTRL_PRNG_RESTORE 6
+#define SQLITE_TESTCTRL_PRNG_RESET 7
+#define SQLITE_TESTCTRL_BITVEC_TEST 8
+#define SQLITE_TESTCTRL_FAULT_INSTALL 9
+#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
+#define SQLITE_TESTCTRL_PENDING_BYTE 11
+#define SQLITE_TESTCTRL_ASSERT 12
+#define SQLITE_TESTCTRL_ALWAYS 13
+#define SQLITE_TESTCTRL_RESERVE 14
+#define SQLITE_TESTCTRL_OPTIMIZATIONS 15
+#define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */
+#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */
+#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
+#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */
+#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19
+#define SQLITE_TESTCTRL_NEVER_CORRUPT 20
+#define SQLITE_TESTCTRL_VDBE_COVERAGE 21
+#define SQLITE_TESTCTRL_BYTEORDER 22
+#define SQLITE_TESTCTRL_ISINIT 23
+#define SQLITE_TESTCTRL_SORTER_MMAP 24
+#define SQLITE_TESTCTRL_IMPOSTER 25
+#define SQLITE_TESTCTRL_PARSER_COVERAGE 26
+#define SQLITE_TESTCTRL_LAST 26 /* Largest TESTCTRL */
+
+/*
+** CAPI3REF: SQL Keyword Checking
+**
+** These routines provide access to the set of SQL language keywords
+** recognized by SQLite. Applications can uses these routines to determine
+** whether or not a specific identifier needs to be escaped (for example,
+** by enclosing in double-quotes) so as not to confuse the parser.
+**
+** The sqlite3_keyword_count() interface returns the number of distinct
+** keywords understood by SQLite.
+**
+** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and
+** makes *Z point to that keyword expressed as UTF8 and writes the number
+** of bytes in the keyword into *L. The string that *Z points to is not
+** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns
+** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
+** or L are NULL or invalid pointers then calls to
+** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
+**
+** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
+** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
+** if it is and zero if not.
+**
+** The parser used by SQLite is forgiving. It is often possible to use
+** a keyword as an identifier as long as such use does not result in a
+** parsing ambiguity. For example, the statement
+** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
+** creates a new table named "BEGIN" with three columns named
+** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid
+** using keywords as identifiers. Common techniques used to avoid keyword
+** name collisions include:
+**
+**
Put all identifier names inside double-quotes. This is the official
+** SQL way to escape identifier names.
+**
Put identifier names inside [...]. This is not standard SQL,
+** but it is what SQL Server does and so lots of programmers use this
+** technique.
+**
Begin every identifier with the letter "Z" as no SQL keywords start
+** with "Z".
+**
Include a digit somewhere in every identifier name.
+**
+**
+** Note that the number of keywords understood by SQLite can depend on
+** compile-time options. For example, "VACUUM" is not a keyword if
+** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also,
+** new keywords may be added to future releases of SQLite.
+*/
+SQLITE_API int sqlite3_keyword_count(void);
+SQLITE_API int sqlite3_keyword_name(int,const char**,int*);
+SQLITE_API int sqlite3_keyword_check(const char*,int);
+
+/*
+** CAPI3REF: Dynamic String Object
+** KEYWORDS: {dynamic string}
+**
+** An instance of the sqlite3_str object contains a dynamically-sized
+** string under construction.
+**
+** The lifecycle of an sqlite3_str object is as follows:
+**
+**
^The sqlite3_str object is created using [sqlite3_str_new()].
+**
^Text is appended to the sqlite3_str object using various
+** methods, such as [sqlite3_str_appendf()].
+**
^The sqlite3_str object is destroyed and the string it created
+** is returned using the [sqlite3_str_finish()] interface.
+**
+*/
+typedef struct sqlite3_str sqlite3_str;
+
+/*
+** CAPI3REF: Create A New Dynamic String Object
+** CONSTRUCTOR: sqlite3_str
+**
+** ^The [sqlite3_str_new(D)] interface allocates and initializes
+** a new [sqlite3_str] object. To avoid memory leaks, the object returned by
+** [sqlite3_str_new()] must be freed by a subsequent call to
+** [sqlite3_str_finish(X)].
+**
+** ^The [sqlite3_str_new(D)] interface always returns a pointer to a
+** valid [sqlite3_str] object, though in the event of an out-of-memory
+** error the returned object might be a special singleton that will
+** silently reject new text, always return SQLITE_NOMEM from
+** [sqlite3_str_errcode()], always return 0 for
+** [sqlite3_str_length()], and always return NULL from
+** [sqlite3_str_finish(X)]. It is always safe to use the value
+** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter
+** to any of the other [sqlite3_str] methods.
+**
+** The D parameter to [sqlite3_str_new(D)] may be NULL. If the
+** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum
+** length of the string contained in the [sqlite3_str] object will be
+** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead
+** of [SQLITE_MAX_LENGTH].
+*/
+SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*);
+
+/*
+** CAPI3REF: Finalize A Dynamic String
+** DESTRUCTOR: sqlite3_str
+**
+** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X
+** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()]
+** that contains the constructed string. The calling application should
+** pass the returned value to [sqlite3_free()] to avoid a memory leak.
+** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any
+** errors were encountered during construction of the string. ^The
+** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the
+** string in [sqlite3_str] object X is zero bytes long.
+*/
+SQLITE_API char *sqlite3_str_finish(sqlite3_str*);
+
+/*
+** CAPI3REF: Add Content To A Dynamic String
+** METHOD: sqlite3_str
+**
+** These interfaces add content to an sqlite3_str object previously obtained
+** from [sqlite3_str_new()].
+**
+** ^The [sqlite3_str_appendf(X,F,...)] and
+** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf]
+** functionality of SQLite to append formatted text onto the end of
+** [sqlite3_str] object X.
+**
+** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S
+** onto the end of the [sqlite3_str] object X. N must be non-negative.
+** S must contain at least N non-zero bytes of content. To append a
+** zero-terminated string in its entirety, use the [sqlite3_str_appendall()]
+** method instead.
+**
+** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of
+** zero-terminated string S onto the end of [sqlite3_str] object X.
+**
+** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the
+** single-byte character C onto the end of [sqlite3_str] object X.
+** ^This method can be used, for example, to add whitespace indentation.
+**
+** ^The [sqlite3_str_reset(X)] method resets the string under construction
+** inside [sqlite3_str] object X back to zero bytes in length.
+**
+** These methods do not return a result code. ^If an error occurs, that fact
+** is recorded in the [sqlite3_str] object and can be recovered by a
+** subsequent call to [sqlite3_str_errcode(X)].
+*/
+SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...);
+SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list);
+SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N);
+SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn);
+SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C);
+SQLITE_API void sqlite3_str_reset(sqlite3_str*);
+
+/*
+** CAPI3REF: Status Of A Dynamic String
+** METHOD: sqlite3_str
+**
+** These interfaces return the current status of an [sqlite3_str] object.
+**
+** ^If any prior errors have occurred while constructing the dynamic string
+** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return
+** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns
+** [SQLITE_NOMEM] following any out-of-memory error, or
+** [SQLITE_TOOBIG] if the size of the dynamic string exceeds
+** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors.
+**
+** ^The [sqlite3_str_length(X)] method returns the current length, in bytes,
+** of the dynamic string under construction in [sqlite3_str] object X.
+** ^The length returned by [sqlite3_str_length(X)] does not include the
+** zero-termination byte.
+**
+** ^The [sqlite3_str_value(X)] method returns a pointer to the current
+** content of the dynamic string under construction in X. The value
+** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X
+** and might be freed or altered by any subsequent method on the same
+** [sqlite3_str] object. Applications must not used the pointer returned
+** [sqlite3_str_value(X)] after any subsequent method call on the same
+** object. ^Applications may change the content of the string returned
+** by [sqlite3_str_value(X)] as long as they do not write into any bytes
+** outside the range of 0 to [sqlite3_str_length(X)] and do not read or
+** write any byte after any subsequent sqlite3_str method call.
+*/
+SQLITE_API int sqlite3_str_errcode(sqlite3_str*);
+SQLITE_API int sqlite3_str_length(sqlite3_str*);
+SQLITE_API char *sqlite3_str_value(sqlite3_str*);
+
+/*
+** CAPI3REF: SQLite Runtime Status
+**
+** ^These interfaces are used to retrieve runtime status information
+** about the performance of SQLite, and optionally to reset various
+** highwater marks. ^The first argument is an integer code for
+** the specific parameter to measure. ^(Recognized integer codes
+** are of the form [status parameters | SQLITE_STATUS_...].)^
+** ^The current value of the parameter is returned into *pCurrent.
+** ^The highest recorded value is returned in *pHighwater. ^If the
+** resetFlag is true, then the highest record value is reset after
+** *pHighwater is written. ^(Some parameters do not record the highest
+** value. For those parameters
+** nothing is written into *pHighwater and the resetFlag is ignored.)^
+** ^(Other parameters record only the highwater mark and not the current
+** value. For these latter parameters nothing is written into *pCurrent.)^
+**
+** ^The sqlite3_status() and sqlite3_status64() routines return
+** SQLITE_OK on success and a non-zero [error code] on failure.
+**
+** If either the current value or the highwater mark is too large to
+** be represented by a 32-bit integer, then the values returned by
+** sqlite3_status() are undefined.
+**
+** See also: [sqlite3_db_status()]
+*/
+SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
+SQLITE_API int sqlite3_status64(
+ int op,
+ sqlite3_int64 *pCurrent,
+ sqlite3_int64 *pHighwater,
+ int resetFlag
+);
+
+
+/*
+** CAPI3REF: Status Parameters
+** KEYWORDS: {status parameters}
+**
+** These integer constants designate various run-time status parameters
+** that can be returned by [sqlite3_status()].
+**
+**
+** [[SQLITE_STATUS_MEMORY_USED]] ^(
SQLITE_STATUS_MEMORY_USED
+**
This parameter is the current amount of memory checked out
+** using [sqlite3_malloc()], either directly or indirectly. The
+** figure includes calls made to [sqlite3_malloc()] by the application
+** and internal memory usage by the SQLite library. Auxiliary page-cache
+** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
+** this parameter. The amount returned is the sum of the allocation
+** sizes as reported by the xSize method in [sqlite3_mem_methods].
)^
+**
+** [[SQLITE_STATUS_MALLOC_SIZE]] ^(
SQLITE_STATUS_MALLOC_SIZE
+**
This parameter records the largest memory allocation request
+** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
+** internal equivalents). Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.
+** The value written into the *pCurrent parameter is undefined.
)^
+**
+** [[SQLITE_STATUS_MALLOC_COUNT]] ^(
SQLITE_STATUS_MALLOC_COUNT
+**
This parameter records the number of separate memory allocations
+** currently checked out.
)^
+**
+** [[SQLITE_STATUS_PAGECACHE_USED]] ^(
SQLITE_STATUS_PAGECACHE_USED
+**
This parameter returns the number of pages used out of the
+** [pagecache memory allocator] that was configured using
+** [SQLITE_CONFIG_PAGECACHE]. The
+** value returned is in pages, not in bytes.
This parameter returns the number of bytes of page cache
+** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
+** buffer and where forced to overflow to [sqlite3_malloc()]. The
+** returned value includes allocations that overflowed because they
+** where too large (they were larger than the "sz" parameter to
+** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
+** no space was left in the page cache.
)^
+**
+** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(
SQLITE_STATUS_PAGECACHE_SIZE
+**
This parameter records the largest memory allocation request
+** handed to [pagecache memory allocator]. Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.
+** The value written into the *pCurrent parameter is undefined.
)^
+**
+** [[SQLITE_STATUS_SCRATCH_USED]]
SQLITE_STATUS_SCRATCH_USED
+**
No longer used.
+**
+** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(
SQLITE_STATUS_SCRATCH_OVERFLOW
+**
No longer used.
+**
+** [[SQLITE_STATUS_SCRATCH_SIZE]]
SQLITE_STATUS_SCRATCH_SIZE
+**
No longer used.
+**
+** [[SQLITE_STATUS_PARSER_STACK]] ^(
SQLITE_STATUS_PARSER_STACK
+**
The *pHighwater parameter records the deepest parser stack.
+** The *pCurrent value is undefined. The *pHighwater value is only
+** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].
)^
+**
+**
+** New status parameters may be added from time to time.
+*/
+#define SQLITE_STATUS_MEMORY_USED 0
+#define SQLITE_STATUS_PAGECACHE_USED 1
+#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
+#define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */
+#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */
+#define SQLITE_STATUS_MALLOC_SIZE 5
+#define SQLITE_STATUS_PARSER_STACK 6
+#define SQLITE_STATUS_PAGECACHE_SIZE 7
+#define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */
+#define SQLITE_STATUS_MALLOC_COUNT 9
+
+/*
+** CAPI3REF: Database Connection Status
+** METHOD: sqlite3
+**
+** ^This interface is used to retrieve runtime status information
+** about a single [database connection]. ^The first argument is the
+** database connection object to be interrogated. ^The second argument
+** is an integer constant, taken from the set of
+** [SQLITE_DBSTATUS options], that
+** determines the parameter to interrogate. The set of
+** [SQLITE_DBSTATUS options] is likely
+** to grow in future releases of SQLite.
+**
+** ^The current value of the requested parameter is written into *pCur
+** and the highest instantaneous value is written into *pHiwtr. ^If
+** the resetFlg is true, then the highest instantaneous value is
+** reset back down to the current value.
+**
+** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** non-zero [error code] on failure.
+**
+** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
+*/
+SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for database connections
+** KEYWORDS: {SQLITE_DBSTATUS options}
+**
+** These constants are the available integer "verbs" that can be passed as
+** the second argument to the [sqlite3_db_status()] interface.
+**
+** New verbs may be added in future releases of SQLite. Existing verbs
+** might be discontinued. Applications should check the return code from
+** [sqlite3_db_status()] to make sure that the call worked.
+** The [sqlite3_db_status()] interface will return a non-zero error code
+** if a discontinued or unsupported verb is invoked.
+**
+**
+** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(
SQLITE_DBSTATUS_LOOKASIDE_USED
+**
This parameter returns the number of lookaside memory slots currently
+** checked out.
)^
+**
+** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(
SQLITE_DBSTATUS_LOOKASIDE_HIT
+**
This parameter returns the number malloc attempts that were
+** satisfied using lookaside memory. Only the high-water value is meaningful;
+** the current value is always zero.)^
+**
+** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
+** ^(
SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE
+**
This parameter returns the number malloc attempts that might have
+** been satisfied using lookaside memory but failed due to the amount of
+** memory requested being larger than the lookaside slot size.
+** Only the high-water value is meaningful;
+** the current value is always zero.)^
+**
+** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
+** ^(
SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL
+**
This parameter returns the number malloc attempts that might have
+** been satisfied using lookaside memory but failed due to all lookaside
+** memory already being in use.
+** Only the high-water value is meaningful;
+** the current value is always zero.)^
+**
+** [[SQLITE_DBSTATUS_CACHE_USED]] ^(
SQLITE_DBSTATUS_CACHE_USED
+**
This parameter returns the approximate number of bytes of heap
+** memory used by all pager caches associated with the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
+**
+** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
+** ^(
SQLITE_DBSTATUS_CACHE_USED_SHARED
+**
This parameter is similar to DBSTATUS_CACHE_USED, except that if a
+** pager cache is shared between two or more connections the bytes of heap
+** memory used by that pager cache is divided evenly between the attached
+** connections.)^ In other words, if none of the pager caches associated
+** with the database connection are shared, this request returns the same
+** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are
+** shared, the value returned by this call will be smaller than that returned
+** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
+** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
+**
+** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(
SQLITE_DBSTATUS_SCHEMA_USED
+**
This parameter returns the approximate number of bytes of heap
+** memory used to store the schema for all databases associated
+** with the connection - main, temp, and any [ATTACH]-ed databases.)^
+** ^The full amount of memory used by the schemas is reported, even if the
+** schema memory is shared with other database connections due to
+** [shared cache mode] being enabled.
+** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
+**
+** [[SQLITE_DBSTATUS_STMT_USED]] ^(
SQLITE_DBSTATUS_STMT_USED
+**
This parameter returns the approximate number of bytes of heap
+** and lookaside memory used by all prepared statements associated with
+** the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
+**
+**
+** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(
SQLITE_DBSTATUS_CACHE_HIT
+**
This parameter returns the number of pager cache hits that have
+** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
+** is always 0.
+**
+**
+** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(
SQLITE_DBSTATUS_CACHE_MISS
+**
This parameter returns the number of pager cache misses that have
+** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
+** is always 0.
+**
+**
+** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(
SQLITE_DBSTATUS_CACHE_WRITE
+**
This parameter returns the number of dirty cache entries that have
+** been written to disk. Specifically, the number of pages written to the
+** wal file in wal mode databases, or the number of pages written to the
+** database file in rollback mode databases. Any pages written as part of
+** transaction rollback or database recovery operations are not included.
+** If an IO or other error occurs while writing a page to disk, the effect
+** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
+** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
+**
+**
+** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(
SQLITE_DBSTATUS_CACHE_SPILL
+**
This parameter returns the number of dirty cache entries that have
+** been written to disk in the middle of a transaction due to the page
+** cache overflowing. Transactions are more efficient if they are written
+** to disk all at once. When pages spill mid-transaction, that introduces
+** additional overhead. This parameter can be used help identify
+** inefficiencies that can be resolve by increasing the cache size.
+**
+**
+** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(
SQLITE_DBSTATUS_DEFERRED_FKS
+**
This parameter returns zero for the current value if and only if
+** all foreign key constraints (deferred or immediate) have been
+** resolved.)^ ^The highwater mark is always 0.
+**
+**
+*/
+#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
+#define SQLITE_DBSTATUS_CACHE_USED 1
+#define SQLITE_DBSTATUS_SCHEMA_USED 2
+#define SQLITE_DBSTATUS_STMT_USED 3
+#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
+#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
+#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
+#define SQLITE_DBSTATUS_CACHE_HIT 7
+#define SQLITE_DBSTATUS_CACHE_MISS 8
+#define SQLITE_DBSTATUS_CACHE_WRITE 9
+#define SQLITE_DBSTATUS_DEFERRED_FKS 10
+#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11
+#define SQLITE_DBSTATUS_CACHE_SPILL 12
+#define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */
+
+
+/*
+** CAPI3REF: Prepared Statement Status
+** METHOD: sqlite3_stmt
+**
+** ^(Each prepared statement maintains various
+** [SQLITE_STMTSTATUS counters] that measure the number
+** of times it has performed specific operations.)^ These counters can
+** be used to monitor the performance characteristics of the prepared
+** statements. For example, if the number of table steps greatly exceeds
+** the number of table searches or result rows, that would tend to indicate
+** that the prepared statement is using a full table scan rather than
+** an index.
+**
+** ^(This interface is used to retrieve and reset counter values from
+** a [prepared statement]. The first argument is the prepared statement
+** object to be interrogated. The second argument
+** is an integer code for a specific [SQLITE_STMTSTATUS counter]
+** to be interrogated.)^
+** ^The current value of the requested counter is returned.
+** ^If the resetFlg is true, then the counter is reset to zero after this
+** interface call returns.
+**
+** See also: [sqlite3_status()] and [sqlite3_db_status()].
+*/
+SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for prepared statements
+** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
+**
+** These preprocessor macros define integer codes that name counter
+** values associated with the [sqlite3_stmt_status()] interface.
+** The meanings of the various counters are as follows:
+**
+**
+** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]]
SQLITE_STMTSTATUS_FULLSCAN_STEP
+**
^This is the number of times that SQLite has stepped forward in
+** a table as part of a full table scan. Large numbers for this counter
+** may indicate opportunities for performance improvement through
+** careful use of indices.
+**
+** [[SQLITE_STMTSTATUS_SORT]]
SQLITE_STMTSTATUS_SORT
+**
^This is the number of sort operations that have occurred.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance through careful use of indices.
+**
+** [[SQLITE_STMTSTATUS_AUTOINDEX]]
SQLITE_STMTSTATUS_AUTOINDEX
+**
^This is the number of rows inserted into transient indices that
+** were created automatically in order to help joins run faster.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance by adding permanent indices that do not
+** need to be reinitialized each time the statement is run.
+**
+** [[SQLITE_STMTSTATUS_VM_STEP]]
SQLITE_STMTSTATUS_VM_STEP
+**
^This is the number of virtual machine operations executed
+** by the prepared statement if that number is less than or equal
+** to 2147483647. The number of virtual machine operations can be
+** used as a proxy for the total work done by the prepared statement.
+** If the number of virtual machine operations exceeds 2147483647
+** then the value returned by this statement status code is undefined.
+**
+** [[SQLITE_STMTSTATUS_REPREPARE]]
SQLITE_STMTSTATUS_REPREPARE
+**
^This is the number of times that the prepare statement has been
+** automatically regenerated due to schema changes or change to
+** [bound parameters] that might affect the query plan.
+**
+** [[SQLITE_STMTSTATUS_RUN]]
SQLITE_STMTSTATUS_RUN
+**
^This is the number of times that the prepared statement has
+** been run. A single "run" for the purposes of this counter is one
+** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
+** The counter is incremented on the first [sqlite3_step()] call of each
+** cycle.
+**
+** [[SQLITE_STMTSTATUS_MEMUSED]]
SQLITE_STMTSTATUS_MEMUSED
+**
^This is the approximate number of bytes of heap memory
+** used to store the prepared statement. ^This value is not actually
+** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
+** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
+**
+**
+*/
+#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
+#define SQLITE_STMTSTATUS_SORT 2
+#define SQLITE_STMTSTATUS_AUTOINDEX 3
+#define SQLITE_STMTSTATUS_VM_STEP 4
+#define SQLITE_STMTSTATUS_REPREPARE 5
+#define SQLITE_STMTSTATUS_RUN 6
+#define SQLITE_STMTSTATUS_MEMUSED 99
+
+/*
+** CAPI3REF: Custom Page Cache Object
+**
+** The sqlite3_pcache type is opaque. It is implemented by
+** the pluggable module. The SQLite core has no knowledge of
+** its size or internal structure and never deals with the
+** sqlite3_pcache object except by holding and passing pointers
+** to the object.
+**
+** See [sqlite3_pcache_methods2] for additional information.
+*/
+typedef struct sqlite3_pcache sqlite3_pcache;
+
+/*
+** CAPI3REF: Custom Page Cache Object
+**
+** The sqlite3_pcache_page object represents a single page in the
+** page cache. The page cache will allocate instances of this
+** object. Various methods of the page cache use pointers to instances
+** of this object as parameters or as their return value.
+**
+** See [sqlite3_pcache_methods2] for additional information.
+*/
+typedef struct sqlite3_pcache_page sqlite3_pcache_page;
+struct sqlite3_pcache_page {
+ void *pBuf; /* The content of the page */
+ void *pExtra; /* Extra information associated with the page */
+};
+
+/*
+** CAPI3REF: Application Defined Page Cache.
+** KEYWORDS: {page cache}
+**
+** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
+** register an alternative page cache implementation by passing in an
+** instance of the sqlite3_pcache_methods2 structure.)^
+** In many applications, most of the heap memory allocated by
+** SQLite is used for the page cache.
+** By implementing a
+** custom page cache using this API, an application can better control
+** the amount of memory consumed by SQLite, the way in which
+** that memory is allocated and released, and the policies used to
+** determine exactly which parts of a database file are cached and for
+** how long.
+**
+** The alternative page cache mechanism is an
+** extreme measure that is only needed by the most demanding applications.
+** The built-in page cache is recommended for most uses.
+**
+** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
+** internal buffer by SQLite within the call to [sqlite3_config]. Hence
+** the application may discard the parameter after the call to
+** [sqlite3_config()] returns.)^
+**
+** [[the xInit() page cache method]]
+** ^(The xInit() method is called once for each effective
+** call to [sqlite3_initialize()])^
+** (usually only once during the lifetime of the process). ^(The xInit()
+** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
+** The intent of the xInit() method is to set up global data structures
+** required by the custom page cache implementation.
+** ^(If the xInit() method is NULL, then the
+** built-in default page cache is used instead of the application defined
+** page cache.)^
+**
+** [[the xShutdown() page cache method]]
+** ^The xShutdown() method is called by [sqlite3_shutdown()].
+** It can be used to clean up
+** any outstanding resources before process shutdown, if required.
+** ^The xShutdown() method may be NULL.
+**
+** ^SQLite automatically serializes calls to the xInit method,
+** so the xInit method need not be threadsafe. ^The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either. All other methods must be threadsafe
+** in multithreaded applications.
+**
+** ^SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+**
+** [[the xCreate() page cache methods]]
+** ^SQLite invokes the xCreate() method to construct a new cache instance.
+** SQLite will typically create one cache instance for each open database file,
+** though this is not guaranteed. ^The
+** first parameter, szPage, is the size in bytes of the pages that must
+** be allocated by the cache. ^szPage will always a power of two. ^The
+** second parameter szExtra is a number of bytes of extra storage
+** associated with each page cache entry. ^The szExtra parameter will
+** a number less than 250. SQLite will use the
+** extra szExtra bytes on each page to store metadata about the underlying
+** database page on disk. The value passed into szExtra depends
+** on the SQLite version, the target platform, and how SQLite was compiled.
+** ^The third argument to xCreate(), bPurgeable, is true if the cache being
+** created will be used to cache database pages of a file stored on disk, or
+** false if it is used for an in-memory database. The cache implementation
+** does not have to do anything special based with the value of bPurgeable;
+** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
+** never invoke xUnpin() except to deliberately delete a page.
+** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
+** false will always have the "discard" flag set to true.
+** ^Hence, a cache created with bPurgeable false will
+** never contain any unpinned pages.
+**
+** [[the xCachesize() page cache method]]
+** ^(The xCachesize() method may be called at any time by SQLite to set the
+** suggested maximum cache-size (number of pages stored by) the cache
+** instance passed as the first argument. This is the value configured using
+** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
+** parameter, the implementation is not required to do anything with this
+** value; it is advisory only.
+**
+** [[the xPagecount() page cache methods]]
+** The xPagecount() method must return the number of pages currently
+** stored in the cache, both pinned and unpinned.
+**
+** [[the xFetch() page cache methods]]
+** The xFetch() method locates a page in the cache and returns a pointer to
+** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
+** The pBuf element of the returned sqlite3_pcache_page object will be a
+** pointer to a buffer of szPage bytes used to store the content of a
+** single database page. The pExtra element of sqlite3_pcache_page will be
+** a pointer to the szExtra bytes of extra storage that SQLite has requested
+** for each entry in the page cache.
+**
+** The page to be fetched is determined by the key. ^The minimum key value
+** is 1. After it has been retrieved using xFetch, the page is considered
+** to be "pinned".
+**
+** If the requested page is already in the page cache, then the page cache
+** implementation must return a pointer to the page buffer with its content
+** intact. If the requested page is not already in the cache, then the
+** cache implementation should use the value of the createFlag
+** parameter to help it determined what action to take:
+**
+**
+**
createFlag
Behavior when page is not already in cache
+**
0
Do not allocate a new page. Return NULL.
+**
1
Allocate a new page if it easy and convenient to do so.
+** Otherwise return NULL.
+**
2
Make every effort to allocate a new page. Only return
+** NULL if allocating a new page is effectively impossible.
+**
+**
+** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
+** will only use a createFlag of 2 after a prior call with a createFlag of 1
+** failed.)^ In between the to xFetch() calls, SQLite may
+** attempt to unpin one or more cache pages by spilling the content of
+** pinned pages to disk and synching the operating system disk cache.
+**
+** [[the xUnpin() page cache method]]
+** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
+** as its second argument. If the third parameter, discard, is non-zero,
+** then the page must be evicted from the cache.
+** ^If the discard parameter is
+** zero, then the page may be discarded or retained at the discretion of
+** page cache implementation. ^The page cache implementation
+** may choose to evict unpinned pages at any time.
+**
+** The cache must not perform any reference counting. A single
+** call to xUnpin() unpins the page regardless of the number of prior calls
+** to xFetch().
+**
+** [[the xRekey() page cache methods]]
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument. If the cache
+** previously contains an entry associated with newKey, it must be
+** discarded. ^Any prior cache entry associated with newKey is guaranteed not
+** to be pinned.
+**
+** When SQLite calls the xTruncate() method, the cache must discard all
+** existing cache entries with page numbers (keys) greater than or equal
+** to the value of the iLimit parameter passed to xTruncate(). If any
+** of these pages are pinned, they are implicitly unpinned, meaning that
+** they can be safely discarded.
+**
+** [[the xDestroy() page cache method]]
+** ^The xDestroy() method is used to delete a cache allocated by xCreate().
+** All resources associated with the specified cache should be freed. ^After
+** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
+** handle invalid, and will not use it with any other sqlite3_pcache_methods2
+** functions.
+**
+** [[the xShrink() page cache method]]
+** ^SQLite invokes the xShrink() method when it wants the page cache to
+** free up as much of heap memory as possible. The page cache implementation
+** is not obligated to free any memory, but well-behaved implementations should
+** do their best.
+*/
+typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
+struct sqlite3_pcache_methods2 {
+ int iVersion;
+ void *pArg;
+ int (*xInit)(void*);
+ void (*xShutdown)(void*);
+ sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
+ void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+ int (*xPagecount)(sqlite3_pcache*);
+ sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+ void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
+ void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
+ unsigned oldKey, unsigned newKey);
+ void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+ void (*xDestroy)(sqlite3_pcache*);
+ void (*xShrink)(sqlite3_pcache*);
+};
+
+/*
+** This is the obsolete pcache_methods object that has now been replaced
+** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
+** retained in the header file for backwards compatibility only.
+*/
+typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
+struct sqlite3_pcache_methods {
+ void *pArg;
+ int (*xInit)(void*);
+ void (*xShutdown)(void*);
+ sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
+ void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+ int (*xPagecount)(sqlite3_pcache*);
+ void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+ void (*xUnpin)(sqlite3_pcache*, void*, int discard);
+ void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
+ void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+ void (*xDestroy)(sqlite3_pcache*);
+};
+
+
+/*
+** CAPI3REF: Online Backup Object
+**
+** The sqlite3_backup object records state information about an ongoing
+** online backup operation. ^The sqlite3_backup object is created by
+** a call to [sqlite3_backup_init()] and is destroyed by a call to
+** [sqlite3_backup_finish()].
+**
+** See Also: [Using the SQLite Online Backup API]
+*/
+typedef struct sqlite3_backup sqlite3_backup;
+
+/*
+** CAPI3REF: Online Backup API.
+**
+** The backup API copies the content of one database into another.
+** It is useful either for creating backups of databases or
+** for copying in-memory databases to or from persistent files.
+**
+** See Also: [Using the SQLite Online Backup API]
+**
+** ^SQLite holds a write transaction open on the destination database file
+** for the duration of the backup operation.
+** ^The source database is read-locked only while it is being read;
+** it is not locked continuously for the entire backup operation.
+** ^Thus, the backup may be performed on a live source database without
+** preventing other database connections from
+** reading or writing to the source database while the backup is underway.
+**
+** ^(To perform a backup operation:
+**
+**
sqlite3_backup_init() is called once to initialize the
+** backup,
+**
sqlite3_backup_step() is called one or more times to transfer
+** the data between the two databases, and finally
+**
sqlite3_backup_finish() is called to release all resources
+** associated with the backup operation.
+**
)^
+** There should be exactly one call to sqlite3_backup_finish() for each
+** successful call to sqlite3_backup_init().
+**
+** [[sqlite3_backup_init()]] sqlite3_backup_init()
+**
+** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
+** [database connection] associated with the destination database
+** and the database name, respectively.
+** ^The database name is "main" for the main database, "temp" for the
+** temporary database, or the name specified after the AS keyword in
+** an [ATTACH] statement for an attached database.
+** ^The S and M arguments passed to
+** sqlite3_backup_init(D,N,S,M) identify the [database connection]
+** and database name of the source database, respectively.
+** ^The source and destination [database connections] (parameters S and D)
+** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
+** an error.
+**
+** ^A call to sqlite3_backup_init() will fail, returning NULL, if
+** there is already a read or read-write transaction open on the
+** destination database.
+**
+** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
+** returned and an error code and error message are stored in the
+** destination [database connection] D.
+** ^The error code and message for the failed call to sqlite3_backup_init()
+** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
+** [sqlite3_errmsg16()] functions.
+** ^A successful call to sqlite3_backup_init() returns a pointer to an
+** [sqlite3_backup] object.
+** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
+** sqlite3_backup_finish() functions to perform the specified backup
+** operation.
+**
+** [[sqlite3_backup_step()]] sqlite3_backup_step()
+**
+** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
+** the source and destination databases specified by [sqlite3_backup] object B.
+** ^If N is negative, all remaining source pages are copied.
+** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
+** are still more pages to be copied, then the function returns [SQLITE_OK].
+** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
+** from source to destination, then it returns [SQLITE_DONE].
+** ^If an error occurs while running sqlite3_backup_step(B,N),
+** then an [error code] is returned. ^As well as [SQLITE_OK] and
+** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
+** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
+**
+** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
+**
+**
the destination database was opened read-only, or
+**
the destination database is using write-ahead-log journaling
+** and the destination and source page sizes differ, or
+**
the destination database is an in-memory database and the
+** destination and source page sizes differ.
+**
)^
+**
+** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
+** the [sqlite3_busy_handler | busy-handler function]
+** is invoked (if one is specified). ^If the
+** busy-handler returns non-zero before the lock is available, then
+** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
+** sqlite3_backup_step() can be retried later. ^If the source
+** [database connection]
+** is being used to write to the source database when sqlite3_backup_step()
+** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
+** case the call to sqlite3_backup_step() can be retried later on. ^(If
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
+** [SQLITE_READONLY] is returned, then
+** there is no point in retrying the call to sqlite3_backup_step(). These
+** errors are considered fatal.)^ The application must accept
+** that the backup operation has failed and pass the backup operation handle
+** to the sqlite3_backup_finish() to release associated resources.
+**
+** ^The first call to sqlite3_backup_step() obtains an exclusive lock
+** on the destination file. ^The exclusive lock is not released until either
+** sqlite3_backup_finish() is called or the backup operation is complete
+** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
+** sqlite3_backup_step() obtains a [shared lock] on the source database that
+** lasts for the duration of the sqlite3_backup_step() call.
+** ^Because the source database is not locked between calls to
+** sqlite3_backup_step(), the source database may be modified mid-way
+** through the backup process. ^If the source database is modified by an
+** external process or via a database connection other than the one being
+** used by the backup operation, then the backup will be automatically
+** restarted by the next call to sqlite3_backup_step(). ^If the source
+** database is modified by the using the same database connection as is used
+** by the backup operation, then the backup database is automatically
+** updated at the same time.
+**
+** [[sqlite3_backup_finish()]] sqlite3_backup_finish()
+**
+** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
+** application wishes to abandon the backup operation, the application
+** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
+** ^The sqlite3_backup_finish() interfaces releases all
+** resources associated with the [sqlite3_backup] object.
+** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
+** active write-transaction on the destination database is rolled back.
+** The [sqlite3_backup] object is invalid
+** and may not be used following a call to sqlite3_backup_finish().
+**
+** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
+** sqlite3_backup_step() errors occurred, regardless or whether or not
+** sqlite3_backup_step() completed.
+** ^If an out-of-memory condition or IO error occurred during any prior
+** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
+** sqlite3_backup_finish() returns the corresponding [error code].
+**
+** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
+** is not a permanent error and does not affect the return value of
+** sqlite3_backup_finish().
+**
+** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
+** sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+**
+** ^The sqlite3_backup_remaining() routine returns the number of pages still
+** to be backed up at the conclusion of the most recent sqlite3_backup_step().
+** ^The sqlite3_backup_pagecount() routine returns the total number of pages
+** in the source database at the conclusion of the most recent
+** sqlite3_backup_step().
+** ^(The values returned by these functions are only updated by
+** sqlite3_backup_step(). If the source database is modified in a way that
+** changes the size of the source database or the number of pages remaining,
+** those changes are not reflected in the output of sqlite3_backup_pagecount()
+** and sqlite3_backup_remaining() until after the next
+** sqlite3_backup_step().)^
+**
+** Concurrent Usage of Database Handles
+**
+** ^The source [database connection] may be used by the application for other
+** purposes while a backup operation is underway or being initialized.
+** ^If SQLite is compiled and configured to support threadsafe database
+** connections, then the source database connection may be used concurrently
+** from within other threads.
+**
+** However, the application must guarantee that the destination
+** [database connection] is not passed to any other API (by any thread) after
+** sqlite3_backup_init() is called and before the corresponding call to
+** sqlite3_backup_finish(). SQLite does not currently check to see
+** if the application incorrectly accesses the destination [database connection]
+** and so no error code is reported, but the operations may malfunction
+** nevertheless. Use of the destination database connection while a
+** backup is in progress might also also cause a mutex deadlock.
+**
+** If running in [shared cache mode], the application must
+** guarantee that the shared cache used by the destination database
+** is not accessed while the backup is running. In practice this means
+** that the application must guarantee that the disk file being
+** backed up to is not accessed by any connection within the process,
+** not just the specific connection that was passed to sqlite3_backup_init().
+**
+** The [sqlite3_backup] object itself is partially threadsafe. Multiple
+** threads may safely make multiple concurrent calls to sqlite3_backup_step().
+** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+** APIs are not strictly speaking threadsafe. If they are invoked at the
+** same time as another thread is invoking sqlite3_backup_step() it is
+** possible that they return invalid values.
+*/
+SQLITE_API sqlite3_backup *sqlite3_backup_init(
+ sqlite3 *pDest, /* Destination database handle */
+ const char *zDestName, /* Destination database name */
+ sqlite3 *pSource, /* Source database handle */
+ const char *zSourceName /* Source database name */
+);
+SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
+SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
+
+/*
+** CAPI3REF: Unlock Notification
+** METHOD: sqlite3
+**
+** ^When running in shared-cache mode, a database operation may fail with
+** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
+** individual tables within the shared-cache cannot be obtained. See
+** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
+** ^This API may be used to register a callback that SQLite will invoke
+** when the connection currently holding the required lock relinquishes it.
+** ^This API is only available if the library was compiled with the
+** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
+**
+** See Also: [Using the SQLite Unlock Notification Feature].
+**
+** ^Shared-cache locks are released when a database connection concludes
+** its current transaction, either by committing it or rolling it back.
+**
+** ^When a connection (known as the blocked connection) fails to obtain a
+** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
+** identity of the database connection (the blocking connection) that
+** has locked the required resource is stored internally. ^After an
+** application receives an SQLITE_LOCKED error, it may call the
+** sqlite3_unlock_notify() method with the blocked connection handle as
+** the first argument to register for a callback that will be invoked
+** when the blocking connections current transaction is concluded. ^The
+** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
+** call that concludes the blocking connections transaction.
+**
+** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
+** there is a chance that the blocking connection will have already
+** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
+** If this happens, then the specified callback is invoked immediately,
+** from within the call to sqlite3_unlock_notify().)^
+**
+** ^If the blocked connection is attempting to obtain a write-lock on a
+** shared-cache table, and more than one other connection currently holds
+** a read-lock on the same table, then SQLite arbitrarily selects one of
+** the other connections to use as the blocking connection.
+**
+** ^(There may be at most one unlock-notify callback registered by a
+** blocked connection. If sqlite3_unlock_notify() is called when the
+** blocked connection already has a registered unlock-notify callback,
+** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
+** called with a NULL pointer as its second argument, then any existing
+** unlock-notify callback is canceled. ^The blocked connections
+** unlock-notify callback may also be canceled by closing the blocked
+** connection using [sqlite3_close()].
+**
+** The unlock-notify callback is not reentrant. If an application invokes
+** any sqlite3_xxx API functions from within an unlock-notify callback, a
+** crash or deadlock may be the result.
+**
+** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
+** returns SQLITE_OK.
+**
+** Callback Invocation Details
+**
+** When an unlock-notify callback is registered, the application provides a
+** single void* pointer that is passed to the callback when it is invoked.
+** However, the signature of the callback function allows SQLite to pass
+** it an array of void* context pointers. The first argument passed to
+** an unlock-notify callback is a pointer to an array of void* pointers,
+** and the second is the number of entries in the array.
+**
+** When a blocking connections transaction is concluded, there may be
+** more than one blocked connection that has registered for an unlock-notify
+** callback. ^If two or more such blocked connections have specified the
+** same callback function, then instead of invoking the callback function
+** multiple times, it is invoked once with the set of void* context pointers
+** specified by the blocked connections bundled together into an array.
+** This gives the application an opportunity to prioritize any actions
+** related to the set of unblocked database connections.
+**
+** Deadlock Detection
+**
+** Assuming that after registering for an unlock-notify callback a
+** database waits for the callback to be issued before taking any further
+** action (a reasonable assumption), then using this API may cause the
+** application to deadlock. For example, if connection X is waiting for
+** connection Y's transaction to be concluded, and similarly connection
+** Y is waiting on connection X's transaction, then neither connection
+** will proceed and the system may remain deadlocked indefinitely.
+**
+** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
+** detection. ^If a given call to sqlite3_unlock_notify() would put the
+** system in a deadlocked state, then SQLITE_LOCKED is returned and no
+** unlock-notify callback is registered. The system is said to be in
+** a deadlocked state if connection A has registered for an unlock-notify
+** callback on the conclusion of connection B's transaction, and connection
+** B has itself registered for an unlock-notify callback when connection
+** A's transaction is concluded. ^Indirect deadlock is also detected, so
+** the system is also considered to be deadlocked if connection B has
+** registered for an unlock-notify callback on the conclusion of connection
+** C's transaction, where connection C is waiting on connection A. ^Any
+** number of levels of indirection are allowed.
+**
+** The "DROP TABLE" Exception
+**
+** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
+** always appropriate to call sqlite3_unlock_notify(). There is however,
+** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
+** SQLite checks if there are any currently executing SELECT statements
+** that belong to the same connection. If there are, SQLITE_LOCKED is
+** returned. In this case there is no "blocking connection", so invoking
+** sqlite3_unlock_notify() results in the unlock-notify callback being
+** invoked immediately. If the application then re-attempts the "DROP TABLE"
+** or "DROP INDEX" query, an infinite loop might be the result.
+**
+** One way around this problem is to check the extended error code returned
+** by an sqlite3_step() call. ^(If there is a blocking connection, then the
+** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
+** the special "DROP TABLE/INDEX" case, the extended error code is just
+** SQLITE_LOCKED.)^
+*/
+SQLITE_API int sqlite3_unlock_notify(
+ sqlite3 *pBlocked, /* Waiting connection */
+ void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
+ void *pNotifyArg /* Argument to pass to xNotify */
+);
+
+
+/*
+** CAPI3REF: String Comparison
+**
+** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
+** and extensions to compare the contents of two buffers containing UTF-8
+** strings in a case-independent fashion, using the same definition of "case
+** independence" that SQLite uses internally when comparing identifiers.
+*/
+SQLITE_API int sqlite3_stricmp(const char *, const char *);
+SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
+
+/*
+** CAPI3REF: String Globbing
+*
+** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
+** string X matches the [GLOB] pattern P.
+** ^The definition of [GLOB] pattern matching used in
+** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
+** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function
+** is case sensitive.
+**
+** Note that this routine returns zero on a match and non-zero if the strings
+** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
+**
+** See also: [sqlite3_strlike()].
+*/
+SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
+
+/*
+** CAPI3REF: String LIKE Matching
+*
+** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
+** string X matches the [LIKE] pattern P with escape character E.
+** ^The definition of [LIKE] pattern matching used in
+** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
+** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without
+** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
+** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
+** insensitive - equivalent upper and lower case ASCII characters match
+** one another.
+**
+** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
+** only ASCII characters are case folded.
+**
+** Note that this routine returns zero on a match and non-zero if the strings
+** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
+**
+** See also: [sqlite3_strglob()].
+*/
+SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
+
+/*
+** CAPI3REF: Error Logging Interface
+**
+** ^The [sqlite3_log()] interface writes a message into the [error log]
+** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
+** ^If logging is enabled, the zFormat string and subsequent arguments are
+** used with [sqlite3_snprintf()] to generate the final output string.
+**
+** The sqlite3_log() interface is intended for use by extensions such as
+** virtual tables, collating functions, and SQL functions. While there is
+** nothing to prevent an application from calling sqlite3_log(), doing so
+** is considered bad form.
+**
+** The zFormat string must not be NULL.
+**
+** To avoid deadlocks and other threading problems, the sqlite3_log() routine
+** will not use dynamically allocated memory. The log message is stored in
+** a fixed-length buffer on the stack. If the log message is longer than
+** a few hundred characters, it will be truncated to the length of the
+** buffer.
+*/
+SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
+
+/*
+** CAPI3REF: Write-Ahead Log Commit Hook
+** METHOD: sqlite3
+**
+** ^The [sqlite3_wal_hook()] function is used to register a callback that
+** is invoked each time data is committed to a database in wal mode.
+**
+** ^(The callback is invoked by SQLite after the commit has taken place and
+** the associated write-lock on the database released)^, so the implementation
+** may read, write or [checkpoint] the database as required.
+**
+** ^The first parameter passed to the callback function when it is invoked
+** is a copy of the third parameter passed to sqlite3_wal_hook() when
+** registering the callback. ^The second is a copy of the database handle.
+** ^The third parameter is the name of the database that was written to -
+** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
+** is the number of pages currently in the write-ahead log file,
+** including those that were just committed.
+**
+** The callback function should normally return [SQLITE_OK]. ^If an error
+** code is returned, that error will propagate back up through the
+** SQLite code base to cause the statement that provoked the callback
+** to report an error, though the commit will have still occurred. If the
+** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
+** that does not correspond to any valid SQLite error code, the results
+** are undefined.
+**
+** A single database handle may have at most a single write-ahead log callback
+** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
+** previously registered write-ahead log callback. ^Note that the
+** [sqlite3_wal_autocheckpoint()] interface and the
+** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
+** overwrite any prior [sqlite3_wal_hook()] settings.
+*/
+SQLITE_API void *sqlite3_wal_hook(
+ sqlite3*,
+ int(*)(void *,sqlite3*,const char*,int),
+ void*
+);
+
+/*
+** CAPI3REF: Configure an auto-checkpoint
+** METHOD: sqlite3
+**
+** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
+** [sqlite3_wal_hook()] that causes any database on [database connection] D
+** to automatically [checkpoint]
+** after committing a transaction if there are N or
+** more frames in the [write-ahead log] file. ^Passing zero or
+** a negative value as the nFrame parameter disables automatic
+** checkpoints entirely.
+**
+** ^The callback registered by this function replaces any existing callback
+** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
+** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
+** configured by this function.
+**
+** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
+** from SQL.
+**
+** ^Checkpoints initiated by this mechanism are
+** [sqlite3_wal_checkpoint_v2|PASSIVE].
+**
+** ^Every new [database connection] defaults to having the auto-checkpoint
+** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
+** pages. The use of this interface
+** is only necessary if the default setting is found to be suboptimal
+** for a particular application.
+*/
+SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
+
+/*
+** CAPI3REF: Checkpoint a database
+** METHOD: sqlite3
+**
+** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
+** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
+**
+** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
+** [write-ahead log] for database X on [database connection] D to be
+** transferred into the database file and for the write-ahead log to
+** be reset. See the [checkpointing] documentation for addition
+** information.
+**
+** This interface used to be the only way to cause a checkpoint to
+** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
+** interface was added. This interface is retained for backwards
+** compatibility and as a convenience for applications that need to manually
+** start a callback but which do not need the full power (and corresponding
+** complication) of [sqlite3_wal_checkpoint_v2()].
+*/
+SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
+
+/*
+** CAPI3REF: Checkpoint a database
+** METHOD: sqlite3
+**
+** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
+** operation on database X of [database connection] D in mode M. Status
+** information is written back into integers pointed to by L and C.)^
+** ^(The M parameter must be a valid [checkpoint mode]:)^
+**
+**
+**
SQLITE_CHECKPOINT_PASSIVE
+** ^Checkpoint as many frames as possible without waiting for any database
+** readers or writers to finish, then sync the database file if all frames
+** in the log were checkpointed. ^The [busy-handler callback]
+** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
+** ^On the other hand, passive mode might leave the checkpoint unfinished
+** if there are concurrent readers or writers.
+**
+**
SQLITE_CHECKPOINT_FULL
+** ^This mode blocks (it invokes the
+** [sqlite3_busy_handler|busy-handler callback]) until there is no
+** database writer and all readers are reading from the most recent database
+** snapshot. ^It then checkpoints all frames in the log file and syncs the
+** database file. ^This mode blocks new database writers while it is pending,
+** but new database readers are allowed to continue unimpeded.
+**
+**
SQLITE_CHECKPOINT_RESTART
+** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
+** that after checkpointing the log file it blocks (calls the
+** [busy-handler callback])
+** until all readers are reading from the database file only. ^This ensures
+** that the next writer will restart the log file from the beginning.
+** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
+** database writer attempts while it is pending, but does not impede readers.
+**
+**
SQLITE_CHECKPOINT_TRUNCATE
+** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
+** addition that it also truncates the log file to zero bytes just prior
+** to a successful return.
+**
+**
+** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
+** the log file or to -1 if the checkpoint could not run because
+** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
+** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
+** log file (including any that were already checkpointed before the function
+** was called) or to -1 if the checkpoint could not run due to an error or
+** because the database is not in WAL mode. ^Note that upon successful
+** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
+** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
+**
+** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
+** any other process is running a checkpoint operation at the same time, the
+** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
+** busy-handler configured, it will not be invoked in this case.
+**
+** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
+** exclusive "writer" lock on the database file. ^If the writer lock cannot be
+** obtained immediately, and a busy-handler is configured, it is invoked and
+** the writer lock retried until either the busy-handler returns 0 or the lock
+** is successfully obtained. ^The busy-handler is also invoked while waiting for
+** database readers as described above. ^If the busy-handler returns 0 before
+** the writer lock is obtained or while waiting for database readers, the
+** checkpoint operation proceeds from that point in the same way as
+** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
+** without blocking any further. ^SQLITE_BUSY is returned in this case.
+**
+** ^If parameter zDb is NULL or points to a zero length string, then the
+** specified operation is attempted on all WAL databases [attached] to
+** [database connection] db. In this case the
+** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
+** an SQLITE_BUSY error is encountered when processing one or more of the
+** attached WAL databases, the operation is still attempted on any remaining
+** attached databases and SQLITE_BUSY is returned at the end. ^If any other
+** error occurs while processing an attached database, processing is abandoned
+** and the error code is returned to the caller immediately. ^If no error
+** (SQLITE_BUSY or otherwise) is encountered while processing the attached
+** databases, SQLITE_OK is returned.
+**
+** ^If database zDb is the name of an attached database that is not in WAL
+** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
+** zDb is not NULL (or a zero length string) and is not the name of any
+** attached database, SQLITE_ERROR is returned to the caller.
+**
+** ^Unless it returns SQLITE_MISUSE,
+** the sqlite3_wal_checkpoint_v2() interface
+** sets the error information that is queried by
+** [sqlite3_errcode()] and [sqlite3_errmsg()].
+**
+** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
+** from SQL.
+*/
+SQLITE_API int sqlite3_wal_checkpoint_v2(
+ sqlite3 *db, /* Database handle */
+ const char *zDb, /* Name of attached database (or NULL) */
+ int eMode, /* SQLITE_CHECKPOINT_* value */
+ int *pnLog, /* OUT: Size of WAL log in frames */
+ int *pnCkpt /* OUT: Total number of frames checkpointed */
+);
+
+/*
+** CAPI3REF: Checkpoint Mode Values
+** KEYWORDS: {checkpoint mode}
+**
+** These constants define all valid values for the "checkpoint mode" passed
+** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
+** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
+** meaning of each of these checkpoint modes.
+*/
+#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */
+#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */
+#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */
+#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */
+
+/*
+** CAPI3REF: Virtual Table Interface Configuration
+**
+** This function may be called by either the [xConnect] or [xCreate] method
+** of a [virtual table] implementation to configure
+** various facets of the virtual table interface.
+**
+** If this interface is invoked outside the context of an xConnect or
+** xCreate virtual table method then the behavior is undefined.
+**
+** At present, there is only one option that may be configured using
+** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options
+** may be added in the future.
+*/
+SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
+
+/*
+** CAPI3REF: Virtual Table Configuration Options
+**
+** These macros define the various options to the
+** [sqlite3_vtab_config()] interface that [virtual table] implementations
+** can use to customize and optimize their behavior.
+**
+**
+**
SQLITE_VTAB_CONSTRAINT_SUPPORT
+**
Calls of the form
+** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
+** where X is an integer. If X is zero, then the [virtual table] whose
+** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
+** support constraints. In this configuration (which is the default) if
+** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
+** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
+** specified as part of the users SQL statement, regardless of the actual
+** ON CONFLICT mode specified.
+**
+** If X is non-zero, then the virtual table implementation guarantees
+** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
+** any modifications to internal or persistent data structures have been made.
+** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
+** is able to roll back a statement or database transaction, and abandon
+** or continue processing the current SQL statement as appropriate.
+** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
+** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
+** had been ABORT.
+**
+** Virtual table implementations that are required to handle OR REPLACE
+** must do so within the [xUpdate] method. If a call to the
+** [sqlite3_vtab_on_conflict()] function indicates that the current ON
+** CONFLICT policy is REPLACE, the virtual table implementation should
+** silently replace the appropriate rows within the xUpdate callback and
+** return SQLITE_OK. Or, if this is not possible, it may return
+** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
+** constraint handling.
+**
+*/
+#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
+
+/*
+** CAPI3REF: Determine The Virtual Table Conflict Policy
+**
+** This function may only be called from within a call to the [xUpdate] method
+** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
+** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
+** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
+** of the SQL statement that triggered the call to the [xUpdate] method of the
+** [virtual table].
+*/
+SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
+
+/*
+** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE
+**
+** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn]
+** method of a [virtual table], then it returns true if and only if the
+** column is being fetched as part of an UPDATE operation during which the
+** column value will not change. Applications might use this to substitute
+** a return value that is less expensive to compute and that the corresponding
+** [xUpdate] method understands as a "no-change" value.
+**
+** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that
+** the column is not changed by the UPDATE statement, then the xColumn
+** method can optionally return without setting a result, without calling
+** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces].
+** In that case, [sqlite3_value_nochange(X)] will return true for the
+** same column in the [xUpdate] method.
+*/
+SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*);
+
+/*
+** CAPI3REF: Determine The Collation For a Virtual Table Constraint
+**
+** This function may only be called from within a call to the [xBestIndex]
+** method of a [virtual table].
+**
+** The first argument must be the sqlite3_index_info object that is the
+** first parameter to the xBestIndex() method. The second argument must be
+** an index into the aConstraint[] array belonging to the sqlite3_index_info
+** structure passed to xBestIndex. This function returns a pointer to a buffer
+** containing the name of the collation sequence for the corresponding
+** constraint.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int);
+
+/*
+** CAPI3REF: Conflict resolution modes
+** KEYWORDS: {conflict resolution mode}
+**
+** These constants are returned by [sqlite3_vtab_on_conflict()] to
+** inform a [virtual table] implementation what the [ON CONFLICT] mode
+** is for the SQL statement being evaluated.
+**
+** Note that the [SQLITE_IGNORE] constant is also used as a potential
+** return value from the [sqlite3_set_authorizer()] callback and that
+** [SQLITE_ABORT] is also a [result code].
+*/
+#define SQLITE_ROLLBACK 1
+/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
+#define SQLITE_FAIL 3
+/* #define SQLITE_ABORT 4 // Also an error code */
+#define SQLITE_REPLACE 5
+
+/*
+** CAPI3REF: Prepared Statement Scan Status Opcodes
+** KEYWORDS: {scanstatus options}
+**
+** The following constants can be used for the T parameter to the
+** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a
+** different metric for sqlite3_stmt_scanstatus() to return.
+**
+** When the value returned to V is a string, space to hold that string is
+** managed by the prepared statement S and will be automatically freed when
+** S is finalized.
+**
+**
+** [[SQLITE_SCANSTAT_NLOOP]]
SQLITE_SCANSTAT_NLOOP
+**
^The [sqlite3_int64] variable pointed to by the T parameter will be
+** set to the total number of times that the X-th loop has run.
+**
+** [[SQLITE_SCANSTAT_NVISIT]]
SQLITE_SCANSTAT_NVISIT
+**
^The [sqlite3_int64] variable pointed to by the T parameter will be set
+** to the total number of rows examined by all iterations of the X-th loop.
+**
+** [[SQLITE_SCANSTAT_EST]]
SQLITE_SCANSTAT_EST
+**
^The "double" variable pointed to by the T parameter will be set to the
+** query planner's estimate for the average number of rows output from each
+** iteration of the X-th loop. If the query planner's estimates was accurate,
+** then this value will approximate the quotient NVISIT/NLOOP and the
+** product of this value for all prior loops with the same SELECTID will
+** be the NLOOP value for the current loop.
+**
+** [[SQLITE_SCANSTAT_NAME]]
SQLITE_SCANSTAT_NAME
+**
^The "const char *" variable pointed to by the T parameter will be set
+** to a zero-terminated UTF-8 string containing the name of the index or table
+** used for the X-th loop.
+**
+** [[SQLITE_SCANSTAT_EXPLAIN]]
SQLITE_SCANSTAT_EXPLAIN
+**
^The "const char *" variable pointed to by the T parameter will be set
+** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
+** description for the X-th loop.
+**
+** [[SQLITE_SCANSTAT_SELECTID]]
SQLITE_SCANSTAT_SELECT
+**
^The "int" variable pointed to by the T parameter will be set to the
+** "select-id" for the X-th loop. The select-id identifies which query or
+** subquery the loop is part of. The main query has a select-id of zero.
+** The select-id is the same value as is output in the first column
+** of an [EXPLAIN QUERY PLAN] query.
+**
+*/
+#define SQLITE_SCANSTAT_NLOOP 0
+#define SQLITE_SCANSTAT_NVISIT 1
+#define SQLITE_SCANSTAT_EST 2
+#define SQLITE_SCANSTAT_NAME 3
+#define SQLITE_SCANSTAT_EXPLAIN 4
+#define SQLITE_SCANSTAT_SELECTID 5
+
+/*
+** CAPI3REF: Prepared Statement Scan Status
+** METHOD: sqlite3_stmt
+**
+** This interface returns information about the predicted and measured
+** performance for pStmt. Advanced applications can use this
+** interface to compare the predicted and the measured performance and
+** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
+**
+** Since this interface is expected to be rarely used, it is only
+** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
+** compile-time option.
+**
+** The "iScanStatusOp" parameter determines which status information to return.
+** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
+** of this interface is undefined.
+** ^The requested measurement is written into a variable pointed to by
+** the "pOut" parameter.
+** Parameter "idx" identifies the specific loop to retrieve statistics for.
+** Loops are numbered starting from zero. ^If idx is out of range - less than
+** zero or greater than or equal to the total number of loops used to implement
+** the statement - a non-zero value is returned and the variable that pOut
+** points to is unchanged.
+**
+** ^Statistics might not be available for all loops in all statements. ^In cases
+** where there exist loops with no available statistics, this function behaves
+** as if the loop did not exist - it returns non-zero and leave the variable
+** that pOut points to unchanged.
+**
+** See also: [sqlite3_stmt_scanstatus_reset()]
+*/
+SQLITE_API int sqlite3_stmt_scanstatus(
+ sqlite3_stmt *pStmt, /* Prepared statement for which info desired */
+ int idx, /* Index of loop to report on */
+ int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */
+ void *pOut /* Result written here */
+);
+
+/*
+** CAPI3REF: Zero Scan-Status Counters
+** METHOD: sqlite3_stmt
+**
+** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
+**
+** This API is only available if the library is built with pre-processor
+** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
+*/
+SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Flush caches to disk mid-transaction
+**
+** ^If a write-transaction is open on [database connection] D when the
+** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
+** pages in the pager-cache that are not currently in use are written out
+** to disk. A dirty page may be in use if a database cursor created by an
+** active SQL statement is reading from it, or if it is page 1 of a database
+** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)]
+** interface flushes caches for all schemas - "main", "temp", and
+** any [attached] databases.
+**
+** ^If this function needs to obtain extra database locks before dirty pages
+** can be flushed to disk, it does so. ^If those locks cannot be obtained
+** immediately and there is a busy-handler callback configured, it is invoked
+** in the usual manner. ^If the required lock still cannot be obtained, then
+** the database is skipped and an attempt made to flush any dirty pages
+** belonging to the next (if any) database. ^If any databases are skipped
+** because locks cannot be obtained, but no other error occurs, this
+** function returns SQLITE_BUSY.
+**
+** ^If any other error occurs while flushing dirty pages to disk (for
+** example an IO error or out-of-memory condition), then processing is
+** abandoned and an SQLite [error code] is returned to the caller immediately.
+**
+** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
+**
+** ^This function does not set the database handle error code or message
+** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
+*/
+SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
+
+/*
+** CAPI3REF: The pre-update hook.
+**
+** ^These interfaces are only available if SQLite is compiled using the
+** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
+**
+** ^The [sqlite3_preupdate_hook()] interface registers a callback function
+** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
+** on a database table.
+** ^At most one preupdate hook may be registered at a time on a single
+** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
+** the previous setting.
+** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
+** with a NULL pointer as the second parameter.
+** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
+** the first parameter to callbacks.
+**
+** ^The preupdate hook only fires for changes to real database tables; the
+** preupdate hook is not invoked for changes to [virtual tables] or to
+** system tables like sqlite_master or sqlite_stat1.
+**
+** ^The second parameter to the preupdate callback is a pointer to
+** the [database connection] that registered the preupdate hook.
+** ^The third parameter to the preupdate callback is one of the constants
+** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
+** kind of update operation that is about to occur.
+** ^(The fourth parameter to the preupdate callback is the name of the
+** database within the database connection that is being modified. This
+** will be "main" for the main database or "temp" for TEMP tables or
+** the name given after the AS keyword in the [ATTACH] statement for attached
+** databases.)^
+** ^The fifth parameter to the preupdate callback is the name of the
+** table that is being modified.
+**
+** For an UPDATE or DELETE operation on a [rowid table], the sixth
+** parameter passed to the preupdate callback is the initial [rowid] of the
+** row being modified or deleted. For an INSERT operation on a rowid table,
+** or any operation on a WITHOUT ROWID table, the value of the sixth
+** parameter is undefined. For an INSERT or UPDATE on a rowid table the
+** seventh parameter is the final rowid value of the row being inserted
+** or updated. The value of the seventh parameter passed to the callback
+** function is not defined for operations on WITHOUT ROWID tables, or for
+** INSERT operations on rowid tables.
+**
+** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
+** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
+** provide additional information about a preupdate event. These routines
+** may only be called from within a preupdate callback. Invoking any of
+** these routines from outside of a preupdate callback or with a
+** [database connection] pointer that is different from the one supplied
+** to the preupdate callback results in undefined and probably undesirable
+** behavior.
+**
+** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
+** in the row that is being inserted, updated, or deleted.
+**
+** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
+** a [protected sqlite3_value] that contains the value of the Nth column of
+** the table row before it is updated. The N parameter must be between 0
+** and one less than the number of columns or the behavior will be
+** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
+** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
+** behavior is undefined. The [sqlite3_value] that P points to
+** will be destroyed when the preupdate callback returns.
+**
+** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
+** a [protected sqlite3_value] that contains the value of the Nth column of
+** the table row after it is updated. The N parameter must be between 0
+** and one less than the number of columns or the behavior will be
+** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
+** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
+** behavior is undefined. The [sqlite3_value] that P points to
+** will be destroyed when the preupdate callback returns.
+**
+** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
+** callback was invoked as a result of a direct insert, update, or delete
+** operation; or 1 for inserts, updates, or deletes invoked by top-level
+** triggers; or 2 for changes resulting from triggers called by top-level
+** triggers; and so forth.
+**
+** See also: [sqlite3_update_hook()]
+*/
+#if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
+SQLITE_API void *sqlite3_preupdate_hook(
+ sqlite3 *db,
+ void(*xPreUpdate)(
+ void *pCtx, /* Copy of third arg to preupdate_hook() */
+ sqlite3 *db, /* Database handle */
+ int op, /* SQLITE_UPDATE, DELETE or INSERT */
+ char const *zDb, /* Database name */
+ char const *zName, /* Table name */
+ sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */
+ sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */
+ ),
+ void*
+);
+SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
+SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
+SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
+SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
+#endif
+
+/*
+** CAPI3REF: Low-level system error code
+**
+** ^Attempt to return the underlying operating system error code or error
+** number that caused the most recent I/O error or failure to open a file.
+** The return value is OS-dependent. For example, on unix systems, after
+** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
+** called to get back the underlying "errno" that caused the problem, such
+** as ENOSPC, EAUTH, EISDIR, and so forth.
+*/
+SQLITE_API int sqlite3_system_errno(sqlite3*);
+
+/*
+** CAPI3REF: Database Snapshot
+** KEYWORDS: {snapshot} {sqlite3_snapshot}
+**
+** An instance of the snapshot object records the state of a [WAL mode]
+** database for some specific point in history.
+**
+** In [WAL mode], multiple [database connections] that are open on the
+** same database file can each be reading a different historical version
+** of the database file. When a [database connection] begins a read
+** transaction, that connection sees an unchanging copy of the database
+** as it existed for the point in time when the transaction first started.
+** Subsequent changes to the database from other connections are not seen
+** by the reader until a new read transaction is started.
+**
+** The sqlite3_snapshot object records state information about an historical
+** version of the database file so that it is possible to later open a new read
+** transaction that sees that historical version of the database rather than
+** the most recent version.
+*/
+typedef struct sqlite3_snapshot {
+ unsigned char hidden[48];
+} sqlite3_snapshot;
+
+/*
+** CAPI3REF: Record A Database Snapshot
+** CONSTRUCTOR: sqlite3_snapshot
+**
+** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
+** new [sqlite3_snapshot] object that records the current state of
+** schema S in database connection D. ^On success, the
+** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
+** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
+** If there is not already a read-transaction open on schema S when
+** this function is called, one is opened automatically.
+**
+** The following must be true for this function to succeed. If any of
+** the following statements are false when sqlite3_snapshot_get() is
+** called, SQLITE_ERROR is returned. The final value of *P is undefined
+** in this case.
+**
+**
+**
The database handle must not be in [autocommit mode].
+**
+**
Schema S of [database connection] D must be a [WAL mode] database.
+**
+**
There must not be a write transaction open on schema S of database
+** connection D.
+**
+**
One or more transactions must have been written to the current wal
+** file since it was created on disk (by any connection). This means
+** that a snapshot cannot be taken on a wal mode database with no wal
+** file immediately after it is first opened. At least one transaction
+** must be written to it first.
+**
+**
+** This function may also return SQLITE_NOMEM. If it is called with the
+** database handle in autocommit mode but fails for some other reason,
+** whether or not a read transaction is opened on schema S is undefined.
+**
+** The [sqlite3_snapshot] object returned from a successful call to
+** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
+** to avoid a memory leak.
+**
+** The [sqlite3_snapshot_get()] interface is only available when the
+** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
+ sqlite3 *db,
+ const char *zSchema,
+ sqlite3_snapshot **ppSnapshot
+);
+
+/*
+** CAPI3REF: Start a read transaction on an historical snapshot
+** METHOD: sqlite3_snapshot
+**
+** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read
+** transaction or upgrades an existing one for schema S of
+** [database connection] D such that the read transaction refers to
+** historical [snapshot] P, rather than the most recent change to the
+** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK
+** on success or an appropriate [error code] if it fails.
+**
+** ^In order to succeed, the database connection must not be in
+** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there
+** is already a read transaction open on schema S, then the database handle
+** must have no active statements (SELECT statements that have been passed
+** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()).
+** SQLITE_ERROR is returned if either of these conditions is violated, or
+** if schema S does not exist, or if the snapshot object is invalid.
+**
+** ^A call to sqlite3_snapshot_open() will fail to open if the specified
+** snapshot has been overwritten by a [checkpoint]. In this case
+** SQLITE_ERROR_SNAPSHOT is returned.
+**
+** If there is already a read transaction open when this function is
+** invoked, then the same read transaction remains open (on the same
+** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT
+** is returned. If another error code - for example SQLITE_PROTOCOL or an
+** SQLITE_IOERR error code - is returned, then the final state of the
+** read transaction is undefined. If SQLITE_OK is returned, then the
+** read transaction is now open on database snapshot P.
+**
+** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
+** database connection D does not know that the database file for
+** schema S is in [WAL mode]. A database connection might not know
+** that the database file is in [WAL mode] if there has been no prior
+** I/O on that database connection, or if the database entered [WAL mode]
+** after the most recent I/O on the database connection.)^
+** (Hint: Run "[PRAGMA application_id]" against a newly opened
+** database connection in order to make it ready to use snapshots.)
+**
+** The [sqlite3_snapshot_open()] interface is only available when the
+** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
+ sqlite3 *db,
+ const char *zSchema,
+ sqlite3_snapshot *pSnapshot
+);
+
+/*
+** CAPI3REF: Destroy a snapshot
+** DESTRUCTOR: sqlite3_snapshot
+**
+** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
+** The application must eventually free every [sqlite3_snapshot] object
+** using this routine to avoid a memory leak.
+**
+** The [sqlite3_snapshot_free()] interface is only available when the
+** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);
+
+/*
+** CAPI3REF: Compare the ages of two snapshot handles.
+** METHOD: sqlite3_snapshot
+**
+** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
+** of two valid snapshot handles.
+**
+** If the two snapshot handles are not associated with the same database
+** file, the result of the comparison is undefined.
+**
+** Additionally, the result of the comparison is only valid if both of the
+** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
+** last time the wal file was deleted. The wal file is deleted when the
+** database is changed back to rollback mode or when the number of database
+** clients drops to zero. If either snapshot handle was obtained before the
+** wal file was last deleted, the value returned by this function
+** is undefined.
+**
+** Otherwise, this API returns a negative value if P1 refers to an older
+** snapshot than P2, zero if the two handles refer to the same database
+** snapshot, and a positive value if P1 is a newer snapshot than P2.
+**
+** This interface is only available if SQLite is compiled with the
+** [SQLITE_ENABLE_SNAPSHOT] option.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
+ sqlite3_snapshot *p1,
+ sqlite3_snapshot *p2
+);
+
+/*
+** CAPI3REF: Recover snapshots from a wal file
+** METHOD: sqlite3_snapshot
+**
+** If a [WAL file] remains on disk after all database connections close
+** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control]
+** or because the last process to have the database opened exited without
+** calling [sqlite3_close()]) and a new connection is subsequently opened
+** on that database and [WAL file], the [sqlite3_snapshot_open()] interface
+** will only be able to open the last transaction added to the WAL file
+** even though the WAL file contains other valid transactions.
+**
+** This function attempts to scan the WAL file associated with database zDb
+** of database handle db and make all valid snapshots available to
+** sqlite3_snapshot_open(). It is an error if there is already a read
+** transaction open on the database, or if the database is not a WAL mode
+** database.
+**
+** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
+**
+** This interface is only available if SQLite is compiled with the
+** [SQLITE_ENABLE_SNAPSHOT] option.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
+
+/*
+** CAPI3REF: Serialize a database
+**
+** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory
+** that is a serialization of the S database on [database connection] D.
+** If P is not a NULL pointer, then the size of the database in bytes
+** is written into *P.
+**
+** For an ordinary on-disk database file, the serialization is just a
+** copy of the disk file. For an in-memory database or a "TEMP" database,
+** the serialization is the same sequence of bytes which would be written
+** to disk if that database where backed up to disk.
+**
+** The usual case is that sqlite3_serialize() copies the serialization of
+** the database into memory obtained from [sqlite3_malloc64()] and returns
+** a pointer to that memory. The caller is responsible for freeing the
+** returned value to avoid a memory leak. However, if the F argument
+** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations
+** are made, and the sqlite3_serialize() function will return a pointer
+** to the contiguous memory representation of the database that SQLite
+** is currently using for that database, or NULL if the no such contiguous
+** memory representation of the database exists. A contiguous memory
+** representation of the database will usually only exist if there has
+** been a prior call to [sqlite3_deserialize(D,S,...)] with the same
+** values of D and S.
+** The size of the database is written into *P even if the
+** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy
+** of the database exists.
+**
+** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the
+** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory
+** allocation error occurs.
+**
+** This interface is only available if SQLite is compiled with the
+** [SQLITE_ENABLE_DESERIALIZE] option.
+*/
+SQLITE_API unsigned char *sqlite3_serialize(
+ sqlite3 *db, /* The database connection */
+ const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */
+ sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */
+ unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */
+);
+
+/*
+** CAPI3REF: Flags for sqlite3_serialize
+**
+** Zero or more of the following constants can be OR-ed together for
+** the F argument to [sqlite3_serialize(D,S,P,F)].
+**
+** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return
+** a pointer to contiguous in-memory database that it is currently using,
+** without making a copy of the database. If SQLite is not currently using
+** a contiguous in-memory database, then this option causes
+** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be
+** using a contiguous in-memory database if it has been initialized by a
+** prior call to [sqlite3_deserialize()].
+*/
+#define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */
+
+/*
+** CAPI3REF: Deserialize a database
+**
+** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the
+** [database connection] D to disconnect from database S and then
+** reopen S as an in-memory database based on the serialization contained
+** in P. The serialized database P is N bytes in size. M is the size of
+** the buffer P, which might be larger than N. If M is larger than N, and
+** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is
+** permitted to add content to the in-memory database as long as the total
+** size does not exceed M bytes.
+**
+** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will
+** invoke sqlite3_free() on the serialization buffer when the database
+** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then
+** SQLite will try to increase the buffer size using sqlite3_realloc64()
+** if writes on the database cause it to grow larger than M bytes.
+**
+** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the
+** database is currently in a read transaction or is involved in a backup
+** operation.
+**
+** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the
+** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then
+** [sqlite3_free()] is invoked on argument P prior to returning.
+**
+** This interface is only available if SQLite is compiled with the
+** [SQLITE_ENABLE_DESERIALIZE] option.
+*/
+SQLITE_API int sqlite3_deserialize(
+ sqlite3 *db, /* The database connection */
+ const char *zSchema, /* Which DB to reopen with the deserialization */
+ unsigned char *pData, /* The serialized database content */
+ sqlite3_int64 szDb, /* Number bytes in the deserialization */
+ sqlite3_int64 szBuf, /* Total size of buffer pData[] */
+ unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */
+);
+
+/*
+** CAPI3REF: Flags for sqlite3_deserialize()
+**
+** The following are allowed values for 6th argument (the F argument) to
+** the [sqlite3_deserialize(D,S,P,N,M,F)] interface.
+**
+** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization
+** in the P argument is held in memory obtained from [sqlite3_malloc64()]
+** and that SQLite should take ownership of this memory and automatically
+** free it when it has finished using it. Without this flag, the caller
+** is responsible for freeing any dynamically allocated memory.
+**
+** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to
+** grow the size of the database using calls to [sqlite3_realloc64()]. This
+** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used.
+** Without this flag, the deserialized database cannot increase in size beyond
+** the number of bytes specified by the M parameter.
+**
+** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database
+** should be treated as read-only.
+*/
+#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */
+#define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */
+#define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */
+
+/*
+** Undo the hack that converts floating point types to integer for
+** builds on processors without floating point support.
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# undef double
+#endif
+
+#if 0
+} /* End of the 'extern "C"' block */
+#endif
+#endif /* SQLITE3_H */
+
+/******** Begin file sqlite3rtree.h *********/
+/*
+** 2010 August 30
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+*/
+
+#ifndef _SQLITE3RTREE_H_
+#define _SQLITE3RTREE_H_
+
+
+#if 0
+extern "C" {
+#endif
+
+typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
+typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
+
+/* The double-precision datatype used by RTree depends on the
+** SQLITE_RTREE_INT_ONLY compile-time option.
+*/
+#ifdef SQLITE_RTREE_INT_ONLY
+ typedef sqlite3_int64 sqlite3_rtree_dbl;
+#else
+ typedef double sqlite3_rtree_dbl;
+#endif
+
+/*
+** Register a geometry callback named zGeom that can be used as part of an
+** R-Tree geometry query as follows:
+**
+** SELECT ... FROM WHERE MATCH $zGeom(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+ sqlite3 *db,
+ const char *zGeom,
+ int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
+ void *pContext
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the first
+** argument to callbacks registered using rtree_geometry_callback().
+*/
+struct sqlite3_rtree_geometry {
+ void *pContext; /* Copy of pContext passed to s_r_g_c() */
+ int nParam; /* Size of array aParam[] */
+ sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */
+ void *pUser; /* Callback implementation user data */
+ void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
+};
+
+/*
+** Register a 2nd-generation geometry callback named zScore that can be
+** used as part of an R-Tree geometry query as follows:
+**
+** SELECT ... FROM WHERE MATCH $zQueryFunc(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_query_callback(
+ sqlite3 *db,
+ const char *zQueryFunc,
+ int (*xQueryFunc)(sqlite3_rtree_query_info*),
+ void *pContext,
+ void (*xDestructor)(void*)
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the
+** argument to scored geometry callback registered using
+** sqlite3_rtree_query_callback().
+**
+** Note that the first 5 fields of this structure are identical to
+** sqlite3_rtree_geometry. This structure is a subclass of
+** sqlite3_rtree_geometry.
+*/
+struct sqlite3_rtree_query_info {
+ void *pContext; /* pContext from when function registered */
+ int nParam; /* Number of function parameters */
+ sqlite3_rtree_dbl *aParam; /* value of function parameters */
+ void *pUser; /* callback can use this, if desired */
+ void (*xDelUser)(void*); /* function to free pUser */
+ sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */
+ unsigned int *anQueue; /* Number of pending entries in the queue */
+ int nCoord; /* Number of coordinates */
+ int iLevel; /* Level of current node or entry */
+ int mxLevel; /* The largest iLevel value in the tree */
+ sqlite3_int64 iRowid; /* Rowid for current entry */
+ sqlite3_rtree_dbl rParentScore; /* Score of parent node */
+ int eParentWithin; /* Visibility of parent node */
+ int eWithin; /* OUT: Visiblity */
+ sqlite3_rtree_dbl rScore; /* OUT: Write the score here */
+ /* The following fields are only available in 3.8.11 and later */
+ sqlite3_value **apSqlParam; /* Original SQL values of parameters */
+};
+
+/*
+** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
+*/
+#define NOT_WITHIN 0 /* Object completely outside of query region */
+#define PARTLY_WITHIN 1 /* Object partially overlaps query region */
+#define FULLY_WITHIN 2 /* Object fully contained within query region */
+
+
+#if 0
+} /* end of the 'extern "C"' block */
+#endif
+
+#endif /* ifndef _SQLITE3RTREE_H_ */
+
+/******** End of sqlite3rtree.h *********/
+/******** Begin file sqlite3session.h *********/
+
+#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
+#define __SQLITESESSION_H_ 1
+
+/*
+** Make sure we can call this stuff from C++.
+*/
+#if 0
+extern "C" {
+#endif
+
+
+/*
+** CAPI3REF: Session Object Handle
+**
+** An instance of this object is a [session] that can be used to
+** record changes to a database.
+*/
+typedef struct sqlite3_session sqlite3_session;
+
+/*
+** CAPI3REF: Changeset Iterator Handle
+**
+** An instance of this object acts as a cursor for iterating
+** over the elements of a [changeset] or [patchset].
+*/
+typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
+
+/*
+** CAPI3REF: Create A New Session Object
+** CONSTRUCTOR: sqlite3_session
+**
+** Create a new session object attached to database handle db. If successful,
+** a pointer to the new object is written to *ppSession and SQLITE_OK is
+** returned. If an error occurs, *ppSession is set to NULL and an SQLite
+** error code (e.g. SQLITE_NOMEM) is returned.
+**
+** It is possible to create multiple session objects attached to a single
+** database handle.
+**
+** Session objects created using this function should be deleted using the
+** [sqlite3session_delete()] function before the database handle that they
+** are attached to is itself closed. If the database handle is closed before
+** the session object is deleted, then the results of calling any session
+** module function, including [sqlite3session_delete()] on the session object
+** are undefined.
+**
+** Because the session module uses the [sqlite3_preupdate_hook()] API, it
+** is not possible for an application to register a pre-update hook on a
+** database handle that has one or more session objects attached. Nor is
+** it possible to create a session object attached to a database handle for
+** which a pre-update hook is already defined. The results of attempting
+** either of these things are undefined.
+**
+** The session object will be used to create changesets for tables in
+** database zDb, where zDb is either "main", or "temp", or the name of an
+** attached database. It is not an error if database zDb is not attached
+** to the database when the session object is created.
+*/
+SQLITE_API int sqlite3session_create(
+ sqlite3 *db, /* Database handle */
+ const char *zDb, /* Name of db (e.g. "main") */
+ sqlite3_session **ppSession /* OUT: New session object */
+);
+
+/*
+** CAPI3REF: Delete A Session Object
+** DESTRUCTOR: sqlite3_session
+**
+** Delete a session object previously allocated using
+** [sqlite3session_create()]. Once a session object has been deleted, the
+** results of attempting to use pSession with any other session module
+** function are undefined.
+**
+** Session objects must be deleted before the database handle to which they
+** are attached is closed. Refer to the documentation for
+** [sqlite3session_create()] for details.
+*/
+SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
+
+
+/*
+** CAPI3REF: Enable Or Disable A Session Object
+** METHOD: sqlite3_session
+**
+** Enable or disable the recording of changes by a session object. When
+** enabled, a session object records changes made to the database. When
+** disabled - it does not. A newly created session object is enabled.
+** Refer to the documentation for [sqlite3session_changeset()] for further
+** details regarding how enabling and disabling a session object affects
+** the eventual changesets.
+**
+** Passing zero to this function disables the session. Passing a value
+** greater than zero enables it. Passing a value less than zero is a
+** no-op, and may be used to query the current state of the session.
+**
+** The return value indicates the final state of the session object: 0 if
+** the session is disabled, or 1 if it is enabled.
+*/
+SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
+
+/*
+** CAPI3REF: Set Or Clear the Indirect Change Flag
+** METHOD: sqlite3_session
+**
+** Each change recorded by a session object is marked as either direct or
+** indirect. A change is marked as indirect if either:
+**
+**
+**
The session object "indirect" flag is set when the change is
+** made, or
+**
The change is made by an SQL trigger or foreign key action
+** instead of directly as a result of a users SQL statement.
+**
+**
+** If a single row is affected by more than one operation within a session,
+** then the change is considered indirect if all operations meet the criteria
+** for an indirect change above, or direct otherwise.
+**
+** This function is used to set, clear or query the session object indirect
+** flag. If the second argument passed to this function is zero, then the
+** indirect flag is cleared. If it is greater than zero, the indirect flag
+** is set. Passing a value less than zero does not modify the current value
+** of the indirect flag, and may be used to query the current state of the
+** indirect flag for the specified session object.
+**
+** The return value indicates the final state of the indirect flag: 0 if
+** it is clear, or 1 if it is set.
+*/
+SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
+
+/*
+** CAPI3REF: Attach A Table To A Session Object
+** METHOD: sqlite3_session
+**
+** If argument zTab is not NULL, then it is the name of a table to attach
+** to the session object passed as the first argument. All subsequent changes
+** made to the table while the session object is enabled will be recorded. See
+** documentation for [sqlite3session_changeset()] for further details.
+**
+** Or, if argument zTab is NULL, then changes are recorded for all tables
+** in the database. If additional tables are added to the database (by
+** executing "CREATE TABLE" statements) after this call is made, changes for
+** the new tables are also recorded.
+**
+** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
+** defined as part of their CREATE TABLE statement. It does not matter if the
+** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
+** KEY may consist of a single column, or may be a composite key.
+**
+** It is not an error if the named table does not exist in the database. Nor
+** is it an error if the named table does not have a PRIMARY KEY. However,
+** no changes will be recorded in either of these scenarios.
+**
+** Changes are not recorded for individual rows that have NULL values stored
+** in one or more of their PRIMARY KEY columns.
+**
+** SQLITE_OK is returned if the call completes without error. Or, if an error
+** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
+**
+**
Special sqlite_stat1 Handling
+**
+** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to
+** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
+**
+** CREATE TABLE sqlite_stat1(tbl,idx,stat)
+**
+**
+** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are
+** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes
+** are recorded for rows for which (idx IS NULL) is true. However, for such
+** rows a zero-length blob (SQL value X'') is stored in the changeset or
+** patchset instead of a NULL value. This allows such changesets to be
+** manipulated by legacy implementations of sqlite3changeset_invert(),
+** concat() and similar.
+**
+** The sqlite3changeset_apply() function automatically converts the
+** zero-length blob back to a NULL value when updating the sqlite_stat1
+** table. However, if the application calls sqlite3changeset_new(),
+** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset
+** iterator directly (including on a changeset iterator passed to a
+** conflict-handler callback) then the X'' value is returned. The application
+** must translate X'' to NULL itself if required.
+**
+** Legacy (older than 3.22.0) versions of the sessions module cannot capture
+** changes made to the sqlite_stat1 table. Legacy versions of the
+** sqlite3changeset_apply() function silently ignore any modifications to the
+** sqlite_stat1 table that are part of a changeset or patchset.
+*/
+SQLITE_API int sqlite3session_attach(
+ sqlite3_session *pSession, /* Session object */
+ const char *zTab /* Table name */
+);
+
+/*
+** CAPI3REF: Set a table filter on a Session Object.
+** METHOD: sqlite3_session
+**
+** The second argument (xFilter) is the "filter callback". For changes to rows
+** in tables that are not attached to the Session object, the filter is called
+** to determine whether changes to the table's rows should be tracked or not.
+** If xFilter returns 0, changes is not tracked. Note that once a table is
+** attached, xFilter will not be called again.
+*/
+SQLITE_API void sqlite3session_table_filter(
+ sqlite3_session *pSession, /* Session object */
+ int(*xFilter)(
+ void *pCtx, /* Copy of third arg to _filter_table() */
+ const char *zTab /* Table name */
+ ),
+ void *pCtx /* First argument passed to xFilter */
+);
+
+/*
+** CAPI3REF: Generate A Changeset From A Session Object
+** METHOD: sqlite3_session
+**
+** Obtain a changeset containing changes to the tables attached to the
+** session object passed as the first argument. If successful,
+** set *ppChangeset to point to a buffer containing the changeset
+** and *pnChangeset to the size of the changeset in bytes before returning
+** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
+** zero and return an SQLite error code.
+**
+** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
+** each representing a change to a single row of an attached table. An INSERT
+** change contains the values of each field of a new database row. A DELETE
+** contains the original values of each field of a deleted database row. An
+** UPDATE change contains the original values of each field of an updated
+** database row along with the updated values for each updated non-primary-key
+** column. It is not possible for an UPDATE change to represent a change that
+** modifies the values of primary key columns. If such a change is made, it
+** is represented in a changeset as a DELETE followed by an INSERT.
+**
+** Changes are not recorded for rows that have NULL values stored in one or
+** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
+** no corresponding change is present in the changesets returned by this
+** function. If an existing row with one or more NULL values stored in
+** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
+** only an INSERT is appears in the changeset. Similarly, if an existing row
+** with non-NULL PRIMARY KEY values is updated so that one or more of its
+** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
+** DELETE change only.
+**
+** The contents of a changeset may be traversed using an iterator created
+** using the [sqlite3changeset_start()] API. A changeset may be applied to
+** a database with a compatible schema using the [sqlite3changeset_apply()]
+** API.
+**
+** Within a changeset generated by this function, all changes related to a
+** single table are grouped together. In other words, when iterating through
+** a changeset or when applying a changeset to a database, all changes related
+** to a single table are processed before moving on to the next table. Tables
+** are sorted in the same order in which they were attached (or auto-attached)
+** to the sqlite3_session object. The order in which the changes related to
+** a single table are stored is undefined.
+**
+** Following a successful call to this function, it is the responsibility of
+** the caller to eventually free the buffer that *ppChangeset points to using
+** [sqlite3_free()].
+**
+**
Changeset Generation
+**
+** Once a table has been attached to a session object, the session object
+** records the primary key values of all new rows inserted into the table.
+** It also records the original primary key and other column values of any
+** deleted or updated rows. For each unique primary key value, data is only
+** recorded once - the first time a row with said primary key is inserted,
+** updated or deleted in the lifetime of the session.
+**
+** There is one exception to the previous paragraph: when a row is inserted,
+** updated or deleted, if one or more of its primary key columns contain a
+** NULL value, no record of the change is made.
+**
+** The session object therefore accumulates two types of records - those
+** that consist of primary key values only (created when the user inserts
+** a new record) and those that consist of the primary key values and the
+** original values of other table columns (created when the users deletes
+** or updates a record).
+**
+** When this function is called, the requested changeset is created using
+** both the accumulated records and the current contents of the database
+** file. Specifically:
+**
+**
+**
For each record generated by an insert, the database is queried
+** for a row with a matching primary key. If one is found, an INSERT
+** change is added to the changeset. If no such row is found, no change
+** is added to the changeset.
+**
+**
For each record generated by an update or delete, the database is
+** queried for a row with a matching primary key. If such a row is
+** found and one or more of the non-primary key fields have been
+** modified from their original values, an UPDATE change is added to
+** the changeset. Or, if no such row is found in the table, a DELETE
+** change is added to the changeset. If there is a row with a matching
+** primary key in the database, but all fields contain their original
+** values, no change is added to the changeset.
+**
+**
+** This means, amongst other things, that if a row is inserted and then later
+** deleted while a session object is active, neither the insert nor the delete
+** will be present in the changeset. Or if a row is deleted and then later a
+** row with the same primary key values inserted while a session object is
+** active, the resulting changeset will contain an UPDATE change instead of
+** a DELETE and an INSERT.
+**
+** When a session object is disabled (see the [sqlite3session_enable()] API),
+** it does not accumulate records when rows are inserted, updated or deleted.
+** This may appear to have some counter-intuitive effects if a single row
+** is written to more than once during a session. For example, if a row
+** is inserted while a session object is enabled, then later deleted while
+** the same session object is disabled, no INSERT record will appear in the
+** changeset, even though the delete took place while the session was disabled.
+** Or, if one field of a row is updated while a session is disabled, and
+** another field of the same row is updated while the session is enabled, the
+** resulting changeset will contain an UPDATE change that updates both fields.
+*/
+SQLITE_API int sqlite3session_changeset(
+ sqlite3_session *pSession, /* Session object */
+ int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */
+ void **ppChangeset /* OUT: Buffer containing changeset */
+);
+
+/*
+** CAPI3REF: Load The Difference Between Tables Into A Session
+** METHOD: sqlite3_session
+**
+** If it is not already attached to the session object passed as the first
+** argument, this function attaches table zTbl in the same manner as the
+** [sqlite3session_attach()] function. If zTbl does not exist, or if it
+** does not have a primary key, this function is a no-op (but does not return
+** an error).
+**
+** Argument zFromDb must be the name of a database ("main", "temp" etc.)
+** attached to the same database handle as the session object that contains
+** a table compatible with the table attached to the session by this function.
+** A table is considered compatible if it:
+**
+**
+**
Has the same name,
+**
Has the same set of columns declared in the same order, and
+**
Has the same PRIMARY KEY definition.
+**
+**
+** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
+** are compatible but do not have any PRIMARY KEY columns, it is not an error
+** but no changes are added to the session object. As with other session
+** APIs, tables without PRIMARY KEYs are simply ignored.
+**
+** This function adds a set of changes to the session object that could be
+** used to update the table in database zFrom (call this the "from-table")
+** so that its content is the same as the table attached to the session
+** object (call this the "to-table"). Specifically:
+**
+**
+**
For each row (primary key) that exists in the to-table but not in
+** the from-table, an INSERT record is added to the session object.
+**
+**
For each row (primary key) that exists in the to-table but not in
+** the from-table, a DELETE record is added to the session object.
+**
+**
For each row (primary key) that exists in both tables, but features
+** different non-PK values in each, an UPDATE record is added to the
+** session.
+**
+**
+** To clarify, if this function is called and then a changeset constructed
+** using [sqlite3session_changeset()], then after applying that changeset to
+** database zFrom the contents of the two compatible tables would be
+** identical.
+**
+** It an error if database zFrom does not exist or does not contain the
+** required compatible table.
+**
+** If the operation successful, SQLITE_OK is returned. Otherwise, an SQLite
+** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
+** may be set to point to a buffer containing an English language error
+** message. It is the responsibility of the caller to free this buffer using
+** sqlite3_free().
+*/
+SQLITE_API int sqlite3session_diff(
+ sqlite3_session *pSession,
+ const char *zFromDb,
+ const char *zTbl,
+ char **pzErrMsg
+);
+
+
+/*
+** CAPI3REF: Generate A Patchset From A Session Object
+** METHOD: sqlite3_session
+**
+** The differences between a patchset and a changeset are that:
+**
+**
+**
DELETE records consist of the primary key fields only. The
+** original values of other fields are omitted.
+**
The original values of any modified fields are omitted from
+** UPDATE records.
+**
+**
+** A patchset blob may be used with up to date versions of all
+** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
+** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
+** attempting to use a patchset blob with old versions of the
+** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
+**
+** Because the non-primary key "old.*" fields are omitted, no
+** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
+** is passed to the sqlite3changeset_apply() API. Other conflict types work
+** in the same way as for changesets.
+**
+** Changes within a patchset are ordered in the same way as for changesets
+** generated by the sqlite3session_changeset() function (i.e. all changes for
+** a single table are grouped together, tables appear in the order in which
+** they were attached to the session object).
+*/
+SQLITE_API int sqlite3session_patchset(
+ sqlite3_session *pSession, /* Session object */
+ int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */
+ void **ppPatchset /* OUT: Buffer containing patchset */
+);
+
+/*
+** CAPI3REF: Test if a changeset has recorded any changes.
+**
+** Return non-zero if no changes to attached tables have been recorded by
+** the session object passed as the first argument. Otherwise, if one or
+** more changes have been recorded, return zero.
+**
+** Even if this function returns zero, it is possible that calling
+** [sqlite3session_changeset()] on the session handle may still return a
+** changeset that contains no changes. This can happen when a row in
+** an attached table is modified and then later on the original values
+** are restored. However, if this function returns non-zero, then it is
+** guaranteed that a call to sqlite3session_changeset() will return a
+** changeset containing zero changes.
+*/
+SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
+
+/*
+** CAPI3REF: Create An Iterator To Traverse A Changeset
+** CONSTRUCTOR: sqlite3_changeset_iter
+**
+** Create an iterator used to iterate through the contents of a changeset.
+** If successful, *pp is set to point to the iterator handle and SQLITE_OK
+** is returned. Otherwise, if an error occurs, *pp is set to zero and an
+** SQLite error code is returned.
+**
+** The following functions can be used to advance and query a changeset
+** iterator created by this function:
+**
+**
+**
[sqlite3changeset_next()]
+**
[sqlite3changeset_op()]
+**
[sqlite3changeset_new()]
+**
[sqlite3changeset_old()]
+**
+**
+** It is the responsibility of the caller to eventually destroy the iterator
+** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
+** changeset (pChangeset) must remain valid until after the iterator is
+** destroyed.
+**
+** Assuming the changeset blob was created by one of the
+** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
+** [sqlite3changeset_invert()] functions, all changes within the changeset
+** that apply to a single table are grouped together. This means that when
+** an application iterates through a changeset using an iterator created by
+** this function, all changes that relate to a single table are visited
+** consecutively. There is no chance that the iterator will visit a change
+** the applies to table X, then one for table Y, and then later on visit
+** another change for table X.
+*/
+SQLITE_API int sqlite3changeset_start(
+ sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */
+ int nChangeset, /* Size of changeset blob in bytes */
+ void *pChangeset /* Pointer to blob containing changeset */
+);
+
+
+/*
+** CAPI3REF: Advance A Changeset Iterator
+** METHOD: sqlite3_changeset_iter
+**
+** This function may only be used with iterators created by function
+** [sqlite3changeset_start()]. If it is called on an iterator passed to
+** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
+** is returned and the call has no effect.
+**
+** Immediately after an iterator is created by sqlite3changeset_start(), it
+** does not point to any change in the changeset. Assuming the changeset
+** is not empty, the first call to this function advances the iterator to
+** point to the first change in the changeset. Each subsequent call advances
+** the iterator to point to the next change in the changeset (if any). If
+** no error occurs and the iterator points to a valid change after a call
+** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
+** Otherwise, if all changes in the changeset have already been visited,
+** SQLITE_DONE is returned.
+**
+** If an error occurs, an SQLite error code is returned. Possible error
+** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
+** SQLITE_NOMEM.
+*/
+SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
+
+/*
+** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
+** METHOD: sqlite3_changeset_iter
+**
+** The pIter argument passed to this function may either be an iterator
+** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
+** created by [sqlite3changeset_start()]. In the latter case, the most recent
+** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
+** is not the case, this function returns [SQLITE_MISUSE].
+**
+** If argument pzTab is not NULL, then *pzTab is set to point to a
+** nul-terminated utf-8 encoded string containing the name of the table
+** affected by the current change. The buffer remains valid until either
+** sqlite3changeset_next() is called on the iterator or until the
+** conflict-handler function returns. If pnCol is not NULL, then *pnCol is
+** set to the number of columns in the table affected by the change. If
+** pbIncorrect is not NULL, then *pbIndirect is set to true (1) if the change
+** is an indirect change, or false (0) otherwise. See the documentation for
+** [sqlite3session_indirect()] for a description of direct and indirect
+** changes. Finally, if pOp is not NULL, then *pOp is set to one of
+** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the
+** type of change that the iterator currently points to.
+**
+** If no error occurs, SQLITE_OK is returned. If an error does occur, an
+** SQLite error code is returned. The values of the output variables may not
+** be trusted in this case.
+*/
+SQLITE_API int sqlite3changeset_op(
+ sqlite3_changeset_iter *pIter, /* Iterator object */
+ const char **pzTab, /* OUT: Pointer to table name */
+ int *pnCol, /* OUT: Number of columns in table */
+ int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */
+ int *pbIndirect /* OUT: True for an 'indirect' change */
+);
+
+/*
+** CAPI3REF: Obtain The Primary Key Definition Of A Table
+** METHOD: sqlite3_changeset_iter
+**
+** For each modified table, a changeset includes the following:
+**
+**
+**
The number of columns in the table, and
+**
Which of those columns make up the tables PRIMARY KEY.
+**
+**
+** This function is used to find which columns comprise the PRIMARY KEY of
+** the table modified by the change that iterator pIter currently points to.
+** If successful, *pabPK is set to point to an array of nCol entries, where
+** nCol is the number of columns in the table. Elements of *pabPK are set to
+** 0x01 if the corresponding column is part of the tables primary key, or
+** 0x00 if it is not.
+**
+** If argument pnCol is not NULL, then *pnCol is set to the number of columns
+** in the table.
+**
+** If this function is called when the iterator does not point to a valid
+** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
+** SQLITE_OK is returned and the output variables populated as described
+** above.
+*/
+SQLITE_API int sqlite3changeset_pk(
+ sqlite3_changeset_iter *pIter, /* Iterator object */
+ unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */
+ int *pnCol /* OUT: Number of entries in output array */
+);
+
+/*
+** CAPI3REF: Obtain old.* Values From A Changeset Iterator
+** METHOD: sqlite3_changeset_iter
+**
+** The pIter argument passed to this function may either be an iterator
+** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
+** created by [sqlite3changeset_start()]. In the latter case, the most recent
+** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
+** Furthermore, it may only be called if the type of change that the iterator
+** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
+** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
+**
+** Argument iVal must be greater than or equal to 0, and less than the number
+** of columns in the table affected by the current change. Otherwise,
+** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
+**
+** If successful, this function sets *ppValue to point to a protected
+** sqlite3_value object containing the iVal'th value from the vector of
+** original row values stored as part of the UPDATE or DELETE change and
+** returns SQLITE_OK. The name of the function comes from the fact that this
+** is similar to the "old.*" columns available to update or delete triggers.
+**
+** If some other error occurs (e.g. an OOM condition), an SQLite error code
+** is returned and *ppValue is set to NULL.
+*/
+SQLITE_API int sqlite3changeset_old(
+ sqlite3_changeset_iter *pIter, /* Changeset iterator */
+ int iVal, /* Column number */
+ sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */
+);
+
+/*
+** CAPI3REF: Obtain new.* Values From A Changeset Iterator
+** METHOD: sqlite3_changeset_iter
+**
+** The pIter argument passed to this function may either be an iterator
+** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
+** created by [sqlite3changeset_start()]. In the latter case, the most recent
+** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
+** Furthermore, it may only be called if the type of change that the iterator
+** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
+** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
+**
+** Argument iVal must be greater than or equal to 0, and less than the number
+** of columns in the table affected by the current change. Otherwise,
+** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
+**
+** If successful, this function sets *ppValue to point to a protected
+** sqlite3_value object containing the iVal'th value from the vector of
+** new row values stored as part of the UPDATE or INSERT change and
+** returns SQLITE_OK. If the change is an UPDATE and does not include
+** a new value for the requested column, *ppValue is set to NULL and
+** SQLITE_OK returned. The name of the function comes from the fact that
+** this is similar to the "new.*" columns available to update or delete
+** triggers.
+**
+** If some other error occurs (e.g. an OOM condition), an SQLite error code
+** is returned and *ppValue is set to NULL.
+*/
+SQLITE_API int sqlite3changeset_new(
+ sqlite3_changeset_iter *pIter, /* Changeset iterator */
+ int iVal, /* Column number */
+ sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */
+);
+
+/*
+** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
+** METHOD: sqlite3_changeset_iter
+**
+** This function should only be used with iterator objects passed to a
+** conflict-handler callback by [sqlite3changeset_apply()] with either
+** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
+** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
+** is set to NULL.
+**
+** Argument iVal must be greater than or equal to 0, and less than the number
+** of columns in the table affected by the current change. Otherwise,
+** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
+**
+** If successful, this function sets *ppValue to point to a protected
+** sqlite3_value object containing the iVal'th value from the
+** "conflicting row" associated with the current conflict-handler callback
+** and returns SQLITE_OK.
+**
+** If some other error occurs (e.g. an OOM condition), an SQLite error code
+** is returned and *ppValue is set to NULL.
+*/
+SQLITE_API int sqlite3changeset_conflict(
+ sqlite3_changeset_iter *pIter, /* Changeset iterator */
+ int iVal, /* Column number */
+ sqlite3_value **ppValue /* OUT: Value from conflicting row */
+);
+
+/*
+** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
+** METHOD: sqlite3_changeset_iter
+**
+** This function may only be called with an iterator passed to an
+** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
+** it sets the output variable to the total number of known foreign key
+** violations in the destination database and returns SQLITE_OK.
+**
+** In all other cases this function returns SQLITE_MISUSE.
+*/
+SQLITE_API int sqlite3changeset_fk_conflicts(
+ sqlite3_changeset_iter *pIter, /* Changeset iterator */
+ int *pnOut /* OUT: Number of FK violations */
+);
+
+
+/*
+** CAPI3REF: Finalize A Changeset Iterator
+** METHOD: sqlite3_changeset_iter
+**
+** This function is used to finalize an iterator allocated with
+** [sqlite3changeset_start()].
+**
+** This function should only be called on iterators created using the
+** [sqlite3changeset_start()] function. If an application calls this
+** function with an iterator passed to a conflict-handler by
+** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
+** call has no effect.
+**
+** If an error was encountered within a call to an sqlite3changeset_xxx()
+** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
+** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
+** to that error is returned by this function. Otherwise, SQLITE_OK is
+** returned. This is to allow the following pattern (pseudo-code):
+**
+**
+** sqlite3changeset_start();
+** while( SQLITE_ROW==sqlite3changeset_next() ){
+** // Do something with change.
+** }
+** rc = sqlite3changeset_finalize();
+** if( rc!=SQLITE_OK ){
+** // An error has occurred
+** }
+**
+*/
+SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
+
+/*
+** CAPI3REF: Invert A Changeset
+**
+** This function is used to "invert" a changeset object. Applying an inverted
+** changeset to a database reverses the effects of applying the uninverted
+** changeset. Specifically:
+**
+**
+**
Each DELETE change is changed to an INSERT, and
+**
Each INSERT change is changed to a DELETE, and
+**
For each UPDATE change, the old.* and new.* values are exchanged.
+**
+**
+** This function does not change the order in which changes appear within
+** the changeset. It merely reverses the sense of each individual change.
+**
+** If successful, a pointer to a buffer containing the inverted changeset
+** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
+** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
+** zeroed and an SQLite error code returned.
+**
+** It is the responsibility of the caller to eventually call sqlite3_free()
+** on the *ppOut pointer to free the buffer allocation following a successful
+** call to this function.
+**
+** WARNING/TODO: This function currently assumes that the input is a valid
+** changeset. If it is not, the results are undefined.
+*/
+SQLITE_API int sqlite3changeset_invert(
+ int nIn, const void *pIn, /* Input changeset */
+ int *pnOut, void **ppOut /* OUT: Inverse of input */
+);
+
+/*
+** CAPI3REF: Concatenate Two Changeset Objects
+**
+** This function is used to concatenate two changesets, A and B, into a
+** single changeset. The result is a changeset equivalent to applying
+** changeset A followed by changeset B.
+**
+** This function combines the two input changesets using an
+** sqlite3_changegroup object. Calling it produces similar results as the
+** following code fragment:
+**
+**
+**
+** Refer to the sqlite3_changegroup documentation below for details.
+*/
+SQLITE_API int sqlite3changeset_concat(
+ int nA, /* Number of bytes in buffer pA */
+ void *pA, /* Pointer to buffer containing changeset A */
+ int nB, /* Number of bytes in buffer pB */
+ void *pB, /* Pointer to buffer containing changeset B */
+ int *pnOut, /* OUT: Number of bytes in output changeset */
+ void **ppOut /* OUT: Buffer containing output changeset */
+);
+
+
+/*
+** CAPI3REF: Changegroup Handle
+**
+** A changegroup is an object used to combine two or more
+** [changesets] or [patchsets]
+*/
+typedef struct sqlite3_changegroup sqlite3_changegroup;
+
+/*
+** CAPI3REF: Create A New Changegroup Object
+** CONSTRUCTOR: sqlite3_changegroup
+**
+** An sqlite3_changegroup object is used to combine two or more changesets
+** (or patchsets) into a single changeset (or patchset). A single changegroup
+** object may combine changesets or patchsets, but not both. The output is
+** always in the same format as the input.
+**
+** If successful, this function returns SQLITE_OK and populates (*pp) with
+** a pointer to a new sqlite3_changegroup object before returning. The caller
+** should eventually free the returned object using a call to
+** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
+** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
+**
+** The usual usage pattern for an sqlite3_changegroup object is as follows:
+**
+**
+**
It is created using a call to sqlite3changegroup_new().
+**
+**
Zero or more changesets (or patchsets) are added to the object
+** by calling sqlite3changegroup_add().
+**
+**
The result of combining all input changesets together is obtained
+** by the application via a call to sqlite3changegroup_output().
+**
+**
The object is deleted using a call to sqlite3changegroup_delete().
+**
+**
+** Any number of calls to add() and output() may be made between the calls to
+** new() and delete(), and in any order.
+**
+** As well as the regular sqlite3changegroup_add() and
+** sqlite3changegroup_output() functions, also available are the streaming
+** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
+*/
+SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
+
+/*
+** CAPI3REF: Add A Changeset To A Changegroup
+** METHOD: sqlite3_changegroup
+**
+** Add all changes within the changeset (or patchset) in buffer pData (size
+** nData bytes) to the changegroup.
+**
+** If the buffer contains a patchset, then all prior calls to this function
+** on the same changegroup object must also have specified patchsets. Or, if
+** the buffer contains a changeset, so must have the earlier calls to this
+** function. Otherwise, SQLITE_ERROR is returned and no changes are added
+** to the changegroup.
+**
+** Rows within the changeset and changegroup are identified by the values in
+** their PRIMARY KEY columns. A change in the changeset is considered to
+** apply to the same row as a change already present in the changegroup if
+** the two rows have the same primary key.
+**
+** Changes to rows that do not already appear in the changegroup are
+** simply copied into it. Or, if both the new changeset and the changegroup
+** contain changes that apply to a single row, the final contents of the
+** changegroup depends on the type of each change, as follows:
+**
+**
+**
Existing Change
+**
New Change
+**
Output Change
+**
INSERT
INSERT
+** The new change is ignored. This case does not occur if the new
+** changeset was recorded immediately after the changesets already
+** added to the changegroup.
+**
INSERT
UPDATE
+** The INSERT change remains in the changegroup. The values in the
+** INSERT change are modified as if the row was inserted by the
+** existing change and then updated according to the new change.
+**
INSERT
DELETE
+** The existing INSERT is removed from the changegroup. The DELETE is
+** not added.
+**
UPDATE
INSERT
+** The new change is ignored. This case does not occur if the new
+** changeset was recorded immediately after the changesets already
+** added to the changegroup.
+**
UPDATE
UPDATE
+** The existing UPDATE remains within the changegroup. It is amended
+** so that the accompanying values are as if the row was updated once
+** by the existing change and then again by the new change.
+**
UPDATE
DELETE
+** The existing UPDATE is replaced by the new DELETE within the
+** changegroup.
+**
DELETE
INSERT
+** If one or more of the column values in the row inserted by the
+** new change differ from those in the row deleted by the existing
+** change, the existing DELETE is replaced by an UPDATE within the
+** changegroup. Otherwise, if the inserted row is exactly the same
+** as the deleted row, the existing DELETE is simply discarded.
+**
DELETE
UPDATE
+** The new change is ignored. This case does not occur if the new
+** changeset was recorded immediately after the changesets already
+** added to the changegroup.
+**
DELETE
DELETE
+** The new change is ignored. This case does not occur if the new
+** changeset was recorded immediately after the changesets already
+** added to the changegroup.
+**
+**
+** If the new changeset contains changes to a table that is already present
+** in the changegroup, then the number of columns and the position of the
+** primary key columns for the table must be consistent. If this is not the
+** case, this function fails with SQLITE_SCHEMA. If the input changeset
+** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
+** returned. Or, if an out-of-memory condition occurs during processing, this
+** function returns SQLITE_NOMEM. In all cases, if an error occurs the
+** final contents of the changegroup is undefined.
+**
+** If no error occurs, SQLITE_OK is returned.
+*/
+SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
+
+/*
+** CAPI3REF: Obtain A Composite Changeset From A Changegroup
+** METHOD: sqlite3_changegroup
+**
+** Obtain a buffer containing a changeset (or patchset) representing the
+** current contents of the changegroup. If the inputs to the changegroup
+** were themselves changesets, the output is a changeset. Or, if the
+** inputs were patchsets, the output is also a patchset.
+**
+** As with the output of the sqlite3session_changeset() and
+** sqlite3session_patchset() functions, all changes related to a single
+** table are grouped together in the output of this function. Tables appear
+** in the same order as for the very first changeset added to the changegroup.
+** If the second or subsequent changesets added to the changegroup contain
+** changes for tables that do not appear in the first changeset, they are
+** appended onto the end of the output changeset, again in the order in
+** which they are first encountered.
+**
+** If an error occurs, an SQLite error code is returned and the output
+** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
+** is returned and the output variables are set to the size of and a
+** pointer to the output buffer, respectively. In this case it is the
+** responsibility of the caller to eventually free the buffer using a
+** call to sqlite3_free().
+*/
+SQLITE_API int sqlite3changegroup_output(
+ sqlite3_changegroup*,
+ int *pnData, /* OUT: Size of output buffer in bytes */
+ void **ppData /* OUT: Pointer to output buffer */
+);
+
+/*
+** CAPI3REF: Delete A Changegroup Object
+** DESTRUCTOR: sqlite3_changegroup
+*/
+SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
+
+/*
+** CAPI3REF: Apply A Changeset To A Database
+**
+** Apply a changeset or patchset to a database. These functions attempt to
+** update the "main" database attached to handle db with the changes found in
+** the changeset passed via the second and third arguments.
+**
+** The fourth argument (xFilter) passed to these functions is the "filter
+** callback". If it is not NULL, then for each table affected by at least one
+** change in the changeset, the filter callback is invoked with
+** the table name as the second argument, and a copy of the context pointer
+** passed as the sixth argument as the first. If the "filter callback"
+** returns zero, then no attempt is made to apply any changes to the table.
+** Otherwise, if the return value is non-zero or the xFilter argument to
+** is NULL, all changes related to the table are attempted.
+**
+** For each table that is not excluded by the filter callback, this function
+** tests that the target database contains a compatible table. A table is
+** considered compatible if all of the following are true:
+**
+**
+**
The table has the same name as the name recorded in the
+** changeset, and
+**
The table has at least as many columns as recorded in the
+** changeset, and
+**
The table has primary key columns in the same position as
+** recorded in the changeset.
+**
+**
+** If there is no compatible table, it is not an error, but none of the
+** changes associated with the table are applied. A warning message is issued
+** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
+** one such warning is issued for each table in the changeset.
+**
+** For each change for which there is a compatible table, an attempt is made
+** to modify the table contents according to the UPDATE, INSERT or DELETE
+** change. If a change cannot be applied cleanly, the conflict handler
+** function passed as the fifth argument to sqlite3changeset_apply() may be
+** invoked. A description of exactly when the conflict handler is invoked for
+** each type of change is below.
+**
+** Unlike the xFilter argument, xConflict may not be passed NULL. The results
+** of passing anything other than a valid function pointer as the xConflict
+** argument are undefined.
+**
+** Each time the conflict handler function is invoked, it must return one
+** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
+** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
+** if the second argument passed to the conflict handler is either
+** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
+** returns an illegal value, any changes already made are rolled back and
+** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
+** actions are taken by sqlite3changeset_apply() depending on the value
+** returned by each invocation of the conflict-handler function. Refer to
+** the documentation for the three
+** [SQLITE_CHANGESET_OMIT|available return values] for details.
+**
+**
+**
DELETE Changes
+** For each DELETE change, the function checks if the target database
+** contains a row with the same primary key value (or values) as the
+** original row values stored in the changeset. If it does, and the values
+** stored in all non-primary key columns also match the values stored in
+** the changeset the row is deleted from the target database.
+**
+** If a row with matching primary key values is found, but one or more of
+** the non-primary key fields contains a value different from the original
+** row value stored in the changeset, the conflict-handler function is
+** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
+** database table has more columns than are recorded in the changeset,
+** only the values of those non-primary key fields are compared against
+** the current database contents - any trailing database table columns
+** are ignored.
+**
+** If no row with matching primary key values is found in the database,
+** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
+** passed as the second argument.
+**
+** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
+** (which can only happen if a foreign key constraint is violated), the
+** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
+** passed as the second argument. This includes the case where the DELETE
+** operation is attempted because an earlier call to the conflict handler
+** function returned [SQLITE_CHANGESET_REPLACE].
+**
+**
INSERT Changes
+** For each INSERT change, an attempt is made to insert the new row into
+** the database. If the changeset row contains fewer fields than the
+** database table, the trailing fields are populated with their default
+** values.
+**
+** If the attempt to insert the row fails because the database already
+** contains a row with the same primary key values, the conflict handler
+** function is invoked with the second argument set to
+** [SQLITE_CHANGESET_CONFLICT].
+**
+** If the attempt to insert the row fails because of some other constraint
+** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
+** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
+** This includes the case where the INSERT operation is re-attempted because
+** an earlier call to the conflict handler function returned
+** [SQLITE_CHANGESET_REPLACE].
+**
+**
UPDATE Changes
+** For each UPDATE change, the function checks if the target database
+** contains a row with the same primary key value (or values) as the
+** original row values stored in the changeset. If it does, and the values
+** stored in all modified non-primary key columns also match the values
+** stored in the changeset the row is updated within the target database.
+**
+** If a row with matching primary key values is found, but one or more of
+** the modified non-primary key fields contains a value different from an
+** original row value stored in the changeset, the conflict-handler function
+** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
+** UPDATE changes only contain values for non-primary key fields that are
+** to be modified, only those fields need to match the original values to
+** avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
+**
+** If no row with matching primary key values is found in the database,
+** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
+** passed as the second argument.
+**
+** If the UPDATE operation is attempted, but SQLite returns
+** SQLITE_CONSTRAINT, the conflict-handler function is invoked with
+** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
+** This includes the case where the UPDATE operation is attempted after
+** an earlier call to the conflict handler function returned
+** [SQLITE_CHANGESET_REPLACE].
+**
+**
+** It is safe to execute SQL statements, including those that write to the
+** table that the callback related to, from within the xConflict callback.
+** This can be used to further customize the applications conflict
+** resolution strategy.
+**
+** All changes made by these functions are enclosed in a savepoint transaction.
+** If any other error (aside from a constraint failure when attempting to
+** write to the target database) occurs, then the savepoint transaction is
+** rolled back, restoring the target database to its original state, and an
+** SQLite error code returned.
+**
+** If the output parameters (ppRebase) and (pnRebase) are non-NULL and
+** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2()
+** may set (*ppRebase) to point to a "rebase" that may be used with the
+** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase)
+** is set to the size of the buffer in bytes. It is the responsibility of the
+** caller to eventually free any such buffer using sqlite3_free(). The buffer
+** is only allocated and populated if one or more conflicts were encountered
+** while applying the patchset. See comments surrounding the sqlite3_rebaser
+** APIs for further details.
+**
+** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent
+** may be modified by passing a combination of
+** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter.
+**
+** Note that the sqlite3changeset_apply_v2() API is still experimental
+** and therefore subject to change.
+*/
+SQLITE_API int sqlite3changeset_apply(
+ sqlite3 *db, /* Apply change to "main" db of this handle */
+ int nChangeset, /* Size of changeset in bytes */
+ void *pChangeset, /* Changeset blob */
+ int(*xFilter)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ const char *zTab /* Table name */
+ ),
+ int(*xConflict)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
+ sqlite3_changeset_iter *p /* Handle describing change and conflict */
+ ),
+ void *pCtx /* First argument passed to xConflict */
+);
+SQLITE_API int sqlite3changeset_apply_v2(
+ sqlite3 *db, /* Apply change to "main" db of this handle */
+ int nChangeset, /* Size of changeset in bytes */
+ void *pChangeset, /* Changeset blob */
+ int(*xFilter)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ const char *zTab /* Table name */
+ ),
+ int(*xConflict)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
+ sqlite3_changeset_iter *p /* Handle describing change and conflict */
+ ),
+ void *pCtx, /* First argument passed to xConflict */
+ void **ppRebase, int *pnRebase, /* OUT: Rebase data */
+ int flags /* Combination of SESSION_APPLY_* flags */
+);
+
+/*
+** CAPI3REF: Flags for sqlite3changeset_apply_v2
+**
+** The following flags may passed via the 9th parameter to
+** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]:
+**
+**
+**
SQLITE_CHANGESETAPPLY_NOSAVEPOINT
+** Usually, the sessions module encloses all operations performed by
+** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The
+** SAVEPOINT is committed if the changeset or patchset is successfully
+** applied, or rolled back if an error occurs. Specifying this flag
+** causes the sessions module to omit this savepoint. In this case, if the
+** caller has an open transaction or savepoint when apply_v2() is called,
+** it may revert the partially applied changeset by rolling it back.
+*/
+#define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001
+
+/*
+** CAPI3REF: Constants Passed To The Conflict Handler
+**
+** Values that may be passed as the second argument to a conflict-handler.
+**
+**
+**
SQLITE_CHANGESET_DATA
+** The conflict handler is invoked with CHANGESET_DATA as the second argument
+** when processing a DELETE or UPDATE change if a row with the required
+** PRIMARY KEY fields is present in the database, but one or more other
+** (non primary-key) fields modified by the update do not contain the
+** expected "before" values.
+**
+** The conflicting row, in this case, is the database row with the matching
+** primary key.
+**
+**
SQLITE_CHANGESET_NOTFOUND
+** The conflict handler is invoked with CHANGESET_NOTFOUND as the second
+** argument when processing a DELETE or UPDATE change if a row with the
+** required PRIMARY KEY fields is not present in the database.
+**
+** There is no conflicting row in this case. The results of invoking the
+** sqlite3changeset_conflict() API are undefined.
+**
+**
SQLITE_CHANGESET_CONFLICT
+** CHANGESET_CONFLICT is passed as the second argument to the conflict
+** handler while processing an INSERT change if the operation would result
+** in duplicate primary key values.
+**
+** The conflicting row in this case is the database row with the matching
+** primary key.
+**
+**
SQLITE_CHANGESET_FOREIGN_KEY
+** If foreign key handling is enabled, and applying a changeset leaves the
+** database in a state containing foreign key violations, the conflict
+** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
+** exactly once before the changeset is committed. If the conflict handler
+** returns CHANGESET_OMIT, the changes, including those that caused the
+** foreign key constraint violation, are committed. Or, if it returns
+** CHANGESET_ABORT, the changeset is rolled back.
+**
+** No current or conflicting row information is provided. The only function
+** it is possible to call on the supplied sqlite3_changeset_iter handle
+** is sqlite3changeset_fk_conflicts().
+**
+**
SQLITE_CHANGESET_CONSTRAINT
+** If any other constraint violation occurs while applying a change (i.e.
+** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
+** invoked with CHANGESET_CONSTRAINT as the second argument.
+**
+** There is no conflicting row in this case. The results of invoking the
+** sqlite3changeset_conflict() API are undefined.
+**
+**
+*/
+#define SQLITE_CHANGESET_DATA 1
+#define SQLITE_CHANGESET_NOTFOUND 2
+#define SQLITE_CHANGESET_CONFLICT 3
+#define SQLITE_CHANGESET_CONSTRAINT 4
+#define SQLITE_CHANGESET_FOREIGN_KEY 5
+
+/*
+** CAPI3REF: Constants Returned By The Conflict Handler
+**
+** A conflict handler callback must return one of the following three values.
+**
+**
+**
SQLITE_CHANGESET_OMIT
+** If a conflict handler returns this value no special action is taken. The
+** change that caused the conflict is not applied. The session module
+** continues to the next change in the changeset.
+**
+**
SQLITE_CHANGESET_REPLACE
+** This value may only be returned if the second argument to the conflict
+** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
+** is not the case, any changes applied so far are rolled back and the
+** call to sqlite3changeset_apply() returns SQLITE_MISUSE.
+**
+** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
+** handler, then the conflicting row is either updated or deleted, depending
+** on the type of change.
+**
+** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
+** handler, then the conflicting row is removed from the database and a
+** second attempt to apply the change is made. If this second attempt fails,
+** the original row is restored to the database before continuing.
+**
+**
SQLITE_CHANGESET_ABORT
+** If this value is returned, any changes applied so far are rolled back
+** and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
+**
+*/
+#define SQLITE_CHANGESET_OMIT 0
+#define SQLITE_CHANGESET_REPLACE 1
+#define SQLITE_CHANGESET_ABORT 2
+
+/*
+** CAPI3REF: Rebasing changesets
+** EXPERIMENTAL
+**
+** Suppose there is a site hosting a database in state S0. And that
+** modifications are made that move that database to state S1 and a
+** changeset recorded (the "local" changeset). Then, a changeset based
+** on S0 is received from another site (the "remote" changeset) and
+** applied to the database. The database is then in state
+** (S1+"remote"), where the exact state depends on any conflict
+** resolution decisions (OMIT or REPLACE) made while applying "remote".
+** Rebasing a changeset is to update it to take those conflict
+** resolution decisions into account, so that the same conflicts
+** do not have to be resolved elsewhere in the network.
+**
+** For example, if both the local and remote changesets contain an
+** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)":
+**
+** local: INSERT INTO t1 VALUES(1, 'v1');
+** remote: INSERT INTO t1 VALUES(1, 'v2');
+**
+** and the conflict resolution is REPLACE, then the INSERT change is
+** removed from the local changeset (it was overridden). Or, if the
+** conflict resolution was "OMIT", then the local changeset is modified
+** to instead contain:
+**
+** UPDATE t1 SET b = 'v2' WHERE a=1;
+**
+** Changes within the local changeset are rebased as follows:
+**
+**
+**
Local INSERT
+** This may only conflict with a remote INSERT. If the conflict
+** resolution was OMIT, then add an UPDATE change to the rebased
+** changeset. Or, if the conflict resolution was REPLACE, add
+** nothing to the rebased changeset.
+**
+**
Local DELETE
+** This may conflict with a remote UPDATE or DELETE. In both cases the
+** only possible resolution is OMIT. If the remote operation was a
+** DELETE, then add no change to the rebased changeset. If the remote
+** operation was an UPDATE, then the old.* fields of change are updated
+** to reflect the new.* values in the UPDATE.
+**
+**
Local UPDATE
+** This may conflict with a remote UPDATE or DELETE. If it conflicts
+** with a DELETE, and the conflict resolution was OMIT, then the update
+** is changed into an INSERT. Any undefined values in the new.* record
+** from the update change are filled in using the old.* values from
+** the conflicting DELETE. Or, if the conflict resolution was REPLACE,
+** the UPDATE change is simply omitted from the rebased changeset.
+**
+** If conflict is with a remote UPDATE and the resolution is OMIT, then
+** the old.* values are rebased using the new.* values in the remote
+** change. Or, if the resolution is REPLACE, then the change is copied
+** into the rebased changeset with updates to columns also updated by
+** the conflicting remote UPDATE removed. If this means no columns would
+** be updated, the change is omitted.
+**
+**
+** A local change may be rebased against multiple remote changes
+** simultaneously. If a single key is modified by multiple remote
+** changesets, they are combined as follows before the local changeset
+** is rebased:
+**
+**
+**
If there has been one or more REPLACE resolutions on a
+** key, it is rebased according to a REPLACE.
+**
+**
If there have been no REPLACE resolutions on a key, then
+** the local changeset is rebased according to the most recent
+** of the OMIT resolutions.
+**
+**
+** Note that conflict resolutions from multiple remote changesets are
+** combined on a per-field basis, not per-row. This means that in the
+** case of multiple remote UPDATE operations, some fields of a single
+** local change may be rebased for REPLACE while others are rebased for
+** OMIT.
+**
+** In order to rebase a local changeset, the remote changeset must first
+** be applied to the local database using sqlite3changeset_apply_v2() and
+** the buffer of rebase information captured. Then:
+**
+**
+**
An sqlite3_rebaser object is created by calling
+** sqlite3rebaser_create().
+**
The new object is configured with the rebase buffer obtained from
+** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure().
+** If the local changeset is to be rebased against multiple remote
+** changesets, then sqlite3rebaser_configure() should be called
+** multiple times, in the same order that the multiple
+** sqlite3changeset_apply_v2() calls were made.
+**
Each local changeset is rebased by calling sqlite3rebaser_rebase().
+**
The sqlite3_rebaser object is deleted by calling
+** sqlite3rebaser_delete().
+**
+*/
+typedef struct sqlite3_rebaser sqlite3_rebaser;
+
+/*
+** CAPI3REF: Create a changeset rebaser object.
+** EXPERIMENTAL
+**
+** Allocate a new changeset rebaser object. If successful, set (*ppNew) to
+** point to the new object and return SQLITE_OK. Otherwise, if an error
+** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew)
+** to NULL.
+*/
+SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew);
+
+/*
+** CAPI3REF: Configure a changeset rebaser object.
+** EXPERIMENTAL
+**
+** Configure the changeset rebaser object to rebase changesets according
+** to the conflict resolutions described by buffer pRebase (size nRebase
+** bytes), which must have been obtained from a previous call to
+** sqlite3changeset_apply_v2().
+*/
+SQLITE_API int sqlite3rebaser_configure(
+ sqlite3_rebaser*,
+ int nRebase, const void *pRebase
+);
+
+/*
+** CAPI3REF: Rebase a changeset
+** EXPERIMENTAL
+**
+** Argument pIn must point to a buffer containing a changeset nIn bytes
+** in size. This function allocates and populates a buffer with a copy
+** of the changeset rebased rebased according to the configuration of the
+** rebaser object passed as the first argument. If successful, (*ppOut)
+** is set to point to the new buffer containing the rebased changset and
+** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the
+** responsibility of the caller to eventually free the new buffer using
+** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut)
+** are set to zero and an SQLite error code returned.
+*/
+SQLITE_API int sqlite3rebaser_rebase(
+ sqlite3_rebaser*,
+ int nIn, const void *pIn,
+ int *pnOut, void **ppOut
+);
+
+/*
+** CAPI3REF: Delete a changeset rebaser object.
+** EXPERIMENTAL
+**
+** Delete the changeset rebaser object and all associated resources. There
+** should be one call to this function for each successful invocation
+** of sqlite3rebaser_create().
+*/
+SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p);
+
+/*
+** CAPI3REF: Streaming Versions of API functions.
+**
+** The six streaming API xxx_strm() functions serve similar purposes to the
+** corresponding non-streaming API functions:
+**
+**
+**
Streaming function
Non-streaming equivalent
+**
sqlite3changeset_apply_strm
[sqlite3changeset_apply]
+**
sqlite3changeset_apply_strm_v2
[sqlite3changeset_apply_v2]
+**
sqlite3changeset_concat_strm
[sqlite3changeset_concat]
+**
sqlite3changeset_invert_strm
[sqlite3changeset_invert]
+**
sqlite3changeset_start_strm
[sqlite3changeset_start]
+**
sqlite3session_changeset_strm
[sqlite3session_changeset]
+**
sqlite3session_patchset_strm
[sqlite3session_patchset]
+**
+**
+** Non-streaming functions that accept changesets (or patchsets) as input
+** require that the entire changeset be stored in a single buffer in memory.
+** Similarly, those that return a changeset or patchset do so by returning
+** a pointer to a single large buffer allocated using sqlite3_malloc().
+** Normally this is convenient. However, if an application running in a
+** low-memory environment is required to handle very large changesets, the
+** large contiguous memory allocations required can become onerous.
+**
+** In order to avoid this problem, instead of a single large buffer, input
+** is passed to a streaming API functions by way of a callback function that
+** the sessions module invokes to incrementally request input data as it is
+** required. In all cases, a pair of API function parameters such as
+**
+**
+** int nChangeset,
+** void *pChangeset,
+**
+**
+** Is replaced by:
+**
+**
+** int (*xInput)(void *pIn, void *pData, int *pnData),
+** void *pIn,
+**
+**
+** Each time the xInput callback is invoked by the sessions module, the first
+** argument passed is a copy of the supplied pIn context pointer. The second
+** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
+** error occurs the xInput method should copy up to (*pnData) bytes of data
+** into the buffer and set (*pnData) to the actual number of bytes copied
+** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
+** should be set to zero to indicate this. Or, if an error occurs, an SQLite
+** error code should be returned. In all cases, if an xInput callback returns
+** an error, all processing is abandoned and the streaming API function
+** returns a copy of the error code to the caller.
+**
+** In the case of sqlite3changeset_start_strm(), the xInput callback may be
+** invoked by the sessions module at any point during the lifetime of the
+** iterator. If such an xInput callback returns an error, the iterator enters
+** an error state, whereby all subsequent calls to iterator functions
+** immediately fail with the same error code as returned by xInput.
+**
+** Similarly, streaming API functions that return changesets (or patchsets)
+** return them in chunks by way of a callback function instead of via a
+** pointer to a single large buffer. In this case, a pair of parameters such
+** as:
+**
+**
+** int *pnChangeset,
+** void **ppChangeset,
+**
+**
+** Is replaced by:
+**
+**
+** int (*xOutput)(void *pOut, const void *pData, int nData),
+** void *pOut
+**
+**
+** The xOutput callback is invoked zero or more times to return data to
+** the application. The first parameter passed to each call is a copy of the
+** pOut pointer supplied by the application. The second parameter, pData,
+** points to a buffer nData bytes in size containing the chunk of output
+** data being returned. If the xOutput callback successfully processes the
+** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
+** it should return some other SQLite error code. In this case processing
+** is immediately abandoned and the streaming API function returns a copy
+** of the xOutput error code to the application.
+**
+** The sessions module never invokes an xOutput callback with the third
+** parameter set to a value less than or equal to zero. Other than this,
+** no guarantees are made as to the size of the chunks of data returned.
+*/
+SQLITE_API int sqlite3changeset_apply_strm(
+ sqlite3 *db, /* Apply change to "main" db of this handle */
+ int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
+ void *pIn, /* First arg for xInput */
+ int(*xFilter)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ const char *zTab /* Table name */
+ ),
+ int(*xConflict)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
+ sqlite3_changeset_iter *p /* Handle describing change and conflict */
+ ),
+ void *pCtx /* First argument passed to xConflict */
+);
+SQLITE_API int sqlite3changeset_apply_v2_strm(
+ sqlite3 *db, /* Apply change to "main" db of this handle */
+ int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
+ void *pIn, /* First arg for xInput */
+ int(*xFilter)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ const char *zTab /* Table name */
+ ),
+ int(*xConflict)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
+ sqlite3_changeset_iter *p /* Handle describing change and conflict */
+ ),
+ void *pCtx, /* First argument passed to xConflict */
+ void **ppRebase, int *pnRebase,
+ int flags
+);
+SQLITE_API int sqlite3changeset_concat_strm(
+ int (*xInputA)(void *pIn, void *pData, int *pnData),
+ void *pInA,
+ int (*xInputB)(void *pIn, void *pData, int *pnData),
+ void *pInB,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3changeset_invert_strm(
+ int (*xInput)(void *pIn, void *pData, int *pnData),
+ void *pIn,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3changeset_start_strm(
+ sqlite3_changeset_iter **pp,
+ int (*xInput)(void *pIn, void *pData, int *pnData),
+ void *pIn
+);
+SQLITE_API int sqlite3session_changeset_strm(
+ sqlite3_session *pSession,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3session_patchset_strm(
+ sqlite3_session *pSession,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
+ int (*xInput)(void *pIn, void *pData, int *pnData),
+ void *pIn
+);
+SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3rebaser_rebase_strm(
+ sqlite3_rebaser *pRebaser,
+ int (*xInput)(void *pIn, void *pData, int *pnData),
+ void *pIn,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+
+
+/*
+** Make sure we can call this stuff from C++.
+*/
+#if 0
+}
+#endif
+
+#endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
+
+/******** End of sqlite3session.h *********/
+/******** Begin file fts5.h *********/
+/*
+** 2014 May 31
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** Interfaces to extend FTS5. Using the interfaces defined in this file,
+** FTS5 may be extended with:
+**
+** * custom tokenizers, and
+** * custom auxiliary functions.
+*/
+
+
+#ifndef _FTS5_H
+#define _FTS5_H
+
+
+#if 0
+extern "C" {
+#endif
+
+/*************************************************************************
+** CUSTOM AUXILIARY FUNCTIONS
+**
+** Virtual table implementations may overload SQL functions by implementing
+** the sqlite3_module.xFindFunction() method.
+*/
+
+typedef struct Fts5ExtensionApi Fts5ExtensionApi;
+typedef struct Fts5Context Fts5Context;
+typedef struct Fts5PhraseIter Fts5PhraseIter;
+
+typedef void (*fts5_extension_function)(
+ const Fts5ExtensionApi *pApi, /* API offered by current FTS version */
+ Fts5Context *pFts, /* First arg to pass to pApi functions */
+ sqlite3_context *pCtx, /* Context for returning result/error */
+ int nVal, /* Number of values in apVal[] array */
+ sqlite3_value **apVal /* Array of trailing arguments */
+);
+
+struct Fts5PhraseIter {
+ const unsigned char *a;
+ const unsigned char *b;
+};
+
+/*
+** EXTENSION API FUNCTIONS
+**
+** xUserData(pFts):
+** Return a copy of the context pointer the extension function was
+** registered with.
+**
+** xColumnTotalSize(pFts, iCol, pnToken):
+** If parameter iCol is less than zero, set output variable *pnToken
+** to the total number of tokens in the FTS5 table. Or, if iCol is
+** non-negative but less than the number of columns in the table, return
+** the total number of tokens in column iCol, considering all rows in
+** the FTS5 table.
+**
+** If parameter iCol is greater than or equal to the number of columns
+** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
+** an OOM condition or IO error), an appropriate SQLite error code is
+** returned.
+**
+** xColumnCount(pFts):
+** Return the number of columns in the table.
+**
+** xColumnSize(pFts, iCol, pnToken):
+** If parameter iCol is less than zero, set output variable *pnToken
+** to the total number of tokens in the current row. Or, if iCol is
+** non-negative but less than the number of columns in the table, set
+** *pnToken to the number of tokens in column iCol of the current row.
+**
+** If parameter iCol is greater than or equal to the number of columns
+** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
+** an OOM condition or IO error), an appropriate SQLite error code is
+** returned.
+**
+** This function may be quite inefficient if used with an FTS5 table
+** created with the "columnsize=0" option.
+**
+** xColumnText:
+** This function attempts to retrieve the text of column iCol of the
+** current document. If successful, (*pz) is set to point to a buffer
+** containing the text in utf-8 encoding, (*pn) is set to the size in bytes
+** (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
+** if an error occurs, an SQLite error code is returned and the final values
+** of (*pz) and (*pn) are undefined.
+**
+** xPhraseCount:
+** Returns the number of phrases in the current query expression.
+**
+** xPhraseSize:
+** Returns the number of tokens in phrase iPhrase of the query. Phrases
+** are numbered starting from zero.
+**
+** xInstCount:
+** Set *pnInst to the total number of occurrences of all phrases within
+** the query within the current row. Return SQLITE_OK if successful, or
+** an error code (i.e. SQLITE_NOMEM) if an error occurs.
+**
+** This API can be quite slow if used with an FTS5 table created with the
+** "detail=none" or "detail=column" option. If the FTS5 table is created
+** with either "detail=none" or "detail=column" and "content=" option
+** (i.e. if it is a contentless table), then this API always returns 0.
+**
+** xInst:
+** Query for the details of phrase match iIdx within the current row.
+** Phrase matches are numbered starting from zero, so the iIdx argument
+** should be greater than or equal to zero and smaller than the value
+** output by xInstCount().
+**
+** Usually, output parameter *piPhrase is set to the phrase number, *piCol
+** to the column in which it occurs and *piOff the token offset of the
+** first token of the phrase. The exception is if the table was created
+** with the offsets=0 option specified. In this case *piOff is always
+** set to -1.
+**
+** Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM)
+** if an error occurs.
+**
+** This API can be quite slow if used with an FTS5 table created with the
+** "detail=none" or "detail=column" option.
+**
+** xRowid:
+** Returns the rowid of the current row.
+**
+** xTokenize:
+** Tokenize text using the tokenizer belonging to the FTS5 table.
+**
+** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
+** This API function is used to query the FTS table for phrase iPhrase
+** of the current query. Specifically, a query equivalent to:
+**
+** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
+**
+** with $p set to a phrase equivalent to the phrase iPhrase of the
+** current query is executed. Any column filter that applies to
+** phrase iPhrase of the current query is included in $p. For each
+** row visited, the callback function passed as the fourth argument
+** is invoked. The context and API objects passed to the callback
+** function may be used to access the properties of each matched row.
+** Invoking Api.xUserData() returns a copy of the pointer passed as
+** the third argument to pUserData.
+**
+** If the callback function returns any value other than SQLITE_OK, the
+** query is abandoned and the xQueryPhrase function returns immediately.
+** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
+** Otherwise, the error code is propagated upwards.
+**
+** If the query runs to completion without incident, SQLITE_OK is returned.
+** Or, if some error occurs before the query completes or is aborted by
+** the callback, an SQLite error code is returned.
+**
+**
+** xSetAuxdata(pFts5, pAux, xDelete)
+**
+** Save the pointer passed as the second argument as the extension functions
+** "auxiliary data". The pointer may then be retrieved by the current or any
+** future invocation of the same fts5 extension function made as part of
+** of the same MATCH query using the xGetAuxdata() API.
+**
+** Each extension function is allocated a single auxiliary data slot for
+** each FTS query (MATCH expression). If the extension function is invoked
+** more than once for a single FTS query, then all invocations share a
+** single auxiliary data context.
+**
+** If there is already an auxiliary data pointer when this function is
+** invoked, then it is replaced by the new pointer. If an xDelete callback
+** was specified along with the original pointer, it is invoked at this
+** point.
+**
+** The xDelete callback, if one is specified, is also invoked on the
+** auxiliary data pointer after the FTS5 query has finished.
+**
+** If an error (e.g. an OOM condition) occurs within this function, an
+** the auxiliary data is set to NULL and an error code returned. If the
+** xDelete parameter was not NULL, it is invoked on the auxiliary data
+** pointer before returning.
+**
+**
+** xGetAuxdata(pFts5, bClear)
+**
+** Returns the current auxiliary data pointer for the fts5 extension
+** function. See the xSetAuxdata() method for details.
+**
+** If the bClear argument is non-zero, then the auxiliary data is cleared
+** (set to NULL) before this function returns. In this case the xDelete,
+** if any, is not invoked.
+**
+**
+** xRowCount(pFts5, pnRow)
+**
+** This function is used to retrieve the total number of rows in the table.
+** In other words, the same value that would be returned by:
+**
+** SELECT count(*) FROM ftstable;
+**
+** xPhraseFirst()
+** This function is used, along with type Fts5PhraseIter and the xPhraseNext
+** method, to iterate through all instances of a single query phrase within
+** the current row. This is the same information as is accessible via the
+** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
+** to use, this API may be faster under some circumstances. To iterate
+** through instances of phrase iPhrase, use the following code:
+**
+** Fts5PhraseIter iter;
+** int iCol, iOff;
+** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
+** iCol>=0;
+** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
+** ){
+** // An instance of phrase iPhrase at offset iOff of column iCol
+** }
+**
+** The Fts5PhraseIter structure is defined above. Applications should not
+** modify this structure directly - it should only be used as shown above
+** with the xPhraseFirst() and xPhraseNext() API methods (and by
+** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
+**
+** This API can be quite slow if used with an FTS5 table created with the
+** "detail=none" or "detail=column" option. If the FTS5 table is created
+** with either "detail=none" or "detail=column" and "content=" option
+** (i.e. if it is a contentless table), then this API always iterates
+** through an empty set (all calls to xPhraseFirst() set iCol to -1).
+**
+** xPhraseNext()
+** See xPhraseFirst above.
+**
+** xPhraseFirstColumn()
+** This function and xPhraseNextColumn() are similar to the xPhraseFirst()
+** and xPhraseNext() APIs described above. The difference is that instead
+** of iterating through all instances of a phrase in the current row, these
+** APIs are used to iterate through the set of columns in the current row
+** that contain one or more instances of a specified phrase. For example:
+**
+** Fts5PhraseIter iter;
+** int iCol;
+** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
+** iCol>=0;
+** pApi->xPhraseNextColumn(pFts, &iter, &iCol)
+** ){
+** // Column iCol contains at least one instance of phrase iPhrase
+** }
+**
+** This API can be quite slow if used with an FTS5 table created with the
+** "detail=none" option. If the FTS5 table is created with either
+** "detail=none" "content=" option (i.e. if it is a contentless table),
+** then this API always iterates through an empty set (all calls to
+** xPhraseFirstColumn() set iCol to -1).
+**
+** The information accessed using this API and its companion
+** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
+** (or xInst/xInstCount). The chief advantage of this API is that it is
+** significantly more efficient than those alternatives when used with
+** "detail=column" tables.
+**
+** xPhraseNextColumn()
+** See xPhraseFirstColumn above.
+*/
+struct Fts5ExtensionApi {
+ int iVersion; /* Currently always set to 3 */
+
+ void *(*xUserData)(Fts5Context*);
+
+ int (*xColumnCount)(Fts5Context*);
+ int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
+ int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
+
+ int (*xTokenize)(Fts5Context*,
+ const char *pText, int nText, /* Text to tokenize */
+ void *pCtx, /* Context passed to xToken() */
+ int (*xToken)(void*, int, const char*, int, int, int) /* Callback */
+ );
+
+ int (*xPhraseCount)(Fts5Context*);
+ int (*xPhraseSize)(Fts5Context*, int iPhrase);
+
+ int (*xInstCount)(Fts5Context*, int *pnInst);
+ int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
+
+ sqlite3_int64 (*xRowid)(Fts5Context*);
+ int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
+ int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
+
+ int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
+ int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
+ );
+ int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
+ void *(*xGetAuxdata)(Fts5Context*, int bClear);
+
+ int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
+ void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
+
+ int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
+ void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
+};
+
+/*
+** CUSTOM AUXILIARY FUNCTIONS
+*************************************************************************/
+
+/*************************************************************************
+** CUSTOM TOKENIZERS
+**
+** Applications may also register custom tokenizer types. A tokenizer
+** is registered by providing fts5 with a populated instance of the
+** following structure. All structure methods must be defined, setting
+** any member of the fts5_tokenizer struct to NULL leads to undefined
+** behaviour. The structure methods are expected to function as follows:
+**
+** xCreate:
+** This function is used to allocate and initialize a tokenizer instance.
+** A tokenizer instance is required to actually tokenize text.
+**
+** The first argument passed to this function is a copy of the (void*)
+** pointer provided by the application when the fts5_tokenizer object
+** was registered with FTS5 (the third argument to xCreateTokenizer()).
+** The second and third arguments are an array of nul-terminated strings
+** containing the tokenizer arguments, if any, specified following the
+** tokenizer name as part of the CREATE VIRTUAL TABLE statement used
+** to create the FTS5 table.
+**
+** The final argument is an output variable. If successful, (*ppOut)
+** should be set to point to the new tokenizer handle and SQLITE_OK
+** returned. If an error occurs, some value other than SQLITE_OK should
+** be returned. In this case, fts5 assumes that the final value of *ppOut
+** is undefined.
+**
+** xDelete:
+** This function is invoked to delete a tokenizer handle previously
+** allocated using xCreate(). Fts5 guarantees that this function will
+** be invoked exactly once for each successful call to xCreate().
+**
+** xTokenize:
+** This function is expected to tokenize the nText byte string indicated
+** by argument pText. pText may or may not be nul-terminated. The first
+** argument passed to this function is a pointer to an Fts5Tokenizer object
+** returned by an earlier call to xCreate().
+**
+** The second argument indicates the reason that FTS5 is requesting
+** tokenization of the supplied text. This is always one of the following
+** four values:
+**
+**
FTS5_TOKENIZE_DOCUMENT - A document is being inserted into
+** or removed from the FTS table. The tokenizer is being invoked to
+** determine the set of tokens to add to (or delete from) the
+** FTS index.
+**
+**
FTS5_TOKENIZE_QUERY - A MATCH query is being executed
+** against the FTS index. The tokenizer is being called to tokenize
+** a bareword or quoted string specified as part of the query.
+**
+**
(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX) - Same as
+** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
+** followed by a "*" character, indicating that the last token
+** returned by the tokenizer will be treated as a token prefix.
+**
+**
FTS5_TOKENIZE_AUX - The tokenizer is being invoked to
+** satisfy an fts5_api.xTokenize() request made by an auxiliary
+** function. Or an fts5_api.xColumnSize() request made by the same
+** on a columnsize=0 database.
+**
+**
+** For each token in the input string, the supplied callback xToken() must
+** be invoked. The first argument to it should be a copy of the pointer
+** passed as the second argument to xTokenize(). The third and fourth
+** arguments are a pointer to a buffer containing the token text, and the
+** size of the token in bytes. The 4th and 5th arguments are the byte offsets
+** of the first byte of and first byte immediately following the text from
+** which the token is derived within the input.
+**
+** The second argument passed to the xToken() callback ("tflags") should
+** normally be set to 0. The exception is if the tokenizer supports
+** synonyms. In this case see the discussion below for details.
+**
+** FTS5 assumes the xToken() callback is invoked for each token in the
+** order that they occur within the input text.
+**
+** If an xToken() callback returns any value other than SQLITE_OK, then
+** the tokenization should be abandoned and the xTokenize() method should
+** immediately return a copy of the xToken() return value. Or, if the
+** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
+** if an error occurs with the xTokenize() implementation itself, it
+** may abandon the tokenization and return any error code other than
+** SQLITE_OK or SQLITE_DONE.
+**
+** SYNONYM SUPPORT
+**
+** Custom tokenizers may also support synonyms. Consider a case in which a
+** user wishes to query for a phrase such as "first place". Using the
+** built-in tokenizers, the FTS5 query 'first + place' will match instances
+** of "first place" within the document set, but not alternative forms
+** such as "1st place". In some applications, it would be better to match
+** all instances of "first place" or "1st place" regardless of which form
+** the user specified in the MATCH query text.
+**
+** There are several ways to approach this in FTS5:
+**
+**
By mapping all synonyms to a single token. In this case, the
+** In the above example, this means that the tokenizer returns the
+** same token for inputs "first" and "1st". Say that token is in
+** fact "first", so that when the user inserts the document "I won
+** 1st place" entries are added to the index for tokens "i", "won",
+** "first" and "place". If the user then queries for '1st + place',
+** the tokenizer substitutes "first" for "1st" and the query works
+** as expected.
+**
+**
By adding multiple synonyms for a single term to the FTS index.
+** In this case, when tokenizing query text, the tokenizer may
+** provide multiple synonyms for a single term within the document.
+** FTS5 then queries the index for each synonym individually. For
+** example, faced with the query:
+**
+**
+** ... MATCH 'first place'
+**
+** the tokenizer offers both "1st" and "first" as synonyms for the
+** first token in the MATCH query and FTS5 effectively runs a query
+** similar to:
+**
+**
+** ... MATCH '(first OR 1st) place'
+**
+** except that, for the purposes of auxiliary functions, the query
+** still appears to contain just two phrases - "(first OR 1st)"
+** being treated as a single phrase.
+**
+**
By adding multiple synonyms for a single term to the FTS index.
+** Using this method, when tokenizing document text, the tokenizer
+** provides multiple synonyms for each token. So that when a
+** document such as "I won first place" is tokenized, entries are
+** added to the FTS index for "i", "won", "first", "1st" and
+** "place".
+**
+** This way, even if the tokenizer does not provide synonyms
+** when tokenizing query text (it should not - to do would be
+** inefficient), it doesn't matter if the user queries for
+** 'first + place' or '1st + place', as there are entries in the
+** FTS index corresponding to both forms of the first token.
+**
+**
+** Whether it is parsing document or query text, any call to xToken that
+** specifies a tflags argument with the FTS5_TOKEN_COLOCATED bit
+** is considered to supply a synonym for the previous token. For example,
+** when parsing the document "I won first place", a tokenizer that supports
+** synonyms would call xToken() 5 times, as follows:
+**
+**
+** xToken(pCtx, 0, "i", 1, 0, 1);
+** xToken(pCtx, 0, "won", 3, 2, 5);
+** xToken(pCtx, 0, "first", 5, 6, 11);
+** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11);
+** xToken(pCtx, 0, "place", 5, 12, 17);
+**
+**
+** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
+** xToken() is called. Multiple synonyms may be specified for a single token
+** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
+** There is no limit to the number of synonyms that may be provided for a
+** single token.
+**
+** In many cases, method (1) above is the best approach. It does not add
+** extra data to the FTS index or require FTS5 to query for multiple terms,
+** so it is efficient in terms of disk space and query speed. However, it
+** does not support prefix queries very well. If, as suggested above, the
+** token "first" is substituted for "1st" by the tokenizer, then the query:
+**
+**
+** ... MATCH '1s*'
+**
+** will not match documents that contain the token "1st" (as the tokenizer
+** will probably not map "1s" to any prefix of "first").
+**
+** For full prefix support, method (3) may be preferred. In this case,
+** because the index contains entries for both "first" and "1st", prefix
+** queries such as 'fi*' or '1s*' will match correctly. However, because
+** extra entries are added to the FTS index, this method uses more space
+** within the database.
+**
+** Method (2) offers a midpoint between (1) and (3). Using this method,
+** a query such as '1s*' will match documents that contain the literal
+** token "1st", but not "first" (assuming the tokenizer is not able to
+** provide synonyms for prefixes). However, a non-prefix query like '1st'
+** will match against "1st" and "first". This method does not require
+** extra disk space, as no extra entries are added to the FTS index.
+** On the other hand, it may require more CPU cycles to run MATCH queries,
+** as separate queries of the FTS index are required for each synonym.
+**
+** When using methods (2) or (3), it is important that the tokenizer only
+** provide synonyms when tokenizing document text (method (2)) or query
+** text (method (3)), not both. Doing so will not cause any errors, but is
+** inefficient.
+*/
+typedef struct Fts5Tokenizer Fts5Tokenizer;
+typedef struct fts5_tokenizer fts5_tokenizer;
+struct fts5_tokenizer {
+ int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
+ void (*xDelete)(Fts5Tokenizer*);
+ int (*xTokenize)(Fts5Tokenizer*,
+ void *pCtx,
+ int flags, /* Mask of FTS5_TOKENIZE_* flags */
+ const char *pText, int nText,
+ int (*xToken)(
+ void *pCtx, /* Copy of 2nd argument to xTokenize() */
+ int tflags, /* Mask of FTS5_TOKEN_* flags */
+ const char *pToken, /* Pointer to buffer containing token */
+ int nToken, /* Size of token in bytes */
+ int iStart, /* Byte offset of token within input text */
+ int iEnd /* Byte offset of end of token within input text */
+ )
+ );
+};
+
+/* Flags that may be passed as the third argument to xTokenize() */
+#define FTS5_TOKENIZE_QUERY 0x0001
+#define FTS5_TOKENIZE_PREFIX 0x0002
+#define FTS5_TOKENIZE_DOCUMENT 0x0004
+#define FTS5_TOKENIZE_AUX 0x0008
+
+/* Flags that may be passed by the tokenizer implementation back to FTS5
+** as the third argument to the supplied xToken callback. */
+#define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */
+
+/*
+** END OF CUSTOM TOKENIZERS
+*************************************************************************/
+
+/*************************************************************************
+** FTS5 EXTENSION REGISTRATION API
+*/
+typedef struct fts5_api fts5_api;
+struct fts5_api {
+ int iVersion; /* Currently always set to 2 */
+
+ /* Create a new tokenizer */
+ int (*xCreateTokenizer)(
+ fts5_api *pApi,
+ const char *zName,
+ void *pContext,
+ fts5_tokenizer *pTokenizer,
+ void (*xDestroy)(void*)
+ );
+
+ /* Find an existing tokenizer */
+ int (*xFindTokenizer)(
+ fts5_api *pApi,
+ const char *zName,
+ void **ppContext,
+ fts5_tokenizer *pTokenizer
+ );
+
+ /* Create a new auxiliary function */
+ int (*xCreateFunction)(
+ fts5_api *pApi,
+ const char *zName,
+ void *pContext,
+ fts5_extension_function xFunction,
+ void (*xDestroy)(void*)
+ );
+};
+
+/*
+** END OF REGISTRATION API
+*************************************************************************/
+
+#if 0
+} /* end of the 'extern "C"' block */
+#endif
+
+#endif /* _FTS5_H */
+
+/******** End of fts5.h *********/
+
+/************** End of sqlite3.h *********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+
+/*
+** Include the configuration header output by 'configure' if we're using the
+** autoconf-based build
+*/
+#if defined(_HAVE_SQLITE_CONFIG_H) && !defined(SQLITECONFIG_H)
+/* #include "config.h" */
+#define SQLITECONFIG_H 1
+#endif
+
+/************** Include sqliteLimit.h in the middle of sqliteInt.h ***********/
+/************** Begin file sqliteLimit.h *************************************/
+/*
+** 2007 May 7
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file defines various limits of what SQLite can process.
+*/
+
+/*
+** The maximum length of a TEXT or BLOB in bytes. This also
+** limits the size of a row in a table or index.
+**
+** The hard limit is the ability of a 32-bit signed integer
+** to count the size: 2^31-1 or 2147483647.
+*/
+#ifndef SQLITE_MAX_LENGTH
+# define SQLITE_MAX_LENGTH 1000000000
+#endif
+
+/*
+** This is the maximum number of
+**
+** * Columns in a table
+** * Columns in an index
+** * Columns in a view
+** * Terms in the SET clause of an UPDATE statement
+** * Terms in the result set of a SELECT statement
+** * Terms in the GROUP BY or ORDER BY clauses of a SELECT statement.
+** * Terms in the VALUES clause of an INSERT statement
+**
+** The hard upper limit here is 32676. Most database people will
+** tell you that in a well-normalized database, you usually should
+** not have more than a dozen or so columns in any table. And if
+** that is the case, there is no point in having more than a few
+** dozen values in any of the other situations described above.
+*/
+#ifndef SQLITE_MAX_COLUMN
+# define SQLITE_MAX_COLUMN 2000
+#endif
+
+/*
+** The maximum length of a single SQL statement in bytes.
+**
+** It used to be the case that setting this value to zero would
+** turn the limit off. That is no longer true. It is not possible
+** to turn this limit off.
+*/
+#ifndef SQLITE_MAX_SQL_LENGTH
+# define SQLITE_MAX_SQL_LENGTH 1000000000
+#endif
+
+/*
+** The maximum depth of an expression tree. This is limited to
+** some extent by SQLITE_MAX_SQL_LENGTH. But sometime you might
+** want to place more severe limits on the complexity of an
+** expression.
+**
+** A value of 0 used to mean that the limit was not enforced.
+** But that is no longer true. The limit is now strictly enforced
+** at all times.
+*/
+#ifndef SQLITE_MAX_EXPR_DEPTH
+# define SQLITE_MAX_EXPR_DEPTH 1000
+#endif
+
+/*
+** The maximum number of terms in a compound SELECT statement.
+** The code generator for compound SELECT statements does one
+** level of recursion for each term. A stack overflow can result
+** if the number of terms is too large. In practice, most SQL
+** never has more than 3 or 4 terms. Use a value of 0 to disable
+** any limit on the number of terms in a compount SELECT.
+*/
+#ifndef SQLITE_MAX_COMPOUND_SELECT
+# define SQLITE_MAX_COMPOUND_SELECT 500
+#endif
+
+/*
+** The maximum number of opcodes in a VDBE program.
+** Not currently enforced.
+*/
+#ifndef SQLITE_MAX_VDBE_OP
+# define SQLITE_MAX_VDBE_OP 250000000
+#endif
+
+/*
+** The maximum number of arguments to an SQL function.
+*/
+#ifndef SQLITE_MAX_FUNCTION_ARG
+# define SQLITE_MAX_FUNCTION_ARG 127
+#endif
+
+/*
+** The suggested maximum number of in-memory pages to use for
+** the main database table and for temporary tables.
+**
+** IMPLEMENTATION-OF: R-30185-15359 The default suggested cache size is -2000,
+** which means the cache size is limited to 2048000 bytes of memory.
+** IMPLEMENTATION-OF: R-48205-43578 The default suggested cache size can be
+** altered using the SQLITE_DEFAULT_CACHE_SIZE compile-time options.
+*/
+#ifndef SQLITE_DEFAULT_CACHE_SIZE
+# define SQLITE_DEFAULT_CACHE_SIZE -2000
+#endif
+
+/*
+** The default number of frames to accumulate in the log file before
+** checkpointing the database in WAL mode.
+*/
+#ifndef SQLITE_DEFAULT_WAL_AUTOCHECKPOINT
+# define SQLITE_DEFAULT_WAL_AUTOCHECKPOINT 1000
+#endif
+
+/*
+** The maximum number of attached databases. This must be between 0
+** and 125. The upper bound of 125 is because the attached databases are
+** counted using a signed 8-bit integer which has a maximum value of 127
+** and we have to allow 2 extra counts for the "main" and "temp" databases.
+*/
+#ifndef SQLITE_MAX_ATTACHED
+# define SQLITE_MAX_ATTACHED 10
+#endif
+
+
+/*
+** The maximum value of a ?nnn wildcard that the parser will accept.
+*/
+#ifndef SQLITE_MAX_VARIABLE_NUMBER
+# define SQLITE_MAX_VARIABLE_NUMBER 999
+#endif
+
+/* Maximum page size. The upper bound on this value is 65536. This a limit
+** imposed by the use of 16-bit offsets within each page.
+**
+** Earlier versions of SQLite allowed the user to change this value at
+** compile time. This is no longer permitted, on the grounds that it creates
+** a library that is technically incompatible with an SQLite library
+** compiled with a different limit. If a process operating on a database
+** with a page-size of 65536 bytes crashes, then an instance of SQLite
+** compiled with the default page-size limit will not be able to rollback
+** the aborted transaction. This could lead to database corruption.
+*/
+#ifdef SQLITE_MAX_PAGE_SIZE
+# undef SQLITE_MAX_PAGE_SIZE
+#endif
+#define SQLITE_MAX_PAGE_SIZE 65536
+
+
+/*
+** The default size of a database page.
+*/
+#ifndef SQLITE_DEFAULT_PAGE_SIZE
+# define SQLITE_DEFAULT_PAGE_SIZE 4096
+#endif
+#if SQLITE_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
+# undef SQLITE_DEFAULT_PAGE_SIZE
+# define SQLITE_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
+#endif
+
+/*
+** Ordinarily, if no value is explicitly provided, SQLite creates databases
+** with page size SQLITE_DEFAULT_PAGE_SIZE. However, based on certain
+** device characteristics (sector-size and atomic write() support),
+** SQLite may choose a larger value. This constant is the maximum value
+** SQLite will choose on its own.
+*/
+#ifndef SQLITE_MAX_DEFAULT_PAGE_SIZE
+# define SQLITE_MAX_DEFAULT_PAGE_SIZE 8192
+#endif
+#if SQLITE_MAX_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
+# undef SQLITE_MAX_DEFAULT_PAGE_SIZE
+# define SQLITE_MAX_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
+#endif
+
+
+/*
+** Maximum number of pages in one database file.
+**
+** This is really just the default value for the max_page_count pragma.
+** This value can be lowered (or raised) at run-time using that the
+** max_page_count macro.
+*/
+#ifndef SQLITE_MAX_PAGE_COUNT
+# define SQLITE_MAX_PAGE_COUNT 1073741823
+#endif
+
+/*
+** Maximum length (in bytes) of the pattern in a LIKE or GLOB
+** operator.
+*/
+#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
+# define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
+#endif
+
+/*
+** Maximum depth of recursion for triggers.
+**
+** A value of 1 means that a trigger program will not be able to itself
+** fire any triggers. A value of 0 means that no trigger programs at all
+** may be executed.
+*/
+#ifndef SQLITE_MAX_TRIGGER_DEPTH
+# define SQLITE_MAX_TRIGGER_DEPTH 1000
+#endif
+
+/************** End of sqliteLimit.h *****************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+
+/* Disable nuisance warnings on Borland compilers */
+#if defined(__BORLANDC__)
+#pragma warn -rch /* unreachable code */
+#pragma warn -ccc /* Condition is always true or false */
+#pragma warn -aus /* Assigned value is never used */
+#pragma warn -csu /* Comparing signed and unsigned */
+#pragma warn -spa /* Suspicious pointer arithmetic */
+#endif
+
+/*
+** Include standard header files as necessary
+*/
+#ifdef HAVE_STDINT_H
+#include
+#endif
+#ifdef HAVE_INTTYPES_H
+#include
+#endif
+
+/*
+** The following macros are used to cast pointers to integers and
+** integers to pointers. The way you do this varies from one compiler
+** to the next, so we have developed the following set of #if statements
+** to generate appropriate macros for a wide range of compilers.
+**
+** The correct "ANSI" way to do this is to use the intptr_t type.
+** Unfortunately, that typedef is not available on all compilers, or
+** if it is available, it requires an #include of specific headers
+** that vary from one machine to the next.
+**
+** Ticket #3860: The llvm-gcc-4.2 compiler from Apple chokes on
+** the ((void*)&((char*)0)[X]) construct. But MSVC chokes on ((void*)(X)).
+** So we have to define the macros in different ways depending on the
+** compiler.
+*/
+#if defined(__PTRDIFF_TYPE__) /* This case should work for GCC */
+# define SQLITE_INT_TO_PTR(X) ((void*)(__PTRDIFF_TYPE__)(X))
+# define SQLITE_PTR_TO_INT(X) ((int)(__PTRDIFF_TYPE__)(X))
+#elif !defined(__GNUC__) /* Works for compilers other than LLVM */
+# define SQLITE_INT_TO_PTR(X) ((void*)&((char*)0)[X])
+# define SQLITE_PTR_TO_INT(X) ((int)(((char*)X)-(char*)0))
+#elif defined(HAVE_STDINT_H) /* Use this case if we have ANSI headers */
+# define SQLITE_INT_TO_PTR(X) ((void*)(intptr_t)(X))
+# define SQLITE_PTR_TO_INT(X) ((int)(intptr_t)(X))
+#else /* Generates a warning - but it always works */
+# define SQLITE_INT_TO_PTR(X) ((void*)(X))
+# define SQLITE_PTR_TO_INT(X) ((int)(X))
+#endif
+
+/*
+** A macro to hint to the compiler that a function should not be
+** inlined.
+*/
+#if defined(__GNUC__)
+# define SQLITE_NOINLINE __attribute__((noinline))
+#elif defined(_MSC_VER) && _MSC_VER>=1310
+# define SQLITE_NOINLINE __declspec(noinline)
+#else
+# define SQLITE_NOINLINE
+#endif
+
+/*
+** Make sure that the compiler intrinsics we desire are enabled when
+** compiling with an appropriate version of MSVC unless prevented by
+** the SQLITE_DISABLE_INTRINSIC define.
+*/
+#if !defined(SQLITE_DISABLE_INTRINSIC)
+# if defined(_MSC_VER) && _MSC_VER>=1400
+# if !defined(_WIN32_WCE)
+# include
+# pragma intrinsic(_byteswap_ushort)
+# pragma intrinsic(_byteswap_ulong)
+# pragma intrinsic(_byteswap_uint64)
+# pragma intrinsic(_ReadWriteBarrier)
+# else
+# include
+# endif
+# endif
+#endif
+
+/*
+** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
+** 0 means mutexes are permanently disable and the library is never
+** threadsafe. 1 means the library is serialized which is the highest
+** level of threadsafety. 2 means the library is multithreaded - multiple
+** threads can use SQLite as long as no two threads try to use the same
+** database connection at the same time.
+**
+** Older versions of SQLite used an optional THREADSAFE macro.
+** We support that for legacy.
+**
+** To ensure that the correct value of "THREADSAFE" is reported when querying
+** for compile-time options at runtime (e.g. "PRAGMA compile_options"), this
+** logic is partially replicated in ctime.c. If it is updated here, it should
+** also be updated there.
+*/
+#if !defined(SQLITE_THREADSAFE)
+# if defined(THREADSAFE)
+# define SQLITE_THREADSAFE THREADSAFE
+# else
+# define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
+# endif
+#endif
+
+/*
+** Powersafe overwrite is on by default. But can be turned off using
+** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
+*/
+#ifndef SQLITE_POWERSAFE_OVERWRITE
+# define SQLITE_POWERSAFE_OVERWRITE 1
+#endif
+
+/*
+** EVIDENCE-OF: R-25715-37072 Memory allocation statistics are enabled by
+** default unless SQLite is compiled with SQLITE_DEFAULT_MEMSTATUS=0 in
+** which case memory allocation statistics are disabled by default.
+*/
+#if !defined(SQLITE_DEFAULT_MEMSTATUS)
+# define SQLITE_DEFAULT_MEMSTATUS 1
+#endif
+
+/*
+** Exactly one of the following macros must be defined in order to
+** specify which memory allocation subsystem to use.
+**
+** SQLITE_SYSTEM_MALLOC // Use normal system malloc()
+** SQLITE_WIN32_MALLOC // Use Win32 native heap API
+** SQLITE_ZERO_MALLOC // Use a stub allocator that always fails
+** SQLITE_MEMDEBUG // Debugging version of system malloc()
+**
+** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
+** assert() macro is enabled, each call into the Win32 native heap subsystem
+** will cause HeapValidate to be called. If heap validation should fail, an
+** assertion will be triggered.
+**
+** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
+** the default.
+*/
+#if defined(SQLITE_SYSTEM_MALLOC) \
+ + defined(SQLITE_WIN32_MALLOC) \
+ + defined(SQLITE_ZERO_MALLOC) \
+ + defined(SQLITE_MEMDEBUG)>1
+# error "Two or more of the following compile-time configuration options\
+ are defined but at most one is allowed:\
+ SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
+ SQLITE_ZERO_MALLOC"
+#endif
+#if defined(SQLITE_SYSTEM_MALLOC) \
+ + defined(SQLITE_WIN32_MALLOC) \
+ + defined(SQLITE_ZERO_MALLOC) \
+ + defined(SQLITE_MEMDEBUG)==0
+# define SQLITE_SYSTEM_MALLOC 1
+#endif
+
+/*
+** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
+** sizes of memory allocations below this value where possible.
+*/
+#if !defined(SQLITE_MALLOC_SOFT_LIMIT)
+# define SQLITE_MALLOC_SOFT_LIMIT 1024
+#endif
+
+/*
+** We need to define _XOPEN_SOURCE as follows in order to enable
+** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
+** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
+** it.
+*/
+#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
+# define _XOPEN_SOURCE 600
+#endif
+
+/*
+** NDEBUG and SQLITE_DEBUG are opposites. It should always be true that
+** defined(NDEBUG)==!defined(SQLITE_DEBUG). If this is not currently true,
+** make it true by defining or undefining NDEBUG.
+**
+** Setting NDEBUG makes the code smaller and faster by disabling the
+** assert() statements in the code. So we want the default action
+** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
+** is set. Thus NDEBUG becomes an opt-in rather than an opt-out
+** feature.
+*/
+#if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
+# define NDEBUG 1
+#endif
+#if defined(NDEBUG) && defined(SQLITE_DEBUG)
+# undef NDEBUG
+#endif
+
+/*
+** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
+*/
+#if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
+# define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
+#endif
+
+/*
+** The testcase() macro is used to aid in coverage testing. When
+** doing coverage testing, the condition inside the argument to
+** testcase() must be evaluated both true and false in order to
+** get full branch coverage. The testcase() macro is inserted
+** to help ensure adequate test coverage in places where simple
+** condition/decision coverage is inadequate. For example, testcase()
+** can be used to make sure boundary values are tested. For
+** bitmask tests, testcase() can be used to make sure each bit
+** is significant and used at least once. On switch statements
+** where multiple cases go to the same block of code, testcase()
+** can insure that all cases are evaluated.
+**
+*/
+#ifdef SQLITE_COVERAGE_TEST
+SQLITE_PRIVATE void sqlite3Coverage(int);
+# define testcase(X) if( X ){ sqlite3Coverage(__LINE__); }
+#else
+# define testcase(X)
+#endif
+
+/*
+** The TESTONLY macro is used to enclose variable declarations or
+** other bits of code that are needed to support the arguments
+** within testcase() and assert() macros.
+*/
+#if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
+# define TESTONLY(X) X
+#else
+# define TESTONLY(X)
+#endif
+
+/*
+** Sometimes we need a small amount of code such as a variable initialization
+** to setup for a later assert() statement. We do not want this code to
+** appear when assert() is disabled. The following macro is therefore
+** used to contain that setup code. The "VVA" acronym stands for
+** "Verification, Validation, and Accreditation". In other words, the
+** code within VVA_ONLY() will only run during verification processes.
+*/
+#ifndef NDEBUG
+# define VVA_ONLY(X) X
+#else
+# define VVA_ONLY(X)
+#endif
+
+/*
+** The ALWAYS and NEVER macros surround boolean expressions which
+** are intended to always be true or false, respectively. Such
+** expressions could be omitted from the code completely. But they
+** are included in a few cases in order to enhance the resilience
+** of SQLite to unexpected behavior - to make the code "self-healing"
+** or "ductile" rather than being "brittle" and crashing at the first
+** hint of unplanned behavior.
+**
+** In other words, ALWAYS and NEVER are added for defensive code.
+**
+** When doing coverage testing ALWAYS and NEVER are hard-coded to
+** be true and false so that the unreachable code they specify will
+** not be counted as untested code.
+*/
+#if defined(SQLITE_COVERAGE_TEST) || defined(SQLITE_MUTATION_TEST)
+# define ALWAYS(X) (1)
+# define NEVER(X) (0)
+#elif !defined(NDEBUG)
+# define ALWAYS(X) ((X)?1:(assert(0),0))
+# define NEVER(X) ((X)?(assert(0),1):0)
+#else
+# define ALWAYS(X) (X)
+# define NEVER(X) (X)
+#endif
+
+/*
+** Some conditionals are optimizations only. In other words, if the
+** conditionals are replaced with a constant 1 (true) or 0 (false) then
+** the correct answer is still obtained, though perhaps not as quickly.
+**
+** The following macros mark these optimizations conditionals.
+*/
+#if defined(SQLITE_MUTATION_TEST)
+# define OK_IF_ALWAYS_TRUE(X) (1)
+# define OK_IF_ALWAYS_FALSE(X) (0)
+#else
+# define OK_IF_ALWAYS_TRUE(X) (X)
+# define OK_IF_ALWAYS_FALSE(X) (X)
+#endif
+
+/*
+** Some malloc failures are only possible if SQLITE_TEST_REALLOC_STRESS is
+** defined. We need to defend against those failures when testing with
+** SQLITE_TEST_REALLOC_STRESS, but we don't want the unreachable branches
+** during a normal build. The following macro can be used to disable tests
+** that are always false except when SQLITE_TEST_REALLOC_STRESS is set.
+*/
+#if defined(SQLITE_TEST_REALLOC_STRESS)
+# define ONLY_IF_REALLOC_STRESS(X) (X)
+#elif !defined(NDEBUG)
+# define ONLY_IF_REALLOC_STRESS(X) ((X)?(assert(0),1):0)
+#else
+# define ONLY_IF_REALLOC_STRESS(X) (0)
+#endif
+
+/*
+** Declarations used for tracing the operating system interfaces.
+*/
+#if defined(SQLITE_FORCE_OS_TRACE) || defined(SQLITE_TEST) || \
+ (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
+ extern int sqlite3OSTrace;
+# define OSTRACE(X) if( sqlite3OSTrace ) sqlite3DebugPrintf X
+# define SQLITE_HAVE_OS_TRACE
+#else
+# define OSTRACE(X)
+# undef SQLITE_HAVE_OS_TRACE
+#endif
+
+/*
+** Is the sqlite3ErrName() function needed in the build? Currently,
+** it is needed by "mutex_w32.c" (when debugging), "os_win.c" (when
+** OSTRACE is enabled), and by several "test*.c" files (which are
+** compiled using SQLITE_TEST).
+*/
+#if defined(SQLITE_HAVE_OS_TRACE) || defined(SQLITE_TEST) || \
+ (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
+# define SQLITE_NEED_ERR_NAME
+#else
+# undef SQLITE_NEED_ERR_NAME
+#endif
+
+/*
+** SQLITE_ENABLE_EXPLAIN_COMMENTS is incompatible with SQLITE_OMIT_EXPLAIN
+*/
+#ifdef SQLITE_OMIT_EXPLAIN
+# undef SQLITE_ENABLE_EXPLAIN_COMMENTS
+#endif
+
+/*
+** Return true (non-zero) if the input is an integer that is too large
+** to fit in 32-bits. This macro is used inside of various testcase()
+** macros to verify that we have tested SQLite for large-file support.
+*/
+#define IS_BIG_INT(X) (((X)&~(i64)0xffffffff)!=0)
+
+/*
+** The macro unlikely() is a hint that surrounds a boolean
+** expression that is usually false. Macro likely() surrounds
+** a boolean expression that is usually true. These hints could,
+** in theory, be used by the compiler to generate better code, but
+** currently they are just comments for human readers.
+*/
+#define likely(X) (X)
+#define unlikely(X) (X)
+
+/************** Include hash.h in the middle of sqliteInt.h ******************/
+/************** Begin file hash.h ********************************************/
+/*
+** 2001 September 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the header file for the generic hash-table implementation
+** used in SQLite.
+*/
+#ifndef SQLITE_HASH_H
+#define SQLITE_HASH_H
+
+/* Forward declarations of structures. */
+typedef struct Hash Hash;
+typedef struct HashElem HashElem;
+
+/* A complete hash table is an instance of the following structure.
+** The internals of this structure are intended to be opaque -- client
+** code should not attempt to access or modify the fields of this structure
+** directly. Change this structure only by using the routines below.
+** However, some of the "procedures" and "functions" for modifying and
+** accessing this structure are really macros, so we can't really make
+** this structure opaque.
+**
+** All elements of the hash table are on a single doubly-linked list.
+** Hash.first points to the head of this list.
+**
+** There are Hash.htsize buckets. Each bucket points to a spot in
+** the global doubly-linked list. The contents of the bucket are the
+** element pointed to plus the next _ht.count-1 elements in the list.
+**
+** Hash.htsize and Hash.ht may be zero. In that case lookup is done
+** by a linear search of the global list. For small tables, the
+** Hash.ht table is never allocated because if there are few elements
+** in the table, it is faster to do a linear search than to manage
+** the hash table.
+*/
+struct Hash {
+ unsigned int htsize; /* Number of buckets in the hash table */
+ unsigned int count; /* Number of entries in this table */
+ HashElem *first; /* The first element of the array */
+ struct _ht { /* the hash table */
+ int count; /* Number of entries with this hash */
+ HashElem *chain; /* Pointer to first entry with this hash */
+ } *ht;
+};
+
+/* Each element in the hash table is an instance of the following
+** structure. All elements are stored on a single doubly-linked list.
+**
+** Again, this structure is intended to be opaque, but it can't really
+** be opaque because it is used by macros.
+*/
+struct HashElem {
+ HashElem *next, *prev; /* Next and previous elements in the table */
+ void *data; /* Data associated with this element */
+ const char *pKey; /* Key associated with this element */
+};
+
+/*
+** Access routines. To delete, insert a NULL pointer.
+*/
+SQLITE_PRIVATE void sqlite3HashInit(Hash*);
+SQLITE_PRIVATE void *sqlite3HashInsert(Hash*, const char *pKey, void *pData);
+SQLITE_PRIVATE void *sqlite3HashFind(const Hash*, const char *pKey);
+SQLITE_PRIVATE void sqlite3HashClear(Hash*);
+
+/*
+** Macros for looping over all elements of a hash table. The idiom is
+** like this:
+**
+** Hash h;
+** HashElem *p;
+** ...
+** for(p=sqliteHashFirst(&h); p; p=sqliteHashNext(p)){
+** SomeStructure *pData = sqliteHashData(p);
+** // do something with pData
+** }
+*/
+#define sqliteHashFirst(H) ((H)->first)
+#define sqliteHashNext(E) ((E)->next)
+#define sqliteHashData(E) ((E)->data)
+/* #define sqliteHashKey(E) ((E)->pKey) // NOT USED */
+/* #define sqliteHashKeysize(E) ((E)->nKey) // NOT USED */
+
+/*
+** Number of entries in a hash table
+*/
+/* #define sqliteHashCount(H) ((H)->count) // NOT USED */
+
+#endif /* SQLITE_HASH_H */
+
+/************** End of hash.h ************************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include parse.h in the middle of sqliteInt.h *****************/
+/************** Begin file parse.h *******************************************/
+#define TK_SEMI 1
+#define TK_EXPLAIN 2
+#define TK_QUERY 3
+#define TK_PLAN 4
+#define TK_BEGIN 5
+#define TK_TRANSACTION 6
+#define TK_DEFERRED 7
+#define TK_IMMEDIATE 8
+#define TK_EXCLUSIVE 9
+#define TK_COMMIT 10
+#define TK_END 11
+#define TK_ROLLBACK 12
+#define TK_SAVEPOINT 13
+#define TK_RELEASE 14
+#define TK_TO 15
+#define TK_TABLE 16
+#define TK_CREATE 17
+#define TK_IF 18
+#define TK_NOT 19
+#define TK_EXISTS 20
+#define TK_TEMP 21
+#define TK_LP 22
+#define TK_RP 23
+#define TK_AS 24
+#define TK_WITHOUT 25
+#define TK_COMMA 26
+#define TK_ABORT 27
+#define TK_ACTION 28
+#define TK_AFTER 29
+#define TK_ANALYZE 30
+#define TK_ASC 31
+#define TK_ATTACH 32
+#define TK_BEFORE 33
+#define TK_BY 34
+#define TK_CASCADE 35
+#define TK_CAST 36
+#define TK_CONFLICT 37
+#define TK_DATABASE 38
+#define TK_DESC 39
+#define TK_DETACH 40
+#define TK_EACH 41
+#define TK_FAIL 42
+#define TK_OR 43
+#define TK_AND 44
+#define TK_IS 45
+#define TK_MATCH 46
+#define TK_LIKE_KW 47
+#define TK_BETWEEN 48
+#define TK_IN 49
+#define TK_ISNULL 50
+#define TK_NOTNULL 51
+#define TK_NE 52
+#define TK_EQ 53
+#define TK_GT 54
+#define TK_LE 55
+#define TK_LT 56
+#define TK_GE 57
+#define TK_ESCAPE 58
+#define TK_ID 59
+#define TK_COLUMNKW 60
+#define TK_DO 61
+#define TK_FOR 62
+#define TK_IGNORE 63
+#define TK_INITIALLY 64
+#define TK_INSTEAD 65
+#define TK_NO 66
+#define TK_KEY 67
+#define TK_OF 68
+#define TK_OFFSET 69
+#define TK_PRAGMA 70
+#define TK_RAISE 71
+#define TK_RECURSIVE 72
+#define TK_REPLACE 73
+#define TK_RESTRICT 74
+#define TK_ROW 75
+#define TK_ROWS 76
+#define TK_TRIGGER 77
+#define TK_VACUUM 78
+#define TK_VIEW 79
+#define TK_VIRTUAL 80
+#define TK_WITH 81
+#define TK_CURRENT 82
+#define TK_FOLLOWING 83
+#define TK_PARTITION 84
+#define TK_PRECEDING 85
+#define TK_RANGE 86
+#define TK_UNBOUNDED 87
+#define TK_REINDEX 88
+#define TK_RENAME 89
+#define TK_CTIME_KW 90
+#define TK_ANY 91
+#define TK_BITAND 92
+#define TK_BITOR 93
+#define TK_LSHIFT 94
+#define TK_RSHIFT 95
+#define TK_PLUS 96
+#define TK_MINUS 97
+#define TK_STAR 98
+#define TK_SLASH 99
+#define TK_REM 100
+#define TK_CONCAT 101
+#define TK_COLLATE 102
+#define TK_BITNOT 103
+#define TK_ON 104
+#define TK_INDEXED 105
+#define TK_STRING 106
+#define TK_JOIN_KW 107
+#define TK_CONSTRAINT 108
+#define TK_DEFAULT 109
+#define TK_NULL 110
+#define TK_PRIMARY 111
+#define TK_UNIQUE 112
+#define TK_CHECK 113
+#define TK_REFERENCES 114
+#define TK_AUTOINCR 115
+#define TK_INSERT 116
+#define TK_DELETE 117
+#define TK_UPDATE 118
+#define TK_SET 119
+#define TK_DEFERRABLE 120
+#define TK_FOREIGN 121
+#define TK_DROP 122
+#define TK_UNION 123
+#define TK_ALL 124
+#define TK_EXCEPT 125
+#define TK_INTERSECT 126
+#define TK_SELECT 127
+#define TK_VALUES 128
+#define TK_DISTINCT 129
+#define TK_DOT 130
+#define TK_FROM 131
+#define TK_JOIN 132
+#define TK_USING 133
+#define TK_ORDER 134
+#define TK_GROUP 135
+#define TK_HAVING 136
+#define TK_LIMIT 137
+#define TK_WHERE 138
+#define TK_INTO 139
+#define TK_NOTHING 140
+#define TK_FLOAT 141
+#define TK_BLOB 142
+#define TK_INTEGER 143
+#define TK_VARIABLE 144
+#define TK_CASE 145
+#define TK_WHEN 146
+#define TK_THEN 147
+#define TK_ELSE 148
+#define TK_INDEX 149
+#define TK_ALTER 150
+#define TK_ADD 151
+#define TK_WINDOW 152
+#define TK_OVER 153
+#define TK_FILTER 154
+#define TK_TRUEFALSE 155
+#define TK_ISNOT 156
+#define TK_FUNCTION 157
+#define TK_COLUMN 158
+#define TK_AGG_FUNCTION 159
+#define TK_AGG_COLUMN 160
+#define TK_UMINUS 161
+#define TK_UPLUS 162
+#define TK_TRUTH 163
+#define TK_REGISTER 164
+#define TK_VECTOR 165
+#define TK_SELECT_COLUMN 166
+#define TK_IF_NULL_ROW 167
+#define TK_ASTERISK 168
+#define TK_SPAN 169
+#define TK_END_OF_FILE 170
+#define TK_UNCLOSED_STRING 171
+#define TK_SPACE 172
+#define TK_ILLEGAL 173
+
+/* The token codes above must all fit in 8 bits */
+#define TKFLG_MASK 0xff
+
+/* Flags that can be added to a token code when it is not
+** being stored in a u8: */
+#define TKFLG_DONTFOLD 0x100 /* Omit constant folding optimizations */
+
+/************** End of parse.h ***********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+#include
+#include
+#include
+#include
+#include
+
+/*
+** Use a macro to replace memcpy() if compiled with SQLITE_INLINE_MEMCPY.
+** This allows better measurements of where memcpy() is used when running
+** cachegrind. But this macro version of memcpy() is very slow so it
+** should not be used in production. This is a performance measurement
+** hack only.
+*/
+#ifdef SQLITE_INLINE_MEMCPY
+# define memcpy(D,S,N) {char*xxd=(char*)(D);const char*xxs=(const char*)(S);\
+ int xxn=(N);while(xxn-->0)*(xxd++)=*(xxs++);}
+#endif
+
+/*
+** If compiling for a processor that lacks floating point support,
+** substitute integer for floating-point
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define double sqlite_int64
+# define float sqlite_int64
+# define LONGDOUBLE_TYPE sqlite_int64
+# ifndef SQLITE_BIG_DBL
+# define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
+# endif
+# define SQLITE_OMIT_DATETIME_FUNCS 1
+# define SQLITE_OMIT_TRACE 1
+# undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
+# undef SQLITE_HAVE_ISNAN
+#endif
+#ifndef SQLITE_BIG_DBL
+# define SQLITE_BIG_DBL (1e99)
+#endif
+
+/*
+** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
+** afterward. Having this macro allows us to cause the C compiler
+** to omit code used by TEMP tables without messy #ifndef statements.
+*/
+#ifdef SQLITE_OMIT_TEMPDB
+#define OMIT_TEMPDB 1
+#else
+#define OMIT_TEMPDB 0
+#endif
+
+/*
+** The "file format" number is an integer that is incremented whenever
+** the VDBE-level file format changes. The following macros define the
+** the default file format for new databases and the maximum file format
+** that the library can read.
+*/
+#define SQLITE_MAX_FILE_FORMAT 4
+#ifndef SQLITE_DEFAULT_FILE_FORMAT
+# define SQLITE_DEFAULT_FILE_FORMAT 4
+#endif
+
+/*
+** Determine whether triggers are recursive by default. This can be
+** changed at run-time using a pragma.
+*/
+#ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
+# define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
+#endif
+
+/*
+** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
+** on the command-line
+*/
+#ifndef SQLITE_TEMP_STORE
+# define SQLITE_TEMP_STORE 1
+#endif
+
+/*
+** If no value has been provided for SQLITE_MAX_WORKER_THREADS, or if
+** SQLITE_TEMP_STORE is set to 3 (never use temporary files), set it
+** to zero.
+*/
+#if SQLITE_TEMP_STORE==3 || SQLITE_THREADSAFE==0
+# undef SQLITE_MAX_WORKER_THREADS
+# define SQLITE_MAX_WORKER_THREADS 0
+#endif
+#ifndef SQLITE_MAX_WORKER_THREADS
+# define SQLITE_MAX_WORKER_THREADS 8
+#endif
+#ifndef SQLITE_DEFAULT_WORKER_THREADS
+# define SQLITE_DEFAULT_WORKER_THREADS 0
+#endif
+#if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
+# undef SQLITE_MAX_WORKER_THREADS
+# define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
+#endif
+
+/*
+** The default initial allocation for the pagecache when using separate
+** pagecaches for each database connection. A positive number is the
+** number of pages. A negative number N translations means that a buffer
+** of -1024*N bytes is allocated and used for as many pages as it will hold.
+**
+** The default value of "20" was choosen to minimize the run-time of the
+** speedtest1 test program with options: --shrink-memory --reprepare
+*/
+#ifndef SQLITE_DEFAULT_PCACHE_INITSZ
+# define SQLITE_DEFAULT_PCACHE_INITSZ 20
+#endif
+
+/*
+** Default value for the SQLITE_CONFIG_SORTERREF_SIZE option.
+*/
+#ifndef SQLITE_DEFAULT_SORTERREF_SIZE
+# define SQLITE_DEFAULT_SORTERREF_SIZE 0x7fffffff
+#endif
+
+/*
+** The compile-time options SQLITE_MMAP_READWRITE and
+** SQLITE_ENABLE_BATCH_ATOMIC_WRITE are not compatible with one another.
+** You must choose one or the other (or neither) but not both.
+*/
+#if defined(SQLITE_MMAP_READWRITE) && defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
+#error Cannot use both SQLITE_MMAP_READWRITE and SQLITE_ENABLE_BATCH_ATOMIC_WRITE
+#endif
+
+/*
+** GCC does not define the offsetof() macro so we'll have to do it
+** ourselves.
+*/
+#ifndef offsetof
+#define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
+#endif
+
+/*
+** Macros to compute minimum and maximum of two numbers.
+*/
+#ifndef MIN
+# define MIN(A,B) ((A)<(B)?(A):(B))
+#endif
+#ifndef MAX
+# define MAX(A,B) ((A)>(B)?(A):(B))
+#endif
+
+/*
+** Swap two objects of type TYPE.
+*/
+#define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
+
+/*
+** Check to see if this machine uses EBCDIC. (Yes, believe it or
+** not, there are still machines out there that use EBCDIC.)
+*/
+#if 'A' == '\301'
+# define SQLITE_EBCDIC 1
+#else
+# define SQLITE_ASCII 1
+#endif
+
+/*
+** Integers of known sizes. These typedefs might change for architectures
+** where the sizes very. Preprocessor macros are available so that the
+** types can be conveniently redefined at compile-type. Like this:
+**
+** cc '-DUINTPTR_TYPE=long long int' ...
+*/
+#ifndef UINT32_TYPE
+# ifdef HAVE_UINT32_T
+# define UINT32_TYPE uint32_t
+# else
+# define UINT32_TYPE unsigned int
+# endif
+#endif
+#ifndef UINT16_TYPE
+# ifdef HAVE_UINT16_T
+# define UINT16_TYPE uint16_t
+# else
+# define UINT16_TYPE unsigned short int
+# endif
+#endif
+#ifndef INT16_TYPE
+# ifdef HAVE_INT16_T
+# define INT16_TYPE int16_t
+# else
+# define INT16_TYPE short int
+# endif
+#endif
+#ifndef UINT8_TYPE
+# ifdef HAVE_UINT8_T
+# define UINT8_TYPE uint8_t
+# else
+# define UINT8_TYPE unsigned char
+# endif
+#endif
+#ifndef INT8_TYPE
+# ifdef HAVE_INT8_T
+# define INT8_TYPE int8_t
+# else
+# define INT8_TYPE signed char
+# endif
+#endif
+#ifndef LONGDOUBLE_TYPE
+# define LONGDOUBLE_TYPE long double
+#endif
+typedef sqlite_int64 i64; /* 8-byte signed integer */
+typedef sqlite_uint64 u64; /* 8-byte unsigned integer */
+typedef UINT32_TYPE u32; /* 4-byte unsigned integer */
+typedef UINT16_TYPE u16; /* 2-byte unsigned integer */
+typedef INT16_TYPE i16; /* 2-byte signed integer */
+typedef UINT8_TYPE u8; /* 1-byte unsigned integer */
+typedef INT8_TYPE i8; /* 1-byte signed integer */
+
+/*
+** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
+** that can be stored in a u32 without loss of data. The value
+** is 0x00000000ffffffff. But because of quirks of some compilers, we
+** have to specify the value in the less intuitive manner shown:
+*/
+#define SQLITE_MAX_U32 ((((u64)1)<<32)-1)
+
+/*
+** The datatype used to store estimates of the number of rows in a
+** table or index. This is an unsigned integer type. For 99.9% of
+** the world, a 32-bit integer is sufficient. But a 64-bit integer
+** can be used at compile-time if desired.
+*/
+#ifdef SQLITE_64BIT_STATS
+ typedef u64 tRowcnt; /* 64-bit only if requested at compile-time */
+#else
+ typedef u32 tRowcnt; /* 32-bit is the default */
+#endif
+
+/*
+** Estimated quantities used for query planning are stored as 16-bit
+** logarithms. For quantity X, the value stored is 10*log2(X). This
+** gives a possible range of values of approximately 1.0e986 to 1e-986.
+** But the allowed values are "grainy". Not every value is representable.
+** For example, quantities 16 and 17 are both represented by a LogEst
+** of 40. However, since LogEst quantities are suppose to be estimates,
+** not exact values, this imprecision is not a problem.
+**
+** "LogEst" is short for "Logarithmic Estimate".
+**
+** Examples:
+** 1 -> 0 20 -> 43 10000 -> 132
+** 2 -> 10 25 -> 46 25000 -> 146
+** 3 -> 16 100 -> 66 1000000 -> 199
+** 4 -> 20 1000 -> 99 1048576 -> 200
+** 10 -> 33 1024 -> 100 4294967296 -> 320
+**
+** The LogEst can be negative to indicate fractional values.
+** Examples:
+**
+** 0.5 -> -10 0.1 -> -33 0.0625 -> -40
+*/
+typedef INT16_TYPE LogEst;
+
+/*
+** Set the SQLITE_PTRSIZE macro to the number of bytes in a pointer
+*/
+#ifndef SQLITE_PTRSIZE
+# if defined(__SIZEOF_POINTER__)
+# define SQLITE_PTRSIZE __SIZEOF_POINTER__
+# elif defined(i386) || defined(__i386__) || defined(_M_IX86) || \
+ defined(_M_ARM) || defined(__arm__) || defined(__x86) || \
+ (defined(__TOS_AIX__) && !defined(__64BIT__))
+# define SQLITE_PTRSIZE 4
+# else
+# define SQLITE_PTRSIZE 8
+# endif
+#endif
+
+/* The uptr type is an unsigned integer large enough to hold a pointer
+*/
+#if defined(HAVE_STDINT_H)
+ typedef uintptr_t uptr;
+#elif SQLITE_PTRSIZE==4
+ typedef u32 uptr;
+#else
+ typedef u64 uptr;
+#endif
+
+/*
+** The SQLITE_WITHIN(P,S,E) macro checks to see if pointer P points to
+** something between S (inclusive) and E (exclusive).
+**
+** In other words, S is a buffer and E is a pointer to the first byte after
+** the end of buffer S. This macro returns true if P points to something
+** contained within the buffer S.
+*/
+#define SQLITE_WITHIN(P,S,E) (((uptr)(P)>=(uptr)(S))&&((uptr)(P)<(uptr)(E)))
+
+
+/*
+** Macros to determine whether the machine is big or little endian,
+** and whether or not that determination is run-time or compile-time.
+**
+** For best performance, an attempt is made to guess at the byte-order
+** using C-preprocessor macros. If that is unsuccessful, or if
+** -DSQLITE_BYTEORDER=0 is set, then byte-order is determined
+** at run-time.
+*/
+#ifndef SQLITE_BYTEORDER
+# if defined(i386) || defined(__i386__) || defined(_M_IX86) || \
+ defined(__x86_64) || defined(__x86_64__) || defined(_M_X64) || \
+ defined(_M_AMD64) || defined(_M_ARM) || defined(__x86) || \
+ defined(__arm__) || defined(_M_ARM64)
+# define SQLITE_BYTEORDER 1234
+# elif defined(sparc) || defined(__ppc__)
+# define SQLITE_BYTEORDER 4321
+# else
+# define SQLITE_BYTEORDER 0
+# endif
+#endif
+#if SQLITE_BYTEORDER==4321
+# define SQLITE_BIGENDIAN 1
+# define SQLITE_LITTLEENDIAN 0
+# define SQLITE_UTF16NATIVE SQLITE_UTF16BE
+#elif SQLITE_BYTEORDER==1234
+# define SQLITE_BIGENDIAN 0
+# define SQLITE_LITTLEENDIAN 1
+# define SQLITE_UTF16NATIVE SQLITE_UTF16LE
+#else
+# ifdef SQLITE_AMALGAMATION
+ const int sqlite3one = 1;
+# else
+ extern const int sqlite3one;
+# endif
+# define SQLITE_BIGENDIAN (*(char *)(&sqlite3one)==0)
+# define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
+# define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
+#endif
+
+/*
+** Constants for the largest and smallest possible 64-bit signed integers.
+** These macros are designed to work correctly on both 32-bit and 64-bit
+** compilers.
+*/
+#define LARGEST_INT64 (0xffffffff|(((i64)0x7fffffff)<<32))
+#define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
+
+/*
+** Round up a number to the next larger multiple of 8. This is used
+** to force 8-byte alignment on 64-bit architectures.
+*/
+#define ROUND8(x) (((x)+7)&~7)
+
+/*
+** Round down to the nearest multiple of 8
+*/
+#define ROUNDDOWN8(x) ((x)&~7)
+
+/*
+** Assert that the pointer X is aligned to an 8-byte boundary. This
+** macro is used only within assert() to verify that the code gets
+** all alignment restrictions correct.
+**
+** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
+** underlying malloc() implementation might return us 4-byte aligned
+** pointers. In that case, only verify 4-byte alignment.
+*/
+#ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
+# define EIGHT_BYTE_ALIGNMENT(X) ((((char*)(X) - (char*)0)&3)==0)
+#else
+# define EIGHT_BYTE_ALIGNMENT(X) ((((char*)(X) - (char*)0)&7)==0)
+#endif
+
+/*
+** Disable MMAP on platforms where it is known to not work
+*/
+#if defined(__OpenBSD__) || defined(__QNXNTO__)
+# undef SQLITE_MAX_MMAP_SIZE
+# define SQLITE_MAX_MMAP_SIZE 0
+#endif
+
+/*
+** Default maximum size of memory used by memory-mapped I/O in the VFS
+*/
+#ifdef __APPLE__
+# include
+#endif
+#ifndef SQLITE_MAX_MMAP_SIZE
+# if defined(__linux__) \
+ || defined(_WIN32) \
+ || (defined(__APPLE__) && defined(__MACH__)) \
+ || defined(__sun) \
+ || defined(__FreeBSD__) \
+ || defined(__DragonFly__)
+# define SQLITE_MAX_MMAP_SIZE 0x7fff0000 /* 2147418112 */
+# else
+# define SQLITE_MAX_MMAP_SIZE 0
+# endif
+#endif
+
+/*
+** The default MMAP_SIZE is zero on all platforms. Or, even if a larger
+** default MMAP_SIZE is specified at compile-time, make sure that it does
+** not exceed the maximum mmap size.
+*/
+#ifndef SQLITE_DEFAULT_MMAP_SIZE
+# define SQLITE_DEFAULT_MMAP_SIZE 0
+#endif
+#if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
+# undef SQLITE_DEFAULT_MMAP_SIZE
+# define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
+#endif
+
+/*
+** Only one of SQLITE_ENABLE_STAT3 or SQLITE_ENABLE_STAT4 can be defined.
+** Priority is given to SQLITE_ENABLE_STAT4. If either are defined, also
+** define SQLITE_ENABLE_STAT3_OR_STAT4
+*/
+#ifdef SQLITE_ENABLE_STAT4
+# undef SQLITE_ENABLE_STAT3
+# define SQLITE_ENABLE_STAT3_OR_STAT4 1
+#elif SQLITE_ENABLE_STAT3
+# define SQLITE_ENABLE_STAT3_OR_STAT4 1
+#elif SQLITE_ENABLE_STAT3_OR_STAT4
+# undef SQLITE_ENABLE_STAT3_OR_STAT4
+#endif
+
+/*
+** SELECTTRACE_ENABLED will be either 1 or 0 depending on whether or not
+** the Select query generator tracing logic is turned on.
+*/
+#if defined(SQLITE_ENABLE_SELECTTRACE)
+# define SELECTTRACE_ENABLED 1
+#else
+# define SELECTTRACE_ENABLED 0
+#endif
+
+/*
+** An instance of the following structure is used to store the busy-handler
+** callback for a given sqlite handle.
+**
+** The sqlite.busyHandler member of the sqlite struct contains the busy
+** callback for the database handle. Each pager opened via the sqlite
+** handle is passed a pointer to sqlite.busyHandler. The busy-handler
+** callback is currently invoked only from within pager.c.
+*/
+typedef struct BusyHandler BusyHandler;
+struct BusyHandler {
+ int (*xBusyHandler)(void *,int); /* The busy callback */
+ void *pBusyArg; /* First arg to busy callback */
+ int nBusy; /* Incremented with each busy call */
+ u8 bExtraFileArg; /* Include sqlite3_file as callback arg */
+};
+
+/*
+** Name of the master database table. The master database table
+** is a special table that holds the names and attributes of all
+** user tables and indices.
+*/
+#define MASTER_NAME "sqlite_master"
+#define TEMP_MASTER_NAME "sqlite_temp_master"
+
+/*
+** The root-page of the master database table.
+*/
+#define MASTER_ROOT 1
+
+/*
+** The name of the schema table.
+*/
+#define SCHEMA_TABLE(x) ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
+
+/*
+** A convenience macro that returns the number of elements in
+** an array.
+*/
+#define ArraySize(X) ((int)(sizeof(X)/sizeof(X[0])))
+
+/*
+** Determine if the argument is a power of two
+*/
+#define IsPowerOfTwo(X) (((X)&((X)-1))==0)
+
+/*
+** The following value as a destructor means to use sqlite3DbFree().
+** The sqlite3DbFree() routine requires two parameters instead of the
+** one parameter that destructors normally want. So we have to introduce
+** this magic value that the code knows to handle differently. Any
+** pointer will work here as long as it is distinct from SQLITE_STATIC
+** and SQLITE_TRANSIENT.
+*/
+#define SQLITE_DYNAMIC ((sqlite3_destructor_type)sqlite3MallocSize)
+
+/*
+** When SQLITE_OMIT_WSD is defined, it means that the target platform does
+** not support Writable Static Data (WSD) such as global and static variables.
+** All variables must either be on the stack or dynamically allocated from
+** the heap. When WSD is unsupported, the variable declarations scattered
+** throughout the SQLite code must become constants instead. The SQLITE_WSD
+** macro is used for this purpose. And instead of referencing the variable
+** directly, we use its constant as a key to lookup the run-time allocated
+** buffer that holds real variable. The constant is also the initializer
+** for the run-time allocated buffer.
+**
+** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
+** macros become no-ops and have zero performance impact.
+*/
+#ifdef SQLITE_OMIT_WSD
+ #define SQLITE_WSD const
+ #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
+ #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
+SQLITE_API int sqlite3_wsd_init(int N, int J);
+SQLITE_API void *sqlite3_wsd_find(void *K, int L);
+#else
+ #define SQLITE_WSD
+ #define GLOBAL(t,v) v
+ #define sqlite3GlobalConfig sqlite3Config
+#endif
+
+/*
+** The following macros are used to suppress compiler warnings and to
+** make it clear to human readers when a function parameter is deliberately
+** left unused within the body of a function. This usually happens when
+** a function is called via a function pointer. For example the
+** implementation of an SQL aggregate step callback may not use the
+** parameter indicating the number of arguments passed to the aggregate,
+** if it knows that this is enforced elsewhere.
+**
+** When a function parameter is not used at all within the body of a function,
+** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
+** However, these macros may also be used to suppress warnings related to
+** parameters that may or may not be used depending on compilation options.
+** For example those parameters only used in assert() statements. In these
+** cases the parameters are named as per the usual conventions.
+*/
+#define UNUSED_PARAMETER(x) (void)(x)
+#define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
+
+/*
+** Forward references to structures
+*/
+typedef struct AggInfo AggInfo;
+typedef struct AuthContext AuthContext;
+typedef struct AutoincInfo AutoincInfo;
+typedef struct Bitvec Bitvec;
+typedef struct CollSeq CollSeq;
+typedef struct Column Column;
+typedef struct Db Db;
+typedef struct Schema Schema;
+typedef struct Expr Expr;
+typedef struct ExprList ExprList;
+typedef struct FKey FKey;
+typedef struct FuncDestructor FuncDestructor;
+typedef struct FuncDef FuncDef;
+typedef struct FuncDefHash FuncDefHash;
+typedef struct IdList IdList;
+typedef struct Index Index;
+typedef struct IndexSample IndexSample;
+typedef struct KeyClass KeyClass;
+typedef struct KeyInfo KeyInfo;
+typedef struct Lookaside Lookaside;
+typedef struct LookasideSlot LookasideSlot;
+typedef struct Module Module;
+typedef struct NameContext NameContext;
+typedef struct Parse Parse;
+typedef struct PreUpdate PreUpdate;
+typedef struct PrintfArguments PrintfArguments;
+typedef struct RenameToken RenameToken;
+typedef struct RowSet RowSet;
+typedef struct Savepoint Savepoint;
+typedef struct Select Select;
+typedef struct SQLiteThread SQLiteThread;
+typedef struct SelectDest SelectDest;
+typedef struct SrcList SrcList;
+typedef struct sqlite3_str StrAccum; /* Internal alias for sqlite3_str */
+typedef struct Table Table;
+typedef struct TableLock TableLock;
+typedef struct Token Token;
+typedef struct TreeView TreeView;
+typedef struct Trigger Trigger;
+typedef struct TriggerPrg TriggerPrg;
+typedef struct TriggerStep TriggerStep;
+typedef struct UnpackedRecord UnpackedRecord;
+typedef struct Upsert Upsert;
+typedef struct VTable VTable;
+typedef struct VtabCtx VtabCtx;
+typedef struct Walker Walker;
+typedef struct WhereInfo WhereInfo;
+typedef struct Window Window;
+typedef struct With With;
+
+
+/*
+** The bitmask datatype defined below is used for various optimizations.
+**
+** Changing this from a 64-bit to a 32-bit type limits the number of
+** tables in a join to 32 instead of 64. But it also reduces the size
+** of the library by 738 bytes on ix86.
+*/
+#ifdef SQLITE_BITMASK_TYPE
+ typedef SQLITE_BITMASK_TYPE Bitmask;
+#else
+ typedef u64 Bitmask;
+#endif
+
+/*
+** The number of bits in a Bitmask. "BMS" means "BitMask Size".
+*/
+#define BMS ((int)(sizeof(Bitmask)*8))
+
+/*
+** A bit in a Bitmask
+*/
+#define MASKBIT(n) (((Bitmask)1)<<(n))
+#define MASKBIT32(n) (((unsigned int)1)<<(n))
+#define ALLBITS ((Bitmask)-1)
+
+/* A VList object records a mapping between parameters/variables/wildcards
+** in the SQL statement (such as $abc, @pqr, or :xyz) and the integer
+** variable number associated with that parameter. See the format description
+** on the sqlite3VListAdd() routine for more information. A VList is really
+** just an array of integers.
+*/
+typedef int VList;
+
+/*
+** Defer sourcing vdbe.h and btree.h until after the "u8" and
+** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
+** pointer types (i.e. FuncDef) defined above.
+*/
+/************** Include btree.h in the middle of sqliteInt.h *****************/
+/************** Begin file btree.h *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the sqlite B-Tree file
+** subsystem. See comments in the source code for a detailed description
+** of what each interface routine does.
+*/
+#ifndef SQLITE_BTREE_H
+#define SQLITE_BTREE_H
+
+/* TODO: This definition is just included so other modules compile. It
+** needs to be revisited.
+*/
+#define SQLITE_N_BTREE_META 16
+
+/*
+** If defined as non-zero, auto-vacuum is enabled by default. Otherwise
+** it must be turned on for each database using "PRAGMA auto_vacuum = 1".
+*/
+#ifndef SQLITE_DEFAULT_AUTOVACUUM
+ #define SQLITE_DEFAULT_AUTOVACUUM 0
+#endif
+
+#define BTREE_AUTOVACUUM_NONE 0 /* Do not do auto-vacuum */
+#define BTREE_AUTOVACUUM_FULL 1 /* Do full auto-vacuum */
+#define BTREE_AUTOVACUUM_INCR 2 /* Incremental vacuum */
+
+/*
+** Forward declarations of structure
+*/
+typedef struct Btree Btree;
+typedef struct BtCursor BtCursor;
+typedef struct BtShared BtShared;
+typedef struct BtreePayload BtreePayload;
+
+
+SQLITE_PRIVATE int sqlite3BtreeOpen(
+ sqlite3_vfs *pVfs, /* VFS to use with this b-tree */
+ const char *zFilename, /* Name of database file to open */
+ sqlite3 *db, /* Associated database connection */
+ Btree **ppBtree, /* Return open Btree* here */
+ int flags, /* Flags */
+ int vfsFlags /* Flags passed through to VFS open */
+);
+
+/* The flags parameter to sqlite3BtreeOpen can be the bitwise or of the
+** following values.
+**
+** NOTE: These values must match the corresponding PAGER_ values in
+** pager.h.
+*/
+#define BTREE_OMIT_JOURNAL 1 /* Do not create or use a rollback journal */
+#define BTREE_MEMORY 2 /* This is an in-memory DB */
+#define BTREE_SINGLE 4 /* The file contains at most 1 b-tree */
+#define BTREE_UNORDERED 8 /* Use of a hash implementation is OK */
+
+SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
+SQLITE_PRIVATE int sqlite3BtreeSetSpillSize(Btree*,int);
+#if SQLITE_MAX_MMAP_SIZE>0
+SQLITE_PRIVATE int sqlite3BtreeSetMmapLimit(Btree*,sqlite3_int64);
+#endif
+SQLITE_PRIVATE int sqlite3BtreeSetPagerFlags(Btree*,unsigned);
+SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int nPagesize, int nReserve, int eFix);
+SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeMaxPageCount(Btree*,int);
+SQLITE_PRIVATE u32 sqlite3BtreeLastPage(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeSecureDelete(Btree*,int);
+SQLITE_PRIVATE int sqlite3BtreeGetOptimalReserve(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeGetReserveNoMutex(Btree *p);
+SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *, int);
+SQLITE_PRIVATE int sqlite3BtreeGetAutoVacuum(Btree *);
+SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree*,int,int*);
+SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree*, const char *zMaster);
+SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree*, int);
+SQLITE_PRIVATE int sqlite3BtreeCommit(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeRollback(Btree*,int,int);
+SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree*,int);
+SQLITE_PRIVATE int sqlite3BtreeCreateTable(Btree*, int*, int flags);
+SQLITE_PRIVATE int sqlite3BtreeIsInTrans(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeIsInReadTrans(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeIsInBackup(Btree*);
+SQLITE_PRIVATE void *sqlite3BtreeSchema(Btree *, int, void(*)(void *));
+SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *pBtree);
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *pBtree, int iTab, u8 isWriteLock);
+#endif
+SQLITE_PRIVATE int sqlite3BtreeSavepoint(Btree *, int, int);
+
+SQLITE_PRIVATE const char *sqlite3BtreeGetFilename(Btree *);
+SQLITE_PRIVATE const char *sqlite3BtreeGetJournalname(Btree *);
+SQLITE_PRIVATE int sqlite3BtreeCopyFile(Btree *, Btree *);
+
+SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *);
+
+/* The flags parameter to sqlite3BtreeCreateTable can be the bitwise OR
+** of the flags shown below.
+**
+** Every SQLite table must have either BTREE_INTKEY or BTREE_BLOBKEY set.
+** With BTREE_INTKEY, the table key is a 64-bit integer and arbitrary data
+** is stored in the leaves. (BTREE_INTKEY is used for SQL tables.) With
+** BTREE_BLOBKEY, the key is an arbitrary BLOB and no content is stored
+** anywhere - the key is the content. (BTREE_BLOBKEY is used for SQL
+** indices.)
+*/
+#define BTREE_INTKEY 1 /* Table has only 64-bit signed integer keys */
+#define BTREE_BLOBKEY 2 /* Table has keys only - no data */
+
+SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree*, int, int*);
+SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree*, int, int*);
+SQLITE_PRIVATE int sqlite3BtreeClearTableOfCursor(BtCursor*);
+SQLITE_PRIVATE int sqlite3BtreeTripAllCursors(Btree*, int, int);
+
+SQLITE_PRIVATE void sqlite3BtreeGetMeta(Btree *pBtree, int idx, u32 *pValue);
+SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
+
+SQLITE_PRIVATE int sqlite3BtreeNewDb(Btree *p);
+
+/*
+** The second parameter to sqlite3BtreeGetMeta or sqlite3BtreeUpdateMeta
+** should be one of the following values. The integer values are assigned
+** to constants so that the offset of the corresponding field in an
+** SQLite database header may be found using the following formula:
+**
+** offset = 36 + (idx * 4)
+**
+** For example, the free-page-count field is located at byte offset 36 of
+** the database file header. The incr-vacuum-flag field is located at
+** byte offset 64 (== 36+4*7).
+**
+** The BTREE_DATA_VERSION value is not really a value stored in the header.
+** It is a read-only number computed by the pager. But we merge it with
+** the header value access routines since its access pattern is the same.
+** Call it a "virtual meta value".
+*/
+#define BTREE_FREE_PAGE_COUNT 0
+#define BTREE_SCHEMA_VERSION 1
+#define BTREE_FILE_FORMAT 2
+#define BTREE_DEFAULT_CACHE_SIZE 3
+#define BTREE_LARGEST_ROOT_PAGE 4
+#define BTREE_TEXT_ENCODING 5
+#define BTREE_USER_VERSION 6
+#define BTREE_INCR_VACUUM 7
+#define BTREE_APPLICATION_ID 8
+#define BTREE_DATA_VERSION 15 /* A virtual meta-value */
+
+/*
+** Kinds of hints that can be passed into the sqlite3BtreeCursorHint()
+** interface.
+**
+** BTREE_HINT_RANGE (arguments: Expr*, Mem*)
+**
+** The first argument is an Expr* (which is guaranteed to be constant for
+** the lifetime of the cursor) that defines constraints on which rows
+** might be fetched with this cursor. The Expr* tree may contain
+** TK_REGISTER nodes that refer to values stored in the array of registers
+** passed as the second parameter. In other words, if Expr.op==TK_REGISTER
+** then the value of the node is the value in Mem[pExpr.iTable]. Any
+** TK_COLUMN node in the expression tree refers to the Expr.iColumn-th
+** column of the b-tree of the cursor. The Expr tree will not contain
+** any function calls nor subqueries nor references to b-trees other than
+** the cursor being hinted.
+**
+** The design of the _RANGE hint is aid b-tree implementations that try
+** to prefetch content from remote machines - to provide those
+** implementations with limits on what needs to be prefetched and thereby
+** reduce network bandwidth.
+**
+** Note that BTREE_HINT_FLAGS with BTREE_BULKLOAD is the only hint used by
+** standard SQLite. The other hints are provided for extentions that use
+** the SQLite parser and code generator but substitute their own storage
+** engine.
+*/
+#define BTREE_HINT_RANGE 0 /* Range constraints on queries */
+
+/*
+** Values that may be OR'd together to form the argument to the
+** BTREE_HINT_FLAGS hint for sqlite3BtreeCursorHint():
+**
+** The BTREE_BULKLOAD flag is set on index cursors when the index is going
+** to be filled with content that is already in sorted order.
+**
+** The BTREE_SEEK_EQ flag is set on cursors that will get OP_SeekGE or
+** OP_SeekLE opcodes for a range search, but where the range of entries
+** selected will all have the same key. In other words, the cursor will
+** be used only for equality key searches.
+**
+*/
+#define BTREE_BULKLOAD 0x00000001 /* Used to full index in sorted order */
+#define BTREE_SEEK_EQ 0x00000002 /* EQ seeks only - no range seeks */
+
+/*
+** Flags passed as the third argument to sqlite3BtreeCursor().
+**
+** For read-only cursors the wrFlag argument is always zero. For read-write
+** cursors it may be set to either (BTREE_WRCSR|BTREE_FORDELETE) or just
+** (BTREE_WRCSR). If the BTREE_FORDELETE bit is set, then the cursor will
+** only be used by SQLite for the following:
+**
+** * to seek to and then delete specific entries, and/or
+**
+** * to read values that will be used to create keys that other
+** BTREE_FORDELETE cursors will seek to and delete.
+**
+** The BTREE_FORDELETE flag is an optimization hint. It is not used by
+** by this, the native b-tree engine of SQLite, but it is available to
+** alternative storage engines that might be substituted in place of this
+** b-tree system. For alternative storage engines in which a delete of
+** the main table row automatically deletes corresponding index rows,
+** the FORDELETE flag hint allows those alternative storage engines to
+** skip a lot of work. Namely: FORDELETE cursors may treat all SEEK
+** and DELETE operations as no-ops, and any READ operation against a
+** FORDELETE cursor may return a null row: 0x01 0x00.
+*/
+#define BTREE_WRCSR 0x00000004 /* read-write cursor */
+#define BTREE_FORDELETE 0x00000008 /* Cursor is for seek/delete only */
+
+SQLITE_PRIVATE int sqlite3BtreeCursor(
+ Btree*, /* BTree containing table to open */
+ int iTable, /* Index of root page */
+ int wrFlag, /* 1 for writing. 0 for read-only */
+ struct KeyInfo*, /* First argument to compare function */
+ BtCursor *pCursor /* Space to write cursor structure */
+);
+SQLITE_PRIVATE BtCursor *sqlite3BtreeFakeValidCursor(void);
+SQLITE_PRIVATE int sqlite3BtreeCursorSize(void);
+SQLITE_PRIVATE void sqlite3BtreeCursorZero(BtCursor*);
+SQLITE_PRIVATE void sqlite3BtreeCursorHintFlags(BtCursor*, unsigned);
+#ifdef SQLITE_ENABLE_CURSOR_HINTS
+SQLITE_PRIVATE void sqlite3BtreeCursorHint(BtCursor*, int, ...);
+#endif
+
+SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor*);
+SQLITE_PRIVATE int sqlite3BtreeMovetoUnpacked(
+ BtCursor*,
+ UnpackedRecord *pUnKey,
+ i64 intKey,
+ int bias,
+ int *pRes
+);
+SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor*);
+SQLITE_PRIVATE int sqlite3BtreeCursorRestore(BtCursor*, int*);
+SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor*, u8 flags);
+
+/* Allowed flags for sqlite3BtreeDelete() and sqlite3BtreeInsert() */
+#define BTREE_SAVEPOSITION 0x02 /* Leave cursor pointing at NEXT or PREV */
+#define BTREE_AUXDELETE 0x04 /* not the primary delete operation */
+#define BTREE_APPEND 0x08 /* Insert is likely an append */
+
+/* An instance of the BtreePayload object describes the content of a single
+** entry in either an index or table btree.
+**
+** Index btrees (used for indexes and also WITHOUT ROWID tables) contain
+** an arbitrary key and no data. These btrees have pKey,nKey set to the
+** key and the pData,nData,nZero fields are uninitialized. The aMem,nMem
+** fields give an array of Mem objects that are a decomposition of the key.
+** The nMem field might be zero, indicating that no decomposition is available.
+**
+** Table btrees (used for rowid tables) contain an integer rowid used as
+** the key and passed in the nKey field. The pKey field is zero.
+** pData,nData hold the content of the new entry. nZero extra zero bytes
+** are appended to the end of the content when constructing the entry.
+** The aMem,nMem fields are uninitialized for table btrees.
+**
+** Field usage summary:
+**
+** Table BTrees Index Btrees
+**
+** pKey always NULL encoded key
+** nKey the ROWID length of pKey
+** pData data not used
+** aMem not used decomposed key value
+** nMem not used entries in aMem
+** nData length of pData not used
+** nZero extra zeros after pData not used
+**
+** This object is used to pass information into sqlite3BtreeInsert(). The
+** same information used to be passed as five separate parameters. But placing
+** the information into this object helps to keep the interface more
+** organized and understandable, and it also helps the resulting code to
+** run a little faster by using fewer registers for parameter passing.
+*/
+struct BtreePayload {
+ const void *pKey; /* Key content for indexes. NULL for tables */
+ sqlite3_int64 nKey; /* Size of pKey for indexes. PRIMARY KEY for tabs */
+ const void *pData; /* Data for tables. */
+ sqlite3_value *aMem; /* First of nMem value in the unpacked pKey */
+ u16 nMem; /* Number of aMem[] value. Might be zero */
+ int nData; /* Size of pData. 0 if none. */
+ int nZero; /* Extra zero data appended after pData,nData */
+};
+
+SQLITE_PRIVATE int sqlite3BtreeInsert(BtCursor*, const BtreePayload *pPayload,
+ int flags, int seekResult);
+SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor*, int *pRes);
+#ifndef SQLITE_OMIT_WINDOWFUNC
+SQLITE_PRIVATE void sqlite3BtreeSkipNext(BtCursor*);
+#endif
+SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor*, int *pRes);
+SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor*, int flags);
+SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor*);
+SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor*, int flags);
+SQLITE_PRIVATE i64 sqlite3BtreeIntegerKey(BtCursor*);
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+SQLITE_PRIVATE i64 sqlite3BtreeOffset(BtCursor*);
+#endif
+SQLITE_PRIVATE int sqlite3BtreePayload(BtCursor*, u32 offset, u32 amt, void*);
+SQLITE_PRIVATE const void *sqlite3BtreePayloadFetch(BtCursor*, u32 *pAmt);
+SQLITE_PRIVATE u32 sqlite3BtreePayloadSize(BtCursor*);
+
+SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
+SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);
+SQLITE_PRIVATE i64 sqlite3BtreeRowCountEst(BtCursor*);
+
+#ifndef SQLITE_OMIT_INCRBLOB
+SQLITE_PRIVATE int sqlite3BtreePayloadChecked(BtCursor*, u32 offset, u32 amt, void*);
+SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
+SQLITE_PRIVATE void sqlite3BtreeIncrblobCursor(BtCursor *);
+#endif
+SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *);
+SQLITE_PRIVATE int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
+SQLITE_PRIVATE int sqlite3BtreeCursorHasHint(BtCursor*, unsigned int mask);
+SQLITE_PRIVATE int sqlite3BtreeIsReadonly(Btree *pBt);
+SQLITE_PRIVATE int sqlite3HeaderSizeBtree(void);
+
+#ifndef NDEBUG
+SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor*);
+#endif
+SQLITE_PRIVATE int sqlite3BtreeCursorIsValidNN(BtCursor*);
+
+#ifndef SQLITE_OMIT_BTREECOUNT
+SQLITE_PRIVATE int sqlite3BtreeCount(BtCursor *, i64 *);
+#endif
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
+SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
+#endif
+
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE int sqlite3BtreeCheckpoint(Btree*, int, int *, int *);
+#endif
+
+/*
+** If we are not using shared cache, then there is no need to
+** use mutexes to access the BtShared structures. So make the
+** Enter and Leave procedures no-ops.
+*/
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE void sqlite3BtreeEnter(Btree*);
+SQLITE_PRIVATE void sqlite3BtreeEnterAll(sqlite3*);
+SQLITE_PRIVATE int sqlite3BtreeSharable(Btree*);
+SQLITE_PRIVATE void sqlite3BtreeEnterCursor(BtCursor*);
+SQLITE_PRIVATE int sqlite3BtreeConnectionCount(Btree*);
+#else
+# define sqlite3BtreeEnter(X)
+# define sqlite3BtreeEnterAll(X)
+# define sqlite3BtreeSharable(X) 0
+# define sqlite3BtreeEnterCursor(X)
+# define sqlite3BtreeConnectionCount(X) 1
+#endif
+
+#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE
+SQLITE_PRIVATE void sqlite3BtreeLeave(Btree*);
+SQLITE_PRIVATE void sqlite3BtreeLeaveCursor(BtCursor*);
+SQLITE_PRIVATE void sqlite3BtreeLeaveAll(sqlite3*);
+#ifndef NDEBUG
+ /* These routines are used inside assert() statements only. */
+SQLITE_PRIVATE int sqlite3BtreeHoldsMutex(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeHoldsAllMutexes(sqlite3*);
+SQLITE_PRIVATE int sqlite3SchemaMutexHeld(sqlite3*,int,Schema*);
+#endif
+#else
+
+# define sqlite3BtreeLeave(X)
+# define sqlite3BtreeLeaveCursor(X)
+# define sqlite3BtreeLeaveAll(X)
+
+# define sqlite3BtreeHoldsMutex(X) 1
+# define sqlite3BtreeHoldsAllMutexes(X) 1
+# define sqlite3SchemaMutexHeld(X,Y,Z) 1
+#endif
+
+
+#endif /* SQLITE_BTREE_H */
+
+/************** End of btree.h ***********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include vdbe.h in the middle of sqliteInt.h ******************/
+/************** Begin file vdbe.h ********************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Header file for the Virtual DataBase Engine (VDBE)
+**
+** This header defines the interface to the virtual database engine
+** or VDBE. The VDBE implements an abstract machine that runs a
+** simple program to access and modify the underlying database.
+*/
+#ifndef SQLITE_VDBE_H
+#define SQLITE_VDBE_H
+/* #include */
+
+/*
+** A single VDBE is an opaque structure named "Vdbe". Only routines
+** in the source file sqliteVdbe.c are allowed to see the insides
+** of this structure.
+*/
+typedef struct Vdbe Vdbe;
+
+/*
+** The names of the following types declared in vdbeInt.h are required
+** for the VdbeOp definition.
+*/
+typedef struct sqlite3_value Mem;
+typedef struct SubProgram SubProgram;
+
+/*
+** A single instruction of the virtual machine has an opcode
+** and as many as three operands. The instruction is recorded
+** as an instance of the following structure:
+*/
+struct VdbeOp {
+ u8 opcode; /* What operation to perform */
+ signed char p4type; /* One of the P4_xxx constants for p4 */
+ u16 p5; /* Fifth parameter is an unsigned 16-bit integer */
+ int p1; /* First operand */
+ int p2; /* Second parameter (often the jump destination) */
+ int p3; /* The third parameter */
+ union p4union { /* fourth parameter */
+ int i; /* Integer value if p4type==P4_INT32 */
+ void *p; /* Generic pointer */
+ char *z; /* Pointer to data for string (char array) types */
+ i64 *pI64; /* Used when p4type is P4_INT64 */
+ double *pReal; /* Used when p4type is P4_REAL */
+ FuncDef *pFunc; /* Used when p4type is P4_FUNCDEF */
+ sqlite3_context *pCtx; /* Used when p4type is P4_FUNCCTX */
+ CollSeq *pColl; /* Used when p4type is P4_COLLSEQ */
+ Mem *pMem; /* Used when p4type is P4_MEM */
+ VTable *pVtab; /* Used when p4type is P4_VTAB */
+ KeyInfo *pKeyInfo; /* Used when p4type is P4_KEYINFO */
+ int *ai; /* Used when p4type is P4_INTARRAY */
+ SubProgram *pProgram; /* Used when p4type is P4_SUBPROGRAM */
+ Table *pTab; /* Used when p4type is P4_TABLE */
+#ifdef SQLITE_ENABLE_CURSOR_HINTS
+ Expr *pExpr; /* Used when p4type is P4_EXPR */
+#endif
+ int (*xAdvance)(BtCursor *, int);
+ } p4;
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
+ char *zComment; /* Comment to improve readability */
+#endif
+#ifdef VDBE_PROFILE
+ u32 cnt; /* Number of times this instruction was executed */
+ u64 cycles; /* Total time spent executing this instruction */
+#endif
+#ifdef SQLITE_VDBE_COVERAGE
+ u32 iSrcLine; /* Source-code line that generated this opcode
+ ** with flags in the upper 8 bits */
+#endif
+};
+typedef struct VdbeOp VdbeOp;
+
+
+/*
+** A sub-routine used to implement a trigger program.
+*/
+struct SubProgram {
+ VdbeOp *aOp; /* Array of opcodes for sub-program */
+ int nOp; /* Elements in aOp[] */
+ int nMem; /* Number of memory cells required */
+ int nCsr; /* Number of cursors required */
+ u8 *aOnce; /* Array of OP_Once flags */
+ void *token; /* id that may be used to recursive triggers */
+ SubProgram *pNext; /* Next sub-program already visited */
+};
+
+/*
+** A smaller version of VdbeOp used for the VdbeAddOpList() function because
+** it takes up less space.
+*/
+struct VdbeOpList {
+ u8 opcode; /* What operation to perform */
+ signed char p1; /* First operand */
+ signed char p2; /* Second parameter (often the jump destination) */
+ signed char p3; /* Third parameter */
+};
+typedef struct VdbeOpList VdbeOpList;
+
+/*
+** Allowed values of VdbeOp.p4type
+*/
+#define P4_NOTUSED 0 /* The P4 parameter is not used */
+#define P4_TRANSIENT 0 /* P4 is a pointer to a transient string */
+#define P4_STATIC (-1) /* Pointer to a static string */
+#define P4_COLLSEQ (-2) /* P4 is a pointer to a CollSeq structure */
+#define P4_INT32 (-3) /* P4 is a 32-bit signed integer */
+#define P4_SUBPROGRAM (-4) /* P4 is a pointer to a SubProgram structure */
+#define P4_ADVANCE (-5) /* P4 is a pointer to BtreeNext() or BtreePrev() */
+#define P4_TABLE (-6) /* P4 is a pointer to a Table structure */
+/* Above do not own any resources. Must free those below */
+#define P4_FREE_IF_LE (-7)
+#define P4_DYNAMIC (-7) /* Pointer to memory from sqliteMalloc() */
+#define P4_FUNCDEF (-8) /* P4 is a pointer to a FuncDef structure */
+#define P4_KEYINFO (-9) /* P4 is a pointer to a KeyInfo structure */
+#define P4_EXPR (-10) /* P4 is a pointer to an Expr tree */
+#define P4_MEM (-11) /* P4 is a pointer to a Mem* structure */
+#define P4_VTAB (-12) /* P4 is a pointer to an sqlite3_vtab structure */
+#define P4_REAL (-13) /* P4 is a 64-bit floating point value */
+#define P4_INT64 (-14) /* P4 is a 64-bit signed integer */
+#define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
+#define P4_FUNCCTX (-16) /* P4 is a pointer to an sqlite3_context object */
+#define P4_DYNBLOB (-17) /* Pointer to memory from sqliteMalloc() */
+
+/* Error message codes for OP_Halt */
+#define P5_ConstraintNotNull 1
+#define P5_ConstraintUnique 2
+#define P5_ConstraintCheck 3
+#define P5_ConstraintFK 4
+
+/*
+** The Vdbe.aColName array contains 5n Mem structures, where n is the
+** number of columns of data returned by the statement.
+*/
+#define COLNAME_NAME 0
+#define COLNAME_DECLTYPE 1
+#define COLNAME_DATABASE 2
+#define COLNAME_TABLE 3
+#define COLNAME_COLUMN 4
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
+# define COLNAME_N 5 /* Number of COLNAME_xxx symbols */
+#else
+# ifdef SQLITE_OMIT_DECLTYPE
+# define COLNAME_N 1 /* Store only the name */
+# else
+# define COLNAME_N 2 /* Store the name and decltype */
+# endif
+#endif
+
+/*
+** The following macro converts a relative address in the p2 field
+** of a VdbeOp structure into a negative number so that
+** sqlite3VdbeAddOpList() knows that the address is relative. Calling
+** the macro again restores the address.
+*/
+#define ADDR(X) (-1-(X))
+
+/*
+** The makefile scans the vdbe.c source file and creates the "opcodes.h"
+** header file that defines a number for each opcode used by the VDBE.
+*/
+/************** Include opcodes.h in the middle of vdbe.h ********************/
+/************** Begin file opcodes.h *****************************************/
+/* Automatically generated. Do not edit */
+/* See the tool/mkopcodeh.tcl script for details */
+#define OP_Savepoint 0
+#define OP_AutoCommit 1
+#define OP_Transaction 2
+#define OP_SorterNext 3 /* jump */
+#define OP_Prev 4 /* jump */
+#define OP_Next 5 /* jump */
+#define OP_Checkpoint 6
+#define OP_JournalMode 7
+#define OP_Vacuum 8
+#define OP_VFilter 9 /* jump, synopsis: iplan=r[P3] zplan='P4' */
+#define OP_VUpdate 10 /* synopsis: data=r[P3@P2] */
+#define OP_Goto 11 /* jump */
+#define OP_Gosub 12 /* jump */
+#define OP_InitCoroutine 13 /* jump */
+#define OP_Yield 14 /* jump */
+#define OP_MustBeInt 15 /* jump */
+#define OP_Jump 16 /* jump */
+#define OP_Once 17 /* jump */
+#define OP_If 18 /* jump */
+#define OP_Not 19 /* same as TK_NOT, synopsis: r[P2]= !r[P1] */
+#define OP_IfNot 20 /* jump */
+#define OP_IfNullRow 21 /* jump, synopsis: if P1.nullRow then r[P3]=NULL, goto P2 */
+#define OP_SeekLT 22 /* jump, synopsis: key=r[P3@P4] */
+#define OP_SeekLE 23 /* jump, synopsis: key=r[P3@P4] */
+#define OP_SeekGE 24 /* jump, synopsis: key=r[P3@P4] */
+#define OP_SeekGT 25 /* jump, synopsis: key=r[P3@P4] */
+#define OP_IfNoHope 26 /* jump, synopsis: key=r[P3@P4] */
+#define OP_NoConflict 27 /* jump, synopsis: key=r[P3@P4] */
+#define OP_NotFound 28 /* jump, synopsis: key=r[P3@P4] */
+#define OP_Found 29 /* jump, synopsis: key=r[P3@P4] */
+#define OP_SeekRowid 30 /* jump, synopsis: intkey=r[P3] */
+#define OP_NotExists 31 /* jump, synopsis: intkey=r[P3] */
+#define OP_Last 32 /* jump */
+#define OP_IfSmaller 33 /* jump */
+#define OP_SorterSort 34 /* jump */
+#define OP_Sort 35 /* jump */
+#define OP_Rewind 36 /* jump */
+#define OP_IdxLE 37 /* jump, synopsis: key=r[P3@P4] */
+#define OP_IdxGT 38 /* jump, synopsis: key=r[P3@P4] */
+#define OP_IdxLT 39 /* jump, synopsis: key=r[P3@P4] */
+#define OP_IdxGE 40 /* jump, synopsis: key=r[P3@P4] */
+#define OP_RowSetRead 41 /* jump, synopsis: r[P3]=rowset(P1) */
+#define OP_RowSetTest 42 /* jump, synopsis: if r[P3] in rowset(P1) goto P2 */
+#define OP_Or 43 /* same as TK_OR, synopsis: r[P3]=(r[P1] || r[P2]) */
+#define OP_And 44 /* same as TK_AND, synopsis: r[P3]=(r[P1] && r[P2]) */
+#define OP_Program 45 /* jump */
+#define OP_FkIfZero 46 /* jump, synopsis: if fkctr[P1]==0 goto P2 */
+#define OP_IfPos 47 /* jump, synopsis: if r[P1]>0 then r[P1]-=P3, goto P2 */
+#define OP_IfNotZero 48 /* jump, synopsis: if r[P1]!=0 then r[P1]--, goto P2 */
+#define OP_DecrJumpZero 49 /* jump, synopsis: if (--r[P1])==0 goto P2 */
+#define OP_IsNull 50 /* jump, same as TK_ISNULL, synopsis: if r[P1]==NULL goto P2 */
+#define OP_NotNull 51 /* jump, same as TK_NOTNULL, synopsis: if r[P1]!=NULL goto P2 */
+#define OP_Ne 52 /* jump, same as TK_NE, synopsis: IF r[P3]!=r[P1] */
+#define OP_Eq 53 /* jump, same as TK_EQ, synopsis: IF r[P3]==r[P1] */
+#define OP_Gt 54 /* jump, same as TK_GT, synopsis: IF r[P3]>r[P1] */
+#define OP_Le 55 /* jump, same as TK_LE, synopsis: IF r[P3]<=r[P1] */
+#define OP_Lt 56 /* jump, same as TK_LT, synopsis: IF r[P3]=r[P1] */
+#define OP_ElseNotEq 58 /* jump, same as TK_ESCAPE */
+#define OP_IncrVacuum 59 /* jump */
+#define OP_VNext 60 /* jump */
+#define OP_Init 61 /* jump, synopsis: Start at P2 */
+#define OP_PureFunc0 62
+#define OP_Function0 63 /* synopsis: r[P3]=func(r[P2@P5]) */
+#define OP_PureFunc 64
+#define OP_Function 65 /* synopsis: r[P3]=func(r[P2@P5]) */
+#define OP_Return 66
+#define OP_EndCoroutine 67
+#define OP_HaltIfNull 68 /* synopsis: if r[P3]=null halt */
+#define OP_Halt 69
+#define OP_Integer 70 /* synopsis: r[P2]=P1 */
+#define OP_Int64 71 /* synopsis: r[P2]=P4 */
+#define OP_String 72 /* synopsis: r[P2]='P4' (len=P1) */
+#define OP_Null 73 /* synopsis: r[P2..P3]=NULL */
+#define OP_SoftNull 74 /* synopsis: r[P1]=NULL */
+#define OP_Blob 75 /* synopsis: r[P2]=P4 (len=P1) */
+#define OP_Variable 76 /* synopsis: r[P2]=parameter(P1,P4) */
+#define OP_Move 77 /* synopsis: r[P2@P3]=r[P1@P3] */
+#define OP_Copy 78 /* synopsis: r[P2@P3+1]=r[P1@P3+1] */
+#define OP_SCopy 79 /* synopsis: r[P2]=r[P1] */
+#define OP_IntCopy 80 /* synopsis: r[P2]=r[P1] */
+#define OP_ResultRow 81 /* synopsis: output=r[P1@P2] */
+#define OP_CollSeq 82
+#define OP_AddImm 83 /* synopsis: r[P1]=r[P1]+P2 */
+#define OP_RealAffinity 84
+#define OP_Cast 85 /* synopsis: affinity(r[P1]) */
+#define OP_Permutation 86
+#define OP_Compare 87 /* synopsis: r[P1@P3] <-> r[P2@P3] */
+#define OP_IsTrue 88 /* synopsis: r[P2] = coalesce(r[P1]==TRUE,P3) ^ P4 */
+#define OP_Offset 89 /* synopsis: r[P3] = sqlite_offset(P1) */
+#define OP_Column 90 /* synopsis: r[P3]=PX */
+#define OP_Affinity 91 /* synopsis: affinity(r[P1@P2]) */
+#define OP_BitAnd 92 /* same as TK_BITAND, synopsis: r[P3]=r[P1]&r[P2] */
+#define OP_BitOr 93 /* same as TK_BITOR, synopsis: r[P3]=r[P1]|r[P2] */
+#define OP_ShiftLeft 94 /* same as TK_LSHIFT, synopsis: r[P3]=r[P2]<>r[P1] */
+#define OP_Add 96 /* same as TK_PLUS, synopsis: r[P3]=r[P1]+r[P2] */
+#define OP_Subtract 97 /* same as TK_MINUS, synopsis: r[P3]=r[P2]-r[P1] */
+#define OP_Multiply 98 /* same as TK_STAR, synopsis: r[P3]=r[P1]*r[P2] */
+#define OP_Divide 99 /* same as TK_SLASH, synopsis: r[P3]=r[P2]/r[P1] */
+#define OP_Remainder 100 /* same as TK_REM, synopsis: r[P3]=r[P2]%r[P1] */
+#define OP_Concat 101 /* same as TK_CONCAT, synopsis: r[P3]=r[P2]+r[P1] */
+#define OP_MakeRecord 102 /* synopsis: r[P3]=mkrec(r[P1@P2]) */
+#define OP_BitNot 103 /* same as TK_BITNOT, synopsis: r[P2]= ~r[P1] */
+#define OP_Count 104 /* synopsis: r[P2]=count() */
+#define OP_ReadCookie 105
+#define OP_String8 106 /* same as TK_STRING, synopsis: r[P2]='P4' */
+#define OP_SetCookie 107
+#define OP_ReopenIdx 108 /* synopsis: root=P2 iDb=P3 */
+#define OP_OpenRead 109 /* synopsis: root=P2 iDb=P3 */
+#define OP_OpenWrite 110 /* synopsis: root=P2 iDb=P3 */
+#define OP_OpenDup 111
+#define OP_OpenAutoindex 112 /* synopsis: nColumn=P2 */
+#define OP_OpenEphemeral 113 /* synopsis: nColumn=P2 */
+#define OP_SorterOpen 114
+#define OP_SequenceTest 115 /* synopsis: if( cursor[P1].ctr++ ) pc = P2 */
+#define OP_OpenPseudo 116 /* synopsis: P3 columns in r[P2] */
+#define OP_Close 117
+#define OP_ColumnsUsed 118
+#define OP_SeekHit 119 /* synopsis: seekHit=P2 */
+#define OP_Sequence 120 /* synopsis: r[P2]=cursor[P1].ctr++ */
+#define OP_NewRowid 121 /* synopsis: r[P2]=rowid */
+#define OP_Insert 122 /* synopsis: intkey=r[P3] data=r[P2] */
+#define OP_InsertInt 123 /* synopsis: intkey=P3 data=r[P2] */
+#define OP_Delete 124
+#define OP_ResetCount 125
+#define OP_SorterCompare 126 /* synopsis: if key(P1)!=trim(r[P3],P4) goto P2 */
+#define OP_SorterData 127 /* synopsis: r[P2]=data */
+#define OP_RowData 128 /* synopsis: r[P2]=data */
+#define OP_Rowid 129 /* synopsis: r[P2]=rowid */
+#define OP_NullRow 130
+#define OP_SeekEnd 131
+#define OP_SorterInsert 132 /* synopsis: key=r[P2] */
+#define OP_IdxInsert 133 /* synopsis: key=r[P2] */
+#define OP_IdxDelete 134 /* synopsis: key=r[P2@P3] */
+#define OP_DeferredSeek 135 /* synopsis: Move P3 to P1.rowid if needed */
+#define OP_IdxRowid 136 /* synopsis: r[P2]=rowid */
+#define OP_Destroy 137
+#define OP_Clear 138
+#define OP_ResetSorter 139
+#define OP_CreateBtree 140 /* synopsis: r[P2]=root iDb=P1 flags=P3 */
+#define OP_Real 141 /* same as TK_FLOAT, synopsis: r[P2]=P4 */
+#define OP_SqlExec 142
+#define OP_ParseSchema 143
+#define OP_LoadAnalysis 144
+#define OP_DropTable 145
+#define OP_DropIndex 146
+#define OP_DropTrigger 147
+#define OP_IntegrityCk 148
+#define OP_RowSetAdd 149 /* synopsis: rowset(P1)=r[P2] */
+#define OP_Param 150
+#define OP_FkCounter 151 /* synopsis: fkctr[P1]+=P2 */
+#define OP_MemMax 152 /* synopsis: r[P1]=max(r[P1],r[P2]) */
+#define OP_OffsetLimit 153 /* synopsis: if r[P1]>0 then r[P2]=r[P1]+max(0,r[P3]) else r[P2]=(-1) */
+#define OP_AggInverse 154 /* synopsis: accum=r[P3] inverse(r[P2@P5]) */
+#define OP_AggStep 155 /* synopsis: accum=r[P3] step(r[P2@P5]) */
+#define OP_AggStep1 156 /* synopsis: accum=r[P3] step(r[P2@P5]) */
+#define OP_AggValue 157 /* synopsis: r[P3]=value N=P2 */
+#define OP_AggFinal 158 /* synopsis: accum=r[P1] N=P2 */
+#define OP_Expire 159
+#define OP_TableLock 160 /* synopsis: iDb=P1 root=P2 write=P3 */
+#define OP_VBegin 161
+#define OP_VCreate 162
+#define OP_VDestroy 163
+#define OP_VOpen 164
+#define OP_VColumn 165 /* synopsis: r[P3]=vcolumn(P2) */
+#define OP_VRename 166
+#define OP_Pagecount 167
+#define OP_MaxPgcnt 168
+#define OP_Trace 169
+#define OP_CursorHint 170
+#define OP_Noop 171
+#define OP_Explain 172
+#define OP_Abortable 173
+
+/* Properties such as "out2" or "jump" that are specified in
+** comments following the "case" for each opcode in the vdbe.c
+** are encoded into bitvectors as follows:
+*/
+#define OPFLG_JUMP 0x01 /* jump: P2 holds jmp target */
+#define OPFLG_IN1 0x02 /* in1: P1 is an input */
+#define OPFLG_IN2 0x04 /* in2: P2 is an input */
+#define OPFLG_IN3 0x08 /* in3: P3 is an input */
+#define OPFLG_OUT2 0x10 /* out2: P2 is an output */
+#define OPFLG_OUT3 0x20 /* out3: P3 is an output */
+#define OPFLG_INITIALIZER {\
+/* 0 */ 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x00, 0x10,\
+/* 8 */ 0x00, 0x01, 0x00, 0x01, 0x01, 0x01, 0x03, 0x03,\
+/* 16 */ 0x01, 0x01, 0x03, 0x12, 0x03, 0x01, 0x09, 0x09,\
+/* 24 */ 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09,\
+/* 32 */ 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,\
+/* 40 */ 0x01, 0x23, 0x0b, 0x26, 0x26, 0x01, 0x01, 0x03,\
+/* 48 */ 0x03, 0x03, 0x03, 0x03, 0x0b, 0x0b, 0x0b, 0x0b,\
+/* 56 */ 0x0b, 0x0b, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00,\
+/* 64 */ 0x00, 0x00, 0x02, 0x02, 0x08, 0x00, 0x10, 0x10,\
+/* 72 */ 0x10, 0x10, 0x00, 0x10, 0x10, 0x00, 0x00, 0x10,\
+/* 80 */ 0x10, 0x00, 0x00, 0x02, 0x02, 0x02, 0x00, 0x00,\
+/* 88 */ 0x12, 0x20, 0x00, 0x00, 0x26, 0x26, 0x26, 0x26,\
+/* 96 */ 0x26, 0x26, 0x26, 0x26, 0x26, 0x26, 0x00, 0x12,\
+/* 104 */ 0x10, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00,\
+/* 112 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
+/* 120 */ 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
+/* 128 */ 0x00, 0x10, 0x00, 0x00, 0x04, 0x04, 0x00, 0x00,\
+/* 136 */ 0x10, 0x10, 0x00, 0x00, 0x10, 0x10, 0x00, 0x00,\
+/* 144 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x10, 0x00,\
+/* 152 */ 0x04, 0x1a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
+/* 160 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10,\
+/* 168 */ 0x10, 0x00, 0x00, 0x00, 0x00, 0x00,}
+
+/* The sqlite3P2Values() routine is able to run faster if it knows
+** the value of the largest JUMP opcode. The smaller the maximum
+** JUMP opcode the better, so the mkopcodeh.tcl script that
+** generated this include file strives to group all JUMP opcodes
+** together near the beginning of the list.
+*/
+#define SQLITE_MX_JUMP_OPCODE 61 /* Maximum JUMP opcode */
+
+/************** End of opcodes.h *********************************************/
+/************** Continuing where we left off in vdbe.h ***********************/
+
+/*
+** Additional non-public SQLITE_PREPARE_* flags
+*/
+#define SQLITE_PREPARE_SAVESQL 0x80 /* Preserve SQL text */
+#define SQLITE_PREPARE_MASK 0x0f /* Mask of public flags */
+
+/*
+** Prototypes for the VDBE interface. See comments on the implementation
+** for a description of what each of these routines does.
+*/
+SQLITE_PRIVATE Vdbe *sqlite3VdbeCreate(Parse*);
+SQLITE_PRIVATE int sqlite3VdbeAddOp0(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp1(Vdbe*,int,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
+SQLITE_PRIVATE int sqlite3VdbeGoto(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeLoadString(Vdbe*,int,const char*);
+SQLITE_PRIVATE void sqlite3VdbeMultiLoad(Vdbe*,int,const char*,...);
+SQLITE_PRIVATE int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp4Dup8(Vdbe*,int,int,int,int,const u8*,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
+SQLITE_PRIVATE void sqlite3VdbeEndCoroutine(Vdbe*,int);
+#if defined(SQLITE_DEBUG) && !defined(SQLITE_TEST_REALLOC_STRESS)
+SQLITE_PRIVATE void sqlite3VdbeVerifyNoMallocRequired(Vdbe *p, int N);
+SQLITE_PRIVATE void sqlite3VdbeVerifyNoResultRow(Vdbe *p);
+#else
+# define sqlite3VdbeVerifyNoMallocRequired(A,B)
+# define sqlite3VdbeVerifyNoResultRow(A)
+#endif
+#if defined(SQLITE_DEBUG)
+SQLITE_PRIVATE void sqlite3VdbeVerifyAbortable(Vdbe *p, int);
+#else
+# define sqlite3VdbeVerifyAbortable(A,B)
+#endif
+SQLITE_PRIVATE VdbeOp *sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp,int iLineno);
+#ifndef SQLITE_OMIT_EXPLAIN
+SQLITE_PRIVATE void sqlite3VdbeExplain(Parse*,u8,const char*,...);
+SQLITE_PRIVATE void sqlite3VdbeExplainPop(Parse*);
+SQLITE_PRIVATE int sqlite3VdbeExplainParent(Parse*);
+# define ExplainQueryPlan(P) sqlite3VdbeExplain P
+# define ExplainQueryPlanPop(P) sqlite3VdbeExplainPop(P)
+# define ExplainQueryPlanParent(P) sqlite3VdbeExplainParent(P)
+#else
+# define ExplainQueryPlan(P)
+# define ExplainQueryPlanPop(P)
+# define ExplainQueryPlanParent(P) 0
+#endif
+SQLITE_PRIVATE void sqlite3VdbeAddParseSchemaOp(Vdbe*,int,char*);
+SQLITE_PRIVATE void sqlite3VdbeChangeOpcode(Vdbe*, u32 addr, u8);
+SQLITE_PRIVATE void sqlite3VdbeChangeP1(Vdbe*, u32 addr, int P1);
+SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe*, u32 addr, int P2);
+SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe*, u32 addr, int P3);
+SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe*, u16 P5);
+SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe*, int addr);
+SQLITE_PRIVATE int sqlite3VdbeChangeToNoop(Vdbe*, int addr);
+SQLITE_PRIVATE int sqlite3VdbeDeletePriorOpcode(Vdbe*, u8 op);
+SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
+SQLITE_PRIVATE void sqlite3VdbeAppendP4(Vdbe*, void *pP4, int p4type);
+SQLITE_PRIVATE void sqlite3VdbeSetP4KeyInfo(Parse*, Index*);
+SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe*, int);
+SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
+SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeRunOnlyOnce(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeReusable(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeClearObject(sqlite3*,Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,Parse*);
+SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);
+SQLITE_PRIVATE int sqlite3VdbeCurrentAddr(Vdbe*);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3VdbeAssertMayAbort(Vdbe *, int);
+#endif
+SQLITE_PRIVATE void sqlite3VdbeResetStepResult(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeRewind(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeSetNumCols(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*));
+SQLITE_PRIVATE void sqlite3VdbeCountChanges(Vdbe*);
+SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe*);
+SQLITE_PRIVATE u8 sqlite3VdbePrepareFlags(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, u8);
+SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
+SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
+SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetBoundValue(Vdbe*, int, u8);
+SQLITE_PRIVATE void sqlite3VdbeSetVarmask(Vdbe*, int);
+#ifndef SQLITE_OMIT_TRACE
+SQLITE_PRIVATE char *sqlite3VdbeExpandSql(Vdbe*, const char*);
+#endif
+SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
+SQLITE_PRIVATE int sqlite3BlobCompare(const Mem*, const Mem*);
+
+SQLITE_PRIVATE void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
+SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
+SQLITE_PRIVATE int sqlite3VdbeRecordCompareWithSkip(int, const void *, UnpackedRecord *, int);
+SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo*);
+
+typedef int (*RecordCompare)(int,const void*,UnpackedRecord*);
+SQLITE_PRIVATE RecordCompare sqlite3VdbeFindCompare(UnpackedRecord*);
+
+#ifndef SQLITE_OMIT_TRIGGER
+SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
+#endif
+
+SQLITE_PRIVATE int sqlite3NotPureFunc(sqlite3_context*);
+
+/* Use SQLITE_ENABLE_COMMENTS to enable generation of extra comments on
+** each VDBE opcode.
+**
+** Use the SQLITE_ENABLE_MODULE_COMMENTS macro to see some extra no-op
+** comments in VDBE programs that show key decision points in the code
+** generator.
+*/
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
+SQLITE_PRIVATE void sqlite3VdbeComment(Vdbe*, const char*, ...);
+# define VdbeComment(X) sqlite3VdbeComment X
+SQLITE_PRIVATE void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
+# define VdbeNoopComment(X) sqlite3VdbeNoopComment X
+# ifdef SQLITE_ENABLE_MODULE_COMMENTS
+# define VdbeModuleComment(X) sqlite3VdbeNoopComment X
+# else
+# define VdbeModuleComment(X)
+# endif
+#else
+# define VdbeComment(X)
+# define VdbeNoopComment(X)
+# define VdbeModuleComment(X)
+#endif
+
+/*
+** The VdbeCoverage macros are used to set a coverage testing point
+** for VDBE branch instructions. The coverage testing points are line
+** numbers in the sqlite3.c source file. VDBE branch coverage testing
+** only works with an amalagmation build. That's ok since a VDBE branch
+** coverage build designed for testing the test suite only. No application
+** should ever ship with VDBE branch coverage measuring turned on.
+**
+** VdbeCoverage(v) // Mark the previously coded instruction
+** // as a branch
+**
+** VdbeCoverageIf(v, conditional) // Mark previous if conditional true
+**
+** VdbeCoverageAlwaysTaken(v) // Previous branch is always taken
+**
+** VdbeCoverageNeverTaken(v) // Previous branch is never taken
+**
+** VdbeCoverageNeverNull(v) // Previous three-way branch is only
+** // taken on the first two ways. The
+** // NULL option is not possible
+**
+** VdbeCoverageEqNe(v) // Previous OP_Jump is only interested
+** // in distingishing equal and not-equal.
+**
+** Every VDBE branch operation must be tagged with one of the macros above.
+** If not, then when "make test" is run with -DSQLITE_VDBE_COVERAGE and
+** -DSQLITE_DEBUG then an ALWAYS() will fail in the vdbeTakeBranch()
+** routine in vdbe.c, alerting the developer to the missed tag.
+**
+** During testing, the test application will invoke
+** sqlite3_test_control(SQLITE_TESTCTRL_VDBE_COVERAGE,...) to set a callback
+** routine that is invoked as each bytecode branch is taken. The callback
+** contains the sqlite3.c source line number ov the VdbeCoverage macro and
+** flags to indicate whether or not the branch was taken. The test application
+** is responsible for keeping track of this and reporting byte-code branches
+** that are never taken.
+**
+** See the VdbeBranchTaken() macro and vdbeTakeBranch() function in the
+** vdbe.c source file for additional information.
+*/
+#ifdef SQLITE_VDBE_COVERAGE
+SQLITE_PRIVATE void sqlite3VdbeSetLineNumber(Vdbe*,int);
+# define VdbeCoverage(v) sqlite3VdbeSetLineNumber(v,__LINE__)
+# define VdbeCoverageIf(v,x) if(x)sqlite3VdbeSetLineNumber(v,__LINE__)
+# define VdbeCoverageAlwaysTaken(v) \
+ sqlite3VdbeSetLineNumber(v,__LINE__|0x5000000);
+# define VdbeCoverageNeverTaken(v) \
+ sqlite3VdbeSetLineNumber(v,__LINE__|0x6000000);
+# define VdbeCoverageNeverNull(v) \
+ sqlite3VdbeSetLineNumber(v,__LINE__|0x4000000);
+# define VdbeCoverageNeverNullIf(v,x) \
+ if(x)sqlite3VdbeSetLineNumber(v,__LINE__|0x4000000);
+# define VdbeCoverageEqNe(v) \
+ sqlite3VdbeSetLineNumber(v,__LINE__|0x8000000);
+# define VDBE_OFFSET_LINENO(x) (__LINE__+x)
+#else
+# define VdbeCoverage(v)
+# define VdbeCoverageIf(v,x)
+# define VdbeCoverageAlwaysTaken(v)
+# define VdbeCoverageNeverTaken(v)
+# define VdbeCoverageNeverNull(v)
+# define VdbeCoverageNeverNullIf(v,x)
+# define VdbeCoverageEqNe(v)
+# define VDBE_OFFSET_LINENO(x) 0
+#endif
+
+#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
+SQLITE_PRIVATE void sqlite3VdbeScanStatus(Vdbe*, int, int, int, LogEst, const char*);
+#else
+# define sqlite3VdbeScanStatus(a,b,c,d,e)
+#endif
+
+#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
+SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, VdbeOp*);
+#endif
+
+#endif /* SQLITE_VDBE_H */
+
+/************** End of vdbe.h ************************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include pager.h in the middle of sqliteInt.h *****************/
+/************** Begin file pager.h *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the sqlite page cache
+** subsystem. The page cache subsystem reads and writes a file a page
+** at a time and provides a journal for rollback.
+*/
+
+#ifndef SQLITE_PAGER_H
+#define SQLITE_PAGER_H
+
+/*
+** Default maximum size for persistent journal files. A negative
+** value means no limit. This value may be overridden using the
+** sqlite3PagerJournalSizeLimit() API. See also "PRAGMA journal_size_limit".
+*/
+#ifndef SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT
+ #define SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT -1
+#endif
+
+/*
+** The type used to represent a page number. The first page in a file
+** is called page 1. 0 is used to represent "not a page".
+*/
+typedef u32 Pgno;
+
+/*
+** Each open file is managed by a separate instance of the "Pager" structure.
+*/
+typedef struct Pager Pager;
+
+/*
+** Handle type for pages.
+*/
+typedef struct PgHdr DbPage;
+
+/*
+** Page number PAGER_MJ_PGNO is never used in an SQLite database (it is
+** reserved for working around a windows/posix incompatibility). It is
+** used in the journal to signify that the remainder of the journal file
+** is devoted to storing a master journal name - there are no more pages to
+** roll back. See comments for function writeMasterJournal() in pager.c
+** for details.
+*/
+#define PAGER_MJ_PGNO(x) ((Pgno)((PENDING_BYTE/((x)->pageSize))+1))
+
+/*
+** Allowed values for the flags parameter to sqlite3PagerOpen().
+**
+** NOTE: These values must match the corresponding BTREE_ values in btree.h.
+*/
+#define PAGER_OMIT_JOURNAL 0x0001 /* Do not use a rollback journal */
+#define PAGER_MEMORY 0x0002 /* In-memory database */
+
+/*
+** Valid values for the second argument to sqlite3PagerLockingMode().
+*/
+#define PAGER_LOCKINGMODE_QUERY -1
+#define PAGER_LOCKINGMODE_NORMAL 0
+#define PAGER_LOCKINGMODE_EXCLUSIVE 1
+
+/*
+** Numeric constants that encode the journalmode.
+**
+** The numeric values encoded here (other than PAGER_JOURNALMODE_QUERY)
+** are exposed in the API via the "PRAGMA journal_mode" command and
+** therefore cannot be changed without a compatibility break.
+*/
+#define PAGER_JOURNALMODE_QUERY (-1) /* Query the value of journalmode */
+#define PAGER_JOURNALMODE_DELETE 0 /* Commit by deleting journal file */
+#define PAGER_JOURNALMODE_PERSIST 1 /* Commit by zeroing journal header */
+#define PAGER_JOURNALMODE_OFF 2 /* Journal omitted. */
+#define PAGER_JOURNALMODE_TRUNCATE 3 /* Commit by truncating journal */
+#define PAGER_JOURNALMODE_MEMORY 4 /* In-memory journal file */
+#define PAGER_JOURNALMODE_WAL 5 /* Use write-ahead logging */
+
+/*
+** Flags that make up the mask passed to sqlite3PagerGet().
+*/
+#define PAGER_GET_NOCONTENT 0x01 /* Do not load data from disk */
+#define PAGER_GET_READONLY 0x02 /* Read-only page is acceptable */
+
+/*
+** Flags for sqlite3PagerSetFlags()
+**
+** Value constraints (enforced via assert()):
+** PAGER_FULLFSYNC == SQLITE_FullFSync
+** PAGER_CKPT_FULLFSYNC == SQLITE_CkptFullFSync
+** PAGER_CACHE_SPILL == SQLITE_CacheSpill
+*/
+#define PAGER_SYNCHRONOUS_OFF 0x01 /* PRAGMA synchronous=OFF */
+#define PAGER_SYNCHRONOUS_NORMAL 0x02 /* PRAGMA synchronous=NORMAL */
+#define PAGER_SYNCHRONOUS_FULL 0x03 /* PRAGMA synchronous=FULL */
+#define PAGER_SYNCHRONOUS_EXTRA 0x04 /* PRAGMA synchronous=EXTRA */
+#define PAGER_SYNCHRONOUS_MASK 0x07 /* Mask for four values above */
+#define PAGER_FULLFSYNC 0x08 /* PRAGMA fullfsync=ON */
+#define PAGER_CKPT_FULLFSYNC 0x10 /* PRAGMA checkpoint_fullfsync=ON */
+#define PAGER_CACHESPILL 0x20 /* PRAGMA cache_spill=ON */
+#define PAGER_FLAGS_MASK 0x38 /* All above except SYNCHRONOUS */
+
+/*
+** The remainder of this file contains the declarations of the functions
+** that make up the Pager sub-system API. See source code comments for
+** a detailed description of each routine.
+*/
+
+/* Open and close a Pager connection. */
+SQLITE_PRIVATE int sqlite3PagerOpen(
+ sqlite3_vfs*,
+ Pager **ppPager,
+ const char*,
+ int,
+ int,
+ int,
+ void(*)(DbPage*)
+);
+SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager, sqlite3*);
+SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager*, int, unsigned char*);
+
+/* Functions used to configure a Pager object. */
+SQLITE_PRIVATE void sqlite3PagerSetBusyHandler(Pager*, int(*)(void *), void *);
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u32*, int);
+#ifdef SQLITE_HAS_CODEC
+SQLITE_PRIVATE void sqlite3PagerAlignReserve(Pager*,Pager*);
+#endif
+SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
+SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
+SQLITE_PRIVATE int sqlite3PagerSetSpillsize(Pager*, int);
+SQLITE_PRIVATE void sqlite3PagerSetMmapLimit(Pager *, sqlite3_int64);
+SQLITE_PRIVATE void sqlite3PagerShrink(Pager*);
+SQLITE_PRIVATE void sqlite3PagerSetFlags(Pager*,unsigned);
+SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *, int);
+SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *, int);
+SQLITE_PRIVATE int sqlite3PagerGetJournalMode(Pager*);
+SQLITE_PRIVATE int sqlite3PagerOkToChangeJournalMode(Pager*);
+SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *, i64);
+SQLITE_PRIVATE sqlite3_backup **sqlite3PagerBackupPtr(Pager*);
+SQLITE_PRIVATE int sqlite3PagerFlush(Pager*);
+
+/* Functions used to obtain and release page references. */
+SQLITE_PRIVATE int sqlite3PagerGet(Pager *pPager, Pgno pgno, DbPage **ppPage, int clrFlag);
+SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno);
+SQLITE_PRIVATE void sqlite3PagerRef(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerUnref(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerUnrefNotNull(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerUnrefPageOne(DbPage*);
+
+/* Operations on page references. */
+SQLITE_PRIVATE int sqlite3PagerWrite(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerDontWrite(DbPage*);
+SQLITE_PRIVATE int sqlite3PagerMovepage(Pager*,DbPage*,Pgno,int);
+SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage*);
+SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *);
+SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *);
+
+/* Functions used to manage pager transactions and savepoints. */
+SQLITE_PRIVATE void sqlite3PagerPagecount(Pager*, int*);
+SQLITE_PRIVATE int sqlite3PagerBegin(Pager*, int exFlag, int);
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);
+SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager*);
+SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager, const char *zMaster);
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager*);
+SQLITE_PRIVATE int sqlite3PagerRollback(Pager*);
+SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
+SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
+SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager);
+
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE int sqlite3PagerCheckpoint(Pager *pPager, sqlite3*, int, int*, int*);
+SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager);
+SQLITE_PRIVATE int sqlite3PagerWalCallback(Pager *pPager);
+SQLITE_PRIVATE int sqlite3PagerOpenWal(Pager *pPager, int *pisOpen);
+SQLITE_PRIVATE int sqlite3PagerCloseWal(Pager *pPager, sqlite3*);
+# ifdef SQLITE_DIRECT_OVERFLOW_READ
+SQLITE_PRIVATE int sqlite3PagerUseWal(Pager *pPager, Pgno);
+# endif
+# ifdef SQLITE_ENABLE_SNAPSHOT
+SQLITE_PRIVATE int sqlite3PagerSnapshotGet(Pager *pPager, sqlite3_snapshot **ppSnapshot);
+SQLITE_PRIVATE int sqlite3PagerSnapshotOpen(Pager *pPager, sqlite3_snapshot *pSnapshot);
+SQLITE_PRIVATE int sqlite3PagerSnapshotRecover(Pager *pPager);
+SQLITE_PRIVATE int sqlite3PagerSnapshotCheck(Pager *pPager, sqlite3_snapshot *pSnapshot);
+SQLITE_PRIVATE void sqlite3PagerSnapshotUnlock(Pager *pPager);
+# endif
+#else
+# define sqlite3PagerUseWal(x,y) 0
+#endif
+
+#ifdef SQLITE_ENABLE_ZIPVFS
+SQLITE_PRIVATE int sqlite3PagerWalFramesize(Pager *pPager);
+#endif
+
+/* Functions used to query pager state and configuration. */
+SQLITE_PRIVATE u8 sqlite3PagerIsreadonly(Pager*);
+SQLITE_PRIVATE u32 sqlite3PagerDataVersion(Pager*);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3PagerRefcount(Pager*);
+#endif
+SQLITE_PRIVATE int sqlite3PagerMemUsed(Pager*);
+SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager*, int);
+SQLITE_PRIVATE sqlite3_vfs *sqlite3PagerVfs(Pager*);
+SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager*);
+SQLITE_PRIVATE sqlite3_file *sqlite3PagerJrnlFile(Pager*);
+SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager*);
+SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager*);
+SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager*);
+SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *, int, int, int *);
+SQLITE_PRIVATE void sqlite3PagerClearCache(Pager*);
+SQLITE_PRIVATE int sqlite3SectorSize(sqlite3_file *);
+#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
+SQLITE_PRIVATE void sqlite3PagerResetLockTimeout(Pager *pPager);
+#else
+# define sqlite3PagerResetLockTimeout(X)
+#endif
+
+/* Functions used to truncate the database file. */
+SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager*,Pgno);
+
+SQLITE_PRIVATE void sqlite3PagerRekey(DbPage*, Pgno, u16);
+
+#if defined(SQLITE_HAS_CODEC) && !defined(SQLITE_OMIT_WAL)
+SQLITE_PRIVATE void *sqlite3PagerCodec(DbPage *);
+#endif
+
+/* Functions to support testing and debugging. */
+#if !defined(NDEBUG) || defined(SQLITE_TEST)
+SQLITE_PRIVATE Pgno sqlite3PagerPagenumber(DbPage*);
+SQLITE_PRIVATE int sqlite3PagerIswriteable(DbPage*);
+#endif
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int *sqlite3PagerStats(Pager*);
+SQLITE_PRIVATE void sqlite3PagerRefdump(Pager*);
+ void disable_simulated_io_errors(void);
+ void enable_simulated_io_errors(void);
+#else
+# define disable_simulated_io_errors()
+# define enable_simulated_io_errors()
+#endif
+
+#endif /* SQLITE_PAGER_H */
+
+/************** End of pager.h ***********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include pcache.h in the middle of sqliteInt.h ****************/
+/************** Begin file pcache.h ******************************************/
+/*
+** 2008 August 05
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the sqlite page cache
+** subsystem.
+*/
+
+#ifndef _PCACHE_H_
+
+typedef struct PgHdr PgHdr;
+typedef struct PCache PCache;
+
+/*
+** Every page in the cache is controlled by an instance of the following
+** structure.
+*/
+struct PgHdr {
+ sqlite3_pcache_page *pPage; /* Pcache object page handle */
+ void *pData; /* Page data */
+ void *pExtra; /* Extra content */
+ PCache *pCache; /* PRIVATE: Cache that owns this page */
+ PgHdr *pDirty; /* Transient list of dirty sorted by pgno */
+ Pager *pPager; /* The pager this page is part of */
+ Pgno pgno; /* Page number for this page */
+#ifdef SQLITE_CHECK_PAGES
+ u32 pageHash; /* Hash of page content */
+#endif
+ u16 flags; /* PGHDR flags defined below */
+
+ /**********************************************************************
+ ** Elements above, except pCache, are public. All that follow are
+ ** private to pcache.c and should not be accessed by other modules.
+ ** pCache is grouped with the public elements for efficiency.
+ */
+ i16 nRef; /* Number of users of this page */
+ PgHdr *pDirtyNext; /* Next element in list of dirty pages */
+ PgHdr *pDirtyPrev; /* Previous element in list of dirty pages */
+ /* NB: pDirtyNext and pDirtyPrev are undefined if the
+ ** PgHdr object is not dirty */
+};
+
+/* Bit values for PgHdr.flags */
+#define PGHDR_CLEAN 0x001 /* Page not on the PCache.pDirty list */
+#define PGHDR_DIRTY 0x002 /* Page is on the PCache.pDirty list */
+#define PGHDR_WRITEABLE 0x004 /* Journaled and ready to modify */
+#define PGHDR_NEED_SYNC 0x008 /* Fsync the rollback journal before
+ ** writing this page to the database */
+#define PGHDR_DONT_WRITE 0x010 /* Do not write content to disk */
+#define PGHDR_MMAP 0x020 /* This is an mmap page object */
+
+#define PGHDR_WAL_APPEND 0x040 /* Appended to wal file */
+
+/* Initialize and shutdown the page cache subsystem */
+SQLITE_PRIVATE int sqlite3PcacheInitialize(void);
+SQLITE_PRIVATE void sqlite3PcacheShutdown(void);
+
+/* Page cache buffer management:
+** These routines implement SQLITE_CONFIG_PAGECACHE.
+*/
+SQLITE_PRIVATE void sqlite3PCacheBufferSetup(void *, int sz, int n);
+
+/* Create a new pager cache.
+** Under memory stress, invoke xStress to try to make pages clean.
+** Only clean and unpinned pages can be reclaimed.
+*/
+SQLITE_PRIVATE int sqlite3PcacheOpen(
+ int szPage, /* Size of every page */
+ int szExtra, /* Extra space associated with each page */
+ int bPurgeable, /* True if pages are on backing store */
+ int (*xStress)(void*, PgHdr*), /* Call to try to make pages clean */
+ void *pStress, /* Argument to xStress */
+ PCache *pToInit /* Preallocated space for the PCache */
+);
+
+/* Modify the page-size after the cache has been created. */
+SQLITE_PRIVATE int sqlite3PcacheSetPageSize(PCache *, int);
+
+/* Return the size in bytes of a PCache object. Used to preallocate
+** storage space.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSize(void);
+
+/* One release per successful fetch. Page is pinned until released.
+** Reference counted.
+*/
+SQLITE_PRIVATE sqlite3_pcache_page *sqlite3PcacheFetch(PCache*, Pgno, int createFlag);
+SQLITE_PRIVATE int sqlite3PcacheFetchStress(PCache*, Pgno, sqlite3_pcache_page**);
+SQLITE_PRIVATE PgHdr *sqlite3PcacheFetchFinish(PCache*, Pgno, sqlite3_pcache_page *pPage);
+SQLITE_PRIVATE void sqlite3PcacheRelease(PgHdr*);
+
+SQLITE_PRIVATE void sqlite3PcacheDrop(PgHdr*); /* Remove page from cache */
+SQLITE_PRIVATE void sqlite3PcacheMakeDirty(PgHdr*); /* Make sure page is marked dirty */
+SQLITE_PRIVATE void sqlite3PcacheMakeClean(PgHdr*); /* Mark a single page as clean */
+SQLITE_PRIVATE void sqlite3PcacheCleanAll(PCache*); /* Mark all dirty list pages as clean */
+SQLITE_PRIVATE void sqlite3PcacheClearWritable(PCache*);
+
+/* Change a page number. Used by incr-vacuum. */
+SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr*, Pgno);
+
+/* Remove all pages with pgno>x. Reset the cache if x==0 */
+SQLITE_PRIVATE void sqlite3PcacheTruncate(PCache*, Pgno x);
+
+/* Get a list of all dirty pages in the cache, sorted by page number */
+SQLITE_PRIVATE PgHdr *sqlite3PcacheDirtyList(PCache*);
+
+/* Reset and close the cache object */
+SQLITE_PRIVATE void sqlite3PcacheClose(PCache*);
+
+/* Clear flags from pages of the page cache */
+SQLITE_PRIVATE void sqlite3PcacheClearSyncFlags(PCache *);
+
+/* Discard the contents of the cache */
+SQLITE_PRIVATE void sqlite3PcacheClear(PCache*);
+
+/* Return the total number of outstanding page references */
+SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache*);
+
+/* Increment the reference count of an existing page */
+SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr*);
+
+SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr*);
+
+/* Return the total number of pages stored in the cache */
+SQLITE_PRIVATE int sqlite3PcachePagecount(PCache*);
+
+#if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
+/* Iterate through all dirty pages currently stored in the cache. This
+** interface is only available if SQLITE_CHECK_PAGES is defined when the
+** library is built.
+*/
+SQLITE_PRIVATE void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *));
+#endif
+
+#if defined(SQLITE_DEBUG)
+/* Check invariants on a PgHdr object */
+SQLITE_PRIVATE int sqlite3PcachePageSanity(PgHdr*);
+#endif
+
+/* Set and get the suggested cache-size for the specified pager-cache.
+**
+** If no global maximum is configured, then the system attempts to limit
+** the total number of pages cached by purgeable pager-caches to the sum
+** of the suggested cache-sizes.
+*/
+SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *, int);
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *);
+#endif
+
+/* Set or get the suggested spill-size for the specified pager-cache.
+**
+** The spill-size is the minimum number of pages in cache before the cache
+** will attempt to spill dirty pages by calling xStress.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSetSpillsize(PCache *, int);
+
+/* Free up as much memory as possible from the page cache */
+SQLITE_PRIVATE void sqlite3PcacheShrink(PCache*);
+
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/* Try to return memory used by the pcache module to the main memory heap */
+SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int);
+#endif
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE void sqlite3PcacheStats(int*,int*,int*,int*);
+#endif
+
+SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
+
+/* Return the header size */
+SQLITE_PRIVATE int sqlite3HeaderSizePcache(void);
+SQLITE_PRIVATE int sqlite3HeaderSizePcache1(void);
+
+/* Number of dirty pages as a percentage of the configured cache size */
+SQLITE_PRIVATE int sqlite3PCachePercentDirty(PCache*);
+
+#endif /* _PCACHE_H_ */
+
+/************** End of pcache.h **********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include os.h in the middle of sqliteInt.h ********************/
+/************** Begin file os.h **********************************************/
+/*
+** 2001 September 16
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This header file (together with is companion C source-code file
+** "os.c") attempt to abstract the underlying operating system so that
+** the SQLite library will work on both POSIX and windows systems.
+**
+** This header file is #include-ed by sqliteInt.h and thus ends up
+** being included by every source file.
+*/
+#ifndef _SQLITE_OS_H_
+#define _SQLITE_OS_H_
+
+/*
+** Attempt to automatically detect the operating system and setup the
+** necessary pre-processor macros for it.
+*/
+/************** Include os_setup.h in the middle of os.h *********************/
+/************** Begin file os_setup.h ****************************************/
+/*
+** 2013 November 25
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains pre-processor directives related to operating system
+** detection and/or setup.
+*/
+#ifndef SQLITE_OS_SETUP_H
+#define SQLITE_OS_SETUP_H
+
+/*
+** Figure out if we are dealing with Unix, Windows, or some other operating
+** system.
+**
+** After the following block of preprocess macros, all of SQLITE_OS_UNIX,
+** SQLITE_OS_WIN, and SQLITE_OS_OTHER will defined to either 1 or 0. One of
+** the three will be 1. The other two will be 0.
+*/
+#if defined(SQLITE_OS_OTHER)
+# if SQLITE_OS_OTHER==1
+# undef SQLITE_OS_UNIX
+# define SQLITE_OS_UNIX 0
+# undef SQLITE_OS_WIN
+# define SQLITE_OS_WIN 0
+# else
+# undef SQLITE_OS_OTHER
+# endif
+#endif
+#if !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_OTHER)
+# define SQLITE_OS_OTHER 0
+# ifndef SQLITE_OS_WIN
+# if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || \
+ defined(__MINGW32__) || defined(__BORLANDC__)
+# define SQLITE_OS_WIN 1
+# define SQLITE_OS_UNIX 0
+# else
+# define SQLITE_OS_WIN 0
+# define SQLITE_OS_UNIX 1
+# endif
+# else
+# define SQLITE_OS_UNIX 0
+# endif
+#else
+# ifndef SQLITE_OS_WIN
+# define SQLITE_OS_WIN 0
+# endif
+#endif
+
+#endif /* SQLITE_OS_SETUP_H */
+
+/************** End of os_setup.h ********************************************/
+/************** Continuing where we left off in os.h *************************/
+
+/* If the SET_FULLSYNC macro is not defined above, then make it
+** a no-op
+*/
+#ifndef SET_FULLSYNC
+# define SET_FULLSYNC(x,y)
+#endif
+
+/*
+** The default size of a disk sector
+*/
+#ifndef SQLITE_DEFAULT_SECTOR_SIZE
+# define SQLITE_DEFAULT_SECTOR_SIZE 4096
+#endif
+
+/*
+** Temporary files are named starting with this prefix followed by 16 random
+** alphanumeric characters, and no file extension. They are stored in the
+** OS's standard temporary file directory, and are deleted prior to exit.
+** If sqlite is being embedded in another program, you may wish to change the
+** prefix to reflect your program's name, so that if your program exits
+** prematurely, old temporary files can be easily identified. This can be done
+** using -DSQLITE_TEMP_FILE_PREFIX=myprefix_ on the compiler command line.
+**
+** 2006-10-31: The default prefix used to be "sqlite_". But then
+** Mcafee started using SQLite in their anti-virus product and it
+** started putting files with the "sqlite" name in the c:/temp folder.
+** This annoyed many windows users. Those users would then do a
+** Google search for "sqlite", find the telephone numbers of the
+** developers and call to wake them up at night and complain.
+** For this reason, the default name prefix is changed to be "sqlite"
+** spelled backwards. So the temp files are still identified, but
+** anybody smart enough to figure out the code is also likely smart
+** enough to know that calling the developer will not help get rid
+** of the file.
+*/
+#ifndef SQLITE_TEMP_FILE_PREFIX
+# define SQLITE_TEMP_FILE_PREFIX "etilqs_"
+#endif
+
+/*
+** The following values may be passed as the second argument to
+** sqlite3OsLock(). The various locks exhibit the following semantics:
+**
+** SHARED: Any number of processes may hold a SHARED lock simultaneously.
+** RESERVED: A single process may hold a RESERVED lock on a file at
+** any time. Other processes may hold and obtain new SHARED locks.
+** PENDING: A single process may hold a PENDING lock on a file at
+** any one time. Existing SHARED locks may persist, but no new
+** SHARED locks may be obtained by other processes.
+** EXCLUSIVE: An EXCLUSIVE lock precludes all other locks.
+**
+** PENDING_LOCK may not be passed directly to sqlite3OsLock(). Instead, a
+** process that requests an EXCLUSIVE lock may actually obtain a PENDING
+** lock. This can be upgraded to an EXCLUSIVE lock by a subsequent call to
+** sqlite3OsLock().
+*/
+#define NO_LOCK 0
+#define SHARED_LOCK 1
+#define RESERVED_LOCK 2
+#define PENDING_LOCK 3
+#define EXCLUSIVE_LOCK 4
+
+/*
+** File Locking Notes: (Mostly about windows but also some info for Unix)
+**
+** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
+** those functions are not available. So we use only LockFile() and
+** UnlockFile().
+**
+** LockFile() prevents not just writing but also reading by other processes.
+** A SHARED_LOCK is obtained by locking a single randomly-chosen
+** byte out of a specific range of bytes. The lock byte is obtained at
+** random so two separate readers can probably access the file at the
+** same time, unless they are unlucky and choose the same lock byte.
+** An EXCLUSIVE_LOCK is obtained by locking all bytes in the range.
+** There can only be one writer. A RESERVED_LOCK is obtained by locking
+** a single byte of the file that is designated as the reserved lock byte.
+** A PENDING_LOCK is obtained by locking a designated byte different from
+** the RESERVED_LOCK byte.
+**
+** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
+** which means we can use reader/writer locks. When reader/writer locks
+** are used, the lock is placed on the same range of bytes that is used
+** for probabilistic locking in Win95/98/ME. Hence, the locking scheme
+** will support two or more Win95 readers or two or more WinNT readers.
+** But a single Win95 reader will lock out all WinNT readers and a single
+** WinNT reader will lock out all other Win95 readers.
+**
+** The following #defines specify the range of bytes used for locking.
+** SHARED_SIZE is the number of bytes available in the pool from which
+** a random byte is selected for a shared lock. The pool of bytes for
+** shared locks begins at SHARED_FIRST.
+**
+** The same locking strategy and
+** byte ranges are used for Unix. This leaves open the possibility of having
+** clients on win95, winNT, and unix all talking to the same shared file
+** and all locking correctly. To do so would require that samba (or whatever
+** tool is being used for file sharing) implements locks correctly between
+** windows and unix. I'm guessing that isn't likely to happen, but by
+** using the same locking range we are at least open to the possibility.
+**
+** Locking in windows is manditory. For this reason, we cannot store
+** actual data in the bytes used for locking. The pager never allocates
+** the pages involved in locking therefore. SHARED_SIZE is selected so
+** that all locks will fit on a single page even at the minimum page size.
+** PENDING_BYTE defines the beginning of the locks. By default PENDING_BYTE
+** is set high so that we don't have to allocate an unused page except
+** for very large databases. But one should test the page skipping logic
+** by setting PENDING_BYTE low and running the entire regression suite.
+**
+** Changing the value of PENDING_BYTE results in a subtly incompatible
+** file format. Depending on how it is changed, you might not notice
+** the incompatibility right away, even running a full regression test.
+** The default location of PENDING_BYTE is the first byte past the
+** 1GB boundary.
+**
+*/
+#ifdef SQLITE_OMIT_WSD
+# define PENDING_BYTE (0x40000000)
+#else
+# define PENDING_BYTE sqlite3PendingByte
+#endif
+#define RESERVED_BYTE (PENDING_BYTE+1)
+#define SHARED_FIRST (PENDING_BYTE+2)
+#define SHARED_SIZE 510
+
+/*
+** Wrapper around OS specific sqlite3_os_init() function.
+*/
+SQLITE_PRIVATE int sqlite3OsInit(void);
+
+/*
+** Functions for accessing sqlite3_file methods
+*/
+SQLITE_PRIVATE void sqlite3OsClose(sqlite3_file*);
+SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file*, void*, int amt, i64 offset);
+SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file*, const void*, int amt, i64 offset);
+SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file*, i64 size);
+SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file*, int);
+SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file*, i64 *pSize);
+SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file*, int);
+SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file*, int);
+SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut);
+SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file*,int,void*);
+SQLITE_PRIVATE void sqlite3OsFileControlHint(sqlite3_file*,int,void*);
+#define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
+SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
+SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int, int, int);
+SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int);
+#endif /* SQLITE_OMIT_WAL */
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64, int, void **);
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *, i64, void *);
+
+
+/*
+** Functions for accessing sqlite3_vfs methods
+*/
+SQLITE_PRIVATE int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
+SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
+SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut);
+SQLITE_PRIVATE int sqlite3OsFullPathname(sqlite3_vfs *, const char *, int, char *);
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
+SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *, int, char *);
+SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *, void *, const char *))(void);
+SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *, void *);
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
+SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
+SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *, int);
+SQLITE_PRIVATE int sqlite3OsGetLastError(sqlite3_vfs*);
+SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *, sqlite3_int64*);
+
+/*
+** Convenience functions for opening and closing files using
+** sqlite3_malloc() to obtain space for the file-handle structure.
+*/
+SQLITE_PRIVATE int sqlite3OsOpenMalloc(sqlite3_vfs *, const char *, sqlite3_file **, int,int*);
+SQLITE_PRIVATE void sqlite3OsCloseFree(sqlite3_file *);
+
+#endif /* _SQLITE_OS_H_ */
+
+/************** End of os.h **************************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include mutex.h in the middle of sqliteInt.h *****************/
+/************** Begin file mutex.h *******************************************/
+/*
+** 2007 August 28
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains the common header for all mutex implementations.
+** The sqliteInt.h header #includes this file so that it is available
+** to all source files. We break it out in an effort to keep the code
+** better organized.
+**
+** NOTE: source files should *not* #include this header file directly.
+** Source files should #include the sqliteInt.h file and let that file
+** include this one indirectly.
+*/
+
+
+/*
+** Figure out what version of the code to use. The choices are
+**
+** SQLITE_MUTEX_OMIT No mutex logic. Not even stubs. The
+** mutexes implementation cannot be overridden
+** at start-time.
+**
+** SQLITE_MUTEX_NOOP For single-threaded applications. No
+** mutual exclusion is provided. But this
+** implementation can be overridden at
+** start-time.
+**
+** SQLITE_MUTEX_PTHREADS For multi-threaded applications on Unix.
+**
+** SQLITE_MUTEX_W32 For multi-threaded applications on Win32.
+*/
+#if !SQLITE_THREADSAFE
+# define SQLITE_MUTEX_OMIT
+#endif
+#if SQLITE_THREADSAFE && !defined(SQLITE_MUTEX_NOOP)
+# if SQLITE_OS_UNIX
+# define SQLITE_MUTEX_PTHREADS
+# elif SQLITE_OS_WIN
+# define SQLITE_MUTEX_W32
+# else
+# define SQLITE_MUTEX_NOOP
+# endif
+#endif
+
+#ifdef SQLITE_MUTEX_OMIT
+/*
+** If this is a no-op implementation, implement everything as macros.
+*/
+#define sqlite3_mutex_alloc(X) ((sqlite3_mutex*)8)
+#define sqlite3_mutex_free(X)
+#define sqlite3_mutex_enter(X)
+#define sqlite3_mutex_try(X) SQLITE_OK
+#define sqlite3_mutex_leave(X)
+#define sqlite3_mutex_held(X) ((void)(X),1)
+#define sqlite3_mutex_notheld(X) ((void)(X),1)
+#define sqlite3MutexAlloc(X) ((sqlite3_mutex*)8)
+#define sqlite3MutexInit() SQLITE_OK
+#define sqlite3MutexEnd()
+#define MUTEX_LOGIC(X)
+#else
+#define MUTEX_LOGIC(X) X
+#endif /* defined(SQLITE_MUTEX_OMIT) */
+
+/************** End of mutex.h ***********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+
+/* The SQLITE_EXTRA_DURABLE compile-time option used to set the default
+** synchronous setting to EXTRA. It is no longer supported.
+*/
+#ifdef SQLITE_EXTRA_DURABLE
+# warning Use SQLITE_DEFAULT_SYNCHRONOUS=3 instead of SQLITE_EXTRA_DURABLE
+# define SQLITE_DEFAULT_SYNCHRONOUS 3
+#endif
+
+/*
+** Default synchronous levels.
+**
+** Note that (for historcal reasons) the PAGER_SYNCHRONOUS_* macros differ
+** from the SQLITE_DEFAULT_SYNCHRONOUS value by 1.
+**
+** PAGER_SYNCHRONOUS DEFAULT_SYNCHRONOUS
+** OFF 1 0
+** NORMAL 2 1
+** FULL 3 2
+** EXTRA 4 3
+**
+** The "PRAGMA synchronous" statement also uses the zero-based numbers.
+** In other words, the zero-based numbers are used for all external interfaces
+** and the one-based values are used internally.
+*/
+#ifndef SQLITE_DEFAULT_SYNCHRONOUS
+# define SQLITE_DEFAULT_SYNCHRONOUS 2
+#endif
+#ifndef SQLITE_DEFAULT_WAL_SYNCHRONOUS
+# define SQLITE_DEFAULT_WAL_SYNCHRONOUS SQLITE_DEFAULT_SYNCHRONOUS
+#endif
+
+/*
+** Each database file to be accessed by the system is an instance
+** of the following structure. There are normally two of these structures
+** in the sqlite.aDb[] array. aDb[0] is the main database file and
+** aDb[1] is the database file used to hold temporary tables. Additional
+** databases may be attached.
+*/
+struct Db {
+ char *zDbSName; /* Name of this database. (schema name, not filename) */
+ Btree *pBt; /* The B*Tree structure for this database file */
+ u8 safety_level; /* How aggressive at syncing data to disk */
+ u8 bSyncSet; /* True if "PRAGMA synchronous=N" has been run */
+ Schema *pSchema; /* Pointer to database schema (possibly shared) */
+};
+
+/*
+** An instance of the following structure stores a database schema.
+**
+** Most Schema objects are associated with a Btree. The exception is
+** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
+** In shared cache mode, a single Schema object can be shared by multiple
+** Btrees that refer to the same underlying BtShared object.
+**
+** Schema objects are automatically deallocated when the last Btree that
+** references them is destroyed. The TEMP Schema is manually freed by
+** sqlite3_close().
+*
+** A thread must be holding a mutex on the corresponding Btree in order
+** to access Schema content. This implies that the thread must also be
+** holding a mutex on the sqlite3 connection pointer that owns the Btree.
+** For a TEMP Schema, only the connection mutex is required.
+*/
+struct Schema {
+ int schema_cookie; /* Database schema version number for this file */
+ int iGeneration; /* Generation counter. Incremented with each change */
+ Hash tblHash; /* All tables indexed by name */
+ Hash idxHash; /* All (named) indices indexed by name */
+ Hash trigHash; /* All triggers indexed by name */
+ Hash fkeyHash; /* All foreign keys by referenced table name */
+ Table *pSeqTab; /* The sqlite_sequence table used by AUTOINCREMENT */
+ u8 file_format; /* Schema format version for this file */
+ u8 enc; /* Text encoding used by this database */
+ u16 schemaFlags; /* Flags associated with this schema */
+ int cache_size; /* Number of pages to use in the cache */
+};
+
+/*
+** These macros can be used to test, set, or clear bits in the
+** Db.pSchema->flags field.
+*/
+#define DbHasProperty(D,I,P) (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))
+#define DbHasAnyProperty(D,I,P) (((D)->aDb[I].pSchema->schemaFlags&(P))!=0)
+#define DbSetProperty(D,I,P) (D)->aDb[I].pSchema->schemaFlags|=(P)
+#define DbClearProperty(D,I,P) (D)->aDb[I].pSchema->schemaFlags&=~(P)
+
+/*
+** Allowed values for the DB.pSchema->flags field.
+**
+** The DB_SchemaLoaded flag is set after the database schema has been
+** read into internal hash tables.
+**
+** DB_UnresetViews means that one or more views have column names that
+** have been filled out. If the schema changes, these column names might
+** changes and so the view will need to be reset.
+*/
+#define DB_SchemaLoaded 0x0001 /* The schema has been loaded */
+#define DB_UnresetViews 0x0002 /* Some views have defined column names */
+#define DB_Empty 0x0004 /* The file is empty (length 0 bytes) */
+#define DB_ResetWanted 0x0008 /* Reset the schema when nSchemaLock==0 */
+
+/*
+** The number of different kinds of things that can be limited
+** using the sqlite3_limit() interface.
+*/
+#define SQLITE_N_LIMIT (SQLITE_LIMIT_WORKER_THREADS+1)
+
+/*
+** Lookaside malloc is a set of fixed-size buffers that can be used
+** to satisfy small transient memory allocation requests for objects
+** associated with a particular database connection. The use of
+** lookaside malloc provides a significant performance enhancement
+** (approx 10%) by avoiding numerous malloc/free requests while parsing
+** SQL statements.
+**
+** The Lookaside structure holds configuration information about the
+** lookaside malloc subsystem. Each available memory allocation in
+** the lookaside subsystem is stored on a linked list of LookasideSlot
+** objects.
+**
+** Lookaside allocations are only allowed for objects that are associated
+** with a particular database connection. Hence, schema information cannot
+** be stored in lookaside because in shared cache mode the schema information
+** is shared by multiple database connections. Therefore, while parsing
+** schema information, the Lookaside.bEnabled flag is cleared so that
+** lookaside allocations are not used to construct the schema objects.
+*/
+struct Lookaside {
+ u32 bDisable; /* Only operate the lookaside when zero */
+ u16 sz; /* Size of each buffer in bytes */
+ u8 bMalloced; /* True if pStart obtained from sqlite3_malloc() */
+ u32 nSlot; /* Number of lookaside slots allocated */
+ u32 anStat[3]; /* 0: hits. 1: size misses. 2: full misses */
+ LookasideSlot *pInit; /* List of buffers not previously used */
+ LookasideSlot *pFree; /* List of available buffers */
+ void *pStart; /* First byte of available memory space */
+ void *pEnd; /* First byte past end of available space */
+};
+struct LookasideSlot {
+ LookasideSlot *pNext; /* Next buffer in the list of free buffers */
+};
+
+/*
+** A hash table for built-in function definitions. (Application-defined
+** functions use a regular table table from hash.h.)
+**
+** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
+** Collisions are on the FuncDef.u.pHash chain.
+*/
+#define SQLITE_FUNC_HASH_SZ 23
+struct FuncDefHash {
+ FuncDef *a[SQLITE_FUNC_HASH_SZ]; /* Hash table for functions */
+};
+
+#ifdef SQLITE_USER_AUTHENTICATION
+/*
+** Information held in the "sqlite3" database connection object and used
+** to manage user authentication.
+*/
+typedef struct sqlite3_userauth sqlite3_userauth;
+struct sqlite3_userauth {
+ u8 authLevel; /* Current authentication level */
+ int nAuthPW; /* Size of the zAuthPW in bytes */
+ char *zAuthPW; /* Password used to authenticate */
+ char *zAuthUser; /* User name used to authenticate */
+};
+
+/* Allowed values for sqlite3_userauth.authLevel */
+#define UAUTH_Unknown 0 /* Authentication not yet checked */
+#define UAUTH_Fail 1 /* User authentication failed */
+#define UAUTH_User 2 /* Authenticated as a normal user */
+#define UAUTH_Admin 3 /* Authenticated as an administrator */
+
+/* Functions used only by user authorization logic */
+SQLITE_PRIVATE int sqlite3UserAuthTable(const char*);
+SQLITE_PRIVATE int sqlite3UserAuthCheckLogin(sqlite3*,const char*,u8*);
+SQLITE_PRIVATE void sqlite3UserAuthInit(sqlite3*);
+SQLITE_PRIVATE void sqlite3CryptFunc(sqlite3_context*,int,sqlite3_value**);
+
+#endif /* SQLITE_USER_AUTHENTICATION */
+
+/*
+** typedef for the authorization callback function.
+*/
+#ifdef SQLITE_USER_AUTHENTICATION
+ typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
+ const char*, const char*);
+#else
+ typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
+ const char*);
+#endif
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/* This is an extra SQLITE_TRACE macro that indicates "legacy" tracing
+** in the style of sqlite3_trace()
+*/
+#define SQLITE_TRACE_LEGACY 0x80
+#else
+#define SQLITE_TRACE_LEGACY 0
+#endif /* SQLITE_OMIT_DEPRECATED */
+
+
+/*
+** Each database connection is an instance of the following structure.
+*/
+struct sqlite3 {
+ sqlite3_vfs *pVfs; /* OS Interface */
+ struct Vdbe *pVdbe; /* List of active virtual machines */
+ CollSeq *pDfltColl; /* The default collating sequence (BINARY) */
+ sqlite3_mutex *mutex; /* Connection mutex */
+ Db *aDb; /* All backends */
+ int nDb; /* Number of backends currently in use */
+ u32 mDbFlags; /* flags recording internal state */
+ u32 flags; /* flags settable by pragmas. See below */
+ i64 lastRowid; /* ROWID of most recent insert (see above) */
+ i64 szMmap; /* Default mmap_size setting */
+ u32 nSchemaLock; /* Do not reset the schema when non-zero */
+ unsigned int openFlags; /* Flags passed to sqlite3_vfs.xOpen() */
+ int errCode; /* Most recent error code (SQLITE_*) */
+ int errMask; /* & result codes with this before returning */
+ int iSysErrno; /* Errno value from last system error */
+ u16 dbOptFlags; /* Flags to enable/disable optimizations */
+ u8 enc; /* Text encoding */
+ u8 autoCommit; /* The auto-commit flag. */
+ u8 temp_store; /* 1: file 2: memory 0: default */
+ u8 mallocFailed; /* True if we have seen a malloc failure */
+ u8 bBenignMalloc; /* Do not require OOMs if true */
+ u8 dfltLockMode; /* Default locking-mode for attached dbs */
+ signed char nextAutovac; /* Autovac setting after VACUUM if >=0 */
+ u8 suppressErr; /* Do not issue error messages if true */
+ u8 vtabOnConflict; /* Value to return for s3_vtab_on_conflict() */
+ u8 isTransactionSavepoint; /* True if the outermost savepoint is a TS */
+ u8 mTrace; /* zero or more SQLITE_TRACE flags */
+ u8 noSharedCache; /* True if no shared-cache backends */
+ u8 nSqlExec; /* Number of pending OP_SqlExec opcodes */
+ int nextPagesize; /* Pagesize after VACUUM if >0 */
+ u32 magic; /* Magic number for detect library misuse */
+ int nChange; /* Value returned by sqlite3_changes() */
+ int nTotalChange; /* Value returned by sqlite3_total_changes() */
+ int aLimit[SQLITE_N_LIMIT]; /* Limits */
+ int nMaxSorterMmap; /* Maximum size of regions mapped by sorter */
+ struct sqlite3InitInfo { /* Information used during initialization */
+ int newTnum; /* Rootpage of table being initialized */
+ u8 iDb; /* Which db file is being initialized */
+ u8 busy; /* TRUE if currently initializing */
+ unsigned orphanTrigger : 1; /* Last statement is orphaned TEMP trigger */
+ unsigned imposterTable : 1; /* Building an imposter table */
+ unsigned reopenMemdb : 1; /* ATTACH is really a reopen using MemDB */
+ } init;
+ int nVdbeActive; /* Number of VDBEs currently running */
+ int nVdbeRead; /* Number of active VDBEs that read or write */
+ int nVdbeWrite; /* Number of active VDBEs that read and write */
+ int nVdbeExec; /* Number of nested calls to VdbeExec() */
+ int nVDestroy; /* Number of active OP_VDestroy operations */
+ int nExtension; /* Number of loaded extensions */
+ void **aExtension; /* Array of shared library handles */
+ int (*xTrace)(u32,void*,void*,void*); /* Trace function */
+ void *pTraceArg; /* Argument to the trace function */
+ void (*xProfile)(void*,const char*,u64); /* Profiling function */
+ void *pProfileArg; /* Argument to profile function */
+ void *pCommitArg; /* Argument to xCommitCallback() */
+ int (*xCommitCallback)(void*); /* Invoked at every commit. */
+ void *pRollbackArg; /* Argument to xRollbackCallback() */
+ void (*xRollbackCallback)(void*); /* Invoked at every commit. */
+ void *pUpdateArg;
+ void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
+#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
+ void *pPreUpdateArg; /* First argument to xPreUpdateCallback */
+ void (*xPreUpdateCallback)( /* Registered using sqlite3_preupdate_hook() */
+ void*,sqlite3*,int,char const*,char const*,sqlite3_int64,sqlite3_int64
+ );
+ PreUpdate *pPreUpdate; /* Context for active pre-update callback */
+#endif /* SQLITE_ENABLE_PREUPDATE_HOOK */
+#ifndef SQLITE_OMIT_WAL
+ int (*xWalCallback)(void *, sqlite3 *, const char *, int);
+ void *pWalArg;
+#endif
+ void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
+ void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
+ void *pCollNeededArg;
+ sqlite3_value *pErr; /* Most recent error message */
+ union {
+ volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
+ double notUsed1; /* Spacer */
+ } u1;
+ Lookaside lookaside; /* Lookaside malloc configuration */
+#ifndef SQLITE_OMIT_AUTHORIZATION
+ sqlite3_xauth xAuth; /* Access authorization function */
+ void *pAuthArg; /* 1st argument to the access auth function */
+#endif
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+ int (*xProgress)(void *); /* The progress callback */
+ void *pProgressArg; /* Argument to the progress callback */
+ unsigned nProgressOps; /* Number of opcodes for progress callback */
+#endif
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+ int nVTrans; /* Allocated size of aVTrans */
+ Hash aModule; /* populated by sqlite3_create_module() */
+ VtabCtx *pVtabCtx; /* Context for active vtab connect/create */
+ VTable **aVTrans; /* Virtual tables with open transactions */
+ VTable *pDisconnect; /* Disconnect these in next sqlite3_prepare() */
+#endif
+ Hash aFunc; /* Hash table of connection functions */
+ Hash aCollSeq; /* All collating sequences */
+ BusyHandler busyHandler; /* Busy callback */
+ Db aDbStatic[2]; /* Static space for the 2 default backends */
+ Savepoint *pSavepoint; /* List of active savepoints */
+ int busyTimeout; /* Busy handler timeout, in msec */
+ int nSavepoint; /* Number of non-transaction savepoints */
+ int nStatement; /* Number of nested statement-transactions */
+ i64 nDeferredCons; /* Net deferred constraints this transaction. */
+ i64 nDeferredImmCons; /* Net deferred immediate constraints */
+ int *pnBytesFreed; /* If not NULL, increment this in DbFree() */
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+ /* The following variables are all protected by the STATIC_MASTER
+ ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
+ **
+ ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
+ ** unlock so that it can proceed.
+ **
+ ** When X.pBlockingConnection==Y, that means that something that X tried
+ ** tried to do recently failed with an SQLITE_LOCKED error due to locks
+ ** held by Y.
+ */
+ sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
+ sqlite3 *pUnlockConnection; /* Connection to watch for unlock */
+ void *pUnlockArg; /* Argument to xUnlockNotify */
+ void (*xUnlockNotify)(void **, int); /* Unlock notify callback */
+ sqlite3 *pNextBlocked; /* Next in list of all blocked connections */
+#endif
+#ifdef SQLITE_USER_AUTHENTICATION
+ sqlite3_userauth auth; /* User authentication information */
+#endif
+};
+
+/*
+** A macro to discover the encoding of a database.
+*/
+#define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
+#define ENC(db) ((db)->enc)
+
+/*
+** Possible values for the sqlite3.flags.
+**
+** Value constraints (enforced via assert()):
+** SQLITE_FullFSync == PAGER_FULLFSYNC
+** SQLITE_CkptFullFSync == PAGER_CKPT_FULLFSYNC
+** SQLITE_CacheSpill == PAGER_CACHE_SPILL
+*/
+#define SQLITE_WriteSchema 0x00000001 /* OK to update SQLITE_MASTER */
+#define SQLITE_LegacyFileFmt 0x00000002 /* Create new databases in format 1 */
+#define SQLITE_FullColNames 0x00000004 /* Show full column names on SELECT */
+#define SQLITE_FullFSync 0x00000008 /* Use full fsync on the backend */
+#define SQLITE_CkptFullFSync 0x00000010 /* Use full fsync for checkpoint */
+#define SQLITE_CacheSpill 0x00000020 /* OK to spill pager cache */
+#define SQLITE_ShortColNames 0x00000040 /* Show short columns names */
+#define SQLITE_CountRows 0x00000080 /* Count rows changed by INSERT, */
+ /* DELETE, or UPDATE and return */
+ /* the count using a callback. */
+#define SQLITE_NullCallback 0x00000100 /* Invoke the callback once if the */
+ /* result set is empty */
+#define SQLITE_IgnoreChecks 0x00000200 /* Do not enforce check constraints */
+#define SQLITE_ReadUncommit 0x00000400 /* READ UNCOMMITTED in shared-cache */
+#define SQLITE_NoCkptOnClose 0x00000800 /* No checkpoint on close()/DETACH */
+#define SQLITE_ReverseOrder 0x00001000 /* Reverse unordered SELECTs */
+#define SQLITE_RecTriggers 0x00002000 /* Enable recursive triggers */
+#define SQLITE_ForeignKeys 0x00004000 /* Enforce foreign key constraints */
+#define SQLITE_AutoIndex 0x00008000 /* Enable automatic indexes */
+#define SQLITE_LoadExtension 0x00010000 /* Enable load_extension */
+#define SQLITE_LoadExtFunc 0x00020000 /* Enable load_extension() SQL func */
+#define SQLITE_EnableTrigger 0x00040000 /* True to enable triggers */
+#define SQLITE_DeferFKs 0x00080000 /* Defer all FK constraints */
+#define SQLITE_QueryOnly 0x00100000 /* Disable database changes */
+#define SQLITE_CellSizeCk 0x00200000 /* Check btree cell sizes on load */
+#define SQLITE_Fts3Tokenizer 0x00400000 /* Enable fts3_tokenizer(2) */
+#define SQLITE_EnableQPSG 0x00800000 /* Query Planner Stability Guarantee*/
+#define SQLITE_TriggerEQP 0x01000000 /* Show trigger EXPLAIN QUERY PLAN */
+#define SQLITE_ResetDatabase 0x02000000 /* Reset the database */
+#define SQLITE_LegacyAlter 0x04000000 /* Legacy ALTER TABLE behaviour */
+
+/* Flags used only if debugging */
+#ifdef SQLITE_DEBUG
+#define SQLITE_SqlTrace 0x08000000 /* Debug print SQL as it executes */
+#define SQLITE_VdbeListing 0x10000000 /* Debug listings of VDBE programs */
+#define SQLITE_VdbeTrace 0x20000000 /* True to trace VDBE execution */
+#define SQLITE_VdbeAddopTrace 0x40000000 /* Trace sqlite3VdbeAddOp() calls */
+#define SQLITE_VdbeEQP 0x80000000 /* Debug EXPLAIN QUERY PLAN */
+#endif
+
+/*
+** Allowed values for sqlite3.mDbFlags
+*/
+#define DBFLAG_SchemaChange 0x0001 /* Uncommitted Hash table changes */
+#define DBFLAG_PreferBuiltin 0x0002 /* Preference to built-in funcs */
+#define DBFLAG_Vacuum 0x0004 /* Currently in a VACUUM */
+#define DBFLAG_SchemaKnownOk 0x0008 /* Schema is known to be valid */
+
+/*
+** Bits of the sqlite3.dbOptFlags field that are used by the
+** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
+** selectively disable various optimizations.
+*/
+#define SQLITE_QueryFlattener 0x0001 /* Query flattening */
+ /* 0x0002 available for reuse */
+#define SQLITE_GroupByOrder 0x0004 /* GROUPBY cover of ORDERBY */
+#define SQLITE_FactorOutConst 0x0008 /* Constant factoring */
+#define SQLITE_DistinctOpt 0x0010 /* DISTINCT using indexes */
+#define SQLITE_CoverIdxScan 0x0020 /* Covering index scans */
+#define SQLITE_OrderByIdxJoin 0x0040 /* ORDER BY of joins via index */
+#define SQLITE_Transitive 0x0080 /* Transitive constraints */
+#define SQLITE_OmitNoopJoin 0x0100 /* Omit unused tables in joins */
+#define SQLITE_CountOfView 0x0200 /* The count-of-view optimization */
+#define SQLITE_CursorHints 0x0400 /* Add OP_CursorHint opcodes */
+#define SQLITE_Stat34 0x0800 /* Use STAT3 or STAT4 data */
+ /* TH3 expects the Stat34 ^^^^^^ value to be 0x0800. Don't change it */
+#define SQLITE_PushDown 0x1000 /* The push-down optimization */
+#define SQLITE_SimplifyJoin 0x2000 /* Convert LEFT JOIN to JOIN */
+#define SQLITE_SkipScan 0x4000 /* Skip-scans */
+#define SQLITE_PropagateConst 0x8000 /* The constant propagation opt */
+#define SQLITE_AllOpts 0xffff /* All optimizations */
+
+/*
+** Macros for testing whether or not optimizations are enabled or disabled.
+*/
+#define OptimizationDisabled(db, mask) (((db)->dbOptFlags&(mask))!=0)
+#define OptimizationEnabled(db, mask) (((db)->dbOptFlags&(mask))==0)
+
+/*
+** Return true if it OK to factor constant expressions into the initialization
+** code. The argument is a Parse object for the code generator.
+*/
+#define ConstFactorOk(P) ((P)->okConstFactor)
+
+/*
+** Possible values for the sqlite.magic field.
+** The numbers are obtained at random and have no special meaning, other
+** than being distinct from one another.
+*/
+#define SQLITE_MAGIC_OPEN 0xa029a697 /* Database is open */
+#define SQLITE_MAGIC_CLOSED 0x9f3c2d33 /* Database is closed */
+#define SQLITE_MAGIC_SICK 0x4b771290 /* Error and awaiting close */
+#define SQLITE_MAGIC_BUSY 0xf03b7906 /* Database currently in use */
+#define SQLITE_MAGIC_ERROR 0xb5357930 /* An SQLITE_MISUSE error occurred */
+#define SQLITE_MAGIC_ZOMBIE 0x64cffc7f /* Close with last statement close */
+
+/*
+** Each SQL function is defined by an instance of the following
+** structure. For global built-in functions (ex: substr(), max(), count())
+** a pointer to this structure is held in the sqlite3BuiltinFunctions object.
+** For per-connection application-defined functions, a pointer to this
+** structure is held in the db->aHash hash table.
+**
+** The u.pHash field is used by the global built-ins. The u.pDestructor
+** field is used by per-connection app-def functions.
+*/
+struct FuncDef {
+ i8 nArg; /* Number of arguments. -1 means unlimited */
+ u32 funcFlags; /* Some combination of SQLITE_FUNC_* */
+ void *pUserData; /* User data parameter */
+ FuncDef *pNext; /* Next function with same name */
+ void (*xSFunc)(sqlite3_context*,int,sqlite3_value**); /* func or agg-step */
+ void (*xFinalize)(sqlite3_context*); /* Agg finalizer */
+ void (*xValue)(sqlite3_context*); /* Current agg value */
+ void (*xInverse)(sqlite3_context*,int,sqlite3_value**); /* inverse agg-step */
+ const char *zName; /* SQL name of the function. */
+ union {
+ FuncDef *pHash; /* Next with a different name but the same hash */
+ FuncDestructor *pDestructor; /* Reference counted destructor function */
+ } u;
+};
+
+/*
+** This structure encapsulates a user-function destructor callback (as
+** configured using create_function_v2()) and a reference counter. When
+** create_function_v2() is called to create a function with a destructor,
+** a single object of this type is allocated. FuncDestructor.nRef is set to
+** the number of FuncDef objects created (either 1 or 3, depending on whether
+** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
+** member of each of the new FuncDef objects is set to point to the allocated
+** FuncDestructor.
+**
+** Thereafter, when one of the FuncDef objects is deleted, the reference
+** count on this object is decremented. When it reaches 0, the destructor
+** is invoked and the FuncDestructor structure freed.
+*/
+struct FuncDestructor {
+ int nRef;
+ void (*xDestroy)(void *);
+ void *pUserData;
+};
+
+/*
+** Possible values for FuncDef.flags. Note that the _LENGTH and _TYPEOF
+** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG. And
+** SQLITE_FUNC_CONSTANT must be the same as SQLITE_DETERMINISTIC. There
+** are assert() statements in the code to verify this.
+**
+** Value constraints (enforced via assert()):
+** SQLITE_FUNC_MINMAX == NC_MinMaxAgg == SF_MinMaxAgg
+** SQLITE_FUNC_LENGTH == OPFLAG_LENGTHARG
+** SQLITE_FUNC_TYPEOF == OPFLAG_TYPEOFARG
+** SQLITE_FUNC_CONSTANT == SQLITE_DETERMINISTIC from the API
+** SQLITE_FUNC_ENCMASK depends on SQLITE_UTF* macros in the API
+*/
+#define SQLITE_FUNC_ENCMASK 0x0003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
+#define SQLITE_FUNC_LIKE 0x0004 /* Candidate for the LIKE optimization */
+#define SQLITE_FUNC_CASE 0x0008 /* Case-sensitive LIKE-type function */
+#define SQLITE_FUNC_EPHEM 0x0010 /* Ephemeral. Delete with VDBE */
+#define SQLITE_FUNC_NEEDCOLL 0x0020 /* sqlite3GetFuncCollSeq() might be called*/
+#define SQLITE_FUNC_LENGTH 0x0040 /* Built-in length() function */
+#define SQLITE_FUNC_TYPEOF 0x0080 /* Built-in typeof() function */
+#define SQLITE_FUNC_COUNT 0x0100 /* Built-in count(*) aggregate */
+#define SQLITE_FUNC_COALESCE 0x0200 /* Built-in coalesce() or ifnull() */
+#define SQLITE_FUNC_UNLIKELY 0x0400 /* Built-in unlikely() function */
+#define SQLITE_FUNC_CONSTANT 0x0800 /* Constant inputs give a constant output */
+#define SQLITE_FUNC_MINMAX 0x1000 /* True for min() and max() aggregates */
+#define SQLITE_FUNC_SLOCHNG 0x2000 /* "Slow Change". Value constant during a
+ ** single query - might change over time */
+#define SQLITE_FUNC_AFFINITY 0x4000 /* Built-in affinity() function */
+#define SQLITE_FUNC_OFFSET 0x8000 /* Built-in sqlite_offset() function */
+#define SQLITE_FUNC_WINDOW 0x10000 /* Built-in window-only function */
+#define SQLITE_FUNC_WINDOW_SIZE 0x20000 /* Requires partition size as arg. */
+
+/*
+** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
+** used to create the initializers for the FuncDef structures.
+**
+** FUNCTION(zName, nArg, iArg, bNC, xFunc)
+** Used to create a scalar function definition of a function zName
+** implemented by C function xFunc that accepts nArg arguments. The
+** value passed as iArg is cast to a (void*) and made available
+** as the user-data (sqlite3_user_data()) for the function. If
+** argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
+**
+** VFUNCTION(zName, nArg, iArg, bNC, xFunc)
+** Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
+**
+** DFUNCTION(zName, nArg, iArg, bNC, xFunc)
+** Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
+** adds the SQLITE_FUNC_SLOCHNG flag. Used for date & time functions
+** and functions like sqlite_version() that can change, but not during
+** a single query. The iArg is ignored. The user-data is always set
+** to a NULL pointer. The bNC parameter is not used.
+**
+** PURE_DATE(zName, nArg, iArg, bNC, xFunc)
+** Used for "pure" date/time functions, this macro is like DFUNCTION
+** except that it does set the SQLITE_FUNC_CONSTANT flags. iArg is
+** ignored and the user-data for these functions is set to an
+** arbitrary non-NULL pointer. The bNC parameter is not used.
+**
+** AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
+** Used to create an aggregate function definition implemented by
+** the C functions xStep and xFinal. The first four parameters
+** are interpreted in the same way as the first 4 parameters to
+** FUNCTION().
+**
+** WFUNCTION(zName, nArg, iArg, xStep, xFinal, xValue, xInverse)
+** Used to create an aggregate function definition implemented by
+** the C functions xStep and xFinal. The first four parameters
+** are interpreted in the same way as the first 4 parameters to
+** FUNCTION().
+**
+** LIKEFUNC(zName, nArg, pArg, flags)
+** Used to create a scalar function definition of a function zName
+** that accepts nArg arguments and is implemented by a call to C
+** function likeFunc. Argument pArg is cast to a (void *) and made
+** available as the function user-data (sqlite3_user_data()). The
+** FuncDef.flags variable is set to the value passed as the flags
+** parameter.
+*/
+#define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
+ {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
+ SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
+#define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
+ {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
+ SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
+#define DFUNCTION(zName, nArg, iArg, bNC, xFunc) \
+ {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8, \
+ 0, 0, xFunc, 0, 0, 0, #zName, {0} }
+#define PURE_DATE(zName, nArg, iArg, bNC, xFunc) \
+ {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|SQLITE_FUNC_CONSTANT, \
+ (void*)&sqlite3Config, 0, xFunc, 0, 0, 0, #zName, {0} }
+#define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
+ {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
+ SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
+#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
+ {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
+ pArg, 0, xFunc, 0, 0, 0, #zName, }
+#define LIKEFUNC(zName, nArg, arg, flags) \
+ {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
+ (void *)arg, 0, likeFunc, 0, 0, 0, #zName, {0} }
+#define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal, xValue) \
+ {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
+ SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,xValue,0,#zName, {0}}
+#define AGGREGATE2(zName, nArg, arg, nc, xStep, xFinal, extraFlags) \
+ {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|extraFlags, \
+ SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,xFinal,0,#zName, {0}}
+
+#define WAGGREGATE(zName, nArg, arg, nc, xStep, xFinal, xValue, xInverse, f) \
+ {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|f, \
+ SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,xValue,xInverse,#zName, {0}}
+
+/*
+** All current savepoints are stored in a linked list starting at
+** sqlite3.pSavepoint. The first element in the list is the most recently
+** opened savepoint. Savepoints are added to the list by the vdbe
+** OP_Savepoint instruction.
+*/
+struct Savepoint {
+ char *zName; /* Savepoint name (nul-terminated) */
+ i64 nDeferredCons; /* Number of deferred fk violations */
+ i64 nDeferredImmCons; /* Number of deferred imm fk. */
+ Savepoint *pNext; /* Parent savepoint (if any) */
+};
+
+/*
+** The following are used as the second parameter to sqlite3Savepoint(),
+** and as the P1 argument to the OP_Savepoint instruction.
+*/
+#define SAVEPOINT_BEGIN 0
+#define SAVEPOINT_RELEASE 1
+#define SAVEPOINT_ROLLBACK 2
+
+
+/*
+** Each SQLite module (virtual table definition) is defined by an
+** instance of the following structure, stored in the sqlite3.aModule
+** hash table.
+*/
+struct Module {
+ const sqlite3_module *pModule; /* Callback pointers */
+ const char *zName; /* Name passed to create_module() */
+ void *pAux; /* pAux passed to create_module() */
+ void (*xDestroy)(void *); /* Module destructor function */
+ Table *pEpoTab; /* Eponymous table for this module */
+};
+
+/*
+** information about each column of an SQL table is held in an instance
+** of this structure.
+*/
+struct Column {
+ char *zName; /* Name of this column, \000, then the type */
+ Expr *pDflt; /* Default value of this column */
+ char *zColl; /* Collating sequence. If NULL, use the default */
+ u8 notNull; /* An OE_ code for handling a NOT NULL constraint */
+ char affinity; /* One of the SQLITE_AFF_... values */
+ u8 szEst; /* Estimated size of value in this column. sizeof(INT)==1 */
+ u8 colFlags; /* Boolean properties. See COLFLAG_ defines below */
+};
+
+/* Allowed values for Column.colFlags:
+*/
+#define COLFLAG_PRIMKEY 0x0001 /* Column is part of the primary key */
+#define COLFLAG_HIDDEN 0x0002 /* A hidden column in a virtual table */
+#define COLFLAG_HASTYPE 0x0004 /* Type name follows column name */
+#define COLFLAG_UNIQUE 0x0008 /* Column def contains "UNIQUE" or "PK" */
+#define COLFLAG_SORTERREF 0x0010 /* Use sorter-refs with this column */
+
+/*
+** A "Collating Sequence" is defined by an instance of the following
+** structure. Conceptually, a collating sequence consists of a name and
+** a comparison routine that defines the order of that sequence.
+**
+** If CollSeq.xCmp is NULL, it means that the
+** collating sequence is undefined. Indices built on an undefined
+** collating sequence may not be read or written.
+*/
+struct CollSeq {
+ char *zName; /* Name of the collating sequence, UTF-8 encoded */
+ u8 enc; /* Text encoding handled by xCmp() */
+ void *pUser; /* First argument to xCmp() */
+ int (*xCmp)(void*,int, const void*, int, const void*);
+ void (*xDel)(void*); /* Destructor for pUser */
+};
+
+/*
+** A sort order can be either ASC or DESC.
+*/
+#define SQLITE_SO_ASC 0 /* Sort in ascending order */
+#define SQLITE_SO_DESC 1 /* Sort in ascending order */
+#define SQLITE_SO_UNDEFINED -1 /* No sort order specified */
+
+/*
+** Column affinity types.
+**
+** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
+** 't' for SQLITE_AFF_TEXT. But we can save a little space and improve
+** the speed a little by numbering the values consecutively.
+**
+** But rather than start with 0 or 1, we begin with 'A'. That way,
+** when multiple affinity types are concatenated into a string and
+** used as the P4 operand, they will be more readable.
+**
+** Note also that the numeric types are grouped together so that testing
+** for a numeric type is a single comparison. And the BLOB type is first.
+*/
+#define SQLITE_AFF_BLOB 'A'
+#define SQLITE_AFF_TEXT 'B'
+#define SQLITE_AFF_NUMERIC 'C'
+#define SQLITE_AFF_INTEGER 'D'
+#define SQLITE_AFF_REAL 'E'
+
+#define sqlite3IsNumericAffinity(X) ((X)>=SQLITE_AFF_NUMERIC)
+
+/*
+** The SQLITE_AFF_MASK values masks off the significant bits of an
+** affinity value.
+*/
+#define SQLITE_AFF_MASK 0x47
+
+/*
+** Additional bit values that can be ORed with an affinity without
+** changing the affinity.
+**
+** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
+** It causes an assert() to fire if either operand to a comparison
+** operator is NULL. It is added to certain comparison operators to
+** prove that the operands are always NOT NULL.
+*/
+#define SQLITE_KEEPNULL 0x08 /* Used by vector == or <> */
+#define SQLITE_JUMPIFNULL 0x10 /* jumps if either operand is NULL */
+#define SQLITE_STOREP2 0x20 /* Store result in reg[P2] rather than jump */
+#define SQLITE_NULLEQ 0x80 /* NULL=NULL */
+#define SQLITE_NOTNULL 0x90 /* Assert that operands are never NULL */
+
+/*
+** An object of this type is created for each virtual table present in
+** the database schema.
+**
+** If the database schema is shared, then there is one instance of this
+** structure for each database connection (sqlite3*) that uses the shared
+** schema. This is because each database connection requires its own unique
+** instance of the sqlite3_vtab* handle used to access the virtual table
+** implementation. sqlite3_vtab* handles can not be shared between
+** database connections, even when the rest of the in-memory database
+** schema is shared, as the implementation often stores the database
+** connection handle passed to it via the xConnect() or xCreate() method
+** during initialization internally. This database connection handle may
+** then be used by the virtual table implementation to access real tables
+** within the database. So that they appear as part of the callers
+** transaction, these accesses need to be made via the same database
+** connection as that used to execute SQL operations on the virtual table.
+**
+** All VTable objects that correspond to a single table in a shared
+** database schema are initially stored in a linked-list pointed to by
+** the Table.pVTable member variable of the corresponding Table object.
+** When an sqlite3_prepare() operation is required to access the virtual
+** table, it searches the list for the VTable that corresponds to the
+** database connection doing the preparing so as to use the correct
+** sqlite3_vtab* handle in the compiled query.
+**
+** When an in-memory Table object is deleted (for example when the
+** schema is being reloaded for some reason), the VTable objects are not
+** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
+** immediately. Instead, they are moved from the Table.pVTable list to
+** another linked list headed by the sqlite3.pDisconnect member of the
+** corresponding sqlite3 structure. They are then deleted/xDisconnected
+** next time a statement is prepared using said sqlite3*. This is done
+** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
+** Refer to comments above function sqlite3VtabUnlockList() for an
+** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
+** list without holding the corresponding sqlite3.mutex mutex.
+**
+** The memory for objects of this type is always allocated by
+** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
+** the first argument.
+*/
+struct VTable {
+ sqlite3 *db; /* Database connection associated with this table */
+ Module *pMod; /* Pointer to module implementation */
+ sqlite3_vtab *pVtab; /* Pointer to vtab instance */
+ int nRef; /* Number of pointers to this structure */
+ u8 bConstraint; /* True if constraints are supported */
+ int iSavepoint; /* Depth of the SAVEPOINT stack */
+ VTable *pNext; /* Next in linked list (see above) */
+};
+
+/*
+** The schema for each SQL table and view is represented in memory
+** by an instance of the following structure.
+*/
+struct Table {
+ char *zName; /* Name of the table or view */
+ Column *aCol; /* Information about each column */
+ Index *pIndex; /* List of SQL indexes on this table. */
+ Select *pSelect; /* NULL for tables. Points to definition if a view. */
+ FKey *pFKey; /* Linked list of all foreign keys in this table */
+ char *zColAff; /* String defining the affinity of each column */
+ ExprList *pCheck; /* All CHECK constraints */
+ /* ... also used as column name list in a VIEW */
+ int tnum; /* Root BTree page for this table */
+ u32 nTabRef; /* Number of pointers to this Table */
+ u32 tabFlags; /* Mask of TF_* values */
+ i16 iPKey; /* If not negative, use aCol[iPKey] as the rowid */
+ i16 nCol; /* Number of columns in this table */
+ LogEst nRowLogEst; /* Estimated rows in table - from sqlite_stat1 table */
+ LogEst szTabRow; /* Estimated size of each table row in bytes */
+#ifdef SQLITE_ENABLE_COSTMULT
+ LogEst costMult; /* Cost multiplier for using this table */
+#endif
+ u8 keyConf; /* What to do in case of uniqueness conflict on iPKey */
+#ifndef SQLITE_OMIT_ALTERTABLE
+ int addColOffset; /* Offset in CREATE TABLE stmt to add a new column */
+#endif
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+ int nModuleArg; /* Number of arguments to the module */
+ char **azModuleArg; /* 0: module 1: schema 2: vtab name 3...: args */
+ VTable *pVTable; /* List of VTable objects. */
+#endif
+ Trigger *pTrigger; /* List of triggers stored in pSchema */
+ Schema *pSchema; /* Schema that contains this table */
+ Table *pNextZombie; /* Next on the Parse.pZombieTab list */
+};
+
+/*
+** Allowed values for Table.tabFlags.
+**
+** TF_OOOHidden applies to tables or view that have hidden columns that are
+** followed by non-hidden columns. Example: "CREATE VIRTUAL TABLE x USING
+** vtab1(a HIDDEN, b);". Since "b" is a non-hidden column but "a" is hidden,
+** the TF_OOOHidden attribute would apply in this case. Such tables require
+** special handling during INSERT processing.
+*/
+#define TF_Readonly 0x0001 /* Read-only system table */
+#define TF_Ephemeral 0x0002 /* An ephemeral table */
+#define TF_HasPrimaryKey 0x0004 /* Table has a primary key */
+#define TF_Autoincrement 0x0008 /* Integer primary key is autoincrement */
+#define TF_HasStat1 0x0010 /* nRowLogEst set from sqlite_stat1 */
+#define TF_WithoutRowid 0x0020 /* No rowid. PRIMARY KEY is the key */
+#define TF_NoVisibleRowid 0x0040 /* No user-visible "rowid" column */
+#define TF_OOOHidden 0x0080 /* Out-of-Order hidden columns */
+#define TF_StatsUsed 0x0100 /* Query planner decisions affected by
+ ** Index.aiRowLogEst[] values */
+#define TF_HasNotNull 0x0200 /* Contains NOT NULL constraints */
+
+/*
+** Test to see whether or not a table is a virtual table. This is
+** done as a macro so that it will be optimized out when virtual
+** table support is omitted from the build.
+*/
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+# define IsVirtual(X) ((X)->nModuleArg)
+#else
+# define IsVirtual(X) 0
+#endif
+
+/*
+** Macros to determine if a column is hidden. IsOrdinaryHiddenColumn()
+** only works for non-virtual tables (ordinary tables and views) and is
+** always false unless SQLITE_ENABLE_HIDDEN_COLUMNS is defined. The
+** IsHiddenColumn() macro is general purpose.
+*/
+#if defined(SQLITE_ENABLE_HIDDEN_COLUMNS)
+# define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
+# define IsOrdinaryHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
+#elif !defined(SQLITE_OMIT_VIRTUALTABLE)
+# define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
+# define IsOrdinaryHiddenColumn(X) 0
+#else
+# define IsHiddenColumn(X) 0
+# define IsOrdinaryHiddenColumn(X) 0
+#endif
+
+
+/* Does the table have a rowid */
+#define HasRowid(X) (((X)->tabFlags & TF_WithoutRowid)==0)
+#define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)
+
+/*
+** Each foreign key constraint is an instance of the following structure.
+**
+** A foreign key is associated with two tables. The "from" table is
+** the table that contains the REFERENCES clause that creates the foreign
+** key. The "to" table is the table that is named in the REFERENCES clause.
+** Consider this example:
+**
+** CREATE TABLE ex1(
+** a INTEGER PRIMARY KEY,
+** b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
+** );
+**
+** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
+** Equivalent names:
+**
+** from-table == child-table
+** to-table == parent-table
+**
+** Each REFERENCES clause generates an instance of the following structure
+** which is attached to the from-table. The to-table need not exist when
+** the from-table is created. The existence of the to-table is not checked.
+**
+** The list of all parents for child Table X is held at X.pFKey.
+**
+** A list of all children for a table named Z (which might not even exist)
+** is held in Schema.fkeyHash with a hash key of Z.
+*/
+struct FKey {
+ Table *pFrom; /* Table containing the REFERENCES clause (aka: Child) */
+ FKey *pNextFrom; /* Next FKey with the same in pFrom. Next parent of pFrom */
+ char *zTo; /* Name of table that the key points to (aka: Parent) */
+ FKey *pNextTo; /* Next with the same zTo. Next child of zTo. */
+ FKey *pPrevTo; /* Previous with the same zTo */
+ int nCol; /* Number of columns in this key */
+ /* EV: R-30323-21917 */
+ u8 isDeferred; /* True if constraint checking is deferred till COMMIT */
+ u8 aAction[2]; /* ON DELETE and ON UPDATE actions, respectively */
+ Trigger *apTrigger[2];/* Triggers for aAction[] actions */
+ struct sColMap { /* Mapping of columns in pFrom to columns in zTo */
+ int iFrom; /* Index of column in pFrom */
+ char *zCol; /* Name of column in zTo. If NULL use PRIMARY KEY */
+ } aCol[1]; /* One entry for each of nCol columns */
+};
+
+/*
+** SQLite supports many different ways to resolve a constraint
+** error. ROLLBACK processing means that a constraint violation
+** causes the operation in process to fail and for the current transaction
+** to be rolled back. ABORT processing means the operation in process
+** fails and any prior changes from that one operation are backed out,
+** but the transaction is not rolled back. FAIL processing means that
+** the operation in progress stops and returns an error code. But prior
+** changes due to the same operation are not backed out and no rollback
+** occurs. IGNORE means that the particular row that caused the constraint
+** error is not inserted or updated. Processing continues and no error
+** is returned. REPLACE means that preexisting database rows that caused
+** a UNIQUE constraint violation are removed so that the new insert or
+** update can proceed. Processing continues and no error is reported.
+**
+** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
+** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
+** same as ROLLBACK for DEFERRED keys. SETNULL means that the foreign
+** key is set to NULL. CASCADE means that a DELETE or UPDATE of the
+** referenced table row is propagated into the row that holds the
+** foreign key.
+**
+** The following symbolic values are used to record which type
+** of action to take.
+*/
+#define OE_None 0 /* There is no constraint to check */
+#define OE_Rollback 1 /* Fail the operation and rollback the transaction */
+#define OE_Abort 2 /* Back out changes but do no rollback transaction */
+#define OE_Fail 3 /* Stop the operation but leave all prior changes */
+#define OE_Ignore 4 /* Ignore the error. Do not do the INSERT or UPDATE */
+#define OE_Replace 5 /* Delete existing record, then do INSERT or UPDATE */
+#define OE_Update 6 /* Process as a DO UPDATE in an upsert */
+#define OE_Restrict 7 /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
+#define OE_SetNull 8 /* Set the foreign key value to NULL */
+#define OE_SetDflt 9 /* Set the foreign key value to its default */
+#define OE_Cascade 10 /* Cascade the changes */
+#define OE_Default 11 /* Do whatever the default action is */
+
+
+/*
+** An instance of the following structure is passed as the first
+** argument to sqlite3VdbeKeyCompare and is used to control the
+** comparison of the two index keys.
+**
+** Note that aSortOrder[] and aColl[] have nField+1 slots. There
+** are nField slots for the columns of an index then one extra slot
+** for the rowid at the end.
+*/
+struct KeyInfo {
+ u32 nRef; /* Number of references to this KeyInfo object */
+ u8 enc; /* Text encoding - one of the SQLITE_UTF* values */
+ u16 nKeyField; /* Number of key columns in the index */
+ u16 nAllField; /* Total columns, including key plus others */
+ sqlite3 *db; /* The database connection */
+ u8 *aSortOrder; /* Sort order for each column. */
+ CollSeq *aColl[1]; /* Collating sequence for each term of the key */
+};
+
+/*
+** This object holds a record which has been parsed out into individual
+** fields, for the purposes of doing a comparison.
+**
+** A record is an object that contains one or more fields of data.
+** Records are used to store the content of a table row and to store
+** the key of an index. A blob encoding of a record is created by
+** the OP_MakeRecord opcode of the VDBE and is disassembled by the
+** OP_Column opcode.
+**
+** An instance of this object serves as a "key" for doing a search on
+** an index b+tree. The goal of the search is to find the entry that
+** is closed to the key described by this object. This object might hold
+** just a prefix of the key. The number of fields is given by
+** pKeyInfo->nField.
+**
+** The r1 and r2 fields are the values to return if this key is less than
+** or greater than a key in the btree, respectively. These are normally
+** -1 and +1 respectively, but might be inverted to +1 and -1 if the b-tree
+** is in DESC order.
+**
+** The key comparison functions actually return default_rc when they find
+** an equals comparison. default_rc can be -1, 0, or +1. If there are
+** multiple entries in the b-tree with the same key (when only looking
+** at the first pKeyInfo->nFields,) then default_rc can be set to -1 to
+** cause the search to find the last match, or +1 to cause the search to
+** find the first match.
+**
+** The key comparison functions will set eqSeen to true if they ever
+** get and equal results when comparing this structure to a b-tree record.
+** When default_rc!=0, the search might end up on the record immediately
+** before the first match or immediately after the last match. The
+** eqSeen field will indicate whether or not an exact match exists in the
+** b-tree.
+*/
+struct UnpackedRecord {
+ KeyInfo *pKeyInfo; /* Collation and sort-order information */
+ Mem *aMem; /* Values */
+ u16 nField; /* Number of entries in apMem[] */
+ i8 default_rc; /* Comparison result if keys are equal */
+ u8 errCode; /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
+ i8 r1; /* Value to return if (lhs < rhs) */
+ i8 r2; /* Value to return if (lhs > rhs) */
+ u8 eqSeen; /* True if an equality comparison has been seen */
+};
+
+
+/*
+** Each SQL index is represented in memory by an
+** instance of the following structure.
+**
+** The columns of the table that are to be indexed are described
+** by the aiColumn[] field of this structure. For example, suppose
+** we have the following table and index:
+**
+** CREATE TABLE Ex1(c1 int, c2 int, c3 text);
+** CREATE INDEX Ex2 ON Ex1(c3,c1);
+**
+** In the Table structure describing Ex1, nCol==3 because there are
+** three columns in the table. In the Index structure describing
+** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
+** The value of aiColumn is {2, 0}. aiColumn[0]==2 because the
+** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
+** The second column to be indexed (c1) has an index of 0 in
+** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
+**
+** The Index.onError field determines whether or not the indexed columns
+** must be unique and what to do if they are not. When Index.onError=OE_None,
+** it means this is not a unique index. Otherwise it is a unique index
+** and the value of Index.onError indicate the which conflict resolution
+** algorithm to employ whenever an attempt is made to insert a non-unique
+** element.
+**
+** While parsing a CREATE TABLE or CREATE INDEX statement in order to
+** generate VDBE code (as opposed to parsing one read from an sqlite_master
+** table as part of parsing an existing database schema), transient instances
+** of this structure may be created. In this case the Index.tnum variable is
+** used to store the address of a VDBE instruction, not a database page
+** number (it cannot - the database page is not allocated until the VDBE
+** program is executed). See convertToWithoutRowidTable() for details.
+*/
+struct Index {
+ char *zName; /* Name of this index */
+ i16 *aiColumn; /* Which columns are used by this index. 1st is 0 */
+ LogEst *aiRowLogEst; /* From ANALYZE: Est. rows selected by each column */
+ Table *pTable; /* The SQL table being indexed */
+ char *zColAff; /* String defining the affinity of each column */
+ Index *pNext; /* The next index associated with the same table */
+ Schema *pSchema; /* Schema containing this index */
+ u8 *aSortOrder; /* for each column: True==DESC, False==ASC */
+ const char **azColl; /* Array of collation sequence names for index */
+ Expr *pPartIdxWhere; /* WHERE clause for partial indices */
+ ExprList *aColExpr; /* Column expressions */
+ int tnum; /* DB Page containing root of this index */
+ LogEst szIdxRow; /* Estimated average row size in bytes */
+ u16 nKeyCol; /* Number of columns forming the key */
+ u16 nColumn; /* Number of columns stored in the index */
+ u8 onError; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
+ unsigned idxType:2; /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
+ unsigned bUnordered:1; /* Use this index for == or IN queries only */
+ unsigned uniqNotNull:1; /* True if UNIQUE and NOT NULL for all columns */
+ unsigned isResized:1; /* True if resizeIndexObject() has been called */
+ unsigned isCovering:1; /* True if this is a covering index */
+ unsigned noSkipScan:1; /* Do not try to use skip-scan if true */
+ unsigned hasStat1:1; /* aiRowLogEst values come from sqlite_stat1 */
+ unsigned bNoQuery:1; /* Do not use this index to optimize queries */
+#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
+ int nSample; /* Number of elements in aSample[] */
+ int nSampleCol; /* Size of IndexSample.anEq[] and so on */
+ tRowcnt *aAvgEq; /* Average nEq values for keys not in aSample */
+ IndexSample *aSample; /* Samples of the left-most key */
+ tRowcnt *aiRowEst; /* Non-logarithmic stat1 data for this index */
+ tRowcnt nRowEst0; /* Non-logarithmic number of rows in the index */
+#endif
+ Bitmask colNotIdxed; /* 0 for unindexed columns in pTab */
+};
+
+/*
+** Allowed values for Index.idxType
+*/
+#define SQLITE_IDXTYPE_APPDEF 0 /* Created using CREATE INDEX */
+#define SQLITE_IDXTYPE_UNIQUE 1 /* Implements a UNIQUE constraint */
+#define SQLITE_IDXTYPE_PRIMARYKEY 2 /* Is the PRIMARY KEY for the table */
+
+/* Return true if index X is a PRIMARY KEY index */
+#define IsPrimaryKeyIndex(X) ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
+
+/* Return true if index X is a UNIQUE index */
+#define IsUniqueIndex(X) ((X)->onError!=OE_None)
+
+/* The Index.aiColumn[] values are normally positive integer. But
+** there are some negative values that have special meaning:
+*/
+#define XN_ROWID (-1) /* Indexed column is the rowid */
+#define XN_EXPR (-2) /* Indexed column is an expression */
+
+/*
+** Each sample stored in the sqlite_stat3 table is represented in memory
+** using a structure of this type. See documentation at the top of the
+** analyze.c source file for additional information.
+*/
+struct IndexSample {
+ void *p; /* Pointer to sampled record */
+ int n; /* Size of record in bytes */
+ tRowcnt *anEq; /* Est. number of rows where the key equals this sample */
+ tRowcnt *anLt; /* Est. number of rows where key is less than this sample */
+ tRowcnt *anDLt; /* Est. number of distinct keys less than this sample */
+};
+
+/*
+** Each token coming out of the lexer is an instance of
+** this structure. Tokens are also used as part of an expression.
+**
+** The memory that "z" points to is owned by other objects. Take care
+** that the owner of the "z" string does not deallocate the string before
+** the Token goes out of scope! Very often, the "z" points to some place
+** in the middle of the Parse.zSql text. But it might also point to a
+** static string.
+*/
+struct Token {
+ const char *z; /* Text of the token. Not NULL-terminated! */
+ unsigned int n; /* Number of characters in this token */
+};
+
+/*
+** An instance of this structure contains information needed to generate
+** code for a SELECT that contains aggregate functions.
+**
+** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
+** pointer to this structure. The Expr.iColumn field is the index in
+** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
+** code for that node.
+**
+** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
+** original Select structure that describes the SELECT statement. These
+** fields do not need to be freed when deallocating the AggInfo structure.
+*/
+struct AggInfo {
+ u8 directMode; /* Direct rendering mode means take data directly
+ ** from source tables rather than from accumulators */
+ u8 useSortingIdx; /* In direct mode, reference the sorting index rather
+ ** than the source table */
+ int sortingIdx; /* Cursor number of the sorting index */
+ int sortingIdxPTab; /* Cursor number of pseudo-table */
+ int nSortingColumn; /* Number of columns in the sorting index */
+ int mnReg, mxReg; /* Range of registers allocated for aCol and aFunc */
+ ExprList *pGroupBy; /* The group by clause */
+ struct AggInfo_col { /* For each column used in source tables */
+ Table *pTab; /* Source table */
+ int iTable; /* Cursor number of the source table */
+ int iColumn; /* Column number within the source table */
+ int iSorterColumn; /* Column number in the sorting index */
+ int iMem; /* Memory location that acts as accumulator */
+ Expr *pExpr; /* The original expression */
+ } *aCol;
+ int nColumn; /* Number of used entries in aCol[] */
+ int nAccumulator; /* Number of columns that show through to the output.
+ ** Additional columns are used only as parameters to
+ ** aggregate functions */
+ struct AggInfo_func { /* For each aggregate function */
+ Expr *pExpr; /* Expression encoding the function */
+ FuncDef *pFunc; /* The aggregate function implementation */
+ int iMem; /* Memory location that acts as accumulator */
+ int iDistinct; /* Ephemeral table used to enforce DISTINCT */
+ } *aFunc;
+ int nFunc; /* Number of entries in aFunc[] */
+};
+
+/*
+** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
+** Usually it is 16-bits. But if SQLITE_MAX_VARIABLE_NUMBER is greater
+** than 32767 we have to make it 32-bit. 16-bit is preferred because
+** it uses less memory in the Expr object, which is a big memory user
+** in systems with lots of prepared statements. And few applications
+** need more than about 10 or 20 variables. But some extreme users want
+** to have prepared statements with over 32767 variables, and for them
+** the option is available (at compile-time).
+*/
+#if SQLITE_MAX_VARIABLE_NUMBER<=32767
+typedef i16 ynVar;
+#else
+typedef int ynVar;
+#endif
+
+/*
+** Each node of an expression in the parse tree is an instance
+** of this structure.
+**
+** Expr.op is the opcode. The integer parser token codes are reused
+** as opcodes here. For example, the parser defines TK_GE to be an integer
+** code representing the ">=" operator. This same integer code is reused
+** to represent the greater-than-or-equal-to operator in the expression
+** tree.
+**
+** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
+** or TK_STRING), then Expr.token contains the text of the SQL literal. If
+** the expression is a variable (TK_VARIABLE), then Expr.token contains the
+** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
+** then Expr.token contains the name of the function.
+**
+** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
+** binary operator. Either or both may be NULL.
+**
+** Expr.x.pList is a list of arguments if the expression is an SQL function,
+** a CASE expression or an IN expression of the form " IN (, ...)".
+** Expr.x.pSelect is used if the expression is a sub-select or an expression of
+** the form " IN (SELECT ...)". If the EP_xIsSelect bit is set in the
+** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
+** valid.
+**
+** An expression of the form ID or ID.ID refers to a column in a table.
+** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
+** the integer cursor number of a VDBE cursor pointing to that table and
+** Expr.iColumn is the column number for the specific column. If the
+** expression is used as a result in an aggregate SELECT, then the
+** value is also stored in the Expr.iAgg column in the aggregate so that
+** it can be accessed after all aggregates are computed.
+**
+** If the expression is an unbound variable marker (a question mark
+** character '?' in the original SQL) then the Expr.iTable holds the index
+** number for that variable.
+**
+** If the expression is a subquery then Expr.iColumn holds an integer
+** register number containing the result of the subquery. If the
+** subquery gives a constant result, then iTable is -1. If the subquery
+** gives a different answer at different times during statement processing
+** then iTable is the address of a subroutine that computes the subquery.
+**
+** If the Expr is of type OP_Column, and the table it is selecting from
+** is a disk table or the "old.*" pseudo-table, then pTab points to the
+** corresponding table definition.
+**
+** ALLOCATION NOTES:
+**
+** Expr objects can use a lot of memory space in database schema. To
+** help reduce memory requirements, sometimes an Expr object will be
+** truncated. And to reduce the number of memory allocations, sometimes
+** two or more Expr objects will be stored in a single memory allocation,
+** together with Expr.zToken strings.
+**
+** If the EP_Reduced and EP_TokenOnly flags are set when
+** an Expr object is truncated. When EP_Reduced is set, then all
+** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
+** are contained within the same memory allocation. Note, however, that
+** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
+** allocated, regardless of whether or not EP_Reduced is set.
+*/
+struct Expr {
+ u8 op; /* Operation performed by this node */
+ char affinity; /* The affinity of the column or 0 if not a column */
+ u32 flags; /* Various flags. EP_* See below */
+ union {
+ char *zToken; /* Token value. Zero terminated and dequoted */
+ int iValue; /* Non-negative integer value if EP_IntValue */
+ } u;
+
+ /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
+ ** space is allocated for the fields below this point. An attempt to
+ ** access them will result in a segfault or malfunction.
+ *********************************************************************/
+
+ Expr *pLeft; /* Left subnode */
+ Expr *pRight; /* Right subnode */
+ union {
+ ExprList *pList; /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
+ Select *pSelect; /* EP_xIsSelect and op = IN, EXISTS, SELECT */
+ } x;
+
+ /* If the EP_Reduced flag is set in the Expr.flags mask, then no
+ ** space is allocated for the fields below this point. An attempt to
+ ** access them will result in a segfault or malfunction.
+ *********************************************************************/
+
+#if SQLITE_MAX_EXPR_DEPTH>0
+ int nHeight; /* Height of the tree headed by this node */
+#endif
+ int iTable; /* TK_COLUMN: cursor number of table holding column
+ ** TK_REGISTER: register number
+ ** TK_TRIGGER: 1 -> new, 0 -> old
+ ** EP_Unlikely: 134217728 times likelihood
+ ** TK_SELECT: 1st register of result vector */
+ ynVar iColumn; /* TK_COLUMN: column index. -1 for rowid.
+ ** TK_VARIABLE: variable number (always >= 1).
+ ** TK_SELECT_COLUMN: column of the result vector */
+ i16 iAgg; /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
+ i16 iRightJoinTable; /* If EP_FromJoin, the right table of the join */
+ u8 op2; /* TK_REGISTER: original value of Expr.op
+ ** TK_COLUMN: the value of p5 for OP_Column
+ ** TK_AGG_FUNCTION: nesting depth */
+ AggInfo *pAggInfo; /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
+ Table *pTab; /* Table for TK_COLUMN expressions. Can be NULL
+ ** for a column of an index on an expression */
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ Window *pWin; /* Window definition for window functions */
+#endif
+};
+
+/*
+** The following are the meanings of bits in the Expr.flags field.
+*/
+#define EP_FromJoin 0x000001 /* Originates in ON/USING clause of outer join */
+#define EP_Agg 0x000002 /* Contains one or more aggregate functions */
+#define EP_HasFunc 0x000004 /* Contains one or more functions of any kind */
+#define EP_FixedCol 0x000008 /* TK_Column with a known fixed value */
+#define EP_Distinct 0x000010 /* Aggregate function with DISTINCT keyword */
+#define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
+#define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
+#define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
+#define EP_Collate 0x000100 /* Tree contains a TK_COLLATE operator */
+#define EP_Generic 0x000200 /* Ignore COLLATE or affinity on this tree */
+#define EP_IntValue 0x000400 /* Integer value contained in u.iValue */
+#define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
+#define EP_Skip 0x001000 /* COLLATE, AS, or UNLIKELY */
+#define EP_Reduced 0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
+#define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
+#define EP_Static 0x008000 /* Held in memory not obtained from malloc() */
+#define EP_MemToken 0x010000 /* Need to sqlite3DbFree() Expr.zToken */
+#define EP_NoReduce 0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
+#define EP_Unlikely 0x040000 /* unlikely() or likelihood() function */
+#define EP_ConstFunc 0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
+#define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
+#define EP_Subquery 0x200000 /* Tree contains a TK_SELECT operator */
+#define EP_Alias 0x400000 /* Is an alias for a result set column */
+#define EP_Leaf 0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
+
+/*
+** The EP_Propagate mask is a set of properties that automatically propagate
+** upwards into parent nodes.
+*/
+#define EP_Propagate (EP_Collate|EP_Subquery|EP_HasFunc)
+
+/*
+** These macros can be used to test, set, or clear bits in the
+** Expr.flags field.
+*/
+#define ExprHasProperty(E,P) (((E)->flags&(P))!=0)
+#define ExprHasAllProperty(E,P) (((E)->flags&(P))==(P))
+#define ExprSetProperty(E,P) (E)->flags|=(P)
+#define ExprClearProperty(E,P) (E)->flags&=~(P)
+
+/* The ExprSetVVAProperty() macro is used for Verification, Validation,
+** and Accreditation only. It works like ExprSetProperty() during VVA
+** processes but is a no-op for delivery.
+*/
+#ifdef SQLITE_DEBUG
+# define ExprSetVVAProperty(E,P) (E)->flags|=(P)
+#else
+# define ExprSetVVAProperty(E,P)
+#endif
+
+/*
+** Macros to determine the number of bytes required by a normal Expr
+** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
+** and an Expr struct with the EP_TokenOnly flag set.
+*/
+#define EXPR_FULLSIZE sizeof(Expr) /* Full size */
+#define EXPR_REDUCEDSIZE offsetof(Expr,iTable) /* Common features */
+#define EXPR_TOKENONLYSIZE offsetof(Expr,pLeft) /* Fewer features */
+
+/*
+** Flags passed to the sqlite3ExprDup() function. See the header comment
+** above sqlite3ExprDup() for details.
+*/
+#define EXPRDUP_REDUCE 0x0001 /* Used reduced-size Expr nodes */
+
+/*
+** A list of expressions. Each expression may optionally have a
+** name. An expr/name combination can be used in several ways, such
+** as the list of "expr AS ID" fields following a "SELECT" or in the
+** list of "ID = expr" items in an UPDATE. A list of expressions can
+** also be used as the argument to a function, in which case the a.zName
+** field is not used.
+**
+** By default the Expr.zSpan field holds a human-readable description of
+** the expression that is used in the generation of error messages and
+** column labels. In this case, Expr.zSpan is typically the text of a
+** column expression as it exists in a SELECT statement. However, if
+** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
+** of the result column in the form: DATABASE.TABLE.COLUMN. This later
+** form is used for name resolution with nested FROM clauses.
+*/
+struct ExprList {
+ int nExpr; /* Number of expressions on the list */
+ struct ExprList_item { /* For each expression in the list */
+ Expr *pExpr; /* The parse tree for this expression */
+ char *zName; /* Token associated with this expression */
+ char *zSpan; /* Original text of the expression */
+ u8 sortOrder; /* 1 for DESC or 0 for ASC */
+ unsigned done :1; /* A flag to indicate when processing is finished */
+ unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
+ unsigned reusable :1; /* Constant expression is reusable */
+ unsigned bSorterRef :1; /* Defer evaluation until after sorting */
+ union {
+ struct {
+ u16 iOrderByCol; /* For ORDER BY, column number in result set */
+ u16 iAlias; /* Index into Parse.aAlias[] for zName */
+ } x;
+ int iConstExprReg; /* Register in which Expr value is cached */
+ } u;
+ } a[1]; /* One slot for each expression in the list */
+};
+
+/*
+** An instance of this structure can hold a simple list of identifiers,
+** such as the list "a,b,c" in the following statements:
+**
+** INSERT INTO t(a,b,c) VALUES ...;
+** CREATE INDEX idx ON t(a,b,c);
+** CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
+**
+** The IdList.a.idx field is used when the IdList represents the list of
+** column names after a table name in an INSERT statement. In the statement
+**
+** INSERT INTO t(a,b,c) ...
+**
+** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
+*/
+struct IdList {
+ struct IdList_item {
+ char *zName; /* Name of the identifier */
+ int idx; /* Index in some Table.aCol[] of a column named zName */
+ } *a;
+ int nId; /* Number of identifiers on the list */
+};
+
+/*
+** The following structure describes the FROM clause of a SELECT statement.
+** Each table or subquery in the FROM clause is a separate element of
+** the SrcList.a[] array.
+**
+** With the addition of multiple database support, the following structure
+** can also be used to describe a particular table such as the table that
+** is modified by an INSERT, DELETE, or UPDATE statement. In standard SQL,
+** such a table must be a simple name: ID. But in SQLite, the table can
+** now be identified by a database name, a dot, then the table name: ID.ID.
+**
+** The jointype starts out showing the join type between the current table
+** and the next table on the list. The parser builds the list this way.
+** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
+** jointype expresses the join between the table and the previous table.
+**
+** In the colUsed field, the high-order bit (bit 63) is set if the table
+** contains more than 63 columns and the 64-th or later column is used.
+*/
+struct SrcList {
+ int nSrc; /* Number of tables or subqueries in the FROM clause */
+ u32 nAlloc; /* Number of entries allocated in a[] below */
+ struct SrcList_item {
+ Schema *pSchema; /* Schema to which this item is fixed */
+ char *zDatabase; /* Name of database holding this table */
+ char *zName; /* Name of the table */
+ char *zAlias; /* The "B" part of a "A AS B" phrase. zName is the "A" */
+ Table *pTab; /* An SQL table corresponding to zName */
+ Select *pSelect; /* A SELECT statement used in place of a table name */
+ int addrFillSub; /* Address of subroutine to manifest a subquery */
+ int regReturn; /* Register holding return address of addrFillSub */
+ int regResult; /* Registers holding results of a co-routine */
+ struct {
+ u8 jointype; /* Type of join between this table and the previous */
+ unsigned notIndexed :1; /* True if there is a NOT INDEXED clause */
+ unsigned isIndexedBy :1; /* True if there is an INDEXED BY clause */
+ unsigned isTabFunc :1; /* True if table-valued-function syntax */
+ unsigned isCorrelated :1; /* True if sub-query is correlated */
+ unsigned viaCoroutine :1; /* Implemented as a co-routine */
+ unsigned isRecursive :1; /* True for recursive reference in WITH */
+ } fg;
+ int iCursor; /* The VDBE cursor number used to access this table */
+ Expr *pOn; /* The ON clause of a join */
+ IdList *pUsing; /* The USING clause of a join */
+ Bitmask colUsed; /* Bit N (1<" clause */
+ ExprList *pFuncArg; /* Arguments to table-valued-function */
+ } u1;
+ Index *pIBIndex; /* Index structure corresponding to u1.zIndexedBy */
+ } a[1]; /* One entry for each identifier on the list */
+};
+
+/*
+** Permitted values of the SrcList.a.jointype field
+*/
+#define JT_INNER 0x0001 /* Any kind of inner or cross join */
+#define JT_CROSS 0x0002 /* Explicit use of the CROSS keyword */
+#define JT_NATURAL 0x0004 /* True for a "natural" join */
+#define JT_LEFT 0x0008 /* Left outer join */
+#define JT_RIGHT 0x0010 /* Right outer join */
+#define JT_OUTER 0x0020 /* The "OUTER" keyword is present */
+#define JT_ERROR 0x0040 /* unknown or unsupported join type */
+
+
+/*
+** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
+** and the WhereInfo.wctrlFlags member.
+**
+** Value constraints (enforced via assert()):
+** WHERE_USE_LIMIT == SF_FixedLimit
+*/
+#define WHERE_ORDERBY_NORMAL 0x0000 /* No-op */
+#define WHERE_ORDERBY_MIN 0x0001 /* ORDER BY processing for min() func */
+#define WHERE_ORDERBY_MAX 0x0002 /* ORDER BY processing for max() func */
+#define WHERE_ONEPASS_DESIRED 0x0004 /* Want to do one-pass UPDATE/DELETE */
+#define WHERE_ONEPASS_MULTIROW 0x0008 /* ONEPASS is ok with multiple rows */
+#define WHERE_DUPLICATES_OK 0x0010 /* Ok to return a row more than once */
+#define WHERE_OR_SUBCLAUSE 0x0020 /* Processing a sub-WHERE as part of
+ ** the OR optimization */
+#define WHERE_GROUPBY 0x0040 /* pOrderBy is really a GROUP BY */
+#define WHERE_DISTINCTBY 0x0080 /* pOrderby is really a DISTINCT clause */
+#define WHERE_WANT_DISTINCT 0x0100 /* All output needs to be distinct */
+#define WHERE_SORTBYGROUP 0x0200 /* Support sqlite3WhereIsSorted() */
+#define WHERE_SEEK_TABLE 0x0400 /* Do not defer seeks on main table */
+#define WHERE_ORDERBY_LIMIT 0x0800 /* ORDERBY+LIMIT on the inner loop */
+#define WHERE_SEEK_UNIQ_TABLE 0x1000 /* Do not defer seeks if unique */
+ /* 0x2000 not currently used */
+#define WHERE_USE_LIMIT 0x4000 /* Use the LIMIT in cost estimates */
+ /* 0x8000 not currently used */
+
+/* Allowed return values from sqlite3WhereIsDistinct()
+*/
+#define WHERE_DISTINCT_NOOP 0 /* DISTINCT keyword not used */
+#define WHERE_DISTINCT_UNIQUE 1 /* No duplicates */
+#define WHERE_DISTINCT_ORDERED 2 /* All duplicates are adjacent */
+#define WHERE_DISTINCT_UNORDERED 3 /* Duplicates are scattered */
+
+/*
+** A NameContext defines a context in which to resolve table and column
+** names. The context consists of a list of tables (the pSrcList) field and
+** a list of named expression (pEList). The named expression list may
+** be NULL. The pSrc corresponds to the FROM clause of a SELECT or
+** to the table being operated on by INSERT, UPDATE, or DELETE. The
+** pEList corresponds to the result set of a SELECT and is NULL for
+** other statements.
+**
+** NameContexts can be nested. When resolving names, the inner-most
+** context is searched first. If no match is found, the next outer
+** context is checked. If there is still no match, the next context
+** is checked. This process continues until either a match is found
+** or all contexts are check. When a match is found, the nRef member of
+** the context containing the match is incremented.
+**
+** Each subquery gets a new NameContext. The pNext field points to the
+** NameContext in the parent query. Thus the process of scanning the
+** NameContext list corresponds to searching through successively outer
+** subqueries looking for a match.
+*/
+struct NameContext {
+ Parse *pParse; /* The parser */
+ SrcList *pSrcList; /* One or more tables used to resolve names */
+ union {
+ ExprList *pEList; /* Optional list of result-set columns */
+ AggInfo *pAggInfo; /* Information about aggregates at this level */
+ Upsert *pUpsert; /* ON CONFLICT clause information from an upsert */
+ } uNC;
+ NameContext *pNext; /* Next outer name context. NULL for outermost */
+ int nRef; /* Number of names resolved by this context */
+ int nErr; /* Number of errors encountered while resolving names */
+ u16 ncFlags; /* Zero or more NC_* flags defined below */
+ Select *pWinSelect; /* SELECT statement for any window functions */
+};
+
+/*
+** Allowed values for the NameContext, ncFlags field.
+**
+** Value constraints (all checked via assert()):
+** NC_HasAgg == SF_HasAgg
+** NC_MinMaxAgg == SF_MinMaxAgg == SQLITE_FUNC_MINMAX
+**
+*/
+#define NC_AllowAgg 0x0001 /* Aggregate functions are allowed here */
+#define NC_PartIdx 0x0002 /* True if resolving a partial index WHERE */
+#define NC_IsCheck 0x0004 /* True if resolving names in a CHECK constraint */
+#define NC_InAggFunc 0x0008 /* True if analyzing arguments to an agg func */
+#define NC_HasAgg 0x0010 /* One or more aggregate functions seen */
+#define NC_IdxExpr 0x0020 /* True if resolving columns of CREATE INDEX */
+#define NC_VarSelect 0x0040 /* A correlated subquery has been seen */
+#define NC_UEList 0x0080 /* True if uNC.pEList is used */
+#define NC_UAggInfo 0x0100 /* True if uNC.pAggInfo is used */
+#define NC_UUpsert 0x0200 /* True if uNC.pUpsert is used */
+#define NC_MinMaxAgg 0x1000 /* min/max aggregates seen. See note above */
+#define NC_Complex 0x2000 /* True if a function or subquery seen */
+#define NC_AllowWin 0x4000 /* Window functions are allowed here */
+
+/*
+** An instance of the following object describes a single ON CONFLICT
+** clause in an upsert.
+**
+** The pUpsertTarget field is only set if the ON CONFLICT clause includes
+** conflict-target clause. (In "ON CONFLICT(a,b)" the "(a,b)" is the
+** conflict-target clause.) The pUpsertTargetWhere is the optional
+** WHERE clause used to identify partial unique indexes.
+**
+** pUpsertSet is the list of column=expr terms of the UPDATE statement.
+** The pUpsertSet field is NULL for a ON CONFLICT DO NOTHING. The
+** pUpsertWhere is the WHERE clause for the UPDATE and is NULL if the
+** WHERE clause is omitted.
+*/
+struct Upsert {
+ ExprList *pUpsertTarget; /* Optional description of conflicting index */
+ Expr *pUpsertTargetWhere; /* WHERE clause for partial index targets */
+ ExprList *pUpsertSet; /* The SET clause from an ON CONFLICT UPDATE */
+ Expr *pUpsertWhere; /* WHERE clause for the ON CONFLICT UPDATE */
+ /* The fields above comprise the parse tree for the upsert clause.
+ ** The fields below are used to transfer information from the INSERT
+ ** processing down into the UPDATE processing while generating code.
+ ** Upsert owns the memory allocated above, but not the memory below. */
+ Index *pUpsertIdx; /* Constraint that pUpsertTarget identifies */
+ SrcList *pUpsertSrc; /* Table to be updated */
+ int regData; /* First register holding array of VALUES */
+ int iDataCur; /* Index of the data cursor */
+ int iIdxCur; /* Index of the first index cursor */
+};
+
+/*
+** An instance of the following structure contains all information
+** needed to generate code for a single SELECT statement.
+**
+** See the header comment on the computeLimitRegisters() routine for a
+** detailed description of the meaning of the iLimit and iOffset fields.
+**
+** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
+** These addresses must be stored so that we can go back and fill in
+** the P4_KEYINFO and P2 parameters later. Neither the KeyInfo nor
+** the number of columns in P2 can be computed at the same time
+** as the OP_OpenEphm instruction is coded because not
+** enough information about the compound query is known at that point.
+** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
+** for the result set. The KeyInfo for addrOpenEphm[2] contains collating
+** sequences for the ORDER BY clause.
+*/
+struct Select {
+ ExprList *pEList; /* The fields of the result */
+ u8 op; /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
+ LogEst nSelectRow; /* Estimated number of result rows */
+ u32 selFlags; /* Various SF_* values */
+ int iLimit, iOffset; /* Memory registers holding LIMIT & OFFSET counters */
+ u32 selId; /* Unique identifier number for this SELECT */
+ int addrOpenEphm[2]; /* OP_OpenEphem opcodes related to this select */
+ SrcList *pSrc; /* The FROM clause */
+ Expr *pWhere; /* The WHERE clause */
+ ExprList *pGroupBy; /* The GROUP BY clause */
+ Expr *pHaving; /* The HAVING clause */
+ ExprList *pOrderBy; /* The ORDER BY clause */
+ Select *pPrior; /* Prior select in a compound select statement */
+ Select *pNext; /* Next select to the left in a compound */
+ Expr *pLimit; /* LIMIT expression. NULL means not used. */
+ With *pWith; /* WITH clause attached to this select. Or NULL. */
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ Window *pWin; /* List of window functions */
+ Window *pWinDefn; /* List of named window definitions */
+#endif
+};
+
+/*
+** Allowed values for Select.selFlags. The "SF" prefix stands for
+** "Select Flag".
+**
+** Value constraints (all checked via assert())
+** SF_HasAgg == NC_HasAgg
+** SF_MinMaxAgg == NC_MinMaxAgg == SQLITE_FUNC_MINMAX
+** SF_FixedLimit == WHERE_USE_LIMIT
+*/
+#define SF_Distinct 0x00001 /* Output should be DISTINCT */
+#define SF_All 0x00002 /* Includes the ALL keyword */
+#define SF_Resolved 0x00004 /* Identifiers have been resolved */
+#define SF_Aggregate 0x00008 /* Contains agg functions or a GROUP BY */
+#define SF_HasAgg 0x00010 /* Contains aggregate functions */
+#define SF_UsesEphemeral 0x00020 /* Uses the OpenEphemeral opcode */
+#define SF_Expanded 0x00040 /* sqlite3SelectExpand() called on this */
+#define SF_HasTypeInfo 0x00080 /* FROM subqueries have Table metadata */
+#define SF_Compound 0x00100 /* Part of a compound query */
+#define SF_Values 0x00200 /* Synthesized from VALUES clause */
+#define SF_MultiValue 0x00400 /* Single VALUES term with multiple rows */
+#define SF_NestedFrom 0x00800 /* Part of a parenthesized FROM clause */
+#define SF_MinMaxAgg 0x01000 /* Aggregate containing min() or max() */
+#define SF_Recursive 0x02000 /* The recursive part of a recursive CTE */
+#define SF_FixedLimit 0x04000 /* nSelectRow set by a constant LIMIT */
+#define SF_MaybeConvert 0x08000 /* Need convertCompoundSelectToSubquery() */
+#define SF_Converted 0x10000 /* By convertCompoundSelectToSubquery() */
+#define SF_IncludeHidden 0x20000 /* Include hidden columns in output */
+#define SF_ComplexResult 0x40000 /* Result contains subquery or function */
+
+/*
+** The results of a SELECT can be distributed in several ways, as defined
+** by one of the following macros. The "SRT" prefix means "SELECT Result
+** Type".
+**
+** SRT_Union Store results as a key in a temporary index
+** identified by pDest->iSDParm.
+**
+** SRT_Except Remove results from the temporary index pDest->iSDParm.
+**
+** SRT_Exists Store a 1 in memory cell pDest->iSDParm if the result
+** set is not empty.
+**
+** SRT_Discard Throw the results away. This is used by SELECT
+** statements within triggers whose only purpose is
+** the side-effects of functions.
+**
+** All of the above are free to ignore their ORDER BY clause. Those that
+** follow must honor the ORDER BY clause.
+**
+** SRT_Output Generate a row of output (using the OP_ResultRow
+** opcode) for each row in the result set.
+**
+** SRT_Mem Only valid if the result is a single column.
+** Store the first column of the first result row
+** in register pDest->iSDParm then abandon the rest
+** of the query. This destination implies "LIMIT 1".
+**
+** SRT_Set The result must be a single column. Store each
+** row of result as the key in table pDest->iSDParm.
+** Apply the affinity pDest->affSdst before storing
+** results. Used to implement "IN (SELECT ...)".
+**
+** SRT_EphemTab Create an temporary table pDest->iSDParm and store
+** the result there. The cursor is left open after
+** returning. This is like SRT_Table except that
+** this destination uses OP_OpenEphemeral to create
+** the table first.
+**
+** SRT_Coroutine Generate a co-routine that returns a new row of
+** results each time it is invoked. The entry point
+** of the co-routine is stored in register pDest->iSDParm
+** and the result row is stored in pDest->nDest registers
+** starting with pDest->iSdst.
+**
+** SRT_Table Store results in temporary table pDest->iSDParm.
+** SRT_Fifo This is like SRT_EphemTab except that the table
+** is assumed to already be open. SRT_Fifo has
+** the additional property of being able to ignore
+** the ORDER BY clause.
+**
+** SRT_DistFifo Store results in a temporary table pDest->iSDParm.
+** But also use temporary table pDest->iSDParm+1 as
+** a record of all prior results and ignore any duplicate
+** rows. Name means: "Distinct Fifo".
+**
+** SRT_Queue Store results in priority queue pDest->iSDParm (really
+** an index). Append a sequence number so that all entries
+** are distinct.
+**
+** SRT_DistQueue Store results in priority queue pDest->iSDParm only if
+** the same record has never been stored before. The
+** index at pDest->iSDParm+1 hold all prior stores.
+*/
+#define SRT_Union 1 /* Store result as keys in an index */
+#define SRT_Except 2 /* Remove result from a UNION index */
+#define SRT_Exists 3 /* Store 1 if the result is not empty */
+#define SRT_Discard 4 /* Do not save the results anywhere */
+#define SRT_Fifo 5 /* Store result as data with an automatic rowid */
+#define SRT_DistFifo 6 /* Like SRT_Fifo, but unique results only */
+#define SRT_Queue 7 /* Store result in an queue */
+#define SRT_DistQueue 8 /* Like SRT_Queue, but unique results only */
+
+/* The ORDER BY clause is ignored for all of the above */
+#define IgnorableOrderby(X) ((X->eDest)<=SRT_DistQueue)
+
+#define SRT_Output 9 /* Output each row of result */
+#define SRT_Mem 10 /* Store result in a memory cell */
+#define SRT_Set 11 /* Store results as keys in an index */
+#define SRT_EphemTab 12 /* Create transient tab and store like SRT_Table */
+#define SRT_Coroutine 13 /* Generate a single row of result */
+#define SRT_Table 14 /* Store result as data with an automatic rowid */
+
+/*
+** An instance of this object describes where to put of the results of
+** a SELECT statement.
+*/
+struct SelectDest {
+ u8 eDest; /* How to dispose of the results. On of SRT_* above. */
+ int iSDParm; /* A parameter used by the eDest disposal method */
+ int iSdst; /* Base register where results are written */
+ int nSdst; /* Number of registers allocated */
+ char *zAffSdst; /* Affinity used when eDest==SRT_Set */
+ ExprList *pOrderBy; /* Key columns for SRT_Queue and SRT_DistQueue */
+};
+
+/*
+** During code generation of statements that do inserts into AUTOINCREMENT
+** tables, the following information is attached to the Table.u.autoInc.p
+** pointer of each autoincrement table to record some side information that
+** the code generator needs. We have to keep per-table autoincrement
+** information in case inserts are done within triggers. Triggers do not
+** normally coordinate their activities, but we do need to coordinate the
+** loading and saving of autoincrement information.
+*/
+struct AutoincInfo {
+ AutoincInfo *pNext; /* Next info block in a list of them all */
+ Table *pTab; /* Table this info block refers to */
+ int iDb; /* Index in sqlite3.aDb[] of database holding pTab */
+ int regCtr; /* Memory register holding the rowid counter */
+};
+
+/*
+** At least one instance of the following structure is created for each
+** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
+** statement. All such objects are stored in the linked list headed at
+** Parse.pTriggerPrg and deleted once statement compilation has been
+** completed.
+**
+** A Vdbe sub-program that implements the body and WHEN clause of trigger
+** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
+** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
+** The Parse.pTriggerPrg list never contains two entries with the same
+** values for both pTrigger and orconf.
+**
+** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
+** accessed (or set to 0 for triggers fired as a result of INSERT
+** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
+** a mask of new.* columns used by the program.
+*/
+struct TriggerPrg {
+ Trigger *pTrigger; /* Trigger this program was coded from */
+ TriggerPrg *pNext; /* Next entry in Parse.pTriggerPrg list */
+ SubProgram *pProgram; /* Program implementing pTrigger/orconf */
+ int orconf; /* Default ON CONFLICT policy */
+ u32 aColmask[2]; /* Masks of old.*, new.* columns accessed */
+};
+
+/*
+** The yDbMask datatype for the bitmask of all attached databases.
+*/
+#if SQLITE_MAX_ATTACHED>30
+ typedef unsigned char yDbMask[(SQLITE_MAX_ATTACHED+9)/8];
+# define DbMaskTest(M,I) (((M)[(I)/8]&(1<<((I)&7)))!=0)
+# define DbMaskZero(M) memset((M),0,sizeof(M))
+# define DbMaskSet(M,I) (M)[(I)/8]|=(1<<((I)&7))
+# define DbMaskAllZero(M) sqlite3DbMaskAllZero(M)
+# define DbMaskNonZero(M) (sqlite3DbMaskAllZero(M)==0)
+#else
+ typedef unsigned int yDbMask;
+# define DbMaskTest(M,I) (((M)&(((yDbMask)1)<<(I)))!=0)
+# define DbMaskZero(M) (M)=0
+# define DbMaskSet(M,I) (M)|=(((yDbMask)1)<<(I))
+# define DbMaskAllZero(M) (M)==0
+# define DbMaskNonZero(M) (M)!=0
+#endif
+
+/*
+** An SQL parser context. A copy of this structure is passed through
+** the parser and down into all the parser action routine in order to
+** carry around information that is global to the entire parse.
+**
+** The structure is divided into two parts. When the parser and code
+** generate call themselves recursively, the first part of the structure
+** is constant but the second part is reset at the beginning and end of
+** each recursion.
+**
+** The nTableLock and aTableLock variables are only used if the shared-cache
+** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
+** used to store the set of table-locks required by the statement being
+** compiled. Function sqlite3TableLock() is used to add entries to the
+** list.
+*/
+struct Parse {
+ sqlite3 *db; /* The main database structure */
+ char *zErrMsg; /* An error message */
+ Vdbe *pVdbe; /* An engine for executing database bytecode */
+ int rc; /* Return code from execution */
+ u8 colNamesSet; /* TRUE after OP_ColumnName has been issued to pVdbe */
+ u8 checkSchema; /* Causes schema cookie check after an error */
+ u8 nested; /* Number of nested calls to the parser/code generator */
+ u8 nTempReg; /* Number of temporary registers in aTempReg[] */
+ u8 isMultiWrite; /* True if statement may modify/insert multiple rows */
+ u8 mayAbort; /* True if statement may throw an ABORT exception */
+ u8 hasCompound; /* Need to invoke convertCompoundSelectToSubquery() */
+ u8 okConstFactor; /* OK to factor out constants */
+ u8 disableLookaside; /* Number of times lookaside has been disabled */
+ int nRangeReg; /* Size of the temporary register block */
+ int iRangeReg; /* First register in temporary register block */
+ int nErr; /* Number of errors seen */
+ int nTab; /* Number of previously allocated VDBE cursors */
+ int nMem; /* Number of memory cells used so far */
+ int nOpAlloc; /* Number of slots allocated for Vdbe.aOp[] */
+ int szOpAlloc; /* Bytes of memory space allocated for Vdbe.aOp[] */
+ int iSelfTab; /* Table associated with an index on expr, or negative
+ ** of the base register during check-constraint eval */
+ int nLabel; /* Number of labels used */
+ int *aLabel; /* Space to hold the labels */
+ ExprList *pConstExpr;/* Constant expressions */
+ Token constraintName;/* Name of the constraint currently being parsed */
+ yDbMask writeMask; /* Start a write transaction on these databases */
+ yDbMask cookieMask; /* Bitmask of schema verified databases */
+ int regRowid; /* Register holding rowid of CREATE TABLE entry */
+ int regRoot; /* Register holding root page number for new objects */
+ int nMaxArg; /* Max args passed to user function by sub-program */
+ int nSelect; /* Number of SELECT stmts. Counter for Select.selId */
+#ifndef SQLITE_OMIT_SHARED_CACHE
+ int nTableLock; /* Number of locks in aTableLock */
+ TableLock *aTableLock; /* Required table locks for shared-cache mode */
+#endif
+ AutoincInfo *pAinc; /* Information about AUTOINCREMENT counters */
+ Parse *pToplevel; /* Parse structure for main program (or NULL) */
+ Table *pTriggerTab; /* Table triggers are being coded for */
+ int addrCrTab; /* Address of OP_CreateBtree opcode on CREATE TABLE */
+ u32 nQueryLoop; /* Est number of iterations of a query (10*log2(N)) */
+ u32 oldmask; /* Mask of old.* columns referenced */
+ u32 newmask; /* Mask of new.* columns referenced */
+ u8 eTriggerOp; /* TK_UPDATE, TK_INSERT or TK_DELETE */
+ u8 eOrconf; /* Default ON CONFLICT policy for trigger steps */
+ u8 disableTriggers; /* True to disable triggers */
+
+ /**************************************************************************
+ ** Fields above must be initialized to zero. The fields that follow,
+ ** down to the beginning of the recursive section, do not need to be
+ ** initialized as they will be set before being used. The boundary is
+ ** determined by offsetof(Parse,aTempReg).
+ **************************************************************************/
+
+ int aTempReg[8]; /* Holding area for temporary registers */
+ Token sNameToken; /* Token with unqualified schema object name */
+
+ /************************************************************************
+ ** Above is constant between recursions. Below is reset before and after
+ ** each recursion. The boundary between these two regions is determined
+ ** using offsetof(Parse,sLastToken) so the sLastToken field must be the
+ ** first field in the recursive region.
+ ************************************************************************/
+
+ Token sLastToken; /* The last token parsed */
+ ynVar nVar; /* Number of '?' variables seen in the SQL so far */
+ u8 iPkSortOrder; /* ASC or DESC for INTEGER PRIMARY KEY */
+ u8 explain; /* True if the EXPLAIN flag is found on the query */
+#if !(defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_OMIT_ALTERTABLE))
+ u8 eParseMode; /* PARSE_MODE_XXX constant */
+#endif
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+ int nVtabLock; /* Number of virtual tables to lock */
+#endif
+ int nHeight; /* Expression tree height of current sub-select */
+#ifndef SQLITE_OMIT_EXPLAIN
+ int addrExplain; /* Address of current OP_Explain opcode */
+#endif
+ VList *pVList; /* Mapping between variable names and numbers */
+ Vdbe *pReprepare; /* VM being reprepared (sqlite3Reprepare()) */
+ const char *zTail; /* All SQL text past the last semicolon parsed */
+ Table *pNewTable; /* A table being constructed by CREATE TABLE */
+ Index *pNewIndex; /* An index being constructed by CREATE INDEX */
+ Trigger *pNewTrigger; /* Trigger under construct by a CREATE TRIGGER */
+ const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+ Token sArg; /* Complete text of a module argument */
+ Table **apVtabLock; /* Pointer to virtual tables needing locking */
+#endif
+ Table *pZombieTab; /* List of Table objects to delete after code gen */
+ TriggerPrg *pTriggerPrg; /* Linked list of coded triggers */
+ With *pWith; /* Current WITH clause, or NULL */
+ With *pWithToFree; /* Free this WITH object at the end of the parse */
+#ifndef SQLITE_OMIT_ALTERTABLE
+ RenameToken *pRename; /* Tokens subject to renaming by ALTER TABLE */
+#endif
+};
+
+#define PARSE_MODE_NORMAL 0
+#define PARSE_MODE_DECLARE_VTAB 1
+#define PARSE_MODE_RENAME_COLUMN 2
+#define PARSE_MODE_RENAME_TABLE 3
+
+/*
+** Sizes and pointers of various parts of the Parse object.
+*/
+#define PARSE_HDR_SZ offsetof(Parse,aTempReg) /* Recursive part w/o aColCache*/
+#define PARSE_RECURSE_SZ offsetof(Parse,sLastToken) /* Recursive part */
+#define PARSE_TAIL_SZ (sizeof(Parse)-PARSE_RECURSE_SZ) /* Non-recursive part */
+#define PARSE_TAIL(X) (((char*)(X))+PARSE_RECURSE_SZ) /* Pointer to tail */
+
+/*
+** Return true if currently inside an sqlite3_declare_vtab() call.
+*/
+#ifdef SQLITE_OMIT_VIRTUALTABLE
+ #define IN_DECLARE_VTAB 0
+#else
+ #define IN_DECLARE_VTAB (pParse->eParseMode==PARSE_MODE_DECLARE_VTAB)
+#endif
+
+#if defined(SQLITE_OMIT_ALTERTABLE)
+ #define IN_RENAME_OBJECT 0
+#else
+ #define IN_RENAME_OBJECT (pParse->eParseMode>=PARSE_MODE_RENAME_COLUMN)
+#endif
+
+#if defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_OMIT_ALTERTABLE)
+ #define IN_SPECIAL_PARSE 0
+#else
+ #define IN_SPECIAL_PARSE (pParse->eParseMode!=PARSE_MODE_NORMAL)
+#endif
+
+/*
+** An instance of the following structure can be declared on a stack and used
+** to save the Parse.zAuthContext value so that it can be restored later.
+*/
+struct AuthContext {
+ const char *zAuthContext; /* Put saved Parse.zAuthContext here */
+ Parse *pParse; /* The Parse structure */
+};
+
+/*
+** Bitfield flags for P5 value in various opcodes.
+**
+** Value constraints (enforced via assert()):
+** OPFLAG_LENGTHARG == SQLITE_FUNC_LENGTH
+** OPFLAG_TYPEOFARG == SQLITE_FUNC_TYPEOF
+** OPFLAG_BULKCSR == BTREE_BULKLOAD
+** OPFLAG_SEEKEQ == BTREE_SEEK_EQ
+** OPFLAG_FORDELETE == BTREE_FORDELETE
+** OPFLAG_SAVEPOSITION == BTREE_SAVEPOSITION
+** OPFLAG_AUXDELETE == BTREE_AUXDELETE
+*/
+#define OPFLAG_NCHANGE 0x01 /* OP_Insert: Set to update db->nChange */
+ /* Also used in P2 (not P5) of OP_Delete */
+#define OPFLAG_NOCHNG 0x01 /* OP_VColumn nochange for UPDATE */
+#define OPFLAG_EPHEM 0x01 /* OP_Column: Ephemeral output is ok */
+#define OPFLAG_LASTROWID 0x20 /* Set to update db->lastRowid */
+#define OPFLAG_ISUPDATE 0x04 /* This OP_Insert is an sql UPDATE */
+#define OPFLAG_APPEND 0x08 /* This is likely to be an append */
+#define OPFLAG_USESEEKRESULT 0x10 /* Try to avoid a seek in BtreeInsert() */
+#define OPFLAG_ISNOOP 0x40 /* OP_Delete does pre-update-hook only */
+#define OPFLAG_LENGTHARG 0x40 /* OP_Column only used for length() */
+#define OPFLAG_TYPEOFARG 0x80 /* OP_Column only used for typeof() */
+#define OPFLAG_BULKCSR 0x01 /* OP_Open** used to open bulk cursor */
+#define OPFLAG_SEEKEQ 0x02 /* OP_Open** cursor uses EQ seek only */
+#define OPFLAG_FORDELETE 0x08 /* OP_Open should use BTREE_FORDELETE */
+#define OPFLAG_P2ISREG 0x10 /* P2 to OP_Open** is a register number */
+#define OPFLAG_PERMUTE 0x01 /* OP_Compare: use the permutation */
+#define OPFLAG_SAVEPOSITION 0x02 /* OP_Delete/Insert: save cursor pos */
+#define OPFLAG_AUXDELETE 0x04 /* OP_Delete: index in a DELETE op */
+#define OPFLAG_NOCHNG_MAGIC 0x6d /* OP_MakeRecord: serialtype 10 is ok */
+
+/*
+ * Each trigger present in the database schema is stored as an instance of
+ * struct Trigger.
+ *
+ * Pointers to instances of struct Trigger are stored in two ways.
+ * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
+ * database). This allows Trigger structures to be retrieved by name.
+ * 2. All triggers associated with a single table form a linked list, using the
+ * pNext member of struct Trigger. A pointer to the first element of the
+ * linked list is stored as the "pTrigger" member of the associated
+ * struct Table.
+ *
+ * The "step_list" member points to the first element of a linked list
+ * containing the SQL statements specified as the trigger program.
+ */
+struct Trigger {
+ char *zName; /* The name of the trigger */
+ char *table; /* The table or view to which the trigger applies */
+ u8 op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT */
+ u8 tr_tm; /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
+ Expr *pWhen; /* The WHEN clause of the expression (may be NULL) */
+ IdList *pColumns; /* If this is an UPDATE OF trigger,
+ the is stored here */
+ Schema *pSchema; /* Schema containing the trigger */
+ Schema *pTabSchema; /* Schema containing the table */
+ TriggerStep *step_list; /* Link list of trigger program steps */
+ Trigger *pNext; /* Next trigger associated with the table */
+};
+
+/*
+** A trigger is either a BEFORE or an AFTER trigger. The following constants
+** determine which.
+**
+** If there are multiple triggers, you might of some BEFORE and some AFTER.
+** In that cases, the constants below can be ORed together.
+*/
+#define TRIGGER_BEFORE 1
+#define TRIGGER_AFTER 2
+
+/*
+ * An instance of struct TriggerStep is used to store a single SQL statement
+ * that is a part of a trigger-program.
+ *
+ * Instances of struct TriggerStep are stored in a singly linked list (linked
+ * using the "pNext" member) referenced by the "step_list" member of the
+ * associated struct Trigger instance. The first element of the linked list is
+ * the first step of the trigger-program.
+ *
+ * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
+ * "SELECT" statement. The meanings of the other members is determined by the
+ * value of "op" as follows:
+ *
+ * (op == TK_INSERT)
+ * orconf -> stores the ON CONFLICT algorithm
+ * pSelect -> If this is an INSERT INTO ... SELECT ... statement, then
+ * this stores a pointer to the SELECT statement. Otherwise NULL.
+ * zTarget -> Dequoted name of the table to insert into.
+ * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
+ * this stores values to be inserted. Otherwise NULL.
+ * pIdList -> If this is an INSERT INTO ... () VALUES ...
+ * statement, then this stores the column-names to be
+ * inserted into.
+ *
+ * (op == TK_DELETE)
+ * zTarget -> Dequoted name of the table to delete from.
+ * pWhere -> The WHERE clause of the DELETE statement if one is specified.
+ * Otherwise NULL.
+ *
+ * (op == TK_UPDATE)
+ * zTarget -> Dequoted name of the table to update.
+ * pWhere -> The WHERE clause of the UPDATE statement if one is specified.
+ * Otherwise NULL.
+ * pExprList -> A list of the columns to update and the expressions to update
+ * them to. See sqlite3Update() documentation of "pChanges"
+ * argument.
+ *
+ */
+struct TriggerStep {
+ u8 op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
+ u8 orconf; /* OE_Rollback etc. */
+ Trigger *pTrig; /* The trigger that this step is a part of */
+ Select *pSelect; /* SELECT statement or RHS of INSERT INTO SELECT ... */
+ char *zTarget; /* Target table for DELETE, UPDATE, INSERT */
+ Expr *pWhere; /* The WHERE clause for DELETE or UPDATE steps */
+ ExprList *pExprList; /* SET clause for UPDATE */
+ IdList *pIdList; /* Column names for INSERT */
+ Upsert *pUpsert; /* Upsert clauses on an INSERT */
+ char *zSpan; /* Original SQL text of this command */
+ TriggerStep *pNext; /* Next in the link-list */
+ TriggerStep *pLast; /* Last element in link-list. Valid for 1st elem only */
+};
+
+/*
+** The following structure contains information used by the sqliteFix...
+** routines as they walk the parse tree to make database references
+** explicit.
+*/
+typedef struct DbFixer DbFixer;
+struct DbFixer {
+ Parse *pParse; /* The parsing context. Error messages written here */
+ Schema *pSchema; /* Fix items to this schema */
+ int bVarOnly; /* Check for variable references only */
+ const char *zDb; /* Make sure all objects are contained in this database */
+ const char *zType; /* Type of the container - used for error messages */
+ const Token *pName; /* Name of the container - used for error messages */
+};
+
+/*
+** An objected used to accumulate the text of a string where we
+** do not necessarily know how big the string will be in the end.
+*/
+struct sqlite3_str {
+ sqlite3 *db; /* Optional database for lookaside. Can be NULL */
+ char *zText; /* The string collected so far */
+ u32 nAlloc; /* Amount of space allocated in zText */
+ u32 mxAlloc; /* Maximum allowed allocation. 0 for no malloc usage */
+ u32 nChar; /* Length of the string so far */
+ u8 accError; /* SQLITE_NOMEM or SQLITE_TOOBIG */
+ u8 printfFlags; /* SQLITE_PRINTF flags below */
+};
+#define SQLITE_PRINTF_INTERNAL 0x01 /* Internal-use-only converters allowed */
+#define SQLITE_PRINTF_SQLFUNC 0x02 /* SQL function arguments to VXPrintf */
+#define SQLITE_PRINTF_MALLOCED 0x04 /* True if xText is allocated space */
+
+#define isMalloced(X) (((X)->printfFlags & SQLITE_PRINTF_MALLOCED)!=0)
+
+
+/*
+** A pointer to this structure is used to communicate information
+** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
+*/
+typedef struct {
+ sqlite3 *db; /* The database being initialized */
+ char **pzErrMsg; /* Error message stored here */
+ int iDb; /* 0 for main database. 1 for TEMP, 2.. for ATTACHed */
+ int rc; /* Result code stored here */
+ u32 mInitFlags; /* Flags controlling error messages */
+} InitData;
+
+/*
+** Allowed values for mInitFlags
+*/
+#define INITFLAG_AlterTable 0x0001 /* This is a reparse after ALTER TABLE */
+
+/*
+** Structure containing global configuration data for the SQLite library.
+**
+** This structure also contains some state information.
+*/
+struct Sqlite3Config {
+ int bMemstat; /* True to enable memory status */
+ int bCoreMutex; /* True to enable core mutexing */
+ int bFullMutex; /* True to enable full mutexing */
+ int bOpenUri; /* True to interpret filenames as URIs */
+ int bUseCis; /* Use covering indices for full-scans */
+ int bSmallMalloc; /* Avoid large memory allocations if true */
+ int mxStrlen; /* Maximum string length */
+ int neverCorrupt; /* Database is always well-formed */
+ int szLookaside; /* Default lookaside buffer size */
+ int nLookaside; /* Default lookaside buffer count */
+ int nStmtSpill; /* Stmt-journal spill-to-disk threshold */
+ sqlite3_mem_methods m; /* Low-level memory allocation interface */
+ sqlite3_mutex_methods mutex; /* Low-level mutex interface */
+ sqlite3_pcache_methods2 pcache2; /* Low-level page-cache interface */
+ void *pHeap; /* Heap storage space */
+ int nHeap; /* Size of pHeap[] */
+ int mnReq, mxReq; /* Min and max heap requests sizes */
+ sqlite3_int64 szMmap; /* mmap() space per open file */
+ sqlite3_int64 mxMmap; /* Maximum value for szMmap */
+ void *pPage; /* Page cache memory */
+ int szPage; /* Size of each page in pPage[] */
+ int nPage; /* Number of pages in pPage[] */
+ int mxParserStack; /* maximum depth of the parser stack */
+ int sharedCacheEnabled; /* true if shared-cache mode enabled */
+ u32 szPma; /* Maximum Sorter PMA size */
+ /* The above might be initialized to non-zero. The following need to always
+ ** initially be zero, however. */
+ int isInit; /* True after initialization has finished */
+ int inProgress; /* True while initialization in progress */
+ int isMutexInit; /* True after mutexes are initialized */
+ int isMallocInit; /* True after malloc is initialized */
+ int isPCacheInit; /* True after malloc is initialized */
+ int nRefInitMutex; /* Number of users of pInitMutex */
+ sqlite3_mutex *pInitMutex; /* Mutex used by sqlite3_initialize() */
+ void (*xLog)(void*,int,const char*); /* Function for logging */
+ void *pLogArg; /* First argument to xLog() */
+#ifdef SQLITE_ENABLE_SQLLOG
+ void(*xSqllog)(void*,sqlite3*,const char*, int);
+ void *pSqllogArg;
+#endif
+#ifdef SQLITE_VDBE_COVERAGE
+ /* The following callback (if not NULL) is invoked on every VDBE branch
+ ** operation. Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
+ */
+ void (*xVdbeBranch)(void*,unsigned iSrcLine,u8 eThis,u8 eMx); /* Callback */
+ void *pVdbeBranchArg; /* 1st argument */
+#endif
+#ifndef SQLITE_UNTESTABLE
+ int (*xTestCallback)(int); /* Invoked by sqlite3FaultSim() */
+#endif
+ int bLocaltimeFault; /* True to fail localtime() calls */
+ int iOnceResetThreshold; /* When to reset OP_Once counters */
+ u32 szSorterRef; /* Min size in bytes to use sorter-refs */
+};
+
+/*
+** This macro is used inside of assert() statements to indicate that
+** the assert is only valid on a well-formed database. Instead of:
+**
+** assert( X );
+**
+** One writes:
+**
+** assert( X || CORRUPT_DB );
+**
+** CORRUPT_DB is true during normal operation. CORRUPT_DB does not indicate
+** that the database is definitely corrupt, only that it might be corrupt.
+** For most test cases, CORRUPT_DB is set to false using a special
+** sqlite3_test_control(). This enables assert() statements to prove
+** things that are always true for well-formed databases.
+*/
+#define CORRUPT_DB (sqlite3Config.neverCorrupt==0)
+
+/*
+** Context pointer passed down through the tree-walk.
+*/
+struct Walker {
+ Parse *pParse; /* Parser context. */
+ int (*xExprCallback)(Walker*, Expr*); /* Callback for expressions */
+ int (*xSelectCallback)(Walker*,Select*); /* Callback for SELECTs */
+ void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
+ int walkerDepth; /* Number of subqueries */
+ u8 eCode; /* A small processing code */
+ union { /* Extra data for callback */
+ NameContext *pNC; /* Naming context */
+ int n; /* A counter */
+ int iCur; /* A cursor number */
+ SrcList *pSrcList; /* FROM clause */
+ struct SrcCount *pSrcCount; /* Counting column references */
+ struct CCurHint *pCCurHint; /* Used by codeCursorHint() */
+ int *aiCol; /* array of column indexes */
+ struct IdxCover *pIdxCover; /* Check for index coverage */
+ struct IdxExprTrans *pIdxTrans; /* Convert idxed expr to column */
+ ExprList *pGroupBy; /* GROUP BY clause */
+ Select *pSelect; /* HAVING to WHERE clause ctx */
+ struct WindowRewrite *pRewrite; /* Window rewrite context */
+ struct WhereConst *pConst; /* WHERE clause constants */
+ struct RenameCtx *pRename; /* RENAME COLUMN context */
+ } u;
+};
+
+/* Forward declarations */
+SQLITE_PRIVATE int sqlite3WalkExpr(Walker*, Expr*);
+SQLITE_PRIVATE int sqlite3WalkExprList(Walker*, ExprList*);
+SQLITE_PRIVATE int sqlite3WalkSelect(Walker*, Select*);
+SQLITE_PRIVATE int sqlite3WalkSelectExpr(Walker*, Select*);
+SQLITE_PRIVATE int sqlite3WalkSelectFrom(Walker*, Select*);
+SQLITE_PRIVATE int sqlite3ExprWalkNoop(Walker*, Expr*);
+SQLITE_PRIVATE int sqlite3SelectWalkNoop(Walker*, Select*);
+SQLITE_PRIVATE int sqlite3SelectWalkFail(Walker*, Select*);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3SelectWalkAssert2(Walker*, Select*);
+#endif
+
+/*
+** Return code from the parse-tree walking primitives and their
+** callbacks.
+*/
+#define WRC_Continue 0 /* Continue down into children */
+#define WRC_Prune 1 /* Omit children but continue walking siblings */
+#define WRC_Abort 2 /* Abandon the tree walk */
+
+/*
+** An instance of this structure represents a set of one or more CTEs
+** (common table expressions) created by a single WITH clause.
+*/
+struct With {
+ int nCte; /* Number of CTEs in the WITH clause */
+ With *pOuter; /* Containing WITH clause, or NULL */
+ struct Cte { /* For each CTE in the WITH clause.... */
+ char *zName; /* Name of this CTE */
+ ExprList *pCols; /* List of explicit column names, or NULL */
+ Select *pSelect; /* The definition of this CTE */
+ const char *zCteErr; /* Error message for circular references */
+ } a[1];
+};
+
+#ifdef SQLITE_DEBUG
+/*
+** An instance of the TreeView object is used for printing the content of
+** data structures on sqlite3DebugPrintf() using a tree-like view.
+*/
+struct TreeView {
+ int iLevel; /* Which level of the tree we are on */
+ u8 bLine[100]; /* Draw vertical in column i if bLine[i] is true */
+};
+#endif /* SQLITE_DEBUG */
+
+/*
+** This object is used in varioius ways, all related to window functions
+**
+** (1) A single instance of this structure is attached to the
+** the Expr.pWin field for each window function in an expression tree.
+** This object holds the information contained in the OVER clause,
+** plus additional fields used during code generation.
+**
+** (2) All window functions in a single SELECT form a linked-list
+** attached to Select.pWin. The Window.pFunc and Window.pExpr
+** fields point back to the expression that is the window function.
+**
+** (3) The terms of the WINDOW clause of a SELECT are instances of this
+** object on a linked list attached to Select.pWinDefn.
+**
+** The uses (1) and (2) are really the same Window object that just happens
+** to be accessible in two different ways. Use (3) is are separate objects.
+*/
+struct Window {
+ char *zName; /* Name of window (may be NULL) */
+ ExprList *pPartition; /* PARTITION BY clause */
+ ExprList *pOrderBy; /* ORDER BY clause */
+ u8 eType; /* TK_RANGE or TK_ROWS */
+ u8 eStart; /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
+ u8 eEnd; /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
+ Expr *pStart; /* Expression for " PRECEDING" */
+ Expr *pEnd; /* Expression for " FOLLOWING" */
+ Window *pNextWin; /* Next window function belonging to this SELECT */
+ Expr *pFilter; /* The FILTER expression */
+ FuncDef *pFunc; /* The function */
+ int iEphCsr; /* Partition buffer or Peer buffer */
+ int regAccum;
+ int regResult;
+ int csrApp; /* Function cursor (used by min/max) */
+ int regApp; /* Function register (also used by min/max) */
+ int regPart; /* First in a set of registers holding PARTITION BY
+ ** and ORDER BY values for the window */
+ Expr *pOwner; /* Expression object this window is attached to */
+ int nBufferCol; /* Number of columns in buffer table */
+ int iArgCol; /* Offset of first argument for this function */
+};
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+SQLITE_PRIVATE void sqlite3WindowDelete(sqlite3*, Window*);
+SQLITE_PRIVATE void sqlite3WindowListDelete(sqlite3 *db, Window *p);
+SQLITE_PRIVATE Window *sqlite3WindowAlloc(Parse*, int, int, Expr*, int , Expr*);
+SQLITE_PRIVATE void sqlite3WindowAttach(Parse*, Expr*, Window*);
+SQLITE_PRIVATE int sqlite3WindowCompare(Parse*, Window*, Window*);
+SQLITE_PRIVATE void sqlite3WindowCodeInit(Parse*, Window*);
+SQLITE_PRIVATE void sqlite3WindowCodeStep(Parse*, Select*, WhereInfo*, int, int);
+SQLITE_PRIVATE int sqlite3WindowRewrite(Parse*, Select*);
+SQLITE_PRIVATE int sqlite3ExpandSubquery(Parse*, struct SrcList_item*);
+SQLITE_PRIVATE void sqlite3WindowUpdate(Parse*, Window*, Window*, FuncDef*);
+SQLITE_PRIVATE Window *sqlite3WindowDup(sqlite3 *db, Expr *pOwner, Window *p);
+SQLITE_PRIVATE Window *sqlite3WindowListDup(sqlite3 *db, Window *p);
+SQLITE_PRIVATE void sqlite3WindowFunctions(void);
+#else
+# define sqlite3WindowDelete(a,b)
+# define sqlite3WindowFunctions()
+# define sqlite3WindowAttach(a,b,c)
+#endif
+
+/*
+** Assuming zIn points to the first byte of a UTF-8 character,
+** advance zIn to point to the first byte of the next UTF-8 character.
+*/
+#define SQLITE_SKIP_UTF8(zIn) { \
+ if( (*(zIn++))>=0xc0 ){ \
+ while( (*zIn & 0xc0)==0x80 ){ zIn++; } \
+ } \
+}
+
+/*
+** The SQLITE_*_BKPT macros are substitutes for the error codes with
+** the same name but without the _BKPT suffix. These macros invoke
+** routines that report the line-number on which the error originated
+** using sqlite3_log(). The routines also provide a convenient place
+** to set a debugger breakpoint.
+*/
+SQLITE_PRIVATE int sqlite3ReportError(int iErr, int lineno, const char *zType);
+SQLITE_PRIVATE int sqlite3CorruptError(int);
+SQLITE_PRIVATE int sqlite3MisuseError(int);
+SQLITE_PRIVATE int sqlite3CantopenError(int);
+#define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
+#define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
+#define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3NomemError(int);
+SQLITE_PRIVATE int sqlite3IoerrnomemError(int);
+SQLITE_PRIVATE int sqlite3CorruptPgnoError(int,Pgno);
+# define SQLITE_NOMEM_BKPT sqlite3NomemError(__LINE__)
+# define SQLITE_IOERR_NOMEM_BKPT sqlite3IoerrnomemError(__LINE__)
+# define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptPgnoError(__LINE__,(P))
+#else
+# define SQLITE_NOMEM_BKPT SQLITE_NOMEM
+# define SQLITE_IOERR_NOMEM_BKPT SQLITE_IOERR_NOMEM
+# define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptError(__LINE__)
+#endif
+
+/*
+** FTS3 and FTS4 both require virtual table support
+*/
+#if defined(SQLITE_OMIT_VIRTUALTABLE)
+# undef SQLITE_ENABLE_FTS3
+# undef SQLITE_ENABLE_FTS4
+#endif
+
+/*
+** FTS4 is really an extension for FTS3. It is enabled using the
+** SQLITE_ENABLE_FTS3 macro. But to avoid confusion we also call
+** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
+*/
+#if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
+# define SQLITE_ENABLE_FTS3 1
+#endif
+
+/*
+** The ctype.h header is needed for non-ASCII systems. It is also
+** needed by FTS3 when FTS3 is included in the amalgamation.
+*/
+#if !defined(SQLITE_ASCII) || \
+ (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
+# include
+#endif
+
+/*
+** The following macros mimic the standard library functions toupper(),
+** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
+** sqlite versions only work for ASCII characters, regardless of locale.
+*/
+#ifdef SQLITE_ASCII
+# define sqlite3Toupper(x) ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
+# define sqlite3Isspace(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
+# define sqlite3Isalnum(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
+# define sqlite3Isalpha(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
+# define sqlite3Isdigit(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
+# define sqlite3Isxdigit(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
+# define sqlite3Tolower(x) (sqlite3UpperToLower[(unsigned char)(x)])
+# define sqlite3Isquote(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x80)
+#else
+# define sqlite3Toupper(x) toupper((unsigned char)(x))
+# define sqlite3Isspace(x) isspace((unsigned char)(x))
+# define sqlite3Isalnum(x) isalnum((unsigned char)(x))
+# define sqlite3Isalpha(x) isalpha((unsigned char)(x))
+# define sqlite3Isdigit(x) isdigit((unsigned char)(x))
+# define sqlite3Isxdigit(x) isxdigit((unsigned char)(x))
+# define sqlite3Tolower(x) tolower((unsigned char)(x))
+# define sqlite3Isquote(x) ((x)=='"'||(x)=='\''||(x)=='['||(x)=='`')
+#endif
+SQLITE_PRIVATE int sqlite3IsIdChar(u8);
+
+/*
+** Internal function prototypes
+*/
+SQLITE_PRIVATE int sqlite3StrICmp(const char*,const char*);
+SQLITE_PRIVATE int sqlite3Strlen30(const char*);
+SQLITE_PRIVATE char *sqlite3ColumnType(Column*,char*);
+#define sqlite3StrNICmp sqlite3_strnicmp
+
+SQLITE_PRIVATE int sqlite3MallocInit(void);
+SQLITE_PRIVATE void sqlite3MallocEnd(void);
+SQLITE_PRIVATE void *sqlite3Malloc(u64);
+SQLITE_PRIVATE void *sqlite3MallocZero(u64);
+SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3*, u64);
+SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3*, u64);
+SQLITE_PRIVATE void *sqlite3DbMallocRawNN(sqlite3*, u64);
+SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3*,const char*);
+SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3*,const char*, u64);
+SQLITE_PRIVATE char *sqlite3DbSpanDup(sqlite3*,const char*,const char*);
+SQLITE_PRIVATE void *sqlite3Realloc(void*, u64);
+SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *, void *, u64);
+SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *, void *, u64);
+SQLITE_PRIVATE void sqlite3DbFree(sqlite3*, void*);
+SQLITE_PRIVATE void sqlite3DbFreeNN(sqlite3*, void*);
+SQLITE_PRIVATE int sqlite3MallocSize(void*);
+SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3*, void*);
+SQLITE_PRIVATE void *sqlite3PageMalloc(int);
+SQLITE_PRIVATE void sqlite3PageFree(void*);
+SQLITE_PRIVATE void sqlite3MemSetDefault(void);
+#ifndef SQLITE_UNTESTABLE
+SQLITE_PRIVATE void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
+#endif
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void);
+
+/*
+** On systems with ample stack space and that support alloca(), make
+** use of alloca() to obtain space for large automatic objects. By default,
+** obtain space from malloc().
+**
+** The alloca() routine never returns NULL. This will cause code paths
+** that deal with sqlite3StackAlloc() failures to be unreachable.
+*/
+#ifdef SQLITE_USE_ALLOCA
+# define sqlite3StackAllocRaw(D,N) alloca(N)
+# define sqlite3StackAllocZero(D,N) memset(alloca(N), 0, N)
+# define sqlite3StackFree(D,P)
+#else
+# define sqlite3StackAllocRaw(D,N) sqlite3DbMallocRaw(D,N)
+# define sqlite3StackAllocZero(D,N) sqlite3DbMallocZero(D,N)
+# define sqlite3StackFree(D,P) sqlite3DbFree(D,P)
+#endif
+
+/* Do not allow both MEMSYS5 and MEMSYS3 to be defined together. If they
+** are, disable MEMSYS3
+*/
+#ifdef SQLITE_ENABLE_MEMSYS5
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
+#undef SQLITE_ENABLE_MEMSYS3
+#endif
+#ifdef SQLITE_ENABLE_MEMSYS3
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
+#endif
+
+
+#ifndef SQLITE_MUTEX_OMIT
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3NoopMutex(void);
+SQLITE_PRIVATE sqlite3_mutex *sqlite3MutexAlloc(int);
+SQLITE_PRIVATE int sqlite3MutexInit(void);
+SQLITE_PRIVATE int sqlite3MutexEnd(void);
+#endif
+#if !defined(SQLITE_MUTEX_OMIT) && !defined(SQLITE_MUTEX_NOOP)
+SQLITE_PRIVATE void sqlite3MemoryBarrier(void);
+#else
+# define sqlite3MemoryBarrier()
+#endif
+
+SQLITE_PRIVATE sqlite3_int64 sqlite3StatusValue(int);
+SQLITE_PRIVATE void sqlite3StatusUp(int, int);
+SQLITE_PRIVATE void sqlite3StatusDown(int, int);
+SQLITE_PRIVATE void sqlite3StatusHighwater(int, int);
+SQLITE_PRIVATE int sqlite3LookasideUsed(sqlite3*,int*);
+
+/* Access to mutexes used by sqlite3_status() */
+SQLITE_PRIVATE sqlite3_mutex *sqlite3Pcache1Mutex(void);
+SQLITE_PRIVATE sqlite3_mutex *sqlite3MallocMutex(void);
+
+#if defined(SQLITE_ENABLE_MULTITHREADED_CHECKS) && !defined(SQLITE_MUTEX_OMIT)
+SQLITE_PRIVATE void sqlite3MutexWarnOnContention(sqlite3_mutex*);
+#else
+# define sqlite3MutexWarnOnContention(x)
+#endif
+
+#ifndef SQLITE_OMIT_FLOATING_POINT
+SQLITE_PRIVATE int sqlite3IsNaN(double);
+#else
+# define sqlite3IsNaN(X) 0
+#endif
+
+/*
+** An instance of the following structure holds information about SQL
+** functions arguments that are the parameters to the printf() function.
+*/
+struct PrintfArguments {
+ int nArg; /* Total number of arguments */
+ int nUsed; /* Number of arguments used so far */
+ sqlite3_value **apArg; /* The argument values */
+};
+
+SQLITE_PRIVATE char *sqlite3MPrintf(sqlite3*,const char*, ...);
+SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
+#if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
+SQLITE_PRIVATE void sqlite3DebugPrintf(const char*, ...);
+#endif
+#if defined(SQLITE_TEST)
+SQLITE_PRIVATE void *sqlite3TestTextToPtr(const char*);
+#endif
+
+#if defined(SQLITE_DEBUG)
+SQLITE_PRIVATE void sqlite3TreeViewExpr(TreeView*, const Expr*, u8);
+SQLITE_PRIVATE void sqlite3TreeViewBareExprList(TreeView*, const ExprList*, const char*);
+SQLITE_PRIVATE void sqlite3TreeViewExprList(TreeView*, const ExprList*, u8, const char*);
+SQLITE_PRIVATE void sqlite3TreeViewSelect(TreeView*, const Select*, u8);
+SQLITE_PRIVATE void sqlite3TreeViewWith(TreeView*, const With*, u8);
+#ifndef SQLITE_OMIT_WINDOWFUNC
+SQLITE_PRIVATE void sqlite3TreeViewWindow(TreeView*, const Window*, u8);
+SQLITE_PRIVATE void sqlite3TreeViewWinFunc(TreeView*, const Window*, u8);
+#endif
+#endif
+
+
+SQLITE_PRIVATE void sqlite3SetString(char **, sqlite3*, const char*);
+SQLITE_PRIVATE void sqlite3ErrorMsg(Parse*, const char*, ...);
+SQLITE_PRIVATE void sqlite3Dequote(char*);
+SQLITE_PRIVATE void sqlite3TokenInit(Token*,char*);
+SQLITE_PRIVATE int sqlite3KeywordCode(const unsigned char*, int);
+SQLITE_PRIVATE int sqlite3RunParser(Parse*, const char*, char **);
+SQLITE_PRIVATE void sqlite3FinishCoding(Parse*);
+SQLITE_PRIVATE int sqlite3GetTempReg(Parse*);
+SQLITE_PRIVATE void sqlite3ReleaseTempReg(Parse*,int);
+SQLITE_PRIVATE int sqlite3GetTempRange(Parse*,int);
+SQLITE_PRIVATE void sqlite3ReleaseTempRange(Parse*,int,int);
+SQLITE_PRIVATE void sqlite3ClearTempRegCache(Parse*);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3NoTempsInRange(Parse*,int,int);
+#endif
+SQLITE_PRIVATE Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
+SQLITE_PRIVATE Expr *sqlite3Expr(sqlite3*,int,const char*);
+SQLITE_PRIVATE void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
+SQLITE_PRIVATE Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*);
+SQLITE_PRIVATE void sqlite3PExprAddSelect(Parse*, Expr*, Select*);
+SQLITE_PRIVATE Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
+SQLITE_PRIVATE Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*, int);
+SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse*, Expr*, u32);
+SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3*, Expr*);
+SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
+SQLITE_PRIVATE ExprList *sqlite3ExprListAppendVector(Parse*,ExprList*,IdList*,Expr*);
+SQLITE_PRIVATE void sqlite3ExprListSetSortOrder(ExprList*,int);
+SQLITE_PRIVATE void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
+SQLITE_PRIVATE void sqlite3ExprListSetSpan(Parse*,ExprList*,const char*,const char*);
+SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3*, ExprList*);
+SQLITE_PRIVATE u32 sqlite3ExprListFlags(const ExprList*);
+SQLITE_PRIVATE int sqlite3Init(sqlite3*, char**);
+SQLITE_PRIVATE int sqlite3InitCallback(void*, int, char**, char**);
+SQLITE_PRIVATE int sqlite3InitOne(sqlite3*, int, char**, u32);
+SQLITE_PRIVATE void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+SQLITE_PRIVATE Module *sqlite3PragmaVtabRegister(sqlite3*,const char *zName);
+#endif
+SQLITE_PRIVATE void sqlite3ResetAllSchemasOfConnection(sqlite3*);
+SQLITE_PRIVATE void sqlite3ResetOneSchema(sqlite3*,int);
+SQLITE_PRIVATE void sqlite3CollapseDatabaseArray(sqlite3*);
+SQLITE_PRIVATE void sqlite3CommitInternalChanges(sqlite3*);
+SQLITE_PRIVATE void sqlite3DeleteColumnNames(sqlite3*,Table*);
+SQLITE_PRIVATE int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
+SQLITE_PRIVATE void sqlite3SelectAddColumnTypeAndCollation(Parse*,Table*,Select*);
+SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse*,Select*);
+SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *, int);
+SQLITE_PRIVATE Index *sqlite3PrimaryKeyIndex(Table*);
+SQLITE_PRIVATE i16 sqlite3ColumnOfIndex(Index*, i16);
+SQLITE_PRIVATE void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
+#if SQLITE_ENABLE_HIDDEN_COLUMNS
+SQLITE_PRIVATE void sqlite3ColumnPropertiesFromName(Table*, Column*);
+#else
+# define sqlite3ColumnPropertiesFromName(T,C) /* no-op */
+#endif
+SQLITE_PRIVATE void sqlite3AddColumn(Parse*,Token*,Token*);
+SQLITE_PRIVATE void sqlite3AddNotNull(Parse*, int);
+SQLITE_PRIVATE void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
+SQLITE_PRIVATE void sqlite3AddCheckConstraint(Parse*, Expr*);
+SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse*,Expr*,const char*,const char*);
+SQLITE_PRIVATE void sqlite3AddCollateType(Parse*, Token*);
+SQLITE_PRIVATE void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
+SQLITE_PRIVATE int sqlite3ParseUri(const char*,const char*,unsigned int*,
+ sqlite3_vfs**,char**,char **);
+SQLITE_PRIVATE Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
+
+#ifdef SQLITE_UNTESTABLE
+# define sqlite3FaultSim(X) SQLITE_OK
+#else
+SQLITE_PRIVATE int sqlite3FaultSim(int);
+#endif
+
+SQLITE_PRIVATE Bitvec *sqlite3BitvecCreate(u32);
+SQLITE_PRIVATE int sqlite3BitvecTest(Bitvec*, u32);
+SQLITE_PRIVATE int sqlite3BitvecTestNotNull(Bitvec*, u32);
+SQLITE_PRIVATE int sqlite3BitvecSet(Bitvec*, u32);
+SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec*, u32, void*);
+SQLITE_PRIVATE void sqlite3BitvecDestroy(Bitvec*);
+SQLITE_PRIVATE u32 sqlite3BitvecSize(Bitvec*);
+#ifndef SQLITE_UNTESTABLE
+SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int,int*);
+#endif
+
+SQLITE_PRIVATE RowSet *sqlite3RowSetInit(sqlite3*);
+SQLITE_PRIVATE void sqlite3RowSetDelete(void*);
+SQLITE_PRIVATE void sqlite3RowSetClear(void*);
+SQLITE_PRIVATE void sqlite3RowSetInsert(RowSet*, i64);
+SQLITE_PRIVATE int sqlite3RowSetTest(RowSet*, int iBatch, i64);
+SQLITE_PRIVATE int sqlite3RowSetNext(RowSet*, i64*);
+
+SQLITE_PRIVATE void sqlite3CreateView(Parse*,Token*,Token*,Token*,ExprList*,Select*,int,int);
+
+#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
+SQLITE_PRIVATE int sqlite3ViewGetColumnNames(Parse*,Table*);
+#else
+# define sqlite3ViewGetColumnNames(A,B) 0
+#endif
+
+#if SQLITE_MAX_ATTACHED>30
+SQLITE_PRIVATE int sqlite3DbMaskAllZero(yDbMask);
+#endif
+SQLITE_PRIVATE void sqlite3DropTable(Parse*, SrcList*, int, int);
+SQLITE_PRIVATE void sqlite3CodeDropTable(Parse*, Table*, int, int);
+SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3*, Table*);
+SQLITE_PRIVATE void sqlite3FreeIndex(sqlite3*, Index*);
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+SQLITE_PRIVATE void sqlite3AutoincrementBegin(Parse *pParse);
+SQLITE_PRIVATE void sqlite3AutoincrementEnd(Parse *pParse);
+#else
+# define sqlite3AutoincrementBegin(X)
+# define sqlite3AutoincrementEnd(X)
+#endif
+SQLITE_PRIVATE void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int, Upsert*);
+SQLITE_PRIVATE void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
+SQLITE_PRIVATE IdList *sqlite3IdListAppend(Parse*, IdList*, Token*);
+SQLITE_PRIVATE int sqlite3IdListIndex(IdList*,const char*);
+SQLITE_PRIVATE SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
+SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
+SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
+ Token*, Select*, Expr*, IdList*);
+SQLITE_PRIVATE void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
+SQLITE_PRIVATE void sqlite3SrcListFuncArgs(Parse*, SrcList*, ExprList*);
+SQLITE_PRIVATE int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
+SQLITE_PRIVATE void sqlite3SrcListShiftJoinType(SrcList*);
+SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse*, SrcList*);
+SQLITE_PRIVATE void sqlite3IdListDelete(sqlite3*, IdList*);
+SQLITE_PRIVATE void sqlite3SrcListDelete(sqlite3*, SrcList*);
+SQLITE_PRIVATE Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
+SQLITE_PRIVATE void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
+ Expr*, int, int, u8);
+SQLITE_PRIVATE void sqlite3DropIndex(Parse*, SrcList*, int);
+SQLITE_PRIVATE int sqlite3Select(Parse*, Select*, SelectDest*);
+SQLITE_PRIVATE Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
+ Expr*,ExprList*,u32,Expr*);
+SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3*, Select*);
+SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse*, SrcList*);
+SQLITE_PRIVATE int sqlite3IsReadOnly(Parse*, Table*, int);
+SQLITE_PRIVATE void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
+#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
+SQLITE_PRIVATE Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,char*);
+#endif
+SQLITE_PRIVATE void sqlite3DeleteFrom(Parse*, SrcList*, Expr*, ExprList*, Expr*);
+SQLITE_PRIVATE void sqlite3Update(Parse*, SrcList*, ExprList*,Expr*,int,ExprList*,Expr*,
+ Upsert*);
+SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
+SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo*);
+SQLITE_PRIVATE LogEst sqlite3WhereOutputRowCount(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereIsDistinct(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereIsOrdered(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereOrderByLimitOptLabel(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereIsSorted(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereContinueLabel(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereBreakLabel(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereOkOnePass(WhereInfo*, int*);
+#define ONEPASS_OFF 0 /* Use of ONEPASS not allowed */
+#define ONEPASS_SINGLE 1 /* ONEPASS valid for a single row update */
+#define ONEPASS_MULTI 2 /* ONEPASS is valid for multiple rows */
+SQLITE_PRIVATE void sqlite3ExprCodeLoadIndexColumn(Parse*, Index*, int, int, int);
+SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
+SQLITE_PRIVATE void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
+SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse*, int, int, int);
+SQLITE_PRIVATE void sqlite3ExprCode(Parse*, Expr*, int);
+SQLITE_PRIVATE void sqlite3ExprCodeCopy(Parse*, Expr*, int);
+SQLITE_PRIVATE void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprCodeAtInit(Parse*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
+SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse*, Expr*, int);
+SQLITE_PRIVATE void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int, u8);
+#define SQLITE_ECEL_DUP 0x01 /* Deep, not shallow copies */
+#define SQLITE_ECEL_FACTOR 0x02 /* Factor out constant terms */
+#define SQLITE_ECEL_REF 0x04 /* Use ExprList.u.x.iOrderByCol */
+#define SQLITE_ECEL_OMITREF 0x08 /* Omit if ExprList.u.x.iOrderByCol */
+SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
+SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
+SQLITE_PRIVATE void sqlite3ExprIfFalseDup(Parse*, Expr*, int, int);
+SQLITE_PRIVATE Table *sqlite3FindTable(sqlite3*,const char*, const char*);
+#define LOCATE_VIEW 0x01
+#define LOCATE_NOERR 0x02
+SQLITE_PRIVATE Table *sqlite3LocateTable(Parse*,u32 flags,const char*, const char*);
+SQLITE_PRIVATE Table *sqlite3LocateTableItem(Parse*,u32 flags,struct SrcList_item *);
+SQLITE_PRIVATE Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
+SQLITE_PRIVATE void sqlite3Vacuum(Parse*,Token*);
+SQLITE_PRIVATE int sqlite3RunVacuum(char**, sqlite3*, int);
+SQLITE_PRIVATE char *sqlite3NameFromToken(sqlite3*, Token*);
+SQLITE_PRIVATE int sqlite3ExprCompare(Parse*,Expr*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprCompareSkip(Expr*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprListCompare(ExprList*, ExprList*, int);
+SQLITE_PRIVATE int sqlite3ExprImpliesExpr(Parse*,Expr*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprImpliesNonNullRow(Expr*,int);
+SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
+SQLITE_PRIVATE void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
+SQLITE_PRIVATE int sqlite3ExprCoveredByIndex(Expr*, int iCur, Index *pIdx);
+SQLITE_PRIVATE int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
+SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse*);
+#ifndef SQLITE_UNTESTABLE
+SQLITE_PRIVATE void sqlite3PrngSaveState(void);
+SQLITE_PRIVATE void sqlite3PrngRestoreState(void);
+#endif
+SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3*,int);
+SQLITE_PRIVATE void sqlite3CodeVerifySchema(Parse*, int);
+SQLITE_PRIVATE void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
+SQLITE_PRIVATE void sqlite3BeginTransaction(Parse*, int);
+SQLITE_PRIVATE void sqlite3EndTransaction(Parse*,int);
+SQLITE_PRIVATE void sqlite3Savepoint(Parse*, int, Token*);
+SQLITE_PRIVATE void sqlite3CloseSavepoints(sqlite3 *);
+SQLITE_PRIVATE void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
+SQLITE_PRIVATE int sqlite3ExprIdToTrueFalse(Expr*);
+SQLITE_PRIVATE int sqlite3ExprTruthValue(const Expr*);
+SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr*);
+SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr*);
+SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr*, u8);
+SQLITE_PRIVATE int sqlite3ExprIsConstantOrGroupBy(Parse*, Expr*, ExprList*);
+SQLITE_PRIVATE int sqlite3ExprIsTableConstant(Expr*,int);
+#ifdef SQLITE_ENABLE_CURSOR_HINTS
+SQLITE_PRIVATE int sqlite3ExprContainsSubquery(Expr*);
+#endif
+SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr*, int*);
+SQLITE_PRIVATE int sqlite3ExprCanBeNull(const Expr*);
+SQLITE_PRIVATE int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
+SQLITE_PRIVATE int sqlite3IsRowid(const char*);
+SQLITE_PRIVATE void sqlite3GenerateRowDelete(
+ Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8,int);
+SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*, int);
+SQLITE_PRIVATE int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
+SQLITE_PRIVATE void sqlite3ResolvePartIdxLabel(Parse*,int);
+SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
+ u8,u8,int,int*,int*,Upsert*);
+#ifdef SQLITE_ENABLE_NULL_TRIM
+SQLITE_PRIVATE void sqlite3SetMakeRecordP5(Vdbe*,Table*);
+#else
+# define sqlite3SetMakeRecordP5(A,B)
+#endif
+SQLITE_PRIVATE void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
+SQLITE_PRIVATE int sqlite3OpenTableAndIndices(Parse*, Table*, int, u8, int, u8*, int*, int*);
+SQLITE_PRIVATE void sqlite3BeginWriteOperation(Parse*, int, int);
+SQLITE_PRIVATE void sqlite3MultiWrite(Parse*);
+SQLITE_PRIVATE void sqlite3MayAbort(Parse*);
+SQLITE_PRIVATE void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
+SQLITE_PRIVATE void sqlite3UniqueConstraint(Parse*, int, Index*);
+SQLITE_PRIVATE void sqlite3RowidConstraint(Parse*, int, Table*);
+SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
+SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
+SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
+SQLITE_PRIVATE IdList *sqlite3IdListDup(sqlite3*,IdList*);
+SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3*,Select*,int);
+SQLITE_PRIVATE void sqlite3InsertBuiltinFuncs(FuncDef*,int);
+SQLITE_PRIVATE FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,u8,u8);
+SQLITE_PRIVATE void sqlite3RegisterBuiltinFunctions(void);
+SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(void);
+SQLITE_PRIVATE void sqlite3RegisterPerConnectionBuiltinFunctions(sqlite3*);
+SQLITE_PRIVATE int sqlite3SafetyCheckOk(sqlite3*);
+SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3*);
+SQLITE_PRIVATE void sqlite3ChangeCookie(Parse*, int);
+
+#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
+SQLITE_PRIVATE void sqlite3MaterializeView(Parse*, Table*, Expr*, ExprList*,Expr*,int);
+#endif
+
+#ifndef SQLITE_OMIT_TRIGGER
+SQLITE_PRIVATE void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
+ Expr*,int, int);
+SQLITE_PRIVATE void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
+SQLITE_PRIVATE void sqlite3DropTrigger(Parse*, SrcList*, int);
+SQLITE_PRIVATE void sqlite3DropTriggerPtr(Parse*, Trigger*);
+SQLITE_PRIVATE Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
+SQLITE_PRIVATE Trigger *sqlite3TriggerList(Parse *, Table *);
+SQLITE_PRIVATE void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
+ int, int, int);
+SQLITE_PRIVATE void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
+ void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
+SQLITE_PRIVATE void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*,
+ const char*,const char*);
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerInsertStep(Parse*,Token*, IdList*,
+ Select*,u8,Upsert*,
+ const char*,const char*);
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerUpdateStep(Parse*,Token*,ExprList*, Expr*, u8,
+ const char*,const char*);
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerDeleteStep(Parse*,Token*, Expr*,
+ const char*,const char*);
+SQLITE_PRIVATE void sqlite3DeleteTrigger(sqlite3*, Trigger*);
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
+SQLITE_PRIVATE u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
+# define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
+# define sqlite3IsToplevel(p) ((p)->pToplevel==0)
+#else
+# define sqlite3TriggersExist(B,C,D,E,F) 0
+# define sqlite3DeleteTrigger(A,B)
+# define sqlite3DropTriggerPtr(A,B)
+# define sqlite3UnlinkAndDeleteTrigger(A,B,C)
+# define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
+# define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
+# define sqlite3TriggerList(X, Y) 0
+# define sqlite3ParseToplevel(p) p
+# define sqlite3IsToplevel(p) 1
+# define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
+#endif
+
+SQLITE_PRIVATE int sqlite3JoinType(Parse*, Token*, Token*, Token*);
+SQLITE_PRIVATE void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
+SQLITE_PRIVATE void sqlite3DeferForeignKey(Parse*, int);
+#ifndef SQLITE_OMIT_AUTHORIZATION
+SQLITE_PRIVATE void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
+SQLITE_PRIVATE int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
+SQLITE_PRIVATE void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
+SQLITE_PRIVATE void sqlite3AuthContextPop(AuthContext*);
+SQLITE_PRIVATE int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
+#else
+# define sqlite3AuthRead(a,b,c,d)
+# define sqlite3AuthCheck(a,b,c,d,e) SQLITE_OK
+# define sqlite3AuthContextPush(a,b,c)
+# define sqlite3AuthContextPop(a) ((void)(a))
+#endif
+SQLITE_PRIVATE void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
+SQLITE_PRIVATE void sqlite3Detach(Parse*, Expr*);
+SQLITE_PRIVATE void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
+SQLITE_PRIVATE int sqlite3FixSrcList(DbFixer*, SrcList*);
+SQLITE_PRIVATE int sqlite3FixSelect(DbFixer*, Select*);
+SQLITE_PRIVATE int sqlite3FixExpr(DbFixer*, Expr*);
+SQLITE_PRIVATE int sqlite3FixExprList(DbFixer*, ExprList*);
+SQLITE_PRIVATE int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
+SQLITE_PRIVATE int sqlite3AtoF(const char *z, double*, int, u8);
+SQLITE_PRIVATE int sqlite3GetInt32(const char *, int*);
+SQLITE_PRIVATE int sqlite3Atoi(const char*);
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *pData, int nChar);
+#endif
+SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *pData, int nByte);
+SQLITE_PRIVATE u32 sqlite3Utf8Read(const u8**);
+SQLITE_PRIVATE LogEst sqlite3LogEst(u64);
+SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst,LogEst);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double);
+#endif
+#if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \
+ defined(SQLITE_ENABLE_STAT3_OR_STAT4) || \
+ defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
+SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst);
+#endif
+SQLITE_PRIVATE VList *sqlite3VListAdd(sqlite3*,VList*,const char*,int,int);
+SQLITE_PRIVATE const char *sqlite3VListNumToName(VList*,int);
+SQLITE_PRIVATE int sqlite3VListNameToNum(VList*,const char*,int);
+
+/*
+** Routines to read and write variable-length integers. These used to
+** be defined locally, but now we use the varint routines in the util.c
+** file.
+*/
+SQLITE_PRIVATE int sqlite3PutVarint(unsigned char*, u64);
+SQLITE_PRIVATE u8 sqlite3GetVarint(const unsigned char *, u64 *);
+SQLITE_PRIVATE u8 sqlite3GetVarint32(const unsigned char *, u32 *);
+SQLITE_PRIVATE int sqlite3VarintLen(u64 v);
+
+/*
+** The common case is for a varint to be a single byte. They following
+** macros handle the common case without a procedure call, but then call
+** the procedure for larger varints.
+*/
+#define getVarint32(A,B) \
+ (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
+#define putVarint32(A,B) \
+ (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
+ sqlite3PutVarint((A),(B)))
+#define getVarint sqlite3GetVarint
+#define putVarint sqlite3PutVarint
+
+
+SQLITE_PRIVATE const char *sqlite3IndexAffinityStr(sqlite3*, Index*);
+SQLITE_PRIVATE void sqlite3TableAffinity(Vdbe*, Table*, int);
+SQLITE_PRIVATE char sqlite3CompareAffinity(Expr *pExpr, char aff2);
+SQLITE_PRIVATE int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
+SQLITE_PRIVATE char sqlite3TableColumnAffinity(Table*,int);
+SQLITE_PRIVATE char sqlite3ExprAffinity(Expr *pExpr);
+SQLITE_PRIVATE int sqlite3Atoi64(const char*, i64*, int, u8);
+SQLITE_PRIVATE int sqlite3DecOrHexToI64(const char*, i64*);
+SQLITE_PRIVATE void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
+SQLITE_PRIVATE void sqlite3Error(sqlite3*,int);
+SQLITE_PRIVATE void sqlite3SystemError(sqlite3*,int);
+SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
+SQLITE_PRIVATE u8 sqlite3HexToInt(int h);
+SQLITE_PRIVATE int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
+
+#if defined(SQLITE_NEED_ERR_NAME)
+SQLITE_PRIVATE const char *sqlite3ErrName(int);
+#endif
+
+#ifdef SQLITE_ENABLE_DESERIALIZE
+SQLITE_PRIVATE int sqlite3MemdbInit(void);
+#endif
+
+SQLITE_PRIVATE const char *sqlite3ErrStr(int);
+SQLITE_PRIVATE int sqlite3ReadSchema(Parse *pParse);
+SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
+SQLITE_PRIVATE int sqlite3IsBinary(const CollSeq*);
+SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
+SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
+SQLITE_PRIVATE CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, Expr *pExpr);
+SQLITE_PRIVATE int sqlite3ExprCollSeqMatch(Parse*,Expr*,Expr*);
+SQLITE_PRIVATE Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*, int);
+SQLITE_PRIVATE Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
+SQLITE_PRIVATE Expr *sqlite3ExprSkipCollate(Expr*);
+SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *, CollSeq *);
+SQLITE_PRIVATE int sqlite3CheckObjectName(Parse *, const char *);
+SQLITE_PRIVATE void sqlite3VdbeSetChanges(sqlite3 *, int);
+SQLITE_PRIVATE int sqlite3AddInt64(i64*,i64);
+SQLITE_PRIVATE int sqlite3SubInt64(i64*,i64);
+SQLITE_PRIVATE int sqlite3MulInt64(i64*,i64);
+SQLITE_PRIVATE int sqlite3AbsInt32(int);
+#ifdef SQLITE_ENABLE_8_3_NAMES
+SQLITE_PRIVATE void sqlite3FileSuffix3(const char*, char*);
+#else
+# define sqlite3FileSuffix3(X,Y)
+#endif
+SQLITE_PRIVATE u8 sqlite3GetBoolean(const char *z,u8);
+
+SQLITE_PRIVATE const void *sqlite3ValueText(sqlite3_value*, u8);
+SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value*, u8);
+SQLITE_PRIVATE void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
+ void(*)(void*));
+SQLITE_PRIVATE void sqlite3ValueSetNull(sqlite3_value*);
+SQLITE_PRIVATE void sqlite3ValueFree(sqlite3_value*);
+SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *);
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
+#endif
+SQLITE_PRIVATE int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
+SQLITE_PRIVATE void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
+#ifndef SQLITE_AMALGAMATION
+SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[];
+SQLITE_PRIVATE const char sqlite3StrBINARY[];
+SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
+SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
+SQLITE_PRIVATE const Token sqlite3IntTokens[];
+SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config;
+SQLITE_PRIVATE FuncDefHash sqlite3BuiltinFunctions;
+#ifndef SQLITE_OMIT_WSD
+SQLITE_PRIVATE int sqlite3PendingByte;
+#endif
+#endif
+#ifdef VDBE_PROFILE
+SQLITE_PRIVATE sqlite3_uint64 sqlite3NProfileCnt;
+#endif
+SQLITE_PRIVATE void sqlite3RootPageMoved(sqlite3*, int, int, int);
+SQLITE_PRIVATE void sqlite3Reindex(Parse*, Token*, Token*);
+SQLITE_PRIVATE void sqlite3AlterFunctions(void);
+SQLITE_PRIVATE void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
+SQLITE_PRIVATE void sqlite3AlterRenameColumn(Parse*, SrcList*, Token*, Token*);
+SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *, int *);
+SQLITE_PRIVATE void sqlite3NestedParse(Parse*, const char*, ...);
+SQLITE_PRIVATE void sqlite3ExpirePreparedStatements(sqlite3*, int);
+SQLITE_PRIVATE int sqlite3CodeSubselect(Parse*, Expr *, int, int);
+SQLITE_PRIVATE void sqlite3SelectPrep(Parse*, Select*, NameContext*);
+SQLITE_PRIVATE void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
+SQLITE_PRIVATE int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
+SQLITE_PRIVATE int sqlite3ResolveExprNames(NameContext*, Expr*);
+SQLITE_PRIVATE int sqlite3ResolveExprListNames(NameContext*, ExprList*);
+SQLITE_PRIVATE void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
+SQLITE_PRIVATE void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
+SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
+SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
+SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *, Token *);
+SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
+SQLITE_PRIVATE void *sqlite3RenameTokenMap(Parse*, void*, Token*);
+SQLITE_PRIVATE void sqlite3RenameTokenRemap(Parse*, void *pTo, void *pFrom);
+SQLITE_PRIVATE void sqlite3RenameExprUnmap(Parse*, Expr*);
+SQLITE_PRIVATE void sqlite3RenameExprlistUnmap(Parse*, ExprList*);
+SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
+SQLITE_PRIVATE char sqlite3AffinityType(const char*, Column*);
+SQLITE_PRIVATE void sqlite3Analyze(Parse*, Token*, Token*);
+SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler*, sqlite3_file*);
+SQLITE_PRIVATE int sqlite3FindDb(sqlite3*, Token*);
+SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *, const char *);
+SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3*,int iDB);
+SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3*,Index*);
+SQLITE_PRIVATE void sqlite3DefaultRowEst(Index*);
+SQLITE_PRIVATE void sqlite3RegisterLikeFunctions(sqlite3*, int);
+SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
+SQLITE_PRIVATE void sqlite3SchemaClear(void *);
+SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
+SQLITE_PRIVATE int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
+SQLITE_PRIVATE void sqlite3KeyInfoUnref(KeyInfo*);
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoFromExprList(Parse*, ExprList*, int, int);
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3KeyInfoIsWriteable(KeyInfo*);
+#endif
+SQLITE_PRIVATE int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
+ void (*)(sqlite3_context*,int,sqlite3_value **),
+ void (*)(sqlite3_context*,int,sqlite3_value **),
+ void (*)(sqlite3_context*),
+ void (*)(sqlite3_context*),
+ void (*)(sqlite3_context*,int,sqlite3_value **),
+ FuncDestructor *pDestructor
+);
+SQLITE_PRIVATE void sqlite3NoopDestructor(void*);
+SQLITE_PRIVATE void sqlite3OomFault(sqlite3*);
+SQLITE_PRIVATE void sqlite3OomClear(sqlite3*);
+SQLITE_PRIVATE int sqlite3ApiExit(sqlite3 *db, int);
+SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *);
+
+SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum*, sqlite3*, char*, int, int);
+SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum*);
+SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest*,int,int);
+SQLITE_PRIVATE Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
+
+SQLITE_PRIVATE void sqlite3BackupRestart(sqlite3_backup *);
+SQLITE_PRIVATE void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
+
+#ifndef SQLITE_OMIT_SUBQUERY
+SQLITE_PRIVATE int sqlite3ExprCheckIN(Parse*, Expr*);
+#else
+# define sqlite3ExprCheckIN(x,y) SQLITE_OK
+#endif
+
+#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
+SQLITE_PRIVATE void sqlite3AnalyzeFunctions(void);
+SQLITE_PRIVATE int sqlite3Stat4ProbeSetValue(
+ Parse*,Index*,UnpackedRecord**,Expr*,int,int,int*);
+SQLITE_PRIVATE int sqlite3Stat4ValueFromExpr(Parse*, Expr*, u8, sqlite3_value**);
+SQLITE_PRIVATE void sqlite3Stat4ProbeFree(UnpackedRecord*);
+SQLITE_PRIVATE int sqlite3Stat4Column(sqlite3*, const void*, int, int, sqlite3_value**);
+SQLITE_PRIVATE char sqlite3IndexColumnAffinity(sqlite3*, Index*, int);
+#endif
+
+/*
+** The interface to the LEMON-generated parser
+*/
+#ifndef SQLITE_AMALGAMATION
+SQLITE_PRIVATE void *sqlite3ParserAlloc(void*(*)(u64), Parse*);
+SQLITE_PRIVATE void sqlite3ParserFree(void*, void(*)(void*));
+#endif
+SQLITE_PRIVATE void sqlite3Parser(void*, int, Token);
+SQLITE_PRIVATE int sqlite3ParserFallback(int);
+#ifdef YYTRACKMAXSTACKDEPTH
+SQLITE_PRIVATE int sqlite3ParserStackPeak(void*);
+#endif
+
+SQLITE_PRIVATE void sqlite3AutoLoadExtensions(sqlite3*);
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+SQLITE_PRIVATE void sqlite3CloseExtensions(sqlite3*);
+#else
+# define sqlite3CloseExtensions(X)
+#endif
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE void sqlite3TableLock(Parse *, int, int, u8, const char *);
+#else
+ #define sqlite3TableLock(v,w,x,y,z)
+#endif
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int sqlite3Utf8To8(unsigned char*);
+#endif
+
+#ifdef SQLITE_OMIT_VIRTUALTABLE
+# define sqlite3VtabClear(Y)
+# define sqlite3VtabSync(X,Y) SQLITE_OK
+# define sqlite3VtabRollback(X)
+# define sqlite3VtabCommit(X)
+# define sqlite3VtabInSync(db) 0
+# define sqlite3VtabLock(X)
+# define sqlite3VtabUnlock(X)
+# define sqlite3VtabUnlockList(X)
+# define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
+# define sqlite3GetVTable(X,Y) ((VTable*)0)
+#else
+SQLITE_PRIVATE void sqlite3VtabClear(sqlite3 *db, Table*);
+SQLITE_PRIVATE void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
+SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, Vdbe*);
+SQLITE_PRIVATE int sqlite3VtabRollback(sqlite3 *db);
+SQLITE_PRIVATE int sqlite3VtabCommit(sqlite3 *db);
+SQLITE_PRIVATE void sqlite3VtabLock(VTable *);
+SQLITE_PRIVATE void sqlite3VtabUnlock(VTable *);
+SQLITE_PRIVATE void sqlite3VtabUnlockList(sqlite3*);
+SQLITE_PRIVATE int sqlite3VtabSavepoint(sqlite3 *, int, int);
+SQLITE_PRIVATE void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
+SQLITE_PRIVATE VTable *sqlite3GetVTable(sqlite3*, Table*);
+SQLITE_PRIVATE Module *sqlite3VtabCreateModule(
+ sqlite3*,
+ const char*,
+ const sqlite3_module*,
+ void*,
+ void(*)(void*)
+ );
+# define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
+#endif
+SQLITE_PRIVATE int sqlite3VtabEponymousTableInit(Parse*,Module*);
+SQLITE_PRIVATE void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
+SQLITE_PRIVATE void sqlite3VtabMakeWritable(Parse*,Table*);
+SQLITE_PRIVATE void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
+SQLITE_PRIVATE void sqlite3VtabFinishParse(Parse*, Token*);
+SQLITE_PRIVATE void sqlite3VtabArgInit(Parse*);
+SQLITE_PRIVATE void sqlite3VtabArgExtend(Parse*, Token*);
+SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
+SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse*, Table*);
+SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
+SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *, VTable *);
+SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
+SQLITE_PRIVATE sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
+SQLITE_PRIVATE int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
+SQLITE_PRIVATE int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
+SQLITE_PRIVATE void sqlite3ParserReset(Parse*);
+SQLITE_PRIVATE int sqlite3Reprepare(Vdbe*);
+SQLITE_PRIVATE void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
+SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
+SQLITE_PRIVATE int sqlite3TempInMemory(const sqlite3*);
+SQLITE_PRIVATE const char *sqlite3JournalModename(int);
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
+SQLITE_PRIVATE int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
+#endif
+#ifndef SQLITE_OMIT_CTE
+SQLITE_PRIVATE With *sqlite3WithAdd(Parse*,With*,Token*,ExprList*,Select*);
+SQLITE_PRIVATE void sqlite3WithDelete(sqlite3*,With*);
+SQLITE_PRIVATE void sqlite3WithPush(Parse*, With*, u8);
+#else
+#define sqlite3WithPush(x,y,z)
+#define sqlite3WithDelete(x,y)
+#endif
+#ifndef SQLITE_OMIT_UPSERT
+SQLITE_PRIVATE Upsert *sqlite3UpsertNew(sqlite3*,ExprList*,Expr*,ExprList*,Expr*);
+SQLITE_PRIVATE void sqlite3UpsertDelete(sqlite3*,Upsert*);
+SQLITE_PRIVATE Upsert *sqlite3UpsertDup(sqlite3*,Upsert*);
+SQLITE_PRIVATE int sqlite3UpsertAnalyzeTarget(Parse*,SrcList*,Upsert*);
+SQLITE_PRIVATE void sqlite3UpsertDoUpdate(Parse*,Upsert*,Table*,Index*,int);
+#else
+#define sqlite3UpsertNew(v,w,x,y,z) ((Upsert*)0)
+#define sqlite3UpsertDelete(x,y)
+#define sqlite3UpsertDup(x,y) ((Upsert*)0)
+#endif
+
+
+/* Declarations for functions in fkey.c. All of these are replaced by
+** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
+** key functionality is available. If OMIT_TRIGGER is defined but
+** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
+** this case foreign keys are parsed, but no other functionality is
+** provided (enforcement of FK constraints requires the triggers sub-system).
+*/
+#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
+SQLITE_PRIVATE void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
+SQLITE_PRIVATE void sqlite3FkDropTable(Parse*, SrcList *, Table*);
+SQLITE_PRIVATE void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
+SQLITE_PRIVATE int sqlite3FkRequired(Parse*, Table*, int*, int);
+SQLITE_PRIVATE u32 sqlite3FkOldmask(Parse*, Table*);
+SQLITE_PRIVATE FKey *sqlite3FkReferences(Table *);
+#else
+ #define sqlite3FkActions(a,b,c,d,e,f)
+ #define sqlite3FkCheck(a,b,c,d,e,f)
+ #define sqlite3FkDropTable(a,b,c)
+ #define sqlite3FkOldmask(a,b) 0
+ #define sqlite3FkRequired(a,b,c,d) 0
+ #define sqlite3FkReferences(a) 0
+#endif
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE void sqlite3FkDelete(sqlite3 *, Table*);
+SQLITE_PRIVATE int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
+#else
+ #define sqlite3FkDelete(a,b)
+ #define sqlite3FkLocateIndex(a,b,c,d,e)
+#endif
+
+
+/*
+** Available fault injectors. Should be numbered beginning with 0.
+*/
+#define SQLITE_FAULTINJECTOR_MALLOC 0
+#define SQLITE_FAULTINJECTOR_COUNT 1
+
+/*
+** The interface to the code in fault.c used for identifying "benign"
+** malloc failures. This is only present if SQLITE_UNTESTABLE
+** is not defined.
+*/
+#ifndef SQLITE_UNTESTABLE
+SQLITE_PRIVATE void sqlite3BeginBenignMalloc(void);
+SQLITE_PRIVATE void sqlite3EndBenignMalloc(void);
+#else
+ #define sqlite3BeginBenignMalloc()
+ #define sqlite3EndBenignMalloc()
+#endif
+
+/*
+** Allowed return values from sqlite3FindInIndex()
+*/
+#define IN_INDEX_ROWID 1 /* Search the rowid of the table */
+#define IN_INDEX_EPH 2 /* Search an ephemeral b-tree */
+#define IN_INDEX_INDEX_ASC 3 /* Existing index ASCENDING */
+#define IN_INDEX_INDEX_DESC 4 /* Existing index DESCENDING */
+#define IN_INDEX_NOOP 5 /* No table available. Use comparisons */
+/*
+** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
+*/
+#define IN_INDEX_NOOP_OK 0x0001 /* OK to return IN_INDEX_NOOP */
+#define IN_INDEX_MEMBERSHIP 0x0002 /* IN operator used for membership test */
+#define IN_INDEX_LOOP 0x0004 /* IN operator used as a loop */
+SQLITE_PRIVATE int sqlite3FindInIndex(Parse *, Expr *, u32, int*, int*);
+
+SQLITE_PRIVATE int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
+SQLITE_PRIVATE int sqlite3JournalSize(sqlite3_vfs *);
+#if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
+ || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
+SQLITE_PRIVATE int sqlite3JournalCreate(sqlite3_file *);
+#endif
+
+SQLITE_PRIVATE int sqlite3JournalIsInMemory(sqlite3_file *p);
+SQLITE_PRIVATE void sqlite3MemJournalOpen(sqlite3_file *);
+
+SQLITE_PRIVATE void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p);
+#if SQLITE_MAX_EXPR_DEPTH>0
+SQLITE_PRIVATE int sqlite3SelectExprHeight(Select *);
+SQLITE_PRIVATE int sqlite3ExprCheckHeight(Parse*, int);
+#else
+ #define sqlite3SelectExprHeight(x) 0
+ #define sqlite3ExprCheckHeight(x,y)
+#endif
+
+SQLITE_PRIVATE u32 sqlite3Get4byte(const u8*);
+SQLITE_PRIVATE void sqlite3Put4byte(u8*, u32);
+
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+SQLITE_PRIVATE void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
+SQLITE_PRIVATE void sqlite3ConnectionUnlocked(sqlite3 *db);
+SQLITE_PRIVATE void sqlite3ConnectionClosed(sqlite3 *db);
+#else
+ #define sqlite3ConnectionBlocked(x,y)
+ #define sqlite3ConnectionUnlocked(x)
+ #define sqlite3ConnectionClosed(x)
+#endif
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3ParserTrace(FILE*, char *);
+#endif
+#if defined(YYCOVERAGE)
+SQLITE_PRIVATE int sqlite3ParserCoverage(FILE*);
+#endif
+
+/*
+** If the SQLITE_ENABLE IOTRACE exists then the global variable
+** sqlite3IoTrace is a pointer to a printf-like routine used to
+** print I/O tracing messages.
+*/
+#ifdef SQLITE_ENABLE_IOTRACE
+# define IOTRACE(A) if( sqlite3IoTrace ){ sqlite3IoTrace A; }
+SQLITE_PRIVATE void sqlite3VdbeIOTraceSql(Vdbe*);
+SQLITE_API SQLITE_EXTERN void (SQLITE_CDECL *sqlite3IoTrace)(const char*,...);
+#else
+# define IOTRACE(A)
+# define sqlite3VdbeIOTraceSql(X)
+#endif
+
+/*
+** These routines are available for the mem2.c debugging memory allocator
+** only. They are used to verify that different "types" of memory
+** allocations are properly tracked by the system.
+**
+** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
+** the MEMTYPE_* macros defined below. The type must be a bitmask with
+** a single bit set.
+**
+** sqlite3MemdebugHasType() returns true if any of the bits in its second
+** argument match the type set by the previous sqlite3MemdebugSetType().
+** sqlite3MemdebugHasType() is intended for use inside assert() statements.
+**
+** sqlite3MemdebugNoType() returns true if none of the bits in its second
+** argument match the type set by the previous sqlite3MemdebugSetType().
+**
+** Perhaps the most important point is the difference between MEMTYPE_HEAP
+** and MEMTYPE_LOOKASIDE. If an allocation is MEMTYPE_LOOKASIDE, that means
+** it might have been allocated by lookaside, except the allocation was
+** too large or lookaside was already full. It is important to verify
+** that allocations that might have been satisfied by lookaside are not
+** passed back to non-lookaside free() routines. Asserts such as the
+** example above are placed on the non-lookaside free() routines to verify
+** this constraint.
+**
+** All of this is no-op for a production build. It only comes into
+** play when the SQLITE_MEMDEBUG compile-time option is used.
+*/
+#ifdef SQLITE_MEMDEBUG
+SQLITE_PRIVATE void sqlite3MemdebugSetType(void*,u8);
+SQLITE_PRIVATE int sqlite3MemdebugHasType(void*,u8);
+SQLITE_PRIVATE int sqlite3MemdebugNoType(void*,u8);
+#else
+# define sqlite3MemdebugSetType(X,Y) /* no-op */
+# define sqlite3MemdebugHasType(X,Y) 1
+# define sqlite3MemdebugNoType(X,Y) 1
+#endif
+#define MEMTYPE_HEAP 0x01 /* General heap allocations */
+#define MEMTYPE_LOOKASIDE 0x02 /* Heap that might have been lookaside */
+#define MEMTYPE_PCACHE 0x04 /* Page cache allocations */
+
+/*
+** Threading interface
+*/
+#if SQLITE_MAX_WORKER_THREADS>0
+SQLITE_PRIVATE int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
+SQLITE_PRIVATE int sqlite3ThreadJoin(SQLiteThread*, void**);
+#endif
+
+#if defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)
+SQLITE_PRIVATE int sqlite3DbpageRegister(sqlite3*);
+#endif
+#if defined(SQLITE_ENABLE_DBSTAT_VTAB) || defined(SQLITE_TEST)
+SQLITE_PRIVATE int sqlite3DbstatRegister(sqlite3*);
+#endif
+
+SQLITE_PRIVATE int sqlite3ExprVectorSize(Expr *pExpr);
+SQLITE_PRIVATE int sqlite3ExprIsVector(Expr *pExpr);
+SQLITE_PRIVATE Expr *sqlite3VectorFieldSubexpr(Expr*, int);
+SQLITE_PRIVATE Expr *sqlite3ExprForVectorField(Parse*,Expr*,int);
+SQLITE_PRIVATE void sqlite3VectorErrorMsg(Parse*, Expr*);
+
+#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
+SQLITE_PRIVATE const char **sqlite3CompileOptions(int *pnOpt);
+#endif
+
+#endif /* SQLITEINT_H */
+
+/************** End of sqliteInt.h *******************************************/
+/************** Begin file global.c ******************************************/
+/*
+** 2008 June 13
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains definitions of global variables and constants.
+*/
+/* #include "sqliteInt.h" */
+
+/* An array to map all upper-case characters into their corresponding
+** lower-case character.
+**
+** SQLite only considers US-ASCII (or EBCDIC) characters. We do not
+** handle case conversions for the UTF character set since the tables
+** involved are nearly as big or bigger than SQLite itself.
+*/
+SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[] = {
+#ifdef SQLITE_ASCII
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
+ 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
+ 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
+ 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 97, 98, 99,100,101,102,103,
+ 104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,
+ 122, 91, 92, 93, 94, 95, 96, 97, 98, 99,100,101,102,103,104,105,106,107,
+ 108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,
+ 126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
+ 144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,
+ 162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,
+ 180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,
+ 198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,
+ 216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,
+ 234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,
+ 252,253,254,255
+#endif
+#ifdef SQLITE_EBCDIC
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 0x */
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, /* 1x */
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, /* 2x */
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, /* 3x */
+ 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, /* 4x */
+ 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, /* 5x */
+ 96, 97, 98, 99,100,101,102,103,104,105,106,107,108,109,110,111, /* 6x */
+ 112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127, /* 7x */
+ 128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143, /* 8x */
+ 144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159, /* 9x */
+ 160,161,162,163,164,165,166,167,168,169,170,171,140,141,142,175, /* Ax */
+ 176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191, /* Bx */
+ 192,129,130,131,132,133,134,135,136,137,202,203,204,205,206,207, /* Cx */
+ 208,145,146,147,148,149,150,151,152,153,218,219,220,221,222,223, /* Dx */
+ 224,225,162,163,164,165,166,167,168,169,234,235,236,237,238,239, /* Ex */
+ 240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255, /* Fx */
+#endif
+};
+
+/*
+** The following 256 byte lookup table is used to support SQLites built-in
+** equivalents to the following standard library functions:
+**
+** isspace() 0x01
+** isalpha() 0x02
+** isdigit() 0x04
+** isalnum() 0x06
+** isxdigit() 0x08
+** toupper() 0x20
+** SQLite identifier character 0x40
+** Quote character 0x80
+**
+** Bit 0x20 is set if the mapped character requires translation to upper
+** case. i.e. if the character is a lower-case ASCII character.
+** If x is a lower-case ASCII character, then its upper-case equivalent
+** is (x - 0x20). Therefore toupper() can be implemented as:
+**
+** (x & ~(map[x]&0x20))
+**
+** The equivalent of tolower() is implemented using the sqlite3UpperToLower[]
+** array. tolower() is used more often than toupper() by SQLite.
+**
+** Bit 0x40 is set if the character is non-alphanumeric and can be used in an
+** SQLite identifier. Identifiers are alphanumerics, "_", "$", and any
+** non-ASCII UTF character. Hence the test for whether or not a character is
+** part of an identifier is 0x46.
+*/
+#ifdef SQLITE_ASCII
+SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[256] = {
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 00..07 ........ */
+ 0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, /* 08..0f ........ */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 10..17 ........ */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 18..1f ........ */
+ 0x01, 0x00, 0x80, 0x00, 0x40, 0x00, 0x00, 0x80, /* 20..27 !"#$%&' */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 28..2f ()*+,-./ */
+ 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, /* 30..37 01234567 */
+ 0x0c, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 38..3f 89:;<=>? */
+
+ 0x00, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x02, /* 40..47 @ABCDEFG */
+ 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, /* 48..4f HIJKLMNO */
+ 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, /* 50..57 PQRSTUVW */
+ 0x02, 0x02, 0x02, 0x80, 0x00, 0x00, 0x00, 0x40, /* 58..5f XYZ[\]^_ */
+ 0x80, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x22, /* 60..67 `abcdefg */
+ 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, /* 68..6f hijklmno */
+ 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, /* 70..77 pqrstuvw */
+ 0x22, 0x22, 0x22, 0x00, 0x00, 0x00, 0x00, 0x00, /* 78..7f xyz{|}~. */
+
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* 80..87 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* 88..8f ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* 90..97 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* 98..9f ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* a0..a7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* a8..af ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* b0..b7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* b8..bf ........ */
+
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* c0..c7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* c8..cf ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* d0..d7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* d8..df ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* e0..e7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* e8..ef ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* f0..f7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40 /* f8..ff ........ */
+};
+#endif
+
+/* EVIDENCE-OF: R-02982-34736 In order to maintain full backwards
+** compatibility for legacy applications, the URI filename capability is
+** disabled by default.
+**
+** EVIDENCE-OF: R-38799-08373 URI filenames can be enabled or disabled
+** using the SQLITE_USE_URI=1 or SQLITE_USE_URI=0 compile-time options.
+**
+** EVIDENCE-OF: R-43642-56306 By default, URI handling is globally
+** disabled. The default value may be changed by compiling with the
+** SQLITE_USE_URI symbol defined.
+**
+** URI filenames are enabled by default if SQLITE_HAS_CODEC is
+** enabled.
+*/
+#ifndef SQLITE_USE_URI
+# ifdef SQLITE_HAS_CODEC
+# define SQLITE_USE_URI 1
+# else
+# define SQLITE_USE_URI 0
+# endif
+#endif
+
+/* EVIDENCE-OF: R-38720-18127 The default setting is determined by the
+** SQLITE_ALLOW_COVERING_INDEX_SCAN compile-time option, or is "on" if
+** that compile-time option is omitted.
+*/
+#ifndef SQLITE_ALLOW_COVERING_INDEX_SCAN
+# define SQLITE_ALLOW_COVERING_INDEX_SCAN 1
+#endif
+
+/* The minimum PMA size is set to this value multiplied by the database
+** page size in bytes.
+*/
+#ifndef SQLITE_SORTER_PMASZ
+# define SQLITE_SORTER_PMASZ 250
+#endif
+
+/* Statement journals spill to disk when their size exceeds the following
+** threshold (in bytes). 0 means that statement journals are created and
+** written to disk immediately (the default behavior for SQLite versions
+** before 3.12.0). -1 means always keep the entire statement journal in
+** memory. (The statement journal is also always held entirely in memory
+** if journal_mode=MEMORY or if temp_store=MEMORY, regardless of this
+** setting.)
+*/
+#ifndef SQLITE_STMTJRNL_SPILL
+# define SQLITE_STMTJRNL_SPILL (64*1024)
+#endif
+
+/*
+** The default lookaside-configuration, the format "SZ,N". SZ is the
+** number of bytes in each lookaside slot (should be a multiple of 8)
+** and N is the number of slots. The lookaside-configuration can be
+** changed as start-time using sqlite3_config(SQLITE_CONFIG_LOOKASIDE)
+** or at run-time for an individual database connection using
+** sqlite3_db_config(db, SQLITE_DBCONFIG_LOOKASIDE);
+*/
+#ifndef SQLITE_DEFAULT_LOOKASIDE
+# define SQLITE_DEFAULT_LOOKASIDE 1200,100
+#endif
+
+
+/*
+** The following singleton contains the global configuration for
+** the SQLite library.
+*/
+SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config = {
+ SQLITE_DEFAULT_MEMSTATUS, /* bMemstat */
+ 1, /* bCoreMutex */
+ SQLITE_THREADSAFE==1, /* bFullMutex */
+ SQLITE_USE_URI, /* bOpenUri */
+ SQLITE_ALLOW_COVERING_INDEX_SCAN, /* bUseCis */
+ 0, /* bSmallMalloc */
+ 0x7ffffffe, /* mxStrlen */
+ 0, /* neverCorrupt */
+ SQLITE_DEFAULT_LOOKASIDE, /* szLookaside, nLookaside */
+ SQLITE_STMTJRNL_SPILL, /* nStmtSpill */
+ {0,0,0,0,0,0,0,0}, /* m */
+ {0,0,0,0,0,0,0,0,0}, /* mutex */
+ {0,0,0,0,0,0,0,0,0,0,0,0,0},/* pcache2 */
+ (void*)0, /* pHeap */
+ 0, /* nHeap */
+ 0, 0, /* mnHeap, mxHeap */
+ SQLITE_DEFAULT_MMAP_SIZE, /* szMmap */
+ SQLITE_MAX_MMAP_SIZE, /* mxMmap */
+ (void*)0, /* pPage */
+ 0, /* szPage */
+ SQLITE_DEFAULT_PCACHE_INITSZ, /* nPage */
+ 0, /* mxParserStack */
+ 0, /* sharedCacheEnabled */
+ SQLITE_SORTER_PMASZ, /* szPma */
+ /* All the rest should always be initialized to zero */
+ 0, /* isInit */
+ 0, /* inProgress */
+ 0, /* isMutexInit */
+ 0, /* isMallocInit */
+ 0, /* isPCacheInit */
+ 0, /* nRefInitMutex */
+ 0, /* pInitMutex */
+ 0, /* xLog */
+ 0, /* pLogArg */
+#ifdef SQLITE_ENABLE_SQLLOG
+ 0, /* xSqllog */
+ 0, /* pSqllogArg */
+#endif
+#ifdef SQLITE_VDBE_COVERAGE
+ 0, /* xVdbeBranch */
+ 0, /* pVbeBranchArg */
+#endif
+#ifndef SQLITE_UNTESTABLE
+ 0, /* xTestCallback */
+#endif
+ 0, /* bLocaltimeFault */
+ 0x7ffffffe, /* iOnceResetThreshold */
+ SQLITE_DEFAULT_SORTERREF_SIZE /* szSorterRef */
+};
+
+/*
+** Hash table for global functions - functions common to all
+** database connections. After initialization, this table is
+** read-only.
+*/
+SQLITE_PRIVATE FuncDefHash sqlite3BuiltinFunctions;
+
+/*
+** Constant tokens for values 0 and 1.
+*/
+SQLITE_PRIVATE const Token sqlite3IntTokens[] = {
+ { "0", 1 },
+ { "1", 1 }
+};
+
+#ifdef VDBE_PROFILE
+/*
+** The following performance counter can be used in place of
+** sqlite3Hwtime() for profiling. This is a no-op on standard builds.
+*/
+SQLITE_PRIVATE sqlite3_uint64 sqlite3NProfileCnt = 0;
+#endif
+
+/*
+** The value of the "pending" byte must be 0x40000000 (1 byte past the
+** 1-gibabyte boundary) in a compatible database. SQLite never uses
+** the database page that contains the pending byte. It never attempts
+** to read or write that page. The pending byte page is set aside
+** for use by the VFS layers as space for managing file locks.
+**
+** During testing, it is often desirable to move the pending byte to
+** a different position in the file. This allows code that has to
+** deal with the pending byte to run on files that are much smaller
+** than 1 GiB. The sqlite3_test_control() interface can be used to
+** move the pending byte.
+**
+** IMPORTANT: Changing the pending byte to any value other than
+** 0x40000000 results in an incompatible database file format!
+** Changing the pending byte during operation will result in undefined
+** and incorrect behavior.
+*/
+#ifndef SQLITE_OMIT_WSD
+SQLITE_PRIVATE int sqlite3PendingByte = 0x40000000;
+#endif
+
+/* #include "opcodes.h" */
+/*
+** Properties of opcodes. The OPFLG_INITIALIZER macro is
+** created by mkopcodeh.awk during compilation. Data is obtained
+** from the comments following the "case OP_xxxx:" statements in
+** the vdbe.c file.
+*/
+SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[] = OPFLG_INITIALIZER;
+
+/*
+** Name of the default collating sequence
+*/
+SQLITE_PRIVATE const char sqlite3StrBINARY[] = "BINARY";
+
+/************** End of global.c **********************************************/
+/************** Begin file status.c ******************************************/
+/*
+** 2008 June 18
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This module implements the sqlite3_status() interface and related
+** functionality.
+*/
+/* #include "sqliteInt.h" */
+/************** Include vdbeInt.h in the middle of status.c ******************/
+/************** Begin file vdbeInt.h *****************************************/
+/*
+** 2003 September 6
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the header file for information that is private to the
+** VDBE. This information used to all be at the top of the single
+** source code file "vdbe.c". When that file became too big (over
+** 6000 lines long) it was split up into several smaller files and
+** this header information was factored out.
+*/
+#ifndef SQLITE_VDBEINT_H
+#define SQLITE_VDBEINT_H
+
+/*
+** The maximum number of times that a statement will try to reparse
+** itself before giving up and returning SQLITE_SCHEMA.
+*/
+#ifndef SQLITE_MAX_SCHEMA_RETRY
+# define SQLITE_MAX_SCHEMA_RETRY 50
+#endif
+
+/*
+** VDBE_DISPLAY_P4 is true or false depending on whether or not the
+** "explain" P4 display logic is enabled.
+*/
+#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
+ || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
+# define VDBE_DISPLAY_P4 1
+#else
+# define VDBE_DISPLAY_P4 0
+#endif
+
+/*
+** SQL is translated into a sequence of instructions to be
+** executed by a virtual machine. Each instruction is an instance
+** of the following structure.
+*/
+typedef struct VdbeOp Op;
+
+/*
+** Boolean values
+*/
+typedef unsigned Bool;
+
+/* Opaque type used by code in vdbesort.c */
+typedef struct VdbeSorter VdbeSorter;
+
+/* Elements of the linked list at Vdbe.pAuxData */
+typedef struct AuxData AuxData;
+
+/* Types of VDBE cursors */
+#define CURTYPE_BTREE 0
+#define CURTYPE_SORTER 1
+#define CURTYPE_VTAB 2
+#define CURTYPE_PSEUDO 3
+
+/*
+** A VdbeCursor is an superclass (a wrapper) for various cursor objects:
+**
+** * A b-tree cursor
+** - In the main database or in an ephemeral database
+** - On either an index or a table
+** * A sorter
+** * A virtual table
+** * A one-row "pseudotable" stored in a single register
+*/
+typedef struct VdbeCursor VdbeCursor;
+struct VdbeCursor {
+ u8 eCurType; /* One of the CURTYPE_* values above */
+ i8 iDb; /* Index of cursor database in db->aDb[] (or -1) */
+ u8 nullRow; /* True if pointing to a row with no data */
+ u8 deferredMoveto; /* A call to sqlite3BtreeMoveto() is needed */
+ u8 isTable; /* True for rowid tables. False for indexes */
+#ifdef SQLITE_DEBUG
+ u8 seekOp; /* Most recent seek operation on this cursor */
+ u8 wrFlag; /* The wrFlag argument to sqlite3BtreeCursor() */
+#endif
+ Bool isEphemeral:1; /* True for an ephemeral table */
+ Bool useRandomRowid:1; /* Generate new record numbers semi-randomly */
+ Bool isOrdered:1; /* True if the table is not BTREE_UNORDERED */
+ Bool seekHit:1; /* See the OP_SeekHit and OP_IfNoHope opcodes */
+ Btree *pBtx; /* Separate file holding temporary table */
+ i64 seqCount; /* Sequence counter */
+ int *aAltMap; /* Mapping from table to index column numbers */
+
+ /* Cached OP_Column parse information is only valid if cacheStatus matches
+ ** Vdbe.cacheCtr. Vdbe.cacheCtr will never take on the value of
+ ** CACHE_STALE (0) and so setting cacheStatus=CACHE_STALE guarantees that
+ ** the cache is out of date. */
+ u32 cacheStatus; /* Cache is valid if this matches Vdbe.cacheCtr */
+ int seekResult; /* Result of previous sqlite3BtreeMoveto() or 0
+ ** if there have been no prior seeks on the cursor. */
+ /* seekResult does not distinguish between "no seeks have ever occurred
+ ** on this cursor" and "the most recent seek was an exact match".
+ ** For CURTYPE_PSEUDO, seekResult is the register holding the record */
+
+ /* When a new VdbeCursor is allocated, only the fields above are zeroed.
+ ** The fields that follow are uninitialized, and must be individually
+ ** initialized prior to first use. */
+ VdbeCursor *pAltCursor; /* Associated index cursor from which to read */
+ union {
+ BtCursor *pCursor; /* CURTYPE_BTREE or _PSEUDO. Btree cursor */
+ sqlite3_vtab_cursor *pVCur; /* CURTYPE_VTAB. Vtab cursor */
+ VdbeSorter *pSorter; /* CURTYPE_SORTER. Sorter object */
+ } uc;
+ KeyInfo *pKeyInfo; /* Info about index keys needed by index cursors */
+ u32 iHdrOffset; /* Offset to next unparsed byte of the header */
+ Pgno pgnoRoot; /* Root page of the open btree cursor */
+ i16 nField; /* Number of fields in the header */
+ u16 nHdrParsed; /* Number of header fields parsed so far */
+ i64 movetoTarget; /* Argument to the deferred sqlite3BtreeMoveto() */
+ u32 *aOffset; /* Pointer to aType[nField] */
+ const u8 *aRow; /* Data for the current row, if all on one page */
+ u32 payloadSize; /* Total number of bytes in the record */
+ u32 szRow; /* Byte available in aRow */
+#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
+ u64 maskUsed; /* Mask of columns used by this cursor */
+#endif
+
+ /* 2*nField extra array elements allocated for aType[], beyond the one
+ ** static element declared in the structure. nField total array slots for
+ ** aType[] and nField+1 array slots for aOffset[] */
+ u32 aType[1]; /* Type values record decode. MUST BE LAST */
+};
+
+
+/*
+** A value for VdbeCursor.cacheStatus that means the cache is always invalid.
+*/
+#define CACHE_STALE 0
+
+/*
+** When a sub-program is executed (OP_Program), a structure of this type
+** is allocated to store the current value of the program counter, as
+** well as the current memory cell array and various other frame specific
+** values stored in the Vdbe struct. When the sub-program is finished,
+** these values are copied back to the Vdbe from the VdbeFrame structure,
+** restoring the state of the VM to as it was before the sub-program
+** began executing.
+**
+** The memory for a VdbeFrame object is allocated and managed by a memory
+** cell in the parent (calling) frame. When the memory cell is deleted or
+** overwritten, the VdbeFrame object is not freed immediately. Instead, it
+** is linked into the Vdbe.pDelFrame list. The contents of the Vdbe.pDelFrame
+** list is deleted when the VM is reset in VdbeHalt(). The reason for doing
+** this instead of deleting the VdbeFrame immediately is to avoid recursive
+** calls to sqlite3VdbeMemRelease() when the memory cells belonging to the
+** child frame are released.
+**
+** The currently executing frame is stored in Vdbe.pFrame. Vdbe.pFrame is
+** set to NULL if the currently executing frame is the main program.
+*/
+typedef struct VdbeFrame VdbeFrame;
+struct VdbeFrame {
+ Vdbe *v; /* VM this frame belongs to */
+ VdbeFrame *pParent; /* Parent of this frame, or NULL if parent is main */
+ Op *aOp; /* Program instructions for parent frame */
+ i64 *anExec; /* Event counters from parent frame */
+ Mem *aMem; /* Array of memory cells for parent frame */
+ VdbeCursor **apCsr; /* Array of Vdbe cursors for parent frame */
+ u8 *aOnce; /* Bitmask used by OP_Once */
+ void *token; /* Copy of SubProgram.token */
+ i64 lastRowid; /* Last insert rowid (sqlite3.lastRowid) */
+ AuxData *pAuxData; /* Linked list of auxdata allocations */
+#if SQLITE_DEBUG
+ u32 iFrameMagic; /* magic number for sanity checking */
+#endif
+ int nCursor; /* Number of entries in apCsr */
+ int pc; /* Program Counter in parent (calling) frame */
+ int nOp; /* Size of aOp array */
+ int nMem; /* Number of entries in aMem */
+ int nChildMem; /* Number of memory cells for child frame */
+ int nChildCsr; /* Number of cursors for child frame */
+ int nChange; /* Statement changes (Vdbe.nChange) */
+ int nDbChange; /* Value of db->nChange */
+};
+
+/* Magic number for sanity checking on VdbeFrame objects */
+#define SQLITE_FRAME_MAGIC 0x879fb71e
+
+/*
+** Return a pointer to the array of registers allocated for use
+** by a VdbeFrame.
+*/
+#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
+
+/*
+** Internally, the vdbe manipulates nearly all SQL values as Mem
+** structures. Each Mem struct may cache multiple representations (string,
+** integer etc.) of the same value.
+*/
+struct sqlite3_value {
+ union MemValue {
+ double r; /* Real value used when MEM_Real is set in flags */
+ i64 i; /* Integer value used when MEM_Int is set in flags */
+ int nZero; /* Extra zero bytes when MEM_Zero and MEM_Blob set */
+ const char *zPType; /* Pointer type when MEM_Term|MEM_Subtype|MEM_Null */
+ FuncDef *pDef; /* Used only when flags==MEM_Agg */
+ } u;
+ u16 flags; /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
+ u8 enc; /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
+ u8 eSubtype; /* Subtype for this value */
+ int n; /* Number of characters in string value, excluding '\0' */
+ char *z; /* String or BLOB value */
+ /* ShallowCopy only needs to copy the information above */
+ char *zMalloc; /* Space to hold MEM_Str or MEM_Blob if szMalloc>0 */
+ int szMalloc; /* Size of the zMalloc allocation */
+ u32 uTemp; /* Transient storage for serial_type in OP_MakeRecord */
+ sqlite3 *db; /* The associated database connection */
+ void (*xDel)(void*);/* Destructor for Mem.z - only valid if MEM_Dyn */
+#ifdef SQLITE_DEBUG
+ Mem *pScopyFrom; /* This Mem is a shallow copy of pScopyFrom */
+ u16 mScopyFlags; /* flags value immediately after the shallow copy */
+#endif
+};
+
+/*
+** Size of struct Mem not including the Mem.zMalloc member or anything that
+** follows.
+*/
+#define MEMCELLSIZE offsetof(Mem,zMalloc)
+
+/* One or more of the following flags are set to indicate the validOK
+** representations of the value stored in the Mem struct.
+**
+** If the MEM_Null flag is set, then the value is an SQL NULL value.
+** For a pointer type created using sqlite3_bind_pointer() or
+** sqlite3_result_pointer() the MEM_Term and MEM_Subtype flags are also set.
+**
+** If the MEM_Str flag is set then Mem.z points at a string representation.
+** Usually this is encoded in the same unicode encoding as the main
+** database (see below for exceptions). If the MEM_Term flag is also
+** set, then the string is nul terminated. The MEM_Int and MEM_Real
+** flags may coexist with the MEM_Str flag.
+*/
+#define MEM_Null 0x0001 /* Value is NULL (or a pointer) */
+#define MEM_Str 0x0002 /* Value is a string */
+#define MEM_Int 0x0004 /* Value is an integer */
+#define MEM_Real 0x0008 /* Value is a real number */
+#define MEM_Blob 0x0010 /* Value is a BLOB */
+#define MEM_AffMask 0x001f /* Mask of affinity bits */
+/* Available 0x0020 */
+/* Available 0x0040 */
+#define MEM_Undefined 0x0080 /* Value is undefined */
+#define MEM_Cleared 0x0100 /* NULL set by OP_Null, not from data */
+#define MEM_TypeMask 0xc1ff /* Mask of type bits */
+
+
+/* Whenever Mem contains a valid string or blob representation, one of
+** the following flags must be set to determine the memory management
+** policy for Mem.z. The MEM_Term flag tells us whether or not the
+** string is \000 or \u0000 terminated
+*/
+#define MEM_Term 0x0200 /* String in Mem.z is zero terminated */
+#define MEM_Dyn 0x0400 /* Need to call Mem.xDel() on Mem.z */
+#define MEM_Static 0x0800 /* Mem.z points to a static string */
+#define MEM_Ephem 0x1000 /* Mem.z points to an ephemeral string */
+#define MEM_Agg 0x2000 /* Mem.z points to an agg function context */
+#define MEM_Zero 0x4000 /* Mem.i contains count of 0s appended to blob */
+#define MEM_Subtype 0x8000 /* Mem.eSubtype is valid */
+#ifdef SQLITE_OMIT_INCRBLOB
+ #undef MEM_Zero
+ #define MEM_Zero 0x0000
+#endif
+
+/* Return TRUE if Mem X contains dynamically allocated content - anything
+** that needs to be deallocated to avoid a leak.
+*/
+#define VdbeMemDynamic(X) \
+ (((X)->flags&(MEM_Agg|MEM_Dyn))!=0)
+
+/*
+** Clear any existing type flags from a Mem and replace them with f
+*/
+#define MemSetTypeFlag(p, f) \
+ ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
+
+/*
+** Return true if a memory cell is not marked as invalid. This macro
+** is for use inside assert() statements only.
+*/
+#ifdef SQLITE_DEBUG
+#define memIsValid(M) ((M)->flags & MEM_Undefined)==0
+#endif
+
+/*
+** Each auxiliary data pointer stored by a user defined function
+** implementation calling sqlite3_set_auxdata() is stored in an instance
+** of this structure. All such structures associated with a single VM
+** are stored in a linked list headed at Vdbe.pAuxData. All are destroyed
+** when the VM is halted (if not before).
+*/
+struct AuxData {
+ int iAuxOp; /* Instruction number of OP_Function opcode */
+ int iAuxArg; /* Index of function argument. */
+ void *pAux; /* Aux data pointer */
+ void (*xDeleteAux)(void*); /* Destructor for the aux data */
+ AuxData *pNextAux; /* Next element in list */
+};
+
+/*
+** The "context" argument for an installable function. A pointer to an
+** instance of this structure is the first argument to the routines used
+** implement the SQL functions.
+**
+** There is a typedef for this structure in sqlite.h. So all routines,
+** even the public interface to SQLite, can use a pointer to this structure.
+** But this file is the only place where the internal details of this
+** structure are known.
+**
+** This structure is defined inside of vdbeInt.h because it uses substructures
+** (Mem) which are only defined there.
+*/
+struct sqlite3_context {
+ Mem *pOut; /* The return value is stored here */
+ FuncDef *pFunc; /* Pointer to function information */
+ Mem *pMem; /* Memory cell used to store aggregate context */
+ Vdbe *pVdbe; /* The VM that owns this context */
+ int iOp; /* Instruction number of OP_Function */
+ int isError; /* Error code returned by the function. */
+ u8 skipFlag; /* Skip accumulator loading if true */
+ u8 argc; /* Number of arguments */
+ sqlite3_value *argv[1]; /* Argument set */
+};
+
+/* A bitfield type for use inside of structures. Always follow with :N where
+** N is the number of bits.
+*/
+typedef unsigned bft; /* Bit Field Type */
+
+typedef struct ScanStatus ScanStatus;
+struct ScanStatus {
+ int addrExplain; /* OP_Explain for loop */
+ int addrLoop; /* Address of "loops" counter */
+ int addrVisit; /* Address of "rows visited" counter */
+ int iSelectID; /* The "Select-ID" for this loop */
+ LogEst nEst; /* Estimated output rows per loop */
+ char *zName; /* Name of table or index */
+};
+
+/*
+** An instance of the virtual machine. This structure contains the complete
+** state of the virtual machine.
+**
+** The "sqlite3_stmt" structure pointer that is returned by sqlite3_prepare()
+** is really a pointer to an instance of this structure.
+*/
+struct Vdbe {
+ sqlite3 *db; /* The database connection that owns this statement */
+ Vdbe *pPrev,*pNext; /* Linked list of VDBEs with the same Vdbe.db */
+ Parse *pParse; /* Parsing context used to create this Vdbe */
+ ynVar nVar; /* Number of entries in aVar[] */
+ u32 magic; /* Magic number for sanity checking */
+ int nMem; /* Number of memory locations currently allocated */
+ int nCursor; /* Number of slots in apCsr[] */
+ u32 cacheCtr; /* VdbeCursor row cache generation counter */
+ int pc; /* The program counter */
+ int rc; /* Value to return */
+ int nChange; /* Number of db changes made since last reset */
+ int iStatement; /* Statement number (or 0 if has not opened stmt) */
+ i64 iCurrentTime; /* Value of julianday('now') for this statement */
+ i64 nFkConstraint; /* Number of imm. FK constraints this VM */
+ i64 nStmtDefCons; /* Number of def. constraints when stmt started */
+ i64 nStmtDefImmCons; /* Number of def. imm constraints when stmt started */
+
+ /* When allocating a new Vdbe object, all of the fields below should be
+ ** initialized to zero or NULL */
+
+ Op *aOp; /* Space to hold the virtual machine's program */
+ Mem *aMem; /* The memory locations */
+ Mem **apArg; /* Arguments to currently executing user function */
+ Mem *aColName; /* Column names to return */
+ Mem *pResultSet; /* Pointer to an array of results */
+ char *zErrMsg; /* Error message written here */
+ VdbeCursor **apCsr; /* One element of this array for each open cursor */
+ Mem *aVar; /* Values for the OP_Variable opcode. */
+ VList *pVList; /* Name of variables */
+#ifndef SQLITE_OMIT_TRACE
+ i64 startTime; /* Time when query started - used for profiling */
+#endif
+ int nOp; /* Number of instructions in the program */
+#ifdef SQLITE_DEBUG
+ int rcApp; /* errcode set by sqlite3_result_error_code() */
+ u32 nWrite; /* Number of write operations that have occurred */
+#endif
+ u16 nResColumn; /* Number of columns in one row of the result set */
+ u8 errorAction; /* Recovery action to do in case of an error */
+ u8 minWriteFileFormat; /* Minimum file format for writable database files */
+ u8 prepFlags; /* SQLITE_PREPARE_* flags */
+ bft expired:2; /* 1: recompile VM immediately 2: when convenient */
+ bft explain:2; /* True if EXPLAIN present on SQL command */
+ bft doingRerun:1; /* True if rerunning after an auto-reprepare */
+ bft changeCntOn:1; /* True to update the change-counter */
+ bft runOnlyOnce:1; /* Automatically expire on reset */
+ bft usesStmtJournal:1; /* True if uses a statement journal */
+ bft readOnly:1; /* True for statements that do not write */
+ bft bIsReader:1; /* True for statements that read */
+ yDbMask btreeMask; /* Bitmask of db->aDb[] entries referenced */
+ yDbMask lockMask; /* Subset of btreeMask that requires a lock */
+ u32 aCounter[7]; /* Counters used by sqlite3_stmt_status() */
+ char *zSql; /* Text of the SQL statement that generated this */
+ void *pFree; /* Free this when deleting the vdbe */
+ VdbeFrame *pFrame; /* Parent frame */
+ VdbeFrame *pDelFrame; /* List of frame objects to free on VM reset */
+ int nFrame; /* Number of frames in pFrame list */
+ u32 expmask; /* Binding to these vars invalidates VM */
+ SubProgram *pProgram; /* Linked list of all sub-programs used by VM */
+ AuxData *pAuxData; /* Linked list of auxdata allocations */
+#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
+ i64 *anExec; /* Number of times each op has been executed */
+ int nScan; /* Entries in aScan[] */
+ ScanStatus *aScan; /* Scan definitions for sqlite3_stmt_scanstatus() */
+#endif
+};
+
+/*
+** The following are allowed values for Vdbe.magic
+*/
+#define VDBE_MAGIC_INIT 0x16bceaa5 /* Building a VDBE program */
+#define VDBE_MAGIC_RUN 0x2df20da3 /* VDBE is ready to execute */
+#define VDBE_MAGIC_HALT 0x319c2973 /* VDBE has completed execution */
+#define VDBE_MAGIC_RESET 0x48fa9f76 /* Reset and ready to run again */
+#define VDBE_MAGIC_DEAD 0x5606c3c8 /* The VDBE has been deallocated */
+
+/*
+** Structure used to store the context required by the
+** sqlite3_preupdate_*() API functions.
+*/
+struct PreUpdate {
+ Vdbe *v;
+ VdbeCursor *pCsr; /* Cursor to read old values from */
+ int op; /* One of SQLITE_INSERT, UPDATE, DELETE */
+ u8 *aRecord; /* old.* database record */
+ KeyInfo keyinfo;
+ UnpackedRecord *pUnpacked; /* Unpacked version of aRecord[] */
+ UnpackedRecord *pNewUnpacked; /* Unpacked version of new.* record */
+ int iNewReg; /* Register for new.* values */
+ i64 iKey1; /* First key value passed to hook */
+ i64 iKey2; /* Second key value passed to hook */
+ Mem *aNew; /* Array of new.* values */
+ Table *pTab; /* Schema object being upated */
+ Index *pPk; /* PK index if pTab is WITHOUT ROWID */
+};
+
+/*
+** Function prototypes
+*/
+SQLITE_PRIVATE void sqlite3VdbeError(Vdbe*, const char *, ...);
+SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
+void sqliteVdbePopStack(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor**, int*);
+SQLITE_PRIVATE int sqlite3VdbeCursorRestore(VdbeCursor*);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
+SQLITE_PRIVATE u8 sqlite3VdbeOneByteSerialTypeLen(u8);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int, u32*);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, Mem*, u32);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
+SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(sqlite3*, AuxData**, int, int);
+
+int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
+SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(sqlite3*,VdbeCursor*,UnpackedRecord*,int*);
+SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor*, i64*);
+SQLITE_PRIVATE int sqlite3VdbeExec(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeList(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *, int);
+SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem*, const Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
+SQLITE_PRIVATE void sqlite3VdbeMemMove(Mem*, Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemNulTerminate(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
+SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem*, i64);
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
+#else
+SQLITE_PRIVATE void sqlite3VdbeMemSetDouble(Mem*, double);
+#endif
+SQLITE_PRIVATE void sqlite3VdbeMemSetPointer(Mem*, void*, const char*, void(*)(void*));
+SQLITE_PRIVATE void sqlite3VdbeMemInit(Mem*,sqlite3*,u16);
+SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem*,int);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3VdbeMemIsRowSet(const Mem*);
+#endif
+SQLITE_PRIVATE int sqlite3VdbeMemSetRowSet(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem*, u8, u8);
+SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem*);
+SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeBooleanValue(Mem*, int ifNull);
+SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemCast(Mem*,u8,u8);
+SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
+SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
+#ifndef SQLITE_OMIT_WINDOWFUNC
+SQLITE_PRIVATE int sqlite3VdbeMemAggValue(Mem*, Mem*, FuncDef*);
+#endif
+SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
+SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
+SQLITE_PRIVATE int sqlite3VdbeMemClearAndResize(Mem *pMem, int n);
+SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3VdbeFrameIsValid(VdbeFrame*);
+#endif
+SQLITE_PRIVATE void sqlite3VdbeFrameMemDel(void*); /* Destructor on Mem */
+SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*); /* Actually deletes the Frame */
+SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
+#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
+SQLITE_PRIVATE void sqlite3VdbePreUpdateHook(Vdbe*,VdbeCursor*,int,const char*,Table*,i64,int);
+#endif
+SQLITE_PRIVATE int sqlite3VdbeTransferError(Vdbe *p);
+
+SQLITE_PRIVATE int sqlite3VdbeSorterInit(sqlite3 *, int, VdbeCursor *);
+SQLITE_PRIVATE void sqlite3VdbeSorterReset(sqlite3 *, VdbeSorter *);
+SQLITE_PRIVATE void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
+SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
+SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *);
+SQLITE_PRIVATE int sqlite3VdbeSorterRewind(const VdbeCursor *, int *);
+SQLITE_PRIVATE int sqlite3VdbeSorterWrite(const VdbeCursor *, Mem *);
+SQLITE_PRIVATE int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int, int *);
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3VdbeIncrWriteCounter(Vdbe*, VdbeCursor*);
+SQLITE_PRIVATE void sqlite3VdbeAssertAbortable(Vdbe*);
+#else
+# define sqlite3VdbeIncrWriteCounter(V,C)
+# define sqlite3VdbeAssertAbortable(V)
+#endif
+
+#if !defined(SQLITE_OMIT_SHARED_CACHE)
+SQLITE_PRIVATE void sqlite3VdbeEnter(Vdbe*);
+#else
+# define sqlite3VdbeEnter(X)
+#endif
+
+#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
+SQLITE_PRIVATE void sqlite3VdbeLeave(Vdbe*);
+#else
+# define sqlite3VdbeLeave(X)
+#endif
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3VdbeMemAboutToChange(Vdbe*,Mem*);
+SQLITE_PRIVATE int sqlite3VdbeCheckMemInvariants(Mem*);
+#endif
+
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *, int);
+#else
+# define sqlite3VdbeCheckFk(p,i) 0
+#endif
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3VdbePrintSql(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
+#endif
+#ifndef SQLITE_OMIT_UTF16
+SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem*, u8);
+SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem);
+#endif
+
+#ifndef SQLITE_OMIT_INCRBLOB
+SQLITE_PRIVATE int sqlite3VdbeMemExpandBlob(Mem *);
+ #define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
+#else
+ #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
+ #define ExpandBlob(P) SQLITE_OK
+#endif
+
+#endif /* !defined(SQLITE_VDBEINT_H) */
+
+/************** End of vdbeInt.h *********************************************/
+/************** Continuing where we left off in status.c *********************/
+
+/*
+** Variables in which to record status information.
+*/
+#if SQLITE_PTRSIZE>4
+typedef sqlite3_int64 sqlite3StatValueType;
+#else
+typedef u32 sqlite3StatValueType;
+#endif
+typedef struct sqlite3StatType sqlite3StatType;
+static SQLITE_WSD struct sqlite3StatType {
+ sqlite3StatValueType nowValue[10]; /* Current value */
+ sqlite3StatValueType mxValue[10]; /* Maximum value */
+} sqlite3Stat = { {0,}, {0,} };
+
+/*
+** Elements of sqlite3Stat[] are protected by either the memory allocator
+** mutex, or by the pcache1 mutex. The following array determines which.
+*/
+static const char statMutex[] = {
+ 0, /* SQLITE_STATUS_MEMORY_USED */
+ 1, /* SQLITE_STATUS_PAGECACHE_USED */
+ 1, /* SQLITE_STATUS_PAGECACHE_OVERFLOW */
+ 0, /* SQLITE_STATUS_SCRATCH_USED */
+ 0, /* SQLITE_STATUS_SCRATCH_OVERFLOW */
+ 0, /* SQLITE_STATUS_MALLOC_SIZE */
+ 0, /* SQLITE_STATUS_PARSER_STACK */
+ 1, /* SQLITE_STATUS_PAGECACHE_SIZE */
+ 0, /* SQLITE_STATUS_SCRATCH_SIZE */
+ 0, /* SQLITE_STATUS_MALLOC_COUNT */
+};
+
+
+/* The "wsdStat" macro will resolve to the status information
+** state vector. If writable static data is unsupported on the target,
+** we have to locate the state vector at run-time. In the more common
+** case where writable static data is supported, wsdStat can refer directly
+** to the "sqlite3Stat" state vector declared above.
+*/
+#ifdef SQLITE_OMIT_WSD
+# define wsdStatInit sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat)
+# define wsdStat x[0]
+#else
+# define wsdStatInit
+# define wsdStat sqlite3Stat
+#endif
+
+/*
+** Return the current value of a status parameter. The caller must
+** be holding the appropriate mutex.
+*/
+SQLITE_PRIVATE sqlite3_int64 sqlite3StatusValue(int op){
+ wsdStatInit;
+ assert( op>=0 && op=0 && op=0 && op=0 && opwsdStat.mxValue[op] ){
+ wsdStat.mxValue[op] = wsdStat.nowValue[op];
+ }
+}
+SQLITE_PRIVATE void sqlite3StatusDown(int op, int N){
+ wsdStatInit;
+ assert( N>=0 );
+ assert( op>=0 && op=0 && op=0 );
+ newValue = (sqlite3StatValueType)X;
+ assert( op>=0 && op=0 && opwsdStat.mxValue[op] ){
+ wsdStat.mxValue[op] = newValue;
+ }
+}
+
+/*
+** Query status information.
+*/
+SQLITE_API int sqlite3_status64(
+ int op,
+ sqlite3_int64 *pCurrent,
+ sqlite3_int64 *pHighwater,
+ int resetFlag
+){
+ sqlite3_mutex *pMutex;
+ wsdStatInit;
+ if( op<0 || op>=ArraySize(wsdStat.nowValue) ){
+ return SQLITE_MISUSE_BKPT;
+ }
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT;
+#endif
+ pMutex = statMutex[op] ? sqlite3Pcache1Mutex() : sqlite3MallocMutex();
+ sqlite3_mutex_enter(pMutex);
+ *pCurrent = wsdStat.nowValue[op];
+ *pHighwater = wsdStat.mxValue[op];
+ if( resetFlag ){
+ wsdStat.mxValue[op] = wsdStat.nowValue[op];
+ }
+ sqlite3_mutex_leave(pMutex);
+ (void)pMutex; /* Prevent warning when SQLITE_THREADSAFE=0 */
+ return SQLITE_OK;
+}
+SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){
+ sqlite3_int64 iCur = 0, iHwtr = 0;
+ int rc;
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT;
+#endif
+ rc = sqlite3_status64(op, &iCur, &iHwtr, resetFlag);
+ if( rc==0 ){
+ *pCurrent = (int)iCur;
+ *pHighwater = (int)iHwtr;
+ }
+ return rc;
+}
+
+/*
+** Return the number of LookasideSlot elements on the linked list
+*/
+static u32 countLookasideSlots(LookasideSlot *p){
+ u32 cnt = 0;
+ while( p ){
+ p = p->pNext;
+ cnt++;
+ }
+ return cnt;
+}
+
+/*
+** Count the number of slots of lookaside memory that are outstanding
+*/
+SQLITE_PRIVATE int sqlite3LookasideUsed(sqlite3 *db, int *pHighwater){
+ u32 nInit = countLookasideSlots(db->lookaside.pInit);
+ u32 nFree = countLookasideSlots(db->lookaside.pFree);
+ if( pHighwater ) *pHighwater = db->lookaside.nSlot - nInit;
+ return db->lookaside.nSlot - (nInit+nFree);
+}
+
+/*
+** Query status information for a single database connection
+*/
+SQLITE_API int sqlite3_db_status(
+ sqlite3 *db, /* The database connection whose status is desired */
+ int op, /* Status verb */
+ int *pCurrent, /* Write current value here */
+ int *pHighwater, /* Write high-water mark here */
+ int resetFlag /* Reset high-water mark if true */
+){
+ int rc = SQLITE_OK; /* Return code */
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) || pCurrent==0|| pHighwater==0 ){
+ return SQLITE_MISUSE_BKPT;
+ }
+#endif
+ sqlite3_mutex_enter(db->mutex);
+ switch( op ){
+ case SQLITE_DBSTATUS_LOOKASIDE_USED: {
+ *pCurrent = sqlite3LookasideUsed(db, pHighwater);
+ if( resetFlag ){
+ LookasideSlot *p = db->lookaside.pFree;
+ if( p ){
+ while( p->pNext ) p = p->pNext;
+ p->pNext = db->lookaside.pInit;
+ db->lookaside.pInit = db->lookaside.pFree;
+ db->lookaside.pFree = 0;
+ }
+ }
+ break;
+ }
+
+ case SQLITE_DBSTATUS_LOOKASIDE_HIT:
+ case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE:
+ case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: {
+ testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT );
+ testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE );
+ testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL );
+ assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 );
+ assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 );
+ *pCurrent = 0;
+ *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT];
+ if( resetFlag ){
+ db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0;
+ }
+ break;
+ }
+
+ /*
+ ** Return an approximation for the amount of memory currently used
+ ** by all pagers associated with the given database connection. The
+ ** highwater mark is meaningless and is returned as zero.
+ */
+ case SQLITE_DBSTATUS_CACHE_USED_SHARED:
+ case SQLITE_DBSTATUS_CACHE_USED: {
+ int totalUsed = 0;
+ int i;
+ sqlite3BtreeEnterAll(db);
+ for(i=0; inDb; i++){
+ Btree *pBt = db->aDb[i].pBt;
+ if( pBt ){
+ Pager *pPager = sqlite3BtreePager(pBt);
+ int nByte = sqlite3PagerMemUsed(pPager);
+ if( op==SQLITE_DBSTATUS_CACHE_USED_SHARED ){
+ nByte = nByte / sqlite3BtreeConnectionCount(pBt);
+ }
+ totalUsed += nByte;
+ }
+ }
+ sqlite3BtreeLeaveAll(db);
+ *pCurrent = totalUsed;
+ *pHighwater = 0;
+ break;
+ }
+
+ /*
+ ** *pCurrent gets an accurate estimate of the amount of memory used
+ ** to store the schema for all databases (main, temp, and any ATTACHed
+ ** databases. *pHighwater is set to zero.
+ */
+ case SQLITE_DBSTATUS_SCHEMA_USED: {
+ int i; /* Used to iterate through schemas */
+ int nByte = 0; /* Used to accumulate return value */
+
+ sqlite3BtreeEnterAll(db);
+ db->pnBytesFreed = &nByte;
+ for(i=0; inDb; i++){
+ Schema *pSchema = db->aDb[i].pSchema;
+ if( ALWAYS(pSchema!=0) ){
+ HashElem *p;
+
+ nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
+ pSchema->tblHash.count
+ + pSchema->trigHash.count
+ + pSchema->idxHash.count
+ + pSchema->fkeyHash.count
+ );
+ nByte += sqlite3_msize(pSchema->tblHash.ht);
+ nByte += sqlite3_msize(pSchema->trigHash.ht);
+ nByte += sqlite3_msize(pSchema->idxHash.ht);
+ nByte += sqlite3_msize(pSchema->fkeyHash.ht);
+
+ for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
+ sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
+ }
+ for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
+ sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
+ }
+ }
+ }
+ db->pnBytesFreed = 0;
+ sqlite3BtreeLeaveAll(db);
+
+ *pHighwater = 0;
+ *pCurrent = nByte;
+ break;
+ }
+
+ /*
+ ** *pCurrent gets an accurate estimate of the amount of memory used
+ ** to store all prepared statements.
+ ** *pHighwater is set to zero.
+ */
+ case SQLITE_DBSTATUS_STMT_USED: {
+ struct Vdbe *pVdbe; /* Used to iterate through VMs */
+ int nByte = 0; /* Used to accumulate return value */
+
+ db->pnBytesFreed = &nByte;
+ for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
+ sqlite3VdbeClearObject(db, pVdbe);
+ sqlite3DbFree(db, pVdbe);
+ }
+ db->pnBytesFreed = 0;
+
+ *pHighwater = 0; /* IMP: R-64479-57858 */
+ *pCurrent = nByte;
+
+ break;
+ }
+
+ /*
+ ** Set *pCurrent to the total cache hits or misses encountered by all
+ ** pagers the database handle is connected to. *pHighwater is always set
+ ** to zero.
+ */
+ case SQLITE_DBSTATUS_CACHE_SPILL:
+ op = SQLITE_DBSTATUS_CACHE_WRITE+1;
+ /* Fall through into the next case */
+ case SQLITE_DBSTATUS_CACHE_HIT:
+ case SQLITE_DBSTATUS_CACHE_MISS:
+ case SQLITE_DBSTATUS_CACHE_WRITE:{
+ int i;
+ int nRet = 0;
+ assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 );
+ assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 );
+
+ for(i=0; inDb; i++){
+ if( db->aDb[i].pBt ){
+ Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt);
+ sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet);
+ }
+ }
+ *pHighwater = 0; /* IMP: R-42420-56072 */
+ /* IMP: R-54100-20147 */
+ /* IMP: R-29431-39229 */
+ *pCurrent = nRet;
+ break;
+ }
+
+ /* Set *pCurrent to non-zero if there are unresolved deferred foreign
+ ** key constraints. Set *pCurrent to zero if all foreign key constraints
+ ** have been satisfied. The *pHighwater is always set to zero.
+ */
+ case SQLITE_DBSTATUS_DEFERRED_FKS: {
+ *pHighwater = 0; /* IMP: R-11967-56545 */
+ *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0;
+ break;
+ }
+
+ default: {
+ rc = SQLITE_ERROR;
+ }
+ }
+ sqlite3_mutex_leave(db->mutex);
+ return rc;
+}
+
+/************** End of status.c **********************************************/
+/************** Begin file date.c ********************************************/
+/*
+** 2003 October 31
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement date and time
+** functions for SQLite.
+**
+** There is only one exported symbol in this file - the function
+** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
+** All other code has file scope.
+**
+** SQLite processes all times and dates as julian day numbers. The
+** dates and times are stored as the number of days since noon
+** in Greenwich on November 24, 4714 B.C. according to the Gregorian
+** calendar system.
+**
+** 1970-01-01 00:00:00 is JD 2440587.5
+** 2000-01-01 00:00:00 is JD 2451544.5
+**
+** This implementation requires years to be expressed as a 4-digit number
+** which means that only dates between 0000-01-01 and 9999-12-31 can
+** be represented, even though julian day numbers allow a much wider
+** range of dates.
+**
+** The Gregorian calendar system is used for all dates and times,
+** even those that predate the Gregorian calendar. Historians usually
+** use the julian calendar for dates prior to 1582-10-15 and for some
+** dates afterwards, depending on locale. Beware of this difference.
+**
+** The conversion algorithms are implemented based on descriptions
+** in the following text:
+**
+** Jean Meeus
+** Astronomical Algorithms, 2nd Edition, 1998
+** ISBN 0-943396-61-1
+** Willmann-Bell, Inc
+** Richmond, Virginia (USA)
+*/
+/* #include "sqliteInt.h" */
+/* #include */
+/* #include */
+#include
+
+#ifndef SQLITE_OMIT_DATETIME_FUNCS
+
+/*
+** The MSVC CRT on Windows CE may not have a localtime() function.
+** So declare a substitute. The substitute function itself is
+** defined in "os_win.c".
+*/
+#if !defined(SQLITE_OMIT_LOCALTIME) && defined(_WIN32_WCE) && \
+ (!defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API)
+struct tm *__cdecl localtime(const time_t *);
+#endif
+
+/*
+** A structure for holding a single date and time.
+*/
+typedef struct DateTime DateTime;
+struct DateTime {
+ sqlite3_int64 iJD; /* The julian day number times 86400000 */
+ int Y, M, D; /* Year, month, and day */
+ int h, m; /* Hour and minutes */
+ int tz; /* Timezone offset in minutes */
+ double s; /* Seconds */
+ char validJD; /* True (1) if iJD is valid */
+ char rawS; /* Raw numeric value stored in s */
+ char validYMD; /* True (1) if Y,M,D are valid */
+ char validHMS; /* True (1) if h,m,s are valid */
+ char validTZ; /* True (1) if tz is valid */
+ char tzSet; /* Timezone was set explicitly */
+ char isError; /* An overflow has occurred */
+};
+
+
+/*
+** Convert zDate into one or more integers according to the conversion
+** specifier zFormat.
+**
+** zFormat[] contains 4 characters for each integer converted, except for
+** the last integer which is specified by three characters. The meaning
+** of a four-character format specifiers ABCD is:
+**
+** A: number of digits to convert. Always "2" or "4".
+** B: minimum value. Always "0" or "1".
+** C: maximum value, decoded as:
+** a: 12
+** b: 14
+** c: 24
+** d: 31
+** e: 59
+** f: 9999
+** D: the separator character, or \000 to indicate this is the
+** last number to convert.
+**
+** Example: To translate an ISO-8601 date YYYY-MM-DD, the format would
+** be "40f-21a-20c". The "40f-" indicates the 4-digit year followed by "-".
+** The "21a-" indicates the 2-digit month followed by "-". The "20c" indicates
+** the 2-digit day which is the last integer in the set.
+**
+** The function returns the number of successful conversions.
+*/
+static int getDigits(const char *zDate, const char *zFormat, ...){
+ /* The aMx[] array translates the 3rd character of each format
+ ** spec into a max size: a b c d e f */
+ static const u16 aMx[] = { 12, 14, 24, 31, 59, 9999 };
+ va_list ap;
+ int cnt = 0;
+ char nextC;
+ va_start(ap, zFormat);
+ do{
+ char N = zFormat[0] - '0';
+ char min = zFormat[1] - '0';
+ int val = 0;
+ u16 max;
+
+ assert( zFormat[2]>='a' && zFormat[2]<='f' );
+ max = aMx[zFormat[2] - 'a'];
+ nextC = zFormat[3];
+ val = 0;
+ while( N-- ){
+ if( !sqlite3Isdigit(*zDate) ){
+ goto end_getDigits;
+ }
+ val = val*10 + *zDate - '0';
+ zDate++;
+ }
+ if( val<(int)min || val>(int)max || (nextC!=0 && nextC!=*zDate) ){
+ goto end_getDigits;
+ }
+ *va_arg(ap,int*) = val;
+ zDate++;
+ cnt++;
+ zFormat += 4;
+ }while( nextC );
+end_getDigits:
+ va_end(ap);
+ return cnt;
+}
+
+/*
+** Parse a timezone extension on the end of a date-time.
+** The extension is of the form:
+**
+** (+/-)HH:MM
+**
+** Or the "zulu" notation:
+**
+** Z
+**
+** If the parse is successful, write the number of minutes
+** of change in p->tz and return 0. If a parser error occurs,
+** return non-zero.
+**
+** A missing specifier is not considered an error.
+*/
+static int parseTimezone(const char *zDate, DateTime *p){
+ int sgn = 0;
+ int nHr, nMn;
+ int c;
+ while( sqlite3Isspace(*zDate) ){ zDate++; }
+ p->tz = 0;
+ c = *zDate;
+ if( c=='-' ){
+ sgn = -1;
+ }else if( c=='+' ){
+ sgn = +1;
+ }else if( c=='Z' || c=='z' ){
+ zDate++;
+ goto zulu_time;
+ }else{
+ return c!=0;
+ }
+ zDate++;
+ if( getDigits(zDate, "20b:20e", &nHr, &nMn)!=2 ){
+ return 1;
+ }
+ zDate += 5;
+ p->tz = sgn*(nMn + nHr*60);
+zulu_time:
+ while( sqlite3Isspace(*zDate) ){ zDate++; }
+ p->tzSet = 1;
+ return *zDate!=0;
+}
+
+/*
+** Parse times of the form HH:MM or HH:MM:SS or HH:MM:SS.FFFF.
+** The HH, MM, and SS must each be exactly 2 digits. The
+** fractional seconds FFFF can be one or more digits.
+**
+** Return 1 if there is a parsing error and 0 on success.
+*/
+static int parseHhMmSs(const char *zDate, DateTime *p){
+ int h, m, s;
+ double ms = 0.0;
+ if( getDigits(zDate, "20c:20e", &h, &m)!=2 ){
+ return 1;
+ }
+ zDate += 5;
+ if( *zDate==':' ){
+ zDate++;
+ if( getDigits(zDate, "20e", &s)!=1 ){
+ return 1;
+ }
+ zDate += 2;
+ if( *zDate=='.' && sqlite3Isdigit(zDate[1]) ){
+ double rScale = 1.0;
+ zDate++;
+ while( sqlite3Isdigit(*zDate) ){
+ ms = ms*10.0 + *zDate - '0';
+ rScale *= 10.0;
+ zDate++;
+ }
+ ms /= rScale;
+ }
+ }else{
+ s = 0;
+ }
+ p->validJD = 0;
+ p->rawS = 0;
+ p->validHMS = 1;
+ p->h = h;
+ p->m = m;
+ p->s = s + ms;
+ if( parseTimezone(zDate, p) ) return 1;
+ p->validTZ = (p->tz!=0)?1:0;
+ return 0;
+}
+
+/*
+** Put the DateTime object into its error state.
+*/
+static void datetimeError(DateTime *p){
+ memset(p, 0, sizeof(*p));
+ p->isError = 1;
+}
+
+/*
+** Convert from YYYY-MM-DD HH:MM:SS to julian day. We always assume
+** that the YYYY-MM-DD is according to the Gregorian calendar.
+**
+** Reference: Meeus page 61
+*/
+static void computeJD(DateTime *p){
+ int Y, M, D, A, B, X1, X2;
+
+ if( p->validJD ) return;
+ if( p->validYMD ){
+ Y = p->Y;
+ M = p->M;
+ D = p->D;
+ }else{
+ Y = 2000; /* If no YMD specified, assume 2000-Jan-01 */
+ M = 1;
+ D = 1;
+ }
+ if( Y<-4713 || Y>9999 || p->rawS ){
+ datetimeError(p);
+ return;
+ }
+ if( M<=2 ){
+ Y--;
+ M += 12;
+ }
+ A = Y/100;
+ B = 2 - A + (A/4);
+ X1 = 36525*(Y+4716)/100;
+ X2 = 306001*(M+1)/10000;
+ p->iJD = (sqlite3_int64)((X1 + X2 + D + B - 1524.5 ) * 86400000);
+ p->validJD = 1;
+ if( p->validHMS ){
+ p->iJD += p->h*3600000 + p->m*60000 + (sqlite3_int64)(p->s*1000);
+ if( p->validTZ ){
+ p->iJD -= p->tz*60000;
+ p->validYMD = 0;
+ p->validHMS = 0;
+ p->validTZ = 0;
+ }
+ }
+}
+
+/*
+** Parse dates of the form
+**
+** YYYY-MM-DD HH:MM:SS.FFF
+** YYYY-MM-DD HH:MM:SS
+** YYYY-MM-DD HH:MM
+** YYYY-MM-DD
+**
+** Write the result into the DateTime structure and return 0
+** on success and 1 if the input string is not a well-formed
+** date.
+*/
+static int parseYyyyMmDd(const char *zDate, DateTime *p){
+ int Y, M, D, neg;
+
+ if( zDate[0]=='-' ){
+ zDate++;
+ neg = 1;
+ }else{
+ neg = 0;
+ }
+ if( getDigits(zDate, "40f-21a-21d", &Y, &M, &D)!=3 ){
+ return 1;
+ }
+ zDate += 10;
+ while( sqlite3Isspace(*zDate) || 'T'==*(u8*)zDate ){ zDate++; }
+ if( parseHhMmSs(zDate, p)==0 ){
+ /* We got the time */
+ }else if( *zDate==0 ){
+ p->validHMS = 0;
+ }else{
+ return 1;
+ }
+ p->validJD = 0;
+ p->validYMD = 1;
+ p->Y = neg ? -Y : Y;
+ p->M = M;
+ p->D = D;
+ if( p->validTZ ){
+ computeJD(p);
+ }
+ return 0;
+}
+
+/*
+** Set the time to the current time reported by the VFS.
+**
+** Return the number of errors.
+*/
+static int setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
+ p->iJD = sqlite3StmtCurrentTime(context);
+ if( p->iJD>0 ){
+ p->validJD = 1;
+ return 0;
+ }else{
+ return 1;
+ }
+}
+
+/*
+** Input "r" is a numeric quantity which might be a julian day number,
+** or the number of seconds since 1970. If the value if r is within
+** range of a julian day number, install it as such and set validJD.
+** If the value is a valid unix timestamp, put it in p->s and set p->rawS.
+*/
+static void setRawDateNumber(DateTime *p, double r){
+ p->s = r;
+ p->rawS = 1;
+ if( r>=0.0 && r<5373484.5 ){
+ p->iJD = (sqlite3_int64)(r*86400000.0 + 0.5);
+ p->validJD = 1;
+ }
+}
+
+/*
+** Attempt to parse the given string into a julian day number. Return
+** the number of errors.
+**
+** The following are acceptable forms for the input string:
+**
+** YYYY-MM-DD HH:MM:SS.FFF +/-HH:MM
+** DDDD.DD
+** now
+**
+** In the first form, the +/-HH:MM is always optional. The fractional
+** seconds extension (the ".FFF") is optional. The seconds portion
+** (":SS.FFF") is option. The year and date can be omitted as long
+** as there is a time string. The time string can be omitted as long
+** as there is a year and date.
+*/
+static int parseDateOrTime(
+ sqlite3_context *context,
+ const char *zDate,
+ DateTime *p
+){
+ double r;
+ if( parseYyyyMmDd(zDate,p)==0 ){
+ return 0;
+ }else if( parseHhMmSs(zDate, p)==0 ){
+ return 0;
+ }else if( sqlite3StrICmp(zDate,"now")==0 && sqlite3NotPureFunc(context) ){
+ return setDateTimeToCurrent(context, p);
+ }else if( sqlite3AtoF(zDate, &r, sqlite3Strlen30(zDate), SQLITE_UTF8) ){
+ setRawDateNumber(p, r);
+ return 0;
+ }
+ return 1;
+}
+
+/* The julian day number for 9999-12-31 23:59:59.999 is 5373484.4999999.
+** Multiplying this by 86400000 gives 464269060799999 as the maximum value
+** for DateTime.iJD.
+**
+** But some older compilers (ex: gcc 4.2.1 on older Macs) cannot deal with
+** such a large integer literal, so we have to encode it.
+*/
+#define INT_464269060799999 ((((i64)0x1a640)<<32)|0x1072fdff)
+
+/*
+** Return TRUE if the given julian day number is within range.
+**
+** The input is the JulianDay times 86400000.
+*/
+static int validJulianDay(sqlite3_int64 iJD){
+ return iJD>=0 && iJD<=INT_464269060799999;
+}
+
+/*
+** Compute the Year, Month, and Day from the julian day number.
+*/
+static void computeYMD(DateTime *p){
+ int Z, A, B, C, D, E, X1;
+ if( p->validYMD ) return;
+ if( !p->validJD ){
+ p->Y = 2000;
+ p->M = 1;
+ p->D = 1;
+ }else if( !validJulianDay(p->iJD) ){
+ datetimeError(p);
+ return;
+ }else{
+ Z = (int)((p->iJD + 43200000)/86400000);
+ A = (int)((Z - 1867216.25)/36524.25);
+ A = Z + 1 + A - (A/4);
+ B = A + 1524;
+ C = (int)((B - 122.1)/365.25);
+ D = (36525*(C&32767))/100;
+ E = (int)((B-D)/30.6001);
+ X1 = (int)(30.6001*E);
+ p->D = B - D - X1;
+ p->M = E<14 ? E-1 : E-13;
+ p->Y = p->M>2 ? C - 4716 : C - 4715;
+ }
+ p->validYMD = 1;
+}
+
+/*
+** Compute the Hour, Minute, and Seconds from the julian day number.
+*/
+static void computeHMS(DateTime *p){
+ int s;
+ if( p->validHMS ) return;
+ computeJD(p);
+ s = (int)((p->iJD + 43200000) % 86400000);
+ p->s = s/1000.0;
+ s = (int)p->s;
+ p->s -= s;
+ p->h = s/3600;
+ s -= p->h*3600;
+ p->m = s/60;
+ p->s += s - p->m*60;
+ p->rawS = 0;
+ p->validHMS = 1;
+}
+
+/*
+** Compute both YMD and HMS
+*/
+static void computeYMD_HMS(DateTime *p){
+ computeYMD(p);
+ computeHMS(p);
+}
+
+/*
+** Clear the YMD and HMS and the TZ
+*/
+static void clearYMD_HMS_TZ(DateTime *p){
+ p->validYMD = 0;
+ p->validHMS = 0;
+ p->validTZ = 0;
+}
+
+#ifndef SQLITE_OMIT_LOCALTIME
+/*
+** On recent Windows platforms, the localtime_s() function is available
+** as part of the "Secure CRT". It is essentially equivalent to
+** localtime_r() available under most POSIX platforms, except that the
+** order of the parameters is reversed.
+**
+** See http://msdn.microsoft.com/en-us/library/a442x3ye(VS.80).aspx.
+**
+** If the user has not indicated to use localtime_r() or localtime_s()
+** already, check for an MSVC build environment that provides
+** localtime_s().
+*/
+#if !HAVE_LOCALTIME_R && !HAVE_LOCALTIME_S \
+ && defined(_MSC_VER) && defined(_CRT_INSECURE_DEPRECATE)
+#undef HAVE_LOCALTIME_S
+#define HAVE_LOCALTIME_S 1
+#endif
+
+/*
+** The following routine implements the rough equivalent of localtime_r()
+** using whatever operating-system specific localtime facility that
+** is available. This routine returns 0 on success and
+** non-zero on any kind of error.
+**
+** If the sqlite3GlobalConfig.bLocaltimeFault variable is true then this
+** routine will always fail.
+**
+** EVIDENCE-OF: R-62172-00036 In this implementation, the standard C
+** library function localtime_r() is used to assist in the calculation of
+** local time.
+*/
+static int osLocaltime(time_t *t, struct tm *pTm){
+ int rc;
+#if !HAVE_LOCALTIME_R && !HAVE_LOCALTIME_S
+ struct tm *pX;
+#if SQLITE_THREADSAFE>0
+ sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+ sqlite3_mutex_enter(mutex);
+ pX = localtime(t);
+#ifndef SQLITE_UNTESTABLE
+ if( sqlite3GlobalConfig.bLocaltimeFault ) pX = 0;
+#endif
+ if( pX ) *pTm = *pX;
+ sqlite3_mutex_leave(mutex);
+ rc = pX==0;
+#else
+#ifndef SQLITE_UNTESTABLE
+ if( sqlite3GlobalConfig.bLocaltimeFault ) return 1;
+#endif
+#if HAVE_LOCALTIME_R
+ rc = localtime_r(t, pTm)==0;
+#else
+ rc = localtime_s(pTm, t);
+#endif /* HAVE_LOCALTIME_R */
+#endif /* HAVE_LOCALTIME_R || HAVE_LOCALTIME_S */
+ return rc;
+}
+#endif /* SQLITE_OMIT_LOCALTIME */
+
+
+#ifndef SQLITE_OMIT_LOCALTIME
+/*
+** Compute the difference (in milliseconds) between localtime and UTC
+** (a.k.a. GMT) for the time value p where p is in UTC. If no error occurs,
+** return this value and set *pRc to SQLITE_OK.
+**
+** Or, if an error does occur, set *pRc to SQLITE_ERROR. The returned value
+** is undefined in this case.
+*/
+static sqlite3_int64 localtimeOffset(
+ DateTime *p, /* Date at which to calculate offset */
+ sqlite3_context *pCtx, /* Write error here if one occurs */
+ int *pRc /* OUT: Error code. SQLITE_OK or ERROR */
+){
+ DateTime x, y;
+ time_t t;
+ struct tm sLocal;
+
+ /* Initialize the contents of sLocal to avoid a compiler warning. */
+ memset(&sLocal, 0, sizeof(sLocal));
+
+ x = *p;
+ computeYMD_HMS(&x);
+ if( x.Y<1971 || x.Y>=2038 ){
+ /* EVIDENCE-OF: R-55269-29598 The localtime_r() C function normally only
+ ** works for years between 1970 and 2037. For dates outside this range,
+ ** SQLite attempts to map the year into an equivalent year within this
+ ** range, do the calculation, then map the year back.
+ */
+ x.Y = 2000;
+ x.M = 1;
+ x.D = 1;
+ x.h = 0;
+ x.m = 0;
+ x.s = 0.0;
+ } else {
+ int s = (int)(x.s + 0.5);
+ x.s = s;
+ }
+ x.tz = 0;
+ x.validJD = 0;
+ computeJD(&x);
+ t = (time_t)(x.iJD/1000 - 21086676*(i64)10000);
+ if( osLocaltime(&t, &sLocal) ){
+ sqlite3_result_error(pCtx, "local time unavailable", -1);
+ *pRc = SQLITE_ERROR;
+ return 0;
+ }
+ y.Y = sLocal.tm_year + 1900;
+ y.M = sLocal.tm_mon + 1;
+ y.D = sLocal.tm_mday;
+ y.h = sLocal.tm_hour;
+ y.m = sLocal.tm_min;
+ y.s = sLocal.tm_sec;
+ y.validYMD = 1;
+ y.validHMS = 1;
+ y.validJD = 0;
+ y.rawS = 0;
+ y.validTZ = 0;
+ y.isError = 0;
+ computeJD(&y);
+ *pRc = SQLITE_OK;
+ return y.iJD - x.iJD;
+}
+#endif /* SQLITE_OMIT_LOCALTIME */
+
+/*
+** The following table defines various date transformations of the form
+**
+** 'NNN days'
+**
+** Where NNN is an arbitrary floating-point number and "days" can be one
+** of several units of time.
+*/
+static const struct {
+ u8 eType; /* Transformation type code */
+ u8 nName; /* Length of th name */
+ char *zName; /* Name of the transformation */
+ double rLimit; /* Maximum NNN value for this transform */
+ double rXform; /* Constant used for this transform */
+} aXformType[] = {
+ { 0, 6, "second", 464269060800.0, 86400000.0/(24.0*60.0*60.0) },
+ { 0, 6, "minute", 7737817680.0, 86400000.0/(24.0*60.0) },
+ { 0, 4, "hour", 128963628.0, 86400000.0/24.0 },
+ { 0, 3, "day", 5373485.0, 86400000.0 },
+ { 1, 5, "month", 176546.0, 30.0*86400000.0 },
+ { 2, 4, "year", 14713.0, 365.0*86400000.0 },
+};
+
+/*
+** Process a modifier to a date-time stamp. The modifiers are
+** as follows:
+**
+** NNN days
+** NNN hours
+** NNN minutes
+** NNN.NNNN seconds
+** NNN months
+** NNN years
+** start of month
+** start of year
+** start of week
+** start of day
+** weekday N
+** unixepoch
+** localtime
+** utc
+**
+** Return 0 on success and 1 if there is any kind of error. If the error
+** is in a system call (i.e. localtime()), then an error message is written
+** to context pCtx. If the error is an unrecognized modifier, no error is
+** written to pCtx.
+*/
+static int parseModifier(
+ sqlite3_context *pCtx, /* Function context */
+ const char *z, /* The text of the modifier */
+ int n, /* Length of zMod in bytes */
+ DateTime *p /* The date/time value to be modified */
+){
+ int rc = 1;
+ double r;
+ switch(sqlite3UpperToLower[(u8)z[0]] ){
+#ifndef SQLITE_OMIT_LOCALTIME
+ case 'l': {
+ /* localtime
+ **
+ ** Assuming the current time value is UTC (a.k.a. GMT), shift it to
+ ** show local time.
+ */
+ if( sqlite3_stricmp(z, "localtime")==0 && sqlite3NotPureFunc(pCtx) ){
+ computeJD(p);
+ p->iJD += localtimeOffset(p, pCtx, &rc);
+ clearYMD_HMS_TZ(p);
+ }
+ break;
+ }
+#endif
+ case 'u': {
+ /*
+ ** unixepoch
+ **
+ ** Treat the current value of p->s as the number of
+ ** seconds since 1970. Convert to a real julian day number.
+ */
+ if( sqlite3_stricmp(z, "unixepoch")==0 && p->rawS ){
+ r = p->s*1000.0 + 210866760000000.0;
+ if( r>=0.0 && r<464269060800000.0 ){
+ clearYMD_HMS_TZ(p);
+ p->iJD = (sqlite3_int64)r;
+ p->validJD = 1;
+ p->rawS = 0;
+ rc = 0;
+ }
+ }
+#ifndef SQLITE_OMIT_LOCALTIME
+ else if( sqlite3_stricmp(z, "utc")==0 && sqlite3NotPureFunc(pCtx) ){
+ if( p->tzSet==0 ){
+ sqlite3_int64 c1;
+ computeJD(p);
+ c1 = localtimeOffset(p, pCtx, &rc);
+ if( rc==SQLITE_OK ){
+ p->iJD -= c1;
+ clearYMD_HMS_TZ(p);
+ p->iJD += c1 - localtimeOffset(p, pCtx, &rc);
+ }
+ p->tzSet = 1;
+ }else{
+ rc = SQLITE_OK;
+ }
+ }
+#endif
+ break;
+ }
+ case 'w': {
+ /*
+ ** weekday N
+ **
+ ** Move the date to the same time on the next occurrence of
+ ** weekday N where 0==Sunday, 1==Monday, and so forth. If the
+ ** date is already on the appropriate weekday, this is a no-op.
+ */
+ if( sqlite3_strnicmp(z, "weekday ", 8)==0
+ && sqlite3AtoF(&z[8], &r, sqlite3Strlen30(&z[8]), SQLITE_UTF8)
+ && (n=(int)r)==r && n>=0 && r<7 ){
+ sqlite3_int64 Z;
+ computeYMD_HMS(p);
+ p->validTZ = 0;
+ p->validJD = 0;
+ computeJD(p);
+ Z = ((p->iJD + 129600000)/86400000) % 7;
+ if( Z>n ) Z -= 7;
+ p->iJD += (n - Z)*86400000;
+ clearYMD_HMS_TZ(p);
+ rc = 0;
+ }
+ break;
+ }
+ case 's': {
+ /*
+ ** start of TTTTT
+ **
+ ** Move the date backwards to the beginning of the current day,
+ ** or month or year.
+ */
+ if( sqlite3_strnicmp(z, "start of ", 9)!=0 ) break;
+ if( !p->validJD && !p->validYMD && !p->validHMS ) break;
+ z += 9;
+ computeYMD(p);
+ p->validHMS = 1;
+ p->h = p->m = 0;
+ p->s = 0.0;
+ p->rawS = 0;
+ p->validTZ = 0;
+ p->validJD = 0;
+ if( sqlite3_stricmp(z,"month")==0 ){
+ p->D = 1;
+ rc = 0;
+ }else if( sqlite3_stricmp(z,"year")==0 ){
+ p->M = 1;
+ p->D = 1;
+ rc = 0;
+ }else if( sqlite3_stricmp(z,"day")==0 ){
+ rc = 0;
+ }
+ break;
+ }
+ case '+':
+ case '-':
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9': {
+ double rRounder;
+ int i;
+ for(n=1; z[n] && z[n]!=':' && !sqlite3Isspace(z[n]); n++){}
+ if( !sqlite3AtoF(z, &r, n, SQLITE_UTF8) ){
+ rc = 1;
+ break;
+ }
+ if( z[n]==':' ){
+ /* A modifier of the form (+|-)HH:MM:SS.FFF adds (or subtracts) the
+ ** specified number of hours, minutes, seconds, and fractional seconds
+ ** to the time. The ".FFF" may be omitted. The ":SS.FFF" may be
+ ** omitted.
+ */
+ const char *z2 = z;
+ DateTime tx;
+ sqlite3_int64 day;
+ if( !sqlite3Isdigit(*z2) ) z2++;
+ memset(&tx, 0, sizeof(tx));
+ if( parseHhMmSs(z2, &tx) ) break;
+ computeJD(&tx);
+ tx.iJD -= 43200000;
+ day = tx.iJD/86400000;
+ tx.iJD -= day*86400000;
+ if( z[0]=='-' ) tx.iJD = -tx.iJD;
+ computeJD(p);
+ clearYMD_HMS_TZ(p);
+ p->iJD += tx.iJD;
+ rc = 0;
+ break;
+ }
+
+ /* If control reaches this point, it means the transformation is
+ ** one of the forms like "+NNN days". */
+ z += n;
+ while( sqlite3Isspace(*z) ) z++;
+ n = sqlite3Strlen30(z);
+ if( n>10 || n<3 ) break;
+ if( sqlite3UpperToLower[(u8)z[n-1]]=='s' ) n--;
+ computeJD(p);
+ rc = 1;
+ rRounder = r<0 ? -0.5 : +0.5;
+ for(i=0; i-aXformType[i].rLimit && rM += (int)r;
+ x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
+ p->Y += x;
+ p->M -= x*12;
+ p->validJD = 0;
+ r -= (int)r;
+ break;
+ }
+ case 2: { /* Special processing to add years */
+ int y = (int)r;
+ computeYMD_HMS(p);
+ p->Y += y;
+ p->validJD = 0;
+ r -= (int)r;
+ break;
+ }
+ }
+ computeJD(p);
+ p->iJD += (sqlite3_int64)(r*aXformType[i].rXform + rRounder);
+ rc = 0;
+ break;
+ }
+ }
+ clearYMD_HMS_TZ(p);
+ break;
+ }
+ default: {
+ break;
+ }
+ }
+ return rc;
+}
+
+/*
+** Process time function arguments. argv[0] is a date-time stamp.
+** argv[1] and following are modifiers. Parse them all and write
+** the resulting time into the DateTime structure p. Return 0
+** on success and 1 if there are any errors.
+**
+** If there are zero parameters (if even argv[0] is undefined)
+** then assume a default value of "now" for argv[0].
+*/
+static int isDate(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv,
+ DateTime *p
+){
+ int i, n;
+ const unsigned char *z;
+ int eType;
+ memset(p, 0, sizeof(*p));
+ if( argc==0 ){
+ return setDateTimeToCurrent(context, p);
+ }
+ if( (eType = sqlite3_value_type(argv[0]))==SQLITE_FLOAT
+ || eType==SQLITE_INTEGER ){
+ setRawDateNumber(p, sqlite3_value_double(argv[0]));
+ }else{
+ z = sqlite3_value_text(argv[0]);
+ if( !z || parseDateOrTime(context, (char*)z, p) ){
+ return 1;
+ }
+ }
+ for(i=1; iisError || !validJulianDay(p->iJD) ) return 1;
+ return 0;
+}
+
+
+/*
+** The following routines implement the various date and time functions
+** of SQLite.
+*/
+
+/*
+** julianday( TIMESTRING, MOD, MOD, ...)
+**
+** Return the julian day number of the date specified in the arguments
+*/
+static void juliandayFunc(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv
+){
+ DateTime x;
+ if( isDate(context, argc, argv, &x)==0 ){
+ computeJD(&x);
+ sqlite3_result_double(context, x.iJD/86400000.0);
+ }
+}
+
+/*
+** datetime( TIMESTRING, MOD, MOD, ...)
+**
+** Return YYYY-MM-DD HH:MM:SS
+*/
+static void datetimeFunc(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv
+){
+ DateTime x;
+ if( isDate(context, argc, argv, &x)==0 ){
+ char zBuf[100];
+ computeYMD_HMS(&x);
+ sqlite3_snprintf(sizeof(zBuf), zBuf, "%04d-%02d-%02d %02d:%02d:%02d",
+ x.Y, x.M, x.D, x.h, x.m, (int)(x.s));
+ sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
+ }
+}
+
+/*
+** time( TIMESTRING, MOD, MOD, ...)
+**
+** Return HH:MM:SS
+*/
+static void timeFunc(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv
+){
+ DateTime x;
+ if( isDate(context, argc, argv, &x)==0 ){
+ char zBuf[100];
+ computeHMS(&x);
+ sqlite3_snprintf(sizeof(zBuf), zBuf, "%02d:%02d:%02d", x.h, x.m, (int)x.s);
+ sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
+ }
+}
+
+/*
+** date( TIMESTRING, MOD, MOD, ...)
+**
+** Return YYYY-MM-DD
+*/
+static void dateFunc(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv
+){
+ DateTime x;
+ if( isDate(context, argc, argv, &x)==0 ){
+ char zBuf[100];
+ computeYMD(&x);
+ sqlite3_snprintf(sizeof(zBuf), zBuf, "%04d-%02d-%02d", x.Y, x.M, x.D);
+ sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
+ }
+}
+
+/*
+** strftime( FORMAT, TIMESTRING, MOD, MOD, ...)
+**
+** Return a string described by FORMAT. Conversions as follows:
+**
+** %d day of month
+** %f ** fractional seconds SS.SSS
+** %H hour 00-24
+** %j day of year 000-366
+** %J ** julian day number
+** %m month 01-12
+** %M minute 00-59
+** %s seconds since 1970-01-01
+** %S seconds 00-59
+** %w day of week 0-6 sunday==0
+** %W week of year 00-53
+** %Y year 0000-9999
+** %% %
+*/
+static void strftimeFunc(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv
+){
+ DateTime x;
+ u64 n;
+ size_t i,j;
+ char *z;
+ sqlite3 *db;
+ const char *zFmt;
+ char zBuf[100];
+ if( argc==0 ) return;
+ zFmt = (const char*)sqlite3_value_text(argv[0]);
+ if( zFmt==0 || isDate(context, argc-1, argv+1, &x) ) return;
+ db = sqlite3_context_db_handle(context);
+ for(i=0, n=1; zFmt[i]; i++, n++){
+ if( zFmt[i]=='%' ){
+ switch( zFmt[i+1] ){
+ case 'd':
+ case 'H':
+ case 'm':
+ case 'M':
+ case 'S':
+ case 'W':
+ n++;
+ /* fall thru */
+ case 'w':
+ case '%':
+ break;
+ case 'f':
+ n += 8;
+ break;
+ case 'j':
+ n += 3;
+ break;
+ case 'Y':
+ n += 8;
+ break;
+ case 's':
+ case 'J':
+ n += 50;
+ break;
+ default:
+ return; /* ERROR. return a NULL */
+ }
+ i++;
+ }
+ }
+ testcase( n==sizeof(zBuf)-1 );
+ testcase( n==sizeof(zBuf) );
+ testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH]+1 );
+ testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH] );
+ if( n(u64)db->aLimit[SQLITE_LIMIT_LENGTH] ){
+ sqlite3_result_error_toobig(context);
+ return;
+ }else{
+ z = sqlite3DbMallocRawNN(db, (int)n);
+ if( z==0 ){
+ sqlite3_result_error_nomem(context);
+ return;
+ }
+ }
+ computeJD(&x);
+ computeYMD_HMS(&x);
+ for(i=j=0; zFmt[i]; i++){
+ if( zFmt[i]!='%' ){
+ z[j++] = zFmt[i];
+ }else{
+ i++;
+ switch( zFmt[i] ){
+ case 'd': sqlite3_snprintf(3, &z[j],"%02d",x.D); j+=2; break;
+ case 'f': {
+ double s = x.s;
+ if( s>59.999 ) s = 59.999;
+ sqlite3_snprintf(7, &z[j],"%06.3f", s);
+ j += sqlite3Strlen30(&z[j]);
+ break;
+ }
+ case 'H': sqlite3_snprintf(3, &z[j],"%02d",x.h); j+=2; break;
+ case 'W': /* Fall thru */
+ case 'j': {
+ int nDay; /* Number of days since 1st day of year */
+ DateTime y = x;
+ y.validJD = 0;
+ y.M = 1;
+ y.D = 1;
+ computeJD(&y);
+ nDay = (int)((x.iJD-y.iJD+43200000)/86400000);
+ if( zFmt[i]=='W' ){
+ int wd; /* 0=Monday, 1=Tuesday, ... 6=Sunday */
+ wd = (int)(((x.iJD+43200000)/86400000)%7);
+ sqlite3_snprintf(3, &z[j],"%02d",(nDay+7-wd)/7);
+ j += 2;
+ }else{
+ sqlite3_snprintf(4, &z[j],"%03d",nDay+1);
+ j += 3;
+ }
+ break;
+ }
+ case 'J': {
+ sqlite3_snprintf(20, &z[j],"%.16g",x.iJD/86400000.0);
+ j+=sqlite3Strlen30(&z[j]);
+ break;
+ }
+ case 'm': sqlite3_snprintf(3, &z[j],"%02d",x.M); j+=2; break;
+ case 'M': sqlite3_snprintf(3, &z[j],"%02d",x.m); j+=2; break;
+ case 's': {
+ sqlite3_snprintf(30,&z[j],"%lld",
+ (i64)(x.iJD/1000 - 21086676*(i64)10000));
+ j += sqlite3Strlen30(&z[j]);
+ break;
+ }
+ case 'S': sqlite3_snprintf(3,&z[j],"%02d",(int)x.s); j+=2; break;
+ case 'w': {
+ z[j++] = (char)(((x.iJD+129600000)/86400000) % 7) + '0';
+ break;
+ }
+ case 'Y': {
+ sqlite3_snprintf(5,&z[j],"%04d",x.Y); j+=sqlite3Strlen30(&z[j]);
+ break;
+ }
+ default: z[j++] = '%'; break;
+ }
+ }
+ }
+ z[j] = 0;
+ sqlite3_result_text(context, z, -1,
+ z==zBuf ? SQLITE_TRANSIENT : SQLITE_DYNAMIC);
+}
+
+/*
+** current_time()
+**
+** This function returns the same value as time('now').
+*/
+static void ctimeFunc(
+ sqlite3_context *context,
+ int NotUsed,
+ sqlite3_value **NotUsed2
+){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ timeFunc(context, 0, 0);
+}
+
+/*
+** current_date()
+**
+** This function returns the same value as date('now').
+*/
+static void cdateFunc(
+ sqlite3_context *context,
+ int NotUsed,
+ sqlite3_value **NotUsed2
+){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ dateFunc(context, 0, 0);
+}
+
+/*
+** current_timestamp()
+**
+** This function returns the same value as datetime('now').
+*/
+static void ctimestampFunc(
+ sqlite3_context *context,
+ int NotUsed,
+ sqlite3_value **NotUsed2
+){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ datetimeFunc(context, 0, 0);
+}
+#endif /* !defined(SQLITE_OMIT_DATETIME_FUNCS) */
+
+#ifdef SQLITE_OMIT_DATETIME_FUNCS
+/*
+** If the library is compiled to omit the full-scale date and time
+** handling (to get a smaller binary), the following minimal version
+** of the functions current_time(), current_date() and current_timestamp()
+** are included instead. This is to support column declarations that
+** include "DEFAULT CURRENT_TIME" etc.
+**
+** This function uses the C-library functions time(), gmtime()
+** and strftime(). The format string to pass to strftime() is supplied
+** as the user-data for the function.
+*/
+static void currentTimeFunc(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv
+){
+ time_t t;
+ char *zFormat = (char *)sqlite3_user_data(context);
+ sqlite3_int64 iT;
+ struct tm *pTm;
+ struct tm sNow;
+ char zBuf[20];
+
+ UNUSED_PARAMETER(argc);
+ UNUSED_PARAMETER(argv);
+
+ iT = sqlite3StmtCurrentTime(context);
+ if( iT<=0 ) return;
+ t = iT/1000 - 10000*(sqlite3_int64)21086676;
+#if HAVE_GMTIME_R
+ pTm = gmtime_r(&t, &sNow);
+#else
+ sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+ pTm = gmtime(&t);
+ if( pTm ) memcpy(&sNow, pTm, sizeof(sNow));
+ sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+#endif
+ if( pTm ){
+ strftime(zBuf, 20, zFormat, &sNow);
+ sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
+ }
+}
+#endif
+
+/*
+** This function registered all of the above C functions as SQL
+** functions. This should be the only routine in this file with
+** external linkage.
+*/
+SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(void){
+ static FuncDef aDateTimeFuncs[] = {
+#ifndef SQLITE_OMIT_DATETIME_FUNCS
+ PURE_DATE(julianday, -1, 0, 0, juliandayFunc ),
+ PURE_DATE(date, -1, 0, 0, dateFunc ),
+ PURE_DATE(time, -1, 0, 0, timeFunc ),
+ PURE_DATE(datetime, -1, 0, 0, datetimeFunc ),
+ PURE_DATE(strftime, -1, 0, 0, strftimeFunc ),
+ DFUNCTION(current_time, 0, 0, 0, ctimeFunc ),
+ DFUNCTION(current_timestamp, 0, 0, 0, ctimestampFunc),
+ DFUNCTION(current_date, 0, 0, 0, cdateFunc ),
+#else
+ STR_FUNCTION(current_time, 0, "%H:%M:%S", 0, currentTimeFunc),
+ STR_FUNCTION(current_date, 0, "%Y-%m-%d", 0, currentTimeFunc),
+ STR_FUNCTION(current_timestamp, 0, "%Y-%m-%d %H:%M:%S", 0, currentTimeFunc),
+#endif
+ };
+ sqlite3InsertBuiltinFuncs(aDateTimeFuncs, ArraySize(aDateTimeFuncs));
+}
+
+/************** End of date.c ************************************************/
+/************** Begin file os.c **********************************************/
+/*
+** 2005 November 29
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains OS interface code that is common to all
+** architectures.
+*/
+/* #include "sqliteInt.h" */
+
+/*
+** If we compile with the SQLITE_TEST macro set, then the following block
+** of code will give us the ability to simulate a disk I/O error. This
+** is used for testing the I/O recovery logic.
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API int sqlite3_io_error_hit = 0; /* Total number of I/O Errors */
+SQLITE_API int sqlite3_io_error_hardhit = 0; /* Number of non-benign errors */
+SQLITE_API int sqlite3_io_error_pending = 0; /* Count down to first I/O error */
+SQLITE_API int sqlite3_io_error_persist = 0; /* True if I/O errors persist */
+SQLITE_API int sqlite3_io_error_benign = 0; /* True if errors are benign */
+SQLITE_API int sqlite3_diskfull_pending = 0;
+SQLITE_API int sqlite3_diskfull = 0;
+#endif /* defined(SQLITE_TEST) */
+
+/*
+** When testing, also keep a count of the number of open files.
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API int sqlite3_open_file_count = 0;
+#endif /* defined(SQLITE_TEST) */
+
+/*
+** The default SQLite sqlite3_vfs implementations do not allocate
+** memory (actually, os_unix.c allocates a small amount of memory
+** from within OsOpen()), but some third-party implementations may.
+** So we test the effects of a malloc() failing and the sqlite3OsXXX()
+** function returning SQLITE_IOERR_NOMEM using the DO_OS_MALLOC_TEST macro.
+**
+** The following functions are instrumented for malloc() failure
+** testing:
+**
+** sqlite3OsRead()
+** sqlite3OsWrite()
+** sqlite3OsSync()
+** sqlite3OsFileSize()
+** sqlite3OsLock()
+** sqlite3OsCheckReservedLock()
+** sqlite3OsFileControl()
+** sqlite3OsShmMap()
+** sqlite3OsOpen()
+** sqlite3OsDelete()
+** sqlite3OsAccess()
+** sqlite3OsFullPathname()
+**
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API int sqlite3_memdebug_vfs_oom_test = 1;
+ #define DO_OS_MALLOC_TEST(x) \
+ if (sqlite3_memdebug_vfs_oom_test && (!x || !sqlite3JournalIsInMemory(x))) { \
+ void *pTstAlloc = sqlite3Malloc(10); \
+ if (!pTstAlloc) return SQLITE_IOERR_NOMEM_BKPT; \
+ sqlite3_free(pTstAlloc); \
+ }
+#else
+ #define DO_OS_MALLOC_TEST(x)
+#endif
+
+/*
+** The following routines are convenience wrappers around methods
+** of the sqlite3_file object. This is mostly just syntactic sugar. All
+** of this would be completely automatic if SQLite were coded using
+** C++ instead of plain old C.
+*/
+SQLITE_PRIVATE void sqlite3OsClose(sqlite3_file *pId){
+ if( pId->pMethods ){
+ pId->pMethods->xClose(pId);
+ pId->pMethods = 0;
+ }
+}
+SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file *id, void *pBuf, int amt, i64 offset){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xRead(id, pBuf, amt, offset);
+}
+SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file *id, const void *pBuf, int amt, i64 offset){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xWrite(id, pBuf, amt, offset);
+}
+SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file *id, i64 size){
+ return id->pMethods->xTruncate(id, size);
+}
+SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file *id, int flags){
+ DO_OS_MALLOC_TEST(id);
+ return flags ? id->pMethods->xSync(id, flags) : SQLITE_OK;
+}
+SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file *id, i64 *pSize){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xFileSize(id, pSize);
+}
+SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file *id, int lockType){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xLock(id, lockType);
+}
+SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file *id, int lockType){
+ return id->pMethods->xUnlock(id, lockType);
+}
+SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xCheckReservedLock(id, pResOut);
+}
+
+/*
+** Use sqlite3OsFileControl() when we are doing something that might fail
+** and we need to know about the failures. Use sqlite3OsFileControlHint()
+** when simply tossing information over the wall to the VFS and we do not
+** really care if the VFS receives and understands the information since it
+** is only a hint and can be safely ignored. The sqlite3OsFileControlHint()
+** routine has no return value since the return value would be meaningless.
+*/
+SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file *id, int op, void *pArg){
+ if( id->pMethods==0 ) return SQLITE_NOTFOUND;
+#ifdef SQLITE_TEST
+ if( op!=SQLITE_FCNTL_COMMIT_PHASETWO
+ && op!=SQLITE_FCNTL_LOCK_TIMEOUT
+ ){
+ /* Faults are not injected into COMMIT_PHASETWO because, assuming SQLite
+ ** is using a regular VFS, it is called after the corresponding
+ ** transaction has been committed. Injecting a fault at this point
+ ** confuses the test scripts - the COMMIT comand returns SQLITE_NOMEM
+ ** but the transaction is committed anyway.
+ **
+ ** The core must call OsFileControl() though, not OsFileControlHint(),
+ ** as if a custom VFS (e.g. zipvfs) returns an error here, it probably
+ ** means the commit really has failed and an error should be returned
+ ** to the user. */
+ DO_OS_MALLOC_TEST(id);
+ }
+#endif
+ return id->pMethods->xFileControl(id, op, pArg);
+}
+SQLITE_PRIVATE void sqlite3OsFileControlHint(sqlite3_file *id, int op, void *pArg){
+ if( id->pMethods ) (void)id->pMethods->xFileControl(id, op, pArg);
+}
+
+SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id){
+ int (*xSectorSize)(sqlite3_file*) = id->pMethods->xSectorSize;
+ return (xSectorSize ? xSectorSize(id) : SQLITE_DEFAULT_SECTOR_SIZE);
+}
+SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id){
+ return id->pMethods->xDeviceCharacteristics(id);
+}
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int offset, int n, int flags){
+ return id->pMethods->xShmLock(id, offset, n, flags);
+}
+SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id){
+ id->pMethods->xShmBarrier(id);
+}
+SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int deleteFlag){
+ return id->pMethods->xShmUnmap(id, deleteFlag);
+}
+SQLITE_PRIVATE int sqlite3OsShmMap(
+ sqlite3_file *id, /* Database file handle */
+ int iPage,
+ int pgsz,
+ int bExtend, /* True to extend file if necessary */
+ void volatile **pp /* OUT: Pointer to mapping */
+){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xShmMap(id, iPage, pgsz, bExtend, pp);
+}
+#endif /* SQLITE_OMIT_WAL */
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/* The real implementation of xFetch and xUnfetch */
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64 iOff, int iAmt, void **pp){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xFetch(id, iOff, iAmt, pp);
+}
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *id, i64 iOff, void *p){
+ return id->pMethods->xUnfetch(id, iOff, p);
+}
+#else
+/* No-op stubs to use when memory-mapped I/O is disabled */
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64 iOff, int iAmt, void **pp){
+ *pp = 0;
+ return SQLITE_OK;
+}
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *id, i64 iOff, void *p){
+ return SQLITE_OK;
+}
+#endif
+
+/*
+** The next group of routines are convenience wrappers around the
+** VFS methods.
+*/
+SQLITE_PRIVATE int sqlite3OsOpen(
+ sqlite3_vfs *pVfs,
+ const char *zPath,
+ sqlite3_file *pFile,
+ int flags,
+ int *pFlagsOut
+){
+ int rc;
+ DO_OS_MALLOC_TEST(0);
+ /* 0x87f7f is a mask of SQLITE_OPEN_ flags that are valid to be passed
+ ** down into the VFS layer. Some SQLITE_OPEN_ flags (for example,
+ ** SQLITE_OPEN_FULLMUTEX or SQLITE_OPEN_SHAREDCACHE) are blocked before
+ ** reaching the VFS. */
+ rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x87f7f, pFlagsOut);
+ assert( rc==SQLITE_OK || pFile->pMethods==0 );
+ return rc;
+}
+SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
+ DO_OS_MALLOC_TEST(0);
+ assert( dirSync==0 || dirSync==1 );
+ return pVfs->xDelete(pVfs, zPath, dirSync);
+}
+SQLITE_PRIVATE int sqlite3OsAccess(
+ sqlite3_vfs *pVfs,
+ const char *zPath,
+ int flags,
+ int *pResOut
+){
+ DO_OS_MALLOC_TEST(0);
+ return pVfs->xAccess(pVfs, zPath, flags, pResOut);
+}
+SQLITE_PRIVATE int sqlite3OsFullPathname(
+ sqlite3_vfs *pVfs,
+ const char *zPath,
+ int nPathOut,
+ char *zPathOut
+){
+ DO_OS_MALLOC_TEST(0);
+ zPathOut[0] = 0;
+ return pVfs->xFullPathname(pVfs, zPath, nPathOut, zPathOut);
+}
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
+ return pVfs->xDlOpen(pVfs, zPath);
+}
+SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
+ pVfs->xDlError(pVfs, nByte, zBufOut);
+}
+SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *pVfs, void *pHdle, const char *zSym))(void){
+ return pVfs->xDlSym(pVfs, pHdle, zSym);
+}
+SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *pVfs, void *pHandle){
+ pVfs->xDlClose(pVfs, pHandle);
+}
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
+SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
+ return pVfs->xRandomness(pVfs, nByte, zBufOut);
+}
+SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *pVfs, int nMicro){
+ return pVfs->xSleep(pVfs, nMicro);
+}
+SQLITE_PRIVATE int sqlite3OsGetLastError(sqlite3_vfs *pVfs){
+ return pVfs->xGetLastError ? pVfs->xGetLastError(pVfs, 0, 0) : 0;
+}
+SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *pTimeOut){
+ int rc;
+ /* IMPLEMENTATION-OF: R-49045-42493 SQLite will use the xCurrentTimeInt64()
+ ** method to get the current date and time if that method is available
+ ** (if iVersion is 2 or greater and the function pointer is not NULL) and
+ ** will fall back to xCurrentTime() if xCurrentTimeInt64() is
+ ** unavailable.
+ */
+ if( pVfs->iVersion>=2 && pVfs->xCurrentTimeInt64 ){
+ rc = pVfs->xCurrentTimeInt64(pVfs, pTimeOut);
+ }else{
+ double r;
+ rc = pVfs->xCurrentTime(pVfs, &r);
+ *pTimeOut = (sqlite3_int64)(r*86400000.0);
+ }
+ return rc;
+}
+
+SQLITE_PRIVATE int sqlite3OsOpenMalloc(
+ sqlite3_vfs *pVfs,
+ const char *zFile,
+ sqlite3_file **ppFile,
+ int flags,
+ int *pOutFlags
+){
+ int rc;
+ sqlite3_file *pFile;
+ pFile = (sqlite3_file *)sqlite3MallocZero(pVfs->szOsFile);
+ if( pFile ){
+ rc = sqlite3OsOpen(pVfs, zFile, pFile, flags, pOutFlags);
+ if( rc!=SQLITE_OK ){
+ sqlite3_free(pFile);
+ }else{
+ *ppFile = pFile;
+ }
+ }else{
+ rc = SQLITE_NOMEM_BKPT;
+ }
+ return rc;
+}
+SQLITE_PRIVATE void sqlite3OsCloseFree(sqlite3_file *pFile){
+ assert( pFile );
+ sqlite3OsClose(pFile);
+ sqlite3_free(pFile);
+}
+
+/*
+** This function is a wrapper around the OS specific implementation of
+** sqlite3_os_init(). The purpose of the wrapper is to provide the
+** ability to simulate a malloc failure, so that the handling of an
+** error in sqlite3_os_init() by the upper layers can be tested.
+*/
+SQLITE_PRIVATE int sqlite3OsInit(void){
+ void *p = sqlite3_malloc(10);
+ if( p==0 ) return SQLITE_NOMEM_BKPT;
+ sqlite3_free(p);
+ return sqlite3_os_init();
+}
+
+/*
+** The list of all registered VFS implementations.
+*/
+static sqlite3_vfs * SQLITE_WSD vfsList = 0;
+#define vfsList GLOBAL(sqlite3_vfs *, vfsList)
+
+/*
+** Locate a VFS by name. If no name is given, simply return the
+** first VFS on the list.
+*/
+SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
+ sqlite3_vfs *pVfs = 0;
+#if SQLITE_THREADSAFE
+ sqlite3_mutex *mutex;
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return 0;
+#endif
+#if SQLITE_THREADSAFE
+ mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+ sqlite3_mutex_enter(mutex);
+ for(pVfs = vfsList; pVfs; pVfs=pVfs->pNext){
+ if( zVfs==0 ) break;
+ if( strcmp(zVfs, pVfs->zName)==0 ) break;
+ }
+ sqlite3_mutex_leave(mutex);
+ return pVfs;
+}
+
+/*
+** Unlink a VFS from the linked list
+*/
+static void vfsUnlink(sqlite3_vfs *pVfs){
+ assert( sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER)) );
+ if( pVfs==0 ){
+ /* No-op */
+ }else if( vfsList==pVfs ){
+ vfsList = pVfs->pNext;
+ }else if( vfsList ){
+ sqlite3_vfs *p = vfsList;
+ while( p->pNext && p->pNext!=pVfs ){
+ p = p->pNext;
+ }
+ if( p->pNext==pVfs ){
+ p->pNext = pVfs->pNext;
+ }
+ }
+}
+
+/*
+** Register a VFS with the system. It is harmless to register the same
+** VFS multiple times. The new VFS becomes the default if makeDflt is
+** true.
+*/
+SQLITE_API int sqlite3_vfs_register(sqlite3_vfs *pVfs, int makeDflt){
+ MUTEX_LOGIC(sqlite3_mutex *mutex;)
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return rc;
+#endif
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( pVfs==0 ) return SQLITE_MISUSE_BKPT;
+#endif
+
+ MUTEX_LOGIC( mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER); )
+ sqlite3_mutex_enter(mutex);
+ vfsUnlink(pVfs);
+ if( makeDflt || vfsList==0 ){
+ pVfs->pNext = vfsList;
+ vfsList = pVfs;
+ }else{
+ pVfs->pNext = vfsList->pNext;
+ vfsList->pNext = pVfs;
+ }
+ assert(vfsList);
+ sqlite3_mutex_leave(mutex);
+ return SQLITE_OK;
+}
+
+/*
+** Unregister a VFS so that it is no longer accessible.
+*/
+SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs *pVfs){
+ MUTEX_LOGIC(sqlite3_mutex *mutex;)
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return rc;
+#endif
+ MUTEX_LOGIC( mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER); )
+ sqlite3_mutex_enter(mutex);
+ vfsUnlink(pVfs);
+ sqlite3_mutex_leave(mutex);
+ return SQLITE_OK;
+}
+
+/************** End of os.c **************************************************/
+/************** Begin file fault.c *******************************************/
+/*
+** 2008 Jan 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains code to support the concept of "benign"
+** malloc failures (when the xMalloc() or xRealloc() method of the
+** sqlite3_mem_methods structure fails to allocate a block of memory
+** and returns 0).
+**
+** Most malloc failures are non-benign. After they occur, SQLite
+** abandons the current operation and returns an error code (usually
+** SQLITE_NOMEM) to the user. However, sometimes a fault is not necessarily
+** fatal. For example, if a malloc fails while resizing a hash table, this
+** is completely recoverable simply by not carrying out the resize. The
+** hash table will continue to function normally. So a malloc failure
+** during a hash table resize is a benign fault.
+*/
+
+/* #include "sqliteInt.h" */
+
+#ifndef SQLITE_UNTESTABLE
+
+/*
+** Global variables.
+*/
+typedef struct BenignMallocHooks BenignMallocHooks;
+static SQLITE_WSD struct BenignMallocHooks {
+ void (*xBenignBegin)(void);
+ void (*xBenignEnd)(void);
+} sqlite3Hooks = { 0, 0 };
+
+/* The "wsdHooks" macro will resolve to the appropriate BenignMallocHooks
+** structure. If writable static data is unsupported on the target,
+** we have to locate the state vector at run-time. In the more common
+** case where writable static data is supported, wsdHooks can refer directly
+** to the "sqlite3Hooks" state vector declared above.
+*/
+#ifdef SQLITE_OMIT_WSD
+# define wsdHooksInit \
+ BenignMallocHooks *x = &GLOBAL(BenignMallocHooks,sqlite3Hooks)
+# define wsdHooks x[0]
+#else
+# define wsdHooksInit
+# define wsdHooks sqlite3Hooks
+#endif
+
+
+/*
+** Register hooks to call when sqlite3BeginBenignMalloc() and
+** sqlite3EndBenignMalloc() are called, respectively.
+*/
+SQLITE_PRIVATE void sqlite3BenignMallocHooks(
+ void (*xBenignBegin)(void),
+ void (*xBenignEnd)(void)
+){
+ wsdHooksInit;
+ wsdHooks.xBenignBegin = xBenignBegin;
+ wsdHooks.xBenignEnd = xBenignEnd;
+}
+
+/*
+** This (sqlite3EndBenignMalloc()) is called by SQLite code to indicate that
+** subsequent malloc failures are benign. A call to sqlite3EndBenignMalloc()
+** indicates that subsequent malloc failures are non-benign.
+*/
+SQLITE_PRIVATE void sqlite3BeginBenignMalloc(void){
+ wsdHooksInit;
+ if( wsdHooks.xBenignBegin ){
+ wsdHooks.xBenignBegin();
+ }
+}
+SQLITE_PRIVATE void sqlite3EndBenignMalloc(void){
+ wsdHooksInit;
+ if( wsdHooks.xBenignEnd ){
+ wsdHooks.xBenignEnd();
+ }
+}
+
+#endif /* #ifndef SQLITE_UNTESTABLE */
+
+/************** End of fault.c ***********************************************/
+/************** Begin file mem0.c ********************************************/
+/*
+** 2008 October 28
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains a no-op memory allocation drivers for use when
+** SQLITE_ZERO_MALLOC is defined. The allocation drivers implemented
+** here always fail. SQLite will not operate with these drivers. These
+** are merely placeholders. Real drivers must be substituted using
+** sqlite3_config() before SQLite will operate.
+*/
+/* #include "sqliteInt.h" */
+
+/*
+** This version of the memory allocator is the default. It is
+** used when no other memory allocator is specified using compile-time
+** macros.
+*/
+#ifdef SQLITE_ZERO_MALLOC
+
+/*
+** No-op versions of all memory allocation routines
+*/
+static void *sqlite3MemMalloc(int nByte){ return 0; }
+static void sqlite3MemFree(void *pPrior){ return; }
+static void *sqlite3MemRealloc(void *pPrior, int nByte){ return 0; }
+static int sqlite3MemSize(void *pPrior){ return 0; }
+static int sqlite3MemRoundup(int n){ return n; }
+static int sqlite3MemInit(void *NotUsed){ return SQLITE_OK; }
+static void sqlite3MemShutdown(void *NotUsed){ return; }
+
+/*
+** This routine is the only routine in this file with external linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
+*/
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+ static const sqlite3_mem_methods defaultMethods = {
+ sqlite3MemMalloc,
+ sqlite3MemFree,
+ sqlite3MemRealloc,
+ sqlite3MemSize,
+ sqlite3MemRoundup,
+ sqlite3MemInit,
+ sqlite3MemShutdown,
+ 0
+ };
+ sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
+}
+
+#endif /* SQLITE_ZERO_MALLOC */
+
+/************** End of mem0.c ************************************************/
+/************** Begin file mem1.c ********************************************/
+/*
+** 2007 August 14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains low-level memory allocation drivers for when
+** SQLite will use the standard C-library malloc/realloc/free interface
+** to obtain the memory it needs.
+**
+** This file contains implementations of the low-level memory allocation
+** routines specified in the sqlite3_mem_methods object. The content of
+** this file is only used if SQLITE_SYSTEM_MALLOC is defined. The
+** SQLITE_SYSTEM_MALLOC macro is defined automatically if neither the
+** SQLITE_MEMDEBUG nor the SQLITE_WIN32_MALLOC macros are defined. The
+** default configuration is to use memory allocation routines in this
+** file.
+**
+** C-preprocessor macro summary:
+**
+** HAVE_MALLOC_USABLE_SIZE The configure script sets this symbol if
+** the malloc_usable_size() interface exists
+** on the target platform. Or, this symbol
+** can be set manually, if desired.
+** If an equivalent interface exists by
+** a different name, using a separate -D
+** option to rename it.
+**
+** SQLITE_WITHOUT_ZONEMALLOC Some older macs lack support for the zone
+** memory allocator. Set this symbol to enable
+** building on older macs.
+**
+** SQLITE_WITHOUT_MSIZE Set this symbol to disable the use of
+** _msize() on windows systems. This might
+** be necessary when compiling for Delphi,
+** for example.
+*/
+/* #include "sqliteInt.h" */
+
+/*
+** This version of the memory allocator is the default. It is
+** used when no other memory allocator is specified using compile-time
+** macros.
+*/
+#ifdef SQLITE_SYSTEM_MALLOC
+#if defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC)
+
+/*
+** Use the zone allocator available on apple products unless the
+** SQLITE_WITHOUT_ZONEMALLOC symbol is defined.
+*/
+#include
+#include
+#ifdef SQLITE_MIGHT_BE_SINGLE_CORE
+#include
+#endif /* SQLITE_MIGHT_BE_SINGLE_CORE */
+static malloc_zone_t* _sqliteZone_;
+#define SQLITE_MALLOC(x) malloc_zone_malloc(_sqliteZone_, (x))
+#define SQLITE_FREE(x) malloc_zone_free(_sqliteZone_, (x));
+#define SQLITE_REALLOC(x,y) malloc_zone_realloc(_sqliteZone_, (x), (y))
+#define SQLITE_MALLOCSIZE(x) \
+ (_sqliteZone_ ? _sqliteZone_->size(_sqliteZone_,x) : malloc_size(x))
+
+#else /* if not __APPLE__ */
+
+/*
+** Use standard C library malloc and free on non-Apple systems.
+** Also used by Apple systems if SQLITE_WITHOUT_ZONEMALLOC is defined.
+*/
+#define SQLITE_MALLOC(x) malloc(x)
+#define SQLITE_FREE(x) free(x)
+#define SQLITE_REALLOC(x,y) realloc((x),(y))
+
+/*
+** The malloc.h header file is needed for malloc_usable_size() function
+** on some systems (e.g. Linux).
+*/
+#if HAVE_MALLOC_H && HAVE_MALLOC_USABLE_SIZE
+# define SQLITE_USE_MALLOC_H 1
+# define SQLITE_USE_MALLOC_USABLE_SIZE 1
+/*
+** The MSVCRT has malloc_usable_size(), but it is called _msize(). The
+** use of _msize() is automatic, but can be disabled by compiling with
+** -DSQLITE_WITHOUT_MSIZE. Using the _msize() function also requires
+** the malloc.h header file.
+*/
+#elif defined(_MSC_VER) && !defined(SQLITE_WITHOUT_MSIZE)
+# define SQLITE_USE_MALLOC_H
+# define SQLITE_USE_MSIZE
+#endif
+
+/*
+** Include the malloc.h header file, if necessary. Also set define macro
+** SQLITE_MALLOCSIZE to the appropriate function name, which is _msize()
+** for MSVC and malloc_usable_size() for most other systems (e.g. Linux).
+** The memory size function can always be overridden manually by defining
+** the macro SQLITE_MALLOCSIZE to the desired function name.
+*/
+#if defined(SQLITE_USE_MALLOC_H)
+# include
+# if defined(SQLITE_USE_MALLOC_USABLE_SIZE)
+# if !defined(SQLITE_MALLOCSIZE)
+# define SQLITE_MALLOCSIZE(x) malloc_usable_size(x)
+# endif
+# elif defined(SQLITE_USE_MSIZE)
+# if !defined(SQLITE_MALLOCSIZE)
+# define SQLITE_MALLOCSIZE _msize
+# endif
+# endif
+#endif /* defined(SQLITE_USE_MALLOC_H) */
+
+#endif /* __APPLE__ or not __APPLE__ */
+
+/*
+** Like malloc(), but remember the size of the allocation
+** so that we can find it later using sqlite3MemSize().
+**
+** For this low-level routine, we are guaranteed that nByte>0 because
+** cases of nByte<=0 will be intercepted and dealt with by higher level
+** routines.
+*/
+static void *sqlite3MemMalloc(int nByte){
+#ifdef SQLITE_MALLOCSIZE
+ void *p;
+ testcase( ROUND8(nByte)==nByte );
+ p = SQLITE_MALLOC( nByte );
+ if( p==0 ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes of memory", nByte);
+ }
+ return p;
+#else
+ sqlite3_int64 *p;
+ assert( nByte>0 );
+ testcase( ROUND8(nByte)!=nByte );
+ p = SQLITE_MALLOC( nByte+8 );
+ if( p ){
+ p[0] = nByte;
+ p++;
+ }else{
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes of memory", nByte);
+ }
+ return (void *)p;
+#endif
+}
+
+/*
+** Like free() but works for allocations obtained from sqlite3MemMalloc()
+** or sqlite3MemRealloc().
+**
+** For this low-level routine, we already know that pPrior!=0 since
+** cases where pPrior==0 will have been intecepted and dealt with
+** by higher-level routines.
+*/
+static void sqlite3MemFree(void *pPrior){
+#ifdef SQLITE_MALLOCSIZE
+ SQLITE_FREE(pPrior);
+#else
+ sqlite3_int64 *p = (sqlite3_int64*)pPrior;
+ assert( pPrior!=0 );
+ p--;
+ SQLITE_FREE(p);
+#endif
+}
+
+/*
+** Report the allocated size of a prior return from xMalloc()
+** or xRealloc().
+*/
+static int sqlite3MemSize(void *pPrior){
+#ifdef SQLITE_MALLOCSIZE
+ assert( pPrior!=0 );
+ return (int)SQLITE_MALLOCSIZE(pPrior);
+#else
+ sqlite3_int64 *p;
+ assert( pPrior!=0 );
+ p = (sqlite3_int64*)pPrior;
+ p--;
+ return (int)p[0];
+#endif
+}
+
+/*
+** Like realloc(). Resize an allocation previously obtained from
+** sqlite3MemMalloc().
+**
+** For this low-level interface, we know that pPrior!=0. Cases where
+** pPrior==0 while have been intercepted by higher-level routine and
+** redirected to xMalloc. Similarly, we know that nByte>0 because
+** cases where nByte<=0 will have been intercepted by higher-level
+** routines and redirected to xFree.
+*/
+static void *sqlite3MemRealloc(void *pPrior, int nByte){
+#ifdef SQLITE_MALLOCSIZE
+ void *p = SQLITE_REALLOC(pPrior, nByte);
+ if( p==0 ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM,
+ "failed memory resize %u to %u bytes",
+ SQLITE_MALLOCSIZE(pPrior), nByte);
+ }
+ return p;
+#else
+ sqlite3_int64 *p = (sqlite3_int64*)pPrior;
+ assert( pPrior!=0 && nByte>0 );
+ assert( nByte==ROUND8(nByte) ); /* EV: R-46199-30249 */
+ p--;
+ p = SQLITE_REALLOC(p, nByte+8 );
+ if( p ){
+ p[0] = nByte;
+ p++;
+ }else{
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM,
+ "failed memory resize %u to %u bytes",
+ sqlite3MemSize(pPrior), nByte);
+ }
+ return (void*)p;
+#endif
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int sqlite3MemRoundup(int n){
+ return ROUND8(n);
+}
+
+/*
+** Initialize this module.
+*/
+static int sqlite3MemInit(void *NotUsed){
+#if defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC)
+ int cpuCount;
+ size_t len;
+ if( _sqliteZone_ ){
+ return SQLITE_OK;
+ }
+ len = sizeof(cpuCount);
+ /* One usually wants to use hw.acctivecpu for MT decisions, but not here */
+ sysctlbyname("hw.ncpu", &cpuCount, &len, NULL, 0);
+ if( cpuCount>1 ){
+ /* defer MT decisions to system malloc */
+ _sqliteZone_ = malloc_default_zone();
+ }else{
+ /* only 1 core, use our own zone to contention over global locks,
+ ** e.g. we have our own dedicated locks */
+ _sqliteZone_ = malloc_create_zone(4096, 0);
+ malloc_set_zone_name(_sqliteZone_, "Sqlite_Heap");
+ }
+#endif /* defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC) */
+ UNUSED_PARAMETER(NotUsed);
+ return SQLITE_OK;
+}
+
+/*
+** Deinitialize this module.
+*/
+static void sqlite3MemShutdown(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ return;
+}
+
+/*
+** This routine is the only routine in this file with external linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
+*/
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+ static const sqlite3_mem_methods defaultMethods = {
+ sqlite3MemMalloc,
+ sqlite3MemFree,
+ sqlite3MemRealloc,
+ sqlite3MemSize,
+ sqlite3MemRoundup,
+ sqlite3MemInit,
+ sqlite3MemShutdown,
+ 0
+ };
+ sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
+}
+
+#endif /* SQLITE_SYSTEM_MALLOC */
+
+/************** End of mem1.c ************************************************/
+/************** Begin file mem2.c ********************************************/
+/*
+** 2007 August 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains low-level memory allocation drivers for when
+** SQLite will use the standard C-library malloc/realloc/free interface
+** to obtain the memory it needs while adding lots of additional debugging
+** information to each allocation in order to help detect and fix memory
+** leaks and memory usage errors.
+**
+** This file contains implementations of the low-level memory allocation
+** routines specified in the sqlite3_mem_methods object.
+*/
+/* #include "sqliteInt.h" */
+
+/*
+** This version of the memory allocator is used only if the
+** SQLITE_MEMDEBUG macro is defined
+*/
+#ifdef SQLITE_MEMDEBUG
+
+/*
+** The backtrace functionality is only available with GLIBC
+*/
+#ifdef __GLIBC__
+ extern int backtrace(void**,int);
+ extern void backtrace_symbols_fd(void*const*,int,int);
+#else
+# define backtrace(A,B) 1
+# define backtrace_symbols_fd(A,B,C)
+#endif
+/* #include */
+
+/*
+** Each memory allocation looks like this:
+**
+** ------------------------------------------------------------------------
+** | Title | backtrace pointers | MemBlockHdr | allocation | EndGuard |
+** ------------------------------------------------------------------------
+**
+** The application code sees only a pointer to the allocation. We have
+** to back up from the allocation pointer to find the MemBlockHdr. The
+** MemBlockHdr tells us the size of the allocation and the number of
+** backtrace pointers. There is also a guard word at the end of the
+** MemBlockHdr.
+*/
+struct MemBlockHdr {
+ i64 iSize; /* Size of this allocation */
+ struct MemBlockHdr *pNext, *pPrev; /* Linked list of all unfreed memory */
+ char nBacktrace; /* Number of backtraces on this alloc */
+ char nBacktraceSlots; /* Available backtrace slots */
+ u8 nTitle; /* Bytes of title; includes '\0' */
+ u8 eType; /* Allocation type code */
+ int iForeGuard; /* Guard word for sanity */
+};
+
+/*
+** Guard words
+*/
+#define FOREGUARD 0x80F5E153
+#define REARGUARD 0xE4676B53
+
+/*
+** Number of malloc size increments to track.
+*/
+#define NCSIZE 1000
+
+/*
+** All of the static variables used by this module are collected
+** into a single structure named "mem". This is to keep the
+** static variables organized and to reduce namespace pollution
+** when this module is combined with other in the amalgamation.
+*/
+static struct {
+
+ /*
+ ** Mutex to control access to the memory allocation subsystem.
+ */
+ sqlite3_mutex *mutex;
+
+ /*
+ ** Head and tail of a linked list of all outstanding allocations
+ */
+ struct MemBlockHdr *pFirst;
+ struct MemBlockHdr *pLast;
+
+ /*
+ ** The number of levels of backtrace to save in new allocations.
+ */
+ int nBacktrace;
+ void (*xBacktrace)(int, int, void **);
+
+ /*
+ ** Title text to insert in front of each block
+ */
+ int nTitle; /* Bytes of zTitle to save. Includes '\0' and padding */
+ char zTitle[100]; /* The title text */
+
+ /*
+ ** sqlite3MallocDisallow() increments the following counter.
+ ** sqlite3MallocAllow() decrements it.
+ */
+ int disallow; /* Do not allow memory allocation */
+
+ /*
+ ** Gather statistics on the sizes of memory allocations.
+ ** nAlloc[i] is the number of allocation attempts of i*8
+ ** bytes. i==NCSIZE is the number of allocation attempts for
+ ** sizes more than NCSIZE*8 bytes.
+ */
+ int nAlloc[NCSIZE]; /* Total number of allocations */
+ int nCurrent[NCSIZE]; /* Current number of allocations */
+ int mxCurrent[NCSIZE]; /* Highwater mark for nCurrent */
+
+} mem;
+
+
+/*
+** Adjust memory usage statistics
+*/
+static void adjustStats(int iSize, int increment){
+ int i = ROUND8(iSize)/8;
+ if( i>NCSIZE-1 ){
+ i = NCSIZE - 1;
+ }
+ if( increment>0 ){
+ mem.nAlloc[i]++;
+ mem.nCurrent[i]++;
+ if( mem.nCurrent[i]>mem.mxCurrent[i] ){
+ mem.mxCurrent[i] = mem.nCurrent[i];
+ }
+ }else{
+ mem.nCurrent[i]--;
+ assert( mem.nCurrent[i]>=0 );
+ }
+}
+
+/*
+** Given an allocation, find the MemBlockHdr for that allocation.
+**
+** This routine checks the guards at either end of the allocation and
+** if they are incorrect it asserts.
+*/
+static struct MemBlockHdr *sqlite3MemsysGetHeader(void *pAllocation){
+ struct MemBlockHdr *p;
+ int *pInt;
+ u8 *pU8;
+ int nReserve;
+
+ p = (struct MemBlockHdr*)pAllocation;
+ p--;
+ assert( p->iForeGuard==(int)FOREGUARD );
+ nReserve = ROUND8(p->iSize);
+ pInt = (int*)pAllocation;
+ pU8 = (u8*)pAllocation;
+ assert( pInt[nReserve/sizeof(int)]==(int)REARGUARD );
+ /* This checks any of the "extra" bytes allocated due
+ ** to rounding up to an 8 byte boundary to ensure
+ ** they haven't been overwritten.
+ */
+ while( nReserve-- > p->iSize ) assert( pU8[nReserve]==0x65 );
+ return p;
+}
+
+/*
+** Return the number of bytes currently allocated at address p.
+*/
+static int sqlite3MemSize(void *p){
+ struct MemBlockHdr *pHdr;
+ if( !p ){
+ return 0;
+ }
+ pHdr = sqlite3MemsysGetHeader(p);
+ return (int)pHdr->iSize;
+}
+
+/*
+** Initialize the memory allocation subsystem.
+*/
+static int sqlite3MemInit(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ assert( (sizeof(struct MemBlockHdr)&7) == 0 );
+ if( !sqlite3GlobalConfig.bMemstat ){
+ /* If memory status is enabled, then the malloc.c wrapper will already
+ ** hold the STATIC_MEM mutex when the routines here are invoked. */
+ mem.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Deinitialize the memory allocation subsystem.
+*/
+static void sqlite3MemShutdown(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ mem.mutex = 0;
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int sqlite3MemRoundup(int n){
+ return ROUND8(n);
+}
+
+/*
+** Fill a buffer with pseudo-random bytes. This is used to preset
+** the content of a new memory allocation to unpredictable values and
+** to clear the content of a freed allocation to unpredictable values.
+*/
+static void randomFill(char *pBuf, int nByte){
+ unsigned int x, y, r;
+ x = SQLITE_PTR_TO_INT(pBuf);
+ y = nByte | 1;
+ while( nByte >= 4 ){
+ x = (x>>1) ^ (-(int)(x&1) & 0xd0000001);
+ y = y*1103515245 + 12345;
+ r = x ^ y;
+ *(int*)pBuf = r;
+ pBuf += 4;
+ nByte -= 4;
+ }
+ while( nByte-- > 0 ){
+ x = (x>>1) ^ (-(int)(x&1) & 0xd0000001);
+ y = y*1103515245 + 12345;
+ r = x ^ y;
+ *(pBuf++) = r & 0xff;
+ }
+}
+
+/*
+** Allocate nByte bytes of memory.
+*/
+static void *sqlite3MemMalloc(int nByte){
+ struct MemBlockHdr *pHdr;
+ void **pBt;
+ char *z;
+ int *pInt;
+ void *p = 0;
+ int totalSize;
+ int nReserve;
+ sqlite3_mutex_enter(mem.mutex);
+ assert( mem.disallow==0 );
+ nReserve = ROUND8(nByte);
+ totalSize = nReserve + sizeof(*pHdr) + sizeof(int) +
+ mem.nBacktrace*sizeof(void*) + mem.nTitle;
+ p = malloc(totalSize);
+ if( p ){
+ z = p;
+ pBt = (void**)&z[mem.nTitle];
+ pHdr = (struct MemBlockHdr*)&pBt[mem.nBacktrace];
+ pHdr->pNext = 0;
+ pHdr->pPrev = mem.pLast;
+ if( mem.pLast ){
+ mem.pLast->pNext = pHdr;
+ }else{
+ mem.pFirst = pHdr;
+ }
+ mem.pLast = pHdr;
+ pHdr->iForeGuard = FOREGUARD;
+ pHdr->eType = MEMTYPE_HEAP;
+ pHdr->nBacktraceSlots = mem.nBacktrace;
+ pHdr->nTitle = mem.nTitle;
+ if( mem.nBacktrace ){
+ void *aAddr[40];
+ pHdr->nBacktrace = backtrace(aAddr, mem.nBacktrace+1)-1;
+ memcpy(pBt, &aAddr[1], pHdr->nBacktrace*sizeof(void*));
+ assert(pBt[0]);
+ if( mem.xBacktrace ){
+ mem.xBacktrace(nByte, pHdr->nBacktrace-1, &aAddr[1]);
+ }
+ }else{
+ pHdr->nBacktrace = 0;
+ }
+ if( mem.nTitle ){
+ memcpy(z, mem.zTitle, mem.nTitle);
+ }
+ pHdr->iSize = nByte;
+ adjustStats(nByte, +1);
+ pInt = (int*)&pHdr[1];
+ pInt[nReserve/sizeof(int)] = REARGUARD;
+ randomFill((char*)pInt, nByte);
+ memset(((char*)pInt)+nByte, 0x65, nReserve-nByte);
+ p = (void*)pInt;
+ }
+ sqlite3_mutex_leave(mem.mutex);
+ return p;
+}
+
+/*
+** Free memory.
+*/
+static void sqlite3MemFree(void *pPrior){
+ struct MemBlockHdr *pHdr;
+ void **pBt;
+ char *z;
+ assert( sqlite3GlobalConfig.bMemstat || sqlite3GlobalConfig.bCoreMutex==0
+ || mem.mutex!=0 );
+ pHdr = sqlite3MemsysGetHeader(pPrior);
+ pBt = (void**)pHdr;
+ pBt -= pHdr->nBacktraceSlots;
+ sqlite3_mutex_enter(mem.mutex);
+ if( pHdr->pPrev ){
+ assert( pHdr->pPrev->pNext==pHdr );
+ pHdr->pPrev->pNext = pHdr->pNext;
+ }else{
+ assert( mem.pFirst==pHdr );
+ mem.pFirst = pHdr->pNext;
+ }
+ if( pHdr->pNext ){
+ assert( pHdr->pNext->pPrev==pHdr );
+ pHdr->pNext->pPrev = pHdr->pPrev;
+ }else{
+ assert( mem.pLast==pHdr );
+ mem.pLast = pHdr->pPrev;
+ }
+ z = (char*)pBt;
+ z -= pHdr->nTitle;
+ adjustStats((int)pHdr->iSize, -1);
+ randomFill(z, sizeof(void*)*pHdr->nBacktraceSlots + sizeof(*pHdr) +
+ (int)pHdr->iSize + sizeof(int) + pHdr->nTitle);
+ free(z);
+ sqlite3_mutex_leave(mem.mutex);
+}
+
+/*
+** Change the size of an existing memory allocation.
+**
+** For this debugging implementation, we *always* make a copy of the
+** allocation into a new place in memory. In this way, if the
+** higher level code is using pointer to the old allocation, it is
+** much more likely to break and we are much more liking to find
+** the error.
+*/
+static void *sqlite3MemRealloc(void *pPrior, int nByte){
+ struct MemBlockHdr *pOldHdr;
+ void *pNew;
+ assert( mem.disallow==0 );
+ assert( (nByte & 7)==0 ); /* EV: R-46199-30249 */
+ pOldHdr = sqlite3MemsysGetHeader(pPrior);
+ pNew = sqlite3MemMalloc(nByte);
+ if( pNew ){
+ memcpy(pNew, pPrior, (int)(nByteiSize ? nByte : pOldHdr->iSize));
+ if( nByte>pOldHdr->iSize ){
+ randomFill(&((char*)pNew)[pOldHdr->iSize], nByte - (int)pOldHdr->iSize);
+ }
+ sqlite3MemFree(pPrior);
+ }
+ return pNew;
+}
+
+/*
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
+*/
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+ static const sqlite3_mem_methods defaultMethods = {
+ sqlite3MemMalloc,
+ sqlite3MemFree,
+ sqlite3MemRealloc,
+ sqlite3MemSize,
+ sqlite3MemRoundup,
+ sqlite3MemInit,
+ sqlite3MemShutdown,
+ 0
+ };
+ sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
+}
+
+/*
+** Set the "type" of an allocation.
+*/
+SQLITE_PRIVATE void sqlite3MemdebugSetType(void *p, u8 eType){
+ if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
+ struct MemBlockHdr *pHdr;
+ pHdr = sqlite3MemsysGetHeader(p);
+ assert( pHdr->iForeGuard==FOREGUARD );
+ pHdr->eType = eType;
+ }
+}
+
+/*
+** Return TRUE if the mask of type in eType matches the type of the
+** allocation p. Also return true if p==NULL.
+**
+** This routine is designed for use within an assert() statement, to
+** verify the type of an allocation. For example:
+**
+** assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+*/
+SQLITE_PRIVATE int sqlite3MemdebugHasType(void *p, u8 eType){
+ int rc = 1;
+ if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
+ struct MemBlockHdr *pHdr;
+ pHdr = sqlite3MemsysGetHeader(p);
+ assert( pHdr->iForeGuard==FOREGUARD ); /* Allocation is valid */
+ if( (pHdr->eType&eType)==0 ){
+ rc = 0;
+ }
+ }
+ return rc;
+}
+
+/*
+** Return TRUE if the mask of type in eType matches no bits of the type of the
+** allocation p. Also return true if p==NULL.
+**
+** This routine is designed for use within an assert() statement, to
+** verify the type of an allocation. For example:
+**
+** assert( sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
+*/
+SQLITE_PRIVATE int sqlite3MemdebugNoType(void *p, u8 eType){
+ int rc = 1;
+ if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
+ struct MemBlockHdr *pHdr;
+ pHdr = sqlite3MemsysGetHeader(p);
+ assert( pHdr->iForeGuard==FOREGUARD ); /* Allocation is valid */
+ if( (pHdr->eType&eType)!=0 ){
+ rc = 0;
+ }
+ }
+ return rc;
+}
+
+/*
+** Set the number of backtrace levels kept for each allocation.
+** A value of zero turns off backtracing. The number is always rounded
+** up to a multiple of 2.
+*/
+SQLITE_PRIVATE void sqlite3MemdebugBacktrace(int depth){
+ if( depth<0 ){ depth = 0; }
+ if( depth>20 ){ depth = 20; }
+ depth = (depth+1)&0xfe;
+ mem.nBacktrace = depth;
+}
+
+SQLITE_PRIVATE void sqlite3MemdebugBacktraceCallback(void (*xBacktrace)(int, int, void **)){
+ mem.xBacktrace = xBacktrace;
+}
+
+/*
+** Set the title string for subsequent allocations.
+*/
+SQLITE_PRIVATE void sqlite3MemdebugSettitle(const char *zTitle){
+ unsigned int n = sqlite3Strlen30(zTitle) + 1;
+ sqlite3_mutex_enter(mem.mutex);
+ if( n>=sizeof(mem.zTitle) ) n = sizeof(mem.zTitle)-1;
+ memcpy(mem.zTitle, zTitle, n);
+ mem.zTitle[n] = 0;
+ mem.nTitle = ROUND8(n);
+ sqlite3_mutex_leave(mem.mutex);
+}
+
+SQLITE_PRIVATE void sqlite3MemdebugSync(){
+ struct MemBlockHdr *pHdr;
+ for(pHdr=mem.pFirst; pHdr; pHdr=pHdr->pNext){
+ void **pBt = (void**)pHdr;
+ pBt -= pHdr->nBacktraceSlots;
+ mem.xBacktrace((int)pHdr->iSize, pHdr->nBacktrace-1, &pBt[1]);
+ }
+}
+
+/*
+** Open the file indicated and write a log of all unfreed memory
+** allocations into that log.
+*/
+SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
+ FILE *out;
+ struct MemBlockHdr *pHdr;
+ void **pBt;
+ int i;
+ out = fopen(zFilename, "w");
+ if( out==0 ){
+ fprintf(stderr, "** Unable to output memory debug output log: %s **\n",
+ zFilename);
+ return;
+ }
+ for(pHdr=mem.pFirst; pHdr; pHdr=pHdr->pNext){
+ char *z = (char*)pHdr;
+ z -= pHdr->nBacktraceSlots*sizeof(void*) + pHdr->nTitle;
+ fprintf(out, "**** %lld bytes at %p from %s ****\n",
+ pHdr->iSize, &pHdr[1], pHdr->nTitle ? z : "???");
+ if( pHdr->nBacktrace ){
+ fflush(out);
+ pBt = (void**)pHdr;
+ pBt -= pHdr->nBacktraceSlots;
+ backtrace_symbols_fd(pBt, pHdr->nBacktrace, fileno(out));
+ fprintf(out, "\n");
+ }
+ }
+ fprintf(out, "COUNTS:\n");
+ for(i=0; i=1 );
+ size = mem3.aPool[i-1].u.hdr.size4x/4;
+ assert( size==mem3.aPool[i+size-1].u.hdr.prevSize );
+ assert( size>=2 );
+ if( size <= MX_SMALL ){
+ memsys3UnlinkFromList(i, &mem3.aiSmall[size-2]);
+ }else{
+ hash = size % N_HASH;
+ memsys3UnlinkFromList(i, &mem3.aiHash[hash]);
+ }
+}
+
+/*
+** Link the chunk at mem3.aPool[i] so that is on the list rooted
+** at *pRoot.
+*/
+static void memsys3LinkIntoList(u32 i, u32 *pRoot){
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ mem3.aPool[i].u.list.next = *pRoot;
+ mem3.aPool[i].u.list.prev = 0;
+ if( *pRoot ){
+ mem3.aPool[*pRoot].u.list.prev = i;
+ }
+ *pRoot = i;
+}
+
+/*
+** Link the chunk at index i into either the appropriate
+** small chunk list, or into the large chunk hash table.
+*/
+static void memsys3Link(u32 i){
+ u32 size, hash;
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( i>=1 );
+ assert( (mem3.aPool[i-1].u.hdr.size4x & 1)==0 );
+ size = mem3.aPool[i-1].u.hdr.size4x/4;
+ assert( size==mem3.aPool[i+size-1].u.hdr.prevSize );
+ assert( size>=2 );
+ if( size <= MX_SMALL ){
+ memsys3LinkIntoList(i, &mem3.aiSmall[size-2]);
+ }else{
+ hash = size % N_HASH;
+ memsys3LinkIntoList(i, &mem3.aiHash[hash]);
+ }
+}
+
+/*
+** If the STATIC_MEM mutex is not already held, obtain it now. The mutex
+** will already be held (obtained by code in malloc.c) if
+** sqlite3GlobalConfig.bMemStat is true.
+*/
+static void memsys3Enter(void){
+ if( sqlite3GlobalConfig.bMemstat==0 && mem3.mutex==0 ){
+ mem3.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+ }
+ sqlite3_mutex_enter(mem3.mutex);
+}
+static void memsys3Leave(void){
+ sqlite3_mutex_leave(mem3.mutex);
+}
+
+/*
+** Called when we are unable to satisfy an allocation of nBytes.
+*/
+static void memsys3OutOfMemory(int nByte){
+ if( !mem3.alarmBusy ){
+ mem3.alarmBusy = 1;
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ sqlite3_mutex_leave(mem3.mutex);
+ sqlite3_release_memory(nByte);
+ sqlite3_mutex_enter(mem3.mutex);
+ mem3.alarmBusy = 0;
+ }
+}
+
+
+/*
+** Chunk i is a free chunk that has been unlinked. Adjust its
+** size parameters for check-out and return a pointer to the
+** user portion of the chunk.
+*/
+static void *memsys3Checkout(u32 i, u32 nBlock){
+ u32 x;
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( i>=1 );
+ assert( mem3.aPool[i-1].u.hdr.size4x/4==nBlock );
+ assert( mem3.aPool[i+nBlock-1].u.hdr.prevSize==nBlock );
+ x = mem3.aPool[i-1].u.hdr.size4x;
+ mem3.aPool[i-1].u.hdr.size4x = nBlock*4 | 1 | (x&2);
+ mem3.aPool[i+nBlock-1].u.hdr.prevSize = nBlock;
+ mem3.aPool[i+nBlock-1].u.hdr.size4x |= 2;
+ return &mem3.aPool[i];
+}
+
+/*
+** Carve a piece off of the end of the mem3.iMaster free chunk.
+** Return a pointer to the new allocation. Or, if the master chunk
+** is not large enough, return 0.
+*/
+static void *memsys3FromMaster(u32 nBlock){
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( mem3.szMaster>=nBlock );
+ if( nBlock>=mem3.szMaster-1 ){
+ /* Use the entire master */
+ void *p = memsys3Checkout(mem3.iMaster, mem3.szMaster);
+ mem3.iMaster = 0;
+ mem3.szMaster = 0;
+ mem3.mnMaster = 0;
+ return p;
+ }else{
+ /* Split the master block. Return the tail. */
+ u32 newi, x;
+ newi = mem3.iMaster + mem3.szMaster - nBlock;
+ assert( newi > mem3.iMaster+1 );
+ mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = nBlock;
+ mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x |= 2;
+ mem3.aPool[newi-1].u.hdr.size4x = nBlock*4 + 1;
+ mem3.szMaster -= nBlock;
+ mem3.aPool[newi-1].u.hdr.prevSize = mem3.szMaster;
+ x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+ mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+ if( mem3.szMaster < mem3.mnMaster ){
+ mem3.mnMaster = mem3.szMaster;
+ }
+ return (void*)&mem3.aPool[newi];
+ }
+}
+
+/*
+** *pRoot is the head of a list of free chunks of the same size
+** or same size hash. In other words, *pRoot is an entry in either
+** mem3.aiSmall[] or mem3.aiHash[].
+**
+** This routine examines all entries on the given list and tries
+** to coalesce each entries with adjacent free chunks.
+**
+** If it sees a chunk that is larger than mem3.iMaster, it replaces
+** the current mem3.iMaster with the new larger chunk. In order for
+** this mem3.iMaster replacement to work, the master chunk must be
+** linked into the hash tables. That is not the normal state of
+** affairs, of course. The calling routine must link the master
+** chunk before invoking this routine, then must unlink the (possibly
+** changed) master chunk once this routine has finished.
+*/
+static void memsys3Merge(u32 *pRoot){
+ u32 iNext, prev, size, i, x;
+
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ for(i=*pRoot; i>0; i=iNext){
+ iNext = mem3.aPool[i].u.list.next;
+ size = mem3.aPool[i-1].u.hdr.size4x;
+ assert( (size&1)==0 );
+ if( (size&2)==0 ){
+ memsys3UnlinkFromList(i, pRoot);
+ assert( i > mem3.aPool[i-1].u.hdr.prevSize );
+ prev = i - mem3.aPool[i-1].u.hdr.prevSize;
+ if( prev==iNext ){
+ iNext = mem3.aPool[prev].u.list.next;
+ }
+ memsys3Unlink(prev);
+ size = i + size/4 - prev;
+ x = mem3.aPool[prev-1].u.hdr.size4x & 2;
+ mem3.aPool[prev-1].u.hdr.size4x = size*4 | x;
+ mem3.aPool[prev+size-1].u.hdr.prevSize = size;
+ memsys3Link(prev);
+ i = prev;
+ }else{
+ size /= 4;
+ }
+ if( size>mem3.szMaster ){
+ mem3.iMaster = i;
+ mem3.szMaster = size;
+ }
+ }
+}
+
+/*
+** Return a block of memory of at least nBytes in size.
+** Return NULL if unable.
+**
+** This function assumes that the necessary mutexes, if any, are
+** already held by the caller. Hence "Unsafe".
+*/
+static void *memsys3MallocUnsafe(int nByte){
+ u32 i;
+ u32 nBlock;
+ u32 toFree;
+
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( sizeof(Mem3Block)==8 );
+ if( nByte<=12 ){
+ nBlock = 2;
+ }else{
+ nBlock = (nByte + 11)/8;
+ }
+ assert( nBlock>=2 );
+
+ /* STEP 1:
+ ** Look for an entry of the correct size in either the small
+ ** chunk table or in the large chunk hash table. This is
+ ** successful most of the time (about 9 times out of 10).
+ */
+ if( nBlock <= MX_SMALL ){
+ i = mem3.aiSmall[nBlock-2];
+ if( i>0 ){
+ memsys3UnlinkFromList(i, &mem3.aiSmall[nBlock-2]);
+ return memsys3Checkout(i, nBlock);
+ }
+ }else{
+ int hash = nBlock % N_HASH;
+ for(i=mem3.aiHash[hash]; i>0; i=mem3.aPool[i].u.list.next){
+ if( mem3.aPool[i-1].u.hdr.size4x/4==nBlock ){
+ memsys3UnlinkFromList(i, &mem3.aiHash[hash]);
+ return memsys3Checkout(i, nBlock);
+ }
+ }
+ }
+
+ /* STEP 2:
+ ** Try to satisfy the allocation by carving a piece off of the end
+ ** of the master chunk. This step usually works if step 1 fails.
+ */
+ if( mem3.szMaster>=nBlock ){
+ return memsys3FromMaster(nBlock);
+ }
+
+
+ /* STEP 3:
+ ** Loop through the entire memory pool. Coalesce adjacent free
+ ** chunks. Recompute the master chunk as the largest free chunk.
+ ** Then try again to satisfy the allocation by carving a piece off
+ ** of the end of the master chunk. This step happens very
+ ** rarely (we hope!)
+ */
+ for(toFree=nBlock*16; toFree<(mem3.nPool*16); toFree *= 2){
+ memsys3OutOfMemory(toFree);
+ if( mem3.iMaster ){
+ memsys3Link(mem3.iMaster);
+ mem3.iMaster = 0;
+ mem3.szMaster = 0;
+ }
+ for(i=0; i=nBlock ){
+ return memsys3FromMaster(nBlock);
+ }
+ }
+ }
+
+ /* If none of the above worked, then we fail. */
+ return 0;
+}
+
+/*
+** Free an outstanding memory allocation.
+**
+** This function assumes that the necessary mutexes, if any, are
+** already held by the caller. Hence "Unsafe".
+*/
+static void memsys3FreeUnsafe(void *pOld){
+ Mem3Block *p = (Mem3Block*)pOld;
+ int i;
+ u32 size, x;
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( p>mem3.aPool && p<&mem3.aPool[mem3.nPool] );
+ i = p - mem3.aPool;
+ assert( (mem3.aPool[i-1].u.hdr.size4x&1)==1 );
+ size = mem3.aPool[i-1].u.hdr.size4x/4;
+ assert( i+size<=mem3.nPool+1 );
+ mem3.aPool[i-1].u.hdr.size4x &= ~1;
+ mem3.aPool[i+size-1].u.hdr.prevSize = size;
+ mem3.aPool[i+size-1].u.hdr.size4x &= ~2;
+ memsys3Link(i);
+
+ /* Try to expand the master using the newly freed chunk */
+ if( mem3.iMaster ){
+ while( (mem3.aPool[mem3.iMaster-1].u.hdr.size4x&2)==0 ){
+ size = mem3.aPool[mem3.iMaster-1].u.hdr.prevSize;
+ mem3.iMaster -= size;
+ mem3.szMaster += size;
+ memsys3Unlink(mem3.iMaster);
+ x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+ mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+ mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster;
+ }
+ x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+ while( (mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x&1)==0 ){
+ memsys3Unlink(mem3.iMaster+mem3.szMaster);
+ mem3.szMaster += mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x/4;
+ mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+ mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster;
+ }
+ }
+}
+
+/*
+** Return the size of an outstanding allocation, in bytes. The
+** size returned omits the 8-byte header overhead. This only
+** works for chunks that are currently checked out.
+*/
+static int memsys3Size(void *p){
+ Mem3Block *pBlock;
+ assert( p!=0 );
+ pBlock = (Mem3Block*)p;
+ assert( (pBlock[-1].u.hdr.size4x&1)!=0 );
+ return (pBlock[-1].u.hdr.size4x&~3)*2 - 4;
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int memsys3Roundup(int n){
+ if( n<=12 ){
+ return 12;
+ }else{
+ return ((n+11)&~7) - 4;
+ }
+}
+
+/*
+** Allocate nBytes of memory.
+*/
+static void *memsys3Malloc(int nBytes){
+ sqlite3_int64 *p;
+ assert( nBytes>0 ); /* malloc.c filters out 0 byte requests */
+ memsys3Enter();
+ p = memsys3MallocUnsafe(nBytes);
+ memsys3Leave();
+ return (void*)p;
+}
+
+/*
+** Free memory.
+*/
+static void memsys3Free(void *pPrior){
+ assert( pPrior );
+ memsys3Enter();
+ memsys3FreeUnsafe(pPrior);
+ memsys3Leave();
+}
+
+/*
+** Change the size of an existing memory allocation
+*/
+static void *memsys3Realloc(void *pPrior, int nBytes){
+ int nOld;
+ void *p;
+ if( pPrior==0 ){
+ return sqlite3_malloc(nBytes);
+ }
+ if( nBytes<=0 ){
+ sqlite3_free(pPrior);
+ return 0;
+ }
+ nOld = memsys3Size(pPrior);
+ if( nBytes<=nOld && nBytes>=nOld-128 ){
+ return pPrior;
+ }
+ memsys3Enter();
+ p = memsys3MallocUnsafe(nBytes);
+ if( p ){
+ if( nOld>1)!=(size&1) ){
+ fprintf(out, "%p tail checkout bit is incorrect\n", &mem3.aPool[i]);
+ assert( 0 );
+ break;
+ }
+ if( size&1 ){
+ fprintf(out, "%p %6d bytes checked out\n", &mem3.aPool[i], (size/4)*8-8);
+ }else{
+ fprintf(out, "%p %6d bytes free%s\n", &mem3.aPool[i], (size/4)*8-8,
+ i==mem3.iMaster ? " **master**" : "");
+ }
+ }
+ for(i=0; i0; j=mem3.aPool[j].u.list.next){
+ fprintf(out, " %p(%d)", &mem3.aPool[j],
+ (mem3.aPool[j-1].u.hdr.size4x/4)*8-8);
+ }
+ fprintf(out, "\n");
+ }
+ for(i=0; i0; j=mem3.aPool[j].u.list.next){
+ fprintf(out, " %p(%d)", &mem3.aPool[j],
+ (mem3.aPool[j-1].u.hdr.size4x/4)*8-8);
+ }
+ fprintf(out, "\n");
+ }
+ fprintf(out, "master=%d\n", mem3.iMaster);
+ fprintf(out, "nowUsed=%d\n", mem3.nPool*8 - mem3.szMaster*8);
+ fprintf(out, "mxUsed=%d\n", mem3.nPool*8 - mem3.mnMaster*8);
+ sqlite3_mutex_leave(mem3.mutex);
+ if( out==stdout ){
+ fflush(stdout);
+ }else{
+ fclose(out);
+ }
+#else
+ UNUSED_PARAMETER(zFilename);
+#endif
+}
+
+/*
+** This routine is the only routine in this file with external
+** linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file. The
+** arguments specify the block of memory to manage.
+**
+** This routine is only called by sqlite3_config(), and therefore
+** is not required to be threadsafe (it is not).
+*/
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys3(void){
+ static const sqlite3_mem_methods mempoolMethods = {
+ memsys3Malloc,
+ memsys3Free,
+ memsys3Realloc,
+ memsys3Size,
+ memsys3Roundup,
+ memsys3Init,
+ memsys3Shutdown,
+ 0
+ };
+ return &mempoolMethods;
+}
+
+#endif /* SQLITE_ENABLE_MEMSYS3 */
+
+/************** End of mem3.c ************************************************/
+/************** Begin file mem5.c ********************************************/
+/*
+** 2007 October 14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement a memory
+** allocation subsystem for use by SQLite.
+**
+** This version of the memory allocation subsystem omits all
+** use of malloc(). The application gives SQLite a block of memory
+** before calling sqlite3_initialize() from which allocations
+** are made and returned by the xMalloc() and xRealloc()
+** implementations. Once sqlite3_initialize() has been called,
+** the amount of memory available to SQLite is fixed and cannot
+** be changed.
+**
+** This version of the memory allocation subsystem is included
+** in the build only if SQLITE_ENABLE_MEMSYS5 is defined.
+**
+** This memory allocator uses the following algorithm:
+**
+** 1. All memory allocation sizes are rounded up to a power of 2.
+**
+** 2. If two adjacent free blocks are the halves of a larger block,
+** then the two blocks are coalesced into the single larger block.
+**
+** 3. New memory is allocated from the first available free block.
+**
+** This algorithm is described in: J. M. Robson. "Bounds for Some Functions
+** Concerning Dynamic Storage Allocation". Journal of the Association for
+** Computing Machinery, Volume 21, Number 8, July 1974, pages 491-499.
+**
+** Let n be the size of the largest allocation divided by the minimum
+** allocation size (after rounding all sizes up to a power of 2.) Let M
+** be the maximum amount of memory ever outstanding at one time. Let
+** N be the total amount of memory available for allocation. Robson
+** proved that this memory allocator will never breakdown due to
+** fragmentation as long as the following constraint holds:
+**
+** N >= M*(1 + log2(n)/2) - n + 1
+**
+** The sqlite3_status() logic tracks the maximum values of n and M so
+** that an application can, at any time, verify this constraint.
+*/
+/* #include "sqliteInt.h" */
+
+/*
+** This version of the memory allocator is used only when
+** SQLITE_ENABLE_MEMSYS5 is defined.
+*/
+#ifdef SQLITE_ENABLE_MEMSYS5
+
+/*
+** A minimum allocation is an instance of the following structure.
+** Larger allocations are an array of these structures where the
+** size of the array is a power of 2.
+**
+** The size of this object must be a power of two. That fact is
+** verified in memsys5Init().
+*/
+typedef struct Mem5Link Mem5Link;
+struct Mem5Link {
+ int next; /* Index of next free chunk */
+ int prev; /* Index of previous free chunk */
+};
+
+/*
+** Maximum size of any allocation is ((1<=0 && i=0 && iLogsize<=LOGMAX );
+ assert( (mem5.aCtrl[i] & CTRL_LOGSIZE)==iLogsize );
+
+ next = MEM5LINK(i)->next;
+ prev = MEM5LINK(i)->prev;
+ if( prev<0 ){
+ mem5.aiFreelist[iLogsize] = next;
+ }else{
+ MEM5LINK(prev)->next = next;
+ }
+ if( next>=0 ){
+ MEM5LINK(next)->prev = prev;
+ }
+}
+
+/*
+** Link the chunk at mem5.aPool[i] so that is on the iLogsize
+** free list.
+*/
+static void memsys5Link(int i, int iLogsize){
+ int x;
+ assert( sqlite3_mutex_held(mem5.mutex) );
+ assert( i>=0 && i=0 && iLogsize<=LOGMAX );
+ assert( (mem5.aCtrl[i] & CTRL_LOGSIZE)==iLogsize );
+
+ x = MEM5LINK(i)->next = mem5.aiFreelist[iLogsize];
+ MEM5LINK(i)->prev = -1;
+ if( x>=0 ){
+ assert( xprev = i;
+ }
+ mem5.aiFreelist[iLogsize] = i;
+}
+
+/*
+** Obtain or release the mutex needed to access global data structures.
+*/
+static void memsys5Enter(void){
+ sqlite3_mutex_enter(mem5.mutex);
+}
+static void memsys5Leave(void){
+ sqlite3_mutex_leave(mem5.mutex);
+}
+
+/*
+** Return the size of an outstanding allocation, in bytes.
+** This only works for chunks that are currently checked out.
+*/
+static int memsys5Size(void *p){
+ int iSize, i;
+ assert( p!=0 );
+ i = (int)(((u8 *)p-mem5.zPool)/mem5.szAtom);
+ assert( i>=0 && i0 );
+
+ /* No more than 1GiB per allocation */
+ if( nByte > 0x40000000 ) return 0;
+
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
+ /* Keep track of the maximum allocation request. Even unfulfilled
+ ** requests are counted */
+ if( (u32)nByte>mem5.maxRequest ){
+ mem5.maxRequest = nByte;
+ }
+#endif
+
+
+ /* Round nByte up to the next valid power of two */
+ for(iFullSz=mem5.szAtom,iLogsize=0; iFullSzLOGMAX ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes", nByte);
+ return 0;
+ }
+ i = mem5.aiFreelist[iBin];
+ memsys5Unlink(i, iBin);
+ while( iBin>iLogsize ){
+ int newSize;
+
+ iBin--;
+ newSize = 1 << iBin;
+ mem5.aCtrl[i+newSize] = CTRL_FREE | iBin;
+ memsys5Link(i+newSize, iBin);
+ }
+ mem5.aCtrl[i] = iLogsize;
+
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
+ /* Update allocator performance statistics. */
+ mem5.nAlloc++;
+ mem5.totalAlloc += iFullSz;
+ mem5.totalExcess += iFullSz - nByte;
+ mem5.currentCount++;
+ mem5.currentOut += iFullSz;
+ if( mem5.maxCount=0 && iBlock0 );
+ assert( mem5.currentOut>=(size*mem5.szAtom) );
+ mem5.currentCount--;
+ mem5.currentOut -= size*mem5.szAtom;
+ assert( mem5.currentOut>0 || mem5.currentCount==0 );
+ assert( mem5.currentCount>0 || mem5.currentOut==0 );
+#endif
+
+ mem5.aCtrl[iBlock] = CTRL_FREE | iLogsize;
+ while( ALWAYS(iLogsize>iLogsize) & 1 ){
+ iBuddy = iBlock - size;
+ assert( iBuddy>=0 );
+ }else{
+ iBuddy = iBlock + size;
+ if( iBuddy>=mem5.nBlock ) break;
+ }
+ if( mem5.aCtrl[iBuddy]!=(CTRL_FREE | iLogsize) ) break;
+ memsys5Unlink(iBuddy, iLogsize);
+ iLogsize++;
+ if( iBuddy0 ){
+ memsys5Enter();
+ p = memsys5MallocUnsafe(nBytes);
+ memsys5Leave();
+ }
+ return (void*)p;
+}
+
+/*
+** Free memory.
+**
+** The outer layer memory allocator prevents this routine from
+** being called with pPrior==0.
+*/
+static void memsys5Free(void *pPrior){
+ assert( pPrior!=0 );
+ memsys5Enter();
+ memsys5FreeUnsafe(pPrior);
+ memsys5Leave();
+}
+
+/*
+** Change the size of an existing memory allocation.
+**
+** The outer layer memory allocator prevents this routine from
+** being called with pPrior==0.
+**
+** nBytes is always a value obtained from a prior call to
+** memsys5Round(). Hence nBytes is always a non-negative power
+** of two. If nBytes==0 that means that an oversize allocation
+** (an allocation larger than 0x40000000) was requested and this
+** routine should return 0 without freeing pPrior.
+*/
+static void *memsys5Realloc(void *pPrior, int nBytes){
+ int nOld;
+ void *p;
+ assert( pPrior!=0 );
+ assert( (nBytes&(nBytes-1))==0 ); /* EV: R-46199-30249 */
+ assert( nBytes>=0 );
+ if( nBytes==0 ){
+ return 0;
+ }
+ nOld = memsys5Size(pPrior);
+ if( nBytes<=nOld ){
+ return pPrior;
+ }
+ p = memsys5Malloc(nBytes);
+ if( p ){
+ memcpy(p, pPrior, nOld);
+ memsys5Free(pPrior);
+ }
+ return p;
+}
+
+/*
+** Round up a request size to the next valid allocation size. If
+** the allocation is too large to be handled by this allocation system,
+** return 0.
+**
+** All allocations must be a power of two and must be expressed by a
+** 32-bit signed integer. Hence the largest allocation is 0x40000000
+** or 1073741824 bytes.
+*/
+static int memsys5Roundup(int n){
+ int iFullSz;
+ if( n > 0x40000000 ) return 0;
+ for(iFullSz=mem5.szAtom; iFullSz 0
+** memsys5Log(2) -> 1
+** memsys5Log(4) -> 2
+** memsys5Log(5) -> 3
+** memsys5Log(8) -> 3
+** memsys5Log(9) -> 4
+*/
+static int memsys5Log(int iValue){
+ int iLog;
+ for(iLog=0; (iLog<(int)((sizeof(int)*8)-1)) && (1<mem5.szAtom ){
+ mem5.szAtom = mem5.szAtom << 1;
+ }
+
+ mem5.nBlock = (nByte / (mem5.szAtom+sizeof(u8)));
+ mem5.zPool = zByte;
+ mem5.aCtrl = (u8 *)&mem5.zPool[mem5.nBlock*mem5.szAtom];
+
+ for(ii=0; ii<=LOGMAX; ii++){
+ mem5.aiFreelist[ii] = -1;
+ }
+
+ iOffset = 0;
+ for(ii=LOGMAX; ii>=0; ii--){
+ int nAlloc = (1<mem5.nBlock);
+ }
+
+ /* If a mutex is required for normal operation, allocate one */
+ if( sqlite3GlobalConfig.bMemstat==0 ){
+ mem5.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+ }
+
+ return SQLITE_OK;
+}
+
+/*
+** Deinitialize this module.
+*/
+static void memsys5Shutdown(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ mem5.mutex = 0;
+ return;
+}
+
+#ifdef SQLITE_TEST
+/*
+** Open the file indicated and write a log of all unfreed memory
+** allocations into that log.
+*/
+SQLITE_PRIVATE void sqlite3Memsys5Dump(const char *zFilename){
+ FILE *out;
+ int i, j, n;
+ int nMinLog;
+
+ if( zFilename==0 || zFilename[0]==0 ){
+ out = stdout;
+ }else{
+ out = fopen(zFilename, "w");
+ if( out==0 ){
+ fprintf(stderr, "** Unable to output memory debug output log: %s **\n",
+ zFilename);
+ return;
+ }
+ }
+ memsys5Enter();
+ nMinLog = memsys5Log(mem5.szAtom);
+ for(i=0; i<=LOGMAX && i+nMinLog<32; i++){
+ for(n=0, j=mem5.aiFreelist[i]; j>=0; j = MEM5LINK(j)->next, n++){}
+ fprintf(out, "freelist items of size %d: %d\n", mem5.szAtom << i, n);
+ }
+ fprintf(out, "mem5.nAlloc = %llu\n", mem5.nAlloc);
+ fprintf(out, "mem5.totalAlloc = %llu\n", mem5.totalAlloc);
+ fprintf(out, "mem5.totalExcess = %llu\n", mem5.totalExcess);
+ fprintf(out, "mem5.currentOut = %u\n", mem5.currentOut);
+ fprintf(out, "mem5.currentCount = %u\n", mem5.currentCount);
+ fprintf(out, "mem5.maxOut = %u\n", mem5.maxOut);
+ fprintf(out, "mem5.maxCount = %u\n", mem5.maxCount);
+ fprintf(out, "mem5.maxRequest = %u\n", mem5.maxRequest);
+ memsys5Leave();
+ if( out==stdout ){
+ fflush(stdout);
+ }else{
+ fclose(out);
+ }
+}
+#endif
+
+/*
+** This routine is the only routine in this file with external
+** linkage. It returns a pointer to a static sqlite3_mem_methods
+** struct populated with the memsys5 methods.
+*/
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void){
+ static const sqlite3_mem_methods memsys5Methods = {
+ memsys5Malloc,
+ memsys5Free,
+ memsys5Realloc,
+ memsys5Size,
+ memsys5Roundup,
+ memsys5Init,
+ memsys5Shutdown,
+ 0
+ };
+ return &memsys5Methods;
+}
+
+#endif /* SQLITE_ENABLE_MEMSYS5 */
+
+/************** End of mem5.c ************************************************/
+/************** Begin file mutex.c *******************************************/
+/*
+** 2007 August 14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes.
+**
+** This file contains code that is common across all mutex implementations.
+*/
+/* #include "sqliteInt.h" */
+
+#if defined(SQLITE_DEBUG) && !defined(SQLITE_MUTEX_OMIT)
+/*
+** For debugging purposes, record when the mutex subsystem is initialized
+** and uninitialized so that we can assert() if there is an attempt to
+** allocate a mutex while the system is uninitialized.
+*/
+static SQLITE_WSD int mutexIsInit = 0;
+#endif /* SQLITE_DEBUG && !defined(SQLITE_MUTEX_OMIT) */
+
+
+#ifndef SQLITE_MUTEX_OMIT
+
+#ifdef SQLITE_ENABLE_MULTITHREADED_CHECKS
+/*
+** This block (enclosed by SQLITE_ENABLE_MULTITHREADED_CHECKS) contains
+** the implementation of a wrapper around the system default mutex
+** implementation (sqlite3DefaultMutex()).
+**
+** Most calls are passed directly through to the underlying default
+** mutex implementation. Except, if a mutex is configured by calling
+** sqlite3MutexWarnOnContention() on it, then if contention is ever
+** encountered within xMutexEnter() a warning is emitted via sqlite3_log().
+**
+** This type of mutex is used as the database handle mutex when testing
+** apps that usually use SQLITE_CONFIG_MULTITHREAD mode.
+*/
+
+/*
+** Type for all mutexes used when SQLITE_ENABLE_MULTITHREADED_CHECKS
+** is defined. Variable CheckMutex.mutex is a pointer to the real mutex
+** allocated by the system mutex implementation. Variable iType is usually set
+** to the type of mutex requested - SQLITE_MUTEX_RECURSIVE, SQLITE_MUTEX_FAST
+** or one of the static mutex identifiers. Or, if this is a recursive mutex
+** that has been configured using sqlite3MutexWarnOnContention(), it is
+** set to SQLITE_MUTEX_WARNONCONTENTION.
+*/
+typedef struct CheckMutex CheckMutex;
+struct CheckMutex {
+ int iType;
+ sqlite3_mutex *mutex;
+};
+
+#define SQLITE_MUTEX_WARNONCONTENTION (-1)
+
+/*
+** Pointer to real mutex methods object used by the CheckMutex
+** implementation. Set by checkMutexInit().
+*/
+static SQLITE_WSD const sqlite3_mutex_methods *pGlobalMutexMethods;
+
+#ifdef SQLITE_DEBUG
+static int checkMutexHeld(sqlite3_mutex *p){
+ return pGlobalMutexMethods->xMutexHeld(((CheckMutex*)p)->mutex);
+}
+static int checkMutexNotheld(sqlite3_mutex *p){
+ return pGlobalMutexMethods->xMutexNotheld(((CheckMutex*)p)->mutex);
+}
+#endif
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static int checkMutexInit(void){
+ pGlobalMutexMethods = sqlite3DefaultMutex();
+ return SQLITE_OK;
+}
+static int checkMutexEnd(void){
+ pGlobalMutexMethods = 0;
+ return SQLITE_OK;
+}
+
+/*
+** Allocate a mutex.
+*/
+static sqlite3_mutex *checkMutexAlloc(int iType){
+ static CheckMutex staticMutexes[] = {
+ {2, 0}, {3, 0}, {4, 0}, {5, 0},
+ {6, 0}, {7, 0}, {8, 0}, {9, 0},
+ {10, 0}, {11, 0}, {12, 0}, {13, 0}
+ };
+ CheckMutex *p = 0;
+
+ assert( SQLITE_MUTEX_RECURSIVE==1 && SQLITE_MUTEX_FAST==0 );
+ if( iType<2 ){
+ p = sqlite3MallocZero(sizeof(CheckMutex));
+ if( p==0 ) return 0;
+ p->iType = iType;
+ }else{
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( iType-2>=ArraySize(staticMutexes) ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+ p = &staticMutexes[iType-2];
+ }
+
+ if( p->mutex==0 ){
+ p->mutex = pGlobalMutexMethods->xMutexAlloc(iType);
+ if( p->mutex==0 ){
+ if( iType<2 ){
+ sqlite3_free(p);
+ }
+ p = 0;
+ }
+ }
+
+ return (sqlite3_mutex*)p;
+}
+
+/*
+** Free a mutex.
+*/
+static void checkMutexFree(sqlite3_mutex *p){
+ assert( SQLITE_MUTEX_RECURSIVE<2 );
+ assert( SQLITE_MUTEX_FAST<2 );
+ assert( SQLITE_MUTEX_WARNONCONTENTION<2 );
+
+#if SQLITE_ENABLE_API_ARMOR
+ if( ((CheckMutex*)p)->iType<2 )
+#endif
+ {
+ CheckMutex *pCheck = (CheckMutex*)p;
+ pGlobalMutexMethods->xMutexFree(pCheck->mutex);
+ sqlite3_free(pCheck);
+ }
+#ifdef SQLITE_ENABLE_API_ARMOR
+ else{
+ (void)SQLITE_MISUSE_BKPT;
+ }
+#endif
+}
+
+/*
+** Enter the mutex.
+*/
+static void checkMutexEnter(sqlite3_mutex *p){
+ CheckMutex *pCheck = (CheckMutex*)p;
+ if( pCheck->iType==SQLITE_MUTEX_WARNONCONTENTION ){
+ if( SQLITE_OK==pGlobalMutexMethods->xMutexTry(pCheck->mutex) ){
+ return;
+ }
+ sqlite3_log(SQLITE_MISUSE,
+ "illegal multi-threaded access to database connection"
+ );
+ }
+ pGlobalMutexMethods->xMutexEnter(pCheck->mutex);
+}
+
+/*
+** Enter the mutex (do not block).
+*/
+static int checkMutexTry(sqlite3_mutex *p){
+ CheckMutex *pCheck = (CheckMutex*)p;
+ return pGlobalMutexMethods->xMutexTry(pCheck->mutex);
+}
+
+/*
+** Leave the mutex.
+*/
+static void checkMutexLeave(sqlite3_mutex *p){
+ CheckMutex *pCheck = (CheckMutex*)p;
+ pGlobalMutexMethods->xMutexLeave(pCheck->mutex);
+}
+
+sqlite3_mutex_methods const *multiThreadedCheckMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ checkMutexInit,
+ checkMutexEnd,
+ checkMutexAlloc,
+ checkMutexFree,
+ checkMutexEnter,
+ checkMutexTry,
+ checkMutexLeave,
+#ifdef SQLITE_DEBUG
+ checkMutexHeld,
+ checkMutexNotheld
+#else
+ 0,
+ 0
+#endif
+ };
+ return &sMutex;
+}
+
+/*
+** Mark the SQLITE_MUTEX_RECURSIVE mutex passed as the only argument as
+** one on which there should be no contention.
+*/
+SQLITE_PRIVATE void sqlite3MutexWarnOnContention(sqlite3_mutex *p){
+ if( sqlite3GlobalConfig.mutex.xMutexAlloc==checkMutexAlloc ){
+ CheckMutex *pCheck = (CheckMutex*)p;
+ assert( pCheck->iType==SQLITE_MUTEX_RECURSIVE );
+ pCheck->iType = SQLITE_MUTEX_WARNONCONTENTION;
+ }
+}
+#endif /* ifdef SQLITE_ENABLE_MULTITHREADED_CHECKS */
+
+/*
+** Initialize the mutex system.
+*/
+SQLITE_PRIVATE int sqlite3MutexInit(void){
+ int rc = SQLITE_OK;
+ if( !sqlite3GlobalConfig.mutex.xMutexAlloc ){
+ /* If the xMutexAlloc method has not been set, then the user did not
+ ** install a mutex implementation via sqlite3_config() prior to
+ ** sqlite3_initialize() being called. This block copies pointers to
+ ** the default implementation into the sqlite3GlobalConfig structure.
+ */
+ sqlite3_mutex_methods const *pFrom;
+ sqlite3_mutex_methods *pTo = &sqlite3GlobalConfig.mutex;
+
+ if( sqlite3GlobalConfig.bCoreMutex ){
+#ifdef SQLITE_ENABLE_MULTITHREADED_CHECKS
+ pFrom = multiThreadedCheckMutex();
+#else
+ pFrom = sqlite3DefaultMutex();
+#endif
+ }else{
+ pFrom = sqlite3NoopMutex();
+ }
+ pTo->xMutexInit = pFrom->xMutexInit;
+ pTo->xMutexEnd = pFrom->xMutexEnd;
+ pTo->xMutexFree = pFrom->xMutexFree;
+ pTo->xMutexEnter = pFrom->xMutexEnter;
+ pTo->xMutexTry = pFrom->xMutexTry;
+ pTo->xMutexLeave = pFrom->xMutexLeave;
+ pTo->xMutexHeld = pFrom->xMutexHeld;
+ pTo->xMutexNotheld = pFrom->xMutexNotheld;
+ sqlite3MemoryBarrier();
+ pTo->xMutexAlloc = pFrom->xMutexAlloc;
+ }
+ assert( sqlite3GlobalConfig.mutex.xMutexInit );
+ rc = sqlite3GlobalConfig.mutex.xMutexInit();
+
+#ifdef SQLITE_DEBUG
+ GLOBAL(int, mutexIsInit) = 1;
+#endif
+
+ return rc;
+}
+
+/*
+** Shutdown the mutex system. This call frees resources allocated by
+** sqlite3MutexInit().
+*/
+SQLITE_PRIVATE int sqlite3MutexEnd(void){
+ int rc = SQLITE_OK;
+ if( sqlite3GlobalConfig.mutex.xMutexEnd ){
+ rc = sqlite3GlobalConfig.mutex.xMutexEnd();
+ }
+
+#ifdef SQLITE_DEBUG
+ GLOBAL(int, mutexIsInit) = 0;
+#endif
+
+ return rc;
+}
+
+/*
+** Retrieve a pointer to a static mutex or allocate a new dynamic one.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int id){
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( id<=SQLITE_MUTEX_RECURSIVE && sqlite3_initialize() ) return 0;
+ if( id>SQLITE_MUTEX_RECURSIVE && sqlite3MutexInit() ) return 0;
+#endif
+ assert( sqlite3GlobalConfig.mutex.xMutexAlloc );
+ return sqlite3GlobalConfig.mutex.xMutexAlloc(id);
+}
+
+SQLITE_PRIVATE sqlite3_mutex *sqlite3MutexAlloc(int id){
+ if( !sqlite3GlobalConfig.bCoreMutex ){
+ return 0;
+ }
+ assert( GLOBAL(int, mutexIsInit) );
+ assert( sqlite3GlobalConfig.mutex.xMutexAlloc );
+ return sqlite3GlobalConfig.mutex.xMutexAlloc(id);
+}
+
+/*
+** Free a dynamic mutex.
+*/
+SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
+ if( p ){
+ assert( sqlite3GlobalConfig.mutex.xMutexFree );
+ sqlite3GlobalConfig.mutex.xMutexFree(p);
+ }
+}
+
+/*
+** Obtain the mutex p. If some other thread already has the mutex, block
+** until it can be obtained.
+*/
+SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex *p){
+ if( p ){
+ assert( sqlite3GlobalConfig.mutex.xMutexEnter );
+ sqlite3GlobalConfig.mutex.xMutexEnter(p);
+ }
+}
+
+/*
+** Obtain the mutex p. If successful, return SQLITE_OK. Otherwise, if another
+** thread holds the mutex and it cannot be obtained, return SQLITE_BUSY.
+*/
+SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
+ int rc = SQLITE_OK;
+ if( p ){
+ assert( sqlite3GlobalConfig.mutex.xMutexTry );
+ return sqlite3GlobalConfig.mutex.xMutexTry(p);
+ }
+ return rc;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was previously
+** entered by the same thread. The behavior is undefined if the mutex
+** is not currently entered. If a NULL pointer is passed as an argument
+** this function is a no-op.
+*/
+SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
+ if( p ){
+ assert( sqlite3GlobalConfig.mutex.xMutexLeave );
+ sqlite3GlobalConfig.mutex.xMutexLeave(p);
+ }
+}
+
+#ifndef NDEBUG
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use inside assert() statements.
+*/
+SQLITE_API int sqlite3_mutex_held(sqlite3_mutex *p){
+ assert( p==0 || sqlite3GlobalConfig.mutex.xMutexHeld );
+ return p==0 || sqlite3GlobalConfig.mutex.xMutexHeld(p);
+}
+SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
+ assert( p==0 || sqlite3GlobalConfig.mutex.xMutexNotheld );
+ return p==0 || sqlite3GlobalConfig.mutex.xMutexNotheld(p);
+}
+#endif
+
+#endif /* !defined(SQLITE_MUTEX_OMIT) */
+
+/************** End of mutex.c ***********************************************/
+/************** Begin file mutex_noop.c **************************************/
+/*
+** 2008 October 07
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes.
+**
+** This implementation in this file does not provide any mutual
+** exclusion and is thus suitable for use only in applications
+** that use SQLite in a single thread. The routines defined
+** here are place-holders. Applications can substitute working
+** mutex routines at start-time using the
+**
+** sqlite3_config(SQLITE_CONFIG_MUTEX,...)
+**
+** interface.
+**
+** If compiled with SQLITE_DEBUG, then additional logic is inserted
+** that does error checking on mutexes to make sure they are being
+** called correctly.
+*/
+/* #include "sqliteInt.h" */
+
+#ifndef SQLITE_MUTEX_OMIT
+
+#ifndef SQLITE_DEBUG
+/*
+** Stub routines for all mutex methods.
+**
+** This routines provide no mutual exclusion or error checking.
+*/
+static int noopMutexInit(void){ return SQLITE_OK; }
+static int noopMutexEnd(void){ return SQLITE_OK; }
+static sqlite3_mutex *noopMutexAlloc(int id){
+ UNUSED_PARAMETER(id);
+ return (sqlite3_mutex*)8;
+}
+static void noopMutexFree(sqlite3_mutex *p){ UNUSED_PARAMETER(p); return; }
+static void noopMutexEnter(sqlite3_mutex *p){ UNUSED_PARAMETER(p); return; }
+static int noopMutexTry(sqlite3_mutex *p){
+ UNUSED_PARAMETER(p);
+ return SQLITE_OK;
+}
+static void noopMutexLeave(sqlite3_mutex *p){ UNUSED_PARAMETER(p); return; }
+
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3NoopMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ noopMutexInit,
+ noopMutexEnd,
+ noopMutexAlloc,
+ noopMutexFree,
+ noopMutexEnter,
+ noopMutexTry,
+ noopMutexLeave,
+
+ 0,
+ 0,
+ };
+
+ return &sMutex;
+}
+#endif /* !SQLITE_DEBUG */
+
+#ifdef SQLITE_DEBUG
+/*
+** In this implementation, error checking is provided for testing
+** and debugging purposes. The mutexes still do not provide any
+** mutual exclusion.
+*/
+
+/*
+** The mutex object
+*/
+typedef struct sqlite3_debug_mutex {
+ int id; /* The mutex type */
+ int cnt; /* Number of entries without a matching leave */
+} sqlite3_debug_mutex;
+
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use inside assert() statements.
+*/
+static int debugMutexHeld(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ return p==0 || p->cnt>0;
+}
+static int debugMutexNotheld(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ return p==0 || p->cnt==0;
+}
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static int debugMutexInit(void){ return SQLITE_OK; }
+static int debugMutexEnd(void){ return SQLITE_OK; }
+
+/*
+** The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. If it returns NULL
+** that means that a mutex could not be allocated.
+*/
+static sqlite3_mutex *debugMutexAlloc(int id){
+ static sqlite3_debug_mutex aStatic[SQLITE_MUTEX_STATIC_VFS3 - 1];
+ sqlite3_debug_mutex *pNew = 0;
+ switch( id ){
+ case SQLITE_MUTEX_FAST:
+ case SQLITE_MUTEX_RECURSIVE: {
+ pNew = sqlite3Malloc(sizeof(*pNew));
+ if( pNew ){
+ pNew->id = id;
+ pNew->cnt = 0;
+ }
+ break;
+ }
+ default: {
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( id-2<0 || id-2>=ArraySize(aStatic) ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+ pNew = &aStatic[id-2];
+ pNew->id = id;
+ break;
+ }
+ }
+ return (sqlite3_mutex*)pNew;
+}
+
+/*
+** This routine deallocates a previously allocated mutex.
+*/
+static void debugMutexFree(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ assert( p->cnt==0 );
+ if( p->id==SQLITE_MUTEX_RECURSIVE || p->id==SQLITE_MUTEX_FAST ){
+ sqlite3_free(p);
+ }else{
+#ifdef SQLITE_ENABLE_API_ARMOR
+ (void)SQLITE_MISUSE_BKPT;
+#endif
+ }
+}
+
+/*
+** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex. If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY. The sqlite3_mutex_try() interface returns SQLITE_OK
+** upon successful entry. Mutexes created using SQLITE_MUTEX_RECURSIVE can
+** be entered multiple times by the same thread. In such cases the,
+** mutex must be exited an equal number of times before another thread
+** can enter. If the same thread tries to enter any other kind of mutex
+** more than once, the behavior is undefined.
+*/
+static void debugMutexEnter(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(pX) );
+ p->cnt++;
+}
+static int debugMutexTry(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(pX) );
+ p->cnt++;
+ return SQLITE_OK;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread. The behavior
+** is undefined if the mutex is not currently entered or
+** is not currently allocated. SQLite will never do either.
+*/
+static void debugMutexLeave(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ assert( debugMutexHeld(pX) );
+ p->cnt--;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(pX) );
+}
+
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3NoopMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ debugMutexInit,
+ debugMutexEnd,
+ debugMutexAlloc,
+ debugMutexFree,
+ debugMutexEnter,
+ debugMutexTry,
+ debugMutexLeave,
+
+ debugMutexHeld,
+ debugMutexNotheld
+ };
+
+ return &sMutex;
+}
+#endif /* SQLITE_DEBUG */
+
+/*
+** If compiled with SQLITE_MUTEX_NOOP, then the no-op mutex implementation
+** is used regardless of the run-time threadsafety setting.
+*/
+#ifdef SQLITE_MUTEX_NOOP
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
+ return sqlite3NoopMutex();
+}
+#endif /* defined(SQLITE_MUTEX_NOOP) */
+#endif /* !defined(SQLITE_MUTEX_OMIT) */
+
+/************** End of mutex_noop.c ******************************************/
+/************** Begin file mutex_unix.c **************************************/
+/*
+** 2007 August 28
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes for pthreads
+*/
+/* #include "sqliteInt.h" */
+
+/*
+** The code in this file is only used if we are compiling threadsafe
+** under unix with pthreads.
+**
+** Note that this implementation requires a version of pthreads that
+** supports recursive mutexes.
+*/
+#ifdef SQLITE_MUTEX_PTHREADS
+
+#include
+
+/*
+** The sqlite3_mutex.id, sqlite3_mutex.nRef, and sqlite3_mutex.owner fields
+** are necessary under two condidtions: (1) Debug builds and (2) using
+** home-grown mutexes. Encapsulate these conditions into a single #define.
+*/
+#if defined(SQLITE_DEBUG) || defined(SQLITE_HOMEGROWN_RECURSIVE_MUTEX)
+# define SQLITE_MUTEX_NREF 1
+#else
+# define SQLITE_MUTEX_NREF 0
+#endif
+
+/*
+** Each recursive mutex is an instance of the following structure.
+*/
+struct sqlite3_mutex {
+ pthread_mutex_t mutex; /* Mutex controlling the lock */
+#if SQLITE_MUTEX_NREF || defined(SQLITE_ENABLE_API_ARMOR)
+ int id; /* Mutex type */
+#endif
+#if SQLITE_MUTEX_NREF
+ volatile int nRef; /* Number of entrances */
+ volatile pthread_t owner; /* Thread that is within this mutex */
+ int trace; /* True to trace changes */
+#endif
+};
+#if SQLITE_MUTEX_NREF
+# define SQLITE3_MUTEX_INITIALIZER(id) \
+ {PTHREAD_MUTEX_INITIALIZER,id,0,(pthread_t)0,0}
+#elif defined(SQLITE_ENABLE_API_ARMOR)
+# define SQLITE3_MUTEX_INITIALIZER(id) { PTHREAD_MUTEX_INITIALIZER, id }
+#else
+#define SQLITE3_MUTEX_INITIALIZER(id) { PTHREAD_MUTEX_INITIALIZER }
+#endif
+
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use only inside assert() statements. On some platforms,
+** there might be race conditions that can cause these routines to
+** deliver incorrect results. In particular, if pthread_equal() is
+** not an atomic operation, then these routines might delivery
+** incorrect results. On most platforms, pthread_equal() is a
+** comparison of two integers and is therefore atomic. But we are
+** told that HPUX is not such a platform. If so, then these routines
+** will not always work correctly on HPUX.
+**
+** On those platforms where pthread_equal() is not atomic, SQLite
+** should be compiled without -DSQLITE_DEBUG and with -DNDEBUG to
+** make sure no assert() statements are evaluated and hence these
+** routines are never called.
+*/
+#if !defined(NDEBUG) || defined(SQLITE_DEBUG)
+static int pthreadMutexHeld(sqlite3_mutex *p){
+ return (p->nRef!=0 && pthread_equal(p->owner, pthread_self()));
+}
+static int pthreadMutexNotheld(sqlite3_mutex *p){
+ return p->nRef==0 || pthread_equal(p->owner, pthread_self())==0;
+}
+#endif
+
+/*
+** Try to provide a memory barrier operation, needed for initialization
+** and also for the implementation of xShmBarrier in the VFS in cases
+** where SQLite is compiled without mutexes.
+*/
+SQLITE_PRIVATE void sqlite3MemoryBarrier(void){
+#if defined(SQLITE_MEMORY_BARRIER)
+ SQLITE_MEMORY_BARRIER;
+#elif defined(__GNUC__) && GCC_VERSION>=4001000
+ __sync_synchronize();
+#endif
+}
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static int pthreadMutexInit(void){ return SQLITE_OK; }
+static int pthreadMutexEnd(void){ return SQLITE_OK; }
+
+/*
+** The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. If it returns NULL
+** that means that a mutex could not be allocated. SQLite
+** will unwind its stack and return an error. The argument
+** to sqlite3_mutex_alloc() is one of these integer constants:
+**
+**
+**
SQLITE_MUTEX_FAST
+**
SQLITE_MUTEX_RECURSIVE
+**
SQLITE_MUTEX_STATIC_MASTER
+**
SQLITE_MUTEX_STATIC_MEM
+**
SQLITE_MUTEX_STATIC_OPEN
+**
SQLITE_MUTEX_STATIC_PRNG
+**
SQLITE_MUTEX_STATIC_LRU
+**
SQLITE_MUTEX_STATIC_PMEM
+**
SQLITE_MUTEX_STATIC_APP1
+**
SQLITE_MUTEX_STATIC_APP2
+**
SQLITE_MUTEX_STATIC_APP3
+**
SQLITE_MUTEX_STATIC_VFS1
+**
SQLITE_MUTEX_STATIC_VFS2
+**
SQLITE_MUTEX_STATIC_VFS3
+**
+**
+** The first two constants cause sqlite3_mutex_alloc() to create
+** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
+** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
+** The mutex implementation does not need to make a distinction
+** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
+** not want to. But SQLite will only request a recursive mutex in
+** cases where it really needs one. If a faster non-recursive mutex
+** implementation is available on the host platform, the mutex subsystem
+** might return such a mutex in response to SQLITE_MUTEX_FAST.
+**
+** The other allowed parameters to sqlite3_mutex_alloc() each return
+** a pointer to a static preexisting mutex. Six static mutexes are
+** used by the current version of SQLite. Future versions of SQLite
+** may add additional static mutexes. Static mutexes are for internal
+** use by SQLite only. Applications that use SQLite mutexes should
+** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
+** SQLITE_MUTEX_RECURSIVE.
+**
+** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
+** returns a different mutex on every call. But for the static
+** mutex types, the same mutex is returned on every call that has
+** the same type number.
+*/
+static sqlite3_mutex *pthreadMutexAlloc(int iType){
+ static sqlite3_mutex staticMutexes[] = {
+ SQLITE3_MUTEX_INITIALIZER(2),
+ SQLITE3_MUTEX_INITIALIZER(3),
+ SQLITE3_MUTEX_INITIALIZER(4),
+ SQLITE3_MUTEX_INITIALIZER(5),
+ SQLITE3_MUTEX_INITIALIZER(6),
+ SQLITE3_MUTEX_INITIALIZER(7),
+ SQLITE3_MUTEX_INITIALIZER(8),
+ SQLITE3_MUTEX_INITIALIZER(9),
+ SQLITE3_MUTEX_INITIALIZER(10),
+ SQLITE3_MUTEX_INITIALIZER(11),
+ SQLITE3_MUTEX_INITIALIZER(12),
+ SQLITE3_MUTEX_INITIALIZER(13)
+ };
+ sqlite3_mutex *p;
+ switch( iType ){
+ case SQLITE_MUTEX_RECURSIVE: {
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p ){
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ /* If recursive mutexes are not available, we will have to
+ ** build our own. See below. */
+ pthread_mutex_init(&p->mutex, 0);
+#else
+ /* Use a recursive mutex if it is available */
+ pthread_mutexattr_t recursiveAttr;
+ pthread_mutexattr_init(&recursiveAttr);
+ pthread_mutexattr_settype(&recursiveAttr, PTHREAD_MUTEX_RECURSIVE);
+ pthread_mutex_init(&p->mutex, &recursiveAttr);
+ pthread_mutexattr_destroy(&recursiveAttr);
+#endif
+#if SQLITE_MUTEX_NREF || defined(SQLITE_ENABLE_API_ARMOR)
+ p->id = SQLITE_MUTEX_RECURSIVE;
+#endif
+ }
+ break;
+ }
+ case SQLITE_MUTEX_FAST: {
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p ){
+ pthread_mutex_init(&p->mutex, 0);
+#if SQLITE_MUTEX_NREF || defined(SQLITE_ENABLE_API_ARMOR)
+ p->id = SQLITE_MUTEX_FAST;
+#endif
+ }
+ break;
+ }
+ default: {
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( iType-2<0 || iType-2>=ArraySize(staticMutexes) ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+ p = &staticMutexes[iType-2];
+ break;
+ }
+ }
+#if SQLITE_MUTEX_NREF || defined(SQLITE_ENABLE_API_ARMOR)
+ assert( p==0 || p->id==iType );
+#endif
+ return p;
+}
+
+
+/*
+** This routine deallocates a previously
+** allocated mutex. SQLite is careful to deallocate every
+** mutex that it allocates.
+*/
+static void pthreadMutexFree(sqlite3_mutex *p){
+ assert( p->nRef==0 );
+#if SQLITE_ENABLE_API_ARMOR
+ if( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE )
+#endif
+ {
+ pthread_mutex_destroy(&p->mutex);
+ sqlite3_free(p);
+ }
+#ifdef SQLITE_ENABLE_API_ARMOR
+ else{
+ (void)SQLITE_MISUSE_BKPT;
+ }
+#endif
+}
+
+/*
+** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex. If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY. The sqlite3_mutex_try() interface returns SQLITE_OK
+** upon successful entry. Mutexes created using SQLITE_MUTEX_RECURSIVE can
+** be entered multiple times by the same thread. In such cases the,
+** mutex must be exited an equal number of times before another thread
+** can enter. If the same thread tries to enter any other kind of mutex
+** more than once, the behavior is undefined.
+*/
+static void pthreadMutexEnter(sqlite3_mutex *p){
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );
+
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ /* If recursive mutexes are not available, then we have to grow
+ ** our own. This implementation assumes that pthread_equal()
+ ** is atomic - that it cannot be deceived into thinking self
+ ** and p->owner are equal if p->owner changes between two values
+ ** that are not equal to self while the comparison is taking place.
+ ** This implementation also assumes a coherent cache - that
+ ** separate processes cannot read different values from the same
+ ** address at the same time. If either of these two conditions
+ ** are not met, then the mutexes will fail and problems will result.
+ */
+ {
+ pthread_t self = pthread_self();
+ if( p->nRef>0 && pthread_equal(p->owner, self) ){
+ p->nRef++;
+ }else{
+ pthread_mutex_lock(&p->mutex);
+ assert( p->nRef==0 );
+ p->owner = self;
+ p->nRef = 1;
+ }
+ }
+#else
+ /* Use the built-in recursive mutexes if they are available.
+ */
+ pthread_mutex_lock(&p->mutex);
+#if SQLITE_MUTEX_NREF
+ assert( p->nRef>0 || p->owner==0 );
+ p->owner = pthread_self();
+ p->nRef++;
+#endif
+#endif
+
+#ifdef SQLITE_DEBUG
+ if( p->trace ){
+ printf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+}
+static int pthreadMutexTry(sqlite3_mutex *p){
+ int rc;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );
+
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ /* If recursive mutexes are not available, then we have to grow
+ ** our own. This implementation assumes that pthread_equal()
+ ** is atomic - that it cannot be deceived into thinking self
+ ** and p->owner are equal if p->owner changes between two values
+ ** that are not equal to self while the comparison is taking place.
+ ** This implementation also assumes a coherent cache - that
+ ** separate processes cannot read different values from the same
+ ** address at the same time. If either of these two conditions
+ ** are not met, then the mutexes will fail and problems will result.
+ */
+ {
+ pthread_t self = pthread_self();
+ if( p->nRef>0 && pthread_equal(p->owner, self) ){
+ p->nRef++;
+ rc = SQLITE_OK;
+ }else if( pthread_mutex_trylock(&p->mutex)==0 ){
+ assert( p->nRef==0 );
+ p->owner = self;
+ p->nRef = 1;
+ rc = SQLITE_OK;
+ }else{
+ rc = SQLITE_BUSY;
+ }
+ }
+#else
+ /* Use the built-in recursive mutexes if they are available.
+ */
+ if( pthread_mutex_trylock(&p->mutex)==0 ){
+#if SQLITE_MUTEX_NREF
+ p->owner = pthread_self();
+ p->nRef++;
+#endif
+ rc = SQLITE_OK;
+ }else{
+ rc = SQLITE_BUSY;
+ }
+#endif
+
+#ifdef SQLITE_DEBUG
+ if( rc==SQLITE_OK && p->trace ){
+ printf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+ return rc;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread. The behavior
+** is undefined if the mutex is not currently entered or
+** is not currently allocated. SQLite will never do either.
+*/
+static void pthreadMutexLeave(sqlite3_mutex *p){
+ assert( pthreadMutexHeld(p) );
+#if SQLITE_MUTEX_NREF
+ p->nRef--;
+ if( p->nRef==0 ) p->owner = 0;
+#endif
+ assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
+
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ if( p->nRef==0 ){
+ pthread_mutex_unlock(&p->mutex);
+ }
+#else
+ pthread_mutex_unlock(&p->mutex);
+#endif
+
+#ifdef SQLITE_DEBUG
+ if( p->trace ){
+ printf("leave mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+}
+
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ pthreadMutexInit,
+ pthreadMutexEnd,
+ pthreadMutexAlloc,
+ pthreadMutexFree,
+ pthreadMutexEnter,
+ pthreadMutexTry,
+ pthreadMutexLeave,
+#ifdef SQLITE_DEBUG
+ pthreadMutexHeld,
+ pthreadMutexNotheld
+#else
+ 0,
+ 0
+#endif
+ };
+
+ return &sMutex;
+}
+
+#endif /* SQLITE_MUTEX_PTHREADS */
+
+/************** End of mutex_unix.c ******************************************/
+/************** Begin file mutex_w32.c ***************************************/
+/*
+** 2007 August 14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes for Win32.
+*/
+/* #include "sqliteInt.h" */
+
+#if SQLITE_OS_WIN
+/*
+** Include code that is common to all os_*.c files
+*/
+/************** Include os_common.h in the middle of mutex_w32.c *************/
+/************** Begin file os_common.h ***************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains macros and a little bit of code that is common to
+** all of the platform-specific files (os_*.c) and is #included into those
+** files.
+**
+** This file should be #included by the os_*.c files only. It is not a
+** general purpose header file.
+*/
+#ifndef _OS_COMMON_H_
+#define _OS_COMMON_H_
+
+/*
+** At least two bugs have slipped in because we changed the MEMORY_DEBUG
+** macro to SQLITE_DEBUG and some older makefiles have not yet made the
+** switch. The following code should catch this problem at compile-time.
+*/
+#ifdef MEMORY_DEBUG
+# error "The MEMORY_DEBUG macro is obsolete. Use SQLITE_DEBUG instead."
+#endif
+
+/*
+** Macros for performance tracing. Normally turned off. Only works
+** on i486 hardware.
+*/
+#ifdef SQLITE_PERFORMANCE_TRACE
+
+/*
+** hwtime.h contains inline assembler code for implementing
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of os_common.h ****************/
+/************** Begin file hwtime.h ******************************************/
+/*
+** 2008 May 27
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
+*/
+#ifndef SQLITE_HWTIME_H
+#define SQLITE_HWTIME_H
+
+/*
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value. This can be used for high-res
+** profiling.
+*/
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+ (defined(i386) || defined(__i386__) || defined(_M_IX86))
+
+ #if defined(__GNUC__)
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned int lo, hi;
+ __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+ return (sqlite_uint64)hi << 32 | lo;
+ }
+
+ #elif defined(_MSC_VER)
+
+ __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+ __asm {
+ rdtsc
+ ret ; return value at EDX:EAX
+ }
+ }
+
+ #endif
+
+#elif (defined(__GNUC__) && defined(__x86_64__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long val;
+ __asm__ __volatile__ ("rdtsc" : "=A" (val));
+ return val;
+ }
+
+#elif (defined(__GNUC__) && defined(__ppc__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long long retval;
+ unsigned long junk;
+ __asm__ __volatile__ ("\n\
+ 1: mftbu %1\n\
+ mftb %L0\n\
+ mftbu %0\n\
+ cmpw %0,%1\n\
+ bne 1b"
+ : "=r" (retval), "=r" (junk));
+ return retval;
+ }
+
+#else
+
+ #error Need implementation of sqlite3Hwtime() for your platform.
+
+ /*
+ ** To compile without implementing sqlite3Hwtime() for your platform,
+ ** you can remove the above #error and use the following
+ ** stub function. You will lose timing support for many
+ ** of the debugging and testing utilities, but it should at
+ ** least compile and run.
+ */
+SQLITE_PRIVATE sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
+
+#endif
+
+#endif /* !defined(SQLITE_HWTIME_H) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in os_common.h ******************/
+
+static sqlite_uint64 g_start;
+static sqlite_uint64 g_elapsed;
+#define TIMER_START g_start=sqlite3Hwtime()
+#define TIMER_END g_elapsed=sqlite3Hwtime()-g_start
+#define TIMER_ELAPSED g_elapsed
+#else
+#define TIMER_START
+#define TIMER_END
+#define TIMER_ELAPSED ((sqlite_uint64)0)
+#endif
+
+/*
+** If we compile with the SQLITE_TEST macro set, then the following block
+** of code will give us the ability to simulate a disk I/O error. This
+** is used for testing the I/O recovery logic.
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API extern int sqlite3_io_error_hit;
+SQLITE_API extern int sqlite3_io_error_hardhit;
+SQLITE_API extern int sqlite3_io_error_pending;
+SQLITE_API extern int sqlite3_io_error_persist;
+SQLITE_API extern int sqlite3_io_error_benign;
+SQLITE_API extern int sqlite3_diskfull_pending;
+SQLITE_API extern int sqlite3_diskfull;
+#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
+#define SimulateIOError(CODE) \
+ if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
+ || sqlite3_io_error_pending-- == 1 ) \
+ { local_ioerr(); CODE; }
+static void local_ioerr(){
+ IOTRACE(("IOERR\n"));
+ sqlite3_io_error_hit++;
+ if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
+}
+#define SimulateDiskfullError(CODE) \
+ if( sqlite3_diskfull_pending ){ \
+ if( sqlite3_diskfull_pending == 1 ){ \
+ local_ioerr(); \
+ sqlite3_diskfull = 1; \
+ sqlite3_io_error_hit = 1; \
+ CODE; \
+ }else{ \
+ sqlite3_diskfull_pending--; \
+ } \
+ }
+#else
+#define SimulateIOErrorBenign(X)
+#define SimulateIOError(A)
+#define SimulateDiskfullError(A)
+#endif /* defined(SQLITE_TEST) */
+
+/*
+** When testing, keep a count of the number of open files.
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API extern int sqlite3_open_file_count;
+#define OpenCounter(X) sqlite3_open_file_count+=(X)
+#else
+#define OpenCounter(X)
+#endif /* defined(SQLITE_TEST) */
+
+#endif /* !defined(_OS_COMMON_H_) */
+
+/************** End of os_common.h *******************************************/
+/************** Continuing where we left off in mutex_w32.c ******************/
+
+/*
+** Include the header file for the Windows VFS.
+*/
+/************** Include os_win.h in the middle of mutex_w32.c ****************/
+/************** Begin file os_win.h ******************************************/
+/*
+** 2013 November 25
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains code that is specific to Windows.
+*/
+#ifndef SQLITE_OS_WIN_H
+#define SQLITE_OS_WIN_H
+
+/*
+** Include the primary Windows SDK header file.
+*/
+#include "windows.h"
+
+#ifdef __CYGWIN__
+# include
+# include /* amalgamator: dontcache */
+#endif
+
+/*
+** Determine if we are dealing with Windows NT.
+**
+** We ought to be able to determine if we are compiling for Windows 9x or
+** Windows NT using the _WIN32_WINNT macro as follows:
+**
+** #if defined(_WIN32_WINNT)
+** # define SQLITE_OS_WINNT 1
+** #else
+** # define SQLITE_OS_WINNT 0
+** #endif
+**
+** However, Visual Studio 2005 does not set _WIN32_WINNT by default, as
+** it ought to, so the above test does not work. We'll just assume that
+** everything is Windows NT unless the programmer explicitly says otherwise
+** by setting SQLITE_OS_WINNT to 0.
+*/
+#if SQLITE_OS_WIN && !defined(SQLITE_OS_WINNT)
+# define SQLITE_OS_WINNT 1
+#endif
+
+/*
+** Determine if we are dealing with Windows CE - which has a much reduced
+** API.
+*/
+#if defined(_WIN32_WCE)
+# define SQLITE_OS_WINCE 1
+#else
+# define SQLITE_OS_WINCE 0
+#endif
+
+/*
+** Determine if we are dealing with WinRT, which provides only a subset of
+** the full Win32 API.
+*/
+#if !defined(SQLITE_OS_WINRT)
+# define SQLITE_OS_WINRT 0
+#endif
+
+/*
+** For WinCE, some API function parameters do not appear to be declared as
+** volatile.
+*/
+#if SQLITE_OS_WINCE
+# define SQLITE_WIN32_VOLATILE
+#else
+# define SQLITE_WIN32_VOLATILE volatile
+#endif
+
+/*
+** For some Windows sub-platforms, the _beginthreadex() / _endthreadex()
+** functions are not available (e.g. those not using MSVC, Cygwin, etc).
+*/
+#if SQLITE_OS_WIN && !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
+ SQLITE_THREADSAFE>0 && !defined(__CYGWIN__)
+# define SQLITE_OS_WIN_THREADS 1
+#else
+# define SQLITE_OS_WIN_THREADS 0
+#endif
+
+#endif /* SQLITE_OS_WIN_H */
+
+/************** End of os_win.h **********************************************/
+/************** Continuing where we left off in mutex_w32.c ******************/
+#endif
+
+/*
+** The code in this file is only used if we are compiling multithreaded
+** on a Win32 system.
+*/
+#ifdef SQLITE_MUTEX_W32
+
+/*
+** Each recursive mutex is an instance of the following structure.
+*/
+struct sqlite3_mutex {
+ CRITICAL_SECTION mutex; /* Mutex controlling the lock */
+ int id; /* Mutex type */
+#ifdef SQLITE_DEBUG
+ volatile int nRef; /* Number of enterances */
+ volatile DWORD owner; /* Thread holding this mutex */
+ volatile LONG trace; /* True to trace changes */
+#endif
+};
+
+/*
+** These are the initializer values used when declaring a "static" mutex
+** on Win32. It should be noted that all mutexes require initialization
+** on the Win32 platform.
+*/
+#define SQLITE_W32_MUTEX_INITIALIZER { 0 }
+
+#ifdef SQLITE_DEBUG
+#define SQLITE3_MUTEX_INITIALIZER(id) { SQLITE_W32_MUTEX_INITIALIZER, id, \
+ 0L, (DWORD)0, 0 }
+#else
+#define SQLITE3_MUTEX_INITIALIZER(id) { SQLITE_W32_MUTEX_INITIALIZER, id }
+#endif
+
+#ifdef SQLITE_DEBUG
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use only inside assert() statements.
+*/
+static int winMutexHeld(sqlite3_mutex *p){
+ return p->nRef!=0 && p->owner==GetCurrentThreadId();
+}
+
+static int winMutexNotheld2(sqlite3_mutex *p, DWORD tid){
+ return p->nRef==0 || p->owner!=tid;
+}
+
+static int winMutexNotheld(sqlite3_mutex *p){
+ DWORD tid = GetCurrentThreadId();
+ return winMutexNotheld2(p, tid);
+}
+#endif
+
+/*
+** Try to provide a memory barrier operation, needed for initialization
+** and also for the xShmBarrier method of the VFS in cases when SQLite is
+** compiled without mutexes (SQLITE_THREADSAFE=0).
+*/
+SQLITE_PRIVATE void sqlite3MemoryBarrier(void){
+#if defined(SQLITE_MEMORY_BARRIER)
+ SQLITE_MEMORY_BARRIER;
+#elif defined(__GNUC__)
+ __sync_synchronize();
+#elif MSVC_VERSION>=1300
+ _ReadWriteBarrier();
+#elif defined(MemoryBarrier)
+ MemoryBarrier();
+#endif
+}
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static sqlite3_mutex winMutex_staticMutexes[] = {
+ SQLITE3_MUTEX_INITIALIZER(2),
+ SQLITE3_MUTEX_INITIALIZER(3),
+ SQLITE3_MUTEX_INITIALIZER(4),
+ SQLITE3_MUTEX_INITIALIZER(5),
+ SQLITE3_MUTEX_INITIALIZER(6),
+ SQLITE3_MUTEX_INITIALIZER(7),
+ SQLITE3_MUTEX_INITIALIZER(8),
+ SQLITE3_MUTEX_INITIALIZER(9),
+ SQLITE3_MUTEX_INITIALIZER(10),
+ SQLITE3_MUTEX_INITIALIZER(11),
+ SQLITE3_MUTEX_INITIALIZER(12),
+ SQLITE3_MUTEX_INITIALIZER(13)
+};
+
+static int winMutex_isInit = 0;
+static int winMutex_isNt = -1; /* <0 means "need to query" */
+
+/* As the winMutexInit() and winMutexEnd() functions are called as part
+** of the sqlite3_initialize() and sqlite3_shutdown() processing, the
+** "interlocked" magic used here is probably not strictly necessary.
+*/
+static LONG SQLITE_WIN32_VOLATILE winMutex_lock = 0;
+
+SQLITE_API int sqlite3_win32_is_nt(void); /* os_win.c */
+SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */
+
+static int winMutexInit(void){
+ /* The first to increment to 1 does actual initialization */
+ if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
+ int i;
+ for(i=0; i
+**
SQLITE_MUTEX_FAST
+**
SQLITE_MUTEX_RECURSIVE
+**
SQLITE_MUTEX_STATIC_MASTER
+**
SQLITE_MUTEX_STATIC_MEM
+**
SQLITE_MUTEX_STATIC_OPEN
+**
SQLITE_MUTEX_STATIC_PRNG
+**
SQLITE_MUTEX_STATIC_LRU
+**
SQLITE_MUTEX_STATIC_PMEM
+**
SQLITE_MUTEX_STATIC_APP1
+**
SQLITE_MUTEX_STATIC_APP2
+**
SQLITE_MUTEX_STATIC_APP3
+**
SQLITE_MUTEX_STATIC_VFS1
+**
SQLITE_MUTEX_STATIC_VFS2
+**
SQLITE_MUTEX_STATIC_VFS3
+**
+**
+** The first two constants cause sqlite3_mutex_alloc() to create
+** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
+** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
+** The mutex implementation does not need to make a distinction
+** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
+** not want to. But SQLite will only request a recursive mutex in
+** cases where it really needs one. If a faster non-recursive mutex
+** implementation is available on the host platform, the mutex subsystem
+** might return such a mutex in response to SQLITE_MUTEX_FAST.
+**
+** The other allowed parameters to sqlite3_mutex_alloc() each return
+** a pointer to a static preexisting mutex. Six static mutexes are
+** used by the current version of SQLite. Future versions of SQLite
+** may add additional static mutexes. Static mutexes are for internal
+** use by SQLite only. Applications that use SQLite mutexes should
+** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
+** SQLITE_MUTEX_RECURSIVE.
+**
+** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
+** returns a different mutex on every call. But for the static
+** mutex types, the same mutex is returned on every call that has
+** the same type number.
+*/
+static sqlite3_mutex *winMutexAlloc(int iType){
+ sqlite3_mutex *p;
+
+ switch( iType ){
+ case SQLITE_MUTEX_FAST:
+ case SQLITE_MUTEX_RECURSIVE: {
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p ){
+ p->id = iType;
+#ifdef SQLITE_DEBUG
+#ifdef SQLITE_WIN32_MUTEX_TRACE_DYNAMIC
+ p->trace = 1;
+#endif
+#endif
+#if SQLITE_OS_WINRT
+ InitializeCriticalSectionEx(&p->mutex, 0, 0);
+#else
+ InitializeCriticalSection(&p->mutex);
+#endif
+ }
+ break;
+ }
+ default: {
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( iType-2<0 || iType-2>=ArraySize(winMutex_staticMutexes) ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+ p = &winMutex_staticMutexes[iType-2];
+#ifdef SQLITE_DEBUG
+#ifdef SQLITE_WIN32_MUTEX_TRACE_STATIC
+ InterlockedCompareExchange(&p->trace, 1, 0);
+#endif
+#endif
+ break;
+ }
+ }
+ assert( p==0 || p->id==iType );
+ return p;
+}
+
+
+/*
+** This routine deallocates a previously
+** allocated mutex. SQLite is careful to deallocate every
+** mutex that it allocates.
+*/
+static void winMutexFree(sqlite3_mutex *p){
+ assert( p );
+ assert( p->nRef==0 && p->owner==0 );
+ if( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE ){
+ DeleteCriticalSection(&p->mutex);
+ sqlite3_free(p);
+ }else{
+#ifdef SQLITE_ENABLE_API_ARMOR
+ (void)SQLITE_MISUSE_BKPT;
+#endif
+ }
+}
+
+/*
+** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex. If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY. The sqlite3_mutex_try() interface returns SQLITE_OK
+** upon successful entry. Mutexes created using SQLITE_MUTEX_RECURSIVE can
+** be entered multiple times by the same thread. In such cases the,
+** mutex must be exited an equal number of times before another thread
+** can enter. If the same thread tries to enter any other kind of mutex
+** more than once, the behavior is undefined.
+*/
+static void winMutexEnter(sqlite3_mutex *p){
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
+ DWORD tid = GetCurrentThreadId();
+#endif
+#ifdef SQLITE_DEBUG
+ assert( p );
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld2(p, tid) );
+#else
+ assert( p );
+#endif
+ assert( winMutex_isInit==1 );
+ EnterCriticalSection(&p->mutex);
+#ifdef SQLITE_DEBUG
+ assert( p->nRef>0 || p->owner==0 );
+ p->owner = tid;
+ p->nRef++;
+ if( p->trace ){
+ OSTRACE(("ENTER-MUTEX tid=%lu, mutex(%d)=%p (%d), nRef=%d\n",
+ tid, p->id, p, p->trace, p->nRef));
+ }
+#endif
+}
+
+static int winMutexTry(sqlite3_mutex *p){
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
+ DWORD tid = GetCurrentThreadId();
+#endif
+ int rc = SQLITE_BUSY;
+ assert( p );
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld2(p, tid) );
+ /*
+ ** The sqlite3_mutex_try() routine is very rarely used, and when it
+ ** is used it is merely an optimization. So it is OK for it to always
+ ** fail.
+ **
+ ** The TryEnterCriticalSection() interface is only available on WinNT.
+ ** And some windows compilers complain if you try to use it without
+ ** first doing some #defines that prevent SQLite from building on Win98.
+ ** For that reason, we will omit this optimization for now. See
+ ** ticket #2685.
+ */
+#if defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x0400
+ assert( winMutex_isInit==1 );
+ assert( winMutex_isNt>=-1 && winMutex_isNt<=1 );
+ if( winMutex_isNt<0 ){
+ winMutex_isNt = sqlite3_win32_is_nt();
+ }
+ assert( winMutex_isNt==0 || winMutex_isNt==1 );
+ if( winMutex_isNt && TryEnterCriticalSection(&p->mutex) ){
+#ifdef SQLITE_DEBUG
+ p->owner = tid;
+ p->nRef++;
+#endif
+ rc = SQLITE_OK;
+ }
+#else
+ UNUSED_PARAMETER(p);
+#endif
+#ifdef SQLITE_DEBUG
+ if( p->trace ){
+ OSTRACE(("TRY-MUTEX tid=%lu, mutex(%d)=%p (%d), owner=%lu, nRef=%d, rc=%s\n",
+ tid, p->id, p, p->trace, p->owner, p->nRef, sqlite3ErrName(rc)));
+ }
+#endif
+ return rc;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread. The behavior
+** is undefined if the mutex is not currently entered or
+** is not currently allocated. SQLite will never do either.
+*/
+static void winMutexLeave(sqlite3_mutex *p){
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
+ DWORD tid = GetCurrentThreadId();
+#endif
+ assert( p );
+#ifdef SQLITE_DEBUG
+ assert( p->nRef>0 );
+ assert( p->owner==tid );
+ p->nRef--;
+ if( p->nRef==0 ) p->owner = 0;
+ assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
+#endif
+ assert( winMutex_isInit==1 );
+ LeaveCriticalSection(&p->mutex);
+#ifdef SQLITE_DEBUG
+ if( p->trace ){
+ OSTRACE(("LEAVE-MUTEX tid=%lu, mutex(%d)=%p (%d), nRef=%d\n",
+ tid, p->id, p, p->trace, p->nRef));
+ }
+#endif
+}
+
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ winMutexInit,
+ winMutexEnd,
+ winMutexAlloc,
+ winMutexFree,
+ winMutexEnter,
+ winMutexTry,
+ winMutexLeave,
+#ifdef SQLITE_DEBUG
+ winMutexHeld,
+ winMutexNotheld
+#else
+ 0,
+ 0
+#endif
+ };
+ return &sMutex;
+}
+
+#endif /* SQLITE_MUTEX_W32 */
+
+/************** End of mutex_w32.c *******************************************/
+/************** Begin file malloc.c ******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** Memory allocation functions used throughout sqlite.
+*/
+/* #include "sqliteInt.h" */
+/* #include */
+
+/*
+** Attempt to release up to n bytes of non-essential memory currently
+** held by SQLite. An example of non-essential memory is memory used to
+** cache database pages that are not currently in use.
+*/
+SQLITE_API int sqlite3_release_memory(int n){
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+ return sqlite3PcacheReleaseMemory(n);
+#else
+ /* IMPLEMENTATION-OF: R-34391-24921 The sqlite3_release_memory() routine
+ ** is a no-op returning zero if SQLite is not compiled with
+ ** SQLITE_ENABLE_MEMORY_MANAGEMENT. */
+ UNUSED_PARAMETER(n);
+ return 0;
+#endif
+}
+
+/*
+** State information local to the memory allocation subsystem.
+*/
+static SQLITE_WSD struct Mem0Global {
+ sqlite3_mutex *mutex; /* Mutex to serialize access */
+ sqlite3_int64 alarmThreshold; /* The soft heap limit */
+
+ /*
+ ** True if heap is nearly "full" where "full" is defined by the
+ ** sqlite3_soft_heap_limit() setting.
+ */
+ int nearlyFull;
+} mem0 = { 0, 0, 0 };
+
+#define mem0 GLOBAL(struct Mem0Global, mem0)
+
+/*
+** Return the memory allocator mutex. sqlite3_status() needs it.
+*/
+SQLITE_PRIVATE sqlite3_mutex *sqlite3MallocMutex(void){
+ return mem0.mutex;
+}
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Deprecated external interface. It used to set an alarm callback
+** that was invoked when memory usage grew too large. Now it is a
+** no-op.
+*/
+SQLITE_API int sqlite3_memory_alarm(
+ void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+ void *pArg,
+ sqlite3_int64 iThreshold
+){
+ (void)xCallback;
+ (void)pArg;
+ (void)iThreshold;
+ return SQLITE_OK;
+}
+#endif
+
+/*
+** Set the soft heap-size limit for the library. Passing a zero or
+** negative value indicates no limit.
+*/
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){
+ sqlite3_int64 priorLimit;
+ sqlite3_int64 excess;
+ sqlite3_int64 nUsed;
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return -1;
+#endif
+ sqlite3_mutex_enter(mem0.mutex);
+ priorLimit = mem0.alarmThreshold;
+ if( n<0 ){
+ sqlite3_mutex_leave(mem0.mutex);
+ return priorLimit;
+ }
+ mem0.alarmThreshold = n;
+ nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+ mem0.nearlyFull = (n>0 && n<=nUsed);
+ sqlite3_mutex_leave(mem0.mutex);
+ excess = sqlite3_memory_used() - n;
+ if( excess>0 ) sqlite3_release_memory((int)(excess & 0x7fffffff));
+ return priorLimit;
+}
+SQLITE_API void sqlite3_soft_heap_limit(int n){
+ if( n<0 ) n = 0;
+ sqlite3_soft_heap_limit64(n);
+}
+
+/*
+** Initialize the memory allocation subsystem.
+*/
+SQLITE_PRIVATE int sqlite3MallocInit(void){
+ int rc;
+ if( sqlite3GlobalConfig.m.xMalloc==0 ){
+ sqlite3MemSetDefault();
+ }
+ memset(&mem0, 0, sizeof(mem0));
+ mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+ if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
+ || sqlite3GlobalConfig.nPage<=0 ){
+ sqlite3GlobalConfig.pPage = 0;
+ sqlite3GlobalConfig.szPage = 0;
+ }
+ rc = sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
+ if( rc!=SQLITE_OK ) memset(&mem0, 0, sizeof(mem0));
+ return rc;
+}
+
+/*
+** Return true if the heap is currently under memory pressure - in other
+** words if the amount of heap used is close to the limit set by
+** sqlite3_soft_heap_limit().
+*/
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void){
+ return mem0.nearlyFull;
+}
+
+/*
+** Deinitialize the memory allocation subsystem.
+*/
+SQLITE_PRIVATE void sqlite3MallocEnd(void){
+ if( sqlite3GlobalConfig.m.xShutdown ){
+ sqlite3GlobalConfig.m.xShutdown(sqlite3GlobalConfig.m.pAppData);
+ }
+ memset(&mem0, 0, sizeof(mem0));
+}
+
+/*
+** Return the amount of memory currently checked out.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
+ sqlite3_int64 res, mx;
+ sqlite3_status64(SQLITE_STATUS_MEMORY_USED, &res, &mx, 0);
+ return res;
+}
+
+/*
+** Return the maximum amount of memory that has ever been
+** checked out since either the beginning of this process
+** or since the most recent reset.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
+ sqlite3_int64 res, mx;
+ sqlite3_status64(SQLITE_STATUS_MEMORY_USED, &res, &mx, resetFlag);
+ return mx;
+}
+
+/*
+** Trigger the alarm
+*/
+static void sqlite3MallocAlarm(int nByte){
+ if( mem0.alarmThreshold<=0 ) return;
+ sqlite3_mutex_leave(mem0.mutex);
+ sqlite3_release_memory(nByte);
+ sqlite3_mutex_enter(mem0.mutex);
+}
+
+/*
+** Do a memory allocation with statistics and alarms. Assume the
+** lock is already held.
+*/
+static void mallocWithAlarm(int n, void **pp){
+ void *p;
+ int nFull;
+ assert( sqlite3_mutex_held(mem0.mutex) );
+ assert( n>0 );
+
+ /* In Firefox (circa 2017-02-08), xRoundup() is remapped to an internal
+ ** implementation of malloc_good_size(), which must be called in debug
+ ** mode and specifically when the DMD "Dark Matter Detector" is enabled
+ ** or else a crash results. Hence, do not attempt to optimize out the
+ ** following xRoundup() call. */
+ nFull = sqlite3GlobalConfig.m.xRoundup(n);
+
+#ifdef SQLITE_MAX_MEMORY
+ if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED)+nFull>SQLITE_MAX_MEMORY ){
+ *pp = 0;
+ return;
+ }
+#endif
+
+ sqlite3StatusHighwater(SQLITE_STATUS_MALLOC_SIZE, n);
+ if( mem0.alarmThreshold>0 ){
+ sqlite3_int64 nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+ if( nUsed >= mem0.alarmThreshold - nFull ){
+ mem0.nearlyFull = 1;
+ sqlite3MallocAlarm(nFull);
+ }else{
+ mem0.nearlyFull = 0;
+ }
+ }
+ p = sqlite3GlobalConfig.m.xMalloc(nFull);
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+ if( p==0 && mem0.alarmThreshold>0 ){
+ sqlite3MallocAlarm(nFull);
+ p = sqlite3GlobalConfig.m.xMalloc(nFull);
+ }
+#endif
+ if( p ){
+ nFull = sqlite3MallocSize(p);
+ sqlite3StatusUp(SQLITE_STATUS_MEMORY_USED, nFull);
+ sqlite3StatusUp(SQLITE_STATUS_MALLOC_COUNT, 1);
+ }
+ *pp = p;
+}
+
+/*
+** Allocate memory. This routine is like sqlite3_malloc() except that it
+** assumes the memory subsystem has already been initialized.
+*/
+SQLITE_PRIVATE void *sqlite3Malloc(u64 n){
+ void *p;
+ if( n==0 || n>=0x7fffff00 ){
+ /* A memory allocation of a number of bytes which is near the maximum
+ ** signed integer value might cause an integer overflow inside of the
+ ** xMalloc(). Hence we limit the maximum size to 0x7fffff00, giving
+ ** 255 bytes of overhead. SQLite itself will never use anything near
+ ** this amount. The only way to reach the limit is with sqlite3_malloc() */
+ p = 0;
+ }else if( sqlite3GlobalConfig.bMemstat ){
+ sqlite3_mutex_enter(mem0.mutex);
+ mallocWithAlarm((int)n, &p);
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ p = sqlite3GlobalConfig.m.xMalloc((int)n);
+ }
+ assert( EIGHT_BYTE_ALIGNMENT(p) ); /* IMP: R-11148-40995 */
+ return p;
+}
+
+/*
+** This version of the memory allocation is for use by the application.
+** First make sure the memory subsystem is initialized, then do the
+** allocation.
+*/
+SQLITE_API void *sqlite3_malloc(int n){
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return n<=0 ? 0 : sqlite3Malloc(n);
+}
+SQLITE_API void *sqlite3_malloc64(sqlite3_uint64 n){
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return sqlite3Malloc(n);
+}
+
+/*
+** TRUE if p is a lookaside memory allocation from db
+*/
+#ifndef SQLITE_OMIT_LOOKASIDE
+static int isLookaside(sqlite3 *db, void *p){
+ return SQLITE_WITHIN(p, db->lookaside.pStart, db->lookaside.pEnd);
+}
+#else
+#define isLookaside(A,B) 0
+#endif
+
+/*
+** Return the size of a memory allocation previously obtained from
+** sqlite3Malloc() or sqlite3_malloc().
+*/
+SQLITE_PRIVATE int sqlite3MallocSize(void *p){
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+ return sqlite3GlobalConfig.m.xSize(p);
+}
+SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, void *p){
+ assert( p!=0 );
+ if( db==0 || !isLookaside(db,p) ){
+#ifdef SQLITE_DEBUG
+ if( db==0 ){
+ assert( sqlite3MemdebugNoType(p, (u8)~MEMTYPE_HEAP) );
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+ }else{
+ assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
+ assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
+ }
+#endif
+ return sqlite3GlobalConfig.m.xSize(p);
+ }else{
+ assert( sqlite3_mutex_held(db->mutex) );
+ return db->lookaside.sz;
+ }
+}
+SQLITE_API sqlite3_uint64 sqlite3_msize(void *p){
+ assert( sqlite3MemdebugNoType(p, (u8)~MEMTYPE_HEAP) );
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+ return p ? sqlite3GlobalConfig.m.xSize(p) : 0;
+}
+
+/*
+** Free memory previously obtained from sqlite3Malloc().
+*/
+SQLITE_API void sqlite3_free(void *p){
+ if( p==0 ) return; /* IMP: R-49053-54554 */
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+ assert( sqlite3MemdebugNoType(p, (u8)~MEMTYPE_HEAP) );
+ if( sqlite3GlobalConfig.bMemstat ){
+ sqlite3_mutex_enter(mem0.mutex);
+ sqlite3StatusDown(SQLITE_STATUS_MEMORY_USED, sqlite3MallocSize(p));
+ sqlite3StatusDown(SQLITE_STATUS_MALLOC_COUNT, 1);
+ sqlite3GlobalConfig.m.xFree(p);
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ sqlite3GlobalConfig.m.xFree(p);
+ }
+}
+
+/*
+** Add the size of memory allocation "p" to the count in
+** *db->pnBytesFreed.
+*/
+static SQLITE_NOINLINE void measureAllocationSize(sqlite3 *db, void *p){
+ *db->pnBytesFreed += sqlite3DbMallocSize(db,p);
+}
+
+/*
+** Free memory that might be associated with a particular database
+** connection. Calling sqlite3DbFree(D,X) for X==0 is a harmless no-op.
+** The sqlite3DbFreeNN(D,X) version requires that X be non-NULL.
+*/
+SQLITE_PRIVATE void sqlite3DbFreeNN(sqlite3 *db, void *p){
+ assert( db==0 || sqlite3_mutex_held(db->mutex) );
+ assert( p!=0 );
+ if( db ){
+ if( db->pnBytesFreed ){
+ measureAllocationSize(db, p);
+ return;
+ }
+ if( isLookaside(db, p) ){
+ LookasideSlot *pBuf = (LookasideSlot*)p;
+#ifdef SQLITE_DEBUG
+ /* Trash all content in the buffer being freed */
+ memset(p, 0xaa, db->lookaside.sz);
+#endif
+ pBuf->pNext = db->lookaside.pFree;
+ db->lookaside.pFree = pBuf;
+ return;
+ }
+ }
+ assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
+ assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
+ assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
+ sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+ sqlite3_free(p);
+}
+SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
+ assert( db==0 || sqlite3_mutex_held(db->mutex) );
+ if( p ) sqlite3DbFreeNN(db, p);
+}
+
+/*
+** Change the size of an existing memory allocation
+*/
+SQLITE_PRIVATE void *sqlite3Realloc(void *pOld, u64 nBytes){
+ int nOld, nNew, nDiff;
+ void *pNew;
+ assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
+ assert( sqlite3MemdebugNoType(pOld, (u8)~MEMTYPE_HEAP) );
+ if( pOld==0 ){
+ return sqlite3Malloc(nBytes); /* IMP: R-04300-56712 */
+ }
+ if( nBytes==0 ){
+ sqlite3_free(pOld); /* IMP: R-26507-47431 */
+ return 0;
+ }
+ if( nBytes>=0x7fffff00 ){
+ /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
+ return 0;
+ }
+ nOld = sqlite3MallocSize(pOld);
+ /* IMPLEMENTATION-OF: R-46199-30249 SQLite guarantees that the second
+ ** argument to xRealloc is always a value returned by a prior call to
+ ** xRoundup. */
+ nNew = sqlite3GlobalConfig.m.xRoundup((int)nBytes);
+ if( nOld==nNew ){
+ pNew = pOld;
+ }else if( sqlite3GlobalConfig.bMemstat ){
+ sqlite3_mutex_enter(mem0.mutex);
+ sqlite3StatusHighwater(SQLITE_STATUS_MALLOC_SIZE, (int)nBytes);
+ nDiff = nNew - nOld;
+ if( nDiff>0 && sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >=
+ mem0.alarmThreshold-nDiff ){
+ sqlite3MallocAlarm(nDiff);
+ }
+ pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+ if( pNew==0 && mem0.alarmThreshold>0 ){
+ sqlite3MallocAlarm((int)nBytes);
+ pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+ }
+ if( pNew ){
+ nNew = sqlite3MallocSize(pNew);
+ sqlite3StatusUp(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
+ }
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+ }
+ assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-11148-40995 */
+ return pNew;
+}
+
+/*
+** The public interface to sqlite3Realloc. Make sure that the memory
+** subsystem is initialized prior to invoking sqliteRealloc.
+*/
+SQLITE_API void *sqlite3_realloc(void *pOld, int n){
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ if( n<0 ) n = 0; /* IMP: R-26507-47431 */
+ return sqlite3Realloc(pOld, n);
+}
+SQLITE_API void *sqlite3_realloc64(void *pOld, sqlite3_uint64 n){
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return sqlite3Realloc(pOld, n);
+}
+
+
+/*
+** Allocate and zero memory.
+*/
+SQLITE_PRIVATE void *sqlite3MallocZero(u64 n){
+ void *p = sqlite3Malloc(n);
+ if( p ){
+ memset(p, 0, (size_t)n);
+ }
+ return p;
+}
+
+/*
+** Allocate and zero memory. If the allocation fails, make
+** the mallocFailed flag in the connection pointer.
+*/
+SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3 *db, u64 n){
+ void *p;
+ testcase( db==0 );
+ p = sqlite3DbMallocRaw(db, n);
+ if( p ) memset(p, 0, (size_t)n);
+ return p;
+}
+
+
+/* Finish the work of sqlite3DbMallocRawNN for the unusual and
+** slower case when the allocation cannot be fulfilled using lookaside.
+*/
+static SQLITE_NOINLINE void *dbMallocRawFinish(sqlite3 *db, u64 n){
+ void *p;
+ assert( db!=0 );
+ p = sqlite3Malloc(n);
+ if( !p ) sqlite3OomFault(db);
+ sqlite3MemdebugSetType(p,
+ (db->lookaside.bDisable==0) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP);
+ return p;
+}
+
+/*
+** Allocate memory, either lookaside (if possible) or heap.
+** If the allocation fails, set the mallocFailed flag in
+** the connection pointer.
+**
+** If db!=0 and db->mallocFailed is true (indicating a prior malloc
+** failure on the same database connection) then always return 0.
+** Hence for a particular database connection, once malloc starts
+** failing, it fails consistently until mallocFailed is reset.
+** This is an important assumption. There are many places in the
+** code that do things like this:
+**
+** int *a = (int*)sqlite3DbMallocRaw(db, 100);
+** int *b = (int*)sqlite3DbMallocRaw(db, 200);
+** if( b ) a[10] = 9;
+**
+** In other words, if a subsequent malloc (ex: "b") worked, it is assumed
+** that all prior mallocs (ex: "a") worked too.
+**
+** The sqlite3MallocRawNN() variant guarantees that the "db" parameter is
+** not a NULL pointer.
+*/
+SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, u64 n){
+ void *p;
+ if( db ) return sqlite3DbMallocRawNN(db, n);
+ p = sqlite3Malloc(n);
+ sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+ return p;
+}
+SQLITE_PRIVATE void *sqlite3DbMallocRawNN(sqlite3 *db, u64 n){
+#ifndef SQLITE_OMIT_LOOKASIDE
+ LookasideSlot *pBuf;
+ assert( db!=0 );
+ assert( sqlite3_mutex_held(db->mutex) );
+ assert( db->pnBytesFreed==0 );
+ if( db->lookaside.bDisable==0 ){
+ assert( db->mallocFailed==0 );
+ if( n>db->lookaside.sz ){
+ db->lookaside.anStat[1]++;
+ }else if( (pBuf = db->lookaside.pFree)!=0 ){
+ db->lookaside.pFree = pBuf->pNext;
+ db->lookaside.anStat[0]++;
+ return (void*)pBuf;
+ }else if( (pBuf = db->lookaside.pInit)!=0 ){
+ db->lookaside.pInit = pBuf->pNext;
+ db->lookaside.anStat[0]++;
+ return (void*)pBuf;
+ }else{
+ db->lookaside.anStat[2]++;
+ }
+ }else if( db->mallocFailed ){
+ return 0;
+ }
+#else
+ assert( db!=0 );
+ assert( sqlite3_mutex_held(db->mutex) );
+ assert( db->pnBytesFreed==0 );
+ if( db->mallocFailed ){
+ return 0;
+ }
+#endif
+ return dbMallocRawFinish(db, n);
+}
+
+/* Forward declaration */
+static SQLITE_NOINLINE void *dbReallocFinish(sqlite3 *db, void *p, u64 n);
+
+/*
+** Resize the block of memory pointed to by p to n bytes. If the
+** resize fails, set the mallocFailed flag in the connection object.
+*/
+SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *db, void *p, u64 n){
+ assert( db!=0 );
+ if( p==0 ) return sqlite3DbMallocRawNN(db, n);
+ assert( sqlite3_mutex_held(db->mutex) );
+ if( isLookaside(db,p) && n<=db->lookaside.sz ) return p;
+ return dbReallocFinish(db, p, n);
+}
+static SQLITE_NOINLINE void *dbReallocFinish(sqlite3 *db, void *p, u64 n){
+ void *pNew = 0;
+ assert( db!=0 );
+ assert( p!=0 );
+ if( db->mallocFailed==0 ){
+ if( isLookaside(db, p) ){
+ pNew = sqlite3DbMallocRawNN(db, n);
+ if( pNew ){
+ memcpy(pNew, p, db->lookaside.sz);
+ sqlite3DbFree(db, p);
+ }
+ }else{
+ assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
+ assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
+ sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+ pNew = sqlite3_realloc64(p, n);
+ if( !pNew ){
+ sqlite3OomFault(db);
+ }
+ sqlite3MemdebugSetType(pNew,
+ (db->lookaside.bDisable==0 ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
+ }
+ }
+ return pNew;
+}
+
+/*
+** Attempt to reallocate p. If the reallocation fails, then free p
+** and set the mallocFailed flag in the database connection.
+*/
+SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, u64 n){
+ void *pNew;
+ pNew = sqlite3DbRealloc(db, p, n);
+ if( !pNew ){
+ sqlite3DbFree(db, p);
+ }
+ return pNew;
+}
+
+/*
+** Make a copy of a string in memory obtained from sqliteMalloc(). These
+** functions call sqlite3MallocRaw() directly instead of sqliteMalloc(). This
+** is because when memory debugging is turned on, these two functions are
+** called via macros that record the current file and line number in the
+** ThreadData structure.
+*/
+SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3 *db, const char *z){
+ char *zNew;
+ size_t n;
+ if( z==0 ){
+ return 0;
+ }
+ n = strlen(z) + 1;
+ zNew = sqlite3DbMallocRaw(db, n);
+ if( zNew ){
+ memcpy(zNew, z, n);
+ }
+ return zNew;
+}
+SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3 *db, const char *z, u64 n){
+ char *zNew;
+ assert( db!=0 );
+ if( z==0 ){
+ return 0;
+ }
+ assert( (n&0x7fffffff)==n );
+ zNew = sqlite3DbMallocRawNN(db, n+1);
+ if( zNew ){
+ memcpy(zNew, z, (size_t)n);
+ zNew[n] = 0;
+ }
+ return zNew;
+}
+
+/*
+** The text between zStart and zEnd represents a phrase within a larger
+** SQL statement. Make a copy of this phrase in space obtained form
+** sqlite3DbMalloc(). Omit leading and trailing whitespace.
+*/
+SQLITE_PRIVATE char *sqlite3DbSpanDup(sqlite3 *db, const char *zStart, const char *zEnd){
+ int n;
+ while( sqlite3Isspace(zStart[0]) ) zStart++;
+ n = (int)(zEnd - zStart);
+ while( ALWAYS(n>0) && sqlite3Isspace(zStart[n-1]) ) n--;
+ return sqlite3DbStrNDup(db, zStart, n);
+}
+
+/*
+** Free any prior content in *pz and replace it with a copy of zNew.
+*/
+SQLITE_PRIVATE void sqlite3SetString(char **pz, sqlite3 *db, const char *zNew){
+ sqlite3DbFree(db, *pz);
+ *pz = sqlite3DbStrDup(db, zNew);
+}
+
+/*
+** Call this routine to record the fact that an OOM (out-of-memory) error
+** has happened. This routine will set db->mallocFailed, and also
+** temporarily disable the lookaside memory allocator and interrupt
+** any running VDBEs.
+*/
+SQLITE_PRIVATE void sqlite3OomFault(sqlite3 *db){
+ if( db->mallocFailed==0 && db->bBenignMalloc==0 ){
+ db->mallocFailed = 1;
+ if( db->nVdbeExec>0 ){
+ db->u1.isInterrupted = 1;
+ }
+ db->lookaside.bDisable++;
+ }
+}
+
+/*
+** This routine reactivates the memory allocator and clears the
+** db->mallocFailed flag as necessary.
+**
+** The memory allocator is not restarted if there are running
+** VDBEs.
+*/
+SQLITE_PRIVATE void sqlite3OomClear(sqlite3 *db){
+ if( db->mallocFailed && db->nVdbeExec==0 ){
+ db->mallocFailed = 0;
+ db->u1.isInterrupted = 0;
+ assert( db->lookaside.bDisable>0 );
+ db->lookaside.bDisable--;
+ }
+}
+
+/*
+** Take actions at the end of an API call to indicate an OOM error
+*/
+static SQLITE_NOINLINE int apiOomError(sqlite3 *db){
+ sqlite3OomClear(db);
+ sqlite3Error(db, SQLITE_NOMEM);
+ return SQLITE_NOMEM_BKPT;
+}
+
+/*
+** This function must be called before exiting any API function (i.e.
+** returning control to the user) that has called sqlite3_malloc or
+** sqlite3_realloc.
+**
+** The returned value is normally a copy of the second argument to this
+** function. However, if a malloc() failure has occurred since the previous
+** invocation SQLITE_NOMEM is returned instead.
+**
+** If an OOM as occurred, then the connection error-code (the value
+** returned by sqlite3_errcode()) is set to SQLITE_NOMEM.
+*/
+SQLITE_PRIVATE int sqlite3ApiExit(sqlite3* db, int rc){
+ /* If the db handle must hold the connection handle mutex here.
+ ** Otherwise the read (and possible write) of db->mallocFailed
+ ** is unsafe, as is the call to sqlite3Error().
+ */
+ assert( db!=0 );
+ assert( sqlite3_mutex_held(db->mutex) );
+ if( db->mallocFailed || rc==SQLITE_IOERR_NOMEM ){
+ return apiOomError(db);
+ }
+ return rc & db->errMask;
+}
+
+/************** End of malloc.c **********************************************/
+/************** Begin file printf.c ******************************************/
+/*
+** The "printf" code that follows dates from the 1980's. It is in
+** the public domain.
+**
+**************************************************************************
+**
+** This file contains code for a set of "printf"-like routines. These
+** routines format strings much like the printf() from the standard C
+** library, though the implementation here has enhancements to support
+** SQLite.
+*/
+/* #include "sqliteInt.h" */
+
+/*
+** Conversion types fall into various categories as defined by the
+** following enumeration.
+*/
+#define etRADIX 0 /* non-decimal integer types. %x %o */
+#define etFLOAT 1 /* Floating point. %f */
+#define etEXP 2 /* Exponentional notation. %e and %E */
+#define etGENERIC 3 /* Floating or exponential, depending on exponent. %g */
+#define etSIZE 4 /* Return number of characters processed so far. %n */
+#define etSTRING 5 /* Strings. %s */
+#define etDYNSTRING 6 /* Dynamically allocated strings. %z */
+#define etPERCENT 7 /* Percent symbol. %% */
+#define etCHARX 8 /* Characters. %c */
+/* The rest are extensions, not normally found in printf() */
+#define etSQLESCAPE 9 /* Strings with '\'' doubled. %q */
+#define etSQLESCAPE2 10 /* Strings with '\'' doubled and enclosed in '',
+ NULL pointers replaced by SQL NULL. %Q */
+#define etTOKEN 11 /* a pointer to a Token structure */
+#define etSRCLIST 12 /* a pointer to a SrcList */
+#define etPOINTER 13 /* The %p conversion */
+#define etSQLESCAPE3 14 /* %w -> Strings with '\"' doubled */
+#define etORDINAL 15 /* %r -> 1st, 2nd, 3rd, 4th, etc. English only */
+#define etDECIMAL 16 /* %d or %u, but not %x, %o */
+
+#define etINVALID 17 /* Any unrecognized conversion type */
+
+
+/*
+** An "etByte" is an 8-bit unsigned value.
+*/
+typedef unsigned char etByte;
+
+/*
+** Each builtin conversion character (ex: the 'd' in "%d") is described
+** by an instance of the following structure
+*/
+typedef struct et_info { /* Information about each format field */
+ char fmttype; /* The format field code letter */
+ etByte base; /* The base for radix conversion */
+ etByte flags; /* One or more of FLAG_ constants below */
+ etByte type; /* Conversion paradigm */
+ etByte charset; /* Offset into aDigits[] of the digits string */
+ etByte prefix; /* Offset into aPrefix[] of the prefix string */
+} et_info;
+
+/*
+** Allowed values for et_info.flags
+*/
+#define FLAG_SIGNED 1 /* True if the value to convert is signed */
+#define FLAG_STRING 4 /* Allow infinite precision */
+
+
+/*
+** The following table is searched linearly, so it is good to put the
+** most frequently used conversion types first.
+*/
+static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
+static const char aPrefix[] = "-x0\000X0";
+static const et_info fmtinfo[] = {
+ { 'd', 10, 1, etDECIMAL, 0, 0 },
+ { 's', 0, 4, etSTRING, 0, 0 },
+ { 'g', 0, 1, etGENERIC, 30, 0 },
+ { 'z', 0, 4, etDYNSTRING, 0, 0 },
+ { 'q', 0, 4, etSQLESCAPE, 0, 0 },
+ { 'Q', 0, 4, etSQLESCAPE2, 0, 0 },
+ { 'w', 0, 4, etSQLESCAPE3, 0, 0 },
+ { 'c', 0, 0, etCHARX, 0, 0 },
+ { 'o', 8, 0, etRADIX, 0, 2 },
+ { 'u', 10, 0, etDECIMAL, 0, 0 },
+ { 'x', 16, 0, etRADIX, 16, 1 },
+ { 'X', 16, 0, etRADIX, 0, 4 },
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ { 'f', 0, 1, etFLOAT, 0, 0 },
+ { 'e', 0, 1, etEXP, 30, 0 },
+ { 'E', 0, 1, etEXP, 14, 0 },
+ { 'G', 0, 1, etGENERIC, 14, 0 },
+#endif
+ { 'i', 10, 1, etDECIMAL, 0, 0 },
+ { 'n', 0, 0, etSIZE, 0, 0 },
+ { '%', 0, 0, etPERCENT, 0, 0 },
+ { 'p', 16, 0, etPOINTER, 0, 1 },
+
+ /* All the rest are undocumented and are for internal use only */
+ { 'T', 0, 0, etTOKEN, 0, 0 },
+ { 'S', 0, 0, etSRCLIST, 0, 0 },
+ { 'r', 10, 1, etORDINAL, 0, 0 },
+};
+
+/*
+** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
+** conversions will work.
+*/
+#ifndef SQLITE_OMIT_FLOATING_POINT
+/*
+** "*val" is a double such that 0.1 <= *val < 10.0
+** Return the ascii code for the leading digit of *val, then
+** multiply "*val" by 10.0 to renormalize.
+**
+** Example:
+** input: *val = 3.14159
+** output: *val = 1.4159 function return = '3'
+**
+** The counter *cnt is incremented each time. After counter exceeds
+** 16 (the number of significant digits in a 64-bit float) '0' is
+** always returned.
+*/
+static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
+ int digit;
+ LONGDOUBLE_TYPE d;
+ if( (*cnt)<=0 ) return '0';
+ (*cnt)--;
+ digit = (int)*val;
+ d = digit;
+ digit += '0';
+ *val = (*val - d)*10.0;
+ return (char)digit;
+}
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+
+/*
+** Set the StrAccum object to an error mode.
+*/
+static void setStrAccumError(StrAccum *p, u8 eError){
+ assert( eError==SQLITE_NOMEM || eError==SQLITE_TOOBIG );
+ p->accError = eError;
+ p->nAlloc = 0;
+}
+
+/*
+** Extra argument values from a PrintfArguments object
+*/
+static sqlite3_int64 getIntArg(PrintfArguments *p){
+ if( p->nArg<=p->nUsed ) return 0;
+ return sqlite3_value_int64(p->apArg[p->nUsed++]);
+}
+static double getDoubleArg(PrintfArguments *p){
+ if( p->nArg<=p->nUsed ) return 0.0;
+ return sqlite3_value_double(p->apArg[p->nUsed++]);
+}
+static char *getTextArg(PrintfArguments *p){
+ if( p->nArg<=p->nUsed ) return 0;
+ return (char*)sqlite3_value_text(p->apArg[p->nUsed++]);
+}
+
+
+/*
+** On machines with a small stack size, you can redefine the
+** SQLITE_PRINT_BUF_SIZE to be something smaller, if desired.
+*/
+#ifndef SQLITE_PRINT_BUF_SIZE
+# define SQLITE_PRINT_BUF_SIZE 70
+#endif
+#define etBUFSIZE SQLITE_PRINT_BUF_SIZE /* Size of the output buffer */
+
+/*
+** Render a string given by "fmt" into the StrAccum object.
+*/
+SQLITE_API void sqlite3_str_vappendf(
+ sqlite3_str *pAccum, /* Accumulate results here */
+ const char *fmt, /* Format string */
+ va_list ap /* arguments */
+){
+ int c; /* Next character in the format string */
+ char *bufpt; /* Pointer to the conversion buffer */
+ int precision; /* Precision of the current field */
+ int length; /* Length of the field */
+ int idx; /* A general purpose loop counter */
+ int width; /* Width of the current field */
+ etByte flag_leftjustify; /* True if "-" flag is present */
+ etByte flag_prefix; /* '+' or ' ' or 0 for prefix */
+ etByte flag_alternateform; /* True if "#" flag is present */
+ etByte flag_altform2; /* True if "!" flag is present */
+ etByte flag_zeropad; /* True if field width constant starts with zero */
+ etByte flag_long; /* 1 for the "l" flag, 2 for "ll", 0 by default */
+ etByte done; /* Loop termination flag */
+ etByte cThousand; /* Thousands separator for %d and %u */
+ etByte xtype = etINVALID; /* Conversion paradigm */
+ u8 bArgList; /* True for SQLITE_PRINTF_SQLFUNC */
+ char prefix; /* Prefix character. "+" or "-" or " " or '\0'. */
+ sqlite_uint64 longvalue; /* Value for integer types */
+ LONGDOUBLE_TYPE realvalue; /* Value for real types */
+ const et_info *infop; /* Pointer to the appropriate info structure */
+ char *zOut; /* Rendering buffer */
+ int nOut; /* Size of the rendering buffer */
+ char *zExtra = 0; /* Malloced memory used by some conversion */
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ int exp, e2; /* exponent of real numbers */
+ int nsd; /* Number of significant digits returned */
+ double rounder; /* Used for rounding floating point values */
+ etByte flag_dp; /* True if decimal point should be shown */
+ etByte flag_rtz; /* True if trailing zeros should be removed */
+#endif
+ PrintfArguments *pArgList = 0; /* Arguments for SQLITE_PRINTF_SQLFUNC */
+ char buf[etBUFSIZE]; /* Conversion buffer */
+
+ /* pAccum never starts out with an empty buffer that was obtained from
+ ** malloc(). This precondition is required by the mprintf("%z...")
+ ** optimization. */
+ assert( pAccum->nChar>0 || (pAccum->printfFlags&SQLITE_PRINTF_MALLOCED)==0 );
+
+ bufpt = 0;
+ if( (pAccum->printfFlags & SQLITE_PRINTF_SQLFUNC)!=0 ){
+ pArgList = va_arg(ap, PrintfArguments*);
+ bArgList = 1;
+ }else{
+ bArgList = 0;
+ }
+ for(; (c=(*fmt))!=0; ++fmt){
+ if( c!='%' ){
+ bufpt = (char *)fmt;
+#if HAVE_STRCHRNUL
+ fmt = strchrnul(fmt, '%');
+#else
+ do{ fmt++; }while( *fmt && *fmt != '%' );
+#endif
+ sqlite3_str_append(pAccum, bufpt, (int)(fmt - bufpt));
+ if( *fmt==0 ) break;
+ }
+ if( (c=(*++fmt))==0 ){
+ sqlite3_str_append(pAccum, "%", 1);
+ break;
+ }
+ /* Find out what flags are present */
+ flag_leftjustify = flag_prefix = cThousand =
+ flag_alternateform = flag_altform2 = flag_zeropad = 0;
+ done = 0;
+ do{
+ switch( c ){
+ case '-': flag_leftjustify = 1; break;
+ case '+': flag_prefix = '+'; break;
+ case ' ': flag_prefix = ' '; break;
+ case '#': flag_alternateform = 1; break;
+ case '!': flag_altform2 = 1; break;
+ case '0': flag_zeropad = 1; break;
+ case ',': cThousand = ','; break;
+ default: done = 1; break;
+ }
+ }while( !done && (c=(*++fmt))!=0 );
+ /* Get the field width */
+ if( c=='*' ){
+ if( bArgList ){
+ width = (int)getIntArg(pArgList);
+ }else{
+ width = va_arg(ap,int);
+ }
+ if( width<0 ){
+ flag_leftjustify = 1;
+ width = width >= -2147483647 ? -width : 0;
+ }
+ c = *++fmt;
+ }else{
+ unsigned wx = 0;
+ while( c>='0' && c<='9' ){
+ wx = wx*10 + c - '0';
+ c = *++fmt;
+ }
+ testcase( wx>0x7fffffff );
+ width = wx & 0x7fffffff;
+ }
+ assert( width>=0 );
+#ifdef SQLITE_PRINTF_PRECISION_LIMIT
+ if( width>SQLITE_PRINTF_PRECISION_LIMIT ){
+ width = SQLITE_PRINTF_PRECISION_LIMIT;
+ }
+#endif
+
+ /* Get the precision */
+ if( c=='.' ){
+ c = *++fmt;
+ if( c=='*' ){
+ if( bArgList ){
+ precision = (int)getIntArg(pArgList);
+ }else{
+ precision = va_arg(ap,int);
+ }
+ c = *++fmt;
+ if( precision<0 ){
+ precision = precision >= -2147483647 ? -precision : -1;
+ }
+ }else{
+ unsigned px = 0;
+ while( c>='0' && c<='9' ){
+ px = px*10 + c - '0';
+ c = *++fmt;
+ }
+ testcase( px>0x7fffffff );
+ precision = px & 0x7fffffff;
+ }
+ }else{
+ precision = -1;
+ }
+ assert( precision>=(-1) );
+#ifdef SQLITE_PRINTF_PRECISION_LIMIT
+ if( precision>SQLITE_PRINTF_PRECISION_LIMIT ){
+ precision = SQLITE_PRINTF_PRECISION_LIMIT;
+ }
+#endif
+
+
+ /* Get the conversion type modifier */
+ if( c=='l' ){
+ flag_long = 1;
+ c = *++fmt;
+ if( c=='l' ){
+ flag_long = 2;
+ c = *++fmt;
+ }
+ }else{
+ flag_long = 0;
+ }
+ /* Fetch the info entry for the field */
+ infop = &fmtinfo[0];
+ xtype = etINVALID;
+ for(idx=0; idxtype;
+ break;
+ }
+ }
+
+ /*
+ ** At this point, variables are initialized as follows:
+ **
+ ** flag_alternateform TRUE if a '#' is present.
+ ** flag_altform2 TRUE if a '!' is present.
+ ** flag_prefix '+' or ' ' or zero
+ ** flag_leftjustify TRUE if a '-' is present or if the
+ ** field width was negative.
+ ** flag_zeropad TRUE if the width began with 0.
+ ** flag_long 1 for "l", 2 for "ll"
+ ** width The specified field width. This is
+ ** always non-negative. Zero is the default.
+ ** precision The specified precision. The default
+ ** is -1.
+ ** xtype The class of the conversion.
+ ** infop Pointer to the appropriate info struct.
+ */
+ switch( xtype ){
+ case etPOINTER:
+ flag_long = sizeof(char*)==sizeof(i64) ? 2 :
+ sizeof(char*)==sizeof(long int) ? 1 : 0;
+ /* Fall through into the next case */
+ case etORDINAL:
+ case etRADIX:
+ cThousand = 0;
+ /* Fall through into the next case */
+ case etDECIMAL:
+ if( infop->flags & FLAG_SIGNED ){
+ i64 v;
+ if( bArgList ){
+ v = getIntArg(pArgList);
+ }else if( flag_long ){
+ if( flag_long==2 ){
+ v = va_arg(ap,i64) ;
+ }else{
+ v = va_arg(ap,long int);
+ }
+ }else{
+ v = va_arg(ap,int);
+ }
+ if( v<0 ){
+ if( v==SMALLEST_INT64 ){
+ longvalue = ((u64)1)<<63;
+ }else{
+ longvalue = -v;
+ }
+ prefix = '-';
+ }else{
+ longvalue = v;
+ prefix = flag_prefix;
+ }
+ }else{
+ if( bArgList ){
+ longvalue = (u64)getIntArg(pArgList);
+ }else if( flag_long ){
+ if( flag_long==2 ){
+ longvalue = va_arg(ap,u64);
+ }else{
+ longvalue = va_arg(ap,unsigned long int);
+ }
+ }else{
+ longvalue = va_arg(ap,unsigned int);
+ }
+ prefix = 0;
+ }
+ if( longvalue==0 ) flag_alternateform = 0;
+ if( flag_zeropad && precision=4 || (longvalue/10)%10==1 ){
+ x = 0;
+ }
+ *(--bufpt) = zOrd[x*2+1];
+ *(--bufpt) = zOrd[x*2];
+ }
+ {
+ const char *cset = &aDigits[infop->charset];
+ u8 base = infop->base;
+ do{ /* Convert to ascii */
+ *(--bufpt) = cset[longvalue%base];
+ longvalue = longvalue/base;
+ }while( longvalue>0 );
+ }
+ length = (int)(&zOut[nOut-1]-bufpt);
+ while( precision>length ){
+ *(--bufpt) = '0'; /* Zero pad */
+ length++;
+ }
+ if( cThousand ){
+ int nn = (length - 1)/3; /* Number of "," to insert */
+ int ix = (length - 1)%3 + 1;
+ bufpt -= nn;
+ for(idx=0; nn>0; idx++){
+ bufpt[idx] = bufpt[idx+nn];
+ ix--;
+ if( ix==0 ){
+ bufpt[++idx] = cThousand;
+ nn--;
+ ix = 3;
+ }
+ }
+ }
+ if( prefix ) *(--bufpt) = prefix; /* Add sign */
+ if( flag_alternateform && infop->prefix ){ /* Add "0" or "0x" */
+ const char *pre;
+ char x;
+ pre = &aPrefix[infop->prefix];
+ for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
+ }
+ length = (int)(&zOut[nOut-1]-bufpt);
+ break;
+ case etFLOAT:
+ case etEXP:
+ case etGENERIC:
+ if( bArgList ){
+ realvalue = getDoubleArg(pArgList);
+ }else{
+ realvalue = va_arg(ap,double);
+ }
+#ifdef SQLITE_OMIT_FLOATING_POINT
+ length = 0;
+#else
+ if( precision<0 ) precision = 6; /* Set default precision */
+ if( realvalue<0.0 ){
+ realvalue = -realvalue;
+ prefix = '-';
+ }else{
+ prefix = flag_prefix;
+ }
+ if( xtype==etGENERIC && precision>0 ) precision--;
+ testcase( precision>0xfff );
+ for(idx=precision&0xfff, rounder=0.5; idx>0; idx--, rounder*=0.1){}
+ if( xtype==etFLOAT ) realvalue += rounder;
+ /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
+ exp = 0;
+ if( sqlite3IsNaN((double)realvalue) ){
+ bufpt = "NaN";
+ length = 3;
+ break;
+ }
+ if( realvalue>0.0 ){
+ LONGDOUBLE_TYPE scale = 1.0;
+ while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
+ while( realvalue>=1e10*scale && exp<=350 ){ scale *= 1e10; exp+=10; }
+ while( realvalue>=10.0*scale && exp<=350 ){ scale *= 10.0; exp++; }
+ realvalue /= scale;
+ while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
+ while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
+ if( exp>350 ){
+ bufpt = buf;
+ buf[0] = prefix;
+ memcpy(buf+(prefix!=0),"Inf",4);
+ length = 3+(prefix!=0);
+ break;
+ }
+ }
+ bufpt = buf;
+ /*
+ ** If the field type is etGENERIC, then convert to either etEXP
+ ** or etFLOAT, as appropriate.
+ */
+ if( xtype!=etFLOAT ){
+ realvalue += rounder;
+ if( realvalue>=10.0 ){ realvalue *= 0.1; exp++; }
+ }
+ if( xtype==etGENERIC ){
+ flag_rtz = !flag_alternateform;
+ if( exp<-4 || exp>precision ){
+ xtype = etEXP;
+ }else{
+ precision = precision - exp;
+ xtype = etFLOAT;
+ }
+ }else{
+ flag_rtz = flag_altform2;
+ }
+ if( xtype==etEXP ){
+ e2 = 0;
+ }else{
+ e2 = exp;
+ }
+ if( MAX(e2,0)+(i64)precision+(i64)width > etBUFSIZE - 15 ){
+ bufpt = zExtra
+ = sqlite3Malloc( MAX(e2,0)+(i64)precision+(i64)width+15 );
+ if( bufpt==0 ){
+ setStrAccumError(pAccum, SQLITE_NOMEM);
+ return;
+ }
+ }
+ zOut = bufpt;
+ nsd = 16 + flag_altform2*10;
+ flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
+ /* The sign in front of the number */
+ if( prefix ){
+ *(bufpt++) = prefix;
+ }
+ /* Digits prior to the decimal point */
+ if( e2<0 ){
+ *(bufpt++) = '0';
+ }else{
+ for(; e2>=0; e2--){
+ *(bufpt++) = et_getdigit(&realvalue,&nsd);
+ }
+ }
+ /* The decimal point */
+ if( flag_dp ){
+ *(bufpt++) = '.';
+ }
+ /* "0" digits after the decimal point but before the first
+ ** significant digit of the number */
+ for(e2++; e2<0; precision--, e2++){
+ assert( precision>0 );
+ *(bufpt++) = '0';
+ }
+ /* Significant digits after the decimal point */
+ while( (precision--)>0 ){
+ *(bufpt++) = et_getdigit(&realvalue,&nsd);
+ }
+ /* Remove trailing zeros and the "." if no digits follow the "." */
+ if( flag_rtz && flag_dp ){
+ while( bufpt[-1]=='0' ) *(--bufpt) = 0;
+ assert( bufpt>zOut );
+ if( bufpt[-1]=='.' ){
+ if( flag_altform2 ){
+ *(bufpt++) = '0';
+ }else{
+ *(--bufpt) = 0;
+ }
+ }
+ }
+ /* Add the "eNNN" suffix */
+ if( xtype==etEXP ){
+ *(bufpt++) = aDigits[infop->charset];
+ if( exp<0 ){
+ *(bufpt++) = '-'; exp = -exp;
+ }else{
+ *(bufpt++) = '+';
+ }
+ if( exp>=100 ){
+ *(bufpt++) = (char)((exp/100)+'0'); /* 100's digit */
+ exp %= 100;
+ }
+ *(bufpt++) = (char)(exp/10+'0'); /* 10's digit */
+ *(bufpt++) = (char)(exp%10+'0'); /* 1's digit */
+ }
+ *bufpt = 0;
+
+ /* The converted number is in buf[] and zero terminated. Output it.
+ ** Note that the number is in the usual order, not reversed as with
+ ** integer conversions. */
+ length = (int)(bufpt-zOut);
+ bufpt = zOut;
+
+ /* Special case: Add leading zeros if the flag_zeropad flag is
+ ** set and we are not left justified */
+ if( flag_zeropad && !flag_leftjustify && length < width){
+ int i;
+ int nPad = width - length;
+ for(i=width; i>=nPad; i--){
+ bufpt[i] = bufpt[i-nPad];
+ }
+ i = prefix!=0;
+ while( nPad-- ) bufpt[i++] = '0';
+ length = width;
+ }
+#endif /* !defined(SQLITE_OMIT_FLOATING_POINT) */
+ break;
+ case etSIZE:
+ if( !bArgList ){
+ *(va_arg(ap,int*)) = pAccum->nChar;
+ }
+ length = width = 0;
+ break;
+ case etPERCENT:
+ buf[0] = '%';
+ bufpt = buf;
+ length = 1;
+ break;
+ case etCHARX:
+ if( bArgList ){
+ bufpt = getTextArg(pArgList);
+ length = 1;
+ if( bufpt ){
+ buf[0] = c = *(bufpt++);
+ if( (c&0xc0)==0xc0 ){
+ while( length<4 && (bufpt[0]&0xc0)==0x80 ){
+ buf[length++] = *(bufpt++);
+ }
+ }
+ }else{
+ buf[0] = 0;
+ }
+ }else{
+ unsigned int ch = va_arg(ap,unsigned int);
+ if( ch<0x00080 ){
+ buf[0] = ch & 0xff;
+ length = 1;
+ }else if( ch<0x00800 ){
+ buf[0] = 0xc0 + (u8)((ch>>6)&0x1f);
+ buf[1] = 0x80 + (u8)(ch & 0x3f);
+ length = 2;
+ }else if( ch<0x10000 ){
+ buf[0] = 0xe0 + (u8)((ch>>12)&0x0f);
+ buf[1] = 0x80 + (u8)((ch>>6) & 0x3f);
+ buf[2] = 0x80 + (u8)(ch & 0x3f);
+ length = 3;
+ }else{
+ buf[0] = 0xf0 + (u8)((ch>>18) & 0x07);
+ buf[1] = 0x80 + (u8)((ch>>12) & 0x3f);
+ buf[2] = 0x80 + (u8)((ch>>6) & 0x3f);
+ buf[3] = 0x80 + (u8)(ch & 0x3f);
+ length = 4;
+ }
+ }
+ if( precision>1 ){
+ width -= precision-1;
+ if( width>1 && !flag_leftjustify ){
+ sqlite3_str_appendchar(pAccum, width-1, ' ');
+ width = 0;
+ }
+ while( precision-- > 1 ){
+ sqlite3_str_append(pAccum, buf, length);
+ }
+ }
+ bufpt = buf;
+ flag_altform2 = 1;
+ goto adjust_width_for_utf8;
+ case etSTRING:
+ case etDYNSTRING:
+ if( bArgList ){
+ bufpt = getTextArg(pArgList);
+ xtype = etSTRING;
+ }else{
+ bufpt = va_arg(ap,char*);
+ }
+ if( bufpt==0 ){
+ bufpt = "";
+ }else if( xtype==etDYNSTRING ){
+ if( pAccum->nChar==0
+ && pAccum->mxAlloc
+ && width==0
+ && precision<0
+ && pAccum->accError==0
+ ){
+ /* Special optimization for sqlite3_mprintf("%z..."):
+ ** Extend an existing memory allocation rather than creating
+ ** a new one. */
+ assert( (pAccum->printfFlags&SQLITE_PRINTF_MALLOCED)==0 );
+ pAccum->zText = bufpt;
+ pAccum->nAlloc = sqlite3DbMallocSize(pAccum->db, bufpt);
+ pAccum->nChar = 0x7fffffff & (int)strlen(bufpt);
+ pAccum->printfFlags |= SQLITE_PRINTF_MALLOCED;
+ length = 0;
+ break;
+ }
+ zExtra = bufpt;
+ }
+ if( precision>=0 ){
+ if( flag_altform2 ){
+ /* Set length to the number of bytes needed in order to display
+ ** precision characters */
+ unsigned char *z = (unsigned char*)bufpt;
+ while( precision-- > 0 && z[0] ){
+ SQLITE_SKIP_UTF8(z);
+ }
+ length = (int)(z - (unsigned char*)bufpt);
+ }else{
+ for(length=0; length0 ){
+ /* Adjust width to account for extra bytes in UTF-8 characters */
+ int ii = length - 1;
+ while( ii>=0 ) if( (bufpt[ii--] & 0xc0)==0x80 ) width++;
+ }
+ break;
+ case etSQLESCAPE: /* %q: Escape ' characters */
+ case etSQLESCAPE2: /* %Q: Escape ' and enclose in '...' */
+ case etSQLESCAPE3: { /* %w: Escape " characters */
+ int i, j, k, n, isnull;
+ int needQuote;
+ char ch;
+ char q = ((xtype==etSQLESCAPE3)?'"':'\''); /* Quote character */
+ char *escarg;
+
+ if( bArgList ){
+ escarg = getTextArg(pArgList);
+ }else{
+ escarg = va_arg(ap,char*);
+ }
+ isnull = escarg==0;
+ if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
+ /* For %q, %Q, and %w, the precision is the number of byte (or
+ ** characters if the ! flags is present) to use from the input.
+ ** Because of the extra quoting characters inserted, the number
+ ** of output characters may be larger than the precision.
+ */
+ k = precision;
+ for(i=n=0; k!=0 && (ch=escarg[i])!=0; i++, k--){
+ if( ch==q ) n++;
+ if( flag_altform2 && (ch&0xc0)==0xc0 ){
+ while( (escarg[i+1]&0xc0)==0x80 ){ i++; }
+ }
+ }
+ needQuote = !isnull && xtype==etSQLESCAPE2;
+ n += i + 3;
+ if( n>etBUFSIZE ){
+ bufpt = zExtra = sqlite3Malloc( n );
+ if( bufpt==0 ){
+ setStrAccumError(pAccum, SQLITE_NOMEM);
+ return;
+ }
+ }else{
+ bufpt = buf;
+ }
+ j = 0;
+ if( needQuote ) bufpt[j++] = q;
+ k = i;
+ for(i=0; iprintfFlags & SQLITE_PRINTF_INTERNAL)==0 ) return;
+ pToken = va_arg(ap, Token*);
+ assert( bArgList==0 );
+ if( pToken && pToken->n ){
+ sqlite3_str_append(pAccum, (const char*)pToken->z, pToken->n);
+ }
+ length = width = 0;
+ break;
+ }
+ case etSRCLIST: {
+ SrcList *pSrc;
+ int k;
+ struct SrcList_item *pItem;
+ if( (pAccum->printfFlags & SQLITE_PRINTF_INTERNAL)==0 ) return;
+ pSrc = va_arg(ap, SrcList*);
+ k = va_arg(ap, int);
+ pItem = &pSrc->a[k];
+ assert( bArgList==0 );
+ assert( k>=0 && knSrc );
+ if( pItem->zDatabase ){
+ sqlite3_str_appendall(pAccum, pItem->zDatabase);
+ sqlite3_str_append(pAccum, ".", 1);
+ }
+ sqlite3_str_appendall(pAccum, pItem->zName);
+ length = width = 0;
+ break;
+ }
+ default: {
+ assert( xtype==etINVALID );
+ return;
+ }
+ }/* End switch over the format type */
+ /*
+ ** The text of the conversion is pointed to by "bufpt" and is
+ ** "length" characters long. The field width is "width". Do
+ ** the output. Both length and width are in bytes, not characters,
+ ** at this point. If the "!" flag was present on string conversions
+ ** indicating that width and precision should be expressed in characters,
+ ** then the values have been translated prior to reaching this point.
+ */
+ width -= length;
+ if( width>0 ){
+ if( !flag_leftjustify ) sqlite3_str_appendchar(pAccum, width, ' ');
+ sqlite3_str_append(pAccum, bufpt, length);
+ if( flag_leftjustify ) sqlite3_str_appendchar(pAccum, width, ' ');
+ }else{
+ sqlite3_str_append(pAccum, bufpt, length);
+ }
+
+ if( zExtra ){
+ sqlite3DbFree(pAccum->db, zExtra);
+ zExtra = 0;
+ }
+ }/* End for loop over the format string */
+} /* End of function */
+
+/*
+** Enlarge the memory allocation on a StrAccum object so that it is
+** able to accept at least N more bytes of text.
+**
+** Return the number of bytes of text that StrAccum is able to accept
+** after the attempted enlargement. The value returned might be zero.
+*/
+static int sqlite3StrAccumEnlarge(StrAccum *p, int N){
+ char *zNew;
+ assert( p->nChar+(i64)N >= p->nAlloc ); /* Only called if really needed */
+ if( p->accError ){
+ testcase(p->accError==SQLITE_TOOBIG);
+ testcase(p->accError==SQLITE_NOMEM);
+ return 0;
+ }
+ if( p->mxAlloc==0 ){
+ N = p->nAlloc - p->nChar - 1;
+ setStrAccumError(p, SQLITE_TOOBIG);
+ return N;
+ }else{
+ char *zOld = isMalloced(p) ? p->zText : 0;
+ i64 szNew = p->nChar;
+ szNew += N + 1;
+ if( szNew+p->nChar<=p->mxAlloc ){
+ /* Force exponential buffer size growth as long as it does not overflow,
+ ** to avoid having to call this routine too often */
+ szNew += p->nChar;
+ }
+ if( szNew > p->mxAlloc ){
+ sqlite3_str_reset(p);
+ setStrAccumError(p, SQLITE_TOOBIG);
+ return 0;
+ }else{
+ p->nAlloc = (int)szNew;
+ }
+ if( p->db ){
+ zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
+ }else{
+ zNew = sqlite3_realloc64(zOld, p->nAlloc);
+ }
+ if( zNew ){
+ assert( p->zText!=0 || p->nChar==0 );
+ if( !isMalloced(p) && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
+ p->zText = zNew;
+ p->nAlloc = sqlite3DbMallocSize(p->db, zNew);
+ p->printfFlags |= SQLITE_PRINTF_MALLOCED;
+ }else{
+ sqlite3_str_reset(p);
+ setStrAccumError(p, SQLITE_NOMEM);
+ return 0;
+ }
+ }
+ return N;
+}
+
+/*
+** Append N copies of character c to the given string buffer.
+*/
+SQLITE_API void sqlite3_str_appendchar(sqlite3_str *p, int N, char c){
+ testcase( p->nChar + (i64)N > 0x7fffffff );
+ if( p->nChar+(i64)N >= p->nAlloc && (N = sqlite3StrAccumEnlarge(p, N))<=0 ){
+ return;
+ }
+ while( (N--)>0 ) p->zText[p->nChar++] = c;
+}
+
+/*
+** The StrAccum "p" is not large enough to accept N new bytes of z[].
+** So enlarge if first, then do the append.
+**
+** This is a helper routine to sqlite3_str_append() that does special-case
+** work (enlarging the buffer) using tail recursion, so that the
+** sqlite3_str_append() routine can use fast calling semantics.
+*/
+static void SQLITE_NOINLINE enlargeAndAppend(StrAccum *p, const char *z, int N){
+ N = sqlite3StrAccumEnlarge(p, N);
+ if( N>0 ){
+ memcpy(&p->zText[p->nChar], z, N);
+ p->nChar += N;
+ }
+}
+
+/*
+** Append N bytes of text from z to the StrAccum object. Increase the
+** size of the memory allocation for StrAccum if necessary.
+*/
+SQLITE_API void sqlite3_str_append(sqlite3_str *p, const char *z, int N){
+ assert( z!=0 || N==0 );
+ assert( p->zText!=0 || p->nChar==0 || p->accError );
+ assert( N>=0 );
+ assert( p->accError==0 || p->nAlloc==0 );
+ if( p->nChar+N >= p->nAlloc ){
+ enlargeAndAppend(p,z,N);
+ }else if( N ){
+ assert( p->zText );
+ p->nChar += N;
+ memcpy(&p->zText[p->nChar-N], z, N);
+ }
+}
+
+/*
+** Append the complete text of zero-terminated string z[] to the p string.
+*/
+SQLITE_API void sqlite3_str_appendall(sqlite3_str *p, const char *z){
+ sqlite3_str_append(p, z, sqlite3Strlen30(z));
+}
+
+
+/*
+** Finish off a string by making sure it is zero-terminated.
+** Return a pointer to the resulting string. Return a NULL
+** pointer if any kind of error was encountered.
+*/
+static SQLITE_NOINLINE char *strAccumFinishRealloc(StrAccum *p){
+ char *zText;
+ assert( p->mxAlloc>0 && !isMalloced(p) );
+ zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
+ if( zText ){
+ memcpy(zText, p->zText, p->nChar+1);
+ p->printfFlags |= SQLITE_PRINTF_MALLOCED;
+ }else{
+ setStrAccumError(p, SQLITE_NOMEM);
+ }
+ p->zText = zText;
+ return zText;
+}
+SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum *p){
+ if( p->zText ){
+ p->zText[p->nChar] = 0;
+ if( p->mxAlloc>0 && !isMalloced(p) ){
+ return strAccumFinishRealloc(p);
+ }
+ }
+ return p->zText;
+}
+
+/*
+** This singleton is an sqlite3_str object that is returned if
+** sqlite3_malloc() fails to provide space for a real one. This
+** sqlite3_str object accepts no new text and always returns
+** an SQLITE_NOMEM error.
+*/
+static sqlite3_str sqlite3OomStr = {
+ 0, 0, 0, 0, 0, SQLITE_NOMEM, 0
+};
+
+/* Finalize a string created using sqlite3_str_new().
+*/
+SQLITE_API char *sqlite3_str_finish(sqlite3_str *p){
+ char *z;
+ if( p!=0 && p!=&sqlite3OomStr ){
+ z = sqlite3StrAccumFinish(p);
+ sqlite3_free(p);
+ }else{
+ z = 0;
+ }
+ return z;
+}
+
+/* Return any error code associated with p */
+SQLITE_API int sqlite3_str_errcode(sqlite3_str *p){
+ return p ? p->accError : SQLITE_NOMEM;
+}
+
+/* Return the current length of p in bytes */
+SQLITE_API int sqlite3_str_length(sqlite3_str *p){
+ return p ? p->nChar : 0;
+}
+
+/* Return the current value for p */
+SQLITE_API char *sqlite3_str_value(sqlite3_str *p){
+ if( p==0 || p->nChar==0 ) return 0;
+ p->zText[p->nChar] = 0;
+ return p->zText;
+}
+
+/*
+** Reset an StrAccum string. Reclaim all malloced memory.
+*/
+SQLITE_API void sqlite3_str_reset(StrAccum *p){
+ if( isMalloced(p) ){
+ sqlite3DbFree(p->db, p->zText);
+ p->printfFlags &= ~SQLITE_PRINTF_MALLOCED;
+ }
+ p->nAlloc = 0;
+ p->nChar = 0;
+ p->zText = 0;
+}
+
+/*
+** Initialize a string accumulator.
+**
+** p: The accumulator to be initialized.
+** db: Pointer to a database connection. May be NULL. Lookaside
+** memory is used if not NULL. db->mallocFailed is set appropriately
+** when not NULL.
+** zBase: An initial buffer. May be NULL in which case the initial buffer
+** is malloced.
+** n: Size of zBase in bytes. If total space requirements never exceed
+** n then no memory allocations ever occur.
+** mx: Maximum number of bytes to accumulate. If mx==0 then no memory
+** allocations will ever occur.
+*/
+SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum *p, sqlite3 *db, char *zBase, int n, int mx){
+ p->zText = zBase;
+ p->db = db;
+ p->nAlloc = n;
+ p->mxAlloc = mx;
+ p->nChar = 0;
+ p->accError = 0;
+ p->printfFlags = 0;
+}
+
+/* Allocate and initialize a new dynamic string object */
+SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3 *db){
+ sqlite3_str *p = sqlite3_malloc64(sizeof(*p));
+ if( p ){
+ sqlite3StrAccumInit(p, 0, 0, 0,
+ db ? db->aLimit[SQLITE_LIMIT_LENGTH] : SQLITE_MAX_LENGTH);
+ }else{
+ p = &sqlite3OomStr;
+ }
+ return p;
+}
+
+/*
+** Print into memory obtained from sqliteMalloc(). Use the internal
+** %-conversion extensions.
+*/
+SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
+ char *z;
+ char zBase[SQLITE_PRINT_BUF_SIZE];
+ StrAccum acc;
+ assert( db!=0 );
+ sqlite3StrAccumInit(&acc, db, zBase, sizeof(zBase),
+ db->aLimit[SQLITE_LIMIT_LENGTH]);
+ acc.printfFlags = SQLITE_PRINTF_INTERNAL;
+ sqlite3_str_vappendf(&acc, zFormat, ap);
+ z = sqlite3StrAccumFinish(&acc);
+ if( acc.accError==SQLITE_NOMEM ){
+ sqlite3OomFault(db);
+ }
+ return z;
+}
+
+/*
+** Print into memory obtained from sqliteMalloc(). Use the internal
+** %-conversion extensions.
+*/
+SQLITE_PRIVATE char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
+ va_list ap;
+ char *z;
+ va_start(ap, zFormat);
+ z = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ return z;
+}
+
+/*
+** Print into memory obtained from sqlite3_malloc(). Omit the internal
+** %-conversion extensions.
+*/
+SQLITE_API char *sqlite3_vmprintf(const char *zFormat, va_list ap){
+ char *z;
+ char zBase[SQLITE_PRINT_BUF_SIZE];
+ StrAccum acc;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( zFormat==0 ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ sqlite3StrAccumInit(&acc, 0, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
+ sqlite3_str_vappendf(&acc, zFormat, ap);
+ z = sqlite3StrAccumFinish(&acc);
+ return z;
+}
+
+/*
+** Print into memory obtained from sqlite3_malloc()(). Omit the internal
+** %-conversion extensions.
+*/
+SQLITE_API char *sqlite3_mprintf(const char *zFormat, ...){
+ va_list ap;
+ char *z;
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ va_start(ap, zFormat);
+ z = sqlite3_vmprintf(zFormat, ap);
+ va_end(ap);
+ return z;
+}
+
+/*
+** sqlite3_snprintf() works like snprintf() except that it ignores the
+** current locale settings. This is important for SQLite because we
+** are not able to use a "," as the decimal point in place of "." as
+** specified by some locales.
+**
+** Oops: The first two arguments of sqlite3_snprintf() are backwards
+** from the snprintf() standard. Unfortunately, it is too late to change
+** this without breaking compatibility, so we just have to live with the
+** mistake.
+**
+** sqlite3_vsnprintf() is the varargs version.
+*/
+SQLITE_API char *sqlite3_vsnprintf(int n, char *zBuf, const char *zFormat, va_list ap){
+ StrAccum acc;
+ if( n<=0 ) return zBuf;
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( zBuf==0 || zFormat==0 ) {
+ (void)SQLITE_MISUSE_BKPT;
+ if( zBuf ) zBuf[0] = 0;
+ return zBuf;
+ }
+#endif
+ sqlite3StrAccumInit(&acc, 0, zBuf, n, 0);
+ sqlite3_str_vappendf(&acc, zFormat, ap);
+ zBuf[acc.nChar] = 0;
+ return zBuf;
+}
+SQLITE_API char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
+ char *z;
+ va_list ap;
+ va_start(ap,zFormat);
+ z = sqlite3_vsnprintf(n, zBuf, zFormat, ap);
+ va_end(ap);
+ return z;
+}
+
+/*
+** This is the routine that actually formats the sqlite3_log() message.
+** We house it in a separate routine from sqlite3_log() to avoid using
+** stack space on small-stack systems when logging is disabled.
+**
+** sqlite3_log() must render into a static buffer. It cannot dynamically
+** allocate memory because it might be called while the memory allocator
+** mutex is held.
+**
+** sqlite3_str_vappendf() might ask for *temporary* memory allocations for
+** certain format characters (%q) or for very large precisions or widths.
+** Care must be taken that any sqlite3_log() calls that occur while the
+** memory mutex is held do not use these mechanisms.
+*/
+static void renderLogMsg(int iErrCode, const char *zFormat, va_list ap){
+ StrAccum acc; /* String accumulator */
+ char zMsg[SQLITE_PRINT_BUF_SIZE*3]; /* Complete log message */
+
+ sqlite3StrAccumInit(&acc, 0, zMsg, sizeof(zMsg), 0);
+ sqlite3_str_vappendf(&acc, zFormat, ap);
+ sqlite3GlobalConfig.xLog(sqlite3GlobalConfig.pLogArg, iErrCode,
+ sqlite3StrAccumFinish(&acc));
+}
+
+/*
+** Format and write a message to the log if logging is enabled.
+*/
+SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...){
+ va_list ap; /* Vararg list */
+ if( sqlite3GlobalConfig.xLog ){
+ va_start(ap, zFormat);
+ renderLogMsg(iErrCode, zFormat, ap);
+ va_end(ap);
+ }
+}
+
+#if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
+/*
+** A version of printf() that understands %lld. Used for debugging.
+** The printf() built into some versions of windows does not understand %lld
+** and segfaults if you give it a long long int.
+*/
+SQLITE_PRIVATE void sqlite3DebugPrintf(const char *zFormat, ...){
+ va_list ap;
+ StrAccum acc;
+ char zBuf[500];
+ sqlite3StrAccumInit(&acc, 0, zBuf, sizeof(zBuf), 0);
+ va_start(ap,zFormat);
+ sqlite3_str_vappendf(&acc, zFormat, ap);
+ va_end(ap);
+ sqlite3StrAccumFinish(&acc);
+#ifdef SQLITE_OS_TRACE_PROC
+ {
+ extern void SQLITE_OS_TRACE_PROC(const char *zBuf, int nBuf);
+ SQLITE_OS_TRACE_PROC(zBuf, sizeof(zBuf));
+ }
+#else
+ fprintf(stdout,"%s", zBuf);
+ fflush(stdout);
+#endif
+}
+#endif
+
+
+/*
+** variable-argument wrapper around sqlite3_str_vappendf(). The bFlags argument
+** can contain the bit SQLITE_PRINTF_INTERNAL enable internal formats.
+*/
+SQLITE_API void sqlite3_str_appendf(StrAccum *p, const char *zFormat, ...){
+ va_list ap;
+ va_start(ap,zFormat);
+ sqlite3_str_vappendf(p, zFormat, ap);
+ va_end(ap);
+}
+
+/************** End of printf.c **********************************************/
+/************** Begin file treeview.c ****************************************/
+/*
+** 2015-06-08
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains C code to implement the TreeView debugging routines.
+** These routines print a parse tree to standard output for debugging and
+** analysis.
+**
+** The interfaces in this file is only available when compiling
+** with SQLITE_DEBUG.
+*/
+/* #include "sqliteInt.h" */
+#ifdef SQLITE_DEBUG
+
+/*
+** Add a new subitem to the tree. The moreToFollow flag indicates that this
+** is not the last item in the tree.
+*/
+static TreeView *sqlite3TreeViewPush(TreeView *p, u8 moreToFollow){
+ if( p==0 ){
+ p = sqlite3_malloc64( sizeof(*p) );
+ if( p==0 ) return 0;
+ memset(p, 0, sizeof(*p));
+ }else{
+ p->iLevel++;
+ }
+ assert( moreToFollow==0 || moreToFollow==1 );
+ if( p->iLevelbLine) ) p->bLine[p->iLevel] = moreToFollow;
+ return p;
+}
+
+/*
+** Finished with one layer of the tree
+*/
+static void sqlite3TreeViewPop(TreeView *p){
+ if( p==0 ) return;
+ p->iLevel--;
+ if( p->iLevel<0 ) sqlite3_free(p);
+}
+
+/*
+** Generate a single line of output for the tree, with a prefix that contains
+** all the appropriate tree lines
+*/
+static void sqlite3TreeViewLine(TreeView *p, const char *zFormat, ...){
+ va_list ap;
+ int i;
+ StrAccum acc;
+ char zBuf[500];
+ sqlite3StrAccumInit(&acc, 0, zBuf, sizeof(zBuf), 0);
+ if( p ){
+ for(i=0; iiLevel && ibLine)-1; i++){
+ sqlite3_str_append(&acc, p->bLine[i] ? "| " : " ", 4);
+ }
+ sqlite3_str_append(&acc, p->bLine[i] ? "|-- " : "'-- ", 4);
+ }
+ if( zFormat!=0 ){
+ va_start(ap, zFormat);
+ sqlite3_str_vappendf(&acc, zFormat, ap);
+ va_end(ap);
+ assert( acc.nChar>0 );
+ sqlite3_str_append(&acc, "\n", 1);
+ }
+ sqlite3StrAccumFinish(&acc);
+ fprintf(stdout,"%s", zBuf);
+ fflush(stdout);
+}
+
+/*
+** Shorthand for starting a new tree item that consists of a single label
+*/
+static void sqlite3TreeViewItem(TreeView *p, const char *zLabel,u8 moreFollows){
+ p = sqlite3TreeViewPush(p, moreFollows);
+ sqlite3TreeViewLine(p, "%s", zLabel);
+}
+
+/*
+** Generate a human-readable description of a WITH clause.
+*/
+SQLITE_PRIVATE void sqlite3TreeViewWith(TreeView *pView, const With *pWith, u8 moreToFollow){
+ int i;
+ if( pWith==0 ) return;
+ if( pWith->nCte==0 ) return;
+ if( pWith->pOuter ){
+ sqlite3TreeViewLine(pView, "WITH (0x%p, pOuter=0x%p)",pWith,pWith->pOuter);
+ }else{
+ sqlite3TreeViewLine(pView, "WITH (0x%p)", pWith);
+ }
+ if( pWith->nCte>0 ){
+ pView = sqlite3TreeViewPush(pView, 1);
+ for(i=0; inCte; i++){
+ StrAccum x;
+ char zLine[1000];
+ const struct Cte *pCte = &pWith->a[i];
+ sqlite3StrAccumInit(&x, 0, zLine, sizeof(zLine), 0);
+ sqlite3_str_appendf(&x, "%s", pCte->zName);
+ if( pCte->pCols && pCte->pCols->nExpr>0 ){
+ char cSep = '(';
+ int j;
+ for(j=0; jpCols->nExpr; j++){
+ sqlite3_str_appendf(&x, "%c%s", cSep, pCte->pCols->a[j].zName);
+ cSep = ',';
+ }
+ sqlite3_str_appendf(&x, ")");
+ }
+ sqlite3_str_appendf(&x, " AS");
+ sqlite3StrAccumFinish(&x);
+ sqlite3TreeViewItem(pView, zLine, inCte-1);
+ sqlite3TreeViewSelect(pView, pCte->pSelect, 0);
+ sqlite3TreeViewPop(pView);
+ }
+ sqlite3TreeViewPop(pView);
+ }
+}
+
+
+/*
+** Generate a human-readable description of a Select object.
+*/
+SQLITE_PRIVATE void sqlite3TreeViewSelect(TreeView *pView, const Select *p, u8 moreToFollow){
+ int n = 0;
+ int cnt = 0;
+ if( p==0 ){
+ sqlite3TreeViewLine(pView, "nil-SELECT");
+ return;
+ }
+ pView = sqlite3TreeViewPush(pView, moreToFollow);
+ if( p->pWith ){
+ sqlite3TreeViewWith(pView, p->pWith, 1);
+ cnt = 1;
+ sqlite3TreeViewPush(pView, 1);
+ }
+ do{
+ sqlite3TreeViewLine(pView,
+ "SELECT%s%s (%u/%p) selFlags=0x%x nSelectRow=%d",
+ ((p->selFlags & SF_Distinct) ? " DISTINCT" : ""),
+ ((p->selFlags & SF_Aggregate) ? " agg_flag" : ""),
+ p->selId, p, p->selFlags,
+ (int)p->nSelectRow
+ );
+ if( cnt++ ) sqlite3TreeViewPop(pView);
+ if( p->pPrior ){
+ n = 1000;
+ }else{
+ n = 0;
+ if( p->pSrc && p->pSrc->nSrc ) n++;
+ if( p->pWhere ) n++;
+ if( p->pGroupBy ) n++;
+ if( p->pHaving ) n++;
+ if( p->pOrderBy ) n++;
+ if( p->pLimit ) n++;
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ if( p->pWin ) n++;
+ if( p->pWinDefn ) n++;
+#endif
+ }
+ sqlite3TreeViewExprList(pView, p->pEList, (n--)>0, "result-set");
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ if( p->pWin ){
+ Window *pX;
+ pView = sqlite3TreeViewPush(pView, (n--)>0);
+ sqlite3TreeViewLine(pView, "window-functions");
+ for(pX=p->pWin; pX; pX=pX->pNextWin){
+ sqlite3TreeViewWinFunc(pView, pX, pX->pNextWin!=0);
+ }
+ sqlite3TreeViewPop(pView);
+ }
+#endif
+ if( p->pSrc && p->pSrc->nSrc ){
+ int i;
+ pView = sqlite3TreeViewPush(pView, (n--)>0);
+ sqlite3TreeViewLine(pView, "FROM");
+ for(i=0; ipSrc->nSrc; i++){
+ struct SrcList_item *pItem = &p->pSrc->a[i];
+ StrAccum x;
+ char zLine[100];
+ sqlite3StrAccumInit(&x, 0, zLine, sizeof(zLine), 0);
+ sqlite3_str_appendf(&x, "{%d,*}", pItem->iCursor);
+ if( pItem->zDatabase ){
+ sqlite3_str_appendf(&x, " %s.%s", pItem->zDatabase, pItem->zName);
+ }else if( pItem->zName ){
+ sqlite3_str_appendf(&x, " %s", pItem->zName);
+ }
+ if( pItem->pTab ){
+ sqlite3_str_appendf(&x, " tabname=%Q", pItem->pTab->zName);
+ }
+ if( pItem->zAlias ){
+ sqlite3_str_appendf(&x, " (AS %s)", pItem->zAlias);
+ }
+ if( pItem->fg.jointype & JT_LEFT ){
+ sqlite3_str_appendf(&x, " LEFT-JOIN");
+ }
+ sqlite3StrAccumFinish(&x);
+ sqlite3TreeViewItem(pView, zLine, ipSrc->nSrc-1);
+ if( pItem->pSelect ){
+ sqlite3TreeViewSelect(pView, pItem->pSelect, 0);
+ }
+ if( pItem->fg.isTabFunc ){
+ sqlite3TreeViewExprList(pView, pItem->u1.pFuncArg, 0, "func-args:");
+ }
+ sqlite3TreeViewPop(pView);
+ }
+ sqlite3TreeViewPop(pView);
+ }
+ if( p->pWhere ){
+ sqlite3TreeViewItem(pView, "WHERE", (n--)>0);
+ sqlite3TreeViewExpr(pView, p->pWhere, 0);
+ sqlite3TreeViewPop(pView);
+ }
+ if( p->pGroupBy ){
+ sqlite3TreeViewExprList(pView, p->pGroupBy, (n--)>0, "GROUPBY");
+ }
+ if( p->pHaving ){
+ sqlite3TreeViewItem(pView, "HAVING", (n--)>0);
+ sqlite3TreeViewExpr(pView, p->pHaving, 0);
+ sqlite3TreeViewPop(pView);
+ }
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ if( p->pWinDefn ){
+ Window *pX;
+ sqlite3TreeViewItem(pView, "WINDOW", (n--)>0);
+ for(pX=p->pWinDefn; pX; pX=pX->pNextWin){
+ sqlite3TreeViewWindow(pView, pX, pX->pNextWin!=0);
+ }
+ sqlite3TreeViewPop(pView);
+ }
+#endif
+ if( p->pOrderBy ){
+ sqlite3TreeViewExprList(pView, p->pOrderBy, (n--)>0, "ORDERBY");
+ }
+ if( p->pLimit ){
+ sqlite3TreeViewItem(pView, "LIMIT", (n--)>0);
+ sqlite3TreeViewExpr(pView, p->pLimit->pLeft, p->pLimit->pRight!=0);
+ if( p->pLimit->pRight ){
+ sqlite3TreeViewItem(pView, "OFFSET", (n--)>0);
+ sqlite3TreeViewExpr(pView, p->pLimit->pRight, 0);
+ sqlite3TreeViewPop(pView);
+ }
+ sqlite3TreeViewPop(pView);
+ }
+ if( p->pPrior ){
+ const char *zOp = "UNION";
+ switch( p->op ){
+ case TK_ALL: zOp = "UNION ALL"; break;
+ case TK_INTERSECT: zOp = "INTERSECT"; break;
+ case TK_EXCEPT: zOp = "EXCEPT"; break;
+ }
+ sqlite3TreeViewItem(pView, zOp, 1);
+ }
+ p = p->pPrior;
+ }while( p!=0 );
+ sqlite3TreeViewPop(pView);
+}
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+/*
+** Generate a description of starting or stopping bounds
+*/
+SQLITE_PRIVATE void sqlite3TreeViewBound(
+ TreeView *pView, /* View context */
+ u8 eBound, /* UNBOUNDED, CURRENT, PRECEDING, FOLLOWING */
+ Expr *pExpr, /* Value for PRECEDING or FOLLOWING */
+ u8 moreToFollow /* True if more to follow */
+){
+ switch( eBound ){
+ case TK_UNBOUNDED: {
+ sqlite3TreeViewItem(pView, "UNBOUNDED", moreToFollow);
+ sqlite3TreeViewPop(pView);
+ break;
+ }
+ case TK_CURRENT: {
+ sqlite3TreeViewItem(pView, "CURRENT", moreToFollow);
+ sqlite3TreeViewPop(pView);
+ break;
+ }
+ case TK_PRECEDING: {
+ sqlite3TreeViewItem(pView, "PRECEDING", moreToFollow);
+ sqlite3TreeViewExpr(pView, pExpr, 0);
+ sqlite3TreeViewPop(pView);
+ break;
+ }
+ case TK_FOLLOWING: {
+ sqlite3TreeViewItem(pView, "FOLLOWING", moreToFollow);
+ sqlite3TreeViewExpr(pView, pExpr, 0);
+ sqlite3TreeViewPop(pView);
+ break;
+ }
+ }
+}
+#endif /* SQLITE_OMIT_WINDOWFUNC */
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+/*
+** Generate a human-readable explanation for a Window object
+*/
+SQLITE_PRIVATE void sqlite3TreeViewWindow(TreeView *pView, const Window *pWin, u8 more){
+ pView = sqlite3TreeViewPush(pView, more);
+ if( pWin->zName ){
+ sqlite3TreeViewLine(pView, "OVER %s", pWin->zName);
+ }else{
+ sqlite3TreeViewLine(pView, "OVER");
+ }
+ if( pWin->pPartition ){
+ sqlite3TreeViewExprList(pView, pWin->pPartition, 1, "PARTITION-BY");
+ }
+ if( pWin->pOrderBy ){
+ sqlite3TreeViewExprList(pView, pWin->pOrderBy, 1, "ORDER-BY");
+ }
+ if( pWin->eType ){
+ sqlite3TreeViewItem(pView, pWin->eType==TK_RANGE ? "RANGE" : "ROWS", 0);
+ sqlite3TreeViewBound(pView, pWin->eStart, pWin->pStart, 1);
+ sqlite3TreeViewBound(pView, pWin->eEnd, pWin->pEnd, 0);
+ sqlite3TreeViewPop(pView);
+ }
+ sqlite3TreeViewPop(pView);
+}
+#endif /* SQLITE_OMIT_WINDOWFUNC */
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+/*
+** Generate a human-readable explanation for a Window Function object
+*/
+SQLITE_PRIVATE void sqlite3TreeViewWinFunc(TreeView *pView, const Window *pWin, u8 more){
+ pView = sqlite3TreeViewPush(pView, more);
+ sqlite3TreeViewLine(pView, "WINFUNC %s(%d)",
+ pWin->pFunc->zName, pWin->pFunc->nArg);
+ sqlite3TreeViewWindow(pView, pWin, 0);
+ sqlite3TreeViewPop(pView);
+}
+#endif /* SQLITE_OMIT_WINDOWFUNC */
+
+/*
+** Generate a human-readable explanation of an expression tree.
+*/
+SQLITE_PRIVATE void sqlite3TreeViewExpr(TreeView *pView, const Expr *pExpr, u8 moreToFollow){
+ const char *zBinOp = 0; /* Binary operator */
+ const char *zUniOp = 0; /* Unary operator */
+ char zFlgs[60];
+ pView = sqlite3TreeViewPush(pView, moreToFollow);
+ if( pExpr==0 ){
+ sqlite3TreeViewLine(pView, "nil");
+ sqlite3TreeViewPop(pView);
+ return;
+ }
+ if( pExpr->flags ){
+ if( ExprHasProperty(pExpr, EP_FromJoin) ){
+ sqlite3_snprintf(sizeof(zFlgs),zFlgs," flags=0x%x iRJT=%d",
+ pExpr->flags, pExpr->iRightJoinTable);
+ }else{
+ sqlite3_snprintf(sizeof(zFlgs),zFlgs," flags=0x%x",pExpr->flags);
+ }
+ }else{
+ zFlgs[0] = 0;
+ }
+ switch( pExpr->op ){
+ case TK_AGG_COLUMN: {
+ sqlite3TreeViewLine(pView, "AGG{%d:%d}%s",
+ pExpr->iTable, pExpr->iColumn, zFlgs);
+ break;
+ }
+ case TK_COLUMN: {
+ if( pExpr->iTable<0 ){
+ /* This only happens when coding check constraints */
+ sqlite3TreeViewLine(pView, "COLUMN(%d)%s", pExpr->iColumn, zFlgs);
+ }else{
+ sqlite3TreeViewLine(pView, "{%d:%d}%s",
+ pExpr->iTable, pExpr->iColumn, zFlgs);
+ }
+ if( ExprHasProperty(pExpr, EP_FixedCol) ){
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
+ }
+ break;
+ }
+ case TK_INTEGER: {
+ if( pExpr->flags & EP_IntValue ){
+ sqlite3TreeViewLine(pView, "%d", pExpr->u.iValue);
+ }else{
+ sqlite3TreeViewLine(pView, "%s", pExpr->u.zToken);
+ }
+ break;
+ }
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ case TK_FLOAT: {
+ sqlite3TreeViewLine(pView,"%s", pExpr->u.zToken);
+ break;
+ }
+#endif
+ case TK_STRING: {
+ sqlite3TreeViewLine(pView,"%Q", pExpr->u.zToken);
+ break;
+ }
+ case TK_NULL: {
+ sqlite3TreeViewLine(pView,"NULL");
+ break;
+ }
+ case TK_TRUEFALSE: {
+ sqlite3TreeViewLine(pView,
+ sqlite3ExprTruthValue(pExpr) ? "TRUE" : "FALSE");
+ break;
+ }
+#ifndef SQLITE_OMIT_BLOB_LITERAL
+ case TK_BLOB: {
+ sqlite3TreeViewLine(pView,"%s", pExpr->u.zToken);
+ break;
+ }
+#endif
+ case TK_VARIABLE: {
+ sqlite3TreeViewLine(pView,"VARIABLE(%s,%d)",
+ pExpr->u.zToken, pExpr->iColumn);
+ break;
+ }
+ case TK_REGISTER: {
+ sqlite3TreeViewLine(pView,"REGISTER(%d)", pExpr->iTable);
+ break;
+ }
+ case TK_ID: {
+ sqlite3TreeViewLine(pView,"ID \"%w\"", pExpr->u.zToken);
+ break;
+ }
+#ifndef SQLITE_OMIT_CAST
+ case TK_CAST: {
+ /* Expressions of the form: CAST(pLeft AS token) */
+ sqlite3TreeViewLine(pView,"CAST %Q", pExpr->u.zToken);
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
+ break;
+ }
+#endif /* SQLITE_OMIT_CAST */
+ case TK_LT: zBinOp = "LT"; break;
+ case TK_LE: zBinOp = "LE"; break;
+ case TK_GT: zBinOp = "GT"; break;
+ case TK_GE: zBinOp = "GE"; break;
+ case TK_NE: zBinOp = "NE"; break;
+ case TK_EQ: zBinOp = "EQ"; break;
+ case TK_IS: zBinOp = "IS"; break;
+ case TK_ISNOT: zBinOp = "ISNOT"; break;
+ case TK_AND: zBinOp = "AND"; break;
+ case TK_OR: zBinOp = "OR"; break;
+ case TK_PLUS: zBinOp = "ADD"; break;
+ case TK_STAR: zBinOp = "MUL"; break;
+ case TK_MINUS: zBinOp = "SUB"; break;
+ case TK_REM: zBinOp = "REM"; break;
+ case TK_BITAND: zBinOp = "BITAND"; break;
+ case TK_BITOR: zBinOp = "BITOR"; break;
+ case TK_SLASH: zBinOp = "DIV"; break;
+ case TK_LSHIFT: zBinOp = "LSHIFT"; break;
+ case TK_RSHIFT: zBinOp = "RSHIFT"; break;
+ case TK_CONCAT: zBinOp = "CONCAT"; break;
+ case TK_DOT: zBinOp = "DOT"; break;
+
+ case TK_UMINUS: zUniOp = "UMINUS"; break;
+ case TK_UPLUS: zUniOp = "UPLUS"; break;
+ case TK_BITNOT: zUniOp = "BITNOT"; break;
+ case TK_NOT: zUniOp = "NOT"; break;
+ case TK_ISNULL: zUniOp = "ISNULL"; break;
+ case TK_NOTNULL: zUniOp = "NOTNULL"; break;
+
+ case TK_TRUTH: {
+ int x;
+ const char *azOp[] = {
+ "IS-FALSE", "IS-TRUE", "IS-NOT-FALSE", "IS-NOT-TRUE"
+ };
+ assert( pExpr->op2==TK_IS || pExpr->op2==TK_ISNOT );
+ assert( pExpr->pRight );
+ assert( pExpr->pRight->op==TK_TRUEFALSE );
+ x = (pExpr->op2==TK_ISNOT)*2 + sqlite3ExprTruthValue(pExpr->pRight);
+ zUniOp = azOp[x];
+ break;
+ }
+
+ case TK_SPAN: {
+ sqlite3TreeViewLine(pView, "SPAN %Q", pExpr->u.zToken);
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
+ break;
+ }
+
+ case TK_COLLATE: {
+ sqlite3TreeViewLine(pView, "COLLATE %Q", pExpr->u.zToken);
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
+ break;
+ }
+
+ case TK_AGG_FUNCTION:
+ case TK_FUNCTION: {
+ ExprList *pFarg; /* List of function arguments */
+ Window *pWin;
+ if( ExprHasProperty(pExpr, EP_TokenOnly) ){
+ pFarg = 0;
+ pWin = 0;
+ }else{
+ pFarg = pExpr->x.pList;
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ pWin = pExpr->pWin;
+#else
+ pWin = 0;
+#endif
+ }
+ if( pExpr->op==TK_AGG_FUNCTION ){
+ sqlite3TreeViewLine(pView, "AGG_FUNCTION%d %Q",
+ pExpr->op2, pExpr->u.zToken);
+ }else{
+ sqlite3TreeViewLine(pView, "FUNCTION %Q", pExpr->u.zToken);
+ }
+ if( pFarg ){
+ sqlite3TreeViewExprList(pView, pFarg, pWin!=0, 0);
+ }
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ if( pWin ){
+ sqlite3TreeViewWindow(pView, pWin, 0);
+ }
+#endif
+ break;
+ }
+#ifndef SQLITE_OMIT_SUBQUERY
+ case TK_EXISTS: {
+ sqlite3TreeViewLine(pView, "EXISTS-expr flags=0x%x", pExpr->flags);
+ sqlite3TreeViewSelect(pView, pExpr->x.pSelect, 0);
+ break;
+ }
+ case TK_SELECT: {
+ sqlite3TreeViewLine(pView, "SELECT-expr flags=0x%x", pExpr->flags);
+ sqlite3TreeViewSelect(pView, pExpr->x.pSelect, 0);
+ break;
+ }
+ case TK_IN: {
+ sqlite3TreeViewLine(pView, "IN flags=0x%x", pExpr->flags);
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 1);
+ if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+ sqlite3TreeViewSelect(pView, pExpr->x.pSelect, 0);
+ }else{
+ sqlite3TreeViewExprList(pView, pExpr->x.pList, 0, 0);
+ }
+ break;
+ }
+#endif /* SQLITE_OMIT_SUBQUERY */
+
+ /*
+ ** x BETWEEN y AND z
+ **
+ ** This is equivalent to
+ **
+ ** x>=y AND x<=z
+ **
+ ** X is stored in pExpr->pLeft.
+ ** Y is stored in pExpr->pList->a[0].pExpr.
+ ** Z is stored in pExpr->pList->a[1].pExpr.
+ */
+ case TK_BETWEEN: {
+ Expr *pX = pExpr->pLeft;
+ Expr *pY = pExpr->x.pList->a[0].pExpr;
+ Expr *pZ = pExpr->x.pList->a[1].pExpr;
+ sqlite3TreeViewLine(pView, "BETWEEN");
+ sqlite3TreeViewExpr(pView, pX, 1);
+ sqlite3TreeViewExpr(pView, pY, 1);
+ sqlite3TreeViewExpr(pView, pZ, 0);
+ break;
+ }
+ case TK_TRIGGER: {
+ /* If the opcode is TK_TRIGGER, then the expression is a reference
+ ** to a column in the new.* or old.* pseudo-tables available to
+ ** trigger programs. In this case Expr.iTable is set to 1 for the
+ ** new.* pseudo-table, or 0 for the old.* pseudo-table. Expr.iColumn
+ ** is set to the column of the pseudo-table to read, or to -1 to
+ ** read the rowid field.
+ */
+ sqlite3TreeViewLine(pView, "%s(%d)",
+ pExpr->iTable ? "NEW" : "OLD", pExpr->iColumn);
+ break;
+ }
+ case TK_CASE: {
+ sqlite3TreeViewLine(pView, "CASE");
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 1);
+ sqlite3TreeViewExprList(pView, pExpr->x.pList, 0, 0);
+ break;
+ }
+#ifndef SQLITE_OMIT_TRIGGER
+ case TK_RAISE: {
+ const char *zType = "unk";
+ switch( pExpr->affinity ){
+ case OE_Rollback: zType = "rollback"; break;
+ case OE_Abort: zType = "abort"; break;
+ case OE_Fail: zType = "fail"; break;
+ case OE_Ignore: zType = "ignore"; break;
+ }
+ sqlite3TreeViewLine(pView, "RAISE %s(%Q)", zType, pExpr->u.zToken);
+ break;
+ }
+#endif
+ case TK_MATCH: {
+ sqlite3TreeViewLine(pView, "MATCH {%d:%d}%s",
+ pExpr->iTable, pExpr->iColumn, zFlgs);
+ sqlite3TreeViewExpr(pView, pExpr->pRight, 0);
+ break;
+ }
+ case TK_VECTOR: {
+ sqlite3TreeViewBareExprList(pView, pExpr->x.pList, "VECTOR");
+ break;
+ }
+ case TK_SELECT_COLUMN: {
+ sqlite3TreeViewLine(pView, "SELECT-COLUMN %d", pExpr->iColumn);
+ sqlite3TreeViewSelect(pView, pExpr->pLeft->x.pSelect, 0);
+ break;
+ }
+ case TK_IF_NULL_ROW: {
+ sqlite3TreeViewLine(pView, "IF-NULL-ROW %d", pExpr->iTable);
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
+ break;
+ }
+ default: {
+ sqlite3TreeViewLine(pView, "op=%d", pExpr->op);
+ break;
+ }
+ }
+ if( zBinOp ){
+ sqlite3TreeViewLine(pView, "%s%s", zBinOp, zFlgs);
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 1);
+ sqlite3TreeViewExpr(pView, pExpr->pRight, 0);
+ }else if( zUniOp ){
+ sqlite3TreeViewLine(pView, "%s%s", zUniOp, zFlgs);
+ sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
+ }
+ sqlite3TreeViewPop(pView);
+}
+
+
+/*
+** Generate a human-readable explanation of an expression list.
+*/
+SQLITE_PRIVATE void sqlite3TreeViewBareExprList(
+ TreeView *pView,
+ const ExprList *pList,
+ const char *zLabel
+){
+ if( zLabel==0 || zLabel[0]==0 ) zLabel = "LIST";
+ if( pList==0 ){
+ sqlite3TreeViewLine(pView, "%s (empty)", zLabel);
+ }else{
+ int i;
+ sqlite3TreeViewLine(pView, "%s", zLabel);
+ for(i=0; inExpr; i++){
+ int j = pList->a[i].u.x.iOrderByCol;
+ char *zName = pList->a[i].zName;
+ int moreToFollow = inExpr - 1;
+ if( j || zName ){
+ sqlite3TreeViewPush(pView, moreToFollow);
+ moreToFollow = 0;
+ sqlite3TreeViewLine(pView, 0);
+ if( zName ){
+ fprintf(stdout, "AS %s ", zName);
+ }
+ if( j ){
+ fprintf(stdout, "iOrderByCol=%d", j);
+ }
+ fprintf(stdout, "\n");
+ fflush(stdout);
+ }
+ sqlite3TreeViewExpr(pView, pList->a[i].pExpr, moreToFollow);
+ if( j || zName ){
+ sqlite3TreeViewPop(pView);
+ }
+ }
+ }
+}
+SQLITE_PRIVATE void sqlite3TreeViewExprList(
+ TreeView *pView,
+ const ExprList *pList,
+ u8 moreToFollow,
+ const char *zLabel
+){
+ pView = sqlite3TreeViewPush(pView, moreToFollow);
+ sqlite3TreeViewBareExprList(pView, pList, zLabel);
+ sqlite3TreeViewPop(pView);
+}
+
+#endif /* SQLITE_DEBUG */
+
+/************** End of treeview.c ********************************************/
+/************** Begin file random.c ******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code to implement a pseudo-random number
+** generator (PRNG) for SQLite.
+**
+** Random numbers are used by some of the database backends in order
+** to generate random integer keys for tables or random filenames.
+*/
+/* #include "sqliteInt.h" */
+
+
+/* All threads share a single random number generator.
+** This structure is the current state of the generator.
+*/
+static SQLITE_WSD struct sqlite3PrngType {
+ unsigned char isInit; /* True if initialized */
+ unsigned char i, j; /* State variables */
+ unsigned char s[256]; /* State variables */
+} sqlite3Prng;
+
+/*
+** Return N random bytes.
+*/
+SQLITE_API void sqlite3_randomness(int N, void *pBuf){
+ unsigned char t;
+ unsigned char *zBuf = pBuf;
+
+ /* The "wsdPrng" macro will resolve to the pseudo-random number generator
+ ** state vector. If writable static data is unsupported on the target,
+ ** we have to locate the state vector at run-time. In the more common
+ ** case where writable static data is supported, wsdPrng can refer directly
+ ** to the "sqlite3Prng" state vector declared above.
+ */
+#ifdef SQLITE_OMIT_WSD
+ struct sqlite3PrngType *p = &GLOBAL(struct sqlite3PrngType, sqlite3Prng);
+# define wsdPrng p[0]
+#else
+# define wsdPrng sqlite3Prng
+#endif
+
+#if SQLITE_THREADSAFE
+ sqlite3_mutex *mutex;
+#endif
+
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return;
+#endif
+
+#if SQLITE_THREADSAFE
+ mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
+#endif
+
+ sqlite3_mutex_enter(mutex);
+ if( N<=0 || pBuf==0 ){
+ wsdPrng.isInit = 0;
+ sqlite3_mutex_leave(mutex);
+ return;
+ }
+
+ /* Initialize the state of the random number generator once,
+ ** the first time this routine is called. The seed value does
+ ** not need to contain a lot of randomness since we are not
+ ** trying to do secure encryption or anything like that...
+ **
+ ** Nothing in this file or anywhere else in SQLite does any kind of
+ ** encryption. The RC4 algorithm is being used as a PRNG (pseudo-random
+ ** number generator) not as an encryption device.
+ */
+ if( !wsdPrng.isInit ){
+ int i;
+ char k[256];
+ wsdPrng.j = 0;
+ wsdPrng.i = 0;
+ sqlite3OsRandomness(sqlite3_vfs_find(0), 256, k);
+ for(i=0; i<256; i++){
+ wsdPrng.s[i] = (u8)i;
+ }
+ for(i=0; i<256; i++){
+ wsdPrng.j += wsdPrng.s[i] + k[i];
+ t = wsdPrng.s[wsdPrng.j];
+ wsdPrng.s[wsdPrng.j] = wsdPrng.s[i];
+ wsdPrng.s[i] = t;
+ }
+ wsdPrng.isInit = 1;
+ }
+
+ assert( N>0 );
+ do{
+ wsdPrng.i++;
+ t = wsdPrng.s[wsdPrng.i];
+ wsdPrng.j += t;
+ wsdPrng.s[wsdPrng.i] = wsdPrng.s[wsdPrng.j];
+ wsdPrng.s[wsdPrng.j] = t;
+ t += wsdPrng.s[wsdPrng.i];
+ *(zBuf++) = wsdPrng.s[t];
+ }while( --N );
+ sqlite3_mutex_leave(mutex);
+}
+
+#ifndef SQLITE_UNTESTABLE
+/*
+** For testing purposes, we sometimes want to preserve the state of
+** PRNG and restore the PRNG to its saved state at a later time, or
+** to reset the PRNG to its initial state. These routines accomplish
+** those tasks.
+**
+** The sqlite3_test_control() interface calls these routines to
+** control the PRNG.
+*/
+static SQLITE_WSD struct sqlite3PrngType sqlite3SavedPrng;
+SQLITE_PRIVATE void sqlite3PrngSaveState(void){
+ memcpy(
+ &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
+ &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
+ sizeof(sqlite3Prng)
+ );
+}
+SQLITE_PRIVATE void sqlite3PrngRestoreState(void){
+ memcpy(
+ &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
+ &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
+ sizeof(sqlite3Prng)
+ );
+}
+#endif /* SQLITE_UNTESTABLE */
+
+/************** End of random.c **********************************************/
+/************** Begin file threads.c *****************************************/
+/*
+** 2012 July 21
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file presents a simple cross-platform threading interface for
+** use internally by SQLite.
+**
+** A "thread" can be created using sqlite3ThreadCreate(). This thread
+** runs independently of its creator until it is joined using
+** sqlite3ThreadJoin(), at which point it terminates.
+**
+** Threads do not have to be real. It could be that the work of the
+** "thread" is done by the main thread at either the sqlite3ThreadCreate()
+** or sqlite3ThreadJoin() call. This is, in fact, what happens in
+** single threaded systems. Nothing in SQLite requires multiple threads.
+** This interface exists so that applications that want to take advantage
+** of multiple cores can do so, while also allowing applications to stay
+** single-threaded if desired.
+*/
+/* #include "sqliteInt.h" */
+#if SQLITE_OS_WIN
+/* # include "os_win.h" */
+#endif
+
+#if SQLITE_MAX_WORKER_THREADS>0
+
+/********************************* Unix Pthreads ****************************/
+#if SQLITE_OS_UNIX && defined(SQLITE_MUTEX_PTHREADS) && SQLITE_THREADSAFE>0
+
+#define SQLITE_THREADS_IMPLEMENTED 1 /* Prevent the single-thread code below */
+/* #include */
+
+/* A running thread */
+struct SQLiteThread {
+ pthread_t tid; /* Thread ID */
+ int done; /* Set to true when thread finishes */
+ void *pOut; /* Result returned by the thread */
+ void *(*xTask)(void*); /* The thread routine */
+ void *pIn; /* Argument to the thread */
+};
+
+/* Create a new thread */
+SQLITE_PRIVATE int sqlite3ThreadCreate(
+ SQLiteThread **ppThread, /* OUT: Write the thread object here */
+ void *(*xTask)(void*), /* Routine to run in a separate thread */
+ void *pIn /* Argument passed into xTask() */
+){
+ SQLiteThread *p;
+ int rc;
+
+ assert( ppThread!=0 );
+ assert( xTask!=0 );
+ /* This routine is never used in single-threaded mode */
+ assert( sqlite3GlobalConfig.bCoreMutex!=0 );
+
+ *ppThread = 0;
+ p = sqlite3Malloc(sizeof(*p));
+ if( p==0 ) return SQLITE_NOMEM_BKPT;
+ memset(p, 0, sizeof(*p));
+ p->xTask = xTask;
+ p->pIn = pIn;
+ /* If the SQLITE_TESTCTRL_FAULT_INSTALL callback is registered to a
+ ** function that returns SQLITE_ERROR when passed the argument 200, that
+ ** forces worker threads to run sequentially and deterministically
+ ** for testing purposes. */
+ if( sqlite3FaultSim(200) ){
+ rc = 1;
+ }else{
+ rc = pthread_create(&p->tid, 0, xTask, pIn);
+ }
+ if( rc ){
+ p->done = 1;
+ p->pOut = xTask(pIn);
+ }
+ *ppThread = p;
+ return SQLITE_OK;
+}
+
+/* Get the results of the thread */
+SQLITE_PRIVATE int sqlite3ThreadJoin(SQLiteThread *p, void **ppOut){
+ int rc;
+
+ assert( ppOut!=0 );
+ if( NEVER(p==0) ) return SQLITE_NOMEM_BKPT;
+ if( p->done ){
+ *ppOut = p->pOut;
+ rc = SQLITE_OK;
+ }else{
+ rc = pthread_join(p->tid, ppOut) ? SQLITE_ERROR : SQLITE_OK;
+ }
+ sqlite3_free(p);
+ return rc;
+}
+
+#endif /* SQLITE_OS_UNIX && defined(SQLITE_MUTEX_PTHREADS) */
+/******************************** End Unix Pthreads *************************/
+
+
+/********************************* Win32 Threads ****************************/
+#if SQLITE_OS_WIN_THREADS
+
+#define SQLITE_THREADS_IMPLEMENTED 1 /* Prevent the single-thread code below */
+#include
+
+/* A running thread */
+struct SQLiteThread {
+ void *tid; /* The thread handle */
+ unsigned id; /* The thread identifier */
+ void *(*xTask)(void*); /* The routine to run as a thread */
+ void *pIn; /* Argument to xTask */
+ void *pResult; /* Result of xTask */
+};
+
+/* Thread procedure Win32 compatibility shim */
+static unsigned __stdcall sqlite3ThreadProc(
+ void *pArg /* IN: Pointer to the SQLiteThread structure */
+){
+ SQLiteThread *p = (SQLiteThread *)pArg;
+
+ assert( p!=0 );
+#if 0
+ /*
+ ** This assert appears to trigger spuriously on certain
+ ** versions of Windows, possibly due to _beginthreadex()
+ ** and/or CreateThread() not fully setting their thread
+ ** ID parameter before starting the thread.
+ */
+ assert( p->id==GetCurrentThreadId() );
+#endif
+ assert( p->xTask!=0 );
+ p->pResult = p->xTask(p->pIn);
+
+ _endthreadex(0);
+ return 0; /* NOT REACHED */
+}
+
+/* Create a new thread */
+SQLITE_PRIVATE int sqlite3ThreadCreate(
+ SQLiteThread **ppThread, /* OUT: Write the thread object here */
+ void *(*xTask)(void*), /* Routine to run in a separate thread */
+ void *pIn /* Argument passed into xTask() */
+){
+ SQLiteThread *p;
+
+ assert( ppThread!=0 );
+ assert( xTask!=0 );
+ *ppThread = 0;
+ p = sqlite3Malloc(sizeof(*p));
+ if( p==0 ) return SQLITE_NOMEM_BKPT;
+ /* If the SQLITE_TESTCTRL_FAULT_INSTALL callback is registered to a
+ ** function that returns SQLITE_ERROR when passed the argument 200, that
+ ** forces worker threads to run sequentially and deterministically
+ ** (via the sqlite3FaultSim() term of the conditional) for testing
+ ** purposes. */
+ if( sqlite3GlobalConfig.bCoreMutex==0 || sqlite3FaultSim(200) ){
+ memset(p, 0, sizeof(*p));
+ }else{
+ p->xTask = xTask;
+ p->pIn = pIn;
+ p->tid = (void*)_beginthreadex(0, 0, sqlite3ThreadProc, p, 0, &p->id);
+ if( p->tid==0 ){
+ memset(p, 0, sizeof(*p));
+ }
+ }
+ if( p->xTask==0 ){
+ p->id = GetCurrentThreadId();
+ p->pResult = xTask(pIn);
+ }
+ *ppThread = p;
+ return SQLITE_OK;
+}
+
+SQLITE_PRIVATE DWORD sqlite3Win32Wait(HANDLE hObject); /* os_win.c */
+
+/* Get the results of the thread */
+SQLITE_PRIVATE int sqlite3ThreadJoin(SQLiteThread *p, void **ppOut){
+ DWORD rc;
+ BOOL bRc;
+
+ assert( ppOut!=0 );
+ if( NEVER(p==0) ) return SQLITE_NOMEM_BKPT;
+ if( p->xTask==0 ){
+ /* assert( p->id==GetCurrentThreadId() ); */
+ rc = WAIT_OBJECT_0;
+ assert( p->tid==0 );
+ }else{
+ assert( p->id!=0 && p->id!=GetCurrentThreadId() );
+ rc = sqlite3Win32Wait((HANDLE)p->tid);
+ assert( rc!=WAIT_IO_COMPLETION );
+ bRc = CloseHandle((HANDLE)p->tid);
+ assert( bRc );
+ }
+ if( rc==WAIT_OBJECT_0 ) *ppOut = p->pResult;
+ sqlite3_free(p);
+ return (rc==WAIT_OBJECT_0) ? SQLITE_OK : SQLITE_ERROR;
+}
+
+#endif /* SQLITE_OS_WIN_THREADS */
+/******************************** End Win32 Threads *************************/
+
+
+/********************************* Single-Threaded **************************/
+#ifndef SQLITE_THREADS_IMPLEMENTED
+/*
+** This implementation does not actually create a new thread. It does the
+** work of the thread in the main thread, when either the thread is created
+** or when it is joined
+*/
+
+/* A running thread */
+struct SQLiteThread {
+ void *(*xTask)(void*); /* The routine to run as a thread */
+ void *pIn; /* Argument to xTask */
+ void *pResult; /* Result of xTask */
+};
+
+/* Create a new thread */
+SQLITE_PRIVATE int sqlite3ThreadCreate(
+ SQLiteThread **ppThread, /* OUT: Write the thread object here */
+ void *(*xTask)(void*), /* Routine to run in a separate thread */
+ void *pIn /* Argument passed into xTask() */
+){
+ SQLiteThread *p;
+
+ assert( ppThread!=0 );
+ assert( xTask!=0 );
+ *ppThread = 0;
+ p = sqlite3Malloc(sizeof(*p));
+ if( p==0 ) return SQLITE_NOMEM_BKPT;
+ if( (SQLITE_PTR_TO_INT(p)/17)&1 ){
+ p->xTask = xTask;
+ p->pIn = pIn;
+ }else{
+ p->xTask = 0;
+ p->pResult = xTask(pIn);
+ }
+ *ppThread = p;
+ return SQLITE_OK;
+}
+
+/* Get the results of the thread */
+SQLITE_PRIVATE int sqlite3ThreadJoin(SQLiteThread *p, void **ppOut){
+
+ assert( ppOut!=0 );
+ if( NEVER(p==0) ) return SQLITE_NOMEM_BKPT;
+ if( p->xTask ){
+ *ppOut = p->xTask(p->pIn);
+ }else{
+ *ppOut = p->pResult;
+ }
+ sqlite3_free(p);
+
+#if defined(SQLITE_TEST)
+ {
+ void *pTstAlloc = sqlite3Malloc(10);
+ if (!pTstAlloc) return SQLITE_NOMEM_BKPT;
+ sqlite3_free(pTstAlloc);
+ }
+#endif
+
+ return SQLITE_OK;
+}
+
+#endif /* !defined(SQLITE_THREADS_IMPLEMENTED) */
+/****************************** End Single-Threaded *************************/
+#endif /* SQLITE_MAX_WORKER_THREADS>0 */
+
+/************** End of threads.c *********************************************/
+/************** Begin file utf.c *********************************************/
+/*
+** 2004 April 13
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains routines used to translate between UTF-8,
+** UTF-16, UTF-16BE, and UTF-16LE.
+**
+** Notes on UTF-8:
+**
+** Byte-0 Byte-1 Byte-2 Byte-3 Value
+** 0xxxxxxx 00000000 00000000 0xxxxxxx
+** 110yyyyy 10xxxxxx 00000000 00000yyy yyxxxxxx
+** 1110zzzz 10yyyyyy 10xxxxxx 00000000 zzzzyyyy yyxxxxxx
+** 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx 000uuuuu zzzzyyyy yyxxxxxx
+**
+**
+** Notes on UTF-16: (with wwww+1==uuuuu)
+**
+** Word-0 Word-1 Value
+** 110110ww wwzzzzyy 110111yy yyxxxxxx 000uuuuu zzzzyyyy yyxxxxxx
+** zzzzyyyy yyxxxxxx 00000000 zzzzyyyy yyxxxxxx
+**
+**
+** BOM or Byte Order Mark:
+** 0xff 0xfe little-endian utf-16 follows
+** 0xfe 0xff big-endian utf-16 follows
+**
+*/
+/* #include "sqliteInt.h" */
+/* #include */
+/* #include "vdbeInt.h" */
+
+#if !defined(SQLITE_AMALGAMATION) && SQLITE_BYTEORDER==0
+/*
+** The following constant value is used by the SQLITE_BIGENDIAN and
+** SQLITE_LITTLEENDIAN macros.
+*/
+SQLITE_PRIVATE const int sqlite3one = 1;
+#endif /* SQLITE_AMALGAMATION && SQLITE_BYTEORDER==0 */
+
+/*
+** This lookup table is used to help decode the first byte of
+** a multi-byte UTF8 character.
+*/
+static const unsigned char sqlite3Utf8Trans1[] = {
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+ 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00,
+};
+
+
+#define WRITE_UTF8(zOut, c) { \
+ if( c<0x00080 ){ \
+ *zOut++ = (u8)(c&0xFF); \
+ } \
+ else if( c<0x00800 ){ \
+ *zOut++ = 0xC0 + (u8)((c>>6)&0x1F); \
+ *zOut++ = 0x80 + (u8)(c & 0x3F); \
+ } \
+ else if( c<0x10000 ){ \
+ *zOut++ = 0xE0 + (u8)((c>>12)&0x0F); \
+ *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); \
+ *zOut++ = 0x80 + (u8)(c & 0x3F); \
+ }else{ \
+ *zOut++ = 0xF0 + (u8)((c>>18) & 0x07); \
+ *zOut++ = 0x80 + (u8)((c>>12) & 0x3F); \
+ *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); \
+ *zOut++ = 0x80 + (u8)(c & 0x3F); \
+ } \
+}
+
+#define WRITE_UTF16LE(zOut, c) { \
+ if( c<=0xFFFF ){ \
+ *zOut++ = (u8)(c&0x00FF); \
+ *zOut++ = (u8)((c>>8)&0x00FF); \
+ }else{ \
+ *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \
+ *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03)); \
+ *zOut++ = (u8)(c&0x00FF); \
+ *zOut++ = (u8)(0x00DC + ((c>>8)&0x03)); \
+ } \
+}
+
+#define WRITE_UTF16BE(zOut, c) { \
+ if( c<=0xFFFF ){ \
+ *zOut++ = (u8)((c>>8)&0x00FF); \
+ *zOut++ = (u8)(c&0x00FF); \
+ }else{ \
+ *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03)); \
+ *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \
+ *zOut++ = (u8)(0x00DC + ((c>>8)&0x03)); \
+ *zOut++ = (u8)(c&0x00FF); \
+ } \
+}
+
+#define READ_UTF16LE(zIn, TERM, c){ \
+ c = (*zIn++); \
+ c += ((*zIn++)<<8); \
+ if( c>=0xD800 && c<0xE000 && TERM ){ \
+ int c2 = (*zIn++); \
+ c2 += ((*zIn++)<<8); \
+ c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \
+ } \
+}
+
+#define READ_UTF16BE(zIn, TERM, c){ \
+ c = ((*zIn++)<<8); \
+ c += (*zIn++); \
+ if( c>=0xD800 && c<0xE000 && TERM ){ \
+ int c2 = ((*zIn++)<<8); \
+ c2 += (*zIn++); \
+ c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \
+ } \
+}
+
+/*
+** Translate a single UTF-8 character. Return the unicode value.
+**
+** During translation, assume that the byte that zTerm points
+** is a 0x00.
+**
+** Write a pointer to the next unread byte back into *pzNext.
+**
+** Notes On Invalid UTF-8:
+**
+** * This routine never allows a 7-bit character (0x00 through 0x7f) to
+** be encoded as a multi-byte character. Any multi-byte character that
+** attempts to encode a value between 0x00 and 0x7f is rendered as 0xfffd.
+**
+** * This routine never allows a UTF16 surrogate value to be encoded.
+** If a multi-byte character attempts to encode a value between
+** 0xd800 and 0xe000 then it is rendered as 0xfffd.
+**
+** * Bytes in the range of 0x80 through 0xbf which occur as the first
+** byte of a character are interpreted as single-byte characters
+** and rendered as themselves even though they are technically
+** invalid characters.
+**
+** * This routine accepts over-length UTF8 encodings
+** for unicode values 0x80 and greater. It does not change over-length
+** encodings to 0xfffd as some systems recommend.
+*/
+#define READ_UTF8(zIn, zTerm, c) \
+ c = *(zIn++); \
+ if( c>=0xc0 ){ \
+ c = sqlite3Utf8Trans1[c-0xc0]; \
+ while( zIn!=zTerm && (*zIn & 0xc0)==0x80 ){ \
+ c = (c<<6) + (0x3f & *(zIn++)); \
+ } \
+ if( c<0x80 \
+ || (c&0xFFFFF800)==0xD800 \
+ || (c&0xFFFFFFFE)==0xFFFE ){ c = 0xFFFD; } \
+ }
+SQLITE_PRIVATE u32 sqlite3Utf8Read(
+ const unsigned char **pz /* Pointer to string from which to read char */
+){
+ unsigned int c;
+
+ /* Same as READ_UTF8() above but without the zTerm parameter.
+ ** For this routine, we assume the UTF8 string is always zero-terminated.
+ */
+ c = *((*pz)++);
+ if( c>=0xc0 ){
+ c = sqlite3Utf8Trans1[c-0xc0];
+ while( (*(*pz) & 0xc0)==0x80 ){
+ c = (c<<6) + (0x3f & *((*pz)++));
+ }
+ if( c<0x80
+ || (c&0xFFFFF800)==0xD800
+ || (c&0xFFFFFFFE)==0xFFFE ){ c = 0xFFFD; }
+ }
+ return c;
+}
+
+
+
+
+/*
+** If the TRANSLATE_TRACE macro is defined, the value of each Mem is
+** printed on stderr on the way into and out of sqlite3VdbeMemTranslate().
+*/
+/* #define TRANSLATE_TRACE 1 */
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** This routine transforms the internal text encoding used by pMem to
+** desiredEnc. It is an error if the string is already of the desired
+** encoding, or if *pMem does not contain a string value.
+*/
+SQLITE_PRIVATE SQLITE_NOINLINE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
+ int len; /* Maximum length of output string in bytes */
+ unsigned char *zOut; /* Output buffer */
+ unsigned char *zIn; /* Input iterator */
+ unsigned char *zTerm; /* End of input */
+ unsigned char *z; /* Output iterator */
+ unsigned int c;
+
+ assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+ assert( pMem->flags&MEM_Str );
+ assert( pMem->enc!=desiredEnc );
+ assert( pMem->enc!=0 );
+ assert( pMem->n>=0 );
+
+#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
+ {
+ char zBuf[100];
+ sqlite3VdbeMemPrettyPrint(pMem, zBuf);
+ fprintf(stderr, "INPUT: %s\n", zBuf);
+ }
+#endif
+
+ /* If the translation is between UTF-16 little and big endian, then
+ ** all that is required is to swap the byte order. This case is handled
+ ** differently from the others.
+ */
+ if( pMem->enc!=SQLITE_UTF8 && desiredEnc!=SQLITE_UTF8 ){
+ u8 temp;
+ int rc;
+ rc = sqlite3VdbeMemMakeWriteable(pMem);
+ if( rc!=SQLITE_OK ){
+ assert( rc==SQLITE_NOMEM );
+ return SQLITE_NOMEM_BKPT;
+ }
+ zIn = (u8*)pMem->z;
+ zTerm = &zIn[pMem->n&~1];
+ while( zInenc = desiredEnc;
+ goto translate_out;
+ }
+
+ /* Set len to the maximum number of bytes required in the output buffer. */
+ if( desiredEnc==SQLITE_UTF8 ){
+ /* When converting from UTF-16, the maximum growth results from
+ ** translating a 2-byte character to a 4-byte UTF-8 character.
+ ** A single byte is required for the output string
+ ** nul-terminator.
+ */
+ pMem->n &= ~1;
+ len = pMem->n * 2 + 1;
+ }else{
+ /* When converting from UTF-8 to UTF-16 the maximum growth is caused
+ ** when a 1-byte UTF-8 character is translated into a 2-byte UTF-16
+ ** character. Two bytes are required in the output buffer for the
+ ** nul-terminator.
+ */
+ len = pMem->n * 2 + 2;
+ }
+
+ /* Set zIn to point at the start of the input buffer and zTerm to point 1
+ ** byte past the end.
+ **
+ ** Variable zOut is set to point at the output buffer, space obtained
+ ** from sqlite3_malloc().
+ */
+ zIn = (u8*)pMem->z;
+ zTerm = &zIn[pMem->n];
+ zOut = sqlite3DbMallocRaw(pMem->db, len);
+ if( !zOut ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ z = zOut;
+
+ if( pMem->enc==SQLITE_UTF8 ){
+ if( desiredEnc==SQLITE_UTF16LE ){
+ /* UTF-8 -> UTF-16 Little-endian */
+ while( zIn UTF-16 Big-endian */
+ while( zInn = (int)(z - zOut);
+ *z++ = 0;
+ }else{
+ assert( desiredEnc==SQLITE_UTF8 );
+ if( pMem->enc==SQLITE_UTF16LE ){
+ /* UTF-16 Little-endian -> UTF-8 */
+ while( zIn UTF-8 */
+ while( zInn = (int)(z - zOut);
+ }
+ *z = 0;
+ assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len );
+
+ c = pMem->flags;
+ sqlite3VdbeMemRelease(pMem);
+ pMem->flags = MEM_Str|MEM_Term|(c&(MEM_AffMask|MEM_Subtype));
+ pMem->enc = desiredEnc;
+ pMem->z = (char*)zOut;
+ pMem->zMalloc = pMem->z;
+ pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->z);
+
+translate_out:
+#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
+ {
+ char zBuf[100];
+ sqlite3VdbeMemPrettyPrint(pMem, zBuf);
+ fprintf(stderr, "OUTPUT: %s\n", zBuf);
+ }
+#endif
+ return SQLITE_OK;
+}
+#endif /* SQLITE_OMIT_UTF16 */
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** This routine checks for a byte-order mark at the beginning of the
+** UTF-16 string stored in *pMem. If one is present, it is removed and
+** the encoding of the Mem adjusted. This routine does not do any
+** byte-swapping, it just sets Mem.enc appropriately.
+**
+** The allocation (static, dynamic etc.) and encoding of the Mem may be
+** changed by this function.
+*/
+SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem){
+ int rc = SQLITE_OK;
+ u8 bom = 0;
+
+ assert( pMem->n>=0 );
+ if( pMem->n>1 ){
+ u8 b1 = *(u8 *)pMem->z;
+ u8 b2 = *(((u8 *)pMem->z) + 1);
+ if( b1==0xFE && b2==0xFF ){
+ bom = SQLITE_UTF16BE;
+ }
+ if( b1==0xFF && b2==0xFE ){
+ bom = SQLITE_UTF16LE;
+ }
+ }
+
+ if( bom ){
+ rc = sqlite3VdbeMemMakeWriteable(pMem);
+ if( rc==SQLITE_OK ){
+ pMem->n -= 2;
+ memmove(pMem->z, &pMem->z[2], pMem->n);
+ pMem->z[pMem->n] = '\0';
+ pMem->z[pMem->n+1] = '\0';
+ pMem->flags |= MEM_Term;
+ pMem->enc = bom;
+ }
+ }
+ return rc;
+}
+#endif /* SQLITE_OMIT_UTF16 */
+
+/*
+** pZ is a UTF-8 encoded unicode string. If nByte is less than zero,
+** return the number of unicode characters in pZ up to (but not including)
+** the first 0x00 byte. If nByte is not less than zero, return the
+** number of unicode characters in the first nByte of pZ (or up to
+** the first 0x00, whichever comes first).
+*/
+SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *zIn, int nByte){
+ int r = 0;
+ const u8 *z = (const u8*)zIn;
+ const u8 *zTerm;
+ if( nByte>=0 ){
+ zTerm = &z[nByte];
+ }else{
+ zTerm = (const u8*)(-1);
+ }
+ assert( z<=zTerm );
+ while( *z!=0 && zmallocFailed ){
+ sqlite3VdbeMemRelease(&m);
+ m.z = 0;
+ }
+ assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
+ assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
+ assert( m.z || db->mallocFailed );
+ return m.z;
+}
+
+/*
+** zIn is a UTF-16 encoded unicode string at least nChar characters long.
+** Return the number of bytes in the first nChar unicode characters
+** in pZ. nChar must be non-negative.
+*/
+SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
+ int c;
+ unsigned char const *z = zIn;
+ int n = 0;
+
+ if( SQLITE_UTF16NATIVE==SQLITE_UTF16BE ){
+ while( n0 && n<=4 );
+ z[0] = 0;
+ z = zBuf;
+ c = sqlite3Utf8Read((const u8**)&z);
+ t = i;
+ if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
+ if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
+ assert( c==t );
+ assert( (z-zBuf)==n );
+ }
+ for(i=0; i<0x00110000; i++){
+ if( i>=0xD800 && i<0xE000 ) continue;
+ z = zBuf;
+ WRITE_UTF16LE(z, i);
+ n = (int)(z-zBuf);
+ assert( n>0 && n<=4 );
+ z[0] = 0;
+ z = zBuf;
+ READ_UTF16LE(z, 1, c);
+ assert( c==i );
+ assert( (z-zBuf)==n );
+ }
+ for(i=0; i<0x00110000; i++){
+ if( i>=0xD800 && i<0xE000 ) continue;
+ z = zBuf;
+ WRITE_UTF16BE(z, i);
+ n = (int)(z-zBuf);
+ assert( n>0 && n<=4 );
+ z[0] = 0;
+ z = zBuf;
+ READ_UTF16BE(z, 1, c);
+ assert( c==i );
+ assert( (z-zBuf)==n );
+ }
+}
+#endif /* SQLITE_TEST */
+#endif /* SQLITE_OMIT_UTF16 */
+
+/************** End of utf.c *************************************************/
+/************** Begin file util.c ********************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Utility functions used throughout sqlite.
+**
+** This file contains functions for allocating memory, comparing
+** strings, and stuff like that.
+**
+*/
+/* #include "sqliteInt.h" */
+/* #include */
+#if HAVE_ISNAN || SQLITE_HAVE_ISNAN
+# include
+#endif
+
+/*
+** Routine needed to support the testcase() macro.
+*/
+#ifdef SQLITE_COVERAGE_TEST
+SQLITE_PRIVATE void sqlite3Coverage(int x){
+ static unsigned dummy = 0;
+ dummy += (unsigned)x;
+}
+#endif
+
+/*
+** Give a callback to the test harness that can be used to simulate faults
+** in places where it is difficult or expensive to do so purely by means
+** of inputs.
+**
+** The intent of the integer argument is to let the fault simulator know
+** which of multiple sqlite3FaultSim() calls has been hit.
+**
+** Return whatever integer value the test callback returns, or return
+** SQLITE_OK if no test callback is installed.
+*/
+#ifndef SQLITE_UNTESTABLE
+SQLITE_PRIVATE int sqlite3FaultSim(int iTest){
+ int (*xCallback)(int) = sqlite3GlobalConfig.xTestCallback;
+ return xCallback ? xCallback(iTest) : SQLITE_OK;
+}
+#endif
+
+#ifndef SQLITE_OMIT_FLOATING_POINT
+/*
+** Return true if the floating point value is Not a Number (NaN).
+**
+** Use the math library isnan() function if compiled with SQLITE_HAVE_ISNAN.
+** Otherwise, we have our own implementation that works on most systems.
+*/
+SQLITE_PRIVATE int sqlite3IsNaN(double x){
+ int rc; /* The value return */
+#if !SQLITE_HAVE_ISNAN && !HAVE_ISNAN
+ /*
+ ** Systems that support the isnan() library function should probably
+ ** make use of it by compiling with -DSQLITE_HAVE_ISNAN. But we have
+ ** found that many systems do not have a working isnan() function so
+ ** this implementation is provided as an alternative.
+ **
+ ** This NaN test sometimes fails if compiled on GCC with -ffast-math.
+ ** On the other hand, the use of -ffast-math comes with the following
+ ** warning:
+ **
+ ** This option [-ffast-math] should never be turned on by any
+ ** -O option since it can result in incorrect output for programs
+ ** which depend on an exact implementation of IEEE or ISO
+ ** rules/specifications for math functions.
+ **
+ ** Under MSVC, this NaN test may fail if compiled with a floating-
+ ** point precision mode other than /fp:precise. From the MSDN
+ ** documentation:
+ **
+ ** The compiler [with /fp:precise] will properly handle comparisons
+ ** involving NaN. For example, x != x evaluates to true if x is NaN
+ ** ...
+ */
+#ifdef __FAST_MATH__
+# error SQLite will not work correctly with the -ffast-math option of GCC.
+#endif
+ volatile double y = x;
+ volatile double z = y;
+ rc = (y!=z);
+#else /* if HAVE_ISNAN */
+ rc = isnan(x);
+#endif /* HAVE_ISNAN */
+ testcase( rc );
+ return rc;
+}
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+
+/*
+** Compute a string length that is limited to what can be stored in
+** lower 30 bits of a 32-bit signed integer.
+**
+** The value returned will never be negative. Nor will it ever be greater
+** than the actual length of the string. For very long strings (greater
+** than 1GiB) the value returned might be less than the true string length.
+*/
+SQLITE_PRIVATE int sqlite3Strlen30(const char *z){
+ if( z==0 ) return 0;
+ return 0x3fffffff & (int)strlen(z);
+}
+
+/*
+** Return the declared type of a column. Or return zDflt if the column
+** has no declared type.
+**
+** The column type is an extra string stored after the zero-terminator on
+** the column name if and only if the COLFLAG_HASTYPE flag is set.
+*/
+SQLITE_PRIVATE char *sqlite3ColumnType(Column *pCol, char *zDflt){
+ if( (pCol->colFlags & COLFLAG_HASTYPE)==0 ) return zDflt;
+ return pCol->zName + strlen(pCol->zName) + 1;
+}
+
+/*
+** Helper function for sqlite3Error() - called rarely. Broken out into
+** a separate routine to avoid unnecessary register saves on entry to
+** sqlite3Error().
+*/
+static SQLITE_NOINLINE void sqlite3ErrorFinish(sqlite3 *db, int err_code){
+ if( db->pErr ) sqlite3ValueSetNull(db->pErr);
+ sqlite3SystemError(db, err_code);
+}
+
+/*
+** Set the current error code to err_code and clear any prior error message.
+** Also set iSysErrno (by calling sqlite3System) if the err_code indicates
+** that would be appropriate.
+*/
+SQLITE_PRIVATE void sqlite3Error(sqlite3 *db, int err_code){
+ assert( db!=0 );
+ db->errCode = err_code;
+ if( err_code || db->pErr ) sqlite3ErrorFinish(db, err_code);
+}
+
+/*
+** Load the sqlite3.iSysErrno field if that is an appropriate thing
+** to do based on the SQLite error code in rc.
+*/
+SQLITE_PRIVATE void sqlite3SystemError(sqlite3 *db, int rc){
+ if( rc==SQLITE_IOERR_NOMEM ) return;
+ rc &= 0xff;
+ if( rc==SQLITE_CANTOPEN || rc==SQLITE_IOERR ){
+ db->iSysErrno = sqlite3OsGetLastError(db->pVfs);
+ }
+}
+
+/*
+** Set the most recent error code and error string for the sqlite
+** handle "db". The error code is set to "err_code".
+**
+** If it is not NULL, string zFormat specifies the format of the
+** error string in the style of the printf functions: The following
+** format characters are allowed:
+**
+** %s Insert a string
+** %z A string that should be freed after use
+** %d Insert an integer
+** %T Insert a token
+** %S Insert the first element of a SrcList
+**
+** zFormat and any string tokens that follow it are assumed to be
+** encoded in UTF-8.
+**
+** To clear the most recent error for sqlite handle "db", sqlite3Error
+** should be called with err_code set to SQLITE_OK and zFormat set
+** to NULL.
+*/
+SQLITE_PRIVATE void sqlite3ErrorWithMsg(sqlite3 *db, int err_code, const char *zFormat, ...){
+ assert( db!=0 );
+ db->errCode = err_code;
+ sqlite3SystemError(db, err_code);
+ if( zFormat==0 ){
+ sqlite3Error(db, err_code);
+ }else if( db->pErr || (db->pErr = sqlite3ValueNew(db))!=0 ){
+ char *z;
+ va_list ap;
+ va_start(ap, zFormat);
+ z = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);
+ }
+}
+
+/*
+** Add an error message to pParse->zErrMsg and increment pParse->nErr.
+** The following formatting characters are allowed:
+**
+** %s Insert a string
+** %z A string that should be freed after use
+** %d Insert an integer
+** %T Insert a token
+** %S Insert the first element of a SrcList
+**
+** This function should be used to report any error that occurs while
+** compiling an SQL statement (i.e. within sqlite3_prepare()). The
+** last thing the sqlite3_prepare() function does is copy the error
+** stored by this function into the database handle using sqlite3Error().
+** Functions sqlite3Error() or sqlite3ErrorWithMsg() should be used
+** during statement execution (sqlite3_step() etc.).
+*/
+SQLITE_PRIVATE void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
+ char *zMsg;
+ va_list ap;
+ sqlite3 *db = pParse->db;
+ va_start(ap, zFormat);
+ zMsg = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ if( db->suppressErr ){
+ sqlite3DbFree(db, zMsg);
+ }else{
+ pParse->nErr++;
+ sqlite3DbFree(db, pParse->zErrMsg);
+ pParse->zErrMsg = zMsg;
+ pParse->rc = SQLITE_ERROR;
+ }
+}
+
+/*
+** Convert an SQL-style quoted string into a normal string by removing
+** the quote characters. The conversion is done in-place. If the
+** input does not begin with a quote character, then this routine
+** is a no-op.
+**
+** The input string must be zero-terminated. A new zero-terminator
+** is added to the dequoted string.
+**
+** The return value is -1 if no dequoting occurs or the length of the
+** dequoted string, exclusive of the zero terminator, if dequoting does
+** occur.
+**
+** 2002-Feb-14: This routine is extended to remove MS-Access style
+** brackets from around identifiers. For example: "[a-b-c]" becomes
+** "a-b-c".
+*/
+SQLITE_PRIVATE void sqlite3Dequote(char *z){
+ char quote;
+ int i, j;
+ if( z==0 ) return;
+ quote = z[0];
+ if( !sqlite3Isquote(quote) ) return;
+ if( quote=='[' ) quote = ']';
+ for(i=1, j=0;; i++){
+ assert( z[i] );
+ if( z[i]==quote ){
+ if( z[i+1]==quote ){
+ z[j++] = quote;
+ i++;
+ }else{
+ break;
+ }
+ }else{
+ z[j++] = z[i];
+ }
+ }
+ z[j] = 0;
+}
+
+/*
+** Generate a Token object from a string
+*/
+SQLITE_PRIVATE void sqlite3TokenInit(Token *p, char *z){
+ p->z = z;
+ p->n = sqlite3Strlen30(z);
+}
+
+/* Convenient short-hand */
+#define UpperToLower sqlite3UpperToLower
+
+/*
+** Some systems have stricmp(). Others have strcasecmp(). Because
+** there is no consistency, we will define our own.
+**
+** IMPLEMENTATION-OF: R-30243-02494 The sqlite3_stricmp() and
+** sqlite3_strnicmp() APIs allow applications and extensions to compare
+** the contents of two buffers containing UTF-8 strings in a
+** case-independent fashion, using the same definition of "case
+** independence" that SQLite uses internally when comparing identifiers.
+*/
+SQLITE_API int sqlite3_stricmp(const char *zLeft, const char *zRight){
+ if( zLeft==0 ){
+ return zRight ? -1 : 0;
+ }else if( zRight==0 ){
+ return 1;
+ }
+ return sqlite3StrICmp(zLeft, zRight);
+}
+SQLITE_PRIVATE int sqlite3StrICmp(const char *zLeft, const char *zRight){
+ unsigned char *a, *b;
+ int c;
+ a = (unsigned char *)zLeft;
+ b = (unsigned char *)zRight;
+ for(;;){
+ c = (int)UpperToLower[*a] - (int)UpperToLower[*b];
+ if( c || *a==0 ) break;
+ a++;
+ b++;
+ }
+ return c;
+}
+SQLITE_API int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
+ register unsigned char *a, *b;
+ if( zLeft==0 ){
+ return zRight ? -1 : 0;
+ }else if( zRight==0 ){
+ return 1;
+ }
+ a = (unsigned char *)zLeft;
+ b = (unsigned char *)zRight;
+ while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
+ return N<0 ? 0 : UpperToLower[*a] - UpperToLower[*b];
+}
+
+/*
+** Compute 10 to the E-th power. Examples: E==1 results in 10.
+** E==2 results in 100. E==50 results in 1.0e50.
+**
+** This routine only works for values of E between 1 and 341.
+*/
+static LONGDOUBLE_TYPE sqlite3Pow10(int E){
+#if defined(_MSC_VER)
+ static const LONGDOUBLE_TYPE x[] = {
+ 1.0e+001,
+ 1.0e+002,
+ 1.0e+004,
+ 1.0e+008,
+ 1.0e+016,
+ 1.0e+032,
+ 1.0e+064,
+ 1.0e+128,
+ 1.0e+256
+ };
+ LONGDOUBLE_TYPE r = 1.0;
+ int i;
+ assert( E>=0 && E<=307 );
+ for(i=0; E!=0; i++, E >>=1){
+ if( E & 1 ) r *= x[i];
+ }
+ return r;
+#else
+ LONGDOUBLE_TYPE x = 10.0;
+ LONGDOUBLE_TYPE r = 1.0;
+ while(1){
+ if( E & 1 ) r *= x;
+ E >>= 1;
+ if( E==0 ) break;
+ x *= x;
+ }
+ return r;
+#endif
+}
+
+/*
+** The string z[] is an text representation of a real number.
+** Convert this string to a double and write it into *pResult.
+**
+** The string z[] is length bytes in length (bytes, not characters) and
+** uses the encoding enc. The string is not necessarily zero-terminated.
+**
+** Return TRUE if the result is a valid real number (or integer) and FALSE
+** if the string is empty or contains extraneous text. Valid numbers
+** are in one of these formats:
+**
+** [+-]digits[E[+-]digits]
+** [+-]digits.[digits][E[+-]digits]
+** [+-].digits[E[+-]digits]
+**
+** Leading and trailing whitespace is ignored for the purpose of determining
+** validity.
+**
+** If some prefix of the input string is a valid number, this routine
+** returns FALSE but it still converts the prefix and writes the result
+** into *pResult.
+*/
+SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult, int length, u8 enc){
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ int incr;
+ const char *zEnd = z + length;
+ /* sign * significand * (10 ^ (esign * exponent)) */
+ int sign = 1; /* sign of significand */
+ i64 s = 0; /* significand */
+ int d = 0; /* adjust exponent for shifting decimal point */
+ int esign = 1; /* sign of exponent */
+ int e = 0; /* exponent */
+ int eValid = 1; /* True exponent is either not used or is well-formed */
+ double result;
+ int nDigits = 0;
+ int nonNum = 0; /* True if input contains UTF16 with high byte non-zero */
+
+ assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+ *pResult = 0.0; /* Default return value, in case of an error */
+
+ if( enc==SQLITE_UTF8 ){
+ incr = 1;
+ }else{
+ int i;
+ incr = 2;
+ assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+ for(i=3-enc; i=zEnd ) return 0;
+
+ /* get sign of significand */
+ if( *z=='-' ){
+ sign = -1;
+ z+=incr;
+ }else if( *z=='+' ){
+ z+=incr;
+ }
+
+ /* copy max significant digits to significand */
+ while( z=zEnd ) goto do_atof_calc;
+
+ /* if decimal point is present */
+ if( *z=='.' ){
+ z+=incr;
+ /* copy digits from after decimal to significand
+ ** (decrease exponent by d to shift decimal right) */
+ while( z=zEnd ) goto do_atof_calc;
+
+ /* if exponent is present */
+ if( *z=='e' || *z=='E' ){
+ z+=incr;
+ eValid = 0;
+
+ /* This branch is needed to avoid a (harmless) buffer overread. The
+ ** special comment alerts the mutation tester that the correct answer
+ ** is obtained even if the branch is omitted */
+ if( z>=zEnd ) goto do_atof_calc; /*PREVENTS-HARMLESS-OVERREAD*/
+
+ /* get sign of exponent */
+ if( *z=='-' ){
+ esign = -1;
+ z+=incr;
+ }else if( *z=='+' ){
+ z+=incr;
+ }
+ /* copy digits to exponent */
+ while( z0 ){ /*OPTIMIZATION-IF-TRUE*/
+ if( esign>0 ){
+ if( s>=(LARGEST_INT64/10) ) break; /*OPTIMIZATION-IF-FALSE*/
+ s *= 10;
+ }else{
+ if( s%10!=0 ) break; /*OPTIMIZATION-IF-FALSE*/
+ s /= 10;
+ }
+ e--;
+ }
+
+ /* adjust the sign of significand */
+ s = sign<0 ? -s : s;
+
+ if( e==0 ){ /*OPTIMIZATION-IF-TRUE*/
+ result = (double)s;
+ }else{
+ /* attempt to handle extremely small/large numbers better */
+ if( e>307 ){ /*OPTIMIZATION-IF-TRUE*/
+ if( e<342 ){ /*OPTIMIZATION-IF-TRUE*/
+ LONGDOUBLE_TYPE scale = sqlite3Pow10(e-308);
+ if( esign<0 ){
+ result = s / scale;
+ result /= 1.0e+308;
+ }else{
+ result = s * scale;
+ result *= 1.0e+308;
+ }
+ }else{ assert( e>=342 );
+ if( esign<0 ){
+ result = 0.0*s;
+ }else{
+#ifdef INFINITY
+ result = INFINITY*s;
+#else
+ result = 1e308*1e308*s; /* Infinity */
+#endif
+ }
+ }
+ }else{
+ LONGDOUBLE_TYPE scale = sqlite3Pow10(e);
+ if( esign<0 ){
+ result = s / scale;
+ }else{
+ result = s * scale;
+ }
+ }
+ }
+ }
+
+ /* store the result */
+ *pResult = result;
+
+ /* return true if number and no extra non-whitespace chracters after */
+ return z==zEnd && nDigits>0 && eValid && nonNum==0;
+#else
+ return !sqlite3Atoi64(z, pResult, length, enc);
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+}
+
+/*
+** Compare the 19-character string zNum against the text representation
+** value 2^63: 9223372036854775808. Return negative, zero, or positive
+** if zNum is less than, equal to, or greater than the string.
+** Note that zNum must contain exactly 19 characters.
+**
+** Unlike memcmp() this routine is guaranteed to return the difference
+** in the values of the last digit if the only difference is in the
+** last digit. So, for example,
+**
+** compare2pow63("9223372036854775800", 1)
+**
+** will return -8.
+*/
+static int compare2pow63(const char *zNum, int incr){
+ int c = 0;
+ int i;
+ /* 012345678901234567 */
+ const char *pow63 = "922337203685477580";
+ for(i=0; c==0 && i<18; i++){
+ c = (zNum[i*incr]-pow63[i])*10;
+ }
+ if( c==0 ){
+ c = zNum[18*incr] - '8';
+ testcase( c==(-1) );
+ testcase( c==0 );
+ testcase( c==(+1) );
+ }
+ return c;
+}
+
+/*
+** Convert zNum to a 64-bit signed integer. zNum must be decimal. This
+** routine does *not* accept hexadecimal notation.
+**
+** Returns:
+**
+** 0 Successful transformation. Fits in a 64-bit signed integer.
+** 1 Excess non-space text after the integer value
+** 2 Integer too large for a 64-bit signed integer or is malformed
+** 3 Special case of 9223372036854775808
+**
+** length is the number of bytes in the string (bytes, not characters).
+** The string is not necessarily zero-terminated. The encoding is
+** given by enc.
+*/
+SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc){
+ int incr;
+ u64 u = 0;
+ int neg = 0; /* assume positive */
+ int i;
+ int c = 0;
+ int nonNum = 0; /* True if input contains UTF16 with high byte non-zero */
+ int rc; /* Baseline return code */
+ const char *zStart;
+ const char *zEnd = zNum + length;
+ assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+ if( enc==SQLITE_UTF8 ){
+ incr = 1;
+ }else{
+ incr = 2;
+ assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+ for(i=3-enc; i='0' && c<='9'; i+=incr){
+ u = u*10 + c - '0';
+ }
+ testcase( i==18*incr );
+ testcase( i==19*incr );
+ testcase( i==20*incr );
+ if( u>LARGEST_INT64 ){
+ /* This test and assignment is needed only to suppress UB warnings
+ ** from clang and -fsanitize=undefined. This test and assignment make
+ ** the code a little larger and slower, and no harm comes from omitting
+ ** them, but we must appaise the undefined-behavior pharisees. */
+ *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64;
+ }else if( neg ){
+ *pNum = -(i64)u;
+ }else{
+ *pNum = (i64)u;
+ }
+ rc = 0;
+ if( (i==0 && zStart==zNum) /* No digits */
+ || nonNum /* UTF16 with high-order bytes non-zero */
+ ){
+ rc = 1;
+ }else if( &zNum[i]19*incr ? 1 : compare2pow63(zNum, incr);
+ if( c<0 ){
+ /* zNum is less than 9223372036854775808 so it fits */
+ assert( u<=LARGEST_INT64 );
+ return rc;
+ }else{
+ *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64;
+ if( c>0 ){
+ /* zNum is greater than 9223372036854775808 so it overflows */
+ return 2;
+ }else{
+ /* zNum is exactly 9223372036854775808. Fits if negative. The
+ ** special case 2 overflow if positive */
+ assert( u-1==LARGEST_INT64 );
+ return neg ? rc : 3;
+ }
+ }
+ }
+}
+
+/*
+** Transform a UTF-8 integer literal, in either decimal or hexadecimal,
+** into a 64-bit signed integer. This routine accepts hexadecimal literals,
+** whereas sqlite3Atoi64() does not.
+**
+** Returns:
+**
+** 0 Successful transformation. Fits in a 64-bit signed integer.
+** 1 Excess text after the integer value
+** 2 Integer too large for a 64-bit signed integer or is malformed
+** 3 Special case of 9223372036854775808
+*/
+SQLITE_PRIVATE int sqlite3DecOrHexToI64(const char *z, i64 *pOut){
+#ifndef SQLITE_OMIT_HEX_INTEGER
+ if( z[0]=='0'
+ && (z[1]=='x' || z[1]=='X')
+ ){
+ u64 u = 0;
+ int i, k;
+ for(i=2; z[i]=='0'; i++){}
+ for(k=i; sqlite3Isxdigit(z[k]); k++){
+ u = u*16 + sqlite3HexToInt(z[k]);
+ }
+ memcpy(pOut, &u, 8);
+ return (z[k]==0 && k-i<=16) ? 0 : 2;
+ }else
+#endif /* SQLITE_OMIT_HEX_INTEGER */
+ {
+ return sqlite3Atoi64(z, pOut, sqlite3Strlen30(z), SQLITE_UTF8);
+ }
+}
+
+/*
+** If zNum represents an integer that will fit in 32-bits, then set
+** *pValue to that integer and return true. Otherwise return false.
+**
+** This routine accepts both decimal and hexadecimal notation for integers.
+**
+** Any non-numeric characters that following zNum are ignored.
+** This is different from sqlite3Atoi64() which requires the
+** input number to be zero-terminated.
+*/
+SQLITE_PRIVATE int sqlite3GetInt32(const char *zNum, int *pValue){
+ sqlite_int64 v = 0;
+ int i, c;
+ int neg = 0;
+ if( zNum[0]=='-' ){
+ neg = 1;
+ zNum++;
+ }else if( zNum[0]=='+' ){
+ zNum++;
+ }
+#ifndef SQLITE_OMIT_HEX_INTEGER
+ else if( zNum[0]=='0'
+ && (zNum[1]=='x' || zNum[1]=='X')
+ && sqlite3Isxdigit(zNum[2])
+ ){
+ u32 u = 0;
+ zNum += 2;
+ while( zNum[0]=='0' ) zNum++;
+ for(i=0; sqlite3Isxdigit(zNum[i]) && i<8; i++){
+ u = u*16 + sqlite3HexToInt(zNum[i]);
+ }
+ if( (u&0x80000000)==0 && sqlite3Isxdigit(zNum[i])==0 ){
+ memcpy(pValue, &u, 4);
+ return 1;
+ }else{
+ return 0;
+ }
+ }
+#endif
+ if( !sqlite3Isdigit(zNum[0]) ) return 0;
+ while( zNum[0]=='0' ) zNum++;
+ for(i=0; i<11 && (c = zNum[i] - '0')>=0 && c<=9; i++){
+ v = v*10 + c;
+ }
+
+ /* The longest decimal representation of a 32 bit integer is 10 digits:
+ **
+ ** 1234567890
+ ** 2^31 -> 2147483648
+ */
+ testcase( i==10 );
+ if( i>10 ){
+ return 0;
+ }
+ testcase( v-neg==2147483647 );
+ if( v-neg>2147483647 ){
+ return 0;
+ }
+ if( neg ){
+ v = -v;
+ }
+ *pValue = (int)v;
+ return 1;
+}
+
+/*
+** Return a 32-bit integer value extracted from a string. If the
+** string is not an integer, just return 0.
+*/
+SQLITE_PRIVATE int sqlite3Atoi(const char *z){
+ int x = 0;
+ if( z ) sqlite3GetInt32(z, &x);
+ return x;
+}
+
+/*
+** The variable-length integer encoding is as follows:
+**
+** KEY:
+** A = 0xxxxxxx 7 bits of data and one flag bit
+** B = 1xxxxxxx 7 bits of data and one flag bit
+** C = xxxxxxxx 8 bits of data
+**
+** 7 bits - A
+** 14 bits - BA
+** 21 bits - BBA
+** 28 bits - BBBA
+** 35 bits - BBBBA
+** 42 bits - BBBBBA
+** 49 bits - BBBBBBA
+** 56 bits - BBBBBBBA
+** 64 bits - BBBBBBBBC
+*/
+
+/*
+** Write a 64-bit variable-length integer to memory starting at p[0].
+** The length of data write will be between 1 and 9 bytes. The number
+** of bytes written is returned.
+**
+** A variable-length integer consists of the lower 7 bits of each byte
+** for all bytes that have the 8th bit set and one byte with the 8th
+** bit clear. Except, if we get to the 9th byte, it stores the full
+** 8 bits and is the last byte.
+*/
+static int SQLITE_NOINLINE putVarint64(unsigned char *p, u64 v){
+ int i, j, n;
+ u8 buf[10];
+ if( v & (((u64)0xff000000)<<32) ){
+ p[8] = (u8)v;
+ v >>= 8;
+ for(i=7; i>=0; i--){
+ p[i] = (u8)((v & 0x7f) | 0x80);
+ v >>= 7;
+ }
+ return 9;
+ }
+ n = 0;
+ do{
+ buf[n++] = (u8)((v & 0x7f) | 0x80);
+ v >>= 7;
+ }while( v!=0 );
+ buf[0] &= 0x7f;
+ assert( n<=9 );
+ for(i=0, j=n-1; j>=0; j--, i++){
+ p[i] = buf[j];
+ }
+ return n;
+}
+SQLITE_PRIVATE int sqlite3PutVarint(unsigned char *p, u64 v){
+ if( v<=0x7f ){
+ p[0] = v&0x7f;
+ return 1;
+ }
+ if( v<=0x3fff ){
+ p[0] = ((v>>7)&0x7f)|0x80;
+ p[1] = v&0x7f;
+ return 2;
+ }
+ return putVarint64(p,v);
+}
+
+/*
+** Bitmasks used by sqlite3GetVarint(). These precomputed constants
+** are defined here rather than simply putting the constant expressions
+** inline in order to work around bugs in the RVT compiler.
+**
+** SLOT_2_0 A mask for (0x7f<<14) | 0x7f
+**
+** SLOT_4_2_0 A mask for (0x7f<<28) | SLOT_2_0
+*/
+#define SLOT_2_0 0x001fc07f
+#define SLOT_4_2_0 0xf01fc07f
+
+
+/*
+** Read a 64-bit variable-length integer from memory starting at p[0].
+** Return the number of bytes read. The value is stored in *v.
+*/
+SQLITE_PRIVATE u8 sqlite3GetVarint(const unsigned char *p, u64 *v){
+ u32 a,b,s;
+
+ a = *p;
+ /* a: p0 (unmasked) */
+ if (!(a&0x80))
+ {
+ *v = a;
+ return 1;
+ }
+
+ p++;
+ b = *p;
+ /* b: p1 (unmasked) */
+ if (!(b&0x80))
+ {
+ a &= 0x7f;
+ a = a<<7;
+ a |= b;
+ *v = a;
+ return 2;
+ }
+
+ /* Verify that constants are precomputed correctly */
+ assert( SLOT_2_0 == ((0x7f<<14) | (0x7f)) );
+ assert( SLOT_4_2_0 == ((0xfU<<28) | (0x7f<<14) | (0x7f)) );
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<14 | p2 (unmasked) */
+ if (!(a&0x80))
+ {
+ a &= SLOT_2_0;
+ b &= 0x7f;
+ b = b<<7;
+ a |= b;
+ *v = a;
+ return 3;
+ }
+
+ /* CSE1 from below */
+ a &= SLOT_2_0;
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<14 | p3 (unmasked) */
+ if (!(b&0x80))
+ {
+ b &= SLOT_2_0;
+ /* moved CSE1 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ a = a<<7;
+ a |= b;
+ *v = a;
+ return 4;
+ }
+
+ /* a: p0<<14 | p2 (masked) */
+ /* b: p1<<14 | p3 (unmasked) */
+ /* 1:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+ /* moved CSE1 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ b &= SLOT_2_0;
+ s = a;
+ /* s: p0<<14 | p2 (masked) */
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<28 | p2<<14 | p4 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* we can skip these cause they were (effectively) done above
+ ** while calculating s */
+ /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+ /* b &= (0x7f<<14)|(0x7f); */
+ b = b<<7;
+ a |= b;
+ s = s>>18;
+ *v = ((u64)s)<<32 | a;
+ return 5;
+ }
+
+ /* 2:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+ s = s<<7;
+ s |= b;
+ /* s: p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<28 | p3<<14 | p5 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* we can skip this cause it was (effectively) done above in calc'ing s */
+ /* b &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+ a &= SLOT_2_0;
+ a = a<<7;
+ a |= b;
+ s = s>>18;
+ *v = ((u64)s)<<32 | a;
+ return 6;
+ }
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p2<<28 | p4<<14 | p6 (unmasked) */
+ if (!(a&0x80))
+ {
+ a &= SLOT_4_2_0;
+ b &= SLOT_2_0;
+ b = b<<7;
+ a |= b;
+ s = s>>11;
+ *v = ((u64)s)<<32 | a;
+ return 7;
+ }
+
+ /* CSE2 from below */
+ a &= SLOT_2_0;
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p3<<28 | p5<<14 | p7 (unmasked) */
+ if (!(b&0x80))
+ {
+ b &= SLOT_4_2_0;
+ /* moved CSE2 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ a = a<<7;
+ a |= b;
+ s = s>>4;
+ *v = ((u64)s)<<32 | a;
+ return 8;
+ }
+
+ p++;
+ a = a<<15;
+ a |= *p;
+ /* a: p4<<29 | p6<<15 | p8 (unmasked) */
+
+ /* moved CSE2 up */
+ /* a &= (0x7f<<29)|(0x7f<<15)|(0xff); */
+ b &= SLOT_2_0;
+ b = b<<8;
+ a |= b;
+
+ s = s<<4;
+ b = p[-4];
+ b &= 0x7f;
+ b = b>>3;
+ s |= b;
+
+ *v = ((u64)s)<<32 | a;
+
+ return 9;
+}
+
+/*
+** Read a 32-bit variable-length integer from memory starting at p[0].
+** Return the number of bytes read. The value is stored in *v.
+**
+** If the varint stored in p[0] is larger than can fit in a 32-bit unsigned
+** integer, then set *v to 0xffffffff.
+**
+** A MACRO version, getVarint32, is provided which inlines the
+** single-byte case. All code should use the MACRO version as
+** this function assumes the single-byte case has already been handled.
+*/
+SQLITE_PRIVATE u8 sqlite3GetVarint32(const unsigned char *p, u32 *v){
+ u32 a,b;
+
+ /* The 1-byte case. Overwhelmingly the most common. Handled inline
+ ** by the getVarin32() macro */
+ a = *p;
+ /* a: p0 (unmasked) */
+#ifndef getVarint32
+ if (!(a&0x80))
+ {
+ /* Values between 0 and 127 */
+ *v = a;
+ return 1;
+ }
+#endif
+
+ /* The 2-byte case */
+ p++;
+ b = *p;
+ /* b: p1 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* Values between 128 and 16383 */
+ a &= 0x7f;
+ a = a<<7;
+ *v = a | b;
+ return 2;
+ }
+
+ /* The 3-byte case */
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<14 | p2 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* Values between 16384 and 2097151 */
+ a &= (0x7f<<14)|(0x7f);
+ b &= 0x7f;
+ b = b<<7;
+ *v = a | b;
+ return 3;
+ }
+
+ /* A 32-bit varint is used to store size information in btrees.
+ ** Objects are rarely larger than 2MiB limit of a 3-byte varint.
+ ** A 3-byte varint is sufficient, for example, to record the size
+ ** of a 1048569-byte BLOB or string.
+ **
+ ** We only unroll the first 1-, 2-, and 3- byte cases. The very
+ ** rare larger cases can be handled by the slower 64-bit varint
+ ** routine.
+ */
+#if 1
+ {
+ u64 v64;
+ u8 n;
+
+ p -= 2;
+ n = sqlite3GetVarint(p, &v64);
+ assert( n>3 && n<=9 );
+ if( (v64 & SQLITE_MAX_U32)!=v64 ){
+ *v = 0xffffffff;
+ }else{
+ *v = (u32)v64;
+ }
+ return n;
+ }
+
+#else
+ /* For following code (kept for historical record only) shows an
+ ** unrolling for the 3- and 4-byte varint cases. This code is
+ ** slightly faster, but it is also larger and much harder to test.
+ */
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<14 | p3 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* Values between 2097152 and 268435455 */
+ b &= (0x7f<<14)|(0x7f);
+ a &= (0x7f<<14)|(0x7f);
+ a = a<<7;
+ *v = a | b;
+ return 4;
+ }
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<28 | p2<<14 | p4 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* Values between 268435456 and 34359738367 */
+ a &= SLOT_4_2_0;
+ b &= SLOT_4_2_0;
+ b = b<<7;
+ *v = a | b;
+ return 5;
+ }
+
+ /* We can only reach this point when reading a corrupt database
+ ** file. In that case we are not in any hurry. Use the (relatively
+ ** slow) general-purpose sqlite3GetVarint() routine to extract the
+ ** value. */
+ {
+ u64 v64;
+ u8 n;
+
+ p -= 4;
+ n = sqlite3GetVarint(p, &v64);
+ assert( n>5 && n<=9 );
+ *v = (u32)v64;
+ return n;
+ }
+#endif
+}
+
+/*
+** Return the number of bytes that will be needed to store the given
+** 64-bit integer.
+*/
+SQLITE_PRIVATE int sqlite3VarintLen(u64 v){
+ int i;
+ for(i=1; (v >>= 7)!=0; i++){ assert( i<10 ); }
+ return i;
+}
+
+
+/*
+** Read or write a four-byte big-endian integer value.
+*/
+SQLITE_PRIVATE u32 sqlite3Get4byte(const u8 *p){
+#if SQLITE_BYTEORDER==4321
+ u32 x;
+ memcpy(&x,p,4);
+ return x;
+#elif SQLITE_BYTEORDER==1234 && GCC_VERSION>=4003000
+ u32 x;
+ memcpy(&x,p,4);
+ return __builtin_bswap32(x);
+#elif SQLITE_BYTEORDER==1234 && MSVC_VERSION>=1300
+ u32 x;
+ memcpy(&x,p,4);
+ return _byteswap_ulong(x);
+#else
+ testcase( p[0]&0x80 );
+ return ((unsigned)p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
+#endif
+}
+SQLITE_PRIVATE void sqlite3Put4byte(unsigned char *p, u32 v){
+#if SQLITE_BYTEORDER==4321
+ memcpy(p,&v,4);
+#elif SQLITE_BYTEORDER==1234 && GCC_VERSION>=4003000
+ u32 x = __builtin_bswap32(v);
+ memcpy(p,&x,4);
+#elif SQLITE_BYTEORDER==1234 && MSVC_VERSION>=1300
+ u32 x = _byteswap_ulong(v);
+ memcpy(p,&x,4);
+#else
+ p[0] = (u8)(v>>24);
+ p[1] = (u8)(v>>16);
+ p[2] = (u8)(v>>8);
+ p[3] = (u8)v;
+#endif
+}
+
+
+
+/*
+** Translate a single byte of Hex into an integer.
+** This routine only works if h really is a valid hexadecimal
+** character: 0..9a..fA..F
+*/
+SQLITE_PRIVATE u8 sqlite3HexToInt(int h){
+ assert( (h>='0' && h<='9') || (h>='a' && h<='f') || (h>='A' && h<='F') );
+#ifdef SQLITE_ASCII
+ h += 9*(1&(h>>6));
+#endif
+#ifdef SQLITE_EBCDIC
+ h += 9*(1&~(h>>4));
+#endif
+ return (u8)(h & 0xf);
+}
+
+#if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC)
+/*
+** Convert a BLOB literal of the form "x'hhhhhh'" into its binary
+** value. Return a pointer to its binary value. Space to hold the
+** binary value has been obtained from malloc and must be freed by
+** the calling routine.
+*/
+SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3 *db, const char *z, int n){
+ char *zBlob;
+ int i;
+
+ zBlob = (char *)sqlite3DbMallocRawNN(db, n/2 + 1);
+ n--;
+ if( zBlob ){
+ for(i=0; imagic;
+ if( magic!=SQLITE_MAGIC_OPEN ){
+ if( sqlite3SafetyCheckSickOrOk(db) ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ logBadConnection("unopened");
+ }
+ return 0;
+ }else{
+ return 1;
+ }
+}
+SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3 *db){
+ u32 magic;
+ magic = db->magic;
+ if( magic!=SQLITE_MAGIC_SICK &&
+ magic!=SQLITE_MAGIC_OPEN &&
+ magic!=SQLITE_MAGIC_BUSY ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ logBadConnection("invalid");
+ return 0;
+ }else{
+ return 1;
+ }
+}
+
+/*
+** Attempt to add, substract, or multiply the 64-bit signed value iB against
+** the other 64-bit signed integer at *pA and store the result in *pA.
+** Return 0 on success. Or if the operation would have resulted in an
+** overflow, leave *pA unchanged and return 1.
+*/
+SQLITE_PRIVATE int sqlite3AddInt64(i64 *pA, i64 iB){
+#if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER)
+ return __builtin_add_overflow(*pA, iB, pA);
+#else
+ i64 iA = *pA;
+ testcase( iA==0 ); testcase( iA==1 );
+ testcase( iB==-1 ); testcase( iB==0 );
+ if( iB>=0 ){
+ testcase( iA>0 && LARGEST_INT64 - iA == iB );
+ testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 );
+ if( iA>0 && LARGEST_INT64 - iA < iB ) return 1;
+ }else{
+ testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 );
+ testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 );
+ if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1;
+ }
+ *pA += iB;
+ return 0;
+#endif
+}
+SQLITE_PRIVATE int sqlite3SubInt64(i64 *pA, i64 iB){
+#if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER)
+ return __builtin_sub_overflow(*pA, iB, pA);
+#else
+ testcase( iB==SMALLEST_INT64+1 );
+ if( iB==SMALLEST_INT64 ){
+ testcase( (*pA)==(-1) ); testcase( (*pA)==0 );
+ if( (*pA)>=0 ) return 1;
+ *pA -= iB;
+ return 0;
+ }else{
+ return sqlite3AddInt64(pA, -iB);
+ }
+#endif
+}
+SQLITE_PRIVATE int sqlite3MulInt64(i64 *pA, i64 iB){
+#if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER)
+ return __builtin_mul_overflow(*pA, iB, pA);
+#else
+ i64 iA = *pA;
+ if( iB>0 ){
+ if( iA>LARGEST_INT64/iB ) return 1;
+ if( iA0 ){
+ if( iBLARGEST_INT64/-iB ) return 1;
+ }
+ }
+ *pA = iA*iB;
+ return 0;
+#endif
+}
+
+/*
+** Compute the absolute value of a 32-bit signed integer, of possible. Or
+** if the integer has a value of -2147483648, return +2147483647
+*/
+SQLITE_PRIVATE int sqlite3AbsInt32(int x){
+ if( x>=0 ) return x;
+ if( x==(int)0x80000000 ) return 0x7fffffff;
+ return -x;
+}
+
+#ifdef SQLITE_ENABLE_8_3_NAMES
+/*
+** If SQLITE_ENABLE_8_3_NAMES is set at compile-time and if the database
+** filename in zBaseFilename is a URI with the "8_3_names=1" parameter and
+** if filename in z[] has a suffix (a.k.a. "extension") that is longer than
+** three characters, then shorten the suffix on z[] to be the last three
+** characters of the original suffix.
+**
+** If SQLITE_ENABLE_8_3_NAMES is set to 2 at compile-time, then always
+** do the suffix shortening regardless of URI parameter.
+**
+** Examples:
+**
+** test.db-journal => test.nal
+** test.db-wal => test.wal
+** test.db-shm => test.shm
+** test.db-mj7f3319fa => test.9fa
+*/
+SQLITE_PRIVATE void sqlite3FileSuffix3(const char *zBaseFilename, char *z){
+#if SQLITE_ENABLE_8_3_NAMES<2
+ if( sqlite3_uri_boolean(zBaseFilename, "8_3_names", 0) )
+#endif
+ {
+ int i, sz;
+ sz = sqlite3Strlen30(z);
+ for(i=sz-1; i>0 && z[i]!='/' && z[i]!='.'; i--){}
+ if( z[i]=='.' && ALWAYS(sz>i+4) ) memmove(&z[i+1], &z[sz-3], 4);
+ }
+}
+#endif
+
+/*
+** Find (an approximate) sum of two LogEst values. This computation is
+** not a simple "+" operator because LogEst is stored as a logarithmic
+** value.
+**
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst a, LogEst b){
+ static const unsigned char x[] = {
+ 10, 10, /* 0,1 */
+ 9, 9, /* 2,3 */
+ 8, 8, /* 4,5 */
+ 7, 7, 7, /* 6,7,8 */
+ 6, 6, 6, /* 9,10,11 */
+ 5, 5, 5, /* 12-14 */
+ 4, 4, 4, 4, /* 15-18 */
+ 3, 3, 3, 3, 3, 3, /* 19-24 */
+ 2, 2, 2, 2, 2, 2, 2, /* 25-31 */
+ };
+ if( a>=b ){
+ if( a>b+49 ) return a;
+ if( a>b+31 ) return a+1;
+ return a+x[a-b];
+ }else{
+ if( b>a+49 ) return b;
+ if( b>a+31 ) return b+1;
+ return b+x[b-a];
+ }
+}
+
+/*
+** Convert an integer into a LogEst. In other words, compute an
+** approximation for 10*log2(x).
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEst(u64 x){
+ static LogEst a[] = { 0, 2, 3, 5, 6, 7, 8, 9 };
+ LogEst y = 40;
+ if( x<8 ){
+ if( x<2 ) return 0;
+ while( x<8 ){ y -= 10; x <<= 1; }
+ }else{
+#if GCC_VERSION>=5004000
+ int i = 60 - __builtin_clzll(x);
+ y += i*10;
+ x >>= i;
+#else
+ while( x>255 ){ y += 40; x >>= 4; } /*OPTIMIZATION-IF-TRUE*/
+ while( x>15 ){ y += 10; x >>= 1; }
+#endif
+ }
+ return a[x&7] + y - 10;
+}
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/*
+** Convert a double into a LogEst
+** In other words, compute an approximation for 10*log2(x).
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double x){
+ u64 a;
+ LogEst e;
+ assert( sizeof(x)==8 && sizeof(a)==8 );
+ if( x<=1 ) return 0;
+ if( x<=2000000000 ) return sqlite3LogEst((u64)x);
+ memcpy(&a, &x, 8);
+ e = (a>>52) - 1022;
+ return e*10;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+
+#if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \
+ defined(SQLITE_ENABLE_STAT3_OR_STAT4) || \
+ defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
+/*
+** Convert a LogEst into an integer.
+**
+** Note that this routine is only used when one or more of various
+** non-standard compile-time options is enabled.
+*/
+SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst x){
+ u64 n;
+ n = x%10;
+ x /= 10;
+ if( n>=5 ) n -= 2;
+ else if( n>=1 ) n -= 1;
+#if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \
+ defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
+ if( x>60 ) return (u64)LARGEST_INT64;
+#else
+ /* If only SQLITE_ENABLE_STAT3_OR_STAT4 is on, then the largest input
+ ** possible to this routine is 310, resulting in a maximum x of 31 */
+ assert( x<=60 );
+#endif
+ return x>=3 ? (n+8)<<(x-3) : (n+8)>>(3-x);
+}
+#endif /* defined SCANSTAT or STAT4 or ESTIMATED_ROWS */
+
+/*
+** Add a new name/number pair to a VList. This might require that the
+** VList object be reallocated, so return the new VList. If an OOM
+** error occurs, the original VList returned and the
+** db->mallocFailed flag is set.
+**
+** A VList is really just an array of integers. To destroy a VList,
+** simply pass it to sqlite3DbFree().
+**
+** The first integer is the number of integers allocated for the whole
+** VList. The second integer is the number of integers actually used.
+** Each name/number pair is encoded by subsequent groups of 3 or more
+** integers.
+**
+** Each name/number pair starts with two integers which are the numeric
+** value for the pair and the size of the name/number pair, respectively.
+** The text name overlays one or more following integers. The text name
+** is always zero-terminated.
+**
+** Conceptually:
+**
+** struct VList {
+** int nAlloc; // Number of allocated slots
+** int nUsed; // Number of used slots
+** struct VListEntry {
+** int iValue; // Value for this entry
+** int nSlot; // Slots used by this entry
+** // ... variable name goes here
+** } a[0];
+** }
+**
+** During code generation, pointers to the variable names within the
+** VList are taken. When that happens, nAlloc is set to zero as an
+** indication that the VList may never again be enlarged, since the
+** accompanying realloc() would invalidate the pointers.
+*/
+SQLITE_PRIVATE VList *sqlite3VListAdd(
+ sqlite3 *db, /* The database connection used for malloc() */
+ VList *pIn, /* The input VList. Might be NULL */
+ const char *zName, /* Name of symbol to add */
+ int nName, /* Bytes of text in zName */
+ int iVal /* Value to associate with zName */
+){
+ int nInt; /* number of sizeof(int) objects needed for zName */
+ char *z; /* Pointer to where zName will be stored */
+ int i; /* Index in pIn[] where zName is stored */
+
+ nInt = nName/4 + 3;
+ assert( pIn==0 || pIn[0]>=3 ); /* Verify ok to add new elements */
+ if( pIn==0 || pIn[1]+nInt > pIn[0] ){
+ /* Enlarge the allocation */
+ int nAlloc = (pIn ? pIn[0]*2 : 10) + nInt;
+ VList *pOut = sqlite3DbRealloc(db, pIn, nAlloc*sizeof(int));
+ if( pOut==0 ) return pIn;
+ if( pIn==0 ) pOut[1] = 2;
+ pIn = pOut;
+ pIn[0] = nAlloc;
+ }
+ i = pIn[1];
+ pIn[i] = iVal;
+ pIn[i+1] = nInt;
+ z = (char*)&pIn[i+2];
+ pIn[1] = i+nInt;
+ assert( pIn[1]<=pIn[0] );
+ memcpy(z, zName, nName);
+ z[nName] = 0;
+ return pIn;
+}
+
+/*
+** Return a pointer to the name of a variable in the given VList that
+** has the value iVal. Or return a NULL if there is no such variable in
+** the list
+*/
+SQLITE_PRIVATE const char *sqlite3VListNumToName(VList *pIn, int iVal){
+ int i, mx;
+ if( pIn==0 ) return 0;
+ mx = pIn[1];
+ i = 2;
+ do{
+ if( pIn[i]==iVal ) return (char*)&pIn[i+2];
+ i += pIn[i+1];
+ }while( i */
+
+/* Turn bulk memory into a hash table object by initializing the
+** fields of the Hash structure.
+**
+** "pNew" is a pointer to the hash table that is to be initialized.
+*/
+SQLITE_PRIVATE void sqlite3HashInit(Hash *pNew){
+ assert( pNew!=0 );
+ pNew->first = 0;
+ pNew->count = 0;
+ pNew->htsize = 0;
+ pNew->ht = 0;
+}
+
+/* Remove all entries from a hash table. Reclaim all memory.
+** Call this routine to delete a hash table or to reset a hash table
+** to the empty state.
+*/
+SQLITE_PRIVATE void sqlite3HashClear(Hash *pH){
+ HashElem *elem; /* For looping over all elements of the table */
+
+ assert( pH!=0 );
+ elem = pH->first;
+ pH->first = 0;
+ sqlite3_free(pH->ht);
+ pH->ht = 0;
+ pH->htsize = 0;
+ while( elem ){
+ HashElem *next_elem = elem->next;
+ sqlite3_free(elem);
+ elem = next_elem;
+ }
+ pH->count = 0;
+}
+
+/*
+** The hashing function.
+*/
+static unsigned int strHash(const char *z){
+ unsigned int h = 0;
+ unsigned char c;
+ while( (c = (unsigned char)*z++)!=0 ){ /*OPTIMIZATION-IF-TRUE*/
+ /* Knuth multiplicative hashing. (Sorting & Searching, p. 510).
+ ** 0x9e3779b1 is 2654435761 which is the closest prime number to
+ ** (2**32)*golden_ratio, where golden_ratio = (sqrt(5) - 1)/2. */
+ h += sqlite3UpperToLower[c];
+ h *= 0x9e3779b1;
+ }
+ return h;
+}
+
+
+/* Link pNew element into the hash table pH. If pEntry!=0 then also
+** insert pNew into the pEntry hash bucket.
+*/
+static void insertElement(
+ Hash *pH, /* The complete hash table */
+ struct _ht *pEntry, /* The entry into which pNew is inserted */
+ HashElem *pNew /* The element to be inserted */
+){
+ HashElem *pHead; /* First element already in pEntry */
+ if( pEntry ){
+ pHead = pEntry->count ? pEntry->chain : 0;
+ pEntry->count++;
+ pEntry->chain = pNew;
+ }else{
+ pHead = 0;
+ }
+ if( pHead ){
+ pNew->next = pHead;
+ pNew->prev = pHead->prev;
+ if( pHead->prev ){ pHead->prev->next = pNew; }
+ else { pH->first = pNew; }
+ pHead->prev = pNew;
+ }else{
+ pNew->next = pH->first;
+ if( pH->first ){ pH->first->prev = pNew; }
+ pNew->prev = 0;
+ pH->first = pNew;
+ }
+}
+
+
+/* Resize the hash table so that it cantains "new_size" buckets.
+**
+** The hash table might fail to resize if sqlite3_malloc() fails or
+** if the new size is the same as the prior size.
+** Return TRUE if the resize occurs and false if not.
+*/
+static int rehash(Hash *pH, unsigned int new_size){
+ struct _ht *new_ht; /* The new hash table */
+ HashElem *elem, *next_elem; /* For looping over existing elements */
+
+#if SQLITE_MALLOC_SOFT_LIMIT>0
+ if( new_size*sizeof(struct _ht)>SQLITE_MALLOC_SOFT_LIMIT ){
+ new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
+ }
+ if( new_size==pH->htsize ) return 0;
+#endif
+
+ /* The inability to allocates space for a larger hash table is
+ ** a performance hit but it is not a fatal error. So mark the
+ ** allocation as a benign. Use sqlite3Malloc()/memset(0) instead of
+ ** sqlite3MallocZero() to make the allocation, as sqlite3MallocZero()
+ ** only zeroes the requested number of bytes whereas this module will
+ ** use the actual amount of space allocated for the hash table (which
+ ** may be larger than the requested amount).
+ */
+ sqlite3BeginBenignMalloc();
+ new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
+ sqlite3EndBenignMalloc();
+
+ if( new_ht==0 ) return 0;
+ sqlite3_free(pH->ht);
+ pH->ht = new_ht;
+ pH->htsize = new_size = sqlite3MallocSize(new_ht)/sizeof(struct _ht);
+ memset(new_ht, 0, new_size*sizeof(struct _ht));
+ for(elem=pH->first, pH->first=0; elem; elem = next_elem){
+ unsigned int h = strHash(elem->pKey) % new_size;
+ next_elem = elem->next;
+ insertElement(pH, &new_ht[h], elem);
+ }
+ return 1;
+}
+
+/* This function (for internal use only) locates an element in an
+** hash table that matches the given key. If no element is found,
+** a pointer to a static null element with HashElem.data==0 is returned.
+** If pH is not NULL, then the hash for this key is written to *pH.
+*/
+static HashElem *findElementWithHash(
+ const Hash *pH, /* The pH to be searched */
+ const char *pKey, /* The key we are searching for */
+ unsigned int *pHash /* Write the hash value here */
+){
+ HashElem *elem; /* Used to loop thru the element list */
+ int count; /* Number of elements left to test */
+ unsigned int h; /* The computed hash */
+ static HashElem nullElement = { 0, 0, 0, 0 };
+
+ if( pH->ht ){ /*OPTIMIZATION-IF-TRUE*/
+ struct _ht *pEntry;
+ h = strHash(pKey) % pH->htsize;
+ pEntry = &pH->ht[h];
+ elem = pEntry->chain;
+ count = pEntry->count;
+ }else{
+ h = 0;
+ elem = pH->first;
+ count = pH->count;
+ }
+ if( pHash ) *pHash = h;
+ while( count-- ){
+ assert( elem!=0 );
+ if( sqlite3StrICmp(elem->pKey,pKey)==0 ){
+ return elem;
+ }
+ elem = elem->next;
+ }
+ return &nullElement;
+}
+
+/* Remove a single entry from the hash table given a pointer to that
+** element and a hash on the element's key.
+*/
+static void removeElementGivenHash(
+ Hash *pH, /* The pH containing "elem" */
+ HashElem* elem, /* The element to be removed from the pH */
+ unsigned int h /* Hash value for the element */
+){
+ struct _ht *pEntry;
+ if( elem->prev ){
+ elem->prev->next = elem->next;
+ }else{
+ pH->first = elem->next;
+ }
+ if( elem->next ){
+ elem->next->prev = elem->prev;
+ }
+ if( pH->ht ){
+ pEntry = &pH->ht[h];
+ if( pEntry->chain==elem ){
+ pEntry->chain = elem->next;
+ }
+ pEntry->count--;
+ assert( pEntry->count>=0 );
+ }
+ sqlite3_free( elem );
+ pH->count--;
+ if( pH->count==0 ){
+ assert( pH->first==0 );
+ assert( pH->count==0 );
+ sqlite3HashClear(pH);
+ }
+}
+
+/* Attempt to locate an element of the hash table pH with a key
+** that matches pKey. Return the data for this element if it is
+** found, or NULL if there is no match.
+*/
+SQLITE_PRIVATE void *sqlite3HashFind(const Hash *pH, const char *pKey){
+ assert( pH!=0 );
+ assert( pKey!=0 );
+ return findElementWithHash(pH, pKey, 0)->data;
+}
+
+/* Insert an element into the hash table pH. The key is pKey
+** and the data is "data".
+**
+** If no element exists with a matching key, then a new
+** element is created and NULL is returned.
+**
+** If another element already exists with the same key, then the
+** new data replaces the old data and the old data is returned.
+** The key is not copied in this instance. If a malloc fails, then
+** the new data is returned and the hash table is unchanged.
+**
+** If the "data" parameter to this function is NULL, then the
+** element corresponding to "key" is removed from the hash table.
+*/
+SQLITE_PRIVATE void *sqlite3HashInsert(Hash *pH, const char *pKey, void *data){
+ unsigned int h; /* the hash of the key modulo hash table size */
+ HashElem *elem; /* Used to loop thru the element list */
+ HashElem *new_elem; /* New element added to the pH */
+
+ assert( pH!=0 );
+ assert( pKey!=0 );
+ elem = findElementWithHash(pH,pKey,&h);
+ if( elem->data ){
+ void *old_data = elem->data;
+ if( data==0 ){
+ removeElementGivenHash(pH,elem,h);
+ }else{
+ elem->data = data;
+ elem->pKey = pKey;
+ }
+ return old_data;
+ }
+ if( data==0 ) return 0;
+ new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) );
+ if( new_elem==0 ) return data;
+ new_elem->pKey = pKey;
+ new_elem->data = data;
+ pH->count++;
+ if( pH->count>=10 && pH->count > 2*pH->htsize ){
+ if( rehash(pH, pH->count*2) ){
+ assert( pH->htsize>0 );
+ h = strHash(pKey) % pH->htsize;
+ }
+ }
+ insertElement(pH, pH->ht ? &pH->ht[h] : 0, new_elem);
+ return 0;
+}
+
+/************** End of hash.c ************************************************/
+/************** Begin file opcodes.c *****************************************/
+/* Automatically generated. Do not edit */
+/* See the tool/mkopcodec.tcl script for details. */
+#if !defined(SQLITE_OMIT_EXPLAIN) \
+ || defined(VDBE_PROFILE) \
+ || defined(SQLITE_DEBUG)
+#if defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) || defined(SQLITE_DEBUG)
+# define OpHelp(X) "\0" X
+#else
+# define OpHelp(X)
+#endif
+SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
+ static const char *const azName[] = {
+ /* 0 */ "Savepoint" OpHelp(""),
+ /* 1 */ "AutoCommit" OpHelp(""),
+ /* 2 */ "Transaction" OpHelp(""),
+ /* 3 */ "SorterNext" OpHelp(""),
+ /* 4 */ "Prev" OpHelp(""),
+ /* 5 */ "Next" OpHelp(""),
+ /* 6 */ "Checkpoint" OpHelp(""),
+ /* 7 */ "JournalMode" OpHelp(""),
+ /* 8 */ "Vacuum" OpHelp(""),
+ /* 9 */ "VFilter" OpHelp("iplan=r[P3] zplan='P4'"),
+ /* 10 */ "VUpdate" OpHelp("data=r[P3@P2]"),
+ /* 11 */ "Goto" OpHelp(""),
+ /* 12 */ "Gosub" OpHelp(""),
+ /* 13 */ "InitCoroutine" OpHelp(""),
+ /* 14 */ "Yield" OpHelp(""),
+ /* 15 */ "MustBeInt" OpHelp(""),
+ /* 16 */ "Jump" OpHelp(""),
+ /* 17 */ "Once" OpHelp(""),
+ /* 18 */ "If" OpHelp(""),
+ /* 19 */ "Not" OpHelp("r[P2]= !r[P1]"),
+ /* 20 */ "IfNot" OpHelp(""),
+ /* 21 */ "IfNullRow" OpHelp("if P1.nullRow then r[P3]=NULL, goto P2"),
+ /* 22 */ "SeekLT" OpHelp("key=r[P3@P4]"),
+ /* 23 */ "SeekLE" OpHelp("key=r[P3@P4]"),
+ /* 24 */ "SeekGE" OpHelp("key=r[P3@P4]"),
+ /* 25 */ "SeekGT" OpHelp("key=r[P3@P4]"),
+ /* 26 */ "IfNoHope" OpHelp("key=r[P3@P4]"),
+ /* 27 */ "NoConflict" OpHelp("key=r[P3@P4]"),
+ /* 28 */ "NotFound" OpHelp("key=r[P3@P4]"),
+ /* 29 */ "Found" OpHelp("key=r[P3@P4]"),
+ /* 30 */ "SeekRowid" OpHelp("intkey=r[P3]"),
+ /* 31 */ "NotExists" OpHelp("intkey=r[P3]"),
+ /* 32 */ "Last" OpHelp(""),
+ /* 33 */ "IfSmaller" OpHelp(""),
+ /* 34 */ "SorterSort" OpHelp(""),
+ /* 35 */ "Sort" OpHelp(""),
+ /* 36 */ "Rewind" OpHelp(""),
+ /* 37 */ "IdxLE" OpHelp("key=r[P3@P4]"),
+ /* 38 */ "IdxGT" OpHelp("key=r[P3@P4]"),
+ /* 39 */ "IdxLT" OpHelp("key=r[P3@P4]"),
+ /* 40 */ "IdxGE" OpHelp("key=r[P3@P4]"),
+ /* 41 */ "RowSetRead" OpHelp("r[P3]=rowset(P1)"),
+ /* 42 */ "RowSetTest" OpHelp("if r[P3] in rowset(P1) goto P2"),
+ /* 43 */ "Or" OpHelp("r[P3]=(r[P1] || r[P2])"),
+ /* 44 */ "And" OpHelp("r[P3]=(r[P1] && r[P2])"),
+ /* 45 */ "Program" OpHelp(""),
+ /* 46 */ "FkIfZero" OpHelp("if fkctr[P1]==0 goto P2"),
+ /* 47 */ "IfPos" OpHelp("if r[P1]>0 then r[P1]-=P3, goto P2"),
+ /* 48 */ "IfNotZero" OpHelp("if r[P1]!=0 then r[P1]--, goto P2"),
+ /* 49 */ "DecrJumpZero" OpHelp("if (--r[P1])==0 goto P2"),
+ /* 50 */ "IsNull" OpHelp("if r[P1]==NULL goto P2"),
+ /* 51 */ "NotNull" OpHelp("if r[P1]!=NULL goto P2"),
+ /* 52 */ "Ne" OpHelp("IF r[P3]!=r[P1]"),
+ /* 53 */ "Eq" OpHelp("IF r[P3]==r[P1]"),
+ /* 54 */ "Gt" OpHelp("IF r[P3]>r[P1]"),
+ /* 55 */ "Le" OpHelp("IF r[P3]<=r[P1]"),
+ /* 56 */ "Lt" OpHelp("IF r[P3]=r[P1]"),
+ /* 58 */ "ElseNotEq" OpHelp(""),
+ /* 59 */ "IncrVacuum" OpHelp(""),
+ /* 60 */ "VNext" OpHelp(""),
+ /* 61 */ "Init" OpHelp("Start at P2"),
+ /* 62 */ "PureFunc0" OpHelp(""),
+ /* 63 */ "Function0" OpHelp("r[P3]=func(r[P2@P5])"),
+ /* 64 */ "PureFunc" OpHelp(""),
+ /* 65 */ "Function" OpHelp("r[P3]=func(r[P2@P5])"),
+ /* 66 */ "Return" OpHelp(""),
+ /* 67 */ "EndCoroutine" OpHelp(""),
+ /* 68 */ "HaltIfNull" OpHelp("if r[P3]=null halt"),
+ /* 69 */ "Halt" OpHelp(""),
+ /* 70 */ "Integer" OpHelp("r[P2]=P1"),
+ /* 71 */ "Int64" OpHelp("r[P2]=P4"),
+ /* 72 */ "String" OpHelp("r[P2]='P4' (len=P1)"),
+ /* 73 */ "Null" OpHelp("r[P2..P3]=NULL"),
+ /* 74 */ "SoftNull" OpHelp("r[P1]=NULL"),
+ /* 75 */ "Blob" OpHelp("r[P2]=P4 (len=P1)"),
+ /* 76 */ "Variable" OpHelp("r[P2]=parameter(P1,P4)"),
+ /* 77 */ "Move" OpHelp("r[P2@P3]=r[P1@P3]"),
+ /* 78 */ "Copy" OpHelp("r[P2@P3+1]=r[P1@P3+1]"),
+ /* 79 */ "SCopy" OpHelp("r[P2]=r[P1]"),
+ /* 80 */ "IntCopy" OpHelp("r[P2]=r[P1]"),
+ /* 81 */ "ResultRow" OpHelp("output=r[P1@P2]"),
+ /* 82 */ "CollSeq" OpHelp(""),
+ /* 83 */ "AddImm" OpHelp("r[P1]=r[P1]+P2"),
+ /* 84 */ "RealAffinity" OpHelp(""),
+ /* 85 */ "Cast" OpHelp("affinity(r[P1])"),
+ /* 86 */ "Permutation" OpHelp(""),
+ /* 87 */ "Compare" OpHelp("r[P1@P3] <-> r[P2@P3]"),
+ /* 88 */ "IsTrue" OpHelp("r[P2] = coalesce(r[P1]==TRUE,P3) ^ P4"),
+ /* 89 */ "Offset" OpHelp("r[P3] = sqlite_offset(P1)"),
+ /* 90 */ "Column" OpHelp("r[P3]=PX"),
+ /* 91 */ "Affinity" OpHelp("affinity(r[P1@P2])"),
+ /* 92 */ "BitAnd" OpHelp("r[P3]=r[P1]&r[P2]"),
+ /* 93 */ "BitOr" OpHelp("r[P3]=r[P1]|r[P2]"),
+ /* 94 */ "ShiftLeft" OpHelp("r[P3]=r[P2]<>r[P1]"),
+ /* 96 */ "Add" OpHelp("r[P3]=r[P1]+r[P2]"),
+ /* 97 */ "Subtract" OpHelp("r[P3]=r[P2]-r[P1]"),
+ /* 98 */ "Multiply" OpHelp("r[P3]=r[P1]*r[P2]"),
+ /* 99 */ "Divide" OpHelp("r[P3]=r[P2]/r[P1]"),
+ /* 100 */ "Remainder" OpHelp("r[P3]=r[P2]%r[P1]"),
+ /* 101 */ "Concat" OpHelp("r[P3]=r[P2]+r[P1]"),
+ /* 102 */ "MakeRecord" OpHelp("r[P3]=mkrec(r[P1@P2])"),
+ /* 103 */ "BitNot" OpHelp("r[P2]= ~r[P1]"),
+ /* 104 */ "Count" OpHelp("r[P2]=count()"),
+ /* 105 */ "ReadCookie" OpHelp(""),
+ /* 106 */ "String8" OpHelp("r[P2]='P4'"),
+ /* 107 */ "SetCookie" OpHelp(""),
+ /* 108 */ "ReopenIdx" OpHelp("root=P2 iDb=P3"),
+ /* 109 */ "OpenRead" OpHelp("root=P2 iDb=P3"),
+ /* 110 */ "OpenWrite" OpHelp("root=P2 iDb=P3"),
+ /* 111 */ "OpenDup" OpHelp(""),
+ /* 112 */ "OpenAutoindex" OpHelp("nColumn=P2"),
+ /* 113 */ "OpenEphemeral" OpHelp("nColumn=P2"),
+ /* 114 */ "SorterOpen" OpHelp(""),
+ /* 115 */ "SequenceTest" OpHelp("if( cursor[P1].ctr++ ) pc = P2"),
+ /* 116 */ "OpenPseudo" OpHelp("P3 columns in r[P2]"),
+ /* 117 */ "Close" OpHelp(""),
+ /* 118 */ "ColumnsUsed" OpHelp(""),
+ /* 119 */ "SeekHit" OpHelp("seekHit=P2"),
+ /* 120 */ "Sequence" OpHelp("r[P2]=cursor[P1].ctr++"),
+ /* 121 */ "NewRowid" OpHelp("r[P2]=rowid"),
+ /* 122 */ "Insert" OpHelp("intkey=r[P3] data=r[P2]"),
+ /* 123 */ "InsertInt" OpHelp("intkey=P3 data=r[P2]"),
+ /* 124 */ "Delete" OpHelp(""),
+ /* 125 */ "ResetCount" OpHelp(""),
+ /* 126 */ "SorterCompare" OpHelp("if key(P1)!=trim(r[P3],P4) goto P2"),
+ /* 127 */ "SorterData" OpHelp("r[P2]=data"),
+ /* 128 */ "RowData" OpHelp("r[P2]=data"),
+ /* 129 */ "Rowid" OpHelp("r[P2]=rowid"),
+ /* 130 */ "NullRow" OpHelp(""),
+ /* 131 */ "SeekEnd" OpHelp(""),
+ /* 132 */ "SorterInsert" OpHelp("key=r[P2]"),
+ /* 133 */ "IdxInsert" OpHelp("key=r[P2]"),
+ /* 134 */ "IdxDelete" OpHelp("key=r[P2@P3]"),
+ /* 135 */ "DeferredSeek" OpHelp("Move P3 to P1.rowid if needed"),
+ /* 136 */ "IdxRowid" OpHelp("r[P2]=rowid"),
+ /* 137 */ "Destroy" OpHelp(""),
+ /* 138 */ "Clear" OpHelp(""),
+ /* 139 */ "ResetSorter" OpHelp(""),
+ /* 140 */ "CreateBtree" OpHelp("r[P2]=root iDb=P1 flags=P3"),
+ /* 141 */ "Real" OpHelp("r[P2]=P4"),
+ /* 142 */ "SqlExec" OpHelp(""),
+ /* 143 */ "ParseSchema" OpHelp(""),
+ /* 144 */ "LoadAnalysis" OpHelp(""),
+ /* 145 */ "DropTable" OpHelp(""),
+ /* 146 */ "DropIndex" OpHelp(""),
+ /* 147 */ "DropTrigger" OpHelp(""),
+ /* 148 */ "IntegrityCk" OpHelp(""),
+ /* 149 */ "RowSetAdd" OpHelp("rowset(P1)=r[P2]"),
+ /* 150 */ "Param" OpHelp(""),
+ /* 151 */ "FkCounter" OpHelp("fkctr[P1]+=P2"),
+ /* 152 */ "MemMax" OpHelp("r[P1]=max(r[P1],r[P2])"),
+ /* 153 */ "OffsetLimit" OpHelp("if r[P1]>0 then r[P2]=r[P1]+max(0,r[P3]) else r[P2]=(-1)"),
+ /* 154 */ "AggInverse" OpHelp("accum=r[P3] inverse(r[P2@P5])"),
+ /* 155 */ "AggStep" OpHelp("accum=r[P3] step(r[P2@P5])"),
+ /* 156 */ "AggStep1" OpHelp("accum=r[P3] step(r[P2@P5])"),
+ /* 157 */ "AggValue" OpHelp("r[P3]=value N=P2"),
+ /* 158 */ "AggFinal" OpHelp("accum=r[P1] N=P2"),
+ /* 159 */ "Expire" OpHelp(""),
+ /* 160 */ "TableLock" OpHelp("iDb=P1 root=P2 write=P3"),
+ /* 161 */ "VBegin" OpHelp(""),
+ /* 162 */ "VCreate" OpHelp(""),
+ /* 163 */ "VDestroy" OpHelp(""),
+ /* 164 */ "VOpen" OpHelp(""),
+ /* 165 */ "VColumn" OpHelp("r[P3]=vcolumn(P2)"),
+ /* 166 */ "VRename" OpHelp(""),
+ /* 167 */ "Pagecount" OpHelp(""),
+ /* 168 */ "MaxPgcnt" OpHelp(""),
+ /* 169 */ "Trace" OpHelp(""),
+ /* 170 */ "CursorHint" OpHelp(""),
+ /* 171 */ "Noop" OpHelp(""),
+ /* 172 */ "Explain" OpHelp(""),
+ /* 173 */ "Abortable" OpHelp(""),
+ };
+ return azName[i];
+}
+#endif
+
+/************** End of opcodes.c *********************************************/
+/************** Begin file os_unix.c *****************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains the VFS implementation for unix-like operating systems
+** include Linux, MacOSX, *BSD, QNX, VxWorks, AIX, HPUX, and others.
+**
+** There are actually several different VFS implementations in this file.
+** The differences are in the way that file locking is done. The default
+** implementation uses Posix Advisory Locks. Alternative implementations
+** use flock(), dot-files, various proprietary locking schemas, or simply
+** skip locking all together.
+**
+** This source file is organized into divisions where the logic for various
+** subfunctions is contained within the appropriate division. PLEASE
+** KEEP THE STRUCTURE OF THIS FILE INTACT. New code should be placed
+** in the correct division and should be clearly labeled.
+**
+** The layout of divisions is as follows:
+**
+** * General-purpose declarations and utility functions.
+** * Unique file ID logic used by VxWorks.
+** * Various locking primitive implementations (all except proxy locking):
+** + for Posix Advisory Locks
+** + for no-op locks
+** + for dot-file locks
+** + for flock() locking
+** + for named semaphore locks (VxWorks only)
+** + for AFP filesystem locks (MacOSX only)
+** * sqlite3_file methods not associated with locking.
+** * Definitions of sqlite3_io_methods objects for all locking
+** methods plus "finder" functions for each locking method.
+** * sqlite3_vfs method implementations.
+** * Locking primitives for the proxy uber-locking-method. (MacOSX only)
+** * Definitions of sqlite3_vfs objects for all locking methods
+** plus implementations of sqlite3_os_init() and sqlite3_os_end().
+*/
+/* #include "sqliteInt.h" */
+#if SQLITE_OS_UNIX /* This file is used on unix only */
+
+/*
+** There are various methods for file locking used for concurrency
+** control:
+**
+** 1. POSIX locking (the default),
+** 2. No locking,
+** 3. Dot-file locking,
+** 4. flock() locking,
+** 5. AFP locking (OSX only),
+** 6. Named POSIX semaphores (VXWorks only),
+** 7. proxy locking. (OSX only)
+**
+** Styles 4, 5, and 7 are only available of SQLITE_ENABLE_LOCKING_STYLE
+** is defined to 1. The SQLITE_ENABLE_LOCKING_STYLE also enables automatic
+** selection of the appropriate locking style based on the filesystem
+** where the database is located.
+*/
+#if !defined(SQLITE_ENABLE_LOCKING_STYLE)
+# if defined(__APPLE__)
+# define SQLITE_ENABLE_LOCKING_STYLE 1
+# else
+# define SQLITE_ENABLE_LOCKING_STYLE 0
+# endif
+#endif
+
+/* Use pread() and pwrite() if they are available */
+#if defined(__APPLE__)
+# define HAVE_PREAD 1
+# define HAVE_PWRITE 1
+#endif
+#if defined(HAVE_PREAD64) && defined(HAVE_PWRITE64)
+# undef USE_PREAD
+# define USE_PREAD64 1
+#elif defined(HAVE_PREAD) && defined(HAVE_PWRITE)
+# undef USE_PREAD64
+# define USE_PREAD 1
+#endif
+
+/*
+** standard include files.
+*/
+#include
+#include
+#include
+#include
+#include
+/* #include */
+#include
+#include
+#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
+# include
+#endif
+
+#if SQLITE_ENABLE_LOCKING_STYLE
+/* # include */
+# include
+# include
+#endif /* SQLITE_ENABLE_LOCKING_STYLE */
+
+#if defined(__APPLE__) && ((__MAC_OS_X_VERSION_MIN_REQUIRED > 1050) || \
+ (__IPHONE_OS_VERSION_MIN_REQUIRED > 2000))
+# if (!defined(TARGET_OS_EMBEDDED) || (TARGET_OS_EMBEDDED==0)) \
+ && (!defined(TARGET_IPHONE_SIMULATOR) || (TARGET_IPHONE_SIMULATOR==0))
+# define HAVE_GETHOSTUUID 1
+# else
+# warning "gethostuuid() is disabled."
+# endif
+#endif
+
+
+#if OS_VXWORKS
+/* # include */
+# include
+# include
+#endif /* OS_VXWORKS */
+
+#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE
+# include
+#endif
+
+#ifdef HAVE_UTIME
+# include
+#endif
+
+/*
+** Allowed values of unixFile.fsFlags
+*/
+#define SQLITE_FSFLAGS_IS_MSDOS 0x1
+
+/*
+** If we are to be thread-safe, include the pthreads header and define
+** the SQLITE_UNIX_THREADS macro.
+*/
+#if SQLITE_THREADSAFE
+/* # include */
+# define SQLITE_UNIX_THREADS 1
+#endif
+
+/*
+** Default permissions when creating a new file
+*/
+#ifndef SQLITE_DEFAULT_FILE_PERMISSIONS
+# define SQLITE_DEFAULT_FILE_PERMISSIONS 0644
+#endif
+
+/*
+** Default permissions when creating auto proxy dir
+*/
+#ifndef SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
+# define SQLITE_DEFAULT_PROXYDIR_PERMISSIONS 0755
+#endif
+
+/*
+** Maximum supported path-length.
+*/
+#define MAX_PATHNAME 512
+
+/*
+** Maximum supported symbolic links
+*/
+#define SQLITE_MAX_SYMLINKS 100
+
+/* Always cast the getpid() return type for compatibility with
+** kernel modules in VxWorks. */
+#define osGetpid(X) (pid_t)getpid()
+
+/*
+** Only set the lastErrno if the error code is a real error and not
+** a normal expected return code of SQLITE_BUSY or SQLITE_OK
+*/
+#define IS_LOCK_ERROR(x) ((x != SQLITE_OK) && (x != SQLITE_BUSY))
+
+/* Forward references */
+typedef struct unixShm unixShm; /* Connection shared memory */
+typedef struct unixShmNode unixShmNode; /* Shared memory instance */
+typedef struct unixInodeInfo unixInodeInfo; /* An i-node */
+typedef struct UnixUnusedFd UnixUnusedFd; /* An unused file descriptor */
+
+/*
+** Sometimes, after a file handle is closed by SQLite, the file descriptor
+** cannot be closed immediately. In these cases, instances of the following
+** structure are used to store the file descriptor while waiting for an
+** opportunity to either close or reuse it.
+*/
+struct UnixUnusedFd {
+ int fd; /* File descriptor to close */
+ int flags; /* Flags this file descriptor was opened with */
+ UnixUnusedFd *pNext; /* Next unused file descriptor on same file */
+};
+
+/*
+** The unixFile structure is subclass of sqlite3_file specific to the unix
+** VFS implementations.
+*/
+typedef struct unixFile unixFile;
+struct unixFile {
+ sqlite3_io_methods const *pMethod; /* Always the first entry */
+ sqlite3_vfs *pVfs; /* The VFS that created this unixFile */
+ unixInodeInfo *pInode; /* Info about locks on this inode */
+ int h; /* The file descriptor */
+ unsigned char eFileLock; /* The type of lock held on this fd */
+ unsigned short int ctrlFlags; /* Behavioral bits. UNIXFILE_* flags */
+ int lastErrno; /* The unix errno from last I/O error */
+ void *lockingContext; /* Locking style specific state */
+ UnixUnusedFd *pPreallocatedUnused; /* Pre-allocated UnixUnusedFd */
+ const char *zPath; /* Name of the file */
+ unixShm *pShm; /* Shared memory segment information */
+ int szChunk; /* Configured by FCNTL_CHUNK_SIZE */
+#if SQLITE_MAX_MMAP_SIZE>0
+ int nFetchOut; /* Number of outstanding xFetch refs */
+ sqlite3_int64 mmapSize; /* Usable size of mapping at pMapRegion */
+ sqlite3_int64 mmapSizeActual; /* Actual size of mapping at pMapRegion */
+ sqlite3_int64 mmapSizeMax; /* Configured FCNTL_MMAP_SIZE value */
+ void *pMapRegion; /* Memory mapped region */
+#endif
+ int sectorSize; /* Device sector size */
+ int deviceCharacteristics; /* Precomputed device characteristics */
+#if SQLITE_ENABLE_LOCKING_STYLE
+ int openFlags; /* The flags specified at open() */
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE || defined(__APPLE__)
+ unsigned fsFlags; /* cached details from statfs() */
+#endif
+#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
+ unsigned iBusyTimeout; /* Wait this many millisec on locks */
+#endif
+#if OS_VXWORKS
+ struct vxworksFileId *pId; /* Unique file ID */
+#endif
+#ifdef SQLITE_DEBUG
+ /* The next group of variables are used to track whether or not the
+ ** transaction counter in bytes 24-27 of database files are updated
+ ** whenever any part of the database changes. An assertion fault will
+ ** occur if a file is updated without also updating the transaction
+ ** counter. This test is made to avoid new problems similar to the
+ ** one described by ticket #3584.
+ */
+ unsigned char transCntrChng; /* True if the transaction counter changed */
+ unsigned char dbUpdate; /* True if any part of database file changed */
+ unsigned char inNormalWrite; /* True if in a normal write operation */
+
+#endif
+
+#ifdef SQLITE_TEST
+ /* In test mode, increase the size of this structure a bit so that
+ ** it is larger than the struct CrashFile defined in test6.c.
+ */
+ char aPadding[32];
+#endif
+};
+
+/* This variable holds the process id (pid) from when the xRandomness()
+** method was called. If xOpen() is called from a different process id,
+** indicating that a fork() has occurred, the PRNG will be reset.
+*/
+static pid_t randomnessPid = 0;
+
+/*
+** Allowed values for the unixFile.ctrlFlags bitmask:
+*/
+#define UNIXFILE_EXCL 0x01 /* Connections from one process only */
+#define UNIXFILE_RDONLY 0x02 /* Connection is read only */
+#define UNIXFILE_PERSIST_WAL 0x04 /* Persistent WAL mode */
+#ifndef SQLITE_DISABLE_DIRSYNC
+# define UNIXFILE_DIRSYNC 0x08 /* Directory sync needed */
+#else
+# define UNIXFILE_DIRSYNC 0x00
+#endif
+#define UNIXFILE_PSOW 0x10 /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
+#define UNIXFILE_DELETE 0x20 /* Delete on close */
+#define UNIXFILE_URI 0x40 /* Filename might have query parameters */
+#define UNIXFILE_NOLOCK 0x80 /* Do no file locking */
+
+/*
+** Include code that is common to all os_*.c files
+*/
+/************** Include os_common.h in the middle of os_unix.c ***************/
+/************** Begin file os_common.h ***************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains macros and a little bit of code that is common to
+** all of the platform-specific files (os_*.c) and is #included into those
+** files.
+**
+** This file should be #included by the os_*.c files only. It is not a
+** general purpose header file.
+*/
+#ifndef _OS_COMMON_H_
+#define _OS_COMMON_H_
+
+/*
+** At least two bugs have slipped in because we changed the MEMORY_DEBUG
+** macro to SQLITE_DEBUG and some older makefiles have not yet made the
+** switch. The following code should catch this problem at compile-time.
+*/
+#ifdef MEMORY_DEBUG
+# error "The MEMORY_DEBUG macro is obsolete. Use SQLITE_DEBUG instead."
+#endif
+
+/*
+** Macros for performance tracing. Normally turned off. Only works
+** on i486 hardware.
+*/
+#ifdef SQLITE_PERFORMANCE_TRACE
+
+/*
+** hwtime.h contains inline assembler code for implementing
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of os_common.h ****************/
+/************** Begin file hwtime.h ******************************************/
+/*
+** 2008 May 27
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
+*/
+#ifndef SQLITE_HWTIME_H
+#define SQLITE_HWTIME_H
+
+/*
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value. This can be used for high-res
+** profiling.
+*/
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+ (defined(i386) || defined(__i386__) || defined(_M_IX86))
+
+ #if defined(__GNUC__)
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned int lo, hi;
+ __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+ return (sqlite_uint64)hi << 32 | lo;
+ }
+
+ #elif defined(_MSC_VER)
+
+ __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+ __asm {
+ rdtsc
+ ret ; return value at EDX:EAX
+ }
+ }
+
+ #endif
+
+#elif (defined(__GNUC__) && defined(__x86_64__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long val;
+ __asm__ __volatile__ ("rdtsc" : "=A" (val));
+ return val;
+ }
+
+#elif (defined(__GNUC__) && defined(__ppc__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long long retval;
+ unsigned long junk;
+ __asm__ __volatile__ ("\n\
+ 1: mftbu %1\n\
+ mftb %L0\n\
+ mftbu %0\n\
+ cmpw %0,%1\n\
+ bne 1b"
+ : "=r" (retval), "=r" (junk));
+ return retval;
+ }
+
+#else
+
+ #error Need implementation of sqlite3Hwtime() for your platform.
+
+ /*
+ ** To compile without implementing sqlite3Hwtime() for your platform,
+ ** you can remove the above #error and use the following
+ ** stub function. You will lose timing support for many
+ ** of the debugging and testing utilities, but it should at
+ ** least compile and run.
+ */
+SQLITE_PRIVATE sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
+
+#endif
+
+#endif /* !defined(SQLITE_HWTIME_H) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in os_common.h ******************/
+
+static sqlite_uint64 g_start;
+static sqlite_uint64 g_elapsed;
+#define TIMER_START g_start=sqlite3Hwtime()
+#define TIMER_END g_elapsed=sqlite3Hwtime()-g_start
+#define TIMER_ELAPSED g_elapsed
+#else
+#define TIMER_START
+#define TIMER_END
+#define TIMER_ELAPSED ((sqlite_uint64)0)
+#endif
+
+/*
+** If we compile with the SQLITE_TEST macro set, then the following block
+** of code will give us the ability to simulate a disk I/O error. This
+** is used for testing the I/O recovery logic.
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API extern int sqlite3_io_error_hit;
+SQLITE_API extern int sqlite3_io_error_hardhit;
+SQLITE_API extern int sqlite3_io_error_pending;
+SQLITE_API extern int sqlite3_io_error_persist;
+SQLITE_API extern int sqlite3_io_error_benign;
+SQLITE_API extern int sqlite3_diskfull_pending;
+SQLITE_API extern int sqlite3_diskfull;
+#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
+#define SimulateIOError(CODE) \
+ if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
+ || sqlite3_io_error_pending-- == 1 ) \
+ { local_ioerr(); CODE; }
+static void local_ioerr(){
+ IOTRACE(("IOERR\n"));
+ sqlite3_io_error_hit++;
+ if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
+}
+#define SimulateDiskfullError(CODE) \
+ if( sqlite3_diskfull_pending ){ \
+ if( sqlite3_diskfull_pending == 1 ){ \
+ local_ioerr(); \
+ sqlite3_diskfull = 1; \
+ sqlite3_io_error_hit = 1; \
+ CODE; \
+ }else{ \
+ sqlite3_diskfull_pending--; \
+ } \
+ }
+#else
+#define SimulateIOErrorBenign(X)
+#define SimulateIOError(A)
+#define SimulateDiskfullError(A)
+#endif /* defined(SQLITE_TEST) */
+
+/*
+** When testing, keep a count of the number of open files.
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API extern int sqlite3_open_file_count;
+#define OpenCounter(X) sqlite3_open_file_count+=(X)
+#else
+#define OpenCounter(X)
+#endif /* defined(SQLITE_TEST) */
+
+#endif /* !defined(_OS_COMMON_H_) */
+
+/************** End of os_common.h *******************************************/
+/************** Continuing where we left off in os_unix.c ********************/
+
+/*
+** Define various macros that are missing from some systems.
+*/
+#ifndef O_LARGEFILE
+# define O_LARGEFILE 0
+#endif
+#ifdef SQLITE_DISABLE_LFS
+# undef O_LARGEFILE
+# define O_LARGEFILE 0
+#endif
+#ifndef O_NOFOLLOW
+# define O_NOFOLLOW 0
+#endif
+#ifndef O_BINARY
+# define O_BINARY 0
+#endif
+
+/*
+** The threadid macro resolves to the thread-id or to 0. Used for
+** testing and debugging only.
+*/
+#if SQLITE_THREADSAFE
+#define threadid pthread_self()
+#else
+#define threadid 0
+#endif
+
+/*
+** HAVE_MREMAP defaults to true on Linux and false everywhere else.
+*/
+#if !defined(HAVE_MREMAP)
+# if defined(__linux__) && defined(_GNU_SOURCE)
+# define HAVE_MREMAP 1
+# else
+# define HAVE_MREMAP 0
+# endif
+#endif
+
+/*
+** Explicitly call the 64-bit version of lseek() on Android. Otherwise, lseek()
+** is the 32-bit version, even if _FILE_OFFSET_BITS=64 is defined.
+*/
+#ifdef __ANDROID__
+# define lseek lseek64
+#endif
+
+#ifdef __linux__
+/*
+** Linux-specific IOCTL magic numbers used for controlling F2FS
+*/
+#define F2FS_IOCTL_MAGIC 0xf5
+#define F2FS_IOC_START_ATOMIC_WRITE _IO(F2FS_IOCTL_MAGIC, 1)
+#define F2FS_IOC_COMMIT_ATOMIC_WRITE _IO(F2FS_IOCTL_MAGIC, 2)
+#define F2FS_IOC_START_VOLATILE_WRITE _IO(F2FS_IOCTL_MAGIC, 3)
+#define F2FS_IOC_ABORT_VOLATILE_WRITE _IO(F2FS_IOCTL_MAGIC, 5)
+#define F2FS_IOC_GET_FEATURES _IOR(F2FS_IOCTL_MAGIC, 12, u32)
+#define F2FS_FEATURE_ATOMIC_WRITE 0x0004
+#endif /* __linux__ */
+
+
+/*
+** Different Unix systems declare open() in different ways. Same use
+** open(const char*,int,mode_t). Others use open(const char*,int,...).
+** The difference is important when using a pointer to the function.
+**
+** The safest way to deal with the problem is to always use this wrapper
+** which always has the same well-defined interface.
+*/
+static int posixOpen(const char *zFile, int flags, int mode){
+ return open(zFile, flags, mode);
+}
+
+/* Forward reference */
+static int openDirectory(const char*, int*);
+static int unixGetpagesize(void);
+
+/*
+** Many system calls are accessed through pointer-to-functions so that
+** they may be overridden at runtime to facilitate fault injection during
+** testing and sandboxing. The following array holds the names and pointers
+** to all overrideable system calls.
+*/
+static struct unix_syscall {
+ const char *zName; /* Name of the system call */
+ sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
+ sqlite3_syscall_ptr pDefault; /* Default value */
+} aSyscall[] = {
+ { "open", (sqlite3_syscall_ptr)posixOpen, 0 },
+#define osOpen ((int(*)(const char*,int,int))aSyscall[0].pCurrent)
+
+ { "close", (sqlite3_syscall_ptr)close, 0 },
+#define osClose ((int(*)(int))aSyscall[1].pCurrent)
+
+ { "access", (sqlite3_syscall_ptr)access, 0 },
+#define osAccess ((int(*)(const char*,int))aSyscall[2].pCurrent)
+
+ { "getcwd", (sqlite3_syscall_ptr)getcwd, 0 },
+#define osGetcwd ((char*(*)(char*,size_t))aSyscall[3].pCurrent)
+
+ { "stat", (sqlite3_syscall_ptr)stat, 0 },
+#define osStat ((int(*)(const char*,struct stat*))aSyscall[4].pCurrent)
+
+/*
+** The DJGPP compiler environment looks mostly like Unix, but it
+** lacks the fcntl() system call. So redefine fcntl() to be something
+** that always succeeds. This means that locking does not occur under
+** DJGPP. But it is DOS - what did you expect?
+*/
+#ifdef __DJGPP__
+ { "fstat", 0, 0 },
+#define osFstat(a,b,c) 0
+#else
+ { "fstat", (sqlite3_syscall_ptr)fstat, 0 },
+#define osFstat ((int(*)(int,struct stat*))aSyscall[5].pCurrent)
+#endif
+
+ { "ftruncate", (sqlite3_syscall_ptr)ftruncate, 0 },
+#define osFtruncate ((int(*)(int,off_t))aSyscall[6].pCurrent)
+
+ { "fcntl", (sqlite3_syscall_ptr)fcntl, 0 },
+#define osFcntl ((int(*)(int,int,...))aSyscall[7].pCurrent)
+
+ { "read", (sqlite3_syscall_ptr)read, 0 },
+#define osRead ((ssize_t(*)(int,void*,size_t))aSyscall[8].pCurrent)
+
+#if defined(USE_PREAD) || SQLITE_ENABLE_LOCKING_STYLE
+ { "pread", (sqlite3_syscall_ptr)pread, 0 },
+#else
+ { "pread", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osPread ((ssize_t(*)(int,void*,size_t,off_t))aSyscall[9].pCurrent)
+
+#if defined(USE_PREAD64)
+ { "pread64", (sqlite3_syscall_ptr)pread64, 0 },
+#else
+ { "pread64", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osPread64 ((ssize_t(*)(int,void*,size_t,off64_t))aSyscall[10].pCurrent)
+
+ { "write", (sqlite3_syscall_ptr)write, 0 },
+#define osWrite ((ssize_t(*)(int,const void*,size_t))aSyscall[11].pCurrent)
+
+#if defined(USE_PREAD) || SQLITE_ENABLE_LOCKING_STYLE
+ { "pwrite", (sqlite3_syscall_ptr)pwrite, 0 },
+#else
+ { "pwrite", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osPwrite ((ssize_t(*)(int,const void*,size_t,off_t))\
+ aSyscall[12].pCurrent)
+
+#if defined(USE_PREAD64)
+ { "pwrite64", (sqlite3_syscall_ptr)pwrite64, 0 },
+#else
+ { "pwrite64", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osPwrite64 ((ssize_t(*)(int,const void*,size_t,off64_t))\
+ aSyscall[13].pCurrent)
+
+ { "fchmod", (sqlite3_syscall_ptr)fchmod, 0 },
+#define osFchmod ((int(*)(int,mode_t))aSyscall[14].pCurrent)
+
+#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
+ { "fallocate", (sqlite3_syscall_ptr)posix_fallocate, 0 },
+#else
+ { "fallocate", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osFallocate ((int(*)(int,off_t,off_t))aSyscall[15].pCurrent)
+
+ { "unlink", (sqlite3_syscall_ptr)unlink, 0 },
+#define osUnlink ((int(*)(const char*))aSyscall[16].pCurrent)
+
+ { "openDirectory", (sqlite3_syscall_ptr)openDirectory, 0 },
+#define osOpenDirectory ((int(*)(const char*,int*))aSyscall[17].pCurrent)
+
+ { "mkdir", (sqlite3_syscall_ptr)mkdir, 0 },
+#define osMkdir ((int(*)(const char*,mode_t))aSyscall[18].pCurrent)
+
+ { "rmdir", (sqlite3_syscall_ptr)rmdir, 0 },
+#define osRmdir ((int(*)(const char*))aSyscall[19].pCurrent)
+
+#if defined(HAVE_FCHOWN)
+ { "fchown", (sqlite3_syscall_ptr)fchown, 0 },
+#else
+ { "fchown", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osFchown ((int(*)(int,uid_t,gid_t))aSyscall[20].pCurrent)
+
+#if defined(HAVE_FCHOWN)
+ { "geteuid", (sqlite3_syscall_ptr)geteuid, 0 },
+#else
+ { "geteuid", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osGeteuid ((uid_t(*)(void))aSyscall[21].pCurrent)
+
+#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
+ { "mmap", (sqlite3_syscall_ptr)mmap, 0 },
+#else
+ { "mmap", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osMmap ((void*(*)(void*,size_t,int,int,int,off_t))aSyscall[22].pCurrent)
+
+#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
+ { "munmap", (sqlite3_syscall_ptr)munmap, 0 },
+#else
+ { "munmap", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osMunmap ((int(*)(void*,size_t))aSyscall[23].pCurrent)
+
+#if HAVE_MREMAP && (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
+ { "mremap", (sqlite3_syscall_ptr)mremap, 0 },
+#else
+ { "mremap", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osMremap ((void*(*)(void*,size_t,size_t,int,...))aSyscall[24].pCurrent)
+
+#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
+ { "getpagesize", (sqlite3_syscall_ptr)unixGetpagesize, 0 },
+#else
+ { "getpagesize", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osGetpagesize ((int(*)(void))aSyscall[25].pCurrent)
+
+#if defined(HAVE_READLINK)
+ { "readlink", (sqlite3_syscall_ptr)readlink, 0 },
+#else
+ { "readlink", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osReadlink ((ssize_t(*)(const char*,char*,size_t))aSyscall[26].pCurrent)
+
+#if defined(HAVE_LSTAT)
+ { "lstat", (sqlite3_syscall_ptr)lstat, 0 },
+#else
+ { "lstat", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osLstat ((int(*)(const char*,struct stat*))aSyscall[27].pCurrent)
+
+#if defined(__linux__) && defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
+# ifdef __ANDROID__
+ { "ioctl", (sqlite3_syscall_ptr)(int(*)(int, int, ...))ioctl, 0 },
+# else
+ { "ioctl", (sqlite3_syscall_ptr)ioctl, 0 },
+# endif
+#else
+ { "ioctl", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osIoctl ((int(*)(int,int,...))aSyscall[28].pCurrent)
+
+}; /* End of the overrideable system calls */
+
+
+/*
+** On some systems, calls to fchown() will trigger a message in a security
+** log if they come from non-root processes. So avoid calling fchown() if
+** we are not running as root.
+*/
+static int robustFchown(int fd, uid_t uid, gid_t gid){
+#if defined(HAVE_FCHOWN)
+ return osGeteuid() ? 0 : osFchown(fd,uid,gid);
+#else
+ return 0;
+#endif
+}
+
+/*
+** This is the xSetSystemCall() method of sqlite3_vfs for all of the
+** "unix" VFSes. Return SQLITE_OK opon successfully updating the
+** system call pointer, or SQLITE_NOTFOUND if there is no configurable
+** system call named zName.
+*/
+static int unixSetSystemCall(
+ sqlite3_vfs *pNotUsed, /* The VFS pointer. Not used */
+ const char *zName, /* Name of system call to override */
+ sqlite3_syscall_ptr pNewFunc /* Pointer to new system call value */
+){
+ unsigned int i;
+ int rc = SQLITE_NOTFOUND;
+
+ UNUSED_PARAMETER(pNotUsed);
+ if( zName==0 ){
+ /* If no zName is given, restore all system calls to their default
+ ** settings and return NULL
+ */
+ rc = SQLITE_OK;
+ for(i=0; i=SQLITE_MINIMUM_FILE_DESCRIPTOR ) break;
+ osClose(fd);
+ sqlite3_log(SQLITE_WARNING,
+ "attempt to open \"%s\" as file descriptor %d", z, fd);
+ fd = -1;
+ if( osOpen("/dev/null", f, m)<0 ) break;
+ }
+ if( fd>=0 ){
+ if( m!=0 ){
+ struct stat statbuf;
+ if( osFstat(fd, &statbuf)==0
+ && statbuf.st_size==0
+ && (statbuf.st_mode&0777)!=m
+ ){
+ osFchmod(fd, m);
+ }
+ }
+#if defined(FD_CLOEXEC) && (!defined(O_CLOEXEC) || O_CLOEXEC==0)
+ osFcntl(fd, F_SETFD, osFcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
+#endif
+ }
+ return fd;
+}
+
+/*
+** Helper functions to obtain and relinquish the global mutex. The
+** global mutex is used to protect the unixInodeInfo and
+** vxworksFileId objects used by this file, all of which may be
+** shared by multiple threads.
+**
+** Function unixMutexHeld() is used to assert() that the global mutex
+** is held when required. This function is only used as part of assert()
+** statements. e.g.
+**
+** unixEnterMutex()
+** assert( unixMutexHeld() );
+** unixEnterLeave()
+**
+** To prevent deadlock, the global unixBigLock must must be acquired
+** before the unixInodeInfo.pLockMutex mutex, if both are held. It is
+** OK to get the pLockMutex without holding unixBigLock first, but if
+** that happens, the unixBigLock mutex must not be acquired until after
+** pLockMutex is released.
+**
+** OK: enter(unixBigLock), enter(pLockInfo)
+** OK: enter(unixBigLock)
+** OK: enter(pLockInfo)
+** ERROR: enter(pLockInfo), enter(unixBigLock)
+*/
+static sqlite3_mutex *unixBigLock = 0;
+static void unixEnterMutex(void){
+ assert( sqlite3_mutex_notheld(unixBigLock) ); /* Not a recursive mutex */
+ sqlite3_mutex_enter(unixBigLock);
+}
+static void unixLeaveMutex(void){
+ assert( sqlite3_mutex_held(unixBigLock) );
+ sqlite3_mutex_leave(unixBigLock);
+}
+#ifdef SQLITE_DEBUG
+static int unixMutexHeld(void) {
+ return sqlite3_mutex_held(unixBigLock);
+}
+#endif
+
+
+#ifdef SQLITE_HAVE_OS_TRACE
+/*
+** Helper function for printing out trace information from debugging
+** binaries. This returns the string representation of the supplied
+** integer lock-type.
+*/
+static const char *azFileLock(int eFileLock){
+ switch( eFileLock ){
+ case NO_LOCK: return "NONE";
+ case SHARED_LOCK: return "SHARED";
+ case RESERVED_LOCK: return "RESERVED";
+ case PENDING_LOCK: return "PENDING";
+ case EXCLUSIVE_LOCK: return "EXCLUSIVE";
+ }
+ return "ERROR";
+}
+#endif
+
+#ifdef SQLITE_LOCK_TRACE
+/*
+** Print out information about all locking operations.
+**
+** This routine is used for troubleshooting locks on multithreaded
+** platforms. Enable by compiling with the -DSQLITE_LOCK_TRACE
+** command-line option on the compiler. This code is normally
+** turned off.
+*/
+static int lockTrace(int fd, int op, struct flock *p){
+ char *zOpName, *zType;
+ int s;
+ int savedErrno;
+ if( op==F_GETLK ){
+ zOpName = "GETLK";
+ }else if( op==F_SETLK ){
+ zOpName = "SETLK";
+ }else{
+ s = osFcntl(fd, op, p);
+ sqlite3DebugPrintf("fcntl unknown %d %d %d\n", fd, op, s);
+ return s;
+ }
+ if( p->l_type==F_RDLCK ){
+ zType = "RDLCK";
+ }else if( p->l_type==F_WRLCK ){
+ zType = "WRLCK";
+ }else if( p->l_type==F_UNLCK ){
+ zType = "UNLCK";
+ }else{
+ assert( 0 );
+ }
+ assert( p->l_whence==SEEK_SET );
+ s = osFcntl(fd, op, p);
+ savedErrno = errno;
+ sqlite3DebugPrintf("fcntl %d %d %s %s %d %d %d %d\n",
+ threadid, fd, zOpName, zType, (int)p->l_start, (int)p->l_len,
+ (int)p->l_pid, s);
+ if( s==(-1) && op==F_SETLK && (p->l_type==F_RDLCK || p->l_type==F_WRLCK) ){
+ struct flock l2;
+ l2 = *p;
+ osFcntl(fd, F_GETLK, &l2);
+ if( l2.l_type==F_RDLCK ){
+ zType = "RDLCK";
+ }else if( l2.l_type==F_WRLCK ){
+ zType = "WRLCK";
+ }else if( l2.l_type==F_UNLCK ){
+ zType = "UNLCK";
+ }else{
+ assert( 0 );
+ }
+ sqlite3DebugPrintf("fcntl-failure-reason: %s %d %d %d\n",
+ zType, (int)l2.l_start, (int)l2.l_len, (int)l2.l_pid);
+ }
+ errno = savedErrno;
+ return s;
+}
+#undef osFcntl
+#define osFcntl lockTrace
+#endif /* SQLITE_LOCK_TRACE */
+
+/*
+** Retry ftruncate() calls that fail due to EINTR
+**
+** All calls to ftruncate() within this file should be made through
+** this wrapper. On the Android platform, bypassing the logic below
+** could lead to a corrupt database.
+*/
+static int robust_ftruncate(int h, sqlite3_int64 sz){
+ int rc;
+#ifdef __ANDROID__
+ /* On Android, ftruncate() always uses 32-bit offsets, even if
+ ** _FILE_OFFSET_BITS=64 is defined. This means it is unsafe to attempt to
+ ** truncate a file to any size larger than 2GiB. Silently ignore any
+ ** such attempts. */
+ if( sz>(sqlite3_int64)0x7FFFFFFF ){
+ rc = SQLITE_OK;
+ }else
+#endif
+ do{ rc = osFtruncate(h,sz); }while( rc<0 && errno==EINTR );
+ return rc;
+}
+
+/*
+** This routine translates a standard POSIX errno code into something
+** useful to the clients of the sqlite3 functions. Specifically, it is
+** intended to translate a variety of "try again" errors into SQLITE_BUSY
+** and a variety of "please close the file descriptor NOW" errors into
+** SQLITE_IOERR
+**
+** Errors during initialization of locks, or file system support for locks,
+** should handle ENOLCK, ENOTSUP, EOPNOTSUPP separately.
+*/
+static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
+ assert( (sqliteIOErr == SQLITE_IOERR_LOCK) ||
+ (sqliteIOErr == SQLITE_IOERR_UNLOCK) ||
+ (sqliteIOErr == SQLITE_IOERR_RDLOCK) ||
+ (sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) );
+ switch (posixError) {
+ case EACCES:
+ case EAGAIN:
+ case ETIMEDOUT:
+ case EBUSY:
+ case EINTR:
+ case ENOLCK:
+ /* random NFS retry error, unless during file system support
+ * introspection, in which it actually means what it says */
+ return SQLITE_BUSY;
+
+ case EPERM:
+ return SQLITE_PERM;
+
+ default:
+ return sqliteIOErr;
+ }
+}
+
+
+/******************************************************************************
+****************** Begin Unique File ID Utility Used By VxWorks ***************
+**
+** On most versions of unix, we can get a unique ID for a file by concatenating
+** the device number and the inode number. But this does not work on VxWorks.
+** On VxWorks, a unique file id must be based on the canonical filename.
+**
+** A pointer to an instance of the following structure can be used as a
+** unique file ID in VxWorks. Each instance of this structure contains
+** a copy of the canonical filename. There is also a reference count.
+** The structure is reclaimed when the number of pointers to it drops to
+** zero.
+**
+** There are never very many files open at one time and lookups are not
+** a performance-critical path, so it is sufficient to put these
+** structures on a linked list.
+*/
+struct vxworksFileId {
+ struct vxworksFileId *pNext; /* Next in a list of them all */
+ int nRef; /* Number of references to this one */
+ int nName; /* Length of the zCanonicalName[] string */
+ char *zCanonicalName; /* Canonical filename */
+};
+
+#if OS_VXWORKS
+/*
+** All unique filenames are held on a linked list headed by this
+** variable:
+*/
+static struct vxworksFileId *vxworksFileList = 0;
+
+/*
+** Simplify a filename into its canonical form
+** by making the following changes:
+**
+** * removing any trailing and duplicate /
+** * convert /./ into just /
+** * convert /A/../ where A is any simple name into just /
+**
+** Changes are made in-place. Return the new name length.
+**
+** The original filename is in z[0..n-1]. Return the number of
+** characters in the simplified name.
+*/
+static int vxworksSimplifyName(char *z, int n){
+ int i, j;
+ while( n>1 && z[n-1]=='/' ){ n--; }
+ for(i=j=0; i0 && z[j-1]!='/' ){ j--; }
+ if( j>0 ){ j--; }
+ i += 2;
+ continue;
+ }
+ }
+ z[j++] = z[i];
+ }
+ z[j] = 0;
+ return j;
+}
+
+/*
+** Find a unique file ID for the given absolute pathname. Return
+** a pointer to the vxworksFileId object. This pointer is the unique
+** file ID.
+**
+** The nRef field of the vxworksFileId object is incremented before
+** the object is returned. A new vxworksFileId object is created
+** and added to the global list if necessary.
+**
+** If a memory allocation error occurs, return NULL.
+*/
+static struct vxworksFileId *vxworksFindFileId(const char *zAbsoluteName){
+ struct vxworksFileId *pNew; /* search key and new file ID */
+ struct vxworksFileId *pCandidate; /* For looping over existing file IDs */
+ int n; /* Length of zAbsoluteName string */
+
+ assert( zAbsoluteName[0]=='/' );
+ n = (int)strlen(zAbsoluteName);
+ pNew = sqlite3_malloc64( sizeof(*pNew) + (n+1) );
+ if( pNew==0 ) return 0;
+ pNew->zCanonicalName = (char*)&pNew[1];
+ memcpy(pNew->zCanonicalName, zAbsoluteName, n+1);
+ n = vxworksSimplifyName(pNew->zCanonicalName, n);
+
+ /* Search for an existing entry that matching the canonical name.
+ ** If found, increment the reference count and return a pointer to
+ ** the existing file ID.
+ */
+ unixEnterMutex();
+ for(pCandidate=vxworksFileList; pCandidate; pCandidate=pCandidate->pNext){
+ if( pCandidate->nName==n
+ && memcmp(pCandidate->zCanonicalName, pNew->zCanonicalName, n)==0
+ ){
+ sqlite3_free(pNew);
+ pCandidate->nRef++;
+ unixLeaveMutex();
+ return pCandidate;
+ }
+ }
+
+ /* No match was found. We will make a new file ID */
+ pNew->nRef = 1;
+ pNew->nName = n;
+ pNew->pNext = vxworksFileList;
+ vxworksFileList = pNew;
+ unixLeaveMutex();
+ return pNew;
+}
+
+/*
+** Decrement the reference count on a vxworksFileId object. Free
+** the object when the reference count reaches zero.
+*/
+static void vxworksReleaseFileId(struct vxworksFileId *pId){
+ unixEnterMutex();
+ assert( pId->nRef>0 );
+ pId->nRef--;
+ if( pId->nRef==0 ){
+ struct vxworksFileId **pp;
+ for(pp=&vxworksFileList; *pp && *pp!=pId; pp = &((*pp)->pNext)){}
+ assert( *pp==pId );
+ *pp = pId->pNext;
+ sqlite3_free(pId);
+ }
+ unixLeaveMutex();
+}
+#endif /* OS_VXWORKS */
+/*************** End of Unique File ID Utility Used By VxWorks ****************
+******************************************************************************/
+
+
+/******************************************************************************
+*************************** Posix Advisory Locking ****************************
+**
+** POSIX advisory locks are broken by design. ANSI STD 1003.1 (1996)
+** section 6.5.2.2 lines 483 through 490 specify that when a process
+** sets or clears a lock, that operation overrides any prior locks set
+** by the same process. It does not explicitly say so, but this implies
+** that it overrides locks set by the same process using a different
+** file descriptor. Consider this test case:
+**
+** int fd1 = open("./file1", O_RDWR|O_CREAT, 0644);
+** int fd2 = open("./file2", O_RDWR|O_CREAT, 0644);
+**
+** Suppose ./file1 and ./file2 are really the same file (because
+** one is a hard or symbolic link to the other) then if you set
+** an exclusive lock on fd1, then try to get an exclusive lock
+** on fd2, it works. I would have expected the second lock to
+** fail since there was already a lock on the file due to fd1.
+** But not so. Since both locks came from the same process, the
+** second overrides the first, even though they were on different
+** file descriptors opened on different file names.
+**
+** This means that we cannot use POSIX locks to synchronize file access
+** among competing threads of the same process. POSIX locks will work fine
+** to synchronize access for threads in separate processes, but not
+** threads within the same process.
+**
+** To work around the problem, SQLite has to manage file locks internally
+** on its own. Whenever a new database is opened, we have to find the
+** specific inode of the database file (the inode is determined by the
+** st_dev and st_ino fields of the stat structure that fstat() fills in)
+** and check for locks already existing on that inode. When locks are
+** created or removed, we have to look at our own internal record of the
+** locks to see if another thread has previously set a lock on that same
+** inode.
+**
+** (Aside: The use of inode numbers as unique IDs does not work on VxWorks.
+** For VxWorks, we have to use the alternative unique ID system based on
+** canonical filename and implemented in the previous division.)
+**
+** The sqlite3_file structure for POSIX is no longer just an integer file
+** descriptor. It is now a structure that holds the integer file
+** descriptor and a pointer to a structure that describes the internal
+** locks on the corresponding inode. There is one locking structure
+** per inode, so if the same inode is opened twice, both unixFile structures
+** point to the same locking structure. The locking structure keeps
+** a reference count (so we will know when to delete it) and a "cnt"
+** field that tells us its internal lock status. cnt==0 means the
+** file is unlocked. cnt==-1 means the file has an exclusive lock.
+** cnt>0 means there are cnt shared locks on the file.
+**
+** Any attempt to lock or unlock a file first checks the locking
+** structure. The fcntl() system call is only invoked to set a
+** POSIX lock if the internal lock structure transitions between
+** a locked and an unlocked state.
+**
+** But wait: there are yet more problems with POSIX advisory locks.
+**
+** If you close a file descriptor that points to a file that has locks,
+** all locks on that file that are owned by the current process are
+** released. To work around this problem, each unixInodeInfo object
+** maintains a count of the number of pending locks on tha inode.
+** When an attempt is made to close an unixFile, if there are
+** other unixFile open on the same inode that are holding locks, the call
+** to close() the file descriptor is deferred until all of the locks clear.
+** The unixInodeInfo structure keeps a list of file descriptors that need to
+** be closed and that list is walked (and cleared) when the last lock
+** clears.
+**
+** Yet another problem: LinuxThreads do not play well with posix locks.
+**
+** Many older versions of linux use the LinuxThreads library which is
+** not posix compliant. Under LinuxThreads, a lock created by thread
+** A cannot be modified or overridden by a different thread B.
+** Only thread A can modify the lock. Locking behavior is correct
+** if the appliation uses the newer Native Posix Thread Library (NPTL)
+** on linux - with NPTL a lock created by thread A can override locks
+** in thread B. But there is no way to know at compile-time which
+** threading library is being used. So there is no way to know at
+** compile-time whether or not thread A can override locks on thread B.
+** One has to do a run-time check to discover the behavior of the
+** current process.
+**
+** SQLite used to support LinuxThreads. But support for LinuxThreads
+** was dropped beginning with version 3.7.0. SQLite will still work with
+** LinuxThreads provided that (1) there is no more than one connection
+** per database file in the same process and (2) database connections
+** do not move across threads.
+*/
+
+/*
+** An instance of the following structure serves as the key used
+** to locate a particular unixInodeInfo object.
+*/
+struct unixFileId {
+ dev_t dev; /* Device number */
+#if OS_VXWORKS
+ struct vxworksFileId *pId; /* Unique file ID for vxworks. */
+#else
+ /* We are told that some versions of Android contain a bug that
+ ** sizes ino_t at only 32-bits instead of 64-bits. (See
+ ** https://android-review.googlesource.com/#/c/115351/3/dist/sqlite3.c)
+ ** To work around this, always allocate 64-bits for the inode number.
+ ** On small machines that only have 32-bit inodes, this wastes 4 bytes,
+ ** but that should not be a big deal. */
+ /* WAS: ino_t ino; */
+ u64 ino; /* Inode number */
+#endif
+};
+
+/*
+** An instance of the following structure is allocated for each open
+** inode. Or, on LinuxThreads, there is one of these structures for
+** each inode opened by each thread.
+**
+** A single inode can have multiple file descriptors, so each unixFile
+** structure contains a pointer to an instance of this object and this
+** object keeps a count of the number of unixFile pointing to it.
+**
+** Mutex rules:
+**
+** (1) Only the pLockMutex mutex must be held in order to read or write
+** any of the locking fields:
+** nShared, nLock, eFileLock, bProcessLock, pUnused
+**
+** (2) When nRef>0, then the following fields are unchanging and can
+** be read (but not written) without holding any mutex:
+** fileId, pLockMutex
+**
+** (3) With the exceptions above, all the fields may only be read
+** or written while holding the global unixBigLock mutex.
+**
+** Deadlock prevention: The global unixBigLock mutex may not
+** be acquired while holding the pLockMutex mutex. If both unixBigLock
+** and pLockMutex are needed, then unixBigLock must be acquired first.
+*/
+struct unixInodeInfo {
+ struct unixFileId fileId; /* The lookup key */
+ sqlite3_mutex *pLockMutex; /* Hold this mutex for... */
+ int nShared; /* Number of SHARED locks held */
+ int nLock; /* Number of outstanding file locks */
+ unsigned char eFileLock; /* One of SHARED_LOCK, RESERVED_LOCK etc. */
+ unsigned char bProcessLock; /* An exclusive process lock is held */
+ UnixUnusedFd *pUnused; /* Unused file descriptors to close */
+ int nRef; /* Number of pointers to this structure */
+ unixShmNode *pShmNode; /* Shared memory associated with this inode */
+ unixInodeInfo *pNext; /* List of all unixInodeInfo objects */
+ unixInodeInfo *pPrev; /* .... doubly linked */
+#if SQLITE_ENABLE_LOCKING_STYLE
+ unsigned long long sharedByte; /* for AFP simulated shared lock */
+#endif
+#if OS_VXWORKS
+ sem_t *pSem; /* Named POSIX semaphore */
+ char aSemName[MAX_PATHNAME+2]; /* Name of that semaphore */
+#endif
+};
+
+/*
+** A lists of all unixInodeInfo objects.
+*/
+static unixInodeInfo *inodeList = 0; /* All unixInodeInfo objects */
+
+#ifdef SQLITE_DEBUG
+/*
+** True if the inode mutex is held, or not. Used only within assert()
+** to help verify correct mutex usage.
+*/
+int unixFileMutexHeld(unixFile *pFile){
+ assert( pFile->pInode );
+ return sqlite3_mutex_held(pFile->pInode->pLockMutex);
+}
+int unixFileMutexNotheld(unixFile *pFile){
+ assert( pFile->pInode );
+ return sqlite3_mutex_notheld(pFile->pInode->pLockMutex);
+}
+#endif
+
+/*
+**
+** This function - unixLogErrorAtLine(), is only ever called via the macro
+** unixLogError().
+**
+** It is invoked after an error occurs in an OS function and errno has been
+** set. It logs a message using sqlite3_log() containing the current value of
+** errno and, if possible, the human-readable equivalent from strerror() or
+** strerror_r().
+**
+** The first argument passed to the macro should be the error code that
+** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN).
+** The two subsequent arguments should be the name of the OS function that
+** failed (e.g. "unlink", "open") and the associated file-system path,
+** if any.
+*/
+#define unixLogError(a,b,c) unixLogErrorAtLine(a,b,c,__LINE__)
+static int unixLogErrorAtLine(
+ int errcode, /* SQLite error code */
+ const char *zFunc, /* Name of OS function that failed */
+ const char *zPath, /* File path associated with error */
+ int iLine /* Source line number where error occurred */
+){
+ char *zErr; /* Message from strerror() or equivalent */
+ int iErrno = errno; /* Saved syscall error number */
+
+ /* If this is not a threadsafe build (SQLITE_THREADSAFE==0), then use
+ ** the strerror() function to obtain the human-readable error message
+ ** equivalent to errno. Otherwise, use strerror_r().
+ */
+#if SQLITE_THREADSAFE && defined(HAVE_STRERROR_R)
+ char aErr[80];
+ memset(aErr, 0, sizeof(aErr));
+ zErr = aErr;
+
+ /* If STRERROR_R_CHAR_P (set by autoconf scripts) or __USE_GNU is defined,
+ ** assume that the system provides the GNU version of strerror_r() that
+ ** returns a pointer to a buffer containing the error message. That pointer
+ ** may point to aErr[], or it may point to some static storage somewhere.
+ ** Otherwise, assume that the system provides the POSIX version of
+ ** strerror_r(), which always writes an error message into aErr[].
+ **
+ ** If the code incorrectly assumes that it is the POSIX version that is
+ ** available, the error message will often be an empty string. Not a
+ ** huge problem. Incorrectly concluding that the GNU version is available
+ ** could lead to a segfault though.
+ */
+#if defined(STRERROR_R_CHAR_P) || defined(__USE_GNU)
+ zErr =
+# endif
+ strerror_r(iErrno, aErr, sizeof(aErr)-1);
+
+#elif SQLITE_THREADSAFE
+ /* This is a threadsafe build, but strerror_r() is not available. */
+ zErr = "";
+#else
+ /* Non-threadsafe build, use strerror(). */
+ zErr = strerror(iErrno);
+#endif
+
+ if( zPath==0 ) zPath = "";
+ sqlite3_log(errcode,
+ "os_unix.c:%d: (%d) %s(%s) - %s",
+ iLine, iErrno, zFunc, zPath, zErr
+ );
+
+ return errcode;
+}
+
+/*
+** Close a file descriptor.
+**
+** We assume that close() almost always works, since it is only in a
+** very sick application or on a very sick platform that it might fail.
+** If it does fail, simply leak the file descriptor, but do log the
+** error.
+**
+** Note that it is not safe to retry close() after EINTR since the
+** file descriptor might have already been reused by another thread.
+** So we don't even try to recover from an EINTR. Just log the error
+** and move on.
+*/
+static void robust_close(unixFile *pFile, int h, int lineno){
+ if( osClose(h) ){
+ unixLogErrorAtLine(SQLITE_IOERR_CLOSE, "close",
+ pFile ? pFile->zPath : 0, lineno);
+ }
+}
+
+/*
+** Set the pFile->lastErrno. Do this in a subroutine as that provides
+** a convenient place to set a breakpoint.
+*/
+static void storeLastErrno(unixFile *pFile, int error){
+ pFile->lastErrno = error;
+}
+
+/*
+** Close all file descriptors accumuated in the unixInodeInfo->pUnused list.
+*/
+static void closePendingFds(unixFile *pFile){
+ unixInodeInfo *pInode = pFile->pInode;
+ UnixUnusedFd *p;
+ UnixUnusedFd *pNext;
+ assert( unixFileMutexHeld(pFile) );
+ for(p=pInode->pUnused; p; p=pNext){
+ pNext = p->pNext;
+ robust_close(pFile, p->fd, __LINE__);
+ sqlite3_free(p);
+ }
+ pInode->pUnused = 0;
+}
+
+/*
+** Release a unixInodeInfo structure previously allocated by findInodeInfo().
+**
+** The mutex entered using the unixEnterMutex() function must be held
+** when this function is called.
+*/
+static void releaseInodeInfo(unixFile *pFile){
+ unixInodeInfo *pInode = pFile->pInode;
+ assert( unixMutexHeld() );
+ assert( unixFileMutexNotheld(pFile) );
+ if( ALWAYS(pInode) ){
+ pInode->nRef--;
+ if( pInode->nRef==0 ){
+ assert( pInode->pShmNode==0 );
+ sqlite3_mutex_enter(pInode->pLockMutex);
+ closePendingFds(pFile);
+ sqlite3_mutex_leave(pInode->pLockMutex);
+ if( pInode->pPrev ){
+ assert( pInode->pPrev->pNext==pInode );
+ pInode->pPrev->pNext = pInode->pNext;
+ }else{
+ assert( inodeList==pInode );
+ inodeList = pInode->pNext;
+ }
+ if( pInode->pNext ){
+ assert( pInode->pNext->pPrev==pInode );
+ pInode->pNext->pPrev = pInode->pPrev;
+ }
+ sqlite3_mutex_free(pInode->pLockMutex);
+ sqlite3_free(pInode);
+ }
+ }
+}
+
+/*
+** Given a file descriptor, locate the unixInodeInfo object that
+** describes that file descriptor. Create a new one if necessary. The
+** return value might be uninitialized if an error occurs.
+**
+** The mutex entered using the unixEnterMutex() function must be held
+** when this function is called.
+**
+** Return an appropriate error code.
+*/
+static int findInodeInfo(
+ unixFile *pFile, /* Unix file with file desc used in the key */
+ unixInodeInfo **ppInode /* Return the unixInodeInfo object here */
+){
+ int rc; /* System call return code */
+ int fd; /* The file descriptor for pFile */
+ struct unixFileId fileId; /* Lookup key for the unixInodeInfo */
+ struct stat statbuf; /* Low-level file information */
+ unixInodeInfo *pInode = 0; /* Candidate unixInodeInfo object */
+
+ assert( unixMutexHeld() );
+
+ /* Get low-level information about the file that we can used to
+ ** create a unique name for the file.
+ */
+ fd = pFile->h;
+ rc = osFstat(fd, &statbuf);
+ if( rc!=0 ){
+ storeLastErrno(pFile, errno);
+#if defined(EOVERFLOW) && defined(SQLITE_DISABLE_LFS)
+ if( pFile->lastErrno==EOVERFLOW ) return SQLITE_NOLFS;
+#endif
+ return SQLITE_IOERR;
+ }
+
+#ifdef __APPLE__
+ /* On OS X on an msdos filesystem, the inode number is reported
+ ** incorrectly for zero-size files. See ticket #3260. To work
+ ** around this problem (we consider it a bug in OS X, not SQLite)
+ ** we always increase the file size to 1 by writing a single byte
+ ** prior to accessing the inode number. The one byte written is
+ ** an ASCII 'S' character which also happens to be the first byte
+ ** in the header of every SQLite database. In this way, if there
+ ** is a race condition such that another thread has already populated
+ ** the first page of the database, no damage is done.
+ */
+ if( statbuf.st_size==0 && (pFile->fsFlags & SQLITE_FSFLAGS_IS_MSDOS)!=0 ){
+ do{ rc = osWrite(fd, "S", 1); }while( rc<0 && errno==EINTR );
+ if( rc!=1 ){
+ storeLastErrno(pFile, errno);
+ return SQLITE_IOERR;
+ }
+ rc = osFstat(fd, &statbuf);
+ if( rc!=0 ){
+ storeLastErrno(pFile, errno);
+ return SQLITE_IOERR;
+ }
+ }
+#endif
+
+ memset(&fileId, 0, sizeof(fileId));
+ fileId.dev = statbuf.st_dev;
+#if OS_VXWORKS
+ fileId.pId = pFile->pId;
+#else
+ fileId.ino = (u64)statbuf.st_ino;
+#endif
+ pInode = inodeList;
+ while( pInode && memcmp(&fileId, &pInode->fileId, sizeof(fileId)) ){
+ pInode = pInode->pNext;
+ }
+ if( pInode==0 ){
+ pInode = sqlite3_malloc64( sizeof(*pInode) );
+ if( pInode==0 ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ memset(pInode, 0, sizeof(*pInode));
+ memcpy(&pInode->fileId, &fileId, sizeof(fileId));
+ if( sqlite3GlobalConfig.bCoreMutex ){
+ pInode->pLockMutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
+ if( pInode->pLockMutex==0 ){
+ sqlite3_free(pInode);
+ return SQLITE_NOMEM_BKPT;
+ }
+ }
+ pInode->nRef = 1;
+ pInode->pNext = inodeList;
+ pInode->pPrev = 0;
+ if( inodeList ) inodeList->pPrev = pInode;
+ inodeList = pInode;
+ }else{
+ pInode->nRef++;
+ }
+ *ppInode = pInode;
+ return SQLITE_OK;
+}
+
+/*
+** Return TRUE if pFile has been renamed or unlinked since it was first opened.
+*/
+static int fileHasMoved(unixFile *pFile){
+#if OS_VXWORKS
+ return pFile->pInode!=0 && pFile->pId!=pFile->pInode->fileId.pId;
+#else
+ struct stat buf;
+ return pFile->pInode!=0 &&
+ (osStat(pFile->zPath, &buf)!=0
+ || (u64)buf.st_ino!=pFile->pInode->fileId.ino);
+#endif
+}
+
+
+/*
+** Check a unixFile that is a database. Verify the following:
+**
+** (1) There is exactly one hard link on the file
+** (2) The file is not a symbolic link
+** (3) The file has not been renamed or unlinked
+**
+** Issue sqlite3_log(SQLITE_WARNING,...) messages if anything is not right.
+*/
+static void verifyDbFile(unixFile *pFile){
+ struct stat buf;
+ int rc;
+
+ /* These verifications occurs for the main database only */
+ if( pFile->ctrlFlags & UNIXFILE_NOLOCK ) return;
+
+ rc = osFstat(pFile->h, &buf);
+ if( rc!=0 ){
+ sqlite3_log(SQLITE_WARNING, "cannot fstat db file %s", pFile->zPath);
+ return;
+ }
+ if( buf.st_nlink==0 ){
+ sqlite3_log(SQLITE_WARNING, "file unlinked while open: %s", pFile->zPath);
+ return;
+ }
+ if( buf.st_nlink>1 ){
+ sqlite3_log(SQLITE_WARNING, "multiple links to file: %s", pFile->zPath);
+ return;
+ }
+ if( fileHasMoved(pFile) ){
+ sqlite3_log(SQLITE_WARNING, "file renamed while open: %s", pFile->zPath);
+ return;
+ }
+}
+
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int unixCheckReservedLock(sqlite3_file *id, int *pResOut){
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+ assert( pFile->eFileLock<=SHARED_LOCK );
+ sqlite3_mutex_enter(pFile->pInode->pLockMutex);
+
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->pInode->eFileLock>SHARED_LOCK ){
+ reserved = 1;
+ }
+
+ /* Otherwise see if some other process holds it.
+ */
+#ifndef __DJGPP__
+ if( !reserved && !pFile->pInode->bProcessLock ){
+ struct flock lock;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = RESERVED_BYTE;
+ lock.l_len = 1;
+ lock.l_type = F_WRLCK;
+ if( osFcntl(pFile->h, F_GETLK, &lock) ){
+ rc = SQLITE_IOERR_CHECKRESERVEDLOCK;
+ storeLastErrno(pFile, errno);
+ } else if( lock.l_type!=F_UNLCK ){
+ reserved = 1;
+ }
+ }
+#endif
+
+ sqlite3_mutex_leave(pFile->pInode->pLockMutex);
+ OSTRACE(("TEST WR-LOCK %d %d %d (unix)\n", pFile->h, rc, reserved));
+
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Set a posix-advisory-lock.
+**
+** There are two versions of this routine. If compiled with
+** SQLITE_ENABLE_SETLK_TIMEOUT then the routine has an extra parameter
+** which is a pointer to a unixFile. If the unixFile->iBusyTimeout
+** value is set, then it is the number of milliseconds to wait before
+** failing the lock. The iBusyTimeout value is always reset back to
+** zero on each call.
+**
+** If SQLITE_ENABLE_SETLK_TIMEOUT is not defined, then do a non-blocking
+** attempt to set the lock.
+*/
+#ifndef SQLITE_ENABLE_SETLK_TIMEOUT
+# define osSetPosixAdvisoryLock(h,x,t) osFcntl(h,F_SETLK,x)
+#else
+static int osSetPosixAdvisoryLock(
+ int h, /* The file descriptor on which to take the lock */
+ struct flock *pLock, /* The description of the lock */
+ unixFile *pFile /* Structure holding timeout value */
+){
+ int rc = osFcntl(h,F_SETLK,pLock);
+ while( rc<0 && pFile->iBusyTimeout>0 ){
+ /* On systems that support some kind of blocking file lock with a timeout,
+ ** make appropriate changes here to invoke that blocking file lock. On
+ ** generic posix, however, there is no such API. So we simply try the
+ ** lock once every millisecond until either the timeout expires, or until
+ ** the lock is obtained. */
+ usleep(1000);
+ rc = osFcntl(h,F_SETLK,pLock);
+ pFile->iBusyTimeout--;
+ }
+ return rc;
+}
+#endif /* SQLITE_ENABLE_SETLK_TIMEOUT */
+
+
+/*
+** Attempt to set a system-lock on the file pFile. The lock is
+** described by pLock.
+**
+** If the pFile was opened read/write from unix-excl, then the only lock
+** ever obtained is an exclusive lock, and it is obtained exactly once
+** the first time any lock is attempted. All subsequent system locking
+** operations become no-ops. Locking operations still happen internally,
+** in order to coordinate access between separate database connections
+** within this process, but all of that is handled in memory and the
+** operating system does not participate.
+**
+** This function is a pass-through to fcntl(F_SETLK) if pFile is using
+** any VFS other than "unix-excl" or if pFile is opened on "unix-excl"
+** and is read-only.
+**
+** Zero is returned if the call completes successfully, or -1 if a call
+** to fcntl() fails. In this case, errno is set appropriately (by fcntl()).
+*/
+static int unixFileLock(unixFile *pFile, struct flock *pLock){
+ int rc;
+ unixInodeInfo *pInode = pFile->pInode;
+ assert( pInode!=0 );
+ assert( sqlite3_mutex_held(pInode->pLockMutex) );
+ if( (pFile->ctrlFlags & (UNIXFILE_EXCL|UNIXFILE_RDONLY))==UNIXFILE_EXCL ){
+ if( pInode->bProcessLock==0 ){
+ struct flock lock;
+ assert( pInode->nLock==0 );
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = SHARED_SIZE;
+ lock.l_type = F_WRLCK;
+ rc = osSetPosixAdvisoryLock(pFile->h, &lock, pFile);
+ if( rc<0 ) return rc;
+ pInode->bProcessLock = 1;
+ pInode->nLock++;
+ }else{
+ rc = 0;
+ }
+ }else{
+ rc = osSetPosixAdvisoryLock(pFile->h, pLock, pFile);
+ }
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int unixLock(sqlite3_file *id, int eFileLock){
+ /* The following describes the implementation of the various locks and
+ ** lock transitions in terms of the POSIX advisory shared and exclusive
+ ** lock primitives (called read-locks and write-locks below, to avoid
+ ** confusion with SQLite lock names). The algorithms are complicated
+ ** slightly in order to be compatible with Windows95 systems simultaneously
+ ** accessing the same database file, in case that is ever required.
+ **
+ ** Symbols defined in os.h indentify the 'pending byte' and the 'reserved
+ ** byte', each single bytes at well known offsets, and the 'shared byte
+ ** range', a range of 510 bytes at a well known offset.
+ **
+ ** To obtain a SHARED lock, a read-lock is obtained on the 'pending
+ ** byte'. If this is successful, 'shared byte range' is read-locked
+ ** and the lock on the 'pending byte' released. (Legacy note: When
+ ** SQLite was first developed, Windows95 systems were still very common,
+ ** and Widnows95 lacks a shared-lock capability. So on Windows95, a
+ ** single randomly selected by from the 'shared byte range' is locked.
+ ** Windows95 is now pretty much extinct, but this work-around for the
+ ** lack of shared-locks on Windows95 lives on, for backwards
+ ** compatibility.)
+ **
+ ** A process may only obtain a RESERVED lock after it has a SHARED lock.
+ ** A RESERVED lock is implemented by grabbing a write-lock on the
+ ** 'reserved byte'.
+ **
+ ** A process may only obtain a PENDING lock after it has obtained a
+ ** SHARED lock. A PENDING lock is implemented by obtaining a write-lock
+ ** on the 'pending byte'. This ensures that no new SHARED locks can be
+ ** obtained, but existing SHARED locks are allowed to persist. A process
+ ** does not have to obtain a RESERVED lock on the way to a PENDING lock.
+ ** This property is used by the algorithm for rolling back a journal file
+ ** after a crash.
+ **
+ ** An EXCLUSIVE lock, obtained after a PENDING lock is held, is
+ ** implemented by obtaining a write-lock on the entire 'shared byte
+ ** range'. Since all other locks require a read-lock on one of the bytes
+ ** within this range, this ensures that no other locks are held on the
+ ** database.
+ */
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+ unixInodeInfo *pInode;
+ struct flock lock;
+ int tErrno = 0;
+
+ assert( pFile );
+ OSTRACE(("LOCK %d %s was %s(%s,%d) pid=%d (unix)\n", pFile->h,
+ azFileLock(eFileLock), azFileLock(pFile->eFileLock),
+ azFileLock(pFile->pInode->eFileLock), pFile->pInode->nShared,
+ osGetpid(0)));
+
+ /* If there is already a lock of this type or more restrictive on the
+ ** unixFile, do nothing. Don't use the end_lock: exit path, as
+ ** unixEnterMutex() hasn't been called yet.
+ */
+ if( pFile->eFileLock>=eFileLock ){
+ OSTRACE(("LOCK %d %s ok (already held) (unix)\n", pFile->h,
+ azFileLock(eFileLock)));
+ return SQLITE_OK;
+ }
+
+ /* Make sure the locking sequence is correct.
+ ** (1) We never move from unlocked to anything higher than shared lock.
+ ** (2) SQLite never explicitly requests a pendig lock.
+ ** (3) A shared lock is always held when a reserve lock is requested.
+ */
+ assert( pFile->eFileLock!=NO_LOCK || eFileLock==SHARED_LOCK );
+ assert( eFileLock!=PENDING_LOCK );
+ assert( eFileLock!=RESERVED_LOCK || pFile->eFileLock==SHARED_LOCK );
+
+ /* This mutex is needed because pFile->pInode is shared across threads
+ */
+ pInode = pFile->pInode;
+ sqlite3_mutex_enter(pInode->pLockMutex);
+
+ /* If some thread using this PID has a lock via a different unixFile*
+ ** handle that precludes the requested lock, return BUSY.
+ */
+ if( (pFile->eFileLock!=pInode->eFileLock &&
+ (pInode->eFileLock>=PENDING_LOCK || eFileLock>SHARED_LOCK))
+ ){
+ rc = SQLITE_BUSY;
+ goto end_lock;
+ }
+
+ /* If a SHARED lock is requested, and some thread using this PID already
+ ** has a SHARED or RESERVED lock, then increment reference counts and
+ ** return SQLITE_OK.
+ */
+ if( eFileLock==SHARED_LOCK &&
+ (pInode->eFileLock==SHARED_LOCK || pInode->eFileLock==RESERVED_LOCK) ){
+ assert( eFileLock==SHARED_LOCK );
+ assert( pFile->eFileLock==0 );
+ assert( pInode->nShared>0 );
+ pFile->eFileLock = SHARED_LOCK;
+ pInode->nShared++;
+ pInode->nLock++;
+ goto end_lock;
+ }
+
+
+ /* A PENDING lock is needed before acquiring a SHARED lock and before
+ ** acquiring an EXCLUSIVE lock. For the SHARED lock, the PENDING will
+ ** be released.
+ */
+ lock.l_len = 1L;
+ lock.l_whence = SEEK_SET;
+ if( eFileLock==SHARED_LOCK
+ || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLocknShared==0 );
+ assert( pInode->eFileLock==0 );
+ assert( rc==SQLITE_OK );
+
+ /* Now get the read-lock */
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = SHARED_SIZE;
+ if( unixFileLock(pFile, &lock) ){
+ tErrno = errno;
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ }
+
+ /* Drop the temporary PENDING lock */
+ lock.l_start = PENDING_BYTE;
+ lock.l_len = 1L;
+ lock.l_type = F_UNLCK;
+ if( unixFileLock(pFile, &lock) && rc==SQLITE_OK ){
+ /* This could happen with a network mount */
+ tErrno = errno;
+ rc = SQLITE_IOERR_UNLOCK;
+ }
+
+ if( rc ){
+ if( rc!=SQLITE_BUSY ){
+ storeLastErrno(pFile, tErrno);
+ }
+ goto end_lock;
+ }else{
+ pFile->eFileLock = SHARED_LOCK;
+ pInode->nLock++;
+ pInode->nShared = 1;
+ }
+ }else if( eFileLock==EXCLUSIVE_LOCK && pInode->nShared>1 ){
+ /* We are trying for an exclusive lock but another thread in this
+ ** same process is still holding a shared lock. */
+ rc = SQLITE_BUSY;
+ }else{
+ /* The request was for a RESERVED or EXCLUSIVE lock. It is
+ ** assumed that there is a SHARED or greater lock on the file
+ ** already.
+ */
+ assert( 0!=pFile->eFileLock );
+ lock.l_type = F_WRLCK;
+
+ assert( eFileLock==RESERVED_LOCK || eFileLock==EXCLUSIVE_LOCK );
+ if( eFileLock==RESERVED_LOCK ){
+ lock.l_start = RESERVED_BYTE;
+ lock.l_len = 1L;
+ }else{
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = SHARED_SIZE;
+ }
+
+ if( unixFileLock(pFile, &lock) ){
+ tErrno = errno;
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ if( rc!=SQLITE_BUSY ){
+ storeLastErrno(pFile, tErrno);
+ }
+ }
+ }
+
+
+#ifdef SQLITE_DEBUG
+ /* Set up the transaction-counter change checking flags when
+ ** transitioning from a SHARED to a RESERVED lock. The change
+ ** from SHARED to RESERVED marks the beginning of a normal
+ ** write operation (not a hot journal rollback).
+ */
+ if( rc==SQLITE_OK
+ && pFile->eFileLock<=SHARED_LOCK
+ && eFileLock==RESERVED_LOCK
+ ){
+ pFile->transCntrChng = 0;
+ pFile->dbUpdate = 0;
+ pFile->inNormalWrite = 1;
+ }
+#endif
+
+
+ if( rc==SQLITE_OK ){
+ pFile->eFileLock = eFileLock;
+ pInode->eFileLock = eFileLock;
+ }else if( eFileLock==EXCLUSIVE_LOCK ){
+ pFile->eFileLock = PENDING_LOCK;
+ pInode->eFileLock = PENDING_LOCK;
+ }
+
+end_lock:
+ sqlite3_mutex_leave(pInode->pLockMutex);
+ OSTRACE(("LOCK %d %s %s (unix)\n", pFile->h, azFileLock(eFileLock),
+ rc==SQLITE_OK ? "ok" : "failed"));
+ return rc;
+}
+
+/*
+** Add the file descriptor used by file handle pFile to the corresponding
+** pUnused list.
+*/
+static void setPendingFd(unixFile *pFile){
+ unixInodeInfo *pInode = pFile->pInode;
+ UnixUnusedFd *p = pFile->pPreallocatedUnused;
+ assert( unixFileMutexHeld(pFile) );
+ p->pNext = pInode->pUnused;
+ pInode->pUnused = p;
+ pFile->h = -1;
+ pFile->pPreallocatedUnused = 0;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+**
+** If handleNFSUnlock is true, then on downgrading an EXCLUSIVE_LOCK to SHARED
+** the byte range is divided into 2 parts and the first part is unlocked then
+** set to a read lock, then the other part is simply unlocked. This works
+** around a bug in BSD NFS lockd (also seen on MacOSX 10.3+) that fails to
+** remove the write lock on a region when a read lock is set.
+*/
+static int posixUnlock(sqlite3_file *id, int eFileLock, int handleNFSUnlock){
+ unixFile *pFile = (unixFile*)id;
+ unixInodeInfo *pInode;
+ struct flock lock;
+ int rc = SQLITE_OK;
+
+ assert( pFile );
+ OSTRACE(("UNLOCK %d %d was %d(%d,%d) pid=%d (unix)\n", pFile->h, eFileLock,
+ pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
+ osGetpid(0)));
+
+ assert( eFileLock<=SHARED_LOCK );
+ if( pFile->eFileLock<=eFileLock ){
+ return SQLITE_OK;
+ }
+ pInode = pFile->pInode;
+ sqlite3_mutex_enter(pInode->pLockMutex);
+ assert( pInode->nShared!=0 );
+ if( pFile->eFileLock>SHARED_LOCK ){
+ assert( pInode->eFileLock==pFile->eFileLock );
+
+#ifdef SQLITE_DEBUG
+ /* When reducing a lock such that other processes can start
+ ** reading the database file again, make sure that the
+ ** transaction counter was updated if any part of the database
+ ** file changed. If the transaction counter is not updated,
+ ** other connections to the same file might not realize that
+ ** the file has changed and hence might not know to flush their
+ ** cache. The use of a stale cache can lead to database corruption.
+ */
+ pFile->inNormalWrite = 0;
+#endif
+
+ /* downgrading to a shared lock on NFS involves clearing the write lock
+ ** before establishing the readlock - to avoid a race condition we downgrade
+ ** the lock in 2 blocks, so that part of the range will be covered by a
+ ** write lock until the rest is covered by a read lock:
+ ** 1: [WWWWW]
+ ** 2: [....W]
+ ** 3: [RRRRW]
+ ** 4: [RRRR.]
+ */
+ if( eFileLock==SHARED_LOCK ){
+#if !defined(__APPLE__) || !SQLITE_ENABLE_LOCKING_STYLE
+ (void)handleNFSUnlock;
+ assert( handleNFSUnlock==0 );
+#endif
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+ if( handleNFSUnlock ){
+ int tErrno; /* Error code from system call errors */
+ off_t divSize = SHARED_SIZE - 1;
+
+ lock.l_type = F_UNLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = divSize;
+ if( unixFileLock(pFile, &lock)==(-1) ){
+ tErrno = errno;
+ rc = SQLITE_IOERR_UNLOCK;
+ storeLastErrno(pFile, tErrno);
+ goto end_unlock;
+ }
+ lock.l_type = F_RDLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = divSize;
+ if( unixFileLock(pFile, &lock)==(-1) ){
+ tErrno = errno;
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_RDLOCK);
+ if( IS_LOCK_ERROR(rc) ){
+ storeLastErrno(pFile, tErrno);
+ }
+ goto end_unlock;
+ }
+ lock.l_type = F_UNLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST+divSize;
+ lock.l_len = SHARED_SIZE-divSize;
+ if( unixFileLock(pFile, &lock)==(-1) ){
+ tErrno = errno;
+ rc = SQLITE_IOERR_UNLOCK;
+ storeLastErrno(pFile, tErrno);
+ goto end_unlock;
+ }
+ }else
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+ {
+ lock.l_type = F_RDLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = SHARED_SIZE;
+ if( unixFileLock(pFile, &lock) ){
+ /* In theory, the call to unixFileLock() cannot fail because another
+ ** process is holding an incompatible lock. If it does, this
+ ** indicates that the other process is not following the locking
+ ** protocol. If this happens, return SQLITE_IOERR_RDLOCK. Returning
+ ** SQLITE_BUSY would confuse the upper layer (in practice it causes
+ ** an assert to fail). */
+ rc = SQLITE_IOERR_RDLOCK;
+ storeLastErrno(pFile, errno);
+ goto end_unlock;
+ }
+ }
+ }
+ lock.l_type = F_UNLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = PENDING_BYTE;
+ lock.l_len = 2L; assert( PENDING_BYTE+1==RESERVED_BYTE );
+ if( unixFileLock(pFile, &lock)==0 ){
+ pInode->eFileLock = SHARED_LOCK;
+ }else{
+ rc = SQLITE_IOERR_UNLOCK;
+ storeLastErrno(pFile, errno);
+ goto end_unlock;
+ }
+ }
+ if( eFileLock==NO_LOCK ){
+ /* Decrement the shared lock counter. Release the lock using an
+ ** OS call only when all threads in this same process have released
+ ** the lock.
+ */
+ pInode->nShared--;
+ if( pInode->nShared==0 ){
+ lock.l_type = F_UNLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = lock.l_len = 0L;
+ if( unixFileLock(pFile, &lock)==0 ){
+ pInode->eFileLock = NO_LOCK;
+ }else{
+ rc = SQLITE_IOERR_UNLOCK;
+ storeLastErrno(pFile, errno);
+ pInode->eFileLock = NO_LOCK;
+ pFile->eFileLock = NO_LOCK;
+ }
+ }
+
+ /* Decrement the count of locks against this same file. When the
+ ** count reaches zero, close any other file descriptors whose close
+ ** was deferred because of outstanding locks.
+ */
+ pInode->nLock--;
+ assert( pInode->nLock>=0 );
+ if( pInode->nLock==0 ) closePendingFds(pFile);
+ }
+
+end_unlock:
+ sqlite3_mutex_leave(pInode->pLockMutex);
+ if( rc==SQLITE_OK ){
+ pFile->eFileLock = eFileLock;
+ }
+ return rc;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int unixUnlock(sqlite3_file *id, int eFileLock){
+#if SQLITE_MAX_MMAP_SIZE>0
+ assert( eFileLock==SHARED_LOCK || ((unixFile *)id)->nFetchOut==0 );
+#endif
+ return posixUnlock(id, eFileLock, 0);
+}
+
+#if SQLITE_MAX_MMAP_SIZE>0
+static int unixMapfile(unixFile *pFd, i64 nByte);
+static void unixUnmapfile(unixFile *pFd);
+#endif
+
+/*
+** This function performs the parts of the "close file" operation
+** common to all locking schemes. It closes the directory and file
+** handles, if they are valid, and sets all fields of the unixFile
+** structure to 0.
+**
+** It is *not* necessary to hold the mutex when this routine is called,
+** even on VxWorks. A mutex will be acquired on VxWorks by the
+** vxworksReleaseFileId() routine.
+*/
+static int closeUnixFile(sqlite3_file *id){
+ unixFile *pFile = (unixFile*)id;
+#if SQLITE_MAX_MMAP_SIZE>0
+ unixUnmapfile(pFile);
+#endif
+ if( pFile->h>=0 ){
+ robust_close(pFile, pFile->h, __LINE__);
+ pFile->h = -1;
+ }
+#if OS_VXWORKS
+ if( pFile->pId ){
+ if( pFile->ctrlFlags & UNIXFILE_DELETE ){
+ osUnlink(pFile->pId->zCanonicalName);
+ }
+ vxworksReleaseFileId(pFile->pId);
+ pFile->pId = 0;
+ }
+#endif
+#ifdef SQLITE_UNLINK_AFTER_CLOSE
+ if( pFile->ctrlFlags & UNIXFILE_DELETE ){
+ osUnlink(pFile->zPath);
+ sqlite3_free(*(char**)&pFile->zPath);
+ pFile->zPath = 0;
+ }
+#endif
+ OSTRACE(("CLOSE %-3d\n", pFile->h));
+ OpenCounter(-1);
+ sqlite3_free(pFile->pPreallocatedUnused);
+ memset(pFile, 0, sizeof(unixFile));
+ return SQLITE_OK;
+}
+
+/*
+** Close a file.
+*/
+static int unixClose(sqlite3_file *id){
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile *)id;
+ unixInodeInfo *pInode = pFile->pInode;
+
+ assert( pInode!=0 );
+ verifyDbFile(pFile);
+ unixUnlock(id, NO_LOCK);
+ assert( unixFileMutexNotheld(pFile) );
+ unixEnterMutex();
+
+ /* unixFile.pInode is always valid here. Otherwise, a different close
+ ** routine (e.g. nolockClose()) would be called instead.
+ */
+ assert( pFile->pInode->nLock>0 || pFile->pInode->bProcessLock==0 );
+ sqlite3_mutex_enter(pInode->pLockMutex);
+ if( pInode->nLock ){
+ /* If there are outstanding locks, do not actually close the file just
+ ** yet because that would clear those locks. Instead, add the file
+ ** descriptor to pInode->pUnused list. It will be automatically closed
+ ** when the last lock is cleared.
+ */
+ setPendingFd(pFile);
+ }
+ sqlite3_mutex_leave(pInode->pLockMutex);
+ releaseInodeInfo(pFile);
+ rc = closeUnixFile(id);
+ unixLeaveMutex();
+ return rc;
+}
+
+/************** End of the posix advisory lock implementation *****************
+******************************************************************************/
+
+/******************************************************************************
+****************************** No-op Locking **********************************
+**
+** Of the various locking implementations available, this is by far the
+** simplest: locking is ignored. No attempt is made to lock the database
+** file for reading or writing.
+**
+** This locking mode is appropriate for use on read-only databases
+** (ex: databases that are burned into CD-ROM, for example.) It can
+** also be used if the application employs some external mechanism to
+** prevent simultaneous access of the same database by two or more
+** database connections. But there is a serious risk of database
+** corruption if this locking mode is used in situations where multiple
+** database connections are accessing the same database file at the same
+** time and one or more of those connections are writing.
+*/
+
+static int nolockCheckReservedLock(sqlite3_file *NotUsed, int *pResOut){
+ UNUSED_PARAMETER(NotUsed);
+ *pResOut = 0;
+ return SQLITE_OK;
+}
+static int nolockLock(sqlite3_file *NotUsed, int NotUsed2){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ return SQLITE_OK;
+}
+static int nolockUnlock(sqlite3_file *NotUsed, int NotUsed2){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ return SQLITE_OK;
+}
+
+/*
+** Close the file.
+*/
+static int nolockClose(sqlite3_file *id) {
+ return closeUnixFile(id);
+}
+
+/******************* End of the no-op lock implementation *********************
+******************************************************************************/
+
+/******************************************************************************
+************************* Begin dot-file Locking ******************************
+**
+** The dotfile locking implementation uses the existence of separate lock
+** files (really a directory) to control access to the database. This works
+** on just about every filesystem imaginable. But there are serious downsides:
+**
+** (1) There is zero concurrency. A single reader blocks all other
+** connections from reading or writing the database.
+**
+** (2) An application crash or power loss can leave stale lock files
+** sitting around that need to be cleared manually.
+**
+** Nevertheless, a dotlock is an appropriate locking mode for use if no
+** other locking strategy is available.
+**
+** Dotfile locking works by creating a subdirectory in the same directory as
+** the database and with the same name but with a ".lock" extension added.
+** The existence of a lock directory implies an EXCLUSIVE lock. All other
+** lock types (SHARED, RESERVED, PENDING) are mapped into EXCLUSIVE.
+*/
+
+/*
+** The file suffix added to the data base filename in order to create the
+** lock directory.
+*/
+#define DOTLOCK_SUFFIX ".lock"
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+**
+** In dotfile locking, either a lock exists or it does not. So in this
+** variation of CheckReservedLock(), *pResOut is set to true if any lock
+** is held on the file and false if the file is unlocked.
+*/
+static int dotlockCheckReservedLock(sqlite3_file *id, int *pResOut) {
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+ reserved = osAccess((const char*)pFile->lockingContext, 0)==0;
+ OSTRACE(("TEST WR-LOCK %d %d %d (dotlock)\n", pFile->h, rc, reserved));
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+**
+** With dotfile locking, we really only support state (4): EXCLUSIVE.
+** But we track the other locking levels internally.
+*/
+static int dotlockLock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ char *zLockFile = (char *)pFile->lockingContext;
+ int rc = SQLITE_OK;
+
+
+ /* If we have any lock, then the lock file already exists. All we have
+ ** to do is adjust our internal record of the lock level.
+ */
+ if( pFile->eFileLock > NO_LOCK ){
+ pFile->eFileLock = eFileLock;
+ /* Always update the timestamp on the old file */
+#ifdef HAVE_UTIME
+ utime(zLockFile, NULL);
+#else
+ utimes(zLockFile, NULL);
+#endif
+ return SQLITE_OK;
+ }
+
+ /* grab an exclusive lock */
+ rc = osMkdir(zLockFile, 0777);
+ if( rc<0 ){
+ /* failed to open/create the lock directory */
+ int tErrno = errno;
+ if( EEXIST == tErrno ){
+ rc = SQLITE_BUSY;
+ } else {
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ if( rc!=SQLITE_BUSY ){
+ storeLastErrno(pFile, tErrno);
+ }
+ }
+ return rc;
+ }
+
+ /* got it, set the type and return ok */
+ pFile->eFileLock = eFileLock;
+ return rc;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+**
+** When the locking level reaches NO_LOCK, delete the lock file.
+*/
+static int dotlockUnlock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ char *zLockFile = (char *)pFile->lockingContext;
+ int rc;
+
+ assert( pFile );
+ OSTRACE(("UNLOCK %d %d was %d pid=%d (dotlock)\n", pFile->h, eFileLock,
+ pFile->eFileLock, osGetpid(0)));
+ assert( eFileLock<=SHARED_LOCK );
+
+ /* no-op if possible */
+ if( pFile->eFileLock==eFileLock ){
+ return SQLITE_OK;
+ }
+
+ /* To downgrade to shared, simply update our internal notion of the
+ ** lock state. No need to mess with the file on disk.
+ */
+ if( eFileLock==SHARED_LOCK ){
+ pFile->eFileLock = SHARED_LOCK;
+ return SQLITE_OK;
+ }
+
+ /* To fully unlock the database, delete the lock file */
+ assert( eFileLock==NO_LOCK );
+ rc = osRmdir(zLockFile);
+ if( rc<0 ){
+ int tErrno = errno;
+ if( tErrno==ENOENT ){
+ rc = SQLITE_OK;
+ }else{
+ rc = SQLITE_IOERR_UNLOCK;
+ storeLastErrno(pFile, tErrno);
+ }
+ return rc;
+ }
+ pFile->eFileLock = NO_LOCK;
+ return SQLITE_OK;
+}
+
+/*
+** Close a file. Make sure the lock has been released before closing.
+*/
+static int dotlockClose(sqlite3_file *id) {
+ unixFile *pFile = (unixFile*)id;
+ assert( id!=0 );
+ dotlockUnlock(id, NO_LOCK);
+ sqlite3_free(pFile->lockingContext);
+ return closeUnixFile(id);
+}
+/****************** End of the dot-file lock implementation *******************
+******************************************************************************/
+
+/******************************************************************************
+************************** Begin flock Locking ********************************
+**
+** Use the flock() system call to do file locking.
+**
+** flock() locking is like dot-file locking in that the various
+** fine-grain locking levels supported by SQLite are collapsed into
+** a single exclusive lock. In other words, SHARED, RESERVED, and
+** PENDING locks are the same thing as an EXCLUSIVE lock. SQLite
+** still works when you do this, but concurrency is reduced since
+** only a single process can be reading the database at a time.
+**
+** Omit this section if SQLITE_ENABLE_LOCKING_STYLE is turned off
+*/
+#if SQLITE_ENABLE_LOCKING_STYLE
+
+/*
+** Retry flock() calls that fail with EINTR
+*/
+#ifdef EINTR
+static int robust_flock(int fd, int op){
+ int rc;
+ do{ rc = flock(fd,op); }while( rc<0 && errno==EINTR );
+ return rc;
+}
+#else
+# define robust_flock(a,b) flock(a,b)
+#endif
+
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int flockCheckReservedLock(sqlite3_file *id, int *pResOut){
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->eFileLock>SHARED_LOCK ){
+ reserved = 1;
+ }
+
+ /* Otherwise see if some other process holds it. */
+ if( !reserved ){
+ /* attempt to get the lock */
+ int lrc = robust_flock(pFile->h, LOCK_EX | LOCK_NB);
+ if( !lrc ){
+ /* got the lock, unlock it */
+ lrc = robust_flock(pFile->h, LOCK_UN);
+ if ( lrc ) {
+ int tErrno = errno;
+ /* unlock failed with an error */
+ lrc = SQLITE_IOERR_UNLOCK;
+ storeLastErrno(pFile, tErrno);
+ rc = lrc;
+ }
+ } else {
+ int tErrno = errno;
+ reserved = 1;
+ /* someone else might have it reserved */
+ lrc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ if( IS_LOCK_ERROR(lrc) ){
+ storeLastErrno(pFile, tErrno);
+ rc = lrc;
+ }
+ }
+ }
+ OSTRACE(("TEST WR-LOCK %d %d %d (flock)\n", pFile->h, rc, reserved));
+
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+ if( (rc & 0xff) == SQLITE_IOERR ){
+ rc = SQLITE_OK;
+ reserved=1;
+ }
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** flock() only really support EXCLUSIVE locks. We track intermediate
+** lock states in the sqlite3_file structure, but all locks SHARED or
+** above are really EXCLUSIVE locks and exclude all other processes from
+** access the file.
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int flockLock(sqlite3_file *id, int eFileLock) {
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+
+ assert( pFile );
+
+ /* if we already have a lock, it is exclusive.
+ ** Just adjust level and punt on outta here. */
+ if (pFile->eFileLock > NO_LOCK) {
+ pFile->eFileLock = eFileLock;
+ return SQLITE_OK;
+ }
+
+ /* grab an exclusive lock */
+
+ if (robust_flock(pFile->h, LOCK_EX | LOCK_NB)) {
+ int tErrno = errno;
+ /* didn't get, must be busy */
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ if( IS_LOCK_ERROR(rc) ){
+ storeLastErrno(pFile, tErrno);
+ }
+ } else {
+ /* got it, set the type and return ok */
+ pFile->eFileLock = eFileLock;
+ }
+ OSTRACE(("LOCK %d %s %s (flock)\n", pFile->h, azFileLock(eFileLock),
+ rc==SQLITE_OK ? "ok" : "failed"));
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+ if( (rc & 0xff) == SQLITE_IOERR ){
+ rc = SQLITE_BUSY;
+ }
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+ return rc;
+}
+
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int flockUnlock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+
+ assert( pFile );
+ OSTRACE(("UNLOCK %d %d was %d pid=%d (flock)\n", pFile->h, eFileLock,
+ pFile->eFileLock, osGetpid(0)));
+ assert( eFileLock<=SHARED_LOCK );
+
+ /* no-op if possible */
+ if( pFile->eFileLock==eFileLock ){
+ return SQLITE_OK;
+ }
+
+ /* shared can just be set because we always have an exclusive */
+ if (eFileLock==SHARED_LOCK) {
+ pFile->eFileLock = eFileLock;
+ return SQLITE_OK;
+ }
+
+ /* no, really, unlock. */
+ if( robust_flock(pFile->h, LOCK_UN) ){
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+ return SQLITE_OK;
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+ return SQLITE_IOERR_UNLOCK;
+ }else{
+ pFile->eFileLock = NO_LOCK;
+ return SQLITE_OK;
+ }
+}
+
+/*
+** Close a file.
+*/
+static int flockClose(sqlite3_file *id) {
+ assert( id!=0 );
+ flockUnlock(id, NO_LOCK);
+ return closeUnixFile(id);
+}
+
+#endif /* SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORK */
+
+/******************* End of the flock lock implementation *********************
+******************************************************************************/
+
+/******************************************************************************
+************************ Begin Named Semaphore Locking ************************
+**
+** Named semaphore locking is only supported on VxWorks.
+**
+** Semaphore locking is like dot-lock and flock in that it really only
+** supports EXCLUSIVE locking. Only a single process can read or write
+** the database file at a time. This reduces potential concurrency, but
+** makes the lock implementation much easier.
+*/
+#if OS_VXWORKS
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int semXCheckReservedLock(sqlite3_file *id, int *pResOut) {
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->eFileLock>SHARED_LOCK ){
+ reserved = 1;
+ }
+
+ /* Otherwise see if some other process holds it. */
+ if( !reserved ){
+ sem_t *pSem = pFile->pInode->pSem;
+
+ if( sem_trywait(pSem)==-1 ){
+ int tErrno = errno;
+ if( EAGAIN != tErrno ){
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_CHECKRESERVEDLOCK);
+ storeLastErrno(pFile, tErrno);
+ } else {
+ /* someone else has the lock when we are in NO_LOCK */
+ reserved = (pFile->eFileLock < SHARED_LOCK);
+ }
+ }else{
+ /* we could have it if we want it */
+ sem_post(pSem);
+ }
+ }
+ OSTRACE(("TEST WR-LOCK %d %d %d (sem)\n", pFile->h, rc, reserved));
+
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** Semaphore locks only really support EXCLUSIVE locks. We track intermediate
+** lock states in the sqlite3_file structure, but all locks SHARED or
+** above are really EXCLUSIVE locks and exclude all other processes from
+** access the file.
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int semXLock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ sem_t *pSem = pFile->pInode->pSem;
+ int rc = SQLITE_OK;
+
+ /* if we already have a lock, it is exclusive.
+ ** Just adjust level and punt on outta here. */
+ if (pFile->eFileLock > NO_LOCK) {
+ pFile->eFileLock = eFileLock;
+ rc = SQLITE_OK;
+ goto sem_end_lock;
+ }
+
+ /* lock semaphore now but bail out when already locked. */
+ if( sem_trywait(pSem)==-1 ){
+ rc = SQLITE_BUSY;
+ goto sem_end_lock;
+ }
+
+ /* got it, set the type and return ok */
+ pFile->eFileLock = eFileLock;
+
+ sem_end_lock:
+ return rc;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int semXUnlock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ sem_t *pSem = pFile->pInode->pSem;
+
+ assert( pFile );
+ assert( pSem );
+ OSTRACE(("UNLOCK %d %d was %d pid=%d (sem)\n", pFile->h, eFileLock,
+ pFile->eFileLock, osGetpid(0)));
+ assert( eFileLock<=SHARED_LOCK );
+
+ /* no-op if possible */
+ if( pFile->eFileLock==eFileLock ){
+ return SQLITE_OK;
+ }
+
+ /* shared can just be set because we always have an exclusive */
+ if (eFileLock==SHARED_LOCK) {
+ pFile->eFileLock = eFileLock;
+ return SQLITE_OK;
+ }
+
+ /* no, really unlock. */
+ if ( sem_post(pSem)==-1 ) {
+ int rc, tErrno = errno;
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
+ if( IS_LOCK_ERROR(rc) ){
+ storeLastErrno(pFile, tErrno);
+ }
+ return rc;
+ }
+ pFile->eFileLock = NO_LOCK;
+ return SQLITE_OK;
+}
+
+/*
+ ** Close a file.
+ */
+static int semXClose(sqlite3_file *id) {
+ if( id ){
+ unixFile *pFile = (unixFile*)id;
+ semXUnlock(id, NO_LOCK);
+ assert( pFile );
+ assert( unixFileMutexNotheld(pFile) );
+ unixEnterMutex();
+ releaseInodeInfo(pFile);
+ unixLeaveMutex();
+ closeUnixFile(id);
+ }
+ return SQLITE_OK;
+}
+
+#endif /* OS_VXWORKS */
+/*
+** Named semaphore locking is only available on VxWorks.
+**
+*************** End of the named semaphore lock implementation ****************
+******************************************************************************/
+
+
+/******************************************************************************
+*************************** Begin AFP Locking *********************************
+**
+** AFP is the Apple Filing Protocol. AFP is a network filesystem found
+** on Apple Macintosh computers - both OS9 and OSX.
+**
+** Third-party implementations of AFP are available. But this code here
+** only works on OSX.
+*/
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+/*
+** The afpLockingContext structure contains all afp lock specific state
+*/
+typedef struct afpLockingContext afpLockingContext;
+struct afpLockingContext {
+ int reserved;
+ const char *dbPath; /* Name of the open file */
+};
+
+struct ByteRangeLockPB2
+{
+ unsigned long long offset; /* offset to first byte to lock */
+ unsigned long long length; /* nbr of bytes to lock */
+ unsigned long long retRangeStart; /* nbr of 1st byte locked if successful */
+ unsigned char unLockFlag; /* 1 = unlock, 0 = lock */
+ unsigned char startEndFlag; /* 1=rel to end of fork, 0=rel to start */
+ int fd; /* file desc to assoc this lock with */
+};
+
+#define afpfsByteRangeLock2FSCTL _IOWR('z', 23, struct ByteRangeLockPB2)
+
+/*
+** This is a utility for setting or clearing a bit-range lock on an
+** AFP filesystem.
+**
+** Return SQLITE_OK on success, SQLITE_BUSY on failure.
+*/
+static int afpSetLock(
+ const char *path, /* Name of the file to be locked or unlocked */
+ unixFile *pFile, /* Open file descriptor on path */
+ unsigned long long offset, /* First byte to be locked */
+ unsigned long long length, /* Number of bytes to lock */
+ int setLockFlag /* True to set lock. False to clear lock */
+){
+ struct ByteRangeLockPB2 pb;
+ int err;
+
+ pb.unLockFlag = setLockFlag ? 0 : 1;
+ pb.startEndFlag = 0;
+ pb.offset = offset;
+ pb.length = length;
+ pb.fd = pFile->h;
+
+ OSTRACE(("AFPSETLOCK [%s] for %d%s in range %llx:%llx\n",
+ (setLockFlag?"ON":"OFF"), pFile->h, (pb.fd==-1?"[testval-1]":""),
+ offset, length));
+ err = fsctl(path, afpfsByteRangeLock2FSCTL, &pb, 0);
+ if ( err==-1 ) {
+ int rc;
+ int tErrno = errno;
+ OSTRACE(("AFPSETLOCK failed to fsctl() '%s' %d %s\n",
+ path, tErrno, strerror(tErrno)));
+#ifdef SQLITE_IGNORE_AFP_LOCK_ERRORS
+ rc = SQLITE_BUSY;
+#else
+ rc = sqliteErrorFromPosixError(tErrno,
+ setLockFlag ? SQLITE_IOERR_LOCK : SQLITE_IOERR_UNLOCK);
+#endif /* SQLITE_IGNORE_AFP_LOCK_ERRORS */
+ if( IS_LOCK_ERROR(rc) ){
+ storeLastErrno(pFile, tErrno);
+ }
+ return rc;
+ } else {
+ return SQLITE_OK;
+ }
+}
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int afpCheckReservedLock(sqlite3_file *id, int *pResOut){
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+ afpLockingContext *context;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+ context = (afpLockingContext *) pFile->lockingContext;
+ if( context->reserved ){
+ *pResOut = 1;
+ return SQLITE_OK;
+ }
+ sqlite3_mutex_enter(pFile->pInode->pLockMutex);
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->pInode->eFileLock>SHARED_LOCK ){
+ reserved = 1;
+ }
+
+ /* Otherwise see if some other process holds it.
+ */
+ if( !reserved ){
+ /* lock the RESERVED byte */
+ int lrc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);
+ if( SQLITE_OK==lrc ){
+ /* if we succeeded in taking the reserved lock, unlock it to restore
+ ** the original state */
+ lrc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1, 0);
+ } else {
+ /* if we failed to get the lock then someone else must have it */
+ reserved = 1;
+ }
+ if( IS_LOCK_ERROR(lrc) ){
+ rc=lrc;
+ }
+ }
+
+ sqlite3_mutex_leave(pFile->pInode->pLockMutex);
+ OSTRACE(("TEST WR-LOCK %d %d %d (afp)\n", pFile->h, rc, reserved));
+
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int afpLock(sqlite3_file *id, int eFileLock){
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+ unixInodeInfo *pInode = pFile->pInode;
+ afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
+
+ assert( pFile );
+ OSTRACE(("LOCK %d %s was %s(%s,%d) pid=%d (afp)\n", pFile->h,
+ azFileLock(eFileLock), azFileLock(pFile->eFileLock),
+ azFileLock(pInode->eFileLock), pInode->nShared , osGetpid(0)));
+
+ /* If there is already a lock of this type or more restrictive on the
+ ** unixFile, do nothing. Don't use the afp_end_lock: exit path, as
+ ** unixEnterMutex() hasn't been called yet.
+ */
+ if( pFile->eFileLock>=eFileLock ){
+ OSTRACE(("LOCK %d %s ok (already held) (afp)\n", pFile->h,
+ azFileLock(eFileLock)));
+ return SQLITE_OK;
+ }
+
+ /* Make sure the locking sequence is correct
+ ** (1) We never move from unlocked to anything higher than shared lock.
+ ** (2) SQLite never explicitly requests a pendig lock.
+ ** (3) A shared lock is always held when a reserve lock is requested.
+ */
+ assert( pFile->eFileLock!=NO_LOCK || eFileLock==SHARED_LOCK );
+ assert( eFileLock!=PENDING_LOCK );
+ assert( eFileLock!=RESERVED_LOCK || pFile->eFileLock==SHARED_LOCK );
+
+ /* This mutex is needed because pFile->pInode is shared across threads
+ */
+ pInode = pFile->pInode;
+ sqlite3_mutex_enter(pInode->pLockMutex);
+
+ /* If some thread using this PID has a lock via a different unixFile*
+ ** handle that precludes the requested lock, return BUSY.
+ */
+ if( (pFile->eFileLock!=pInode->eFileLock &&
+ (pInode->eFileLock>=PENDING_LOCK || eFileLock>SHARED_LOCK))
+ ){
+ rc = SQLITE_BUSY;
+ goto afp_end_lock;
+ }
+
+ /* If a SHARED lock is requested, and some thread using this PID already
+ ** has a SHARED or RESERVED lock, then increment reference counts and
+ ** return SQLITE_OK.
+ */
+ if( eFileLock==SHARED_LOCK &&
+ (pInode->eFileLock==SHARED_LOCK || pInode->eFileLock==RESERVED_LOCK) ){
+ assert( eFileLock==SHARED_LOCK );
+ assert( pFile->eFileLock==0 );
+ assert( pInode->nShared>0 );
+ pFile->eFileLock = SHARED_LOCK;
+ pInode->nShared++;
+ pInode->nLock++;
+ goto afp_end_lock;
+ }
+
+ /* A PENDING lock is needed before acquiring a SHARED lock and before
+ ** acquiring an EXCLUSIVE lock. For the SHARED lock, the PENDING will
+ ** be released.
+ */
+ if( eFileLock==SHARED_LOCK
+ || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLockdbPath, pFile, PENDING_BYTE, 1, 1);
+ if (failed) {
+ rc = failed;
+ goto afp_end_lock;
+ }
+ }
+
+ /* If control gets to this point, then actually go ahead and make
+ ** operating system calls for the specified lock.
+ */
+ if( eFileLock==SHARED_LOCK ){
+ int lrc1, lrc2, lrc1Errno = 0;
+ long lk, mask;
+
+ assert( pInode->nShared==0 );
+ assert( pInode->eFileLock==0 );
+
+ mask = (sizeof(long)==8) ? LARGEST_INT64 : 0x7fffffff;
+ /* Now get the read-lock SHARED_LOCK */
+ /* note that the quality of the randomness doesn't matter that much */
+ lk = random();
+ pInode->sharedByte = (lk & mask)%(SHARED_SIZE - 1);
+ lrc1 = afpSetLock(context->dbPath, pFile,
+ SHARED_FIRST+pInode->sharedByte, 1, 1);
+ if( IS_LOCK_ERROR(lrc1) ){
+ lrc1Errno = pFile->lastErrno;
+ }
+ /* Drop the temporary PENDING lock */
+ lrc2 = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 0);
+
+ if( IS_LOCK_ERROR(lrc1) ) {
+ storeLastErrno(pFile, lrc1Errno);
+ rc = lrc1;
+ goto afp_end_lock;
+ } else if( IS_LOCK_ERROR(lrc2) ){
+ rc = lrc2;
+ goto afp_end_lock;
+ } else if( lrc1 != SQLITE_OK ) {
+ rc = lrc1;
+ } else {
+ pFile->eFileLock = SHARED_LOCK;
+ pInode->nLock++;
+ pInode->nShared = 1;
+ }
+ }else if( eFileLock==EXCLUSIVE_LOCK && pInode->nShared>1 ){
+ /* We are trying for an exclusive lock but another thread in this
+ ** same process is still holding a shared lock. */
+ rc = SQLITE_BUSY;
+ }else{
+ /* The request was for a RESERVED or EXCLUSIVE lock. It is
+ ** assumed that there is a SHARED or greater lock on the file
+ ** already.
+ */
+ int failed = 0;
+ assert( 0!=pFile->eFileLock );
+ if (eFileLock >= RESERVED_LOCK && pFile->eFileLock < RESERVED_LOCK) {
+ /* Acquire a RESERVED lock */
+ failed = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);
+ if( !failed ){
+ context->reserved = 1;
+ }
+ }
+ if (!failed && eFileLock == EXCLUSIVE_LOCK) {
+ /* Acquire an EXCLUSIVE lock */
+
+ /* Remove the shared lock before trying the range. we'll need to
+ ** reestablish the shared lock if we can't get the afpUnlock
+ */
+ if( !(failed = afpSetLock(context->dbPath, pFile, SHARED_FIRST +
+ pInode->sharedByte, 1, 0)) ){
+ int failed2 = SQLITE_OK;
+ /* now attemmpt to get the exclusive lock range */
+ failed = afpSetLock(context->dbPath, pFile, SHARED_FIRST,
+ SHARED_SIZE, 1);
+ if( failed && (failed2 = afpSetLock(context->dbPath, pFile,
+ SHARED_FIRST + pInode->sharedByte, 1, 1)) ){
+ /* Can't reestablish the shared lock. Sqlite can't deal, this is
+ ** a critical I/O error
+ */
+ rc = ((failed & 0xff) == SQLITE_IOERR) ? failed2 :
+ SQLITE_IOERR_LOCK;
+ goto afp_end_lock;
+ }
+ }else{
+ rc = failed;
+ }
+ }
+ if( failed ){
+ rc = failed;
+ }
+ }
+
+ if( rc==SQLITE_OK ){
+ pFile->eFileLock = eFileLock;
+ pInode->eFileLock = eFileLock;
+ }else if( eFileLock==EXCLUSIVE_LOCK ){
+ pFile->eFileLock = PENDING_LOCK;
+ pInode->eFileLock = PENDING_LOCK;
+ }
+
+afp_end_lock:
+ sqlite3_mutex_leave(pInode->pLockMutex);
+ OSTRACE(("LOCK %d %s %s (afp)\n", pFile->h, azFileLock(eFileLock),
+ rc==SQLITE_OK ? "ok" : "failed"));
+ return rc;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int afpUnlock(sqlite3_file *id, int eFileLock) {
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+ unixInodeInfo *pInode;
+ afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
+ int skipShared = 0;
+#ifdef SQLITE_TEST
+ int h = pFile->h;
+#endif
+
+ assert( pFile );
+ OSTRACE(("UNLOCK %d %d was %d(%d,%d) pid=%d (afp)\n", pFile->h, eFileLock,
+ pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
+ osGetpid(0)));
+
+ assert( eFileLock<=SHARED_LOCK );
+ if( pFile->eFileLock<=eFileLock ){
+ return SQLITE_OK;
+ }
+ pInode = pFile->pInode;
+ sqlite3_mutex_enter(pInode->pLockMutex);
+ assert( pInode->nShared!=0 );
+ if( pFile->eFileLock>SHARED_LOCK ){
+ assert( pInode->eFileLock==pFile->eFileLock );
+ SimulateIOErrorBenign(1);
+ SimulateIOError( h=(-1) )
+ SimulateIOErrorBenign(0);
+
+#ifdef SQLITE_DEBUG
+ /* When reducing a lock such that other processes can start
+ ** reading the database file again, make sure that the
+ ** transaction counter was updated if any part of the database
+ ** file changed. If the transaction counter is not updated,
+ ** other connections to the same file might not realize that
+ ** the file has changed and hence might not know to flush their
+ ** cache. The use of a stale cache can lead to database corruption.
+ */
+ assert( pFile->inNormalWrite==0
+ || pFile->dbUpdate==0
+ || pFile->transCntrChng==1 );
+ pFile->inNormalWrite = 0;
+#endif
+
+ if( pFile->eFileLock==EXCLUSIVE_LOCK ){
+ rc = afpSetLock(context->dbPath, pFile, SHARED_FIRST, SHARED_SIZE, 0);
+ if( rc==SQLITE_OK && (eFileLock==SHARED_LOCK || pInode->nShared>1) ){
+ /* only re-establish the shared lock if necessary */
+ int sharedLockByte = SHARED_FIRST+pInode->sharedByte;
+ rc = afpSetLock(context->dbPath, pFile, sharedLockByte, 1, 1);
+ } else {
+ skipShared = 1;
+ }
+ }
+ if( rc==SQLITE_OK && pFile->eFileLock>=PENDING_LOCK ){
+ rc = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 0);
+ }
+ if( rc==SQLITE_OK && pFile->eFileLock>=RESERVED_LOCK && context->reserved ){
+ rc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1, 0);
+ if( !rc ){
+ context->reserved = 0;
+ }
+ }
+ if( rc==SQLITE_OK && (eFileLock==SHARED_LOCK || pInode->nShared>1)){
+ pInode->eFileLock = SHARED_LOCK;
+ }
+ }
+ if( rc==SQLITE_OK && eFileLock==NO_LOCK ){
+
+ /* Decrement the shared lock counter. Release the lock using an
+ ** OS call only when all threads in this same process have released
+ ** the lock.
+ */
+ unsigned long long sharedLockByte = SHARED_FIRST+pInode->sharedByte;
+ pInode->nShared--;
+ if( pInode->nShared==0 ){
+ SimulateIOErrorBenign(1);
+ SimulateIOError( h=(-1) )
+ SimulateIOErrorBenign(0);
+ if( !skipShared ){
+ rc = afpSetLock(context->dbPath, pFile, sharedLockByte, 1, 0);
+ }
+ if( !rc ){
+ pInode->eFileLock = NO_LOCK;
+ pFile->eFileLock = NO_LOCK;
+ }
+ }
+ if( rc==SQLITE_OK ){
+ pInode->nLock--;
+ assert( pInode->nLock>=0 );
+ if( pInode->nLock==0 ) closePendingFds(pFile);
+ }
+ }
+
+ sqlite3_mutex_leave(pInode->pLockMutex);
+ if( rc==SQLITE_OK ){
+ pFile->eFileLock = eFileLock;
+ }
+ return rc;
+}
+
+/*
+** Close a file & cleanup AFP specific locking context
+*/
+static int afpClose(sqlite3_file *id) {
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+ assert( id!=0 );
+ afpUnlock(id, NO_LOCK);
+ assert( unixFileMutexNotheld(pFile) );
+ unixEnterMutex();
+ if( pFile->pInode ){
+ unixInodeInfo *pInode = pFile->pInode;
+ sqlite3_mutex_enter(pInode->pLockMutex);
+ if( pInode->nLock ){
+ /* If there are outstanding locks, do not actually close the file just
+ ** yet because that would clear those locks. Instead, add the file
+ ** descriptor to pInode->aPending. It will be automatically closed when
+ ** the last lock is cleared.
+ */
+ setPendingFd(pFile);
+ }
+ sqlite3_mutex_leave(pInode->pLockMutex);
+ }
+ releaseInodeInfo(pFile);
+ sqlite3_free(pFile->lockingContext);
+ rc = closeUnixFile(id);
+ unixLeaveMutex();
+ return rc;
+}
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+/*
+** The code above is the AFP lock implementation. The code is specific
+** to MacOSX and does not work on other unix platforms. No alternative
+** is available. If you don't compile for a mac, then the "unix-afp"
+** VFS is not available.
+**
+********************* End of the AFP lock implementation **********************
+******************************************************************************/
+
+/******************************************************************************
+*************************** Begin NFS Locking ********************************/
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+/*
+ ** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+ ** must be either NO_LOCK or SHARED_LOCK.
+ **
+ ** If the locking level of the file descriptor is already at or below
+ ** the requested locking level, this routine is a no-op.
+ */
+static int nfsUnlock(sqlite3_file *id, int eFileLock){
+ return posixUnlock(id, eFileLock, 1);
+}
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+/*
+** The code above is the NFS lock implementation. The code is specific
+** to MacOSX and does not work on other unix platforms. No alternative
+** is available.
+**
+********************* End of the NFS lock implementation **********************
+******************************************************************************/
+
+/******************************************************************************
+**************** Non-locking sqlite3_file methods *****************************
+**
+** The next division contains implementations for all methods of the
+** sqlite3_file object other than the locking methods. The locking
+** methods were defined in divisions above (one locking method per
+** division). Those methods that are common to all locking modes
+** are gather together into this division.
+*/
+
+/*
+** Seek to the offset passed as the second argument, then read cnt
+** bytes into pBuf. Return the number of bytes actually read.
+**
+** NB: If you define USE_PREAD or USE_PREAD64, then it might also
+** be necessary to define _XOPEN_SOURCE to be 500. This varies from
+** one system to another. Since SQLite does not define USE_PREAD
+** in any form by default, we will not attempt to define _XOPEN_SOURCE.
+** See tickets #2741 and #2681.
+**
+** To avoid stomping the errno value on a failed read the lastErrno value
+** is set before returning.
+*/
+static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){
+ int got;
+ int prior = 0;
+#if (!defined(USE_PREAD) && !defined(USE_PREAD64))
+ i64 newOffset;
+#endif
+ TIMER_START;
+ assert( cnt==(cnt&0x1ffff) );
+ assert( id->h>2 );
+ do{
+#if defined(USE_PREAD)
+ got = osPread(id->h, pBuf, cnt, offset);
+ SimulateIOError( got = -1 );
+#elif defined(USE_PREAD64)
+ got = osPread64(id->h, pBuf, cnt, offset);
+ SimulateIOError( got = -1 );
+#else
+ newOffset = lseek(id->h, offset, SEEK_SET);
+ SimulateIOError( newOffset = -1 );
+ if( newOffset<0 ){
+ storeLastErrno((unixFile*)id, errno);
+ return -1;
+ }
+ got = osRead(id->h, pBuf, cnt);
+#endif
+ if( got==cnt ) break;
+ if( got<0 ){
+ if( errno==EINTR ){ got = 1; continue; }
+ prior = 0;
+ storeLastErrno((unixFile*)id, errno);
+ break;
+ }else if( got>0 ){
+ cnt -= got;
+ offset += got;
+ prior += got;
+ pBuf = (void*)(got + (char*)pBuf);
+ }
+ }while( got>0 );
+ TIMER_END;
+ OSTRACE(("READ %-3d %5d %7lld %llu\n",
+ id->h, got+prior, offset-prior, TIMER_ELAPSED));
+ return got+prior;
+}
+
+/*
+** Read data from a file into a buffer. Return SQLITE_OK if all
+** bytes were read successfully and SQLITE_IOERR if anything goes
+** wrong.
+*/
+static int unixRead(
+ sqlite3_file *id,
+ void *pBuf,
+ int amt,
+ sqlite3_int64 offset
+){
+ unixFile *pFile = (unixFile *)id;
+ int got;
+ assert( id );
+ assert( offset>=0 );
+ assert( amt>0 );
+
+ /* If this is a database file (not a journal, master-journal or temp
+ ** file), the bytes in the locking range should never be read or written. */
+#if 0
+ assert( pFile->pPreallocatedUnused==0
+ || offset>=PENDING_BYTE+512
+ || offset+amt<=PENDING_BYTE
+ );
+#endif
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* Deal with as much of this read request as possible by transfering
+ ** data from the memory mapping using memcpy(). */
+ if( offsetmmapSize ){
+ if( offset+amt <= pFile->mmapSize ){
+ memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
+ return SQLITE_OK;
+ }else{
+ int nCopy = pFile->mmapSize - offset;
+ memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
+ pBuf = &((u8 *)pBuf)[nCopy];
+ amt -= nCopy;
+ offset += nCopy;
+ }
+ }
+#endif
+
+ got = seekAndRead(pFile, offset, pBuf, amt);
+ if( got==amt ){
+ return SQLITE_OK;
+ }else if( got<0 ){
+ /* lastErrno set by seekAndRead */
+ return SQLITE_IOERR_READ;
+ }else{
+ storeLastErrno(pFile, 0); /* not a system error */
+ /* Unread parts of the buffer must be zero-filled */
+ memset(&((char*)pBuf)[got], 0, amt-got);
+ return SQLITE_IOERR_SHORT_READ;
+ }
+}
+
+/*
+** Attempt to seek the file-descriptor passed as the first argument to
+** absolute offset iOff, then attempt to write nBuf bytes of data from
+** pBuf to it. If an error occurs, return -1 and set *piErrno. Otherwise,
+** return the actual number of bytes written (which may be less than
+** nBuf).
+*/
+static int seekAndWriteFd(
+ int fd, /* File descriptor to write to */
+ i64 iOff, /* File offset to begin writing at */
+ const void *pBuf, /* Copy data from this buffer to the file */
+ int nBuf, /* Size of buffer pBuf in bytes */
+ int *piErrno /* OUT: Error number if error occurs */
+){
+ int rc = 0; /* Value returned by system call */
+
+ assert( nBuf==(nBuf&0x1ffff) );
+ assert( fd>2 );
+ assert( piErrno!=0 );
+ nBuf &= 0x1ffff;
+ TIMER_START;
+
+#if defined(USE_PREAD)
+ do{ rc = (int)osPwrite(fd, pBuf, nBuf, iOff); }while( rc<0 && errno==EINTR );
+#elif defined(USE_PREAD64)
+ do{ rc = (int)osPwrite64(fd, pBuf, nBuf, iOff);}while( rc<0 && errno==EINTR);
+#else
+ do{
+ i64 iSeek = lseek(fd, iOff, SEEK_SET);
+ SimulateIOError( iSeek = -1 );
+ if( iSeek<0 ){
+ rc = -1;
+ break;
+ }
+ rc = osWrite(fd, pBuf, nBuf);
+ }while( rc<0 && errno==EINTR );
+#endif
+
+ TIMER_END;
+ OSTRACE(("WRITE %-3d %5d %7lld %llu\n", fd, rc, iOff, TIMER_ELAPSED));
+
+ if( rc<0 ) *piErrno = errno;
+ return rc;
+}
+
+
+/*
+** Seek to the offset in id->offset then read cnt bytes into pBuf.
+** Return the number of bytes actually read. Update the offset.
+**
+** To avoid stomping the errno value on a failed write the lastErrno value
+** is set before returning.
+*/
+static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){
+ return seekAndWriteFd(id->h, offset, pBuf, cnt, &id->lastErrno);
+}
+
+
+/*
+** Write data from a buffer into a file. Return SQLITE_OK on success
+** or some other error code on failure.
+*/
+static int unixWrite(
+ sqlite3_file *id,
+ const void *pBuf,
+ int amt,
+ sqlite3_int64 offset
+){
+ unixFile *pFile = (unixFile*)id;
+ int wrote = 0;
+ assert( id );
+ assert( amt>0 );
+
+ /* If this is a database file (not a journal, master-journal or temp
+ ** file), the bytes in the locking range should never be read or written. */
+#if 0
+ assert( pFile->pPreallocatedUnused==0
+ || offset>=PENDING_BYTE+512
+ || offset+amt<=PENDING_BYTE
+ );
+#endif
+
+#ifdef SQLITE_DEBUG
+ /* If we are doing a normal write to a database file (as opposed to
+ ** doing a hot-journal rollback or a write to some file other than a
+ ** normal database file) then record the fact that the database
+ ** has changed. If the transaction counter is modified, record that
+ ** fact too.
+ */
+ if( pFile->inNormalWrite ){
+ pFile->dbUpdate = 1; /* The database has been modified */
+ if( offset<=24 && offset+amt>=27 ){
+ int rc;
+ char oldCntr[4];
+ SimulateIOErrorBenign(1);
+ rc = seekAndRead(pFile, 24, oldCntr, 4);
+ SimulateIOErrorBenign(0);
+ if( rc!=4 || memcmp(oldCntr, &((char*)pBuf)[24-offset], 4)!=0 ){
+ pFile->transCntrChng = 1; /* The transaction counter has changed */
+ }
+ }
+ }
+#endif
+
+#if defined(SQLITE_MMAP_READWRITE) && SQLITE_MAX_MMAP_SIZE>0
+ /* Deal with as much of this write request as possible by transfering
+ ** data from the memory mapping using memcpy(). */
+ if( offsetmmapSize ){
+ if( offset+amt <= pFile->mmapSize ){
+ memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
+ return SQLITE_OK;
+ }else{
+ int nCopy = pFile->mmapSize - offset;
+ memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
+ pBuf = &((u8 *)pBuf)[nCopy];
+ amt -= nCopy;
+ offset += nCopy;
+ }
+ }
+#endif
+
+ while( (wrote = seekAndWrite(pFile, offset, pBuf, amt))0 ){
+ amt -= wrote;
+ offset += wrote;
+ pBuf = &((char*)pBuf)[wrote];
+ }
+ SimulateIOError(( wrote=(-1), amt=1 ));
+ SimulateDiskfullError(( wrote=0, amt=1 ));
+
+ if( amt>wrote ){
+ if( wrote<0 && pFile->lastErrno!=ENOSPC ){
+ /* lastErrno set by seekAndWrite */
+ return SQLITE_IOERR_WRITE;
+ }else{
+ storeLastErrno(pFile, 0); /* not a system error */
+ return SQLITE_FULL;
+ }
+ }
+
+ return SQLITE_OK;
+}
+
+#ifdef SQLITE_TEST
+/*
+** Count the number of fullsyncs and normal syncs. This is used to test
+** that syncs and fullsyncs are occurring at the right times.
+*/
+SQLITE_API int sqlite3_sync_count = 0;
+SQLITE_API int sqlite3_fullsync_count = 0;
+#endif
+
+/*
+** We do not trust systems to provide a working fdatasync(). Some do.
+** Others do no. To be safe, we will stick with the (slightly slower)
+** fsync(). If you know that your system does support fdatasync() correctly,
+** then simply compile with -Dfdatasync=fdatasync or -DHAVE_FDATASYNC
+*/
+#if !defined(fdatasync) && !HAVE_FDATASYNC
+# define fdatasync fsync
+#endif
+
+/*
+** Define HAVE_FULLFSYNC to 0 or 1 depending on whether or not
+** the F_FULLFSYNC macro is defined. F_FULLFSYNC is currently
+** only available on Mac OS X. But that could change.
+*/
+#ifdef F_FULLFSYNC
+# define HAVE_FULLFSYNC 1
+#else
+# define HAVE_FULLFSYNC 0
+#endif
+
+
+/*
+** The fsync() system call does not work as advertised on many
+** unix systems. The following procedure is an attempt to make
+** it work better.
+**
+** The SQLITE_NO_SYNC macro disables all fsync()s. This is useful
+** for testing when we want to run through the test suite quickly.
+** You are strongly advised *not* to deploy with SQLITE_NO_SYNC
+** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash
+** or power failure will likely corrupt the database file.
+**
+** SQLite sets the dataOnly flag if the size of the file is unchanged.
+** The idea behind dataOnly is that it should only write the file content
+** to disk, not the inode. We only set dataOnly if the file size is
+** unchanged since the file size is part of the inode. However,
+** Ted Ts'o tells us that fdatasync() will also write the inode if the
+** file size has changed. The only real difference between fdatasync()
+** and fsync(), Ted tells us, is that fdatasync() will not flush the
+** inode if the mtime or owner or other inode attributes have changed.
+** We only care about the file size, not the other file attributes, so
+** as far as SQLite is concerned, an fdatasync() is always adequate.
+** So, we always use fdatasync() if it is available, regardless of
+** the value of the dataOnly flag.
+*/
+static int full_fsync(int fd, int fullSync, int dataOnly){
+ int rc;
+
+ /* The following "ifdef/elif/else/" block has the same structure as
+ ** the one below. It is replicated here solely to avoid cluttering
+ ** up the real code with the UNUSED_PARAMETER() macros.
+ */
+#ifdef SQLITE_NO_SYNC
+ UNUSED_PARAMETER(fd);
+ UNUSED_PARAMETER(fullSync);
+ UNUSED_PARAMETER(dataOnly);
+#elif HAVE_FULLFSYNC
+ UNUSED_PARAMETER(dataOnly);
+#else
+ UNUSED_PARAMETER(fullSync);
+ UNUSED_PARAMETER(dataOnly);
+#endif
+
+ /* Record the number of times that we do a normal fsync() and
+ ** FULLSYNC. This is used during testing to verify that this procedure
+ ** gets called with the correct arguments.
+ */
+#ifdef SQLITE_TEST
+ if( fullSync ) sqlite3_fullsync_count++;
+ sqlite3_sync_count++;
+#endif
+
+ /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
+ ** no-op. But go ahead and call fstat() to validate the file
+ ** descriptor as we need a method to provoke a failure during
+ ** coverate testing.
+ */
+#ifdef SQLITE_NO_SYNC
+ {
+ struct stat buf;
+ rc = osFstat(fd, &buf);
+ }
+#elif HAVE_FULLFSYNC
+ if( fullSync ){
+ rc = osFcntl(fd, F_FULLFSYNC, 0);
+ }else{
+ rc = 1;
+ }
+ /* If the FULLFSYNC failed, fall back to attempting an fsync().
+ ** It shouldn't be possible for fullfsync to fail on the local
+ ** file system (on OSX), so failure indicates that FULLFSYNC
+ ** isn't supported for this file system. So, attempt an fsync
+ ** and (for now) ignore the overhead of a superfluous fcntl call.
+ ** It'd be better to detect fullfsync support once and avoid
+ ** the fcntl call every time sync is called.
+ */
+ if( rc ) rc = fsync(fd);
+
+#elif defined(__APPLE__)
+ /* fdatasync() on HFS+ doesn't yet flush the file size if it changed correctly
+ ** so currently we default to the macro that redefines fdatasync to fsync
+ */
+ rc = fsync(fd);
+#else
+ rc = fdatasync(fd);
+#if OS_VXWORKS
+ if( rc==-1 && errno==ENOTSUP ){
+ rc = fsync(fd);
+ }
+#endif /* OS_VXWORKS */
+#endif /* ifdef SQLITE_NO_SYNC elif HAVE_FULLFSYNC */
+
+ if( OS_VXWORKS && rc!= -1 ){
+ rc = 0;
+ }
+ return rc;
+}
+
+/*
+** Open a file descriptor to the directory containing file zFilename.
+** If successful, *pFd is set to the opened file descriptor and
+** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM
+** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined
+** value.
+**
+** The directory file descriptor is used for only one thing - to
+** fsync() a directory to make sure file creation and deletion events
+** are flushed to disk. Such fsyncs are not needed on newer
+** journaling filesystems, but are required on older filesystems.
+**
+** This routine can be overridden using the xSetSysCall interface.
+** The ability to override this routine was added in support of the
+** chromium sandbox. Opening a directory is a security risk (we are
+** told) so making it overrideable allows the chromium sandbox to
+** replace this routine with a harmless no-op. To make this routine
+** a no-op, replace it with a stub that returns SQLITE_OK but leaves
+** *pFd set to a negative number.
+**
+** If SQLITE_OK is returned, the caller is responsible for closing
+** the file descriptor *pFd using close().
+*/
+static int openDirectory(const char *zFilename, int *pFd){
+ int ii;
+ int fd = -1;
+ char zDirname[MAX_PATHNAME+1];
+
+ sqlite3_snprintf(MAX_PATHNAME, zDirname, "%s", zFilename);
+ for(ii=(int)strlen(zDirname); ii>0 && zDirname[ii]!='/'; ii--);
+ if( ii>0 ){
+ zDirname[ii] = '\0';
+ }else{
+ if( zDirname[0]!='/' ) zDirname[0] = '.';
+ zDirname[1] = 0;
+ }
+ fd = robust_open(zDirname, O_RDONLY|O_BINARY, 0);
+ if( fd>=0 ){
+ OSTRACE(("OPENDIR %-3d %s\n", fd, zDirname));
+ }
+ *pFd = fd;
+ if( fd>=0 ) return SQLITE_OK;
+ return unixLogError(SQLITE_CANTOPEN_BKPT, "openDirectory", zDirname);
+}
+
+/*
+** Make sure all writes to a particular file are committed to disk.
+**
+** If dataOnly==0 then both the file itself and its metadata (file
+** size, access time, etc) are synced. If dataOnly!=0 then only the
+** file data is synced.
+**
+** Under Unix, also make sure that the directory entry for the file
+** has been created by fsync-ing the directory that contains the file.
+** If we do not do this and we encounter a power failure, the directory
+** entry for the journal might not exist after we reboot. The next
+** SQLite to access the file will not know that the journal exists (because
+** the directory entry for the journal was never created) and the transaction
+** will not roll back - possibly leading to database corruption.
+*/
+static int unixSync(sqlite3_file *id, int flags){
+ int rc;
+ unixFile *pFile = (unixFile*)id;
+
+ int isDataOnly = (flags&SQLITE_SYNC_DATAONLY);
+ int isFullsync = (flags&0x0F)==SQLITE_SYNC_FULL;
+
+ /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
+ assert((flags&0x0F)==SQLITE_SYNC_NORMAL
+ || (flags&0x0F)==SQLITE_SYNC_FULL
+ );
+
+ /* Unix cannot, but some systems may return SQLITE_FULL from here. This
+ ** line is to test that doing so does not cause any problems.
+ */
+ SimulateDiskfullError( return SQLITE_FULL );
+
+ assert( pFile );
+ OSTRACE(("SYNC %-3d\n", pFile->h));
+ rc = full_fsync(pFile->h, isFullsync, isDataOnly);
+ SimulateIOError( rc=1 );
+ if( rc ){
+ storeLastErrno(pFile, errno);
+ return unixLogError(SQLITE_IOERR_FSYNC, "full_fsync", pFile->zPath);
+ }
+
+ /* Also fsync the directory containing the file if the DIRSYNC flag
+ ** is set. This is a one-time occurrence. Many systems (examples: AIX)
+ ** are unable to fsync a directory, so ignore errors on the fsync.
+ */
+ if( pFile->ctrlFlags & UNIXFILE_DIRSYNC ){
+ int dirfd;
+ OSTRACE(("DIRSYNC %s (have_fullfsync=%d fullsync=%d)\n", pFile->zPath,
+ HAVE_FULLFSYNC, isFullsync));
+ rc = osOpenDirectory(pFile->zPath, &dirfd);
+ if( rc==SQLITE_OK ){
+ full_fsync(dirfd, 0, 0);
+ robust_close(pFile, dirfd, __LINE__);
+ }else{
+ assert( rc==SQLITE_CANTOPEN );
+ rc = SQLITE_OK;
+ }
+ pFile->ctrlFlags &= ~UNIXFILE_DIRSYNC;
+ }
+ return rc;
+}
+
+/*
+** Truncate an open file to a specified size
+*/
+static int unixTruncate(sqlite3_file *id, i64 nByte){
+ unixFile *pFile = (unixFile *)id;
+ int rc;
+ assert( pFile );
+ SimulateIOError( return SQLITE_IOERR_TRUNCATE );
+
+ /* If the user has configured a chunk-size for this file, truncate the
+ ** file so that it consists of an integer number of chunks (i.e. the
+ ** actual file size after the operation may be larger than the requested
+ ** size).
+ */
+ if( pFile->szChunk>0 ){
+ nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+ }
+
+ rc = robust_ftruncate(pFile->h, nByte);
+ if( rc ){
+ storeLastErrno(pFile, errno);
+ return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
+ }else{
+#ifdef SQLITE_DEBUG
+ /* If we are doing a normal write to a database file (as opposed to
+ ** doing a hot-journal rollback or a write to some file other than a
+ ** normal database file) and we truncate the file to zero length,
+ ** that effectively updates the change counter. This might happen
+ ** when restoring a database using the backup API from a zero-length
+ ** source.
+ */
+ if( pFile->inNormalWrite && nByte==0 ){
+ pFile->transCntrChng = 1;
+ }
+#endif
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* If the file was just truncated to a size smaller than the currently
+ ** mapped region, reduce the effective mapping size as well. SQLite will
+ ** use read() and write() to access data beyond this point from now on.
+ */
+ if( nBytemmapSize ){
+ pFile->mmapSize = nByte;
+ }
+#endif
+
+ return SQLITE_OK;
+ }
+}
+
+/*
+** Determine the current size of a file in bytes
+*/
+static int unixFileSize(sqlite3_file *id, i64 *pSize){
+ int rc;
+ struct stat buf;
+ assert( id );
+ rc = osFstat(((unixFile*)id)->h, &buf);
+ SimulateIOError( rc=1 );
+ if( rc!=0 ){
+ storeLastErrno((unixFile*)id, errno);
+ return SQLITE_IOERR_FSTAT;
+ }
+ *pSize = buf.st_size;
+
+ /* When opening a zero-size database, the findInodeInfo() procedure
+ ** writes a single byte into that file in order to work around a bug
+ ** in the OS-X msdos filesystem. In order to avoid problems with upper
+ ** layers, we need to report this file size as zero even though it is
+ ** really 1. Ticket #3260.
+ */
+ if( *pSize==1 ) *pSize = 0;
+
+
+ return SQLITE_OK;
+}
+
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+/*
+** Handler for proxy-locking file-control verbs. Defined below in the
+** proxying locking division.
+*/
+static int proxyFileControl(sqlite3_file*,int,void*);
+#endif
+
+/*
+** This function is called to handle the SQLITE_FCNTL_SIZE_HINT
+** file-control operation. Enlarge the database to nBytes in size
+** (rounded up to the next chunk-size). If the database is already
+** nBytes or larger, this routine is a no-op.
+*/
+static int fcntlSizeHint(unixFile *pFile, i64 nByte){
+ if( pFile->szChunk>0 ){
+ i64 nSize; /* Required file size */
+ struct stat buf; /* Used to hold return values of fstat() */
+
+ if( osFstat(pFile->h, &buf) ){
+ return SQLITE_IOERR_FSTAT;
+ }
+
+ nSize = ((nByte+pFile->szChunk-1) / pFile->szChunk) * pFile->szChunk;
+ if( nSize>(i64)buf.st_size ){
+
+#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
+ /* The code below is handling the return value of osFallocate()
+ ** correctly. posix_fallocate() is defined to "returns zero on success,
+ ** or an error number on failure". See the manpage for details. */
+ int err;
+ do{
+ err = osFallocate(pFile->h, buf.st_size, nSize-buf.st_size);
+ }while( err==EINTR );
+ if( err && err!=EINVAL ) return SQLITE_IOERR_WRITE;
+#else
+ /* If the OS does not have posix_fallocate(), fake it. Write a
+ ** single byte to the last byte in each block that falls entirely
+ ** within the extended region. Then, if required, a single byte
+ ** at offset (nSize-1), to set the size of the file correctly.
+ ** This is a similar technique to that used by glibc on systems
+ ** that do not have a real fallocate() call.
+ */
+ int nBlk = buf.st_blksize; /* File-system block size */
+ int nWrite = 0; /* Number of bytes written by seekAndWrite */
+ i64 iWrite; /* Next offset to write to */
+
+ iWrite = (buf.st_size/nBlk)*nBlk + nBlk - 1;
+ assert( iWrite>=buf.st_size );
+ assert( ((iWrite+1)%nBlk)==0 );
+ for(/*no-op*/; iWrite=nSize ) iWrite = nSize - 1;
+ nWrite = seekAndWrite(pFile, iWrite, "", 1);
+ if( nWrite!=1 ) return SQLITE_IOERR_WRITE;
+ }
+#endif
+ }
+ }
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ if( pFile->mmapSizeMax>0 && nByte>pFile->mmapSize ){
+ int rc;
+ if( pFile->szChunk<=0 ){
+ if( robust_ftruncate(pFile->h, nByte) ){
+ storeLastErrno(pFile, errno);
+ return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
+ }
+ }
+
+ rc = unixMapfile(pFile, nByte);
+ return rc;
+ }
+#endif
+
+ return SQLITE_OK;
+}
+
+/*
+** If *pArg is initially negative then this is a query. Set *pArg to
+** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
+**
+** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
+*/
+static void unixModeBit(unixFile *pFile, unsigned char mask, int *pArg){
+ if( *pArg<0 ){
+ *pArg = (pFile->ctrlFlags & mask)!=0;
+ }else if( (*pArg)==0 ){
+ pFile->ctrlFlags &= ~mask;
+ }else{
+ pFile->ctrlFlags |= mask;
+ }
+}
+
+/* Forward declaration */
+static int unixGetTempname(int nBuf, char *zBuf);
+
+/*
+** Information and control of an open file handle.
+*/
+static int unixFileControl(sqlite3_file *id, int op, void *pArg){
+ unixFile *pFile = (unixFile*)id;
+ switch( op ){
+#if defined(__linux__) && defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
+ case SQLITE_FCNTL_BEGIN_ATOMIC_WRITE: {
+ int rc = osIoctl(pFile->h, F2FS_IOC_START_ATOMIC_WRITE);
+ return rc ? SQLITE_IOERR_BEGIN_ATOMIC : SQLITE_OK;
+ }
+ case SQLITE_FCNTL_COMMIT_ATOMIC_WRITE: {
+ int rc = osIoctl(pFile->h, F2FS_IOC_COMMIT_ATOMIC_WRITE);
+ return rc ? SQLITE_IOERR_COMMIT_ATOMIC : SQLITE_OK;
+ }
+ case SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE: {
+ int rc = osIoctl(pFile->h, F2FS_IOC_ABORT_VOLATILE_WRITE);
+ return rc ? SQLITE_IOERR_ROLLBACK_ATOMIC : SQLITE_OK;
+ }
+#endif /* __linux__ && SQLITE_ENABLE_BATCH_ATOMIC_WRITE */
+
+ case SQLITE_FCNTL_LOCKSTATE: {
+ *(int*)pArg = pFile->eFileLock;
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_LAST_ERRNO: {
+ *(int*)pArg = pFile->lastErrno;
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_CHUNK_SIZE: {
+ pFile->szChunk = *(int *)pArg;
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_SIZE_HINT: {
+ int rc;
+ SimulateIOErrorBenign(1);
+ rc = fcntlSizeHint(pFile, *(i64 *)pArg);
+ SimulateIOErrorBenign(0);
+ return rc;
+ }
+ case SQLITE_FCNTL_PERSIST_WAL: {
+ unixModeBit(pFile, UNIXFILE_PERSIST_WAL, (int*)pArg);
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
+ unixModeBit(pFile, UNIXFILE_PSOW, (int*)pArg);
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_VFSNAME: {
+ *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_TEMPFILENAME: {
+ char *zTFile = sqlite3_malloc64( pFile->pVfs->mxPathname );
+ if( zTFile ){
+ unixGetTempname(pFile->pVfs->mxPathname, zTFile);
+ *(char**)pArg = zTFile;
+ }
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_HAS_MOVED: {
+ *(int*)pArg = fileHasMoved(pFile);
+ return SQLITE_OK;
+ }
+#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
+ case SQLITE_FCNTL_LOCK_TIMEOUT: {
+ pFile->iBusyTimeout = *(int*)pArg;
+ return SQLITE_OK;
+ }
+#endif
+#if SQLITE_MAX_MMAP_SIZE>0
+ case SQLITE_FCNTL_MMAP_SIZE: {
+ i64 newLimit = *(i64*)pArg;
+ int rc = SQLITE_OK;
+ if( newLimit>sqlite3GlobalConfig.mxMmap ){
+ newLimit = sqlite3GlobalConfig.mxMmap;
+ }
+
+ /* The value of newLimit may be eventually cast to (size_t) and passed
+ ** to mmap(). Restrict its value to 2GB if (size_t) is not at least a
+ ** 64-bit type. */
+ if( newLimit>0 && sizeof(size_t)<8 ){
+ newLimit = (newLimit & 0x7FFFFFFF);
+ }
+
+ *(i64*)pArg = pFile->mmapSizeMax;
+ if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
+ pFile->mmapSizeMax = newLimit;
+ if( pFile->mmapSize>0 ){
+ unixUnmapfile(pFile);
+ rc = unixMapfile(pFile, -1);
+ }
+ }
+ return rc;
+ }
+#endif
+#ifdef SQLITE_DEBUG
+ /* The pager calls this method to signal that it has done
+ ** a rollback and that the database is therefore unchanged and
+ ** it hence it is OK for the transaction change counter to be
+ ** unchanged.
+ */
+ case SQLITE_FCNTL_DB_UNCHANGED: {
+ ((unixFile*)id)->dbUpdate = 0;
+ return SQLITE_OK;
+ }
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+ case SQLITE_FCNTL_SET_LOCKPROXYFILE:
+ case SQLITE_FCNTL_GET_LOCKPROXYFILE: {
+ return proxyFileControl(id,op,pArg);
+ }
+#endif /* SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__) */
+ }
+ return SQLITE_NOTFOUND;
+}
+
+/*
+** If pFd->sectorSize is non-zero when this function is called, it is a
+** no-op. Otherwise, the values of pFd->sectorSize and
+** pFd->deviceCharacteristics are set according to the file-system
+** characteristics.
+**
+** There are two versions of this function. One for QNX and one for all
+** other systems.
+*/
+#ifndef __QNXNTO__
+static void setDeviceCharacteristics(unixFile *pFd){
+ assert( pFd->deviceCharacteristics==0 || pFd->sectorSize!=0 );
+ if( pFd->sectorSize==0 ){
+#if defined(__linux__) && defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
+ int res;
+ u32 f = 0;
+
+ /* Check for support for F2FS atomic batch writes. */
+ res = osIoctl(pFd->h, F2FS_IOC_GET_FEATURES, &f);
+ if( res==0 && (f & F2FS_FEATURE_ATOMIC_WRITE) ){
+ pFd->deviceCharacteristics = SQLITE_IOCAP_BATCH_ATOMIC;
+ }
+#endif /* __linux__ && SQLITE_ENABLE_BATCH_ATOMIC_WRITE */
+
+ /* Set the POWERSAFE_OVERWRITE flag if requested. */
+ if( pFd->ctrlFlags & UNIXFILE_PSOW ){
+ pFd->deviceCharacteristics |= SQLITE_IOCAP_POWERSAFE_OVERWRITE;
+ }
+
+ pFd->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
+ }
+}
+#else
+#include
+#include
+static void setDeviceCharacteristics(unixFile *pFile){
+ if( pFile->sectorSize == 0 ){
+ struct statvfs fsInfo;
+
+ /* Set defaults for non-supported filesystems */
+ pFile->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
+ pFile->deviceCharacteristics = 0;
+ if( fstatvfs(pFile->h, &fsInfo) == -1 ) {
+ return;
+ }
+
+ if( !strcmp(fsInfo.f_basetype, "tmp") ) {
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ SQLITE_IOCAP_ATOMIC4K | /* All ram filesystem writes are atomic */
+ SQLITE_IOCAP_SAFE_APPEND | /* growing the file does not occur until
+ ** the write succeeds */
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else if( strstr(fsInfo.f_basetype, "etfs") ){
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ /* etfs cluster size writes are atomic */
+ (pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) |
+ SQLITE_IOCAP_SAFE_APPEND | /* growing the file does not occur until
+ ** the write succeeds */
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else if( !strcmp(fsInfo.f_basetype, "qnx6") ){
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ SQLITE_IOCAP_ATOMIC | /* All filesystem writes are atomic */
+ SQLITE_IOCAP_SAFE_APPEND | /* growing the file does not occur until
+ ** the write succeeds */
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else if( !strcmp(fsInfo.f_basetype, "qnx4") ){
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ /* full bitset of atomics from max sector size and smaller */
+ ((pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) << 1) - 2 |
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else if( strstr(fsInfo.f_basetype, "dos") ){
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ /* full bitset of atomics from max sector size and smaller */
+ ((pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) << 1) - 2 |
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else{
+ pFile->deviceCharacteristics =
+ SQLITE_IOCAP_ATOMIC512 | /* blocks are atomic */
+ SQLITE_IOCAP_SAFE_APPEND | /* growing the file does not occur until
+ ** the write succeeds */
+ 0;
+ }
+ }
+ /* Last chance verification. If the sector size isn't a multiple of 512
+ ** then it isn't valid.*/
+ if( pFile->sectorSize % 512 != 0 ){
+ pFile->deviceCharacteristics = 0;
+ pFile->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
+ }
+}
+#endif
+
+/*
+** Return the sector size in bytes of the underlying block device for
+** the specified file. This is almost always 512 bytes, but may be
+** larger for some devices.
+**
+** SQLite code assumes this function cannot fail. It also assumes that
+** if two files are created in the same file-system directory (i.e.
+** a database and its journal file) that the sector size will be the
+** same for both.
+*/
+static int unixSectorSize(sqlite3_file *id){
+ unixFile *pFd = (unixFile*)id;
+ setDeviceCharacteristics(pFd);
+ return pFd->sectorSize;
+}
+
+/*
+** Return the device characteristics for the file.
+**
+** This VFS is set up to return SQLITE_IOCAP_POWERSAFE_OVERWRITE by default.
+** However, that choice is controversial since technically the underlying
+** file system does not always provide powersafe overwrites. (In other
+** words, after a power-loss event, parts of the file that were never
+** written might end up being altered.) However, non-PSOW behavior is very,
+** very rare. And asserting PSOW makes a large reduction in the amount
+** of required I/O for journaling, since a lot of padding is eliminated.
+** Hence, while POWERSAFE_OVERWRITE is on by default, there is a file-control
+** available to turn it off and URI query parameter available to turn it off.
+*/
+static int unixDeviceCharacteristics(sqlite3_file *id){
+ unixFile *pFd = (unixFile*)id;
+ setDeviceCharacteristics(pFd);
+ return pFd->deviceCharacteristics;
+}
+
+#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
+
+/*
+** Return the system page size.
+**
+** This function should not be called directly by other code in this file.
+** Instead, it should be called via macro osGetpagesize().
+*/
+static int unixGetpagesize(void){
+#if OS_VXWORKS
+ return 1024;
+#elif defined(_BSD_SOURCE)
+ return getpagesize();
+#else
+ return (int)sysconf(_SC_PAGESIZE);
+#endif
+}
+
+#endif /* !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0 */
+
+#ifndef SQLITE_OMIT_WAL
+
+/*
+** Object used to represent an shared memory buffer.
+**
+** When multiple threads all reference the same wal-index, each thread
+** has its own unixShm object, but they all point to a single instance
+** of this unixShmNode object. In other words, each wal-index is opened
+** only once per process.
+**
+** Each unixShmNode object is connected to a single unixInodeInfo object.
+** We could coalesce this object into unixInodeInfo, but that would mean
+** every open file that does not use shared memory (in other words, most
+** open files) would have to carry around this extra information. So
+** the unixInodeInfo object contains a pointer to this unixShmNode object
+** and the unixShmNode object is created only when needed.
+**
+** unixMutexHeld() must be true when creating or destroying
+** this object or while reading or writing the following fields:
+**
+** nRef
+**
+** The following fields are read-only after the object is created:
+**
+** fid
+** zFilename
+**
+** Either unixShmNode.mutex must be held or unixShmNode.nRef==0 and
+** unixMutexHeld() is true when reading or writing any other field
+** in this structure.
+*/
+struct unixShmNode {
+ unixInodeInfo *pInode; /* unixInodeInfo that owns this SHM node */
+ sqlite3_mutex *mutex; /* Mutex to access this object */
+ char *zFilename; /* Name of the mmapped file */
+ int h; /* Open file descriptor */
+ int szRegion; /* Size of shared-memory regions */
+ u16 nRegion; /* Size of array apRegion */
+ u8 isReadonly; /* True if read-only */
+ u8 isUnlocked; /* True if no DMS lock held */
+ char **apRegion; /* Array of mapped shared-memory regions */
+ int nRef; /* Number of unixShm objects pointing to this */
+ unixShm *pFirst; /* All unixShm objects pointing to this */
+#ifdef SQLITE_DEBUG
+ u8 exclMask; /* Mask of exclusive locks held */
+ u8 sharedMask; /* Mask of shared locks held */
+ u8 nextShmId; /* Next available unixShm.id value */
+#endif
+};
+
+/*
+** Structure used internally by this VFS to record the state of an
+** open shared memory connection.
+**
+** The following fields are initialized when this object is created and
+** are read-only thereafter:
+**
+** unixShm.pFile
+** unixShm.id
+**
+** All other fields are read/write. The unixShm.pFile->mutex must be held
+** while accessing any read/write fields.
+*/
+struct unixShm {
+ unixShmNode *pShmNode; /* The underlying unixShmNode object */
+ unixShm *pNext; /* Next unixShm with the same unixShmNode */
+ u8 hasMutex; /* True if holding the unixShmNode mutex */
+ u8 id; /* Id of this connection within its unixShmNode */
+ u16 sharedMask; /* Mask of shared locks held */
+ u16 exclMask; /* Mask of exclusive locks held */
+};
+
+/*
+** Constants used for locking
+*/
+#define UNIX_SHM_BASE ((22+SQLITE_SHM_NLOCK)*4) /* first lock byte */
+#define UNIX_SHM_DMS (UNIX_SHM_BASE+SQLITE_SHM_NLOCK) /* deadman switch */
+
+/*
+** Apply posix advisory locks for all bytes from ofst through ofst+n-1.
+**
+** Locks block if the mask is exactly UNIX_SHM_C and are non-blocking
+** otherwise.
+*/
+static int unixShmSystemLock(
+ unixFile *pFile, /* Open connection to the WAL file */
+ int lockType, /* F_UNLCK, F_RDLCK, or F_WRLCK */
+ int ofst, /* First byte of the locking range */
+ int n /* Number of bytes to lock */
+){
+ unixShmNode *pShmNode; /* Apply locks to this open shared-memory segment */
+ struct flock f; /* The posix advisory locking structure */
+ int rc = SQLITE_OK; /* Result code form fcntl() */
+
+ /* Access to the unixShmNode object is serialized by the caller */
+ pShmNode = pFile->pInode->pShmNode;
+ assert( pShmNode->nRef==0 || sqlite3_mutex_held(pShmNode->mutex) );
+
+ /* Shared locks never span more than one byte */
+ assert( n==1 || lockType!=F_RDLCK );
+
+ /* Locks are within range */
+ assert( n>=1 && n<=SQLITE_SHM_NLOCK );
+
+ if( pShmNode->h>=0 ){
+ /* Initialize the locking parameters */
+ f.l_type = lockType;
+ f.l_whence = SEEK_SET;
+ f.l_start = ofst;
+ f.l_len = n;
+ rc = osSetPosixAdvisoryLock(pShmNode->h, &f, pFile);
+ rc = (rc!=(-1)) ? SQLITE_OK : SQLITE_BUSY;
+ }
+
+ /* Update the global lock state and do debug tracing */
+#ifdef SQLITE_DEBUG
+ { u16 mask;
+ OSTRACE(("SHM-LOCK "));
+ mask = ofst>31 ? 0xffff : (1<<(ofst+n)) - (1<exclMask &= ~mask;
+ pShmNode->sharedMask &= ~mask;
+ }else if( lockType==F_RDLCK ){
+ OSTRACE(("read-lock %d ok", ofst));
+ pShmNode->exclMask &= ~mask;
+ pShmNode->sharedMask |= mask;
+ }else{
+ assert( lockType==F_WRLCK );
+ OSTRACE(("write-lock %d ok", ofst));
+ pShmNode->exclMask |= mask;
+ pShmNode->sharedMask &= ~mask;
+ }
+ }else{
+ if( lockType==F_UNLCK ){
+ OSTRACE(("unlock %d failed", ofst));
+ }else if( lockType==F_RDLCK ){
+ OSTRACE(("read-lock failed"));
+ }else{
+ assert( lockType==F_WRLCK );
+ OSTRACE(("write-lock %d failed", ofst));
+ }
+ }
+ OSTRACE((" - afterwards %03x,%03x\n",
+ pShmNode->sharedMask, pShmNode->exclMask));
+ }
+#endif
+
+ return rc;
+}
+
+/*
+** Return the minimum number of 32KB shm regions that should be mapped at
+** a time, assuming that each mapping must be an integer multiple of the
+** current system page-size.
+**
+** Usually, this is 1. The exception seems to be systems that are configured
+** to use 64KB pages - in this case each mapping must cover at least two
+** shm regions.
+*/
+static int unixShmRegionPerMap(void){
+ int shmsz = 32*1024; /* SHM region size */
+ int pgsz = osGetpagesize(); /* System page size */
+ assert( ((pgsz-1)&pgsz)==0 ); /* Page size must be a power of 2 */
+ if( pgszpInode->pShmNode;
+ assert( unixMutexHeld() );
+ if( p && ALWAYS(p->nRef==0) ){
+ int nShmPerMap = unixShmRegionPerMap();
+ int i;
+ assert( p->pInode==pFd->pInode );
+ sqlite3_mutex_free(p->mutex);
+ for(i=0; inRegion; i+=nShmPerMap){
+ if( p->h>=0 ){
+ osMunmap(p->apRegion[i], p->szRegion);
+ }else{
+ sqlite3_free(p->apRegion[i]);
+ }
+ }
+ sqlite3_free(p->apRegion);
+ if( p->h>=0 ){
+ robust_close(pFd, p->h, __LINE__);
+ p->h = -1;
+ }
+ p->pInode->pShmNode = 0;
+ sqlite3_free(p);
+ }
+}
+
+/*
+** The DMS lock has not yet been taken on shm file pShmNode. Attempt to
+** take it now. Return SQLITE_OK if successful, or an SQLite error
+** code otherwise.
+**
+** If the DMS cannot be locked because this is a readonly_shm=1
+** connection and no other process already holds a lock, return
+** SQLITE_READONLY_CANTINIT and set pShmNode->isUnlocked=1.
+*/
+static int unixLockSharedMemory(unixFile *pDbFd, unixShmNode *pShmNode){
+ struct flock lock;
+ int rc = SQLITE_OK;
+
+ /* Use F_GETLK to determine the locks other processes are holding
+ ** on the DMS byte. If it indicates that another process is holding
+ ** a SHARED lock, then this process may also take a SHARED lock
+ ** and proceed with opening the *-shm file.
+ **
+ ** Or, if no other process is holding any lock, then this process
+ ** is the first to open it. In this case take an EXCLUSIVE lock on the
+ ** DMS byte and truncate the *-shm file to zero bytes in size. Then
+ ** downgrade to a SHARED lock on the DMS byte.
+ **
+ ** If another process is holding an EXCLUSIVE lock on the DMS byte,
+ ** return SQLITE_BUSY to the caller (it will try again). An earlier
+ ** version of this code attempted the SHARED lock at this point. But
+ ** this introduced a subtle race condition: if the process holding
+ ** EXCLUSIVE failed just before truncating the *-shm file, then this
+ ** process might open and use the *-shm file without truncating it.
+ ** And if the *-shm file has been corrupted by a power failure or
+ ** system crash, the database itself may also become corrupt. */
+ lock.l_whence = SEEK_SET;
+ lock.l_start = UNIX_SHM_DMS;
+ lock.l_len = 1;
+ lock.l_type = F_WRLCK;
+ if( osFcntl(pShmNode->h, F_GETLK, &lock)!=0 ) {
+ rc = SQLITE_IOERR_LOCK;
+ }else if( lock.l_type==F_UNLCK ){
+ if( pShmNode->isReadonly ){
+ pShmNode->isUnlocked = 1;
+ rc = SQLITE_READONLY_CANTINIT;
+ }else{
+ rc = unixShmSystemLock(pDbFd, F_WRLCK, UNIX_SHM_DMS, 1);
+ if( rc==SQLITE_OK && robust_ftruncate(pShmNode->h, 0) ){
+ rc = unixLogError(SQLITE_IOERR_SHMOPEN,"ftruncate",pShmNode->zFilename);
+ }
+ }
+ }else if( lock.l_type==F_WRLCK ){
+ rc = SQLITE_BUSY;
+ }
+
+ if( rc==SQLITE_OK ){
+ assert( lock.l_type==F_UNLCK || lock.l_type==F_RDLCK );
+ rc = unixShmSystemLock(pDbFd, F_RDLCK, UNIX_SHM_DMS, 1);
+ }
+ return rc;
+}
+
+/*
+** Open a shared-memory area associated with open database file pDbFd.
+** This particular implementation uses mmapped files.
+**
+** The file used to implement shared-memory is in the same directory
+** as the open database file and has the same name as the open database
+** file with the "-shm" suffix added. For example, if the database file
+** is "/home/user1/config.db" then the file that is created and mmapped
+** for shared memory will be called "/home/user1/config.db-shm".
+**
+** Another approach to is to use files in /dev/shm or /dev/tmp or an
+** some other tmpfs mount. But if a file in a different directory
+** from the database file is used, then differing access permissions
+** or a chroot() might cause two different processes on the same
+** database to end up using different files for shared memory -
+** meaning that their memory would not really be shared - resulting
+** in database corruption. Nevertheless, this tmpfs file usage
+** can be enabled at compile-time using -DSQLITE_SHM_DIRECTORY="/dev/shm"
+** or the equivalent. The use of the SQLITE_SHM_DIRECTORY compile-time
+** option results in an incompatible build of SQLite; builds of SQLite
+** that with differing SQLITE_SHM_DIRECTORY settings attempt to use the
+** same database file at the same time, database corruption will likely
+** result. The SQLITE_SHM_DIRECTORY compile-time option is considered
+** "unsupported" and may go away in a future SQLite release.
+**
+** When opening a new shared-memory file, if no other instances of that
+** file are currently open, in this process or in other processes, then
+** the file must be truncated to zero length or have its header cleared.
+**
+** If the original database file (pDbFd) is using the "unix-excl" VFS
+** that means that an exclusive lock is held on the database file and
+** that no other processes are able to read or write the database. In
+** that case, we do not really need shared memory. No shared memory
+** file is created. The shared memory will be simulated with heap memory.
+*/
+static int unixOpenSharedMemory(unixFile *pDbFd){
+ struct unixShm *p = 0; /* The connection to be opened */
+ struct unixShmNode *pShmNode; /* The underlying mmapped file */
+ int rc = SQLITE_OK; /* Result code */
+ unixInodeInfo *pInode; /* The inode of fd */
+ char *zShm; /* Name of the file used for SHM */
+ int nShmFilename; /* Size of the SHM filename in bytes */
+
+ /* Allocate space for the new unixShm object. */
+ p = sqlite3_malloc64( sizeof(*p) );
+ if( p==0 ) return SQLITE_NOMEM_BKPT;
+ memset(p, 0, sizeof(*p));
+ assert( pDbFd->pShm==0 );
+
+ /* Check to see if a unixShmNode object already exists. Reuse an existing
+ ** one if present. Create a new one if necessary.
+ */
+ assert( unixFileMutexNotheld(pDbFd) );
+ unixEnterMutex();
+ pInode = pDbFd->pInode;
+ pShmNode = pInode->pShmNode;
+ if( pShmNode==0 ){
+ struct stat sStat; /* fstat() info for database file */
+#ifndef SQLITE_SHM_DIRECTORY
+ const char *zBasePath = pDbFd->zPath;
+#endif
+
+ /* Call fstat() to figure out the permissions on the database file. If
+ ** a new *-shm file is created, an attempt will be made to create it
+ ** with the same permissions.
+ */
+ if( osFstat(pDbFd->h, &sStat) ){
+ rc = SQLITE_IOERR_FSTAT;
+ goto shm_open_err;
+ }
+
+#ifdef SQLITE_SHM_DIRECTORY
+ nShmFilename = sizeof(SQLITE_SHM_DIRECTORY) + 31;
+#else
+ nShmFilename = 6 + (int)strlen(zBasePath);
+#endif
+ pShmNode = sqlite3_malloc64( sizeof(*pShmNode) + nShmFilename );
+ if( pShmNode==0 ){
+ rc = SQLITE_NOMEM_BKPT;
+ goto shm_open_err;
+ }
+ memset(pShmNode, 0, sizeof(*pShmNode)+nShmFilename);
+ zShm = pShmNode->zFilename = (char*)&pShmNode[1];
+#ifdef SQLITE_SHM_DIRECTORY
+ sqlite3_snprintf(nShmFilename, zShm,
+ SQLITE_SHM_DIRECTORY "/sqlite-shm-%x-%x",
+ (u32)sStat.st_ino, (u32)sStat.st_dev);
+#else
+ sqlite3_snprintf(nShmFilename, zShm, "%s-shm", zBasePath);
+ sqlite3FileSuffix3(pDbFd->zPath, zShm);
+#endif
+ pShmNode->h = -1;
+ pDbFd->pInode->pShmNode = pShmNode;
+ pShmNode->pInode = pDbFd->pInode;
+ if( sqlite3GlobalConfig.bCoreMutex ){
+ pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
+ if( pShmNode->mutex==0 ){
+ rc = SQLITE_NOMEM_BKPT;
+ goto shm_open_err;
+ }
+ }
+
+ if( pInode->bProcessLock==0 ){
+ if( 0==sqlite3_uri_boolean(pDbFd->zPath, "readonly_shm", 0) ){
+ pShmNode->h = robust_open(zShm, O_RDWR|O_CREAT, (sStat.st_mode&0777));
+ }
+ if( pShmNode->h<0 ){
+ pShmNode->h = robust_open(zShm, O_RDONLY, (sStat.st_mode&0777));
+ if( pShmNode->h<0 ){
+ rc = unixLogError(SQLITE_CANTOPEN_BKPT, "open", zShm);
+ goto shm_open_err;
+ }
+ pShmNode->isReadonly = 1;
+ }
+
+ /* If this process is running as root, make sure that the SHM file
+ ** is owned by the same user that owns the original database. Otherwise,
+ ** the original owner will not be able to connect.
+ */
+ robustFchown(pShmNode->h, sStat.st_uid, sStat.st_gid);
+
+ rc = unixLockSharedMemory(pDbFd, pShmNode);
+ if( rc!=SQLITE_OK && rc!=SQLITE_READONLY_CANTINIT ) goto shm_open_err;
+ }
+ }
+
+ /* Make the new connection a child of the unixShmNode */
+ p->pShmNode = pShmNode;
+#ifdef SQLITE_DEBUG
+ p->id = pShmNode->nextShmId++;
+#endif
+ pShmNode->nRef++;
+ pDbFd->pShm = p;
+ unixLeaveMutex();
+
+ /* The reference count on pShmNode has already been incremented under
+ ** the cover of the unixEnterMutex() mutex and the pointer from the
+ ** new (struct unixShm) object to the pShmNode has been set. All that is
+ ** left to do is to link the new object into the linked list starting
+ ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex
+ ** mutex.
+ */
+ sqlite3_mutex_enter(pShmNode->mutex);
+ p->pNext = pShmNode->pFirst;
+ pShmNode->pFirst = p;
+ sqlite3_mutex_leave(pShmNode->mutex);
+ return rc;
+
+ /* Jump here on any error */
+shm_open_err:
+ unixShmPurge(pDbFd); /* This call frees pShmNode if required */
+ sqlite3_free(p);
+ unixLeaveMutex();
+ return rc;
+}
+
+/*
+** This function is called to obtain a pointer to region iRegion of the
+** shared-memory associated with the database file fd. Shared-memory regions
+** are numbered starting from zero. Each shared-memory region is szRegion
+** bytes in size.
+**
+** If an error occurs, an error code is returned and *pp is set to NULL.
+**
+** Otherwise, if the bExtend parameter is 0 and the requested shared-memory
+** region has not been allocated (by any client, including one running in a
+** separate process), then *pp is set to NULL and SQLITE_OK returned. If
+** bExtend is non-zero and the requested shared-memory region has not yet
+** been allocated, it is allocated by this function.
+**
+** If the shared-memory region has already been allocated or is allocated by
+** this call as described above, then it is mapped into this processes
+** address space (if it is not already), *pp is set to point to the mapped
+** memory and SQLITE_OK returned.
+*/
+static int unixShmMap(
+ sqlite3_file *fd, /* Handle open on database file */
+ int iRegion, /* Region to retrieve */
+ int szRegion, /* Size of regions */
+ int bExtend, /* True to extend file if necessary */
+ void volatile **pp /* OUT: Mapped memory */
+){
+ unixFile *pDbFd = (unixFile*)fd;
+ unixShm *p;
+ unixShmNode *pShmNode;
+ int rc = SQLITE_OK;
+ int nShmPerMap = unixShmRegionPerMap();
+ int nReqRegion;
+
+ /* If the shared-memory file has not yet been opened, open it now. */
+ if( pDbFd->pShm==0 ){
+ rc = unixOpenSharedMemory(pDbFd);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+
+ p = pDbFd->pShm;
+ pShmNode = p->pShmNode;
+ sqlite3_mutex_enter(pShmNode->mutex);
+ if( pShmNode->isUnlocked ){
+ rc = unixLockSharedMemory(pDbFd, pShmNode);
+ if( rc!=SQLITE_OK ) goto shmpage_out;
+ pShmNode->isUnlocked = 0;
+ }
+ assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
+ assert( pShmNode->pInode==pDbFd->pInode );
+ assert( pShmNode->h>=0 || pDbFd->pInode->bProcessLock==1 );
+ assert( pShmNode->h<0 || pDbFd->pInode->bProcessLock==0 );
+
+ /* Minimum number of regions required to be mapped. */
+ nReqRegion = ((iRegion+nShmPerMap) / nShmPerMap) * nShmPerMap;
+
+ if( pShmNode->nRegionszRegion = szRegion;
+
+ if( pShmNode->h>=0 ){
+ /* The requested region is not mapped into this processes address space.
+ ** Check to see if it has been allocated (i.e. if the wal-index file is
+ ** large enough to contain the requested region).
+ */
+ if( osFstat(pShmNode->h, &sStat) ){
+ rc = SQLITE_IOERR_SHMSIZE;
+ goto shmpage_out;
+ }
+
+ if( sStat.st_sizeh, iPg*pgsz + pgsz-1, "", 1, &x)!=1 ){
+ const char *zFile = pShmNode->zFilename;
+ rc = unixLogError(SQLITE_IOERR_SHMSIZE, "write", zFile);
+ goto shmpage_out;
+ }
+ }
+ }
+ }
+ }
+
+ /* Map the requested memory region into this processes address space. */
+ apNew = (char **)sqlite3_realloc(
+ pShmNode->apRegion, nReqRegion*sizeof(char *)
+ );
+ if( !apNew ){
+ rc = SQLITE_IOERR_NOMEM_BKPT;
+ goto shmpage_out;
+ }
+ pShmNode->apRegion = apNew;
+ while( pShmNode->nRegionh>=0 ){
+ pMem = osMmap(0, nMap,
+ pShmNode->isReadonly ? PROT_READ : PROT_READ|PROT_WRITE,
+ MAP_SHARED, pShmNode->h, szRegion*(i64)pShmNode->nRegion
+ );
+ if( pMem==MAP_FAILED ){
+ rc = unixLogError(SQLITE_IOERR_SHMMAP, "mmap", pShmNode->zFilename);
+ goto shmpage_out;
+ }
+ }else{
+ pMem = sqlite3_malloc64(szRegion);
+ if( pMem==0 ){
+ rc = SQLITE_NOMEM_BKPT;
+ goto shmpage_out;
+ }
+ memset(pMem, 0, szRegion);
+ }
+
+ for(i=0; iapRegion[pShmNode->nRegion+i] = &((char*)pMem)[szRegion*i];
+ }
+ pShmNode->nRegion += nShmPerMap;
+ }
+ }
+
+shmpage_out:
+ if( pShmNode->nRegion>iRegion ){
+ *pp = pShmNode->apRegion[iRegion];
+ }else{
+ *pp = 0;
+ }
+ if( pShmNode->isReadonly && rc==SQLITE_OK ) rc = SQLITE_READONLY;
+ sqlite3_mutex_leave(pShmNode->mutex);
+ return rc;
+}
+
+/*
+** Change the lock state for a shared-memory segment.
+**
+** Note that the relationship between SHAREd and EXCLUSIVE locks is a little
+** different here than in posix. In xShmLock(), one can go from unlocked
+** to shared and back or from unlocked to exclusive and back. But one may
+** not go from shared to exclusive or from exclusive to shared.
+*/
+static int unixShmLock(
+ sqlite3_file *fd, /* Database file holding the shared memory */
+ int ofst, /* First lock to acquire or release */
+ int n, /* Number of locks to acquire or release */
+ int flags /* What to do with the lock */
+){
+ unixFile *pDbFd = (unixFile*)fd; /* Connection holding shared memory */
+ unixShm *p = pDbFd->pShm; /* The shared memory being locked */
+ unixShm *pX; /* For looping over all siblings */
+ unixShmNode *pShmNode = p->pShmNode; /* The underlying file iNode */
+ int rc = SQLITE_OK; /* Result code */
+ u16 mask; /* Mask of locks to take or release */
+
+ assert( pShmNode==pDbFd->pInode->pShmNode );
+ assert( pShmNode->pInode==pDbFd->pInode );
+ assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
+ assert( n>=1 );
+ assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
+ assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
+ assert( pShmNode->h>=0 || pDbFd->pInode->bProcessLock==1 );
+ assert( pShmNode->h<0 || pDbFd->pInode->bProcessLock==0 );
+
+ mask = (1<<(ofst+n)) - (1<1 || mask==(1<mutex);
+ if( flags & SQLITE_SHM_UNLOCK ){
+ u16 allMask = 0; /* Mask of locks held by siblings */
+
+ /* See if any siblings hold this same lock */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( pX==p ) continue;
+ assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
+ allMask |= pX->sharedMask;
+ }
+
+ /* Unlock the system-level locks */
+ if( (mask & allMask)==0 ){
+ rc = unixShmSystemLock(pDbFd, F_UNLCK, ofst+UNIX_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+
+ /* Undo the local locks */
+ if( rc==SQLITE_OK ){
+ p->exclMask &= ~mask;
+ p->sharedMask &= ~mask;
+ }
+ }else if( flags & SQLITE_SHM_SHARED ){
+ u16 allShared = 0; /* Union of locks held by connections other than "p" */
+
+ /* Find out which shared locks are already held by sibling connections.
+ ** If any sibling already holds an exclusive lock, go ahead and return
+ ** SQLITE_BUSY.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ allShared |= pX->sharedMask;
+ }
+
+ /* Get shared locks at the system level, if necessary */
+ if( rc==SQLITE_OK ){
+ if( (allShared & mask)==0 ){
+ rc = unixShmSystemLock(pDbFd, F_RDLCK, ofst+UNIX_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+ }
+
+ /* Get the local shared locks */
+ if( rc==SQLITE_OK ){
+ p->sharedMask |= mask;
+ }
+ }else{
+ /* Make sure no sibling connections hold locks that will block this
+ ** lock. If any do, return SQLITE_BUSY right away.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ }
+
+ /* Get the exclusive locks at the system level. Then if successful
+ ** also mark the local connection as being locked.
+ */
+ if( rc==SQLITE_OK ){
+ rc = unixShmSystemLock(pDbFd, F_WRLCK, ofst+UNIX_SHM_BASE, n);
+ if( rc==SQLITE_OK ){
+ assert( (p->sharedMask & mask)==0 );
+ p->exclMask |= mask;
+ }
+ }
+ }
+ sqlite3_mutex_leave(pShmNode->mutex);
+ OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x\n",
+ p->id, osGetpid(0), p->sharedMask, p->exclMask));
+ return rc;
+}
+
+/*
+** Implement a memory barrier or memory fence on shared memory.
+**
+** All loads and stores begun before the barrier must complete before
+** any load or store begun after the barrier.
+*/
+static void unixShmBarrier(
+ sqlite3_file *fd /* Database file holding the shared memory */
+){
+ UNUSED_PARAMETER(fd);
+ sqlite3MemoryBarrier(); /* compiler-defined memory barrier */
+ assert( fd->pMethods->xLock==nolockLock
+ || unixFileMutexNotheld((unixFile*)fd)
+ );
+ unixEnterMutex(); /* Also mutex, for redundancy */
+ unixLeaveMutex();
+}
+
+/*
+** Close a connection to shared-memory. Delete the underlying
+** storage if deleteFlag is true.
+**
+** If there is no shared memory associated with the connection then this
+** routine is a harmless no-op.
+*/
+static int unixShmUnmap(
+ sqlite3_file *fd, /* The underlying database file */
+ int deleteFlag /* Delete shared-memory if true */
+){
+ unixShm *p; /* The connection to be closed */
+ unixShmNode *pShmNode; /* The underlying shared-memory file */
+ unixShm **pp; /* For looping over sibling connections */
+ unixFile *pDbFd; /* The underlying database file */
+
+ pDbFd = (unixFile*)fd;
+ p = pDbFd->pShm;
+ if( p==0 ) return SQLITE_OK;
+ pShmNode = p->pShmNode;
+
+ assert( pShmNode==pDbFd->pInode->pShmNode );
+ assert( pShmNode->pInode==pDbFd->pInode );
+
+ /* Remove connection p from the set of connections associated
+ ** with pShmNode */
+ sqlite3_mutex_enter(pShmNode->mutex);
+ for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
+ *pp = p->pNext;
+
+ /* Free the connection p */
+ sqlite3_free(p);
+ pDbFd->pShm = 0;
+ sqlite3_mutex_leave(pShmNode->mutex);
+
+ /* If pShmNode->nRef has reached 0, then close the underlying
+ ** shared-memory file, too */
+ assert( unixFileMutexNotheld(pDbFd) );
+ unixEnterMutex();
+ assert( pShmNode->nRef>0 );
+ pShmNode->nRef--;
+ if( pShmNode->nRef==0 ){
+ if( deleteFlag && pShmNode->h>=0 ){
+ osUnlink(pShmNode->zFilename);
+ }
+ unixShmPurge(pDbFd);
+ }
+ unixLeaveMutex();
+
+ return SQLITE_OK;
+}
+
+
+#else
+# define unixShmMap 0
+# define unixShmLock 0
+# define unixShmBarrier 0
+# define unixShmUnmap 0
+#endif /* #ifndef SQLITE_OMIT_WAL */
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/*
+** If it is currently memory mapped, unmap file pFd.
+*/
+static void unixUnmapfile(unixFile *pFd){
+ assert( pFd->nFetchOut==0 );
+ if( pFd->pMapRegion ){
+ osMunmap(pFd->pMapRegion, pFd->mmapSizeActual);
+ pFd->pMapRegion = 0;
+ pFd->mmapSize = 0;
+ pFd->mmapSizeActual = 0;
+ }
+}
+
+/*
+** Attempt to set the size of the memory mapping maintained by file
+** descriptor pFd to nNew bytes. Any existing mapping is discarded.
+**
+** If successful, this function sets the following variables:
+**
+** unixFile.pMapRegion
+** unixFile.mmapSize
+** unixFile.mmapSizeActual
+**
+** If unsuccessful, an error message is logged via sqlite3_log() and
+** the three variables above are zeroed. In this case SQLite should
+** continue accessing the database using the xRead() and xWrite()
+** methods.
+*/
+static void unixRemapfile(
+ unixFile *pFd, /* File descriptor object */
+ i64 nNew /* Required mapping size */
+){
+ const char *zErr = "mmap";
+ int h = pFd->h; /* File descriptor open on db file */
+ u8 *pOrig = (u8 *)pFd->pMapRegion; /* Pointer to current file mapping */
+ i64 nOrig = pFd->mmapSizeActual; /* Size of pOrig region in bytes */
+ u8 *pNew = 0; /* Location of new mapping */
+ int flags = PROT_READ; /* Flags to pass to mmap() */
+
+ assert( pFd->nFetchOut==0 );
+ assert( nNew>pFd->mmapSize );
+ assert( nNew<=pFd->mmapSizeMax );
+ assert( nNew>0 );
+ assert( pFd->mmapSizeActual>=pFd->mmapSize );
+ assert( MAP_FAILED!=0 );
+
+#ifdef SQLITE_MMAP_READWRITE
+ if( (pFd->ctrlFlags & UNIXFILE_RDONLY)==0 ) flags |= PROT_WRITE;
+#endif
+
+ if( pOrig ){
+#if HAVE_MREMAP
+ i64 nReuse = pFd->mmapSize;
+#else
+ const int szSyspage = osGetpagesize();
+ i64 nReuse = (pFd->mmapSize & ~(szSyspage-1));
+#endif
+ u8 *pReq = &pOrig[nReuse];
+
+ /* Unmap any pages of the existing mapping that cannot be reused. */
+ if( nReuse!=nOrig ){
+ osMunmap(pReq, nOrig-nReuse);
+ }
+
+#if HAVE_MREMAP
+ pNew = osMremap(pOrig, nReuse, nNew, MREMAP_MAYMOVE);
+ zErr = "mremap";
+#else
+ pNew = osMmap(pReq, nNew-nReuse, flags, MAP_SHARED, h, nReuse);
+ if( pNew!=MAP_FAILED ){
+ if( pNew!=pReq ){
+ osMunmap(pNew, nNew - nReuse);
+ pNew = 0;
+ }else{
+ pNew = pOrig;
+ }
+ }
+#endif
+
+ /* The attempt to extend the existing mapping failed. Free it. */
+ if( pNew==MAP_FAILED || pNew==0 ){
+ osMunmap(pOrig, nReuse);
+ }
+ }
+
+ /* If pNew is still NULL, try to create an entirely new mapping. */
+ if( pNew==0 ){
+ pNew = osMmap(0, nNew, flags, MAP_SHARED, h, 0);
+ }
+
+ if( pNew==MAP_FAILED ){
+ pNew = 0;
+ nNew = 0;
+ unixLogError(SQLITE_OK, zErr, pFd->zPath);
+
+ /* If the mmap() above failed, assume that all subsequent mmap() calls
+ ** will probably fail too. Fall back to using xRead/xWrite exclusively
+ ** in this case. */
+ pFd->mmapSizeMax = 0;
+ }
+ pFd->pMapRegion = (void *)pNew;
+ pFd->mmapSize = pFd->mmapSizeActual = nNew;
+}
+
+/*
+** Memory map or remap the file opened by file-descriptor pFd (if the file
+** is already mapped, the existing mapping is replaced by the new). Or, if
+** there already exists a mapping for this file, and there are still
+** outstanding xFetch() references to it, this function is a no-op.
+**
+** If parameter nByte is non-negative, then it is the requested size of
+** the mapping to create. Otherwise, if nByte is less than zero, then the
+** requested size is the size of the file on disk. The actual size of the
+** created mapping is either the requested size or the value configured
+** using SQLITE_FCNTL_MMAP_LIMIT, whichever is smaller.
+**
+** SQLITE_OK is returned if no error occurs (even if the mapping is not
+** recreated as a result of outstanding references) or an SQLite error
+** code otherwise.
+*/
+static int unixMapfile(unixFile *pFd, i64 nMap){
+ assert( nMap>=0 || pFd->nFetchOut==0 );
+ assert( nMap>0 || (pFd->mmapSize==0 && pFd->pMapRegion==0) );
+ if( pFd->nFetchOut>0 ) return SQLITE_OK;
+
+ if( nMap<0 ){
+ struct stat statbuf; /* Low-level file information */
+ if( osFstat(pFd->h, &statbuf) ){
+ return SQLITE_IOERR_FSTAT;
+ }
+ nMap = statbuf.st_size;
+ }
+ if( nMap>pFd->mmapSizeMax ){
+ nMap = pFd->mmapSizeMax;
+ }
+
+ assert( nMap>0 || (pFd->mmapSize==0 && pFd->pMapRegion==0) );
+ if( nMap!=pFd->mmapSize ){
+ unixRemapfile(pFd, nMap);
+ }
+
+ return SQLITE_OK;
+}
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
+
+/*
+** If possible, return a pointer to a mapping of file fd starting at offset
+** iOff. The mapping must be valid for at least nAmt bytes.
+**
+** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
+** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
+** Finally, if an error does occur, return an SQLite error code. The final
+** value of *pp is undefined in this case.
+**
+** If this function does return a pointer, the caller must eventually
+** release the reference by calling unixUnfetch().
+*/
+static int unixFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
+#if SQLITE_MAX_MMAP_SIZE>0
+ unixFile *pFd = (unixFile *)fd; /* The underlying database file */
+#endif
+ *pp = 0;
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ if( pFd->mmapSizeMax>0 ){
+ if( pFd->pMapRegion==0 ){
+ int rc = unixMapfile(pFd, -1);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ if( pFd->mmapSize >= iOff+nAmt ){
+ *pp = &((u8 *)pFd->pMapRegion)[iOff];
+ pFd->nFetchOut++;
+ }
+ }
+#endif
+ return SQLITE_OK;
+}
+
+/*
+** If the third argument is non-NULL, then this function releases a
+** reference obtained by an earlier call to unixFetch(). The second
+** argument passed to this function must be the same as the corresponding
+** argument that was passed to the unixFetch() invocation.
+**
+** Or, if the third argument is NULL, then this function is being called
+** to inform the VFS layer that, according to POSIX, any existing mapping
+** may now be invalid and should be unmapped.
+*/
+static int unixUnfetch(sqlite3_file *fd, i64 iOff, void *p){
+#if SQLITE_MAX_MMAP_SIZE>0
+ unixFile *pFd = (unixFile *)fd; /* The underlying database file */
+ UNUSED_PARAMETER(iOff);
+
+ /* If p==0 (unmap the entire file) then there must be no outstanding
+ ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
+ ** then there must be at least one outstanding. */
+ assert( (p==0)==(pFd->nFetchOut==0) );
+
+ /* If p!=0, it must match the iOff value. */
+ assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
+
+ if( p ){
+ pFd->nFetchOut--;
+ }else{
+ unixUnmapfile(pFd);
+ }
+
+ assert( pFd->nFetchOut>=0 );
+#else
+ UNUSED_PARAMETER(fd);
+ UNUSED_PARAMETER(p);
+ UNUSED_PARAMETER(iOff);
+#endif
+ return SQLITE_OK;
+}
+
+/*
+** Here ends the implementation of all sqlite3_file methods.
+**
+********************** End sqlite3_file Methods *******************************
+******************************************************************************/
+
+/*
+** This division contains definitions of sqlite3_io_methods objects that
+** implement various file locking strategies. It also contains definitions
+** of "finder" functions. A finder-function is used to locate the appropriate
+** sqlite3_io_methods object for a particular database file. The pAppData
+** field of the sqlite3_vfs VFS objects are initialized to be pointers to
+** the correct finder-function for that VFS.
+**
+** Most finder functions return a pointer to a fixed sqlite3_io_methods
+** object. The only interesting finder-function is autolockIoFinder, which
+** looks at the filesystem type and tries to guess the best locking
+** strategy from that.
+**
+** For finder-function F, two objects are created:
+**
+** (1) The real finder-function named "FImpt()".
+**
+** (2) A constant pointer to this function named just "F".
+**
+**
+** A pointer to the F pointer is used as the pAppData value for VFS
+** objects. We have to do this instead of letting pAppData point
+** directly at the finder-function since C90 rules prevent a void*
+** from be cast into a function pointer.
+**
+**
+** Each instance of this macro generates two objects:
+**
+** * A constant sqlite3_io_methods object call METHOD that has locking
+** methods CLOSE, LOCK, UNLOCK, CKRESLOCK.
+**
+** * An I/O method finder function called FINDER that returns a pointer
+** to the METHOD object in the previous bullet.
+*/
+#define IOMETHODS(FINDER,METHOD,VERSION,CLOSE,LOCK,UNLOCK,CKLOCK,SHMMAP) \
+static const sqlite3_io_methods METHOD = { \
+ VERSION, /* iVersion */ \
+ CLOSE, /* xClose */ \
+ unixRead, /* xRead */ \
+ unixWrite, /* xWrite */ \
+ unixTruncate, /* xTruncate */ \
+ unixSync, /* xSync */ \
+ unixFileSize, /* xFileSize */ \
+ LOCK, /* xLock */ \
+ UNLOCK, /* xUnlock */ \
+ CKLOCK, /* xCheckReservedLock */ \
+ unixFileControl, /* xFileControl */ \
+ unixSectorSize, /* xSectorSize */ \
+ unixDeviceCharacteristics, /* xDeviceCapabilities */ \
+ SHMMAP, /* xShmMap */ \
+ unixShmLock, /* xShmLock */ \
+ unixShmBarrier, /* xShmBarrier */ \
+ unixShmUnmap, /* xShmUnmap */ \
+ unixFetch, /* xFetch */ \
+ unixUnfetch, /* xUnfetch */ \
+}; \
+static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){ \
+ UNUSED_PARAMETER(z); UNUSED_PARAMETER(p); \
+ return &METHOD; \
+} \
+static const sqlite3_io_methods *(*const FINDER)(const char*,unixFile *p) \
+ = FINDER##Impl;
+
+/*
+** Here are all of the sqlite3_io_methods objects for each of the
+** locking strategies. Functions that return pointers to these methods
+** are also created.
+*/
+IOMETHODS(
+ posixIoFinder, /* Finder function name */
+ posixIoMethods, /* sqlite3_io_methods object name */
+ 3, /* shared memory and mmap are enabled */
+ unixClose, /* xClose method */
+ unixLock, /* xLock method */
+ unixUnlock, /* xUnlock method */
+ unixCheckReservedLock, /* xCheckReservedLock method */
+ unixShmMap /* xShmMap method */
+)
+IOMETHODS(
+ nolockIoFinder, /* Finder function name */
+ nolockIoMethods, /* sqlite3_io_methods object name */
+ 3, /* shared memory and mmap are enabled */
+ nolockClose, /* xClose method */
+ nolockLock, /* xLock method */
+ nolockUnlock, /* xUnlock method */
+ nolockCheckReservedLock, /* xCheckReservedLock method */
+ 0 /* xShmMap method */
+)
+IOMETHODS(
+ dotlockIoFinder, /* Finder function name */
+ dotlockIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ dotlockClose, /* xClose method */
+ dotlockLock, /* xLock method */
+ dotlockUnlock, /* xUnlock method */
+ dotlockCheckReservedLock, /* xCheckReservedLock method */
+ 0 /* xShmMap method */
+)
+
+#if SQLITE_ENABLE_LOCKING_STYLE
+IOMETHODS(
+ flockIoFinder, /* Finder function name */
+ flockIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ flockClose, /* xClose method */
+ flockLock, /* xLock method */
+ flockUnlock, /* xUnlock method */
+ flockCheckReservedLock, /* xCheckReservedLock method */
+ 0 /* xShmMap method */
+)
+#endif
+
+#if OS_VXWORKS
+IOMETHODS(
+ semIoFinder, /* Finder function name */
+ semIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ semXClose, /* xClose method */
+ semXLock, /* xLock method */
+ semXUnlock, /* xUnlock method */
+ semXCheckReservedLock, /* xCheckReservedLock method */
+ 0 /* xShmMap method */
+)
+#endif
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+IOMETHODS(
+ afpIoFinder, /* Finder function name */
+ afpIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ afpClose, /* xClose method */
+ afpLock, /* xLock method */
+ afpUnlock, /* xUnlock method */
+ afpCheckReservedLock, /* xCheckReservedLock method */
+ 0 /* xShmMap method */
+)
+#endif
+
+/*
+** The proxy locking method is a "super-method" in the sense that it
+** opens secondary file descriptors for the conch and lock files and
+** it uses proxy, dot-file, AFP, and flock() locking methods on those
+** secondary files. For this reason, the division that implements
+** proxy locking is located much further down in the file. But we need
+** to go ahead and define the sqlite3_io_methods and finder function
+** for proxy locking here. So we forward declare the I/O methods.
+*/
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+static int proxyClose(sqlite3_file*);
+static int proxyLock(sqlite3_file*, int);
+static int proxyUnlock(sqlite3_file*, int);
+static int proxyCheckReservedLock(sqlite3_file*, int*);
+IOMETHODS(
+ proxyIoFinder, /* Finder function name */
+ proxyIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ proxyClose, /* xClose method */
+ proxyLock, /* xLock method */
+ proxyUnlock, /* xUnlock method */
+ proxyCheckReservedLock, /* xCheckReservedLock method */
+ 0 /* xShmMap method */
+)
+#endif
+
+/* nfs lockd on OSX 10.3+ doesn't clear write locks when a read lock is set */
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+IOMETHODS(
+ nfsIoFinder, /* Finder function name */
+ nfsIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ unixClose, /* xClose method */
+ unixLock, /* xLock method */
+ nfsUnlock, /* xUnlock method */
+ unixCheckReservedLock, /* xCheckReservedLock method */
+ 0 /* xShmMap method */
+)
+#endif
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+/*
+** This "finder" function attempts to determine the best locking strategy
+** for the database file "filePath". It then returns the sqlite3_io_methods
+** object that implements that strategy.
+**
+** This is for MacOSX only.
+*/
+static const sqlite3_io_methods *autolockIoFinderImpl(
+ const char *filePath, /* name of the database file */
+ unixFile *pNew /* open file object for the database file */
+){
+ static const struct Mapping {
+ const char *zFilesystem; /* Filesystem type name */
+ const sqlite3_io_methods *pMethods; /* Appropriate locking method */
+ } aMap[] = {
+ { "hfs", &posixIoMethods },
+ { "ufs", &posixIoMethods },
+ { "afpfs", &afpIoMethods },
+ { "smbfs", &afpIoMethods },
+ { "webdav", &nolockIoMethods },
+ { 0, 0 }
+ };
+ int i;
+ struct statfs fsInfo;
+ struct flock lockInfo;
+
+ if( !filePath ){
+ /* If filePath==NULL that means we are dealing with a transient file
+ ** that does not need to be locked. */
+ return &nolockIoMethods;
+ }
+ if( statfs(filePath, &fsInfo) != -1 ){
+ if( fsInfo.f_flags & MNT_RDONLY ){
+ return &nolockIoMethods;
+ }
+ for(i=0; aMap[i].zFilesystem; i++){
+ if( strcmp(fsInfo.f_fstypename, aMap[i].zFilesystem)==0 ){
+ return aMap[i].pMethods;
+ }
+ }
+ }
+
+ /* Default case. Handles, amongst others, "nfs".
+ ** Test byte-range lock using fcntl(). If the call succeeds,
+ ** assume that the file-system supports POSIX style locks.
+ */
+ lockInfo.l_len = 1;
+ lockInfo.l_start = 0;
+ lockInfo.l_whence = SEEK_SET;
+ lockInfo.l_type = F_RDLCK;
+ if( osFcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
+ if( strcmp(fsInfo.f_fstypename, "nfs")==0 ){
+ return &nfsIoMethods;
+ } else {
+ return &posixIoMethods;
+ }
+ }else{
+ return &dotlockIoMethods;
+ }
+}
+static const sqlite3_io_methods
+ *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+
+#if OS_VXWORKS
+/*
+** This "finder" function for VxWorks checks to see if posix advisory
+** locking works. If it does, then that is what is used. If it does not
+** work, then fallback to named semaphore locking.
+*/
+static const sqlite3_io_methods *vxworksIoFinderImpl(
+ const char *filePath, /* name of the database file */
+ unixFile *pNew /* the open file object */
+){
+ struct flock lockInfo;
+
+ if( !filePath ){
+ /* If filePath==NULL that means we are dealing with a transient file
+ ** that does not need to be locked. */
+ return &nolockIoMethods;
+ }
+
+ /* Test if fcntl() is supported and use POSIX style locks.
+ ** Otherwise fall back to the named semaphore method.
+ */
+ lockInfo.l_len = 1;
+ lockInfo.l_start = 0;
+ lockInfo.l_whence = SEEK_SET;
+ lockInfo.l_type = F_RDLCK;
+ if( osFcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
+ return &posixIoMethods;
+ }else{
+ return &semIoMethods;
+ }
+}
+static const sqlite3_io_methods
+ *(*const vxworksIoFinder)(const char*,unixFile*) = vxworksIoFinderImpl;
+
+#endif /* OS_VXWORKS */
+
+/*
+** An abstract type for a pointer to an IO method finder function:
+*/
+typedef const sqlite3_io_methods *(*finder_type)(const char*,unixFile*);
+
+
+/****************************************************************************
+**************************** sqlite3_vfs methods ****************************
+**
+** This division contains the implementation of methods on the
+** sqlite3_vfs object.
+*/
+
+/*
+** Initialize the contents of the unixFile structure pointed to by pId.
+*/
+static int fillInUnixFile(
+ sqlite3_vfs *pVfs, /* Pointer to vfs object */
+ int h, /* Open file descriptor of file being opened */
+ sqlite3_file *pId, /* Write to the unixFile structure here */
+ const char *zFilename, /* Name of the file being opened */
+ int ctrlFlags /* Zero or more UNIXFILE_* values */
+){
+ const sqlite3_io_methods *pLockingStyle;
+ unixFile *pNew = (unixFile *)pId;
+ int rc = SQLITE_OK;
+
+ assert( pNew->pInode==NULL );
+
+ /* No locking occurs in temporary files */
+ assert( zFilename!=0 || (ctrlFlags & UNIXFILE_NOLOCK)!=0 );
+
+ OSTRACE(("OPEN %-3d %s\n", h, zFilename));
+ pNew->h = h;
+ pNew->pVfs = pVfs;
+ pNew->zPath = zFilename;
+ pNew->ctrlFlags = (u8)ctrlFlags;
+#if SQLITE_MAX_MMAP_SIZE>0
+ pNew->mmapSizeMax = sqlite3GlobalConfig.szMmap;
+#endif
+ if( sqlite3_uri_boolean(((ctrlFlags & UNIXFILE_URI) ? zFilename : 0),
+ "psow", SQLITE_POWERSAFE_OVERWRITE) ){
+ pNew->ctrlFlags |= UNIXFILE_PSOW;
+ }
+ if( strcmp(pVfs->zName,"unix-excl")==0 ){
+ pNew->ctrlFlags |= UNIXFILE_EXCL;
+ }
+
+#if OS_VXWORKS
+ pNew->pId = vxworksFindFileId(zFilename);
+ if( pNew->pId==0 ){
+ ctrlFlags |= UNIXFILE_NOLOCK;
+ rc = SQLITE_NOMEM_BKPT;
+ }
+#endif
+
+ if( ctrlFlags & UNIXFILE_NOLOCK ){
+ pLockingStyle = &nolockIoMethods;
+ }else{
+ pLockingStyle = (**(finder_type*)pVfs->pAppData)(zFilename, pNew);
+#if SQLITE_ENABLE_LOCKING_STYLE
+ /* Cache zFilename in the locking context (AFP and dotlock override) for
+ ** proxyLock activation is possible (remote proxy is based on db name)
+ ** zFilename remains valid until file is closed, to support */
+ pNew->lockingContext = (void*)zFilename;
+#endif
+ }
+
+ if( pLockingStyle == &posixIoMethods
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+ || pLockingStyle == &nfsIoMethods
+#endif
+ ){
+ unixEnterMutex();
+ rc = findInodeInfo(pNew, &pNew->pInode);
+ if( rc!=SQLITE_OK ){
+ /* If an error occurred in findInodeInfo(), close the file descriptor
+ ** immediately, before releasing the mutex. findInodeInfo() may fail
+ ** in two scenarios:
+ **
+ ** (a) A call to fstat() failed.
+ ** (b) A malloc failed.
+ **
+ ** Scenario (b) may only occur if the process is holding no other
+ ** file descriptors open on the same file. If there were other file
+ ** descriptors on this file, then no malloc would be required by
+ ** findInodeInfo(). If this is the case, it is quite safe to close
+ ** handle h - as it is guaranteed that no posix locks will be released
+ ** by doing so.
+ **
+ ** If scenario (a) caused the error then things are not so safe. The
+ ** implicit assumption here is that if fstat() fails, things are in
+ ** such bad shape that dropping a lock or two doesn't matter much.
+ */
+ robust_close(pNew, h, __LINE__);
+ h = -1;
+ }
+ unixLeaveMutex();
+ }
+
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+ else if( pLockingStyle == &afpIoMethods ){
+ /* AFP locking uses the file path so it needs to be included in
+ ** the afpLockingContext.
+ */
+ afpLockingContext *pCtx;
+ pNew->lockingContext = pCtx = sqlite3_malloc64( sizeof(*pCtx) );
+ if( pCtx==0 ){
+ rc = SQLITE_NOMEM_BKPT;
+ }else{
+ /* NB: zFilename exists and remains valid until the file is closed
+ ** according to requirement F11141. So we do not need to make a
+ ** copy of the filename. */
+ pCtx->dbPath = zFilename;
+ pCtx->reserved = 0;
+ srandomdev();
+ unixEnterMutex();
+ rc = findInodeInfo(pNew, &pNew->pInode);
+ if( rc!=SQLITE_OK ){
+ sqlite3_free(pNew->lockingContext);
+ robust_close(pNew, h, __LINE__);
+ h = -1;
+ }
+ unixLeaveMutex();
+ }
+ }
+#endif
+
+ else if( pLockingStyle == &dotlockIoMethods ){
+ /* Dotfile locking uses the file path so it needs to be included in
+ ** the dotlockLockingContext
+ */
+ char *zLockFile;
+ int nFilename;
+ assert( zFilename!=0 );
+ nFilename = (int)strlen(zFilename) + 6;
+ zLockFile = (char *)sqlite3_malloc64(nFilename);
+ if( zLockFile==0 ){
+ rc = SQLITE_NOMEM_BKPT;
+ }else{
+ sqlite3_snprintf(nFilename, zLockFile, "%s" DOTLOCK_SUFFIX, zFilename);
+ }
+ pNew->lockingContext = zLockFile;
+ }
+
+#if OS_VXWORKS
+ else if( pLockingStyle == &semIoMethods ){
+ /* Named semaphore locking uses the file path so it needs to be
+ ** included in the semLockingContext
+ */
+ unixEnterMutex();
+ rc = findInodeInfo(pNew, &pNew->pInode);
+ if( (rc==SQLITE_OK) && (pNew->pInode->pSem==NULL) ){
+ char *zSemName = pNew->pInode->aSemName;
+ int n;
+ sqlite3_snprintf(MAX_PATHNAME, zSemName, "/%s.sem",
+ pNew->pId->zCanonicalName);
+ for( n=1; zSemName[n]; n++ )
+ if( zSemName[n]=='/' ) zSemName[n] = '_';
+ pNew->pInode->pSem = sem_open(zSemName, O_CREAT, 0666, 1);
+ if( pNew->pInode->pSem == SEM_FAILED ){
+ rc = SQLITE_NOMEM_BKPT;
+ pNew->pInode->aSemName[0] = '\0';
+ }
+ }
+ unixLeaveMutex();
+ }
+#endif
+
+ storeLastErrno(pNew, 0);
+#if OS_VXWORKS
+ if( rc!=SQLITE_OK ){
+ if( h>=0 ) robust_close(pNew, h, __LINE__);
+ h = -1;
+ osUnlink(zFilename);
+ pNew->ctrlFlags |= UNIXFILE_DELETE;
+ }
+#endif
+ if( rc!=SQLITE_OK ){
+ if( h>=0 ) robust_close(pNew, h, __LINE__);
+ }else{
+ pNew->pMethod = pLockingStyle;
+ OpenCounter(+1);
+ verifyDbFile(pNew);
+ }
+ return rc;
+}
+
+/*
+** Return the name of a directory in which to put temporary files.
+** If no suitable temporary file directory can be found, return NULL.
+*/
+static const char *unixTempFileDir(void){
+ static const char *azDirs[] = {
+ 0,
+ 0,
+ "/var/tmp",
+ "/usr/tmp",
+ "/tmp",
+ "."
+ };
+ unsigned int i = 0;
+ struct stat buf;
+ const char *zDir = sqlite3_temp_directory;
+
+ if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
+ if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");
+ while(1){
+ if( zDir!=0
+ && osStat(zDir, &buf)==0
+ && S_ISDIR(buf.st_mode)
+ && osAccess(zDir, 03)==0
+ ){
+ return zDir;
+ }
+ if( i>=sizeof(azDirs)/sizeof(azDirs[0]) ) break;
+ zDir = azDirs[i++];
+ }
+ return 0;
+}
+
+/*
+** Create a temporary file name in zBuf. zBuf must be allocated
+** by the calling process and must be big enough to hold at least
+** pVfs->mxPathname bytes.
+*/
+static int unixGetTempname(int nBuf, char *zBuf){
+ const char *zDir;
+ int iLimit = 0;
+
+ /* It's odd to simulate an io-error here, but really this is just
+ ** using the io-error infrastructure to test that SQLite handles this
+ ** function failing.
+ */
+ zBuf[0] = 0;
+ SimulateIOError( return SQLITE_IOERR );
+
+ zDir = unixTempFileDir();
+ if( zDir==0 ) return SQLITE_IOERR_GETTEMPPATH;
+ do{
+ u64 r;
+ sqlite3_randomness(sizeof(r), &r);
+ assert( nBuf>2 );
+ zBuf[nBuf-2] = 0;
+ sqlite3_snprintf(nBuf, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX"%llx%c",
+ zDir, r, 0);
+ if( zBuf[nBuf-2]!=0 || (iLimit++)>10 ) return SQLITE_ERROR;
+ }while( osAccess(zBuf,0)==0 );
+ return SQLITE_OK;
+}
+
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+/*
+** Routine to transform a unixFile into a proxy-locking unixFile.
+** Implementation in the proxy-lock division, but used by unixOpen()
+** if SQLITE_PREFER_PROXY_LOCKING is defined.
+*/
+static int proxyTransformUnixFile(unixFile*, const char*);
+#endif
+
+/*
+** Search for an unused file descriptor that was opened on the database
+** file (not a journal or master-journal file) identified by pathname
+** zPath with SQLITE_OPEN_XXX flags matching those passed as the second
+** argument to this function.
+**
+** Such a file descriptor may exist if a database connection was closed
+** but the associated file descriptor could not be closed because some
+** other file descriptor open on the same file is holding a file-lock.
+** Refer to comments in the unixClose() function and the lengthy comment
+** describing "Posix Advisory Locking" at the start of this file for
+** further details. Also, ticket #4018.
+**
+** If a suitable file descriptor is found, then it is returned. If no
+** such file descriptor is located, -1 is returned.
+*/
+static UnixUnusedFd *findReusableFd(const char *zPath, int flags){
+ UnixUnusedFd *pUnused = 0;
+
+ /* Do not search for an unused file descriptor on vxworks. Not because
+ ** vxworks would not benefit from the change (it might, we're not sure),
+ ** but because no way to test it is currently available. It is better
+ ** not to risk breaking vxworks support for the sake of such an obscure
+ ** feature. */
+#if !OS_VXWORKS
+ struct stat sStat; /* Results of stat() call */
+
+ unixEnterMutex();
+
+ /* A stat() call may fail for various reasons. If this happens, it is
+ ** almost certain that an open() call on the same path will also fail.
+ ** For this reason, if an error occurs in the stat() call here, it is
+ ** ignored and -1 is returned. The caller will try to open a new file
+ ** descriptor on the same path, fail, and return an error to SQLite.
+ **
+ ** Even if a subsequent open() call does succeed, the consequences of
+ ** not searching for a reusable file descriptor are not dire. */
+ if( inodeList!=0 && 0==osStat(zPath, &sStat) ){
+ unixInodeInfo *pInode;
+
+ pInode = inodeList;
+ while( pInode && (pInode->fileId.dev!=sStat.st_dev
+ || pInode->fileId.ino!=(u64)sStat.st_ino) ){
+ pInode = pInode->pNext;
+ }
+ if( pInode ){
+ UnixUnusedFd **pp;
+ assert( sqlite3_mutex_notheld(pInode->pLockMutex) );
+ sqlite3_mutex_enter(pInode->pLockMutex);
+ for(pp=&pInode->pUnused; *pp && (*pp)->flags!=flags; pp=&((*pp)->pNext));
+ pUnused = *pp;
+ if( pUnused ){
+ *pp = pUnused->pNext;
+ }
+ sqlite3_mutex_leave(pInode->pLockMutex);
+ }
+ }
+ unixLeaveMutex();
+#endif /* if !OS_VXWORKS */
+ return pUnused;
+}
+
+/*
+** Find the mode, uid and gid of file zFile.
+*/
+static int getFileMode(
+ const char *zFile, /* File name */
+ mode_t *pMode, /* OUT: Permissions of zFile */
+ uid_t *pUid, /* OUT: uid of zFile. */
+ gid_t *pGid /* OUT: gid of zFile. */
+){
+ struct stat sStat; /* Output of stat() on database file */
+ int rc = SQLITE_OK;
+ if( 0==osStat(zFile, &sStat) ){
+ *pMode = sStat.st_mode & 0777;
+ *pUid = sStat.st_uid;
+ *pGid = sStat.st_gid;
+ }else{
+ rc = SQLITE_IOERR_FSTAT;
+ }
+ return rc;
+}
+
+/*
+** This function is called by unixOpen() to determine the unix permissions
+** to create new files with. If no error occurs, then SQLITE_OK is returned
+** and a value suitable for passing as the third argument to open(2) is
+** written to *pMode. If an IO error occurs, an SQLite error code is
+** returned and the value of *pMode is not modified.
+**
+** In most cases, this routine sets *pMode to 0, which will become
+** an indication to robust_open() to create the file using
+** SQLITE_DEFAULT_FILE_PERMISSIONS adjusted by the umask.
+** But if the file being opened is a WAL or regular journal file, then
+** this function queries the file-system for the permissions on the
+** corresponding database file and sets *pMode to this value. Whenever
+** possible, WAL and journal files are created using the same permissions
+** as the associated database file.
+**
+** If the SQLITE_ENABLE_8_3_NAMES option is enabled, then the
+** original filename is unavailable. But 8_3_NAMES is only used for
+** FAT filesystems and permissions do not matter there, so just use
+** the default permissions.
+*/
+static int findCreateFileMode(
+ const char *zPath, /* Path of file (possibly) being created */
+ int flags, /* Flags passed as 4th argument to xOpen() */
+ mode_t *pMode, /* OUT: Permissions to open file with */
+ uid_t *pUid, /* OUT: uid to set on the file */
+ gid_t *pGid /* OUT: gid to set on the file */
+){
+ int rc = SQLITE_OK; /* Return Code */
+ *pMode = 0;
+ *pUid = 0;
+ *pGid = 0;
+ if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
+ char zDb[MAX_PATHNAME+1]; /* Database file path */
+ int nDb; /* Number of valid bytes in zDb */
+
+ /* zPath is a path to a WAL or journal file. The following block derives
+ ** the path to the associated database file from zPath. This block handles
+ ** the following naming conventions:
+ **
+ ** "-journal"
+ ** "-wal"
+ ** "-journalNN"
+ ** "-walNN"
+ **
+ ** where NN is a decimal number. The NN naming schemes are
+ ** used by the test_multiplex.c module.
+ */
+ nDb = sqlite3Strlen30(zPath) - 1;
+ while( zPath[nDb]!='-' ){
+ /* In normal operation, the journal file name will always contain
+ ** a '-' character. However in 8+3 filename mode, or if a corrupt
+ ** rollback journal specifies a master journal with a goofy name, then
+ ** the '-' might be missing. */
+ if( nDb==0 || zPath[nDb]=='.' ) return SQLITE_OK;
+ nDb--;
+ }
+ memcpy(zDb, zPath, nDb);
+ zDb[nDb] = '\0';
+
+ rc = getFileMode(zDb, pMode, pUid, pGid);
+ }else if( flags & SQLITE_OPEN_DELETEONCLOSE ){
+ *pMode = 0600;
+ }else if( flags & SQLITE_OPEN_URI ){
+ /* If this is a main database file and the file was opened using a URI
+ ** filename, check for the "modeof" parameter. If present, interpret
+ ** its value as a filename and try to copy the mode, uid and gid from
+ ** that file. */
+ const char *z = sqlite3_uri_parameter(zPath, "modeof");
+ if( z ){
+ rc = getFileMode(z, pMode, pUid, pGid);
+ }
+ }
+ return rc;
+}
+
+/*
+** Open the file zPath.
+**
+** Previously, the SQLite OS layer used three functions in place of this
+** one:
+**
+** sqlite3OsOpenReadWrite();
+** sqlite3OsOpenReadOnly();
+** sqlite3OsOpenExclusive();
+**
+** These calls correspond to the following combinations of flags:
+**
+** ReadWrite() -> (READWRITE | CREATE)
+** ReadOnly() -> (READONLY)
+** OpenExclusive() -> (READWRITE | CREATE | EXCLUSIVE)
+**
+** The old OpenExclusive() accepted a boolean argument - "delFlag". If
+** true, the file was configured to be automatically deleted when the
+** file handle closed. To achieve the same effect using this new
+** interface, add the DELETEONCLOSE flag to those specified above for
+** OpenExclusive().
+*/
+static int unixOpen(
+ sqlite3_vfs *pVfs, /* The VFS for which this is the xOpen method */
+ const char *zPath, /* Pathname of file to be opened */
+ sqlite3_file *pFile, /* The file descriptor to be filled in */
+ int flags, /* Input flags to control the opening */
+ int *pOutFlags /* Output flags returned to SQLite core */
+){
+ unixFile *p = (unixFile *)pFile;
+ int fd = -1; /* File descriptor returned by open() */
+ int openFlags = 0; /* Flags to pass to open() */
+ int eType = flags&0xFFFFFF00; /* Type of file to open */
+ int noLock; /* True to omit locking primitives */
+ int rc = SQLITE_OK; /* Function Return Code */
+ int ctrlFlags = 0; /* UNIXFILE_* flags */
+
+ int isExclusive = (flags & SQLITE_OPEN_EXCLUSIVE);
+ int isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE);
+ int isCreate = (flags & SQLITE_OPEN_CREATE);
+ int isReadonly = (flags & SQLITE_OPEN_READONLY);
+ int isReadWrite = (flags & SQLITE_OPEN_READWRITE);
+#if SQLITE_ENABLE_LOCKING_STYLE
+ int isAutoProxy = (flags & SQLITE_OPEN_AUTOPROXY);
+#endif
+#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE
+ struct statfs fsInfo;
+#endif
+
+ /* If creating a master or main-file journal, this function will open
+ ** a file-descriptor on the directory too. The first time unixSync()
+ ** is called the directory file descriptor will be fsync()ed and close()d.
+ */
+ int isNewJrnl = (isCreate && (
+ eType==SQLITE_OPEN_MASTER_JOURNAL
+ || eType==SQLITE_OPEN_MAIN_JOURNAL
+ || eType==SQLITE_OPEN_WAL
+ ));
+
+ /* If argument zPath is a NULL pointer, this function is required to open
+ ** a temporary file. Use this buffer to store the file name in.
+ */
+ char zTmpname[MAX_PATHNAME+2];
+ const char *zName = zPath;
+
+ /* Check the following statements are true:
+ **
+ ** (a) Exactly one of the READWRITE and READONLY flags must be set, and
+ ** (b) if CREATE is set, then READWRITE must also be set, and
+ ** (c) if EXCLUSIVE is set, then CREATE must also be set.
+ ** (d) if DELETEONCLOSE is set, then CREATE must also be set.
+ */
+ assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
+ assert(isCreate==0 || isReadWrite);
+ assert(isExclusive==0 || isCreate);
+ assert(isDelete==0 || isCreate);
+
+ /* The main DB, main journal, WAL file and master journal are never
+ ** automatically deleted. Nor are they ever temporary files. */
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
+
+ /* Assert that the upper layer has set one of the "file-type" flags. */
+ assert( eType==SQLITE_OPEN_MAIN_DB || eType==SQLITE_OPEN_TEMP_DB
+ || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL
+ || eType==SQLITE_OPEN_SUBJOURNAL || eType==SQLITE_OPEN_MASTER_JOURNAL
+ || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
+ );
+
+ /* Detect a pid change and reset the PRNG. There is a race condition
+ ** here such that two or more threads all trying to open databases at
+ ** the same instant might all reset the PRNG. But multiple resets
+ ** are harmless.
+ */
+ if( randomnessPid!=osGetpid(0) ){
+ randomnessPid = osGetpid(0);
+ sqlite3_randomness(0,0);
+ }
+ memset(p, 0, sizeof(unixFile));
+
+ if( eType==SQLITE_OPEN_MAIN_DB ){
+ UnixUnusedFd *pUnused;
+ pUnused = findReusableFd(zName, flags);
+ if( pUnused ){
+ fd = pUnused->fd;
+ }else{
+ pUnused = sqlite3_malloc64(sizeof(*pUnused));
+ if( !pUnused ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ }
+ p->pPreallocatedUnused = pUnused;
+
+ /* Database filenames are double-zero terminated if they are not
+ ** URIs with parameters. Hence, they can always be passed into
+ ** sqlite3_uri_parameter(). */
+ assert( (flags & SQLITE_OPEN_URI) || zName[strlen(zName)+1]==0 );
+
+ }else if( !zName ){
+ /* If zName is NULL, the upper layer is requesting a temp file. */
+ assert(isDelete && !isNewJrnl);
+ rc = unixGetTempname(pVfs->mxPathname, zTmpname);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ zName = zTmpname;
+
+ /* Generated temporary filenames are always double-zero terminated
+ ** for use by sqlite3_uri_parameter(). */
+ assert( zName[strlen(zName)+1]==0 );
+ }
+
+ /* Determine the value of the flags parameter passed to POSIX function
+ ** open(). These must be calculated even if open() is not called, as
+ ** they may be stored as part of the file handle and used by the
+ ** 'conch file' locking functions later on. */
+ if( isReadonly ) openFlags |= O_RDONLY;
+ if( isReadWrite ) openFlags |= O_RDWR;
+ if( isCreate ) openFlags |= O_CREAT;
+ if( isExclusive ) openFlags |= (O_EXCL|O_NOFOLLOW);
+ openFlags |= (O_LARGEFILE|O_BINARY);
+
+ if( fd<0 ){
+ mode_t openMode; /* Permissions to create file with */
+ uid_t uid; /* Userid for the file */
+ gid_t gid; /* Groupid for the file */
+ rc = findCreateFileMode(zName, flags, &openMode, &uid, &gid);
+ if( rc!=SQLITE_OK ){
+ assert( !p->pPreallocatedUnused );
+ assert( eType==SQLITE_OPEN_WAL || eType==SQLITE_OPEN_MAIN_JOURNAL );
+ return rc;
+ }
+ fd = robust_open(zName, openFlags, openMode);
+ OSTRACE(("OPENX %-3d %s 0%o\n", fd, zName, openFlags));
+ assert( !isExclusive || (openFlags & O_CREAT)!=0 );
+ if( fd<0 ){
+ if( isNewJrnl && errno==EACCES && osAccess(zName, F_OK) ){
+ /* If unable to create a journal because the directory is not
+ ** writable, change the error code to indicate that. */
+ rc = SQLITE_READONLY_DIRECTORY;
+ }else if( errno!=EISDIR && isReadWrite ){
+ /* Failed to open the file for read/write access. Try read-only. */
+ flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
+ openFlags &= ~(O_RDWR|O_CREAT);
+ flags |= SQLITE_OPEN_READONLY;
+ openFlags |= O_RDONLY;
+ isReadonly = 1;
+ fd = robust_open(zName, openFlags, openMode);
+ }
+ }
+ if( fd<0 ){
+ int rc2 = unixLogError(SQLITE_CANTOPEN_BKPT, "open", zName);
+ if( rc==SQLITE_OK ) rc = rc2;
+ goto open_finished;
+ }
+
+ /* If this process is running as root and if creating a new rollback
+ ** journal or WAL file, set the ownership of the journal or WAL to be
+ ** the same as the original database.
+ */
+ if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
+ robustFchown(fd, uid, gid);
+ }
+ }
+ assert( fd>=0 );
+ if( pOutFlags ){
+ *pOutFlags = flags;
+ }
+
+ if( p->pPreallocatedUnused ){
+ p->pPreallocatedUnused->fd = fd;
+ p->pPreallocatedUnused->flags = flags;
+ }
+
+ if( isDelete ){
+#if OS_VXWORKS
+ zPath = zName;
+#elif defined(SQLITE_UNLINK_AFTER_CLOSE)
+ zPath = sqlite3_mprintf("%s", zName);
+ if( zPath==0 ){
+ robust_close(p, fd, __LINE__);
+ return SQLITE_NOMEM_BKPT;
+ }
+#else
+ osUnlink(zName);
+#endif
+ }
+#if SQLITE_ENABLE_LOCKING_STYLE
+ else{
+ p->openFlags = openFlags;
+ }
+#endif
+
+#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE
+ if( fstatfs(fd, &fsInfo) == -1 ){
+ storeLastErrno(p, errno);
+ robust_close(p, fd, __LINE__);
+ return SQLITE_IOERR_ACCESS;
+ }
+ if (0 == strncmp("msdos", fsInfo.f_fstypename, 5)) {
+ ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_MSDOS;
+ }
+ if (0 == strncmp("exfat", fsInfo.f_fstypename, 5)) {
+ ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_MSDOS;
+ }
+#endif
+
+ /* Set up appropriate ctrlFlags */
+ if( isDelete ) ctrlFlags |= UNIXFILE_DELETE;
+ if( isReadonly ) ctrlFlags |= UNIXFILE_RDONLY;
+ noLock = eType!=SQLITE_OPEN_MAIN_DB;
+ if( noLock ) ctrlFlags |= UNIXFILE_NOLOCK;
+ if( isNewJrnl ) ctrlFlags |= UNIXFILE_DIRSYNC;
+ if( flags & SQLITE_OPEN_URI ) ctrlFlags |= UNIXFILE_URI;
+
+#if SQLITE_ENABLE_LOCKING_STYLE
+#if SQLITE_PREFER_PROXY_LOCKING
+ isAutoProxy = 1;
+#endif
+ if( isAutoProxy && (zPath!=NULL) && (!noLock) && pVfs->xOpen ){
+ char *envforce = getenv("SQLITE_FORCE_PROXY_LOCKING");
+ int useProxy = 0;
+
+ /* SQLITE_FORCE_PROXY_LOCKING==1 means force always use proxy, 0 means
+ ** never use proxy, NULL means use proxy for non-local files only. */
+ if( envforce!=NULL ){
+ useProxy = atoi(envforce)>0;
+ }else{
+ useProxy = !(fsInfo.f_flags&MNT_LOCAL);
+ }
+ if( useProxy ){
+ rc = fillInUnixFile(pVfs, fd, pFile, zPath, ctrlFlags);
+ if( rc==SQLITE_OK ){
+ rc = proxyTransformUnixFile((unixFile*)pFile, ":auto:");
+ if( rc!=SQLITE_OK ){
+ /* Use unixClose to clean up the resources added in fillInUnixFile
+ ** and clear all the structure's references. Specifically,
+ ** pFile->pMethods will be NULL so sqlite3OsClose will be a no-op
+ */
+ unixClose(pFile);
+ return rc;
+ }
+ }
+ goto open_finished;
+ }
+ }
+#endif
+
+ assert( zPath==0 || zPath[0]=='/'
+ || eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL
+ );
+ rc = fillInUnixFile(pVfs, fd, pFile, zPath, ctrlFlags);
+
+open_finished:
+ if( rc!=SQLITE_OK ){
+ sqlite3_free(p->pPreallocatedUnused);
+ }
+ return rc;
+}
+
+
+/*
+** Delete the file at zPath. If the dirSync argument is true, fsync()
+** the directory after deleting the file.
+*/
+static int unixDelete(
+ sqlite3_vfs *NotUsed, /* VFS containing this as the xDelete method */
+ const char *zPath, /* Name of file to be deleted */
+ int dirSync /* If true, fsync() directory after deleting file */
+){
+ int rc = SQLITE_OK;
+ UNUSED_PARAMETER(NotUsed);
+ SimulateIOError(return SQLITE_IOERR_DELETE);
+ if( osUnlink(zPath)==(-1) ){
+ if( errno==ENOENT
+#if OS_VXWORKS
+ || osAccess(zPath,0)!=0
+#endif
+ ){
+ rc = SQLITE_IOERR_DELETE_NOENT;
+ }else{
+ rc = unixLogError(SQLITE_IOERR_DELETE, "unlink", zPath);
+ }
+ return rc;
+ }
+#ifndef SQLITE_DISABLE_DIRSYNC
+ if( (dirSync & 1)!=0 ){
+ int fd;
+ rc = osOpenDirectory(zPath, &fd);
+ if( rc==SQLITE_OK ){
+ if( full_fsync(fd,0,0) ){
+ rc = unixLogError(SQLITE_IOERR_DIR_FSYNC, "fsync", zPath);
+ }
+ robust_close(0, fd, __LINE__);
+ }else{
+ assert( rc==SQLITE_CANTOPEN );
+ rc = SQLITE_OK;
+ }
+ }
+#endif
+ return rc;
+}
+
+/*
+** Test the existence of or access permissions of file zPath. The
+** test performed depends on the value of flags:
+**
+** SQLITE_ACCESS_EXISTS: Return 1 if the file exists
+** SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
+** SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
+**
+** Otherwise return 0.
+*/
+static int unixAccess(
+ sqlite3_vfs *NotUsed, /* The VFS containing this xAccess method */
+ const char *zPath, /* Path of the file to examine */
+ int flags, /* What do we want to learn about the zPath file? */
+ int *pResOut /* Write result boolean here */
+){
+ UNUSED_PARAMETER(NotUsed);
+ SimulateIOError( return SQLITE_IOERR_ACCESS; );
+ assert( pResOut!=0 );
+
+ /* The spec says there are three possible values for flags. But only
+ ** two of them are actually used */
+ assert( flags==SQLITE_ACCESS_EXISTS || flags==SQLITE_ACCESS_READWRITE );
+
+ if( flags==SQLITE_ACCESS_EXISTS ){
+ struct stat buf;
+ *pResOut = (0==osStat(zPath, &buf) && buf.st_size>0);
+ }else{
+ *pResOut = osAccess(zPath, W_OK|R_OK)==0;
+ }
+ return SQLITE_OK;
+}
+
+/*
+**
+*/
+static int mkFullPathname(
+ const char *zPath, /* Input path */
+ char *zOut, /* Output buffer */
+ int nOut /* Allocated size of buffer zOut */
+){
+ int nPath = sqlite3Strlen30(zPath);
+ int iOff = 0;
+ if( zPath[0]!='/' ){
+ if( osGetcwd(zOut, nOut-2)==0 ){
+ return unixLogError(SQLITE_CANTOPEN_BKPT, "getcwd", zPath);
+ }
+ iOff = sqlite3Strlen30(zOut);
+ zOut[iOff++] = '/';
+ }
+ if( (iOff+nPath+1)>nOut ){
+ /* SQLite assumes that xFullPathname() nul-terminates the output buffer
+ ** even if it returns an error. */
+ zOut[iOff] = '\0';
+ return SQLITE_CANTOPEN_BKPT;
+ }
+ sqlite3_snprintf(nOut-iOff, &zOut[iOff], "%s", zPath);
+ return SQLITE_OK;
+}
+
+/*
+** Turn a relative pathname into a full pathname. The relative path
+** is stored as a nul-terminated string in the buffer pointed to by
+** zPath.
+**
+** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes
+** (in this case, MAX_PATHNAME bytes). The full-path is written to
+** this buffer before returning.
+*/
+static int unixFullPathname(
+ sqlite3_vfs *pVfs, /* Pointer to vfs object */
+ const char *zPath, /* Possibly relative input path */
+ int nOut, /* Size of output buffer in bytes */
+ char *zOut /* Output buffer */
+){
+#if !defined(HAVE_READLINK) || !defined(HAVE_LSTAT)
+ return mkFullPathname(zPath, zOut, nOut);
+#else
+ int rc = SQLITE_OK;
+ int nByte;
+ int nLink = 1; /* Number of symbolic links followed so far */
+ const char *zIn = zPath; /* Input path for each iteration of loop */
+ char *zDel = 0;
+
+ assert( pVfs->mxPathname==MAX_PATHNAME );
+ UNUSED_PARAMETER(pVfs);
+
+ /* It's odd to simulate an io-error here, but really this is just
+ ** using the io-error infrastructure to test that SQLite handles this
+ ** function failing. This function could fail if, for example, the
+ ** current working directory has been unlinked.
+ */
+ SimulateIOError( return SQLITE_ERROR );
+
+ do {
+
+ /* Call stat() on path zIn. Set bLink to true if the path is a symbolic
+ ** link, or false otherwise. */
+ int bLink = 0;
+ struct stat buf;
+ if( osLstat(zIn, &buf)!=0 ){
+ if( errno!=ENOENT ){
+ rc = unixLogError(SQLITE_CANTOPEN_BKPT, "lstat", zIn);
+ }
+ }else{
+ bLink = S_ISLNK(buf.st_mode);
+ }
+
+ if( bLink ){
+ if( zDel==0 ){
+ zDel = sqlite3_malloc(nOut);
+ if( zDel==0 ) rc = SQLITE_NOMEM_BKPT;
+ }else if( ++nLink>SQLITE_MAX_SYMLINKS ){
+ rc = SQLITE_CANTOPEN_BKPT;
+ }
+
+ if( rc==SQLITE_OK ){
+ nByte = osReadlink(zIn, zDel, nOut-1);
+ if( nByte<0 ){
+ rc = unixLogError(SQLITE_CANTOPEN_BKPT, "readlink", zIn);
+ }else{
+ if( zDel[0]!='/' ){
+ int n;
+ for(n = sqlite3Strlen30(zIn); n>0 && zIn[n-1]!='/'; n--);
+ if( nByte+n+1>nOut ){
+ rc = SQLITE_CANTOPEN_BKPT;
+ }else{
+ memmove(&zDel[n], zDel, nByte+1);
+ memcpy(zDel, zIn, n);
+ nByte += n;
+ }
+ }
+ zDel[nByte] = '\0';
+ }
+ }
+
+ zIn = zDel;
+ }
+
+ assert( rc!=SQLITE_OK || zIn!=zOut || zIn[0]=='/' );
+ if( rc==SQLITE_OK && zIn!=zOut ){
+ rc = mkFullPathname(zIn, zOut, nOut);
+ }
+ if( bLink==0 ) break;
+ zIn = zOut;
+ }while( rc==SQLITE_OK );
+
+ sqlite3_free(zDel);
+ return rc;
+#endif /* HAVE_READLINK && HAVE_LSTAT */
+}
+
+
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+/*
+** Interfaces for opening a shared library, finding entry points
+** within the shared library, and closing the shared library.
+*/
+#include
+static void *unixDlOpen(sqlite3_vfs *NotUsed, const char *zFilename){
+ UNUSED_PARAMETER(NotUsed);
+ return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
+}
+
+/*
+** SQLite calls this function immediately after a call to unixDlSym() or
+** unixDlOpen() fails (returns a null pointer). If a more detailed error
+** message is available, it is written to zBufOut. If no error message
+** is available, zBufOut is left unmodified and SQLite uses a default
+** error message.
+*/
+static void unixDlError(sqlite3_vfs *NotUsed, int nBuf, char *zBufOut){
+ const char *zErr;
+ UNUSED_PARAMETER(NotUsed);
+ unixEnterMutex();
+ zErr = dlerror();
+ if( zErr ){
+ sqlite3_snprintf(nBuf, zBufOut, "%s", zErr);
+ }
+ unixLeaveMutex();
+}
+static void (*unixDlSym(sqlite3_vfs *NotUsed, void *p, const char*zSym))(void){
+ /*
+ ** GCC with -pedantic-errors says that C90 does not allow a void* to be
+ ** cast into a pointer to a function. And yet the library dlsym() routine
+ ** returns a void* which is really a pointer to a function. So how do we
+ ** use dlsym() with -pedantic-errors?
+ **
+ ** Variable x below is defined to be a pointer to a function taking
+ ** parameters void* and const char* and returning a pointer to a function.
+ ** We initialize x by assigning it a pointer to the dlsym() function.
+ ** (That assignment requires a cast.) Then we call the function that
+ ** x points to.
+ **
+ ** This work-around is unlikely to work correctly on any system where
+ ** you really cannot cast a function pointer into void*. But then, on the
+ ** other hand, dlsym() will not work on such a system either, so we have
+ ** not really lost anything.
+ */
+ void (*(*x)(void*,const char*))(void);
+ UNUSED_PARAMETER(NotUsed);
+ x = (void(*(*)(void*,const char*))(void))dlsym;
+ return (*x)(p, zSym);
+}
+static void unixDlClose(sqlite3_vfs *NotUsed, void *pHandle){
+ UNUSED_PARAMETER(NotUsed);
+ dlclose(pHandle);
+}
+#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
+ #define unixDlOpen 0
+ #define unixDlError 0
+ #define unixDlSym 0
+ #define unixDlClose 0
+#endif
+
+/*
+** Write nBuf bytes of random data to the supplied buffer zBuf.
+*/
+static int unixRandomness(sqlite3_vfs *NotUsed, int nBuf, char *zBuf){
+ UNUSED_PARAMETER(NotUsed);
+ assert((size_t)nBuf>=(sizeof(time_t)+sizeof(int)));
+
+ /* We have to initialize zBuf to prevent valgrind from reporting
+ ** errors. The reports issued by valgrind are incorrect - we would
+ ** prefer that the randomness be increased by making use of the
+ ** uninitialized space in zBuf - but valgrind errors tend to worry
+ ** some users. Rather than argue, it seems easier just to initialize
+ ** the whole array and silence valgrind, even if that means less randomness
+ ** in the random seed.
+ **
+ ** When testing, initializing zBuf[] to zero is all we do. That means
+ ** that we always use the same random number sequence. This makes the
+ ** tests repeatable.
+ */
+ memset(zBuf, 0, nBuf);
+ randomnessPid = osGetpid(0);
+#if !defined(SQLITE_TEST) && !defined(SQLITE_OMIT_RANDOMNESS)
+ {
+ int fd, got;
+ fd = robust_open("/dev/urandom", O_RDONLY, 0);
+ if( fd<0 ){
+ time_t t;
+ time(&t);
+ memcpy(zBuf, &t, sizeof(t));
+ memcpy(&zBuf[sizeof(t)], &randomnessPid, sizeof(randomnessPid));
+ assert( sizeof(t)+sizeof(randomnessPid)<=(size_t)nBuf );
+ nBuf = sizeof(t) + sizeof(randomnessPid);
+ }else{
+ do{ got = osRead(fd, zBuf, nBuf); }while( got<0 && errno==EINTR );
+ robust_close(0, fd, __LINE__);
+ }
+ }
+#endif
+ return nBuf;
+}
+
+
+/*
+** Sleep for a little while. Return the amount of time slept.
+** The argument is the number of microseconds we want to sleep.
+** The return value is the number of microseconds of sleep actually
+** requested from the underlying operating system, a number which
+** might be greater than or equal to the argument, but not less
+** than the argument.
+*/
+static int unixSleep(sqlite3_vfs *NotUsed, int microseconds){
+#if OS_VXWORKS
+ struct timespec sp;
+
+ sp.tv_sec = microseconds / 1000000;
+ sp.tv_nsec = (microseconds % 1000000) * 1000;
+ nanosleep(&sp, NULL);
+ UNUSED_PARAMETER(NotUsed);
+ return microseconds;
+#elif defined(HAVE_USLEEP) && HAVE_USLEEP
+ usleep(microseconds);
+ UNUSED_PARAMETER(NotUsed);
+ return microseconds;
+#else
+ int seconds = (microseconds+999999)/1000000;
+ sleep(seconds);
+ UNUSED_PARAMETER(NotUsed);
+ return seconds*1000000;
+#endif
+}
+
+/*
+** The following variable, if set to a non-zero value, is interpreted as
+** the number of seconds since 1970 and is used to set the result of
+** sqlite3OsCurrentTime() during testing.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_current_time = 0; /* Fake system time in seconds since 1970. */
+#endif
+
+/*
+** Find the current time (in Universal Coordinated Time). Write into *piNow
+** the current time and date as a Julian Day number times 86_400_000. In
+** other words, write into *piNow the number of milliseconds since the Julian
+** epoch of noon in Greenwich on November 24, 4714 B.C according to the
+** proleptic Gregorian calendar.
+**
+** On success, return SQLITE_OK. Return SQLITE_ERROR if the time and date
+** cannot be found.
+*/
+static int unixCurrentTimeInt64(sqlite3_vfs *NotUsed, sqlite3_int64 *piNow){
+ static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
+ int rc = SQLITE_OK;
+#if defined(NO_GETTOD)
+ time_t t;
+ time(&t);
+ *piNow = ((sqlite3_int64)t)*1000 + unixEpoch;
+#elif OS_VXWORKS
+ struct timespec sNow;
+ clock_gettime(CLOCK_REALTIME, &sNow);
+ *piNow = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_nsec/1000000;
+#else
+ struct timeval sNow;
+ (void)gettimeofday(&sNow, 0); /* Cannot fail given valid arguments */
+ *piNow = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_usec/1000;
+#endif
+
+#ifdef SQLITE_TEST
+ if( sqlite3_current_time ){
+ *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
+ }
+#endif
+ UNUSED_PARAMETER(NotUsed);
+ return rc;
+}
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Find the current time (in Universal Coordinated Time). Write the
+** current time and date as a Julian Day number into *prNow and
+** return 0. Return 1 if the time and date cannot be found.
+*/
+static int unixCurrentTime(sqlite3_vfs *NotUsed, double *prNow){
+ sqlite3_int64 i = 0;
+ int rc;
+ UNUSED_PARAMETER(NotUsed);
+ rc = unixCurrentTimeInt64(0, &i);
+ *prNow = i/86400000.0;
+ return rc;
+}
+#else
+# define unixCurrentTime 0
+#endif
+
+/*
+** The xGetLastError() method is designed to return a better
+** low-level error message when operating-system problems come up
+** during SQLite operation. Only the integer return code is currently
+** used.
+*/
+static int unixGetLastError(sqlite3_vfs *NotUsed, int NotUsed2, char *NotUsed3){
+ UNUSED_PARAMETER(NotUsed);
+ UNUSED_PARAMETER(NotUsed2);
+ UNUSED_PARAMETER(NotUsed3);
+ return errno;
+}
+
+
+/*
+************************ End of sqlite3_vfs methods ***************************
+******************************************************************************/
+
+/******************************************************************************
+************************** Begin Proxy Locking ********************************
+**
+** Proxy locking is a "uber-locking-method" in this sense: It uses the
+** other locking methods on secondary lock files. Proxy locking is a
+** meta-layer over top of the primitive locking implemented above. For
+** this reason, the division that implements of proxy locking is deferred
+** until late in the file (here) after all of the other I/O methods have
+** been defined - so that the primitive locking methods are available
+** as services to help with the implementation of proxy locking.
+**
+****
+**
+** The default locking schemes in SQLite use byte-range locks on the
+** database file to coordinate safe, concurrent access by multiple readers
+** and writers [http://sqlite.org/lockingv3.html]. The five file locking
+** states (UNLOCKED, PENDING, SHARED, RESERVED, EXCLUSIVE) are implemented
+** as POSIX read & write locks over fixed set of locations (via fsctl),
+** on AFP and SMB only exclusive byte-range locks are available via fsctl
+** with _IOWR('z', 23, struct ByteRangeLockPB2) to track the same 5 states.
+** To simulate a F_RDLCK on the shared range, on AFP a randomly selected
+** address in the shared range is taken for a SHARED lock, the entire
+** shared range is taken for an EXCLUSIVE lock):
+**
+** PENDING_BYTE 0x40000000
+** RESERVED_BYTE 0x40000001
+** SHARED_RANGE 0x40000002 -> 0x40000200
+**
+** This works well on the local file system, but shows a nearly 100x
+** slowdown in read performance on AFP because the AFP client disables
+** the read cache when byte-range locks are present. Enabling the read
+** cache exposes a cache coherency problem that is present on all OS X
+** supported network file systems. NFS and AFP both observe the
+** close-to-open semantics for ensuring cache coherency
+** [http://nfs.sourceforge.net/#faq_a8], which does not effectively
+** address the requirements for concurrent database access by multiple
+** readers and writers
+** [http://www.nabble.com/SQLite-on-NFS-cache-coherency-td15655701.html].
+**
+** To address the performance and cache coherency issues, proxy file locking
+** changes the way database access is controlled by limiting access to a
+** single host at a time and moving file locks off of the database file
+** and onto a proxy file on the local file system.
+**
+**
+** Using proxy locks
+** -----------------
+**
+** C APIs
+**
+** sqlite3_file_control(db, dbname, SQLITE_FCNTL_SET_LOCKPROXYFILE,
+** | ":auto:");
+** sqlite3_file_control(db, dbname, SQLITE_FCNTL_GET_LOCKPROXYFILE,
+** &);
+**
+**
+** SQL pragmas
+**
+** PRAGMA [database.]lock_proxy_file= | :auto:
+** PRAGMA [database.]lock_proxy_file
+**
+** Specifying ":auto:" means that if there is a conch file with a matching
+** host ID in it, the proxy path in the conch file will be used, otherwise
+** a proxy path based on the user's temp dir
+** (via confstr(_CS_DARWIN_USER_TEMP_DIR,...)) will be used and the
+** actual proxy file name is generated from the name and path of the
+** database file. For example:
+**
+** For database path "/Users/me/foo.db"
+** The lock path will be "/sqliteplocks/_Users_me_foo.db:auto:")
+**
+** Once a lock proxy is configured for a database connection, it can not
+** be removed, however it may be switched to a different proxy path via
+** the above APIs (assuming the conch file is not being held by another
+** connection or process).
+**
+**
+** How proxy locking works
+** -----------------------
+**
+** Proxy file locking relies primarily on two new supporting files:
+**
+** * conch file to limit access to the database file to a single host
+** at a time
+**
+** * proxy file to act as a proxy for the advisory locks normally
+** taken on the database
+**
+** The conch file - to use a proxy file, sqlite must first "hold the conch"
+** by taking an sqlite-style shared lock on the conch file, reading the
+** contents and comparing the host's unique host ID (see below) and lock
+** proxy path against the values stored in the conch. The conch file is
+** stored in the same directory as the database file and the file name
+** is patterned after the database file name as ".-conch".
+** If the conch file does not exist, or its contents do not match the
+** host ID and/or proxy path, then the lock is escalated to an exclusive
+** lock and the conch file contents is updated with the host ID and proxy
+** path and the lock is downgraded to a shared lock again. If the conch
+** is held by another process (with a shared lock), the exclusive lock
+** will fail and SQLITE_BUSY is returned.
+**
+** The proxy file - a single-byte file used for all advisory file locks
+** normally taken on the database file. This allows for safe sharing
+** of the database file for multiple readers and writers on the same
+** host (the conch ensures that they all use the same local lock file).
+**
+** Requesting the lock proxy does not immediately take the conch, it is
+** only taken when the first request to lock database file is made.
+** This matches the semantics of the traditional locking behavior, where
+** opening a connection to a database file does not take a lock on it.
+** The shared lock and an open file descriptor are maintained until
+** the connection to the database is closed.
+**
+** The proxy file and the lock file are never deleted so they only need
+** to be created the first time they are used.
+**
+** Configuration options
+** ---------------------
+**
+** SQLITE_PREFER_PROXY_LOCKING
+**
+** Database files accessed on non-local file systems are
+** automatically configured for proxy locking, lock files are
+** named automatically using the same logic as
+** PRAGMA lock_proxy_file=":auto:"
+**
+** SQLITE_PROXY_DEBUG
+**
+** Enables the logging of error messages during host id file
+** retrieval and creation
+**
+** LOCKPROXYDIR
+**
+** Overrides the default directory used for lock proxy files that
+** are named automatically via the ":auto:" setting
+**
+** SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
+**
+** Permissions to use when creating a directory for storing the
+** lock proxy files, only used when LOCKPROXYDIR is not set.
+**
+**
+** As mentioned above, when compiled with SQLITE_PREFER_PROXY_LOCKING,
+** setting the environment variable SQLITE_FORCE_PROXY_LOCKING to 1 will
+** force proxy locking to be used for every database file opened, and 0
+** will force automatic proxy locking to be disabled for all database
+** files (explicitly calling the SQLITE_FCNTL_SET_LOCKPROXYFILE pragma or
+** sqlite_file_control API is not affected by SQLITE_FORCE_PROXY_LOCKING).
+*/
+
+/*
+** Proxy locking is only available on MacOSX
+*/
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+
+/*
+** The proxyLockingContext has the path and file structures for the remote
+** and local proxy files in it
+*/
+typedef struct proxyLockingContext proxyLockingContext;
+struct proxyLockingContext {
+ unixFile *conchFile; /* Open conch file */
+ char *conchFilePath; /* Name of the conch file */
+ unixFile *lockProxy; /* Open proxy lock file */
+ char *lockProxyPath; /* Name of the proxy lock file */
+ char *dbPath; /* Name of the open file */
+ int conchHeld; /* 1 if the conch is held, -1 if lockless */
+ int nFails; /* Number of conch taking failures */
+ void *oldLockingContext; /* Original lockingcontext to restore on close */
+ sqlite3_io_methods const *pOldMethod; /* Original I/O methods for close */
+};
+
+/*
+** The proxy lock file path for the database at dbPath is written into lPath,
+** which must point to valid, writable memory large enough for a maxLen length
+** file path.
+*/
+static int proxyGetLockPath(const char *dbPath, char *lPath, size_t maxLen){
+ int len;
+ int dbLen;
+ int i;
+
+#ifdef LOCKPROXYDIR
+ len = strlcpy(lPath, LOCKPROXYDIR, maxLen);
+#else
+# ifdef _CS_DARWIN_USER_TEMP_DIR
+ {
+ if( !confstr(_CS_DARWIN_USER_TEMP_DIR, lPath, maxLen) ){
+ OSTRACE(("GETLOCKPATH failed %s errno=%d pid=%d\n",
+ lPath, errno, osGetpid(0)));
+ return SQLITE_IOERR_LOCK;
+ }
+ len = strlcat(lPath, "sqliteplocks", maxLen);
+ }
+# else
+ len = strlcpy(lPath, "/tmp/", maxLen);
+# endif
+#endif
+
+ if( lPath[len-1]!='/' ){
+ len = strlcat(lPath, "/", maxLen);
+ }
+
+ /* transform the db path to a unique cache name */
+ dbLen = (int)strlen(dbPath);
+ for( i=0; i 0) ){
+ /* only mkdir if leaf dir != "." or "/" or ".." */
+ if( i-start>2 || (i-start==1 && buf[start] != '.' && buf[start] != '/')
+ || (i-start==2 && buf[start] != '.' && buf[start+1] != '.') ){
+ buf[i]='\0';
+ if( osMkdir(buf, SQLITE_DEFAULT_PROXYDIR_PERMISSIONS) ){
+ int err=errno;
+ if( err!=EEXIST ) {
+ OSTRACE(("CREATELOCKPATH FAILED creating %s, "
+ "'%s' proxy lock path=%s pid=%d\n",
+ buf, strerror(err), lockPath, osGetpid(0)));
+ return err;
+ }
+ }
+ }
+ start=i+1;
+ }
+ buf[i] = lockPath[i];
+ }
+ OSTRACE(("CREATELOCKPATH proxy lock path=%s pid=%d\n",lockPath,osGetpid(0)));
+ return 0;
+}
+
+/*
+** Create a new VFS file descriptor (stored in memory obtained from
+** sqlite3_malloc) and open the file named "path" in the file descriptor.
+**
+** The caller is responsible not only for closing the file descriptor
+** but also for freeing the memory associated with the file descriptor.
+*/
+static int proxyCreateUnixFile(
+ const char *path, /* path for the new unixFile */
+ unixFile **ppFile, /* unixFile created and returned by ref */
+ int islockfile /* if non zero missing dirs will be created */
+) {
+ int fd = -1;
+ unixFile *pNew;
+ int rc = SQLITE_OK;
+ int openFlags = O_RDWR | O_CREAT;
+ sqlite3_vfs dummyVfs;
+ int terrno = 0;
+ UnixUnusedFd *pUnused = NULL;
+
+ /* 1. first try to open/create the file
+ ** 2. if that fails, and this is a lock file (not-conch), try creating
+ ** the parent directories and then try again.
+ ** 3. if that fails, try to open the file read-only
+ ** otherwise return BUSY (if lock file) or CANTOPEN for the conch file
+ */
+ pUnused = findReusableFd(path, openFlags);
+ if( pUnused ){
+ fd = pUnused->fd;
+ }else{
+ pUnused = sqlite3_malloc64(sizeof(*pUnused));
+ if( !pUnused ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ }
+ if( fd<0 ){
+ fd = robust_open(path, openFlags, 0);
+ terrno = errno;
+ if( fd<0 && errno==ENOENT && islockfile ){
+ if( proxyCreateLockPath(path) == SQLITE_OK ){
+ fd = robust_open(path, openFlags, 0);
+ }
+ }
+ }
+ if( fd<0 ){
+ openFlags = O_RDONLY;
+ fd = robust_open(path, openFlags, 0);
+ terrno = errno;
+ }
+ if( fd<0 ){
+ if( islockfile ){
+ return SQLITE_BUSY;
+ }
+ switch (terrno) {
+ case EACCES:
+ return SQLITE_PERM;
+ case EIO:
+ return SQLITE_IOERR_LOCK; /* even though it is the conch */
+ default:
+ return SQLITE_CANTOPEN_BKPT;
+ }
+ }
+
+ pNew = (unixFile *)sqlite3_malloc64(sizeof(*pNew));
+ if( pNew==NULL ){
+ rc = SQLITE_NOMEM_BKPT;
+ goto end_create_proxy;
+ }
+ memset(pNew, 0, sizeof(unixFile));
+ pNew->openFlags = openFlags;
+ memset(&dummyVfs, 0, sizeof(dummyVfs));
+ dummyVfs.pAppData = (void*)&autolockIoFinder;
+ dummyVfs.zName = "dummy";
+ pUnused->fd = fd;
+ pUnused->flags = openFlags;
+ pNew->pPreallocatedUnused = pUnused;
+
+ rc = fillInUnixFile(&dummyVfs, fd, (sqlite3_file*)pNew, path, 0);
+ if( rc==SQLITE_OK ){
+ *ppFile = pNew;
+ return SQLITE_OK;
+ }
+end_create_proxy:
+ robust_close(pNew, fd, __LINE__);
+ sqlite3_free(pNew);
+ sqlite3_free(pUnused);
+ return rc;
+}
+
+#ifdef SQLITE_TEST
+/* simulate multiple hosts by creating unique hostid file paths */
+SQLITE_API int sqlite3_hostid_num = 0;
+#endif
+
+#define PROXY_HOSTIDLEN 16 /* conch file host id length */
+
+#ifdef HAVE_GETHOSTUUID
+/* Not always defined in the headers as it ought to be */
+extern int gethostuuid(uuid_t id, const struct timespec *wait);
+#endif
+
+/* get the host ID via gethostuuid(), pHostID must point to PROXY_HOSTIDLEN
+** bytes of writable memory.
+*/
+static int proxyGetHostID(unsigned char *pHostID, int *pError){
+ assert(PROXY_HOSTIDLEN == sizeof(uuid_t));
+ memset(pHostID, 0, PROXY_HOSTIDLEN);
+#ifdef HAVE_GETHOSTUUID
+ {
+ struct timespec timeout = {1, 0}; /* 1 sec timeout */
+ if( gethostuuid(pHostID, &timeout) ){
+ int err = errno;
+ if( pError ){
+ *pError = err;
+ }
+ return SQLITE_IOERR;
+ }
+ }
+#else
+ UNUSED_PARAMETER(pError);
+#endif
+#ifdef SQLITE_TEST
+ /* simulate multiple hosts by creating unique hostid file paths */
+ if( sqlite3_hostid_num != 0){
+ pHostID[0] = (char)(pHostID[0] + (char)(sqlite3_hostid_num & 0xFF));
+ }
+#endif
+
+ return SQLITE_OK;
+}
+
+/* The conch file contains the header, host id and lock file path
+ */
+#define PROXY_CONCHVERSION 2 /* 1-byte header, 16-byte host id, path */
+#define PROXY_HEADERLEN 1 /* conch file header length */
+#define PROXY_PATHINDEX (PROXY_HEADERLEN+PROXY_HOSTIDLEN)
+#define PROXY_MAXCONCHLEN (PROXY_HEADERLEN+PROXY_HOSTIDLEN+MAXPATHLEN)
+
+/*
+** Takes an open conch file, copies the contents to a new path and then moves
+** it back. The newly created file's file descriptor is assigned to the
+** conch file structure and finally the original conch file descriptor is
+** closed. Returns zero if successful.
+*/
+static int proxyBreakConchLock(unixFile *pFile, uuid_t myHostID){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ unixFile *conchFile = pCtx->conchFile;
+ char tPath[MAXPATHLEN];
+ char buf[PROXY_MAXCONCHLEN];
+ char *cPath = pCtx->conchFilePath;
+ size_t readLen = 0;
+ size_t pathLen = 0;
+ char errmsg[64] = "";
+ int fd = -1;
+ int rc = -1;
+ UNUSED_PARAMETER(myHostID);
+
+ /* create a new path by replace the trailing '-conch' with '-break' */
+ pathLen = strlcpy(tPath, cPath, MAXPATHLEN);
+ if( pathLen>MAXPATHLEN || pathLen<6 ||
+ (strlcpy(&tPath[pathLen-5], "break", 6) != 5) ){
+ sqlite3_snprintf(sizeof(errmsg),errmsg,"path error (len %d)",(int)pathLen);
+ goto end_breaklock;
+ }
+ /* read the conch content */
+ readLen = osPread(conchFile->h, buf, PROXY_MAXCONCHLEN, 0);
+ if( readLenh, __LINE__);
+ conchFile->h = fd;
+ conchFile->openFlags = O_RDWR | O_CREAT;
+
+end_breaklock:
+ if( rc ){
+ if( fd>=0 ){
+ osUnlink(tPath);
+ robust_close(pFile, fd, __LINE__);
+ }
+ fprintf(stderr, "failed to break stale lock on %s, %s\n", cPath, errmsg);
+ }
+ return rc;
+}
+
+/* Take the requested lock on the conch file and break a stale lock if the
+** host id matches.
+*/
+static int proxyConchLock(unixFile *pFile, uuid_t myHostID, int lockType){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ unixFile *conchFile = pCtx->conchFile;
+ int rc = SQLITE_OK;
+ int nTries = 0;
+ struct timespec conchModTime;
+
+ memset(&conchModTime, 0, sizeof(conchModTime));
+ do {
+ rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, lockType);
+ nTries ++;
+ if( rc==SQLITE_BUSY ){
+ /* If the lock failed (busy):
+ * 1st try: get the mod time of the conch, wait 0.5s and try again.
+ * 2nd try: fail if the mod time changed or host id is different, wait
+ * 10 sec and try again
+ * 3rd try: break the lock unless the mod time has changed.
+ */
+ struct stat buf;
+ if( osFstat(conchFile->h, &buf) ){
+ storeLastErrno(pFile, errno);
+ return SQLITE_IOERR_LOCK;
+ }
+
+ if( nTries==1 ){
+ conchModTime = buf.st_mtimespec;
+ usleep(500000); /* wait 0.5 sec and try the lock again*/
+ continue;
+ }
+
+ assert( nTries>1 );
+ if( conchModTime.tv_sec != buf.st_mtimespec.tv_sec ||
+ conchModTime.tv_nsec != buf.st_mtimespec.tv_nsec ){
+ return SQLITE_BUSY;
+ }
+
+ if( nTries==2 ){
+ char tBuf[PROXY_MAXCONCHLEN];
+ int len = osPread(conchFile->h, tBuf, PROXY_MAXCONCHLEN, 0);
+ if( len<0 ){
+ storeLastErrno(pFile, errno);
+ return SQLITE_IOERR_LOCK;
+ }
+ if( len>PROXY_PATHINDEX && tBuf[0]==(char)PROXY_CONCHVERSION){
+ /* don't break the lock if the host id doesn't match */
+ if( 0!=memcmp(&tBuf[PROXY_HEADERLEN], myHostID, PROXY_HOSTIDLEN) ){
+ return SQLITE_BUSY;
+ }
+ }else{
+ /* don't break the lock on short read or a version mismatch */
+ return SQLITE_BUSY;
+ }
+ usleep(10000000); /* wait 10 sec and try the lock again */
+ continue;
+ }
+
+ assert( nTries==3 );
+ if( 0==proxyBreakConchLock(pFile, myHostID) ){
+ rc = SQLITE_OK;
+ if( lockType==EXCLUSIVE_LOCK ){
+ rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, SHARED_LOCK);
+ }
+ if( !rc ){
+ rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, lockType);
+ }
+ }
+ }
+ } while( rc==SQLITE_BUSY && nTries<3 );
+
+ return rc;
+}
+
+/* Takes the conch by taking a shared lock and read the contents conch, if
+** lockPath is non-NULL, the host ID and lock file path must match. A NULL
+** lockPath means that the lockPath in the conch file will be used if the
+** host IDs match, or a new lock path will be generated automatically
+** and written to the conch file.
+*/
+static int proxyTakeConch(unixFile *pFile){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+
+ if( pCtx->conchHeld!=0 ){
+ return SQLITE_OK;
+ }else{
+ unixFile *conchFile = pCtx->conchFile;
+ uuid_t myHostID;
+ int pError = 0;
+ char readBuf[PROXY_MAXCONCHLEN];
+ char lockPath[MAXPATHLEN];
+ char *tempLockPath = NULL;
+ int rc = SQLITE_OK;
+ int createConch = 0;
+ int hostIdMatch = 0;
+ int readLen = 0;
+ int tryOldLockPath = 0;
+ int forceNewLockPath = 0;
+
+ OSTRACE(("TAKECONCH %d for %s pid=%d\n", conchFile->h,
+ (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"),
+ osGetpid(0)));
+
+ rc = proxyGetHostID(myHostID, &pError);
+ if( (rc&0xff)==SQLITE_IOERR ){
+ storeLastErrno(pFile, pError);
+ goto end_takeconch;
+ }
+ rc = proxyConchLock(pFile, myHostID, SHARED_LOCK);
+ if( rc!=SQLITE_OK ){
+ goto end_takeconch;
+ }
+ /* read the existing conch file */
+ readLen = seekAndRead((unixFile*)conchFile, 0, readBuf, PROXY_MAXCONCHLEN);
+ if( readLen<0 ){
+ /* I/O error: lastErrno set by seekAndRead */
+ storeLastErrno(pFile, conchFile->lastErrno);
+ rc = SQLITE_IOERR_READ;
+ goto end_takeconch;
+ }else if( readLen<=(PROXY_HEADERLEN+PROXY_HOSTIDLEN) ||
+ readBuf[0]!=(char)PROXY_CONCHVERSION ){
+ /* a short read or version format mismatch means we need to create a new
+ ** conch file.
+ */
+ createConch = 1;
+ }
+ /* if the host id matches and the lock path already exists in the conch
+ ** we'll try to use the path there, if we can't open that path, we'll
+ ** retry with a new auto-generated path
+ */
+ do { /* in case we need to try again for an :auto: named lock file */
+
+ if( !createConch && !forceNewLockPath ){
+ hostIdMatch = !memcmp(&readBuf[PROXY_HEADERLEN], myHostID,
+ PROXY_HOSTIDLEN);
+ /* if the conch has data compare the contents */
+ if( !pCtx->lockProxyPath ){
+ /* for auto-named local lock file, just check the host ID and we'll
+ ** use the local lock file path that's already in there
+ */
+ if( hostIdMatch ){
+ size_t pathLen = (readLen - PROXY_PATHINDEX);
+
+ if( pathLen>=MAXPATHLEN ){
+ pathLen=MAXPATHLEN-1;
+ }
+ memcpy(lockPath, &readBuf[PROXY_PATHINDEX], pathLen);
+ lockPath[pathLen] = 0;
+ tempLockPath = lockPath;
+ tryOldLockPath = 1;
+ /* create a copy of the lock path if the conch is taken */
+ goto end_takeconch;
+ }
+ }else if( hostIdMatch
+ && !strncmp(pCtx->lockProxyPath, &readBuf[PROXY_PATHINDEX],
+ readLen-PROXY_PATHINDEX)
+ ){
+ /* conch host and lock path match */
+ goto end_takeconch;
+ }
+ }
+
+ /* if the conch isn't writable and doesn't match, we can't take it */
+ if( (conchFile->openFlags&O_RDWR) == 0 ){
+ rc = SQLITE_BUSY;
+ goto end_takeconch;
+ }
+
+ /* either the conch didn't match or we need to create a new one */
+ if( !pCtx->lockProxyPath ){
+ proxyGetLockPath(pCtx->dbPath, lockPath, MAXPATHLEN);
+ tempLockPath = lockPath;
+ /* create a copy of the lock path _only_ if the conch is taken */
+ }
+
+ /* update conch with host and path (this will fail if other process
+ ** has a shared lock already), if the host id matches, use the big
+ ** stick.
+ */
+ futimes(conchFile->h, NULL);
+ if( hostIdMatch && !createConch ){
+ if( conchFile->pInode && conchFile->pInode->nShared>1 ){
+ /* We are trying for an exclusive lock but another thread in this
+ ** same process is still holding a shared lock. */
+ rc = SQLITE_BUSY;
+ } else {
+ rc = proxyConchLock(pFile, myHostID, EXCLUSIVE_LOCK);
+ }
+ }else{
+ rc = proxyConchLock(pFile, myHostID, EXCLUSIVE_LOCK);
+ }
+ if( rc==SQLITE_OK ){
+ char writeBuffer[PROXY_MAXCONCHLEN];
+ int writeSize = 0;
+
+ writeBuffer[0] = (char)PROXY_CONCHVERSION;
+ memcpy(&writeBuffer[PROXY_HEADERLEN], myHostID, PROXY_HOSTIDLEN);
+ if( pCtx->lockProxyPath!=NULL ){
+ strlcpy(&writeBuffer[PROXY_PATHINDEX], pCtx->lockProxyPath,
+ MAXPATHLEN);
+ }else{
+ strlcpy(&writeBuffer[PROXY_PATHINDEX], tempLockPath, MAXPATHLEN);
+ }
+ writeSize = PROXY_PATHINDEX + strlen(&writeBuffer[PROXY_PATHINDEX]);
+ robust_ftruncate(conchFile->h, writeSize);
+ rc = unixWrite((sqlite3_file *)conchFile, writeBuffer, writeSize, 0);
+ full_fsync(conchFile->h,0,0);
+ /* If we created a new conch file (not just updated the contents of a
+ ** valid conch file), try to match the permissions of the database
+ */
+ if( rc==SQLITE_OK && createConch ){
+ struct stat buf;
+ int err = osFstat(pFile->h, &buf);
+ if( err==0 ){
+ mode_t cmode = buf.st_mode&(S_IRUSR|S_IWUSR | S_IRGRP|S_IWGRP |
+ S_IROTH|S_IWOTH);
+ /* try to match the database file R/W permissions, ignore failure */
+#ifndef SQLITE_PROXY_DEBUG
+ osFchmod(conchFile->h, cmode);
+#else
+ do{
+ rc = osFchmod(conchFile->h, cmode);
+ }while( rc==(-1) && errno==EINTR );
+ if( rc!=0 ){
+ int code = errno;
+ fprintf(stderr, "fchmod %o FAILED with %d %s\n",
+ cmode, code, strerror(code));
+ } else {
+ fprintf(stderr, "fchmod %o SUCCEDED\n",cmode);
+ }
+ }else{
+ int code = errno;
+ fprintf(stderr, "STAT FAILED[%d] with %d %s\n",
+ err, code, strerror(code));
+#endif
+ }
+ }
+ }
+ conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, SHARED_LOCK);
+
+ end_takeconch:
+ OSTRACE(("TRANSPROXY: CLOSE %d\n", pFile->h));
+ if( rc==SQLITE_OK && pFile->openFlags ){
+ int fd;
+ if( pFile->h>=0 ){
+ robust_close(pFile, pFile->h, __LINE__);
+ }
+ pFile->h = -1;
+ fd = robust_open(pCtx->dbPath, pFile->openFlags, 0);
+ OSTRACE(("TRANSPROXY: OPEN %d\n", fd));
+ if( fd>=0 ){
+ pFile->h = fd;
+ }else{
+ rc=SQLITE_CANTOPEN_BKPT; /* SQLITE_BUSY? proxyTakeConch called
+ during locking */
+ }
+ }
+ if( rc==SQLITE_OK && !pCtx->lockProxy ){
+ char *path = tempLockPath ? tempLockPath : pCtx->lockProxyPath;
+ rc = proxyCreateUnixFile(path, &pCtx->lockProxy, 1);
+ if( rc!=SQLITE_OK && rc!=SQLITE_NOMEM && tryOldLockPath ){
+ /* we couldn't create the proxy lock file with the old lock file path
+ ** so try again via auto-naming
+ */
+ forceNewLockPath = 1;
+ tryOldLockPath = 0;
+ continue; /* go back to the do {} while start point, try again */
+ }
+ }
+ if( rc==SQLITE_OK ){
+ /* Need to make a copy of path if we extracted the value
+ ** from the conch file or the path was allocated on the stack
+ */
+ if( tempLockPath ){
+ pCtx->lockProxyPath = sqlite3DbStrDup(0, tempLockPath);
+ if( !pCtx->lockProxyPath ){
+ rc = SQLITE_NOMEM_BKPT;
+ }
+ }
+ }
+ if( rc==SQLITE_OK ){
+ pCtx->conchHeld = 1;
+
+ if( pCtx->lockProxy->pMethod == &afpIoMethods ){
+ afpLockingContext *afpCtx;
+ afpCtx = (afpLockingContext *)pCtx->lockProxy->lockingContext;
+ afpCtx->dbPath = pCtx->lockProxyPath;
+ }
+ } else {
+ conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
+ }
+ OSTRACE(("TAKECONCH %d %s\n", conchFile->h,
+ rc==SQLITE_OK?"ok":"failed"));
+ return rc;
+ } while (1); /* in case we need to retry the :auto: lock file -
+ ** we should never get here except via the 'continue' call. */
+ }
+}
+
+/*
+** If pFile holds a lock on a conch file, then release that lock.
+*/
+static int proxyReleaseConch(unixFile *pFile){
+ int rc = SQLITE_OK; /* Subroutine return code */
+ proxyLockingContext *pCtx; /* The locking context for the proxy lock */
+ unixFile *conchFile; /* Name of the conch file */
+
+ pCtx = (proxyLockingContext *)pFile->lockingContext;
+ conchFile = pCtx->conchFile;
+ OSTRACE(("RELEASECONCH %d for %s pid=%d\n", conchFile->h,
+ (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"),
+ osGetpid(0)));
+ if( pCtx->conchHeld>0 ){
+ rc = conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
+ }
+ pCtx->conchHeld = 0;
+ OSTRACE(("RELEASECONCH %d %s\n", conchFile->h,
+ (rc==SQLITE_OK ? "ok" : "failed")));
+ return rc;
+}
+
+/*
+** Given the name of a database file, compute the name of its conch file.
+** Store the conch filename in memory obtained from sqlite3_malloc64().
+** Make *pConchPath point to the new name. Return SQLITE_OK on success
+** or SQLITE_NOMEM if unable to obtain memory.
+**
+** The caller is responsible for ensuring that the allocated memory
+** space is eventually freed.
+**
+** *pConchPath is set to NULL if a memory allocation error occurs.
+*/
+static int proxyCreateConchPathname(char *dbPath, char **pConchPath){
+ int i; /* Loop counter */
+ int len = (int)strlen(dbPath); /* Length of database filename - dbPath */
+ char *conchPath; /* buffer in which to construct conch name */
+
+ /* Allocate space for the conch filename and initialize the name to
+ ** the name of the original database file. */
+ *pConchPath = conchPath = (char *)sqlite3_malloc64(len + 8);
+ if( conchPath==0 ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ memcpy(conchPath, dbPath, len+1);
+
+ /* now insert a "." before the last / character */
+ for( i=(len-1); i>=0; i-- ){
+ if( conchPath[i]=='/' ){
+ i++;
+ break;
+ }
+ }
+ conchPath[i]='.';
+ while ( ilockingContext;
+ char *oldPath = pCtx->lockProxyPath;
+ int rc = SQLITE_OK;
+
+ if( pFile->eFileLock!=NO_LOCK ){
+ return SQLITE_BUSY;
+ }
+
+ /* nothing to do if the path is NULL, :auto: or matches the existing path */
+ if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ||
+ (oldPath && !strncmp(oldPath, path, MAXPATHLEN)) ){
+ return SQLITE_OK;
+ }else{
+ unixFile *lockProxy = pCtx->lockProxy;
+ pCtx->lockProxy=NULL;
+ pCtx->conchHeld = 0;
+ if( lockProxy!=NULL ){
+ rc=lockProxy->pMethod->xClose((sqlite3_file *)lockProxy);
+ if( rc ) return rc;
+ sqlite3_free(lockProxy);
+ }
+ sqlite3_free(oldPath);
+ pCtx->lockProxyPath = sqlite3DbStrDup(0, path);
+ }
+
+ return rc;
+}
+
+/*
+** pFile is a file that has been opened by a prior xOpen call. dbPath
+** is a string buffer at least MAXPATHLEN+1 characters in size.
+**
+** This routine find the filename associated with pFile and writes it
+** int dbPath.
+*/
+static int proxyGetDbPathForUnixFile(unixFile *pFile, char *dbPath){
+#if defined(__APPLE__)
+ if( pFile->pMethod == &afpIoMethods ){
+ /* afp style keeps a reference to the db path in the filePath field
+ ** of the struct */
+ assert( (int)strlen((char*)pFile->lockingContext)<=MAXPATHLEN );
+ strlcpy(dbPath, ((afpLockingContext *)pFile->lockingContext)->dbPath,
+ MAXPATHLEN);
+ } else
+#endif
+ if( pFile->pMethod == &dotlockIoMethods ){
+ /* dot lock style uses the locking context to store the dot lock
+ ** file path */
+ int len = strlen((char *)pFile->lockingContext) - strlen(DOTLOCK_SUFFIX);
+ memcpy(dbPath, (char *)pFile->lockingContext, len + 1);
+ }else{
+ /* all other styles use the locking context to store the db file path */
+ assert( strlen((char*)pFile->lockingContext)<=MAXPATHLEN );
+ strlcpy(dbPath, (char *)pFile->lockingContext, MAXPATHLEN);
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Takes an already filled in unix file and alters it so all file locking
+** will be performed on the local proxy lock file. The following fields
+** are preserved in the locking context so that they can be restored and
+** the unix structure properly cleaned up at close time:
+** ->lockingContext
+** ->pMethod
+*/
+static int proxyTransformUnixFile(unixFile *pFile, const char *path) {
+ proxyLockingContext *pCtx;
+ char dbPath[MAXPATHLEN+1]; /* Name of the database file */
+ char *lockPath=NULL;
+ int rc = SQLITE_OK;
+
+ if( pFile->eFileLock!=NO_LOCK ){
+ return SQLITE_BUSY;
+ }
+ proxyGetDbPathForUnixFile(pFile, dbPath);
+ if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ){
+ lockPath=NULL;
+ }else{
+ lockPath=(char *)path;
+ }
+
+ OSTRACE(("TRANSPROXY %d for %s pid=%d\n", pFile->h,
+ (lockPath ? lockPath : ":auto:"), osGetpid(0)));
+
+ pCtx = sqlite3_malloc64( sizeof(*pCtx) );
+ if( pCtx==0 ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ memset(pCtx, 0, sizeof(*pCtx));
+
+ rc = proxyCreateConchPathname(dbPath, &pCtx->conchFilePath);
+ if( rc==SQLITE_OK ){
+ rc = proxyCreateUnixFile(pCtx->conchFilePath, &pCtx->conchFile, 0);
+ if( rc==SQLITE_CANTOPEN && ((pFile->openFlags&O_RDWR) == 0) ){
+ /* if (a) the open flags are not O_RDWR, (b) the conch isn't there, and
+ ** (c) the file system is read-only, then enable no-locking access.
+ ** Ugh, since O_RDONLY==0x0000 we test for !O_RDWR since unixOpen asserts
+ ** that openFlags will have only one of O_RDONLY or O_RDWR.
+ */
+ struct statfs fsInfo;
+ struct stat conchInfo;
+ int goLockless = 0;
+
+ if( osStat(pCtx->conchFilePath, &conchInfo) == -1 ) {
+ int err = errno;
+ if( (err==ENOENT) && (statfs(dbPath, &fsInfo) != -1) ){
+ goLockless = (fsInfo.f_flags&MNT_RDONLY) == MNT_RDONLY;
+ }
+ }
+ if( goLockless ){
+ pCtx->conchHeld = -1; /* read only FS/ lockless */
+ rc = SQLITE_OK;
+ }
+ }
+ }
+ if( rc==SQLITE_OK && lockPath ){
+ pCtx->lockProxyPath = sqlite3DbStrDup(0, lockPath);
+ }
+
+ if( rc==SQLITE_OK ){
+ pCtx->dbPath = sqlite3DbStrDup(0, dbPath);
+ if( pCtx->dbPath==NULL ){
+ rc = SQLITE_NOMEM_BKPT;
+ }
+ }
+ if( rc==SQLITE_OK ){
+ /* all memory is allocated, proxys are created and assigned,
+ ** switch the locking context and pMethod then return.
+ */
+ pCtx->oldLockingContext = pFile->lockingContext;
+ pFile->lockingContext = pCtx;
+ pCtx->pOldMethod = pFile->pMethod;
+ pFile->pMethod = &proxyIoMethods;
+ }else{
+ if( pCtx->conchFile ){
+ pCtx->conchFile->pMethod->xClose((sqlite3_file *)pCtx->conchFile);
+ sqlite3_free(pCtx->conchFile);
+ }
+ sqlite3DbFree(0, pCtx->lockProxyPath);
+ sqlite3_free(pCtx->conchFilePath);
+ sqlite3_free(pCtx);
+ }
+ OSTRACE(("TRANSPROXY %d %s\n", pFile->h,
+ (rc==SQLITE_OK ? "ok" : "failed")));
+ return rc;
+}
+
+
+/*
+** This routine handles sqlite3_file_control() calls that are specific
+** to proxy locking.
+*/
+static int proxyFileControl(sqlite3_file *id, int op, void *pArg){
+ switch( op ){
+ case SQLITE_FCNTL_GET_LOCKPROXYFILE: {
+ unixFile *pFile = (unixFile*)id;
+ if( pFile->pMethod == &proxyIoMethods ){
+ proxyLockingContext *pCtx = (proxyLockingContext*)pFile->lockingContext;
+ proxyTakeConch(pFile);
+ if( pCtx->lockProxyPath ){
+ *(const char **)pArg = pCtx->lockProxyPath;
+ }else{
+ *(const char **)pArg = ":auto: (not held)";
+ }
+ } else {
+ *(const char **)pArg = NULL;
+ }
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_SET_LOCKPROXYFILE: {
+ unixFile *pFile = (unixFile*)id;
+ int rc = SQLITE_OK;
+ int isProxyStyle = (pFile->pMethod == &proxyIoMethods);
+ if( pArg==NULL || (const char *)pArg==0 ){
+ if( isProxyStyle ){
+ /* turn off proxy locking - not supported. If support is added for
+ ** switching proxy locking mode off then it will need to fail if
+ ** the journal mode is WAL mode.
+ */
+ rc = SQLITE_ERROR /*SQLITE_PROTOCOL? SQLITE_MISUSE?*/;
+ }else{
+ /* turn off proxy locking - already off - NOOP */
+ rc = SQLITE_OK;
+ }
+ }else{
+ const char *proxyPath = (const char *)pArg;
+ if( isProxyStyle ){
+ proxyLockingContext *pCtx =
+ (proxyLockingContext*)pFile->lockingContext;
+ if( !strcmp(pArg, ":auto:")
+ || (pCtx->lockProxyPath &&
+ !strncmp(pCtx->lockProxyPath, proxyPath, MAXPATHLEN))
+ ){
+ rc = SQLITE_OK;
+ }else{
+ rc = switchLockProxyPath(pFile, proxyPath);
+ }
+ }else{
+ /* turn on proxy file locking */
+ rc = proxyTransformUnixFile(pFile, proxyPath);
+ }
+ }
+ return rc;
+ }
+ default: {
+ assert( 0 ); /* The call assures that only valid opcodes are sent */
+ }
+ }
+ /*NOTREACHED*/
+ return SQLITE_ERROR;
+}
+
+/*
+** Within this division (the proxying locking implementation) the procedures
+** above this point are all utilities. The lock-related methods of the
+** proxy-locking sqlite3_io_method object follow.
+*/
+
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int proxyCheckReservedLock(sqlite3_file *id, int *pResOut) {
+ unixFile *pFile = (unixFile*)id;
+ int rc = proxyTakeConch(pFile);
+ if( rc==SQLITE_OK ){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ if( pCtx->conchHeld>0 ){
+ unixFile *proxy = pCtx->lockProxy;
+ return proxy->pMethod->xCheckReservedLock((sqlite3_file*)proxy, pResOut);
+ }else{ /* conchHeld < 0 is lockless */
+ pResOut=0;
+ }
+ }
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int proxyLock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ int rc = proxyTakeConch(pFile);
+ if( rc==SQLITE_OK ){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ if( pCtx->conchHeld>0 ){
+ unixFile *proxy = pCtx->lockProxy;
+ rc = proxy->pMethod->xLock((sqlite3_file*)proxy, eFileLock);
+ pFile->eFileLock = proxy->eFileLock;
+ }else{
+ /* conchHeld < 0 is lockless */
+ }
+ }
+ return rc;
+}
+
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int proxyUnlock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ int rc = proxyTakeConch(pFile);
+ if( rc==SQLITE_OK ){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ if( pCtx->conchHeld>0 ){
+ unixFile *proxy = pCtx->lockProxy;
+ rc = proxy->pMethod->xUnlock((sqlite3_file*)proxy, eFileLock);
+ pFile->eFileLock = proxy->eFileLock;
+ }else{
+ /* conchHeld < 0 is lockless */
+ }
+ }
+ return rc;
+}
+
+/*
+** Close a file that uses proxy locks.
+*/
+static int proxyClose(sqlite3_file *id) {
+ if( ALWAYS(id) ){
+ unixFile *pFile = (unixFile*)id;
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ unixFile *lockProxy = pCtx->lockProxy;
+ unixFile *conchFile = pCtx->conchFile;
+ int rc = SQLITE_OK;
+
+ if( lockProxy ){
+ rc = lockProxy->pMethod->xUnlock((sqlite3_file*)lockProxy, NO_LOCK);
+ if( rc ) return rc;
+ rc = lockProxy->pMethod->xClose((sqlite3_file*)lockProxy);
+ if( rc ) return rc;
+ sqlite3_free(lockProxy);
+ pCtx->lockProxy = 0;
+ }
+ if( conchFile ){
+ if( pCtx->conchHeld ){
+ rc = proxyReleaseConch(pFile);
+ if( rc ) return rc;
+ }
+ rc = conchFile->pMethod->xClose((sqlite3_file*)conchFile);
+ if( rc ) return rc;
+ sqlite3_free(conchFile);
+ }
+ sqlite3DbFree(0, pCtx->lockProxyPath);
+ sqlite3_free(pCtx->conchFilePath);
+ sqlite3DbFree(0, pCtx->dbPath);
+ /* restore the original locking context and pMethod then close it */
+ pFile->lockingContext = pCtx->oldLockingContext;
+ pFile->pMethod = pCtx->pOldMethod;
+ sqlite3_free(pCtx);
+ return pFile->pMethod->xClose(id);
+ }
+ return SQLITE_OK;
+}
+
+
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+/*
+** The proxy locking style is intended for use with AFP filesystems.
+** And since AFP is only supported on MacOSX, the proxy locking is also
+** restricted to MacOSX.
+**
+**
+******************* End of the proxy lock implementation **********************
+******************************************************************************/
+
+/*
+** Initialize the operating system interface.
+**
+** This routine registers all VFS implementations for unix-like operating
+** systems. This routine, and the sqlite3_os_end() routine that follows,
+** should be the only routines in this file that are visible from other
+** files.
+**
+** This routine is called once during SQLite initialization and by a
+** single thread. The memory allocation and mutex subsystems have not
+** necessarily been initialized when this routine is called, and so they
+** should not be used.
+*/
+SQLITE_API int sqlite3_os_init(void){
+ /*
+ ** The following macro defines an initializer for an sqlite3_vfs object.
+ ** The name of the VFS is NAME. The pAppData is a pointer to a pointer
+ ** to the "finder" function. (pAppData is a pointer to a pointer because
+ ** silly C90 rules prohibit a void* from being cast to a function pointer
+ ** and so we have to go through the intermediate pointer to avoid problems
+ ** when compiling with -pedantic-errors on GCC.)
+ **
+ ** The FINDER parameter to this macro is the name of the pointer to the
+ ** finder-function. The finder-function returns a pointer to the
+ ** sqlite_io_methods object that implements the desired locking
+ ** behaviors. See the division above that contains the IOMETHODS
+ ** macro for addition information on finder-functions.
+ **
+ ** Most finders simply return a pointer to a fixed sqlite3_io_methods
+ ** object. But the "autolockIoFinder" available on MacOSX does a little
+ ** more than that; it looks at the filesystem type that hosts the
+ ** database file and tries to choose an locking method appropriate for
+ ** that filesystem time.
+ */
+ #define UNIXVFS(VFSNAME, FINDER) { \
+ 3, /* iVersion */ \
+ sizeof(unixFile), /* szOsFile */ \
+ MAX_PATHNAME, /* mxPathname */ \
+ 0, /* pNext */ \
+ VFSNAME, /* zName */ \
+ (void*)&FINDER, /* pAppData */ \
+ unixOpen, /* xOpen */ \
+ unixDelete, /* xDelete */ \
+ unixAccess, /* xAccess */ \
+ unixFullPathname, /* xFullPathname */ \
+ unixDlOpen, /* xDlOpen */ \
+ unixDlError, /* xDlError */ \
+ unixDlSym, /* xDlSym */ \
+ unixDlClose, /* xDlClose */ \
+ unixRandomness, /* xRandomness */ \
+ unixSleep, /* xSleep */ \
+ unixCurrentTime, /* xCurrentTime */ \
+ unixGetLastError, /* xGetLastError */ \
+ unixCurrentTimeInt64, /* xCurrentTimeInt64 */ \
+ unixSetSystemCall, /* xSetSystemCall */ \
+ unixGetSystemCall, /* xGetSystemCall */ \
+ unixNextSystemCall, /* xNextSystemCall */ \
+ }
+
+ /*
+ ** All default VFSes for unix are contained in the following array.
+ **
+ ** Note that the sqlite3_vfs.pNext field of the VFS object is modified
+ ** by the SQLite core when the VFS is registered. So the following
+ ** array cannot be const.
+ */
+ static sqlite3_vfs aVfs[] = {
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+ UNIXVFS("unix", autolockIoFinder ),
+#elif OS_VXWORKS
+ UNIXVFS("unix", vxworksIoFinder ),
+#else
+ UNIXVFS("unix", posixIoFinder ),
+#endif
+ UNIXVFS("unix-none", nolockIoFinder ),
+ UNIXVFS("unix-dotfile", dotlockIoFinder ),
+ UNIXVFS("unix-excl", posixIoFinder ),
+#if OS_VXWORKS
+ UNIXVFS("unix-namedsem", semIoFinder ),
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE || OS_VXWORKS
+ UNIXVFS("unix-posix", posixIoFinder ),
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE
+ UNIXVFS("unix-flock", flockIoFinder ),
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+ UNIXVFS("unix-afp", afpIoFinder ),
+ UNIXVFS("unix-nfs", nfsIoFinder ),
+ UNIXVFS("unix-proxy", proxyIoFinder ),
+#endif
+ };
+ unsigned int i; /* Loop counter */
+
+ /* Double-check that the aSyscall[] array has been constructed
+ ** correctly. See ticket [bb3a86e890c8e96ab] */
+ assert( ArraySize(aSyscall)==29 );
+
+ /* Register all VFSes defined in the aVfs[] array */
+ for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
+ sqlite3_vfs_register(&aVfs[i], i==0);
+ }
+ unixBigLock = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1);
+ return SQLITE_OK;
+}
+
+/*
+** Shutdown the operating system interface.
+**
+** Some operating systems might need to do some cleanup in this routine,
+** to release dynamically allocated objects. But not on unix.
+** This routine is a no-op for unix.
+*/
+SQLITE_API int sqlite3_os_end(void){
+ unixBigLock = 0;
+ return SQLITE_OK;
+}
+
+#endif /* SQLITE_OS_UNIX */
+
+/************** End of os_unix.c *********************************************/
+/************** Begin file os_win.c ******************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains code that is specific to Windows.
+*/
+/* #include "sqliteInt.h" */
+#if SQLITE_OS_WIN /* This file is used for Windows only */
+
+/*
+** Include code that is common to all os_*.c files
+*/
+/************** Include os_common.h in the middle of os_win.c ****************/
+/************** Begin file os_common.h ***************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains macros and a little bit of code that is common to
+** all of the platform-specific files (os_*.c) and is #included into those
+** files.
+**
+** This file should be #included by the os_*.c files only. It is not a
+** general purpose header file.
+*/
+#ifndef _OS_COMMON_H_
+#define _OS_COMMON_H_
+
+/*
+** At least two bugs have slipped in because we changed the MEMORY_DEBUG
+** macro to SQLITE_DEBUG and some older makefiles have not yet made the
+** switch. The following code should catch this problem at compile-time.
+*/
+#ifdef MEMORY_DEBUG
+# error "The MEMORY_DEBUG macro is obsolete. Use SQLITE_DEBUG instead."
+#endif
+
+/*
+** Macros for performance tracing. Normally turned off. Only works
+** on i486 hardware.
+*/
+#ifdef SQLITE_PERFORMANCE_TRACE
+
+/*
+** hwtime.h contains inline assembler code for implementing
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of os_common.h ****************/
+/************** Begin file hwtime.h ******************************************/
+/*
+** 2008 May 27
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
+*/
+#ifndef SQLITE_HWTIME_H
+#define SQLITE_HWTIME_H
+
+/*
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value. This can be used for high-res
+** profiling.
+*/
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+ (defined(i386) || defined(__i386__) || defined(_M_IX86))
+
+ #if defined(__GNUC__)
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned int lo, hi;
+ __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+ return (sqlite_uint64)hi << 32 | lo;
+ }
+
+ #elif defined(_MSC_VER)
+
+ __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+ __asm {
+ rdtsc
+ ret ; return value at EDX:EAX
+ }
+ }
+
+ #endif
+
+#elif (defined(__GNUC__) && defined(__x86_64__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long val;
+ __asm__ __volatile__ ("rdtsc" : "=A" (val));
+ return val;
+ }
+
+#elif (defined(__GNUC__) && defined(__ppc__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long long retval;
+ unsigned long junk;
+ __asm__ __volatile__ ("\n\
+ 1: mftbu %1\n\
+ mftb %L0\n\
+ mftbu %0\n\
+ cmpw %0,%1\n\
+ bne 1b"
+ : "=r" (retval), "=r" (junk));
+ return retval;
+ }
+
+#else
+
+ #error Need implementation of sqlite3Hwtime() for your platform.
+
+ /*
+ ** To compile without implementing sqlite3Hwtime() for your platform,
+ ** you can remove the above #error and use the following
+ ** stub function. You will lose timing support for many
+ ** of the debugging and testing utilities, but it should at
+ ** least compile and run.
+ */
+SQLITE_PRIVATE sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
+
+#endif
+
+#endif /* !defined(SQLITE_HWTIME_H) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in os_common.h ******************/
+
+static sqlite_uint64 g_start;
+static sqlite_uint64 g_elapsed;
+#define TIMER_START g_start=sqlite3Hwtime()
+#define TIMER_END g_elapsed=sqlite3Hwtime()-g_start
+#define TIMER_ELAPSED g_elapsed
+#else
+#define TIMER_START
+#define TIMER_END
+#define TIMER_ELAPSED ((sqlite_uint64)0)
+#endif
+
+/*
+** If we compile with the SQLITE_TEST macro set, then the following block
+** of code will give us the ability to simulate a disk I/O error. This
+** is used for testing the I/O recovery logic.
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API extern int sqlite3_io_error_hit;
+SQLITE_API extern int sqlite3_io_error_hardhit;
+SQLITE_API extern int sqlite3_io_error_pending;
+SQLITE_API extern int sqlite3_io_error_persist;
+SQLITE_API extern int sqlite3_io_error_benign;
+SQLITE_API extern int sqlite3_diskfull_pending;
+SQLITE_API extern int sqlite3_diskfull;
+#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
+#define SimulateIOError(CODE) \
+ if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
+ || sqlite3_io_error_pending-- == 1 ) \
+ { local_ioerr(); CODE; }
+static void local_ioerr(){
+ IOTRACE(("IOERR\n"));
+ sqlite3_io_error_hit++;
+ if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
+}
+#define SimulateDiskfullError(CODE) \
+ if( sqlite3_diskfull_pending ){ \
+ if( sqlite3_diskfull_pending == 1 ){ \
+ local_ioerr(); \
+ sqlite3_diskfull = 1; \
+ sqlite3_io_error_hit = 1; \
+ CODE; \
+ }else{ \
+ sqlite3_diskfull_pending--; \
+ } \
+ }
+#else
+#define SimulateIOErrorBenign(X)
+#define SimulateIOError(A)
+#define SimulateDiskfullError(A)
+#endif /* defined(SQLITE_TEST) */
+
+/*
+** When testing, keep a count of the number of open files.
+*/
+#if defined(SQLITE_TEST)
+SQLITE_API extern int sqlite3_open_file_count;
+#define OpenCounter(X) sqlite3_open_file_count+=(X)
+#else
+#define OpenCounter(X)
+#endif /* defined(SQLITE_TEST) */
+
+#endif /* !defined(_OS_COMMON_H_) */
+
+/************** End of os_common.h *******************************************/
+/************** Continuing where we left off in os_win.c *********************/
+
+/*
+** Include the header file for the Windows VFS.
+*/
+/* #include "os_win.h" */
+
+/*
+** Compiling and using WAL mode requires several APIs that are only
+** available in Windows platforms based on the NT kernel.
+*/
+#if !SQLITE_OS_WINNT && !defined(SQLITE_OMIT_WAL)
+# error "WAL mode requires support from the Windows NT kernel, compile\
+ with SQLITE_OMIT_WAL."
+#endif
+
+#if !SQLITE_OS_WINNT && SQLITE_MAX_MMAP_SIZE>0
+# error "Memory mapped files require support from the Windows NT kernel,\
+ compile with SQLITE_MAX_MMAP_SIZE=0."
+#endif
+
+/*
+** Are most of the Win32 ANSI APIs available (i.e. with certain exceptions
+** based on the sub-platform)?
+*/
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(SQLITE_WIN32_NO_ANSI)
+# define SQLITE_WIN32_HAS_ANSI
+#endif
+
+/*
+** Are most of the Win32 Unicode APIs available (i.e. with certain exceptions
+** based on the sub-platform)?
+*/
+#if (SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT) && \
+ !defined(SQLITE_WIN32_NO_WIDE)
+# define SQLITE_WIN32_HAS_WIDE
+#endif
+
+/*
+** Make sure at least one set of Win32 APIs is available.
+*/
+#if !defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_WIN32_HAS_WIDE)
+# error "At least one of SQLITE_WIN32_HAS_ANSI and SQLITE_WIN32_HAS_WIDE\
+ must be defined."
+#endif
+
+/*
+** Define the required Windows SDK version constants if they are not
+** already available.
+*/
+#ifndef NTDDI_WIN8
+# define NTDDI_WIN8 0x06020000
+#endif
+
+#ifndef NTDDI_WINBLUE
+# define NTDDI_WINBLUE 0x06030000
+#endif
+
+#ifndef NTDDI_WINTHRESHOLD
+# define NTDDI_WINTHRESHOLD 0x06040000
+#endif
+
+/*
+** Check to see if the GetVersionEx[AW] functions are deprecated on the
+** target system. GetVersionEx was first deprecated in Win8.1.
+*/
+#ifndef SQLITE_WIN32_GETVERSIONEX
+# if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WINBLUE
+# define SQLITE_WIN32_GETVERSIONEX 0 /* GetVersionEx() is deprecated */
+# else
+# define SQLITE_WIN32_GETVERSIONEX 1 /* GetVersionEx() is current */
+# endif
+#endif
+
+/*
+** Check to see if the CreateFileMappingA function is supported on the
+** target system. It is unavailable when using "mincore.lib" on Win10.
+** When compiling for Windows 10, always assume "mincore.lib" is in use.
+*/
+#ifndef SQLITE_WIN32_CREATEFILEMAPPINGA
+# if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WINTHRESHOLD
+# define SQLITE_WIN32_CREATEFILEMAPPINGA 0
+# else
+# define SQLITE_WIN32_CREATEFILEMAPPINGA 1
+# endif
+#endif
+
+/*
+** This constant should already be defined (in the "WinDef.h" SDK file).
+*/
+#ifndef MAX_PATH
+# define MAX_PATH (260)
+#endif
+
+/*
+** Maximum pathname length (in chars) for Win32. This should normally be
+** MAX_PATH.
+*/
+#ifndef SQLITE_WIN32_MAX_PATH_CHARS
+# define SQLITE_WIN32_MAX_PATH_CHARS (MAX_PATH)
+#endif
+
+/*
+** This constant should already be defined (in the "WinNT.h" SDK file).
+*/
+#ifndef UNICODE_STRING_MAX_CHARS
+# define UNICODE_STRING_MAX_CHARS (32767)
+#endif
+
+/*
+** Maximum pathname length (in chars) for WinNT. This should normally be
+** UNICODE_STRING_MAX_CHARS.
+*/
+#ifndef SQLITE_WINNT_MAX_PATH_CHARS
+# define SQLITE_WINNT_MAX_PATH_CHARS (UNICODE_STRING_MAX_CHARS)
+#endif
+
+/*
+** Maximum pathname length (in bytes) for Win32. The MAX_PATH macro is in
+** characters, so we allocate 4 bytes per character assuming worst-case of
+** 4-bytes-per-character for UTF8.
+*/
+#ifndef SQLITE_WIN32_MAX_PATH_BYTES
+# define SQLITE_WIN32_MAX_PATH_BYTES (SQLITE_WIN32_MAX_PATH_CHARS*4)
+#endif
+
+/*
+** Maximum pathname length (in bytes) for WinNT. This should normally be
+** UNICODE_STRING_MAX_CHARS * sizeof(WCHAR).
+*/
+#ifndef SQLITE_WINNT_MAX_PATH_BYTES
+# define SQLITE_WINNT_MAX_PATH_BYTES \
+ (sizeof(WCHAR) * SQLITE_WINNT_MAX_PATH_CHARS)
+#endif
+
+/*
+** Maximum error message length (in chars) for WinRT.
+*/
+#ifndef SQLITE_WIN32_MAX_ERRMSG_CHARS
+# define SQLITE_WIN32_MAX_ERRMSG_CHARS (1024)
+#endif
+
+/*
+** Returns non-zero if the character should be treated as a directory
+** separator.
+*/
+#ifndef winIsDirSep
+# define winIsDirSep(a) (((a) == '/') || ((a) == '\\'))
+#endif
+
+/*
+** This macro is used when a local variable is set to a value that is
+** [sometimes] not used by the code (e.g. via conditional compilation).
+*/
+#ifndef UNUSED_VARIABLE_VALUE
+# define UNUSED_VARIABLE_VALUE(x) (void)(x)
+#endif
+
+/*
+** Returns the character that should be used as the directory separator.
+*/
+#ifndef winGetDirSep
+# define winGetDirSep() '\\'
+#endif
+
+/*
+** Do we need to manually define the Win32 file mapping APIs for use with WAL
+** mode or memory mapped files (e.g. these APIs are available in the Windows
+** CE SDK; however, they are not present in the header file)?
+*/
+#if SQLITE_WIN32_FILEMAPPING_API && \
+ (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
+/*
+** Two of the file mapping APIs are different under WinRT. Figure out which
+** set we need.
+*/
+#if SQLITE_OS_WINRT
+WINBASEAPI HANDLE WINAPI CreateFileMappingFromApp(HANDLE, \
+ LPSECURITY_ATTRIBUTES, ULONG, ULONG64, LPCWSTR);
+
+WINBASEAPI LPVOID WINAPI MapViewOfFileFromApp(HANDLE, ULONG, ULONG64, SIZE_T);
+#else
+#if defined(SQLITE_WIN32_HAS_ANSI)
+WINBASEAPI HANDLE WINAPI CreateFileMappingA(HANDLE, LPSECURITY_ATTRIBUTES, \
+ DWORD, DWORD, DWORD, LPCSTR);
+#endif /* defined(SQLITE_WIN32_HAS_ANSI) */
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+WINBASEAPI HANDLE WINAPI CreateFileMappingW(HANDLE, LPSECURITY_ATTRIBUTES, \
+ DWORD, DWORD, DWORD, LPCWSTR);
+#endif /* defined(SQLITE_WIN32_HAS_WIDE) */
+
+WINBASEAPI LPVOID WINAPI MapViewOfFile(HANDLE, DWORD, DWORD, DWORD, SIZE_T);
+#endif /* SQLITE_OS_WINRT */
+
+/*
+** These file mapping APIs are common to both Win32 and WinRT.
+*/
+
+WINBASEAPI BOOL WINAPI FlushViewOfFile(LPCVOID, SIZE_T);
+WINBASEAPI BOOL WINAPI UnmapViewOfFile(LPCVOID);
+#endif /* SQLITE_WIN32_FILEMAPPING_API */
+
+/*
+** Some Microsoft compilers lack this definition.
+*/
+#ifndef INVALID_FILE_ATTRIBUTES
+# define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
+#endif
+
+#ifndef FILE_FLAG_MASK
+# define FILE_FLAG_MASK (0xFF3C0000)
+#endif
+
+#ifndef FILE_ATTRIBUTE_MASK
+# define FILE_ATTRIBUTE_MASK (0x0003FFF7)
+#endif
+
+#ifndef SQLITE_OMIT_WAL
+/* Forward references to structures used for WAL */
+typedef struct winShm winShm; /* A connection to shared-memory */
+typedef struct winShmNode winShmNode; /* A region of shared-memory */
+#endif
+
+/*
+** WinCE lacks native support for file locking so we have to fake it
+** with some code of our own.
+*/
+#if SQLITE_OS_WINCE
+typedef struct winceLock {
+ int nReaders; /* Number of reader locks obtained */
+ BOOL bPending; /* Indicates a pending lock has been obtained */
+ BOOL bReserved; /* Indicates a reserved lock has been obtained */
+ BOOL bExclusive; /* Indicates an exclusive lock has been obtained */
+} winceLock;
+#endif
+
+/*
+** The winFile structure is a subclass of sqlite3_file* specific to the win32
+** portability layer.
+*/
+typedef struct winFile winFile;
+struct winFile {
+ const sqlite3_io_methods *pMethod; /*** Must be first ***/
+ sqlite3_vfs *pVfs; /* The VFS used to open this file */
+ HANDLE h; /* Handle for accessing the file */
+ u8 locktype; /* Type of lock currently held on this file */
+ short sharedLockByte; /* Randomly chosen byte used as a shared lock */
+ u8 ctrlFlags; /* Flags. See WINFILE_* below */
+ DWORD lastErrno; /* The Windows errno from the last I/O error */
+#ifndef SQLITE_OMIT_WAL
+ winShm *pShm; /* Instance of shared memory on this file */
+#endif
+ const char *zPath; /* Full pathname of this file */
+ int szChunk; /* Chunk size configured by FCNTL_CHUNK_SIZE */
+#if SQLITE_OS_WINCE
+ LPWSTR zDeleteOnClose; /* Name of file to delete when closing */
+ HANDLE hMutex; /* Mutex used to control access to shared lock */
+ HANDLE hShared; /* Shared memory segment used for locking */
+ winceLock local; /* Locks obtained by this instance of winFile */
+ winceLock *shared; /* Global shared lock memory for the file */
+#endif
+#if SQLITE_MAX_MMAP_SIZE>0
+ int nFetchOut; /* Number of outstanding xFetch references */
+ HANDLE hMap; /* Handle for accessing memory mapping */
+ void *pMapRegion; /* Area memory mapped */
+ sqlite3_int64 mmapSize; /* Usable size of mapped region */
+ sqlite3_int64 mmapSizeActual; /* Actual size of mapped region */
+ sqlite3_int64 mmapSizeMax; /* Configured FCNTL_MMAP_SIZE value */
+#endif
+};
+
+/*
+** The winVfsAppData structure is used for the pAppData member for all of the
+** Win32 VFS variants.
+*/
+typedef struct winVfsAppData winVfsAppData;
+struct winVfsAppData {
+ const sqlite3_io_methods *pMethod; /* The file I/O methods to use. */
+ void *pAppData; /* The extra pAppData, if any. */
+ BOOL bNoLock; /* Non-zero if locking is disabled. */
+};
+
+/*
+** Allowed values for winFile.ctrlFlags
+*/
+#define WINFILE_RDONLY 0x02 /* Connection is read only */
+#define WINFILE_PERSIST_WAL 0x04 /* Persistent WAL mode */
+#define WINFILE_PSOW 0x10 /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
+
+/*
+ * The size of the buffer used by sqlite3_win32_write_debug().
+ */
+#ifndef SQLITE_WIN32_DBG_BUF_SIZE
+# define SQLITE_WIN32_DBG_BUF_SIZE ((int)(4096-sizeof(DWORD)))
+#endif
+
+/*
+ * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
+ * various Win32 API heap functions instead of our own.
+ */
+#ifdef SQLITE_WIN32_MALLOC
+
+/*
+ * If this is non-zero, an isolated heap will be created by the native Win32
+ * allocator subsystem; otherwise, the default process heap will be used. This
+ * setting has no effect when compiling for WinRT. By default, this is enabled
+ * and an isolated heap will be created to store all allocated data.
+ *
+ ******************************************************************************
+ * WARNING: It is important to note that when this setting is non-zero and the
+ * winMemShutdown function is called (e.g. by the sqlite3_shutdown
+ * function), all data that was allocated using the isolated heap will
+ * be freed immediately and any attempt to access any of that freed
+ * data will almost certainly result in an immediate access violation.
+ ******************************************************************************
+ */
+#ifndef SQLITE_WIN32_HEAP_CREATE
+# define SQLITE_WIN32_HEAP_CREATE (TRUE)
+#endif
+
+/*
+ * This is the maximum possible initial size of the Win32-specific heap, in
+ * bytes.
+ */
+#ifndef SQLITE_WIN32_HEAP_MAX_INIT_SIZE
+# define SQLITE_WIN32_HEAP_MAX_INIT_SIZE (4294967295U)
+#endif
+
+/*
+ * This is the extra space for the initial size of the Win32-specific heap,
+ * in bytes. This value may be zero.
+ */
+#ifndef SQLITE_WIN32_HEAP_INIT_EXTRA
+# define SQLITE_WIN32_HEAP_INIT_EXTRA (4194304)
+#endif
+
+/*
+ * Calculate the maximum legal cache size, in pages, based on the maximum
+ * possible initial heap size and the default page size, setting aside the
+ * needed extra space.
+ */
+#ifndef SQLITE_WIN32_MAX_CACHE_SIZE
+# define SQLITE_WIN32_MAX_CACHE_SIZE (((SQLITE_WIN32_HEAP_MAX_INIT_SIZE) - \
+ (SQLITE_WIN32_HEAP_INIT_EXTRA)) / \
+ (SQLITE_DEFAULT_PAGE_SIZE))
+#endif
+
+/*
+ * This is cache size used in the calculation of the initial size of the
+ * Win32-specific heap. It cannot be negative.
+ */
+#ifndef SQLITE_WIN32_CACHE_SIZE
+# if SQLITE_DEFAULT_CACHE_SIZE>=0
+# define SQLITE_WIN32_CACHE_SIZE (SQLITE_DEFAULT_CACHE_SIZE)
+# else
+# define SQLITE_WIN32_CACHE_SIZE (-(SQLITE_DEFAULT_CACHE_SIZE))
+# endif
+#endif
+
+/*
+ * Make sure that the calculated cache size, in pages, cannot cause the
+ * initial size of the Win32-specific heap to exceed the maximum amount
+ * of memory that can be specified in the call to HeapCreate.
+ */
+#if SQLITE_WIN32_CACHE_SIZE>SQLITE_WIN32_MAX_CACHE_SIZE
+# undef SQLITE_WIN32_CACHE_SIZE
+# define SQLITE_WIN32_CACHE_SIZE (2000)
+#endif
+
+/*
+ * The initial size of the Win32-specific heap. This value may be zero.
+ */
+#ifndef SQLITE_WIN32_HEAP_INIT_SIZE
+# define SQLITE_WIN32_HEAP_INIT_SIZE ((SQLITE_WIN32_CACHE_SIZE) * \
+ (SQLITE_DEFAULT_PAGE_SIZE) + \
+ (SQLITE_WIN32_HEAP_INIT_EXTRA))
+#endif
+
+/*
+ * The maximum size of the Win32-specific heap. This value may be zero.
+ */
+#ifndef SQLITE_WIN32_HEAP_MAX_SIZE
+# define SQLITE_WIN32_HEAP_MAX_SIZE (0)
+#endif
+
+/*
+ * The extra flags to use in calls to the Win32 heap APIs. This value may be
+ * zero for the default behavior.
+ */
+#ifndef SQLITE_WIN32_HEAP_FLAGS
+# define SQLITE_WIN32_HEAP_FLAGS (0)
+#endif
+
+
+/*
+** The winMemData structure stores information required by the Win32-specific
+** sqlite3_mem_methods implementation.
+*/
+typedef struct winMemData winMemData;
+struct winMemData {
+#ifndef NDEBUG
+ u32 magic1; /* Magic number to detect structure corruption. */
+#endif
+ HANDLE hHeap; /* The handle to our heap. */
+ BOOL bOwned; /* Do we own the heap (i.e. destroy it on shutdown)? */
+#ifndef NDEBUG
+ u32 magic2; /* Magic number to detect structure corruption. */
+#endif
+};
+
+#ifndef NDEBUG
+#define WINMEM_MAGIC1 0x42b2830b
+#define WINMEM_MAGIC2 0xbd4d7cf4
+#endif
+
+static struct winMemData win_mem_data = {
+#ifndef NDEBUG
+ WINMEM_MAGIC1,
+#endif
+ NULL, FALSE
+#ifndef NDEBUG
+ ,WINMEM_MAGIC2
+#endif
+};
+
+#ifndef NDEBUG
+#define winMemAssertMagic1() assert( win_mem_data.magic1==WINMEM_MAGIC1 )
+#define winMemAssertMagic2() assert( win_mem_data.magic2==WINMEM_MAGIC2 )
+#define winMemAssertMagic() winMemAssertMagic1(); winMemAssertMagic2();
+#else
+#define winMemAssertMagic()
+#endif
+
+#define winMemGetDataPtr() &win_mem_data
+#define winMemGetHeap() win_mem_data.hHeap
+#define winMemGetOwned() win_mem_data.bOwned
+
+static void *winMemMalloc(int nBytes);
+static void winMemFree(void *pPrior);
+static void *winMemRealloc(void *pPrior, int nBytes);
+static int winMemSize(void *p);
+static int winMemRoundup(int n);
+static int winMemInit(void *pAppData);
+static void winMemShutdown(void *pAppData);
+
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetWin32(void);
+#endif /* SQLITE_WIN32_MALLOC */
+
+/*
+** The following variable is (normally) set once and never changes
+** thereafter. It records whether the operating system is Win9x
+** or WinNT.
+**
+** 0: Operating system unknown.
+** 1: Operating system is Win9x.
+** 2: Operating system is WinNT.
+**
+** In order to facilitate testing on a WinNT system, the test fixture
+** can manually set this value to 1 to emulate Win98 behavior.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API LONG SQLITE_WIN32_VOLATILE sqlite3_os_type = 0;
+#else
+static LONG SQLITE_WIN32_VOLATILE sqlite3_os_type = 0;
+#endif
+
+#ifndef SYSCALL
+# define SYSCALL sqlite3_syscall_ptr
+#endif
+
+/*
+** This function is not available on Windows CE or WinRT.
+ */
+
+#if SQLITE_OS_WINCE || SQLITE_OS_WINRT
+# define osAreFileApisANSI() 1
+#endif
+
+/*
+** Many system calls are accessed through pointer-to-functions so that
+** they may be overridden at runtime to facilitate fault injection during
+** testing and sandboxing. The following array holds the names and pointers
+** to all overrideable system calls.
+*/
+static struct win_syscall {
+ const char *zName; /* Name of the system call */
+ sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
+ sqlite3_syscall_ptr pDefault; /* Default value */
+} aSyscall[] = {
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+ { "AreFileApisANSI", (SYSCALL)AreFileApisANSI, 0 },
+#else
+ { "AreFileApisANSI", (SYSCALL)0, 0 },
+#endif
+
+#ifndef osAreFileApisANSI
+#define osAreFileApisANSI ((BOOL(WINAPI*)(VOID))aSyscall[0].pCurrent)
+#endif
+
+#if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
+ { "CharLowerW", (SYSCALL)CharLowerW, 0 },
+#else
+ { "CharLowerW", (SYSCALL)0, 0 },
+#endif
+
+#define osCharLowerW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[1].pCurrent)
+
+#if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
+ { "CharUpperW", (SYSCALL)CharUpperW, 0 },
+#else
+ { "CharUpperW", (SYSCALL)0, 0 },
+#endif
+
+#define osCharUpperW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[2].pCurrent)
+
+ { "CloseHandle", (SYSCALL)CloseHandle, 0 },
+
+#define osCloseHandle ((BOOL(WINAPI*)(HANDLE))aSyscall[3].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "CreateFileA", (SYSCALL)CreateFileA, 0 },
+#else
+ { "CreateFileA", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileA ((HANDLE(WINAPI*)(LPCSTR,DWORD,DWORD, \
+ LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[4].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "CreateFileW", (SYSCALL)CreateFileW, 0 },
+#else
+ { "CreateFileW", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
+ LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_ANSI) && \
+ (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0) && \
+ SQLITE_WIN32_CREATEFILEMAPPINGA
+ { "CreateFileMappingA", (SYSCALL)CreateFileMappingA, 0 },
+#else
+ { "CreateFileMappingA", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileMappingA ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
+ DWORD,DWORD,DWORD,LPCSTR))aSyscall[6].pCurrent)
+
+#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
+ (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0))
+ { "CreateFileMappingW", (SYSCALL)CreateFileMappingW, 0 },
+#else
+ { "CreateFileMappingW", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
+ DWORD,DWORD,DWORD,LPCWSTR))aSyscall[7].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "CreateMutexW", (SYSCALL)CreateMutexW, 0 },
+#else
+ { "CreateMutexW", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateMutexW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,BOOL, \
+ LPCWSTR))aSyscall[8].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "DeleteFileA", (SYSCALL)DeleteFileA, 0 },
+#else
+ { "DeleteFileA", (SYSCALL)0, 0 },
+#endif
+
+#define osDeleteFileA ((BOOL(WINAPI*)(LPCSTR))aSyscall[9].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ { "DeleteFileW", (SYSCALL)DeleteFileW, 0 },
+#else
+ { "DeleteFileW", (SYSCALL)0, 0 },
+#endif
+
+#define osDeleteFileW ((BOOL(WINAPI*)(LPCWSTR))aSyscall[10].pCurrent)
+
+#if SQLITE_OS_WINCE
+ { "FileTimeToLocalFileTime", (SYSCALL)FileTimeToLocalFileTime, 0 },
+#else
+ { "FileTimeToLocalFileTime", (SYSCALL)0, 0 },
+#endif
+
+#define osFileTimeToLocalFileTime ((BOOL(WINAPI*)(CONST FILETIME*, \
+ LPFILETIME))aSyscall[11].pCurrent)
+
+#if SQLITE_OS_WINCE
+ { "FileTimeToSystemTime", (SYSCALL)FileTimeToSystemTime, 0 },
+#else
+ { "FileTimeToSystemTime", (SYSCALL)0, 0 },
+#endif
+
+#define osFileTimeToSystemTime ((BOOL(WINAPI*)(CONST FILETIME*, \
+ LPSYSTEMTIME))aSyscall[12].pCurrent)
+
+ { "FlushFileBuffers", (SYSCALL)FlushFileBuffers, 0 },
+
+#define osFlushFileBuffers ((BOOL(WINAPI*)(HANDLE))aSyscall[13].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "FormatMessageA", (SYSCALL)FormatMessageA, 0 },
+#else
+ { "FormatMessageA", (SYSCALL)0, 0 },
+#endif
+
+#define osFormatMessageA ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPSTR, \
+ DWORD,va_list*))aSyscall[14].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ { "FormatMessageW", (SYSCALL)FormatMessageW, 0 },
+#else
+ { "FormatMessageW", (SYSCALL)0, 0 },
+#endif
+
+#define osFormatMessageW ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPWSTR, \
+ DWORD,va_list*))aSyscall[15].pCurrent)
+
+#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
+ { "FreeLibrary", (SYSCALL)FreeLibrary, 0 },
+#else
+ { "FreeLibrary", (SYSCALL)0, 0 },
+#endif
+
+#define osFreeLibrary ((BOOL(WINAPI*)(HMODULE))aSyscall[16].pCurrent)
+
+ { "GetCurrentProcessId", (SYSCALL)GetCurrentProcessId, 0 },
+
+#define osGetCurrentProcessId ((DWORD(WINAPI*)(VOID))aSyscall[17].pCurrent)
+
+#if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
+ { "GetDiskFreeSpaceA", (SYSCALL)GetDiskFreeSpaceA, 0 },
+#else
+ { "GetDiskFreeSpaceA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetDiskFreeSpaceA ((BOOL(WINAPI*)(LPCSTR,LPDWORD,LPDWORD,LPDWORD, \
+ LPDWORD))aSyscall[18].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetDiskFreeSpaceW", (SYSCALL)GetDiskFreeSpaceW, 0 },
+#else
+ { "GetDiskFreeSpaceW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetDiskFreeSpaceW ((BOOL(WINAPI*)(LPCWSTR,LPDWORD,LPDWORD,LPDWORD, \
+ LPDWORD))aSyscall[19].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "GetFileAttributesA", (SYSCALL)GetFileAttributesA, 0 },
+#else
+ { "GetFileAttributesA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileAttributesA ((DWORD(WINAPI*)(LPCSTR))aSyscall[20].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetFileAttributesW", (SYSCALL)GetFileAttributesW, 0 },
+#else
+ { "GetFileAttributesW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileAttributesW ((DWORD(WINAPI*)(LPCWSTR))aSyscall[21].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetFileAttributesExW", (SYSCALL)GetFileAttributesExW, 0 },
+#else
+ { "GetFileAttributesExW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileAttributesExW ((BOOL(WINAPI*)(LPCWSTR,GET_FILEEX_INFO_LEVELS, \
+ LPVOID))aSyscall[22].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "GetFileSize", (SYSCALL)GetFileSize, 0 },
+#else
+ { "GetFileSize", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileSize ((DWORD(WINAPI*)(HANDLE,LPDWORD))aSyscall[23].pCurrent)
+
+#if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
+ { "GetFullPathNameA", (SYSCALL)GetFullPathNameA, 0 },
+#else
+ { "GetFullPathNameA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFullPathNameA ((DWORD(WINAPI*)(LPCSTR,DWORD,LPSTR, \
+ LPSTR*))aSyscall[24].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetFullPathNameW", (SYSCALL)GetFullPathNameW, 0 },
+#else
+ { "GetFullPathNameW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFullPathNameW ((DWORD(WINAPI*)(LPCWSTR,DWORD,LPWSTR, \
+ LPWSTR*))aSyscall[25].pCurrent)
+
+ { "GetLastError", (SYSCALL)GetLastError, 0 },
+
+#define osGetLastError ((DWORD(WINAPI*)(VOID))aSyscall[26].pCurrent)
+
+#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
+#if SQLITE_OS_WINCE
+ /* The GetProcAddressA() routine is only available on Windows CE. */
+ { "GetProcAddressA", (SYSCALL)GetProcAddressA, 0 },
+#else
+ /* All other Windows platforms expect GetProcAddress() to take
+ ** an ANSI string regardless of the _UNICODE setting */
+ { "GetProcAddressA", (SYSCALL)GetProcAddress, 0 },
+#endif
+#else
+ { "GetProcAddressA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetProcAddressA ((FARPROC(WINAPI*)(HMODULE, \
+ LPCSTR))aSyscall[27].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "GetSystemInfo", (SYSCALL)GetSystemInfo, 0 },
+#else
+ { "GetSystemInfo", (SYSCALL)0, 0 },
+#endif
+
+#define osGetSystemInfo ((VOID(WINAPI*)(LPSYSTEM_INFO))aSyscall[28].pCurrent)
+
+ { "GetSystemTime", (SYSCALL)GetSystemTime, 0 },
+
+#define osGetSystemTime ((VOID(WINAPI*)(LPSYSTEMTIME))aSyscall[29].pCurrent)
+
+#if !SQLITE_OS_WINCE
+ { "GetSystemTimeAsFileTime", (SYSCALL)GetSystemTimeAsFileTime, 0 },
+#else
+ { "GetSystemTimeAsFileTime", (SYSCALL)0, 0 },
+#endif
+
+#define osGetSystemTimeAsFileTime ((VOID(WINAPI*)( \
+ LPFILETIME))aSyscall[30].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "GetTempPathA", (SYSCALL)GetTempPathA, 0 },
+#else
+ { "GetTempPathA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetTempPathA ((DWORD(WINAPI*)(DWORD,LPSTR))aSyscall[31].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetTempPathW", (SYSCALL)GetTempPathW, 0 },
+#else
+ { "GetTempPathW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetTempPathW ((DWORD(WINAPI*)(DWORD,LPWSTR))aSyscall[32].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "GetTickCount", (SYSCALL)GetTickCount, 0 },
+#else
+ { "GetTickCount", (SYSCALL)0, 0 },
+#endif
+
+#define osGetTickCount ((DWORD(WINAPI*)(VOID))aSyscall[33].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_GETVERSIONEX
+ { "GetVersionExA", (SYSCALL)GetVersionExA, 0 },
+#else
+ { "GetVersionExA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetVersionExA ((BOOL(WINAPI*)( \
+ LPOSVERSIONINFOA))aSyscall[34].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
+ SQLITE_WIN32_GETVERSIONEX
+ { "GetVersionExW", (SYSCALL)GetVersionExW, 0 },
+#else
+ { "GetVersionExW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetVersionExW ((BOOL(WINAPI*)( \
+ LPOSVERSIONINFOW))aSyscall[35].pCurrent)
+
+ { "HeapAlloc", (SYSCALL)HeapAlloc, 0 },
+
+#define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
+ SIZE_T))aSyscall[36].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "HeapCreate", (SYSCALL)HeapCreate, 0 },
+#else
+ { "HeapCreate", (SYSCALL)0, 0 },
+#endif
+
+#define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
+ SIZE_T))aSyscall[37].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "HeapDestroy", (SYSCALL)HeapDestroy, 0 },
+#else
+ { "HeapDestroy", (SYSCALL)0, 0 },
+#endif
+
+#define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[38].pCurrent)
+
+ { "HeapFree", (SYSCALL)HeapFree, 0 },
+
+#define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[39].pCurrent)
+
+ { "HeapReAlloc", (SYSCALL)HeapReAlloc, 0 },
+
+#define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
+ SIZE_T))aSyscall[40].pCurrent)
+
+ { "HeapSize", (SYSCALL)HeapSize, 0 },
+
+#define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
+ LPCVOID))aSyscall[41].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "HeapValidate", (SYSCALL)HeapValidate, 0 },
+#else
+ { "HeapValidate", (SYSCALL)0, 0 },
+#endif
+
+#define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
+ LPCVOID))aSyscall[42].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+ { "HeapCompact", (SYSCALL)HeapCompact, 0 },
+#else
+ { "HeapCompact", (SYSCALL)0, 0 },
+#endif
+
+#define osHeapCompact ((UINT(WINAPI*)(HANDLE,DWORD))aSyscall[43].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
+ { "LoadLibraryA", (SYSCALL)LoadLibraryA, 0 },
+#else
+ { "LoadLibraryA", (SYSCALL)0, 0 },
+#endif
+
+#define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[44].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
+ !defined(SQLITE_OMIT_LOAD_EXTENSION)
+ { "LoadLibraryW", (SYSCALL)LoadLibraryW, 0 },
+#else
+ { "LoadLibraryW", (SYSCALL)0, 0 },
+#endif
+
+#define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[45].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "LocalFree", (SYSCALL)LocalFree, 0 },
+#else
+ { "LocalFree", (SYSCALL)0, 0 },
+#endif
+
+#define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[46].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+ { "LockFile", (SYSCALL)LockFile, 0 },
+#else
+ { "LockFile", (SYSCALL)0, 0 },
+#endif
+
+#ifndef osLockFile
+#define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
+ DWORD))aSyscall[47].pCurrent)
+#endif
+
+#if !SQLITE_OS_WINCE
+ { "LockFileEx", (SYSCALL)LockFileEx, 0 },
+#else
+ { "LockFileEx", (SYSCALL)0, 0 },
+#endif
+
+#ifndef osLockFileEx
+#define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
+ LPOVERLAPPED))aSyscall[48].pCurrent)
+#endif
+
+#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && \
+ (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0))
+ { "MapViewOfFile", (SYSCALL)MapViewOfFile, 0 },
+#else
+ { "MapViewOfFile", (SYSCALL)0, 0 },
+#endif
+
+#define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
+ SIZE_T))aSyscall[49].pCurrent)
+
+ { "MultiByteToWideChar", (SYSCALL)MultiByteToWideChar, 0 },
+
+#define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
+ int))aSyscall[50].pCurrent)
+
+ { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },
+
+#define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
+ LARGE_INTEGER*))aSyscall[51].pCurrent)
+
+ { "ReadFile", (SYSCALL)ReadFile, 0 },
+
+#define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
+ LPOVERLAPPED))aSyscall[52].pCurrent)
+
+ { "SetEndOfFile", (SYSCALL)SetEndOfFile, 0 },
+
+#define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[53].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "SetFilePointer", (SYSCALL)SetFilePointer, 0 },
+#else
+ { "SetFilePointer", (SYSCALL)0, 0 },
+#endif
+
+#define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
+ DWORD))aSyscall[54].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "Sleep", (SYSCALL)Sleep, 0 },
+#else
+ { "Sleep", (SYSCALL)0, 0 },
+#endif
+
+#define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[55].pCurrent)
+
+ { "SystemTimeToFileTime", (SYSCALL)SystemTimeToFileTime, 0 },
+
+#define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
+ LPFILETIME))aSyscall[56].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+ { "UnlockFile", (SYSCALL)UnlockFile, 0 },
+#else
+ { "UnlockFile", (SYSCALL)0, 0 },
+#endif
+
+#ifndef osUnlockFile
+#define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
+ DWORD))aSyscall[57].pCurrent)
+#endif
+
+#if !SQLITE_OS_WINCE
+ { "UnlockFileEx", (SYSCALL)UnlockFileEx, 0 },
+#else
+ { "UnlockFileEx", (SYSCALL)0, 0 },
+#endif
+
+#define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
+ LPOVERLAPPED))aSyscall[58].pCurrent)
+
+#if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
+ { "UnmapViewOfFile", (SYSCALL)UnmapViewOfFile, 0 },
+#else
+ { "UnmapViewOfFile", (SYSCALL)0, 0 },
+#endif
+
+#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[59].pCurrent)
+
+ { "WideCharToMultiByte", (SYSCALL)WideCharToMultiByte, 0 },
+
+#define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
+ LPCSTR,LPBOOL))aSyscall[60].pCurrent)
+
+ { "WriteFile", (SYSCALL)WriteFile, 0 },
+
+#define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
+ LPOVERLAPPED))aSyscall[61].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "CreateEventExW", (SYSCALL)CreateEventExW, 0 },
+#else
+ { "CreateEventExW", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
+ DWORD,DWORD))aSyscall[62].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "WaitForSingleObject", (SYSCALL)WaitForSingleObject, 0 },
+#else
+ { "WaitForSingleObject", (SYSCALL)0, 0 },
+#endif
+
+#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
+ DWORD))aSyscall[63].pCurrent)
+
+#if !SQLITE_OS_WINCE
+ { "WaitForSingleObjectEx", (SYSCALL)WaitForSingleObjectEx, 0 },
+#else
+ { "WaitForSingleObjectEx", (SYSCALL)0, 0 },
+#endif
+
+#define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
+ BOOL))aSyscall[64].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "SetFilePointerEx", (SYSCALL)SetFilePointerEx, 0 },
+#else
+ { "SetFilePointerEx", (SYSCALL)0, 0 },
+#endif
+
+#define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
+ PLARGE_INTEGER,DWORD))aSyscall[65].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
+#else
+ { "GetFileInformationByHandleEx", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
+ FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[66].pCurrent)
+
+#if SQLITE_OS_WINRT && (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
+ { "MapViewOfFileFromApp", (SYSCALL)MapViewOfFileFromApp, 0 },
+#else
+ { "MapViewOfFileFromApp", (SYSCALL)0, 0 },
+#endif
+
+#define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
+ SIZE_T))aSyscall[67].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "CreateFile2", (SYSCALL)CreateFile2, 0 },
+#else
+ { "CreateFile2", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
+ LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[68].pCurrent)
+
+#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
+ { "LoadPackagedLibrary", (SYSCALL)LoadPackagedLibrary, 0 },
+#else
+ { "LoadPackagedLibrary", (SYSCALL)0, 0 },
+#endif
+
+#define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
+ DWORD))aSyscall[69].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "GetTickCount64", (SYSCALL)GetTickCount64, 0 },
+#else
+ { "GetTickCount64", (SYSCALL)0, 0 },
+#endif
+
+#define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[70].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "GetNativeSystemInfo", (SYSCALL)GetNativeSystemInfo, 0 },
+#else
+ { "GetNativeSystemInfo", (SYSCALL)0, 0 },
+#endif
+
+#define osGetNativeSystemInfo ((VOID(WINAPI*)( \
+ LPSYSTEM_INFO))aSyscall[71].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "OutputDebugStringA", (SYSCALL)OutputDebugStringA, 0 },
+#else
+ { "OutputDebugStringA", (SYSCALL)0, 0 },
+#endif
+
+#define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[72].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ { "OutputDebugStringW", (SYSCALL)OutputDebugStringW, 0 },
+#else
+ { "OutputDebugStringW", (SYSCALL)0, 0 },
+#endif
+
+#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[73].pCurrent)
+
+ { "GetProcessHeap", (SYSCALL)GetProcessHeap, 0 },
+
+#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[74].pCurrent)
+
+#if SQLITE_OS_WINRT && (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
+ { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
+#else
+ { "CreateFileMappingFromApp", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
+ LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[75].pCurrent)
+
+/*
+** NOTE: On some sub-platforms, the InterlockedCompareExchange "function"
+** is really just a macro that uses a compiler intrinsic (e.g. x64).
+** So do not try to make this is into a redefinable interface.
+*/
+#if defined(InterlockedCompareExchange)
+ { "InterlockedCompareExchange", (SYSCALL)0, 0 },
+
+#define osInterlockedCompareExchange InterlockedCompareExchange
+#else
+ { "InterlockedCompareExchange", (SYSCALL)InterlockedCompareExchange, 0 },
+
+#define osInterlockedCompareExchange ((LONG(WINAPI*)(LONG \
+ SQLITE_WIN32_VOLATILE*, LONG,LONG))aSyscall[76].pCurrent)
+#endif /* defined(InterlockedCompareExchange) */
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
+ { "UuidCreate", (SYSCALL)UuidCreate, 0 },
+#else
+ { "UuidCreate", (SYSCALL)0, 0 },
+#endif
+
+#define osUuidCreate ((RPC_STATUS(RPC_ENTRY*)(UUID*))aSyscall[77].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
+ { "UuidCreateSequential", (SYSCALL)UuidCreateSequential, 0 },
+#else
+ { "UuidCreateSequential", (SYSCALL)0, 0 },
+#endif
+
+#define osUuidCreateSequential \
+ ((RPC_STATUS(RPC_ENTRY*)(UUID*))aSyscall[78].pCurrent)
+
+#if !defined(SQLITE_NO_SYNC) && SQLITE_MAX_MMAP_SIZE>0
+ { "FlushViewOfFile", (SYSCALL)FlushViewOfFile, 0 },
+#else
+ { "FlushViewOfFile", (SYSCALL)0, 0 },
+#endif
+
+#define osFlushViewOfFile \
+ ((BOOL(WINAPI*)(LPCVOID,SIZE_T))aSyscall[79].pCurrent)
+
+}; /* End of the overrideable system calls */
+
+/*
+** This is the xSetSystemCall() method of sqlite3_vfs for all of the
+** "win32" VFSes. Return SQLITE_OK opon successfully updating the
+** system call pointer, or SQLITE_NOTFOUND if there is no configurable
+** system call named zName.
+*/
+static int winSetSystemCall(
+ sqlite3_vfs *pNotUsed, /* The VFS pointer. Not used */
+ const char *zName, /* Name of system call to override */
+ sqlite3_syscall_ptr pNewFunc /* Pointer to new system call value */
+){
+ unsigned int i;
+ int rc = SQLITE_NOTFOUND;
+
+ UNUSED_PARAMETER(pNotUsed);
+ if( zName==0 ){
+ /* If no zName is given, restore all system calls to their default
+ ** settings and return NULL
+ */
+ rc = SQLITE_OK;
+ for(i=0; i0 ){
+ memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
+ memcpy(zDbgBuf, zBuf, nMin);
+ osOutputDebugStringA(zDbgBuf);
+ }else{
+ osOutputDebugStringA(zBuf);
+ }
+#elif defined(SQLITE_WIN32_HAS_WIDE)
+ memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
+ if ( osMultiByteToWideChar(
+ osAreFileApisANSI() ? CP_ACP : CP_OEMCP, 0, zBuf,
+ nMin, (LPWSTR)zDbgBuf, SQLITE_WIN32_DBG_BUF_SIZE/sizeof(WCHAR))<=0 ){
+ return;
+ }
+ osOutputDebugStringW((LPCWSTR)zDbgBuf);
+#else
+ if( nMin>0 ){
+ memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
+ memcpy(zDbgBuf, zBuf, nMin);
+ fprintf(stderr, "%s", zDbgBuf);
+ }else{
+ fprintf(stderr, "%s", zBuf);
+ }
+#endif
+}
+
+/*
+** The following routine suspends the current thread for at least ms
+** milliseconds. This is equivalent to the Win32 Sleep() interface.
+*/
+#if SQLITE_OS_WINRT
+static HANDLE sleepObj = NULL;
+#endif
+
+SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds){
+#if SQLITE_OS_WINRT
+ if ( sleepObj==NULL ){
+ sleepObj = osCreateEventExW(NULL, NULL, CREATE_EVENT_MANUAL_RESET,
+ SYNCHRONIZE);
+ }
+ assert( sleepObj!=NULL );
+ osWaitForSingleObjectEx(sleepObj, milliseconds, FALSE);
+#else
+ osSleep(milliseconds);
+#endif
+}
+
+#if SQLITE_MAX_WORKER_THREADS>0 && !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
+ SQLITE_THREADSAFE>0
+SQLITE_PRIVATE DWORD sqlite3Win32Wait(HANDLE hObject){
+ DWORD rc;
+ while( (rc = osWaitForSingleObjectEx(hObject, INFINITE,
+ TRUE))==WAIT_IO_COMPLETION ){}
+ return rc;
+}
+#endif
+
+/*
+** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
+** or WinCE. Return false (zero) for Win95, Win98, or WinME.
+**
+** Here is an interesting observation: Win95, Win98, and WinME lack
+** the LockFileEx() API. But we can still statically link against that
+** API as long as we don't call it when running Win95/98/ME. A call to
+** this routine is used to determine if the host is Win95/98/ME or
+** WinNT/2K/XP so that we will know whether or not we can safely call
+** the LockFileEx() API.
+*/
+
+#if !SQLITE_WIN32_GETVERSIONEX
+# define osIsNT() (1)
+#elif SQLITE_OS_WINCE || SQLITE_OS_WINRT || !defined(SQLITE_WIN32_HAS_ANSI)
+# define osIsNT() (1)
+#elif !defined(SQLITE_WIN32_HAS_WIDE)
+# define osIsNT() (0)
+#else
+# define osIsNT() ((sqlite3_os_type==2) || sqlite3_win32_is_nt())
+#endif
+
+/*
+** This function determines if the machine is running a version of Windows
+** based on the NT kernel.
+*/
+SQLITE_API int sqlite3_win32_is_nt(void){
+#if SQLITE_OS_WINRT
+ /*
+ ** NOTE: The WinRT sub-platform is always assumed to be based on the NT
+ ** kernel.
+ */
+ return 1;
+#elif SQLITE_WIN32_GETVERSIONEX
+ if( osInterlockedCompareExchange(&sqlite3_os_type, 0, 0)==0 ){
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ OSVERSIONINFOA sInfo;
+ sInfo.dwOSVersionInfoSize = sizeof(sInfo);
+ osGetVersionExA(&sInfo);
+ osInterlockedCompareExchange(&sqlite3_os_type,
+ (sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) ? 2 : 1, 0);
+#elif defined(SQLITE_WIN32_HAS_WIDE)
+ OSVERSIONINFOW sInfo;
+ sInfo.dwOSVersionInfoSize = sizeof(sInfo);
+ osGetVersionExW(&sInfo);
+ osInterlockedCompareExchange(&sqlite3_os_type,
+ (sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) ? 2 : 1, 0);
+#endif
+ }
+ return osInterlockedCompareExchange(&sqlite3_os_type, 2, 2)==2;
+#elif SQLITE_TEST
+ return osInterlockedCompareExchange(&sqlite3_os_type, 2, 2)==2;
+#else
+ /*
+ ** NOTE: All sub-platforms where the GetVersionEx[AW] functions are
+ ** deprecated are always assumed to be based on the NT kernel.
+ */
+ return 1;
+#endif
+}
+
+#ifdef SQLITE_WIN32_MALLOC
+/*
+** Allocate nBytes of memory.
+*/
+static void *winMemMalloc(int nBytes){
+ HANDLE hHeap;
+ void *p;
+
+ winMemAssertMagic();
+ hHeap = winMemGetHeap();
+ assert( hHeap!=0 );
+ assert( hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
+#endif
+ assert( nBytes>=0 );
+ p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
+ if( !p ){
+ sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%lu), heap=%p",
+ nBytes, osGetLastError(), (void*)hHeap);
+ }
+ return p;
+}
+
+/*
+** Free memory.
+*/
+static void winMemFree(void *pPrior){
+ HANDLE hHeap;
+
+ winMemAssertMagic();
+ hHeap = winMemGetHeap();
+ assert( hHeap!=0 );
+ assert( hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
+#endif
+ if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */
+ if( !osHeapFree(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) ){
+ sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%lu), heap=%p",
+ pPrior, osGetLastError(), (void*)hHeap);
+ }
+}
+
+/*
+** Change the size of an existing memory allocation
+*/
+static void *winMemRealloc(void *pPrior, int nBytes){
+ HANDLE hHeap;
+ void *p;
+
+ winMemAssertMagic();
+ hHeap = winMemGetHeap();
+ assert( hHeap!=0 );
+ assert( hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
+#endif
+ assert( nBytes>=0 );
+ if( !pPrior ){
+ p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
+ }else{
+ p = osHeapReAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior, (SIZE_T)nBytes);
+ }
+ if( !p ){
+ sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%lu), heap=%p",
+ pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, osGetLastError(),
+ (void*)hHeap);
+ }
+ return p;
+}
+
+/*
+** Return the size of an outstanding allocation, in bytes.
+*/
+static int winMemSize(void *p){
+ HANDLE hHeap;
+ SIZE_T n;
+
+ winMemAssertMagic();
+ hHeap = winMemGetHeap();
+ assert( hHeap!=0 );
+ assert( hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, p) );
+#endif
+ if( !p ) return 0;
+ n = osHeapSize(hHeap, SQLITE_WIN32_HEAP_FLAGS, p);
+ if( n==(SIZE_T)-1 ){
+ sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%lu), heap=%p",
+ p, osGetLastError(), (void*)hHeap);
+ return 0;
+ }
+ return (int)n;
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int winMemRoundup(int n){
+ return n;
+}
+
+/*
+** Initialize this module.
+*/
+static int winMemInit(void *pAppData){
+ winMemData *pWinMemData = (winMemData *)pAppData;
+
+ if( !pWinMemData ) return SQLITE_ERROR;
+ assert( pWinMemData->magic1==WINMEM_MAGIC1 );
+ assert( pWinMemData->magic2==WINMEM_MAGIC2 );
+
+#if !SQLITE_OS_WINRT && SQLITE_WIN32_HEAP_CREATE
+ if( !pWinMemData->hHeap ){
+ DWORD dwInitialSize = SQLITE_WIN32_HEAP_INIT_SIZE;
+ DWORD dwMaximumSize = (DWORD)sqlite3GlobalConfig.nHeap;
+ if( dwMaximumSize==0 ){
+ dwMaximumSize = SQLITE_WIN32_HEAP_MAX_SIZE;
+ }else if( dwInitialSize>dwMaximumSize ){
+ dwInitialSize = dwMaximumSize;
+ }
+ pWinMemData->hHeap = osHeapCreate(SQLITE_WIN32_HEAP_FLAGS,
+ dwInitialSize, dwMaximumSize);
+ if( !pWinMemData->hHeap ){
+ sqlite3_log(SQLITE_NOMEM,
+ "failed to HeapCreate (%lu), flags=%u, initSize=%lu, maxSize=%lu",
+ osGetLastError(), SQLITE_WIN32_HEAP_FLAGS, dwInitialSize,
+ dwMaximumSize);
+ return SQLITE_NOMEM_BKPT;
+ }
+ pWinMemData->bOwned = TRUE;
+ assert( pWinMemData->bOwned );
+ }
+#else
+ pWinMemData->hHeap = osGetProcessHeap();
+ if( !pWinMemData->hHeap ){
+ sqlite3_log(SQLITE_NOMEM,
+ "failed to GetProcessHeap (%lu)", osGetLastError());
+ return SQLITE_NOMEM_BKPT;
+ }
+ pWinMemData->bOwned = FALSE;
+ assert( !pWinMemData->bOwned );
+#endif
+ assert( pWinMemData->hHeap!=0 );
+ assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
+#endif
+ return SQLITE_OK;
+}
+
+/*
+** Deinitialize this module.
+*/
+static void winMemShutdown(void *pAppData){
+ winMemData *pWinMemData = (winMemData *)pAppData;
+
+ if( !pWinMemData ) return;
+ assert( pWinMemData->magic1==WINMEM_MAGIC1 );
+ assert( pWinMemData->magic2==WINMEM_MAGIC2 );
+
+ if( pWinMemData->hHeap ){
+ assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
+#endif
+ if( pWinMemData->bOwned ){
+ if( !osHeapDestroy(pWinMemData->hHeap) ){
+ sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%lu), heap=%p",
+ osGetLastError(), (void*)pWinMemData->hHeap);
+ }
+ pWinMemData->bOwned = FALSE;
+ }
+ pWinMemData->hHeap = NULL;
+ }
+}
+
+/*
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file. The
+** arguments specify the block of memory to manage.
+**
+** This routine is only called by sqlite3_config(), and therefore
+** is not required to be threadsafe (it is not).
+*/
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetWin32(void){
+ static const sqlite3_mem_methods winMemMethods = {
+ winMemMalloc,
+ winMemFree,
+ winMemRealloc,
+ winMemSize,
+ winMemRoundup,
+ winMemInit,
+ winMemShutdown,
+ &win_mem_data
+ };
+ return &winMemMethods;
+}
+
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+ sqlite3_config(SQLITE_CONFIG_MALLOC, sqlite3MemGetWin32());
+}
+#endif /* SQLITE_WIN32_MALLOC */
+
+/*
+** Convert a UTF-8 string to Microsoft Unicode.
+**
+** Space to hold the returned string is obtained from sqlite3_malloc().
+*/
+static LPWSTR winUtf8ToUnicode(const char *zText){
+ int nChar;
+ LPWSTR zWideText;
+
+ nChar = osMultiByteToWideChar(CP_UTF8, 0, zText, -1, NULL, 0);
+ if( nChar==0 ){
+ return 0;
+ }
+ zWideText = sqlite3MallocZero( nChar*sizeof(WCHAR) );
+ if( zWideText==0 ){
+ return 0;
+ }
+ nChar = osMultiByteToWideChar(CP_UTF8, 0, zText, -1, zWideText,
+ nChar);
+ if( nChar==0 ){
+ sqlite3_free(zWideText);
+ zWideText = 0;
+ }
+ return zWideText;
+}
+
+/*
+** Convert a Microsoft Unicode string to UTF-8.
+**
+** Space to hold the returned string is obtained from sqlite3_malloc().
+*/
+static char *winUnicodeToUtf8(LPCWSTR zWideText){
+ int nByte;
+ char *zText;
+
+ nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideText, -1, 0, 0, 0, 0);
+ if( nByte == 0 ){
+ return 0;
+ }
+ zText = sqlite3MallocZero( nByte );
+ if( zText==0 ){
+ return 0;
+ }
+ nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideText, -1, zText, nByte,
+ 0, 0);
+ if( nByte == 0 ){
+ sqlite3_free(zText);
+ zText = 0;
+ }
+ return zText;
+}
+
+/*
+** Convert an ANSI string to Microsoft Unicode, using the ANSI or OEM
+** code page.
+**
+** Space to hold the returned string is obtained from sqlite3_malloc().
+*/
+static LPWSTR winMbcsToUnicode(const char *zText, int useAnsi){
+ int nByte;
+ LPWSTR zMbcsText;
+ int codepage = useAnsi ? CP_ACP : CP_OEMCP;
+
+ nByte = osMultiByteToWideChar(codepage, 0, zText, -1, NULL,
+ 0)*sizeof(WCHAR);
+ if( nByte==0 ){
+ return 0;
+ }
+ zMbcsText = sqlite3MallocZero( nByte*sizeof(WCHAR) );
+ if( zMbcsText==0 ){
+ return 0;
+ }
+ nByte = osMultiByteToWideChar(codepage, 0, zText, -1, zMbcsText,
+ nByte);
+ if( nByte==0 ){
+ sqlite3_free(zMbcsText);
+ zMbcsText = 0;
+ }
+ return zMbcsText;
+}
+
+/*
+** Convert a Microsoft Unicode string to a multi-byte character string,
+** using the ANSI or OEM code page.
+**
+** Space to hold the returned string is obtained from sqlite3_malloc().
+*/
+static char *winUnicodeToMbcs(LPCWSTR zWideText, int useAnsi){
+ int nByte;
+ char *zText;
+ int codepage = useAnsi ? CP_ACP : CP_OEMCP;
+
+ nByte = osWideCharToMultiByte(codepage, 0, zWideText, -1, 0, 0, 0, 0);
+ if( nByte == 0 ){
+ return 0;
+ }
+ zText = sqlite3MallocZero( nByte );
+ if( zText==0 ){
+ return 0;
+ }
+ nByte = osWideCharToMultiByte(codepage, 0, zWideText, -1, zText,
+ nByte, 0, 0);
+ if( nByte == 0 ){
+ sqlite3_free(zText);
+ zText = 0;
+ }
+ return zText;
+}
+
+/*
+** Convert a multi-byte character string to UTF-8.
+**
+** Space to hold the returned string is obtained from sqlite3_malloc().
+*/
+static char *winMbcsToUtf8(const char *zText, int useAnsi){
+ char *zTextUtf8;
+ LPWSTR zTmpWide;
+
+ zTmpWide = winMbcsToUnicode(zText, useAnsi);
+ if( zTmpWide==0 ){
+ return 0;
+ }
+ zTextUtf8 = winUnicodeToUtf8(zTmpWide);
+ sqlite3_free(zTmpWide);
+ return zTextUtf8;
+}
+
+/*
+** Convert a UTF-8 string to a multi-byte character string.
+**
+** Space to hold the returned string is obtained from sqlite3_malloc().
+*/
+static char *winUtf8ToMbcs(const char *zText, int useAnsi){
+ char *zTextMbcs;
+ LPWSTR zTmpWide;
+
+ zTmpWide = winUtf8ToUnicode(zText);
+ if( zTmpWide==0 ){
+ return 0;
+ }
+ zTextMbcs = winUnicodeToMbcs(zTmpWide, useAnsi);
+ sqlite3_free(zTmpWide);
+ return zTextMbcs;
+}
+
+/*
+** This is a public wrapper for the winUtf8ToUnicode() function.
+*/
+SQLITE_API LPWSTR sqlite3_win32_utf8_to_unicode(const char *zText){
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !zText ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return winUtf8ToUnicode(zText);
+}
+
+/*
+** This is a public wrapper for the winUnicodeToUtf8() function.
+*/
+SQLITE_API char *sqlite3_win32_unicode_to_utf8(LPCWSTR zWideText){
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !zWideText ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return winUnicodeToUtf8(zWideText);
+}
+
+/*
+** This is a public wrapper for the winMbcsToUtf8() function.
+*/
+SQLITE_API char *sqlite3_win32_mbcs_to_utf8(const char *zText){
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !zText ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return winMbcsToUtf8(zText, osAreFileApisANSI());
+}
+
+/*
+** This is a public wrapper for the winMbcsToUtf8() function.
+*/
+SQLITE_API char *sqlite3_win32_mbcs_to_utf8_v2(const char *zText, int useAnsi){
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !zText ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return winMbcsToUtf8(zText, useAnsi);
+}
+
+/*
+** This is a public wrapper for the winUtf8ToMbcs() function.
+*/
+SQLITE_API char *sqlite3_win32_utf8_to_mbcs(const char *zText){
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !zText ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return winUtf8ToMbcs(zText, osAreFileApisANSI());
+}
+
+/*
+** This is a public wrapper for the winUtf8ToMbcs() function.
+*/
+SQLITE_API char *sqlite3_win32_utf8_to_mbcs_v2(const char *zText, int useAnsi){
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !zText ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return winUtf8ToMbcs(zText, useAnsi);
+}
+
+/*
+** This function is the same as sqlite3_win32_set_directory (below); however,
+** it accepts a UTF-8 string.
+*/
+SQLITE_API int sqlite3_win32_set_directory8(
+ unsigned long type, /* Identifier for directory being set or reset */
+ const char *zValue /* New value for directory being set or reset */
+){
+ char **ppDirectory = 0;
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return rc;
+#endif
+ if( type==SQLITE_WIN32_DATA_DIRECTORY_TYPE ){
+ ppDirectory = &sqlite3_data_directory;
+ }else if( type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE ){
+ ppDirectory = &sqlite3_temp_directory;
+ }
+ assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
+ || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
+ );
+ assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
+ if( ppDirectory ){
+ char *zCopy = 0;
+ if( zValue && zValue[0] ){
+ zCopy = sqlite3_mprintf("%s", zValue);
+ if ( zCopy==0 ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ }
+ sqlite3_free(*ppDirectory);
+ *ppDirectory = zCopy;
+ return SQLITE_OK;
+ }
+ return SQLITE_ERROR;
+}
+
+/*
+** This function is the same as sqlite3_win32_set_directory (below); however,
+** it accepts a UTF-16 string.
+*/
+SQLITE_API int sqlite3_win32_set_directory16(
+ unsigned long type, /* Identifier for directory being set or reset */
+ const void *zValue /* New value for directory being set or reset */
+){
+ int rc;
+ char *zUtf8 = 0;
+ if( zValue ){
+ zUtf8 = sqlite3_win32_unicode_to_utf8(zValue);
+ if( zUtf8==0 ) return SQLITE_NOMEM_BKPT;
+ }
+ rc = sqlite3_win32_set_directory8(type, zUtf8);
+ if( zUtf8 ) sqlite3_free(zUtf8);
+ return rc;
+}
+
+/*
+** This function sets the data directory or the temporary directory based on
+** the provided arguments. The type argument must be 1 in order to set the
+** data directory or 2 in order to set the temporary directory. The zValue
+** argument is the name of the directory to use. The return value will be
+** SQLITE_OK if successful.
+*/
+SQLITE_API int sqlite3_win32_set_directory(
+ unsigned long type, /* Identifier for directory being set or reset */
+ void *zValue /* New value for directory being set or reset */
+){
+ return sqlite3_win32_set_directory16(type, zValue);
+}
+
+/*
+** The return value of winGetLastErrorMsg
+** is zero if the error message fits in the buffer, or non-zero
+** otherwise (if the message was truncated).
+*/
+static int winGetLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
+ /* FormatMessage returns 0 on failure. Otherwise it
+ ** returns the number of TCHARs written to the output
+ ** buffer, excluding the terminating null char.
+ */
+ DWORD dwLen = 0;
+ char *zOut = 0;
+
+ if( osIsNT() ){
+#if SQLITE_OS_WINRT
+ WCHAR zTempWide[SQLITE_WIN32_MAX_ERRMSG_CHARS+1];
+ dwLen = osFormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM |
+ FORMAT_MESSAGE_IGNORE_INSERTS,
+ NULL,
+ lastErrno,
+ 0,
+ zTempWide,
+ SQLITE_WIN32_MAX_ERRMSG_CHARS,
+ 0);
+#else
+ LPWSTR zTempWide = NULL;
+ dwLen = osFormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+ FORMAT_MESSAGE_FROM_SYSTEM |
+ FORMAT_MESSAGE_IGNORE_INSERTS,
+ NULL,
+ lastErrno,
+ 0,
+ (LPWSTR) &zTempWide,
+ 0,
+ 0);
+#endif
+ if( dwLen > 0 ){
+ /* allocate a buffer and convert to UTF8 */
+ sqlite3BeginBenignMalloc();
+ zOut = winUnicodeToUtf8(zTempWide);
+ sqlite3EndBenignMalloc();
+#if !SQLITE_OS_WINRT
+ /* free the system buffer allocated by FormatMessage */
+ osLocalFree(zTempWide);
+#endif
+ }
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ char *zTemp = NULL;
+ dwLen = osFormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+ FORMAT_MESSAGE_FROM_SYSTEM |
+ FORMAT_MESSAGE_IGNORE_INSERTS,
+ NULL,
+ lastErrno,
+ 0,
+ (LPSTR) &zTemp,
+ 0,
+ 0);
+ if( dwLen > 0 ){
+ /* allocate a buffer and convert to UTF8 */
+ sqlite3BeginBenignMalloc();
+ zOut = winMbcsToUtf8(zTemp, osAreFileApisANSI());
+ sqlite3EndBenignMalloc();
+ /* free the system buffer allocated by FormatMessage */
+ osLocalFree(zTemp);
+ }
+ }
+#endif
+ if( 0 == dwLen ){
+ sqlite3_snprintf(nBuf, zBuf, "OsError 0x%lx (%lu)", lastErrno, lastErrno);
+ }else{
+ /* copy a maximum of nBuf chars to output buffer */
+ sqlite3_snprintf(nBuf, zBuf, "%s", zOut);
+ /* free the UTF8 buffer */
+ sqlite3_free(zOut);
+ }
+ return 0;
+}
+
+/*
+**
+** This function - winLogErrorAtLine() - is only ever called via the macro
+** winLogError().
+**
+** This routine is invoked after an error occurs in an OS function.
+** It logs a message using sqlite3_log() containing the current value of
+** error code and, if possible, the human-readable equivalent from
+** FormatMessage.
+**
+** The first argument passed to the macro should be the error code that
+** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN).
+** The two subsequent arguments should be the name of the OS function that
+** failed and the associated file-system path, if any.
+*/
+#define winLogError(a,b,c,d) winLogErrorAtLine(a,b,c,d,__LINE__)
+static int winLogErrorAtLine(
+ int errcode, /* SQLite error code */
+ DWORD lastErrno, /* Win32 last error */
+ const char *zFunc, /* Name of OS function that failed */
+ const char *zPath, /* File path associated with error */
+ int iLine /* Source line number where error occurred */
+){
+ char zMsg[500]; /* Human readable error text */
+ int i; /* Loop counter */
+
+ zMsg[0] = 0;
+ winGetLastErrorMsg(lastErrno, sizeof(zMsg), zMsg);
+ assert( errcode!=SQLITE_OK );
+ if( zPath==0 ) zPath = "";
+ for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
+ zMsg[i] = 0;
+ sqlite3_log(errcode,
+ "os_win.c:%d: (%lu) %s(%s) - %s",
+ iLine, lastErrno, zFunc, zPath, zMsg
+ );
+
+ return errcode;
+}
+
+/*
+** The number of times that a ReadFile(), WriteFile(), and DeleteFile()
+** will be retried following a locking error - probably caused by
+** antivirus software. Also the initial delay before the first retry.
+** The delay increases linearly with each retry.
+*/
+#ifndef SQLITE_WIN32_IOERR_RETRY
+# define SQLITE_WIN32_IOERR_RETRY 10
+#endif
+#ifndef SQLITE_WIN32_IOERR_RETRY_DELAY
+# define SQLITE_WIN32_IOERR_RETRY_DELAY 25
+#endif
+static int winIoerrRetry = SQLITE_WIN32_IOERR_RETRY;
+static int winIoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY;
+
+/*
+** The "winIoerrCanRetry1" macro is used to determine if a particular I/O
+** error code obtained via GetLastError() is eligible to be retried. It
+** must accept the error code DWORD as its only argument and should return
+** non-zero if the error code is transient in nature and the operation
+** responsible for generating the original error might succeed upon being
+** retried. The argument to this macro should be a variable.
+**
+** Additionally, a macro named "winIoerrCanRetry2" may be defined. If it
+** is defined, it will be consulted only when the macro "winIoerrCanRetry1"
+** returns zero. The "winIoerrCanRetry2" macro is completely optional and
+** may be used to include additional error codes in the set that should
+** result in the failing I/O operation being retried by the caller. If
+** defined, the "winIoerrCanRetry2" macro must exhibit external semantics
+** identical to those of the "winIoerrCanRetry1" macro.
+*/
+#if !defined(winIoerrCanRetry1)
+#define winIoerrCanRetry1(a) (((a)==ERROR_ACCESS_DENIED) || \
+ ((a)==ERROR_SHARING_VIOLATION) || \
+ ((a)==ERROR_LOCK_VIOLATION) || \
+ ((a)==ERROR_DEV_NOT_EXIST) || \
+ ((a)==ERROR_NETNAME_DELETED) || \
+ ((a)==ERROR_SEM_TIMEOUT) || \
+ ((a)==ERROR_NETWORK_UNREACHABLE))
+#endif
+
+/*
+** If a ReadFile() or WriteFile() error occurs, invoke this routine
+** to see if it should be retried. Return TRUE to retry. Return FALSE
+** to give up with an error.
+*/
+static int winRetryIoerr(int *pnRetry, DWORD *pError){
+ DWORD e = osGetLastError();
+ if( *pnRetry>=winIoerrRetry ){
+ if( pError ){
+ *pError = e;
+ }
+ return 0;
+ }
+ if( winIoerrCanRetry1(e) ){
+ sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
+ ++*pnRetry;
+ return 1;
+ }
+#if defined(winIoerrCanRetry2)
+ else if( winIoerrCanRetry2(e) ){
+ sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
+ ++*pnRetry;
+ return 1;
+ }
+#endif
+ if( pError ){
+ *pError = e;
+ }
+ return 0;
+}
+
+/*
+** Log a I/O error retry episode.
+*/
+static void winLogIoerr(int nRetry, int lineno){
+ if( nRetry ){
+ sqlite3_log(SQLITE_NOTICE,
+ "delayed %dms for lock/sharing conflict at line %d",
+ winIoerrRetryDelay*nRetry*(nRetry+1)/2, lineno
+ );
+ }
+}
+
+/*
+** This #if does not rely on the SQLITE_OS_WINCE define because the
+** corresponding section in "date.c" cannot use it.
+*/
+#if !defined(SQLITE_OMIT_LOCALTIME) && defined(_WIN32_WCE) && \
+ (!defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API)
+/*
+** The MSVC CRT on Windows CE may not have a localtime() function.
+** So define a substitute.
+*/
+/* # include */
+struct tm *__cdecl localtime(const time_t *t)
+{
+ static struct tm y;
+ FILETIME uTm, lTm;
+ SYSTEMTIME pTm;
+ sqlite3_int64 t64;
+ t64 = *t;
+ t64 = (t64 + 11644473600)*10000000;
+ uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF);
+ uTm.dwHighDateTime= (DWORD)(t64 >> 32);
+ osFileTimeToLocalFileTime(&uTm,&lTm);
+ osFileTimeToSystemTime(&lTm,&pTm);
+ y.tm_year = pTm.wYear - 1900;
+ y.tm_mon = pTm.wMonth - 1;
+ y.tm_wday = pTm.wDayOfWeek;
+ y.tm_mday = pTm.wDay;
+ y.tm_hour = pTm.wHour;
+ y.tm_min = pTm.wMinute;
+ y.tm_sec = pTm.wSecond;
+ return &y;
+}
+#endif
+
+#if SQLITE_OS_WINCE
+/*************************************************************************
+** This section contains code for WinCE only.
+*/
+#define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]
+
+/*
+** Acquire a lock on the handle h
+*/
+static void winceMutexAcquire(HANDLE h){
+ DWORD dwErr;
+ do {
+ dwErr = osWaitForSingleObject(h, INFINITE);
+ } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED);
+}
+/*
+** Release a lock acquired by winceMutexAcquire()
+*/
+#define winceMutexRelease(h) ReleaseMutex(h)
+
+/*
+** Create the mutex and shared memory used for locking in the file
+** descriptor pFile
+*/
+static int winceCreateLock(const char *zFilename, winFile *pFile){
+ LPWSTR zTok;
+ LPWSTR zName;
+ DWORD lastErrno;
+ BOOL bLogged = FALSE;
+ BOOL bInit = TRUE;
+
+ zName = winUtf8ToUnicode(zFilename);
+ if( zName==0 ){
+ /* out of memory */
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+
+ /* Initialize the local lockdata */
+ memset(&pFile->local, 0, sizeof(pFile->local));
+
+ /* Replace the backslashes from the filename and lowercase it
+ ** to derive a mutex name. */
+ zTok = osCharLowerW(zName);
+ for (;*zTok;zTok++){
+ if (*zTok == '\\') *zTok = '_';
+ }
+
+ /* Create/open the named mutex */
+ pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
+ if (!pFile->hMutex){
+ pFile->lastErrno = osGetLastError();
+ sqlite3_free(zName);
+ return winLogError(SQLITE_IOERR, pFile->lastErrno,
+ "winceCreateLock1", zFilename);
+ }
+
+ /* Acquire the mutex before continuing */
+ winceMutexAcquire(pFile->hMutex);
+
+ /* Since the names of named mutexes, semaphores, file mappings etc are
+ ** case-sensitive, take advantage of that by uppercasing the mutex name
+ ** and using that as the shared filemapping name.
+ */
+ osCharUpperW(zName);
+ pFile->hShared = osCreateFileMappingW(INVALID_HANDLE_VALUE, NULL,
+ PAGE_READWRITE, 0, sizeof(winceLock),
+ zName);
+
+ /* Set a flag that indicates we're the first to create the memory so it
+ ** must be zero-initialized */
+ lastErrno = osGetLastError();
+ if (lastErrno == ERROR_ALREADY_EXISTS){
+ bInit = FALSE;
+ }
+
+ sqlite3_free(zName);
+
+ /* If we succeeded in making the shared memory handle, map it. */
+ if( pFile->hShared ){
+ pFile->shared = (winceLock*)osMapViewOfFile(pFile->hShared,
+ FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
+ /* If mapping failed, close the shared memory handle and erase it */
+ if( !pFile->shared ){
+ pFile->lastErrno = osGetLastError();
+ winLogError(SQLITE_IOERR, pFile->lastErrno,
+ "winceCreateLock2", zFilename);
+ bLogged = TRUE;
+ osCloseHandle(pFile->hShared);
+ pFile->hShared = NULL;
+ }
+ }
+
+ /* If shared memory could not be created, then close the mutex and fail */
+ if( pFile->hShared==NULL ){
+ if( !bLogged ){
+ pFile->lastErrno = lastErrno;
+ winLogError(SQLITE_IOERR, pFile->lastErrno,
+ "winceCreateLock3", zFilename);
+ bLogged = TRUE;
+ }
+ winceMutexRelease(pFile->hMutex);
+ osCloseHandle(pFile->hMutex);
+ pFile->hMutex = NULL;
+ return SQLITE_IOERR;
+ }
+
+ /* Initialize the shared memory if we're supposed to */
+ if( bInit ){
+ memset(pFile->shared, 0, sizeof(winceLock));
+ }
+
+ winceMutexRelease(pFile->hMutex);
+ return SQLITE_OK;
+}
+
+/*
+** Destroy the part of winFile that deals with wince locks
+*/
+static void winceDestroyLock(winFile *pFile){
+ if (pFile->hMutex){
+ /* Acquire the mutex */
+ winceMutexAcquire(pFile->hMutex);
+
+ /* The following blocks should probably assert in debug mode, but they
+ are to cleanup in case any locks remained open */
+ if (pFile->local.nReaders){
+ pFile->shared->nReaders --;
+ }
+ if (pFile->local.bReserved){
+ pFile->shared->bReserved = FALSE;
+ }
+ if (pFile->local.bPending){
+ pFile->shared->bPending = FALSE;
+ }
+ if (pFile->local.bExclusive){
+ pFile->shared->bExclusive = FALSE;
+ }
+
+ /* De-reference and close our copy of the shared memory handle */
+ osUnmapViewOfFile(pFile->shared);
+ osCloseHandle(pFile->hShared);
+
+ /* Done with the mutex */
+ winceMutexRelease(pFile->hMutex);
+ osCloseHandle(pFile->hMutex);
+ pFile->hMutex = NULL;
+ }
+}
+
+/*
+** An implementation of the LockFile() API of Windows for CE
+*/
+static BOOL winceLockFile(
+ LPHANDLE phFile,
+ DWORD dwFileOffsetLow,
+ DWORD dwFileOffsetHigh,
+ DWORD nNumberOfBytesToLockLow,
+ DWORD nNumberOfBytesToLockHigh
+){
+ winFile *pFile = HANDLE_TO_WINFILE(phFile);
+ BOOL bReturn = FALSE;
+
+ UNUSED_PARAMETER(dwFileOffsetHigh);
+ UNUSED_PARAMETER(nNumberOfBytesToLockHigh);
+
+ if (!pFile->hMutex) return TRUE;
+ winceMutexAcquire(pFile->hMutex);
+
+ /* Wanting an exclusive lock? */
+ if (dwFileOffsetLow == (DWORD)SHARED_FIRST
+ && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){
+ if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){
+ pFile->shared->bExclusive = TRUE;
+ pFile->local.bExclusive = TRUE;
+ bReturn = TRUE;
+ }
+ }
+
+ /* Want a read-only lock? */
+ else if (dwFileOffsetLow == (DWORD)SHARED_FIRST &&
+ nNumberOfBytesToLockLow == 1){
+ if (pFile->shared->bExclusive == 0){
+ pFile->local.nReaders ++;
+ if (pFile->local.nReaders == 1){
+ pFile->shared->nReaders ++;
+ }
+ bReturn = TRUE;
+ }
+ }
+
+ /* Want a pending lock? */
+ else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
+ && nNumberOfBytesToLockLow == 1){
+ /* If no pending lock has been acquired, then acquire it */
+ if (pFile->shared->bPending == 0) {
+ pFile->shared->bPending = TRUE;
+ pFile->local.bPending = TRUE;
+ bReturn = TRUE;
+ }
+ }
+
+ /* Want a reserved lock? */
+ else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
+ && nNumberOfBytesToLockLow == 1){
+ if (pFile->shared->bReserved == 0) {
+ pFile->shared->bReserved = TRUE;
+ pFile->local.bReserved = TRUE;
+ bReturn = TRUE;
+ }
+ }
+
+ winceMutexRelease(pFile->hMutex);
+ return bReturn;
+}
+
+/*
+** An implementation of the UnlockFile API of Windows for CE
+*/
+static BOOL winceUnlockFile(
+ LPHANDLE phFile,
+ DWORD dwFileOffsetLow,
+ DWORD dwFileOffsetHigh,
+ DWORD nNumberOfBytesToUnlockLow,
+ DWORD nNumberOfBytesToUnlockHigh
+){
+ winFile *pFile = HANDLE_TO_WINFILE(phFile);
+ BOOL bReturn = FALSE;
+
+ UNUSED_PARAMETER(dwFileOffsetHigh);
+ UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh);
+
+ if (!pFile->hMutex) return TRUE;
+ winceMutexAcquire(pFile->hMutex);
+
+ /* Releasing a reader lock or an exclusive lock */
+ if (dwFileOffsetLow == (DWORD)SHARED_FIRST){
+ /* Did we have an exclusive lock? */
+ if (pFile->local.bExclusive){
+ assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE);
+ pFile->local.bExclusive = FALSE;
+ pFile->shared->bExclusive = FALSE;
+ bReturn = TRUE;
+ }
+
+ /* Did we just have a reader lock? */
+ else if (pFile->local.nReaders){
+ assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE
+ || nNumberOfBytesToUnlockLow == 1);
+ pFile->local.nReaders --;
+ if (pFile->local.nReaders == 0)
+ {
+ pFile->shared->nReaders --;
+ }
+ bReturn = TRUE;
+ }
+ }
+
+ /* Releasing a pending lock */
+ else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
+ && nNumberOfBytesToUnlockLow == 1){
+ if (pFile->local.bPending){
+ pFile->local.bPending = FALSE;
+ pFile->shared->bPending = FALSE;
+ bReturn = TRUE;
+ }
+ }
+ /* Releasing a reserved lock */
+ else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
+ && nNumberOfBytesToUnlockLow == 1){
+ if (pFile->local.bReserved) {
+ pFile->local.bReserved = FALSE;
+ pFile->shared->bReserved = FALSE;
+ bReturn = TRUE;
+ }
+ }
+
+ winceMutexRelease(pFile->hMutex);
+ return bReturn;
+}
+/*
+** End of the special code for wince
+*****************************************************************************/
+#endif /* SQLITE_OS_WINCE */
+
+/*
+** Lock a file region.
+*/
+static BOOL winLockFile(
+ LPHANDLE phFile,
+ DWORD flags,
+ DWORD offsetLow,
+ DWORD offsetHigh,
+ DWORD numBytesLow,
+ DWORD numBytesHigh
+){
+#if SQLITE_OS_WINCE
+ /*
+ ** NOTE: Windows CE is handled differently here due its lack of the Win32
+ ** API LockFile.
+ */
+ return winceLockFile(phFile, offsetLow, offsetHigh,
+ numBytesLow, numBytesHigh);
+#else
+ if( osIsNT() ){
+ OVERLAPPED ovlp;
+ memset(&ovlp, 0, sizeof(OVERLAPPED));
+ ovlp.Offset = offsetLow;
+ ovlp.OffsetHigh = offsetHigh;
+ return osLockFileEx(*phFile, flags, 0, numBytesLow, numBytesHigh, &ovlp);
+ }else{
+ return osLockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
+ numBytesHigh);
+ }
+#endif
+}
+
+/*
+** Unlock a file region.
+ */
+static BOOL winUnlockFile(
+ LPHANDLE phFile,
+ DWORD offsetLow,
+ DWORD offsetHigh,
+ DWORD numBytesLow,
+ DWORD numBytesHigh
+){
+#if SQLITE_OS_WINCE
+ /*
+ ** NOTE: Windows CE is handled differently here due its lack of the Win32
+ ** API UnlockFile.
+ */
+ return winceUnlockFile(phFile, offsetLow, offsetHigh,
+ numBytesLow, numBytesHigh);
+#else
+ if( osIsNT() ){
+ OVERLAPPED ovlp;
+ memset(&ovlp, 0, sizeof(OVERLAPPED));
+ ovlp.Offset = offsetLow;
+ ovlp.OffsetHigh = offsetHigh;
+ return osUnlockFileEx(*phFile, 0, numBytesLow, numBytesHigh, &ovlp);
+ }else{
+ return osUnlockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
+ numBytesHigh);
+ }
+#endif
+}
+
+/*****************************************************************************
+** The next group of routines implement the I/O methods specified
+** by the sqlite3_io_methods object.
+******************************************************************************/
+
+/*
+** Some Microsoft compilers lack this definition.
+*/
+#ifndef INVALID_SET_FILE_POINTER
+# define INVALID_SET_FILE_POINTER ((DWORD)-1)
+#endif
+
+/*
+** Move the current position of the file handle passed as the first
+** argument to offset iOffset within the file. If successful, return 0.
+** Otherwise, set pFile->lastErrno and return non-zero.
+*/
+static int winSeekFile(winFile *pFile, sqlite3_int64 iOffset){
+#if !SQLITE_OS_WINRT
+ LONG upperBits; /* Most sig. 32 bits of new offset */
+ LONG lowerBits; /* Least sig. 32 bits of new offset */
+ DWORD dwRet; /* Value returned by SetFilePointer() */
+ DWORD lastErrno; /* Value returned by GetLastError() */
+
+ OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
+
+ upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
+ lowerBits = (LONG)(iOffset & 0xffffffff);
+
+ /* API oddity: If successful, SetFilePointer() returns a dword
+ ** containing the lower 32-bits of the new file-offset. Or, if it fails,
+ ** it returns INVALID_SET_FILE_POINTER. However according to MSDN,
+ ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine
+ ** whether an error has actually occurred, it is also necessary to call
+ ** GetLastError().
+ */
+ dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
+
+ if( (dwRet==INVALID_SET_FILE_POINTER
+ && ((lastErrno = osGetLastError())!=NO_ERROR)) ){
+ pFile->lastErrno = lastErrno;
+ winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
+ "winSeekFile", pFile->zPath);
+ OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
+ return 1;
+ }
+
+ OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
+ return 0;
+#else
+ /*
+ ** Same as above, except that this implementation works for WinRT.
+ */
+
+ LARGE_INTEGER x; /* The new offset */
+ BOOL bRet; /* Value returned by SetFilePointerEx() */
+
+ x.QuadPart = iOffset;
+ bRet = osSetFilePointerEx(pFile->h, x, 0, FILE_BEGIN);
+
+ if(!bRet){
+ pFile->lastErrno = osGetLastError();
+ winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
+ "winSeekFile", pFile->zPath);
+ OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
+ return 1;
+ }
+
+ OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
+ return 0;
+#endif
+}
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/* Forward references to VFS helper methods used for memory mapped files */
+static int winMapfile(winFile*, sqlite3_int64);
+static int winUnmapfile(winFile*);
+#endif
+
+/*
+** Close a file.
+**
+** It is reported that an attempt to close a handle might sometimes
+** fail. This is a very unreasonable result, but Windows is notorious
+** for being unreasonable so I do not doubt that it might happen. If
+** the close fails, we pause for 100 milliseconds and try again. As
+** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
+** giving up and returning an error.
+*/
+#define MX_CLOSE_ATTEMPT 3
+static int winClose(sqlite3_file *id){
+ int rc, cnt = 0;
+ winFile *pFile = (winFile*)id;
+
+ assert( id!=0 );
+#ifndef SQLITE_OMIT_WAL
+ assert( pFile->pShm==0 );
+#endif
+ assert( pFile->h!=NULL && pFile->h!=INVALID_HANDLE_VALUE );
+ OSTRACE(("CLOSE pid=%lu, pFile=%p, file=%p\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ winUnmapfile(pFile);
+#endif
+
+ do{
+ rc = osCloseHandle(pFile->h);
+ /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
+ }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (sqlite3_win32_sleep(100), 1) );
+#if SQLITE_OS_WINCE
+#define WINCE_DELETION_ATTEMPTS 3
+ {
+ winVfsAppData *pAppData = (winVfsAppData*)pFile->pVfs->pAppData;
+ if( pAppData==NULL || !pAppData->bNoLock ){
+ winceDestroyLock(pFile);
+ }
+ }
+ if( pFile->zDeleteOnClose ){
+ int cnt = 0;
+ while(
+ osDeleteFileW(pFile->zDeleteOnClose)==0
+ && osGetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff
+ && cnt++ < WINCE_DELETION_ATTEMPTS
+ ){
+ sqlite3_win32_sleep(100); /* Wait a little before trying again */
+ }
+ sqlite3_free(pFile->zDeleteOnClose);
+ }
+#endif
+ if( rc ){
+ pFile->h = NULL;
+ }
+ OpenCounter(-1);
+ OSTRACE(("CLOSE pid=%lu, pFile=%p, file=%p, rc=%s\n",
+ osGetCurrentProcessId(), pFile, pFile->h, rc ? "ok" : "failed"));
+ return rc ? SQLITE_OK
+ : winLogError(SQLITE_IOERR_CLOSE, osGetLastError(),
+ "winClose", pFile->zPath);
+}
+
+/*
+** Read data from a file into a buffer. Return SQLITE_OK if all
+** bytes were read successfully and SQLITE_IOERR if anything goes
+** wrong.
+*/
+static int winRead(
+ sqlite3_file *id, /* File to read from */
+ void *pBuf, /* Write content into this buffer */
+ int amt, /* Number of bytes to read */
+ sqlite3_int64 offset /* Begin reading at this offset */
+){
+#if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
+ OVERLAPPED overlapped; /* The offset for ReadFile. */
+#endif
+ winFile *pFile = (winFile*)id; /* file handle */
+ DWORD nRead; /* Number of bytes actually read from file */
+ int nRetry = 0; /* Number of retrys */
+
+ assert( id!=0 );
+ assert( amt>0 );
+ assert( offset>=0 );
+ SimulateIOError(return SQLITE_IOERR_READ);
+ OSTRACE(("READ pid=%lu, pFile=%p, file=%p, buffer=%p, amount=%d, "
+ "offset=%lld, lock=%d\n", osGetCurrentProcessId(), pFile,
+ pFile->h, pBuf, amt, offset, pFile->locktype));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* Deal with as much of this read request as possible by transfering
+ ** data from the memory mapping using memcpy(). */
+ if( offsetmmapSize ){
+ if( offset+amt <= pFile->mmapSize ){
+ memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
+ OSTRACE(("READ-MMAP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return SQLITE_OK;
+ }else{
+ int nCopy = (int)(pFile->mmapSize - offset);
+ memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
+ pBuf = &((u8 *)pBuf)[nCopy];
+ amt -= nCopy;
+ offset += nCopy;
+ }
+ }
+#endif
+
+#if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
+ if( winSeekFile(pFile, offset) ){
+ OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_FULL\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return SQLITE_FULL;
+ }
+ while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
+#else
+ memset(&overlapped, 0, sizeof(OVERLAPPED));
+ overlapped.Offset = (LONG)(offset & 0xffffffff);
+ overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
+ while( !osReadFile(pFile->h, pBuf, amt, &nRead, &overlapped) &&
+ osGetLastError()!=ERROR_HANDLE_EOF ){
+#endif
+ DWORD lastErrno;
+ if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
+ pFile->lastErrno = lastErrno;
+ OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_READ\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
+ "winRead", pFile->zPath);
+ }
+ winLogIoerr(nRetry, __LINE__);
+ if( nRead<(DWORD)amt ){
+ /* Unread parts of the buffer must be zero-filled */
+ memset(&((char*)pBuf)[nRead], 0, amt-nRead);
+ OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_SHORT_READ\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return SQLITE_IOERR_SHORT_READ;
+ }
+
+ OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return SQLITE_OK;
+}
+
+/*
+** Write data from a buffer into a file. Return SQLITE_OK on success
+** or some other error code on failure.
+*/
+static int winWrite(
+ sqlite3_file *id, /* File to write into */
+ const void *pBuf, /* The bytes to be written */
+ int amt, /* Number of bytes to write */
+ sqlite3_int64 offset /* Offset into the file to begin writing at */
+){
+ int rc = 0; /* True if error has occurred, else false */
+ winFile *pFile = (winFile*)id; /* File handle */
+ int nRetry = 0; /* Number of retries */
+
+ assert( amt>0 );
+ assert( pFile );
+ SimulateIOError(return SQLITE_IOERR_WRITE);
+ SimulateDiskfullError(return SQLITE_FULL);
+
+ OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, buffer=%p, amount=%d, "
+ "offset=%lld, lock=%d\n", osGetCurrentProcessId(), pFile,
+ pFile->h, pBuf, amt, offset, pFile->locktype));
+
+#if defined(SQLITE_MMAP_READWRITE) && SQLITE_MAX_MMAP_SIZE>0
+ /* Deal with as much of this write request as possible by transfering
+ ** data from the memory mapping using memcpy(). */
+ if( offsetmmapSize ){
+ if( offset+amt <= pFile->mmapSize ){
+ memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
+ OSTRACE(("WRITE-MMAP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return SQLITE_OK;
+ }else{
+ int nCopy = (int)(pFile->mmapSize - offset);
+ memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
+ pBuf = &((u8 *)pBuf)[nCopy];
+ amt -= nCopy;
+ offset += nCopy;
+ }
+ }
+#endif
+
+#if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
+ rc = winSeekFile(pFile, offset);
+ if( rc==0 ){
+#else
+ {
+#endif
+#if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
+ OVERLAPPED overlapped; /* The offset for WriteFile. */
+#endif
+ u8 *aRem = (u8 *)pBuf; /* Data yet to be written */
+ int nRem = amt; /* Number of bytes yet to be written */
+ DWORD nWrite; /* Bytes written by each WriteFile() call */
+ DWORD lastErrno = NO_ERROR; /* Value returned by GetLastError() */
+
+#if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
+ memset(&overlapped, 0, sizeof(OVERLAPPED));
+ overlapped.Offset = (LONG)(offset & 0xffffffff);
+ overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
+#endif
+
+ while( nRem>0 ){
+#if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
+ if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){
+#else
+ if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, &overlapped) ){
+#endif
+ if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
+ break;
+ }
+ assert( nWrite==0 || nWrite<=(DWORD)nRem );
+ if( nWrite==0 || nWrite>(DWORD)nRem ){
+ lastErrno = osGetLastError();
+ break;
+ }
+#if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
+ offset += nWrite;
+ overlapped.Offset = (LONG)(offset & 0xffffffff);
+ overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
+#endif
+ aRem += nWrite;
+ nRem -= nWrite;
+ }
+ if( nRem>0 ){
+ pFile->lastErrno = lastErrno;
+ rc = 1;
+ }
+ }
+
+ if( rc ){
+ if( ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
+ || ( pFile->lastErrno==ERROR_DISK_FULL )){
+ OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_FULL\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return winLogError(SQLITE_FULL, pFile->lastErrno,
+ "winWrite1", pFile->zPath);
+ }
+ OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_WRITE\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
+ "winWrite2", pFile->zPath);
+ }else{
+ winLogIoerr(nRetry, __LINE__);
+ }
+ OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return SQLITE_OK;
+}
+
+/*
+** Truncate an open file to a specified size
+*/
+static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
+ winFile *pFile = (winFile*)id; /* File handle object */
+ int rc = SQLITE_OK; /* Return code for this function */
+ DWORD lastErrno;
+#if SQLITE_MAX_MMAP_SIZE>0
+ sqlite3_int64 oldMmapSize;
+#endif
+
+ assert( pFile );
+ SimulateIOError(return SQLITE_IOERR_TRUNCATE);
+ OSTRACE(("TRUNCATE pid=%lu, pFile=%p, file=%p, size=%lld, lock=%d\n",
+ osGetCurrentProcessId(), pFile, pFile->h, nByte, pFile->locktype));
+
+ /* If the user has configured a chunk-size for this file, truncate the
+ ** file so that it consists of an integer number of chunks (i.e. the
+ ** actual file size after the operation may be larger than the requested
+ ** size).
+ */
+ if( pFile->szChunk>0 ){
+ nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+ }
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ if( pFile->pMapRegion ){
+ oldMmapSize = pFile->mmapSize;
+ }else{
+ oldMmapSize = 0;
+ }
+ winUnmapfile(pFile);
+#endif
+
+ /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
+ if( winSeekFile(pFile, nByte) ){
+ rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
+ "winTruncate1", pFile->zPath);
+ }else if( 0==osSetEndOfFile(pFile->h) &&
+ ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
+ pFile->lastErrno = lastErrno;
+ rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
+ "winTruncate2", pFile->zPath);
+ }
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ if( rc==SQLITE_OK && oldMmapSize>0 ){
+ if( oldMmapSize>nByte ){
+ winMapfile(pFile, -1);
+ }else{
+ winMapfile(pFile, oldMmapSize);
+ }
+ }
+#endif
+
+ OSTRACE(("TRUNCATE pid=%lu, pFile=%p, file=%p, rc=%s\n",
+ osGetCurrentProcessId(), pFile, pFile->h, sqlite3ErrName(rc)));
+ return rc;
+}
+
+#ifdef SQLITE_TEST
+/*
+** Count the number of fullsyncs and normal syncs. This is used to test
+** that syncs and fullsyncs are occuring at the right times.
+*/
+SQLITE_API int sqlite3_sync_count = 0;
+SQLITE_API int sqlite3_fullsync_count = 0;
+#endif
+
+/*
+** Make sure all writes to a particular file are committed to disk.
+*/
+static int winSync(sqlite3_file *id, int flags){
+#ifndef SQLITE_NO_SYNC
+ /*
+ ** Used only when SQLITE_NO_SYNC is not defined.
+ */
+ BOOL rc;
+#endif
+#if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || \
+ defined(SQLITE_HAVE_OS_TRACE)
+ /*
+ ** Used when SQLITE_NO_SYNC is not defined and by the assert() and/or
+ ** OSTRACE() macros.
+ */
+ winFile *pFile = (winFile*)id;
+#else
+ UNUSED_PARAMETER(id);
+#endif
+
+ assert( pFile );
+ /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
+ assert((flags&0x0F)==SQLITE_SYNC_NORMAL
+ || (flags&0x0F)==SQLITE_SYNC_FULL
+ );
+
+ /* Unix cannot, but some systems may return SQLITE_FULL from here. This
+ ** line is to test that doing so does not cause any problems.
+ */
+ SimulateDiskfullError( return SQLITE_FULL );
+
+ OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, flags=%x, lock=%d\n",
+ osGetCurrentProcessId(), pFile, pFile->h, flags,
+ pFile->locktype));
+
+#ifndef SQLITE_TEST
+ UNUSED_PARAMETER(flags);
+#else
+ if( (flags&0x0F)==SQLITE_SYNC_FULL ){
+ sqlite3_fullsync_count++;
+ }
+ sqlite3_sync_count++;
+#endif
+
+ /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
+ ** no-op
+ */
+#ifdef SQLITE_NO_SYNC
+ OSTRACE(("SYNC-NOP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return SQLITE_OK;
+#else
+#if SQLITE_MAX_MMAP_SIZE>0
+ if( pFile->pMapRegion ){
+ if( osFlushViewOfFile(pFile->pMapRegion, 0) ){
+ OSTRACE(("SYNC-MMAP pid=%lu, pFile=%p, pMapRegion=%p, "
+ "rc=SQLITE_OK\n", osGetCurrentProcessId(),
+ pFile, pFile->pMapRegion));
+ }else{
+ pFile->lastErrno = osGetLastError();
+ OSTRACE(("SYNC-MMAP pid=%lu, pFile=%p, pMapRegion=%p, "
+ "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(),
+ pFile, pFile->pMapRegion));
+ return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
+ "winSync1", pFile->zPath);
+ }
+ }
+#endif
+ rc = osFlushFileBuffers(pFile->h);
+ SimulateIOError( rc=FALSE );
+ if( rc ){
+ OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return SQLITE_OK;
+ }else{
+ pFile->lastErrno = osGetLastError();
+ OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_FSYNC\n",
+ osGetCurrentProcessId(), pFile, pFile->h));
+ return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
+ "winSync2", pFile->zPath);
+ }
+#endif
+}
+
+/*
+** Determine the current size of a file in bytes
+*/
+static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
+ winFile *pFile = (winFile*)id;
+ int rc = SQLITE_OK;
+
+ assert( id!=0 );
+ assert( pSize!=0 );
+ SimulateIOError(return SQLITE_IOERR_FSTAT);
+ OSTRACE(("SIZE file=%p, pSize=%p\n", pFile->h, pSize));
+
+#if SQLITE_OS_WINRT
+ {
+ FILE_STANDARD_INFO info;
+ if( osGetFileInformationByHandleEx(pFile->h, FileStandardInfo,
+ &info, sizeof(info)) ){
+ *pSize = info.EndOfFile.QuadPart;
+ }else{
+ pFile->lastErrno = osGetLastError();
+ rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
+ "winFileSize", pFile->zPath);
+ }
+ }
+#else
+ {
+ DWORD upperBits;
+ DWORD lowerBits;
+ DWORD lastErrno;
+
+ lowerBits = osGetFileSize(pFile->h, &upperBits);
+ *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
+ if( (lowerBits == INVALID_FILE_SIZE)
+ && ((lastErrno = osGetLastError())!=NO_ERROR) ){
+ pFile->lastErrno = lastErrno;
+ rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
+ "winFileSize", pFile->zPath);
+ }
+ }
+#endif
+ OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
+ pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
+*/
+#ifndef LOCKFILE_FAIL_IMMEDIATELY
+# define LOCKFILE_FAIL_IMMEDIATELY 1
+#endif
+
+#ifndef LOCKFILE_EXCLUSIVE_LOCK
+# define LOCKFILE_EXCLUSIVE_LOCK 2
+#endif
+
+/*
+** Historically, SQLite has used both the LockFile and LockFileEx functions.
+** When the LockFile function was used, it was always expected to fail
+** immediately if the lock could not be obtained. Also, it always expected to
+** obtain an exclusive lock. These flags are used with the LockFileEx function
+** and reflect those expectations; therefore, they should not be changed.
+*/
+#ifndef SQLITE_LOCKFILE_FLAGS
+# define SQLITE_LOCKFILE_FLAGS (LOCKFILE_FAIL_IMMEDIATELY | \
+ LOCKFILE_EXCLUSIVE_LOCK)
+#endif
+
+/*
+** Currently, SQLite never calls the LockFileEx function without wanting the
+** call to fail immediately if the lock cannot be obtained.
+*/
+#ifndef SQLITE_LOCKFILEEX_FLAGS
+# define SQLITE_LOCKFILEEX_FLAGS (LOCKFILE_FAIL_IMMEDIATELY)
+#endif
+
+/*
+** Acquire a reader lock.
+** Different API routines are called depending on whether or not this
+** is Win9x or WinNT.
+*/
+static int winGetReadLock(winFile *pFile){
+ int res;
+ OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
+ if( osIsNT() ){
+#if SQLITE_OS_WINCE
+ /*
+ ** NOTE: Windows CE is handled differently here due its lack of the Win32
+ ** API LockFileEx.
+ */
+ res = winceLockFile(&pFile->h, SHARED_FIRST, 0, 1, 0);
+#else
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS, SHARED_FIRST, 0,
+ SHARED_SIZE, 0);
+#endif
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ int lk;
+ sqlite3_randomness(sizeof(lk), &lk);
+ pFile->sharedLockByte = (short)((lk & 0x7fffffff)%(SHARED_SIZE - 1));
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
+ SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
+ }
+#endif
+ if( res == 0 ){
+ pFile->lastErrno = osGetLastError();
+ /* No need to log a failure to lock */
+ }
+ OSTRACE(("READ-LOCK file=%p, result=%d\n", pFile->h, res));
+ return res;
+}
+
+/*
+** Undo a readlock
+*/
+static int winUnlockReadLock(winFile *pFile){
+ int res;
+ DWORD lastErrno;
+ OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
+ if( osIsNT() ){
+ res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ res = winUnlockFile(&pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
+ }
+#endif
+ if( res==0 && ((lastErrno = osGetLastError())!=ERROR_NOT_LOCKED) ){
+ pFile->lastErrno = lastErrno;
+ winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
+ "winUnlockReadLock", pFile->zPath);
+ }
+ OSTRACE(("READ-UNLOCK file=%p, result=%d\n", pFile->h, res));
+ return res;
+}
+
+/*
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. The winUnlock() routine
+** erases all locks at once and returns us immediately to locking level 0.
+** It is not possible to lower the locking level one step at a time. You
+** must go straight to locking level 0.
+*/
+static int winLock(sqlite3_file *id, int locktype){
+ int rc = SQLITE_OK; /* Return code from subroutines */
+ int res = 1; /* Result of a Windows lock call */
+ int newLocktype; /* Set pFile->locktype to this value before exiting */
+ int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
+ winFile *pFile = (winFile*)id;
+ DWORD lastErrno = NO_ERROR;
+
+ assert( id!=0 );
+ OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
+ pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
+
+ /* If there is already a lock of this type or more restrictive on the
+ ** OsFile, do nothing. Don't use the end_lock: exit path, as
+ ** sqlite3OsEnterMutex() hasn't been called yet.
+ */
+ if( pFile->locktype>=locktype ){
+ OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+
+ /* Do not allow any kind of write-lock on a read-only database
+ */
+ if( (pFile->ctrlFlags & WINFILE_RDONLY)!=0 && locktype>=RESERVED_LOCK ){
+ return SQLITE_IOERR_LOCK;
+ }
+
+ /* Make sure the locking sequence is correct
+ */
+ assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
+ assert( locktype!=PENDING_LOCK );
+ assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
+
+ /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
+ ** a SHARED lock. If we are acquiring a SHARED lock, the acquisition of
+ ** the PENDING_LOCK byte is temporary.
+ */
+ newLocktype = pFile->locktype;
+ if( pFile->locktype==NO_LOCK
+ || (locktype==EXCLUSIVE_LOCK && pFile->locktype<=RESERVED_LOCK)
+ ){
+ int cnt = 3;
+ while( cnt-->0 && (res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
+ PENDING_BYTE, 0, 1, 0))==0 ){
+ /* Try 3 times to get the pending lock. This is needed to work
+ ** around problems caused by indexing and/or anti-virus software on
+ ** Windows systems.
+ ** If you are using this code as a model for alternative VFSes, do not
+ ** copy this retry logic. It is a hack intended for Windows only.
+ */
+ lastErrno = osGetLastError();
+ OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, result=%d\n",
+ pFile->h, cnt, res));
+ if( lastErrno==ERROR_INVALID_HANDLE ){
+ pFile->lastErrno = lastErrno;
+ rc = SQLITE_IOERR_LOCK;
+ OSTRACE(("LOCK-FAIL file=%p, count=%d, rc=%s\n",
+ pFile->h, cnt, sqlite3ErrName(rc)));
+ return rc;
+ }
+ if( cnt ) sqlite3_win32_sleep(1);
+ }
+ gotPendingLock = res;
+ if( !res ){
+ lastErrno = osGetLastError();
+ }
+ }
+
+ /* Acquire a shared lock
+ */
+ if( locktype==SHARED_LOCK && res ){
+ assert( pFile->locktype==NO_LOCK );
+ res = winGetReadLock(pFile);
+ if( res ){
+ newLocktype = SHARED_LOCK;
+ }else{
+ lastErrno = osGetLastError();
+ }
+ }
+
+ /* Acquire a RESERVED lock
+ */
+ if( locktype==RESERVED_LOCK && res ){
+ assert( pFile->locktype==SHARED_LOCK );
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, RESERVED_BYTE, 0, 1, 0);
+ if( res ){
+ newLocktype = RESERVED_LOCK;
+ }else{
+ lastErrno = osGetLastError();
+ }
+ }
+
+ /* Acquire a PENDING lock
+ */
+ if( locktype==EXCLUSIVE_LOCK && res ){
+ newLocktype = PENDING_LOCK;
+ gotPendingLock = 0;
+ }
+
+ /* Acquire an EXCLUSIVE lock
+ */
+ if( locktype==EXCLUSIVE_LOCK && res ){
+ assert( pFile->locktype>=SHARED_LOCK );
+ res = winUnlockReadLock(pFile);
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
+ SHARED_SIZE, 0);
+ if( res ){
+ newLocktype = EXCLUSIVE_LOCK;
+ }else{
+ lastErrno = osGetLastError();
+ winGetReadLock(pFile);
+ }
+ }
+
+ /* If we are holding a PENDING lock that ought to be released, then
+ ** release it now.
+ */
+ if( gotPendingLock && locktype==SHARED_LOCK ){
+ winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
+ }
+
+ /* Update the state of the lock has held in the file descriptor then
+ ** return the appropriate result code.
+ */
+ if( res ){
+ rc = SQLITE_OK;
+ }else{
+ pFile->lastErrno = lastErrno;
+ rc = SQLITE_BUSY;
+ OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
+ pFile->h, locktype, newLocktype));
+ }
+ pFile->locktype = (u8)newLocktype;
+ OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
+ pFile->h, pFile->locktype, sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, return
+** non-zero, otherwise zero.
+*/
+static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
+ int res;
+ winFile *pFile = (winFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+ OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));
+
+ assert( id!=0 );
+ if( pFile->locktype>=RESERVED_LOCK ){
+ res = 1;
+ OSTRACE(("TEST-WR-LOCK file=%p, result=%d (local)\n", pFile->h, res));
+ }else{
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE,0,1,0);
+ if( res ){
+ winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
+ }
+ res = !res;
+ OSTRACE(("TEST-WR-LOCK file=%p, result=%d (remote)\n", pFile->h, res));
+ }
+ *pResOut = res;
+ OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
+ pFile->h, pResOut, *pResOut));
+ return SQLITE_OK;
+}
+
+/*
+** Lower the locking level on file descriptor id to locktype. locktype
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+**
+** It is not possible for this routine to fail if the second argument
+** is NO_LOCK. If the second argument is SHARED_LOCK then this routine
+** might return SQLITE_IOERR;
+*/
+static int winUnlock(sqlite3_file *id, int locktype){
+ int type;
+ winFile *pFile = (winFile*)id;
+ int rc = SQLITE_OK;
+ assert( pFile!=0 );
+ assert( locktype<=SHARED_LOCK );
+ OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
+ pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
+ type = pFile->locktype;
+ if( type>=EXCLUSIVE_LOCK ){
+ winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
+ if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
+ /* This should never happen. We should always be able to
+ ** reacquire the read lock */
+ rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
+ "winUnlock", pFile->zPath);
+ }
+ }
+ if( type>=RESERVED_LOCK ){
+ winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
+ }
+ if( locktype==NO_LOCK && type>=SHARED_LOCK ){
+ winUnlockReadLock(pFile);
+ }
+ if( type>=PENDING_LOCK ){
+ winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
+ }
+ pFile->locktype = (u8)locktype;
+ OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
+ pFile->h, pFile->locktype, sqlite3ErrName(rc)));
+ return rc;
+}
+
+/******************************************************************************
+****************************** No-op Locking **********************************
+**
+** Of the various locking implementations available, this is by far the
+** simplest: locking is ignored. No attempt is made to lock the database
+** file for reading or writing.
+**
+** This locking mode is appropriate for use on read-only databases
+** (ex: databases that are burned into CD-ROM, for example.) It can
+** also be used if the application employs some external mechanism to
+** prevent simultaneous access of the same database by two or more
+** database connections. But there is a serious risk of database
+** corruption if this locking mode is used in situations where multiple
+** database connections are accessing the same database file at the same
+** time and one or more of those connections are writing.
+*/
+
+static int winNolockLock(sqlite3_file *id, int locktype){
+ UNUSED_PARAMETER(id);
+ UNUSED_PARAMETER(locktype);
+ return SQLITE_OK;
+}
+
+static int winNolockCheckReservedLock(sqlite3_file *id, int *pResOut){
+ UNUSED_PARAMETER(id);
+ UNUSED_PARAMETER(pResOut);
+ return SQLITE_OK;
+}
+
+static int winNolockUnlock(sqlite3_file *id, int locktype){
+ UNUSED_PARAMETER(id);
+ UNUSED_PARAMETER(locktype);
+ return SQLITE_OK;
+}
+
+/******************* End of the no-op lock implementation *********************
+******************************************************************************/
+
+/*
+** If *pArg is initially negative then this is a query. Set *pArg to
+** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
+**
+** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
+*/
+static void winModeBit(winFile *pFile, unsigned char mask, int *pArg){
+ if( *pArg<0 ){
+ *pArg = (pFile->ctrlFlags & mask)!=0;
+ }else if( (*pArg)==0 ){
+ pFile->ctrlFlags &= ~mask;
+ }else{
+ pFile->ctrlFlags |= mask;
+ }
+}
+
+/* Forward references to VFS helper methods used for temporary files */
+static int winGetTempname(sqlite3_vfs *, char **);
+static int winIsDir(const void *);
+static BOOL winIsDriveLetterAndColon(const char *);
+
+/*
+** Control and query of the open file handle.
+*/
+static int winFileControl(sqlite3_file *id, int op, void *pArg){
+ winFile *pFile = (winFile*)id;
+ OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
+ switch( op ){
+ case SQLITE_FCNTL_LOCKSTATE: {
+ *(int*)pArg = pFile->locktype;
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_LAST_ERRNO: {
+ *(int*)pArg = (int)pFile->lastErrno;
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_CHUNK_SIZE: {
+ pFile->szChunk = *(int *)pArg;
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_SIZE_HINT: {
+ if( pFile->szChunk>0 ){
+ sqlite3_int64 oldSz;
+ int rc = winFileSize(id, &oldSz);
+ if( rc==SQLITE_OK ){
+ sqlite3_int64 newSz = *(sqlite3_int64*)pArg;
+ if( newSz>oldSz ){
+ SimulateIOErrorBenign(1);
+ rc = winTruncate(id, newSz);
+ SimulateIOErrorBenign(0);
+ }
+ }
+ OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
+ return rc;
+ }
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_PERSIST_WAL: {
+ winModeBit(pFile, WINFILE_PERSIST_WAL, (int*)pArg);
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
+ winModeBit(pFile, WINFILE_PSOW, (int*)pArg);
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_VFSNAME: {
+ *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_WIN32_AV_RETRY: {
+ int *a = (int*)pArg;
+ if( a[0]>0 ){
+ winIoerrRetry = a[0];
+ }else{
+ a[0] = winIoerrRetry;
+ }
+ if( a[1]>0 ){
+ winIoerrRetryDelay = a[1];
+ }else{
+ a[1] = winIoerrRetryDelay;
+ }
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_WIN32_GET_HANDLE: {
+ LPHANDLE phFile = (LPHANDLE)pArg;
+ *phFile = pFile->h;
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+#ifdef SQLITE_TEST
+ case SQLITE_FCNTL_WIN32_SET_HANDLE: {
+ LPHANDLE phFile = (LPHANDLE)pArg;
+ HANDLE hOldFile = pFile->h;
+ pFile->h = *phFile;
+ *phFile = hOldFile;
+ OSTRACE(("FCNTL oldFile=%p, newFile=%p, rc=SQLITE_OK\n",
+ hOldFile, pFile->h));
+ return SQLITE_OK;
+ }
+#endif
+ case SQLITE_FCNTL_TEMPFILENAME: {
+ char *zTFile = 0;
+ int rc = winGetTempname(pFile->pVfs, &zTFile);
+ if( rc==SQLITE_OK ){
+ *(char**)pArg = zTFile;
+ }
+ OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
+ return rc;
+ }
+#if SQLITE_MAX_MMAP_SIZE>0
+ case SQLITE_FCNTL_MMAP_SIZE: {
+ i64 newLimit = *(i64*)pArg;
+ int rc = SQLITE_OK;
+ if( newLimit>sqlite3GlobalConfig.mxMmap ){
+ newLimit = sqlite3GlobalConfig.mxMmap;
+ }
+
+ /* The value of newLimit may be eventually cast to (SIZE_T) and passed
+ ** to MapViewOfFile(). Restrict its value to 2GB if (SIZE_T) is not at
+ ** least a 64-bit type. */
+ if( newLimit>0 && sizeof(SIZE_T)<8 ){
+ newLimit = (newLimit & 0x7FFFFFFF);
+ }
+
+ *(i64*)pArg = pFile->mmapSizeMax;
+ if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
+ pFile->mmapSizeMax = newLimit;
+ if( pFile->mmapSize>0 ){
+ winUnmapfile(pFile);
+ rc = winMapfile(pFile, -1);
+ }
+ }
+ OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
+ return rc;
+ }
+#endif
+ }
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
+ return SQLITE_NOTFOUND;
+}
+
+/*
+** Return the sector size in bytes of the underlying block device for
+** the specified file. This is almost always 512 bytes, but may be
+** larger for some devices.
+**
+** SQLite code assumes this function cannot fail. It also assumes that
+** if two files are created in the same file-system directory (i.e.
+** a database and its journal file) that the sector size will be the
+** same for both.
+*/
+static int winSectorSize(sqlite3_file *id){
+ (void)id;
+ return SQLITE_DEFAULT_SECTOR_SIZE;
+}
+
+/*
+** Return a vector of device characteristics.
+*/
+static int winDeviceCharacteristics(sqlite3_file *id){
+ winFile *p = (winFile*)id;
+ return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
+ ((p->ctrlFlags & WINFILE_PSOW)?SQLITE_IOCAP_POWERSAFE_OVERWRITE:0);
+}
+
+/*
+** Windows will only let you create file view mappings
+** on allocation size granularity boundaries.
+** During sqlite3_os_init() we do a GetSystemInfo()
+** to get the granularity size.
+*/
+static SYSTEM_INFO winSysInfo;
+
+#ifndef SQLITE_OMIT_WAL
+
+/*
+** Helper functions to obtain and relinquish the global mutex. The
+** global mutex is used to protect the winLockInfo objects used by
+** this file, all of which may be shared by multiple threads.
+**
+** Function winShmMutexHeld() is used to assert() that the global mutex
+** is held when required. This function is only used as part of assert()
+** statements. e.g.
+**
+** winShmEnterMutex()
+** assert( winShmMutexHeld() );
+** winShmLeaveMutex()
+*/
+static sqlite3_mutex *winBigLock = 0;
+static void winShmEnterMutex(void){
+ sqlite3_mutex_enter(winBigLock);
+}
+static void winShmLeaveMutex(void){
+ sqlite3_mutex_leave(winBigLock);
+}
+#ifndef NDEBUG
+static int winShmMutexHeld(void) {
+ return sqlite3_mutex_held(winBigLock);
+}
+#endif
+
+/*
+** Object used to represent a single file opened and mmapped to provide
+** shared memory. When multiple threads all reference the same
+** log-summary, each thread has its own winFile object, but they all
+** point to a single instance of this object. In other words, each
+** log-summary is opened only once per process.
+**
+** winShmMutexHeld() must be true when creating or destroying
+** this object or while reading or writing the following fields:
+**
+** nRef
+** pNext
+**
+** The following fields are read-only after the object is created:
+**
+** fid
+** zFilename
+**
+** Either winShmNode.mutex must be held or winShmNode.nRef==0 and
+** winShmMutexHeld() is true when reading or writing any other field
+** in this structure.
+**
+*/
+struct winShmNode {
+ sqlite3_mutex *mutex; /* Mutex to access this object */
+ char *zFilename; /* Name of the file */
+ winFile hFile; /* File handle from winOpen */
+
+ int szRegion; /* Size of shared-memory regions */
+ int nRegion; /* Size of array apRegion */
+ u8 isReadonly; /* True if read-only */
+ u8 isUnlocked; /* True if no DMS lock held */
+
+ struct ShmRegion {
+ HANDLE hMap; /* File handle from CreateFileMapping */
+ void *pMap;
+ } *aRegion;
+ DWORD lastErrno; /* The Windows errno from the last I/O error */
+
+ int nRef; /* Number of winShm objects pointing to this */
+ winShm *pFirst; /* All winShm objects pointing to this */
+ winShmNode *pNext; /* Next in list of all winShmNode objects */
+#if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
+ u8 nextShmId; /* Next available winShm.id value */
+#endif
+};
+
+/*
+** A global array of all winShmNode objects.
+**
+** The winShmMutexHeld() must be true while reading or writing this list.
+*/
+static winShmNode *winShmNodeList = 0;
+
+/*
+** Structure used internally by this VFS to record the state of an
+** open shared memory connection.
+**
+** The following fields are initialized when this object is created and
+** are read-only thereafter:
+**
+** winShm.pShmNode
+** winShm.id
+**
+** All other fields are read/write. The winShm.pShmNode->mutex must be held
+** while accessing any read/write fields.
+*/
+struct winShm {
+ winShmNode *pShmNode; /* The underlying winShmNode object */
+ winShm *pNext; /* Next winShm with the same winShmNode */
+ u8 hasMutex; /* True if holding the winShmNode mutex */
+ u16 sharedMask; /* Mask of shared locks held */
+ u16 exclMask; /* Mask of exclusive locks held */
+#if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
+ u8 id; /* Id of this connection with its winShmNode */
+#endif
+};
+
+/*
+** Constants used for locking
+*/
+#define WIN_SHM_BASE ((22+SQLITE_SHM_NLOCK)*4) /* first lock byte */
+#define WIN_SHM_DMS (WIN_SHM_BASE+SQLITE_SHM_NLOCK) /* deadman switch */
+
+/*
+** Apply advisory locks for all n bytes beginning at ofst.
+*/
+#define WINSHM_UNLCK 1
+#define WINSHM_RDLCK 2
+#define WINSHM_WRLCK 3
+static int winShmSystemLock(
+ winShmNode *pFile, /* Apply locks to this open shared-memory segment */
+ int lockType, /* WINSHM_UNLCK, WINSHM_RDLCK, or WINSHM_WRLCK */
+ int ofst, /* Offset to first byte to be locked/unlocked */
+ int nByte /* Number of bytes to lock or unlock */
+){
+ int rc = 0; /* Result code form Lock/UnlockFileEx() */
+
+ /* Access to the winShmNode object is serialized by the caller */
+ assert( pFile->nRef==0 || sqlite3_mutex_held(pFile->mutex) );
+
+ OSTRACE(("SHM-LOCK file=%p, lock=%d, offset=%d, size=%d\n",
+ pFile->hFile.h, lockType, ofst, nByte));
+
+ /* Release/Acquire the system-level lock */
+ if( lockType==WINSHM_UNLCK ){
+ rc = winUnlockFile(&pFile->hFile.h, ofst, 0, nByte, 0);
+ }else{
+ /* Initialize the locking parameters */
+ DWORD dwFlags = LOCKFILE_FAIL_IMMEDIATELY;
+ if( lockType == WINSHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK;
+ rc = winLockFile(&pFile->hFile.h, dwFlags, ofst, 0, nByte, 0);
+ }
+
+ if( rc!= 0 ){
+ rc = SQLITE_OK;
+ }else{
+ pFile->lastErrno = osGetLastError();
+ rc = SQLITE_BUSY;
+ }
+
+ OSTRACE(("SHM-LOCK file=%p, func=%s, errno=%lu, rc=%s\n",
+ pFile->hFile.h, (lockType == WINSHM_UNLCK) ? "winUnlockFile" :
+ "winLockFile", pFile->lastErrno, sqlite3ErrName(rc)));
+
+ return rc;
+}
+
+/* Forward references to VFS methods */
+static int winOpen(sqlite3_vfs*,const char*,sqlite3_file*,int,int*);
+static int winDelete(sqlite3_vfs *,const char*,int);
+
+/*
+** Purge the winShmNodeList list of all entries with winShmNode.nRef==0.
+**
+** This is not a VFS shared-memory method; it is a utility function called
+** by VFS shared-memory methods.
+*/
+static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
+ winShmNode **pp;
+ winShmNode *p;
+ assert( winShmMutexHeld() );
+ OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
+ osGetCurrentProcessId(), deleteFlag));
+ pp = &winShmNodeList;
+ while( (p = *pp)!=0 ){
+ if( p->nRef==0 ){
+ int i;
+ if( p->mutex ){ sqlite3_mutex_free(p->mutex); }
+ for(i=0; inRegion; i++){
+ BOOL bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
+ OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
+ osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
+ UNUSED_VARIABLE_VALUE(bRc);
+ bRc = osCloseHandle(p->aRegion[i].hMap);
+ OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
+ osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
+ UNUSED_VARIABLE_VALUE(bRc);
+ }
+ if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
+ SimulateIOErrorBenign(1);
+ winClose((sqlite3_file *)&p->hFile);
+ SimulateIOErrorBenign(0);
+ }
+ if( deleteFlag ){
+ SimulateIOErrorBenign(1);
+ sqlite3BeginBenignMalloc();
+ winDelete(pVfs, p->zFilename, 0);
+ sqlite3EndBenignMalloc();
+ SimulateIOErrorBenign(0);
+ }
+ *pp = p->pNext;
+ sqlite3_free(p->aRegion);
+ sqlite3_free(p);
+ }else{
+ pp = &p->pNext;
+ }
+ }
+}
+
+/*
+** The DMS lock has not yet been taken on shm file pShmNode. Attempt to
+** take it now. Return SQLITE_OK if successful, or an SQLite error
+** code otherwise.
+**
+** If the DMS cannot be locked because this is a readonly_shm=1
+** connection and no other process already holds a lock, return
+** SQLITE_READONLY_CANTINIT and set pShmNode->isUnlocked=1.
+*/
+static int winLockSharedMemory(winShmNode *pShmNode){
+ int rc = winShmSystemLock(pShmNode, WINSHM_WRLCK, WIN_SHM_DMS, 1);
+
+ if( rc==SQLITE_OK ){
+ if( pShmNode->isReadonly ){
+ pShmNode->isUnlocked = 1;
+ winShmSystemLock(pShmNode, WINSHM_UNLCK, WIN_SHM_DMS, 1);
+ return SQLITE_READONLY_CANTINIT;
+ }else if( winTruncate((sqlite3_file*)&pShmNode->hFile, 0) ){
+ winShmSystemLock(pShmNode, WINSHM_UNLCK, WIN_SHM_DMS, 1);
+ return winLogError(SQLITE_IOERR_SHMOPEN, osGetLastError(),
+ "winLockSharedMemory", pShmNode->zFilename);
+ }
+ }
+
+ if( rc==SQLITE_OK ){
+ winShmSystemLock(pShmNode, WINSHM_UNLCK, WIN_SHM_DMS, 1);
+ }
+
+ return winShmSystemLock(pShmNode, WINSHM_RDLCK, WIN_SHM_DMS, 1);
+}
+
+/*
+** Open the shared-memory area associated with database file pDbFd.
+**
+** When opening a new shared-memory file, if no other instances of that
+** file are currently open, in this process or in other processes, then
+** the file must be truncated to zero length or have its header cleared.
+*/
+static int winOpenSharedMemory(winFile *pDbFd){
+ struct winShm *p; /* The connection to be opened */
+ winShmNode *pShmNode = 0; /* The underlying mmapped file */
+ int rc = SQLITE_OK; /* Result code */
+ winShmNode *pNew; /* Newly allocated winShmNode */
+ int nName; /* Size of zName in bytes */
+
+ assert( pDbFd->pShm==0 ); /* Not previously opened */
+
+ /* Allocate space for the new sqlite3_shm object. Also speculatively
+ ** allocate space for a new winShmNode and filename.
+ */
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p==0 ) return SQLITE_IOERR_NOMEM_BKPT;
+ nName = sqlite3Strlen30(pDbFd->zPath);
+ pNew = sqlite3MallocZero( sizeof(*pShmNode) + nName + 17 );
+ if( pNew==0 ){
+ sqlite3_free(p);
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ pNew->zFilename = (char*)&pNew[1];
+ sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath);
+ sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename);
+
+ /* Look to see if there is an existing winShmNode that can be used.
+ ** If no matching winShmNode currently exists, create a new one.
+ */
+ winShmEnterMutex();
+ for(pShmNode = winShmNodeList; pShmNode; pShmNode=pShmNode->pNext){
+ /* TBD need to come up with better match here. Perhaps
+ ** use FILE_ID_BOTH_DIR_INFO Structure.
+ */
+ if( sqlite3StrICmp(pShmNode->zFilename, pNew->zFilename)==0 ) break;
+ }
+ if( pShmNode ){
+ sqlite3_free(pNew);
+ }else{
+ int inFlags = SQLITE_OPEN_WAL;
+ int outFlags = 0;
+
+ pShmNode = pNew;
+ pNew = 0;
+ ((winFile*)(&pShmNode->hFile))->h = INVALID_HANDLE_VALUE;
+ pShmNode->pNext = winShmNodeList;
+ winShmNodeList = pShmNode;
+
+ if( sqlite3GlobalConfig.bCoreMutex ){
+ pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
+ if( pShmNode->mutex==0 ){
+ rc = SQLITE_IOERR_NOMEM_BKPT;
+ goto shm_open_err;
+ }
+ }
+
+ if( 0==sqlite3_uri_boolean(pDbFd->zPath, "readonly_shm", 0) ){
+ inFlags |= SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE;
+ }else{
+ inFlags |= SQLITE_OPEN_READONLY;
+ }
+ rc = winOpen(pDbFd->pVfs, pShmNode->zFilename,
+ (sqlite3_file*)&pShmNode->hFile,
+ inFlags, &outFlags);
+ if( rc!=SQLITE_OK ){
+ rc = winLogError(rc, osGetLastError(), "winOpenShm",
+ pShmNode->zFilename);
+ goto shm_open_err;
+ }
+ if( outFlags==SQLITE_OPEN_READONLY ) pShmNode->isReadonly = 1;
+
+ rc = winLockSharedMemory(pShmNode);
+ if( rc!=SQLITE_OK && rc!=SQLITE_READONLY_CANTINIT ) goto shm_open_err;
+ }
+
+ /* Make the new connection a child of the winShmNode */
+ p->pShmNode = pShmNode;
+#if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
+ p->id = pShmNode->nextShmId++;
+#endif
+ pShmNode->nRef++;
+ pDbFd->pShm = p;
+ winShmLeaveMutex();
+
+ /* The reference count on pShmNode has already been incremented under
+ ** the cover of the winShmEnterMutex() mutex and the pointer from the
+ ** new (struct winShm) object to the pShmNode has been set. All that is
+ ** left to do is to link the new object into the linked list starting
+ ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex
+ ** mutex.
+ */
+ sqlite3_mutex_enter(pShmNode->mutex);
+ p->pNext = pShmNode->pFirst;
+ pShmNode->pFirst = p;
+ sqlite3_mutex_leave(pShmNode->mutex);
+ return rc;
+
+ /* Jump here on any error */
+shm_open_err:
+ winShmSystemLock(pShmNode, WINSHM_UNLCK, WIN_SHM_DMS, 1);
+ winShmPurge(pDbFd->pVfs, 0); /* This call frees pShmNode if required */
+ sqlite3_free(p);
+ sqlite3_free(pNew);
+ winShmLeaveMutex();
+ return rc;
+}
+
+/*
+** Close a connection to shared-memory. Delete the underlying
+** storage if deleteFlag is true.
+*/
+static int winShmUnmap(
+ sqlite3_file *fd, /* Database holding shared memory */
+ int deleteFlag /* Delete after closing if true */
+){
+ winFile *pDbFd; /* Database holding shared-memory */
+ winShm *p; /* The connection to be closed */
+ winShmNode *pShmNode; /* The underlying shared-memory file */
+ winShm **pp; /* For looping over sibling connections */
+
+ pDbFd = (winFile*)fd;
+ p = pDbFd->pShm;
+ if( p==0 ) return SQLITE_OK;
+ pShmNode = p->pShmNode;
+
+ /* Remove connection p from the set of connections associated
+ ** with pShmNode */
+ sqlite3_mutex_enter(pShmNode->mutex);
+ for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
+ *pp = p->pNext;
+
+ /* Free the connection p */
+ sqlite3_free(p);
+ pDbFd->pShm = 0;
+ sqlite3_mutex_leave(pShmNode->mutex);
+
+ /* If pShmNode->nRef has reached 0, then close the underlying
+ ** shared-memory file, too */
+ winShmEnterMutex();
+ assert( pShmNode->nRef>0 );
+ pShmNode->nRef--;
+ if( pShmNode->nRef==0 ){
+ winShmPurge(pDbFd->pVfs, deleteFlag);
+ }
+ winShmLeaveMutex();
+
+ return SQLITE_OK;
+}
+
+/*
+** Change the lock state for a shared-memory segment.
+*/
+static int winShmLock(
+ sqlite3_file *fd, /* Database file holding the shared memory */
+ int ofst, /* First lock to acquire or release */
+ int n, /* Number of locks to acquire or release */
+ int flags /* What to do with the lock */
+){
+ winFile *pDbFd = (winFile*)fd; /* Connection holding shared memory */
+ winShm *p = pDbFd->pShm; /* The shared memory being locked */
+ winShm *pX; /* For looping over all siblings */
+ winShmNode *pShmNode = p->pShmNode;
+ int rc = SQLITE_OK; /* Result code */
+ u16 mask; /* Mask of locks to take or release */
+
+ assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
+ assert( n>=1 );
+ assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
+ assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
+
+ mask = (u16)((1U<<(ofst+n)) - (1U<1 || mask==(1<mutex);
+ if( flags & SQLITE_SHM_UNLOCK ){
+ u16 allMask = 0; /* Mask of locks held by siblings */
+
+ /* See if any siblings hold this same lock */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( pX==p ) continue;
+ assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
+ allMask |= pX->sharedMask;
+ }
+
+ /* Unlock the system-level locks */
+ if( (mask & allMask)==0 ){
+ rc = winShmSystemLock(pShmNode, WINSHM_UNLCK, ofst+WIN_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+
+ /* Undo the local locks */
+ if( rc==SQLITE_OK ){
+ p->exclMask &= ~mask;
+ p->sharedMask &= ~mask;
+ }
+ }else if( flags & SQLITE_SHM_SHARED ){
+ u16 allShared = 0; /* Union of locks held by connections other than "p" */
+
+ /* Find out which shared locks are already held by sibling connections.
+ ** If any sibling already holds an exclusive lock, go ahead and return
+ ** SQLITE_BUSY.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ allShared |= pX->sharedMask;
+ }
+
+ /* Get shared locks at the system level, if necessary */
+ if( rc==SQLITE_OK ){
+ if( (allShared & mask)==0 ){
+ rc = winShmSystemLock(pShmNode, WINSHM_RDLCK, ofst+WIN_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+ }
+
+ /* Get the local shared locks */
+ if( rc==SQLITE_OK ){
+ p->sharedMask |= mask;
+ }
+ }else{
+ /* Make sure no sibling connections hold locks that will block this
+ ** lock. If any do, return SQLITE_BUSY right away.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ }
+
+ /* Get the exclusive locks at the system level. Then if successful
+ ** also mark the local connection as being locked.
+ */
+ if( rc==SQLITE_OK ){
+ rc = winShmSystemLock(pShmNode, WINSHM_WRLCK, ofst+WIN_SHM_BASE, n);
+ if( rc==SQLITE_OK ){
+ assert( (p->sharedMask & mask)==0 );
+ p->exclMask |= mask;
+ }
+ }
+ }
+ sqlite3_mutex_leave(pShmNode->mutex);
+ OSTRACE(("SHM-LOCK pid=%lu, id=%d, sharedMask=%03x, exclMask=%03x, rc=%s\n",
+ osGetCurrentProcessId(), p->id, p->sharedMask, p->exclMask,
+ sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** Implement a memory barrier or memory fence on shared memory.
+**
+** All loads and stores begun before the barrier must complete before
+** any load or store begun after the barrier.
+*/
+static void winShmBarrier(
+ sqlite3_file *fd /* Database holding the shared memory */
+){
+ UNUSED_PARAMETER(fd);
+ sqlite3MemoryBarrier(); /* compiler-defined memory barrier */
+ winShmEnterMutex(); /* Also mutex, for redundancy */
+ winShmLeaveMutex();
+}
+
+/*
+** This function is called to obtain a pointer to region iRegion of the
+** shared-memory associated with the database file fd. Shared-memory regions
+** are numbered starting from zero. Each shared-memory region is szRegion
+** bytes in size.
+**
+** If an error occurs, an error code is returned and *pp is set to NULL.
+**
+** Otherwise, if the isWrite parameter is 0 and the requested shared-memory
+** region has not been allocated (by any client, including one running in a
+** separate process), then *pp is set to NULL and SQLITE_OK returned. If
+** isWrite is non-zero and the requested shared-memory region has not yet
+** been allocated, it is allocated by this function.
+**
+** If the shared-memory region has already been allocated or is allocated by
+** this call as described above, then it is mapped into this processes
+** address space (if it is not already), *pp is set to point to the mapped
+** memory and SQLITE_OK returned.
+*/
+static int winShmMap(
+ sqlite3_file *fd, /* Handle open on database file */
+ int iRegion, /* Region to retrieve */
+ int szRegion, /* Size of regions */
+ int isWrite, /* True to extend file if necessary */
+ void volatile **pp /* OUT: Mapped memory */
+){
+ winFile *pDbFd = (winFile*)fd;
+ winShm *pShm = pDbFd->pShm;
+ winShmNode *pShmNode;
+ DWORD protect = PAGE_READWRITE;
+ DWORD flags = FILE_MAP_WRITE | FILE_MAP_READ;
+ int rc = SQLITE_OK;
+
+ if( !pShm ){
+ rc = winOpenSharedMemory(pDbFd);
+ if( rc!=SQLITE_OK ) return rc;
+ pShm = pDbFd->pShm;
+ }
+ pShmNode = pShm->pShmNode;
+
+ sqlite3_mutex_enter(pShmNode->mutex);
+ if( pShmNode->isUnlocked ){
+ rc = winLockSharedMemory(pShmNode);
+ if( rc!=SQLITE_OK ) goto shmpage_out;
+ pShmNode->isUnlocked = 0;
+ }
+ assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
+
+ if( pShmNode->nRegion<=iRegion ){
+ struct ShmRegion *apNew; /* New aRegion[] array */
+ int nByte = (iRegion+1)*szRegion; /* Minimum required file size */
+ sqlite3_int64 sz; /* Current size of wal-index file */
+
+ pShmNode->szRegion = szRegion;
+
+ /* The requested region is not mapped into this processes address space.
+ ** Check to see if it has been allocated (i.e. if the wal-index file is
+ ** large enough to contain the requested region).
+ */
+ rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
+ if( rc!=SQLITE_OK ){
+ rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
+ "winShmMap1", pDbFd->zPath);
+ goto shmpage_out;
+ }
+
+ if( szhFile, nByte);
+ if( rc!=SQLITE_OK ){
+ rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
+ "winShmMap2", pDbFd->zPath);
+ goto shmpage_out;
+ }
+ }
+
+ /* Map the requested memory region into this processes address space. */
+ apNew = (struct ShmRegion *)sqlite3_realloc64(
+ pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0])
+ );
+ if( !apNew ){
+ rc = SQLITE_IOERR_NOMEM_BKPT;
+ goto shmpage_out;
+ }
+ pShmNode->aRegion = apNew;
+
+ if( pShmNode->isReadonly ){
+ protect = PAGE_READONLY;
+ flags = FILE_MAP_READ;
+ }
+
+ while( pShmNode->nRegion<=iRegion ){
+ HANDLE hMap = NULL; /* file-mapping handle */
+ void *pMap = 0; /* Mapped memory region */
+
+#if SQLITE_OS_WINRT
+ hMap = osCreateFileMappingFromApp(pShmNode->hFile.h,
+ NULL, protect, nByte, NULL
+ );
+#elif defined(SQLITE_WIN32_HAS_WIDE)
+ hMap = osCreateFileMappingW(pShmNode->hFile.h,
+ NULL, protect, 0, nByte, NULL
+ );
+#elif defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_CREATEFILEMAPPINGA
+ hMap = osCreateFileMappingA(pShmNode->hFile.h,
+ NULL, protect, 0, nByte, NULL
+ );
+#endif
+ OSTRACE(("SHM-MAP-CREATE pid=%lu, region=%d, size=%d, rc=%s\n",
+ osGetCurrentProcessId(), pShmNode->nRegion, nByte,
+ hMap ? "ok" : "failed"));
+ if( hMap ){
+ int iOffset = pShmNode->nRegion*szRegion;
+ int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
+#if SQLITE_OS_WINRT
+ pMap = osMapViewOfFileFromApp(hMap, flags,
+ iOffset - iOffsetShift, szRegion + iOffsetShift
+ );
+#else
+ pMap = osMapViewOfFile(hMap, flags,
+ 0, iOffset - iOffsetShift, szRegion + iOffsetShift
+ );
+#endif
+ OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
+ osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
+ szRegion, pMap ? "ok" : "failed"));
+ }
+ if( !pMap ){
+ pShmNode->lastErrno = osGetLastError();
+ rc = winLogError(SQLITE_IOERR_SHMMAP, pShmNode->lastErrno,
+ "winShmMap3", pDbFd->zPath);
+ if( hMap ) osCloseHandle(hMap);
+ goto shmpage_out;
+ }
+
+ pShmNode->aRegion[pShmNode->nRegion].pMap = pMap;
+ pShmNode->aRegion[pShmNode->nRegion].hMap = hMap;
+ pShmNode->nRegion++;
+ }
+ }
+
+shmpage_out:
+ if( pShmNode->nRegion>iRegion ){
+ int iOffset = iRegion*szRegion;
+ int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
+ char *p = (char *)pShmNode->aRegion[iRegion].pMap;
+ *pp = (void *)&p[iOffsetShift];
+ }else{
+ *pp = 0;
+ }
+ if( pShmNode->isReadonly && rc==SQLITE_OK ) rc = SQLITE_READONLY;
+ sqlite3_mutex_leave(pShmNode->mutex);
+ return rc;
+}
+
+#else
+# define winShmMap 0
+# define winShmLock 0
+# define winShmBarrier 0
+# define winShmUnmap 0
+#endif /* #ifndef SQLITE_OMIT_WAL */
+
+/*
+** Cleans up the mapped region of the specified file, if any.
+*/
+#if SQLITE_MAX_MMAP_SIZE>0
+static int winUnmapfile(winFile *pFile){
+ assert( pFile!=0 );
+ OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, pMapRegion=%p, "
+ "mmapSize=%lld, mmapSizeActual=%lld, mmapSizeMax=%lld\n",
+ osGetCurrentProcessId(), pFile, pFile->hMap, pFile->pMapRegion,
+ pFile->mmapSize, pFile->mmapSizeActual, pFile->mmapSizeMax));
+ if( pFile->pMapRegion ){
+ if( !osUnmapViewOfFile(pFile->pMapRegion) ){
+ pFile->lastErrno = osGetLastError();
+ OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
+ "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
+ pFile->pMapRegion));
+ return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
+ "winUnmapfile1", pFile->zPath);
+ }
+ pFile->pMapRegion = 0;
+ pFile->mmapSize = 0;
+ pFile->mmapSizeActual = 0;
+ }
+ if( pFile->hMap!=NULL ){
+ if( !osCloseHandle(pFile->hMap) ){
+ pFile->lastErrno = osGetLastError();
+ OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
+ osGetCurrentProcessId(), pFile, pFile->hMap));
+ return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
+ "winUnmapfile2", pFile->zPath);
+ }
+ pFile->hMap = NULL;
+ }
+ OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFile));
+ return SQLITE_OK;
+}
+
+/*
+** Memory map or remap the file opened by file-descriptor pFd (if the file
+** is already mapped, the existing mapping is replaced by the new). Or, if
+** there already exists a mapping for this file, and there are still
+** outstanding xFetch() references to it, this function is a no-op.
+**
+** If parameter nByte is non-negative, then it is the requested size of
+** the mapping to create. Otherwise, if nByte is less than zero, then the
+** requested size is the size of the file on disk. The actual size of the
+** created mapping is either the requested size or the value configured
+** using SQLITE_FCNTL_MMAP_SIZE, whichever is smaller.
+**
+** SQLITE_OK is returned if no error occurs (even if the mapping is not
+** recreated as a result of outstanding references) or an SQLite error
+** code otherwise.
+*/
+static int winMapfile(winFile *pFd, sqlite3_int64 nByte){
+ sqlite3_int64 nMap = nByte;
+ int rc;
+
+ assert( nMap>=0 || pFd->nFetchOut==0 );
+ OSTRACE(("MAP-FILE pid=%lu, pFile=%p, size=%lld\n",
+ osGetCurrentProcessId(), pFd, nByte));
+
+ if( pFd->nFetchOut>0 ) return SQLITE_OK;
+
+ if( nMap<0 ){
+ rc = winFileSize((sqlite3_file*)pFd, &nMap);
+ if( rc ){
+ OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_IOERR_FSTAT\n",
+ osGetCurrentProcessId(), pFd));
+ return SQLITE_IOERR_FSTAT;
+ }
+ }
+ if( nMap>pFd->mmapSizeMax ){
+ nMap = pFd->mmapSizeMax;
+ }
+ nMap &= ~(sqlite3_int64)(winSysInfo.dwPageSize - 1);
+
+ if( nMap==0 && pFd->mmapSize>0 ){
+ winUnmapfile(pFd);
+ }
+ if( nMap!=pFd->mmapSize ){
+ void *pNew = 0;
+ DWORD protect = PAGE_READONLY;
+ DWORD flags = FILE_MAP_READ;
+
+ winUnmapfile(pFd);
+#ifdef SQLITE_MMAP_READWRITE
+ if( (pFd->ctrlFlags & WINFILE_RDONLY)==0 ){
+ protect = PAGE_READWRITE;
+ flags |= FILE_MAP_WRITE;
+ }
+#endif
+#if SQLITE_OS_WINRT
+ pFd->hMap = osCreateFileMappingFromApp(pFd->h, NULL, protect, nMap, NULL);
+#elif defined(SQLITE_WIN32_HAS_WIDE)
+ pFd->hMap = osCreateFileMappingW(pFd->h, NULL, protect,
+ (DWORD)((nMap>>32) & 0xffffffff),
+ (DWORD)(nMap & 0xffffffff), NULL);
+#elif defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_CREATEFILEMAPPINGA
+ pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
+ (DWORD)((nMap>>32) & 0xffffffff),
+ (DWORD)(nMap & 0xffffffff), NULL);
+#endif
+ if( pFd->hMap==NULL ){
+ pFd->lastErrno = osGetLastError();
+ rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
+ "winMapfile1", pFd->zPath);
+ /* Log the error, but continue normal operation using xRead/xWrite */
+ OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=%s\n",
+ osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
+ return SQLITE_OK;
+ }
+ assert( (nMap % winSysInfo.dwPageSize)==0 );
+ assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
+#if SQLITE_OS_WINRT
+ pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
+#else
+ pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
+#endif
+ if( pNew==NULL ){
+ osCloseHandle(pFd->hMap);
+ pFd->hMap = NULL;
+ pFd->lastErrno = osGetLastError();
+ rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
+ "winMapfile2", pFd->zPath);
+ /* Log the error, but continue normal operation using xRead/xWrite */
+ OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=%s\n",
+ osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
+ return SQLITE_OK;
+ }
+ pFd->pMapRegion = pNew;
+ pFd->mmapSize = nMap;
+ pFd->mmapSizeActual = nMap;
+ }
+
+ OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFd));
+ return SQLITE_OK;
+}
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
+
+/*
+** If possible, return a pointer to a mapping of file fd starting at offset
+** iOff. The mapping must be valid for at least nAmt bytes.
+**
+** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
+** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
+** Finally, if an error does occur, return an SQLite error code. The final
+** value of *pp is undefined in this case.
+**
+** If this function does return a pointer, the caller must eventually
+** release the reference by calling winUnfetch().
+*/
+static int winFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
+#if SQLITE_MAX_MMAP_SIZE>0
+ winFile *pFd = (winFile*)fd; /* The underlying database file */
+#endif
+ *pp = 0;
+
+ OSTRACE(("FETCH pid=%lu, pFile=%p, offset=%lld, amount=%d, pp=%p\n",
+ osGetCurrentProcessId(), fd, iOff, nAmt, pp));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ if( pFd->mmapSizeMax>0 ){
+ if( pFd->pMapRegion==0 ){
+ int rc = winMapfile(pFd, -1);
+ if( rc!=SQLITE_OK ){
+ OSTRACE(("FETCH pid=%lu, pFile=%p, rc=%s\n",
+ osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
+ return rc;
+ }
+ }
+ if( pFd->mmapSize >= iOff+nAmt ){
+ *pp = &((u8 *)pFd->pMapRegion)[iOff];
+ pFd->nFetchOut++;
+ }
+ }
+#endif
+
+ OSTRACE(("FETCH pid=%lu, pFile=%p, pp=%p, *pp=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), fd, pp, *pp));
+ return SQLITE_OK;
+}
+
+/*
+** If the third argument is non-NULL, then this function releases a
+** reference obtained by an earlier call to winFetch(). The second
+** argument passed to this function must be the same as the corresponding
+** argument that was passed to the winFetch() invocation.
+**
+** Or, if the third argument is NULL, then this function is being called
+** to inform the VFS layer that, according to POSIX, any existing mapping
+** may now be invalid and should be unmapped.
+*/
+static int winUnfetch(sqlite3_file *fd, i64 iOff, void *p){
+#if SQLITE_MAX_MMAP_SIZE>0
+ winFile *pFd = (winFile*)fd; /* The underlying database file */
+
+ /* If p==0 (unmap the entire file) then there must be no outstanding
+ ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
+ ** then there must be at least one outstanding. */
+ assert( (p==0)==(pFd->nFetchOut==0) );
+
+ /* If p!=0, it must match the iOff value. */
+ assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
+
+ OSTRACE(("UNFETCH pid=%lu, pFile=%p, offset=%lld, p=%p\n",
+ osGetCurrentProcessId(), pFd, iOff, p));
+
+ if( p ){
+ pFd->nFetchOut--;
+ }else{
+ /* FIXME: If Windows truly always prevents truncating or deleting a
+ ** file while a mapping is held, then the following winUnmapfile() call
+ ** is unnecessary can be omitted - potentially improving
+ ** performance. */
+ winUnmapfile(pFd);
+ }
+
+ assert( pFd->nFetchOut>=0 );
+#endif
+
+ OSTRACE(("UNFETCH pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), fd));
+ return SQLITE_OK;
+}
+
+/*
+** Here ends the implementation of all sqlite3_file methods.
+**
+********************** End sqlite3_file Methods *******************************
+******************************************************************************/
+
+/*
+** This vector defines all the methods that can operate on an
+** sqlite3_file for win32.
+*/
+static const sqlite3_io_methods winIoMethod = {
+ 3, /* iVersion */
+ winClose, /* xClose */
+ winRead, /* xRead */
+ winWrite, /* xWrite */
+ winTruncate, /* xTruncate */
+ winSync, /* xSync */
+ winFileSize, /* xFileSize */
+ winLock, /* xLock */
+ winUnlock, /* xUnlock */
+ winCheckReservedLock, /* xCheckReservedLock */
+ winFileControl, /* xFileControl */
+ winSectorSize, /* xSectorSize */
+ winDeviceCharacteristics, /* xDeviceCharacteristics */
+ winShmMap, /* xShmMap */
+ winShmLock, /* xShmLock */
+ winShmBarrier, /* xShmBarrier */
+ winShmUnmap, /* xShmUnmap */
+ winFetch, /* xFetch */
+ winUnfetch /* xUnfetch */
+};
+
+/*
+** This vector defines all the methods that can operate on an
+** sqlite3_file for win32 without performing any locking.
+*/
+static const sqlite3_io_methods winIoNolockMethod = {
+ 3, /* iVersion */
+ winClose, /* xClose */
+ winRead, /* xRead */
+ winWrite, /* xWrite */
+ winTruncate, /* xTruncate */
+ winSync, /* xSync */
+ winFileSize, /* xFileSize */
+ winNolockLock, /* xLock */
+ winNolockUnlock, /* xUnlock */
+ winNolockCheckReservedLock, /* xCheckReservedLock */
+ winFileControl, /* xFileControl */
+ winSectorSize, /* xSectorSize */
+ winDeviceCharacteristics, /* xDeviceCharacteristics */
+ winShmMap, /* xShmMap */
+ winShmLock, /* xShmLock */
+ winShmBarrier, /* xShmBarrier */
+ winShmUnmap, /* xShmUnmap */
+ winFetch, /* xFetch */
+ winUnfetch /* xUnfetch */
+};
+
+static winVfsAppData winAppData = {
+ &winIoMethod, /* pMethod */
+ 0, /* pAppData */
+ 0 /* bNoLock */
+};
+
+static winVfsAppData winNolockAppData = {
+ &winIoNolockMethod, /* pMethod */
+ 0, /* pAppData */
+ 1 /* bNoLock */
+};
+
+/****************************************************************************
+**************************** sqlite3_vfs methods ****************************
+**
+** This division contains the implementation of methods on the
+** sqlite3_vfs object.
+*/
+
+#if defined(__CYGWIN__)
+/*
+** Convert a filename from whatever the underlying operating system
+** supports for filenames into UTF-8. Space to hold the result is
+** obtained from malloc and must be freed by the calling function.
+*/
+static char *winConvertToUtf8Filename(const void *zFilename){
+ char *zConverted = 0;
+ if( osIsNT() ){
+ zConverted = winUnicodeToUtf8(zFilename);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ zConverted = winMbcsToUtf8(zFilename, osAreFileApisANSI());
+ }
+#endif
+ /* caller will handle out of memory */
+ return zConverted;
+}
+#endif
+
+/*
+** Convert a UTF-8 filename into whatever form the underlying
+** operating system wants filenames in. Space to hold the result
+** is obtained from malloc and must be freed by the calling
+** function.
+*/
+static void *winConvertFromUtf8Filename(const char *zFilename){
+ void *zConverted = 0;
+ if( osIsNT() ){
+ zConverted = winUtf8ToUnicode(zFilename);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ zConverted = winUtf8ToMbcs(zFilename, osAreFileApisANSI());
+ }
+#endif
+ /* caller will handle out of memory */
+ return zConverted;
+}
+
+/*
+** This function returns non-zero if the specified UTF-8 string buffer
+** ends with a directory separator character or one was successfully
+** added to it.
+*/
+static int winMakeEndInDirSep(int nBuf, char *zBuf){
+ if( zBuf ){
+ int nLen = sqlite3Strlen30(zBuf);
+ if( nLen>0 ){
+ if( winIsDirSep(zBuf[nLen-1]) ){
+ return 1;
+ }else if( nLen+1mxPathname; nBuf = nMax + 2;
+ zBuf = sqlite3MallocZero( nBuf );
+ if( !zBuf ){
+ OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+
+ /* Figure out the effective temporary directory. First, check if one
+ ** has been explicitly set by the application; otherwise, use the one
+ ** configured by the operating system.
+ */
+ nDir = nMax - (nPre + 15);
+ assert( nDir>0 );
+ if( sqlite3_temp_directory ){
+ int nDirLen = sqlite3Strlen30(sqlite3_temp_directory);
+ if( nDirLen>0 ){
+ if( !winIsDirSep(sqlite3_temp_directory[nDirLen-1]) ){
+ nDirLen++;
+ }
+ if( nDirLen>nDir ){
+ sqlite3_free(zBuf);
+ OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
+ return winLogError(SQLITE_ERROR, 0, "winGetTempname1", 0);
+ }
+ sqlite3_snprintf(nMax, zBuf, "%s", sqlite3_temp_directory);
+ }
+ }
+#if defined(__CYGWIN__)
+ else{
+ static const char *azDirs[] = {
+ 0, /* getenv("SQLITE_TMPDIR") */
+ 0, /* getenv("TMPDIR") */
+ 0, /* getenv("TMP") */
+ 0, /* getenv("TEMP") */
+ 0, /* getenv("USERPROFILE") */
+ "/var/tmp",
+ "/usr/tmp",
+ "/tmp",
+ ".",
+ 0 /* List terminator */
+ };
+ unsigned int i;
+ const char *zDir = 0;
+
+ if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
+ if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");
+ if( !azDirs[2] ) azDirs[2] = getenv("TMP");
+ if( !azDirs[3] ) azDirs[3] = getenv("TEMP");
+ if( !azDirs[4] ) azDirs[4] = getenv("USERPROFILE");
+ for(i=0; i/etilqs_XXXXXXXXXXXXXXX\0\0"
+ **
+ ** If not, return SQLITE_ERROR. The number 17 is used here in order to
+ ** account for the space used by the 15 character random suffix and the
+ ** two trailing NUL characters. The final directory separator character
+ ** has already added if it was not already present.
+ */
+ nLen = sqlite3Strlen30(zBuf);
+ if( (nLen + nPre + 17) > nBuf ){
+ sqlite3_free(zBuf);
+ OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
+ return winLogError(SQLITE_ERROR, 0, "winGetTempname5", 0);
+ }
+
+ sqlite3_snprintf(nBuf-16-nLen, zBuf+nLen, SQLITE_TEMP_FILE_PREFIX);
+
+ j = sqlite3Strlen30(zBuf);
+ sqlite3_randomness(15, &zBuf[j]);
+ for(i=0; i<15; i++, j++){
+ zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
+ }
+ zBuf[j] = 0;
+ zBuf[j+1] = 0;
+ *pzBuf = zBuf;
+
+ OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
+ return SQLITE_OK;
+}
+
+/*
+** Return TRUE if the named file is really a directory. Return false if
+** it is something other than a directory, or if there is any kind of memory
+** allocation failure.
+*/
+static int winIsDir(const void *zConverted){
+ DWORD attr;
+ int rc = 0;
+ DWORD lastErrno;
+
+ if( osIsNT() ){
+ int cnt = 0;
+ WIN32_FILE_ATTRIBUTE_DATA sAttrData;
+ memset(&sAttrData, 0, sizeof(sAttrData));
+ while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
+ GetFileExInfoStandard,
+ &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
+ if( !rc ){
+ return 0; /* Invalid name? */
+ }
+ attr = sAttrData.dwFileAttributes;
+#if SQLITE_OS_WINCE==0
+ }else{
+ attr = osGetFileAttributesA((char*)zConverted);
+#endif
+ }
+ return (attr!=INVALID_FILE_ATTRIBUTES) && (attr&FILE_ATTRIBUTE_DIRECTORY);
+}
+
+/* forward reference */
+static int winAccess(
+ sqlite3_vfs *pVfs, /* Not used on win32 */
+ const char *zFilename, /* Name of file to check */
+ int flags, /* Type of test to make on this file */
+ int *pResOut /* OUT: Result */
+);
+
+/*
+** Open a file.
+*/
+static int winOpen(
+ sqlite3_vfs *pVfs, /* Used to get maximum path length and AppData */
+ const char *zName, /* Name of the file (UTF-8) */
+ sqlite3_file *id, /* Write the SQLite file handle here */
+ int flags, /* Open mode flags */
+ int *pOutFlags /* Status return flags */
+){
+ HANDLE h;
+ DWORD lastErrno = 0;
+ DWORD dwDesiredAccess;
+ DWORD dwShareMode;
+ DWORD dwCreationDisposition;
+ DWORD dwFlagsAndAttributes = 0;
+#if SQLITE_OS_WINCE
+ int isTemp = 0;
+#endif
+ winVfsAppData *pAppData;
+ winFile *pFile = (winFile*)id;
+ void *zConverted; /* Filename in OS encoding */
+ const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
+ int cnt = 0;
+
+ /* If argument zPath is a NULL pointer, this function is required to open
+ ** a temporary file. Use this buffer to store the file name in.
+ */
+ char *zTmpname = 0; /* For temporary filename, if necessary. */
+
+ int rc = SQLITE_OK; /* Function Return Code */
+#if !defined(NDEBUG) || SQLITE_OS_WINCE
+ int eType = flags&0xFFFFFF00; /* Type of file to open */
+#endif
+
+ int isExclusive = (flags & SQLITE_OPEN_EXCLUSIVE);
+ int isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE);
+ int isCreate = (flags & SQLITE_OPEN_CREATE);
+ int isReadonly = (flags & SQLITE_OPEN_READONLY);
+ int isReadWrite = (flags & SQLITE_OPEN_READWRITE);
+
+#ifndef NDEBUG
+ int isOpenJournal = (isCreate && (
+ eType==SQLITE_OPEN_MASTER_JOURNAL
+ || eType==SQLITE_OPEN_MAIN_JOURNAL
+ || eType==SQLITE_OPEN_WAL
+ ));
+#endif
+
+ OSTRACE(("OPEN name=%s, pFile=%p, flags=%x, pOutFlags=%p\n",
+ zUtf8Name, id, flags, pOutFlags));
+
+ /* Check the following statements are true:
+ **
+ ** (a) Exactly one of the READWRITE and READONLY flags must be set, and
+ ** (b) if CREATE is set, then READWRITE must also be set, and
+ ** (c) if EXCLUSIVE is set, then CREATE must also be set.
+ ** (d) if DELETEONCLOSE is set, then CREATE must also be set.
+ */
+ assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
+ assert(isCreate==0 || isReadWrite);
+ assert(isExclusive==0 || isCreate);
+ assert(isDelete==0 || isCreate);
+
+ /* The main DB, main journal, WAL file and master journal are never
+ ** automatically deleted. Nor are they ever temporary files. */
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
+
+ /* Assert that the upper layer has set one of the "file-type" flags. */
+ assert( eType==SQLITE_OPEN_MAIN_DB || eType==SQLITE_OPEN_TEMP_DB
+ || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL
+ || eType==SQLITE_OPEN_SUBJOURNAL || eType==SQLITE_OPEN_MASTER_JOURNAL
+ || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
+ );
+
+ assert( pFile!=0 );
+ memset(pFile, 0, sizeof(winFile));
+ pFile->h = INVALID_HANDLE_VALUE;
+
+#if SQLITE_OS_WINRT
+ if( !zUtf8Name && !sqlite3_temp_directory ){
+ sqlite3_log(SQLITE_ERROR,
+ "sqlite3_temp_directory variable should be set for WinRT");
+ }
+#endif
+
+ /* If the second argument to this function is NULL, generate a
+ ** temporary file name to use
+ */
+ if( !zUtf8Name ){
+ assert( isDelete && !isOpenJournal );
+ rc = winGetTempname(pVfs, &zTmpname);
+ if( rc!=SQLITE_OK ){
+ OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
+ return rc;
+ }
+ zUtf8Name = zTmpname;
+ }
+
+ /* Database filenames are double-zero terminated if they are not
+ ** URIs with parameters. Hence, they can always be passed into
+ ** sqlite3_uri_parameter().
+ */
+ assert( (eType!=SQLITE_OPEN_MAIN_DB) || (flags & SQLITE_OPEN_URI) ||
+ zUtf8Name[sqlite3Strlen30(zUtf8Name)+1]==0 );
+
+ /* Convert the filename to the system encoding. */
+ zConverted = winConvertFromUtf8Filename(zUtf8Name);
+ if( zConverted==0 ){
+ sqlite3_free(zTmpname);
+ OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+
+ if( winIsDir(zConverted) ){
+ sqlite3_free(zConverted);
+ sqlite3_free(zTmpname);
+ OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
+ return SQLITE_CANTOPEN_ISDIR;
+ }
+
+ if( isReadWrite ){
+ dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
+ }else{
+ dwDesiredAccess = GENERIC_READ;
+ }
+
+ /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is
+ ** created. SQLite doesn't use it to indicate "exclusive access"
+ ** as it is usually understood.
+ */
+ if( isExclusive ){
+ /* Creates a new file, only if it does not already exist. */
+ /* If the file exists, it fails. */
+ dwCreationDisposition = CREATE_NEW;
+ }else if( isCreate ){
+ /* Open existing file, or create if it doesn't exist */
+ dwCreationDisposition = OPEN_ALWAYS;
+ }else{
+ /* Opens a file, only if it exists. */
+ dwCreationDisposition = OPEN_EXISTING;
+ }
+
+ dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
+
+ if( isDelete ){
+#if SQLITE_OS_WINCE
+ dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
+ isTemp = 1;
+#else
+ dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
+ | FILE_ATTRIBUTE_HIDDEN
+ | FILE_FLAG_DELETE_ON_CLOSE;
+#endif
+ }else{
+ dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
+ }
+ /* Reports from the internet are that performance is always
+ ** better if FILE_FLAG_RANDOM_ACCESS is used. Ticket #2699. */
+#if SQLITE_OS_WINCE
+ dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
+#endif
+
+ if( osIsNT() ){
+#if SQLITE_OS_WINRT
+ CREATEFILE2_EXTENDED_PARAMETERS extendedParameters;
+ extendedParameters.dwSize = sizeof(CREATEFILE2_EXTENDED_PARAMETERS);
+ extendedParameters.dwFileAttributes =
+ dwFlagsAndAttributes & FILE_ATTRIBUTE_MASK;
+ extendedParameters.dwFileFlags = dwFlagsAndAttributes & FILE_FLAG_MASK;
+ extendedParameters.dwSecurityQosFlags = SECURITY_ANONYMOUS;
+ extendedParameters.lpSecurityAttributes = NULL;
+ extendedParameters.hTemplateFile = NULL;
+ do{
+ h = osCreateFile2((LPCWSTR)zConverted,
+ dwDesiredAccess,
+ dwShareMode,
+ dwCreationDisposition,
+ &extendedParameters);
+ if( h!=INVALID_HANDLE_VALUE ) break;
+ if( isReadWrite ){
+ int rc2, isRO = 0;
+ sqlite3BeginBenignMalloc();
+ rc2 = winAccess(pVfs, zName, SQLITE_ACCESS_READ, &isRO);
+ sqlite3EndBenignMalloc();
+ if( rc2==SQLITE_OK && isRO ) break;
+ }
+ }while( winRetryIoerr(&cnt, &lastErrno) );
+#else
+ do{
+ h = osCreateFileW((LPCWSTR)zConverted,
+ dwDesiredAccess,
+ dwShareMode, NULL,
+ dwCreationDisposition,
+ dwFlagsAndAttributes,
+ NULL);
+ if( h!=INVALID_HANDLE_VALUE ) break;
+ if( isReadWrite ){
+ int rc2, isRO = 0;
+ sqlite3BeginBenignMalloc();
+ rc2 = winAccess(pVfs, zName, SQLITE_ACCESS_READ, &isRO);
+ sqlite3EndBenignMalloc();
+ if( rc2==SQLITE_OK && isRO ) break;
+ }
+ }while( winRetryIoerr(&cnt, &lastErrno) );
+#endif
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ do{
+ h = osCreateFileA((LPCSTR)zConverted,
+ dwDesiredAccess,
+ dwShareMode, NULL,
+ dwCreationDisposition,
+ dwFlagsAndAttributes,
+ NULL);
+ if( h!=INVALID_HANDLE_VALUE ) break;
+ if( isReadWrite ){
+ int rc2, isRO = 0;
+ sqlite3BeginBenignMalloc();
+ rc2 = winAccess(pVfs, zName, SQLITE_ACCESS_READ, &isRO);
+ sqlite3EndBenignMalloc();
+ if( rc2==SQLITE_OK && isRO ) break;
+ }
+ }while( winRetryIoerr(&cnt, &lastErrno) );
+ }
+#endif
+ winLogIoerr(cnt, __LINE__);
+
+ OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
+ dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
+
+ if( h==INVALID_HANDLE_VALUE ){
+ sqlite3_free(zConverted);
+ sqlite3_free(zTmpname);
+ if( isReadWrite && !isExclusive ){
+ return winOpen(pVfs, zName, id,
+ ((flags|SQLITE_OPEN_READONLY) &
+ ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
+ pOutFlags);
+ }else{
+ pFile->lastErrno = lastErrno;
+ winLogError(SQLITE_CANTOPEN, pFile->lastErrno, "winOpen", zUtf8Name);
+ return SQLITE_CANTOPEN_BKPT;
+ }
+ }
+
+ if( pOutFlags ){
+ if( isReadWrite ){
+ *pOutFlags = SQLITE_OPEN_READWRITE;
+ }else{
+ *pOutFlags = SQLITE_OPEN_READONLY;
+ }
+ }
+
+ OSTRACE(("OPEN file=%p, name=%s, access=%lx, pOutFlags=%p, *pOutFlags=%d, "
+ "rc=%s\n", h, zUtf8Name, dwDesiredAccess, pOutFlags, pOutFlags ?
+ *pOutFlags : 0, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
+
+ pAppData = (winVfsAppData*)pVfs->pAppData;
+
+#if SQLITE_OS_WINCE
+ {
+ if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
+ && ((pAppData==NULL) || !pAppData->bNoLock)
+ && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
+ ){
+ osCloseHandle(h);
+ sqlite3_free(zConverted);
+ sqlite3_free(zTmpname);
+ OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
+ return rc;
+ }
+ }
+ if( isTemp ){
+ pFile->zDeleteOnClose = zConverted;
+ }else
+#endif
+ {
+ sqlite3_free(zConverted);
+ }
+
+ sqlite3_free(zTmpname);
+ pFile->pMethod = pAppData ? pAppData->pMethod : &winIoMethod;
+ pFile->pVfs = pVfs;
+ pFile->h = h;
+ if( isReadonly ){
+ pFile->ctrlFlags |= WINFILE_RDONLY;
+ }
+ if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
+ pFile->ctrlFlags |= WINFILE_PSOW;
+ }
+ pFile->lastErrno = NO_ERROR;
+ pFile->zPath = zName;
+#if SQLITE_MAX_MMAP_SIZE>0
+ pFile->hMap = NULL;
+ pFile->pMapRegion = 0;
+ pFile->mmapSize = 0;
+ pFile->mmapSizeActual = 0;
+ pFile->mmapSizeMax = sqlite3GlobalConfig.szMmap;
+#endif
+
+ OpenCounter(+1);
+ return rc;
+}
+
+/*
+** Delete the named file.
+**
+** Note that Windows does not allow a file to be deleted if some other
+** process has it open. Sometimes a virus scanner or indexing program
+** will open a journal file shortly after it is created in order to do
+** whatever it does. While this other process is holding the
+** file open, we will be unable to delete it. To work around this
+** problem, we delay 100 milliseconds and try to delete again. Up
+** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
+** up and returning an error.
+*/
+static int winDelete(
+ sqlite3_vfs *pVfs, /* Not used on win32 */
+ const char *zFilename, /* Name of file to delete */
+ int syncDir /* Not used on win32 */
+){
+ int cnt = 0;
+ int rc;
+ DWORD attr;
+ DWORD lastErrno = 0;
+ void *zConverted;
+ UNUSED_PARAMETER(pVfs);
+ UNUSED_PARAMETER(syncDir);
+
+ SimulateIOError(return SQLITE_IOERR_DELETE);
+ OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));
+
+ zConverted = winConvertFromUtf8Filename(zFilename);
+ if( zConverted==0 ){
+ OSTRACE(("DELETE name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ if( osIsNT() ){
+ do {
+#if SQLITE_OS_WINRT
+ WIN32_FILE_ATTRIBUTE_DATA sAttrData;
+ memset(&sAttrData, 0, sizeof(sAttrData));
+ if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
+ &sAttrData) ){
+ attr = sAttrData.dwFileAttributes;
+ }else{
+ lastErrno = osGetLastError();
+ if( lastErrno==ERROR_FILE_NOT_FOUND
+ || lastErrno==ERROR_PATH_NOT_FOUND ){
+ rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ break;
+ }
+#else
+ attr = osGetFileAttributesW(zConverted);
+#endif
+ if ( attr==INVALID_FILE_ATTRIBUTES ){
+ lastErrno = osGetLastError();
+ if( lastErrno==ERROR_FILE_NOT_FOUND
+ || lastErrno==ERROR_PATH_NOT_FOUND ){
+ rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ break;
+ }
+ if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
+ rc = SQLITE_ERROR; /* Files only. */
+ break;
+ }
+ if ( osDeleteFileW(zConverted) ){
+ rc = SQLITE_OK; /* Deleted OK. */
+ break;
+ }
+ if ( !winRetryIoerr(&cnt, &lastErrno) ){
+ rc = SQLITE_ERROR; /* No more retries. */
+ break;
+ }
+ } while(1);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ do {
+ attr = osGetFileAttributesA(zConverted);
+ if ( attr==INVALID_FILE_ATTRIBUTES ){
+ lastErrno = osGetLastError();
+ if( lastErrno==ERROR_FILE_NOT_FOUND
+ || lastErrno==ERROR_PATH_NOT_FOUND ){
+ rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ break;
+ }
+ if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
+ rc = SQLITE_ERROR; /* Files only. */
+ break;
+ }
+ if ( osDeleteFileA(zConverted) ){
+ rc = SQLITE_OK; /* Deleted OK. */
+ break;
+ }
+ if ( !winRetryIoerr(&cnt, &lastErrno) ){
+ rc = SQLITE_ERROR; /* No more retries. */
+ break;
+ }
+ } while(1);
+ }
+#endif
+ if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
+ rc = winLogError(SQLITE_IOERR_DELETE, lastErrno, "winDelete", zFilename);
+ }else{
+ winLogIoerr(cnt, __LINE__);
+ }
+ sqlite3_free(zConverted);
+ OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** Check the existence and status of a file.
+*/
+static int winAccess(
+ sqlite3_vfs *pVfs, /* Not used on win32 */
+ const char *zFilename, /* Name of file to check */
+ int flags, /* Type of test to make on this file */
+ int *pResOut /* OUT: Result */
+){
+ DWORD attr;
+ int rc = 0;
+ DWORD lastErrno = 0;
+ void *zConverted;
+ UNUSED_PARAMETER(pVfs);
+
+ SimulateIOError( return SQLITE_IOERR_ACCESS; );
+ OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
+ zFilename, flags, pResOut));
+
+ zConverted = winConvertFromUtf8Filename(zFilename);
+ if( zConverted==0 ){
+ OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ if( osIsNT() ){
+ int cnt = 0;
+ WIN32_FILE_ATTRIBUTE_DATA sAttrData;
+ memset(&sAttrData, 0, sizeof(sAttrData));
+ while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
+ GetFileExInfoStandard,
+ &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
+ if( rc ){
+ /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
+ ** as if it does not exist.
+ */
+ if( flags==SQLITE_ACCESS_EXISTS
+ && sAttrData.nFileSizeHigh==0
+ && sAttrData.nFileSizeLow==0 ){
+ attr = INVALID_FILE_ATTRIBUTES;
+ }else{
+ attr = sAttrData.dwFileAttributes;
+ }
+ }else{
+ winLogIoerr(cnt, __LINE__);
+ if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){
+ sqlite3_free(zConverted);
+ return winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess",
+ zFilename);
+ }else{
+ attr = INVALID_FILE_ATTRIBUTES;
+ }
+ }
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ attr = osGetFileAttributesA((char*)zConverted);
+ }
+#endif
+ sqlite3_free(zConverted);
+ switch( flags ){
+ case SQLITE_ACCESS_READ:
+ case SQLITE_ACCESS_EXISTS:
+ rc = attr!=INVALID_FILE_ATTRIBUTES;
+ break;
+ case SQLITE_ACCESS_READWRITE:
+ rc = attr!=INVALID_FILE_ATTRIBUTES &&
+ (attr & FILE_ATTRIBUTE_READONLY)==0;
+ break;
+ default:
+ assert(!"Invalid flags argument");
+ }
+ *pResOut = rc;
+ OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
+ zFilename, pResOut, *pResOut));
+ return SQLITE_OK;
+}
+
+/*
+** Returns non-zero if the specified path name starts with a drive letter
+** followed by a colon character.
+*/
+static BOOL winIsDriveLetterAndColon(
+ const char *zPathname
+){
+ return ( sqlite3Isalpha(zPathname[0]) && zPathname[1]==':' );
+}
+
+/*
+** Returns non-zero if the specified path name should be used verbatim. If
+** non-zero is returned from this function, the calling function must simply
+** use the provided path name verbatim -OR- resolve it into a full path name
+** using the GetFullPathName Win32 API function (if available).
+*/
+static BOOL winIsVerbatimPathname(
+ const char *zPathname
+){
+ /*
+ ** If the path name starts with a forward slash or a backslash, it is either
+ ** a legal UNC name, a volume relative path, or an absolute path name in the
+ ** "Unix" format on Windows. There is no easy way to differentiate between
+ ** the final two cases; therefore, we return the safer return value of TRUE
+ ** so that callers of this function will simply use it verbatim.
+ */
+ if ( winIsDirSep(zPathname[0]) ){
+ return TRUE;
+ }
+
+ /*
+ ** If the path name starts with a letter and a colon it is either a volume
+ ** relative path or an absolute path. Callers of this function must not
+ ** attempt to treat it as a relative path name (i.e. they should simply use
+ ** it verbatim).
+ */
+ if ( winIsDriveLetterAndColon(zPathname) ){
+ return TRUE;
+ }
+
+ /*
+ ** If we get to this point, the path name should almost certainly be a purely
+ ** relative one (i.e. not a UNC name, not absolute, and not volume relative).
+ */
+ return FALSE;
+}
+
+/*
+** Turn a relative pathname into a full pathname. Write the full
+** pathname into zOut[]. zOut[] will be at least pVfs->mxPathname
+** bytes in size.
+*/
+static int winFullPathname(
+ sqlite3_vfs *pVfs, /* Pointer to vfs object */
+ const char *zRelative, /* Possibly relative input path */
+ int nFull, /* Size of output buffer in bytes */
+ char *zFull /* Output buffer */
+){
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
+ DWORD nByte;
+ void *zConverted;
+ char *zOut;
+#endif
+
+ /* If this path name begins with "/X:", where "X" is any alphabetic
+ ** character, discard the initial "/" from the pathname.
+ */
+ if( zRelative[0]=='/' && winIsDriveLetterAndColon(zRelative+1) ){
+ zRelative++;
+ }
+
+#if defined(__CYGWIN__)
+ SimulateIOError( return SQLITE_ERROR );
+ UNUSED_PARAMETER(nFull);
+ assert( nFull>=pVfs->mxPathname );
+ if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
+ /*
+ ** NOTE: We are dealing with a relative path name and the data
+ ** directory has been set. Therefore, use it as the basis
+ ** for converting the relative path name to an absolute
+ ** one by prepending the data directory and a slash.
+ */
+ char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
+ if( !zOut ){
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ if( cygwin_conv_path(
+ (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A) |
+ CCP_RELATIVE, zRelative, zOut, pVfs->mxPathname+1)<0 ){
+ sqlite3_free(zOut);
+ return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
+ "winFullPathname1", zRelative);
+ }else{
+ char *zUtf8 = winConvertToUtf8Filename(zOut);
+ if( !zUtf8 ){
+ sqlite3_free(zOut);
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
+ sqlite3_data_directory, winGetDirSep(), zUtf8);
+ sqlite3_free(zUtf8);
+ sqlite3_free(zOut);
+ }
+ }else{
+ char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
+ if( !zOut ){
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ if( cygwin_conv_path(
+ (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A),
+ zRelative, zOut, pVfs->mxPathname+1)<0 ){
+ sqlite3_free(zOut);
+ return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
+ "winFullPathname2", zRelative);
+ }else{
+ char *zUtf8 = winConvertToUtf8Filename(zOut);
+ if( !zUtf8 ){
+ sqlite3_free(zOut);
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zUtf8);
+ sqlite3_free(zUtf8);
+ sqlite3_free(zOut);
+ }
+ }
+ return SQLITE_OK;
+#endif
+
+#if (SQLITE_OS_WINCE || SQLITE_OS_WINRT) && !defined(__CYGWIN__)
+ SimulateIOError( return SQLITE_ERROR );
+ /* WinCE has no concept of a relative pathname, or so I am told. */
+ /* WinRT has no way to convert a relative path to an absolute one. */
+ if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
+ /*
+ ** NOTE: We are dealing with a relative path name and the data
+ ** directory has been set. Therefore, use it as the basis
+ ** for converting the relative path name to an absolute
+ ** one by prepending the data directory and a backslash.
+ */
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
+ sqlite3_data_directory, winGetDirSep(), zRelative);
+ }else{
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zRelative);
+ }
+ return SQLITE_OK;
+#endif
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
+ /* It's odd to simulate an io-error here, but really this is just
+ ** using the io-error infrastructure to test that SQLite handles this
+ ** function failing. This function could fail if, for example, the
+ ** current working directory has been unlinked.
+ */
+ SimulateIOError( return SQLITE_ERROR );
+ if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
+ /*
+ ** NOTE: We are dealing with a relative path name and the data
+ ** directory has been set. Therefore, use it as the basis
+ ** for converting the relative path name to an absolute
+ ** one by prepending the data directory and a backslash.
+ */
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
+ sqlite3_data_directory, winGetDirSep(), zRelative);
+ return SQLITE_OK;
+ }
+ zConverted = winConvertFromUtf8Filename(zRelative);
+ if( zConverted==0 ){
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ if( osIsNT() ){
+ LPWSTR zTemp;
+ nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
+ if( nByte==0 ){
+ sqlite3_free(zConverted);
+ return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
+ "winFullPathname1", zRelative);
+ }
+ nByte += 3;
+ zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
+ if( zTemp==0 ){
+ sqlite3_free(zConverted);
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
+ if( nByte==0 ){
+ sqlite3_free(zConverted);
+ sqlite3_free(zTemp);
+ return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
+ "winFullPathname2", zRelative);
+ }
+ sqlite3_free(zConverted);
+ zOut = winUnicodeToUtf8(zTemp);
+ sqlite3_free(zTemp);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ char *zTemp;
+ nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
+ if( nByte==0 ){
+ sqlite3_free(zConverted);
+ return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
+ "winFullPathname3", zRelative);
+ }
+ nByte += 3;
+ zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
+ if( zTemp==0 ){
+ sqlite3_free(zConverted);
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+ nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
+ if( nByte==0 ){
+ sqlite3_free(zConverted);
+ sqlite3_free(zTemp);
+ return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
+ "winFullPathname4", zRelative);
+ }
+ sqlite3_free(zConverted);
+ zOut = winMbcsToUtf8(zTemp, osAreFileApisANSI());
+ sqlite3_free(zTemp);
+ }
+#endif
+ if( zOut ){
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zOut);
+ sqlite3_free(zOut);
+ return SQLITE_OK;
+ }else{
+ return SQLITE_IOERR_NOMEM_BKPT;
+ }
+#endif
+}
+
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+/*
+** Interfaces for opening a shared library, finding entry points
+** within the shared library, and closing the shared library.
+*/
+static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
+ HANDLE h;
+#if defined(__CYGWIN__)
+ int nFull = pVfs->mxPathname+1;
+ char *zFull = sqlite3MallocZero( nFull );
+ void *zConverted = 0;
+ if( zFull==0 ){
+ OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
+ return 0;
+ }
+ if( winFullPathname(pVfs, zFilename, nFull, zFull)!=SQLITE_OK ){
+ sqlite3_free(zFull);
+ OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
+ return 0;
+ }
+ zConverted = winConvertFromUtf8Filename(zFull);
+ sqlite3_free(zFull);
+#else
+ void *zConverted = winConvertFromUtf8Filename(zFilename);
+ UNUSED_PARAMETER(pVfs);
+#endif
+ if( zConverted==0 ){
+ OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
+ return 0;
+ }
+ if( osIsNT() ){
+#if SQLITE_OS_WINRT
+ h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
+#else
+ h = osLoadLibraryW((LPCWSTR)zConverted);
+#endif
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ h = osLoadLibraryA((char*)zConverted);
+ }
+#endif
+ OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)h));
+ sqlite3_free(zConverted);
+ return (void*)h;
+}
+static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
+ UNUSED_PARAMETER(pVfs);
+ winGetLastErrorMsg(osGetLastError(), nBuf, zBufOut);
+}
+static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
+ FARPROC proc;
+ UNUSED_PARAMETER(pVfs);
+ proc = osGetProcAddressA((HANDLE)pH, zSym);
+ OSTRACE(("DLSYM handle=%p, symbol=%s, address=%p\n",
+ (void*)pH, zSym, (void*)proc));
+ return (void(*)(void))proc;
+}
+static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
+ UNUSED_PARAMETER(pVfs);
+ osFreeLibrary((HANDLE)pHandle);
+ OSTRACE(("DLCLOSE handle=%p\n", (void*)pHandle));
+}
+#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
+ #define winDlOpen 0
+ #define winDlError 0
+ #define winDlSym 0
+ #define winDlClose 0
+#endif
+
+/* State information for the randomness gatherer. */
+typedef struct EntropyGatherer EntropyGatherer;
+struct EntropyGatherer {
+ unsigned char *a; /* Gather entropy into this buffer */
+ int na; /* Size of a[] in bytes */
+ int i; /* XOR next input into a[i] */
+ int nXor; /* Number of XOR operations done */
+};
+
+#if !defined(SQLITE_TEST) && !defined(SQLITE_OMIT_RANDOMNESS)
+/* Mix sz bytes of entropy into p. */
+static void xorMemory(EntropyGatherer *p, unsigned char *x, int sz){
+ int j, k;
+ for(j=0, k=p->i; ja[k++] ^= x[j];
+ if( k>=p->na ) k = 0;
+ }
+ p->i = k;
+ p->nXor += sz;
+}
+#endif /* !defined(SQLITE_TEST) && !defined(SQLITE_OMIT_RANDOMNESS) */
+
+/*
+** Write up to nBuf bytes of randomness into zBuf.
+*/
+static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+#if defined(SQLITE_TEST) || defined(SQLITE_OMIT_RANDOMNESS)
+ UNUSED_PARAMETER(pVfs);
+ memset(zBuf, 0, nBuf);
+ return nBuf;
+#else
+ EntropyGatherer e;
+ UNUSED_PARAMETER(pVfs);
+ memset(zBuf, 0, nBuf);
+ e.a = (unsigned char*)zBuf;
+ e.na = nBuf;
+ e.nXor = 0;
+ e.i = 0;
+ {
+ SYSTEMTIME x;
+ osGetSystemTime(&x);
+ xorMemory(&e, (unsigned char*)&x, sizeof(SYSTEMTIME));
+ }
+ {
+ DWORD pid = osGetCurrentProcessId();
+ xorMemory(&e, (unsigned char*)&pid, sizeof(DWORD));
+ }
+#if SQLITE_OS_WINRT
+ {
+ ULONGLONG cnt = osGetTickCount64();
+ xorMemory(&e, (unsigned char*)&cnt, sizeof(ULONGLONG));
+ }
+#else
+ {
+ DWORD cnt = osGetTickCount();
+ xorMemory(&e, (unsigned char*)&cnt, sizeof(DWORD));
+ }
+#endif /* SQLITE_OS_WINRT */
+ {
+ LARGE_INTEGER i;
+ osQueryPerformanceCounter(&i);
+ xorMemory(&e, (unsigned char*)&i, sizeof(LARGE_INTEGER));
+ }
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
+ {
+ UUID id;
+ memset(&id, 0, sizeof(UUID));
+ osUuidCreate(&id);
+ xorMemory(&e, (unsigned char*)&id, sizeof(UUID));
+ memset(&id, 0, sizeof(UUID));
+ osUuidCreateSequential(&id);
+ xorMemory(&e, (unsigned char*)&id, sizeof(UUID));
+ }
+#endif /* !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID */
+ return e.nXor>nBuf ? nBuf : e.nXor;
+#endif /* defined(SQLITE_TEST) || defined(SQLITE_OMIT_RANDOMNESS) */
+}
+
+
+/*
+** Sleep for a little while. Return the amount of time slept.
+*/
+static int winSleep(sqlite3_vfs *pVfs, int microsec){
+ sqlite3_win32_sleep((microsec+999)/1000);
+ UNUSED_PARAMETER(pVfs);
+ return ((microsec+999)/1000)*1000;
+}
+
+/*
+** The following variable, if set to a non-zero value, is interpreted as
+** the number of seconds since 1970 and is used to set the result of
+** sqlite3OsCurrentTime() during testing.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_current_time = 0; /* Fake system time in seconds since 1970. */
+#endif
+
+/*
+** Find the current time (in Universal Coordinated Time). Write into *piNow
+** the current time and date as a Julian Day number times 86_400_000. In
+** other words, write into *piNow the number of milliseconds since the Julian
+** epoch of noon in Greenwich on November 24, 4714 B.C according to the
+** proleptic Gregorian calendar.
+**
+** On success, return SQLITE_OK. Return SQLITE_ERROR if the time and date
+** cannot be found.
+*/
+static int winCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
+ /* FILETIME structure is a 64-bit value representing the number of
+ 100-nanosecond intervals since January 1, 1601 (= JD 2305813.5).
+ */
+ FILETIME ft;
+ static const sqlite3_int64 winFiletimeEpoch = 23058135*(sqlite3_int64)8640000;
+#ifdef SQLITE_TEST
+ static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
+#endif
+ /* 2^32 - to avoid use of LL and warnings in gcc */
+ static const sqlite3_int64 max32BitValue =
+ (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 +
+ (sqlite3_int64)294967296;
+
+#if SQLITE_OS_WINCE
+ SYSTEMTIME time;
+ osGetSystemTime(&time);
+ /* if SystemTimeToFileTime() fails, it returns zero. */
+ if (!osSystemTimeToFileTime(&time,&ft)){
+ return SQLITE_ERROR;
+ }
+#else
+ osGetSystemTimeAsFileTime( &ft );
+#endif
+
+ *piNow = winFiletimeEpoch +
+ ((((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) +
+ (sqlite3_int64)ft.dwLowDateTime)/(sqlite3_int64)10000;
+
+#ifdef SQLITE_TEST
+ if( sqlite3_current_time ){
+ *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
+ }
+#endif
+ UNUSED_PARAMETER(pVfs);
+ return SQLITE_OK;
+}
+
+/*
+** Find the current time (in Universal Coordinated Time). Write the
+** current time and date as a Julian Day number into *prNow and
+** return 0. Return 1 if the time and date cannot be found.
+*/
+static int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
+ int rc;
+ sqlite3_int64 i;
+ rc = winCurrentTimeInt64(pVfs, &i);
+ if( !rc ){
+ *prNow = i/86400000.0;
+ }
+ return rc;
+}
+
+/*
+** The idea is that this function works like a combination of
+** GetLastError() and FormatMessage() on Windows (or errno and
+** strerror_r() on Unix). After an error is returned by an OS
+** function, SQLite calls this function with zBuf pointing to
+** a buffer of nBuf bytes. The OS layer should populate the
+** buffer with a nul-terminated UTF-8 encoded error message
+** describing the last IO error to have occurred within the calling
+** thread.
+**
+** If the error message is too large for the supplied buffer,
+** it should be truncated. The return value of xGetLastError
+** is zero if the error message fits in the buffer, or non-zero
+** otherwise (if the message was truncated). If non-zero is returned,
+** then it is not necessary to include the nul-terminator character
+** in the output buffer.
+**
+** Not supplying an error message will have no adverse effect
+** on SQLite. It is fine to have an implementation that never
+** returns an error message:
+**
+** int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+** assert(zBuf[0]=='\0');
+** return 0;
+** }
+**
+** However if an error message is supplied, it will be incorporated
+** by sqlite into the error message available to the user using
+** sqlite3_errmsg(), possibly making IO errors easier to debug.
+*/
+static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+ DWORD e = osGetLastError();
+ UNUSED_PARAMETER(pVfs);
+ if( nBuf>0 ) winGetLastErrorMsg(e, nBuf, zBuf);
+ return e;
+}
+
+/*
+** Initialize and deinitialize the operating system interface.
+*/
+SQLITE_API int sqlite3_os_init(void){
+ static sqlite3_vfs winVfs = {
+ 3, /* iVersion */
+ sizeof(winFile), /* szOsFile */
+ SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
+ 0, /* pNext */
+ "win32", /* zName */
+ &winAppData, /* pAppData */
+ winOpen, /* xOpen */
+ winDelete, /* xDelete */
+ winAccess, /* xAccess */
+ winFullPathname, /* xFullPathname */
+ winDlOpen, /* xDlOpen */
+ winDlError, /* xDlError */
+ winDlSym, /* xDlSym */
+ winDlClose, /* xDlClose */
+ winRandomness, /* xRandomness */
+ winSleep, /* xSleep */
+ winCurrentTime, /* xCurrentTime */
+ winGetLastError, /* xGetLastError */
+ winCurrentTimeInt64, /* xCurrentTimeInt64 */
+ winSetSystemCall, /* xSetSystemCall */
+ winGetSystemCall, /* xGetSystemCall */
+ winNextSystemCall, /* xNextSystemCall */
+ };
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ static sqlite3_vfs winLongPathVfs = {
+ 3, /* iVersion */
+ sizeof(winFile), /* szOsFile */
+ SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
+ 0, /* pNext */
+ "win32-longpath", /* zName */
+ &winAppData, /* pAppData */
+ winOpen, /* xOpen */
+ winDelete, /* xDelete */
+ winAccess, /* xAccess */
+ winFullPathname, /* xFullPathname */
+ winDlOpen, /* xDlOpen */
+ winDlError, /* xDlError */
+ winDlSym, /* xDlSym */
+ winDlClose, /* xDlClose */
+ winRandomness, /* xRandomness */
+ winSleep, /* xSleep */
+ winCurrentTime, /* xCurrentTime */
+ winGetLastError, /* xGetLastError */
+ winCurrentTimeInt64, /* xCurrentTimeInt64 */
+ winSetSystemCall, /* xSetSystemCall */
+ winGetSystemCall, /* xGetSystemCall */
+ winNextSystemCall, /* xNextSystemCall */
+ };
+#endif
+ static sqlite3_vfs winNolockVfs = {
+ 3, /* iVersion */
+ sizeof(winFile), /* szOsFile */
+ SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
+ 0, /* pNext */
+ "win32-none", /* zName */
+ &winNolockAppData, /* pAppData */
+ winOpen, /* xOpen */
+ winDelete, /* xDelete */
+ winAccess, /* xAccess */
+ winFullPathname, /* xFullPathname */
+ winDlOpen, /* xDlOpen */
+ winDlError, /* xDlError */
+ winDlSym, /* xDlSym */
+ winDlClose, /* xDlClose */
+ winRandomness, /* xRandomness */
+ winSleep, /* xSleep */
+ winCurrentTime, /* xCurrentTime */
+ winGetLastError, /* xGetLastError */
+ winCurrentTimeInt64, /* xCurrentTimeInt64 */
+ winSetSystemCall, /* xSetSystemCall */
+ winGetSystemCall, /* xGetSystemCall */
+ winNextSystemCall, /* xNextSystemCall */
+ };
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ static sqlite3_vfs winLongPathNolockVfs = {
+ 3, /* iVersion */
+ sizeof(winFile), /* szOsFile */
+ SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
+ 0, /* pNext */
+ "win32-longpath-none", /* zName */
+ &winNolockAppData, /* pAppData */
+ winOpen, /* xOpen */
+ winDelete, /* xDelete */
+ winAccess, /* xAccess */
+ winFullPathname, /* xFullPathname */
+ winDlOpen, /* xDlOpen */
+ winDlError, /* xDlError */
+ winDlSym, /* xDlSym */
+ winDlClose, /* xDlClose */
+ winRandomness, /* xRandomness */
+ winSleep, /* xSleep */
+ winCurrentTime, /* xCurrentTime */
+ winGetLastError, /* xGetLastError */
+ winCurrentTimeInt64, /* xCurrentTimeInt64 */
+ winSetSystemCall, /* xSetSystemCall */
+ winGetSystemCall, /* xGetSystemCall */
+ winNextSystemCall, /* xNextSystemCall */
+ };
+#endif
+
+ /* Double-check that the aSyscall[] array has been constructed
+ ** correctly. See ticket [bb3a86e890c8e96ab] */
+ assert( ArraySize(aSyscall)==80 );
+
+ /* get memory map allocation granularity */
+ memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
+#if SQLITE_OS_WINRT
+ osGetNativeSystemInfo(&winSysInfo);
+#else
+ osGetSystemInfo(&winSysInfo);
+#endif
+ assert( winSysInfo.dwAllocationGranularity>0 );
+ assert( winSysInfo.dwPageSize>0 );
+
+ sqlite3_vfs_register(&winVfs, 1);
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ sqlite3_vfs_register(&winLongPathVfs, 0);
+#endif
+
+ sqlite3_vfs_register(&winNolockVfs, 0);
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ sqlite3_vfs_register(&winLongPathNolockVfs, 0);
+#endif
+
+#ifndef SQLITE_OMIT_WAL
+ winBigLock = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1);
+#endif
+
+ return SQLITE_OK;
+}
+
+SQLITE_API int sqlite3_os_end(void){
+#if SQLITE_OS_WINRT
+ if( sleepObj!=NULL ){
+ osCloseHandle(sleepObj);
+ sleepObj = NULL;
+ }
+#endif
+
+#ifndef SQLITE_OMIT_WAL
+ winBigLock = 0;
+#endif
+
+ return SQLITE_OK;
+}
+
+#endif /* SQLITE_OS_WIN */
+
+/************** End of os_win.c **********************************************/
+/************** Begin file memdb.c *******************************************/
+/*
+** 2016-09-07
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file implements an in-memory VFS. A database is held as a contiguous
+** block of memory.
+**
+** This file also implements interface sqlite3_serialize() and
+** sqlite3_deserialize().
+*/
+/* #include "sqliteInt.h" */
+#ifdef SQLITE_ENABLE_DESERIALIZE
+
+/*
+** Forward declaration of objects used by this utility
+*/
+typedef struct sqlite3_vfs MemVfs;
+typedef struct MemFile MemFile;
+
+/* Access to a lower-level VFS that (might) implement dynamic loading,
+** access to randomness, etc.
+*/
+#define ORIGVFS(p) ((sqlite3_vfs*)((p)->pAppData))
+
+/* An open file */
+struct MemFile {
+ sqlite3_file base; /* IO methods */
+ sqlite3_int64 sz; /* Size of the file */
+ sqlite3_int64 szMax; /* Space allocated to aData */
+ unsigned char *aData; /* content of the file */
+ int nMmap; /* Number of memory mapped pages */
+ unsigned mFlags; /* Flags */
+ int eLock; /* Most recent lock against this file */
+};
+
+/*
+** Methods for MemFile
+*/
+static int memdbClose(sqlite3_file*);
+static int memdbRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
+static int memdbWrite(sqlite3_file*,const void*,int iAmt, sqlite3_int64 iOfst);
+static int memdbTruncate(sqlite3_file*, sqlite3_int64 size);
+static int memdbSync(sqlite3_file*, int flags);
+static int memdbFileSize(sqlite3_file*, sqlite3_int64 *pSize);
+static int memdbLock(sqlite3_file*, int);
+/* static int memdbCheckReservedLock(sqlite3_file*, int *pResOut);// not used */
+static int memdbFileControl(sqlite3_file*, int op, void *pArg);
+/* static int memdbSectorSize(sqlite3_file*); // not used */
+static int memdbDeviceCharacteristics(sqlite3_file*);
+static int memdbFetch(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
+static int memdbUnfetch(sqlite3_file*, sqlite3_int64 iOfst, void *p);
+
+/*
+** Methods for MemVfs
+*/
+static int memdbOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *);
+/* static int memdbDelete(sqlite3_vfs*, const char *zName, int syncDir); */
+static int memdbAccess(sqlite3_vfs*, const char *zName, int flags, int *);
+static int memdbFullPathname(sqlite3_vfs*, const char *zName, int, char *zOut);
+static void *memdbDlOpen(sqlite3_vfs*, const char *zFilename);
+static void memdbDlError(sqlite3_vfs*, int nByte, char *zErrMsg);
+static void (*memdbDlSym(sqlite3_vfs *pVfs, void *p, const char*zSym))(void);
+static void memdbDlClose(sqlite3_vfs*, void*);
+static int memdbRandomness(sqlite3_vfs*, int nByte, char *zOut);
+static int memdbSleep(sqlite3_vfs*, int microseconds);
+/* static int memdbCurrentTime(sqlite3_vfs*, double*); */
+static int memdbGetLastError(sqlite3_vfs*, int, char *);
+static int memdbCurrentTimeInt64(sqlite3_vfs*, sqlite3_int64*);
+
+static sqlite3_vfs memdb_vfs = {
+ 2, /* iVersion */
+ 0, /* szOsFile (set when registered) */
+ 1024, /* mxPathname */
+ 0, /* pNext */
+ "memdb", /* zName */
+ 0, /* pAppData (set when registered) */
+ memdbOpen, /* xOpen */
+ 0, /* memdbDelete, */ /* xDelete */
+ memdbAccess, /* xAccess */
+ memdbFullPathname, /* xFullPathname */
+ memdbDlOpen, /* xDlOpen */
+ memdbDlError, /* xDlError */
+ memdbDlSym, /* xDlSym */
+ memdbDlClose, /* xDlClose */
+ memdbRandomness, /* xRandomness */
+ memdbSleep, /* xSleep */
+ 0, /* memdbCurrentTime, */ /* xCurrentTime */
+ memdbGetLastError, /* xGetLastError */
+ memdbCurrentTimeInt64 /* xCurrentTimeInt64 */
+};
+
+static const sqlite3_io_methods memdb_io_methods = {
+ 3, /* iVersion */
+ memdbClose, /* xClose */
+ memdbRead, /* xRead */
+ memdbWrite, /* xWrite */
+ memdbTruncate, /* xTruncate */
+ memdbSync, /* xSync */
+ memdbFileSize, /* xFileSize */
+ memdbLock, /* xLock */
+ memdbLock, /* xUnlock - same as xLock in this case */
+ 0, /* memdbCheckReservedLock, */ /* xCheckReservedLock */
+ memdbFileControl, /* xFileControl */
+ 0, /* memdbSectorSize,*/ /* xSectorSize */
+ memdbDeviceCharacteristics, /* xDeviceCharacteristics */
+ 0, /* xShmMap */
+ 0, /* xShmLock */
+ 0, /* xShmBarrier */
+ 0, /* xShmUnmap */
+ memdbFetch, /* xFetch */
+ memdbUnfetch /* xUnfetch */
+};
+
+
+
+/*
+** Close an memdb-file.
+**
+** The pData pointer is owned by the application, so there is nothing
+** to free.
+*/
+static int memdbClose(sqlite3_file *pFile){
+ MemFile *p = (MemFile *)pFile;
+ if( p->mFlags & SQLITE_DESERIALIZE_FREEONCLOSE ) sqlite3_free(p->aData);
+ return SQLITE_OK;
+}
+
+/*
+** Read data from an memdb-file.
+*/
+static int memdbRead(
+ sqlite3_file *pFile,
+ void *zBuf,
+ int iAmt,
+ sqlite_int64 iOfst
+){
+ MemFile *p = (MemFile *)pFile;
+ if( iOfst+iAmt>p->sz ){
+ memset(zBuf, 0, iAmt);
+ if( iOfstsz ) memcpy(zBuf, p->aData+iOfst, p->sz - iOfst);
+ return SQLITE_IOERR_SHORT_READ;
+ }
+ memcpy(zBuf, p->aData+iOfst, iAmt);
+ return SQLITE_OK;
+}
+
+/*
+** Try to enlarge the memory allocation to hold at least sz bytes
+*/
+static int memdbEnlarge(MemFile *p, sqlite3_int64 newSz){
+ unsigned char *pNew;
+ if( (p->mFlags & SQLITE_DESERIALIZE_RESIZEABLE)==0 || p->nMmap>0 ){
+ return SQLITE_FULL;
+ }
+ pNew = sqlite3_realloc64(p->aData, newSz);
+ if( pNew==0 ) return SQLITE_NOMEM;
+ p->aData = pNew;
+ p->szMax = newSz;
+ return SQLITE_OK;
+}
+
+/*
+** Write data to an memdb-file.
+*/
+static int memdbWrite(
+ sqlite3_file *pFile,
+ const void *z,
+ int iAmt,
+ sqlite_int64 iOfst
+){
+ MemFile *p = (MemFile *)pFile;
+ if( iOfst+iAmt>p->sz ){
+ int rc;
+ if( iOfst+iAmt>p->szMax
+ && (rc = memdbEnlarge(p, (iOfst+iAmt)*2))!=SQLITE_OK
+ ){
+ return rc;
+ }
+ if( iOfst>p->sz ) memset(p->aData+p->sz, 0, iOfst-p->sz);
+ p->sz = iOfst+iAmt;
+ }
+ memcpy(p->aData+iOfst, z, iAmt);
+ return SQLITE_OK;
+}
+
+/*
+** Truncate an memdb-file.
+**
+** In rollback mode (which is always the case for memdb, as it does not
+** support WAL mode) the truncate() method is only used to reduce
+** the size of a file, never to increase the size.
+*/
+static int memdbTruncate(sqlite3_file *pFile, sqlite_int64 size){
+ MemFile *p = (MemFile *)pFile;
+ if( NEVER(size>p->sz) ) return SQLITE_FULL;
+ p->sz = size;
+ return SQLITE_OK;
+}
+
+/*
+** Sync an memdb-file.
+*/
+static int memdbSync(sqlite3_file *pFile, int flags){
+ return SQLITE_OK;
+}
+
+/*
+** Return the current file-size of an memdb-file.
+*/
+static int memdbFileSize(sqlite3_file *pFile, sqlite_int64 *pSize){
+ MemFile *p = (MemFile *)pFile;
+ *pSize = p->sz;
+ return SQLITE_OK;
+}
+
+/*
+** Lock an memdb-file.
+*/
+static int memdbLock(sqlite3_file *pFile, int eLock){
+ MemFile *p = (MemFile *)pFile;
+ p->eLock = eLock;
+ return SQLITE_OK;
+}
+
+#if 0 /* Never used because memdbAccess() always returns false */
+/*
+** Check if another file-handle holds a RESERVED lock on an memdb-file.
+*/
+static int memdbCheckReservedLock(sqlite3_file *pFile, int *pResOut){
+ *pResOut = 0;
+ return SQLITE_OK;
+}
+#endif
+
+/*
+** File control method. For custom operations on an memdb-file.
+*/
+static int memdbFileControl(sqlite3_file *pFile, int op, void *pArg){
+ MemFile *p = (MemFile *)pFile;
+ int rc = SQLITE_NOTFOUND;
+ if( op==SQLITE_FCNTL_VFSNAME ){
+ *(char**)pArg = sqlite3_mprintf("memdb(%p,%lld)", p->aData, p->sz);
+ rc = SQLITE_OK;
+ }
+ return rc;
+}
+
+#if 0 /* Not used because of SQLITE_IOCAP_POWERSAFE_OVERWRITE */
+/*
+** Return the sector-size in bytes for an memdb-file.
+*/
+static int memdbSectorSize(sqlite3_file *pFile){
+ return 1024;
+}
+#endif
+
+/*
+** Return the device characteristic flags supported by an memdb-file.
+*/
+static int memdbDeviceCharacteristics(sqlite3_file *pFile){
+ return SQLITE_IOCAP_ATOMIC |
+ SQLITE_IOCAP_POWERSAFE_OVERWRITE |
+ SQLITE_IOCAP_SAFE_APPEND |
+ SQLITE_IOCAP_SEQUENTIAL;
+}
+
+/* Fetch a page of a memory-mapped file */
+static int memdbFetch(
+ sqlite3_file *pFile,
+ sqlite3_int64 iOfst,
+ int iAmt,
+ void **pp
+){
+ MemFile *p = (MemFile *)pFile;
+ p->nMmap++;
+ *pp = (void*)(p->aData + iOfst);
+ return SQLITE_OK;
+}
+
+/* Release a memory-mapped page */
+static int memdbUnfetch(sqlite3_file *pFile, sqlite3_int64 iOfst, void *pPage){
+ MemFile *p = (MemFile *)pFile;
+ p->nMmap--;
+ return SQLITE_OK;
+}
+
+/*
+** Open an mem file handle.
+*/
+static int memdbOpen(
+ sqlite3_vfs *pVfs,
+ const char *zName,
+ sqlite3_file *pFile,
+ int flags,
+ int *pOutFlags
+){
+ MemFile *p = (MemFile*)pFile;
+ if( (flags & SQLITE_OPEN_MAIN_DB)==0 ){
+ return ORIGVFS(pVfs)->xOpen(ORIGVFS(pVfs), zName, pFile, flags, pOutFlags);
+ }
+ memset(p, 0, sizeof(*p));
+ p->mFlags = SQLITE_DESERIALIZE_RESIZEABLE | SQLITE_DESERIALIZE_FREEONCLOSE;
+ assert( pOutFlags!=0 ); /* True because flags==SQLITE_OPEN_MAIN_DB */
+ *pOutFlags = flags | SQLITE_OPEN_MEMORY;
+ p->base.pMethods = &memdb_io_methods;
+ return SQLITE_OK;
+}
+
+#if 0 /* Only used to delete rollback journals, master journals, and WAL
+ ** files, none of which exist in memdb. So this routine is never used */
+/*
+** Delete the file located at zPath. If the dirSync argument is true,
+** ensure the file-system modifications are synced to disk before
+** returning.
+*/
+static int memdbDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
+ return SQLITE_IOERR_DELETE;
+}
+#endif
+
+/*
+** Test for access permissions. Return true if the requested permission
+** is available, or false otherwise.
+**
+** With memdb, no files ever exist on disk. So always return false.
+*/
+static int memdbAccess(
+ sqlite3_vfs *pVfs,
+ const char *zPath,
+ int flags,
+ int *pResOut
+){
+ *pResOut = 0;
+ return SQLITE_OK;
+}
+
+/*
+** Populate buffer zOut with the full canonical pathname corresponding
+** to the pathname in zPath. zOut is guaranteed to point to a buffer
+** of at least (INST_MAX_PATHNAME+1) bytes.
+*/
+static int memdbFullPathname(
+ sqlite3_vfs *pVfs,
+ const char *zPath,
+ int nOut,
+ char *zOut
+){
+ sqlite3_snprintf(nOut, zOut, "%s", zPath);
+ return SQLITE_OK;
+}
+
+/*
+** Open the dynamic library located at zPath and return a handle.
+*/
+static void *memdbDlOpen(sqlite3_vfs *pVfs, const char *zPath){
+ return ORIGVFS(pVfs)->xDlOpen(ORIGVFS(pVfs), zPath);
+}
+
+/*
+** Populate the buffer zErrMsg (size nByte bytes) with a human readable
+** utf-8 string describing the most recent error encountered associated
+** with dynamic libraries.
+*/
+static void memdbDlError(sqlite3_vfs *pVfs, int nByte, char *zErrMsg){
+ ORIGVFS(pVfs)->xDlError(ORIGVFS(pVfs), nByte, zErrMsg);
+}
+
+/*
+** Return a pointer to the symbol zSymbol in the dynamic library pHandle.
+*/
+static void (*memdbDlSym(sqlite3_vfs *pVfs, void *p, const char *zSym))(void){
+ return ORIGVFS(pVfs)->xDlSym(ORIGVFS(pVfs), p, zSym);
+}
+
+/*
+** Close the dynamic library handle pHandle.
+*/
+static void memdbDlClose(sqlite3_vfs *pVfs, void *pHandle){
+ ORIGVFS(pVfs)->xDlClose(ORIGVFS(pVfs), pHandle);
+}
+
+/*
+** Populate the buffer pointed to by zBufOut with nByte bytes of
+** random data.
+*/
+static int memdbRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
+ return ORIGVFS(pVfs)->xRandomness(ORIGVFS(pVfs), nByte, zBufOut);
+}
+
+/*
+** Sleep for nMicro microseconds. Return the number of microseconds
+** actually slept.
+*/
+static int memdbSleep(sqlite3_vfs *pVfs, int nMicro){
+ return ORIGVFS(pVfs)->xSleep(ORIGVFS(pVfs), nMicro);
+}
+
+#if 0 /* Never used. Modern cores only call xCurrentTimeInt64() */
+/*
+** Return the current time as a Julian Day number in *pTimeOut.
+*/
+static int memdbCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
+ return ORIGVFS(pVfs)->xCurrentTime(ORIGVFS(pVfs), pTimeOut);
+}
+#endif
+
+static int memdbGetLastError(sqlite3_vfs *pVfs, int a, char *b){
+ return ORIGVFS(pVfs)->xGetLastError(ORIGVFS(pVfs), a, b);
+}
+static int memdbCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *p){
+ return ORIGVFS(pVfs)->xCurrentTimeInt64(ORIGVFS(pVfs), p);
+}
+
+/*
+** Translate a database connection pointer and schema name into a
+** MemFile pointer.
+*/
+static MemFile *memdbFromDbSchema(sqlite3 *db, const char *zSchema){
+ MemFile *p = 0;
+ int rc = sqlite3_file_control(db, zSchema, SQLITE_FCNTL_FILE_POINTER, &p);
+ if( rc ) return 0;
+ if( p->base.pMethods!=&memdb_io_methods ) return 0;
+ return p;
+}
+
+/*
+** Return the serialization of a database
+*/
+SQLITE_API unsigned char *sqlite3_serialize(
+ sqlite3 *db, /* The database connection */
+ const char *zSchema, /* Which database within the connection */
+ sqlite3_int64 *piSize, /* Write size here, if not NULL */
+ unsigned int mFlags /* Maybe SQLITE_SERIALIZE_NOCOPY */
+){
+ MemFile *p;
+ int iDb;
+ Btree *pBt;
+ sqlite3_int64 sz;
+ int szPage = 0;
+ sqlite3_stmt *pStmt = 0;
+ unsigned char *pOut;
+ char *zSql;
+ int rc;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) ){
+ (void)SQLITE_MISUSE_BKPT;
+ return 0;
+ }
+#endif
+
+ if( zSchema==0 ) zSchema = db->aDb[0].zDbSName;
+ p = memdbFromDbSchema(db, zSchema);
+ iDb = sqlite3FindDbName(db, zSchema);
+ if( piSize ) *piSize = -1;
+ if( iDb<0 ) return 0;
+ if( p ){
+ if( piSize ) *piSize = p->sz;
+ if( mFlags & SQLITE_SERIALIZE_NOCOPY ){
+ pOut = p->aData;
+ }else{
+ pOut = sqlite3_malloc64( p->sz );
+ if( pOut ) memcpy(pOut, p->aData, p->sz);
+ }
+ return pOut;
+ }
+ pBt = db->aDb[iDb].pBt;
+ if( pBt==0 ) return 0;
+ szPage = sqlite3BtreeGetPageSize(pBt);
+ zSql = sqlite3_mprintf("PRAGMA \"%w\".page_count", zSchema);
+ rc = zSql ? sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0) : SQLITE_NOMEM;
+ sqlite3_free(zSql);
+ if( rc ) return 0;
+ rc = sqlite3_step(pStmt);
+ if( rc!=SQLITE_ROW ){
+ pOut = 0;
+ }else{
+ sz = sqlite3_column_int64(pStmt, 0)*szPage;
+ if( piSize ) *piSize = sz;
+ if( mFlags & SQLITE_SERIALIZE_NOCOPY ){
+ pOut = 0;
+ }else{
+ pOut = sqlite3_malloc64( sz );
+ if( pOut ){
+ int nPage = sqlite3_column_int(pStmt, 0);
+ Pager *pPager = sqlite3BtreePager(pBt);
+ int pgno;
+ for(pgno=1; pgno<=nPage; pgno++){
+ DbPage *pPage = 0;
+ unsigned char *pTo = pOut + szPage*(sqlite3_int64)(pgno-1);
+ rc = sqlite3PagerGet(pPager, pgno, (DbPage**)&pPage, 0);
+ if( rc==SQLITE_OK ){
+ memcpy(pTo, sqlite3PagerGetData(pPage), szPage);
+ }else{
+ memset(pTo, 0, szPage);
+ }
+ sqlite3PagerUnref(pPage);
+ }
+ }
+ }
+ }
+ sqlite3_finalize(pStmt);
+ return pOut;
+}
+
+/* Convert zSchema to a MemDB and initialize its content.
+*/
+SQLITE_API int sqlite3_deserialize(
+ sqlite3 *db, /* The database connection */
+ const char *zSchema, /* Which DB to reopen with the deserialization */
+ unsigned char *pData, /* The serialized database content */
+ sqlite3_int64 szDb, /* Number bytes in the deserialization */
+ sqlite3_int64 szBuf, /* Total size of buffer pData[] */
+ unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */
+){
+ MemFile *p;
+ char *zSql;
+ sqlite3_stmt *pStmt = 0;
+ int rc;
+ int iDb;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) ){
+ return SQLITE_MISUSE_BKPT;
+ }
+ if( szDb<0 ) return SQLITE_MISUSE_BKPT;
+ if( szBuf<0 ) return SQLITE_MISUSE_BKPT;
+#endif
+
+ sqlite3_mutex_enter(db->mutex);
+ if( zSchema==0 ) zSchema = db->aDb[0].zDbSName;
+ iDb = sqlite3FindDbName(db, zSchema);
+ if( iDb<0 ){
+ rc = SQLITE_ERROR;
+ goto end_deserialize;
+ }
+ zSql = sqlite3_mprintf("ATTACH x AS %Q", zSchema);
+ rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+ sqlite3_free(zSql);
+ if( rc ) goto end_deserialize;
+ db->init.iDb = (u8)iDb;
+ db->init.reopenMemdb = 1;
+ rc = sqlite3_step(pStmt);
+ db->init.reopenMemdb = 0;
+ if( rc!=SQLITE_DONE ){
+ rc = SQLITE_ERROR;
+ goto end_deserialize;
+ }
+ p = memdbFromDbSchema(db, zSchema);
+ if( p==0 ){
+ rc = SQLITE_ERROR;
+ }else{
+ p->aData = pData;
+ p->sz = szDb;
+ p->szMax = szBuf;
+ p->mFlags = mFlags;
+ rc = SQLITE_OK;
+ }
+
+end_deserialize:
+ sqlite3_finalize(pStmt);
+ sqlite3_mutex_leave(db->mutex);
+ return rc;
+}
+
+/*
+** This routine is called when the extension is loaded.
+** Register the new VFS.
+*/
+SQLITE_PRIVATE int sqlite3MemdbInit(void){
+ sqlite3_vfs *pLower = sqlite3_vfs_find(0);
+ int sz = pLower->szOsFile;
+ memdb_vfs.pAppData = pLower;
+ /* In all known configurations of SQLite, the size of a default
+ ** sqlite3_file is greater than the size of a memdb sqlite3_file.
+ ** Should that ever change, remove the following NEVER() */
+ if( NEVER(szBITVEC_NBIT and iDivisor==0 then Bitvec.u.aHash[] is
+** a hash table that will hold up to BITVEC_MXHASH distinct values.
+**
+** Otherwise, the value i is redirected into one of BITVEC_NPTR
+** sub-bitmaps pointed to by Bitvec.u.apSub[]. Each subbitmap
+** handles up to iDivisor separate values of i. apSub[0] holds
+** values between 1 and iDivisor. apSub[1] holds values between
+** iDivisor+1 and 2*iDivisor. apSub[N] holds values between
+** N*iDivisor+1 and (N+1)*iDivisor. Each subbitmap is normalized
+** to hold deal with values between 1 and iDivisor.
+*/
+struct Bitvec {
+ u32 iSize; /* Maximum bit index. Max iSize is 4,294,967,296. */
+ u32 nSet; /* Number of bits that are set - only valid for aHash
+ ** element. Max is BITVEC_NINT. For BITVEC_SZ of 512,
+ ** this would be 125. */
+ u32 iDivisor; /* Number of bits handled by each apSub[] entry. */
+ /* Should >=0 for apSub element. */
+ /* Max iDivisor is max(u32) / BITVEC_NPTR + 1. */
+ /* For a BITVEC_SZ of 512, this would be 34,359,739. */
+ union {
+ BITVEC_TELEM aBitmap[BITVEC_NELEM]; /* Bitmap representation */
+ u32 aHash[BITVEC_NINT]; /* Hash table representation */
+ Bitvec *apSub[BITVEC_NPTR]; /* Recursive representation */
+ } u;
+};
+
+/*
+** Create a new bitmap object able to handle bits between 0 and iSize,
+** inclusive. Return a pointer to the new object. Return NULL if
+** malloc fails.
+*/
+SQLITE_PRIVATE Bitvec *sqlite3BitvecCreate(u32 iSize){
+ Bitvec *p;
+ assert( sizeof(*p)==BITVEC_SZ );
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p ){
+ p->iSize = iSize;
+ }
+ return p;
+}
+
+/*
+** Check to see if the i-th bit is set. Return true or false.
+** If p is NULL (if the bitmap has not been created) or if
+** i is out of range, then return false.
+*/
+SQLITE_PRIVATE int sqlite3BitvecTestNotNull(Bitvec *p, u32 i){
+ assert( p!=0 );
+ i--;
+ if( i>=p->iSize ) return 0;
+ while( p->iDivisor ){
+ u32 bin = i/p->iDivisor;
+ i = i%p->iDivisor;
+ p = p->u.apSub[bin];
+ if (!p) {
+ return 0;
+ }
+ }
+ if( p->iSize<=BITVEC_NBIT ){
+ return (p->u.aBitmap[i/BITVEC_SZELEM] & (1<<(i&(BITVEC_SZELEM-1))))!=0;
+ } else{
+ u32 h = BITVEC_HASH(i++);
+ while( p->u.aHash[h] ){
+ if( p->u.aHash[h]==i ) return 1;
+ h = (h+1) % BITVEC_NINT;
+ }
+ return 0;
+ }
+}
+SQLITE_PRIVATE int sqlite3BitvecTest(Bitvec *p, u32 i){
+ return p!=0 && sqlite3BitvecTestNotNull(p,i);
+}
+
+/*
+** Set the i-th bit. Return 0 on success and an error code if
+** anything goes wrong.
+**
+** This routine might cause sub-bitmaps to be allocated. Failing
+** to get the memory needed to hold the sub-bitmap is the only
+** that can go wrong with an insert, assuming p and i are valid.
+**
+** The calling function must ensure that p is a valid Bitvec object
+** and that the value for "i" is within range of the Bitvec object.
+** Otherwise the behavior is undefined.
+*/
+SQLITE_PRIVATE int sqlite3BitvecSet(Bitvec *p, u32 i){
+ u32 h;
+ if( p==0 ) return SQLITE_OK;
+ assert( i>0 );
+ assert( i<=p->iSize );
+ i--;
+ while((p->iSize > BITVEC_NBIT) && p->iDivisor) {
+ u32 bin = i/p->iDivisor;
+ i = i%p->iDivisor;
+ if( p->u.apSub[bin]==0 ){
+ p->u.apSub[bin] = sqlite3BitvecCreate( p->iDivisor );
+ if( p->u.apSub[bin]==0 ) return SQLITE_NOMEM_BKPT;
+ }
+ p = p->u.apSub[bin];
+ }
+ if( p->iSize<=BITVEC_NBIT ){
+ p->u.aBitmap[i/BITVEC_SZELEM] |= 1 << (i&(BITVEC_SZELEM-1));
+ return SQLITE_OK;
+ }
+ h = BITVEC_HASH(i++);
+ /* if there wasn't a hash collision, and this doesn't */
+ /* completely fill the hash, then just add it without */
+ /* worring about sub-dividing and re-hashing. */
+ if( !p->u.aHash[h] ){
+ if (p->nSet<(BITVEC_NINT-1)) {
+ goto bitvec_set_end;
+ } else {
+ goto bitvec_set_rehash;
+ }
+ }
+ /* there was a collision, check to see if it's already */
+ /* in hash, if not, try to find a spot for it */
+ do {
+ if( p->u.aHash[h]==i ) return SQLITE_OK;
+ h++;
+ if( h>=BITVEC_NINT ) h = 0;
+ } while( p->u.aHash[h] );
+ /* we didn't find it in the hash. h points to the first */
+ /* available free spot. check to see if this is going to */
+ /* make our hash too "full". */
+bitvec_set_rehash:
+ if( p->nSet>=BITVEC_MXHASH ){
+ unsigned int j;
+ int rc;
+ u32 *aiValues = sqlite3StackAllocRaw(0, sizeof(p->u.aHash));
+ if( aiValues==0 ){
+ return SQLITE_NOMEM_BKPT;
+ }else{
+ memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
+ memset(p->u.apSub, 0, sizeof(p->u.apSub));
+ p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
+ rc = sqlite3BitvecSet(p, i);
+ for(j=0; jnSet++;
+ p->u.aHash[h] = i;
+ return SQLITE_OK;
+}
+
+/*
+** Clear the i-th bit.
+**
+** pBuf must be a pointer to at least BITVEC_SZ bytes of temporary storage
+** that BitvecClear can use to rebuilt its hash table.
+*/
+SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec *p, u32 i, void *pBuf){
+ if( p==0 ) return;
+ assert( i>0 );
+ i--;
+ while( p->iDivisor ){
+ u32 bin = i/p->iDivisor;
+ i = i%p->iDivisor;
+ p = p->u.apSub[bin];
+ if (!p) {
+ return;
+ }
+ }
+ if( p->iSize<=BITVEC_NBIT ){
+ p->u.aBitmap[i/BITVEC_SZELEM] &= ~(1 << (i&(BITVEC_SZELEM-1)));
+ }else{
+ unsigned int j;
+ u32 *aiValues = pBuf;
+ memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
+ memset(p->u.aHash, 0, sizeof(p->u.aHash));
+ p->nSet = 0;
+ for(j=0; jnSet++;
+ while( p->u.aHash[h] ){
+ h++;
+ if( h>=BITVEC_NINT ) h = 0;
+ }
+ p->u.aHash[h] = aiValues[j];
+ }
+ }
+ }
+}
+
+/*
+** Destroy a bitmap object. Reclaim all memory used.
+*/
+SQLITE_PRIVATE void sqlite3BitvecDestroy(Bitvec *p){
+ if( p==0 ) return;
+ if( p->iDivisor ){
+ unsigned int i;
+ for(i=0; iu.apSub[i]);
+ }
+ }
+ sqlite3_free(p);
+}
+
+/*
+** Return the value of the iSize parameter specified when Bitvec *p
+** was created.
+*/
+SQLITE_PRIVATE u32 sqlite3BitvecSize(Bitvec *p){
+ return p->iSize;
+}
+
+#ifndef SQLITE_UNTESTABLE
+/*
+** Let V[] be an array of unsigned characters sufficient to hold
+** up to N bits. Let I be an integer between 0 and N. 0<=I>3] |= (1<<(I&7))
+#define CLEARBIT(V,I) V[I>>3] &= ~(1<<(I&7))
+#define TESTBIT(V,I) (V[I>>3]&(1<<(I&7)))!=0
+
+/*
+** This routine runs an extensive test of the Bitvec code.
+**
+** The input is an array of integers that acts as a program
+** to test the Bitvec. The integers are opcodes followed
+** by 0, 1, or 3 operands, depending on the opcode. Another
+** opcode follows immediately after the last operand.
+**
+** There are 6 opcodes numbered from 0 through 5. 0 is the
+** "halt" opcode and causes the test to end.
+**
+** 0 Halt and return the number of errors
+** 1 N S X Set N bits beginning with S and incrementing by X
+** 2 N S X Clear N bits beginning with S and incrementing by X
+** 3 N Set N randomly chosen bits
+** 4 N Clear N randomly chosen bits
+** 5 N S X Set N bits from S increment X in array only, not in bitvec
+**
+** The opcodes 1 through 4 perform set and clear operations are performed
+** on both a Bitvec object and on a linear array of bits obtained from malloc.
+** Opcode 5 works on the linear array only, not on the Bitvec.
+** Opcode 5 is used to deliberately induce a fault in order to
+** confirm that error detection works.
+**
+** At the conclusion of the test the linear array is compared
+** against the Bitvec object. If there are any differences,
+** an error is returned. If they are the same, zero is returned.
+**
+** If a memory allocation error occurs, return -1.
+*/
+SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int sz, int *aOp){
+ Bitvec *pBitvec = 0;
+ unsigned char *pV = 0;
+ int rc = -1;
+ int i, nx, pc, op;
+ void *pTmpSpace;
+
+ /* Allocate the Bitvec to be tested and a linear array of
+ ** bits to act as the reference */
+ pBitvec = sqlite3BitvecCreate( sz );
+ pV = sqlite3MallocZero( (sz+7)/8 + 1 );
+ pTmpSpace = sqlite3_malloc64(BITVEC_SZ);
+ if( pBitvec==0 || pV==0 || pTmpSpace==0 ) goto bitvec_end;
+
+ /* NULL pBitvec tests */
+ sqlite3BitvecSet(0, 1);
+ sqlite3BitvecClear(0, 1, pTmpSpace);
+
+ /* Run the program */
+ pc = 0;
+ while( (op = aOp[pc])!=0 ){
+ switch( op ){
+ case 1:
+ case 2:
+ case 5: {
+ nx = 4;
+ i = aOp[pc+2] - 1;
+ aOp[pc+2] += aOp[pc+3];
+ break;
+ }
+ case 3:
+ case 4:
+ default: {
+ nx = 2;
+ sqlite3_randomness(sizeof(i), &i);
+ break;
+ }
+ }
+ if( (--aOp[pc+1]) > 0 ) nx = 0;
+ pc += nx;
+ i = (i & 0x7fffffff)%sz;
+ if( (op & 1)!=0 ){
+ SETBIT(pV, (i+1));
+ if( op!=5 ){
+ if( sqlite3BitvecSet(pBitvec, i+1) ) goto bitvec_end;
+ }
+ }else{
+ CLEARBIT(pV, (i+1));
+ sqlite3BitvecClear(pBitvec, i+1, pTmpSpace);
+ }
+ }
+
+ /* Test to make sure the linear array exactly matches the
+ ** Bitvec object. Start with the assumption that they do
+ ** match (rc==0). Change rc to non-zero if a discrepancy
+ ** is found.
+ */
+ rc = sqlite3BitvecTest(0,0) + sqlite3BitvecTest(pBitvec, sz+1)
+ + sqlite3BitvecTest(pBitvec, 0)
+ + (sqlite3BitvecSize(pBitvec) - sz);
+ for(i=1; i<=sz; i++){
+ if( (TESTBIT(pV,i))!=sqlite3BitvecTest(pBitvec,i) ){
+ rc = i;
+ break;
+ }
+ }
+
+ /* Free allocated structure */
+bitvec_end:
+ sqlite3_free(pTmpSpace);
+ sqlite3_free(pV);
+ sqlite3BitvecDestroy(pBitvec);
+ return rc;
+}
+#endif /* SQLITE_UNTESTABLE */
+
+/************** End of bitvec.c **********************************************/
+/************** Begin file pcache.c ******************************************/
+/*
+** 2008 August 05
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file implements that page cache.
+*/
+/* #include "sqliteInt.h" */
+
+/*
+** A complete page cache is an instance of this structure. Every
+** entry in the cache holds a single page of the database file. The
+** btree layer only operates on the cached copy of the database pages.
+**
+** A page cache entry is "clean" if it exactly matches what is currently
+** on disk. A page is "dirty" if it has been modified and needs to be
+** persisted to disk.
+**
+** pDirty, pDirtyTail, pSynced:
+** All dirty pages are linked into the doubly linked list using
+** PgHdr.pDirtyNext and pDirtyPrev. The list is maintained in LRU order
+** such that p was added to the list more recently than p->pDirtyNext.
+** PCache.pDirty points to the first (newest) element in the list and
+** pDirtyTail to the last (oldest).
+**
+** The PCache.pSynced variable is used to optimize searching for a dirty
+** page to eject from the cache mid-transaction. It is better to eject
+** a page that does not require a journal sync than one that does.
+** Therefore, pSynced is maintained to that it *almost* always points
+** to either the oldest page in the pDirty/pDirtyTail list that has a
+** clear PGHDR_NEED_SYNC flag or to a page that is older than this one
+** (so that the right page to eject can be found by following pDirtyPrev
+** pointers).
+*/
+struct PCache {
+ PgHdr *pDirty, *pDirtyTail; /* List of dirty pages in LRU order */
+ PgHdr *pSynced; /* Last synced page in dirty page list */
+ int nRefSum; /* Sum of ref counts over all pages */
+ int szCache; /* Configured cache size */
+ int szSpill; /* Size before spilling occurs */
+ int szPage; /* Size of every page in this cache */
+ int szExtra; /* Size of extra space for each page */
+ u8 bPurgeable; /* True if pages are on backing store */
+ u8 eCreate; /* eCreate value for for xFetch() */
+ int (*xStress)(void*,PgHdr*); /* Call to try make a page clean */
+ void *pStress; /* Argument to xStress */
+ sqlite3_pcache *pCache; /* Pluggable cache module */
+};
+
+/********************************** Test and Debug Logic **********************/
+/*
+** Debug tracing macros. Enable by by changing the "0" to "1" and
+** recompiling.
+**
+** When sqlite3PcacheTrace is 1, single line trace messages are issued.
+** When sqlite3PcacheTrace is 2, a dump of the pcache showing all cache entries
+** is displayed for many operations, resulting in a lot of output.
+*/
+#if defined(SQLITE_DEBUG) && 0
+ int sqlite3PcacheTrace = 2; /* 0: off 1: simple 2: cache dumps */
+ int sqlite3PcacheMxDump = 9999; /* Max cache entries for pcacheDump() */
+# define pcacheTrace(X) if(sqlite3PcacheTrace){sqlite3DebugPrintf X;}
+ void pcacheDump(PCache *pCache){
+ int N;
+ int i, j;
+ sqlite3_pcache_page *pLower;
+ PgHdr *pPg;
+ unsigned char *a;
+
+ if( sqlite3PcacheTrace<2 ) return;
+ if( pCache->pCache==0 ) return;
+ N = sqlite3PcachePagecount(pCache);
+ if( N>sqlite3PcacheMxDump ) N = sqlite3PcacheMxDump;
+ for(i=1; i<=N; i++){
+ pLower = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, i, 0);
+ if( pLower==0 ) continue;
+ pPg = (PgHdr*)pLower->pExtra;
+ printf("%3d: nRef %2d flgs %02x data ", i, pPg->nRef, pPg->flags);
+ a = (unsigned char *)pLower->pBuf;
+ for(j=0; j<12; j++) printf("%02x", a[j]);
+ printf("\n");
+ if( pPg->pPage==0 ){
+ sqlite3GlobalConfig.pcache2.xUnpin(pCache->pCache, pLower, 0);
+ }
+ }
+ }
+ #else
+# define pcacheTrace(X)
+# define pcacheDump(X)
+#endif
+
+/*
+** Check invariants on a PgHdr entry. Return true if everything is OK.
+** Return false if any invariant is violated.
+**
+** This routine is for use inside of assert() statements only. For
+** example:
+**
+** assert( sqlite3PcachePageSanity(pPg) );
+*/
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3PcachePageSanity(PgHdr *pPg){
+ PCache *pCache;
+ assert( pPg!=0 );
+ assert( pPg->pgno>0 || pPg->pPager==0 ); /* Page number is 1 or more */
+ pCache = pPg->pCache;
+ assert( pCache!=0 ); /* Every page has an associated PCache */
+ if( pPg->flags & PGHDR_CLEAN ){
+ assert( (pPg->flags & PGHDR_DIRTY)==0 );/* Cannot be both CLEAN and DIRTY */
+ assert( pCache->pDirty!=pPg ); /* CLEAN pages not on dirty list */
+ assert( pCache->pDirtyTail!=pPg );
+ }
+ /* WRITEABLE pages must also be DIRTY */
+ if( pPg->flags & PGHDR_WRITEABLE ){
+ assert( pPg->flags & PGHDR_DIRTY ); /* WRITEABLE implies DIRTY */
+ }
+ /* NEED_SYNC can be set independently of WRITEABLE. This can happen,
+ ** for example, when using the sqlite3PagerDontWrite() optimization:
+ ** (1) Page X is journalled, and gets WRITEABLE and NEED_SEEK.
+ ** (2) Page X moved to freelist, WRITEABLE is cleared
+ ** (3) Page X reused, WRITEABLE is set again
+ ** If NEED_SYNC had been cleared in step 2, then it would not be reset
+ ** in step 3, and page might be written into the database without first
+ ** syncing the rollback journal, which might cause corruption on a power
+ ** loss.
+ **
+ ** Another example is when the database page size is smaller than the
+ ** disk sector size. When any page of a sector is journalled, all pages
+ ** in that sector are marked NEED_SYNC even if they are still CLEAN, just
+ ** in case they are later modified, since all pages in the same sector
+ ** must be journalled and synced before any of those pages can be safely
+ ** written.
+ */
+ return 1;
+}
+#endif /* SQLITE_DEBUG */
+
+
+/********************************** Linked List Management ********************/
+
+/* Allowed values for second argument to pcacheManageDirtyList() */
+#define PCACHE_DIRTYLIST_REMOVE 1 /* Remove pPage from dirty list */
+#define PCACHE_DIRTYLIST_ADD 2 /* Add pPage to the dirty list */
+#define PCACHE_DIRTYLIST_FRONT 3 /* Move pPage to the front of the list */
+
+/*
+** Manage pPage's participation on the dirty list. Bits of the addRemove
+** argument determines what operation to do. The 0x01 bit means first
+** remove pPage from the dirty list. The 0x02 means add pPage back to
+** the dirty list. Doing both moves pPage to the front of the dirty list.
+*/
+static void pcacheManageDirtyList(PgHdr *pPage, u8 addRemove){
+ PCache *p = pPage->pCache;
+
+ pcacheTrace(("%p.DIRTYLIST.%s %d\n", p,
+ addRemove==1 ? "REMOVE" : addRemove==2 ? "ADD" : "FRONT",
+ pPage->pgno));
+ if( addRemove & PCACHE_DIRTYLIST_REMOVE ){
+ assert( pPage->pDirtyNext || pPage==p->pDirtyTail );
+ assert( pPage->pDirtyPrev || pPage==p->pDirty );
+
+ /* Update the PCache1.pSynced variable if necessary. */
+ if( p->pSynced==pPage ){
+ p->pSynced = pPage->pDirtyPrev;
+ }
+
+ if( pPage->pDirtyNext ){
+ pPage->pDirtyNext->pDirtyPrev = pPage->pDirtyPrev;
+ }else{
+ assert( pPage==p->pDirtyTail );
+ p->pDirtyTail = pPage->pDirtyPrev;
+ }
+ if( pPage->pDirtyPrev ){
+ pPage->pDirtyPrev->pDirtyNext = pPage->pDirtyNext;
+ }else{
+ /* If there are now no dirty pages in the cache, set eCreate to 2.
+ ** This is an optimization that allows sqlite3PcacheFetch() to skip
+ ** searching for a dirty page to eject from the cache when it might
+ ** otherwise have to. */
+ assert( pPage==p->pDirty );
+ p->pDirty = pPage->pDirtyNext;
+ assert( p->bPurgeable || p->eCreate==2 );
+ if( p->pDirty==0 ){ /*OPTIMIZATION-IF-TRUE*/
+ assert( p->bPurgeable==0 || p->eCreate==1 );
+ p->eCreate = 2;
+ }
+ }
+ }
+ if( addRemove & PCACHE_DIRTYLIST_ADD ){
+ pPage->pDirtyPrev = 0;
+ pPage->pDirtyNext = p->pDirty;
+ if( pPage->pDirtyNext ){
+ assert( pPage->pDirtyNext->pDirtyPrev==0 );
+ pPage->pDirtyNext->pDirtyPrev = pPage;
+ }else{
+ p->pDirtyTail = pPage;
+ if( p->bPurgeable ){
+ assert( p->eCreate==2 );
+ p->eCreate = 1;
+ }
+ }
+ p->pDirty = pPage;
+
+ /* If pSynced is NULL and this page has a clear NEED_SYNC flag, set
+ ** pSynced to point to it. Checking the NEED_SYNC flag is an
+ ** optimization, as if pSynced points to a page with the NEED_SYNC
+ ** flag set sqlite3PcacheFetchStress() searches through all newer
+ ** entries of the dirty-list for a page with NEED_SYNC clear anyway. */
+ if( !p->pSynced
+ && 0==(pPage->flags&PGHDR_NEED_SYNC) /*OPTIMIZATION-IF-FALSE*/
+ ){
+ p->pSynced = pPage;
+ }
+ }
+ pcacheDump(p);
+}
+
+/*
+** Wrapper around the pluggable caches xUnpin method. If the cache is
+** being used for an in-memory database, this function is a no-op.
+*/
+static void pcacheUnpin(PgHdr *p){
+ if( p->pCache->bPurgeable ){
+ pcacheTrace(("%p.UNPIN %d\n", p->pCache, p->pgno));
+ sqlite3GlobalConfig.pcache2.xUnpin(p->pCache->pCache, p->pPage, 0);
+ pcacheDump(p->pCache);
+ }
+}
+
+/*
+** Compute the number of pages of cache requested. p->szCache is the
+** cache size requested by the "PRAGMA cache_size" statement.
+*/
+static int numberOfCachePages(PCache *p){
+ if( p->szCache>=0 ){
+ /* IMPLEMENTATION-OF: R-42059-47211 If the argument N is positive then the
+ ** suggested cache size is set to N. */
+ return p->szCache;
+ }else{
+ /* IMPLEMENTATION-OF: R-61436-13639 If the argument N is negative, then
+ ** the number of cache pages is adjusted to use approximately abs(N*1024)
+ ** bytes of memory. */
+ return (int)((-1024*(i64)p->szCache)/(p->szPage+p->szExtra));
+ }
+}
+
+/*************************************************** General Interfaces ******
+**
+** Initialize and shutdown the page cache subsystem. Neither of these
+** functions are threadsafe.
+*/
+SQLITE_PRIVATE int sqlite3PcacheInitialize(void){
+ if( sqlite3GlobalConfig.pcache2.xInit==0 ){
+ /* IMPLEMENTATION-OF: R-26801-64137 If the xInit() method is NULL, then the
+ ** built-in default page cache is used instead of the application defined
+ ** page cache. */
+ sqlite3PCacheSetDefault();
+ }
+ return sqlite3GlobalConfig.pcache2.xInit(sqlite3GlobalConfig.pcache2.pArg);
+}
+SQLITE_PRIVATE void sqlite3PcacheShutdown(void){
+ if( sqlite3GlobalConfig.pcache2.xShutdown ){
+ /* IMPLEMENTATION-OF: R-26000-56589 The xShutdown() method may be NULL. */
+ sqlite3GlobalConfig.pcache2.xShutdown(sqlite3GlobalConfig.pcache2.pArg);
+ }
+}
+
+/*
+** Return the size in bytes of a PCache object.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSize(void){ return sizeof(PCache); }
+
+/*
+** Create a new PCache object. Storage space to hold the object
+** has already been allocated and is passed in as the p pointer.
+** The caller discovers how much space needs to be allocated by
+** calling sqlite3PcacheSize().
+**
+** szExtra is some extra space allocated for each page. The first
+** 8 bytes of the extra space will be zeroed as the page is allocated,
+** but remaining content will be uninitialized. Though it is opaque
+** to this module, the extra space really ends up being the MemPage
+** structure in the pager.
+*/
+SQLITE_PRIVATE int sqlite3PcacheOpen(
+ int szPage, /* Size of every page */
+ int szExtra, /* Extra space associated with each page */
+ int bPurgeable, /* True if pages are on backing store */
+ int (*xStress)(void*,PgHdr*),/* Call to try to make pages clean */
+ void *pStress, /* Argument to xStress */
+ PCache *p /* Preallocated space for the PCache */
+){
+ memset(p, 0, sizeof(PCache));
+ p->szPage = 1;
+ p->szExtra = szExtra;
+ assert( szExtra>=8 ); /* First 8 bytes will be zeroed */
+ p->bPurgeable = bPurgeable;
+ p->eCreate = 2;
+ p->xStress = xStress;
+ p->pStress = pStress;
+ p->szCache = 100;
+ p->szSpill = 1;
+ pcacheTrace(("%p.OPEN szPage %d bPurgeable %d\n",p,szPage,bPurgeable));
+ return sqlite3PcacheSetPageSize(p, szPage);
+}
+
+/*
+** Change the page size for PCache object. The caller must ensure that there
+** are no outstanding page references when this function is called.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSetPageSize(PCache *pCache, int szPage){
+ assert( pCache->nRefSum==0 && pCache->pDirty==0 );
+ if( pCache->szPage ){
+ sqlite3_pcache *pNew;
+ pNew = sqlite3GlobalConfig.pcache2.xCreate(
+ szPage, pCache->szExtra + ROUND8(sizeof(PgHdr)),
+ pCache->bPurgeable
+ );
+ if( pNew==0 ) return SQLITE_NOMEM_BKPT;
+ sqlite3GlobalConfig.pcache2.xCachesize(pNew, numberOfCachePages(pCache));
+ if( pCache->pCache ){
+ sqlite3GlobalConfig.pcache2.xDestroy(pCache->pCache);
+ }
+ pCache->pCache = pNew;
+ pCache->szPage = szPage;
+ pcacheTrace(("%p.PAGESIZE %d\n",pCache,szPage));
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Try to obtain a page from the cache.
+**
+** This routine returns a pointer to an sqlite3_pcache_page object if
+** such an object is already in cache, or if a new one is created.
+** This routine returns a NULL pointer if the object was not in cache
+** and could not be created.
+**
+** The createFlags should be 0 to check for existing pages and should
+** be 3 (not 1, but 3) to try to create a new page.
+**
+** If the createFlag is 0, then NULL is always returned if the page
+** is not already in the cache. If createFlag is 1, then a new page
+** is created only if that can be done without spilling dirty pages
+** and without exceeding the cache size limit.
+**
+** The caller needs to invoke sqlite3PcacheFetchFinish() to properly
+** initialize the sqlite3_pcache_page object and convert it into a
+** PgHdr object. The sqlite3PcacheFetch() and sqlite3PcacheFetchFinish()
+** routines are split this way for performance reasons. When separated
+** they can both (usually) operate without having to push values to
+** the stack on entry and pop them back off on exit, which saves a
+** lot of pushing and popping.
+*/
+SQLITE_PRIVATE sqlite3_pcache_page *sqlite3PcacheFetch(
+ PCache *pCache, /* Obtain the page from this cache */
+ Pgno pgno, /* Page number to obtain */
+ int createFlag /* If true, create page if it does not exist already */
+){
+ int eCreate;
+ sqlite3_pcache_page *pRes;
+
+ assert( pCache!=0 );
+ assert( pCache->pCache!=0 );
+ assert( createFlag==3 || createFlag==0 );
+ assert( pCache->eCreate==((pCache->bPurgeable && pCache->pDirty) ? 1 : 2) );
+
+ /* eCreate defines what to do if the page does not exist.
+ ** 0 Do not allocate a new page. (createFlag==0)
+ ** 1 Allocate a new page if doing so is inexpensive.
+ ** (createFlag==1 AND bPurgeable AND pDirty)
+ ** 2 Allocate a new page even it doing so is difficult.
+ ** (createFlag==1 AND !(bPurgeable AND pDirty)
+ */
+ eCreate = createFlag & pCache->eCreate;
+ assert( eCreate==0 || eCreate==1 || eCreate==2 );
+ assert( createFlag==0 || pCache->eCreate==eCreate );
+ assert( createFlag==0 || eCreate==1+(!pCache->bPurgeable||!pCache->pDirty) );
+ pRes = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, eCreate);
+ pcacheTrace(("%p.FETCH %d%s (result: %p)\n",pCache,pgno,
+ createFlag?" create":"",pRes));
+ return pRes;
+}
+
+/*
+** If the sqlite3PcacheFetch() routine is unable to allocate a new
+** page because no clean pages are available for reuse and the cache
+** size limit has been reached, then this routine can be invoked to
+** try harder to allocate a page. This routine might invoke the stress
+** callback to spill dirty pages to the journal. It will then try to
+** allocate the new page and will only fail to allocate a new page on
+** an OOM error.
+**
+** This routine should be invoked only after sqlite3PcacheFetch() fails.
+*/
+SQLITE_PRIVATE int sqlite3PcacheFetchStress(
+ PCache *pCache, /* Obtain the page from this cache */
+ Pgno pgno, /* Page number to obtain */
+ sqlite3_pcache_page **ppPage /* Write result here */
+){
+ PgHdr *pPg;
+ if( pCache->eCreate==2 ) return 0;
+
+ if( sqlite3PcachePagecount(pCache)>pCache->szSpill ){
+ /* Find a dirty page to write-out and recycle. First try to find a
+ ** page that does not require a journal-sync (one with PGHDR_NEED_SYNC
+ ** cleared), but if that is not possible settle for any other
+ ** unreferenced dirty page.
+ **
+ ** If the LRU page in the dirty list that has a clear PGHDR_NEED_SYNC
+ ** flag is currently referenced, then the following may leave pSynced
+ ** set incorrectly (pointing to other than the LRU page with NEED_SYNC
+ ** cleared). This is Ok, as pSynced is just an optimization. */
+ for(pPg=pCache->pSynced;
+ pPg && (pPg->nRef || (pPg->flags&PGHDR_NEED_SYNC));
+ pPg=pPg->pDirtyPrev
+ );
+ pCache->pSynced = pPg;
+ if( !pPg ){
+ for(pPg=pCache->pDirtyTail; pPg && pPg->nRef; pPg=pPg->pDirtyPrev);
+ }
+ if( pPg ){
+ int rc;
+#ifdef SQLITE_LOG_CACHE_SPILL
+ sqlite3_log(SQLITE_FULL,
+ "spill page %d making room for %d - cache used: %d/%d",
+ pPg->pgno, pgno,
+ sqlite3GlobalConfig.pcache2.xPagecount(pCache->pCache),
+ numberOfCachePages(pCache));
+#endif
+ pcacheTrace(("%p.SPILL %d\n",pCache,pPg->pgno));
+ rc = pCache->xStress(pCache->pStress, pPg);
+ pcacheDump(pCache);
+ if( rc!=SQLITE_OK && rc!=SQLITE_BUSY ){
+ return rc;
+ }
+ }
+ }
+ *ppPage = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, 2);
+ return *ppPage==0 ? SQLITE_NOMEM_BKPT : SQLITE_OK;
+}
+
+/*
+** This is a helper routine for sqlite3PcacheFetchFinish()
+**
+** In the uncommon case where the page being fetched has not been
+** initialized, this routine is invoked to do the initialization.
+** This routine is broken out into a separate function since it
+** requires extra stack manipulation that can be avoided in the common
+** case.
+*/
+static SQLITE_NOINLINE PgHdr *pcacheFetchFinishWithInit(
+ PCache *pCache, /* Obtain the page from this cache */
+ Pgno pgno, /* Page number obtained */
+ sqlite3_pcache_page *pPage /* Page obtained by prior PcacheFetch() call */
+){
+ PgHdr *pPgHdr;
+ assert( pPage!=0 );
+ pPgHdr = (PgHdr*)pPage->pExtra;
+ assert( pPgHdr->pPage==0 );
+ memset(&pPgHdr->pDirty, 0, sizeof(PgHdr) - offsetof(PgHdr,pDirty));
+ pPgHdr->pPage = pPage;
+ pPgHdr->pData = pPage->pBuf;
+ pPgHdr->pExtra = (void *)&pPgHdr[1];
+ memset(pPgHdr->pExtra, 0, 8);
+ pPgHdr->pCache = pCache;
+ pPgHdr->pgno = pgno;
+ pPgHdr->flags = PGHDR_CLEAN;
+ return sqlite3PcacheFetchFinish(pCache,pgno,pPage);
+}
+
+/*
+** This routine converts the sqlite3_pcache_page object returned by
+** sqlite3PcacheFetch() into an initialized PgHdr object. This routine
+** must be called after sqlite3PcacheFetch() in order to get a usable
+** result.
+*/
+SQLITE_PRIVATE PgHdr *sqlite3PcacheFetchFinish(
+ PCache *pCache, /* Obtain the page from this cache */
+ Pgno pgno, /* Page number obtained */
+ sqlite3_pcache_page *pPage /* Page obtained by prior PcacheFetch() call */
+){
+ PgHdr *pPgHdr;
+
+ assert( pPage!=0 );
+ pPgHdr = (PgHdr *)pPage->pExtra;
+
+ if( !pPgHdr->pPage ){
+ return pcacheFetchFinishWithInit(pCache, pgno, pPage);
+ }
+ pCache->nRefSum++;
+ pPgHdr->nRef++;
+ assert( sqlite3PcachePageSanity(pPgHdr) );
+ return pPgHdr;
+}
+
+/*
+** Decrement the reference count on a page. If the page is clean and the
+** reference count drops to 0, then it is made eligible for recycling.
+*/
+SQLITE_PRIVATE void SQLITE_NOINLINE sqlite3PcacheRelease(PgHdr *p){
+ assert( p->nRef>0 );
+ p->pCache->nRefSum--;
+ if( (--p->nRef)==0 ){
+ if( p->flags&PGHDR_CLEAN ){
+ pcacheUnpin(p);
+ }else{
+ pcacheManageDirtyList(p, PCACHE_DIRTYLIST_FRONT);
+ }
+ }
+}
+
+/*
+** Increase the reference count of a supplied page by 1.
+*/
+SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr *p){
+ assert(p->nRef>0);
+ assert( sqlite3PcachePageSanity(p) );
+ p->nRef++;
+ p->pCache->nRefSum++;
+}
+
+/*
+** Drop a page from the cache. There must be exactly one reference to the
+** page. This function deletes that reference, so after it returns the
+** page pointed to by p is invalid.
+*/
+SQLITE_PRIVATE void sqlite3PcacheDrop(PgHdr *p){
+ assert( p->nRef==1 );
+ assert( sqlite3PcachePageSanity(p) );
+ if( p->flags&PGHDR_DIRTY ){
+ pcacheManageDirtyList(p, PCACHE_DIRTYLIST_REMOVE);
+ }
+ p->pCache->nRefSum--;
+ sqlite3GlobalConfig.pcache2.xUnpin(p->pCache->pCache, p->pPage, 1);
+}
+
+/*
+** Make sure the page is marked as dirty. If it isn't dirty already,
+** make it so.
+*/
+SQLITE_PRIVATE void sqlite3PcacheMakeDirty(PgHdr *p){
+ assert( p->nRef>0 );
+ assert( sqlite3PcachePageSanity(p) );
+ if( p->flags & (PGHDR_CLEAN|PGHDR_DONT_WRITE) ){ /*OPTIMIZATION-IF-FALSE*/
+ p->flags &= ~PGHDR_DONT_WRITE;
+ if( p->flags & PGHDR_CLEAN ){
+ p->flags ^= (PGHDR_DIRTY|PGHDR_CLEAN);
+ pcacheTrace(("%p.DIRTY %d\n",p->pCache,p->pgno));
+ assert( (p->flags & (PGHDR_DIRTY|PGHDR_CLEAN))==PGHDR_DIRTY );
+ pcacheManageDirtyList(p, PCACHE_DIRTYLIST_ADD);
+ }
+ assert( sqlite3PcachePageSanity(p) );
+ }
+}
+
+/*
+** Make sure the page is marked as clean. If it isn't clean already,
+** make it so.
+*/
+SQLITE_PRIVATE void sqlite3PcacheMakeClean(PgHdr *p){
+ assert( sqlite3PcachePageSanity(p) );
+ assert( (p->flags & PGHDR_DIRTY)!=0 );
+ assert( (p->flags & PGHDR_CLEAN)==0 );
+ pcacheManageDirtyList(p, PCACHE_DIRTYLIST_REMOVE);
+ p->flags &= ~(PGHDR_DIRTY|PGHDR_NEED_SYNC|PGHDR_WRITEABLE);
+ p->flags |= PGHDR_CLEAN;
+ pcacheTrace(("%p.CLEAN %d\n",p->pCache,p->pgno));
+ assert( sqlite3PcachePageSanity(p) );
+ if( p->nRef==0 ){
+ pcacheUnpin(p);
+ }
+}
+
+/*
+** Make every page in the cache clean.
+*/
+SQLITE_PRIVATE void sqlite3PcacheCleanAll(PCache *pCache){
+ PgHdr *p;
+ pcacheTrace(("%p.CLEAN-ALL\n",pCache));
+ while( (p = pCache->pDirty)!=0 ){
+ sqlite3PcacheMakeClean(p);
+ }
+}
+
+/*
+** Clear the PGHDR_NEED_SYNC and PGHDR_WRITEABLE flag from all dirty pages.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClearWritable(PCache *pCache){
+ PgHdr *p;
+ pcacheTrace(("%p.CLEAR-WRITEABLE\n",pCache));
+ for(p=pCache->pDirty; p; p=p->pDirtyNext){
+ p->flags &= ~(PGHDR_NEED_SYNC|PGHDR_WRITEABLE);
+ }
+ pCache->pSynced = pCache->pDirtyTail;
+}
+
+/*
+** Clear the PGHDR_NEED_SYNC flag from all dirty pages.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClearSyncFlags(PCache *pCache){
+ PgHdr *p;
+ for(p=pCache->pDirty; p; p=p->pDirtyNext){
+ p->flags &= ~PGHDR_NEED_SYNC;
+ }
+ pCache->pSynced = pCache->pDirtyTail;
+}
+
+/*
+** Change the page number of page p to newPgno.
+*/
+SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
+ PCache *pCache = p->pCache;
+ assert( p->nRef>0 );
+ assert( newPgno>0 );
+ assert( sqlite3PcachePageSanity(p) );
+ pcacheTrace(("%p.MOVE %d -> %d\n",pCache,p->pgno,newPgno));
+ sqlite3GlobalConfig.pcache2.xRekey(pCache->pCache, p->pPage, p->pgno,newPgno);
+ p->pgno = newPgno;
+ if( (p->flags&PGHDR_DIRTY) && (p->flags&PGHDR_NEED_SYNC) ){
+ pcacheManageDirtyList(p, PCACHE_DIRTYLIST_FRONT);
+ }
+}
+
+/*
+** Drop every cache entry whose page number is greater than "pgno". The
+** caller must ensure that there are no outstanding references to any pages
+** other than page 1 with a page number greater than pgno.
+**
+** If there is a reference to page 1 and the pgno parameter passed to this
+** function is 0, then the data area associated with page 1 is zeroed, but
+** the page object is not dropped.
+*/
+SQLITE_PRIVATE void sqlite3PcacheTruncate(PCache *pCache, Pgno pgno){
+ if( pCache->pCache ){
+ PgHdr *p;
+ PgHdr *pNext;
+ pcacheTrace(("%p.TRUNCATE %d\n",pCache,pgno));
+ for(p=pCache->pDirty; p; p=pNext){
+ pNext = p->pDirtyNext;
+ /* This routine never gets call with a positive pgno except right
+ ** after sqlite3PcacheCleanAll(). So if there are dirty pages,
+ ** it must be that pgno==0.
+ */
+ assert( p->pgno>0 );
+ if( p->pgno>pgno ){
+ assert( p->flags&PGHDR_DIRTY );
+ sqlite3PcacheMakeClean(p);
+ }
+ }
+ if( pgno==0 && pCache->nRefSum ){
+ sqlite3_pcache_page *pPage1;
+ pPage1 = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache,1,0);
+ if( ALWAYS(pPage1) ){ /* Page 1 is always available in cache, because
+ ** pCache->nRefSum>0 */
+ memset(pPage1->pBuf, 0, pCache->szPage);
+ pgno = 1;
+ }
+ }
+ sqlite3GlobalConfig.pcache2.xTruncate(pCache->pCache, pgno+1);
+ }
+}
+
+/*
+** Close a cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClose(PCache *pCache){
+ assert( pCache->pCache!=0 );
+ pcacheTrace(("%p.CLOSE\n",pCache));
+ sqlite3GlobalConfig.pcache2.xDestroy(pCache->pCache);
+}
+
+/*
+** Discard the contents of the cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClear(PCache *pCache){
+ sqlite3PcacheTruncate(pCache, 0);
+}
+
+/*
+** Merge two lists of pages connected by pDirty and in pgno order.
+** Do not bother fixing the pDirtyPrev pointers.
+*/
+static PgHdr *pcacheMergeDirtyList(PgHdr *pA, PgHdr *pB){
+ PgHdr result, *pTail;
+ pTail = &result;
+ assert( pA!=0 && pB!=0 );
+ for(;;){
+ if( pA->pgnopgno ){
+ pTail->pDirty = pA;
+ pTail = pA;
+ pA = pA->pDirty;
+ if( pA==0 ){
+ pTail->pDirty = pB;
+ break;
+ }
+ }else{
+ pTail->pDirty = pB;
+ pTail = pB;
+ pB = pB->pDirty;
+ if( pB==0 ){
+ pTail->pDirty = pA;
+ break;
+ }
+ }
+ }
+ return result.pDirty;
+}
+
+/*
+** Sort the list of pages in accending order by pgno. Pages are
+** connected by pDirty pointers. The pDirtyPrev pointers are
+** corrupted by this sort.
+**
+** Since there cannot be more than 2^31 distinct pages in a database,
+** there cannot be more than 31 buckets required by the merge sorter.
+** One extra bucket is added to catch overflow in case something
+** ever changes to make the previous sentence incorrect.
+*/
+#define N_SORT_BUCKET 32
+static PgHdr *pcacheSortDirtyList(PgHdr *pIn){
+ PgHdr *a[N_SORT_BUCKET], *p;
+ int i;
+ memset(a, 0, sizeof(a));
+ while( pIn ){
+ p = pIn;
+ pIn = p->pDirty;
+ p->pDirty = 0;
+ for(i=0; ALWAYS(ipDirty; p; p=p->pDirtyNext){
+ p->pDirty = p->pDirtyNext;
+ }
+ return pcacheSortDirtyList(pCache->pDirty);
+}
+
+/*
+** Return the total number of references to all pages held by the cache.
+**
+** This is not the total number of pages referenced, but the sum of the
+** reference count for all pages.
+*/
+SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache *pCache){
+ return pCache->nRefSum;
+}
+
+/*
+** Return the number of references to the page supplied as an argument.
+*/
+SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr *p){
+ return p->nRef;
+}
+
+/*
+** Return the total number of pages in the cache.
+*/
+SQLITE_PRIVATE int sqlite3PcachePagecount(PCache *pCache){
+ assert( pCache->pCache!=0 );
+ return sqlite3GlobalConfig.pcache2.xPagecount(pCache->pCache);
+}
+
+#ifdef SQLITE_TEST
+/*
+** Get the suggested cache-size value.
+*/
+SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *pCache){
+ return numberOfCachePages(pCache);
+}
+#endif
+
+/*
+** Set the suggested cache-size value.
+*/
+SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *pCache, int mxPage){
+ assert( pCache->pCache!=0 );
+ pCache->szCache = mxPage;
+ sqlite3GlobalConfig.pcache2.xCachesize(pCache->pCache,
+ numberOfCachePages(pCache));
+}
+
+/*
+** Set the suggested cache-spill value. Make no changes if if the
+** argument is zero. Return the effective cache-spill size, which will
+** be the larger of the szSpill and szCache.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSetSpillsize(PCache *p, int mxPage){
+ int res;
+ assert( p->pCache!=0 );
+ if( mxPage ){
+ if( mxPage<0 ){
+ mxPage = (int)((-1024*(i64)mxPage)/(p->szPage+p->szExtra));
+ }
+ p->szSpill = mxPage;
+ }
+ res = numberOfCachePages(p);
+ if( resszSpill ) res = p->szSpill;
+ return res;
+}
+
+/*
+** Free up as much memory as possible from the page cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheShrink(PCache *pCache){
+ assert( pCache->pCache!=0 );
+ sqlite3GlobalConfig.pcache2.xShrink(pCache->pCache);
+}
+
+/*
+** Return the size of the header added by this middleware layer
+** in the page-cache hierarchy.
+*/
+SQLITE_PRIVATE int sqlite3HeaderSizePcache(void){ return ROUND8(sizeof(PgHdr)); }
+
+/*
+** Return the number of dirty pages currently in the cache, as a percentage
+** of the configured cache size.
+*/
+SQLITE_PRIVATE int sqlite3PCachePercentDirty(PCache *pCache){
+ PgHdr *pDirty;
+ int nDirty = 0;
+ int nCache = numberOfCachePages(pCache);
+ for(pDirty=pCache->pDirty; pDirty; pDirty=pDirty->pDirtyNext) nDirty++;
+ return nCache ? (int)(((i64)nDirty * 100) / nCache) : 0;
+}
+
+#if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
+/*
+** For all dirty pages currently in the cache, invoke the specified
+** callback. This is only used if the SQLITE_CHECK_PAGES macro is
+** defined.
+*/
+SQLITE_PRIVATE void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *)){
+ PgHdr *pDirty;
+ for(pDirty=pCache->pDirty; pDirty; pDirty=pDirty->pDirtyNext){
+ xIter(pDirty);
+ }
+}
+#endif
+
+/************** End of pcache.c **********************************************/
+/************** Begin file pcache1.c *****************************************/
+/*
+** 2008 November 05
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file implements the default page cache implementation (the
+** sqlite3_pcache interface). It also contains part of the implementation
+** of the SQLITE_CONFIG_PAGECACHE and sqlite3_release_memory() features.
+** If the default page cache implementation is overridden, then neither of
+** these two features are available.
+**
+** A Page cache line looks like this:
+**
+** -------------------------------------------------------------
+** | database page content | PgHdr1 | MemPage | PgHdr |
+** -------------------------------------------------------------
+**
+** The database page content is up front (so that buffer overreads tend to
+** flow harmlessly into the PgHdr1, MemPage, and PgHdr extensions). MemPage
+** is the extension added by the btree.c module containing information such
+** as the database page number and how that database page is used. PgHdr
+** is added by the pcache.c layer and contains information used to keep track
+** of which pages are "dirty". PgHdr1 is an extension added by this
+** module (pcache1.c). The PgHdr1 header is a subclass of sqlite3_pcache_page.
+** PgHdr1 contains information needed to look up a page by its page number.
+** The superclass sqlite3_pcache_page.pBuf points to the start of the
+** database page content and sqlite3_pcache_page.pExtra points to PgHdr.
+**
+** The size of the extension (MemPage+PgHdr+PgHdr1) can be determined at
+** runtime using sqlite3_config(SQLITE_CONFIG_PCACHE_HDRSZ, &size). The
+** sizes of the extensions sum to 272 bytes on x64 for 3.8.10, but this
+** size can vary according to architecture, compile-time options, and
+** SQLite library version number.
+**
+** If SQLITE_PCACHE_SEPARATE_HEADER is defined, then the extension is obtained
+** using a separate memory allocation from the database page content. This
+** seeks to overcome the "clownshoe" problem (also called "internal
+** fragmentation" in academic literature) of allocating a few bytes more
+** than a power of two with the memory allocator rounding up to the next
+** power of two, and leaving the rounded-up space unused.
+**
+** This module tracks pointers to PgHdr1 objects. Only pcache.c communicates
+** with this module. Information is passed back and forth as PgHdr1 pointers.
+**
+** The pcache.c and pager.c modules deal pointers to PgHdr objects.
+** The btree.c module deals with pointers to MemPage objects.
+**
+** SOURCE OF PAGE CACHE MEMORY:
+**
+** Memory for a page might come from any of three sources:
+**
+** (1) The general-purpose memory allocator - sqlite3Malloc()
+** (2) Global page-cache memory provided using sqlite3_config() with
+** SQLITE_CONFIG_PAGECACHE.
+** (3) PCache-local bulk allocation.
+**
+** The third case is a chunk of heap memory (defaulting to 100 pages worth)
+** that is allocated when the page cache is created. The size of the local
+** bulk allocation can be adjusted using
+**
+** sqlite3_config(SQLITE_CONFIG_PAGECACHE, (void*)0, 0, N).
+**
+** If N is positive, then N pages worth of memory are allocated using a single
+** sqlite3Malloc() call and that memory is used for the first N pages allocated.
+** Or if N is negative, then -1024*N bytes of memory are allocated and used
+** for as many pages as can be accomodated.
+**
+** Only one of (2) or (3) can be used. Once the memory available to (2) or
+** (3) is exhausted, subsequent allocations fail over to the general-purpose
+** memory allocator (1).
+**
+** Earlier versions of SQLite used only methods (1) and (2). But experiments
+** show that method (3) with N==100 provides about a 5% performance boost for
+** common workloads.
+*/
+/* #include "sqliteInt.h" */
+
+typedef struct PCache1 PCache1;
+typedef struct PgHdr1 PgHdr1;
+typedef struct PgFreeslot PgFreeslot;
+typedef struct PGroup PGroup;
+
+/*
+** Each cache entry is represented by an instance of the following
+** structure. Unless SQLITE_PCACHE_SEPARATE_HEADER is defined, a buffer of
+** PgHdr1.pCache->szPage bytes is allocated directly before this structure
+** in memory.
+*/
+struct PgHdr1 {
+ sqlite3_pcache_page page; /* Base class. Must be first. pBuf & pExtra */
+ unsigned int iKey; /* Key value (page number) */
+ u8 isBulkLocal; /* This page from bulk local storage */
+ u8 isAnchor; /* This is the PGroup.lru element */
+ PgHdr1 *pNext; /* Next in hash table chain */
+ PCache1 *pCache; /* Cache that currently owns this page */
+ PgHdr1 *pLruNext; /* Next in LRU list of unpinned pages */
+ PgHdr1 *pLruPrev; /* Previous in LRU list of unpinned pages */
+};
+
+/*
+** A page is pinned if it is no on the LRU list
+*/
+#define PAGE_IS_PINNED(p) ((p)->pLruNext==0)
+#define PAGE_IS_UNPINNED(p) ((p)->pLruNext!=0)
+
+/* Each page cache (or PCache) belongs to a PGroup. A PGroup is a set
+** of one or more PCaches that are able to recycle each other's unpinned
+** pages when they are under memory pressure. A PGroup is an instance of
+** the following object.
+**
+** This page cache implementation works in one of two modes:
+**
+** (1) Every PCache is the sole member of its own PGroup. There is
+** one PGroup per PCache.
+**
+** (2) There is a single global PGroup that all PCaches are a member
+** of.
+**
+** Mode 1 uses more memory (since PCache instances are not able to rob
+** unused pages from other PCaches) but it also operates without a mutex,
+** and is therefore often faster. Mode 2 requires a mutex in order to be
+** threadsafe, but recycles pages more efficiently.
+**
+** For mode (1), PGroup.mutex is NULL. For mode (2) there is only a single
+** PGroup which is the pcache1.grp global variable and its mutex is
+** SQLITE_MUTEX_STATIC_LRU.
+*/
+struct PGroup {
+ sqlite3_mutex *mutex; /* MUTEX_STATIC_LRU or NULL */
+ unsigned int nMaxPage; /* Sum of nMax for purgeable caches */
+ unsigned int nMinPage; /* Sum of nMin for purgeable caches */
+ unsigned int mxPinned; /* nMaxpage + 10 - nMinPage */
+ unsigned int nPurgeable; /* Number of purgeable pages allocated */
+ PgHdr1 lru; /* The beginning and end of the LRU list */
+};
+
+/* Each page cache is an instance of the following object. Every
+** open database file (including each in-memory database and each
+** temporary or transient database) has a single page cache which
+** is an instance of this object.
+**
+** Pointers to structures of this type are cast and returned as
+** opaque sqlite3_pcache* handles.
+*/
+struct PCache1 {
+ /* Cache configuration parameters. Page size (szPage) and the purgeable
+ ** flag (bPurgeable) and the pnPurgeable pointer are all set when the
+ ** cache is created and are never changed thereafter. nMax may be
+ ** modified at any time by a call to the pcache1Cachesize() method.
+ ** The PGroup mutex must be held when accessing nMax.
+ */
+ PGroup *pGroup; /* PGroup this cache belongs to */
+ unsigned int *pnPurgeable; /* Pointer to pGroup->nPurgeable */
+ int szPage; /* Size of database content section */
+ int szExtra; /* sizeof(MemPage)+sizeof(PgHdr) */
+ int szAlloc; /* Total size of one pcache line */
+ int bPurgeable; /* True if cache is purgeable */
+ unsigned int nMin; /* Minimum number of pages reserved */
+ unsigned int nMax; /* Configured "cache_size" value */
+ unsigned int n90pct; /* nMax*9/10 */
+ unsigned int iMaxKey; /* Largest key seen since xTruncate() */
+
+ /* Hash table of all pages. The following variables may only be accessed
+ ** when the accessor is holding the PGroup mutex.
+ */
+ unsigned int nRecyclable; /* Number of pages in the LRU list */
+ unsigned int nPage; /* Total number of pages in apHash */
+ unsigned int nHash; /* Number of slots in apHash[] */
+ PgHdr1 **apHash; /* Hash table for fast lookup by key */
+ PgHdr1 *pFree; /* List of unused pcache-local pages */
+ void *pBulk; /* Bulk memory used by pcache-local */
+};
+
+/*
+** Free slots in the allocator used to divide up the global page cache
+** buffer provided using the SQLITE_CONFIG_PAGECACHE mechanism.
+*/
+struct PgFreeslot {
+ PgFreeslot *pNext; /* Next free slot */
+};
+
+/*
+** Global data used by this cache.
+*/
+static SQLITE_WSD struct PCacheGlobal {
+ PGroup grp; /* The global PGroup for mode (2) */
+
+ /* Variables related to SQLITE_CONFIG_PAGECACHE settings. The
+ ** szSlot, nSlot, pStart, pEnd, nReserve, and isInit values are all
+ ** fixed at sqlite3_initialize() time and do not require mutex protection.
+ ** The nFreeSlot and pFree values do require mutex protection.
+ */
+ int isInit; /* True if initialized */
+ int separateCache; /* Use a new PGroup for each PCache */
+ int nInitPage; /* Initial bulk allocation size */
+ int szSlot; /* Size of each free slot */
+ int nSlot; /* The number of pcache slots */
+ int nReserve; /* Try to keep nFreeSlot above this */
+ void *pStart, *pEnd; /* Bounds of global page cache memory */
+ /* Above requires no mutex. Use mutex below for variable that follow. */
+ sqlite3_mutex *mutex; /* Mutex for accessing the following: */
+ PgFreeslot *pFree; /* Free page blocks */
+ int nFreeSlot; /* Number of unused pcache slots */
+ /* The following value requires a mutex to change. We skip the mutex on
+ ** reading because (1) most platforms read a 32-bit integer atomically and
+ ** (2) even if an incorrect value is read, no great harm is done since this
+ ** is really just an optimization. */
+ int bUnderPressure; /* True if low on PAGECACHE memory */
+} pcache1_g;
+
+/*
+** All code in this file should access the global structure above via the
+** alias "pcache1". This ensures that the WSD emulation is used when
+** compiling for systems that do not support real WSD.
+*/
+#define pcache1 (GLOBAL(struct PCacheGlobal, pcache1_g))
+
+/*
+** Macros to enter and leave the PCache LRU mutex.
+*/
+#if !defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
+# define pcache1EnterMutex(X) assert((X)->mutex==0)
+# define pcache1LeaveMutex(X) assert((X)->mutex==0)
+# define PCACHE1_MIGHT_USE_GROUP_MUTEX 0
+#else
+# define pcache1EnterMutex(X) sqlite3_mutex_enter((X)->mutex)
+# define pcache1LeaveMutex(X) sqlite3_mutex_leave((X)->mutex)
+# define PCACHE1_MIGHT_USE_GROUP_MUTEX 1
+#endif
+
+/******************************************************************************/
+/******** Page Allocation/SQLITE_CONFIG_PCACHE Related Functions **************/
+
+
+/*
+** This function is called during initialization if a static buffer is
+** supplied to use for the page-cache by passing the SQLITE_CONFIG_PAGECACHE
+** verb to sqlite3_config(). Parameter pBuf points to an allocation large
+** enough to contain 'n' buffers of 'sz' bytes each.
+**
+** This routine is called from sqlite3_initialize() and so it is guaranteed
+** to be serialized already. There is no need for further mutexing.
+*/
+SQLITE_PRIVATE void sqlite3PCacheBufferSetup(void *pBuf, int sz, int n){
+ if( pcache1.isInit ){
+ PgFreeslot *p;
+ if( pBuf==0 ) sz = n = 0;
+ if( n==0 ) sz = 0;
+ sz = ROUNDDOWN8(sz);
+ pcache1.szSlot = sz;
+ pcache1.nSlot = pcache1.nFreeSlot = n;
+ pcache1.nReserve = n>90 ? 10 : (n/10 + 1);
+ pcache1.pStart = pBuf;
+ pcache1.pFree = 0;
+ pcache1.bUnderPressure = 0;
+ while( n-- ){
+ p = (PgFreeslot*)pBuf;
+ p->pNext = pcache1.pFree;
+ pcache1.pFree = p;
+ pBuf = (void*)&((char*)pBuf)[sz];
+ }
+ pcache1.pEnd = pBuf;
+ }
+}
+
+/*
+** Try to initialize the pCache->pFree and pCache->pBulk fields. Return
+** true if pCache->pFree ends up containing one or more free pages.
+*/
+static int pcache1InitBulk(PCache1 *pCache){
+ i64 szBulk;
+ char *zBulk;
+ if( pcache1.nInitPage==0 ) return 0;
+ /* Do not bother with a bulk allocation if the cache size very small */
+ if( pCache->nMax<3 ) return 0;
+ sqlite3BeginBenignMalloc();
+ if( pcache1.nInitPage>0 ){
+ szBulk = pCache->szAlloc * (i64)pcache1.nInitPage;
+ }else{
+ szBulk = -1024 * (i64)pcache1.nInitPage;
+ }
+ if( szBulk > pCache->szAlloc*(i64)pCache->nMax ){
+ szBulk = pCache->szAlloc*(i64)pCache->nMax;
+ }
+ zBulk = pCache->pBulk = sqlite3Malloc( szBulk );
+ sqlite3EndBenignMalloc();
+ if( zBulk ){
+ int nBulk = sqlite3MallocSize(zBulk)/pCache->szAlloc;
+ do{
+ PgHdr1 *pX = (PgHdr1*)&zBulk[pCache->szPage];
+ pX->page.pBuf = zBulk;
+ pX->page.pExtra = &pX[1];
+ pX->isBulkLocal = 1;
+ pX->isAnchor = 0;
+ pX->pNext = pCache->pFree;
+ pCache->pFree = pX;
+ zBulk += pCache->szAlloc;
+ }while( --nBulk );
+ }
+ return pCache->pFree!=0;
+}
+
+/*
+** Malloc function used within this file to allocate space from the buffer
+** configured using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no
+** such buffer exists or there is no space left in it, this function falls
+** back to sqlite3Malloc().
+**
+** Multiple threads can run this routine at the same time. Global variables
+** in pcache1 need to be protected via mutex.
+*/
+static void *pcache1Alloc(int nByte){
+ void *p = 0;
+ assert( sqlite3_mutex_notheld(pcache1.grp.mutex) );
+ if( nByte<=pcache1.szSlot ){
+ sqlite3_mutex_enter(pcache1.mutex);
+ p = (PgHdr1 *)pcache1.pFree;
+ if( p ){
+ pcache1.pFree = pcache1.pFree->pNext;
+ pcache1.nFreeSlot--;
+ pcache1.bUnderPressure = pcache1.nFreeSlot=0 );
+ sqlite3StatusHighwater(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
+ sqlite3StatusUp(SQLITE_STATUS_PAGECACHE_USED, 1);
+ }
+ sqlite3_mutex_leave(pcache1.mutex);
+ }
+ if( p==0 ){
+ /* Memory is not available in the SQLITE_CONFIG_PAGECACHE pool. Get
+ ** it from sqlite3Malloc instead.
+ */
+ p = sqlite3Malloc(nByte);
+#ifndef SQLITE_DISABLE_PAGECACHE_OVERFLOW_STATS
+ if( p ){
+ int sz = sqlite3MallocSize(p);
+ sqlite3_mutex_enter(pcache1.mutex);
+ sqlite3StatusHighwater(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
+ sqlite3StatusUp(SQLITE_STATUS_PAGECACHE_OVERFLOW, sz);
+ sqlite3_mutex_leave(pcache1.mutex);
+ }
+#endif
+ sqlite3MemdebugSetType(p, MEMTYPE_PCACHE);
+ }
+ return p;
+}
+
+/*
+** Free an allocated buffer obtained from pcache1Alloc().
+*/
+static void pcache1Free(void *p){
+ if( p==0 ) return;
+ if( SQLITE_WITHIN(p, pcache1.pStart, pcache1.pEnd) ){
+ PgFreeslot *pSlot;
+ sqlite3_mutex_enter(pcache1.mutex);
+ sqlite3StatusDown(SQLITE_STATUS_PAGECACHE_USED, 1);
+ pSlot = (PgFreeslot*)p;
+ pSlot->pNext = pcache1.pFree;
+ pcache1.pFree = pSlot;
+ pcache1.nFreeSlot++;
+ pcache1.bUnderPressure = pcache1.nFreeSlot=pcache1.pStart && ppGroup->mutex) );
+ if( pCache->pFree || (pCache->nPage==0 && pcache1InitBulk(pCache)) ){
+ p = pCache->pFree;
+ pCache->pFree = p->pNext;
+ p->pNext = 0;
+ }else{
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+ /* The group mutex must be released before pcache1Alloc() is called. This
+ ** is because it might call sqlite3_release_memory(), which assumes that
+ ** this mutex is not held. */
+ assert( pcache1.separateCache==0 );
+ assert( pCache->pGroup==&pcache1.grp );
+ pcache1LeaveMutex(pCache->pGroup);
+#endif
+ if( benignMalloc ){ sqlite3BeginBenignMalloc(); }
+#ifdef SQLITE_PCACHE_SEPARATE_HEADER
+ pPg = pcache1Alloc(pCache->szPage);
+ p = sqlite3Malloc(sizeof(PgHdr1) + pCache->szExtra);
+ if( !pPg || !p ){
+ pcache1Free(pPg);
+ sqlite3_free(p);
+ pPg = 0;
+ }
+#else
+ pPg = pcache1Alloc(pCache->szAlloc);
+ p = (PgHdr1 *)&((u8 *)pPg)[pCache->szPage];
+#endif
+ if( benignMalloc ){ sqlite3EndBenignMalloc(); }
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+ pcache1EnterMutex(pCache->pGroup);
+#endif
+ if( pPg==0 ) return 0;
+ p->page.pBuf = pPg;
+ p->page.pExtra = &p[1];
+ p->isBulkLocal = 0;
+ p->isAnchor = 0;
+ }
+ (*pCache->pnPurgeable)++;
+ return p;
+}
+
+/*
+** Free a page object allocated by pcache1AllocPage().
+*/
+static void pcache1FreePage(PgHdr1 *p){
+ PCache1 *pCache;
+ assert( p!=0 );
+ pCache = p->pCache;
+ assert( sqlite3_mutex_held(p->pCache->pGroup->mutex) );
+ if( p->isBulkLocal ){
+ p->pNext = pCache->pFree;
+ pCache->pFree = p;
+ }else{
+ pcache1Free(p->page.pBuf);
+#ifdef SQLITE_PCACHE_SEPARATE_HEADER
+ sqlite3_free(p);
+#endif
+ }
+ (*pCache->pnPurgeable)--;
+}
+
+/*
+** Malloc function used by SQLite to obtain space from the buffer configured
+** using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no such buffer
+** exists, this function falls back to sqlite3Malloc().
+*/
+SQLITE_PRIVATE void *sqlite3PageMalloc(int sz){
+ return pcache1Alloc(sz);
+}
+
+/*
+** Free an allocated buffer obtained from sqlite3PageMalloc().
+*/
+SQLITE_PRIVATE void sqlite3PageFree(void *p){
+ pcache1Free(p);
+}
+
+
+/*
+** Return true if it desirable to avoid allocating a new page cache
+** entry.
+**
+** If memory was allocated specifically to the page cache using
+** SQLITE_CONFIG_PAGECACHE but that memory has all been used, then
+** it is desirable to avoid allocating a new page cache entry because
+** presumably SQLITE_CONFIG_PAGECACHE was suppose to be sufficient
+** for all page cache needs and we should not need to spill the
+** allocation onto the heap.
+**
+** Or, the heap is used for all page cache memory but the heap is
+** under memory pressure, then again it is desirable to avoid
+** allocating a new page cache entry in order to avoid stressing
+** the heap even further.
+*/
+static int pcache1UnderMemoryPressure(PCache1 *pCache){
+ if( pcache1.nSlot && (pCache->szPage+pCache->szExtra)<=pcache1.szSlot ){
+ return pcache1.bUnderPressure;
+ }else{
+ return sqlite3HeapNearlyFull();
+ }
+}
+
+/******************************************************************************/
+/******** General Implementation Functions ************************************/
+
+/*
+** This function is used to resize the hash table used by the cache passed
+** as the first argument.
+**
+** The PCache mutex must be held when this function is called.
+*/
+static void pcache1ResizeHash(PCache1 *p){
+ PgHdr1 **apNew;
+ unsigned int nNew;
+ unsigned int i;
+
+ assert( sqlite3_mutex_held(p->pGroup->mutex) );
+
+ nNew = p->nHash*2;
+ if( nNew<256 ){
+ nNew = 256;
+ }
+
+ pcache1LeaveMutex(p->pGroup);
+ if( p->nHash ){ sqlite3BeginBenignMalloc(); }
+ apNew = (PgHdr1 **)sqlite3MallocZero(sizeof(PgHdr1 *)*nNew);
+ if( p->nHash ){ sqlite3EndBenignMalloc(); }
+ pcache1EnterMutex(p->pGroup);
+ if( apNew ){
+ for(i=0; inHash; i++){
+ PgHdr1 *pPage;
+ PgHdr1 *pNext = p->apHash[i];
+ while( (pPage = pNext)!=0 ){
+ unsigned int h = pPage->iKey % nNew;
+ pNext = pPage->pNext;
+ pPage->pNext = apNew[h];
+ apNew[h] = pPage;
+ }
+ }
+ sqlite3_free(p->apHash);
+ p->apHash = apNew;
+ p->nHash = nNew;
+ }
+}
+
+/*
+** This function is used internally to remove the page pPage from the
+** PGroup LRU list, if is part of it. If pPage is not part of the PGroup
+** LRU list, then this function is a no-op.
+**
+** The PGroup mutex must be held when this function is called.
+*/
+static PgHdr1 *pcache1PinPage(PgHdr1 *pPage){
+ assert( pPage!=0 );
+ assert( PAGE_IS_UNPINNED(pPage) );
+ assert( pPage->pLruNext );
+ assert( pPage->pLruPrev );
+ assert( sqlite3_mutex_held(pPage->pCache->pGroup->mutex) );
+ pPage->pLruPrev->pLruNext = pPage->pLruNext;
+ pPage->pLruNext->pLruPrev = pPage->pLruPrev;
+ pPage->pLruNext = 0;
+ pPage->pLruPrev = 0;
+ assert( pPage->isAnchor==0 );
+ assert( pPage->pCache->pGroup->lru.isAnchor==1 );
+ pPage->pCache->nRecyclable--;
+ return pPage;
+}
+
+
+/*
+** Remove the page supplied as an argument from the hash table
+** (PCache1.apHash structure) that it is currently stored in.
+** Also free the page if freePage is true.
+**
+** The PGroup mutex must be held when this function is called.
+*/
+static void pcache1RemoveFromHash(PgHdr1 *pPage, int freeFlag){
+ unsigned int h;
+ PCache1 *pCache = pPage->pCache;
+ PgHdr1 **pp;
+
+ assert( sqlite3_mutex_held(pCache->pGroup->mutex) );
+ h = pPage->iKey % pCache->nHash;
+ for(pp=&pCache->apHash[h]; (*pp)!=pPage; pp=&(*pp)->pNext);
+ *pp = (*pp)->pNext;
+
+ pCache->nPage--;
+ if( freeFlag ) pcache1FreePage(pPage);
+}
+
+/*
+** If there are currently more than nMaxPage pages allocated, try
+** to recycle pages to reduce the number allocated to nMaxPage.
+*/
+static void pcache1EnforceMaxPage(PCache1 *pCache){
+ PGroup *pGroup = pCache->pGroup;
+ PgHdr1 *p;
+ assert( sqlite3_mutex_held(pGroup->mutex) );
+ while( pGroup->nPurgeable>pGroup->nMaxPage
+ && (p=pGroup->lru.pLruPrev)->isAnchor==0
+ ){
+ assert( p->pCache->pGroup==pGroup );
+ assert( PAGE_IS_UNPINNED(p) );
+ pcache1PinPage(p);
+ pcache1RemoveFromHash(p, 1);
+ }
+ if( pCache->nPage==0 && pCache->pBulk ){
+ sqlite3_free(pCache->pBulk);
+ pCache->pBulk = pCache->pFree = 0;
+ }
+}
+
+/*
+** Discard all pages from cache pCache with a page number (key value)
+** greater than or equal to iLimit. Any pinned pages that meet this
+** criteria are unpinned before they are discarded.
+**
+** The PCache mutex must be held when this function is called.
+*/
+static void pcache1TruncateUnsafe(
+ PCache1 *pCache, /* The cache to truncate */
+ unsigned int iLimit /* Drop pages with this pgno or larger */
+){
+ TESTONLY( int nPage = 0; ) /* To assert pCache->nPage is correct */
+ unsigned int h, iStop;
+ assert( sqlite3_mutex_held(pCache->pGroup->mutex) );
+ assert( pCache->iMaxKey >= iLimit );
+ assert( pCache->nHash > 0 );
+ if( pCache->iMaxKey - iLimit < pCache->nHash ){
+ /* If we are just shaving the last few pages off the end of the
+ ** cache, then there is no point in scanning the entire hash table.
+ ** Only scan those hash slots that might contain pages that need to
+ ** be removed. */
+ h = iLimit % pCache->nHash;
+ iStop = pCache->iMaxKey % pCache->nHash;
+ TESTONLY( nPage = -10; ) /* Disable the pCache->nPage validity check */
+ }else{
+ /* This is the general case where many pages are being removed.
+ ** It is necessary to scan the entire hash table */
+ h = pCache->nHash/2;
+ iStop = h - 1;
+ }
+ for(;;){
+ PgHdr1 **pp;
+ PgHdr1 *pPage;
+ assert( hnHash );
+ pp = &pCache->apHash[h];
+ while( (pPage = *pp)!=0 ){
+ if( pPage->iKey>=iLimit ){
+ pCache->nPage--;
+ *pp = pPage->pNext;
+ if( PAGE_IS_UNPINNED(pPage) ) pcache1PinPage(pPage);
+ pcache1FreePage(pPage);
+ }else{
+ pp = &pPage->pNext;
+ TESTONLY( if( nPage>=0 ) nPage++; )
+ }
+ }
+ if( h==iStop ) break;
+ h = (h+1) % pCache->nHash;
+ }
+ assert( nPage<0 || pCache->nPage==(unsigned)nPage );
+}
+
+/******************************************************************************/
+/******** sqlite3_pcache Methods **********************************************/
+
+/*
+** Implementation of the sqlite3_pcache.xInit method.
+*/
+static int pcache1Init(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ assert( pcache1.isInit==0 );
+ memset(&pcache1, 0, sizeof(pcache1));
+
+
+ /*
+ ** The pcache1.separateCache variable is true if each PCache has its own
+ ** private PGroup (mode-1). pcache1.separateCache is false if the single
+ ** PGroup in pcache1.grp is used for all page caches (mode-2).
+ **
+ ** * Always use a unified cache (mode-2) if ENABLE_MEMORY_MANAGEMENT
+ **
+ ** * Use a unified cache in single-threaded applications that have
+ ** configured a start-time buffer for use as page-cache memory using
+ ** sqlite3_config(SQLITE_CONFIG_PAGECACHE, pBuf, sz, N) with non-NULL
+ ** pBuf argument.
+ **
+ ** * Otherwise use separate caches (mode-1)
+ */
+#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT)
+ pcache1.separateCache = 0;
+#elif SQLITE_THREADSAFE
+ pcache1.separateCache = sqlite3GlobalConfig.pPage==0
+ || sqlite3GlobalConfig.bCoreMutex>0;
+#else
+ pcache1.separateCache = sqlite3GlobalConfig.pPage==0;
+#endif
+
+#if SQLITE_THREADSAFE
+ if( sqlite3GlobalConfig.bCoreMutex ){
+ pcache1.grp.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_LRU);
+ pcache1.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PMEM);
+ }
+#endif
+ if( pcache1.separateCache
+ && sqlite3GlobalConfig.nPage!=0
+ && sqlite3GlobalConfig.pPage==0
+ ){
+ pcache1.nInitPage = sqlite3GlobalConfig.nPage;
+ }else{
+ pcache1.nInitPage = 0;
+ }
+ pcache1.grp.mxPinned = 10;
+ pcache1.isInit = 1;
+ return SQLITE_OK;
+}
+
+/*
+** Implementation of the sqlite3_pcache.xShutdown method.
+** Note that the static mutex allocated in xInit does
+** not need to be freed.
+*/
+static void pcache1Shutdown(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ assert( pcache1.isInit!=0 );
+ memset(&pcache1, 0, sizeof(pcache1));
+}
+
+/* forward declaration */
+static void pcache1Destroy(sqlite3_pcache *p);
+
+/*
+** Implementation of the sqlite3_pcache.xCreate method.
+**
+** Allocate a new cache.
+*/
+static sqlite3_pcache *pcache1Create(int szPage, int szExtra, int bPurgeable){
+ PCache1 *pCache; /* The newly created page cache */
+ PGroup *pGroup; /* The group the new page cache will belong to */
+ int sz; /* Bytes of memory required to allocate the new cache */
+
+ assert( (szPage & (szPage-1))==0 && szPage>=512 && szPage<=65536 );
+ assert( szExtra < 300 );
+
+ sz = sizeof(PCache1) + sizeof(PGroup)*pcache1.separateCache;
+ pCache = (PCache1 *)sqlite3MallocZero(sz);
+ if( pCache ){
+ if( pcache1.separateCache ){
+ pGroup = (PGroup*)&pCache[1];
+ pGroup->mxPinned = 10;
+ }else{
+ pGroup = &pcache1.grp;
+ }
+ if( pGroup->lru.isAnchor==0 ){
+ pGroup->lru.isAnchor = 1;
+ pGroup->lru.pLruPrev = pGroup->lru.pLruNext = &pGroup->lru;
+ }
+ pCache->pGroup = pGroup;
+ pCache->szPage = szPage;
+ pCache->szExtra = szExtra;
+ pCache->szAlloc = szPage + szExtra + ROUND8(sizeof(PgHdr1));
+ pCache->bPurgeable = (bPurgeable ? 1 : 0);
+ pcache1EnterMutex(pGroup);
+ pcache1ResizeHash(pCache);
+ if( bPurgeable ){
+ pCache->nMin = 10;
+ pGroup->nMinPage += pCache->nMin;
+ pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
+ pCache->pnPurgeable = &pGroup->nPurgeable;
+ }else{
+ static unsigned int dummyCurrentPage;
+ pCache->pnPurgeable = &dummyCurrentPage;
+ }
+ pcache1LeaveMutex(pGroup);
+ if( pCache->nHash==0 ){
+ pcache1Destroy((sqlite3_pcache*)pCache);
+ pCache = 0;
+ }
+ }
+ return (sqlite3_pcache *)pCache;
+}
+
+/*
+** Implementation of the sqlite3_pcache.xCachesize method.
+**
+** Configure the cache_size limit for a cache.
+*/
+static void pcache1Cachesize(sqlite3_pcache *p, int nMax){
+ PCache1 *pCache = (PCache1 *)p;
+ if( pCache->bPurgeable ){
+ PGroup *pGroup = pCache->pGroup;
+ pcache1EnterMutex(pGroup);
+ pGroup->nMaxPage += (nMax - pCache->nMax);
+ pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
+ pCache->nMax = nMax;
+ pCache->n90pct = pCache->nMax*9/10;
+ pcache1EnforceMaxPage(pCache);
+ pcache1LeaveMutex(pGroup);
+ }
+}
+
+/*
+** Implementation of the sqlite3_pcache.xShrink method.
+**
+** Free up as much memory as possible.
+*/
+static void pcache1Shrink(sqlite3_pcache *p){
+ PCache1 *pCache = (PCache1*)p;
+ if( pCache->bPurgeable ){
+ PGroup *pGroup = pCache->pGroup;
+ int savedMaxPage;
+ pcache1EnterMutex(pGroup);
+ savedMaxPage = pGroup->nMaxPage;
+ pGroup->nMaxPage = 0;
+ pcache1EnforceMaxPage(pCache);
+ pGroup->nMaxPage = savedMaxPage;
+ pcache1LeaveMutex(pGroup);
+ }
+}
+
+/*
+** Implementation of the sqlite3_pcache.xPagecount method.
+*/
+static int pcache1Pagecount(sqlite3_pcache *p){
+ int n;
+ PCache1 *pCache = (PCache1*)p;
+ pcache1EnterMutex(pCache->pGroup);
+ n = pCache->nPage;
+ pcache1LeaveMutex(pCache->pGroup);
+ return n;
+}
+
+
+/*
+** Implement steps 3, 4, and 5 of the pcache1Fetch() algorithm described
+** in the header of the pcache1Fetch() procedure.
+**
+** This steps are broken out into a separate procedure because they are
+** usually not needed, and by avoiding the stack initialization required
+** for these steps, the main pcache1Fetch() procedure can run faster.
+*/
+static SQLITE_NOINLINE PgHdr1 *pcache1FetchStage2(
+ PCache1 *pCache,
+ unsigned int iKey,
+ int createFlag
+){
+ unsigned int nPinned;
+ PGroup *pGroup = pCache->pGroup;
+ PgHdr1 *pPage = 0;
+
+ /* Step 3: Abort if createFlag is 1 but the cache is nearly full */
+ assert( pCache->nPage >= pCache->nRecyclable );
+ nPinned = pCache->nPage - pCache->nRecyclable;
+ assert( pGroup->mxPinned == pGroup->nMaxPage + 10 - pGroup->nMinPage );
+ assert( pCache->n90pct == pCache->nMax*9/10 );
+ if( createFlag==1 && (
+ nPinned>=pGroup->mxPinned
+ || nPinned>=pCache->n90pct
+ || (pcache1UnderMemoryPressure(pCache) && pCache->nRecyclablenPage>=pCache->nHash ) pcache1ResizeHash(pCache);
+ assert( pCache->nHash>0 && pCache->apHash );
+
+ /* Step 4. Try to recycle a page. */
+ if( pCache->bPurgeable
+ && !pGroup->lru.pLruPrev->isAnchor
+ && ((pCache->nPage+1>=pCache->nMax) || pcache1UnderMemoryPressure(pCache))
+ ){
+ PCache1 *pOther;
+ pPage = pGroup->lru.pLruPrev;
+ assert( PAGE_IS_UNPINNED(pPage) );
+ pcache1RemoveFromHash(pPage, 0);
+ pcache1PinPage(pPage);
+ pOther = pPage->pCache;
+ if( pOther->szAlloc != pCache->szAlloc ){
+ pcache1FreePage(pPage);
+ pPage = 0;
+ }else{
+ pGroup->nPurgeable -= (pOther->bPurgeable - pCache->bPurgeable);
+ }
+ }
+
+ /* Step 5. If a usable page buffer has still not been found,
+ ** attempt to allocate a new one.
+ */
+ if( !pPage ){
+ pPage = pcache1AllocPage(pCache, createFlag==1);
+ }
+
+ if( pPage ){
+ unsigned int h = iKey % pCache->nHash;
+ pCache->nPage++;
+ pPage->iKey = iKey;
+ pPage->pNext = pCache->apHash[h];
+ pPage->pCache = pCache;
+ pPage->pLruPrev = 0;
+ pPage->pLruNext = 0;
+ *(void **)pPage->page.pExtra = 0;
+ pCache->apHash[h] = pPage;
+ if( iKey>pCache->iMaxKey ){
+ pCache->iMaxKey = iKey;
+ }
+ }
+ return pPage;
+}
+
+/*
+** Implementation of the sqlite3_pcache.xFetch method.
+**
+** Fetch a page by key value.
+**
+** Whether or not a new page may be allocated by this function depends on
+** the value of the createFlag argument. 0 means do not allocate a new
+** page. 1 means allocate a new page if space is easily available. 2
+** means to try really hard to allocate a new page.
+**
+** For a non-purgeable cache (a cache used as the storage for an in-memory
+** database) there is really no difference between createFlag 1 and 2. So
+** the calling function (pcache.c) will never have a createFlag of 1 on
+** a non-purgeable cache.
+**
+** There are three different approaches to obtaining space for a page,
+** depending on the value of parameter createFlag (which may be 0, 1 or 2).
+**
+** 1. Regardless of the value of createFlag, the cache is searched for a
+** copy of the requested page. If one is found, it is returned.
+**
+** 2. If createFlag==0 and the page is not already in the cache, NULL is
+** returned.
+**
+** 3. If createFlag is 1, and the page is not already in the cache, then
+** return NULL (do not allocate a new page) if any of the following
+** conditions are true:
+**
+** (a) the number of pages pinned by the cache is greater than
+** PCache1.nMax, or
+**
+** (b) the number of pages pinned by the cache is greater than
+** the sum of nMax for all purgeable caches, less the sum of
+** nMin for all other purgeable caches, or
+**
+** 4. If none of the first three conditions apply and the cache is marked
+** as purgeable, and if one of the following is true:
+**
+** (a) The number of pages allocated for the cache is already
+** PCache1.nMax, or
+**
+** (b) The number of pages allocated for all purgeable caches is
+** already equal to or greater than the sum of nMax for all
+** purgeable caches,
+**
+** (c) The system is under memory pressure and wants to avoid
+** unnecessary pages cache entry allocations
+**
+** then attempt to recycle a page from the LRU list. If it is the right
+** size, return the recycled buffer. Otherwise, free the buffer and
+** proceed to step 5.
+**
+** 5. Otherwise, allocate and return a new page buffer.
+**
+** There are two versions of this routine. pcache1FetchWithMutex() is
+** the general case. pcache1FetchNoMutex() is a faster implementation for
+** the common case where pGroup->mutex is NULL. The pcache1Fetch() wrapper
+** invokes the appropriate routine.
+*/
+static PgHdr1 *pcache1FetchNoMutex(
+ sqlite3_pcache *p,
+ unsigned int iKey,
+ int createFlag
+){
+ PCache1 *pCache = (PCache1 *)p;
+ PgHdr1 *pPage = 0;
+
+ /* Step 1: Search the hash table for an existing entry. */
+ pPage = pCache->apHash[iKey % pCache->nHash];
+ while( pPage && pPage->iKey!=iKey ){ pPage = pPage->pNext; }
+
+ /* Step 2: If the page was found in the hash table, then return it.
+ ** If the page was not in the hash table and createFlag is 0, abort.
+ ** Otherwise (page not in hash and createFlag!=0) continue with
+ ** subsequent steps to try to create the page. */
+ if( pPage ){
+ if( PAGE_IS_UNPINNED(pPage) ){
+ return pcache1PinPage(pPage);
+ }else{
+ return pPage;
+ }
+ }else if( createFlag ){
+ /* Steps 3, 4, and 5 implemented by this subroutine */
+ return pcache1FetchStage2(pCache, iKey, createFlag);
+ }else{
+ return 0;
+ }
+}
+#if PCACHE1_MIGHT_USE_GROUP_MUTEX
+static PgHdr1 *pcache1FetchWithMutex(
+ sqlite3_pcache *p,
+ unsigned int iKey,
+ int createFlag
+){
+ PCache1 *pCache = (PCache1 *)p;
+ PgHdr1 *pPage;
+
+ pcache1EnterMutex(pCache->pGroup);
+ pPage = pcache1FetchNoMutex(p, iKey, createFlag);
+ assert( pPage==0 || pCache->iMaxKey>=iKey );
+ pcache1LeaveMutex(pCache->pGroup);
+ return pPage;
+}
+#endif
+static sqlite3_pcache_page *pcache1Fetch(
+ sqlite3_pcache *p,
+ unsigned int iKey,
+ int createFlag
+){
+#if PCACHE1_MIGHT_USE_GROUP_MUTEX || defined(SQLITE_DEBUG)
+ PCache1 *pCache = (PCache1 *)p;
+#endif
+
+ assert( offsetof(PgHdr1,page)==0 );
+ assert( pCache->bPurgeable || createFlag!=1 );
+ assert( pCache->bPurgeable || pCache->nMin==0 );
+ assert( pCache->bPurgeable==0 || pCache->nMin==10 );
+ assert( pCache->nMin==0 || pCache->bPurgeable );
+ assert( pCache->nHash>0 );
+#if PCACHE1_MIGHT_USE_GROUP_MUTEX
+ if( pCache->pGroup->mutex ){
+ return (sqlite3_pcache_page*)pcache1FetchWithMutex(p, iKey, createFlag);
+ }else
+#endif
+ {
+ return (sqlite3_pcache_page*)pcache1FetchNoMutex(p, iKey, createFlag);
+ }
+}
+
+
+/*
+** Implementation of the sqlite3_pcache.xUnpin method.
+**
+** Mark a page as unpinned (eligible for asynchronous recycling).
+*/
+static void pcache1Unpin(
+ sqlite3_pcache *p,
+ sqlite3_pcache_page *pPg,
+ int reuseUnlikely
+){
+ PCache1 *pCache = (PCache1 *)p;
+ PgHdr1 *pPage = (PgHdr1 *)pPg;
+ PGroup *pGroup = pCache->pGroup;
+
+ assert( pPage->pCache==pCache );
+ pcache1EnterMutex(pGroup);
+
+ /* It is an error to call this function if the page is already
+ ** part of the PGroup LRU list.
+ */
+ assert( pPage->pLruPrev==0 && pPage->pLruNext==0 );
+ assert( PAGE_IS_PINNED(pPage) );
+
+ if( reuseUnlikely || pGroup->nPurgeable>pGroup->nMaxPage ){
+ pcache1RemoveFromHash(pPage, 1);
+ }else{
+ /* Add the page to the PGroup LRU list. */
+ PgHdr1 **ppFirst = &pGroup->lru.pLruNext;
+ pPage->pLruPrev = &pGroup->lru;
+ (pPage->pLruNext = *ppFirst)->pLruPrev = pPage;
+ *ppFirst = pPage;
+ pCache->nRecyclable++;
+ }
+
+ pcache1LeaveMutex(pCache->pGroup);
+}
+
+/*
+** Implementation of the sqlite3_pcache.xRekey method.
+*/
+static void pcache1Rekey(
+ sqlite3_pcache *p,
+ sqlite3_pcache_page *pPg,
+ unsigned int iOld,
+ unsigned int iNew
+){
+ PCache1 *pCache = (PCache1 *)p;
+ PgHdr1 *pPage = (PgHdr1 *)pPg;
+ PgHdr1 **pp;
+ unsigned int h;
+ assert( pPage->iKey==iOld );
+ assert( pPage->pCache==pCache );
+
+ pcache1EnterMutex(pCache->pGroup);
+
+ h = iOld%pCache->nHash;
+ pp = &pCache->apHash[h];
+ while( (*pp)!=pPage ){
+ pp = &(*pp)->pNext;
+ }
+ *pp = pPage->pNext;
+
+ h = iNew%pCache->nHash;
+ pPage->iKey = iNew;
+ pPage->pNext = pCache->apHash[h];
+ pCache->apHash[h] = pPage;
+ if( iNew>pCache->iMaxKey ){
+ pCache->iMaxKey = iNew;
+ }
+
+ pcache1LeaveMutex(pCache->pGroup);
+}
+
+/*
+** Implementation of the sqlite3_pcache.xTruncate method.
+**
+** Discard all unpinned pages in the cache with a page number equal to
+** or greater than parameter iLimit. Any pinned pages with a page number
+** equal to or greater than iLimit are implicitly unpinned.
+*/
+static void pcache1Truncate(sqlite3_pcache *p, unsigned int iLimit){
+ PCache1 *pCache = (PCache1 *)p;
+ pcache1EnterMutex(pCache->pGroup);
+ if( iLimit<=pCache->iMaxKey ){
+ pcache1TruncateUnsafe(pCache, iLimit);
+ pCache->iMaxKey = iLimit-1;
+ }
+ pcache1LeaveMutex(pCache->pGroup);
+}
+
+/*
+** Implementation of the sqlite3_pcache.xDestroy method.
+**
+** Destroy a cache allocated using pcache1Create().
+*/
+static void pcache1Destroy(sqlite3_pcache *p){
+ PCache1 *pCache = (PCache1 *)p;
+ PGroup *pGroup = pCache->pGroup;
+ assert( pCache->bPurgeable || (pCache->nMax==0 && pCache->nMin==0) );
+ pcache1EnterMutex(pGroup);
+ if( pCache->nPage ) pcache1TruncateUnsafe(pCache, 0);
+ assert( pGroup->nMaxPage >= pCache->nMax );
+ pGroup->nMaxPage -= pCache->nMax;
+ assert( pGroup->nMinPage >= pCache->nMin );
+ pGroup->nMinPage -= pCache->nMin;
+ pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
+ pcache1EnforceMaxPage(pCache);
+ pcache1LeaveMutex(pGroup);
+ sqlite3_free(pCache->pBulk);
+ sqlite3_free(pCache->apHash);
+ sqlite3_free(pCache);
+}
+
+/*
+** This function is called during initialization (sqlite3_initialize()) to
+** install the default pluggable cache module, assuming the user has not
+** already provided an alternative.
+*/
+SQLITE_PRIVATE void sqlite3PCacheSetDefault(void){
+ static const sqlite3_pcache_methods2 defaultMethods = {
+ 1, /* iVersion */
+ 0, /* pArg */
+ pcache1Init, /* xInit */
+ pcache1Shutdown, /* xShutdown */
+ pcache1Create, /* xCreate */
+ pcache1Cachesize, /* xCachesize */
+ pcache1Pagecount, /* xPagecount */
+ pcache1Fetch, /* xFetch */
+ pcache1Unpin, /* xUnpin */
+ pcache1Rekey, /* xRekey */
+ pcache1Truncate, /* xTruncate */
+ pcache1Destroy, /* xDestroy */
+ pcache1Shrink /* xShrink */
+ };
+ sqlite3_config(SQLITE_CONFIG_PCACHE2, &defaultMethods);
+}
+
+/*
+** Return the size of the header on each page of this PCACHE implementation.
+*/
+SQLITE_PRIVATE int sqlite3HeaderSizePcache1(void){ return ROUND8(sizeof(PgHdr1)); }
+
+/*
+** Return the global mutex used by this PCACHE implementation. The
+** sqlite3_status() routine needs access to this mutex.
+*/
+SQLITE_PRIVATE sqlite3_mutex *sqlite3Pcache1Mutex(void){
+ return pcache1.mutex;
+}
+
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/*
+** This function is called to free superfluous dynamically allocated memory
+** held by the pager system. Memory in use by any SQLite pager allocated
+** by the current thread may be sqlite3_free()ed.
+**
+** nReq is the number of bytes of memory required. Once this much has
+** been released, the function returns. The return value is the total number
+** of bytes of memory released.
+*/
+SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int nReq){
+ int nFree = 0;
+ assert( sqlite3_mutex_notheld(pcache1.grp.mutex) );
+ assert( sqlite3_mutex_notheld(pcache1.mutex) );
+ if( sqlite3GlobalConfig.pPage==0 ){
+ PgHdr1 *p;
+ pcache1EnterMutex(&pcache1.grp);
+ while( (nReq<0 || nFreeisAnchor==0
+ ){
+ nFree += pcache1MemSize(p->page.pBuf);
+#ifdef SQLITE_PCACHE_SEPARATE_HEADER
+ nFree += sqlite3MemSize(p);
+#endif
+ assert( PAGE_IS_UNPINNED(p) );
+ pcache1PinPage(p);
+ pcache1RemoveFromHash(p, 1);
+ }
+ pcache1LeaveMutex(&pcache1.grp);
+ }
+ return nFree;
+}
+#endif /* SQLITE_ENABLE_MEMORY_MANAGEMENT */
+
+#ifdef SQLITE_TEST
+/*
+** This function is used by test procedures to inspect the internal state
+** of the global cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheStats(
+ int *pnCurrent, /* OUT: Total number of pages cached */
+ int *pnMax, /* OUT: Global maximum cache size */
+ int *pnMin, /* OUT: Sum of PCache1.nMin for purgeable caches */
+ int *pnRecyclable /* OUT: Total number of pages available for recycling */
+){
+ PgHdr1 *p;
+ int nRecyclable = 0;
+ for(p=pcache1.grp.lru.pLruNext; p && !p->isAnchor; p=p->pLruNext){
+ assert( PAGE_IS_UNPINNED(p) );
+ nRecyclable++;
+ }
+ *pnCurrent = pcache1.grp.nPurgeable;
+ *pnMax = (int)pcache1.grp.nMaxPage;
+ *pnMin = (int)pcache1.grp.nMinPage;
+ *pnRecyclable = nRecyclable;
+}
+#endif
+
+/************** End of pcache1.c *********************************************/
+/************** Begin file rowset.c ******************************************/
+/*
+** 2008 December 3
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This module implements an object we call a "RowSet".
+**
+** The RowSet object is a collection of rowids. Rowids
+** are inserted into the RowSet in an arbitrary order. Inserts
+** can be intermixed with tests to see if a given rowid has been
+** previously inserted into the RowSet.
+**
+** After all inserts are finished, it is possible to extract the
+** elements of the RowSet in sorted order. Once this extraction
+** process has started, no new elements may be inserted.
+**
+** Hence, the primitive operations for a RowSet are:
+**
+** CREATE
+** INSERT
+** TEST
+** SMALLEST
+** DESTROY
+**
+** The CREATE and DESTROY primitives are the constructor and destructor,
+** obviously. The INSERT primitive adds a new element to the RowSet.
+** TEST checks to see if an element is already in the RowSet. SMALLEST
+** extracts the least value from the RowSet.
+**
+** The INSERT primitive might allocate additional memory. Memory is
+** allocated in chunks so most INSERTs do no allocation. There is an
+** upper bound on the size of allocated memory. No memory is freed
+** until DESTROY.
+**
+** The TEST primitive includes a "batch" number. The TEST primitive
+** will only see elements that were inserted before the last change
+** in the batch number. In other words, if an INSERT occurs between
+** two TESTs where the TESTs have the same batch nubmer, then the
+** value added by the INSERT will not be visible to the second TEST.
+** The initial batch number is zero, so if the very first TEST contains
+** a non-zero batch number, it will see all prior INSERTs.
+**
+** No INSERTs may occurs after a SMALLEST. An assertion will fail if
+** that is attempted.
+**
+** The cost of an INSERT is roughly constant. (Sometimes new memory
+** has to be allocated on an INSERT.) The cost of a TEST with a new
+** batch number is O(NlogN) where N is the number of elements in the RowSet.
+** The cost of a TEST using the same batch number is O(logN). The cost
+** of the first SMALLEST is O(NlogN). Second and subsequent SMALLEST
+** primitives are constant time. The cost of DESTROY is O(N).
+**
+** TEST and SMALLEST may not be used by the same RowSet. This used to
+** be possible, but the feature was not used, so it was removed in order
+** to simplify the code.
+*/
+/* #include "sqliteInt.h" */
+
+
+/*
+** Target size for allocation chunks.
+*/
+#define ROWSET_ALLOCATION_SIZE 1024
+
+/*
+** The number of rowset entries per allocation chunk.
+*/
+#define ROWSET_ENTRY_PER_CHUNK \
+ ((ROWSET_ALLOCATION_SIZE-8)/sizeof(struct RowSetEntry))
+
+/*
+** Each entry in a RowSet is an instance of the following object.
+**
+** This same object is reused to store a linked list of trees of RowSetEntry
+** objects. In that alternative use, pRight points to the next entry
+** in the list, pLeft points to the tree, and v is unused. The
+** RowSet.pForest value points to the head of this forest list.
+*/
+struct RowSetEntry {
+ i64 v; /* ROWID value for this entry */
+ struct RowSetEntry *pRight; /* Right subtree (larger entries) or list */
+ struct RowSetEntry *pLeft; /* Left subtree (smaller entries) */
+};
+
+/*
+** RowSetEntry objects are allocated in large chunks (instances of the
+** following structure) to reduce memory allocation overhead. The
+** chunks are kept on a linked list so that they can be deallocated
+** when the RowSet is destroyed.
+*/
+struct RowSetChunk {
+ struct RowSetChunk *pNextChunk; /* Next chunk on list of them all */
+ struct RowSetEntry aEntry[ROWSET_ENTRY_PER_CHUNK]; /* Allocated entries */
+};
+
+/*
+** A RowSet in an instance of the following structure.
+**
+** A typedef of this structure if found in sqliteInt.h.
+*/
+struct RowSet {
+ struct RowSetChunk *pChunk; /* List of all chunk allocations */
+ sqlite3 *db; /* The database connection */
+ struct RowSetEntry *pEntry; /* List of entries using pRight */
+ struct RowSetEntry *pLast; /* Last entry on the pEntry list */
+ struct RowSetEntry *pFresh; /* Source of new entry objects */
+ struct RowSetEntry *pForest; /* List of binary trees of entries */
+ u16 nFresh; /* Number of objects on pFresh */
+ u16 rsFlags; /* Various flags */
+ int iBatch; /* Current insert batch */
+};
+
+/*
+** Allowed values for RowSet.rsFlags
+*/
+#define ROWSET_SORTED 0x01 /* True if RowSet.pEntry is sorted */
+#define ROWSET_NEXT 0x02 /* True if sqlite3RowSetNext() has been called */
+
+/*
+** Allocate a RowSet object. Return NULL if a memory allocation
+** error occurs.
+*/
+SQLITE_PRIVATE RowSet *sqlite3RowSetInit(sqlite3 *db){
+ RowSet *p = sqlite3DbMallocRawNN(db, sizeof(*p));
+ if( p ){
+ int N = sqlite3DbMallocSize(db, p);
+ p->pChunk = 0;
+ p->db = db;
+ p->pEntry = 0;
+ p->pLast = 0;
+ p->pForest = 0;
+ p->pFresh = (struct RowSetEntry*)(ROUND8(sizeof(*p)) + (char*)p);
+ p->nFresh = (u16)((N - ROUND8(sizeof(*p)))/sizeof(struct RowSetEntry));
+ p->rsFlags = ROWSET_SORTED;
+ p->iBatch = 0;
+ }
+ return p;
+}
+
+/*
+** Deallocate all chunks from a RowSet. This frees all memory that
+** the RowSet has allocated over its lifetime. This routine is
+** the destructor for the RowSet.
+*/
+SQLITE_PRIVATE void sqlite3RowSetClear(void *pArg){
+ RowSet *p = (RowSet*)pArg;
+ struct RowSetChunk *pChunk, *pNextChunk;
+ for(pChunk=p->pChunk; pChunk; pChunk = pNextChunk){
+ pNextChunk = pChunk->pNextChunk;
+ sqlite3DbFree(p->db, pChunk);
+ }
+ p->pChunk = 0;
+ p->nFresh = 0;
+ p->pEntry = 0;
+ p->pLast = 0;
+ p->pForest = 0;
+ p->rsFlags = ROWSET_SORTED;
+}
+
+/*
+** Deallocate all chunks from a RowSet. This frees all memory that
+** the RowSet has allocated over its lifetime. This routine is
+** the destructor for the RowSet.
+*/
+SQLITE_PRIVATE void sqlite3RowSetDelete(void *pArg){
+ sqlite3RowSetClear(pArg);
+ sqlite3DbFree(((RowSet*)pArg)->db, pArg);
+}
+
+/*
+** Allocate a new RowSetEntry object that is associated with the
+** given RowSet. Return a pointer to the new and completely uninitialized
+** objected.
+**
+** In an OOM situation, the RowSet.db->mallocFailed flag is set and this
+** routine returns NULL.
+*/
+static struct RowSetEntry *rowSetEntryAlloc(RowSet *p){
+ assert( p!=0 );
+ if( p->nFresh==0 ){ /*OPTIMIZATION-IF-FALSE*/
+ /* We could allocate a fresh RowSetEntry each time one is needed, but it
+ ** is more efficient to pull a preallocated entry from the pool */
+ struct RowSetChunk *pNew;
+ pNew = sqlite3DbMallocRawNN(p->db, sizeof(*pNew));
+ if( pNew==0 ){
+ return 0;
+ }
+ pNew->pNextChunk = p->pChunk;
+ p->pChunk = pNew;
+ p->pFresh = pNew->aEntry;
+ p->nFresh = ROWSET_ENTRY_PER_CHUNK;
+ }
+ p->nFresh--;
+ return p->pFresh++;
+}
+
+/*
+** Insert a new value into a RowSet.
+**
+** The mallocFailed flag of the database connection is set if a
+** memory allocation fails.
+*/
+SQLITE_PRIVATE void sqlite3RowSetInsert(RowSet *p, i64 rowid){
+ struct RowSetEntry *pEntry; /* The new entry */
+ struct RowSetEntry *pLast; /* The last prior entry */
+
+ /* This routine is never called after sqlite3RowSetNext() */
+ assert( p!=0 && (p->rsFlags & ROWSET_NEXT)==0 );
+
+ pEntry = rowSetEntryAlloc(p);
+ if( pEntry==0 ) return;
+ pEntry->v = rowid;
+ pEntry->pRight = 0;
+ pLast = p->pLast;
+ if( pLast ){
+ if( rowid<=pLast->v ){ /*OPTIMIZATION-IF-FALSE*/
+ /* Avoid unnecessary sorts by preserving the ROWSET_SORTED flags
+ ** where possible */
+ p->rsFlags &= ~ROWSET_SORTED;
+ }
+ pLast->pRight = pEntry;
+ }else{
+ p->pEntry = pEntry;
+ }
+ p->pLast = pEntry;
+}
+
+/*
+** Merge two lists of RowSetEntry objects. Remove duplicates.
+**
+** The input lists are connected via pRight pointers and are
+** assumed to each already be in sorted order.
+*/
+static struct RowSetEntry *rowSetEntryMerge(
+ struct RowSetEntry *pA, /* First sorted list to be merged */
+ struct RowSetEntry *pB /* Second sorted list to be merged */
+){
+ struct RowSetEntry head;
+ struct RowSetEntry *pTail;
+
+ pTail = &head;
+ assert( pA!=0 && pB!=0 );
+ for(;;){
+ assert( pA->pRight==0 || pA->v<=pA->pRight->v );
+ assert( pB->pRight==0 || pB->v<=pB->pRight->v );
+ if( pA->v<=pB->v ){
+ if( pA->vv ) pTail = pTail->pRight = pA;
+ pA = pA->pRight;
+ if( pA==0 ){
+ pTail->pRight = pB;
+ break;
+ }
+ }else{
+ pTail = pTail->pRight = pB;
+ pB = pB->pRight;
+ if( pB==0 ){
+ pTail->pRight = pA;
+ break;
+ }
+ }
+ }
+ return head.pRight;
+}
+
+/*
+** Sort all elements on the list of RowSetEntry objects into order of
+** increasing v.
+*/
+static struct RowSetEntry *rowSetEntrySort(struct RowSetEntry *pIn){
+ unsigned int i;
+ struct RowSetEntry *pNext, *aBucket[40];
+
+ memset(aBucket, 0, sizeof(aBucket));
+ while( pIn ){
+ pNext = pIn->pRight;
+ pIn->pRight = 0;
+ for(i=0; aBucket[i]; i++){
+ pIn = rowSetEntryMerge(aBucket[i], pIn);
+ aBucket[i] = 0;
+ }
+ aBucket[i] = pIn;
+ pIn = pNext;
+ }
+ pIn = aBucket[0];
+ for(i=1; ipLeft ){
+ struct RowSetEntry *p;
+ rowSetTreeToList(pIn->pLeft, ppFirst, &p);
+ p->pRight = pIn;
+ }else{
+ *ppFirst = pIn;
+ }
+ if( pIn->pRight ){
+ rowSetTreeToList(pIn->pRight, &pIn->pRight, ppLast);
+ }else{
+ *ppLast = pIn;
+ }
+ assert( (*ppLast)->pRight==0 );
+}
+
+
+/*
+** Convert a sorted list of elements (connected by pRight) into a binary
+** tree with depth of iDepth. A depth of 1 means the tree contains a single
+** node taken from the head of *ppList. A depth of 2 means a tree with
+** three nodes. And so forth.
+**
+** Use as many entries from the input list as required and update the
+** *ppList to point to the unused elements of the list. If the input
+** list contains too few elements, then construct an incomplete tree
+** and leave *ppList set to NULL.
+**
+** Return a pointer to the root of the constructed binary tree.
+*/
+static struct RowSetEntry *rowSetNDeepTree(
+ struct RowSetEntry **ppList,
+ int iDepth
+){
+ struct RowSetEntry *p; /* Root of the new tree */
+ struct RowSetEntry *pLeft; /* Left subtree */
+ if( *ppList==0 ){ /*OPTIMIZATION-IF-TRUE*/
+ /* Prevent unnecessary deep recursion when we run out of entries */
+ return 0;
+ }
+ if( iDepth>1 ){ /*OPTIMIZATION-IF-TRUE*/
+ /* This branch causes a *balanced* tree to be generated. A valid tree
+ ** is still generated without this branch, but the tree is wildly
+ ** unbalanced and inefficient. */
+ pLeft = rowSetNDeepTree(ppList, iDepth-1);
+ p = *ppList;
+ if( p==0 ){ /*OPTIMIZATION-IF-FALSE*/
+ /* It is safe to always return here, but the resulting tree
+ ** would be unbalanced */
+ return pLeft;
+ }
+ p->pLeft = pLeft;
+ *ppList = p->pRight;
+ p->pRight = rowSetNDeepTree(ppList, iDepth-1);
+ }else{
+ p = *ppList;
+ *ppList = p->pRight;
+ p->pLeft = p->pRight = 0;
+ }
+ return p;
+}
+
+/*
+** Convert a sorted list of elements into a binary tree. Make the tree
+** as deep as it needs to be in order to contain the entire list.
+*/
+static struct RowSetEntry *rowSetListToTree(struct RowSetEntry *pList){
+ int iDepth; /* Depth of the tree so far */
+ struct RowSetEntry *p; /* Current tree root */
+ struct RowSetEntry *pLeft; /* Left subtree */
+
+ assert( pList!=0 );
+ p = pList;
+ pList = p->pRight;
+ p->pLeft = p->pRight = 0;
+ for(iDepth=1; pList; iDepth++){
+ pLeft = p;
+ p = pList;
+ pList = p->pRight;
+ p->pLeft = pLeft;
+ p->pRight = rowSetNDeepTree(&pList, iDepth);
+ }
+ return p;
+}
+
+/*
+** Extract the smallest element from the RowSet.
+** Write the element into *pRowid. Return 1 on success. Return
+** 0 if the RowSet is already empty.
+**
+** After this routine has been called, the sqlite3RowSetInsert()
+** routine may not be called again.
+**
+** This routine may not be called after sqlite3RowSetTest() has
+** been used. Older versions of RowSet allowed that, but as the
+** capability was not used by the code generator, it was removed
+** for code economy.
+*/
+SQLITE_PRIVATE int sqlite3RowSetNext(RowSet *p, i64 *pRowid){
+ assert( p!=0 );
+ assert( p->pForest==0 ); /* Cannot be used with sqlite3RowSetText() */
+
+ /* Merge the forest into a single sorted list on first call */
+ if( (p->rsFlags & ROWSET_NEXT)==0 ){ /*OPTIMIZATION-IF-FALSE*/
+ if( (p->rsFlags & ROWSET_SORTED)==0 ){ /*OPTIMIZATION-IF-FALSE*/
+ p->pEntry = rowSetEntrySort(p->pEntry);
+ }
+ p->rsFlags |= ROWSET_SORTED|ROWSET_NEXT;
+ }
+
+ /* Return the next entry on the list */
+ if( p->pEntry ){
+ *pRowid = p->pEntry->v;
+ p->pEntry = p->pEntry->pRight;
+ if( p->pEntry==0 ){ /*OPTIMIZATION-IF-TRUE*/
+ /* Free memory immediately, rather than waiting on sqlite3_finalize() */
+ sqlite3RowSetClear(p);
+ }
+ return 1;
+ }else{
+ return 0;
+ }
+}
+
+/*
+** Check to see if element iRowid was inserted into the rowset as
+** part of any insert batch prior to iBatch. Return 1 or 0.
+**
+** If this is the first test of a new batch and if there exist entries
+** on pRowSet->pEntry, then sort those entries into the forest at
+** pRowSet->pForest so that they can be tested.
+*/
+SQLITE_PRIVATE int sqlite3RowSetTest(RowSet *pRowSet, int iBatch, sqlite3_int64 iRowid){
+ struct RowSetEntry *p, *pTree;
+
+ /* This routine is never called after sqlite3RowSetNext() */
+ assert( pRowSet!=0 && (pRowSet->rsFlags & ROWSET_NEXT)==0 );
+
+ /* Sort entries into the forest on the first test of a new batch.
+ ** To save unnecessary work, only do this when the batch number changes.
+ */
+ if( iBatch!=pRowSet->iBatch ){ /*OPTIMIZATION-IF-FALSE*/
+ p = pRowSet->pEntry;
+ if( p ){
+ struct RowSetEntry **ppPrevTree = &pRowSet->pForest;
+ if( (pRowSet->rsFlags & ROWSET_SORTED)==0 ){ /*OPTIMIZATION-IF-FALSE*/
+ /* Only sort the current set of entiries if they need it */
+ p = rowSetEntrySort(p);
+ }
+ for(pTree = pRowSet->pForest; pTree; pTree=pTree->pRight){
+ ppPrevTree = &pTree->pRight;
+ if( pTree->pLeft==0 ){
+ pTree->pLeft = rowSetListToTree(p);
+ break;
+ }else{
+ struct RowSetEntry *pAux, *pTail;
+ rowSetTreeToList(pTree->pLeft, &pAux, &pTail);
+ pTree->pLeft = 0;
+ p = rowSetEntryMerge(pAux, p);
+ }
+ }
+ if( pTree==0 ){
+ *ppPrevTree = pTree = rowSetEntryAlloc(pRowSet);
+ if( pTree ){
+ pTree->v = 0;
+ pTree->pRight = 0;
+ pTree->pLeft = rowSetListToTree(p);
+ }
+ }
+ pRowSet->pEntry = 0;
+ pRowSet->pLast = 0;
+ pRowSet->rsFlags |= ROWSET_SORTED;
+ }
+ pRowSet->iBatch = iBatch;
+ }
+
+ /* Test to see if the iRowid value appears anywhere in the forest.
+ ** Return 1 if it does and 0 if not.
+ */
+ for(pTree = pRowSet->pForest; pTree; pTree=pTree->pRight){
+ p = pTree->pLeft;
+ while( p ){
+ if( p->vpRight;
+ }else if( p->v>iRowid ){
+ p = p->pLeft;
+ }else{
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+
+/************** End of rowset.c **********************************************/
+/************** Begin file pager.c *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the implementation of the page cache subsystem or "pager".
+**
+** The pager is used to access a database disk file. It implements
+** atomic commit and rollback through the use of a journal file that
+** is separate from the database file. The pager also implements file
+** locking to prevent two processes from writing the same database
+** file simultaneously, or one process from reading the database while
+** another is writing.
+*/
+#ifndef SQLITE_OMIT_DISKIO
+/* #include "sqliteInt.h" */
+/************** Include wal.h in the middle of pager.c ***********************/
+/************** Begin file wal.h *********************************************/
+/*
+** 2010 February 1
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface to the write-ahead logging
+** system. Refer to the comments below and the header comment attached to
+** the implementation of each function in log.c for further details.
+*/
+
+#ifndef SQLITE_WAL_H
+#define SQLITE_WAL_H
+
+/* #include "sqliteInt.h" */
+
+/* Macros for extracting appropriate sync flags for either transaction
+** commits (WAL_SYNC_FLAGS(X)) or for checkpoint ops (CKPT_SYNC_FLAGS(X)):
+*/
+#define WAL_SYNC_FLAGS(X) ((X)&0x03)
+#define CKPT_SYNC_FLAGS(X) (((X)>>2)&0x03)
+
+#ifdef SQLITE_OMIT_WAL
+# define sqlite3WalOpen(x,y,z) 0
+# define sqlite3WalLimit(x,y)
+# define sqlite3WalClose(v,w,x,y,z) 0
+# define sqlite3WalBeginReadTransaction(y,z) 0
+# define sqlite3WalEndReadTransaction(z)
+# define sqlite3WalDbsize(y) 0
+# define sqlite3WalBeginWriteTransaction(y) 0
+# define sqlite3WalEndWriteTransaction(x) 0
+# define sqlite3WalUndo(x,y,z) 0
+# define sqlite3WalSavepoint(y,z)
+# define sqlite3WalSavepointUndo(y,z) 0
+# define sqlite3WalFrames(u,v,w,x,y,z) 0
+# define sqlite3WalCheckpoint(q,r,s,t,u,v,w,x,y,z) 0
+# define sqlite3WalCallback(z) 0
+# define sqlite3WalExclusiveMode(y,z) 0
+# define sqlite3WalHeapMemory(z) 0
+# define sqlite3WalFramesize(z) 0
+# define sqlite3WalFindFrame(x,y,z) 0
+# define sqlite3WalFile(x) 0
+#else
+
+#define WAL_SAVEPOINT_NDATA 4
+
+/* Connection to a write-ahead log (WAL) file.
+** There is one object of this type for each pager.
+*/
+typedef struct Wal Wal;
+
+/* Open and close a connection to a write-ahead log. */
+SQLITE_PRIVATE int sqlite3WalOpen(sqlite3_vfs*, sqlite3_file*, const char *, int, i64, Wal**);
+SQLITE_PRIVATE int sqlite3WalClose(Wal *pWal, sqlite3*, int sync_flags, int, u8 *);
+
+/* Set the limiting size of a WAL file. */
+SQLITE_PRIVATE void sqlite3WalLimit(Wal*, i64);
+
+/* Used by readers to open (lock) and close (unlock) a snapshot. A
+** snapshot is like a read-transaction. It is the state of the database
+** at an instant in time. sqlite3WalOpenSnapshot gets a read lock and
+** preserves the current state even if the other threads or processes
+** write to or checkpoint the WAL. sqlite3WalCloseSnapshot() closes the
+** transaction and releases the lock.
+*/
+SQLITE_PRIVATE int sqlite3WalBeginReadTransaction(Wal *pWal, int *);
+SQLITE_PRIVATE void sqlite3WalEndReadTransaction(Wal *pWal);
+
+/* Read a page from the write-ahead log, if it is present. */
+SQLITE_PRIVATE int sqlite3WalFindFrame(Wal *, Pgno, u32 *);
+SQLITE_PRIVATE int sqlite3WalReadFrame(Wal *, u32, int, u8 *);
+
+/* If the WAL is not empty, return the size of the database. */
+SQLITE_PRIVATE Pgno sqlite3WalDbsize(Wal *pWal);
+
+/* Obtain or release the WRITER lock. */
+SQLITE_PRIVATE int sqlite3WalBeginWriteTransaction(Wal *pWal);
+SQLITE_PRIVATE int sqlite3WalEndWriteTransaction(Wal *pWal);
+
+/* Undo any frames written (but not committed) to the log */
+SQLITE_PRIVATE int sqlite3WalUndo(Wal *pWal, int (*xUndo)(void *, Pgno), void *pUndoCtx);
+
+/* Return an integer that records the current (uncommitted) write
+** position in the WAL */
+SQLITE_PRIVATE void sqlite3WalSavepoint(Wal *pWal, u32 *aWalData);
+
+/* Move the write position of the WAL back to iFrame. Called in
+** response to a ROLLBACK TO command. */
+SQLITE_PRIVATE int sqlite3WalSavepointUndo(Wal *pWal, u32 *aWalData);
+
+/* Write a frame or frames to the log. */
+SQLITE_PRIVATE int sqlite3WalFrames(Wal *pWal, int, PgHdr *, Pgno, int, int);
+
+/* Copy pages from the log to the database file */
+SQLITE_PRIVATE int sqlite3WalCheckpoint(
+ Wal *pWal, /* Write-ahead log connection */
+ sqlite3 *db, /* Check this handle's interrupt flag */
+ int eMode, /* One of PASSIVE, FULL and RESTART */
+ int (*xBusy)(void*), /* Function to call when busy */
+ void *pBusyArg, /* Context argument for xBusyHandler */
+ int sync_flags, /* Flags to sync db file with (or 0) */
+ int nBuf, /* Size of buffer nBuf */
+ u8 *zBuf, /* Temporary buffer to use */
+ int *pnLog, /* OUT: Number of frames in WAL */
+ int *pnCkpt /* OUT: Number of backfilled frames in WAL */
+);
+
+/* Return the value to pass to a sqlite3_wal_hook callback, the
+** number of frames in the WAL at the point of the last commit since
+** sqlite3WalCallback() was called. If no commits have occurred since
+** the last call, then return 0.
+*/
+SQLITE_PRIVATE int sqlite3WalCallback(Wal *pWal);
+
+/* Tell the wal layer that an EXCLUSIVE lock has been obtained (or released)
+** by the pager layer on the database file.
+*/
+SQLITE_PRIVATE int sqlite3WalExclusiveMode(Wal *pWal, int op);
+
+/* Return true if the argument is non-NULL and the WAL module is using
+** heap-memory for the wal-index. Otherwise, if the argument is NULL or the
+** WAL module is using shared-memory, return false.
+*/
+SQLITE_PRIVATE int sqlite3WalHeapMemory(Wal *pWal);
+
+#ifdef SQLITE_ENABLE_SNAPSHOT
+SQLITE_PRIVATE int sqlite3WalSnapshotGet(Wal *pWal, sqlite3_snapshot **ppSnapshot);
+SQLITE_PRIVATE void sqlite3WalSnapshotOpen(Wal *pWal, sqlite3_snapshot *pSnapshot);
+SQLITE_PRIVATE int sqlite3WalSnapshotRecover(Wal *pWal);
+SQLITE_PRIVATE int sqlite3WalSnapshotCheck(Wal *pWal, sqlite3_snapshot *pSnapshot);
+SQLITE_PRIVATE void sqlite3WalSnapshotUnlock(Wal *pWal);
+#endif
+
+#ifdef SQLITE_ENABLE_ZIPVFS
+/* If the WAL file is not empty, return the number of bytes of content
+** stored in each frame (i.e. the db page-size when the WAL was created).
+*/
+SQLITE_PRIVATE int sqlite3WalFramesize(Wal *pWal);
+#endif
+
+/* Return the sqlite3_file object for the WAL file */
+SQLITE_PRIVATE sqlite3_file *sqlite3WalFile(Wal *pWal);
+
+#endif /* ifndef SQLITE_OMIT_WAL */
+#endif /* SQLITE_WAL_H */
+
+/************** End of wal.h *************************************************/
+/************** Continuing where we left off in pager.c **********************/
+
+
+/******************* NOTES ON THE DESIGN OF THE PAGER ************************
+**
+** This comment block describes invariants that hold when using a rollback
+** journal. These invariants do not apply for journal_mode=WAL,
+** journal_mode=MEMORY, or journal_mode=OFF.
+**
+** Within this comment block, a page is deemed to have been synced
+** automatically as soon as it is written when PRAGMA synchronous=OFF.
+** Otherwise, the page is not synced until the xSync method of the VFS
+** is called successfully on the file containing the page.
+**
+** Definition: A page of the database file is said to be "overwriteable" if
+** one or more of the following are true about the page:
+**
+** (a) The original content of the page as it was at the beginning of
+** the transaction has been written into the rollback journal and
+** synced.
+**
+** (b) The page was a freelist leaf page at the start of the transaction.
+**
+** (c) The page number is greater than the largest page that existed in
+** the database file at the start of the transaction.
+**
+** (1) A page of the database file is never overwritten unless one of the
+** following are true:
+**
+** (a) The page and all other pages on the same sector are overwriteable.
+**
+** (b) The atomic page write optimization is enabled, and the entire
+** transaction other than the update of the transaction sequence
+** number consists of a single page change.
+**
+** (2) The content of a page written into the rollback journal exactly matches
+** both the content in the database when the rollback journal was written
+** and the content in the database at the beginning of the current
+** transaction.
+**
+** (3) Writes to the database file are an integer multiple of the page size
+** in length and are aligned on a page boundary.
+**
+** (4) Reads from the database file are either aligned on a page boundary and
+** an integer multiple of the page size in length or are taken from the
+** first 100 bytes of the database file.
+**
+** (5) All writes to the database file are synced prior to the rollback journal
+** being deleted, truncated, or zeroed.
+**
+** (6) If a master journal file is used, then all writes to the database file
+** are synced prior to the master journal being deleted.
+**
+** Definition: Two databases (or the same database at two points it time)
+** are said to be "logically equivalent" if they give the same answer to
+** all queries. Note in particular the content of freelist leaf
+** pages can be changed arbitrarily without affecting the logical equivalence
+** of the database.
+**
+** (7) At any time, if any subset, including the empty set and the total set,
+** of the unsynced changes to a rollback journal are removed and the
+** journal is rolled back, the resulting database file will be logically
+** equivalent to the database file at the beginning of the transaction.
+**
+** (8) When a transaction is rolled back, the xTruncate method of the VFS
+** is called to restore the database file to the same size it was at
+** the beginning of the transaction. (In some VFSes, the xTruncate
+** method is a no-op, but that does not change the fact the SQLite will
+** invoke it.)
+**
+** (9) Whenever the database file is modified, at least one bit in the range
+** of bytes from 24 through 39 inclusive will be changed prior to releasing
+** the EXCLUSIVE lock, thus signaling other connections on the same
+** database to flush their caches.
+**
+** (10) The pattern of bits in bytes 24 through 39 shall not repeat in less
+** than one billion transactions.
+**
+** (11) A database file is well-formed at the beginning and at the conclusion
+** of every transaction.
+**
+** (12) An EXCLUSIVE lock is held on the database file when writing to
+** the database file.
+**
+** (13) A SHARED lock is held on the database file while reading any
+** content out of the database file.
+**
+******************************************************************************/
+
+/*
+** Macros for troubleshooting. Normally turned off
+*/
+#if 0
+int sqlite3PagerTrace=1; /* True to enable tracing */
+#define sqlite3DebugPrintf printf
+#define PAGERTRACE(X) if( sqlite3PagerTrace ){ sqlite3DebugPrintf X; }
+#else
+#define PAGERTRACE(X)
+#endif
+
+/*
+** The following two macros are used within the PAGERTRACE() macros above
+** to print out file-descriptors.
+**
+** PAGERID() takes a pointer to a Pager struct as its argument. The
+** associated file-descriptor is returned. FILEHANDLEID() takes an sqlite3_file
+** struct as its argument.
+*/
+#define PAGERID(p) (SQLITE_PTR_TO_INT(p->fd))
+#define FILEHANDLEID(fd) (SQLITE_PTR_TO_INT(fd))
+
+/*
+** The Pager.eState variable stores the current 'state' of a pager. A
+** pager may be in any one of the seven states shown in the following
+** state diagram.
+**
+** OPEN <------+------+
+** | | |
+** V | |
+** +---------> READER-------+ |
+** | | |
+** | V |
+** |<-------WRITER_LOCKED------> ERROR
+** | | ^
+** | V |
+** |<------WRITER_CACHEMOD-------->|
+** | | |
+** | V |
+** |<-------WRITER_DBMOD---------->|
+** | | |
+** | V |
+** +<------WRITER_FINISHED-------->+
+**
+**
+** List of state transitions and the C [function] that performs each:
+**
+** OPEN -> READER [sqlite3PagerSharedLock]
+** READER -> OPEN [pager_unlock]
+**
+** READER -> WRITER_LOCKED [sqlite3PagerBegin]
+** WRITER_LOCKED -> WRITER_CACHEMOD [pager_open_journal]
+** WRITER_CACHEMOD -> WRITER_DBMOD [syncJournal]
+** WRITER_DBMOD -> WRITER_FINISHED [sqlite3PagerCommitPhaseOne]
+** WRITER_*** -> READER [pager_end_transaction]
+**
+** WRITER_*** -> ERROR [pager_error]
+** ERROR -> OPEN [pager_unlock]
+**
+**
+** OPEN:
+**
+** The pager starts up in this state. Nothing is guaranteed in this
+** state - the file may or may not be locked and the database size is
+** unknown. The database may not be read or written.
+**
+** * No read or write transaction is active.
+** * Any lock, or no lock at all, may be held on the database file.
+** * The dbSize, dbOrigSize and dbFileSize variables may not be trusted.
+**
+** READER:
+**
+** In this state all the requirements for reading the database in
+** rollback (non-WAL) mode are met. Unless the pager is (or recently
+** was) in exclusive-locking mode, a user-level read transaction is
+** open. The database size is known in this state.
+**
+** A connection running with locking_mode=normal enters this state when
+** it opens a read-transaction on the database and returns to state
+** OPEN after the read-transaction is completed. However a connection
+** running in locking_mode=exclusive (including temp databases) remains in
+** this state even after the read-transaction is closed. The only way
+** a locking_mode=exclusive connection can transition from READER to OPEN
+** is via the ERROR state (see below).
+**
+** * A read transaction may be active (but a write-transaction cannot).
+** * A SHARED or greater lock is held on the database file.
+** * The dbSize variable may be trusted (even if a user-level read
+** transaction is not active). The dbOrigSize and dbFileSize variables
+** may not be trusted at this point.
+** * If the database is a WAL database, then the WAL connection is open.
+** * Even if a read-transaction is not open, it is guaranteed that
+** there is no hot-journal in the file-system.
+**
+** WRITER_LOCKED:
+**
+** The pager moves to this state from READER when a write-transaction
+** is first opened on the database. In WRITER_LOCKED state, all locks
+** required to start a write-transaction are held, but no actual
+** modifications to the cache or database have taken place.
+**
+** In rollback mode, a RESERVED or (if the transaction was opened with
+** BEGIN EXCLUSIVE) EXCLUSIVE lock is obtained on the database file when
+** moving to this state, but the journal file is not written to or opened
+** to in this state. If the transaction is committed or rolled back while
+** in WRITER_LOCKED state, all that is required is to unlock the database
+** file.
+**
+** IN WAL mode, WalBeginWriteTransaction() is called to lock the log file.
+** If the connection is running with locking_mode=exclusive, an attempt
+** is made to obtain an EXCLUSIVE lock on the database file.
+**
+** * A write transaction is active.
+** * If the connection is open in rollback-mode, a RESERVED or greater
+** lock is held on the database file.
+** * If the connection is open in WAL-mode, a WAL write transaction
+** is open (i.e. sqlite3WalBeginWriteTransaction() has been successfully
+** called).
+** * The dbSize, dbOrigSize and dbFileSize variables are all valid.
+** * The contents of the pager cache have not been modified.
+** * The journal file may or may not be open.
+** * Nothing (not even the first header) has been written to the journal.
+**
+** WRITER_CACHEMOD:
+**
+** A pager moves from WRITER_LOCKED state to this state when a page is
+** first modified by the upper layer. In rollback mode the journal file
+** is opened (if it is not already open) and a header written to the
+** start of it. The database file on disk has not been modified.
+**
+** * A write transaction is active.
+** * A RESERVED or greater lock is held on the database file.
+** * The journal file is open and the first header has been written
+** to it, but the header has not been synced to disk.
+** * The contents of the page cache have been modified.
+**
+** WRITER_DBMOD:
+**
+** The pager transitions from WRITER_CACHEMOD into WRITER_DBMOD state
+** when it modifies the contents of the database file. WAL connections
+** never enter this state (since they do not modify the database file,
+** just the log file).
+**
+** * A write transaction is active.
+** * An EXCLUSIVE or greater lock is held on the database file.
+** * The journal file is open and the first header has been written
+** and synced to disk.
+** * The contents of the page cache have been modified (and possibly
+** written to disk).
+**
+** WRITER_FINISHED:
+**
+** It is not possible for a WAL connection to enter this state.
+**
+** A rollback-mode pager changes to WRITER_FINISHED state from WRITER_DBMOD
+** state after the entire transaction has been successfully written into the
+** database file. In this state the transaction may be committed simply
+** by finalizing the journal file. Once in WRITER_FINISHED state, it is
+** not possible to modify the database further. At this point, the upper
+** layer must either commit or rollback the transaction.
+**
+** * A write transaction is active.
+** * An EXCLUSIVE or greater lock is held on the database file.
+** * All writing and syncing of journal and database data has finished.
+** If no error occurred, all that remains is to finalize the journal to
+** commit the transaction. If an error did occur, the caller will need
+** to rollback the transaction.
+**
+** ERROR:
+**
+** The ERROR state is entered when an IO or disk-full error (including
+** SQLITE_IOERR_NOMEM) occurs at a point in the code that makes it
+** difficult to be sure that the in-memory pager state (cache contents,
+** db size etc.) are consistent with the contents of the file-system.
+**
+** Temporary pager files may enter the ERROR state, but in-memory pagers
+** cannot.
+**
+** For example, if an IO error occurs while performing a rollback,
+** the contents of the page-cache may be left in an inconsistent state.
+** At this point it would be dangerous to change back to READER state
+** (as usually happens after a rollback). Any subsequent readers might
+** report database corruption (due to the inconsistent cache), and if
+** they upgrade to writers, they may inadvertently corrupt the database
+** file. To avoid this hazard, the pager switches into the ERROR state
+** instead of READER following such an error.
+**
+** Once it has entered the ERROR state, any attempt to use the pager
+** to read or write data returns an error. Eventually, once all
+** outstanding transactions have been abandoned, the pager is able to
+** transition back to OPEN state, discarding the contents of the
+** page-cache and any other in-memory state at the same time. Everything
+** is reloaded from disk (and, if necessary, hot-journal rollback peformed)
+** when a read-transaction is next opened on the pager (transitioning
+** the pager into READER state). At that point the system has recovered
+** from the error.
+**
+** Specifically, the pager jumps into the ERROR state if:
+**
+** 1. An error occurs while attempting a rollback. This happens in
+** function sqlite3PagerRollback().
+**
+** 2. An error occurs while attempting to finalize a journal file
+** following a commit in function sqlite3PagerCommitPhaseTwo().
+**
+** 3. An error occurs while attempting to write to the journal or
+** database file in function pagerStress() in order to free up
+** memory.
+**
+** In other cases, the error is returned to the b-tree layer. The b-tree
+** layer then attempts a rollback operation. If the error condition
+** persists, the pager enters the ERROR state via condition (1) above.
+**
+** Condition (3) is necessary because it can be triggered by a read-only
+** statement executed within a transaction. In this case, if the error
+** code were simply returned to the user, the b-tree layer would not
+** automatically attempt a rollback, as it assumes that an error in a
+** read-only statement cannot leave the pager in an internally inconsistent
+** state.
+**
+** * The Pager.errCode variable is set to something other than SQLITE_OK.
+** * There are one or more outstanding references to pages (after the
+** last reference is dropped the pager should move back to OPEN state).
+** * The pager is not an in-memory pager.
+**
+**
+** Notes:
+**
+** * A pager is never in WRITER_DBMOD or WRITER_FINISHED state if the
+** connection is open in WAL mode. A WAL connection is always in one
+** of the first four states.
+**
+** * Normally, a connection open in exclusive mode is never in PAGER_OPEN
+** state. There are two exceptions: immediately after exclusive-mode has
+** been turned on (and before any read or write transactions are
+** executed), and when the pager is leaving the "error state".
+**
+** * See also: assert_pager_state().
+*/
+#define PAGER_OPEN 0
+#define PAGER_READER 1
+#define PAGER_WRITER_LOCKED 2
+#define PAGER_WRITER_CACHEMOD 3
+#define PAGER_WRITER_DBMOD 4
+#define PAGER_WRITER_FINISHED 5
+#define PAGER_ERROR 6
+
+/*
+** The Pager.eLock variable is almost always set to one of the
+** following locking-states, according to the lock currently held on
+** the database file: NO_LOCK, SHARED_LOCK, RESERVED_LOCK or EXCLUSIVE_LOCK.
+** This variable is kept up to date as locks are taken and released by
+** the pagerLockDb() and pagerUnlockDb() wrappers.
+**
+** If the VFS xLock() or xUnlock() returns an error other than SQLITE_BUSY
+** (i.e. one of the SQLITE_IOERR subtypes), it is not clear whether or not
+** the operation was successful. In these circumstances pagerLockDb() and
+** pagerUnlockDb() take a conservative approach - eLock is always updated
+** when unlocking the file, and only updated when locking the file if the
+** VFS call is successful. This way, the Pager.eLock variable may be set
+** to a less exclusive (lower) value than the lock that is actually held
+** at the system level, but it is never set to a more exclusive value.
+**
+** This is usually safe. If an xUnlock fails or appears to fail, there may
+** be a few redundant xLock() calls or a lock may be held for longer than
+** required, but nothing really goes wrong.
+**
+** The exception is when the database file is unlocked as the pager moves
+** from ERROR to OPEN state. At this point there may be a hot-journal file
+** in the file-system that needs to be rolled back (as part of an OPEN->SHARED
+** transition, by the same pager or any other). If the call to xUnlock()
+** fails at this point and the pager is left holding an EXCLUSIVE lock, this
+** can confuse the call to xCheckReservedLock() call made later as part
+** of hot-journal detection.
+**
+** xCheckReservedLock() is defined as returning true "if there is a RESERVED
+** lock held by this process or any others". So xCheckReservedLock may
+** return true because the caller itself is holding an EXCLUSIVE lock (but
+** doesn't know it because of a previous error in xUnlock). If this happens
+** a hot-journal may be mistaken for a journal being created by an active
+** transaction in another process, causing SQLite to read from the database
+** without rolling it back.
+**
+** To work around this, if a call to xUnlock() fails when unlocking the
+** database in the ERROR state, Pager.eLock is set to UNKNOWN_LOCK. It
+** is only changed back to a real locking state after a successful call
+** to xLock(EXCLUSIVE). Also, the code to do the OPEN->SHARED state transition
+** omits the check for a hot-journal if Pager.eLock is set to UNKNOWN_LOCK
+** lock. Instead, it assumes a hot-journal exists and obtains an EXCLUSIVE
+** lock on the database file before attempting to roll it back. See function
+** PagerSharedLock() for more detail.
+**
+** Pager.eLock may only be set to UNKNOWN_LOCK when the pager is in
+** PAGER_OPEN state.
+*/
+#define UNKNOWN_LOCK (EXCLUSIVE_LOCK+1)
+
+/*
+** A macro used for invoking the codec if there is one
+*/
+#ifdef SQLITE_HAS_CODEC
+# define CODEC1(P,D,N,X,E) \
+ if( P->xCodec && P->xCodec(P->pCodec,D,N,X)==0 ){ E; }
+# define CODEC2(P,D,N,X,E,O) \
+ if( P->xCodec==0 ){ O=(char*)D; }else \
+ if( (O=(char*)(P->xCodec(P->pCodec,D,N,X)))==0 ){ E; }
+#else
+# define CODEC1(P,D,N,X,E) /* NO-OP */
+# define CODEC2(P,D,N,X,E,O) O=(char*)D
+#endif
+
+/*
+** The maximum allowed sector size. 64KiB. If the xSectorsize() method
+** returns a value larger than this, then MAX_SECTOR_SIZE is used instead.
+** This could conceivably cause corruption following a power failure on
+** such a system. This is currently an undocumented limit.
+*/
+#define MAX_SECTOR_SIZE 0x10000
+
+
+/*
+** An instance of the following structure is allocated for each active
+** savepoint and statement transaction in the system. All such structures
+** are stored in the Pager.aSavepoint[] array, which is allocated and
+** resized using sqlite3Realloc().
+**
+** When a savepoint is created, the PagerSavepoint.iHdrOffset field is
+** set to 0. If a journal-header is written into the main journal while
+** the savepoint is active, then iHdrOffset is set to the byte offset
+** immediately following the last journal record written into the main
+** journal before the journal-header. This is required during savepoint
+** rollback (see pagerPlaybackSavepoint()).
+*/
+typedef struct PagerSavepoint PagerSavepoint;
+struct PagerSavepoint {
+ i64 iOffset; /* Starting offset in main journal */
+ i64 iHdrOffset; /* See above */
+ Bitvec *pInSavepoint; /* Set of pages in this savepoint */
+ Pgno nOrig; /* Original number of pages in file */
+ Pgno iSubRec; /* Index of first record in sub-journal */
+#ifndef SQLITE_OMIT_WAL
+ u32 aWalData[WAL_SAVEPOINT_NDATA]; /* WAL savepoint context */
+#endif
+};
+
+/*
+** Bits of the Pager.doNotSpill flag. See further description below.
+*/
+#define SPILLFLAG_OFF 0x01 /* Never spill cache. Set via pragma */
+#define SPILLFLAG_ROLLBACK 0x02 /* Current rolling back, so do not spill */
+#define SPILLFLAG_NOSYNC 0x04 /* Spill is ok, but do not sync */
+
+/*
+** An open page cache is an instance of struct Pager. A description of
+** some of the more important member variables follows:
+**
+** eState
+**
+** The current 'state' of the pager object. See the comment and state
+** diagram above for a description of the pager state.
+**
+** eLock
+**
+** For a real on-disk database, the current lock held on the database file -
+** NO_LOCK, SHARED_LOCK, RESERVED_LOCK or EXCLUSIVE_LOCK.
+**
+** For a temporary or in-memory database (neither of which require any
+** locks), this variable is always set to EXCLUSIVE_LOCK. Since such
+** databases always have Pager.exclusiveMode==1, this tricks the pager
+** logic into thinking that it already has all the locks it will ever
+** need (and no reason to release them).
+**
+** In some (obscure) circumstances, this variable may also be set to
+** UNKNOWN_LOCK. See the comment above the #define of UNKNOWN_LOCK for
+** details.
+**
+** changeCountDone
+**
+** This boolean variable is used to make sure that the change-counter
+** (the 4-byte header field at byte offset 24 of the database file) is
+** not updated more often than necessary.
+**
+** It is set to true when the change-counter field is updated, which
+** can only happen if an exclusive lock is held on the database file.
+** It is cleared (set to false) whenever an exclusive lock is
+** relinquished on the database file. Each time a transaction is committed,
+** The changeCountDone flag is inspected. If it is true, the work of
+** updating the change-counter is omitted for the current transaction.
+**
+** This mechanism means that when running in exclusive mode, a connection
+** need only update the change-counter once, for the first transaction
+** committed.
+**
+** setMaster
+**
+** When PagerCommitPhaseOne() is called to commit a transaction, it may
+** (or may not) specify a master-journal name to be written into the
+** journal file before it is synced to disk.
+**
+** Whether or not a journal file contains a master-journal pointer affects
+** the way in which the journal file is finalized after the transaction is
+** committed or rolled back when running in "journal_mode=PERSIST" mode.
+** If a journal file does not contain a master-journal pointer, it is
+** finalized by overwriting the first journal header with zeroes. If
+** it does contain a master-journal pointer the journal file is finalized
+** by truncating it to zero bytes, just as if the connection were
+** running in "journal_mode=truncate" mode.
+**
+** Journal files that contain master journal pointers cannot be finalized
+** simply by overwriting the first journal-header with zeroes, as the
+** master journal pointer could interfere with hot-journal rollback of any
+** subsequently interrupted transaction that reuses the journal file.
+**
+** The flag is cleared as soon as the journal file is finalized (either
+** by PagerCommitPhaseTwo or PagerRollback). If an IO error prevents the
+** journal file from being successfully finalized, the setMaster flag
+** is cleared anyway (and the pager will move to ERROR state).
+**
+** doNotSpill
+**
+** This variables control the behavior of cache-spills (calls made by
+** the pcache module to the pagerStress() routine to write cached data
+** to the file-system in order to free up memory).
+**
+** When bits SPILLFLAG_OFF or SPILLFLAG_ROLLBACK of doNotSpill are set,
+** writing to the database from pagerStress() is disabled altogether.
+** The SPILLFLAG_ROLLBACK case is done in a very obscure case that
+** comes up during savepoint rollback that requires the pcache module
+** to allocate a new page to prevent the journal file from being written
+** while it is being traversed by code in pager_playback(). The SPILLFLAG_OFF
+** case is a user preference.
+**
+** If the SPILLFLAG_NOSYNC bit is set, writing to the database from
+** pagerStress() is permitted, but syncing the journal file is not.
+** This flag is set by sqlite3PagerWrite() when the file-system sector-size
+** is larger than the database page-size in order to prevent a journal sync
+** from happening in between the journalling of two pages on the same sector.
+**
+** subjInMemory
+**
+** This is a boolean variable. If true, then any required sub-journal
+** is opened as an in-memory journal file. If false, then in-memory
+** sub-journals are only used for in-memory pager files.
+**
+** This variable is updated by the upper layer each time a new
+** write-transaction is opened.
+**
+** dbSize, dbOrigSize, dbFileSize
+**
+** Variable dbSize is set to the number of pages in the database file.
+** It is valid in PAGER_READER and higher states (all states except for
+** OPEN and ERROR).
+**
+** dbSize is set based on the size of the database file, which may be
+** larger than the size of the database (the value stored at offset
+** 28 of the database header by the btree). If the size of the file
+** is not an integer multiple of the page-size, the value stored in
+** dbSize is rounded down (i.e. a 5KB file with 2K page-size has dbSize==2).
+** Except, any file that is greater than 0 bytes in size is considered
+** to have at least one page. (i.e. a 1KB file with 2K page-size leads
+** to dbSize==1).
+**
+** During a write-transaction, if pages with page-numbers greater than
+** dbSize are modified in the cache, dbSize is updated accordingly.
+** Similarly, if the database is truncated using PagerTruncateImage(),
+** dbSize is updated.
+**
+** Variables dbOrigSize and dbFileSize are valid in states
+** PAGER_WRITER_LOCKED and higher. dbOrigSize is a copy of the dbSize
+** variable at the start of the transaction. It is used during rollback,
+** and to determine whether or not pages need to be journalled before
+** being modified.
+**
+** Throughout a write-transaction, dbFileSize contains the size of
+** the file on disk in pages. It is set to a copy of dbSize when the
+** write-transaction is first opened, and updated when VFS calls are made
+** to write or truncate the database file on disk.
+**
+** The only reason the dbFileSize variable is required is to suppress
+** unnecessary calls to xTruncate() after committing a transaction. If,
+** when a transaction is committed, the dbFileSize variable indicates
+** that the database file is larger than the database image (Pager.dbSize),
+** pager_truncate() is called. The pager_truncate() call uses xFilesize()
+** to measure the database file on disk, and then truncates it if required.
+** dbFileSize is not used when rolling back a transaction. In this case
+** pager_truncate() is called unconditionally (which means there may be
+** a call to xFilesize() that is not strictly required). In either case,
+** pager_truncate() may cause the file to become smaller or larger.
+**
+** dbHintSize
+**
+** The dbHintSize variable is used to limit the number of calls made to
+** the VFS xFileControl(FCNTL_SIZE_HINT) method.
+**
+** dbHintSize is set to a copy of the dbSize variable when a
+** write-transaction is opened (at the same time as dbFileSize and
+** dbOrigSize). If the xFileControl(FCNTL_SIZE_HINT) method is called,
+** dbHintSize is increased to the number of pages that correspond to the
+** size-hint passed to the method call. See pager_write_pagelist() for
+** details.
+**
+** errCode
+**
+** The Pager.errCode variable is only ever used in PAGER_ERROR state. It
+** is set to zero in all other states. In PAGER_ERROR state, Pager.errCode
+** is always set to SQLITE_FULL, SQLITE_IOERR or one of the SQLITE_IOERR_XXX
+** sub-codes.
+**
+** syncFlags, walSyncFlags
+**
+** syncFlags is either SQLITE_SYNC_NORMAL (0x02) or SQLITE_SYNC_FULL (0x03).
+** syncFlags is used for rollback mode. walSyncFlags is used for WAL mode
+** and contains the flags used to sync the checkpoint operations in the
+** lower two bits, and sync flags used for transaction commits in the WAL
+** file in bits 0x04 and 0x08. In other words, to get the correct sync flags
+** for checkpoint operations, use (walSyncFlags&0x03) and to get the correct
+** sync flags for transaction commit, use ((walSyncFlags>>2)&0x03). Note
+** that with synchronous=NORMAL in WAL mode, transaction commit is not synced
+** meaning that the 0x04 and 0x08 bits are both zero.
+*/
+struct Pager {
+ sqlite3_vfs *pVfs; /* OS functions to use for IO */
+ u8 exclusiveMode; /* Boolean. True if locking_mode==EXCLUSIVE */
+ u8 journalMode; /* One of the PAGER_JOURNALMODE_* values */
+ u8 useJournal; /* Use a rollback journal on this file */
+ u8 noSync; /* Do not sync the journal if true */
+ u8 fullSync; /* Do extra syncs of the journal for robustness */
+ u8 extraSync; /* sync directory after journal delete */
+ u8 syncFlags; /* SYNC_NORMAL or SYNC_FULL otherwise */
+ u8 walSyncFlags; /* See description above */
+ u8 tempFile; /* zFilename is a temporary or immutable file */
+ u8 noLock; /* Do not lock (except in WAL mode) */
+ u8 readOnly; /* True for a read-only database */
+ u8 memDb; /* True to inhibit all file I/O */
+
+ /**************************************************************************
+ ** The following block contains those class members that change during
+ ** routine operation. Class members not in this block are either fixed
+ ** when the pager is first created or else only change when there is a
+ ** significant mode change (such as changing the page_size, locking_mode,
+ ** or the journal_mode). From another view, these class members describe
+ ** the "state" of the pager, while other class members describe the
+ ** "configuration" of the pager.
+ */
+ u8 eState; /* Pager state (OPEN, READER, WRITER_LOCKED..) */
+ u8 eLock; /* Current lock held on database file */
+ u8 changeCountDone; /* Set after incrementing the change-counter */
+ u8 setMaster; /* True if a m-j name has been written to jrnl */
+ u8 doNotSpill; /* Do not spill the cache when non-zero */
+ u8 subjInMemory; /* True to use in-memory sub-journals */
+ u8 bUseFetch; /* True to use xFetch() */
+ u8 hasHeldSharedLock; /* True if a shared lock has ever been held */
+ Pgno dbSize; /* Number of pages in the database */
+ Pgno dbOrigSize; /* dbSize before the current transaction */
+ Pgno dbFileSize; /* Number of pages in the database file */
+ Pgno dbHintSize; /* Value passed to FCNTL_SIZE_HINT call */
+ int errCode; /* One of several kinds of errors */
+ int nRec; /* Pages journalled since last j-header written */
+ u32 cksumInit; /* Quasi-random value added to every checksum */
+ u32 nSubRec; /* Number of records written to sub-journal */
+ Bitvec *pInJournal; /* One bit for each page in the database file */
+ sqlite3_file *fd; /* File descriptor for database */
+ sqlite3_file *jfd; /* File descriptor for main journal */
+ sqlite3_file *sjfd; /* File descriptor for sub-journal */
+ i64 journalOff; /* Current write offset in the journal file */
+ i64 journalHdr; /* Byte offset to previous journal header */
+ sqlite3_backup *pBackup; /* Pointer to list of ongoing backup processes */
+ PagerSavepoint *aSavepoint; /* Array of active savepoints */
+ int nSavepoint; /* Number of elements in aSavepoint[] */
+ u32 iDataVersion; /* Changes whenever database content changes */
+ char dbFileVers[16]; /* Changes whenever database file changes */
+
+ int nMmapOut; /* Number of mmap pages currently outstanding */
+ sqlite3_int64 szMmap; /* Desired maximum mmap size */
+ PgHdr *pMmapFreelist; /* List of free mmap page headers (pDirty) */
+ /*
+ ** End of the routinely-changing class members
+ ***************************************************************************/
+
+ u16 nExtra; /* Add this many bytes to each in-memory page */
+ i16 nReserve; /* Number of unused bytes at end of each page */
+ u32 vfsFlags; /* Flags for sqlite3_vfs.xOpen() */
+ u32 sectorSize; /* Assumed sector size during rollback */
+ int pageSize; /* Number of bytes in a page */
+ Pgno mxPgno; /* Maximum allowed size of the database */
+ i64 journalSizeLimit; /* Size limit for persistent journal files */
+ char *zFilename; /* Name of the database file */
+ char *zJournal; /* Name of the journal file */
+ int (*xBusyHandler)(void*); /* Function to call when busy */
+ void *pBusyHandlerArg; /* Context argument for xBusyHandler */
+ int aStat[4]; /* Total cache hits, misses, writes, spills */
+#ifdef SQLITE_TEST
+ int nRead; /* Database pages read */
+#endif
+ void (*xReiniter)(DbPage*); /* Call this routine when reloading pages */
+ int (*xGet)(Pager*,Pgno,DbPage**,int); /* Routine to fetch a patch */
+#ifdef SQLITE_HAS_CODEC
+ void *(*xCodec)(void*,void*,Pgno,int); /* Routine for en/decoding data */
+ void (*xCodecSizeChng)(void*,int,int); /* Notify of page size changes */
+ void (*xCodecFree)(void*); /* Destructor for the codec */
+ void *pCodec; /* First argument to xCodec... methods */
+#endif
+ char *pTmpSpace; /* Pager.pageSize bytes of space for tmp use */
+ PCache *pPCache; /* Pointer to page cache object */
+#ifndef SQLITE_OMIT_WAL
+ Wal *pWal; /* Write-ahead log used by "journal_mode=wal" */
+ char *zWal; /* File name for write-ahead log */
+#endif
+};
+
+/*
+** Indexes for use with Pager.aStat[]. The Pager.aStat[] array contains
+** the values accessed by passing SQLITE_DBSTATUS_CACHE_HIT, CACHE_MISS
+** or CACHE_WRITE to sqlite3_db_status().
+*/
+#define PAGER_STAT_HIT 0
+#define PAGER_STAT_MISS 1
+#define PAGER_STAT_WRITE 2
+#define PAGER_STAT_SPILL 3
+
+/*
+** The following global variables hold counters used for
+** testing purposes only. These variables do not exist in
+** a non-testing build. These variables are not thread-safe.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_pager_readdb_count = 0; /* Number of full pages read from DB */
+SQLITE_API int sqlite3_pager_writedb_count = 0; /* Number of full pages written to DB */
+SQLITE_API int sqlite3_pager_writej_count = 0; /* Number of pages written to journal */
+# define PAGER_INCR(v) v++
+#else
+# define PAGER_INCR(v)
+#endif
+
+
+
+/*
+** Journal files begin with the following magic string. The data
+** was obtained from /dev/random. It is used only as a sanity check.
+**
+** Since version 2.8.0, the journal format contains additional sanity
+** checking information. If the power fails while the journal is being
+** written, semi-random garbage data might appear in the journal
+** file after power is restored. If an attempt is then made
+** to roll the journal back, the database could be corrupted. The additional
+** sanity checking data is an attempt to discover the garbage in the
+** journal and ignore it.
+**
+** The sanity checking information for the new journal format consists
+** of a 32-bit checksum on each page of data. The checksum covers both
+** the page number and the pPager->pageSize bytes of data for the page.
+** This cksum is initialized to a 32-bit random value that appears in the
+** journal file right after the header. The random initializer is important,
+** because garbage data that appears at the end of a journal is likely
+** data that was once in other files that have now been deleted. If the
+** garbage data came from an obsolete journal file, the checksums might
+** be correct. But by initializing the checksum to random value which
+** is different for every journal, we minimize that risk.
+*/
+static const unsigned char aJournalMagic[] = {
+ 0xd9, 0xd5, 0x05, 0xf9, 0x20, 0xa1, 0x63, 0xd7,
+};
+
+/*
+** The size of the of each page record in the journal is given by
+** the following macro.
+*/
+#define JOURNAL_PG_SZ(pPager) ((pPager->pageSize) + 8)
+
+/*
+** The journal header size for this pager. This is usually the same
+** size as a single disk sector. See also setSectorSize().
+*/
+#define JOURNAL_HDR_SZ(pPager) (pPager->sectorSize)
+
+/*
+** The macro MEMDB is true if we are dealing with an in-memory database.
+** We do this as a macro so that if the SQLITE_OMIT_MEMORYDB macro is set,
+** the value of MEMDB will be a constant and the compiler will optimize
+** out code that would never execute.
+*/
+#ifdef SQLITE_OMIT_MEMORYDB
+# define MEMDB 0
+#else
+# define MEMDB pPager->memDb
+#endif
+
+/*
+** The macro USEFETCH is true if we are allowed to use the xFetch and xUnfetch
+** interfaces to access the database using memory-mapped I/O.
+*/
+#if SQLITE_MAX_MMAP_SIZE>0
+# define USEFETCH(x) ((x)->bUseFetch)
+#else
+# define USEFETCH(x) 0
+#endif
+
+/*
+** The maximum legal page number is (2^31 - 1).
+*/
+#define PAGER_MAX_PGNO 2147483647
+
+/*
+** The argument to this macro is a file descriptor (type sqlite3_file*).
+** Return 0 if it is not open, or non-zero (but not 1) if it is.
+**
+** This is so that expressions can be written as:
+**
+** if( isOpen(pPager->jfd) ){ ...
+**
+** instead of
+**
+** if( pPager->jfd->pMethods ){ ...
+*/
+#define isOpen(pFd) ((pFd)->pMethods!=0)
+
+/*
+** Return true if this pager uses a write-ahead log to read page pgno.
+** Return false if the pager reads pgno directly from the database.
+*/
+#if !defined(SQLITE_OMIT_WAL) && defined(SQLITE_DIRECT_OVERFLOW_READ)
+SQLITE_PRIVATE int sqlite3PagerUseWal(Pager *pPager, Pgno pgno){
+ u32 iRead = 0;
+ int rc;
+ if( pPager->pWal==0 ) return 0;
+ rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iRead);
+ return rc || iRead;
+}
+#endif
+#ifndef SQLITE_OMIT_WAL
+# define pagerUseWal(x) ((x)->pWal!=0)
+#else
+# define pagerUseWal(x) 0
+# define pagerRollbackWal(x) 0
+# define pagerWalFrames(v,w,x,y) 0
+# define pagerOpenWalIfPresent(z) SQLITE_OK
+# define pagerBeginReadTransaction(z) SQLITE_OK
+#endif
+
+#ifndef NDEBUG
+/*
+** Usage:
+**
+** assert( assert_pager_state(pPager) );
+**
+** This function runs many asserts to try to find inconsistencies in
+** the internal state of the Pager object.
+*/
+static int assert_pager_state(Pager *p){
+ Pager *pPager = p;
+
+ /* State must be valid. */
+ assert( p->eState==PAGER_OPEN
+ || p->eState==PAGER_READER
+ || p->eState==PAGER_WRITER_LOCKED
+ || p->eState==PAGER_WRITER_CACHEMOD
+ || p->eState==PAGER_WRITER_DBMOD
+ || p->eState==PAGER_WRITER_FINISHED
+ || p->eState==PAGER_ERROR
+ );
+
+ /* Regardless of the current state, a temp-file connection always behaves
+ ** as if it has an exclusive lock on the database file. It never updates
+ ** the change-counter field, so the changeCountDone flag is always set.
+ */
+ assert( p->tempFile==0 || p->eLock==EXCLUSIVE_LOCK );
+ assert( p->tempFile==0 || pPager->changeCountDone );
+
+ /* If the useJournal flag is clear, the journal-mode must be "OFF".
+ ** And if the journal-mode is "OFF", the journal file must not be open.
+ */
+ assert( p->journalMode==PAGER_JOURNALMODE_OFF || p->useJournal );
+ assert( p->journalMode!=PAGER_JOURNALMODE_OFF || !isOpen(p->jfd) );
+
+ /* Check that MEMDB implies noSync. And an in-memory journal. Since
+ ** this means an in-memory pager performs no IO at all, it cannot encounter
+ ** either SQLITE_IOERR or SQLITE_FULL during rollback or while finalizing
+ ** a journal file. (although the in-memory journal implementation may
+ ** return SQLITE_IOERR_NOMEM while the journal file is being written). It
+ ** is therefore not possible for an in-memory pager to enter the ERROR
+ ** state.
+ */
+ if( MEMDB ){
+ assert( !isOpen(p->fd) );
+ assert( p->noSync );
+ assert( p->journalMode==PAGER_JOURNALMODE_OFF
+ || p->journalMode==PAGER_JOURNALMODE_MEMORY
+ );
+ assert( p->eState!=PAGER_ERROR && p->eState!=PAGER_OPEN );
+ assert( pagerUseWal(p)==0 );
+ }
+
+ /* If changeCountDone is set, a RESERVED lock or greater must be held
+ ** on the file.
+ */
+ assert( pPager->changeCountDone==0 || pPager->eLock>=RESERVED_LOCK );
+ assert( p->eLock!=PENDING_LOCK );
+
+ switch( p->eState ){
+ case PAGER_OPEN:
+ assert( !MEMDB );
+ assert( pPager->errCode==SQLITE_OK );
+ assert( sqlite3PcacheRefCount(pPager->pPCache)==0 || pPager->tempFile );
+ break;
+
+ case PAGER_READER:
+ assert( pPager->errCode==SQLITE_OK );
+ assert( p->eLock!=UNKNOWN_LOCK );
+ assert( p->eLock>=SHARED_LOCK );
+ break;
+
+ case PAGER_WRITER_LOCKED:
+ assert( p->eLock!=UNKNOWN_LOCK );
+ assert( pPager->errCode==SQLITE_OK );
+ if( !pagerUseWal(pPager) ){
+ assert( p->eLock>=RESERVED_LOCK );
+ }
+ assert( pPager->dbSize==pPager->dbOrigSize );
+ assert( pPager->dbOrigSize==pPager->dbFileSize );
+ assert( pPager->dbOrigSize==pPager->dbHintSize );
+ assert( pPager->setMaster==0 );
+ break;
+
+ case PAGER_WRITER_CACHEMOD:
+ assert( p->eLock!=UNKNOWN_LOCK );
+ assert( pPager->errCode==SQLITE_OK );
+ if( !pagerUseWal(pPager) ){
+ /* It is possible that if journal_mode=wal here that neither the
+ ** journal file nor the WAL file are open. This happens during
+ ** a rollback transaction that switches from journal_mode=off
+ ** to journal_mode=wal.
+ */
+ assert( p->eLock>=RESERVED_LOCK );
+ assert( isOpen(p->jfd)
+ || p->journalMode==PAGER_JOURNALMODE_OFF
+ || p->journalMode==PAGER_JOURNALMODE_WAL
+ );
+ }
+ assert( pPager->dbOrigSize==pPager->dbFileSize );
+ assert( pPager->dbOrigSize==pPager->dbHintSize );
+ break;
+
+ case PAGER_WRITER_DBMOD:
+ assert( p->eLock==EXCLUSIVE_LOCK );
+ assert( pPager->errCode==SQLITE_OK );
+ assert( !pagerUseWal(pPager) );
+ assert( p->eLock>=EXCLUSIVE_LOCK );
+ assert( isOpen(p->jfd)
+ || p->journalMode==PAGER_JOURNALMODE_OFF
+ || p->journalMode==PAGER_JOURNALMODE_WAL
+ || (sqlite3OsDeviceCharacteristics(p->fd)&SQLITE_IOCAP_BATCH_ATOMIC)
+ );
+ assert( pPager->dbOrigSize<=pPager->dbHintSize );
+ break;
+
+ case PAGER_WRITER_FINISHED:
+ assert( p->eLock==EXCLUSIVE_LOCK );
+ assert( pPager->errCode==SQLITE_OK );
+ assert( !pagerUseWal(pPager) );
+ assert( isOpen(p->jfd)
+ || p->journalMode==PAGER_JOURNALMODE_OFF
+ || p->journalMode==PAGER_JOURNALMODE_WAL
+ || (sqlite3OsDeviceCharacteristics(p->fd)&SQLITE_IOCAP_BATCH_ATOMIC)
+ );
+ break;
+
+ case PAGER_ERROR:
+ /* There must be at least one outstanding reference to the pager if
+ ** in ERROR state. Otherwise the pager should have already dropped
+ ** back to OPEN state.
+ */
+ assert( pPager->errCode!=SQLITE_OK );
+ assert( sqlite3PcacheRefCount(pPager->pPCache)>0 || pPager->tempFile );
+ break;
+ }
+
+ return 1;
+}
+#endif /* ifndef NDEBUG */
+
+#ifdef SQLITE_DEBUG
+/*
+** Return a pointer to a human readable string in a static buffer
+** containing the state of the Pager object passed as an argument. This
+** is intended to be used within debuggers. For example, as an alternative
+** to "print *pPager" in gdb:
+**
+** (gdb) printf "%s", print_pager_state(pPager)
+**
+** This routine has external linkage in order to suppress compiler warnings
+** about an unused function. It is enclosed within SQLITE_DEBUG and so does
+** not appear in normal builds.
+*/
+char *print_pager_state(Pager *p){
+ static char zRet[1024];
+
+ sqlite3_snprintf(1024, zRet,
+ "Filename: %s\n"
+ "State: %s errCode=%d\n"
+ "Lock: %s\n"
+ "Locking mode: locking_mode=%s\n"
+ "Journal mode: journal_mode=%s\n"
+ "Backing store: tempFile=%d memDb=%d useJournal=%d\n"
+ "Journal: journalOff=%lld journalHdr=%lld\n"
+ "Size: dbsize=%d dbOrigSize=%d dbFileSize=%d\n"
+ , p->zFilename
+ , p->eState==PAGER_OPEN ? "OPEN" :
+ p->eState==PAGER_READER ? "READER" :
+ p->eState==PAGER_WRITER_LOCKED ? "WRITER_LOCKED" :
+ p->eState==PAGER_WRITER_CACHEMOD ? "WRITER_CACHEMOD" :
+ p->eState==PAGER_WRITER_DBMOD ? "WRITER_DBMOD" :
+ p->eState==PAGER_WRITER_FINISHED ? "WRITER_FINISHED" :
+ p->eState==PAGER_ERROR ? "ERROR" : "?error?"
+ , (int)p->errCode
+ , p->eLock==NO_LOCK ? "NO_LOCK" :
+ p->eLock==RESERVED_LOCK ? "RESERVED" :
+ p->eLock==EXCLUSIVE_LOCK ? "EXCLUSIVE" :
+ p->eLock==SHARED_LOCK ? "SHARED" :
+ p->eLock==UNKNOWN_LOCK ? "UNKNOWN" : "?error?"
+ , p->exclusiveMode ? "exclusive" : "normal"
+ , p->journalMode==PAGER_JOURNALMODE_MEMORY ? "memory" :
+ p->journalMode==PAGER_JOURNALMODE_OFF ? "off" :
+ p->journalMode==PAGER_JOURNALMODE_DELETE ? "delete" :
+ p->journalMode==PAGER_JOURNALMODE_PERSIST ? "persist" :
+ p->journalMode==PAGER_JOURNALMODE_TRUNCATE ? "truncate" :
+ p->journalMode==PAGER_JOURNALMODE_WAL ? "wal" : "?error?"
+ , (int)p->tempFile, (int)p->memDb, (int)p->useJournal
+ , p->journalOff, p->journalHdr
+ , (int)p->dbSize, (int)p->dbOrigSize, (int)p->dbFileSize
+ );
+
+ return zRet;
+}
+#endif
+
+/* Forward references to the various page getters */
+static int getPageNormal(Pager*,Pgno,DbPage**,int);
+static int getPageError(Pager*,Pgno,DbPage**,int);
+#if SQLITE_MAX_MMAP_SIZE>0
+static int getPageMMap(Pager*,Pgno,DbPage**,int);
+#endif
+
+/*
+** Set the Pager.xGet method for the appropriate routine used to fetch
+** content from the pager.
+*/
+static void setGetterMethod(Pager *pPager){
+ if( pPager->errCode ){
+ pPager->xGet = getPageError;
+#if SQLITE_MAX_MMAP_SIZE>0
+ }else if( USEFETCH(pPager)
+#ifdef SQLITE_HAS_CODEC
+ && pPager->xCodec==0
+#endif
+ ){
+ pPager->xGet = getPageMMap;
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
+ }else{
+ pPager->xGet = getPageNormal;
+ }
+}
+
+/*
+** Return true if it is necessary to write page *pPg into the sub-journal.
+** A page needs to be written into the sub-journal if there exists one
+** or more open savepoints for which:
+**
+** * The page-number is less than or equal to PagerSavepoint.nOrig, and
+** * The bit corresponding to the page-number is not set in
+** PagerSavepoint.pInSavepoint.
+*/
+static int subjRequiresPage(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ PagerSavepoint *p;
+ Pgno pgno = pPg->pgno;
+ int i;
+ for(i=0; inSavepoint; i++){
+ p = &pPager->aSavepoint[i];
+ if( p->nOrig>=pgno && 0==sqlite3BitvecTestNotNull(p->pInSavepoint, pgno) ){
+ return 1;
+ }
+ }
+ return 0;
+}
+
+#ifdef SQLITE_DEBUG
+/*
+** Return true if the page is already in the journal file.
+*/
+static int pageInJournal(Pager *pPager, PgHdr *pPg){
+ return sqlite3BitvecTest(pPager->pInJournal, pPg->pgno);
+}
+#endif
+
+/*
+** Read a 32-bit integer from the given file descriptor. Store the integer
+** that is read in *pRes. Return SQLITE_OK if everything worked, or an
+** error code is something goes wrong.
+**
+** All values are stored on disk as big-endian.
+*/
+static int read32bits(sqlite3_file *fd, i64 offset, u32 *pRes){
+ unsigned char ac[4];
+ int rc = sqlite3OsRead(fd, ac, sizeof(ac), offset);
+ if( rc==SQLITE_OK ){
+ *pRes = sqlite3Get4byte(ac);
+ }
+ return rc;
+}
+
+/*
+** Write a 32-bit integer into a string buffer in big-endian byte order.
+*/
+#define put32bits(A,B) sqlite3Put4byte((u8*)A,B)
+
+
+/*
+** Write a 32-bit integer into the given file descriptor. Return SQLITE_OK
+** on success or an error code is something goes wrong.
+*/
+static int write32bits(sqlite3_file *fd, i64 offset, u32 val){
+ char ac[4];
+ put32bits(ac, val);
+ return sqlite3OsWrite(fd, ac, 4, offset);
+}
+
+/*
+** Unlock the database file to level eLock, which must be either NO_LOCK
+** or SHARED_LOCK. Regardless of whether or not the call to xUnlock()
+** succeeds, set the Pager.eLock variable to match the (attempted) new lock.
+**
+** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is
+** called, do not modify it. See the comment above the #define of
+** UNKNOWN_LOCK for an explanation of this.
+*/
+static int pagerUnlockDb(Pager *pPager, int eLock){
+ int rc = SQLITE_OK;
+
+ assert( !pPager->exclusiveMode || pPager->eLock==eLock );
+ assert( eLock==NO_LOCK || eLock==SHARED_LOCK );
+ assert( eLock!=NO_LOCK || pagerUseWal(pPager)==0 );
+ if( isOpen(pPager->fd) ){
+ assert( pPager->eLock>=eLock );
+ rc = pPager->noLock ? SQLITE_OK : sqlite3OsUnlock(pPager->fd, eLock);
+ if( pPager->eLock!=UNKNOWN_LOCK ){
+ pPager->eLock = (u8)eLock;
+ }
+ IOTRACE(("UNLOCK %p %d\n", pPager, eLock))
+ }
+ return rc;
+}
+
+/*
+** Lock the database file to level eLock, which must be either SHARED_LOCK,
+** RESERVED_LOCK or EXCLUSIVE_LOCK. If the caller is successful, set the
+** Pager.eLock variable to the new locking state.
+**
+** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is
+** called, do not modify it unless the new locking state is EXCLUSIVE_LOCK.
+** See the comment above the #define of UNKNOWN_LOCK for an explanation
+** of this.
+*/
+static int pagerLockDb(Pager *pPager, int eLock){
+ int rc = SQLITE_OK;
+
+ assert( eLock==SHARED_LOCK || eLock==RESERVED_LOCK || eLock==EXCLUSIVE_LOCK );
+ if( pPager->eLockeLock==UNKNOWN_LOCK ){
+ rc = pPager->noLock ? SQLITE_OK : sqlite3OsLock(pPager->fd, eLock);
+ if( rc==SQLITE_OK && (pPager->eLock!=UNKNOWN_LOCK||eLock==EXCLUSIVE_LOCK) ){
+ pPager->eLock = (u8)eLock;
+ IOTRACE(("LOCK %p %d\n", pPager, eLock))
+ }
+ }
+ return rc;
+}
+
+/*
+** This function determines whether or not the atomic-write or
+** atomic-batch-write optimizations can be used with this pager. The
+** atomic-write optimization can be used if:
+**
+** (a) the value returned by OsDeviceCharacteristics() indicates that
+** a database page may be written atomically, and
+** (b) the value returned by OsSectorSize() is less than or equal
+** to the page size.
+**
+** If it can be used, then the value returned is the size of the journal
+** file when it contains rollback data for exactly one page.
+**
+** The atomic-batch-write optimization can be used if OsDeviceCharacteristics()
+** returns a value with the SQLITE_IOCAP_BATCH_ATOMIC bit set. -1 is
+** returned in this case.
+**
+** If neither optimization can be used, 0 is returned.
+*/
+static int jrnlBufferSize(Pager *pPager){
+ assert( !MEMDB );
+
+#if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
+ || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
+ int dc; /* Device characteristics */
+
+ assert( isOpen(pPager->fd) );
+ dc = sqlite3OsDeviceCharacteristics(pPager->fd);
+#else
+ UNUSED_PARAMETER(pPager);
+#endif
+
+#ifdef SQLITE_ENABLE_BATCH_ATOMIC_WRITE
+ if( pPager->dbSize>0 && (dc&SQLITE_IOCAP_BATCH_ATOMIC) ){
+ return -1;
+ }
+#endif
+
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+ {
+ int nSector = pPager->sectorSize;
+ int szPage = pPager->pageSize;
+
+ assert(SQLITE_IOCAP_ATOMIC512==(512>>8));
+ assert(SQLITE_IOCAP_ATOMIC64K==(65536>>8));
+ if( 0==(dc&(SQLITE_IOCAP_ATOMIC|(szPage>>8)) || nSector>szPage) ){
+ return 0;
+ }
+ }
+
+ return JOURNAL_HDR_SZ(pPager) + JOURNAL_PG_SZ(pPager);
+#endif
+
+ return 0;
+}
+
+/*
+** If SQLITE_CHECK_PAGES is defined then we do some sanity checking
+** on the cache using a hash function. This is used for testing
+** and debugging only.
+*/
+#ifdef SQLITE_CHECK_PAGES
+/*
+** Return a 32-bit hash of the page data for pPage.
+*/
+static u32 pager_datahash(int nByte, unsigned char *pData){
+ u32 hash = 0;
+ int i;
+ for(i=0; ipPager->pageSize, (unsigned char *)pPage->pData);
+}
+static void pager_set_pagehash(PgHdr *pPage){
+ pPage->pageHash = pager_pagehash(pPage);
+}
+
+/*
+** The CHECK_PAGE macro takes a PgHdr* as an argument. If SQLITE_CHECK_PAGES
+** is defined, and NDEBUG is not defined, an assert() statement checks
+** that the page is either dirty or still matches the calculated page-hash.
+*/
+#define CHECK_PAGE(x) checkPage(x)
+static void checkPage(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ assert( pPager->eState!=PAGER_ERROR );
+ assert( (pPg->flags&PGHDR_DIRTY) || pPg->pageHash==pager_pagehash(pPg) );
+}
+
+#else
+#define pager_datahash(X,Y) 0
+#define pager_pagehash(X) 0
+#define pager_set_pagehash(X)
+#define CHECK_PAGE(x)
+#endif /* SQLITE_CHECK_PAGES */
+
+/*
+** When this is called the journal file for pager pPager must be open.
+** This function attempts to read a master journal file name from the
+** end of the file and, if successful, copies it into memory supplied
+** by the caller. See comments above writeMasterJournal() for the format
+** used to store a master journal file name at the end of a journal file.
+**
+** zMaster must point to a buffer of at least nMaster bytes allocated by
+** the caller. This should be sqlite3_vfs.mxPathname+1 (to ensure there is
+** enough space to write the master journal name). If the master journal
+** name in the journal is longer than nMaster bytes (including a
+** nul-terminator), then this is handled as if no master journal name
+** were present in the journal.
+**
+** If a master journal file name is present at the end of the journal
+** file, then it is copied into the buffer pointed to by zMaster. A
+** nul-terminator byte is appended to the buffer following the master
+** journal file name.
+**
+** If it is determined that no master journal file name is present
+** zMaster[0] is set to 0 and SQLITE_OK returned.
+**
+** If an error occurs while reading from the journal file, an SQLite
+** error code is returned.
+*/
+static int readMasterJournal(sqlite3_file *pJrnl, char *zMaster, u32 nMaster){
+ int rc; /* Return code */
+ u32 len; /* Length in bytes of master journal name */
+ i64 szJ; /* Total size in bytes of journal file pJrnl */
+ u32 cksum; /* MJ checksum value read from journal */
+ u32 u; /* Unsigned loop counter */
+ unsigned char aMagic[8]; /* A buffer to hold the magic header */
+ zMaster[0] = '\0';
+
+ if( SQLITE_OK!=(rc = sqlite3OsFileSize(pJrnl, &szJ))
+ || szJ<16
+ || SQLITE_OK!=(rc = read32bits(pJrnl, szJ-16, &len))
+ || len>=nMaster
+ || len>szJ-16
+ || len==0
+ || SQLITE_OK!=(rc = read32bits(pJrnl, szJ-12, &cksum))
+ || SQLITE_OK!=(rc = sqlite3OsRead(pJrnl, aMagic, 8, szJ-8))
+ || memcmp(aMagic, aJournalMagic, 8)
+ || SQLITE_OK!=(rc = sqlite3OsRead(pJrnl, zMaster, len, szJ-16-len))
+ ){
+ return rc;
+ }
+
+ /* See if the checksum matches the master journal name */
+ for(u=0; ujournalOff, assuming a sector
+** size of pPager->sectorSize bytes.
+**
+** i.e for a sector size of 512:
+**
+** Pager.journalOff Return value
+** ---------------------------------------
+** 0 0
+** 512 512
+** 100 512
+** 2000 2048
+**
+*/
+static i64 journalHdrOffset(Pager *pPager){
+ i64 offset = 0;
+ i64 c = pPager->journalOff;
+ if( c ){
+ offset = ((c-1)/JOURNAL_HDR_SZ(pPager) + 1) * JOURNAL_HDR_SZ(pPager);
+ }
+ assert( offset%JOURNAL_HDR_SZ(pPager)==0 );
+ assert( offset>=c );
+ assert( (offset-c)jfd) );
+ assert( !sqlite3JournalIsInMemory(pPager->jfd) );
+ if( pPager->journalOff ){
+ const i64 iLimit = pPager->journalSizeLimit; /* Local cache of jsl */
+
+ IOTRACE(("JZEROHDR %p\n", pPager))
+ if( doTruncate || iLimit==0 ){
+ rc = sqlite3OsTruncate(pPager->jfd, 0);
+ }else{
+ static const char zeroHdr[28] = {0};
+ rc = sqlite3OsWrite(pPager->jfd, zeroHdr, sizeof(zeroHdr), 0);
+ }
+ if( rc==SQLITE_OK && !pPager->noSync ){
+ rc = sqlite3OsSync(pPager->jfd, SQLITE_SYNC_DATAONLY|pPager->syncFlags);
+ }
+
+ /* At this point the transaction is committed but the write lock
+ ** is still held on the file. If there is a size limit configured for
+ ** the persistent journal and the journal file currently consumes more
+ ** space than that limit allows for, truncate it now. There is no need
+ ** to sync the file following this operation.
+ */
+ if( rc==SQLITE_OK && iLimit>0 ){
+ i64 sz;
+ rc = sqlite3OsFileSize(pPager->jfd, &sz);
+ if( rc==SQLITE_OK && sz>iLimit ){
+ rc = sqlite3OsTruncate(pPager->jfd, iLimit);
+ }
+ }
+ }
+ return rc;
+}
+
+/*
+** The journal file must be open when this routine is called. A journal
+** header (JOURNAL_HDR_SZ bytes) is written into the journal file at the
+** current location.
+**
+** The format for the journal header is as follows:
+** - 8 bytes: Magic identifying journal format.
+** - 4 bytes: Number of records in journal, or -1 no-sync mode is on.
+** - 4 bytes: Random number used for page hash.
+** - 4 bytes: Initial database page count.
+** - 4 bytes: Sector size used by the process that wrote this journal.
+** - 4 bytes: Database page size.
+**
+** Followed by (JOURNAL_HDR_SZ - 28) bytes of unused space.
+*/
+static int writeJournalHdr(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+ char *zHeader = pPager->pTmpSpace; /* Temporary space used to build header */
+ u32 nHeader = (u32)pPager->pageSize;/* Size of buffer pointed to by zHeader */
+ u32 nWrite; /* Bytes of header sector written */
+ int ii; /* Loop counter */
+
+ assert( isOpen(pPager->jfd) ); /* Journal file must be open. */
+
+ if( nHeader>JOURNAL_HDR_SZ(pPager) ){
+ nHeader = JOURNAL_HDR_SZ(pPager);
+ }
+
+ /* If there are active savepoints and any of them were created
+ ** since the most recent journal header was written, update the
+ ** PagerSavepoint.iHdrOffset fields now.
+ */
+ for(ii=0; iinSavepoint; ii++){
+ if( pPager->aSavepoint[ii].iHdrOffset==0 ){
+ pPager->aSavepoint[ii].iHdrOffset = pPager->journalOff;
+ }
+ }
+
+ pPager->journalHdr = pPager->journalOff = journalHdrOffset(pPager);
+
+ /*
+ ** Write the nRec Field - the number of page records that follow this
+ ** journal header. Normally, zero is written to this value at this time.
+ ** After the records are added to the journal (and the journal synced,
+ ** if in full-sync mode), the zero is overwritten with the true number
+ ** of records (see syncJournal()).
+ **
+ ** A faster alternative is to write 0xFFFFFFFF to the nRec field. When
+ ** reading the journal this value tells SQLite to assume that the
+ ** rest of the journal file contains valid page records. This assumption
+ ** is dangerous, as if a failure occurred whilst writing to the journal
+ ** file it may contain some garbage data. There are two scenarios
+ ** where this risk can be ignored:
+ **
+ ** * When the pager is in no-sync mode. Corruption can follow a
+ ** power failure in this case anyway.
+ **
+ ** * When the SQLITE_IOCAP_SAFE_APPEND flag is set. This guarantees
+ ** that garbage data is never appended to the journal file.
+ */
+ assert( isOpen(pPager->fd) || pPager->noSync );
+ if( pPager->noSync || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
+ || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND)
+ ){
+ memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
+ put32bits(&zHeader[sizeof(aJournalMagic)], 0xffffffff);
+ }else{
+ memset(zHeader, 0, sizeof(aJournalMagic)+4);
+ }
+
+ /* The random check-hash initializer */
+ sqlite3_randomness(sizeof(pPager->cksumInit), &pPager->cksumInit);
+ put32bits(&zHeader[sizeof(aJournalMagic)+4], pPager->cksumInit);
+ /* The initial database size */
+ put32bits(&zHeader[sizeof(aJournalMagic)+8], pPager->dbOrigSize);
+ /* The assumed sector size for this process */
+ put32bits(&zHeader[sizeof(aJournalMagic)+12], pPager->sectorSize);
+
+ /* The page size */
+ put32bits(&zHeader[sizeof(aJournalMagic)+16], pPager->pageSize);
+
+ /* Initializing the tail of the buffer is not necessary. Everything
+ ** works find if the following memset() is omitted. But initializing
+ ** the memory prevents valgrind from complaining, so we are willing to
+ ** take the performance hit.
+ */
+ memset(&zHeader[sizeof(aJournalMagic)+20], 0,
+ nHeader-(sizeof(aJournalMagic)+20));
+
+ /* In theory, it is only necessary to write the 28 bytes that the
+ ** journal header consumes to the journal file here. Then increment the
+ ** Pager.journalOff variable by JOURNAL_HDR_SZ so that the next
+ ** record is written to the following sector (leaving a gap in the file
+ ** that will be implicitly filled in by the OS).
+ **
+ ** However it has been discovered that on some systems this pattern can
+ ** be significantly slower than contiguously writing data to the file,
+ ** even if that means explicitly writing data to the block of
+ ** (JOURNAL_HDR_SZ - 28) bytes that will not be used. So that is what
+ ** is done.
+ **
+ ** The loop is required here in case the sector-size is larger than the
+ ** database page size. Since the zHeader buffer is only Pager.pageSize
+ ** bytes in size, more than one call to sqlite3OsWrite() may be required
+ ** to populate the entire journal header sector.
+ */
+ for(nWrite=0; rc==SQLITE_OK&&nWritejournalHdr, nHeader))
+ rc = sqlite3OsWrite(pPager->jfd, zHeader, nHeader, pPager->journalOff);
+ assert( pPager->journalHdr <= pPager->journalOff );
+ pPager->journalOff += nHeader;
+ }
+
+ return rc;
+}
+
+/*
+** The journal file must be open when this is called. A journal header file
+** (JOURNAL_HDR_SZ bytes) is read from the current location in the journal
+** file. The current location in the journal file is given by
+** pPager->journalOff. See comments above function writeJournalHdr() for
+** a description of the journal header format.
+**
+** If the header is read successfully, *pNRec is set to the number of
+** page records following this header and *pDbSize is set to the size of the
+** database before the transaction began, in pages. Also, pPager->cksumInit
+** is set to the value read from the journal header. SQLITE_OK is returned
+** in this case.
+**
+** If the journal header file appears to be corrupted, SQLITE_DONE is
+** returned and *pNRec and *PDbSize are undefined. If JOURNAL_HDR_SZ bytes
+** cannot be read from the journal file an error code is returned.
+*/
+static int readJournalHdr(
+ Pager *pPager, /* Pager object */
+ int isHot,
+ i64 journalSize, /* Size of the open journal file in bytes */
+ u32 *pNRec, /* OUT: Value read from the nRec field */
+ u32 *pDbSize /* OUT: Value of original database size field */
+){
+ int rc; /* Return code */
+ unsigned char aMagic[8]; /* A buffer to hold the magic header */
+ i64 iHdrOff; /* Offset of journal header being read */
+
+ assert( isOpen(pPager->jfd) ); /* Journal file must be open. */
+
+ /* Advance Pager.journalOff to the start of the next sector. If the
+ ** journal file is too small for there to be a header stored at this
+ ** point, return SQLITE_DONE.
+ */
+ pPager->journalOff = journalHdrOffset(pPager);
+ if( pPager->journalOff+JOURNAL_HDR_SZ(pPager) > journalSize ){
+ return SQLITE_DONE;
+ }
+ iHdrOff = pPager->journalOff;
+
+ /* Read in the first 8 bytes of the journal header. If they do not match
+ ** the magic string found at the start of each journal header, return
+ ** SQLITE_DONE. If an IO error occurs, return an error code. Otherwise,
+ ** proceed.
+ */
+ if( isHot || iHdrOff!=pPager->journalHdr ){
+ rc = sqlite3OsRead(pPager->jfd, aMagic, sizeof(aMagic), iHdrOff);
+ if( rc ){
+ return rc;
+ }
+ if( memcmp(aMagic, aJournalMagic, sizeof(aMagic))!=0 ){
+ return SQLITE_DONE;
+ }
+ }
+
+ /* Read the first three 32-bit fields of the journal header: The nRec
+ ** field, the checksum-initializer and the database size at the start
+ ** of the transaction. Return an error code if anything goes wrong.
+ */
+ if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+8, pNRec))
+ || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+12, &pPager->cksumInit))
+ || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+16, pDbSize))
+ ){
+ return rc;
+ }
+
+ if( pPager->journalOff==0 ){
+ u32 iPageSize; /* Page-size field of journal header */
+ u32 iSectorSize; /* Sector-size field of journal header */
+
+ /* Read the page-size and sector-size journal header fields. */
+ if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+20, &iSectorSize))
+ || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+24, &iPageSize))
+ ){
+ return rc;
+ }
+
+ /* Versions of SQLite prior to 3.5.8 set the page-size field of the
+ ** journal header to zero. In this case, assume that the Pager.pageSize
+ ** variable is already set to the correct page size.
+ */
+ if( iPageSize==0 ){
+ iPageSize = pPager->pageSize;
+ }
+
+ /* Check that the values read from the page-size and sector-size fields
+ ** are within range. To be 'in range', both values need to be a power
+ ** of two greater than or equal to 512 or 32, and not greater than their
+ ** respective compile time maximum limits.
+ */
+ if( iPageSize<512 || iSectorSize<32
+ || iPageSize>SQLITE_MAX_PAGE_SIZE || iSectorSize>MAX_SECTOR_SIZE
+ || ((iPageSize-1)&iPageSize)!=0 || ((iSectorSize-1)&iSectorSize)!=0
+ ){
+ /* If the either the page-size or sector-size in the journal-header is
+ ** invalid, then the process that wrote the journal-header must have
+ ** crashed before the header was synced. In this case stop reading
+ ** the journal file here.
+ */
+ return SQLITE_DONE;
+ }
+
+ /* Update the page-size to match the value read from the journal.
+ ** Use a testcase() macro to make sure that malloc failure within
+ ** PagerSetPagesize() is tested.
+ */
+ rc = sqlite3PagerSetPagesize(pPager, &iPageSize, -1);
+ testcase( rc!=SQLITE_OK );
+
+ /* Update the assumed sector-size to match the value used by
+ ** the process that created this journal. If this journal was
+ ** created by a process other than this one, then this routine
+ ** is being called from within pager_playback(). The local value
+ ** of Pager.sectorSize is restored at the end of that routine.
+ */
+ pPager->sectorSize = iSectorSize;
+ }
+
+ pPager->journalOff += JOURNAL_HDR_SZ(pPager);
+ return rc;
+}
+
+
+/*
+** Write the supplied master journal name into the journal file for pager
+** pPager at the current location. The master journal name must be the last
+** thing written to a journal file. If the pager is in full-sync mode, the
+** journal file descriptor is advanced to the next sector boundary before
+** anything is written. The format is:
+**
+** + 4 bytes: PAGER_MJ_PGNO.
+** + N bytes: Master journal filename in utf-8.
+** + 4 bytes: N (length of master journal name in bytes, no nul-terminator).
+** + 4 bytes: Master journal name checksum.
+** + 8 bytes: aJournalMagic[].
+**
+** The master journal page checksum is the sum of the bytes in the master
+** journal name, where each byte is interpreted as a signed 8-bit integer.
+**
+** If zMaster is a NULL pointer (occurs for a single database transaction),
+** this call is a no-op.
+*/
+static int writeMasterJournal(Pager *pPager, const char *zMaster){
+ int rc; /* Return code */
+ int nMaster; /* Length of string zMaster */
+ i64 iHdrOff; /* Offset of header in journal file */
+ i64 jrnlSize; /* Size of journal file on disk */
+ u32 cksum = 0; /* Checksum of string zMaster */
+
+ assert( pPager->setMaster==0 );
+ assert( !pagerUseWal(pPager) );
+
+ if( !zMaster
+ || pPager->journalMode==PAGER_JOURNALMODE_MEMORY
+ || !isOpen(pPager->jfd)
+ ){
+ return SQLITE_OK;
+ }
+ pPager->setMaster = 1;
+ assert( pPager->journalHdr <= pPager->journalOff );
+
+ /* Calculate the length in bytes and the checksum of zMaster */
+ for(nMaster=0; zMaster[nMaster]; nMaster++){
+ cksum += zMaster[nMaster];
+ }
+
+ /* If in full-sync mode, advance to the next disk sector before writing
+ ** the master journal name. This is in case the previous page written to
+ ** the journal has already been synced.
+ */
+ if( pPager->fullSync ){
+ pPager->journalOff = journalHdrOffset(pPager);
+ }
+ iHdrOff = pPager->journalOff;
+
+ /* Write the master journal data to the end of the journal file. If
+ ** an error occurs, return the error code to the caller.
+ */
+ if( (0 != (rc = write32bits(pPager->jfd, iHdrOff, PAGER_MJ_PGNO(pPager))))
+ || (0 != (rc = sqlite3OsWrite(pPager->jfd, zMaster, nMaster, iHdrOff+4)))
+ || (0 != (rc = write32bits(pPager->jfd, iHdrOff+4+nMaster, nMaster)))
+ || (0 != (rc = write32bits(pPager->jfd, iHdrOff+4+nMaster+4, cksum)))
+ || (0 != (rc = sqlite3OsWrite(pPager->jfd, aJournalMagic, 8,
+ iHdrOff+4+nMaster+8)))
+ ){
+ return rc;
+ }
+ pPager->journalOff += (nMaster+20);
+
+ /* If the pager is in peristent-journal mode, then the physical
+ ** journal-file may extend past the end of the master-journal name
+ ** and 8 bytes of magic data just written to the file. This is
+ ** dangerous because the code to rollback a hot-journal file
+ ** will not be able to find the master-journal name to determine
+ ** whether or not the journal is hot.
+ **
+ ** Easiest thing to do in this scenario is to truncate the journal
+ ** file to the required size.
+ */
+ if( SQLITE_OK==(rc = sqlite3OsFileSize(pPager->jfd, &jrnlSize))
+ && jrnlSize>pPager->journalOff
+ ){
+ rc = sqlite3OsTruncate(pPager->jfd, pPager->journalOff);
+ }
+ return rc;
+}
+
+/*
+** Discard the entire contents of the in-memory page-cache.
+*/
+static void pager_reset(Pager *pPager){
+ pPager->iDataVersion++;
+ sqlite3BackupRestart(pPager->pBackup);
+ sqlite3PcacheClear(pPager->pPCache);
+}
+
+/*
+** Return the pPager->iDataVersion value
+*/
+SQLITE_PRIVATE u32 sqlite3PagerDataVersion(Pager *pPager){
+ return pPager->iDataVersion;
+}
+
+/*
+** Free all structures in the Pager.aSavepoint[] array and set both
+** Pager.aSavepoint and Pager.nSavepoint to zero. Close the sub-journal
+** if it is open and the pager is not in exclusive mode.
+*/
+static void releaseAllSavepoints(Pager *pPager){
+ int ii; /* Iterator for looping through Pager.aSavepoint */
+ for(ii=0; iinSavepoint; ii++){
+ sqlite3BitvecDestroy(pPager->aSavepoint[ii].pInSavepoint);
+ }
+ if( !pPager->exclusiveMode || sqlite3JournalIsInMemory(pPager->sjfd) ){
+ sqlite3OsClose(pPager->sjfd);
+ }
+ sqlite3_free(pPager->aSavepoint);
+ pPager->aSavepoint = 0;
+ pPager->nSavepoint = 0;
+ pPager->nSubRec = 0;
+}
+
+/*
+** Set the bit number pgno in the PagerSavepoint.pInSavepoint
+** bitvecs of all open savepoints. Return SQLITE_OK if successful
+** or SQLITE_NOMEM if a malloc failure occurs.
+*/
+static int addToSavepointBitvecs(Pager *pPager, Pgno pgno){
+ int ii; /* Loop counter */
+ int rc = SQLITE_OK; /* Result code */
+
+ for(ii=0; iinSavepoint; ii++){
+ PagerSavepoint *p = &pPager->aSavepoint[ii];
+ if( pgno<=p->nOrig ){
+ rc |= sqlite3BitvecSet(p->pInSavepoint, pgno);
+ testcase( rc==SQLITE_NOMEM );
+ assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
+ }
+ }
+ return rc;
+}
+
+/*
+** This function is a no-op if the pager is in exclusive mode and not
+** in the ERROR state. Otherwise, it switches the pager to PAGER_OPEN
+** state.
+**
+** If the pager is not in exclusive-access mode, the database file is
+** completely unlocked. If the file is unlocked and the file-system does
+** not exhibit the UNDELETABLE_WHEN_OPEN property, the journal file is
+** closed (if it is open).
+**
+** If the pager is in ERROR state when this function is called, the
+** contents of the pager cache are discarded before switching back to
+** the OPEN state. Regardless of whether the pager is in exclusive-mode
+** or not, any journal file left in the file-system will be treated
+** as a hot-journal and rolled back the next time a read-transaction
+** is opened (by this or by any other connection).
+*/
+static void pager_unlock(Pager *pPager){
+
+ assert( pPager->eState==PAGER_READER
+ || pPager->eState==PAGER_OPEN
+ || pPager->eState==PAGER_ERROR
+ );
+
+ sqlite3BitvecDestroy(pPager->pInJournal);
+ pPager->pInJournal = 0;
+ releaseAllSavepoints(pPager);
+
+ if( pagerUseWal(pPager) ){
+ assert( !isOpen(pPager->jfd) );
+ sqlite3WalEndReadTransaction(pPager->pWal);
+ pPager->eState = PAGER_OPEN;
+ }else if( !pPager->exclusiveMode ){
+ int rc; /* Error code returned by pagerUnlockDb() */
+ int iDc = isOpen(pPager->fd)?sqlite3OsDeviceCharacteristics(pPager->fd):0;
+
+ /* If the operating system support deletion of open files, then
+ ** close the journal file when dropping the database lock. Otherwise
+ ** another connection with journal_mode=delete might delete the file
+ ** out from under us.
+ */
+ assert( (PAGER_JOURNALMODE_MEMORY & 5)!=1 );
+ assert( (PAGER_JOURNALMODE_OFF & 5)!=1 );
+ assert( (PAGER_JOURNALMODE_WAL & 5)!=1 );
+ assert( (PAGER_JOURNALMODE_DELETE & 5)!=1 );
+ assert( (PAGER_JOURNALMODE_TRUNCATE & 5)==1 );
+ assert( (PAGER_JOURNALMODE_PERSIST & 5)==1 );
+ if( 0==(iDc & SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN)
+ || 1!=(pPager->journalMode & 5)
+ ){
+ sqlite3OsClose(pPager->jfd);
+ }
+
+ /* If the pager is in the ERROR state and the call to unlock the database
+ ** file fails, set the current lock to UNKNOWN_LOCK. See the comment
+ ** above the #define for UNKNOWN_LOCK for an explanation of why this
+ ** is necessary.
+ */
+ rc = pagerUnlockDb(pPager, NO_LOCK);
+ if( rc!=SQLITE_OK && pPager->eState==PAGER_ERROR ){
+ pPager->eLock = UNKNOWN_LOCK;
+ }
+
+ /* The pager state may be changed from PAGER_ERROR to PAGER_OPEN here
+ ** without clearing the error code. This is intentional - the error
+ ** code is cleared and the cache reset in the block below.
+ */
+ assert( pPager->errCode || pPager->eState!=PAGER_ERROR );
+ pPager->changeCountDone = 0;
+ pPager->eState = PAGER_OPEN;
+ }
+
+ /* If Pager.errCode is set, the contents of the pager cache cannot be
+ ** trusted. Now that there are no outstanding references to the pager,
+ ** it can safely move back to PAGER_OPEN state. This happens in both
+ ** normal and exclusive-locking mode.
+ */
+ assert( pPager->errCode==SQLITE_OK || !MEMDB );
+ if( pPager->errCode ){
+ if( pPager->tempFile==0 ){
+ pager_reset(pPager);
+ pPager->changeCountDone = 0;
+ pPager->eState = PAGER_OPEN;
+ }else{
+ pPager->eState = (isOpen(pPager->jfd) ? PAGER_OPEN : PAGER_READER);
+ }
+ if( USEFETCH(pPager) ) sqlite3OsUnfetch(pPager->fd, 0, 0);
+ pPager->errCode = SQLITE_OK;
+ setGetterMethod(pPager);
+ }
+
+ pPager->journalOff = 0;
+ pPager->journalHdr = 0;
+ pPager->setMaster = 0;
+}
+
+/*
+** This function is called whenever an IOERR or FULL error that requires
+** the pager to transition into the ERROR state may ahve occurred.
+** The first argument is a pointer to the pager structure, the second
+** the error-code about to be returned by a pager API function. The
+** value returned is a copy of the second argument to this function.
+**
+** If the second argument is SQLITE_FULL, SQLITE_IOERR or one of the
+** IOERR sub-codes, the pager enters the ERROR state and the error code
+** is stored in Pager.errCode. While the pager remains in the ERROR state,
+** all major API calls on the Pager will immediately return Pager.errCode.
+**
+** The ERROR state indicates that the contents of the pager-cache
+** cannot be trusted. This state can be cleared by completely discarding
+** the contents of the pager-cache. If a transaction was active when
+** the persistent error occurred, then the rollback journal may need
+** to be replayed to restore the contents of the database file (as if
+** it were a hot-journal).
+*/
+static int pager_error(Pager *pPager, int rc){
+ int rc2 = rc & 0xff;
+ assert( rc==SQLITE_OK || !MEMDB );
+ assert(
+ pPager->errCode==SQLITE_FULL ||
+ pPager->errCode==SQLITE_OK ||
+ (pPager->errCode & 0xff)==SQLITE_IOERR
+ );
+ if( rc2==SQLITE_FULL || rc2==SQLITE_IOERR ){
+ pPager->errCode = rc;
+ pPager->eState = PAGER_ERROR;
+ setGetterMethod(pPager);
+ }
+ return rc;
+}
+
+static int pager_truncate(Pager *pPager, Pgno nPage);
+
+/*
+** The write transaction open on pPager is being committed (bCommit==1)
+** or rolled back (bCommit==0).
+**
+** Return TRUE if and only if all dirty pages should be flushed to disk.
+**
+** Rules:
+**
+** * For non-TEMP databases, always sync to disk. This is necessary
+** for transactions to be durable.
+**
+** * Sync TEMP database only on a COMMIT (not a ROLLBACK) when the backing
+** file has been created already (via a spill on pagerStress()) and
+** when the number of dirty pages in memory exceeds 25% of the total
+** cache size.
+*/
+static int pagerFlushOnCommit(Pager *pPager, int bCommit){
+ if( pPager->tempFile==0 ) return 1;
+ if( !bCommit ) return 0;
+ if( !isOpen(pPager->fd) ) return 0;
+ return (sqlite3PCachePercentDirty(pPager->pPCache)>=25);
+}
+
+/*
+** This routine ends a transaction. A transaction is usually ended by
+** either a COMMIT or a ROLLBACK operation. This routine may be called
+** after rollback of a hot-journal, or if an error occurs while opening
+** the journal file or writing the very first journal-header of a
+** database transaction.
+**
+** This routine is never called in PAGER_ERROR state. If it is called
+** in PAGER_NONE or PAGER_SHARED state and the lock held is less
+** exclusive than a RESERVED lock, it is a no-op.
+**
+** Otherwise, any active savepoints are released.
+**
+** If the journal file is open, then it is "finalized". Once a journal
+** file has been finalized it is not possible to use it to roll back a
+** transaction. Nor will it be considered to be a hot-journal by this
+** or any other database connection. Exactly how a journal is finalized
+** depends on whether or not the pager is running in exclusive mode and
+** the current journal-mode (Pager.journalMode value), as follows:
+**
+** journalMode==MEMORY
+** Journal file descriptor is simply closed. This destroys an
+** in-memory journal.
+**
+** journalMode==TRUNCATE
+** Journal file is truncated to zero bytes in size.
+**
+** journalMode==PERSIST
+** The first 28 bytes of the journal file are zeroed. This invalidates
+** the first journal header in the file, and hence the entire journal
+** file. An invalid journal file cannot be rolled back.
+**
+** journalMode==DELETE
+** The journal file is closed and deleted using sqlite3OsDelete().
+**
+** If the pager is running in exclusive mode, this method of finalizing
+** the journal file is never used. Instead, if the journalMode is
+** DELETE and the pager is in exclusive mode, the method described under
+** journalMode==PERSIST is used instead.
+**
+** After the journal is finalized, the pager moves to PAGER_READER state.
+** If running in non-exclusive rollback mode, the lock on the file is
+** downgraded to a SHARED_LOCK.
+**
+** SQLITE_OK is returned if no error occurs. If an error occurs during
+** any of the IO operations to finalize the journal file or unlock the
+** database then the IO error code is returned to the user. If the
+** operation to finalize the journal file fails, then the code still
+** tries to unlock the database file if not in exclusive mode. If the
+** unlock operation fails as well, then the first error code related
+** to the first error encountered (the journal finalization one) is
+** returned.
+*/
+static int pager_end_transaction(Pager *pPager, int hasMaster, int bCommit){
+ int rc = SQLITE_OK; /* Error code from journal finalization operation */
+ int rc2 = SQLITE_OK; /* Error code from db file unlock operation */
+
+ /* Do nothing if the pager does not have an open write transaction
+ ** or at least a RESERVED lock. This function may be called when there
+ ** is no write-transaction active but a RESERVED or greater lock is
+ ** held under two circumstances:
+ **
+ ** 1. After a successful hot-journal rollback, it is called with
+ ** eState==PAGER_NONE and eLock==EXCLUSIVE_LOCK.
+ **
+ ** 2. If a connection with locking_mode=exclusive holding an EXCLUSIVE
+ ** lock switches back to locking_mode=normal and then executes a
+ ** read-transaction, this function is called with eState==PAGER_READER
+ ** and eLock==EXCLUSIVE_LOCK when the read-transaction is closed.
+ */
+ assert( assert_pager_state(pPager) );
+ assert( pPager->eState!=PAGER_ERROR );
+ if( pPager->eStateeLockjfd) || pPager->pInJournal==0
+ || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_BATCH_ATOMIC)
+ );
+ if( isOpen(pPager->jfd) ){
+ assert( !pagerUseWal(pPager) );
+
+ /* Finalize the journal file. */
+ if( sqlite3JournalIsInMemory(pPager->jfd) ){
+ /* assert( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ); */
+ sqlite3OsClose(pPager->jfd);
+ }else if( pPager->journalMode==PAGER_JOURNALMODE_TRUNCATE ){
+ if( pPager->journalOff==0 ){
+ rc = SQLITE_OK;
+ }else{
+ rc = sqlite3OsTruncate(pPager->jfd, 0);
+ if( rc==SQLITE_OK && pPager->fullSync ){
+ /* Make sure the new file size is written into the inode right away.
+ ** Otherwise the journal might resurrect following a power loss and
+ ** cause the last transaction to roll back. See
+ ** https://bugzilla.mozilla.org/show_bug.cgi?id=1072773
+ */
+ rc = sqlite3OsSync(pPager->jfd, pPager->syncFlags);
+ }
+ }
+ pPager->journalOff = 0;
+ }else if( pPager->journalMode==PAGER_JOURNALMODE_PERSIST
+ || (pPager->exclusiveMode && pPager->journalMode!=PAGER_JOURNALMODE_WAL)
+ ){
+ rc = zeroJournalHdr(pPager, hasMaster||pPager->tempFile);
+ pPager->journalOff = 0;
+ }else{
+ /* This branch may be executed with Pager.journalMode==MEMORY if
+ ** a hot-journal was just rolled back. In this case the journal
+ ** file should be closed and deleted. If this connection writes to
+ ** the database file, it will do so using an in-memory journal.
+ */
+ int bDelete = !pPager->tempFile;
+ assert( sqlite3JournalIsInMemory(pPager->jfd)==0 );
+ assert( pPager->journalMode==PAGER_JOURNALMODE_DELETE
+ || pPager->journalMode==PAGER_JOURNALMODE_MEMORY
+ || pPager->journalMode==PAGER_JOURNALMODE_WAL
+ );
+ sqlite3OsClose(pPager->jfd);
+ if( bDelete ){
+ rc = sqlite3OsDelete(pPager->pVfs, pPager->zJournal, pPager->extraSync);
+ }
+ }
+ }
+
+#ifdef SQLITE_CHECK_PAGES
+ sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
+ if( pPager->dbSize==0 && sqlite3PcacheRefCount(pPager->pPCache)>0 ){
+ PgHdr *p = sqlite3PagerLookup(pPager, 1);
+ if( p ){
+ p->pageHash = 0;
+ sqlite3PagerUnrefNotNull(p);
+ }
+ }
+#endif
+
+ sqlite3BitvecDestroy(pPager->pInJournal);
+ pPager->pInJournal = 0;
+ pPager->nRec = 0;
+ if( rc==SQLITE_OK ){
+ if( MEMDB || pagerFlushOnCommit(pPager, bCommit) ){
+ sqlite3PcacheCleanAll(pPager->pPCache);
+ }else{
+ sqlite3PcacheClearWritable(pPager->pPCache);
+ }
+ sqlite3PcacheTruncate(pPager->pPCache, pPager->dbSize);
+ }
+
+ if( pagerUseWal(pPager) ){
+ /* Drop the WAL write-lock, if any. Also, if the connection was in
+ ** locking_mode=exclusive mode but is no longer, drop the EXCLUSIVE
+ ** lock held on the database file.
+ */
+ rc2 = sqlite3WalEndWriteTransaction(pPager->pWal);
+ assert( rc2==SQLITE_OK );
+ }else if( rc==SQLITE_OK && bCommit && pPager->dbFileSize>pPager->dbSize ){
+ /* This branch is taken when committing a transaction in rollback-journal
+ ** mode if the database file on disk is larger than the database image.
+ ** At this point the journal has been finalized and the transaction
+ ** successfully committed, but the EXCLUSIVE lock is still held on the
+ ** file. So it is safe to truncate the database file to its minimum
+ ** required size. */
+ assert( pPager->eLock==EXCLUSIVE_LOCK );
+ rc = pager_truncate(pPager, pPager->dbSize);
+ }
+
+ if( rc==SQLITE_OK && bCommit ){
+ rc = sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_COMMIT_PHASETWO, 0);
+ if( rc==SQLITE_NOTFOUND ) rc = SQLITE_OK;
+ }
+
+ if( !pPager->exclusiveMode
+ && (!pagerUseWal(pPager) || sqlite3WalExclusiveMode(pPager->pWal, 0))
+ ){
+ rc2 = pagerUnlockDb(pPager, SHARED_LOCK);
+ pPager->changeCountDone = 0;
+ }
+ pPager->eState = PAGER_READER;
+ pPager->setMaster = 0;
+
+ return (rc==SQLITE_OK?rc2:rc);
+}
+
+/*
+** Execute a rollback if a transaction is active and unlock the
+** database file.
+**
+** If the pager has already entered the ERROR state, do not attempt
+** the rollback at this time. Instead, pager_unlock() is called. The
+** call to pager_unlock() will discard all in-memory pages, unlock
+** the database file and move the pager back to OPEN state. If this
+** means that there is a hot-journal left in the file-system, the next
+** connection to obtain a shared lock on the pager (which may be this one)
+** will roll it back.
+**
+** If the pager has not already entered the ERROR state, but an IO or
+** malloc error occurs during a rollback, then this will itself cause
+** the pager to enter the ERROR state. Which will be cleared by the
+** call to pager_unlock(), as described above.
+*/
+static void pagerUnlockAndRollback(Pager *pPager){
+ if( pPager->eState!=PAGER_ERROR && pPager->eState!=PAGER_OPEN ){
+ assert( assert_pager_state(pPager) );
+ if( pPager->eState>=PAGER_WRITER_LOCKED ){
+ sqlite3BeginBenignMalloc();
+ sqlite3PagerRollback(pPager);
+ sqlite3EndBenignMalloc();
+ }else if( !pPager->exclusiveMode ){
+ assert( pPager->eState==PAGER_READER );
+ pager_end_transaction(pPager, 0, 0);
+ }
+ }
+ pager_unlock(pPager);
+}
+
+/*
+** Parameter aData must point to a buffer of pPager->pageSize bytes
+** of data. Compute and return a checksum based ont the contents of the
+** page of data and the current value of pPager->cksumInit.
+**
+** This is not a real checksum. It is really just the sum of the
+** random initial value (pPager->cksumInit) and every 200th byte
+** of the page data, starting with byte offset (pPager->pageSize%200).
+** Each byte is interpreted as an 8-bit unsigned integer.
+**
+** Changing the formula used to compute this checksum results in an
+** incompatible journal file format.
+**
+** If journal corruption occurs due to a power failure, the most likely
+** scenario is that one end or the other of the record will be changed.
+** It is much less likely that the two ends of the journal record will be
+** correct and the middle be corrupt. Thus, this "checksum" scheme,
+** though fast and simple, catches the mostly likely kind of corruption.
+*/
+static u32 pager_cksum(Pager *pPager, const u8 *aData){
+ u32 cksum = pPager->cksumInit; /* Checksum value to return */
+ int i = pPager->pageSize-200; /* Loop counter */
+ while( i>0 ){
+ cksum += aData[i];
+ i -= 200;
+ }
+ return cksum;
+}
+
+/*
+** Report the current page size and number of reserved bytes back
+** to the codec.
+*/
+#ifdef SQLITE_HAS_CODEC
+static void pagerReportSize(Pager *pPager){
+ if( pPager->xCodecSizeChng ){
+ pPager->xCodecSizeChng(pPager->pCodec, pPager->pageSize,
+ (int)pPager->nReserve);
+ }
+}
+#else
+# define pagerReportSize(X) /* No-op if we do not support a codec */
+#endif
+
+#ifdef SQLITE_HAS_CODEC
+/*
+** Make sure the number of reserved bits is the same in the destination
+** pager as it is in the source. This comes up when a VACUUM changes the
+** number of reserved bits to the "optimal" amount.
+*/
+SQLITE_PRIVATE void sqlite3PagerAlignReserve(Pager *pDest, Pager *pSrc){
+ if( pDest->nReserve!=pSrc->nReserve ){
+ pDest->nReserve = pSrc->nReserve;
+ pagerReportSize(pDest);
+ }
+}
+#endif
+
+/*
+** Read a single page from either the journal file (if isMainJrnl==1) or
+** from the sub-journal (if isMainJrnl==0) and playback that page.
+** The page begins at offset *pOffset into the file. The *pOffset
+** value is increased to the start of the next page in the journal.
+**
+** The main rollback journal uses checksums - the statement journal does
+** not.
+**
+** If the page number of the page record read from the (sub-)journal file
+** is greater than the current value of Pager.dbSize, then playback is
+** skipped and SQLITE_OK is returned.
+**
+** If pDone is not NULL, then it is a record of pages that have already
+** been played back. If the page at *pOffset has already been played back
+** (if the corresponding pDone bit is set) then skip the playback.
+** Make sure the pDone bit corresponding to the *pOffset page is set
+** prior to returning.
+**
+** If the page record is successfully read from the (sub-)journal file
+** and played back, then SQLITE_OK is returned. If an IO error occurs
+** while reading the record from the (sub-)journal file or while writing
+** to the database file, then the IO error code is returned. If data
+** is successfully read from the (sub-)journal file but appears to be
+** corrupted, SQLITE_DONE is returned. Data is considered corrupted in
+** two circumstances:
+**
+** * If the record page-number is illegal (0 or PAGER_MJ_PGNO), or
+** * If the record is being rolled back from the main journal file
+** and the checksum field does not match the record content.
+**
+** Neither of these two scenarios are possible during a savepoint rollback.
+**
+** If this is a savepoint rollback, then memory may have to be dynamically
+** allocated by this function. If this is the case and an allocation fails,
+** SQLITE_NOMEM is returned.
+*/
+static int pager_playback_one_page(
+ Pager *pPager, /* The pager being played back */
+ i64 *pOffset, /* Offset of record to playback */
+ Bitvec *pDone, /* Bitvec of pages already played back */
+ int isMainJrnl, /* 1 -> main journal. 0 -> sub-journal. */
+ int isSavepnt /* True for a savepoint rollback */
+){
+ int rc;
+ PgHdr *pPg; /* An existing page in the cache */
+ Pgno pgno; /* The page number of a page in journal */
+ u32 cksum; /* Checksum used for sanity checking */
+ char *aData; /* Temporary storage for the page */
+ sqlite3_file *jfd; /* The file descriptor for the journal file */
+ int isSynced; /* True if journal page is synced */
+#ifdef SQLITE_HAS_CODEC
+ /* The jrnlEnc flag is true if Journal pages should be passed through
+ ** the codec. It is false for pure in-memory journals. */
+ const int jrnlEnc = (isMainJrnl || pPager->subjInMemory==0);
+#endif
+
+ assert( (isMainJrnl&~1)==0 ); /* isMainJrnl is 0 or 1 */
+ assert( (isSavepnt&~1)==0 ); /* isSavepnt is 0 or 1 */
+ assert( isMainJrnl || pDone ); /* pDone always used on sub-journals */
+ assert( isSavepnt || pDone==0 ); /* pDone never used on non-savepoint */
+
+ aData = pPager->pTmpSpace;
+ assert( aData ); /* Temp storage must have already been allocated */
+ assert( pagerUseWal(pPager)==0 || (!isMainJrnl && isSavepnt) );
+
+ /* Either the state is greater than PAGER_WRITER_CACHEMOD (a transaction
+ ** or savepoint rollback done at the request of the caller) or this is
+ ** a hot-journal rollback. If it is a hot-journal rollback, the pager
+ ** is in state OPEN and holds an EXCLUSIVE lock. Hot-journal rollback
+ ** only reads from the main journal, not the sub-journal.
+ */
+ assert( pPager->eState>=PAGER_WRITER_CACHEMOD
+ || (pPager->eState==PAGER_OPEN && pPager->eLock==EXCLUSIVE_LOCK)
+ );
+ assert( pPager->eState>=PAGER_WRITER_CACHEMOD || isMainJrnl );
+
+ /* Read the page number and page data from the journal or sub-journal
+ ** file. Return an error code to the caller if an IO error occurs.
+ */
+ jfd = isMainJrnl ? pPager->jfd : pPager->sjfd;
+ rc = read32bits(jfd, *pOffset, &pgno);
+ if( rc!=SQLITE_OK ) return rc;
+ rc = sqlite3OsRead(jfd, (u8*)aData, pPager->pageSize, (*pOffset)+4);
+ if( rc!=SQLITE_OK ) return rc;
+ *pOffset += pPager->pageSize + 4 + isMainJrnl*4;
+
+ /* Sanity checking on the page. This is more important that I originally
+ ** thought. If a power failure occurs while the journal is being written,
+ ** it could cause invalid data to be written into the journal. We need to
+ ** detect this invalid data (with high probability) and ignore it.
+ */
+ if( pgno==0 || pgno==PAGER_MJ_PGNO(pPager) ){
+ assert( !isSavepnt );
+ return SQLITE_DONE;
+ }
+ if( pgno>(Pgno)pPager->dbSize || sqlite3BitvecTest(pDone, pgno) ){
+ return SQLITE_OK;
+ }
+ if( isMainJrnl ){
+ rc = read32bits(jfd, (*pOffset)-4, &cksum);
+ if( rc ) return rc;
+ if( !isSavepnt && pager_cksum(pPager, (u8*)aData)!=cksum ){
+ return SQLITE_DONE;
+ }
+ }
+
+ /* If this page has already been played back before during the current
+ ** rollback, then don't bother to play it back again.
+ */
+ if( pDone && (rc = sqlite3BitvecSet(pDone, pgno))!=SQLITE_OK ){
+ return rc;
+ }
+
+ /* When playing back page 1, restore the nReserve setting
+ */
+ if( pgno==1 && pPager->nReserve!=((u8*)aData)[20] ){
+ pPager->nReserve = ((u8*)aData)[20];
+ pagerReportSize(pPager);
+ }
+
+ /* If the pager is in CACHEMOD state, then there must be a copy of this
+ ** page in the pager cache. In this case just update the pager cache,
+ ** not the database file. The page is left marked dirty in this case.
+ **
+ ** An exception to the above rule: If the database is in no-sync mode
+ ** and a page is moved during an incremental vacuum then the page may
+ ** not be in the pager cache. Later: if a malloc() or IO error occurs
+ ** during a Movepage() call, then the page may not be in the cache
+ ** either. So the condition described in the above paragraph is not
+ ** assert()able.
+ **
+ ** If in WRITER_DBMOD, WRITER_FINISHED or OPEN state, then we update the
+ ** pager cache if it exists and the main file. The page is then marked
+ ** not dirty. Since this code is only executed in PAGER_OPEN state for
+ ** a hot-journal rollback, it is guaranteed that the page-cache is empty
+ ** if the pager is in OPEN state.
+ **
+ ** Ticket #1171: The statement journal might contain page content that is
+ ** different from the page content at the start of the transaction.
+ ** This occurs when a page is changed prior to the start of a statement
+ ** then changed again within the statement. When rolling back such a
+ ** statement we must not write to the original database unless we know
+ ** for certain that original page contents are synced into the main rollback
+ ** journal. Otherwise, a power loss might leave modified data in the
+ ** database file without an entry in the rollback journal that can
+ ** restore the database to its original form. Two conditions must be
+ ** met before writing to the database files. (1) the database must be
+ ** locked. (2) we know that the original page content is fully synced
+ ** in the main journal either because the page is not in cache or else
+ ** the page is marked as needSync==0.
+ **
+ ** 2008-04-14: When attempting to vacuum a corrupt database file, it
+ ** is possible to fail a statement on a database that does not yet exist.
+ ** Do not attempt to write if database file has never been opened.
+ */
+ if( pagerUseWal(pPager) ){
+ pPg = 0;
+ }else{
+ pPg = sqlite3PagerLookup(pPager, pgno);
+ }
+ assert( pPg || !MEMDB );
+ assert( pPager->eState!=PAGER_OPEN || pPg==0 || pPager->tempFile );
+ PAGERTRACE(("PLAYBACK %d page %d hash(%08x) %s\n",
+ PAGERID(pPager), pgno, pager_datahash(pPager->pageSize, (u8*)aData),
+ (isMainJrnl?"main-journal":"sub-journal")
+ ));
+ if( isMainJrnl ){
+ isSynced = pPager->noSync || (*pOffset <= pPager->journalHdr);
+ }else{
+ isSynced = (pPg==0 || 0==(pPg->flags & PGHDR_NEED_SYNC));
+ }
+ if( isOpen(pPager->fd)
+ && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
+ && isSynced
+ ){
+ i64 ofst = (pgno-1)*(i64)pPager->pageSize;
+ testcase( !isSavepnt && pPg!=0 && (pPg->flags&PGHDR_NEED_SYNC)!=0 );
+ assert( !pagerUseWal(pPager) );
+
+ /* Write the data read from the journal back into the database file.
+ ** This is usually safe even for an encrypted database - as the data
+ ** was encrypted before it was written to the journal file. The exception
+ ** is if the data was just read from an in-memory sub-journal. In that
+ ** case it must be encrypted here before it is copied into the database
+ ** file. */
+#ifdef SQLITE_HAS_CODEC
+ if( !jrnlEnc ){
+ CODEC2(pPager, aData, pgno, 7, rc=SQLITE_NOMEM_BKPT, aData);
+ rc = sqlite3OsWrite(pPager->fd, (u8 *)aData, pPager->pageSize, ofst);
+ CODEC1(pPager, aData, pgno, 3, rc=SQLITE_NOMEM_BKPT);
+ }else
+#endif
+ rc = sqlite3OsWrite(pPager->fd, (u8 *)aData, pPager->pageSize, ofst);
+
+ if( pgno>pPager->dbFileSize ){
+ pPager->dbFileSize = pgno;
+ }
+ if( pPager->pBackup ){
+#ifdef SQLITE_HAS_CODEC
+ if( jrnlEnc ){
+ CODEC1(pPager, aData, pgno, 3, rc=SQLITE_NOMEM_BKPT);
+ sqlite3BackupUpdate(pPager->pBackup, pgno, (u8*)aData);
+ CODEC2(pPager, aData, pgno, 7, rc=SQLITE_NOMEM_BKPT,aData);
+ }else
+#endif
+ sqlite3BackupUpdate(pPager->pBackup, pgno, (u8*)aData);
+ }
+ }else if( !isMainJrnl && pPg==0 ){
+ /* If this is a rollback of a savepoint and data was not written to
+ ** the database and the page is not in-memory, there is a potential
+ ** problem. When the page is next fetched by the b-tree layer, it
+ ** will be read from the database file, which may or may not be
+ ** current.
+ **
+ ** There are a couple of different ways this can happen. All are quite
+ ** obscure. When running in synchronous mode, this can only happen
+ ** if the page is on the free-list at the start of the transaction, then
+ ** populated, then moved using sqlite3PagerMovepage().
+ **
+ ** The solution is to add an in-memory page to the cache containing
+ ** the data just read from the sub-journal. Mark the page as dirty
+ ** and if the pager requires a journal-sync, then mark the page as
+ ** requiring a journal-sync before it is written.
+ */
+ assert( isSavepnt );
+ assert( (pPager->doNotSpill & SPILLFLAG_ROLLBACK)==0 );
+ pPager->doNotSpill |= SPILLFLAG_ROLLBACK;
+ rc = sqlite3PagerGet(pPager, pgno, &pPg, 1);
+ assert( (pPager->doNotSpill & SPILLFLAG_ROLLBACK)!=0 );
+ pPager->doNotSpill &= ~SPILLFLAG_ROLLBACK;
+ if( rc!=SQLITE_OK ) return rc;
+ sqlite3PcacheMakeDirty(pPg);
+ }
+ if( pPg ){
+ /* No page should ever be explicitly rolled back that is in use, except
+ ** for page 1 which is held in use in order to keep the lock on the
+ ** database active. However such a page may be rolled back as a result
+ ** of an internal error resulting in an automatic call to
+ ** sqlite3PagerRollback().
+ */
+ void *pData;
+ pData = pPg->pData;
+ memcpy(pData, (u8*)aData, pPager->pageSize);
+ pPager->xReiniter(pPg);
+ /* It used to be that sqlite3PcacheMakeClean(pPg) was called here. But
+ ** that call was dangerous and had no detectable benefit since the cache
+ ** is normally cleaned by sqlite3PcacheCleanAll() after rollback and so
+ ** has been removed. */
+ pager_set_pagehash(pPg);
+
+ /* If this was page 1, then restore the value of Pager.dbFileVers.
+ ** Do this before any decoding. */
+ if( pgno==1 ){
+ memcpy(&pPager->dbFileVers, &((u8*)pData)[24],sizeof(pPager->dbFileVers));
+ }
+
+ /* Decode the page just read from disk */
+#if SQLITE_HAS_CODEC
+ if( jrnlEnc ){ CODEC1(pPager, pData, pPg->pgno, 3, rc=SQLITE_NOMEM_BKPT); }
+#endif
+ sqlite3PcacheRelease(pPg);
+ }
+ return rc;
+}
+
+/*
+** Parameter zMaster is the name of a master journal file. A single journal
+** file that referred to the master journal file has just been rolled back.
+** This routine checks if it is possible to delete the master journal file,
+** and does so if it is.
+**
+** Argument zMaster may point to Pager.pTmpSpace. So that buffer is not
+** available for use within this function.
+**
+** When a master journal file is created, it is populated with the names
+** of all of its child journals, one after another, formatted as utf-8
+** encoded text. The end of each child journal file is marked with a
+** nul-terminator byte (0x00). i.e. the entire contents of a master journal
+** file for a transaction involving two databases might be:
+**
+** "/home/bill/a.db-journal\x00/home/bill/b.db-journal\x00"
+**
+** A master journal file may only be deleted once all of its child
+** journals have been rolled back.
+**
+** This function reads the contents of the master-journal file into
+** memory and loops through each of the child journal names. For
+** each child journal, it checks if:
+**
+** * if the child journal exists, and if so
+** * if the child journal contains a reference to master journal
+** file zMaster
+**
+** If a child journal can be found that matches both of the criteria
+** above, this function returns without doing anything. Otherwise, if
+** no such child journal can be found, file zMaster is deleted from
+** the file-system using sqlite3OsDelete().
+**
+** If an IO error within this function, an error code is returned. This
+** function allocates memory by calling sqlite3Malloc(). If an allocation
+** fails, SQLITE_NOMEM is returned. Otherwise, if no IO or malloc errors
+** occur, SQLITE_OK is returned.
+**
+** TODO: This function allocates a single block of memory to load
+** the entire contents of the master journal file. This could be
+** a couple of kilobytes or so - potentially larger than the page
+** size.
+*/
+static int pager_delmaster(Pager *pPager, const char *zMaster){
+ sqlite3_vfs *pVfs = pPager->pVfs;
+ int rc; /* Return code */
+ sqlite3_file *pMaster; /* Malloc'd master-journal file descriptor */
+ sqlite3_file *pJournal; /* Malloc'd child-journal file descriptor */
+ char *zMasterJournal = 0; /* Contents of master journal file */
+ i64 nMasterJournal; /* Size of master journal file */
+ char *zJournal; /* Pointer to one journal within MJ file */
+ char *zMasterPtr; /* Space to hold MJ filename from a journal file */
+ int nMasterPtr; /* Amount of space allocated to zMasterPtr[] */
+
+ /* Allocate space for both the pJournal and pMaster file descriptors.
+ ** If successful, open the master journal file for reading.
+ */
+ pMaster = (sqlite3_file *)sqlite3MallocZero(pVfs->szOsFile * 2);
+ pJournal = (sqlite3_file *)(((u8 *)pMaster) + pVfs->szOsFile);
+ if( !pMaster ){
+ rc = SQLITE_NOMEM_BKPT;
+ }else{
+ const int flags = (SQLITE_OPEN_READONLY|SQLITE_OPEN_MASTER_JOURNAL);
+ rc = sqlite3OsOpen(pVfs, zMaster, pMaster, flags, 0);
+ }
+ if( rc!=SQLITE_OK ) goto delmaster_out;
+
+ /* Load the entire master journal file into space obtained from
+ ** sqlite3_malloc() and pointed to by zMasterJournal. Also obtain
+ ** sufficient space (in zMasterPtr) to hold the names of master
+ ** journal files extracted from regular rollback-journals.
+ */
+ rc = sqlite3OsFileSize(pMaster, &nMasterJournal);
+ if( rc!=SQLITE_OK ) goto delmaster_out;
+ nMasterPtr = pVfs->mxPathname+1;
+ zMasterJournal = sqlite3Malloc(nMasterJournal + nMasterPtr + 1);
+ if( !zMasterJournal ){
+ rc = SQLITE_NOMEM_BKPT;
+ goto delmaster_out;
+ }
+ zMasterPtr = &zMasterJournal[nMasterJournal+1];
+ rc = sqlite3OsRead(pMaster, zMasterJournal, (int)nMasterJournal, 0);
+ if( rc!=SQLITE_OK ) goto delmaster_out;
+ zMasterJournal[nMasterJournal] = 0;
+
+ zJournal = zMasterJournal;
+ while( (zJournal-zMasterJournal)pageSize bytes).
+** If the file on disk is currently larger than nPage pages, then use the VFS
+** xTruncate() method to truncate it.
+**
+** Or, it might be the case that the file on disk is smaller than
+** nPage pages. Some operating system implementations can get confused if
+** you try to truncate a file to some size that is larger than it
+** currently is, so detect this case and write a single zero byte to
+** the end of the new file instead.
+**
+** If successful, return SQLITE_OK. If an IO error occurs while modifying
+** the database file, return the error code to the caller.
+*/
+static int pager_truncate(Pager *pPager, Pgno nPage){
+ int rc = SQLITE_OK;
+ assert( pPager->eState!=PAGER_ERROR );
+ assert( pPager->eState!=PAGER_READER );
+
+ if( isOpen(pPager->fd)
+ && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
+ ){
+ i64 currentSize, newSize;
+ int szPage = pPager->pageSize;
+ assert( pPager->eLock==EXCLUSIVE_LOCK );
+ /* TODO: Is it safe to use Pager.dbFileSize here? */
+ rc = sqlite3OsFileSize(pPager->fd, ¤tSize);
+ newSize = szPage*(i64)nPage;
+ if( rc==SQLITE_OK && currentSize!=newSize ){
+ if( currentSize>newSize ){
+ rc = sqlite3OsTruncate(pPager->fd, newSize);
+ }else if( (currentSize+szPage)<=newSize ){
+ char *pTmp = pPager->pTmpSpace;
+ memset(pTmp, 0, szPage);
+ testcase( (newSize-szPage) == currentSize );
+ testcase( (newSize-szPage) > currentSize );
+ rc = sqlite3OsWrite(pPager->fd, pTmp, szPage, newSize-szPage);
+ }
+ if( rc==SQLITE_OK ){
+ pPager->dbFileSize = nPage;
+ }
+ }
+ }
+ return rc;
+}
+
+/*
+** Return a sanitized version of the sector-size of OS file pFile. The
+** return value is guaranteed to lie between 32 and MAX_SECTOR_SIZE.
+*/
+SQLITE_PRIVATE int sqlite3SectorSize(sqlite3_file *pFile){
+ int iRet = sqlite3OsSectorSize(pFile);
+ if( iRet<32 ){
+ iRet = 512;
+ }else if( iRet>MAX_SECTOR_SIZE ){
+ assert( MAX_SECTOR_SIZE>=512 );
+ iRet = MAX_SECTOR_SIZE;
+ }
+ return iRet;
+}
+
+/*
+** Set the value of the Pager.sectorSize variable for the given
+** pager based on the value returned by the xSectorSize method
+** of the open database file. The sector size will be used
+** to determine the size and alignment of journal header and
+** master journal pointers within created journal files.
+**
+** For temporary files the effective sector size is always 512 bytes.
+**
+** Otherwise, for non-temporary files, the effective sector size is
+** the value returned by the xSectorSize() method rounded up to 32 if
+** it is less than 32, or rounded down to MAX_SECTOR_SIZE if it
+** is greater than MAX_SECTOR_SIZE.
+**
+** If the file has the SQLITE_IOCAP_POWERSAFE_OVERWRITE property, then set
+** the effective sector size to its minimum value (512). The purpose of
+** pPager->sectorSize is to define the "blast radius" of bytes that
+** might change if a crash occurs while writing to a single byte in
+** that range. But with POWERSAFE_OVERWRITE, the blast radius is zero
+** (that is what POWERSAFE_OVERWRITE means), so we minimize the sector
+** size. For backwards compatibility of the rollback journal file format,
+** we cannot reduce the effective sector size below 512.
+*/
+static void setSectorSize(Pager *pPager){
+ assert( isOpen(pPager->fd) || pPager->tempFile );
+
+ if( pPager->tempFile
+ || (sqlite3OsDeviceCharacteristics(pPager->fd) &
+ SQLITE_IOCAP_POWERSAFE_OVERWRITE)!=0
+ ){
+ /* Sector size doesn't matter for temporary files. Also, the file
+ ** may not have been opened yet, in which case the OsSectorSize()
+ ** call will segfault. */
+ pPager->sectorSize = 512;
+ }else{
+ pPager->sectorSize = sqlite3SectorSize(pPager->fd);
+ }
+}
+
+/*
+** Playback the journal and thus restore the database file to
+** the state it was in before we started making changes.
+**
+** The journal file format is as follows:
+**
+** (1) 8 byte prefix. A copy of aJournalMagic[].
+** (2) 4 byte big-endian integer which is the number of valid page records
+** in the journal. If this value is 0xffffffff, then compute the
+** number of page records from the journal size.
+** (3) 4 byte big-endian integer which is the initial value for the
+** sanity checksum.
+** (4) 4 byte integer which is the number of pages to truncate the
+** database to during a rollback.
+** (5) 4 byte big-endian integer which is the sector size. The header
+** is this many bytes in size.
+** (6) 4 byte big-endian integer which is the page size.
+** (7) zero padding out to the next sector size.
+** (8) Zero or more pages instances, each as follows:
+** + 4 byte page number.
+** + pPager->pageSize bytes of data.
+** + 4 byte checksum
+**
+** When we speak of the journal header, we mean the first 7 items above.
+** Each entry in the journal is an instance of the 8th item.
+**
+** Call the value from the second bullet "nRec". nRec is the number of
+** valid page entries in the journal. In most cases, you can compute the
+** value of nRec from the size of the journal file. But if a power
+** failure occurred while the journal was being written, it could be the
+** case that the size of the journal file had already been increased but
+** the extra entries had not yet made it safely to disk. In such a case,
+** the value of nRec computed from the file size would be too large. For
+** that reason, we always use the nRec value in the header.
+**
+** If the nRec value is 0xffffffff it means that nRec should be computed
+** from the file size. This value is used when the user selects the
+** no-sync option for the journal. A power failure could lead to corruption
+** in this case. But for things like temporary table (which will be
+** deleted when the power is restored) we don't care.
+**
+** If the file opened as the journal file is not a well-formed
+** journal file then all pages up to the first corrupted page are rolled
+** back (or no pages if the journal header is corrupted). The journal file
+** is then deleted and SQLITE_OK returned, just as if no corruption had
+** been encountered.
+**
+** If an I/O or malloc() error occurs, the journal-file is not deleted
+** and an error code is returned.
+**
+** The isHot parameter indicates that we are trying to rollback a journal
+** that might be a hot journal. Or, it could be that the journal is
+** preserved because of JOURNALMODE_PERSIST or JOURNALMODE_TRUNCATE.
+** If the journal really is hot, reset the pager cache prior rolling
+** back any content. If the journal is merely persistent, no reset is
+** needed.
+*/
+static int pager_playback(Pager *pPager, int isHot){
+ sqlite3_vfs *pVfs = pPager->pVfs;
+ i64 szJ; /* Size of the journal file in bytes */
+ u32 nRec; /* Number of Records in the journal */
+ u32 u; /* Unsigned loop counter */
+ Pgno mxPg = 0; /* Size of the original file in pages */
+ int rc; /* Result code of a subroutine */
+ int res = 1; /* Value returned by sqlite3OsAccess() */
+ char *zMaster = 0; /* Name of master journal file if any */
+ int needPagerReset; /* True to reset page prior to first page rollback */
+ int nPlayback = 0; /* Total number of pages restored from journal */
+ u32 savedPageSize = pPager->pageSize;
+
+ /* Figure out how many records are in the journal. Abort early if
+ ** the journal is empty.
+ */
+ assert( isOpen(pPager->jfd) );
+ rc = sqlite3OsFileSize(pPager->jfd, &szJ);
+ if( rc!=SQLITE_OK ){
+ goto end_playback;
+ }
+
+ /* Read the master journal name from the journal, if it is present.
+ ** If a master journal file name is specified, but the file is not
+ ** present on disk, then the journal is not hot and does not need to be
+ ** played back.
+ **
+ ** TODO: Technically the following is an error because it assumes that
+ ** buffer Pager.pTmpSpace is (mxPathname+1) bytes or larger. i.e. that
+ ** (pPager->pageSize >= pPager->pVfs->mxPathname+1). Using os_unix.c,
+ ** mxPathname is 512, which is the same as the minimum allowable value
+ ** for pageSize.
+ */
+ zMaster = pPager->pTmpSpace;
+ rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
+ if( rc==SQLITE_OK && zMaster[0] ){
+ rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
+ }
+ zMaster = 0;
+ if( rc!=SQLITE_OK || !res ){
+ goto end_playback;
+ }
+ pPager->journalOff = 0;
+ needPagerReset = isHot;
+
+ /* This loop terminates either when a readJournalHdr() or
+ ** pager_playback_one_page() call returns SQLITE_DONE or an IO error
+ ** occurs.
+ */
+ while( 1 ){
+ /* Read the next journal header from the journal file. If there are
+ ** not enough bytes left in the journal file for a complete header, or
+ ** it is corrupted, then a process must have failed while writing it.
+ ** This indicates nothing more needs to be rolled back.
+ */
+ rc = readJournalHdr(pPager, isHot, szJ, &nRec, &mxPg);
+ if( rc!=SQLITE_OK ){
+ if( rc==SQLITE_DONE ){
+ rc = SQLITE_OK;
+ }
+ goto end_playback;
+ }
+
+ /* If nRec is 0xffffffff, then this journal was created by a process
+ ** working in no-sync mode. This means that the rest of the journal
+ ** file consists of pages, there are no more journal headers. Compute
+ ** the value of nRec based on this assumption.
+ */
+ if( nRec==0xffffffff ){
+ assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) );
+ nRec = (int)((szJ - JOURNAL_HDR_SZ(pPager))/JOURNAL_PG_SZ(pPager));
+ }
+
+ /* If nRec is 0 and this rollback is of a transaction created by this
+ ** process and if this is the final header in the journal, then it means
+ ** that this part of the journal was being filled but has not yet been
+ ** synced to disk. Compute the number of pages based on the remaining
+ ** size of the file.
+ **
+ ** The third term of the test was added to fix ticket #2565.
+ ** When rolling back a hot journal, nRec==0 always means that the next
+ ** chunk of the journal contains zero pages to be rolled back. But
+ ** when doing a ROLLBACK and the nRec==0 chunk is the last chunk in
+ ** the journal, it means that the journal might contain additional
+ ** pages that need to be rolled back and that the number of pages
+ ** should be computed based on the journal file size.
+ */
+ if( nRec==0 && !isHot &&
+ pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff ){
+ nRec = (int)((szJ - pPager->journalOff) / JOURNAL_PG_SZ(pPager));
+ }
+
+ /* If this is the first header read from the journal, truncate the
+ ** database file back to its original size.
+ */
+ if( pPager->journalOff==JOURNAL_HDR_SZ(pPager) ){
+ rc = pager_truncate(pPager, mxPg);
+ if( rc!=SQLITE_OK ){
+ goto end_playback;
+ }
+ pPager->dbSize = mxPg;
+ }
+
+ /* Copy original pages out of the journal and back into the
+ ** database file and/or page cache.
+ */
+ for(u=0; ujournalOff,0,1,0);
+ if( rc==SQLITE_OK ){
+ nPlayback++;
+ }else{
+ if( rc==SQLITE_DONE ){
+ pPager->journalOff = szJ;
+ break;
+ }else if( rc==SQLITE_IOERR_SHORT_READ ){
+ /* If the journal has been truncated, simply stop reading and
+ ** processing the journal. This might happen if the journal was
+ ** not completely written and synced prior to a crash. In that
+ ** case, the database should have never been written in the
+ ** first place so it is OK to simply abandon the rollback. */
+ rc = SQLITE_OK;
+ goto end_playback;
+ }else{
+ /* If we are unable to rollback, quit and return the error
+ ** code. This will cause the pager to enter the error state
+ ** so that no further harm will be done. Perhaps the next
+ ** process to come along will be able to rollback the database.
+ */
+ goto end_playback;
+ }
+ }
+ }
+ }
+ /*NOTREACHED*/
+ assert( 0 );
+
+end_playback:
+ if( rc==SQLITE_OK ){
+ rc = sqlite3PagerSetPagesize(pPager, &savedPageSize, -1);
+ }
+ /* Following a rollback, the database file should be back in its original
+ ** state prior to the start of the transaction, so invoke the
+ ** SQLITE_FCNTL_DB_UNCHANGED file-control method to disable the
+ ** assertion that the transaction counter was modified.
+ */
+#ifdef SQLITE_DEBUG
+ sqlite3OsFileControlHint(pPager->fd,SQLITE_FCNTL_DB_UNCHANGED,0);
+#endif
+
+ /* If this playback is happening automatically as a result of an IO or
+ ** malloc error that occurred after the change-counter was updated but
+ ** before the transaction was committed, then the change-counter
+ ** modification may just have been reverted. If this happens in exclusive
+ ** mode, then subsequent transactions performed by the connection will not
+ ** update the change-counter at all. This may lead to cache inconsistency
+ ** problems for other processes at some point in the future. So, just
+ ** in case this has happened, clear the changeCountDone flag now.
+ */
+ pPager->changeCountDone = pPager->tempFile;
+
+ if( rc==SQLITE_OK ){
+ zMaster = pPager->pTmpSpace;
+ rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
+ testcase( rc!=SQLITE_OK );
+ }
+ if( rc==SQLITE_OK
+ && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
+ ){
+ rc = sqlite3PagerSync(pPager, 0);
+ }
+ if( rc==SQLITE_OK ){
+ rc = pager_end_transaction(pPager, zMaster[0]!='\0', 0);
+ testcase( rc!=SQLITE_OK );
+ }
+ if( rc==SQLITE_OK && zMaster[0] && res ){
+ /* If there was a master journal and this routine will return success,
+ ** see if it is possible to delete the master journal.
+ */
+ rc = pager_delmaster(pPager, zMaster);
+ testcase( rc!=SQLITE_OK );
+ }
+ if( isHot && nPlayback ){
+ sqlite3_log(SQLITE_NOTICE_RECOVER_ROLLBACK, "recovered %d pages from %s",
+ nPlayback, pPager->zJournal);
+ }
+
+ /* The Pager.sectorSize variable may have been updated while rolling
+ ** back a journal created by a process with a different sector size
+ ** value. Reset it to the correct value for this process.
+ */
+ setSectorSize(pPager);
+ return rc;
+}
+
+
+/*
+** Read the content for page pPg out of the database file (or out of
+** the WAL if that is where the most recent copy if found) into
+** pPg->pData. A shared lock or greater must be held on the database
+** file before this function is called.
+**
+** If page 1 is read, then the value of Pager.dbFileVers[] is set to
+** the value read from the database file.
+**
+** If an IO error occurs, then the IO error is returned to the caller.
+** Otherwise, SQLITE_OK is returned.
+*/
+static int readDbPage(PgHdr *pPg){
+ Pager *pPager = pPg->pPager; /* Pager object associated with page pPg */
+ int rc = SQLITE_OK; /* Return code */
+
+#ifndef SQLITE_OMIT_WAL
+ u32 iFrame = 0; /* Frame of WAL containing pgno */
+
+ assert( pPager->eState>=PAGER_READER && !MEMDB );
+ assert( isOpen(pPager->fd) );
+
+ if( pagerUseWal(pPager) ){
+ rc = sqlite3WalFindFrame(pPager->pWal, pPg->pgno, &iFrame);
+ if( rc ) return rc;
+ }
+ if( iFrame ){
+ rc = sqlite3WalReadFrame(pPager->pWal, iFrame,pPager->pageSize,pPg->pData);
+ }else
+#endif
+ {
+ i64 iOffset = (pPg->pgno-1)*(i64)pPager->pageSize;
+ rc = sqlite3OsRead(pPager->fd, pPg->pData, pPager->pageSize, iOffset);
+ if( rc==SQLITE_IOERR_SHORT_READ ){
+ rc = SQLITE_OK;
+ }
+ }
+
+ if( pPg->pgno==1 ){
+ if( rc ){
+ /* If the read is unsuccessful, set the dbFileVers[] to something
+ ** that will never be a valid file version. dbFileVers[] is a copy
+ ** of bytes 24..39 of the database. Bytes 28..31 should always be
+ ** zero or the size of the database in page. Bytes 32..35 and 35..39
+ ** should be page numbers which are never 0xffffffff. So filling
+ ** pPager->dbFileVers[] with all 0xff bytes should suffice.
+ **
+ ** For an encrypted database, the situation is more complex: bytes
+ ** 24..39 of the database are white noise. But the probability of
+ ** white noise equaling 16 bytes of 0xff is vanishingly small so
+ ** we should still be ok.
+ */
+ memset(pPager->dbFileVers, 0xff, sizeof(pPager->dbFileVers));
+ }else{
+ u8 *dbFileVers = &((u8*)pPg->pData)[24];
+ memcpy(&pPager->dbFileVers, dbFileVers, sizeof(pPager->dbFileVers));
+ }
+ }
+ CODEC1(pPager, pPg->pData, pPg->pgno, 3, rc = SQLITE_NOMEM_BKPT);
+
+ PAGER_INCR(sqlite3_pager_readdb_count);
+ PAGER_INCR(pPager->nRead);
+ IOTRACE(("PGIN %p %d\n", pPager, pPg->pgno));
+ PAGERTRACE(("FETCH %d page %d hash(%08x)\n",
+ PAGERID(pPager), pPg->pgno, pager_pagehash(pPg)));
+
+ return rc;
+}
+
+/*
+** Update the value of the change-counter at offsets 24 and 92 in
+** the header and the sqlite version number at offset 96.
+**
+** This is an unconditional update. See also the pager_incr_changecounter()
+** routine which only updates the change-counter if the update is actually
+** needed, as determined by the pPager->changeCountDone state variable.
+*/
+static void pager_write_changecounter(PgHdr *pPg){
+ u32 change_counter;
+
+ /* Increment the value just read and write it back to byte 24. */
+ change_counter = sqlite3Get4byte((u8*)pPg->pPager->dbFileVers)+1;
+ put32bits(((char*)pPg->pData)+24, change_counter);
+
+ /* Also store the SQLite version number in bytes 96..99 and in
+ ** bytes 92..95 store the change counter for which the version number
+ ** is valid. */
+ put32bits(((char*)pPg->pData)+92, change_counter);
+ put32bits(((char*)pPg->pData)+96, SQLITE_VERSION_NUMBER);
+}
+
+#ifndef SQLITE_OMIT_WAL
+/*
+** This function is invoked once for each page that has already been
+** written into the log file when a WAL transaction is rolled back.
+** Parameter iPg is the page number of said page. The pCtx argument
+** is actually a pointer to the Pager structure.
+**
+** If page iPg is present in the cache, and has no outstanding references,
+** it is discarded. Otherwise, if there are one or more outstanding
+** references, the page content is reloaded from the database. If the
+** attempt to reload content from the database is required and fails,
+** return an SQLite error code. Otherwise, SQLITE_OK.
+*/
+static int pagerUndoCallback(void *pCtx, Pgno iPg){
+ int rc = SQLITE_OK;
+ Pager *pPager = (Pager *)pCtx;
+ PgHdr *pPg;
+
+ assert( pagerUseWal(pPager) );
+ pPg = sqlite3PagerLookup(pPager, iPg);
+ if( pPg ){
+ if( sqlite3PcachePageRefcount(pPg)==1 ){
+ sqlite3PcacheDrop(pPg);
+ }else{
+ rc = readDbPage(pPg);
+ if( rc==SQLITE_OK ){
+ pPager->xReiniter(pPg);
+ }
+ sqlite3PagerUnrefNotNull(pPg);
+ }
+ }
+
+ /* Normally, if a transaction is rolled back, any backup processes are
+ ** updated as data is copied out of the rollback journal and into the
+ ** database. This is not generally possible with a WAL database, as
+ ** rollback involves simply truncating the log file. Therefore, if one
+ ** or more frames have already been written to the log (and therefore
+ ** also copied into the backup databases) as part of this transaction,
+ ** the backups must be restarted.
+ */
+ sqlite3BackupRestart(pPager->pBackup);
+
+ return rc;
+}
+
+/*
+** This function is called to rollback a transaction on a WAL database.
+*/
+static int pagerRollbackWal(Pager *pPager){
+ int rc; /* Return Code */
+ PgHdr *pList; /* List of dirty pages to revert */
+
+ /* For all pages in the cache that are currently dirty or have already
+ ** been written (but not committed) to the log file, do one of the
+ ** following:
+ **
+ ** + Discard the cached page (if refcount==0), or
+ ** + Reload page content from the database (if refcount>0).
+ */
+ pPager->dbSize = pPager->dbOrigSize;
+ rc = sqlite3WalUndo(pPager->pWal, pagerUndoCallback, (void *)pPager);
+ pList = sqlite3PcacheDirtyList(pPager->pPCache);
+ while( pList && rc==SQLITE_OK ){
+ PgHdr *pNext = pList->pDirty;
+ rc = pagerUndoCallback((void *)pPager, pList->pgno);
+ pList = pNext;
+ }
+
+ return rc;
+}
+
+/*
+** This function is a wrapper around sqlite3WalFrames(). As well as logging
+** the contents of the list of pages headed by pList (connected by pDirty),
+** this function notifies any active backup processes that the pages have
+** changed.
+**
+** The list of pages passed into this routine is always sorted by page number.
+** Hence, if page 1 appears anywhere on the list, it will be the first page.
+*/
+static int pagerWalFrames(
+ Pager *pPager, /* Pager object */
+ PgHdr *pList, /* List of frames to log */
+ Pgno nTruncate, /* Database size after this commit */
+ int isCommit /* True if this is a commit */
+){
+ int rc; /* Return code */
+ int nList; /* Number of pages in pList */
+ PgHdr *p; /* For looping over pages */
+
+ assert( pPager->pWal );
+ assert( pList );
+#ifdef SQLITE_DEBUG
+ /* Verify that the page list is in accending order */
+ for(p=pList; p && p->pDirty; p=p->pDirty){
+ assert( p->pgno < p->pDirty->pgno );
+ }
+#endif
+
+ assert( pList->pDirty==0 || isCommit );
+ if( isCommit ){
+ /* If a WAL transaction is being committed, there is no point in writing
+ ** any pages with page numbers greater than nTruncate into the WAL file.
+ ** They will never be read by any client. So remove them from the pDirty
+ ** list here. */
+ PgHdr **ppNext = &pList;
+ nList = 0;
+ for(p=pList; (*ppNext = p)!=0; p=p->pDirty){
+ if( p->pgno<=nTruncate ){
+ ppNext = &p->pDirty;
+ nList++;
+ }
+ }
+ assert( pList );
+ }else{
+ nList = 1;
+ }
+ pPager->aStat[PAGER_STAT_WRITE] += nList;
+
+ if( pList->pgno==1 ) pager_write_changecounter(pList);
+ rc = sqlite3WalFrames(pPager->pWal,
+ pPager->pageSize, pList, nTruncate, isCommit, pPager->walSyncFlags
+ );
+ if( rc==SQLITE_OK && pPager->pBackup ){
+ for(p=pList; p; p=p->pDirty){
+ sqlite3BackupUpdate(pPager->pBackup, p->pgno, (u8 *)p->pData);
+ }
+ }
+
+#ifdef SQLITE_CHECK_PAGES
+ pList = sqlite3PcacheDirtyList(pPager->pPCache);
+ for(p=pList; p; p=p->pDirty){
+ pager_set_pagehash(p);
+ }
+#endif
+
+ return rc;
+}
+
+/*
+** Begin a read transaction on the WAL.
+**
+** This routine used to be called "pagerOpenSnapshot()" because it essentially
+** makes a snapshot of the database at the current point in time and preserves
+** that snapshot for use by the reader in spite of concurrently changes by
+** other writers or checkpointers.
+*/
+static int pagerBeginReadTransaction(Pager *pPager){
+ int rc; /* Return code */
+ int changed = 0; /* True if cache must be reset */
+
+ assert( pagerUseWal(pPager) );
+ assert( pPager->eState==PAGER_OPEN || pPager->eState==PAGER_READER );
+
+ /* sqlite3WalEndReadTransaction() was not called for the previous
+ ** transaction in locking_mode=EXCLUSIVE. So call it now. If we
+ ** are in locking_mode=NORMAL and EndRead() was previously called,
+ ** the duplicate call is harmless.
+ */
+ sqlite3WalEndReadTransaction(pPager->pWal);
+
+ rc = sqlite3WalBeginReadTransaction(pPager->pWal, &changed);
+ if( rc!=SQLITE_OK || changed ){
+ pager_reset(pPager);
+ if( USEFETCH(pPager) ) sqlite3OsUnfetch(pPager->fd, 0, 0);
+ }
+
+ return rc;
+}
+#endif
+
+/*
+** This function is called as part of the transition from PAGER_OPEN
+** to PAGER_READER state to determine the size of the database file
+** in pages (assuming the page size currently stored in Pager.pageSize).
+**
+** If no error occurs, SQLITE_OK is returned and the size of the database
+** in pages is stored in *pnPage. Otherwise, an error code (perhaps
+** SQLITE_IOERR_FSTAT) is returned and *pnPage is left unmodified.
+*/
+static int pagerPagecount(Pager *pPager, Pgno *pnPage){
+ Pgno nPage; /* Value to return via *pnPage */
+
+ /* Query the WAL sub-system for the database size. The WalDbsize()
+ ** function returns zero if the WAL is not open (i.e. Pager.pWal==0), or
+ ** if the database size is not available. The database size is not
+ ** available from the WAL sub-system if the log file is empty or
+ ** contains no valid committed transactions.
+ */
+ assert( pPager->eState==PAGER_OPEN );
+ assert( pPager->eLock>=SHARED_LOCK );
+ assert( isOpen(pPager->fd) );
+ assert( pPager->tempFile==0 );
+ nPage = sqlite3WalDbsize(pPager->pWal);
+
+ /* If the number of pages in the database is not available from the
+ ** WAL sub-system, determine the page count based on the size of
+ ** the database file. If the size of the database file is not an
+ ** integer multiple of the page-size, round up the result.
+ */
+ if( nPage==0 && ALWAYS(isOpen(pPager->fd)) ){
+ i64 n = 0; /* Size of db file in bytes */
+ int rc = sqlite3OsFileSize(pPager->fd, &n);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ nPage = (Pgno)((n+pPager->pageSize-1) / pPager->pageSize);
+ }
+
+ /* If the current number of pages in the file is greater than the
+ ** configured maximum pager number, increase the allowed limit so
+ ** that the file can be read.
+ */
+ if( nPage>pPager->mxPgno ){
+ pPager->mxPgno = (Pgno)nPage;
+ }
+
+ *pnPage = nPage;
+ return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_WAL
+/*
+** Check if the *-wal file that corresponds to the database opened by pPager
+** exists if the database is not empy, or verify that the *-wal file does
+** not exist (by deleting it) if the database file is empty.
+**
+** If the database is not empty and the *-wal file exists, open the pager
+** in WAL mode. If the database is empty or if no *-wal file exists and
+** if no error occurs, make sure Pager.journalMode is not set to
+** PAGER_JOURNALMODE_WAL.
+**
+** Return SQLITE_OK or an error code.
+**
+** The caller must hold a SHARED lock on the database file to call this
+** function. Because an EXCLUSIVE lock on the db file is required to delete
+** a WAL on a none-empty database, this ensures there is no race condition
+** between the xAccess() below and an xDelete() being executed by some
+** other connection.
+*/
+static int pagerOpenWalIfPresent(Pager *pPager){
+ int rc = SQLITE_OK;
+ assert( pPager->eState==PAGER_OPEN );
+ assert( pPager->eLock>=SHARED_LOCK );
+
+ if( !pPager->tempFile ){
+ int isWal; /* True if WAL file exists */
+ rc = sqlite3OsAccess(
+ pPager->pVfs, pPager->zWal, SQLITE_ACCESS_EXISTS, &isWal
+ );
+ if( rc==SQLITE_OK ){
+ if( isWal ){
+ Pgno nPage; /* Size of the database file */
+
+ rc = pagerPagecount(pPager, &nPage);
+ if( rc ) return rc;
+ if( nPage==0 ){
+ rc = sqlite3OsDelete(pPager->pVfs, pPager->zWal, 0);
+ }else{
+ testcase( sqlite3PcachePagecount(pPager->pPCache)==0 );
+ rc = sqlite3PagerOpenWal(pPager, 0);
+ }
+ }else if( pPager->journalMode==PAGER_JOURNALMODE_WAL ){
+ pPager->journalMode = PAGER_JOURNALMODE_DELETE;
+ }
+ }
+ }
+ return rc;
+}
+#endif
+
+/*
+** Playback savepoint pSavepoint. Or, if pSavepoint==NULL, then playback
+** the entire master journal file. The case pSavepoint==NULL occurs when
+** a ROLLBACK TO command is invoked on a SAVEPOINT that is a transaction
+** savepoint.
+**
+** When pSavepoint is not NULL (meaning a non-transaction savepoint is
+** being rolled back), then the rollback consists of up to three stages,
+** performed in the order specified:
+**
+** * Pages are played back from the main journal starting at byte
+** offset PagerSavepoint.iOffset and continuing to
+** PagerSavepoint.iHdrOffset, or to the end of the main journal
+** file if PagerSavepoint.iHdrOffset is zero.
+**
+** * If PagerSavepoint.iHdrOffset is not zero, then pages are played
+** back starting from the journal header immediately following
+** PagerSavepoint.iHdrOffset to the end of the main journal file.
+**
+** * Pages are then played back from the sub-journal file, starting
+** with the PagerSavepoint.iSubRec and continuing to the end of
+** the journal file.
+**
+** Throughout the rollback process, each time a page is rolled back, the
+** corresponding bit is set in a bitvec structure (variable pDone in the
+** implementation below). This is used to ensure that a page is only
+** rolled back the first time it is encountered in either journal.
+**
+** If pSavepoint is NULL, then pages are only played back from the main
+** journal file. There is no need for a bitvec in this case.
+**
+** In either case, before playback commences the Pager.dbSize variable
+** is reset to the value that it held at the start of the savepoint
+** (or transaction). No page with a page-number greater than this value
+** is played back. If one is encountered it is simply skipped.
+*/
+static int pagerPlaybackSavepoint(Pager *pPager, PagerSavepoint *pSavepoint){
+ i64 szJ; /* Effective size of the main journal */
+ i64 iHdrOff; /* End of first segment of main-journal records */
+ int rc = SQLITE_OK; /* Return code */
+ Bitvec *pDone = 0; /* Bitvec to ensure pages played back only once */
+
+ assert( pPager->eState!=PAGER_ERROR );
+ assert( pPager->eState>=PAGER_WRITER_LOCKED );
+
+ /* Allocate a bitvec to use to store the set of pages rolled back */
+ if( pSavepoint ){
+ pDone = sqlite3BitvecCreate(pSavepoint->nOrig);
+ if( !pDone ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ }
+
+ /* Set the database size back to the value it was before the savepoint
+ ** being reverted was opened.
+ */
+ pPager->dbSize = pSavepoint ? pSavepoint->nOrig : pPager->dbOrigSize;
+ pPager->changeCountDone = pPager->tempFile;
+
+ if( !pSavepoint && pagerUseWal(pPager) ){
+ return pagerRollbackWal(pPager);
+ }
+
+ /* Use pPager->journalOff as the effective size of the main rollback
+ ** journal. The actual file might be larger than this in
+ ** PAGER_JOURNALMODE_TRUNCATE or PAGER_JOURNALMODE_PERSIST. But anything
+ ** past pPager->journalOff is off-limits to us.
+ */
+ szJ = pPager->journalOff;
+ assert( pagerUseWal(pPager)==0 || szJ==0 );
+
+ /* Begin by rolling back records from the main journal starting at
+ ** PagerSavepoint.iOffset and continuing to the next journal header.
+ ** There might be records in the main journal that have a page number
+ ** greater than the current database size (pPager->dbSize) but those
+ ** will be skipped automatically. Pages are added to pDone as they
+ ** are played back.
+ */
+ if( pSavepoint && !pagerUseWal(pPager) ){
+ iHdrOff = pSavepoint->iHdrOffset ? pSavepoint->iHdrOffset : szJ;
+ pPager->journalOff = pSavepoint->iOffset;
+ while( rc==SQLITE_OK && pPager->journalOffjournalOff, pDone, 1, 1);
+ }
+ assert( rc!=SQLITE_DONE );
+ }else{
+ pPager->journalOff = 0;
+ }
+
+ /* Continue rolling back records out of the main journal starting at
+ ** the first journal header seen and continuing until the effective end
+ ** of the main journal file. Continue to skip out-of-range pages and
+ ** continue adding pages rolled back to pDone.
+ */
+ while( rc==SQLITE_OK && pPager->journalOffjournalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff"
+ ** test is related to ticket #2565. See the discussion in the
+ ** pager_playback() function for additional information.
+ */
+ if( nJRec==0
+ && pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff
+ ){
+ nJRec = (u32)((szJ - pPager->journalOff)/JOURNAL_PG_SZ(pPager));
+ }
+ for(ii=0; rc==SQLITE_OK && iijournalOffjournalOff, pDone, 1, 1);
+ }
+ assert( rc!=SQLITE_DONE );
+ }
+ assert( rc!=SQLITE_OK || pPager->journalOff>=szJ );
+
+ /* Finally, rollback pages from the sub-journal. Page that were
+ ** previously rolled back out of the main journal (and are hence in pDone)
+ ** will be skipped. Out-of-range pages are also skipped.
+ */
+ if( pSavepoint ){
+ u32 ii; /* Loop counter */
+ i64 offset = (i64)pSavepoint->iSubRec*(4+pPager->pageSize);
+
+ if( pagerUseWal(pPager) ){
+ rc = sqlite3WalSavepointUndo(pPager->pWal, pSavepoint->aWalData);
+ }
+ for(ii=pSavepoint->iSubRec; rc==SQLITE_OK && iinSubRec; ii++){
+ assert( offset==(i64)ii*(4+pPager->pageSize) );
+ rc = pager_playback_one_page(pPager, &offset, pDone, 0, 1);
+ }
+ assert( rc!=SQLITE_DONE );
+ }
+
+ sqlite3BitvecDestroy(pDone);
+ if( rc==SQLITE_OK ){
+ pPager->journalOff = szJ;
+ }
+
+ return rc;
+}
+
+/*
+** Change the maximum number of in-memory pages that are allowed
+** before attempting to recycle clean and unused pages.
+*/
+SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager *pPager, int mxPage){
+ sqlite3PcacheSetCachesize(pPager->pPCache, mxPage);
+}
+
+/*
+** Change the maximum number of in-memory pages that are allowed
+** before attempting to spill pages to journal.
+*/
+SQLITE_PRIVATE int sqlite3PagerSetSpillsize(Pager *pPager, int mxPage){
+ return sqlite3PcacheSetSpillsize(pPager->pPCache, mxPage);
+}
+
+/*
+** Invoke SQLITE_FCNTL_MMAP_SIZE based on the current value of szMmap.
+*/
+static void pagerFixMaplimit(Pager *pPager){
+#if SQLITE_MAX_MMAP_SIZE>0
+ sqlite3_file *fd = pPager->fd;
+ if( isOpen(fd) && fd->pMethods->iVersion>=3 ){
+ sqlite3_int64 sz;
+ sz = pPager->szMmap;
+ pPager->bUseFetch = (sz>0);
+ setGetterMethod(pPager);
+ sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_MMAP_SIZE, &sz);
+ }
+#endif
+}
+
+/*
+** Change the maximum size of any memory mapping made of the database file.
+*/
+SQLITE_PRIVATE void sqlite3PagerSetMmapLimit(Pager *pPager, sqlite3_int64 szMmap){
+ pPager->szMmap = szMmap;
+ pagerFixMaplimit(pPager);
+}
+
+/*
+** Free as much memory as possible from the pager.
+*/
+SQLITE_PRIVATE void sqlite3PagerShrink(Pager *pPager){
+ sqlite3PcacheShrink(pPager->pPCache);
+}
+
+/*
+** Adjust settings of the pager to those specified in the pgFlags parameter.
+**
+** The "level" in pgFlags & PAGER_SYNCHRONOUS_MASK sets the robustness
+** of the database to damage due to OS crashes or power failures by
+** changing the number of syncs()s when writing the journals.
+** There are four levels:
+**
+** OFF sqlite3OsSync() is never called. This is the default
+** for temporary and transient files.
+**
+** NORMAL The journal is synced once before writes begin on the
+** database. This is normally adequate protection, but
+** it is theoretically possible, though very unlikely,
+** that an inopertune power failure could leave the journal
+** in a state which would cause damage to the database
+** when it is rolled back.
+**
+** FULL The journal is synced twice before writes begin on the
+** database (with some additional information - the nRec field
+** of the journal header - being written in between the two
+** syncs). If we assume that writing a
+** single disk sector is atomic, then this mode provides
+** assurance that the journal will not be corrupted to the
+** point of causing damage to the database during rollback.
+**
+** EXTRA This is like FULL except that is also syncs the directory
+** that contains the rollback journal after the rollback
+** journal is unlinked.
+**
+** The above is for a rollback-journal mode. For WAL mode, OFF continues
+** to mean that no syncs ever occur. NORMAL means that the WAL is synced
+** prior to the start of checkpoint and that the database file is synced
+** at the conclusion of the checkpoint if the entire content of the WAL
+** was written back into the database. But no sync operations occur for
+** an ordinary commit in NORMAL mode with WAL. FULL means that the WAL
+** file is synced following each commit operation, in addition to the
+** syncs associated with NORMAL. There is no difference between FULL
+** and EXTRA for WAL mode.
+**
+** Do not confuse synchronous=FULL with SQLITE_SYNC_FULL. The
+** SQLITE_SYNC_FULL macro means to use the MacOSX-style full-fsync
+** using fcntl(F_FULLFSYNC). SQLITE_SYNC_NORMAL means to do an
+** ordinary fsync() call. There is no difference between SQLITE_SYNC_FULL
+** and SQLITE_SYNC_NORMAL on platforms other than MacOSX. But the
+** synchronous=FULL versus synchronous=NORMAL setting determines when
+** the xSync primitive is called and is relevant to all platforms.
+**
+** Numeric values associated with these states are OFF==1, NORMAL=2,
+** and FULL=3.
+*/
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+SQLITE_PRIVATE void sqlite3PagerSetFlags(
+ Pager *pPager, /* The pager to set safety level for */
+ unsigned pgFlags /* Various flags */
+){
+ unsigned level = pgFlags & PAGER_SYNCHRONOUS_MASK;
+ if( pPager->tempFile ){
+ pPager->noSync = 1;
+ pPager->fullSync = 0;
+ pPager->extraSync = 0;
+ }else{
+ pPager->noSync = level==PAGER_SYNCHRONOUS_OFF ?1:0;
+ pPager->fullSync = level>=PAGER_SYNCHRONOUS_FULL ?1:0;
+ pPager->extraSync = level==PAGER_SYNCHRONOUS_EXTRA ?1:0;
+ }
+ if( pPager->noSync ){
+ pPager->syncFlags = 0;
+ }else if( pgFlags & PAGER_FULLFSYNC ){
+ pPager->syncFlags = SQLITE_SYNC_FULL;
+ }else{
+ pPager->syncFlags = SQLITE_SYNC_NORMAL;
+ }
+ pPager->walSyncFlags = (pPager->syncFlags<<2);
+ if( pPager->fullSync ){
+ pPager->walSyncFlags |= pPager->syncFlags;
+ }
+ if( (pgFlags & PAGER_CKPT_FULLFSYNC) && !pPager->noSync ){
+ pPager->walSyncFlags |= (SQLITE_SYNC_FULL<<2);
+ }
+ if( pgFlags & PAGER_CACHESPILL ){
+ pPager->doNotSpill &= ~SPILLFLAG_OFF;
+ }else{
+ pPager->doNotSpill |= SPILLFLAG_OFF;
+ }
+}
+#endif
+
+/*
+** The following global variable is incremented whenever the library
+** attempts to open a temporary file. This information is used for
+** testing and analysis only.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_opentemp_count = 0;
+#endif
+
+/*
+** Open a temporary file.
+**
+** Write the file descriptor into *pFile. Return SQLITE_OK on success
+** or some other error code if we fail. The OS will automatically
+** delete the temporary file when it is closed.
+**
+** The flags passed to the VFS layer xOpen() call are those specified
+** by parameter vfsFlags ORed with the following:
+**
+** SQLITE_OPEN_READWRITE
+** SQLITE_OPEN_CREATE
+** SQLITE_OPEN_EXCLUSIVE
+** SQLITE_OPEN_DELETEONCLOSE
+*/
+static int pagerOpentemp(
+ Pager *pPager, /* The pager object */
+ sqlite3_file *pFile, /* Write the file descriptor here */
+ int vfsFlags /* Flags passed through to the VFS */
+){
+ int rc; /* Return code */
+
+#ifdef SQLITE_TEST
+ sqlite3_opentemp_count++; /* Used for testing and analysis only */
+#endif
+
+ vfsFlags |= SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE |
+ SQLITE_OPEN_EXCLUSIVE | SQLITE_OPEN_DELETEONCLOSE;
+ rc = sqlite3OsOpen(pPager->pVfs, 0, pFile, vfsFlags, 0);
+ assert( rc!=SQLITE_OK || isOpen(pFile) );
+ return rc;
+}
+
+/*
+** Set the busy handler function.
+**
+** The pager invokes the busy-handler if sqlite3OsLock() returns
+** SQLITE_BUSY when trying to upgrade from no-lock to a SHARED lock,
+** or when trying to upgrade from a RESERVED lock to an EXCLUSIVE
+** lock. It does *not* invoke the busy handler when upgrading from
+** SHARED to RESERVED, or when upgrading from SHARED to EXCLUSIVE
+** (which occurs during hot-journal rollback). Summary:
+**
+** Transition | Invokes xBusyHandler
+** --------------------------------------------------------
+** NO_LOCK -> SHARED_LOCK | Yes
+** SHARED_LOCK -> RESERVED_LOCK | No
+** SHARED_LOCK -> EXCLUSIVE_LOCK | No
+** RESERVED_LOCK -> EXCLUSIVE_LOCK | Yes
+**
+** If the busy-handler callback returns non-zero, the lock is
+** retried. If it returns zero, then the SQLITE_BUSY error is
+** returned to the caller of the pager API function.
+*/
+SQLITE_PRIVATE void sqlite3PagerSetBusyHandler(
+ Pager *pPager, /* Pager object */
+ int (*xBusyHandler)(void *), /* Pointer to busy-handler function */
+ void *pBusyHandlerArg /* Argument to pass to xBusyHandler */
+){
+ void **ap;
+ pPager->xBusyHandler = xBusyHandler;
+ pPager->pBusyHandlerArg = pBusyHandlerArg;
+ ap = (void **)&pPager->xBusyHandler;
+ assert( ((int(*)(void *))(ap[0]))==xBusyHandler );
+ assert( ap[1]==pBusyHandlerArg );
+ sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_BUSYHANDLER, (void *)ap);
+}
+
+/*
+** Change the page size used by the Pager object. The new page size
+** is passed in *pPageSize.
+**
+** If the pager is in the error state when this function is called, it
+** is a no-op. The value returned is the error state error code (i.e.
+** one of SQLITE_IOERR, an SQLITE_IOERR_xxx sub-code or SQLITE_FULL).
+**
+** Otherwise, if all of the following are true:
+**
+** * the new page size (value of *pPageSize) is valid (a power
+** of two between 512 and SQLITE_MAX_PAGE_SIZE, inclusive), and
+**
+** * there are no outstanding page references, and
+**
+** * the database is either not an in-memory database or it is
+** an in-memory database that currently consists of zero pages.
+**
+** then the pager object page size is set to *pPageSize.
+**
+** If the page size is changed, then this function uses sqlite3PagerMalloc()
+** to obtain a new Pager.pTmpSpace buffer. If this allocation attempt
+** fails, SQLITE_NOMEM is returned and the page size remains unchanged.
+** In all other cases, SQLITE_OK is returned.
+**
+** If the page size is not changed, either because one of the enumerated
+** conditions above is not true, the pager was in error state when this
+** function was called, or because the memory allocation attempt failed,
+** then *pPageSize is set to the old, retained page size before returning.
+*/
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u32 *pPageSize, int nReserve){
+ int rc = SQLITE_OK;
+
+ /* It is not possible to do a full assert_pager_state() here, as this
+ ** function may be called from within PagerOpen(), before the state
+ ** of the Pager object is internally consistent.
+ **
+ ** At one point this function returned an error if the pager was in
+ ** PAGER_ERROR state. But since PAGER_ERROR state guarantees that
+ ** there is at least one outstanding page reference, this function
+ ** is a no-op for that case anyhow.
+ */
+
+ u32 pageSize = *pPageSize;
+ assert( pageSize==0 || (pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE) );
+ if( (pPager->memDb==0 || pPager->dbSize==0)
+ && sqlite3PcacheRefCount(pPager->pPCache)==0
+ && pageSize && pageSize!=(u32)pPager->pageSize
+ ){
+ char *pNew = NULL; /* New temp space */
+ i64 nByte = 0;
+
+ if( pPager->eState>PAGER_OPEN && isOpen(pPager->fd) ){
+ rc = sqlite3OsFileSize(pPager->fd, &nByte);
+ }
+ if( rc==SQLITE_OK ){
+ pNew = (char *)sqlite3PageMalloc(pageSize);
+ if( !pNew ) rc = SQLITE_NOMEM_BKPT;
+ }
+
+ if( rc==SQLITE_OK ){
+ pager_reset(pPager);
+ rc = sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
+ }
+ if( rc==SQLITE_OK ){
+ sqlite3PageFree(pPager->pTmpSpace);
+ pPager->pTmpSpace = pNew;
+ pPager->dbSize = (Pgno)((nByte+pageSize-1)/pageSize);
+ pPager->pageSize = pageSize;
+ }else{
+ sqlite3PageFree(pNew);
+ }
+ }
+
+ *pPageSize = pPager->pageSize;
+ if( rc==SQLITE_OK ){
+ if( nReserve<0 ) nReserve = pPager->nReserve;
+ assert( nReserve>=0 && nReserve<1000 );
+ pPager->nReserve = (i16)nReserve;
+ pagerReportSize(pPager);
+ pagerFixMaplimit(pPager);
+ }
+ return rc;
+}
+
+/*
+** Return a pointer to the "temporary page" buffer held internally
+** by the pager. This is a buffer that is big enough to hold the
+** entire content of a database page. This buffer is used internally
+** during rollback and will be overwritten whenever a rollback
+** occurs. But other modules are free to use it too, as long as
+** no rollbacks are happening.
+*/
+SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager *pPager){
+ return pPager->pTmpSpace;
+}
+
+/*
+** Attempt to set the maximum database page count if mxPage is positive.
+** Make no changes if mxPage is zero or negative. And never reduce the
+** maximum page count below the current size of the database.
+**
+** Regardless of mxPage, return the current maximum page count.
+*/
+SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager *pPager, int mxPage){
+ if( mxPage>0 ){
+ pPager->mxPgno = mxPage;
+ }
+ assert( pPager->eState!=PAGER_OPEN ); /* Called only by OP_MaxPgcnt */
+ assert( pPager->mxPgno>=pPager->dbSize ); /* OP_MaxPgcnt enforces this */
+ return pPager->mxPgno;
+}
+
+/*
+** The following set of routines are used to disable the simulated
+** I/O error mechanism. These routines are used to avoid simulated
+** errors in places where we do not care about errors.
+**
+** Unless -DSQLITE_TEST=1 is used, these routines are all no-ops
+** and generate no code.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API extern int sqlite3_io_error_pending;
+SQLITE_API extern int sqlite3_io_error_hit;
+static int saved_cnt;
+void disable_simulated_io_errors(void){
+ saved_cnt = sqlite3_io_error_pending;
+ sqlite3_io_error_pending = -1;
+}
+void enable_simulated_io_errors(void){
+ sqlite3_io_error_pending = saved_cnt;
+}
+#else
+# define disable_simulated_io_errors()
+# define enable_simulated_io_errors()
+#endif
+
+/*
+** Read the first N bytes from the beginning of the file into memory
+** that pDest points to.
+**
+** If the pager was opened on a transient file (zFilename==""), or
+** opened on a file less than N bytes in size, the output buffer is
+** zeroed and SQLITE_OK returned. The rationale for this is that this
+** function is used to read database headers, and a new transient or
+** zero sized database has a header than consists entirely of zeroes.
+**
+** If any IO error apart from SQLITE_IOERR_SHORT_READ is encountered,
+** the error code is returned to the caller and the contents of the
+** output buffer undefined.
+*/
+SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager *pPager, int N, unsigned char *pDest){
+ int rc = SQLITE_OK;
+ memset(pDest, 0, N);
+ assert( isOpen(pPager->fd) || pPager->tempFile );
+
+ /* This routine is only called by btree immediately after creating
+ ** the Pager object. There has not been an opportunity to transition
+ ** to WAL mode yet.
+ */
+ assert( !pagerUseWal(pPager) );
+
+ if( isOpen(pPager->fd) ){
+ IOTRACE(("DBHDR %p 0 %d\n", pPager, N))
+ rc = sqlite3OsRead(pPager->fd, pDest, N, 0);
+ if( rc==SQLITE_IOERR_SHORT_READ ){
+ rc = SQLITE_OK;
+ }
+ }
+ return rc;
+}
+
+/*
+** This function may only be called when a read-transaction is open on
+** the pager. It returns the total number of pages in the database.
+**
+** However, if the file is between 1 and bytes in size, then
+** this is considered a 1 page file.
+*/
+SQLITE_PRIVATE void sqlite3PagerPagecount(Pager *pPager, int *pnPage){
+ assert( pPager->eState>=PAGER_READER );
+ assert( pPager->eState!=PAGER_WRITER_FINISHED );
+ *pnPage = (int)pPager->dbSize;
+}
+
+
+/*
+** Try to obtain a lock of type locktype on the database file. If
+** a similar or greater lock is already held, this function is a no-op
+** (returning SQLITE_OK immediately).
+**
+** Otherwise, attempt to obtain the lock using sqlite3OsLock(). Invoke
+** the busy callback if the lock is currently not available. Repeat
+** until the busy callback returns false or until the attempt to
+** obtain the lock succeeds.
+**
+** Return SQLITE_OK on success and an error code if we cannot obtain
+** the lock. If the lock is obtained successfully, set the Pager.state
+** variable to locktype before returning.
+*/
+static int pager_wait_on_lock(Pager *pPager, int locktype){
+ int rc; /* Return code */
+
+ /* Check that this is either a no-op (because the requested lock is
+ ** already held), or one of the transitions that the busy-handler
+ ** may be invoked during, according to the comment above
+ ** sqlite3PagerSetBusyhandler().
+ */
+ assert( (pPager->eLock>=locktype)
+ || (pPager->eLock==NO_LOCK && locktype==SHARED_LOCK)
+ || (pPager->eLock==RESERVED_LOCK && locktype==EXCLUSIVE_LOCK)
+ );
+
+ do {
+ rc = pagerLockDb(pPager, locktype);
+ }while( rc==SQLITE_BUSY && pPager->xBusyHandler(pPager->pBusyHandlerArg) );
+ return rc;
+}
+
+/*
+** Function assertTruncateConstraint(pPager) checks that one of the
+** following is true for all dirty pages currently in the page-cache:
+**
+** a) The page number is less than or equal to the size of the
+** current database image, in pages, OR
+**
+** b) if the page content were written at this time, it would not
+** be necessary to write the current content out to the sub-journal
+** (as determined by function subjRequiresPage()).
+**
+** If the condition asserted by this function were not true, and the
+** dirty page were to be discarded from the cache via the pagerStress()
+** routine, pagerStress() would not write the current page content to
+** the database file. If a savepoint transaction were rolled back after
+** this happened, the correct behavior would be to restore the current
+** content of the page. However, since this content is not present in either
+** the database file or the portion of the rollback journal and
+** sub-journal rolled back the content could not be restored and the
+** database image would become corrupt. It is therefore fortunate that
+** this circumstance cannot arise.
+*/
+#if defined(SQLITE_DEBUG)
+static void assertTruncateConstraintCb(PgHdr *pPg){
+ assert( pPg->flags&PGHDR_DIRTY );
+ assert( !subjRequiresPage(pPg) || pPg->pgno<=pPg->pPager->dbSize );
+}
+static void assertTruncateConstraint(Pager *pPager){
+ sqlite3PcacheIterateDirty(pPager->pPCache, assertTruncateConstraintCb);
+}
+#else
+# define assertTruncateConstraint(pPager)
+#endif
+
+/*
+** Truncate the in-memory database file image to nPage pages. This
+** function does not actually modify the database file on disk. It
+** just sets the internal state of the pager object so that the
+** truncation will be done when the current transaction is committed.
+**
+** This function is only called right before committing a transaction.
+** Once this function has been called, the transaction must either be
+** rolled back or committed. It is not safe to call this function and
+** then continue writing to the database.
+*/
+SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager *pPager, Pgno nPage){
+ assert( pPager->dbSize>=nPage );
+ assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
+ pPager->dbSize = nPage;
+
+ /* At one point the code here called assertTruncateConstraint() to
+ ** ensure that all pages being truncated away by this operation are,
+ ** if one or more savepoints are open, present in the savepoint
+ ** journal so that they can be restored if the savepoint is rolled
+ ** back. This is no longer necessary as this function is now only
+ ** called right before committing a transaction. So although the
+ ** Pager object may still have open savepoints (Pager.nSavepoint!=0),
+ ** they cannot be rolled back. So the assertTruncateConstraint() call
+ ** is no longer correct. */
+}
+
+
+/*
+** This function is called before attempting a hot-journal rollback. It
+** syncs the journal file to disk, then sets pPager->journalHdr to the
+** size of the journal file so that the pager_playback() routine knows
+** that the entire journal file has been synced.
+**
+** Syncing a hot-journal to disk before attempting to roll it back ensures
+** that if a power-failure occurs during the rollback, the process that
+** attempts rollback following system recovery sees the same journal
+** content as this process.
+**
+** If everything goes as planned, SQLITE_OK is returned. Otherwise,
+** an SQLite error code.
+*/
+static int pagerSyncHotJournal(Pager *pPager){
+ int rc = SQLITE_OK;
+ if( !pPager->noSync ){
+ rc = sqlite3OsSync(pPager->jfd, SQLITE_SYNC_NORMAL);
+ }
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsFileSize(pPager->jfd, &pPager->journalHdr);
+ }
+ return rc;
+}
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/*
+** Obtain a reference to a memory mapped page object for page number pgno.
+** The new object will use the pointer pData, obtained from xFetch().
+** If successful, set *ppPage to point to the new page reference
+** and return SQLITE_OK. Otherwise, return an SQLite error code and set
+** *ppPage to zero.
+**
+** Page references obtained by calling this function should be released
+** by calling pagerReleaseMapPage().
+*/
+static int pagerAcquireMapPage(
+ Pager *pPager, /* Pager object */
+ Pgno pgno, /* Page number */
+ void *pData, /* xFetch()'d data for this page */
+ PgHdr **ppPage /* OUT: Acquired page object */
+){
+ PgHdr *p; /* Memory mapped page to return */
+
+ if( pPager->pMmapFreelist ){
+ *ppPage = p = pPager->pMmapFreelist;
+ pPager->pMmapFreelist = p->pDirty;
+ p->pDirty = 0;
+ assert( pPager->nExtra>=8 );
+ memset(p->pExtra, 0, 8);
+ }else{
+ *ppPage = p = (PgHdr *)sqlite3MallocZero(sizeof(PgHdr) + pPager->nExtra);
+ if( p==0 ){
+ sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1) * pPager->pageSize, pData);
+ return SQLITE_NOMEM_BKPT;
+ }
+ p->pExtra = (void *)&p[1];
+ p->flags = PGHDR_MMAP;
+ p->nRef = 1;
+ p->pPager = pPager;
+ }
+
+ assert( p->pExtra==(void *)&p[1] );
+ assert( p->pPage==0 );
+ assert( p->flags==PGHDR_MMAP );
+ assert( p->pPager==pPager );
+ assert( p->nRef==1 );
+
+ p->pgno = pgno;
+ p->pData = pData;
+ pPager->nMmapOut++;
+
+ return SQLITE_OK;
+}
+#endif
+
+/*
+** Release a reference to page pPg. pPg must have been returned by an
+** earlier call to pagerAcquireMapPage().
+*/
+static void pagerReleaseMapPage(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ pPager->nMmapOut--;
+ pPg->pDirty = pPager->pMmapFreelist;
+ pPager->pMmapFreelist = pPg;
+
+ assert( pPager->fd->pMethods->iVersion>=3 );
+ sqlite3OsUnfetch(pPager->fd, (i64)(pPg->pgno-1)*pPager->pageSize, pPg->pData);
+}
+
+/*
+** Free all PgHdr objects stored in the Pager.pMmapFreelist list.
+*/
+static void pagerFreeMapHdrs(Pager *pPager){
+ PgHdr *p;
+ PgHdr *pNext;
+ for(p=pPager->pMmapFreelist; p; p=pNext){
+ pNext = p->pDirty;
+ sqlite3_free(p);
+ }
+}
+
+/* Verify that the database file has not be deleted or renamed out from
+** under the pager. Return SQLITE_OK if the database is still where it ought
+** to be on disk. Return non-zero (SQLITE_READONLY_DBMOVED or some other error
+** code from sqlite3OsAccess()) if the database has gone missing.
+*/
+static int databaseIsUnmoved(Pager *pPager){
+ int bHasMoved = 0;
+ int rc;
+
+ if( pPager->tempFile ) return SQLITE_OK;
+ if( pPager->dbSize==0 ) return SQLITE_OK;
+ assert( pPager->zFilename && pPager->zFilename[0] );
+ rc = sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_HAS_MOVED, &bHasMoved);
+ if( rc==SQLITE_NOTFOUND ){
+ /* If the HAS_MOVED file-control is unimplemented, assume that the file
+ ** has not been moved. That is the historical behavior of SQLite: prior to
+ ** version 3.8.3, it never checked */
+ rc = SQLITE_OK;
+ }else if( rc==SQLITE_OK && bHasMoved ){
+ rc = SQLITE_READONLY_DBMOVED;
+ }
+ return rc;
+}
+
+
+/*
+** Shutdown the page cache. Free all memory and close all files.
+**
+** If a transaction was in progress when this routine is called, that
+** transaction is rolled back. All outstanding pages are invalidated
+** and their memory is freed. Any attempt to use a page associated
+** with this page cache after this function returns will likely
+** result in a coredump.
+**
+** This function always succeeds. If a transaction is active an attempt
+** is made to roll it back. If an error occurs during the rollback
+** a hot journal may be left in the filesystem but no error is returned
+** to the caller.
+*/
+SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager, sqlite3 *db){
+ u8 *pTmp = (u8*)pPager->pTmpSpace;
+ assert( db || pagerUseWal(pPager)==0 );
+ assert( assert_pager_state(pPager) );
+ disable_simulated_io_errors();
+ sqlite3BeginBenignMalloc();
+ pagerFreeMapHdrs(pPager);
+ /* pPager->errCode = 0; */
+ pPager->exclusiveMode = 0;
+#ifndef SQLITE_OMIT_WAL
+ {
+ u8 *a = 0;
+ assert( db || pPager->pWal==0 );
+ if( db && 0==(db->flags & SQLITE_NoCkptOnClose)
+ && SQLITE_OK==databaseIsUnmoved(pPager)
+ ){
+ a = pTmp;
+ }
+ sqlite3WalClose(pPager->pWal, db, pPager->walSyncFlags, pPager->pageSize,a);
+ pPager->pWal = 0;
+ }
+#endif
+ pager_reset(pPager);
+ if( MEMDB ){
+ pager_unlock(pPager);
+ }else{
+ /* If it is open, sync the journal file before calling UnlockAndRollback.
+ ** If this is not done, then an unsynced portion of the open journal
+ ** file may be played back into the database. If a power failure occurs
+ ** while this is happening, the database could become corrupt.
+ **
+ ** If an error occurs while trying to sync the journal, shift the pager
+ ** into the ERROR state. This causes UnlockAndRollback to unlock the
+ ** database and close the journal file without attempting to roll it
+ ** back or finalize it. The next database user will have to do hot-journal
+ ** rollback before accessing the database file.
+ */
+ if( isOpen(pPager->jfd) ){
+ pager_error(pPager, pagerSyncHotJournal(pPager));
+ }
+ pagerUnlockAndRollback(pPager);
+ }
+ sqlite3EndBenignMalloc();
+ enable_simulated_io_errors();
+ PAGERTRACE(("CLOSE %d\n", PAGERID(pPager)));
+ IOTRACE(("CLOSE %p\n", pPager))
+ sqlite3OsClose(pPager->jfd);
+ sqlite3OsClose(pPager->fd);
+ sqlite3PageFree(pTmp);
+ sqlite3PcacheClose(pPager->pPCache);
+
+#ifdef SQLITE_HAS_CODEC
+ if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
+#endif
+
+ assert( !pPager->aSavepoint && !pPager->pInJournal );
+ assert( !isOpen(pPager->jfd) && !isOpen(pPager->sjfd) );
+
+ sqlite3_free(pPager);
+ return SQLITE_OK;
+}
+
+#if !defined(NDEBUG) || defined(SQLITE_TEST)
+/*
+** Return the page number for page pPg.
+*/
+SQLITE_PRIVATE Pgno sqlite3PagerPagenumber(DbPage *pPg){
+ return pPg->pgno;
+}
+#endif
+
+/*
+** Increment the reference count for page pPg.
+*/
+SQLITE_PRIVATE void sqlite3PagerRef(DbPage *pPg){
+ sqlite3PcacheRef(pPg);
+}
+
+/*
+** Sync the journal. In other words, make sure all the pages that have
+** been written to the journal have actually reached the surface of the
+** disk and can be restored in the event of a hot-journal rollback.
+**
+** If the Pager.noSync flag is set, then this function is a no-op.
+** Otherwise, the actions required depend on the journal-mode and the
+** device characteristics of the file-system, as follows:
+**
+** * If the journal file is an in-memory journal file, no action need
+** be taken.
+**
+** * Otherwise, if the device does not support the SAFE_APPEND property,
+** then the nRec field of the most recently written journal header
+** is updated to contain the number of journal records that have
+** been written following it. If the pager is operating in full-sync
+** mode, then the journal file is synced before this field is updated.
+**
+** * If the device does not support the SEQUENTIAL property, then
+** journal file is synced.
+**
+** Or, in pseudo-code:
+**
+** if( NOT ){
+** if( NOT SAFE_APPEND ){
+** if( ) xSync();
+**
+** }
+** if( NOT SEQUENTIAL ) xSync();
+** }
+**
+** If successful, this routine clears the PGHDR_NEED_SYNC flag of every
+** page currently held in memory before returning SQLITE_OK. If an IO
+** error is encountered, then the IO error code is returned to the caller.
+*/
+static int syncJournal(Pager *pPager, int newHdr){
+ int rc; /* Return code */
+
+ assert( pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ );
+ assert( assert_pager_state(pPager) );
+ assert( !pagerUseWal(pPager) );
+
+ rc = sqlite3PagerExclusiveLock(pPager);
+ if( rc!=SQLITE_OK ) return rc;
+
+ if( !pPager->noSync ){
+ assert( !pPager->tempFile );
+ if( isOpen(pPager->jfd) && pPager->journalMode!=PAGER_JOURNALMODE_MEMORY ){
+ const int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
+ assert( isOpen(pPager->jfd) );
+
+ if( 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
+ /* This block deals with an obscure problem. If the last connection
+ ** that wrote to this database was operating in persistent-journal
+ ** mode, then the journal file may at this point actually be larger
+ ** than Pager.journalOff bytes. If the next thing in the journal
+ ** file happens to be a journal-header (written as part of the
+ ** previous connection's transaction), and a crash or power-failure
+ ** occurs after nRec is updated but before this connection writes
+ ** anything else to the journal file (or commits/rolls back its
+ ** transaction), then SQLite may become confused when doing the
+ ** hot-journal rollback following recovery. It may roll back all
+ ** of this connections data, then proceed to rolling back the old,
+ ** out-of-date data that follows it. Database corruption.
+ **
+ ** To work around this, if the journal file does appear to contain
+ ** a valid header following Pager.journalOff, then write a 0x00
+ ** byte to the start of it to prevent it from being recognized.
+ **
+ ** Variable iNextHdrOffset is set to the offset at which this
+ ** problematic header will occur, if it exists. aMagic is used
+ ** as a temporary buffer to inspect the first couple of bytes of
+ ** the potential journal header.
+ */
+ i64 iNextHdrOffset;
+ u8 aMagic[8];
+ u8 zHeader[sizeof(aJournalMagic)+4];
+
+ memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
+ put32bits(&zHeader[sizeof(aJournalMagic)], pPager->nRec);
+
+ iNextHdrOffset = journalHdrOffset(pPager);
+ rc = sqlite3OsRead(pPager->jfd, aMagic, 8, iNextHdrOffset);
+ if( rc==SQLITE_OK && 0==memcmp(aMagic, aJournalMagic, 8) ){
+ static const u8 zerobyte = 0;
+ rc = sqlite3OsWrite(pPager->jfd, &zerobyte, 1, iNextHdrOffset);
+ }
+ if( rc!=SQLITE_OK && rc!=SQLITE_IOERR_SHORT_READ ){
+ return rc;
+ }
+
+ /* Write the nRec value into the journal file header. If in
+ ** full-synchronous mode, sync the journal first. This ensures that
+ ** all data has really hit the disk before nRec is updated to mark
+ ** it as a candidate for rollback.
+ **
+ ** This is not required if the persistent media supports the
+ ** SAFE_APPEND property. Because in this case it is not possible
+ ** for garbage data to be appended to the file, the nRec field
+ ** is populated with 0xFFFFFFFF when the journal header is written
+ ** and never needs to be updated.
+ */
+ if( pPager->fullSync && 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
+ PAGERTRACE(("SYNC journal of %d\n", PAGERID(pPager)));
+ IOTRACE(("JSYNC %p\n", pPager))
+ rc = sqlite3OsSync(pPager->jfd, pPager->syncFlags);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ IOTRACE(("JHDR %p %lld\n", pPager, pPager->journalHdr));
+ rc = sqlite3OsWrite(
+ pPager->jfd, zHeader, sizeof(zHeader), pPager->journalHdr
+ );
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ if( 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
+ PAGERTRACE(("SYNC journal of %d\n", PAGERID(pPager)));
+ IOTRACE(("JSYNC %p\n", pPager))
+ rc = sqlite3OsSync(pPager->jfd, pPager->syncFlags|
+ (pPager->syncFlags==SQLITE_SYNC_FULL?SQLITE_SYNC_DATAONLY:0)
+ );
+ if( rc!=SQLITE_OK ) return rc;
+ }
+
+ pPager->journalHdr = pPager->journalOff;
+ if( newHdr && 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
+ pPager->nRec = 0;
+ rc = writeJournalHdr(pPager);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ }else{
+ pPager->journalHdr = pPager->journalOff;
+ }
+ }
+
+ /* Unless the pager is in noSync mode, the journal file was just
+ ** successfully synced. Either way, clear the PGHDR_NEED_SYNC flag on
+ ** all pages.
+ */
+ sqlite3PcacheClearSyncFlags(pPager->pPCache);
+ pPager->eState = PAGER_WRITER_DBMOD;
+ assert( assert_pager_state(pPager) );
+ return SQLITE_OK;
+}
+
+/*
+** The argument is the first in a linked list of dirty pages connected
+** by the PgHdr.pDirty pointer. This function writes each one of the
+** in-memory pages in the list to the database file. The argument may
+** be NULL, representing an empty list. In this case this function is
+** a no-op.
+**
+** The pager must hold at least a RESERVED lock when this function
+** is called. Before writing anything to the database file, this lock
+** is upgraded to an EXCLUSIVE lock. If the lock cannot be obtained,
+** SQLITE_BUSY is returned and no data is written to the database file.
+**
+** If the pager is a temp-file pager and the actual file-system file
+** is not yet open, it is created and opened before any data is
+** written out.
+**
+** Once the lock has been upgraded and, if necessary, the file opened,
+** the pages are written out to the database file in list order. Writing
+** a page is skipped if it meets either of the following criteria:
+**
+** * The page number is greater than Pager.dbSize, or
+** * The PGHDR_DONT_WRITE flag is set on the page.
+**
+** If writing out a page causes the database file to grow, Pager.dbFileSize
+** is updated accordingly. If page 1 is written out, then the value cached
+** in Pager.dbFileVers[] is updated to match the new value stored in
+** the database file.
+**
+** If everything is successful, SQLITE_OK is returned. If an IO error
+** occurs, an IO error code is returned. Or, if the EXCLUSIVE lock cannot
+** be obtained, SQLITE_BUSY is returned.
+*/
+static int pager_write_pagelist(Pager *pPager, PgHdr *pList){
+ int rc = SQLITE_OK; /* Return code */
+
+ /* This function is only called for rollback pagers in WRITER_DBMOD state. */
+ assert( !pagerUseWal(pPager) );
+ assert( pPager->tempFile || pPager->eState==PAGER_WRITER_DBMOD );
+ assert( pPager->eLock==EXCLUSIVE_LOCK );
+ assert( isOpen(pPager->fd) || pList->pDirty==0 );
+
+ /* If the file is a temp-file has not yet been opened, open it now. It
+ ** is not possible for rc to be other than SQLITE_OK if this branch
+ ** is taken, as pager_wait_on_lock() is a no-op for temp-files.
+ */
+ if( !isOpen(pPager->fd) ){
+ assert( pPager->tempFile && rc==SQLITE_OK );
+ rc = pagerOpentemp(pPager, pPager->fd, pPager->vfsFlags);
+ }
+
+ /* Before the first write, give the VFS a hint of what the final
+ ** file size will be.
+ */
+ assert( rc!=SQLITE_OK || isOpen(pPager->fd) );
+ if( rc==SQLITE_OK
+ && pPager->dbHintSizedbSize
+ && (pList->pDirty || pList->pgno>pPager->dbHintSize)
+ ){
+ sqlite3_int64 szFile = pPager->pageSize * (sqlite3_int64)pPager->dbSize;
+ sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_SIZE_HINT, &szFile);
+ pPager->dbHintSize = pPager->dbSize;
+ }
+
+ while( rc==SQLITE_OK && pList ){
+ Pgno pgno = pList->pgno;
+
+ /* If there are dirty pages in the page cache with page numbers greater
+ ** than Pager.dbSize, this means sqlite3PagerTruncateImage() was called to
+ ** make the file smaller (presumably by auto-vacuum code). Do not write
+ ** any such pages to the file.
+ **
+ ** Also, do not write out any page that has the PGHDR_DONT_WRITE flag
+ ** set (set by sqlite3PagerDontWrite()).
+ */
+ if( pgno<=pPager->dbSize && 0==(pList->flags&PGHDR_DONT_WRITE) ){
+ i64 offset = (pgno-1)*(i64)pPager->pageSize; /* Offset to write */
+ char *pData; /* Data to write */
+
+ assert( (pList->flags&PGHDR_NEED_SYNC)==0 );
+ if( pList->pgno==1 ) pager_write_changecounter(pList);
+
+ /* Encode the database */
+ CODEC2(pPager, pList->pData, pgno, 6, return SQLITE_NOMEM_BKPT, pData);
+
+ /* Write out the page data. */
+ rc = sqlite3OsWrite(pPager->fd, pData, pPager->pageSize, offset);
+
+ /* If page 1 was just written, update Pager.dbFileVers to match
+ ** the value now stored in the database file. If writing this
+ ** page caused the database file to grow, update dbFileSize.
+ */
+ if( pgno==1 ){
+ memcpy(&pPager->dbFileVers, &pData[24], sizeof(pPager->dbFileVers));
+ }
+ if( pgno>pPager->dbFileSize ){
+ pPager->dbFileSize = pgno;
+ }
+ pPager->aStat[PAGER_STAT_WRITE]++;
+
+ /* Update any backup objects copying the contents of this pager. */
+ sqlite3BackupUpdate(pPager->pBackup, pgno, (u8*)pList->pData);
+
+ PAGERTRACE(("STORE %d page %d hash(%08x)\n",
+ PAGERID(pPager), pgno, pager_pagehash(pList)));
+ IOTRACE(("PGOUT %p %d\n", pPager, pgno));
+ PAGER_INCR(sqlite3_pager_writedb_count);
+ }else{
+ PAGERTRACE(("NOSTORE %d page %d\n", PAGERID(pPager), pgno));
+ }
+ pager_set_pagehash(pList);
+ pList = pList->pDirty;
+ }
+
+ return rc;
+}
+
+/*
+** Ensure that the sub-journal file is open. If it is already open, this
+** function is a no-op.
+**
+** SQLITE_OK is returned if everything goes according to plan. An
+** SQLITE_IOERR_XXX error code is returned if a call to sqlite3OsOpen()
+** fails.
+*/
+static int openSubJournal(Pager *pPager){
+ int rc = SQLITE_OK;
+ if( !isOpen(pPager->sjfd) ){
+ const int flags = SQLITE_OPEN_SUBJOURNAL | SQLITE_OPEN_READWRITE
+ | SQLITE_OPEN_CREATE | SQLITE_OPEN_EXCLUSIVE
+ | SQLITE_OPEN_DELETEONCLOSE;
+ int nStmtSpill = sqlite3Config.nStmtSpill;
+ if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY || pPager->subjInMemory ){
+ nStmtSpill = -1;
+ }
+ rc = sqlite3JournalOpen(pPager->pVfs, 0, pPager->sjfd, flags, nStmtSpill);
+ }
+ return rc;
+}
+
+/*
+** Append a record of the current state of page pPg to the sub-journal.
+**
+** If successful, set the bit corresponding to pPg->pgno in the bitvecs
+** for all open savepoints before returning.
+**
+** This function returns SQLITE_OK if everything is successful, an IO
+** error code if the attempt to write to the sub-journal fails, or
+** SQLITE_NOMEM if a malloc fails while setting a bit in a savepoint
+** bitvec.
+*/
+static int subjournalPage(PgHdr *pPg){
+ int rc = SQLITE_OK;
+ Pager *pPager = pPg->pPager;
+ if( pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
+
+ /* Open the sub-journal, if it has not already been opened */
+ assert( pPager->useJournal );
+ assert( isOpen(pPager->jfd) || pagerUseWal(pPager) );
+ assert( isOpen(pPager->sjfd) || pPager->nSubRec==0 );
+ assert( pagerUseWal(pPager)
+ || pageInJournal(pPager, pPg)
+ || pPg->pgno>pPager->dbOrigSize
+ );
+ rc = openSubJournal(pPager);
+
+ /* If the sub-journal was opened successfully (or was already open),
+ ** write the journal record into the file. */
+ if( rc==SQLITE_OK ){
+ void *pData = pPg->pData;
+ i64 offset = (i64)pPager->nSubRec*(4+pPager->pageSize);
+ char *pData2;
+
+#if SQLITE_HAS_CODEC
+ if( !pPager->subjInMemory ){
+ CODEC2(pPager, pData, pPg->pgno, 7, return SQLITE_NOMEM_BKPT, pData2);
+ }else
+#endif
+ pData2 = pData;
+ PAGERTRACE(("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno));
+ rc = write32bits(pPager->sjfd, offset, pPg->pgno);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsWrite(pPager->sjfd, pData2, pPager->pageSize, offset+4);
+ }
+ }
+ }
+ if( rc==SQLITE_OK ){
+ pPager->nSubRec++;
+ assert( pPager->nSavepoint>0 );
+ rc = addToSavepointBitvecs(pPager, pPg->pgno);
+ }
+ return rc;
+}
+static int subjournalPageIfRequired(PgHdr *pPg){
+ if( subjRequiresPage(pPg) ){
+ return subjournalPage(pPg);
+ }else{
+ return SQLITE_OK;
+ }
+}
+
+/*
+** This function is called by the pcache layer when it has reached some
+** soft memory limit. The first argument is a pointer to a Pager object
+** (cast as a void*). The pager is always 'purgeable' (not an in-memory
+** database). The second argument is a reference to a page that is
+** currently dirty but has no outstanding references. The page
+** is always associated with the Pager object passed as the first
+** argument.
+**
+** The job of this function is to make pPg clean by writing its contents
+** out to the database file, if possible. This may involve syncing the
+** journal file.
+**
+** If successful, sqlite3PcacheMakeClean() is called on the page and
+** SQLITE_OK returned. If an IO error occurs while trying to make the
+** page clean, the IO error code is returned. If the page cannot be
+** made clean for some other reason, but no error occurs, then SQLITE_OK
+** is returned by sqlite3PcacheMakeClean() is not called.
+*/
+static int pagerStress(void *p, PgHdr *pPg){
+ Pager *pPager = (Pager *)p;
+ int rc = SQLITE_OK;
+
+ assert( pPg->pPager==pPager );
+ assert( pPg->flags&PGHDR_DIRTY );
+
+ /* The doNotSpill NOSYNC bit is set during times when doing a sync of
+ ** journal (and adding a new header) is not allowed. This occurs
+ ** during calls to sqlite3PagerWrite() while trying to journal multiple
+ ** pages belonging to the same sector.
+ **
+ ** The doNotSpill ROLLBACK and OFF bits inhibits all cache spilling
+ ** regardless of whether or not a sync is required. This is set during
+ ** a rollback or by user request, respectively.
+ **
+ ** Spilling is also prohibited when in an error state since that could
+ ** lead to database corruption. In the current implementation it
+ ** is impossible for sqlite3PcacheFetch() to be called with createFlag==3
+ ** while in the error state, hence it is impossible for this routine to
+ ** be called in the error state. Nevertheless, we include a NEVER()
+ ** test for the error state as a safeguard against future changes.
+ */
+ if( NEVER(pPager->errCode) ) return SQLITE_OK;
+ testcase( pPager->doNotSpill & SPILLFLAG_ROLLBACK );
+ testcase( pPager->doNotSpill & SPILLFLAG_OFF );
+ testcase( pPager->doNotSpill & SPILLFLAG_NOSYNC );
+ if( pPager->doNotSpill
+ && ((pPager->doNotSpill & (SPILLFLAG_ROLLBACK|SPILLFLAG_OFF))!=0
+ || (pPg->flags & PGHDR_NEED_SYNC)!=0)
+ ){
+ return SQLITE_OK;
+ }
+
+ pPager->aStat[PAGER_STAT_SPILL]++;
+ pPg->pDirty = 0;
+ if( pagerUseWal(pPager) ){
+ /* Write a single frame for this page to the log. */
+ rc = subjournalPageIfRequired(pPg);
+ if( rc==SQLITE_OK ){
+ rc = pagerWalFrames(pPager, pPg, 0, 0);
+ }
+ }else{
+
+#ifdef SQLITE_ENABLE_BATCH_ATOMIC_WRITE
+ if( pPager->tempFile==0 ){
+ rc = sqlite3JournalCreate(pPager->jfd);
+ if( rc!=SQLITE_OK ) return pager_error(pPager, rc);
+ }
+#endif
+
+ /* Sync the journal file if required. */
+ if( pPg->flags&PGHDR_NEED_SYNC
+ || pPager->eState==PAGER_WRITER_CACHEMOD
+ ){
+ rc = syncJournal(pPager, 1);
+ }
+
+ /* Write the contents of the page out to the database file. */
+ if( rc==SQLITE_OK ){
+ assert( (pPg->flags&PGHDR_NEED_SYNC)==0 );
+ rc = pager_write_pagelist(pPager, pPg);
+ }
+ }
+
+ /* Mark the page as clean. */
+ if( rc==SQLITE_OK ){
+ PAGERTRACE(("STRESS %d page %d\n", PAGERID(pPager), pPg->pgno));
+ sqlite3PcacheMakeClean(pPg);
+ }
+
+ return pager_error(pPager, rc);
+}
+
+/*
+** Flush all unreferenced dirty pages to disk.
+*/
+SQLITE_PRIVATE int sqlite3PagerFlush(Pager *pPager){
+ int rc = pPager->errCode;
+ if( !MEMDB ){
+ PgHdr *pList = sqlite3PcacheDirtyList(pPager->pPCache);
+ assert( assert_pager_state(pPager) );
+ while( rc==SQLITE_OK && pList ){
+ PgHdr *pNext = pList->pDirty;
+ if( pList->nRef==0 ){
+ rc = pagerStress((void*)pPager, pList);
+ }
+ pList = pNext;
+ }
+ }
+
+ return rc;
+}
+
+/*
+** Allocate and initialize a new Pager object and put a pointer to it
+** in *ppPager. The pager should eventually be freed by passing it
+** to sqlite3PagerClose().
+**
+** The zFilename argument is the path to the database file to open.
+** If zFilename is NULL then a randomly-named temporary file is created
+** and used as the file to be cached. Temporary files are be deleted
+** automatically when they are closed. If zFilename is ":memory:" then
+** all information is held in cache. It is never written to disk.
+** This can be used to implement an in-memory database.
+**
+** The nExtra parameter specifies the number of bytes of space allocated
+** along with each page reference. This space is available to the user
+** via the sqlite3PagerGetExtra() API. When a new page is allocated, the
+** first 8 bytes of this space are zeroed but the remainder is uninitialized.
+** (The extra space is used by btree as the MemPage object.)
+**
+** The flags argument is used to specify properties that affect the
+** operation of the pager. It should be passed some bitwise combination
+** of the PAGER_* flags.
+**
+** The vfsFlags parameter is a bitmask to pass to the flags parameter
+** of the xOpen() method of the supplied VFS when opening files.
+**
+** If the pager object is allocated and the specified file opened
+** successfully, SQLITE_OK is returned and *ppPager set to point to
+** the new pager object. If an error occurs, *ppPager is set to NULL
+** and error code returned. This function may return SQLITE_NOMEM
+** (sqlite3Malloc() is used to allocate memory), SQLITE_CANTOPEN or
+** various SQLITE_IO_XXX errors.
+*/
+SQLITE_PRIVATE int sqlite3PagerOpen(
+ sqlite3_vfs *pVfs, /* The virtual file system to use */
+ Pager **ppPager, /* OUT: Return the Pager structure here */
+ const char *zFilename, /* Name of the database file to open */
+ int nExtra, /* Extra bytes append to each in-memory page */
+ int flags, /* flags controlling this file */
+ int vfsFlags, /* flags passed through to sqlite3_vfs.xOpen() */
+ void (*xReinit)(DbPage*) /* Function to reinitialize pages */
+){
+ u8 *pPtr;
+ Pager *pPager = 0; /* Pager object to allocate and return */
+ int rc = SQLITE_OK; /* Return code */
+ int tempFile = 0; /* True for temp files (incl. in-memory files) */
+ int memDb = 0; /* True if this is an in-memory file */
+#ifdef SQLITE_ENABLE_DESERIALIZE
+ int memJM = 0; /* Memory journal mode */
+#else
+# define memJM 0
+#endif
+ int readOnly = 0; /* True if this is a read-only file */
+ int journalFileSize; /* Bytes to allocate for each journal fd */
+ char *zPathname = 0; /* Full path to database file */
+ int nPathname = 0; /* Number of bytes in zPathname */
+ int useJournal = (flags & PAGER_OMIT_JOURNAL)==0; /* False to omit journal */
+ int pcacheSize = sqlite3PcacheSize(); /* Bytes to allocate for PCache */
+ u32 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE; /* Default page size */
+ const char *zUri = 0; /* URI args to copy */
+ int nUri = 0; /* Number of bytes of URI args at *zUri */
+
+ /* Figure out how much space is required for each journal file-handle
+ ** (there are two of them, the main journal and the sub-journal). */
+ journalFileSize = ROUND8(sqlite3JournalSize(pVfs));
+
+ /* Set the output variable to NULL in case an error occurs. */
+ *ppPager = 0;
+
+#ifndef SQLITE_OMIT_MEMORYDB
+ if( flags & PAGER_MEMORY ){
+ memDb = 1;
+ if( zFilename && zFilename[0] ){
+ zPathname = sqlite3DbStrDup(0, zFilename);
+ if( zPathname==0 ) return SQLITE_NOMEM_BKPT;
+ nPathname = sqlite3Strlen30(zPathname);
+ zFilename = 0;
+ }
+ }
+#endif
+
+ /* Compute and store the full pathname in an allocated buffer pointed
+ ** to by zPathname, length nPathname. Or, if this is a temporary file,
+ ** leave both nPathname and zPathname set to 0.
+ */
+ if( zFilename && zFilename[0] ){
+ const char *z;
+ nPathname = pVfs->mxPathname+1;
+ zPathname = sqlite3DbMallocRaw(0, nPathname*2);
+ if( zPathname==0 ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
+ rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);
+ nPathname = sqlite3Strlen30(zPathname);
+ z = zUri = &zFilename[sqlite3Strlen30(zFilename)+1];
+ while( *z ){
+ z += sqlite3Strlen30(z)+1;
+ z += sqlite3Strlen30(z)+1;
+ }
+ nUri = (int)(&z[1] - zUri);
+ assert( nUri>=0 );
+ if( rc==SQLITE_OK && nPathname+8>pVfs->mxPathname ){
+ /* This branch is taken when the journal path required by
+ ** the database being opened will be more than pVfs->mxPathname
+ ** bytes in length. This means the database cannot be opened,
+ ** as it will not be possible to open the journal file or even
+ ** check for a hot-journal before reading.
+ */
+ rc = SQLITE_CANTOPEN_BKPT;
+ }
+ if( rc!=SQLITE_OK ){
+ sqlite3DbFree(0, zPathname);
+ return rc;
+ }
+ }
+
+ /* Allocate memory for the Pager structure, PCache object, the
+ ** three file descriptors, the database file name and the journal
+ ** file name. The layout in memory is as follows:
+ **
+ ** Pager object (sizeof(Pager) bytes)
+ ** PCache object (sqlite3PcacheSize() bytes)
+ ** Database file handle (pVfs->szOsFile bytes)
+ ** Sub-journal file handle (journalFileSize bytes)
+ ** Main journal file handle (journalFileSize bytes)
+ ** Database file name (nPathname+1 bytes)
+ ** Journal file name (nPathname+8+1 bytes)
+ */
+ pPtr = (u8 *)sqlite3MallocZero(
+ ROUND8(sizeof(*pPager)) + /* Pager structure */
+ ROUND8(pcacheSize) + /* PCache object */
+ ROUND8(pVfs->szOsFile) + /* The main db file */
+ journalFileSize * 2 + /* The two journal files */
+ nPathname + 1 + nUri + /* zFilename */
+ nPathname + 8 + 2 /* zJournal */
+#ifndef SQLITE_OMIT_WAL
+ + nPathname + 4 + 2 /* zWal */
+#endif
+ );
+ assert( EIGHT_BYTE_ALIGNMENT(SQLITE_INT_TO_PTR(journalFileSize)) );
+ if( !pPtr ){
+ sqlite3DbFree(0, zPathname);
+ return SQLITE_NOMEM_BKPT;
+ }
+ pPager = (Pager*)(pPtr);
+ pPager->pPCache = (PCache*)(pPtr += ROUND8(sizeof(*pPager)));
+ pPager->fd = (sqlite3_file*)(pPtr += ROUND8(pcacheSize));
+ pPager->sjfd = (sqlite3_file*)(pPtr += ROUND8(pVfs->szOsFile));
+ pPager->jfd = (sqlite3_file*)(pPtr += journalFileSize);
+ pPager->zFilename = (char*)(pPtr += journalFileSize);
+ assert( EIGHT_BYTE_ALIGNMENT(pPager->jfd) );
+
+ /* Fill in the Pager.zFilename and Pager.zJournal buffers, if required. */
+ if( zPathname ){
+ assert( nPathname>0 );
+ pPager->zJournal = (char*)(pPtr += nPathname + 1 + nUri);
+ memcpy(pPager->zFilename, zPathname, nPathname);
+ if( nUri ) memcpy(&pPager->zFilename[nPathname+1], zUri, nUri);
+ memcpy(pPager->zJournal, zPathname, nPathname);
+ memcpy(&pPager->zJournal[nPathname], "-journal\000", 8+2);
+ sqlite3FileSuffix3(pPager->zFilename, pPager->zJournal);
+#ifndef SQLITE_OMIT_WAL
+ pPager->zWal = &pPager->zJournal[nPathname+8+1];
+ memcpy(pPager->zWal, zPathname, nPathname);
+ memcpy(&pPager->zWal[nPathname], "-wal\000", 4+1);
+ sqlite3FileSuffix3(pPager->zFilename, pPager->zWal);
+#endif
+ sqlite3DbFree(0, zPathname);
+ }
+ pPager->pVfs = pVfs;
+ pPager->vfsFlags = vfsFlags;
+
+ /* Open the pager file.
+ */
+ if( zFilename && zFilename[0] ){
+ int fout = 0; /* VFS flags returned by xOpen() */
+ rc = sqlite3OsOpen(pVfs, pPager->zFilename, pPager->fd, vfsFlags, &fout);
+ assert( !memDb );
+#ifdef SQLITE_ENABLE_DESERIALIZE
+ memJM = (fout&SQLITE_OPEN_MEMORY)!=0;
+#endif
+ readOnly = (fout&SQLITE_OPEN_READONLY)!=0;
+
+ /* If the file was successfully opened for read/write access,
+ ** choose a default page size in case we have to create the
+ ** database file. The default page size is the maximum of:
+ **
+ ** + SQLITE_DEFAULT_PAGE_SIZE,
+ ** + The value returned by sqlite3OsSectorSize()
+ ** + The largest page size that can be written atomically.
+ */
+ if( rc==SQLITE_OK ){
+ int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
+ if( !readOnly ){
+ setSectorSize(pPager);
+ assert(SQLITE_DEFAULT_PAGE_SIZE<=SQLITE_MAX_DEFAULT_PAGE_SIZE);
+ if( szPageDfltsectorSize ){
+ if( pPager->sectorSize>SQLITE_MAX_DEFAULT_PAGE_SIZE ){
+ szPageDflt = SQLITE_MAX_DEFAULT_PAGE_SIZE;
+ }else{
+ szPageDflt = (u32)pPager->sectorSize;
+ }
+ }
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+ {
+ int ii;
+ assert(SQLITE_IOCAP_ATOMIC512==(512>>8));
+ assert(SQLITE_IOCAP_ATOMIC64K==(65536>>8));
+ assert(SQLITE_MAX_DEFAULT_PAGE_SIZE<=65536);
+ for(ii=szPageDflt; ii<=SQLITE_MAX_DEFAULT_PAGE_SIZE; ii=ii*2){
+ if( iDc&(SQLITE_IOCAP_ATOMIC|(ii>>8)) ){
+ szPageDflt = ii;
+ }
+ }
+ }
+#endif
+ }
+ pPager->noLock = sqlite3_uri_boolean(zFilename, "nolock", 0);
+ if( (iDc & SQLITE_IOCAP_IMMUTABLE)!=0
+ || sqlite3_uri_boolean(zFilename, "immutable", 0) ){
+ vfsFlags |= SQLITE_OPEN_READONLY;
+ goto act_like_temp_file;
+ }
+ }
+ }else{
+ /* If a temporary file is requested, it is not opened immediately.
+ ** In this case we accept the default page size and delay actually
+ ** opening the file until the first call to OsWrite().
+ **
+ ** This branch is also run for an in-memory database. An in-memory
+ ** database is the same as a temp-file that is never written out to
+ ** disk and uses an in-memory rollback journal.
+ **
+ ** This branch also runs for files marked as immutable.
+ */
+act_like_temp_file:
+ tempFile = 1;
+ pPager->eState = PAGER_READER; /* Pretend we already have a lock */
+ pPager->eLock = EXCLUSIVE_LOCK; /* Pretend we are in EXCLUSIVE mode */
+ pPager->noLock = 1; /* Do no locking */
+ readOnly = (vfsFlags&SQLITE_OPEN_READONLY);
+ }
+
+ /* The following call to PagerSetPagesize() serves to set the value of
+ ** Pager.pageSize and to allocate the Pager.pTmpSpace buffer.
+ */
+ if( rc==SQLITE_OK ){
+ assert( pPager->memDb==0 );
+ rc = sqlite3PagerSetPagesize(pPager, &szPageDflt, -1);
+ testcase( rc!=SQLITE_OK );
+ }
+
+ /* Initialize the PCache object. */
+ if( rc==SQLITE_OK ){
+ nExtra = ROUND8(nExtra);
+ assert( nExtra>=8 && nExtra<1000 );
+ rc = sqlite3PcacheOpen(szPageDflt, nExtra, !memDb,
+ !memDb?pagerStress:0, (void *)pPager, pPager->pPCache);
+ }
+
+ /* If an error occurred above, free the Pager structure and close the file.
+ */
+ if( rc!=SQLITE_OK ){
+ sqlite3OsClose(pPager->fd);
+ sqlite3PageFree(pPager->pTmpSpace);
+ sqlite3_free(pPager);
+ return rc;
+ }
+
+ PAGERTRACE(("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename));
+ IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename))
+
+ pPager->useJournal = (u8)useJournal;
+ /* pPager->stmtOpen = 0; */
+ /* pPager->stmtInUse = 0; */
+ /* pPager->nRef = 0; */
+ /* pPager->stmtSize = 0; */
+ /* pPager->stmtJSize = 0; */
+ /* pPager->nPage = 0; */
+ pPager->mxPgno = SQLITE_MAX_PAGE_COUNT;
+ /* pPager->state = PAGER_UNLOCK; */
+ /* pPager->errMask = 0; */
+ pPager->tempFile = (u8)tempFile;
+ assert( tempFile==PAGER_LOCKINGMODE_NORMAL
+ || tempFile==PAGER_LOCKINGMODE_EXCLUSIVE );
+ assert( PAGER_LOCKINGMODE_EXCLUSIVE==1 );
+ pPager->exclusiveMode = (u8)tempFile;
+ pPager->changeCountDone = pPager->tempFile;
+ pPager->memDb = (u8)memDb;
+ pPager->readOnly = (u8)readOnly;
+ assert( useJournal || pPager->tempFile );
+ pPager->noSync = pPager->tempFile;
+ if( pPager->noSync ){
+ assert( pPager->fullSync==0 );
+ assert( pPager->extraSync==0 );
+ assert( pPager->syncFlags==0 );
+ assert( pPager->walSyncFlags==0 );
+ }else{
+ pPager->fullSync = 1;
+ pPager->extraSync = 0;
+ pPager->syncFlags = SQLITE_SYNC_NORMAL;
+ pPager->walSyncFlags = SQLITE_SYNC_NORMAL | (SQLITE_SYNC_NORMAL<<2);
+ }
+ /* pPager->pFirst = 0; */
+ /* pPager->pFirstSynced = 0; */
+ /* pPager->pLast = 0; */
+ pPager->nExtra = (u16)nExtra;
+ pPager->journalSizeLimit = SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT;
+ assert( isOpen(pPager->fd) || tempFile );
+ setSectorSize(pPager);
+ if( !useJournal ){
+ pPager->journalMode = PAGER_JOURNALMODE_OFF;
+ }else if( memDb || memJM ){
+ pPager->journalMode = PAGER_JOURNALMODE_MEMORY;
+ }
+ /* pPager->xBusyHandler = 0; */
+ /* pPager->pBusyHandlerArg = 0; */
+ pPager->xReiniter = xReinit;
+ setGetterMethod(pPager);
+ /* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */
+ /* pPager->szMmap = SQLITE_DEFAULT_MMAP_SIZE // will be set by btree.c */
+
+ *ppPager = pPager;
+ return SQLITE_OK;
+}
+
+
+
+/*
+** This function is called after transitioning from PAGER_UNLOCK to
+** PAGER_SHARED state. It tests if there is a hot journal present in
+** the file-system for the given pager. A hot journal is one that
+** needs to be played back. According to this function, a hot-journal
+** file exists if the following criteria are met:
+**
+** * The journal file exists in the file system, and
+** * No process holds a RESERVED or greater lock on the database file, and
+** * The database file itself is greater than 0 bytes in size, and
+** * The first byte of the journal file exists and is not 0x00.
+**
+** If the current size of the database file is 0 but a journal file
+** exists, that is probably an old journal left over from a prior
+** database with the same name. In this case the journal file is
+** just deleted using OsDelete, *pExists is set to 0 and SQLITE_OK
+** is returned.
+**
+** This routine does not check if there is a master journal filename
+** at the end of the file. If there is, and that master journal file
+** does not exist, then the journal file is not really hot. In this
+** case this routine will return a false-positive. The pager_playback()
+** routine will discover that the journal file is not really hot and
+** will not roll it back.
+**
+** If a hot-journal file is found to exist, *pExists is set to 1 and
+** SQLITE_OK returned. If no hot-journal file is present, *pExists is
+** set to 0 and SQLITE_OK returned. If an IO error occurs while trying
+** to determine whether or not a hot-journal file exists, the IO error
+** code is returned and the value of *pExists is undefined.
+*/
+static int hasHotJournal(Pager *pPager, int *pExists){
+ sqlite3_vfs * const pVfs = pPager->pVfs;
+ int rc = SQLITE_OK; /* Return code */
+ int exists = 1; /* True if a journal file is present */
+ int jrnlOpen = !!isOpen(pPager->jfd);
+
+ assert( pPager->useJournal );
+ assert( isOpen(pPager->fd) );
+ assert( pPager->eState==PAGER_OPEN );
+
+ assert( jrnlOpen==0 || ( sqlite3OsDeviceCharacteristics(pPager->jfd) &
+ SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
+ ));
+
+ *pExists = 0;
+ if( !jrnlOpen ){
+ rc = sqlite3OsAccess(pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &exists);
+ }
+ if( rc==SQLITE_OK && exists ){
+ int locked = 0; /* True if some process holds a RESERVED lock */
+
+ /* Race condition here: Another process might have been holding the
+ ** the RESERVED lock and have a journal open at the sqlite3OsAccess()
+ ** call above, but then delete the journal and drop the lock before
+ ** we get to the following sqlite3OsCheckReservedLock() call. If that
+ ** is the case, this routine might think there is a hot journal when
+ ** in fact there is none. This results in a false-positive which will
+ ** be dealt with by the playback routine. Ticket #3883.
+ */
+ rc = sqlite3OsCheckReservedLock(pPager->fd, &locked);
+ if( rc==SQLITE_OK && !locked ){
+ Pgno nPage; /* Number of pages in database file */
+
+ assert( pPager->tempFile==0 );
+ rc = pagerPagecount(pPager, &nPage);
+ if( rc==SQLITE_OK ){
+ /* If the database is zero pages in size, that means that either (1) the
+ ** journal is a remnant from a prior database with the same name where
+ ** the database file but not the journal was deleted, or (2) the initial
+ ** transaction that populates a new database is being rolled back.
+ ** In either case, the journal file can be deleted. However, take care
+ ** not to delete the journal file if it is already open due to
+ ** journal_mode=PERSIST.
+ */
+ if( nPage==0 && !jrnlOpen ){
+ sqlite3BeginBenignMalloc();
+ if( pagerLockDb(pPager, RESERVED_LOCK)==SQLITE_OK ){
+ sqlite3OsDelete(pVfs, pPager->zJournal, 0);
+ if( !pPager->exclusiveMode ) pagerUnlockDb(pPager, SHARED_LOCK);
+ }
+ sqlite3EndBenignMalloc();
+ }else{
+ /* The journal file exists and no other connection has a reserved
+ ** or greater lock on the database file. Now check that there is
+ ** at least one non-zero bytes at the start of the journal file.
+ ** If there is, then we consider this journal to be hot. If not,
+ ** it can be ignored.
+ */
+ if( !jrnlOpen ){
+ int f = SQLITE_OPEN_READONLY|SQLITE_OPEN_MAIN_JOURNAL;
+ rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &f);
+ }
+ if( rc==SQLITE_OK ){
+ u8 first = 0;
+ rc = sqlite3OsRead(pPager->jfd, (void *)&first, 1, 0);
+ if( rc==SQLITE_IOERR_SHORT_READ ){
+ rc = SQLITE_OK;
+ }
+ if( !jrnlOpen ){
+ sqlite3OsClose(pPager->jfd);
+ }
+ *pExists = (first!=0);
+ }else if( rc==SQLITE_CANTOPEN ){
+ /* If we cannot open the rollback journal file in order to see if
+ ** it has a zero header, that might be due to an I/O error, or
+ ** it might be due to the race condition described above and in
+ ** ticket #3883. Either way, assume that the journal is hot.
+ ** This might be a false positive. But if it is, then the
+ ** automatic journal playback and recovery mechanism will deal
+ ** with it under an EXCLUSIVE lock where we do not need to
+ ** worry so much with race conditions.
+ */
+ *pExists = 1;
+ rc = SQLITE_OK;
+ }
+ }
+ }
+ }
+ }
+
+ return rc;
+}
+
+/*
+** This function is called to obtain a shared lock on the database file.
+** It is illegal to call sqlite3PagerGet() until after this function
+** has been successfully called. If a shared-lock is already held when
+** this function is called, it is a no-op.
+**
+** The following operations are also performed by this function.
+**
+** 1) If the pager is currently in PAGER_OPEN state (no lock held
+** on the database file), then an attempt is made to obtain a
+** SHARED lock on the database file. Immediately after obtaining
+** the SHARED lock, the file-system is checked for a hot-journal,
+** which is played back if present. Following any hot-journal
+** rollback, the contents of the cache are validated by checking
+** the 'change-counter' field of the database file header and
+** discarded if they are found to be invalid.
+**
+** 2) If the pager is running in exclusive-mode, and there are currently
+** no outstanding references to any pages, and is in the error state,
+** then an attempt is made to clear the error state by discarding
+** the contents of the page cache and rolling back any open journal
+** file.
+**
+** If everything is successful, SQLITE_OK is returned. If an IO error
+** occurs while locking the database, checking for a hot-journal file or
+** rolling back a journal file, the IO error code is returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+
+ /* This routine is only called from b-tree and only when there are no
+ ** outstanding pages. This implies that the pager state should either
+ ** be OPEN or READER. READER is only possible if the pager is or was in
+ ** exclusive access mode. */
+ assert( sqlite3PcacheRefCount(pPager->pPCache)==0 );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->eState==PAGER_OPEN || pPager->eState==PAGER_READER );
+ assert( pPager->errCode==SQLITE_OK );
+
+ if( !pagerUseWal(pPager) && pPager->eState==PAGER_OPEN ){
+ int bHotJournal = 1; /* True if there exists a hot journal-file */
+
+ assert( !MEMDB );
+ assert( pPager->tempFile==0 || pPager->eLock==EXCLUSIVE_LOCK );
+
+ rc = pager_wait_on_lock(pPager, SHARED_LOCK);
+ if( rc!=SQLITE_OK ){
+ assert( pPager->eLock==NO_LOCK || pPager->eLock==UNKNOWN_LOCK );
+ goto failed;
+ }
+
+ /* If a journal file exists, and there is no RESERVED lock on the
+ ** database file, then it either needs to be played back or deleted.
+ */
+ if( pPager->eLock<=SHARED_LOCK ){
+ rc = hasHotJournal(pPager, &bHotJournal);
+ }
+ if( rc!=SQLITE_OK ){
+ goto failed;
+ }
+ if( bHotJournal ){
+ if( pPager->readOnly ){
+ rc = SQLITE_READONLY_ROLLBACK;
+ goto failed;
+ }
+
+ /* Get an EXCLUSIVE lock on the database file. At this point it is
+ ** important that a RESERVED lock is not obtained on the way to the
+ ** EXCLUSIVE lock. If it were, another process might open the
+ ** database file, detect the RESERVED lock, and conclude that the
+ ** database is safe to read while this process is still rolling the
+ ** hot-journal back.
+ **
+ ** Because the intermediate RESERVED lock is not requested, any
+ ** other process attempting to access the database file will get to
+ ** this point in the code and fail to obtain its own EXCLUSIVE lock
+ ** on the database file.
+ **
+ ** Unless the pager is in locking_mode=exclusive mode, the lock is
+ ** downgraded to SHARED_LOCK before this function returns.
+ */
+ rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
+ if( rc!=SQLITE_OK ){
+ goto failed;
+ }
+
+ /* If it is not already open and the file exists on disk, open the
+ ** journal for read/write access. Write access is required because
+ ** in exclusive-access mode the file descriptor will be kept open
+ ** and possibly used for a transaction later on. Also, write-access
+ ** is usually required to finalize the journal in journal_mode=persist
+ ** mode (and also for journal_mode=truncate on some systems).
+ **
+ ** If the journal does not exist, it usually means that some
+ ** other connection managed to get in and roll it back before
+ ** this connection obtained the exclusive lock above. Or, it
+ ** may mean that the pager was in the error-state when this
+ ** function was called and the journal file does not exist.
+ */
+ if( !isOpen(pPager->jfd) ){
+ sqlite3_vfs * const pVfs = pPager->pVfs;
+ int bExists; /* True if journal file exists */
+ rc = sqlite3OsAccess(
+ pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &bExists);
+ if( rc==SQLITE_OK && bExists ){
+ int fout = 0;
+ int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_JOURNAL;
+ assert( !pPager->tempFile );
+ rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &fout);
+ assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+ if( rc==SQLITE_OK && fout&SQLITE_OPEN_READONLY ){
+ rc = SQLITE_CANTOPEN_BKPT;
+ sqlite3OsClose(pPager->jfd);
+ }
+ }
+ }
+
+ /* Playback and delete the journal. Drop the database write
+ ** lock and reacquire the read lock. Purge the cache before
+ ** playing back the hot-journal so that we don't end up with
+ ** an inconsistent cache. Sync the hot journal before playing
+ ** it back since the process that crashed and left the hot journal
+ ** probably did not sync it and we are required to always sync
+ ** the journal before playing it back.
+ */
+ if( isOpen(pPager->jfd) ){
+ assert( rc==SQLITE_OK );
+ rc = pagerSyncHotJournal(pPager);
+ if( rc==SQLITE_OK ){
+ rc = pager_playback(pPager, !pPager->tempFile);
+ pPager->eState = PAGER_OPEN;
+ }
+ }else if( !pPager->exclusiveMode ){
+ pagerUnlockDb(pPager, SHARED_LOCK);
+ }
+
+ if( rc!=SQLITE_OK ){
+ /* This branch is taken if an error occurs while trying to open
+ ** or roll back a hot-journal while holding an EXCLUSIVE lock. The
+ ** pager_unlock() routine will be called before returning to unlock
+ ** the file. If the unlock attempt fails, then Pager.eLock must be
+ ** set to UNKNOWN_LOCK (see the comment above the #define for
+ ** UNKNOWN_LOCK above for an explanation).
+ **
+ ** In order to get pager_unlock() to do this, set Pager.eState to
+ ** PAGER_ERROR now. This is not actually counted as a transition
+ ** to ERROR state in the state diagram at the top of this file,
+ ** since we know that the same call to pager_unlock() will very
+ ** shortly transition the pager object to the OPEN state. Calling
+ ** assert_pager_state() would fail now, as it should not be possible
+ ** to be in ERROR state when there are zero outstanding page
+ ** references.
+ */
+ pager_error(pPager, rc);
+ goto failed;
+ }
+
+ assert( pPager->eState==PAGER_OPEN );
+ assert( (pPager->eLock==SHARED_LOCK)
+ || (pPager->exclusiveMode && pPager->eLock>SHARED_LOCK)
+ );
+ }
+
+ if( !pPager->tempFile && pPager->hasHeldSharedLock ){
+ /* The shared-lock has just been acquired then check to
+ ** see if the database has been modified. If the database has changed,
+ ** flush the cache. The hasHeldSharedLock flag prevents this from
+ ** occurring on the very first access to a file, in order to save a
+ ** single unnecessary sqlite3OsRead() call at the start-up.
+ **
+ ** Database changes are detected by looking at 15 bytes beginning
+ ** at offset 24 into the file. The first 4 of these 16 bytes are
+ ** a 32-bit counter that is incremented with each change. The
+ ** other bytes change randomly with each file change when
+ ** a codec is in use.
+ **
+ ** There is a vanishingly small chance that a change will not be
+ ** detected. The chance of an undetected change is so small that
+ ** it can be neglected.
+ */
+ char dbFileVers[sizeof(pPager->dbFileVers)];
+
+ IOTRACE(("CKVERS %p %d\n", pPager, sizeof(dbFileVers)));
+ rc = sqlite3OsRead(pPager->fd, &dbFileVers, sizeof(dbFileVers), 24);
+ if( rc!=SQLITE_OK ){
+ if( rc!=SQLITE_IOERR_SHORT_READ ){
+ goto failed;
+ }
+ memset(dbFileVers, 0, sizeof(dbFileVers));
+ }
+
+ if( memcmp(pPager->dbFileVers, dbFileVers, sizeof(dbFileVers))!=0 ){
+ pager_reset(pPager);
+
+ /* Unmap the database file. It is possible that external processes
+ ** may have truncated the database file and then extended it back
+ ** to its original size while this process was not holding a lock.
+ ** In this case there may exist a Pager.pMap mapping that appears
+ ** to be the right size but is not actually valid. Avoid this
+ ** possibility by unmapping the db here. */
+ if( USEFETCH(pPager) ){
+ sqlite3OsUnfetch(pPager->fd, 0, 0);
+ }
+ }
+ }
+
+ /* If there is a WAL file in the file-system, open this database in WAL
+ ** mode. Otherwise, the following function call is a no-op.
+ */
+ rc = pagerOpenWalIfPresent(pPager);
+#ifndef SQLITE_OMIT_WAL
+ assert( pPager->pWal==0 || rc==SQLITE_OK );
+#endif
+ }
+
+ if( pagerUseWal(pPager) ){
+ assert( rc==SQLITE_OK );
+ rc = pagerBeginReadTransaction(pPager);
+ }
+
+ if( pPager->tempFile==0 && pPager->eState==PAGER_OPEN && rc==SQLITE_OK ){
+ rc = pagerPagecount(pPager, &pPager->dbSize);
+ }
+
+ failed:
+ if( rc!=SQLITE_OK ){
+ assert( !MEMDB );
+ pager_unlock(pPager);
+ assert( pPager->eState==PAGER_OPEN );
+ }else{
+ pPager->eState = PAGER_READER;
+ pPager->hasHeldSharedLock = 1;
+ }
+ return rc;
+}
+
+/*
+** If the reference count has reached zero, rollback any active
+** transaction and unlock the pager.
+**
+** Except, in locking_mode=EXCLUSIVE when there is nothing to in
+** the rollback journal, the unlock is not performed and there is
+** nothing to rollback, so this routine is a no-op.
+*/
+static void pagerUnlockIfUnused(Pager *pPager){
+ if( sqlite3PcacheRefCount(pPager->pPCache)==0 ){
+ assert( pPager->nMmapOut==0 ); /* because page1 is never memory mapped */
+ pagerUnlockAndRollback(pPager);
+ }
+}
+
+/*
+** The page getter methods each try to acquire a reference to a
+** page with page number pgno. If the requested reference is
+** successfully obtained, it is copied to *ppPage and SQLITE_OK returned.
+**
+** There are different implementations of the getter method depending
+** on the current state of the pager.
+**
+** getPageNormal() -- The normal getter
+** getPageError() -- Used if the pager is in an error state
+** getPageMmap() -- Used if memory-mapped I/O is enabled
+**
+** If the requested page is already in the cache, it is returned.
+** Otherwise, a new page object is allocated and populated with data
+** read from the database file. In some cases, the pcache module may
+** choose not to allocate a new page object and may reuse an existing
+** object with no outstanding references.
+**
+** The extra data appended to a page is always initialized to zeros the
+** first time a page is loaded into memory. If the page requested is
+** already in the cache when this function is called, then the extra
+** data is left as it was when the page object was last used.
+**
+** If the database image is smaller than the requested page or if
+** the flags parameter contains the PAGER_GET_NOCONTENT bit and the
+** requested page is not already stored in the cache, then no
+** actual disk read occurs. In this case the memory image of the
+** page is initialized to all zeros.
+**
+** If PAGER_GET_NOCONTENT is true, it means that we do not care about
+** the contents of the page. This occurs in two scenarios:
+**
+** a) When reading a free-list leaf page from the database, and
+**
+** b) When a savepoint is being rolled back and we need to load
+** a new page into the cache to be filled with the data read
+** from the savepoint journal.
+**
+** If PAGER_GET_NOCONTENT is true, then the data returned is zeroed instead
+** of being read from the database. Additionally, the bits corresponding
+** to pgno in Pager.pInJournal (bitvec of pages already written to the
+** journal file) and the PagerSavepoint.pInSavepoint bitvecs of any open
+** savepoints are set. This means if the page is made writable at any
+** point in the future, using a call to sqlite3PagerWrite(), its contents
+** will not be journaled. This saves IO.
+**
+** The acquisition might fail for several reasons. In all cases,
+** an appropriate error code is returned and *ppPage is set to NULL.
+**
+** See also sqlite3PagerLookup(). Both this routine and Lookup() attempt
+** to find a page in the in-memory cache first. If the page is not already
+** in memory, this routine goes to disk to read it in whereas Lookup()
+** just returns 0. This routine acquires a read-lock the first time it
+** has to go to disk, and could also playback an old journal if necessary.
+** Since Lookup() never goes to disk, it never has to deal with locks
+** or journal files.
+*/
+static int getPageNormal(
+ Pager *pPager, /* The pager open on the database file */
+ Pgno pgno, /* Page number to fetch */
+ DbPage **ppPage, /* Write a pointer to the page here */
+ int flags /* PAGER_GET_XXX flags */
+){
+ int rc = SQLITE_OK;
+ PgHdr *pPg;
+ u8 noContent; /* True if PAGER_GET_NOCONTENT is set */
+ sqlite3_pcache_page *pBase;
+
+ assert( pPager->errCode==SQLITE_OK );
+ assert( pPager->eState>=PAGER_READER );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->hasHeldSharedLock==1 );
+
+ if( pgno==0 ) return SQLITE_CORRUPT_BKPT;
+ pBase = sqlite3PcacheFetch(pPager->pPCache, pgno, 3);
+ if( pBase==0 ){
+ pPg = 0;
+ rc = sqlite3PcacheFetchStress(pPager->pPCache, pgno, &pBase);
+ if( rc!=SQLITE_OK ) goto pager_acquire_err;
+ if( pBase==0 ){
+ rc = SQLITE_NOMEM_BKPT;
+ goto pager_acquire_err;
+ }
+ }
+ pPg = *ppPage = sqlite3PcacheFetchFinish(pPager->pPCache, pgno, pBase);
+ assert( pPg==(*ppPage) );
+ assert( pPg->pgno==pgno );
+ assert( pPg->pPager==pPager || pPg->pPager==0 );
+
+ noContent = (flags & PAGER_GET_NOCONTENT)!=0;
+ if( pPg->pPager && !noContent ){
+ /* In this case the pcache already contains an initialized copy of
+ ** the page. Return without further ado. */
+ assert( pgno<=PAGER_MAX_PGNO && pgno!=PAGER_MJ_PGNO(pPager) );
+ pPager->aStat[PAGER_STAT_HIT]++;
+ return SQLITE_OK;
+
+ }else{
+ /* The pager cache has created a new page. Its content needs to
+ ** be initialized. But first some error checks:
+ **
+ ** (1) The maximum page number is 2^31
+ ** (2) Never try to fetch the locking page
+ */
+ if( pgno>PAGER_MAX_PGNO || pgno==PAGER_MJ_PGNO(pPager) ){
+ rc = SQLITE_CORRUPT_BKPT;
+ goto pager_acquire_err;
+ }
+
+ pPg->pPager = pPager;
+
+ assert( !isOpen(pPager->fd) || !MEMDB );
+ if( !isOpen(pPager->fd) || pPager->dbSizepPager->mxPgno ){
+ rc = SQLITE_FULL;
+ goto pager_acquire_err;
+ }
+ if( noContent ){
+ /* Failure to set the bits in the InJournal bit-vectors is benign.
+ ** It merely means that we might do some extra work to journal a
+ ** page that does not need to be journaled. Nevertheless, be sure
+ ** to test the case where a malloc error occurs while trying to set
+ ** a bit in a bit vector.
+ */
+ sqlite3BeginBenignMalloc();
+ if( pgno<=pPager->dbOrigSize ){
+ TESTONLY( rc = ) sqlite3BitvecSet(pPager->pInJournal, pgno);
+ testcase( rc==SQLITE_NOMEM );
+ }
+ TESTONLY( rc = ) addToSavepointBitvecs(pPager, pgno);
+ testcase( rc==SQLITE_NOMEM );
+ sqlite3EndBenignMalloc();
+ }
+ memset(pPg->pData, 0, pPager->pageSize);
+ IOTRACE(("ZERO %p %d\n", pPager, pgno));
+ }else{
+ assert( pPg->pPager==pPager );
+ pPager->aStat[PAGER_STAT_MISS]++;
+ rc = readDbPage(pPg);
+ if( rc!=SQLITE_OK ){
+ goto pager_acquire_err;
+ }
+ }
+ pager_set_pagehash(pPg);
+ }
+ return SQLITE_OK;
+
+pager_acquire_err:
+ assert( rc!=SQLITE_OK );
+ if( pPg ){
+ sqlite3PcacheDrop(pPg);
+ }
+ pagerUnlockIfUnused(pPager);
+ *ppPage = 0;
+ return rc;
+}
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/* The page getter for when memory-mapped I/O is enabled */
+static int getPageMMap(
+ Pager *pPager, /* The pager open on the database file */
+ Pgno pgno, /* Page number to fetch */
+ DbPage **ppPage, /* Write a pointer to the page here */
+ int flags /* PAGER_GET_XXX flags */
+){
+ int rc = SQLITE_OK;
+ PgHdr *pPg = 0;
+ u32 iFrame = 0; /* Frame to read from WAL file */
+
+ /* It is acceptable to use a read-only (mmap) page for any page except
+ ** page 1 if there is no write-transaction open or the ACQUIRE_READONLY
+ ** flag was specified by the caller. And so long as the db is not a
+ ** temporary or in-memory database. */
+ const int bMmapOk = (pgno>1
+ && (pPager->eState==PAGER_READER || (flags & PAGER_GET_READONLY))
+ );
+
+ assert( USEFETCH(pPager) );
+#ifdef SQLITE_HAS_CODEC
+ assert( pPager->xCodec==0 );
+#endif
+
+ /* Optimization note: Adding the "pgno<=1" term before "pgno==0" here
+ ** allows the compiler optimizer to reuse the results of the "pgno>1"
+ ** test in the previous statement, and avoid testing pgno==0 in the
+ ** common case where pgno is large. */
+ if( pgno<=1 && pgno==0 ){
+ return SQLITE_CORRUPT_BKPT;
+ }
+ assert( pPager->eState>=PAGER_READER );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->hasHeldSharedLock==1 );
+ assert( pPager->errCode==SQLITE_OK );
+
+ if( bMmapOk && pagerUseWal(pPager) ){
+ rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
+ if( rc!=SQLITE_OK ){
+ *ppPage = 0;
+ return rc;
+ }
+ }
+ if( bMmapOk && iFrame==0 ){
+ void *pData = 0;
+ rc = sqlite3OsFetch(pPager->fd,
+ (i64)(pgno-1) * pPager->pageSize, pPager->pageSize, &pData
+ );
+ if( rc==SQLITE_OK && pData ){
+ if( pPager->eState>PAGER_READER || pPager->tempFile ){
+ pPg = sqlite3PagerLookup(pPager, pgno);
+ }
+ if( pPg==0 ){
+ rc = pagerAcquireMapPage(pPager, pgno, pData, &pPg);
+ }else{
+ sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1)*pPager->pageSize, pData);
+ }
+ if( pPg ){
+ assert( rc==SQLITE_OK );
+ *ppPage = pPg;
+ return SQLITE_OK;
+ }
+ }
+ if( rc!=SQLITE_OK ){
+ *ppPage = 0;
+ return rc;
+ }
+ }
+ return getPageNormal(pPager, pgno, ppPage, flags);
+}
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
+
+/* The page getter method for when the pager is an error state */
+static int getPageError(
+ Pager *pPager, /* The pager open on the database file */
+ Pgno pgno, /* Page number to fetch */
+ DbPage **ppPage, /* Write a pointer to the page here */
+ int flags /* PAGER_GET_XXX flags */
+){
+ UNUSED_PARAMETER(pgno);
+ UNUSED_PARAMETER(flags);
+ assert( pPager->errCode!=SQLITE_OK );
+ *ppPage = 0;
+ return pPager->errCode;
+}
+
+
+/* Dispatch all page fetch requests to the appropriate getter method.
+*/
+SQLITE_PRIVATE int sqlite3PagerGet(
+ Pager *pPager, /* The pager open on the database file */
+ Pgno pgno, /* Page number to fetch */
+ DbPage **ppPage, /* Write a pointer to the page here */
+ int flags /* PAGER_GET_XXX flags */
+){
+ return pPager->xGet(pPager, pgno, ppPage, flags);
+}
+
+/*
+** Acquire a page if it is already in the in-memory cache. Do
+** not read the page from disk. Return a pointer to the page,
+** or 0 if the page is not in cache.
+**
+** See also sqlite3PagerGet(). The difference between this routine
+** and sqlite3PagerGet() is that _get() will go to the disk and read
+** in the page if the page is not already in cache. This routine
+** returns NULL if the page is not in cache or if a disk I/O error
+** has ever happened.
+*/
+SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno){
+ sqlite3_pcache_page *pPage;
+ assert( pPager!=0 );
+ assert( pgno!=0 );
+ assert( pPager->pPCache!=0 );
+ pPage = sqlite3PcacheFetch(pPager->pPCache, pgno, 0);
+ assert( pPage==0 || pPager->hasHeldSharedLock );
+ if( pPage==0 ) return 0;
+ return sqlite3PcacheFetchFinish(pPager->pPCache, pgno, pPage);
+}
+
+/*
+** Release a page reference.
+**
+** The sqlite3PagerUnref() and sqlite3PagerUnrefNotNull() may only be
+** used if we know that the page being released is not the last page.
+** The btree layer always holds page1 open until the end, so these first
+** to routines can be used to release any page other than BtShared.pPage1.
+**
+** Use sqlite3PagerUnrefPageOne() to release page1. This latter routine
+** checks the total number of outstanding pages and if the number of
+** pages reaches zero it drops the database lock.
+*/
+SQLITE_PRIVATE void sqlite3PagerUnrefNotNull(DbPage *pPg){
+ TESTONLY( Pager *pPager = pPg->pPager; )
+ assert( pPg!=0 );
+ if( pPg->flags & PGHDR_MMAP ){
+ assert( pPg->pgno!=1 ); /* Page1 is never memory mapped */
+ pagerReleaseMapPage(pPg);
+ }else{
+ sqlite3PcacheRelease(pPg);
+ }
+ /* Do not use this routine to release the last reference to page1 */
+ assert( sqlite3PcacheRefCount(pPager->pPCache)>0 );
+}
+SQLITE_PRIVATE void sqlite3PagerUnref(DbPage *pPg){
+ if( pPg ) sqlite3PagerUnrefNotNull(pPg);
+}
+SQLITE_PRIVATE void sqlite3PagerUnrefPageOne(DbPage *pPg){
+ Pager *pPager;
+ assert( pPg!=0 );
+ assert( pPg->pgno==1 );
+ assert( (pPg->flags & PGHDR_MMAP)==0 ); /* Page1 is never memory mapped */
+ pPager = pPg->pPager;
+ sqlite3PagerResetLockTimeout(pPager);
+ sqlite3PcacheRelease(pPg);
+ pagerUnlockIfUnused(pPager);
+}
+
+/*
+** This function is called at the start of every write transaction.
+** There must already be a RESERVED or EXCLUSIVE lock on the database
+** file when this routine is called.
+**
+** Open the journal file for pager pPager and write a journal header
+** to the start of it. If there are active savepoints, open the sub-journal
+** as well. This function is only used when the journal file is being
+** opened to write a rollback log for a transaction. It is not used
+** when opening a hot journal file to roll it back.
+**
+** If the journal file is already open (as it may be in exclusive mode),
+** then this function just writes a journal header to the start of the
+** already open file.
+**
+** Whether or not the journal file is opened by this function, the
+** Pager.pInJournal bitvec structure is allocated.
+**
+** Return SQLITE_OK if everything is successful. Otherwise, return
+** SQLITE_NOMEM if the attempt to allocate Pager.pInJournal fails, or
+** an IO error code if opening or writing the journal file fails.
+*/
+static int pager_open_journal(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+ sqlite3_vfs * const pVfs = pPager->pVfs; /* Local cache of vfs pointer */
+
+ assert( pPager->eState==PAGER_WRITER_LOCKED );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->pInJournal==0 );
+
+ /* If already in the error state, this function is a no-op. But on
+ ** the other hand, this routine is never called if we are already in
+ ** an error state. */
+ if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+ if( !pagerUseWal(pPager) && pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
+ pPager->pInJournal = sqlite3BitvecCreate(pPager->dbSize);
+ if( pPager->pInJournal==0 ){
+ return SQLITE_NOMEM_BKPT;
+ }
+
+ /* Open the journal file if it is not already open. */
+ if( !isOpen(pPager->jfd) ){
+ if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ){
+ sqlite3MemJournalOpen(pPager->jfd);
+ }else{
+ int flags = SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE;
+ int nSpill;
+
+ if( pPager->tempFile ){
+ flags |= (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL);
+ nSpill = sqlite3Config.nStmtSpill;
+ }else{
+ flags |= SQLITE_OPEN_MAIN_JOURNAL;
+ nSpill = jrnlBufferSize(pPager);
+ }
+
+ /* Verify that the database still has the same name as it did when
+ ** it was originally opened. */
+ rc = databaseIsUnmoved(pPager);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3JournalOpen (
+ pVfs, pPager->zJournal, pPager->jfd, flags, nSpill
+ );
+ }
+ }
+ assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+ }
+
+
+ /* Write the first journal header to the journal file and open
+ ** the sub-journal if necessary.
+ */
+ if( rc==SQLITE_OK ){
+ /* TODO: Check if all of these are really required. */
+ pPager->nRec = 0;
+ pPager->journalOff = 0;
+ pPager->setMaster = 0;
+ pPager->journalHdr = 0;
+ rc = writeJournalHdr(pPager);
+ }
+ }
+
+ if( rc!=SQLITE_OK ){
+ sqlite3BitvecDestroy(pPager->pInJournal);
+ pPager->pInJournal = 0;
+ }else{
+ assert( pPager->eState==PAGER_WRITER_LOCKED );
+ pPager->eState = PAGER_WRITER_CACHEMOD;
+ }
+
+ return rc;
+}
+
+/*
+** Begin a write-transaction on the specified pager object. If a
+** write-transaction has already been opened, this function is a no-op.
+**
+** If the exFlag argument is false, then acquire at least a RESERVED
+** lock on the database file. If exFlag is true, then acquire at least
+** an EXCLUSIVE lock. If such a lock is already held, no locking
+** functions need be called.
+**
+** If the subjInMemory argument is non-zero, then any sub-journal opened
+** within this transaction will be opened as an in-memory file. This
+** has no effect if the sub-journal is already opened (as it may be when
+** running in exclusive mode) or if the transaction does not require a
+** sub-journal. If the subjInMemory argument is zero, then any required
+** sub-journal is implemented in-memory if pPager is an in-memory database,
+** or using a temporary file otherwise.
+*/
+SQLITE_PRIVATE int sqlite3PagerBegin(Pager *pPager, int exFlag, int subjInMemory){
+ int rc = SQLITE_OK;
+
+ if( pPager->errCode ) return pPager->errCode;
+ assert( pPager->eState>=PAGER_READER && pPager->eStatesubjInMemory = (u8)subjInMemory;
+
+ if( ALWAYS(pPager->eState==PAGER_READER) ){
+ assert( pPager->pInJournal==0 );
+
+ if( pagerUseWal(pPager) ){
+ /* If the pager is configured to use locking_mode=exclusive, and an
+ ** exclusive lock on the database is not already held, obtain it now.
+ */
+ if( pPager->exclusiveMode && sqlite3WalExclusiveMode(pPager->pWal, -1) ){
+ rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ (void)sqlite3WalExclusiveMode(pPager->pWal, 1);
+ }
+
+ /* Grab the write lock on the log file. If successful, upgrade to
+ ** PAGER_RESERVED state. Otherwise, return an error code to the caller.
+ ** The busy-handler is not invoked if another connection already
+ ** holds the write-lock. If possible, the upper layer will call it.
+ */
+ rc = sqlite3WalBeginWriteTransaction(pPager->pWal);
+ }else{
+ /* Obtain a RESERVED lock on the database file. If the exFlag parameter
+ ** is true, then immediately upgrade this to an EXCLUSIVE lock. The
+ ** busy-handler callback can be used when upgrading to the EXCLUSIVE
+ ** lock, but not when obtaining the RESERVED lock.
+ */
+ rc = pagerLockDb(pPager, RESERVED_LOCK);
+ if( rc==SQLITE_OK && exFlag ){
+ rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+ }
+ }
+
+ if( rc==SQLITE_OK ){
+ /* Change to WRITER_LOCKED state.
+ **
+ ** WAL mode sets Pager.eState to PAGER_WRITER_LOCKED or CACHEMOD
+ ** when it has an open transaction, but never to DBMOD or FINISHED.
+ ** This is because in those states the code to roll back savepoint
+ ** transactions may copy data from the sub-journal into the database
+ ** file as well as into the page cache. Which would be incorrect in
+ ** WAL mode.
+ */
+ pPager->eState = PAGER_WRITER_LOCKED;
+ pPager->dbHintSize = pPager->dbSize;
+ pPager->dbFileSize = pPager->dbSize;
+ pPager->dbOrigSize = pPager->dbSize;
+ pPager->journalOff = 0;
+ }
+
+ assert( rc==SQLITE_OK || pPager->eState==PAGER_READER );
+ assert( rc!=SQLITE_OK || pPager->eState==PAGER_WRITER_LOCKED );
+ assert( assert_pager_state(pPager) );
+ }
+
+ PAGERTRACE(("TRANSACTION %d\n", PAGERID(pPager)));
+ return rc;
+}
+
+/*
+** Write page pPg onto the end of the rollback journal.
+*/
+static SQLITE_NOINLINE int pagerAddPageToRollbackJournal(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ int rc;
+ u32 cksum;
+ char *pData2;
+ i64 iOff = pPager->journalOff;
+
+ /* We should never write to the journal file the page that
+ ** contains the database locks. The following assert verifies
+ ** that we do not. */
+ assert( pPg->pgno!=PAGER_MJ_PGNO(pPager) );
+
+ assert( pPager->journalHdr<=pPager->journalOff );
+ CODEC2(pPager, pPg->pData, pPg->pgno, 7, return SQLITE_NOMEM_BKPT, pData2);
+ cksum = pager_cksum(pPager, (u8*)pData2);
+
+ /* Even if an IO or diskfull error occurs while journalling the
+ ** page in the block above, set the need-sync flag for the page.
+ ** Otherwise, when the transaction is rolled back, the logic in
+ ** playback_one_page() will think that the page needs to be restored
+ ** in the database file. And if an IO error occurs while doing so,
+ ** then corruption may follow.
+ */
+ pPg->flags |= PGHDR_NEED_SYNC;
+
+ rc = write32bits(pPager->jfd, iOff, pPg->pgno);
+ if( rc!=SQLITE_OK ) return rc;
+ rc = sqlite3OsWrite(pPager->jfd, pData2, pPager->pageSize, iOff+4);
+ if( rc!=SQLITE_OK ) return rc;
+ rc = write32bits(pPager->jfd, iOff+pPager->pageSize+4, cksum);
+ if( rc!=SQLITE_OK ) return rc;
+
+ IOTRACE(("JOUT %p %d %lld %d\n", pPager, pPg->pgno,
+ pPager->journalOff, pPager->pageSize));
+ PAGER_INCR(sqlite3_pager_writej_count);
+ PAGERTRACE(("JOURNAL %d page %d needSync=%d hash(%08x)\n",
+ PAGERID(pPager), pPg->pgno,
+ ((pPg->flags&PGHDR_NEED_SYNC)?1:0), pager_pagehash(pPg)));
+
+ pPager->journalOff += 8 + pPager->pageSize;
+ pPager->nRec++;
+ assert( pPager->pInJournal!=0 );
+ rc = sqlite3BitvecSet(pPager->pInJournal, pPg->pgno);
+ testcase( rc==SQLITE_NOMEM );
+ assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
+ rc |= addToSavepointBitvecs(pPager, pPg->pgno);
+ assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
+ return rc;
+}
+
+/*
+** Mark a single data page as writeable. The page is written into the
+** main journal or sub-journal as required. If the page is written into
+** one of the journals, the corresponding bit is set in the
+** Pager.pInJournal bitvec and the PagerSavepoint.pInSavepoint bitvecs
+** of any open savepoints as appropriate.
+*/
+static int pager_write(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ int rc = SQLITE_OK;
+
+ /* This routine is not called unless a write-transaction has already
+ ** been started. The journal file may or may not be open at this point.
+ ** It is never called in the ERROR state.
+ */
+ assert( pPager->eState==PAGER_WRITER_LOCKED
+ || pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->errCode==0 );
+ assert( pPager->readOnly==0 );
+ CHECK_PAGE(pPg);
+
+ /* The journal file needs to be opened. Higher level routines have already
+ ** obtained the necessary locks to begin the write-transaction, but the
+ ** rollback journal might not yet be open. Open it now if this is the case.
+ **
+ ** This is done before calling sqlite3PcacheMakeDirty() on the page.
+ ** Otherwise, if it were done after calling sqlite3PcacheMakeDirty(), then
+ ** an error might occur and the pager would end up in WRITER_LOCKED state
+ ** with pages marked as dirty in the cache.
+ */
+ if( pPager->eState==PAGER_WRITER_LOCKED ){
+ rc = pager_open_journal(pPager);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
+ assert( assert_pager_state(pPager) );
+
+ /* Mark the page that is about to be modified as dirty. */
+ sqlite3PcacheMakeDirty(pPg);
+
+ /* If a rollback journal is in use, them make sure the page that is about
+ ** to change is in the rollback journal, or if the page is a new page off
+ ** then end of the file, make sure it is marked as PGHDR_NEED_SYNC.
+ */
+ assert( (pPager->pInJournal!=0) == isOpen(pPager->jfd) );
+ if( pPager->pInJournal!=0
+ && sqlite3BitvecTestNotNull(pPager->pInJournal, pPg->pgno)==0
+ ){
+ assert( pagerUseWal(pPager)==0 );
+ if( pPg->pgno<=pPager->dbOrigSize ){
+ rc = pagerAddPageToRollbackJournal(pPg);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ }else{
+ if( pPager->eState!=PAGER_WRITER_DBMOD ){
+ pPg->flags |= PGHDR_NEED_SYNC;
+ }
+ PAGERTRACE(("APPEND %d page %d needSync=%d\n",
+ PAGERID(pPager), pPg->pgno,
+ ((pPg->flags&PGHDR_NEED_SYNC)?1:0)));
+ }
+ }
+
+ /* The PGHDR_DIRTY bit is set above when the page was added to the dirty-list
+ ** and before writing the page into the rollback journal. Wait until now,
+ ** after the page has been successfully journalled, before setting the
+ ** PGHDR_WRITEABLE bit that indicates that the page can be safely modified.
+ */
+ pPg->flags |= PGHDR_WRITEABLE;
+
+ /* If the statement journal is open and the page is not in it,
+ ** then write the page into the statement journal.
+ */
+ if( pPager->nSavepoint>0 ){
+ rc = subjournalPageIfRequired(pPg);
+ }
+
+ /* Update the database size and return. */
+ if( pPager->dbSizepgno ){
+ pPager->dbSize = pPg->pgno;
+ }
+ return rc;
+}
+
+/*
+** This is a variant of sqlite3PagerWrite() that runs when the sector size
+** is larger than the page size. SQLite makes the (reasonable) assumption that
+** all bytes of a sector are written together by hardware. Hence, all bytes of
+** a sector need to be journalled in case of a power loss in the middle of
+** a write.
+**
+** Usually, the sector size is less than or equal to the page size, in which
+** case pages can be individually written. This routine only runs in the
+** exceptional case where the page size is smaller than the sector size.
+*/
+static SQLITE_NOINLINE int pagerWriteLargeSector(PgHdr *pPg){
+ int rc = SQLITE_OK; /* Return code */
+ Pgno nPageCount; /* Total number of pages in database file */
+ Pgno pg1; /* First page of the sector pPg is located on. */
+ int nPage = 0; /* Number of pages starting at pg1 to journal */
+ int ii; /* Loop counter */
+ int needSync = 0; /* True if any page has PGHDR_NEED_SYNC */
+ Pager *pPager = pPg->pPager; /* The pager that owns pPg */
+ Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);
+
+ /* Set the doNotSpill NOSYNC bit to 1. This is because we cannot allow
+ ** a journal header to be written between the pages journaled by
+ ** this function.
+ */
+ assert( !MEMDB );
+ assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)==0 );
+ pPager->doNotSpill |= SPILLFLAG_NOSYNC;
+
+ /* This trick assumes that both the page-size and sector-size are
+ ** an integer power of 2. It sets variable pg1 to the identifier
+ ** of the first page of the sector pPg is located on.
+ */
+ pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1;
+
+ nPageCount = pPager->dbSize;
+ if( pPg->pgno>nPageCount ){
+ nPage = (pPg->pgno - pg1)+1;
+ }else if( (pg1+nPagePerSector-1)>nPageCount ){
+ nPage = nPageCount+1-pg1;
+ }else{
+ nPage = nPagePerSector;
+ }
+ assert(nPage>0);
+ assert(pg1<=pPg->pgno);
+ assert((pg1+nPage)>pPg->pgno);
+
+ for(ii=0; iipgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){
+ if( pg!=PAGER_MJ_PGNO(pPager) ){
+ rc = sqlite3PagerGet(pPager, pg, &pPage, 0);
+ if( rc==SQLITE_OK ){
+ rc = pager_write(pPage);
+ if( pPage->flags&PGHDR_NEED_SYNC ){
+ needSync = 1;
+ }
+ sqlite3PagerUnrefNotNull(pPage);
+ }
+ }
+ }else if( (pPage = sqlite3PagerLookup(pPager, pg))!=0 ){
+ if( pPage->flags&PGHDR_NEED_SYNC ){
+ needSync = 1;
+ }
+ sqlite3PagerUnrefNotNull(pPage);
+ }
+ }
+
+ /* If the PGHDR_NEED_SYNC flag is set for any of the nPage pages
+ ** starting at pg1, then it needs to be set for all of them. Because
+ ** writing to any of these nPage pages may damage the others, the
+ ** journal file must contain sync()ed copies of all of them
+ ** before any of them can be written out to the database file.
+ */
+ if( rc==SQLITE_OK && needSync ){
+ assert( !MEMDB );
+ for(ii=0; iiflags |= PGHDR_NEED_SYNC;
+ sqlite3PagerUnrefNotNull(pPage);
+ }
+ }
+ }
+
+ assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)!=0 );
+ pPager->doNotSpill &= ~SPILLFLAG_NOSYNC;
+ return rc;
+}
+
+/*
+** Mark a data page as writeable. This routine must be called before
+** making changes to a page. The caller must check the return value
+** of this function and be careful not to change any page data unless
+** this routine returns SQLITE_OK.
+**
+** The difference between this function and pager_write() is that this
+** function also deals with the special case where 2 or more pages
+** fit on a single disk sector. In this case all co-resident pages
+** must have been written to the journal file before returning.
+**
+** If an error occurs, SQLITE_NOMEM or an IO error code is returned
+** as appropriate. Otherwise, SQLITE_OK.
+*/
+SQLITE_PRIVATE int sqlite3PagerWrite(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ assert( (pPg->flags & PGHDR_MMAP)==0 );
+ assert( pPager->eState>=PAGER_WRITER_LOCKED );
+ assert( assert_pager_state(pPager) );
+ if( (pPg->flags & PGHDR_WRITEABLE)!=0 && pPager->dbSize>=pPg->pgno ){
+ if( pPager->nSavepoint ) return subjournalPageIfRequired(pPg);
+ return SQLITE_OK;
+ }else if( pPager->errCode ){
+ return pPager->errCode;
+ }else if( pPager->sectorSize > (u32)pPager->pageSize ){
+ assert( pPager->tempFile==0 );
+ return pagerWriteLargeSector(pPg);
+ }else{
+ return pager_write(pPg);
+ }
+}
+
+/*
+** Return TRUE if the page given in the argument was previously passed
+** to sqlite3PagerWrite(). In other words, return TRUE if it is ok
+** to change the content of the page.
+*/
+#ifndef NDEBUG
+SQLITE_PRIVATE int sqlite3PagerIswriteable(DbPage *pPg){
+ return pPg->flags & PGHDR_WRITEABLE;
+}
+#endif
+
+/*
+** A call to this routine tells the pager that it is not necessary to
+** write the information on page pPg back to the disk, even though
+** that page might be marked as dirty. This happens, for example, when
+** the page has been added as a leaf of the freelist and so its
+** content no longer matters.
+**
+** The overlying software layer calls this routine when all of the data
+** on the given page is unused. The pager marks the page as clean so
+** that it does not get written to disk.
+**
+** Tests show that this optimization can quadruple the speed of large
+** DELETE operations.
+**
+** This optimization cannot be used with a temp-file, as the page may
+** have been dirty at the start of the transaction. In that case, if
+** memory pressure forces page pPg out of the cache, the data does need
+** to be written out to disk so that it may be read back in if the
+** current transaction is rolled back.
+*/
+SQLITE_PRIVATE void sqlite3PagerDontWrite(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ if( !pPager->tempFile && (pPg->flags&PGHDR_DIRTY) && pPager->nSavepoint==0 ){
+ PAGERTRACE(("DONT_WRITE page %d of %d\n", pPg->pgno, PAGERID(pPager)));
+ IOTRACE(("CLEAN %p %d\n", pPager, pPg->pgno))
+ pPg->flags |= PGHDR_DONT_WRITE;
+ pPg->flags &= ~PGHDR_WRITEABLE;
+ testcase( pPg->flags & PGHDR_NEED_SYNC );
+ pager_set_pagehash(pPg);
+ }
+}
+
+/*
+** This routine is called to increment the value of the database file
+** change-counter, stored as a 4-byte big-endian integer starting at
+** byte offset 24 of the pager file. The secondary change counter at
+** 92 is also updated, as is the SQLite version number at offset 96.
+**
+** But this only happens if the pPager->changeCountDone flag is false.
+** To avoid excess churning of page 1, the update only happens once.
+** See also the pager_write_changecounter() routine that does an
+** unconditional update of the change counters.
+**
+** If the isDirectMode flag is zero, then this is done by calling
+** sqlite3PagerWrite() on page 1, then modifying the contents of the
+** page data. In this case the file will be updated when the current
+** transaction is committed.
+**
+** The isDirectMode flag may only be non-zero if the library was compiled
+** with the SQLITE_ENABLE_ATOMIC_WRITE macro defined. In this case,
+** if isDirect is non-zero, then the database file is updated directly
+** by writing an updated version of page 1 using a call to the
+** sqlite3OsWrite() function.
+*/
+static int pager_incr_changecounter(Pager *pPager, int isDirectMode){
+ int rc = SQLITE_OK;
+
+ assert( pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ );
+ assert( assert_pager_state(pPager) );
+
+ /* Declare and initialize constant integer 'isDirect'. If the
+ ** atomic-write optimization is enabled in this build, then isDirect
+ ** is initialized to the value passed as the isDirectMode parameter
+ ** to this function. Otherwise, it is always set to zero.
+ **
+ ** The idea is that if the atomic-write optimization is not
+ ** enabled at compile time, the compiler can omit the tests of
+ ** 'isDirect' below, as well as the block enclosed in the
+ ** "if( isDirect )" condition.
+ */
+#ifndef SQLITE_ENABLE_ATOMIC_WRITE
+# define DIRECT_MODE 0
+ assert( isDirectMode==0 );
+ UNUSED_PARAMETER(isDirectMode);
+#else
+# define DIRECT_MODE isDirectMode
+#endif
+
+ if( !pPager->changeCountDone && ALWAYS(pPager->dbSize>0) ){
+ PgHdr *pPgHdr; /* Reference to page 1 */
+
+ assert( !pPager->tempFile && isOpen(pPager->fd) );
+
+ /* Open page 1 of the file for writing. */
+ rc = sqlite3PagerGet(pPager, 1, &pPgHdr, 0);
+ assert( pPgHdr==0 || rc==SQLITE_OK );
+
+ /* If page one was fetched successfully, and this function is not
+ ** operating in direct-mode, make page 1 writable. When not in
+ ** direct mode, page 1 is always held in cache and hence the PagerGet()
+ ** above is always successful - hence the ALWAYS on rc==SQLITE_OK.
+ */
+ if( !DIRECT_MODE && ALWAYS(rc==SQLITE_OK) ){
+ rc = sqlite3PagerWrite(pPgHdr);
+ }
+
+ if( rc==SQLITE_OK ){
+ /* Actually do the update of the change counter */
+ pager_write_changecounter(pPgHdr);
+
+ /* If running in direct mode, write the contents of page 1 to the file. */
+ if( DIRECT_MODE ){
+ const void *zBuf;
+ assert( pPager->dbFileSize>0 );
+ CODEC2(pPager, pPgHdr->pData, 1, 6, rc=SQLITE_NOMEM_BKPT, zBuf);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsWrite(pPager->fd, zBuf, pPager->pageSize, 0);
+ pPager->aStat[PAGER_STAT_WRITE]++;
+ }
+ if( rc==SQLITE_OK ){
+ /* Update the pager's copy of the change-counter. Otherwise, the
+ ** next time a read transaction is opened the cache will be
+ ** flushed (as the change-counter values will not match). */
+ const void *pCopy = (const void *)&((const char *)zBuf)[24];
+ memcpy(&pPager->dbFileVers, pCopy, sizeof(pPager->dbFileVers));
+ pPager->changeCountDone = 1;
+ }
+ }else{
+ pPager->changeCountDone = 1;
+ }
+ }
+
+ /* Release the page reference. */
+ sqlite3PagerUnref(pPgHdr);
+ }
+ return rc;
+}
+
+/*
+** Sync the database file to disk. This is a no-op for in-memory databases
+** or pages with the Pager.noSync flag set.
+**
+** If successful, or if called on a pager for which it is a no-op, this
+** function returns SQLITE_OK. Otherwise, an IO error code is returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager, const char *zMaster){
+ int rc = SQLITE_OK;
+ void *pArg = (void*)zMaster;
+ rc = sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_SYNC, pArg);
+ if( rc==SQLITE_NOTFOUND ) rc = SQLITE_OK;
+ if( rc==SQLITE_OK && !pPager->noSync ){
+ assert( !MEMDB );
+ rc = sqlite3OsSync(pPager->fd, pPager->syncFlags);
+ }
+ return rc;
+}
+
+/*
+** This function may only be called while a write-transaction is active in
+** rollback. If the connection is in WAL mode, this call is a no-op.
+** Otherwise, if the connection does not already have an EXCLUSIVE lock on
+** the database file, an attempt is made to obtain one.
+**
+** If the EXCLUSIVE lock is already held or the attempt to obtain it is
+** successful, or the connection is in WAL mode, SQLITE_OK is returned.
+** Otherwise, either SQLITE_BUSY or an SQLITE_IOERR_XXX error code is
+** returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager *pPager){
+ int rc = pPager->errCode;
+ assert( assert_pager_state(pPager) );
+ if( rc==SQLITE_OK ){
+ assert( pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ || pPager->eState==PAGER_WRITER_LOCKED
+ );
+ assert( assert_pager_state(pPager) );
+ if( 0==pagerUseWal(pPager) ){
+ rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+ }
+ }
+ return rc;
+}
+
+/*
+** Sync the database file for the pager pPager. zMaster points to the name
+** of a master journal file that should be written into the individual
+** journal file. zMaster may be NULL, which is interpreted as no master
+** journal (a single database transaction).
+**
+** This routine ensures that:
+**
+** * The database file change-counter is updated,
+** * the journal is synced (unless the atomic-write optimization is used),
+** * all dirty pages are written to the database file,
+** * the database file is truncated (if required), and
+** * the database file synced.
+**
+** The only thing that remains to commit the transaction is to finalize
+** (delete, truncate or zero the first part of) the journal file (or
+** delete the master journal file if specified).
+**
+** Note that if zMaster==NULL, this does not overwrite a previous value
+** passed to an sqlite3PagerCommitPhaseOne() call.
+**
+** If the final parameter - noSync - is true, then the database file itself
+** is not synced. The caller must call sqlite3PagerSync() directly to
+** sync the database file before calling CommitPhaseTwo() to delete the
+** journal file in this case.
+*/
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(
+ Pager *pPager, /* Pager object */
+ const char *zMaster, /* If not NULL, the master journal name */
+ int noSync /* True to omit the xSync on the db file */
+){
+ int rc = SQLITE_OK; /* Return code */
+
+ assert( pPager->eState==PAGER_WRITER_LOCKED
+ || pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ || pPager->eState==PAGER_ERROR
+ );
+ assert( assert_pager_state(pPager) );
+
+ /* If a prior error occurred, report that error again. */
+ if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+ /* Provide the ability to easily simulate an I/O error during testing */
+ if( sqlite3FaultSim(400) ) return SQLITE_IOERR;
+
+ PAGERTRACE(("DATABASE SYNC: File=%s zMaster=%s nSize=%d\n",
+ pPager->zFilename, zMaster, pPager->dbSize));
+
+ /* If no database changes have been made, return early. */
+ if( pPager->eStatetempFile );
+ assert( isOpen(pPager->fd) || pPager->tempFile );
+ if( 0==pagerFlushOnCommit(pPager, 1) ){
+ /* If this is an in-memory db, or no pages have been written to, or this
+ ** function has already been called, it is mostly a no-op. However, any
+ ** backup in progress needs to be restarted. */
+ sqlite3BackupRestart(pPager->pBackup);
+ }else{
+ PgHdr *pList;
+ if( pagerUseWal(pPager) ){
+ PgHdr *pPageOne = 0;
+ pList = sqlite3PcacheDirtyList(pPager->pPCache);
+ if( pList==0 ){
+ /* Must have at least one page for the WAL commit flag.
+ ** Ticket [2d1a5c67dfc2363e44f29d9bbd57f] 2011-05-18 */
+ rc = sqlite3PagerGet(pPager, 1, &pPageOne, 0);
+ pList = pPageOne;
+ pList->pDirty = 0;
+ }
+ assert( rc==SQLITE_OK );
+ if( ALWAYS(pList) ){
+ rc = pagerWalFrames(pPager, pList, pPager->dbSize, 1);
+ }
+ sqlite3PagerUnref(pPageOne);
+ if( rc==SQLITE_OK ){
+ sqlite3PcacheCleanAll(pPager->pPCache);
+ }
+ }else{
+ /* The bBatch boolean is true if the batch-atomic-write commit method
+ ** should be used. No rollback journal is created if batch-atomic-write
+ ** is enabled.
+ */
+#ifdef SQLITE_ENABLE_BATCH_ATOMIC_WRITE
+ sqlite3_file *fd = pPager->fd;
+ int bBatch = zMaster==0 /* An SQLITE_IOCAP_BATCH_ATOMIC commit */
+ && (sqlite3OsDeviceCharacteristics(fd) & SQLITE_IOCAP_BATCH_ATOMIC)
+ && !pPager->noSync
+ && sqlite3JournalIsInMemory(pPager->jfd);
+#else
+# define bBatch 0
+#endif
+
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+ /* The following block updates the change-counter. Exactly how it
+ ** does this depends on whether or not the atomic-update optimization
+ ** was enabled at compile time, and if this transaction meets the
+ ** runtime criteria to use the operation:
+ **
+ ** * The file-system supports the atomic-write property for
+ ** blocks of size page-size, and
+ ** * This commit is not part of a multi-file transaction, and
+ ** * Exactly one page has been modified and store in the journal file.
+ **
+ ** If the optimization was not enabled at compile time, then the
+ ** pager_incr_changecounter() function is called to update the change
+ ** counter in 'indirect-mode'. If the optimization is compiled in but
+ ** is not applicable to this transaction, call sqlite3JournalCreate()
+ ** to make sure the journal file has actually been created, then call
+ ** pager_incr_changecounter() to update the change-counter in indirect
+ ** mode.
+ **
+ ** Otherwise, if the optimization is both enabled and applicable,
+ ** then call pager_incr_changecounter() to update the change-counter
+ ** in 'direct' mode. In this case the journal file will never be
+ ** created for this transaction.
+ */
+ if( bBatch==0 ){
+ PgHdr *pPg;
+ assert( isOpen(pPager->jfd)
+ || pPager->journalMode==PAGER_JOURNALMODE_OFF
+ || pPager->journalMode==PAGER_JOURNALMODE_WAL
+ );
+ if( !zMaster && isOpen(pPager->jfd)
+ && pPager->journalOff==jrnlBufferSize(pPager)
+ && pPager->dbSize>=pPager->dbOrigSize
+ && (!(pPg = sqlite3PcacheDirtyList(pPager->pPCache)) || 0==pPg->pDirty)
+ ){
+ /* Update the db file change counter via the direct-write method. The
+ ** following call will modify the in-memory representation of page 1
+ ** to include the updated change counter and then write page 1
+ ** directly to the database file. Because of the atomic-write
+ ** property of the host file-system, this is safe.
+ */
+ rc = pager_incr_changecounter(pPager, 1);
+ }else{
+ rc = sqlite3JournalCreate(pPager->jfd);
+ if( rc==SQLITE_OK ){
+ rc = pager_incr_changecounter(pPager, 0);
+ }
+ }
+ }
+#else /* SQLITE_ENABLE_ATOMIC_WRITE */
+#ifdef SQLITE_ENABLE_BATCH_ATOMIC_WRITE
+ if( zMaster ){
+ rc = sqlite3JournalCreate(pPager->jfd);
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+ assert( bBatch==0 );
+ }
+#endif
+ rc = pager_incr_changecounter(pPager, 0);
+#endif /* !SQLITE_ENABLE_ATOMIC_WRITE */
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+ /* Write the master journal name into the journal file. If a master
+ ** journal file name has already been written to the journal file,
+ ** or if zMaster is NULL (no master journal), then this call is a no-op.
+ */
+ rc = writeMasterJournal(pPager, zMaster);
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+ /* Sync the journal file and write all dirty pages to the database.
+ ** If the atomic-update optimization is being used, this sync will not
+ ** create the journal file or perform any real IO.
+ **
+ ** Because the change-counter page was just modified, unless the
+ ** atomic-update optimization is used it is almost certain that the
+ ** journal requires a sync here. However, in locking_mode=exclusive
+ ** on a system under memory pressure it is just possible that this is
+ ** not the case. In this case it is likely enough that the redundant
+ ** xSync() call will be changed to a no-op by the OS anyhow.
+ */
+ rc = syncJournal(pPager, 0);
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+ pList = sqlite3PcacheDirtyList(pPager->pPCache);
+#ifdef SQLITE_ENABLE_BATCH_ATOMIC_WRITE
+ if( bBatch ){
+ rc = sqlite3OsFileControl(fd, SQLITE_FCNTL_BEGIN_ATOMIC_WRITE, 0);
+ if( rc==SQLITE_OK ){
+ rc = pager_write_pagelist(pPager, pList);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsFileControl(fd, SQLITE_FCNTL_COMMIT_ATOMIC_WRITE, 0);
+ }
+ if( rc!=SQLITE_OK ){
+ sqlite3OsFileControlHint(fd, SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE, 0);
+ }
+ }
+
+ if( (rc&0xFF)==SQLITE_IOERR && rc!=SQLITE_IOERR_NOMEM ){
+ rc = sqlite3JournalCreate(pPager->jfd);
+ if( rc!=SQLITE_OK ){
+ sqlite3OsClose(pPager->jfd);
+ goto commit_phase_one_exit;
+ }
+ bBatch = 0;
+ }else{
+ sqlite3OsClose(pPager->jfd);
+ }
+ }
+#endif /* SQLITE_ENABLE_BATCH_ATOMIC_WRITE */
+
+ if( bBatch==0 ){
+ rc = pager_write_pagelist(pPager, pList);
+ }
+ if( rc!=SQLITE_OK ){
+ assert( rc!=SQLITE_IOERR_BLOCKED );
+ goto commit_phase_one_exit;
+ }
+ sqlite3PcacheCleanAll(pPager->pPCache);
+
+ /* If the file on disk is smaller than the database image, use
+ ** pager_truncate to grow the file here. This can happen if the database
+ ** image was extended as part of the current transaction and then the
+ ** last page in the db image moved to the free-list. In this case the
+ ** last page is never written out to disk, leaving the database file
+ ** undersized. Fix this now if it is the case. */
+ if( pPager->dbSize>pPager->dbFileSize ){
+ Pgno nNew = pPager->dbSize - (pPager->dbSize==PAGER_MJ_PGNO(pPager));
+ assert( pPager->eState==PAGER_WRITER_DBMOD );
+ rc = pager_truncate(pPager, nNew);
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+ }
+
+ /* Finally, sync the database file. */
+ if( !noSync ){
+ rc = sqlite3PagerSync(pPager, zMaster);
+ }
+ IOTRACE(("DBSYNC %p\n", pPager))
+ }
+ }
+
+commit_phase_one_exit:
+ if( rc==SQLITE_OK && !pagerUseWal(pPager) ){
+ pPager->eState = PAGER_WRITER_FINISHED;
+ }
+ return rc;
+}
+
+
+/*
+** When this function is called, the database file has been completely
+** updated to reflect the changes made by the current transaction and
+** synced to disk. The journal file still exists in the file-system
+** though, and if a failure occurs at this point it will eventually
+** be used as a hot-journal and the current transaction rolled back.
+**
+** This function finalizes the journal file, either by deleting,
+** truncating or partially zeroing it, so that it cannot be used
+** for hot-journal rollback. Once this is done the transaction is
+** irrevocably committed.
+**
+** If an error occurs, an IO error code is returned and the pager
+** moves into the error state. Otherwise, SQLITE_OK is returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+
+ /* This routine should not be called if a prior error has occurred.
+ ** But if (due to a coding error elsewhere in the system) it does get
+ ** called, just return the same error code without doing anything. */
+ if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+ assert( pPager->eState==PAGER_WRITER_LOCKED
+ || pPager->eState==PAGER_WRITER_FINISHED
+ || (pagerUseWal(pPager) && pPager->eState==PAGER_WRITER_CACHEMOD)
+ );
+ assert( assert_pager_state(pPager) );
+
+ /* An optimization. If the database was not actually modified during
+ ** this transaction, the pager is running in exclusive-mode and is
+ ** using persistent journals, then this function is a no-op.
+ **
+ ** The start of the journal file currently contains a single journal
+ ** header with the nRec field set to 0. If such a journal is used as
+ ** a hot-journal during hot-journal rollback, 0 changes will be made
+ ** to the database file. So there is no need to zero the journal
+ ** header. Since the pager is in exclusive mode, there is no need
+ ** to drop any locks either.
+ */
+ if( pPager->eState==PAGER_WRITER_LOCKED
+ && pPager->exclusiveMode
+ && pPager->journalMode==PAGER_JOURNALMODE_PERSIST
+ ){
+ assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) || !pPager->journalOff );
+ pPager->eState = PAGER_READER;
+ return SQLITE_OK;
+ }
+
+ PAGERTRACE(("COMMIT %d\n", PAGERID(pPager)));
+ pPager->iDataVersion++;
+ rc = pager_end_transaction(pPager, pPager->setMaster, 1);
+ return pager_error(pPager, rc);
+}
+
+/*
+** If a write transaction is open, then all changes made within the
+** transaction are reverted and the current write-transaction is closed.
+** The pager falls back to PAGER_READER state if successful, or PAGER_ERROR
+** state if an error occurs.
+**
+** If the pager is already in PAGER_ERROR state when this function is called,
+** it returns Pager.errCode immediately. No work is performed in this case.
+**
+** Otherwise, in rollback mode, this function performs two functions:
+**
+** 1) It rolls back the journal file, restoring all database file and
+** in-memory cache pages to the state they were in when the transaction
+** was opened, and
+**
+** 2) It finalizes the journal file, so that it is not used for hot
+** rollback at any point in the future.
+**
+** Finalization of the journal file (task 2) is only performed if the
+** rollback is successful.
+**
+** In WAL mode, all cache-entries containing data modified within the
+** current transaction are either expelled from the cache or reverted to
+** their pre-transaction state by re-reading data from the database or
+** WAL files. The WAL transaction is then closed.
+*/
+SQLITE_PRIVATE int sqlite3PagerRollback(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+ PAGERTRACE(("ROLLBACK %d\n", PAGERID(pPager)));
+
+ /* PagerRollback() is a no-op if called in READER or OPEN state. If
+ ** the pager is already in the ERROR state, the rollback is not
+ ** attempted here. Instead, the error code is returned to the caller.
+ */
+ assert( assert_pager_state(pPager) );
+ if( pPager->eState==PAGER_ERROR ) return pPager->errCode;
+ if( pPager->eState<=PAGER_READER ) return SQLITE_OK;
+
+ if( pagerUseWal(pPager) ){
+ int rc2;
+ rc = sqlite3PagerSavepoint(pPager, SAVEPOINT_ROLLBACK, -1);
+ rc2 = pager_end_transaction(pPager, pPager->setMaster, 0);
+ if( rc==SQLITE_OK ) rc = rc2;
+ }else if( !isOpen(pPager->jfd) || pPager->eState==PAGER_WRITER_LOCKED ){
+ int eState = pPager->eState;
+ rc = pager_end_transaction(pPager, 0, 0);
+ if( !MEMDB && eState>PAGER_WRITER_LOCKED ){
+ /* This can happen using journal_mode=off. Move the pager to the error
+ ** state to indicate that the contents of the cache may not be trusted.
+ ** Any active readers will get SQLITE_ABORT.
+ */
+ pPager->errCode = SQLITE_ABORT;
+ pPager->eState = PAGER_ERROR;
+ setGetterMethod(pPager);
+ return rc;
+ }
+ }else{
+ rc = pager_playback(pPager, 0);
+ }
+
+ assert( pPager->eState==PAGER_READER || rc!=SQLITE_OK );
+ assert( rc==SQLITE_OK || rc==SQLITE_FULL || rc==SQLITE_CORRUPT
+ || rc==SQLITE_NOMEM || (rc&0xFF)==SQLITE_IOERR
+ || rc==SQLITE_CANTOPEN
+ );
+
+ /* If an error occurs during a ROLLBACK, we can no longer trust the pager
+ ** cache. So call pager_error() on the way out to make any error persistent.
+ */
+ return pager_error(pPager, rc);
+}
+
+/*
+** Return TRUE if the database file is opened read-only. Return FALSE
+** if the database is (in theory) writable.
+*/
+SQLITE_PRIVATE u8 sqlite3PagerIsreadonly(Pager *pPager){
+ return pPager->readOnly;
+}
+
+#ifdef SQLITE_DEBUG
+/*
+** Return the sum of the reference counts for all pages held by pPager.
+*/
+SQLITE_PRIVATE int sqlite3PagerRefcount(Pager *pPager){
+ return sqlite3PcacheRefCount(pPager->pPCache);
+}
+#endif
+
+/*
+** Return the approximate number of bytes of memory currently
+** used by the pager and its associated cache.
+*/
+SQLITE_PRIVATE int sqlite3PagerMemUsed(Pager *pPager){
+ int perPageSize = pPager->pageSize + pPager->nExtra + sizeof(PgHdr)
+ + 5*sizeof(void*);
+ return perPageSize*sqlite3PcachePagecount(pPager->pPCache)
+ + sqlite3MallocSize(pPager)
+ + pPager->pageSize;
+}
+
+/*
+** Return the number of references to the specified page.
+*/
+SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage *pPage){
+ return sqlite3PcachePageRefcount(pPage);
+}
+
+#ifdef SQLITE_TEST
+/*
+** This routine is used for testing and analysis only.
+*/
+SQLITE_PRIVATE int *sqlite3PagerStats(Pager *pPager){
+ static int a[11];
+ a[0] = sqlite3PcacheRefCount(pPager->pPCache);
+ a[1] = sqlite3PcachePagecount(pPager->pPCache);
+ a[2] = sqlite3PcacheGetCachesize(pPager->pPCache);
+ a[3] = pPager->eState==PAGER_OPEN ? -1 : (int) pPager->dbSize;
+ a[4] = pPager->eState;
+ a[5] = pPager->errCode;
+ a[6] = pPager->aStat[PAGER_STAT_HIT];
+ a[7] = pPager->aStat[PAGER_STAT_MISS];
+ a[8] = 0; /* Used to be pPager->nOvfl */
+ a[9] = pPager->nRead;
+ a[10] = pPager->aStat[PAGER_STAT_WRITE];
+ return a;
+}
+#endif
+
+/*
+** Parameter eStat must be one of SQLITE_DBSTATUS_CACHE_HIT, _MISS, _WRITE,
+** or _WRITE+1. The SQLITE_DBSTATUS_CACHE_WRITE+1 case is a translation
+** of SQLITE_DBSTATUS_CACHE_SPILL. The _SPILL case is not contiguous because
+** it was added later.
+**
+** Before returning, *pnVal is incremented by the
+** current cache hit or miss count, according to the value of eStat. If the
+** reset parameter is non-zero, the cache hit or miss count is zeroed before
+** returning.
+*/
+SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *pPager, int eStat, int reset, int *pnVal){
+
+ assert( eStat==SQLITE_DBSTATUS_CACHE_HIT
+ || eStat==SQLITE_DBSTATUS_CACHE_MISS
+ || eStat==SQLITE_DBSTATUS_CACHE_WRITE
+ || eStat==SQLITE_DBSTATUS_CACHE_WRITE+1
+ );
+
+ assert( SQLITE_DBSTATUS_CACHE_HIT+1==SQLITE_DBSTATUS_CACHE_MISS );
+ assert( SQLITE_DBSTATUS_CACHE_HIT+2==SQLITE_DBSTATUS_CACHE_WRITE );
+ assert( PAGER_STAT_HIT==0 && PAGER_STAT_MISS==1
+ && PAGER_STAT_WRITE==2 && PAGER_STAT_SPILL==3 );
+
+ eStat -= SQLITE_DBSTATUS_CACHE_HIT;
+ *pnVal += pPager->aStat[eStat];
+ if( reset ){
+ pPager->aStat[eStat] = 0;
+ }
+}
+
+/*
+** Return true if this is an in-memory or temp-file backed pager.
+*/
+SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager *pPager){
+ return pPager->tempFile;
+}
+
+/*
+** Check that there are at least nSavepoint savepoints open. If there are
+** currently less than nSavepoints open, then open one or more savepoints
+** to make up the difference. If the number of savepoints is already
+** equal to nSavepoint, then this function is a no-op.
+**
+** If a memory allocation fails, SQLITE_NOMEM is returned. If an error
+** occurs while opening the sub-journal file, then an IO error code is
+** returned. Otherwise, SQLITE_OK.
+*/
+static SQLITE_NOINLINE int pagerOpenSavepoint(Pager *pPager, int nSavepoint){
+ int rc = SQLITE_OK; /* Return code */
+ int nCurrent = pPager->nSavepoint; /* Current number of savepoints */
+ int ii; /* Iterator variable */
+ PagerSavepoint *aNew; /* New Pager.aSavepoint array */
+
+ assert( pPager->eState>=PAGER_WRITER_LOCKED );
+ assert( assert_pager_state(pPager) );
+ assert( nSavepoint>nCurrent && pPager->useJournal );
+
+ /* Grow the Pager.aSavepoint array using realloc(). Return SQLITE_NOMEM
+ ** if the allocation fails. Otherwise, zero the new portion in case a
+ ** malloc failure occurs while populating it in the for(...) loop below.
+ */
+ aNew = (PagerSavepoint *)sqlite3Realloc(
+ pPager->aSavepoint, sizeof(PagerSavepoint)*nSavepoint
+ );
+ if( !aNew ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ memset(&aNew[nCurrent], 0, (nSavepoint-nCurrent) * sizeof(PagerSavepoint));
+ pPager->aSavepoint = aNew;
+
+ /* Populate the PagerSavepoint structures just allocated. */
+ for(ii=nCurrent; iidbSize;
+ if( isOpen(pPager->jfd) && pPager->journalOff>0 ){
+ aNew[ii].iOffset = pPager->journalOff;
+ }else{
+ aNew[ii].iOffset = JOURNAL_HDR_SZ(pPager);
+ }
+ aNew[ii].iSubRec = pPager->nSubRec;
+ aNew[ii].pInSavepoint = sqlite3BitvecCreate(pPager->dbSize);
+ if( !aNew[ii].pInSavepoint ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ if( pagerUseWal(pPager) ){
+ sqlite3WalSavepoint(pPager->pWal, aNew[ii].aWalData);
+ }
+ pPager->nSavepoint = ii+1;
+ }
+ assert( pPager->nSavepoint==nSavepoint );
+ assertTruncateConstraint(pPager);
+ return rc;
+}
+SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int nSavepoint){
+ assert( pPager->eState>=PAGER_WRITER_LOCKED );
+ assert( assert_pager_state(pPager) );
+
+ if( nSavepoint>pPager->nSavepoint && pPager->useJournal ){
+ return pagerOpenSavepoint(pPager, nSavepoint);
+ }else{
+ return SQLITE_OK;
+ }
+}
+
+
+/*
+** This function is called to rollback or release (commit) a savepoint.
+** The savepoint to release or rollback need not be the most recently
+** created savepoint.
+**
+** Parameter op is always either SAVEPOINT_ROLLBACK or SAVEPOINT_RELEASE.
+** If it is SAVEPOINT_RELEASE, then release and destroy the savepoint with
+** index iSavepoint. If it is SAVEPOINT_ROLLBACK, then rollback all changes
+** that have occurred since the specified savepoint was created.
+**
+** The savepoint to rollback or release is identified by parameter
+** iSavepoint. A value of 0 means to operate on the outermost savepoint
+** (the first created). A value of (Pager.nSavepoint-1) means operate
+** on the most recently created savepoint. If iSavepoint is greater than
+** (Pager.nSavepoint-1), then this function is a no-op.
+**
+** If a negative value is passed to this function, then the current
+** transaction is rolled back. This is different to calling
+** sqlite3PagerRollback() because this function does not terminate
+** the transaction or unlock the database, it just restores the
+** contents of the database to its original state.
+**
+** In any case, all savepoints with an index greater than iSavepoint
+** are destroyed. If this is a release operation (op==SAVEPOINT_RELEASE),
+** then savepoint iSavepoint is also destroyed.
+**
+** This function may return SQLITE_NOMEM if a memory allocation fails,
+** or an IO error code if an IO error occurs while rolling back a
+** savepoint. If no errors occur, SQLITE_OK is returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint){
+ int rc = pPager->errCode;
+
+#ifdef SQLITE_ENABLE_ZIPVFS
+ if( op==SAVEPOINT_RELEASE ) rc = SQLITE_OK;
+#endif
+
+ assert( op==SAVEPOINT_RELEASE || op==SAVEPOINT_ROLLBACK );
+ assert( iSavepoint>=0 || op==SAVEPOINT_ROLLBACK );
+
+ if( rc==SQLITE_OK && iSavepointnSavepoint ){
+ int ii; /* Iterator variable */
+ int nNew; /* Number of remaining savepoints after this op. */
+
+ /* Figure out how many savepoints will still be active after this
+ ** operation. Store this value in nNew. Then free resources associated
+ ** with any savepoints that are destroyed by this operation.
+ */
+ nNew = iSavepoint + (( op==SAVEPOINT_RELEASE ) ? 0 : 1);
+ for(ii=nNew; iinSavepoint; ii++){
+ sqlite3BitvecDestroy(pPager->aSavepoint[ii].pInSavepoint);
+ }
+ pPager->nSavepoint = nNew;
+
+ /* If this is a release of the outermost savepoint, truncate
+ ** the sub-journal to zero bytes in size. */
+ if( op==SAVEPOINT_RELEASE ){
+ if( nNew==0 && isOpen(pPager->sjfd) ){
+ /* Only truncate if it is an in-memory sub-journal. */
+ if( sqlite3JournalIsInMemory(pPager->sjfd) ){
+ rc = sqlite3OsTruncate(pPager->sjfd, 0);
+ assert( rc==SQLITE_OK );
+ }
+ pPager->nSubRec = 0;
+ }
+ }
+ /* Else this is a rollback operation, playback the specified savepoint.
+ ** If this is a temp-file, it is possible that the journal file has
+ ** not yet been opened. In this case there have been no changes to
+ ** the database file, so the playback operation can be skipped.
+ */
+ else if( pagerUseWal(pPager) || isOpen(pPager->jfd) ){
+ PagerSavepoint *pSavepoint = (nNew==0)?0:&pPager->aSavepoint[nNew-1];
+ rc = pagerPlaybackSavepoint(pPager, pSavepoint);
+ assert(rc!=SQLITE_DONE);
+ }
+
+#ifdef SQLITE_ENABLE_ZIPVFS
+ /* If the cache has been modified but the savepoint cannot be rolled
+ ** back journal_mode=off, put the pager in the error state. This way,
+ ** if the VFS used by this pager includes ZipVFS, the entire transaction
+ ** can be rolled back at the ZipVFS level. */
+ else if(
+ pPager->journalMode==PAGER_JOURNALMODE_OFF
+ && pPager->eState>=PAGER_WRITER_CACHEMOD
+ ){
+ pPager->errCode = SQLITE_ABORT;
+ pPager->eState = PAGER_ERROR;
+ setGetterMethod(pPager);
+ }
+#endif
+ }
+
+ return rc;
+}
+
+/*
+** Return the full pathname of the database file.
+**
+** Except, if the pager is in-memory only, then return an empty string if
+** nullIfMemDb is true. This routine is called with nullIfMemDb==1 when
+** used to report the filename to the user, for compatibility with legacy
+** behavior. But when the Btree needs to know the filename for matching to
+** shared cache, it uses nullIfMemDb==0 so that in-memory databases can
+** participate in shared-cache.
+*/
+SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager *pPager, int nullIfMemDb){
+ return (nullIfMemDb && pPager->memDb) ? "" : pPager->zFilename;
+}
+
+/*
+** Return the VFS structure for the pager.
+*/
+SQLITE_PRIVATE sqlite3_vfs *sqlite3PagerVfs(Pager *pPager){
+ return pPager->pVfs;
+}
+
+/*
+** Return the file handle for the database file associated
+** with the pager. This might return NULL if the file has
+** not yet been opened.
+*/
+SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager *pPager){
+ return pPager->fd;
+}
+
+#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
+/*
+** Reset the lock timeout for pager.
+*/
+SQLITE_PRIVATE void sqlite3PagerResetLockTimeout(Pager *pPager){
+ int x = 0;
+ sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_LOCK_TIMEOUT, &x);
+}
+#endif
+
+/*
+** Return the file handle for the journal file (if it exists).
+** This will be either the rollback journal or the WAL file.
+*/
+SQLITE_PRIVATE sqlite3_file *sqlite3PagerJrnlFile(Pager *pPager){
+#if SQLITE_OMIT_WAL
+ return pPager->jfd;
+#else
+ return pPager->pWal ? sqlite3WalFile(pPager->pWal) : pPager->jfd;
+#endif
+}
+
+/*
+** Return the full pathname of the journal file.
+*/
+SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager *pPager){
+ return pPager->zJournal;
+}
+
+#ifdef SQLITE_HAS_CODEC
+/*
+** Set or retrieve the codec for this pager
+*/
+SQLITE_PRIVATE void sqlite3PagerSetCodec(
+ Pager *pPager,
+ void *(*xCodec)(void*,void*,Pgno,int),
+ void (*xCodecSizeChng)(void*,int,int),
+ void (*xCodecFree)(void*),
+ void *pCodec
+){
+ if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
+ pPager->xCodec = pPager->memDb ? 0 : xCodec;
+ pPager->xCodecSizeChng = xCodecSizeChng;
+ pPager->xCodecFree = xCodecFree;
+ pPager->pCodec = pCodec;
+ setGetterMethod(pPager);
+ pagerReportSize(pPager);
+}
+SQLITE_PRIVATE void *sqlite3PagerGetCodec(Pager *pPager){
+ return pPager->pCodec;
+}
+
+/*
+** This function is called by the wal module when writing page content
+** into the log file.
+**
+** This function returns a pointer to a buffer containing the encrypted
+** page content. If a malloc fails, this function may return NULL.
+*/
+SQLITE_PRIVATE void *sqlite3PagerCodec(PgHdr *pPg){
+ void *aData = 0;
+ CODEC2(pPg->pPager, pPg->pData, pPg->pgno, 6, return 0, aData);
+ return aData;
+}
+
+/*
+** Return the current pager state
+*/
+SQLITE_PRIVATE int sqlite3PagerState(Pager *pPager){
+ return pPager->eState;
+}
+#endif /* SQLITE_HAS_CODEC */
+
+#ifndef SQLITE_OMIT_AUTOVACUUM
+/*
+** Move the page pPg to location pgno in the file.
+**
+** There must be no references to the page previously located at
+** pgno (which we call pPgOld) though that page is allowed to be
+** in cache. If the page previously located at pgno is not already
+** in the rollback journal, it is not put there by by this routine.
+**
+** References to the page pPg remain valid. Updating any
+** meta-data associated with pPg (i.e. data stored in the nExtra bytes
+** allocated along with the page) is the responsibility of the caller.
+**
+** A transaction must be active when this routine is called. It used to be
+** required that a statement transaction was not active, but this restriction
+** has been removed (CREATE INDEX needs to move a page when a statement
+** transaction is active).
+**
+** If the fourth argument, isCommit, is non-zero, then this page is being
+** moved as part of a database reorganization just before the transaction
+** is being committed. In this case, it is guaranteed that the database page
+** pPg refers to will not be written to again within this transaction.
+**
+** This function may return SQLITE_NOMEM or an IO error code if an error
+** occurs. Otherwise, it returns SQLITE_OK.
+*/
+SQLITE_PRIVATE int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){
+ PgHdr *pPgOld; /* The page being overwritten. */
+ Pgno needSyncPgno = 0; /* Old value of pPg->pgno, if sync is required */
+ int rc; /* Return code */
+ Pgno origPgno; /* The original page number */
+
+ assert( pPg->nRef>0 );
+ assert( pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ );
+ assert( assert_pager_state(pPager) );
+
+ /* In order to be able to rollback, an in-memory database must journal
+ ** the page we are moving from.
+ */
+ assert( pPager->tempFile || !MEMDB );
+ if( pPager->tempFile ){
+ rc = sqlite3PagerWrite(pPg);
+ if( rc ) return rc;
+ }
+
+ /* If the page being moved is dirty and has not been saved by the latest
+ ** savepoint, then save the current contents of the page into the
+ ** sub-journal now. This is required to handle the following scenario:
+ **
+ ** BEGIN;
+ **
+ ** SAVEPOINT one;
+ **
+ ** ROLLBACK TO one;
+ **
+ ** If page X were not written to the sub-journal here, it would not
+ ** be possible to restore its contents when the "ROLLBACK TO one"
+ ** statement were is processed.
+ **
+ ** subjournalPage() may need to allocate space to store pPg->pgno into
+ ** one or more savepoint bitvecs. This is the reason this function
+ ** may return SQLITE_NOMEM.
+ */
+ if( (pPg->flags & PGHDR_DIRTY)!=0
+ && SQLITE_OK!=(rc = subjournalPageIfRequired(pPg))
+ ){
+ return rc;
+ }
+
+ PAGERTRACE(("MOVE %d page %d (needSync=%d) moves to %d\n",
+ PAGERID(pPager), pPg->pgno, (pPg->flags&PGHDR_NEED_SYNC)?1:0, pgno));
+ IOTRACE(("MOVE %p %d %d\n", pPager, pPg->pgno, pgno))
+
+ /* If the journal needs to be sync()ed before page pPg->pgno can
+ ** be written to, store pPg->pgno in local variable needSyncPgno.
+ **
+ ** If the isCommit flag is set, there is no need to remember that
+ ** the journal needs to be sync()ed before database page pPg->pgno
+ ** can be written to. The caller has already promised not to write to it.
+ */
+ if( (pPg->flags&PGHDR_NEED_SYNC) && !isCommit ){
+ needSyncPgno = pPg->pgno;
+ assert( pPager->journalMode==PAGER_JOURNALMODE_OFF ||
+ pageInJournal(pPager, pPg) || pPg->pgno>pPager->dbOrigSize );
+ assert( pPg->flags&PGHDR_DIRTY );
+ }
+
+ /* If the cache contains a page with page-number pgno, remove it
+ ** from its hash chain. Also, if the PGHDR_NEED_SYNC flag was set for
+ ** page pgno before the 'move' operation, it needs to be retained
+ ** for the page moved there.
+ */
+ pPg->flags &= ~PGHDR_NEED_SYNC;
+ pPgOld = sqlite3PagerLookup(pPager, pgno);
+ assert( !pPgOld || pPgOld->nRef==1 );
+ if( pPgOld ){
+ pPg->flags |= (pPgOld->flags&PGHDR_NEED_SYNC);
+ if( pPager->tempFile ){
+ /* Do not discard pages from an in-memory database since we might
+ ** need to rollback later. Just move the page out of the way. */
+ sqlite3PcacheMove(pPgOld, pPager->dbSize+1);
+ }else{
+ sqlite3PcacheDrop(pPgOld);
+ }
+ }
+
+ origPgno = pPg->pgno;
+ sqlite3PcacheMove(pPg, pgno);
+ sqlite3PcacheMakeDirty(pPg);
+
+ /* For an in-memory database, make sure the original page continues
+ ** to exist, in case the transaction needs to roll back. Use pPgOld
+ ** as the original page since it has already been allocated.
+ */
+ if( pPager->tempFile && pPgOld ){
+ sqlite3PcacheMove(pPgOld, origPgno);
+ sqlite3PagerUnrefNotNull(pPgOld);
+ }
+
+ if( needSyncPgno ){
+ /* If needSyncPgno is non-zero, then the journal file needs to be
+ ** sync()ed before any data is written to database file page needSyncPgno.
+ ** Currently, no such page exists in the page-cache and the
+ ** "is journaled" bitvec flag has been set. This needs to be remedied by
+ ** loading the page into the pager-cache and setting the PGHDR_NEED_SYNC
+ ** flag.
+ **
+ ** If the attempt to load the page into the page-cache fails, (due
+ ** to a malloc() or IO failure), clear the bit in the pInJournal[]
+ ** array. Otherwise, if the page is loaded and written again in
+ ** this transaction, it may be written to the database file before
+ ** it is synced into the journal file. This way, it may end up in
+ ** the journal file twice, but that is not a problem.
+ */
+ PgHdr *pPgHdr;
+ rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr, 0);
+ if( rc!=SQLITE_OK ){
+ if( needSyncPgno<=pPager->dbOrigSize ){
+ assert( pPager->pTmpSpace!=0 );
+ sqlite3BitvecClear(pPager->pInJournal, needSyncPgno, pPager->pTmpSpace);
+ }
+ return rc;
+ }
+ pPgHdr->flags |= PGHDR_NEED_SYNC;
+ sqlite3PcacheMakeDirty(pPgHdr);
+ sqlite3PagerUnrefNotNull(pPgHdr);
+ }
+
+ return SQLITE_OK;
+}
+#endif
+
+/*
+** The page handle passed as the first argument refers to a dirty page
+** with a page number other than iNew. This function changes the page's
+** page number to iNew and sets the value of the PgHdr.flags field to
+** the value passed as the third parameter.
+*/
+SQLITE_PRIVATE void sqlite3PagerRekey(DbPage *pPg, Pgno iNew, u16 flags){
+ assert( pPg->pgno!=iNew );
+ pPg->flags = flags;
+ sqlite3PcacheMove(pPg, iNew);
+}
+
+/*
+** Return a pointer to the data for the specified page.
+*/
+SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *pPg){
+ assert( pPg->nRef>0 || pPg->pPager->memDb );
+ return pPg->pData;
+}
+
+/*
+** Return a pointer to the Pager.nExtra bytes of "extra" space
+** allocated along with the specified page.
+*/
+SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *pPg){
+ return pPg->pExtra;
+}
+
+/*
+** Get/set the locking-mode for this pager. Parameter eMode must be one
+** of PAGER_LOCKINGMODE_QUERY, PAGER_LOCKINGMODE_NORMAL or
+** PAGER_LOCKINGMODE_EXCLUSIVE. If the parameter is not _QUERY, then
+** the locking-mode is set to the value specified.
+**
+** The returned value is either PAGER_LOCKINGMODE_NORMAL or
+** PAGER_LOCKINGMODE_EXCLUSIVE, indicating the current (possibly updated)
+** locking-mode.
+*/
+SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *pPager, int eMode){
+ assert( eMode==PAGER_LOCKINGMODE_QUERY
+ || eMode==PAGER_LOCKINGMODE_NORMAL
+ || eMode==PAGER_LOCKINGMODE_EXCLUSIVE );
+ assert( PAGER_LOCKINGMODE_QUERY<0 );
+ assert( PAGER_LOCKINGMODE_NORMAL>=0 && PAGER_LOCKINGMODE_EXCLUSIVE>=0 );
+ assert( pPager->exclusiveMode || 0==sqlite3WalHeapMemory(pPager->pWal) );
+ if( eMode>=0 && !pPager->tempFile && !sqlite3WalHeapMemory(pPager->pWal) ){
+ pPager->exclusiveMode = (u8)eMode;
+ }
+ return (int)pPager->exclusiveMode;
+}
+
+/*
+** Set the journal-mode for this pager. Parameter eMode must be one of:
+**
+** PAGER_JOURNALMODE_DELETE
+** PAGER_JOURNALMODE_TRUNCATE
+** PAGER_JOURNALMODE_PERSIST
+** PAGER_JOURNALMODE_OFF
+** PAGER_JOURNALMODE_MEMORY
+** PAGER_JOURNALMODE_WAL
+**
+** The journalmode is set to the value specified if the change is allowed.
+** The change may be disallowed for the following reasons:
+**
+** * An in-memory database can only have its journal_mode set to _OFF
+** or _MEMORY.
+**
+** * Temporary databases cannot have _WAL journalmode.
+**
+** The returned indicate the current (possibly updated) journal-mode.
+*/
+SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *pPager, int eMode){
+ u8 eOld = pPager->journalMode; /* Prior journalmode */
+
+ /* The eMode parameter is always valid */
+ assert( eMode==PAGER_JOURNALMODE_DELETE
+ || eMode==PAGER_JOURNALMODE_TRUNCATE
+ || eMode==PAGER_JOURNALMODE_PERSIST
+ || eMode==PAGER_JOURNALMODE_OFF
+ || eMode==PAGER_JOURNALMODE_WAL
+ || eMode==PAGER_JOURNALMODE_MEMORY );
+
+ /* This routine is only called from the OP_JournalMode opcode, and
+ ** the logic there will never allow a temporary file to be changed
+ ** to WAL mode.
+ */
+ assert( pPager->tempFile==0 || eMode!=PAGER_JOURNALMODE_WAL );
+
+ /* Do allow the journalmode of an in-memory database to be set to
+ ** anything other than MEMORY or OFF
+ */
+ if( MEMDB ){
+ assert( eOld==PAGER_JOURNALMODE_MEMORY || eOld==PAGER_JOURNALMODE_OFF );
+ if( eMode!=PAGER_JOURNALMODE_MEMORY && eMode!=PAGER_JOURNALMODE_OFF ){
+ eMode = eOld;
+ }
+ }
+
+ if( eMode!=eOld ){
+
+ /* Change the journal mode. */
+ assert( pPager->eState!=PAGER_ERROR );
+ pPager->journalMode = (u8)eMode;
+
+ /* When transistioning from TRUNCATE or PERSIST to any other journal
+ ** mode except WAL, unless the pager is in locking_mode=exclusive mode,
+ ** delete the journal file.
+ */
+ assert( (PAGER_JOURNALMODE_TRUNCATE & 5)==1 );
+ assert( (PAGER_JOURNALMODE_PERSIST & 5)==1 );
+ assert( (PAGER_JOURNALMODE_DELETE & 5)==0 );
+ assert( (PAGER_JOURNALMODE_MEMORY & 5)==4 );
+ assert( (PAGER_JOURNALMODE_OFF & 5)==0 );
+ assert( (PAGER_JOURNALMODE_WAL & 5)==5 );
+
+ assert( isOpen(pPager->fd) || pPager->exclusiveMode );
+ if( !pPager->exclusiveMode && (eOld & 5)==1 && (eMode & 1)==0 ){
+
+ /* In this case we would like to delete the journal file. If it is
+ ** not possible, then that is not a problem. Deleting the journal file
+ ** here is an optimization only.
+ **
+ ** Before deleting the journal file, obtain a RESERVED lock on the
+ ** database file. This ensures that the journal file is not deleted
+ ** while it is in use by some other client.
+ */
+ sqlite3OsClose(pPager->jfd);
+ if( pPager->eLock>=RESERVED_LOCK ){
+ sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+ }else{
+ int rc = SQLITE_OK;
+ int state = pPager->eState;
+ assert( state==PAGER_OPEN || state==PAGER_READER );
+ if( state==PAGER_OPEN ){
+ rc = sqlite3PagerSharedLock(pPager);
+ }
+ if( pPager->eState==PAGER_READER ){
+ assert( rc==SQLITE_OK );
+ rc = pagerLockDb(pPager, RESERVED_LOCK);
+ }
+ if( rc==SQLITE_OK ){
+ sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+ }
+ if( rc==SQLITE_OK && state==PAGER_READER ){
+ pagerUnlockDb(pPager, SHARED_LOCK);
+ }else if( state==PAGER_OPEN ){
+ pager_unlock(pPager);
+ }
+ assert( state==pPager->eState );
+ }
+ }else if( eMode==PAGER_JOURNALMODE_OFF ){
+ sqlite3OsClose(pPager->jfd);
+ }
+ }
+
+ /* Return the new journal mode */
+ return (int)pPager->journalMode;
+}
+
+/*
+** Return the current journal mode.
+*/
+SQLITE_PRIVATE int sqlite3PagerGetJournalMode(Pager *pPager){
+ return (int)pPager->journalMode;
+}
+
+/*
+** Return TRUE if the pager is in a state where it is OK to change the
+** journalmode. Journalmode changes can only happen when the database
+** is unmodified.
+*/
+SQLITE_PRIVATE int sqlite3PagerOkToChangeJournalMode(Pager *pPager){
+ assert( assert_pager_state(pPager) );
+ if( pPager->eState>=PAGER_WRITER_CACHEMOD ) return 0;
+ if( NEVER(isOpen(pPager->jfd) && pPager->journalOff>0) ) return 0;
+ return 1;
+}
+
+/*
+** Get/set the size-limit used for persistent journal files.
+**
+** Setting the size limit to -1 means no limit is enforced.
+** An attempt to set a limit smaller than -1 is a no-op.
+*/
+SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *pPager, i64 iLimit){
+ if( iLimit>=-1 ){
+ pPager->journalSizeLimit = iLimit;
+ sqlite3WalLimit(pPager->pWal, iLimit);
+ }
+ return pPager->journalSizeLimit;
+}
+
+/*
+** Return a pointer to the pPager->pBackup variable. The backup module
+** in backup.c maintains the content of this variable. This module
+** uses it opaquely as an argument to sqlite3BackupRestart() and
+** sqlite3BackupUpdate() only.
+*/
+SQLITE_PRIVATE sqlite3_backup **sqlite3PagerBackupPtr(Pager *pPager){
+ return &pPager->pBackup;
+}
+
+#ifndef SQLITE_OMIT_VACUUM
+/*
+** Unless this is an in-memory or temporary database, clear the pager cache.
+*/
+SQLITE_PRIVATE void sqlite3PagerClearCache(Pager *pPager){
+ assert( MEMDB==0 || pPager->tempFile );
+ if( pPager->tempFile==0 ) pager_reset(pPager);
+}
+#endif
+
+
+#ifndef SQLITE_OMIT_WAL
+/*
+** This function is called when the user invokes "PRAGMA wal_checkpoint",
+** "PRAGMA wal_blocking_checkpoint" or calls the sqlite3_wal_checkpoint()
+** or wal_blocking_checkpoint() API functions.
+**
+** Parameter eMode is one of SQLITE_CHECKPOINT_PASSIVE, FULL or RESTART.
+*/
+SQLITE_PRIVATE int sqlite3PagerCheckpoint(
+ Pager *pPager, /* Checkpoint on this pager */
+ sqlite3 *db, /* Db handle used to check for interrupts */
+ int eMode, /* Type of checkpoint */
+ int *pnLog, /* OUT: Final number of frames in log */
+ int *pnCkpt /* OUT: Final number of checkpointed frames */
+){
+ int rc = SQLITE_OK;
+ if( pPager->pWal ){
+ rc = sqlite3WalCheckpoint(pPager->pWal, db, eMode,
+ (eMode==SQLITE_CHECKPOINT_PASSIVE ? 0 : pPager->xBusyHandler),
+ pPager->pBusyHandlerArg,
+ pPager->walSyncFlags, pPager->pageSize, (u8 *)pPager->pTmpSpace,
+ pnLog, pnCkpt
+ );
+ sqlite3PagerResetLockTimeout(pPager);
+ }
+ return rc;
+}
+
+SQLITE_PRIVATE int sqlite3PagerWalCallback(Pager *pPager){
+ return sqlite3WalCallback(pPager->pWal);
+}
+
+/*
+** Return true if the underlying VFS for the given pager supports the
+** primitives necessary for write-ahead logging.
+*/
+SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager){
+ const sqlite3_io_methods *pMethods = pPager->fd->pMethods;
+ if( pPager->noLock ) return 0;
+ return pPager->exclusiveMode || (pMethods->iVersion>=2 && pMethods->xShmMap);
+}
+
+/*
+** Attempt to take an exclusive lock on the database file. If a PENDING lock
+** is obtained instead, immediately release it.
+*/
+static int pagerExclusiveLock(Pager *pPager){
+ int rc; /* Return code */
+
+ assert( pPager->eLock==SHARED_LOCK || pPager->eLock==EXCLUSIVE_LOCK );
+ rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
+ if( rc!=SQLITE_OK ){
+ /* If the attempt to grab the exclusive lock failed, release the
+ ** pending lock that may have been obtained instead. */
+ pagerUnlockDb(pPager, SHARED_LOCK);
+ }
+
+ return rc;
+}
+
+/*
+** Call sqlite3WalOpen() to open the WAL handle. If the pager is in
+** exclusive-locking mode when this function is called, take an EXCLUSIVE
+** lock on the database file and use heap-memory to store the wal-index
+** in. Otherwise, use the normal shared-memory.
+*/
+static int pagerOpenWal(Pager *pPager){
+ int rc = SQLITE_OK;
+
+ assert( pPager->pWal==0 && pPager->tempFile==0 );
+ assert( pPager->eLock==SHARED_LOCK || pPager->eLock==EXCLUSIVE_LOCK );
+
+ /* If the pager is already in exclusive-mode, the WAL module will use
+ ** heap-memory for the wal-index instead of the VFS shared-memory
+ ** implementation. Take the exclusive lock now, before opening the WAL
+ ** file, to make sure this is safe.
+ */
+ if( pPager->exclusiveMode ){
+ rc = pagerExclusiveLock(pPager);
+ }
+
+ /* Open the connection to the log file. If this operation fails,
+ ** (e.g. due to malloc() failure), return an error code.
+ */
+ if( rc==SQLITE_OK ){
+ rc = sqlite3WalOpen(pPager->pVfs,
+ pPager->fd, pPager->zWal, pPager->exclusiveMode,
+ pPager->journalSizeLimit, &pPager->pWal
+ );
+ }
+ pagerFixMaplimit(pPager);
+
+ return rc;
+}
+
+
+/*
+** The caller must be holding a SHARED lock on the database file to call
+** this function.
+**
+** If the pager passed as the first argument is open on a real database
+** file (not a temp file or an in-memory database), and the WAL file
+** is not already open, make an attempt to open it now. If successful,
+** return SQLITE_OK. If an error occurs or the VFS used by the pager does
+** not support the xShmXXX() methods, return an error code. *pbOpen is
+** not modified in either case.
+**
+** If the pager is open on a temp-file (or in-memory database), or if
+** the WAL file is already open, set *pbOpen to 1 and return SQLITE_OK
+** without doing anything.
+*/
+SQLITE_PRIVATE int sqlite3PagerOpenWal(
+ Pager *pPager, /* Pager object */
+ int *pbOpen /* OUT: Set to true if call is a no-op */
+){
+ int rc = SQLITE_OK; /* Return code */
+
+ assert( assert_pager_state(pPager) );
+ assert( pPager->eState==PAGER_OPEN || pbOpen );
+ assert( pPager->eState==PAGER_READER || !pbOpen );
+ assert( pbOpen==0 || *pbOpen==0 );
+ assert( pbOpen!=0 || (!pPager->tempFile && !pPager->pWal) );
+
+ if( !pPager->tempFile && !pPager->pWal ){
+ if( !sqlite3PagerWalSupported(pPager) ) return SQLITE_CANTOPEN;
+
+ /* Close any rollback journal previously open */
+ sqlite3OsClose(pPager->jfd);
+
+ rc = pagerOpenWal(pPager);
+ if( rc==SQLITE_OK ){
+ pPager->journalMode = PAGER_JOURNALMODE_WAL;
+ pPager->eState = PAGER_OPEN;
+ }
+ }else{
+ *pbOpen = 1;
+ }
+
+ return rc;
+}
+
+/*
+** This function is called to close the connection to the log file prior
+** to switching from WAL to rollback mode.
+**
+** Before closing the log file, this function attempts to take an
+** EXCLUSIVE lock on the database file. If this cannot be obtained, an
+** error (SQLITE_BUSY) is returned and the log connection is not closed.
+** If successful, the EXCLUSIVE lock is not released before returning.
+*/
+SQLITE_PRIVATE int sqlite3PagerCloseWal(Pager *pPager, sqlite3 *db){
+ int rc = SQLITE_OK;
+
+ assert( pPager->journalMode==PAGER_JOURNALMODE_WAL );
+
+ /* If the log file is not already open, but does exist in the file-system,
+ ** it may need to be checkpointed before the connection can switch to
+ ** rollback mode. Open it now so this can happen.
+ */
+ if( !pPager->pWal ){
+ int logexists = 0;
+ rc = pagerLockDb(pPager, SHARED_LOCK);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsAccess(
+ pPager->pVfs, pPager->zWal, SQLITE_ACCESS_EXISTS, &logexists
+ );
+ }
+ if( rc==SQLITE_OK && logexists ){
+ rc = pagerOpenWal(pPager);
+ }
+ }
+
+ /* Checkpoint and close the log. Because an EXCLUSIVE lock is held on
+ ** the database file, the log and log-summary files will be deleted.
+ */
+ if( rc==SQLITE_OK && pPager->pWal ){
+ rc = pagerExclusiveLock(pPager);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3WalClose(pPager->pWal, db, pPager->walSyncFlags,
+ pPager->pageSize, (u8*)pPager->pTmpSpace);
+ pPager->pWal = 0;
+ pagerFixMaplimit(pPager);
+ if( rc && !pPager->exclusiveMode ) pagerUnlockDb(pPager, SHARED_LOCK);
+ }
+ }
+ return rc;
+}
+
+#ifdef SQLITE_ENABLE_SNAPSHOT
+/*
+** If this is a WAL database, obtain a snapshot handle for the snapshot
+** currently open. Otherwise, return an error.
+*/
+SQLITE_PRIVATE int sqlite3PagerSnapshotGet(Pager *pPager, sqlite3_snapshot **ppSnapshot){
+ int rc = SQLITE_ERROR;
+ if( pPager->pWal ){
+ rc = sqlite3WalSnapshotGet(pPager->pWal, ppSnapshot);
+ }
+ return rc;
+}
+
+/*
+** If this is a WAL database, store a pointer to pSnapshot. Next time a
+** read transaction is opened, attempt to read from the snapshot it
+** identifies. If this is not a WAL database, return an error.
+*/
+SQLITE_PRIVATE int sqlite3PagerSnapshotOpen(Pager *pPager, sqlite3_snapshot *pSnapshot){
+ int rc = SQLITE_OK;
+ if( pPager->pWal ){
+ sqlite3WalSnapshotOpen(pPager->pWal, pSnapshot);
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ return rc;
+}
+
+/*
+** If this is a WAL database, call sqlite3WalSnapshotRecover(). If this
+** is not a WAL database, return an error.
+*/
+SQLITE_PRIVATE int sqlite3PagerSnapshotRecover(Pager *pPager){
+ int rc;
+ if( pPager->pWal ){
+ rc = sqlite3WalSnapshotRecover(pPager->pWal);
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ return rc;
+}
+
+/*
+** The caller currently has a read transaction open on the database.
+** If this is not a WAL database, SQLITE_ERROR is returned. Otherwise,
+** this function takes a SHARED lock on the CHECKPOINTER slot and then
+** checks if the snapshot passed as the second argument is still
+** available. If so, SQLITE_OK is returned.
+**
+** If the snapshot is not available, SQLITE_ERROR is returned. Or, if
+** the CHECKPOINTER lock cannot be obtained, SQLITE_BUSY. If any error
+** occurs (any value other than SQLITE_OK is returned), the CHECKPOINTER
+** lock is released before returning.
+*/
+SQLITE_PRIVATE int sqlite3PagerSnapshotCheck(Pager *pPager, sqlite3_snapshot *pSnapshot){
+ int rc;
+ if( pPager->pWal ){
+ rc = sqlite3WalSnapshotCheck(pPager->pWal, pSnapshot);
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ return rc;
+}
+
+/*
+** Release a lock obtained by an earlier successful call to
+** sqlite3PagerSnapshotCheck().
+*/
+SQLITE_PRIVATE void sqlite3PagerSnapshotUnlock(Pager *pPager){
+ assert( pPager->pWal );
+ return sqlite3WalSnapshotUnlock(pPager->pWal);
+}
+
+#endif /* SQLITE_ENABLE_SNAPSHOT */
+#endif /* !SQLITE_OMIT_WAL */
+
+#ifdef SQLITE_ENABLE_ZIPVFS
+/*
+** A read-lock must be held on the pager when this function is called. If
+** the pager is in WAL mode and the WAL file currently contains one or more
+** frames, return the size in bytes of the page images stored within the
+** WAL frames. Otherwise, if this is not a WAL database or the WAL file
+** is empty, return 0.
+*/
+SQLITE_PRIVATE int sqlite3PagerWalFramesize(Pager *pPager){
+ assert( pPager->eState>=PAGER_READER );
+ return sqlite3WalFramesize(pPager->pWal);
+}
+#endif
+
+#endif /* SQLITE_OMIT_DISKIO */
+
+/************** End of pager.c ***********************************************/
+/************** Begin file wal.c *********************************************/
+/*
+** 2010 February 1
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains the implementation of a write-ahead log (WAL) used in
+** "journal_mode=WAL" mode.
+**
+** WRITE-AHEAD LOG (WAL) FILE FORMAT
+**
+** A WAL file consists of a header followed by zero or more "frames".
+** Each frame records the revised content of a single page from the
+** database file. All changes to the database are recorded by writing
+** frames into the WAL. Transactions commit when a frame is written that
+** contains a commit marker. A single WAL can and usually does record
+** multiple transactions. Periodically, the content of the WAL is
+** transferred back into the database file in an operation called a
+** "checkpoint".
+**
+** A single WAL file can be used multiple times. In other words, the
+** WAL can fill up with frames and then be checkpointed and then new
+** frames can overwrite the old ones. A WAL always grows from beginning
+** toward the end. Checksums and counters attached to each frame are
+** used to determine which frames within the WAL are valid and which
+** are leftovers from prior checkpoints.
+**
+** The WAL header is 32 bytes in size and consists of the following eight
+** big-endian 32-bit unsigned integer values:
+**
+** 0: Magic number. 0x377f0682 or 0x377f0683
+** 4: File format version. Currently 3007000
+** 8: Database page size. Example: 1024
+** 12: Checkpoint sequence number
+** 16: Salt-1, random integer incremented with each checkpoint
+** 20: Salt-2, a different random integer changing with each ckpt
+** 24: Checksum-1 (first part of checksum for first 24 bytes of header).
+** 28: Checksum-2 (second part of checksum for first 24 bytes of header).
+**
+** Immediately following the wal-header are zero or more frames. Each
+** frame consists of a 24-byte frame-header followed by a bytes
+** of page data. The frame-header is six big-endian 32-bit unsigned
+** integer values, as follows:
+**
+** 0: Page number.
+** 4: For commit records, the size of the database image in pages
+** after the commit. For all other records, zero.
+** 8: Salt-1 (copied from the header)
+** 12: Salt-2 (copied from the header)
+** 16: Checksum-1.
+** 20: Checksum-2.
+**
+** A frame is considered valid if and only if the following conditions are
+** true:
+**
+** (1) The salt-1 and salt-2 values in the frame-header match
+** salt values in the wal-header
+**
+** (2) The checksum values in the final 8 bytes of the frame-header
+** exactly match the checksum computed consecutively on the
+** WAL header and the first 8 bytes and the content of all frames
+** up to and including the current frame.
+**
+** The checksum is computed using 32-bit big-endian integers if the
+** magic number in the first 4 bytes of the WAL is 0x377f0683 and it
+** is computed using little-endian if the magic number is 0x377f0682.
+** The checksum values are always stored in the frame header in a
+** big-endian format regardless of which byte order is used to compute
+** the checksum. The checksum is computed by interpreting the input as
+** an even number of unsigned 32-bit integers: x[0] through x[N]. The
+** algorithm used for the checksum is as follows:
+**
+** for i from 0 to n-1 step 2:
+** s0 += x[i] + s1;
+** s1 += x[i+1] + s0;
+** endfor
+**
+** Note that s0 and s1 are both weighted checksums using fibonacci weights
+** in reverse order (the largest fibonacci weight occurs on the first element
+** of the sequence being summed.) The s1 value spans all 32-bit
+** terms of the sequence whereas s0 omits the final term.
+**
+** On a checkpoint, the WAL is first VFS.xSync-ed, then valid content of the
+** WAL is transferred into the database, then the database is VFS.xSync-ed.
+** The VFS.xSync operations serve as write barriers - all writes launched
+** before the xSync must complete before any write that launches after the
+** xSync begins.
+**
+** After each checkpoint, the salt-1 value is incremented and the salt-2
+** value is randomized. This prevents old and new frames in the WAL from
+** being considered valid at the same time and being checkpointing together
+** following a crash.
+**
+** READER ALGORITHM
+**
+** To read a page from the database (call it page number P), a reader
+** first checks the WAL to see if it contains page P. If so, then the
+** last valid instance of page P that is a followed by a commit frame
+** or is a commit frame itself becomes the value read. If the WAL
+** contains no copies of page P that are valid and which are a commit
+** frame or are followed by a commit frame, then page P is read from
+** the database file.
+**
+** To start a read transaction, the reader records the index of the last
+** valid frame in the WAL. The reader uses this recorded "mxFrame" value
+** for all subsequent read operations. New transactions can be appended
+** to the WAL, but as long as the reader uses its original mxFrame value
+** and ignores the newly appended content, it will see a consistent snapshot
+** of the database from a single point in time. This technique allows
+** multiple concurrent readers to view different versions of the database
+** content simultaneously.
+**
+** The reader algorithm in the previous paragraphs works correctly, but
+** because frames for page P can appear anywhere within the WAL, the
+** reader has to scan the entire WAL looking for page P frames. If the
+** WAL is large (multiple megabytes is typical) that scan can be slow,
+** and read performance suffers. To overcome this problem, a separate
+** data structure called the wal-index is maintained to expedite the
+** search for frames of a particular page.
+**
+** WAL-INDEX FORMAT
+**
+** Conceptually, the wal-index is shared memory, though VFS implementations
+** might choose to implement the wal-index using a mmapped file. Because
+** the wal-index is shared memory, SQLite does not support journal_mode=WAL
+** on a network filesystem. All users of the database must be able to
+** share memory.
+**
+** In the default unix and windows implementation, the wal-index is a mmapped
+** file whose name is the database name with a "-shm" suffix added. For that
+** reason, the wal-index is sometimes called the "shm" file.
+**
+** The wal-index is transient. After a crash, the wal-index can (and should
+** be) reconstructed from the original WAL file. In fact, the VFS is required
+** to either truncate or zero the header of the wal-index when the last
+** connection to it closes. Because the wal-index is transient, it can
+** use an architecture-specific format; it does not have to be cross-platform.
+** Hence, unlike the database and WAL file formats which store all values
+** as big endian, the wal-index can store multi-byte values in the native
+** byte order of the host computer.
+**
+** The purpose of the wal-index is to answer this question quickly: Given
+** a page number P and a maximum frame index M, return the index of the
+** last frame in the wal before frame M for page P in the WAL, or return
+** NULL if there are no frames for page P in the WAL prior to M.
+**
+** The wal-index consists of a header region, followed by an one or
+** more index blocks.
+**
+** The wal-index header contains the total number of frames within the WAL
+** in the mxFrame field.
+**
+** Each index block except for the first contains information on
+** HASHTABLE_NPAGE frames. The first index block contains information on
+** HASHTABLE_NPAGE_ONE frames. The values of HASHTABLE_NPAGE_ONE and
+** HASHTABLE_NPAGE are selected so that together the wal-index header and
+** first index block are the same size as all other index blocks in the
+** wal-index.
+**
+** Each index block contains two sections, a page-mapping that contains the
+** database page number associated with each wal frame, and a hash-table
+** that allows readers to query an index block for a specific page number.
+** The page-mapping is an array of HASHTABLE_NPAGE (or HASHTABLE_NPAGE_ONE
+** for the first index block) 32-bit page numbers. The first entry in the
+** first index-block contains the database page number corresponding to the
+** first frame in the WAL file. The first entry in the second index block
+** in the WAL file corresponds to the (HASHTABLE_NPAGE_ONE+1)th frame in
+** the log, and so on.
+**
+** The last index block in a wal-index usually contains less than the full
+** complement of HASHTABLE_NPAGE (or HASHTABLE_NPAGE_ONE) page-numbers,
+** depending on the contents of the WAL file. This does not change the
+** allocated size of the page-mapping array - the page-mapping array merely
+** contains unused entries.
+**
+** Even without using the hash table, the last frame for page P
+** can be found by scanning the page-mapping sections of each index block
+** starting with the last index block and moving toward the first, and
+** within each index block, starting at the end and moving toward the
+** beginning. The first entry that equals P corresponds to the frame
+** holding the content for that page.
+**
+** The hash table consists of HASHTABLE_NSLOT 16-bit unsigned integers.
+** HASHTABLE_NSLOT = 2*HASHTABLE_NPAGE, and there is one entry in the
+** hash table for each page number in the mapping section, so the hash
+** table is never more than half full. The expected number of collisions
+** prior to finding a match is 1. Each entry of the hash table is an
+** 1-based index of an entry in the mapping section of the same
+** index block. Let K be the 1-based index of the largest entry in
+** the mapping section. (For index blocks other than the last, K will
+** always be exactly HASHTABLE_NPAGE (4096) and for the last index block
+** K will be (mxFrame%HASHTABLE_NPAGE).) Unused slots of the hash table
+** contain a value of 0.
+**
+** To look for page P in the hash table, first compute a hash iKey on
+** P as follows:
+**
+** iKey = (P * 383) % HASHTABLE_NSLOT
+**
+** Then start scanning entries of the hash table, starting with iKey
+** (wrapping around to the beginning when the end of the hash table is
+** reached) until an unused hash slot is found. Let the first unused slot
+** be at index iUnused. (iUnused might be less than iKey if there was
+** wrap-around.) Because the hash table is never more than half full,
+** the search is guaranteed to eventually hit an unused entry. Let
+** iMax be the value between iKey and iUnused, closest to iUnused,
+** where aHash[iMax]==P. If there is no iMax entry (if there exists
+** no hash slot such that aHash[i]==p) then page P is not in the
+** current index block. Otherwise the iMax-th mapping entry of the
+** current index block corresponds to the last entry that references
+** page P.
+**
+** A hash search begins with the last index block and moves toward the
+** first index block, looking for entries corresponding to page P. On
+** average, only two or three slots in each index block need to be
+** examined in order to either find the last entry for page P, or to
+** establish that no such entry exists in the block. Each index block
+** holds over 4000 entries. So two or three index blocks are sufficient
+** to cover a typical 10 megabyte WAL file, assuming 1K pages. 8 or 10
+** comparisons (on average) suffice to either locate a frame in the
+** WAL or to establish that the frame does not exist in the WAL. This
+** is much faster than scanning the entire 10MB WAL.
+**
+** Note that entries are added in order of increasing K. Hence, one
+** reader might be using some value K0 and a second reader that started
+** at a later time (after additional transactions were added to the WAL
+** and to the wal-index) might be using a different value K1, where K1>K0.
+** Both readers can use the same hash table and mapping section to get
+** the correct result. There may be entries in the hash table with
+** K>K0 but to the first reader, those entries will appear to be unused
+** slots in the hash table and so the first reader will get an answer as
+** if no values greater than K0 had ever been inserted into the hash table
+** in the first place - which is what reader one wants. Meanwhile, the
+** second reader using K1 will see additional values that were inserted
+** later, which is exactly what reader two wants.
+**
+** When a rollback occurs, the value of K is decreased. Hash table entries
+** that correspond to frames greater than the new K value are removed
+** from the hash table at this point.
+*/
+#ifndef SQLITE_OMIT_WAL
+
+/* #include "wal.h" */
+
+/*
+** Trace output macros
+*/
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+SQLITE_PRIVATE int sqlite3WalTrace = 0;
+# define WALTRACE(X) if(sqlite3WalTrace) sqlite3DebugPrintf X
+#else
+# define WALTRACE(X)
+#endif
+
+/*
+** WAL mode depends on atomic aligned 32-bit loads and stores in a few
+** places. The following macros try to make this explicit.
+*/
+#if GCC_VESRION>=5004000
+# define AtomicLoad(PTR) __atomic_load_n((PTR),__ATOMIC_RELAXED)
+# define AtomicStore(PTR,VAL) __atomic_store_n((PTR),(VAL),__ATOMIC_RELAXED)
+#else
+# define AtomicLoad(PTR) (*(PTR))
+# define AtomicStore(PTR,VAL) (*(PTR) = (VAL))
+#endif
+
+/*
+** The maximum (and only) versions of the wal and wal-index formats
+** that may be interpreted by this version of SQLite.
+**
+** If a client begins recovering a WAL file and finds that (a) the checksum
+** values in the wal-header are correct and (b) the version field is not
+** WAL_MAX_VERSION, recovery fails and SQLite returns SQLITE_CANTOPEN.
+**
+** Similarly, if a client successfully reads a wal-index header (i.e. the
+** checksum test is successful) and finds that the version field is not
+** WALINDEX_MAX_VERSION, then no read-transaction is opened and SQLite
+** returns SQLITE_CANTOPEN.
+*/
+#define WAL_MAX_VERSION 3007000
+#define WALINDEX_MAX_VERSION 3007000
+
+/*
+** Index numbers for various locking bytes. WAL_NREADER is the number
+** of available reader locks and should be at least 3. The default
+** is SQLITE_SHM_NLOCK==8 and WAL_NREADER==5.
+**
+** Technically, the various VFSes are free to implement these locks however
+** they see fit. However, compatibility is encouraged so that VFSes can
+** interoperate. The standard implemention used on both unix and windows
+** is for the index number to indicate a byte offset into the
+** WalCkptInfo.aLock[] array in the wal-index header. In other words, all
+** locks are on the shm file. The WALINDEX_LOCK_OFFSET constant (which
+** should be 120) is the location in the shm file for the first locking
+** byte.
+*/
+#define WAL_WRITE_LOCK 0
+#define WAL_ALL_BUT_WRITE 1
+#define WAL_CKPT_LOCK 1
+#define WAL_RECOVER_LOCK 2
+#define WAL_READ_LOCK(I) (3+(I))
+#define WAL_NREADER (SQLITE_SHM_NLOCK-3)
+
+
+/* Object declarations */
+typedef struct WalIndexHdr WalIndexHdr;
+typedef struct WalIterator WalIterator;
+typedef struct WalCkptInfo WalCkptInfo;
+
+
+/*
+** The following object holds a copy of the wal-index header content.
+**
+** The actual header in the wal-index consists of two copies of this
+** object followed by one instance of the WalCkptInfo object.
+** For all versions of SQLite through 3.10.0 and probably beyond,
+** the locking bytes (WalCkptInfo.aLock) start at offset 120 and
+** the total header size is 136 bytes.
+**
+** The szPage value can be any power of 2 between 512 and 32768, inclusive.
+** Or it can be 1 to represent a 65536-byte page. The latter case was
+** added in 3.7.1 when support for 64K pages was added.
+*/
+struct WalIndexHdr {
+ u32 iVersion; /* Wal-index version */
+ u32 unused; /* Unused (padding) field */
+ u32 iChange; /* Counter incremented each transaction */
+ u8 isInit; /* 1 when initialized */
+ u8 bigEndCksum; /* True if checksums in WAL are big-endian */
+ u16 szPage; /* Database page size in bytes. 1==64K */
+ u32 mxFrame; /* Index of last valid frame in the WAL */
+ u32 nPage; /* Size of database in pages */
+ u32 aFrameCksum[2]; /* Checksum of last frame in log */
+ u32 aSalt[2]; /* Two salt values copied from WAL header */
+ u32 aCksum[2]; /* Checksum over all prior fields */
+};
+
+/*
+** A copy of the following object occurs in the wal-index immediately
+** following the second copy of the WalIndexHdr. This object stores
+** information used by checkpoint.
+**
+** nBackfill is the number of frames in the WAL that have been written
+** back into the database. (We call the act of moving content from WAL to
+** database "backfilling".) The nBackfill number is never greater than
+** WalIndexHdr.mxFrame. nBackfill can only be increased by threads
+** holding the WAL_CKPT_LOCK lock (which includes a recovery thread).
+** However, a WAL_WRITE_LOCK thread can move the value of nBackfill from
+** mxFrame back to zero when the WAL is reset.
+**
+** nBackfillAttempted is the largest value of nBackfill that a checkpoint
+** has attempted to achieve. Normally nBackfill==nBackfillAtempted, however
+** the nBackfillAttempted is set before any backfilling is done and the
+** nBackfill is only set after all backfilling completes. So if a checkpoint
+** crashes, nBackfillAttempted might be larger than nBackfill. The
+** WalIndexHdr.mxFrame must never be less than nBackfillAttempted.
+**
+** The aLock[] field is a set of bytes used for locking. These bytes should
+** never be read or written.
+**
+** There is one entry in aReadMark[] for each reader lock. If a reader
+** holds read-lock K, then the value in aReadMark[K] is no greater than
+** the mxFrame for that reader. The value READMARK_NOT_USED (0xffffffff)
+** for any aReadMark[] means that entry is unused. aReadMark[0] is
+** a special case; its value is never used and it exists as a place-holder
+** to avoid having to offset aReadMark[] indexs by one. Readers holding
+** WAL_READ_LOCK(0) always ignore the entire WAL and read all content
+** directly from the database.
+**
+** The value of aReadMark[K] may only be changed by a thread that
+** is holding an exclusive lock on WAL_READ_LOCK(K). Thus, the value of
+** aReadMark[K] cannot changed while there is a reader is using that mark
+** since the reader will be holding a shared lock on WAL_READ_LOCK(K).
+**
+** The checkpointer may only transfer frames from WAL to database where
+** the frame numbers are less than or equal to every aReadMark[] that is
+** in use (that is, every aReadMark[j] for which there is a corresponding
+** WAL_READ_LOCK(j)). New readers (usually) pick the aReadMark[] with the
+** largest value and will increase an unused aReadMark[] to mxFrame if there
+** is not already an aReadMark[] equal to mxFrame. The exception to the
+** previous sentence is when nBackfill equals mxFrame (meaning that everything
+** in the WAL has been backfilled into the database) then new readers
+** will choose aReadMark[0] which has value 0 and hence such reader will
+** get all their all content directly from the database file and ignore
+** the WAL.
+**
+** Writers normally append new frames to the end of the WAL. However,
+** if nBackfill equals mxFrame (meaning that all WAL content has been
+** written back into the database) and if no readers are using the WAL
+** (in other words, if there are no WAL_READ_LOCK(i) where i>0) then
+** the writer will first "reset" the WAL back to the beginning and start
+** writing new content beginning at frame 1.
+**
+** We assume that 32-bit loads are atomic and so no locks are needed in
+** order to read from any aReadMark[] entries.
+*/
+struct WalCkptInfo {
+ u32 nBackfill; /* Number of WAL frames backfilled into DB */
+ u32 aReadMark[WAL_NREADER]; /* Reader marks */
+ u8 aLock[SQLITE_SHM_NLOCK]; /* Reserved space for locks */
+ u32 nBackfillAttempted; /* WAL frames perhaps written, or maybe not */
+ u32 notUsed0; /* Available for future enhancements */
+};
+#define READMARK_NOT_USED 0xffffffff
+
+
+/* A block of WALINDEX_LOCK_RESERVED bytes beginning at
+** WALINDEX_LOCK_OFFSET is reserved for locks. Since some systems
+** only support mandatory file-locks, we do not read or write data
+** from the region of the file on which locks are applied.
+*/
+#define WALINDEX_LOCK_OFFSET (sizeof(WalIndexHdr)*2+offsetof(WalCkptInfo,aLock))
+#define WALINDEX_HDR_SIZE (sizeof(WalIndexHdr)*2+sizeof(WalCkptInfo))
+
+/* Size of header before each frame in wal */
+#define WAL_FRAME_HDRSIZE 24
+
+/* Size of write ahead log header, including checksum. */
+#define WAL_HDRSIZE 32
+
+/* WAL magic value. Either this value, or the same value with the least
+** significant bit also set (WAL_MAGIC | 0x00000001) is stored in 32-bit
+** big-endian format in the first 4 bytes of a WAL file.
+**
+** If the LSB is set, then the checksums for each frame within the WAL
+** file are calculated by treating all data as an array of 32-bit
+** big-endian words. Otherwise, they are calculated by interpreting
+** all data as 32-bit little-endian words.
+*/
+#define WAL_MAGIC 0x377f0682
+
+/*
+** Return the offset of frame iFrame in the write-ahead log file,
+** assuming a database page size of szPage bytes. The offset returned
+** is to the start of the write-ahead log frame-header.
+*/
+#define walFrameOffset(iFrame, szPage) ( \
+ WAL_HDRSIZE + ((iFrame)-1)*(i64)((szPage)+WAL_FRAME_HDRSIZE) \
+)
+
+/*
+** An open write-ahead log file is represented by an instance of the
+** following object.
+*/
+struct Wal {
+ sqlite3_vfs *pVfs; /* The VFS used to create pDbFd */
+ sqlite3_file *pDbFd; /* File handle for the database file */
+ sqlite3_file *pWalFd; /* File handle for WAL file */
+ u32 iCallback; /* Value to pass to log callback (or 0) */
+ i64 mxWalSize; /* Truncate WAL to this size upon reset */
+ int nWiData; /* Size of array apWiData */
+ int szFirstBlock; /* Size of first block written to WAL file */
+ volatile u32 **apWiData; /* Pointer to wal-index content in memory */
+ u32 szPage; /* Database page size */
+ i16 readLock; /* Which read lock is being held. -1 for none */
+ u8 syncFlags; /* Flags to use to sync header writes */
+ u8 exclusiveMode; /* Non-zero if connection is in exclusive mode */
+ u8 writeLock; /* True if in a write transaction */
+ u8 ckptLock; /* True if holding a checkpoint lock */
+ u8 readOnly; /* WAL_RDWR, WAL_RDONLY, or WAL_SHM_RDONLY */
+ u8 truncateOnCommit; /* True to truncate WAL file on commit */
+ u8 syncHeader; /* Fsync the WAL header if true */
+ u8 padToSectorBoundary; /* Pad transactions out to the next sector */
+ u8 bShmUnreliable; /* SHM content is read-only and unreliable */
+ WalIndexHdr hdr; /* Wal-index header for current transaction */
+ u32 minFrame; /* Ignore wal frames before this one */
+ u32 iReCksum; /* On commit, recalculate checksums from here */
+ const char *zWalName; /* Name of WAL file */
+ u32 nCkpt; /* Checkpoint sequence counter in the wal-header */
+#ifdef SQLITE_DEBUG
+ u8 lockError; /* True if a locking error has occurred */
+#endif
+#ifdef SQLITE_ENABLE_SNAPSHOT
+ WalIndexHdr *pSnapshot; /* Start transaction here if not NULL */
+#endif
+};
+
+/*
+** Candidate values for Wal.exclusiveMode.
+*/
+#define WAL_NORMAL_MODE 0
+#define WAL_EXCLUSIVE_MODE 1
+#define WAL_HEAPMEMORY_MODE 2
+
+/*
+** Possible values for WAL.readOnly
+*/
+#define WAL_RDWR 0 /* Normal read/write connection */
+#define WAL_RDONLY 1 /* The WAL file is readonly */
+#define WAL_SHM_RDONLY 2 /* The SHM file is readonly */
+
+/*
+** Each page of the wal-index mapping contains a hash-table made up of
+** an array of HASHTABLE_NSLOT elements of the following type.
+*/
+typedef u16 ht_slot;
+
+/*
+** This structure is used to implement an iterator that loops through
+** all frames in the WAL in database page order. Where two or more frames
+** correspond to the same database page, the iterator visits only the
+** frame most recently written to the WAL (in other words, the frame with
+** the largest index).
+**
+** The internals of this structure are only accessed by:
+**
+** walIteratorInit() - Create a new iterator,
+** walIteratorNext() - Step an iterator,
+** walIteratorFree() - Free an iterator.
+**
+** This functionality is used by the checkpoint code (see walCheckpoint()).
+*/
+struct WalIterator {
+ int iPrior; /* Last result returned from the iterator */
+ int nSegment; /* Number of entries in aSegment[] */
+ struct WalSegment {
+ int iNext; /* Next slot in aIndex[] not yet returned */
+ ht_slot *aIndex; /* i0, i1, i2... such that aPgno[iN] ascend */
+ u32 *aPgno; /* Array of page numbers. */
+ int nEntry; /* Nr. of entries in aPgno[] and aIndex[] */
+ int iZero; /* Frame number associated with aPgno[0] */
+ } aSegment[1]; /* One for every 32KB page in the wal-index */
+};
+
+/*
+** Define the parameters of the hash tables in the wal-index file. There
+** is a hash-table following every HASHTABLE_NPAGE page numbers in the
+** wal-index.
+**
+** Changing any of these constants will alter the wal-index format and
+** create incompatibilities.
+*/
+#define HASHTABLE_NPAGE 4096 /* Must be power of 2 */
+#define HASHTABLE_HASH_1 383 /* Should be prime */
+#define HASHTABLE_NSLOT (HASHTABLE_NPAGE*2) /* Must be a power of 2 */
+
+/*
+** The block of page numbers associated with the first hash-table in a
+** wal-index is smaller than usual. This is so that there is a complete
+** hash-table on each aligned 32KB page of the wal-index.
+*/
+#define HASHTABLE_NPAGE_ONE (HASHTABLE_NPAGE - (WALINDEX_HDR_SIZE/sizeof(u32)))
+
+/* The wal-index is divided into pages of WALINDEX_PGSZ bytes each. */
+#define WALINDEX_PGSZ ( \
+ sizeof(ht_slot)*HASHTABLE_NSLOT + HASHTABLE_NPAGE*sizeof(u32) \
+)
+
+/*
+** Obtain a pointer to the iPage'th page of the wal-index. The wal-index
+** is broken into pages of WALINDEX_PGSZ bytes. Wal-index pages are
+** numbered from zero.
+**
+** If the wal-index is currently smaller the iPage pages then the size
+** of the wal-index might be increased, but only if it is safe to do
+** so. It is safe to enlarge the wal-index if pWal->writeLock is true
+** or pWal->exclusiveMode==WAL_HEAPMEMORY_MODE.
+**
+** If this call is successful, *ppPage is set to point to the wal-index
+** page and SQLITE_OK is returned. If an error (an OOM or VFS error) occurs,
+** then an SQLite error code is returned and *ppPage is set to 0.
+*/
+static SQLITE_NOINLINE int walIndexPageRealloc(
+ Wal *pWal, /* The WAL context */
+ int iPage, /* The page we seek */
+ volatile u32 **ppPage /* Write the page pointer here */
+){
+ int rc = SQLITE_OK;
+
+ /* Enlarge the pWal->apWiData[] array if required */
+ if( pWal->nWiData<=iPage ){
+ int nByte = sizeof(u32*)*(iPage+1);
+ volatile u32 **apNew;
+ apNew = (volatile u32 **)sqlite3_realloc64((void *)pWal->apWiData, nByte);
+ if( !apNew ){
+ *ppPage = 0;
+ return SQLITE_NOMEM_BKPT;
+ }
+ memset((void*)&apNew[pWal->nWiData], 0,
+ sizeof(u32*)*(iPage+1-pWal->nWiData));
+ pWal->apWiData = apNew;
+ pWal->nWiData = iPage+1;
+ }
+
+ /* Request a pointer to the required page from the VFS */
+ assert( pWal->apWiData[iPage]==0 );
+ if( pWal->exclusiveMode==WAL_HEAPMEMORY_MODE ){
+ pWal->apWiData[iPage] = (u32 volatile *)sqlite3MallocZero(WALINDEX_PGSZ);
+ if( !pWal->apWiData[iPage] ) rc = SQLITE_NOMEM_BKPT;
+ }else{
+ rc = sqlite3OsShmMap(pWal->pDbFd, iPage, WALINDEX_PGSZ,
+ pWal->writeLock, (void volatile **)&pWal->apWiData[iPage]
+ );
+ assert( pWal->apWiData[iPage]!=0 || rc!=SQLITE_OK || pWal->writeLock==0 );
+ testcase( pWal->apWiData[iPage]==0 && rc==SQLITE_OK );
+ if( (rc&0xff)==SQLITE_READONLY ){
+ pWal->readOnly |= WAL_SHM_RDONLY;
+ if( rc==SQLITE_READONLY ){
+ rc = SQLITE_OK;
+ }
+ }
+ }
+
+ *ppPage = pWal->apWiData[iPage];
+ assert( iPage==0 || *ppPage || rc!=SQLITE_OK );
+ return rc;
+}
+static int walIndexPage(
+ Wal *pWal, /* The WAL context */
+ int iPage, /* The page we seek */
+ volatile u32 **ppPage /* Write the page pointer here */
+){
+ if( pWal->nWiData<=iPage || (*ppPage = pWal->apWiData[iPage])==0 ){
+ return walIndexPageRealloc(pWal, iPage, ppPage);
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Return a pointer to the WalCkptInfo structure in the wal-index.
+*/
+static volatile WalCkptInfo *walCkptInfo(Wal *pWal){
+ assert( pWal->nWiData>0 && pWal->apWiData[0] );
+ return (volatile WalCkptInfo*)&(pWal->apWiData[0][sizeof(WalIndexHdr)/2]);
+}
+
+/*
+** Return a pointer to the WalIndexHdr structure in the wal-index.
+*/
+static volatile WalIndexHdr *walIndexHdr(Wal *pWal){
+ assert( pWal->nWiData>0 && pWal->apWiData[0] );
+ return (volatile WalIndexHdr*)pWal->apWiData[0];
+}
+
+/*
+** The argument to this macro must be of type u32. On a little-endian
+** architecture, it returns the u32 value that results from interpreting
+** the 4 bytes as a big-endian value. On a big-endian architecture, it
+** returns the value that would be produced by interpreting the 4 bytes
+** of the input value as a little-endian integer.
+*/
+#define BYTESWAP32(x) ( \
+ (((x)&0x000000FF)<<24) + (((x)&0x0000FF00)<<8) \
+ + (((x)&0x00FF0000)>>8) + (((x)&0xFF000000)>>24) \
+)
+
+/*
+** Generate or extend an 8 byte checksum based on the data in
+** array aByte[] and the initial values of aIn[0] and aIn[1] (or
+** initial values of 0 and 0 if aIn==NULL).
+**
+** The checksum is written back into aOut[] before returning.
+**
+** nByte must be a positive multiple of 8.
+*/
+static void walChecksumBytes(
+ int nativeCksum, /* True for native byte-order, false for non-native */
+ u8 *a, /* Content to be checksummed */
+ int nByte, /* Bytes of content in a[]. Must be a multiple of 8. */
+ const u32 *aIn, /* Initial checksum value input */
+ u32 *aOut /* OUT: Final checksum value output */
+){
+ u32 s1, s2;
+ u32 *aData = (u32 *)a;
+ u32 *aEnd = (u32 *)&a[nByte];
+
+ if( aIn ){
+ s1 = aIn[0];
+ s2 = aIn[1];
+ }else{
+ s1 = s2 = 0;
+ }
+
+ assert( nByte>=8 );
+ assert( (nByte&0x00000007)==0 );
+
+ if( nativeCksum ){
+ do {
+ s1 += *aData++ + s2;
+ s2 += *aData++ + s1;
+ }while( aDataexclusiveMode!=WAL_HEAPMEMORY_MODE ){
+ sqlite3OsShmBarrier(pWal->pDbFd);
+ }
+}
+
+/*
+** Write the header information in pWal->hdr into the wal-index.
+**
+** The checksum on pWal->hdr is updated before it is written.
+*/
+static void walIndexWriteHdr(Wal *pWal){
+ volatile WalIndexHdr *aHdr = walIndexHdr(pWal);
+ const int nCksum = offsetof(WalIndexHdr, aCksum);
+
+ assert( pWal->writeLock );
+ pWal->hdr.isInit = 1;
+ pWal->hdr.iVersion = WALINDEX_MAX_VERSION;
+ walChecksumBytes(1, (u8*)&pWal->hdr, nCksum, 0, pWal->hdr.aCksum);
+ memcpy((void*)&aHdr[1], (const void*)&pWal->hdr, sizeof(WalIndexHdr));
+ walShmBarrier(pWal);
+ memcpy((void*)&aHdr[0], (const void*)&pWal->hdr, sizeof(WalIndexHdr));
+}
+
+/*
+** This function encodes a single frame header and writes it to a buffer
+** supplied by the caller. A frame-header is made up of a series of
+** 4-byte big-endian integers, as follows:
+**
+** 0: Page number.
+** 4: For commit records, the size of the database image in pages
+** after the commit. For all other records, zero.
+** 8: Salt-1 (copied from the wal-header)
+** 12: Salt-2 (copied from the wal-header)
+** 16: Checksum-1.
+** 20: Checksum-2.
+*/
+static void walEncodeFrame(
+ Wal *pWal, /* The write-ahead log */
+ u32 iPage, /* Database page number for frame */
+ u32 nTruncate, /* New db size (or 0 for non-commit frames) */
+ u8 *aData, /* Pointer to page data */
+ u8 *aFrame /* OUT: Write encoded frame here */
+){
+ int nativeCksum; /* True for native byte-order checksums */
+ u32 *aCksum = pWal->hdr.aFrameCksum;
+ assert( WAL_FRAME_HDRSIZE==24 );
+ sqlite3Put4byte(&aFrame[0], iPage);
+ sqlite3Put4byte(&aFrame[4], nTruncate);
+ if( pWal->iReCksum==0 ){
+ memcpy(&aFrame[8], pWal->hdr.aSalt, 8);
+
+ nativeCksum = (pWal->hdr.bigEndCksum==SQLITE_BIGENDIAN);
+ walChecksumBytes(nativeCksum, aFrame, 8, aCksum, aCksum);
+ walChecksumBytes(nativeCksum, aData, pWal->szPage, aCksum, aCksum);
+
+ sqlite3Put4byte(&aFrame[16], aCksum[0]);
+ sqlite3Put4byte(&aFrame[20], aCksum[1]);
+ }else{
+ memset(&aFrame[8], 0, 16);
+ }
+}
+
+/*
+** Check to see if the frame with header in aFrame[] and content
+** in aData[] is valid. If it is a valid frame, fill *piPage and
+** *pnTruncate and return true. Return if the frame is not valid.
+*/
+static int walDecodeFrame(
+ Wal *pWal, /* The write-ahead log */
+ u32 *piPage, /* OUT: Database page number for frame */
+ u32 *pnTruncate, /* OUT: New db size (or 0 if not commit) */
+ u8 *aData, /* Pointer to page data (for checksum) */
+ u8 *aFrame /* Frame data */
+){
+ int nativeCksum; /* True for native byte-order checksums */
+ u32 *aCksum = pWal->hdr.aFrameCksum;
+ u32 pgno; /* Page number of the frame */
+ assert( WAL_FRAME_HDRSIZE==24 );
+
+ /* A frame is only valid if the salt values in the frame-header
+ ** match the salt values in the wal-header.
+ */
+ if( memcmp(&pWal->hdr.aSalt, &aFrame[8], 8)!=0 ){
+ return 0;
+ }
+
+ /* A frame is only valid if the page number is creater than zero.
+ */
+ pgno = sqlite3Get4byte(&aFrame[0]);
+ if( pgno==0 ){
+ return 0;
+ }
+
+ /* A frame is only valid if a checksum of the WAL header,
+ ** all prior frams, the first 16 bytes of this frame-header,
+ ** and the frame-data matches the checksum in the last 8
+ ** bytes of this frame-header.
+ */
+ nativeCksum = (pWal->hdr.bigEndCksum==SQLITE_BIGENDIAN);
+ walChecksumBytes(nativeCksum, aFrame, 8, aCksum, aCksum);
+ walChecksumBytes(nativeCksum, aData, pWal->szPage, aCksum, aCksum);
+ if( aCksum[0]!=sqlite3Get4byte(&aFrame[16])
+ || aCksum[1]!=sqlite3Get4byte(&aFrame[20])
+ ){
+ /* Checksum failed. */
+ return 0;
+ }
+
+ /* If we reach this point, the frame is valid. Return the page number
+ ** and the new database size.
+ */
+ *piPage = pgno;
+ *pnTruncate = sqlite3Get4byte(&aFrame[4]);
+ return 1;
+}
+
+
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+/*
+** Names of locks. This routine is used to provide debugging output and is not
+** a part of an ordinary build.
+*/
+static const char *walLockName(int lockIdx){
+ if( lockIdx==WAL_WRITE_LOCK ){
+ return "WRITE-LOCK";
+ }else if( lockIdx==WAL_CKPT_LOCK ){
+ return "CKPT-LOCK";
+ }else if( lockIdx==WAL_RECOVER_LOCK ){
+ return "RECOVER-LOCK";
+ }else{
+ static char zName[15];
+ sqlite3_snprintf(sizeof(zName), zName, "READ-LOCK[%d]",
+ lockIdx-WAL_READ_LOCK(0));
+ return zName;
+ }
+}
+#endif /*defined(SQLITE_TEST) || defined(SQLITE_DEBUG) */
+
+
+/*
+** Set or release locks on the WAL. Locks are either shared or exclusive.
+** A lock cannot be moved directly between shared and exclusive - it must go
+** through the unlocked state first.
+**
+** In locking_mode=EXCLUSIVE, all of these routines become no-ops.
+*/
+static int walLockShared(Wal *pWal, int lockIdx){
+ int rc;
+ if( pWal->exclusiveMode ) return SQLITE_OK;
+ rc = sqlite3OsShmLock(pWal->pDbFd, lockIdx, 1,
+ SQLITE_SHM_LOCK | SQLITE_SHM_SHARED);
+ WALTRACE(("WAL%p: acquire SHARED-%s %s\n", pWal,
+ walLockName(lockIdx), rc ? "failed" : "ok"));
+ VVA_ONLY( pWal->lockError = (u8)(rc!=SQLITE_OK && rc!=SQLITE_BUSY); )
+ return rc;
+}
+static void walUnlockShared(Wal *pWal, int lockIdx){
+ if( pWal->exclusiveMode ) return;
+ (void)sqlite3OsShmLock(pWal->pDbFd, lockIdx, 1,
+ SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED);
+ WALTRACE(("WAL%p: release SHARED-%s\n", pWal, walLockName(lockIdx)));
+}
+static int walLockExclusive(Wal *pWal, int lockIdx, int n){
+ int rc;
+ if( pWal->exclusiveMode ) return SQLITE_OK;
+ rc = sqlite3OsShmLock(pWal->pDbFd, lockIdx, n,
+ SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE);
+ WALTRACE(("WAL%p: acquire EXCLUSIVE-%s cnt=%d %s\n", pWal,
+ walLockName(lockIdx), n, rc ? "failed" : "ok"));
+ VVA_ONLY( pWal->lockError = (u8)(rc!=SQLITE_OK && rc!=SQLITE_BUSY); )
+ return rc;
+}
+static void walUnlockExclusive(Wal *pWal, int lockIdx, int n){
+ if( pWal->exclusiveMode ) return;
+ (void)sqlite3OsShmLock(pWal->pDbFd, lockIdx, n,
+ SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE);
+ WALTRACE(("WAL%p: release EXCLUSIVE-%s cnt=%d\n", pWal,
+ walLockName(lockIdx), n));
+}
+
+/*
+** Compute a hash on a page number. The resulting hash value must land
+** between 0 and (HASHTABLE_NSLOT-1). The walHashNext() function advances
+** the hash to the next value in the event of a collision.
+*/
+static int walHash(u32 iPage){
+ assert( iPage>0 );
+ assert( (HASHTABLE_NSLOT & (HASHTABLE_NSLOT-1))==0 );
+ return (iPage*HASHTABLE_HASH_1) & (HASHTABLE_NSLOT-1);
+}
+static int walNextHash(int iPriorHash){
+ return (iPriorHash+1)&(HASHTABLE_NSLOT-1);
+}
+
+/*
+** An instance of the WalHashLoc object is used to describe the location
+** of a page hash table in the wal-index. This becomes the return value
+** from walHashGet().
+*/
+typedef struct WalHashLoc WalHashLoc;
+struct WalHashLoc {
+ volatile ht_slot *aHash; /* Start of the wal-index hash table */
+ volatile u32 *aPgno; /* aPgno[1] is the page of first frame indexed */
+ u32 iZero; /* One less than the frame number of first indexed*/
+};
+
+/*
+** Return pointers to the hash table and page number array stored on
+** page iHash of the wal-index. The wal-index is broken into 32KB pages
+** numbered starting from 0.
+**
+** Set output variable pLoc->aHash to point to the start of the hash table
+** in the wal-index file. Set pLoc->iZero to one less than the frame
+** number of the first frame indexed by this hash table. If a
+** slot in the hash table is set to N, it refers to frame number
+** (pLoc->iZero+N) in the log.
+**
+** Finally, set pLoc->aPgno so that pLoc->aPgno[1] is the page number of the
+** first frame indexed by the hash table, frame (pLoc->iZero+1).
+*/
+static int walHashGet(
+ Wal *pWal, /* WAL handle */
+ int iHash, /* Find the iHash'th table */
+ WalHashLoc *pLoc /* OUT: Hash table location */
+){
+ int rc; /* Return code */
+
+ rc = walIndexPage(pWal, iHash, &pLoc->aPgno);
+ assert( rc==SQLITE_OK || iHash>0 );
+
+ if( rc==SQLITE_OK ){
+ pLoc->aHash = (volatile ht_slot *)&pLoc->aPgno[HASHTABLE_NPAGE];
+ if( iHash==0 ){
+ pLoc->aPgno = &pLoc->aPgno[WALINDEX_HDR_SIZE/sizeof(u32)];
+ pLoc->iZero = 0;
+ }else{
+ pLoc->iZero = HASHTABLE_NPAGE_ONE + (iHash-1)*HASHTABLE_NPAGE;
+ }
+ pLoc->aPgno = &pLoc->aPgno[-1];
+ }
+ return rc;
+}
+
+/*
+** Return the number of the wal-index page that contains the hash-table
+** and page-number array that contain entries corresponding to WAL frame
+** iFrame. The wal-index is broken up into 32KB pages. Wal-index pages
+** are numbered starting from 0.
+*/
+static int walFramePage(u32 iFrame){
+ int iHash = (iFrame+HASHTABLE_NPAGE-HASHTABLE_NPAGE_ONE-1) / HASHTABLE_NPAGE;
+ assert( (iHash==0 || iFrame>HASHTABLE_NPAGE_ONE)
+ && (iHash>=1 || iFrame<=HASHTABLE_NPAGE_ONE)
+ && (iHash<=1 || iFrame>(HASHTABLE_NPAGE_ONE+HASHTABLE_NPAGE))
+ && (iHash>=2 || iFrame<=HASHTABLE_NPAGE_ONE+HASHTABLE_NPAGE)
+ && (iHash<=2 || iFrame>(HASHTABLE_NPAGE_ONE+2*HASHTABLE_NPAGE))
+ );
+ return iHash;
+}
+
+/*
+** Return the page number associated with frame iFrame in this WAL.
+*/
+static u32 walFramePgno(Wal *pWal, u32 iFrame){
+ int iHash = walFramePage(iFrame);
+ if( iHash==0 ){
+ return pWal->apWiData[0][WALINDEX_HDR_SIZE/sizeof(u32) + iFrame - 1];
+ }
+ return pWal->apWiData[iHash][(iFrame-1-HASHTABLE_NPAGE_ONE)%HASHTABLE_NPAGE];
+}
+
+/*
+** Remove entries from the hash table that point to WAL slots greater
+** than pWal->hdr.mxFrame.
+**
+** This function is called whenever pWal->hdr.mxFrame is decreased due
+** to a rollback or savepoint.
+**
+** At most only the hash table containing pWal->hdr.mxFrame needs to be
+** updated. Any later hash tables will be automatically cleared when
+** pWal->hdr.mxFrame advances to the point where those hash tables are
+** actually needed.
+*/
+static void walCleanupHash(Wal *pWal){
+ WalHashLoc sLoc; /* Hash table location */
+ int iLimit = 0; /* Zero values greater than this */
+ int nByte; /* Number of bytes to zero in aPgno[] */
+ int i; /* Used to iterate through aHash[] */
+
+ assert( pWal->writeLock );
+ testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE-1 );
+ testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE );
+ testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE+1 );
+
+ if( pWal->hdr.mxFrame==0 ) return;
+
+ /* Obtain pointers to the hash-table and page-number array containing
+ ** the entry that corresponds to frame pWal->hdr.mxFrame. It is guaranteed
+ ** that the page said hash-table and array reside on is already mapped.
+ */
+ assert( pWal->nWiData>walFramePage(pWal->hdr.mxFrame) );
+ assert( pWal->apWiData[walFramePage(pWal->hdr.mxFrame)] );
+ walHashGet(pWal, walFramePage(pWal->hdr.mxFrame), &sLoc);
+
+ /* Zero all hash-table entries that correspond to frame numbers greater
+ ** than pWal->hdr.mxFrame.
+ */
+ iLimit = pWal->hdr.mxFrame - sLoc.iZero;
+ assert( iLimit>0 );
+ for(i=0; iiLimit ){
+ sLoc.aHash[i] = 0;
+ }
+ }
+
+ /* Zero the entries in the aPgno array that correspond to frames with
+ ** frame numbers greater than pWal->hdr.mxFrame.
+ */
+ nByte = (int)((char *)sLoc.aHash - (char *)&sLoc.aPgno[iLimit+1]);
+ memset((void *)&sLoc.aPgno[iLimit+1], 0, nByte);
+
+#ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT
+ /* Verify that the every entry in the mapping region is still reachable
+ ** via the hash table even after the cleanup.
+ */
+ if( iLimit ){
+ int j; /* Loop counter */
+ int iKey; /* Hash key */
+ for(j=1; j<=iLimit; j++){
+ for(iKey=walHash(sLoc.aPgno[j]);sLoc.aHash[iKey];iKey=walNextHash(iKey)){
+ if( sLoc.aHash[iKey]==j ) break;
+ }
+ assert( sLoc.aHash[iKey]==j );
+ }
+ }
+#endif /* SQLITE_ENABLE_EXPENSIVE_ASSERT */
+}
+
+
+/*
+** Set an entry in the wal-index that will map database page number
+** pPage into WAL frame iFrame.
+*/
+static int walIndexAppend(Wal *pWal, u32 iFrame, u32 iPage){
+ int rc; /* Return code */
+ WalHashLoc sLoc; /* Wal-index hash table location */
+
+ rc = walHashGet(pWal, walFramePage(iFrame), &sLoc);
+
+ /* Assuming the wal-index file was successfully mapped, populate the
+ ** page number array and hash table entry.
+ */
+ if( rc==SQLITE_OK ){
+ int iKey; /* Hash table key */
+ int idx; /* Value to write to hash-table slot */
+ int nCollide; /* Number of hash collisions */
+
+ idx = iFrame - sLoc.iZero;
+ assert( idx <= HASHTABLE_NSLOT/2 + 1 );
+
+ /* If this is the first entry to be added to this hash-table, zero the
+ ** entire hash table and aPgno[] array before proceeding.
+ */
+ if( idx==1 ){
+ int nByte = (int)((u8 *)&sLoc.aHash[HASHTABLE_NSLOT]
+ - (u8 *)&sLoc.aPgno[1]);
+ memset((void*)&sLoc.aPgno[1], 0, nByte);
+ }
+
+ /* If the entry in aPgno[] is already set, then the previous writer
+ ** must have exited unexpectedly in the middle of a transaction (after
+ ** writing one or more dirty pages to the WAL to free up memory).
+ ** Remove the remnants of that writers uncommitted transaction from
+ ** the hash-table before writing any new entries.
+ */
+ if( sLoc.aPgno[idx] ){
+ walCleanupHash(pWal);
+ assert( !sLoc.aPgno[idx] );
+ }
+
+ /* Write the aPgno[] array entry and the hash-table slot. */
+ nCollide = idx;
+ for(iKey=walHash(iPage); sLoc.aHash[iKey]; iKey=walNextHash(iKey)){
+ if( (nCollide--)==0 ) return SQLITE_CORRUPT_BKPT;
+ }
+ sLoc.aPgno[idx] = iPage;
+ sLoc.aHash[iKey] = (ht_slot)idx;
+
+#ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT
+ /* Verify that the number of entries in the hash table exactly equals
+ ** the number of entries in the mapping region.
+ */
+ {
+ int i; /* Loop counter */
+ int nEntry = 0; /* Number of entries in the hash table */
+ for(i=0; ickptLock==1 || pWal->ckptLock==0 );
+ assert( WAL_ALL_BUT_WRITE==WAL_WRITE_LOCK+1 );
+ assert( WAL_CKPT_LOCK==WAL_ALL_BUT_WRITE );
+ assert( pWal->writeLock );
+ iLock = WAL_ALL_BUT_WRITE + pWal->ckptLock;
+ rc = walLockExclusive(pWal, iLock, WAL_READ_LOCK(0)-iLock);
+ if( rc==SQLITE_OK ){
+ rc = walLockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1);
+ if( rc!=SQLITE_OK ){
+ walUnlockExclusive(pWal, iLock, WAL_READ_LOCK(0)-iLock);
+ }
+ }
+ if( rc ){
+ return rc;
+ }
+
+ WALTRACE(("WAL%p: recovery begin...\n", pWal));
+
+ memset(&pWal->hdr, 0, sizeof(WalIndexHdr));
+
+ rc = sqlite3OsFileSize(pWal->pWalFd, &nSize);
+ if( rc!=SQLITE_OK ){
+ goto recovery_error;
+ }
+
+ if( nSize>WAL_HDRSIZE ){
+ u8 aBuf[WAL_HDRSIZE]; /* Buffer to load WAL header into */
+ u8 *aFrame = 0; /* Malloc'd buffer to load entire frame */
+ int szFrame; /* Number of bytes in buffer aFrame[] */
+ u8 *aData; /* Pointer to data part of aFrame buffer */
+ int iFrame; /* Index of last frame read */
+ i64 iOffset; /* Next offset to read from log file */
+ int szPage; /* Page size according to the log */
+ u32 magic; /* Magic value read from WAL header */
+ u32 version; /* Magic value read from WAL header */
+ int isValid; /* True if this frame is valid */
+
+ /* Read in the WAL header. */
+ rc = sqlite3OsRead(pWal->pWalFd, aBuf, WAL_HDRSIZE, 0);
+ if( rc!=SQLITE_OK ){
+ goto recovery_error;
+ }
+
+ /* If the database page size is not a power of two, or is greater than
+ ** SQLITE_MAX_PAGE_SIZE, conclude that the WAL file contains no valid
+ ** data. Similarly, if the 'magic' value is invalid, ignore the whole
+ ** WAL file.
+ */
+ magic = sqlite3Get4byte(&aBuf[0]);
+ szPage = sqlite3Get4byte(&aBuf[8]);
+ if( (magic&0xFFFFFFFE)!=WAL_MAGIC
+ || szPage&(szPage-1)
+ || szPage>SQLITE_MAX_PAGE_SIZE
+ || szPage<512
+ ){
+ goto finished;
+ }
+ pWal->hdr.bigEndCksum = (u8)(magic&0x00000001);
+ pWal->szPage = szPage;
+ pWal->nCkpt = sqlite3Get4byte(&aBuf[12]);
+ memcpy(&pWal->hdr.aSalt, &aBuf[16], 8);
+
+ /* Verify that the WAL header checksum is correct */
+ walChecksumBytes(pWal->hdr.bigEndCksum==SQLITE_BIGENDIAN,
+ aBuf, WAL_HDRSIZE-2*4, 0, pWal->hdr.aFrameCksum
+ );
+ if( pWal->hdr.aFrameCksum[0]!=sqlite3Get4byte(&aBuf[24])
+ || pWal->hdr.aFrameCksum[1]!=sqlite3Get4byte(&aBuf[28])
+ ){
+ goto finished;
+ }
+
+ /* Verify that the version number on the WAL format is one that
+ ** are able to understand */
+ version = sqlite3Get4byte(&aBuf[4]);
+ if( version!=WAL_MAX_VERSION ){
+ rc = SQLITE_CANTOPEN_BKPT;
+ goto finished;
+ }
+
+ /* Malloc a buffer to read frames into. */
+ szFrame = szPage + WAL_FRAME_HDRSIZE;
+ aFrame = (u8 *)sqlite3_malloc64(szFrame);
+ if( !aFrame ){
+ rc = SQLITE_NOMEM_BKPT;
+ goto recovery_error;
+ }
+ aData = &aFrame[WAL_FRAME_HDRSIZE];
+
+ /* Read all frames from the log file. */
+ iFrame = 0;
+ for(iOffset=WAL_HDRSIZE; (iOffset+szFrame)<=nSize; iOffset+=szFrame){
+ u32 pgno; /* Database page number for frame */
+ u32 nTruncate; /* dbsize field from frame header */
+
+ /* Read and decode the next log frame. */
+ iFrame++;
+ rc = sqlite3OsRead(pWal->pWalFd, aFrame, szFrame, iOffset);
+ if( rc!=SQLITE_OK ) break;
+ isValid = walDecodeFrame(pWal, &pgno, &nTruncate, aData, aFrame);
+ if( !isValid ) break;
+ rc = walIndexAppend(pWal, iFrame, pgno);
+ if( rc!=SQLITE_OK ) break;
+
+ /* If nTruncate is non-zero, this is a commit record. */
+ if( nTruncate ){
+ pWal->hdr.mxFrame = iFrame;
+ pWal->hdr.nPage = nTruncate;
+ pWal->hdr.szPage = (u16)((szPage&0xff00) | (szPage>>16));
+ testcase( szPage<=32768 );
+ testcase( szPage>=65536 );
+ aFrameCksum[0] = pWal->hdr.aFrameCksum[0];
+ aFrameCksum[1] = pWal->hdr.aFrameCksum[1];
+ }
+ }
+
+ sqlite3_free(aFrame);
+ }
+
+finished:
+ if( rc==SQLITE_OK ){
+ volatile WalCkptInfo *pInfo;
+ int i;
+ pWal->hdr.aFrameCksum[0] = aFrameCksum[0];
+ pWal->hdr.aFrameCksum[1] = aFrameCksum[1];
+ walIndexWriteHdr(pWal);
+
+ /* Reset the checkpoint-header. This is safe because this thread is
+ ** currently holding locks that exclude all other readers, writers and
+ ** checkpointers.
+ */
+ pInfo = walCkptInfo(pWal);
+ pInfo->nBackfill = 0;
+ pInfo->nBackfillAttempted = pWal->hdr.mxFrame;
+ pInfo->aReadMark[0] = 0;
+ for(i=1; iaReadMark[i] = READMARK_NOT_USED;
+ if( pWal->hdr.mxFrame ) pInfo->aReadMark[1] = pWal->hdr.mxFrame;
+
+ /* If more than one frame was recovered from the log file, report an
+ ** event via sqlite3_log(). This is to help with identifying performance
+ ** problems caused by applications routinely shutting down without
+ ** checkpointing the log file.
+ */
+ if( pWal->hdr.nPage ){
+ sqlite3_log(SQLITE_NOTICE_RECOVER_WAL,
+ "recovered %d frames from WAL file %s",
+ pWal->hdr.mxFrame, pWal->zWalName
+ );
+ }
+ }
+
+recovery_error:
+ WALTRACE(("WAL%p: recovery %s\n", pWal, rc ? "failed" : "ok"));
+ walUnlockExclusive(pWal, iLock, WAL_READ_LOCK(0)-iLock);
+ walUnlockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1);
+ return rc;
+}
+
+/*
+** Close an open wal-index.
+*/
+static void walIndexClose(Wal *pWal, int isDelete){
+ if( pWal->exclusiveMode==WAL_HEAPMEMORY_MODE || pWal->bShmUnreliable ){
+ int i;
+ for(i=0; inWiData; i++){
+ sqlite3_free((void *)pWal->apWiData[i]);
+ pWal->apWiData[i] = 0;
+ }
+ }
+ if( pWal->exclusiveMode!=WAL_HEAPMEMORY_MODE ){
+ sqlite3OsShmUnmap(pWal->pDbFd, isDelete);
+ }
+}
+
+/*
+** Open a connection to the WAL file zWalName. The database file must
+** already be opened on connection pDbFd. The buffer that zWalName points
+** to must remain valid for the lifetime of the returned Wal* handle.
+**
+** A SHARED lock should be held on the database file when this function
+** is called. The purpose of this SHARED lock is to prevent any other
+** client from unlinking the WAL or wal-index file. If another process
+** were to do this just after this client opened one of these files, the
+** system would be badly broken.
+**
+** If the log file is successfully opened, SQLITE_OK is returned and
+** *ppWal is set to point to a new WAL handle. If an error occurs,
+** an SQLite error code is returned and *ppWal is left unmodified.
+*/
+SQLITE_PRIVATE int sqlite3WalOpen(
+ sqlite3_vfs *pVfs, /* vfs module to open wal and wal-index */
+ sqlite3_file *pDbFd, /* The open database file */
+ const char *zWalName, /* Name of the WAL file */
+ int bNoShm, /* True to run in heap-memory mode */
+ i64 mxWalSize, /* Truncate WAL to this size on reset */
+ Wal **ppWal /* OUT: Allocated Wal handle */
+){
+ int rc; /* Return Code */
+ Wal *pRet; /* Object to allocate and return */
+ int flags; /* Flags passed to OsOpen() */
+
+ assert( zWalName && zWalName[0] );
+ assert( pDbFd );
+
+ /* In the amalgamation, the os_unix.c and os_win.c source files come before
+ ** this source file. Verify that the #defines of the locking byte offsets
+ ** in os_unix.c and os_win.c agree with the WALINDEX_LOCK_OFFSET value.
+ ** For that matter, if the lock offset ever changes from its initial design
+ ** value of 120, we need to know that so there is an assert() to check it.
+ */
+ assert( 120==WALINDEX_LOCK_OFFSET );
+ assert( 136==WALINDEX_HDR_SIZE );
+#ifdef WIN_SHM_BASE
+ assert( WIN_SHM_BASE==WALINDEX_LOCK_OFFSET );
+#endif
+#ifdef UNIX_SHM_BASE
+ assert( UNIX_SHM_BASE==WALINDEX_LOCK_OFFSET );
+#endif
+
+
+ /* Allocate an instance of struct Wal to return. */
+ *ppWal = 0;
+ pRet = (Wal*)sqlite3MallocZero(sizeof(Wal) + pVfs->szOsFile);
+ if( !pRet ){
+ return SQLITE_NOMEM_BKPT;
+ }
+
+ pRet->pVfs = pVfs;
+ pRet->pWalFd = (sqlite3_file *)&pRet[1];
+ pRet->pDbFd = pDbFd;
+ pRet->readLock = -1;
+ pRet->mxWalSize = mxWalSize;
+ pRet->zWalName = zWalName;
+ pRet->syncHeader = 1;
+ pRet->padToSectorBoundary = 1;
+ pRet->exclusiveMode = (bNoShm ? WAL_HEAPMEMORY_MODE: WAL_NORMAL_MODE);
+
+ /* Open file handle on the write-ahead log file. */
+ flags = (SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|SQLITE_OPEN_WAL);
+ rc = sqlite3OsOpen(pVfs, zWalName, pRet->pWalFd, flags, &flags);
+ if( rc==SQLITE_OK && flags&SQLITE_OPEN_READONLY ){
+ pRet->readOnly = WAL_RDONLY;
+ }
+
+ if( rc!=SQLITE_OK ){
+ walIndexClose(pRet, 0);
+ sqlite3OsClose(pRet->pWalFd);
+ sqlite3_free(pRet);
+ }else{
+ int iDC = sqlite3OsDeviceCharacteristics(pDbFd);
+ if( iDC & SQLITE_IOCAP_SEQUENTIAL ){ pRet->syncHeader = 0; }
+ if( iDC & SQLITE_IOCAP_POWERSAFE_OVERWRITE ){
+ pRet->padToSectorBoundary = 0;
+ }
+ *ppWal = pRet;
+ WALTRACE(("WAL%d: opened\n", pRet));
+ }
+ return rc;
+}
+
+/*
+** Change the size to which the WAL file is trucated on each reset.
+*/
+SQLITE_PRIVATE void sqlite3WalLimit(Wal *pWal, i64 iLimit){
+ if( pWal ) pWal->mxWalSize = iLimit;
+}
+
+/*
+** Find the smallest page number out of all pages held in the WAL that
+** has not been returned by any prior invocation of this method on the
+** same WalIterator object. Write into *piFrame the frame index where
+** that page was last written into the WAL. Write into *piPage the page
+** number.
+**
+** Return 0 on success. If there are no pages in the WAL with a page
+** number larger than *piPage, then return 1.
+*/
+static int walIteratorNext(
+ WalIterator *p, /* Iterator */
+ u32 *piPage, /* OUT: The page number of the next page */
+ u32 *piFrame /* OUT: Wal frame index of next page */
+){
+ u32 iMin; /* Result pgno must be greater than iMin */
+ u32 iRet = 0xFFFFFFFF; /* 0xffffffff is never a valid page number */
+ int i; /* For looping through segments */
+
+ iMin = p->iPrior;
+ assert( iMin<0xffffffff );
+ for(i=p->nSegment-1; i>=0; i--){
+ struct WalSegment *pSegment = &p->aSegment[i];
+ while( pSegment->iNextnEntry ){
+ u32 iPg = pSegment->aPgno[pSegment->aIndex[pSegment->iNext]];
+ if( iPg>iMin ){
+ if( iPgiZero + pSegment->aIndex[pSegment->iNext];
+ }
+ break;
+ }
+ pSegment->iNext++;
+ }
+ }
+
+ *piPage = p->iPrior = iRet;
+ return (iRet==0xFFFFFFFF);
+}
+
+/*
+** This function merges two sorted lists into a single sorted list.
+**
+** aLeft[] and aRight[] are arrays of indices. The sort key is
+** aContent[aLeft[]] and aContent[aRight[]]. Upon entry, the following
+** is guaranteed for all J0 && nRight>0 );
+ while( iRight=nRight || aContent[aLeft[iLeft]]=nLeft || aContent[aLeft[iLeft]]>dbpage );
+ assert( iRight>=nRight || aContent[aRight[iRight]]>dbpage );
+ }
+
+ *paRight = aLeft;
+ *pnRight = iOut;
+ memcpy(aLeft, aTmp, sizeof(aTmp[0])*iOut);
+}
+
+/*
+** Sort the elements in list aList using aContent[] as the sort key.
+** Remove elements with duplicate keys, preferring to keep the
+** larger aList[] values.
+**
+** The aList[] entries are indices into aContent[]. The values in
+** aList[] are to be sorted so that for all J0 );
+ assert( HASHTABLE_NPAGE==(1<<(ArraySize(aSub)-1)) );
+
+ for(iList=0; iListaList && p->nList<=(1<aList==&aList[iList&~((2<aList, p->nList, &aMerge, &nMerge, aBuffer);
+ }
+ aSub[iSub].aList = aMerge;
+ aSub[iSub].nList = nMerge;
+ }
+
+ for(iSub++; iSub