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warzone2100/lib/sqlite3/sqlite3.h

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/*
** 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 library
** presents to client programs. If a C-function, structure, datatype,
** or constant definition does not appear in this file, then it is
** not a published API of SQLite, is subject to change without
** notice, and should not be referenced by programs that use SQLite.
**
** Some of the definitions that are in this file are marked as
** "experimental". Experimental interfaces are normally new
** features recently added to SQLite. We do not anticipate changes
** to experimental interfaces but reserve to make minor changes if
** experience from use "in the wild" suggest such changes are prudent.
**
** The official C-language API documentation for SQLite is derived
** from comments in this file. This file is the authoritative source
** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.421 2008/12/30 06:24:58 danielk1977 Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h> /* Needed for the definition of va_list */
/*
** Make sure we can call this stuff from C++.
*/
#ifdef __cplusplus
extern "C" {
#endif
/*
** Add the ability to override 'extern'
*/
#ifndef SQLITE_EXTERN
# define SQLITE_EXTERN extern
#endif
/*
** These no-op macros are used in front of interfaces to mark those
** interfaces as either deprecated or experimental. New applications
** should not use deprecated intrfaces - they are support for backwards
** compatibility only. Application writers should be aware that
** experimental interfaces are subject to change in point releases.
**
** These macros used to resolve to various kinds of compiler magic that
** would generate warning messages when they were used. But that
** compiler magic ended up generating such a flurry of bug reports
** that we have taken it all out and gone back to using simple
** noop macros.
*/
#define SQLITE_DEPRECATED
#define SQLITE_EXPERIMENTAL
/*
** Ensure these symbols were not defined by some previous header file.
*/
#ifdef SQLITE_VERSION
# undef SQLITE_VERSION
#endif
#ifdef SQLITE_VERSION_NUMBER
# undef SQLITE_VERSION_NUMBER
#endif
/*
** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100>
**
** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in
** the sqlite3.h file specify the version of SQLite with which
** that header file is associated.
**
** The "version" of SQLite is a string of the form "X.Y.Z".
** The phrase "alpha" or "beta" might be appended after the Z.
** The X value is major version number always 3 in SQLite3.
** The X value only changes when backwards compatibility is
** broken and we intend to never break backwards compatibility.
** The Y value is the minor version number and only changes when
** there are major feature enhancements that are forwards compatible
** but not backwards compatible.
** The Z value is the release number and is incremented with
** each release but resets back to 0 whenever Y is incremented.
**
** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()].
**
** INVARIANTS:
**
** {H10011} The SQLITE_VERSION #define in the sqlite3.h header file shall
** evaluate to a string literal that is the SQLite version
** with which the header file is associated.
**
** {H10014} The SQLITE_VERSION_NUMBER #define shall resolve to an integer
** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z
** are the major version, minor version, and release number.
*/
#define SQLITE_VERSION "3.6.10"
#define SQLITE_VERSION_NUMBER 3006010
/*
** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
** KEYWORDS: sqlite3_version
**
** These features provide the same information as the [SQLITE_VERSION]
** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated
** with the library instead of the header file. Cautious programmers might
** include a check in their application to verify that
** sqlite3_libversion_number() always returns the value
** [SQLITE_VERSION_NUMBER].
**
** The sqlite3_libversion() function returns the same information as is
** in the sqlite3_version[] string constant. The function is provided
** for use in DLLs since DLL users usually do not have direct access to string
** constants within the DLL.
**
** INVARIANTS:
**
** {H10021} The [sqlite3_libversion_number()] interface shall return
** an integer equal to [SQLITE_VERSION_NUMBER].
**
** {H10022} The [sqlite3_version] string constant shall contain
** the text of the [SQLITE_VERSION] string.
**
** {H10023} The [sqlite3_libversion()] function shall return
** a pointer to the [sqlite3_version] string constant.
*/
SQLITE_EXTERN const char sqlite3_version[];
const char *sqlite3_libversion(void);
int sqlite3_libversion_number(void);
/*
** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100>
**
** SQLite can be compiled with or without mutexes. When
** the [SQLITE_THREADSAFE] C preprocessor macro 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 a program 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 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_MUTEX]. The return value of this function shows
** only the default compile-time setting, not any run-time changes
** to that setting.
**
** See the [threading mode] documentation for additional information.
**
** INVARIANTS:
**
** {H10101} The [sqlite3_threadsafe()] function shall return zero if
** and only if SQLite was compiled with mutexing code omitted.
**
** {H10102} The value returned by the [sqlite3_threadsafe()] function
** shall remain the same across calls to [sqlite3_config()].
*/
int sqlite3_threadsafe(void);
/*
** CAPI3REF: Database Connection Handle {H12000} <S40200>
** 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()]
** is its destructor. 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 {H10200} <S10110>
** 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.
**
** INVARIANTS:
**
** {H10201} The [sqlite_int64] and [sqlite3_int64] type shall specify
** a 64-bit signed integer.
**
** {H10202} The [sqlite_uint64] and [sqlite3_uint64] type shall specify
** a 64-bit unsigned integer.
*/
#ifdef SQLITE_INT64_TYPE
typedef SQLITE_INT64_TYPE sqlite_int64;
typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
#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 {H12010} <S30100><S40200>
**
** This routine is the destructor for the [sqlite3] object.
**
** Applications should [sqlite3_finalize | finalize] all [prepared statements]
** and [sqlite3_blob_close | close] all [BLOB handles] associated with
** the [sqlite3] object prior to attempting to close the object.
** The [sqlite3_next_stmt()] interface can be used to locate all
** [prepared statements] associated with a [database connection] if desired.
** Typical code might look like this:
**
** <blockquote><pre>
** sqlite3_stmt *pStmt;
** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){
** &nbsp; sqlite3_finalize(pStmt);
** }
** </pre></blockquote>
**
** If [sqlite3_close()] is invoked while a transaction is open,
** the transaction is automatically rolled back.
**
** INVARIANTS:
**
** {H12011} A successful call to [sqlite3_close(C)] shall destroy the
** [database connection] object C.
**
** {H12012} A successful call to [sqlite3_close(C)] shall return SQLITE_OK.
**
** {H12013} A successful call to [sqlite3_close(C)] shall release all
** memory and system resources associated with [database connection]
** C.
**
** {H12014} A call to [sqlite3_close(C)] on a [database connection] C that
** has one or more open [prepared statements] shall fail with
** an [SQLITE_BUSY] error code.
**
** {H12015} A call to [sqlite3_close(C)] where C is a NULL pointer shall
** be a harmless no-op returning SQLITE_OK.
**
** {H12019} When [sqlite3_close(C)] is invoked on a [database connection] C
** that has a pending transaction, the transaction shall be
** rolled back.
**
** ASSUMPTIONS:
**
** {A12016} The C parameter to [sqlite3_close(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.
*/
int sqlite3_close(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 {H12100} <S10000>
**
** The sqlite3_exec() interface is a convenient way of running one or more
** SQL statements without having to write a lot of C code. The UTF-8 encoded
** SQL statements are passed in as the second parameter to sqlite3_exec().
** The statements are evaluated one by one until either an error or
** an interrupt is encountered, or until they are all done. The 3rd parameter
** is an optional callback that is invoked once for each row of any query
** results produced by the SQL statements. The 5th parameter tells where
** to write any error messages.
**
** The error message passed back through the 5th parameter is held
** in memory obtained from [sqlite3_malloc()]. To avoid a memory leak,
** the calling application should call [sqlite3_free()] on any error
** message returned through the 5th parameter when it has finished using
** the error message.
**
** If the SQL statement in the 2nd parameter is NULL or an empty string
** or a string containing only whitespace and comments, then no SQL
** statements are evaluated and the database is not changed.
**
** The sqlite3_exec() interface is implemented in terms of
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
** The sqlite3_exec() routine does nothing to the database that cannot be done
** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
**
** INVARIANTS:
**
** {H12101} A successful invocation of [sqlite3_exec(D,S,C,A,E)]
** shall sequentially evaluate all of the UTF-8 encoded,
** semicolon-separated SQL statements in the zero-terminated
** string S within the context of the [database connection] D.
**
** {H12102} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL then
** the actions of the interface shall be the same as if the
** S parameter were an empty string.
**
** {H12104} The return value of [sqlite3_exec()] shall be [SQLITE_OK] if all
** SQL statements run successfully and to completion.
**
** {H12105} The return value of [sqlite3_exec()] shall be an appropriate
** non-zero [error code] if any SQL statement fails.
**
** {H12107} If one or more of the SQL statements handed to [sqlite3_exec()]
** return results and the 3rd parameter is not NULL, then
** the callback function specified by the 3rd parameter shall be
** invoked once for each row of result.
**
** {H12110} If the callback returns a non-zero value then [sqlite3_exec()]
** shall abort the SQL statement it is currently evaluating,
** skip all subsequent SQL statements, and return [SQLITE_ABORT].
**
** {H12113} The [sqlite3_exec()] routine shall pass its 4th parameter through
** as the 1st parameter of the callback.
**
** {H12116} The [sqlite3_exec()] routine shall set the 2nd parameter of its
** callback to be the number of columns in the current row of
** result.
**
** {H12119} The [sqlite3_exec()] routine shall set the 3rd parameter of its
** callback to be an array of pointers to strings holding the
** values for each column in the current result set row as
** obtained from [sqlite3_column_text()].
**
** {H12122} The [sqlite3_exec()] routine shall set the 4th parameter of its
** callback to be an array of pointers to strings holding the
** names of result columns as obtained from [sqlite3_column_name()].
**
** {H12125} If the 3rd parameter to [sqlite3_exec()] is NULL then
** [sqlite3_exec()] shall silently discard query results.
**
** {H12131} If an error occurs while parsing or evaluating any of the SQL
** statements in the S parameter of [sqlite3_exec(D,S,C,A,E)] and if
** the E parameter is not NULL, then [sqlite3_exec()] shall store
** in *E an appropriate error message written into memory obtained
** from [sqlite3_malloc()].
**
** {H12134} The [sqlite3_exec(D,S,C,A,E)] routine shall set the value of
** *E to NULL if E is not NULL and there are no errors.
**
** {H12137} The [sqlite3_exec(D,S,C,A,E)] function shall set the [error code]
** and message accessible via [sqlite3_errcode()],
** [sqlite3_extended_errcode()],
** [sqlite3_errmsg()], and [sqlite3_errmsg16()].
**
** {H12138} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL or an
** empty string or contains nothing other than whitespace, comments,
** and/or semicolons, then results of [sqlite3_errcode()],
** [sqlite3_extended_errcode()],
** [sqlite3_errmsg()], and [sqlite3_errmsg16()]
** shall reset to indicate no errors.
**
** ASSUMPTIONS:
**
** {A12141} The first parameter to [sqlite3_exec()] must be an valid and open
** [database connection].
**
** {A12142} The database connection must not be closed while
** [sqlite3_exec()] is running.
**
** {A12143} The calling function should use [sqlite3_free()] to free
** the memory that *errmsg is left pointing at once the error
** message is no longer needed.
**
** {A12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()]
** must remain unchanged while [sqlite3_exec()] is running.
*/
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 {H10210} <S10700>
** KEYWORDS: SQLITE_OK {error code} {error codes}
** KEYWORDS: {result code} {result codes}
**
** Many SQLite functions return an integer result code from the set shown
** here in order to indicates success or failure.
**
** New error codes may be added in future versions of SQLite.
**
** See also: [SQLITE_IOERR_READ | extended result codes]
*/
#define SQLITE_OK 0 /* Successful result */
/* beginning-of-error-codes */
#define SQLITE_ERROR 1 /* SQL error or missing database */
#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 /* NOT USED. Table or record not found */
#define SQLITE_FULL 13 /* Insertion failed because database is full */
#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
#define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */
#define SQLITE_EMPTY 16 /* Database is empty */
#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 /* Auxiliary database format error */
#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_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 {H10220} <S10700>
** KEYWORDS: {extended error code} {extended error codes}
** KEYWORDS: {extended result code} {extended result codes}
**
** In its default configuration, SQLite API routines return one of 26 integer
** [SQLITE_OK | 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 and later) include
** support for additional result codes that provide more detailed information
** about errors. The extended result codes are enabled or disabled
** on a per database connection basis using the
** [sqlite3_extended_result_codes()] API.
**
** Some of the available extended result codes are listed here.
** One may expect the number of extended result codes will be expand
** over time. Software that uses extended result codes should expect
** to see new result codes in future releases of SQLite.
**
** The SQLITE_OK result code will never be extended. It will always
** be exactly zero.
**
** INVARIANTS:
**
** {H10223} The symbolic name for an extended result code shall contains
** a related primary result code as a prefix.
**
** {H10224} Primary result code names shall contain a single "_" character.
**
** {H10225} Extended result code names shall contain two or more "_" characters.
**
** {H10226} The numeric value of an extended result code shall contain the
** numeric value of its corresponding primary result code in
** its least significant 8 bits.
*/
#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))
/*
** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700>
**
** These bit values are intended for use in the
** 3rd parameter to the [sqlite3_open_v2()] interface and
** in the 4th parameter to the xOpen method of the
** [sqlite3_vfs] object.
*/
#define SQLITE_OPEN_READONLY 0x00000001
#define SQLITE_OPEN_READWRITE 0x00000002
#define SQLITE_OPEN_CREATE 0x00000004
#define SQLITE_OPEN_DELETEONCLOSE 0x00000008
#define SQLITE_OPEN_EXCLUSIVE 0x00000010
#define SQLITE_OPEN_MAIN_DB 0x00000100
#define SQLITE_OPEN_TEMP_DB 0x00000200
#define SQLITE_OPEN_TRANSIENT_DB 0x00000400
#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800
#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000
#define SQLITE_OPEN_SUBJOURNAL 0x00002000
#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000
#define SQLITE_OPEN_NOMUTEX 0x00008000
#define SQLITE_OPEN_FULLMUTEX 0x00010000
/*
** CAPI3REF: Device Characteristics {H10240} <H11120>
**
** The xDeviceCapabilities method of the [sqlite3_io_methods]
** object returns an integer which is a vector of the 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().
*/
#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
/*
** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310>
**
** 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 {H10260} <H11120>
**
** 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. The SQLITE_SYNC_NORMAL flag means
** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means
** to use Mac OS X style fullsync instead of fsync().
*/
#define SQLITE_SYNC_NORMAL 0x00002
#define SQLITE_SYNC_FULL 0x00003
#define SQLITE_SYNC_DATAONLY 0x00010
/*
** CAPI3REF: OS Interface Open File Handle {H11110} <S20110>
**
** An [sqlite3_file] object represents an open file in the 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 {H11120} <S20110>
**
** 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.
**
** 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
** <ul>
** <li> [SQLITE_LOCK_NONE],
** <li> [SQLITE_LOCK_SHARED],
** <li> [SQLITE_LOCK_RESERVED],
** <li> [SQLITE_LOCK_PENDING], or
** <li> [SQLITE_LOCK_EXCLUSIVE].
** </ul>
** 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 [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
** Applications that define a custom xFileControl method should use opcodes
** greater than 100 to avoid conflicts.
**
** 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:
**
** <ul>
** <li> [SQLITE_IOCAP_ATOMIC]
** <li> [SQLITE_IOCAP_ATOMIC512]
** <li> [SQLITE_IOCAP_ATOMIC1K]
** <li> [SQLITE_IOCAP_ATOMIC2K]
** <li> [SQLITE_IOCAP_ATOMIC4K]
** <li> [SQLITE_IOCAP_ATOMIC8K]
** <li> [SQLITE_IOCAP_ATOMIC16K]
** <li> [SQLITE_IOCAP_ATOMIC32K]
** <li> [SQLITE_IOCAP_ATOMIC64K]
** <li> [SQLITE_IOCAP_SAFE_APPEND]
** <li> [SQLITE_IOCAP_SEQUENTIAL]
** </ul>
**
** 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*);
/* Additional methods may be added in future releases */
};
/*
** CAPI3REF: Standard File Control Opcodes {H11310} <S30800>
**
** These integer constants are opcodes for the xFileControl method
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
** interface.
**
** 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 only needs to be supported when SQLITE_TEST
** is defined.
*/
#define SQLITE_FCNTL_LOCKSTATE 1
#define SQLITE_GET_LOCKPROXYFILE 2
#define SQLITE_SET_LOCKPROXYFILE 3
#define SQLITE_LAST_ERRNO 4
/*
** CAPI3REF: Mutex Handle {H17110} <S20130>
**
** 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: OS Interface Object {H11140} <S20100>
**
** 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".
**
** The value of the iVersion field is initially 1 but may be larger in
** future versions of SQLite. Additional fields may be appended to this
** object when the iVersion value is increased. Note that the structure
** of the sqlite3_vfs object changes in the transaction between
** SQLite version 3.5.9 and 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.
**
** SQLite will guarantee that the zFilename parameter to xOpen
** is either a NULL pointer or string obtained
** from xFullPathname(). SQLite further guarantees that
** the string will be valid and unchanged until xClose() is
** called. Because of the previous sentense,
** 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 is xOpen is a NULL pointer then xOpen
** must invite 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:
**
** <ul>
** <li> [SQLITE_OPEN_MAIN_DB]
** <li> [SQLITE_OPEN_MAIN_JOURNAL]
** <li> [SQLITE_OPEN_TEMP_DB]
** <li> [SQLITE_OPEN_TEMP_JOURNAL]
** <li> [SQLITE_OPEN_TRANSIENT_DB]
** <li> [SQLITE_OPEN_SUBJOURNAL]
** <li> [SQLITE_OPEN_MASTER_JOURNAL]
** </ul>
**
** 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:
**
** <ul>
** <li> [SQLITE_OPEN_DELETEONCLOSE]
** <li> [SQLITE_OPEN_EXCLUSIVE]
** </ul>
**
** 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, journals and for subjournals.
**
** The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened
** for exclusive access. This flag is set for all files except
** for the main database file.
**
** 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.
**
** 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(), and xCurrentTime() 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.
**
*/
typedef struct sqlite3_vfs sqlite3_vfs;
struct sqlite3_vfs {
int iVersion; /* Structure version number */
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 *);
/* New fields may be appended in figure versions. The iVersion
** value will increment whenever this happens. */
};
/*
** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140>
**
** These integer constants can be used as the third parameter to
** the xAccess method of an [sqlite3_vfs] object. {END} 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 file is both readable and writable.
** With SQLITE_ACCESS_READ, the xAccess method
** checks whether the file is readable.
*/
#define SQLITE_ACCESS_EXISTS 0
#define SQLITE_ACCESS_READWRITE 1
#define SQLITE_ACCESS_READ 2
/*
** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100>
**
** The sqlite3_initialize() routine initializes the
** SQLite library. The sqlite3_shutdown() routine
** deallocates any resources that were allocated by sqlite3_initialize().
**
** 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.
**
** Among other things, sqlite3_initialize() shall invoke
** sqlite3_os_init(). Similarly, sqlite3_shutdown()
** shall 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 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.
*/
int sqlite3_initialize(void);
int sqlite3_shutdown(void);
int sqlite3_os_init(void);
int sqlite3_os_end(void);
/*
** CAPI3REF: Configuring The SQLite Library {H14100} <S20000><S30200>
** EXPERIMENTAL
**
** 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 insure that no other SQLite interfaces are invoked by other
** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
** may only be invoked prior to library initialization using
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
** 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
** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
** what property of SQLite is to be configured. Subsequent arguments
** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | 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].
**
** INVARIANTS:
**
** {H14103} A successful invocation of [sqlite3_config()] shall return
** [SQLITE_OK].
**
** {H14106} The [sqlite3_config()] interface shall return [SQLITE_MISUSE]
** if it is invoked in between calls to [sqlite3_initialize()] and
** [sqlite3_shutdown()].
**
** {H14120} A successful call to [sqlite3_config]([SQLITE_CONFIG_SINGLETHREAD])
** shall set the default [threading mode] to Single-thread.
**
** {H14123} A successful call to [sqlite3_config]([SQLITE_CONFIG_MULTITHREAD])
** shall set the default [threading mode] to Multi-thread.
**
** {H14126} A successful call to [sqlite3_config]([SQLITE_CONFIG_SERIALIZED])
** shall set the default [threading mode] to Serialized.
**
** {H14129} A successful call to [sqlite3_config]([SQLITE_CONFIG_MUTEX],X)
** where X is a pointer to an initialized [sqlite3_mutex_methods]
** object shall cause all subsequent mutex operations performed
** by SQLite to use the mutex methods that were present in X
** during the call to [sqlite3_config()].
**
** {H14132} A successful call to [sqlite3_config]([SQLITE_CONFIG_GETMUTEX],X)
** where X is a pointer to an [sqlite3_mutex_methods] object
** shall overwrite the content of [sqlite3_mutex_methods] object
** with the mutex methods currently in use by SQLite.
**
** {H14135} A successful call to [sqlite3_config]([SQLITE_CONFIG_MALLOC],M)
** where M is a pointer to an initialized [sqlite3_mem_methods]
** object shall cause all subsequent memory allocation operations
** performed by SQLite to use the methods that were present in
** M during the call to [sqlite3_config()].
**
** {H14138} A successful call to [sqlite3_config]([SQLITE_CONFIG_GETMALLOC],M)
** where M is a pointer to an [sqlite3_mem_methods] object shall
** overwrite the content of [sqlite3_mem_methods] object with
** the memory allocation methods currently in use by
** SQLite.
**
** {H14141} A successful call to [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],1)
** shall enable the memory allocation status collection logic.
**
** {H14144} A successful call to [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],0)
** shall disable the memory allocation status collection logic.
**
** {H14147} The memory allocation status collection logic shall be
** enabled by default.
**
** {H14150} A successful call to [sqlite3_config]([SQLITE_CONFIG_SCRATCH],S,Z,N)
** where Z and N are non-negative integers and
** S is a pointer to an aligned memory buffer not less than
** Z*N bytes in size shall cause S to be used by the
** [scratch memory allocator] for as many as N simulataneous
** allocations each of size (Z & ~7).
**
** {H14153} A successful call to [sqlite3_config]([SQLITE_CONFIG_SCRATCH],S,Z,N)
** where S is a NULL pointer shall disable the
** [scratch memory allocator].
**
** {H14156} A successful call to
** [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],S,Z,N)
** where Z and N are non-negative integers and
** S is a pointer to an aligned memory buffer not less than
** Z*N bytes in size shall cause S to be used by the
** [pagecache memory allocator] for as many as N simulataneous
** allocations each of size (Z & ~7).
**
** {H14159} A successful call to
** [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],S,Z,N)
** where S is a NULL pointer shall disable the
** [pagecache memory allocator].
**
** {H14162} A successful call to [sqlite3_config]([SQLITE_CONFIG_HEAP],H,Z,N)
** where Z and N are non-negative integers and
** H is a pointer to an aligned memory buffer not less than
** Z bytes in size shall enable the [memsys5] memory allocator
** and cause it to use buffer S as its memory source and to use
** a minimum allocation size of N.
**
** {H14165} A successful call to [sqlite3_config]([SQLITE_CONFIG_HEAP],H,Z,N)
** where H is a NULL pointer shall disable the
** [memsys5] memory allocator.
**
** {H14168} A successful call to [sqlite3_config]([SQLITE_CONFIG_LOOKASIDE],Z,N)
** shall cause the default [lookaside memory allocator] configuration
** for new [database connections] to be N slots of Z bytes each.
*/
SQLITE_EXPERIMENTAL int sqlite3_config(int, ...);
/*
** CAPI3REF: Configure database connections {H14200} <S20000>
** EXPERIMENTAL
**
** 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
** sqlite3_db_config() interface can only be used immediately after
** the database connection is created using [sqlite3_open()],
** [sqlite3_open16()], or [sqlite3_open_v2()].
**
** The second argument to sqlite3_db_config(D,V,...) is the
** configuration verb - an integer code that indicates what
** aspect of the [database connection] is being configured.
** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
** New verbs are likely to be added in future releases of SQLite.
** Additional arguments depend on the verb.
**
** INVARIANTS:
**
** {H14203} A call to [sqlite3_db_config(D,V,...)] shall return [SQLITE_OK]
** if and only if the call is successful.
**
** {H14206} If one or more slots of the [lookaside memory allocator] for
** [database connection] D are in use, then a call to
** [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],...) shall
** fail with an [SQLITE_BUSY] return code.
**
** {H14209} A successful call to
** [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where
** D is an open [database connection] and Z and N are positive
** integers and B is an aligned buffer at least Z*N bytes in size
** shall cause the [lookaside memory allocator] for D to use buffer B
** with N slots of Z bytes each.
**
** {H14212} A successful call to
** [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where
** D is an open [database connection] and Z and N are positive
** integers and B is NULL pointer shall cause the
** [lookaside memory allocator] for D to a obtain Z*N byte buffer
** from the primary memory allocator and use that buffer
** with N lookaside slots of Z bytes each.
**
** {H14215} A successful call to
** [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where
** D is an open [database connection] and Z and N are zero shall
** disable the [lookaside memory allocator] for D.
**
**
*/
SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...);
/*
** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
** EXPERIMENTAL
**
** 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]. By creating an instance of this object
** and passing it to [sqlite3_config()] 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 a built-in memory allocator that is
** 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, xFree, and xRealloc methods must work like the
** malloc(), free(), and realloc() functions from the standard library.
**
** 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.
**
** 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.
*/
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 {H10160} <S20000>
** EXPERIMENTAL
**
** 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.
**
** <dl>
** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
** <dd>There are no arguments to this option. This option disables
** all mutexing and puts SQLite into a mode where it can only be used
** by a single thread.</dd>
**
** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
** <dd>There are no arguments to this option. This option 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. See the [threading mode]
** documentation for additional information.</dd>
**
** <dt>SQLITE_CONFIG_SERIALIZED</dt>
** <dd>There are no arguments to this option. 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.
** See the [threading mode] documentation for additional information.</dd>
**
** <dt>SQLITE_CONFIG_MALLOC</dt>
** <dd>This 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.</dd>
**
** <dt>SQLITE_CONFIG_GETMALLOC</dt>
** <dd>This 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.</dd>
**
** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
** <dd>This option takes single argument of type int, interpreted as a
** boolean, which enables or disables the collection of memory allocation
** statistics. When disabled, the following SQLite interfaces become
** non-operational:
** <ul>
** <li> [sqlite3_memory_used()]
** <li> [sqlite3_memory_highwater()]
** <li> [sqlite3_soft_heap_limit()]
** <li> [sqlite3_status()]
** </ul>
** </dd>
**
** <dt>SQLITE_CONFIG_SCRATCH</dt>
** <dd>This option specifies a static memory buffer that SQLite can use for
** scratch memory. There are three arguments: A pointer to the memory, the
** size of each scratch buffer (sz), and the number of buffers (N). The sz
** argument must be a multiple of 16. The sz parameter should be a few bytes
** larger than the actual scratch space required due internal overhead.
** The first
** argument should point to an allocation of at least sz*N bytes of memory.
** SQLite will use no more than one scratch buffer at once per thread, so
** N should be set to the expected maximum number of threads. The sz
** parameter should be 6 times the size of the largest database page size.
** Scratch buffers are used as part of the btree balance operation. If
** The btree balancer needs additional memory beyond what is provided by
** scratch buffers or if no scratch buffer space is specified, then SQLite
** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd>
**
** <dt>SQLITE_CONFIG_PAGECACHE</dt>
** <dd>This option specifies a static memory buffer that SQLite can use for
** the database page cache with the default page cache implemenation.
** This configuration should not be used if an application-define page
** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option.
** There are three arguments to this option: A pointer to the
** memory, the size of each page buffer (sz), and the number of pages (N).
** The sz argument must be a power of two between 512 and 32768. The first
** argument should point to an allocation of at least sz*N bytes of memory.
** SQLite will use the memory provided by the first argument to satisfy its
** memory needs for the first N pages that it adds to cache. If additional
** page cache memory is needed beyond what is provided by this option, then
** SQLite goes to [sqlite3_malloc()] for the additional storage space.
** The implementation might use one or more of the N buffers to hold
** memory accounting information. </dd>
**
** <dt>SQLITE_CONFIG_HEAP</dt>
** <dd>This 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_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
** There are three arguments: A 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 and either [SQLITE_ENABLE_MEMSYS3] or
** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
** allocator is engaged to handle all of SQLites memory allocation needs.</dd>
**
** <dt>SQLITE_CONFIG_MUTEX</dt>
** <dd>This 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.</dd>
**
** <dt>SQLITE_CONFIG_GETMUTEX</dt>
** <dd>This 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.</dd>
**
** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
** <dd>This option takes two arguments that determine the default
** memory allcation lookaside optimization. The first argument is the
** size of each lookaside buffer slot and the second is the number of
** slots allocated to each database connection.</dd>
**
** <dt>SQLITE_CONFIG_PCACHE</dt>
** <dd>This option takes a single argument which is a pointer to
** an [sqlite3_pcache_methods] object. This object specifies the interface
** to a custom page cache implementation. SQLite makes a copy of the
** object and uses it for page cache memory allocations.</dd>
**
** <dt>SQLITE_CONFIG_GETPCACHE</dt>
** <dd>This option takes a single argument which is a pointer to an
** [sqlite3_pcache_methods] object. SQLite copies of the current
** page cache implementation into that object.</dd>
**
** </dl>
*/
#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 /* void*, int sz, int N */
#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 /* sqlite3_pcache_methods* */
#define SQLITE_CONFIG_GETPCACHE 15 /* sqlite3_pcache_methods* */
/*
** CAPI3REF: Configuration Options {H10170} <S20000>
** EXPERIMENTAL
**
** 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.
**
** <dl>
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
** <dd>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 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 and 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.</dd>
**
** </dl>
*/
#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
/*
** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
**
** 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 considerations.
**
** INVARIANTS:
**
** {H12201} Each new [database connection] shall have the
** [extended result codes] feature disabled by default.
**
** {H12202} The [sqlite3_extended_result_codes(D,F)] interface shall enable
** [extended result codes] for the [database connection] D
** if the F parameter is true, or disable them if F is false.
*/
int sqlite3_extended_result_codes(sqlite3*, int onoff);
/*
** CAPI3REF: Last Insert Rowid {H12220} <S10700>
**
** Each entry in an SQLite table 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.
**
** This routine returns the [rowid] of the most recent
** successful [INSERT] into the database from the [database connection]
** in the first argument. If no successful [INSERT]s
** have ever occurred on that database connection, zero is returned.
**
** If an [INSERT] occurs within a trigger, then the [rowid] of the inserted
** row is returned by this routine as long as the trigger is running.
** But once the trigger terminates, the value returned by this routine
** reverts to the last value inserted before the trigger 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.
**
** INVARIANTS:
**
** {H12221} The [sqlite3_last_insert_rowid()] function shall return
** the [rowid]
** of the most recent successful [INSERT] performed on the same
** [database connection] and within the same or higher level
** trigger context, or zero if there have been no qualifying
** [INSERT] statements.
**
** {H12223} The [sqlite3_last_insert_rowid()] function shall return the
** same value when called from the same trigger context
** immediately before and after a [ROLLBACK].
**
** ASSUMPTIONS:
**
** {A12232} 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].
*/
sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
/*
** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
**
** This function returns the number of database rows that were changed
** or inserted or deleted by the most recently completed SQL statement
** on the [database connection] specified by the first parameter.
** Only changes that are directly specified by the [INSERT], [UPDATE],
** or [DELETE] statement are counted. Auxiliary changes caused by
** triggers are not counted. Use the [sqlite3_total_changes()] function
** to find the total number of changes including changes caused by triggers.
**
** A "row change" is a change to a single row of a single table
** caused by an INSERT, DELETE, or UPDATE statement. Rows that
** are changed as side effects of REPLACE constraint resolution,
** rollback, ABORT processing, DROP TABLE, or by any other
** mechanisms do not count as direct row changes.
**
** A "trigger context" is a scope of execution that begins and
** ends with the script of a trigger. Most SQL statements are
** evaluated outside of any trigger. This is the "top level"
** trigger context. If a trigger fires from the top level, a
** new trigger context is entered for the duration of that one
** trigger. Subtriggers create subcontexts for their duration.
**
** Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
** not create a new trigger context.
**
** This function returns the number of direct row changes in the
** most recent INSERT, UPDATE, or DELETE statement within the same
** trigger context.
**
** Thus, when called from the top level, this function returns the
** number of changes in the most recent INSERT, UPDATE, or DELETE
** that also occurred at the top level. Within the body of a trigger,
** the sqlite3_changes() interface can be called to find the number of
** changes in the most recently completed INSERT, UPDATE, or DELETE
** statement within the body of the same trigger.
** However, the number returned does not include changes
** caused by subtriggers since those have their own context.
**
** SQLite implements the command "DELETE FROM table" without a WHERE clause
** by dropping and recreating the table. Doing so is much faster than going
** through and deleting individual elements from the table. Because of this
** optimization, the deletions in "DELETE FROM table" are not row changes and
** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
** functions, regardless of the number of elements that were originally
** in the table. To get an accurate count of the number of rows deleted, use
** "DELETE FROM table WHERE 1" instead. Or recompile using the
** [SQLITE_OMIT_TRUNCATE_OPTIMIZATION] compile-time option to disable the
** optimization on all queries.
**
** INVARIANTS:
**
** {H12241} The [sqlite3_changes()] function shall return the number of
** row changes caused by the most recent INSERT, UPDATE,
** or DELETE statement on the same database connection and
** within the same or higher trigger context, or zero if there have
** not been any qualifying row changes.
**
** {H12243} Statements of the form "DELETE FROM tablename" with no
** WHERE clause shall cause subsequent calls to
** [sqlite3_changes()] to return zero, regardless of the
** number of rows originally in the table.
**
** ASSUMPTIONS:
**
** {A12252} 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.
*/
int sqlite3_changes(sqlite3*);
/*
** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600>
**
** This function returns the number of row changes caused by INSERT,
** UPDATE or DELETE statements since the [database connection] was opened.
** The count includes all changes from all trigger contexts. However,
** the count does not include changes used to implement REPLACE constraints,
** do rollbacks or ABORT processing, or DROP table processing.
** The changes are counted as soon as the statement that makes them is
** completed (when the statement handle is passed to [sqlite3_reset()] or
** [sqlite3_finalize()]).
**
** SQLite implements the command "DELETE FROM table" without a WHERE clause
** by dropping and recreating the table. (This is much faster than going
** through and deleting individual elements from the table.) Because of this
** optimization, the deletions in "DELETE FROM table" are not row changes and
** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
** functions, regardless of the number of elements that were originally
** in the table. To get an accurate count of the number of rows deleted, use
** "DELETE FROM table WHERE 1" instead. Or recompile using the
** [SQLITE_OMIT_TRUNCATE_OPTIMIZATION] compile-time option to disable the
** optimization on all queries.
**
** See also the [sqlite3_changes()] interface.
**
** INVARIANTS:
**
** {H12261} The [sqlite3_total_changes()] returns the total number
** of row changes caused by INSERT, UPDATE, and/or DELETE
** statements on the same [database connection], in any
** trigger context, since the database connection was created.
**
** {H12263} Statements of the form "DELETE FROM tablename" with no
** WHERE clause shall not change the value returned
** by [sqlite3_total_changes()].
**
** ASSUMPTIONS:
**
** {A12264} 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.
*/
int sqlite3_total_changes(sqlite3*);
/*
** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500>
**
** 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.
**
** A call to sqlite3_interrupt() has no effect on SQL statements
** that are started after sqlite3_interrupt() returns.
**
** INVARIANTS:
**
** {H12271} The [sqlite3_interrupt()] interface will force all running
** SQL statements associated with the same database connection
** to halt after processing at most one additional row of data.
**
** {H12272} Any SQL statement that is interrupted by [sqlite3_interrupt()]
** will return [SQLITE_INTERRUPT].
**
** ASSUMPTIONS:
**
** {A12279} If the database connection closes while [sqlite3_interrupt()]
** is running then bad things will likely happen.
*/
void sqlite3_interrupt(sqlite3*);
/*
** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200>
**
** These routines are useful for command-line input to determine if the
** currently entered text seems to form complete a SQL statement or
** if additional input is needed before sending the text into
** SQLite for parsing. These routines return true 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 fragment of a
** 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.
**
** These routines do not parse the SQL statements thus
** will not detect syntactically incorrect SQL.
**
** INVARIANTS:
**
** {H10511} A successful evaluation of [sqlite3_complete()] or
** [sqlite3_complete16()] functions shall
** return a numeric 1 if and only if the last non-whitespace
** token in their input is a semicolon that is not in between
** the BEGIN and END of a CREATE TRIGGER statement.
**
** {H10512} If a memory allocation error occurs during an invocation
** of [sqlite3_complete()] or [sqlite3_complete16()] then the
** routine shall return [SQLITE_NOMEM].
**
** ASSUMPTIONS:
**
** {A10512} The input to [sqlite3_complete()] must be a zero-terminated
** UTF-8 string.
**
** {A10513} The input to [sqlite3_complete16()] must be a zero-terminated
** UTF-16 string in native byte order.
*/
int sqlite3_complete(const char *sql);
int sqlite3_complete16(const void *sql);
/*
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400>
**
** This routine sets a callback function that might be invoked whenever
** an attempt is made to open a database table that another thread
** or process has locked.
**
** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
** is returned immediately upon encountering the lock. If the busy callback
** is not NULL, then the callback will be invoked with two arguments.
**
** The first argument to the handler is a copy of the void* pointer which
** is the third argument to sqlite3_busy_handler(). The second argument to
** the handler callback is the number of times that the busy handler has
** been invoked for this locking event. If the
** busy callback returns 0, then no additional attempts are made to
** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
** If the callback returns non-zero, then another attempt
** is made to open the database for reading 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]
** or [SQLITE_IOERR_BLOCKED] 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.
**
** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
** when SQLite is in the middle of a large transaction where all the
** changes will not fit into the in-memory cache. SQLite will
** already hold a RESERVED lock on the database file, but it needs
** to promote this lock to EXCLUSIVE so that it can spill cache
** pages into the database file without harm to concurrent
** readers. If it is unable to promote the lock, then the in-memory
** cache will be left in an inconsistent state and so the error
** code is promoted from the relatively benign [SQLITE_BUSY] to
** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion
** forces an automatic rollback of the changes. See the
** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
** CorruptionFollowingBusyError</a> wiki page for a discussion of why
** this is important.
**
** 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()]
** will also set or clear the busy handler.
**
** The busy callback should not take any actions which modify the
** database connection that invoked the busy handler. Any such actions
** result in undefined behavior.
**
** INVARIANTS:
**
** {H12311} The [sqlite3_busy_handler(D,C,A)] function shall replace
** busy callback in the [database connection] D with a new
** a new busy handler C and application data pointer A.
**
** {H12312} Newly created [database connections] shall have a busy
** handler of NULL.
**
** {H12314} When two or more [database connections] share a
** [sqlite3_enable_shared_cache | common cache],
** the busy handler for the database connection currently using
** the cache shall be invoked when the cache encounters a lock.
**
** {H12316} If a busy handler callback returns zero, then the SQLite interface
** that provoked the locking event shall return [SQLITE_BUSY].
**
** {H12318} SQLite shall invokes the busy handler with two arguments which
** are a copy of the pointer supplied by the 3rd parameter to
** [sqlite3_busy_handler()] and a count of the number of prior
** invocations of the busy handler for the same locking event.
**
** ASSUMPTIONS:
**
** {A12319} A busy handler must not close the database connection
** or [prepared statement] that invoked the busy handler.
*/
int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
/*
** CAPI3REF: Set A Busy Timeout {H12340} <S40410>
**
** 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. {H12343} After "ms" milliseconds of sleeping,
** the handler returns 0 which causes [sqlite3_step()] to return
** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
**
** 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] any any given moment. If another busy handler
** was defined (using [sqlite3_busy_handler()]) prior to calling
** this routine, that other busy handler is cleared.
**
** INVARIANTS:
**
** {H12341} The [sqlite3_busy_timeout()] function shall override any prior
** [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting
** on the same [database connection].
**
** {H12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than
** or equal to zero, then the busy handler shall be cleared so that
** all subsequent locking events immediately return [SQLITE_BUSY].
**
** {H12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive
** number N, then a busy handler shall be set that repeatedly calls
** the xSleep() method in the [sqlite3_vfs | VFS interface] until
** either the lock clears or until the cumulative sleep time
** reported back by xSleep() exceeds N milliseconds.
*/
int sqlite3_busy_timeout(sqlite3*, int ms);
/*
** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000>
**
** Definition: A <b>result table</b> 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:
**
** <blockquote><pre>
** Name | Age
** -----------------------
** Alice | 43
** Bob | 28
** Cindy | 21
** </pre></blockquote>
**
** 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:
**
** <blockquote><pre>
** azResult&#91;0] = "Name";
** azResult&#91;1] = "Age";
** azResult&#91;2] = "Alice";
** azResult&#91;3] = "43";
** azResult&#91;4] = "Bob";
** azResult&#91;5] = "28";
** azResult&#91;6] = "Cindy";
** azResult&#91;7] = "21";
** </pre></blockquote>
**
** The sqlite3_get_table() function evaluates one or more
** semicolon-separated SQL statements in the zero-terminated UTF-8
** string of its 2nd parameter. It returns a result table to the
** pointer given in its 3rd parameter.
**
** After the calling function has finished using the result, it should
** pass the pointer to the result table 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()].
**
** INVARIANTS:
**
** {H12371} If a [sqlite3_get_table()] fails a memory allocation, then
** it shall free the result table under construction, abort the
** query in process, skip any subsequent queries, set the
** *pazResult output pointer to NULL and return [SQLITE_NOMEM].
**
** {H12373} If the pnColumn parameter to [sqlite3_get_table()] is not NULL
** then a successful invocation of [sqlite3_get_table()] shall
** write the number of columns in the
** result set of the query into *pnColumn.
**
** {H12374} If the pnRow parameter to [sqlite3_get_table()] is not NULL
** then a successful invocation of [sqlite3_get_table()] shall
** writes the number of rows in the
** result set of the query into *pnRow.
**
** {H12376} A successful invocation of [sqlite3_get_table()] that computes
** N rows of result with C columns per row shall make *pazResult
** point to an array of pointers to (N+1)*C strings where the first
** C strings are column names as obtained from
** [sqlite3_column_name()] and the rest are column result values
** obtained from [sqlite3_column_text()].
**
** {H12379} The values in the pazResult array returned by [sqlite3_get_table()]
** shall remain valid until cleared by [sqlite3_free_table()].
**
** {H12382} When an error occurs during evaluation of [sqlite3_get_table()]
** the function shall set *pazResult to NULL, write an error message
** into memory obtained from [sqlite3_malloc()], make
** **pzErrmsg point to that error message, and return a
** appropriate [error code].
*/
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 */
);
void sqlite3_free_table(char **result);
/*
** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000>
**
** These routines are workalikes of the "printf()" family of functions
** from the standard C library.
**
** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
** results into memory obtained from [sqlite3_malloc()].
** The strings returned by these two routines should be
** released by [sqlite3_free()]. Both routines return a
** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
** memory to hold the resulting string.
**
** In 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.
**
** These routines all implement some additional formatting
** options that are useful for constructing SQL statements.
** All of the usual printf() formatting options apply. In addition, there
** is are "%q", "%Q", and "%z" options.
**
** The %q option works like %s in that it substitutes a null-terminated
** string from the argument list. But %q also doubles every '\'' character.
** %q is designed for use inside a string literal. By doubling each '\''
** character it escapes that character and allows it to be inserted into
** the string.
**
** For example, assume the string variable zText contains text as follows:
**
** <blockquote><pre>
** char *zText = "It's a happy day!";
** </pre></blockquote>
**
** One can use this text in an SQL statement as follows:
**
** <blockquote><pre>
** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
** sqlite3_exec(db, zSQL, 0, 0, 0);
** sqlite3_free(zSQL);
** </pre></blockquote>
**
** Because the %q format string is used, the '\'' character in zText
** is escaped and the SQL generated is as follows:
**
** <blockquote><pre>
** INSERT INTO table1 VALUES('It''s a happy day!')
** </pre></blockquote>
**
** This is correct. Had we used %s instead of %q, the generated SQL
** would have looked like this:
**
** <blockquote><pre>
** INSERT INTO table1 VALUES('It's a happy day!');
** </pre></blockquote>
**
** This second example is an SQL syntax error. As a general rule you should
** always use %q instead of %s when inserting text into a string literal.
**
** The %Q option works like %q except it also adds single quotes around
** the outside of the total string. Additionally, if the parameter in the
** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
** single quotes) in place of the %Q option. So, for example, one could say:
**
** <blockquote><pre>
** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
** sqlite3_exec(db, zSQL, 0, 0, 0);
** sqlite3_free(zSQL);
** </pre></blockquote>
**
** The code above will render a correct SQL statement in the zSQL
** variable even if the zText variable is a NULL pointer.
**
** The "%z" formatting option works exactly like "%s" with the
** addition that after the string has been read and copied into
** the result, [sqlite3_free()] is called on the input string. {END}
**
** INVARIANTS:
**
** {H17403} The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces
** return either pointers to zero-terminated UTF-8 strings held in
** memory obtained from [sqlite3_malloc()] or NULL pointers if
** a call to [sqlite3_malloc()] fails.
**
** {H17406} The [sqlite3_snprintf()] interface writes a zero-terminated
** UTF-8 string into the buffer pointed to by the second parameter
** provided that the first parameter is greater than zero.
**
** {H17407} The [sqlite3_snprintf()] interface does not write slots of
** its output buffer (the second parameter) outside the range
** of 0 through N-1 (where N is the first parameter)
** regardless of the length of the string
** requested by the format specification.
*/
char *sqlite3_mprintf(const char*,...);
char *sqlite3_vmprintf(const char*, va_list);
char *sqlite3_snprintf(int,char*,const char*, ...);
/*
** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000>
**
** 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.
**
** 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() interface attempts to resize a
** prior memory allocation to be at least N bytes, where N is the
** second parameter. The memory allocation to be resized is the first
** parameter. If the first parameter to sqlite3_realloc()
** is a NULL pointer then its behavior is identical to calling
** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
** If the second parameter to sqlite3_realloc() is zero or
** negative then the behavior is exactly the same as calling
** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
** sqlite3_realloc() returns a pointer to a memory allocation
** of at least N bytes in size or NULL if sufficient memory is unavailable.
** 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() and the prior allocation is freed.
** If sqlite3_realloc() returns NULL, then the prior allocation
** is not freed.
**
** The memory returned by sqlite3_malloc() and sqlite3_realloc()
** is always aligned to at least an 8 byte boundary. {END}
**
** The default implementation of the memory allocation subsystem uses
** the malloc(), realloc() and free() provided by the standard C library.
** {H17382} However, if SQLite is compiled with the
** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i>
** is an integer), then SQLite create a static array of at least
** <i>NNN</i> bytes in size and uses that array for all of its dynamic
** memory allocation needs. {END} Additional memory allocator options
** may be added in future releases.
**
** 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.
**
** The Windows OS interface layer calls
** 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 are detected, but
** they are reported back as [SQLITE_CANTOPEN] or
** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
**
** INVARIANTS:
**
** {H17303} The [sqlite3_malloc(N)] interface returns either a pointer to
** a newly checked-out block of at least N bytes of memory
** that is 8-byte aligned, or it returns NULL if it is unable
** to fulfill the request.
**
** {H17304} The [sqlite3_malloc(N)] interface returns a NULL pointer if
** N is less than or equal to zero.
**
** {H17305} The [sqlite3_free(P)] interface releases memory previously
** returned from [sqlite3_malloc()] or [sqlite3_realloc()],
** making it available for reuse.
**
** {H17306} A call to [sqlite3_free(NULL)] is a harmless no-op.
**
** {H17310} A call to [sqlite3_realloc(0,N)] is equivalent to a call
** to [sqlite3_malloc(N)].
**
** {H17312} A call to [sqlite3_realloc(P,0)] is equivalent to a call
** to [sqlite3_free(P)].
**
** {H17315} The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()],
** and [sqlite3_free()] for all of its memory allocation and
** deallocation needs.
**
** {H17318} The [sqlite3_realloc(P,N)] interface returns either a pointer
** to a block of checked-out memory of at least N bytes in size
** that is 8-byte aligned, or a NULL pointer.
**
** {H17321} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
** copies the first K bytes of content from P into the newly
** allocated block, where K is the lesser of N and the size of
** the buffer P.
**
** {H17322} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
** releases the buffer P.
**
** {H17323} When [sqlite3_realloc(P,N)] returns NULL, the buffer P is
** not modified or released.
**
** ASSUMPTIONS:
**
** {A17350} 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.
**
** {A17351} 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()].
*/
void *sqlite3_malloc(int);
void *sqlite3_realloc(void*, int);
void sqlite3_free(void*);
/*
** CAPI3REF: Memory Allocator Statistics {H17370} <S30210>
**
** 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.
**
** INVARIANTS:
**
** {H17371} The [sqlite3_memory_used()] routine returns the number of bytes
** of memory currently outstanding (malloced but not freed).
**
** {H17373} The [sqlite3_memory_highwater()] routine returns the maximum
** value of [sqlite3_memory_used()] since the high-water mark
** was last reset.
**
** {H17374} 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.
**
** {H17375} 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.
*/
sqlite3_int64 sqlite3_memory_used(void);
sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
/*
** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000>
**
** 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 first time this routine is invoked (either internally or by
** the application) the PRNG is seeded using randomness obtained
** from the xRandomness method of the default [sqlite3_vfs] object.
** On all subsequent invocations, the pseudo-randomness is generated
** internally and without recourse to the [sqlite3_vfs] xRandomness
** method.
**
** INVARIANTS:
**
** {H17392} The [sqlite3_randomness(N,P)] interface writes N bytes of
** high-quality pseudo-randomness into buffer P.
*/
void sqlite3_randomness(int N, void *P);
/*
** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100>
**
** This routine registers a 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_prepare16()] and [sqlite3_prepare16_v2()]. 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. If the authorizer 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.
**
** 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 zero-terminated strings that contain additional
** details about the action to be authorized.
**
** 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 reprepared 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()].
**
** INVARIANTS:
**
** {H12501} The [sqlite3_set_authorizer(D,...)] interface registers a
** authorizer callback with database connection D.
**
** {H12502} The authorizer callback is invoked as SQL statements are
** being parseed and compiled.
**
** {H12503} If the authorizer callback returns any value other than
** [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY], then
** the application interface call that caused
** the authorizer callback to run shall fail with an
** [SQLITE_ERROR] error code and an appropriate error message.
**
** {H12504} When the authorizer callback returns [SQLITE_OK], the operation
** described is processed normally.
**
** {H12505} When the authorizer callback returns [SQLITE_DENY], the
** application interface call that caused the
** authorizer callback to run shall fail
** with an [SQLITE_ERROR] error code and an error message
** explaining that access is denied.
**
** {H12506} If the authorizer code (the 2nd parameter to the authorizer
** callback) is [SQLITE_READ] and the authorizer callback returns
** [SQLITE_IGNORE], then the prepared statement is constructed to
** insert a NULL value in place of the table column that would have
** been read if [SQLITE_OK] had been returned.
**
** {H12507} If the authorizer code (the 2nd parameter to the authorizer
** callback) is anything other than [SQLITE_READ], then
** a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY].
**
** {H12510} The first parameter to the authorizer callback is a copy of
** the third parameter to the [sqlite3_set_authorizer()] interface.
**
** {H12511} The second parameter to the callback is an integer
** [SQLITE_COPY | action code] that specifies the particular action
** to be authorized.
**
** {H12512} The third through sixth parameters to the callback are
** zero-terminated strings that contain
** additional details about the action to be authorized.
**
** {H12520} Each call to [sqlite3_set_authorizer()] overrides
** any previously installed authorizer.
**
** {H12521} A NULL authorizer means that no authorization
** callback is invoked.
**
** {H12522} The default authorizer is NULL.
*/
int sqlite3_set_authorizer(
sqlite3*,
int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
void *pUserData
);
/*
** CAPI3REF: Authorizer Return Codes {H12590} <H12500>
**
** 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.
*/
#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 {H12550} <H12500>
**
** 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.
**
** INVARIANTS:
**
** {H12551} The second parameter to an
** [sqlite3_set_authorizer | authorizer callback] shall be an integer
** [SQLITE_COPY | authorizer code] that specifies what action
** is being authorized.
**
** {H12552} The 3rd and 4th parameters to the
** [sqlite3_set_authorizer | authorization callback]
** shall be parameters or NULL depending on which
** [SQLITE_COPY | authorizer code] is used as the second parameter.
**
** {H12553} The 5th parameter to the
** [sqlite3_set_authorizer | authorizer callback] shall be the name
** of the database (example: "main", "temp", etc.) if applicable.
**
** {H12554} The 6th parameter to the
** [sqlite3_set_authorizer | authorizer callback] shall be 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 */
/*
** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400>
** EXPERIMENTAL
**
** 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 callback returns a UTF-8 rendering of the SQL statement text
** as the statement first begins executing. Additional callbacks occur
** as each triggered subprogram is entered. The callbacks for triggers
** contain a UTF-8 SQL comment that identifies the trigger.
**
** 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.
**
** INVARIANTS:
**
** {H12281} The callback function registered by [sqlite3_trace()]
** shall be invoked
** whenever an SQL statement first begins to execute and
** whenever a trigger subprogram first begins to run.
**
** {H12282} Each call to [sqlite3_trace()] shall override the previously
** registered trace callback.
**
** {H12283} A NULL trace callback shall disable tracing.
**
** {H12284} The first argument to the trace callback shall be a copy of
** the pointer which was the 3rd argument to [sqlite3_trace()].
**
** {H12285} The second argument to the trace callback is a
** zero-terminated UTF-8 string containing the original text
** of the SQL statement as it was passed into [sqlite3_prepare_v2()]
** or the equivalent, or an SQL comment indicating the beginning
** of a trigger subprogram.
**
** {H12287} The callback function registered by [sqlite3_profile()] is invoked
** as each SQL statement finishes.
**
** {H12288} The first parameter to the profile callback is a copy of
** the 3rd parameter to [sqlite3_profile()].
**
** {H12289} The second parameter to the profile callback is a
** zero-terminated UTF-8 string that contains the complete text of
** the SQL statement as it was processed by [sqlite3_prepare_v2()]
** or the equivalent.
**
** {H12290} The third parameter to the profile callback is an estimate
** of the number of nanoseconds of wall-clock time required to
** run the SQL statement from start to finish.
*/
SQLITE_EXPERIMENTAL void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
/*
** CAPI3REF: Query Progress Callbacks {H12910} <S60400>
**
** This routine configures a callback function - the
** progress callback - that is invoked periodically during long
** running calls to [sqlite3_exec()], [sqlite3_step()] and
** [sqlite3_get_table()]. An example use for this
** interface is to keep a GUI updated during a large query.
**
** 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 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.
**
** INVARIANTS:
**
** {H12911} The callback function registered by sqlite3_progress_handler()
** is invoked periodically during long running calls to
** [sqlite3_step()].
**
** {H12912} The progress callback is invoked once for every N virtual
** machine opcodes, where N is the second argument to
** the [sqlite3_progress_handler()] call that registered
** the callback. If N is less than 1, sqlite3_progress_handler()
** acts as if a NULL progress handler had been specified.
**
** {H12913} The progress callback itself is identified by the third
** argument to sqlite3_progress_handler().
**
** {H12914} The fourth argument to sqlite3_progress_handler() is a
** void pointer passed to the progress callback
** function each time it is invoked.
**
** {H12915} If a call to [sqlite3_step()] results in fewer than N opcodes
** being executed, then the progress callback is never invoked.
**
** {H12916} Every call to [sqlite3_progress_handler()]
** overwrites any previously registered progress handler.
**
** {H12917} If the progress handler callback is NULL then no progress
** handler is invoked.
**
** {H12918} If the progress callback returns a result other than 0, then
** the behavior is a if [sqlite3_interrupt()] had been called.
** <S30500>
*/
void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
/*
** CAPI3REF: Opening A New Database Connection {H12700} <S40200>
**
** These routines open an SQLite database file whose name is given 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.
**
** The default encoding for the database will be UTF-8 if
** sqlite3_open() or sqlite3_open_v2() is called and
** UTF-16 in the native byte order if sqlite3_open16() is used.
**
** 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 can take one of
** the following three values, optionally combined with the
** [SQLITE_OPEN_NOMUTEX] or [SQLITE_OPEN_FULLMUTEX] flags:
**
** <dl>
** <dt>[SQLITE_OPEN_READONLY]</dt>
** <dd>The database is opened in read-only mode. If the database does not
** already exist, an error is returned.</dd>
**
** <dt>[SQLITE_OPEN_READWRITE]</dt>
** <dd>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.</dd>
**
** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
** <dd>The database is opened for reading and writing, and is creates it if
** it does not already exist. This is the behavior that is always used for
** sqlite3_open() and sqlite3_open16().</dd>
** </dl>
**
** If the 3rd parameter to sqlite3_open_v2() is not one of the
** combinations shown above or one of the combinations shown above combined
** with the [SQLITE_OPEN_NOMUTEX] or [SQLITE_OPEN_FULLMUTEX] flags,
** 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.
**
** 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.
**
** 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.
**
** <b>Note to Windows users:</b> 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().
**
** INVARIANTS:
**
** {H12701} The [sqlite3_open()], [sqlite3_open16()], and
** [sqlite3_open_v2()] interfaces create a new
** [database connection] associated with
** the database file given in their first parameter.
**
** {H12702} 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()].
**
** {H12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()],
** or [sqlite3_open_v2()] writes a pointer to a new
** [database connection] into *ppDb.
**
** {H12704} The [sqlite3_open()], [sqlite3_open16()], and
** [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success,
** or an appropriate [error code] on failure.
**
** {H12706} The default text encoding for a new database created using
** [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8.
**
** {H12707} The default text encoding for a new database created using
** [sqlite3_open16()] will be UTF-16.
**
** {H12709} The [sqlite3_open(F,D)] interface is equivalent to
** [sqlite3_open_v2(F,D,G,0)] where the G parameter is
** [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE].
**
** {H12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
** bit value [SQLITE_OPEN_READONLY] then the database is opened
** for reading only.
**
** {H12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
** bit value [SQLITE_OPEN_READWRITE] then the database is opened
** reading and writing if possible, or for reading only if the
** file is write protected by the operating system.
**
** {H12713} If the G parameter to [sqlite3_open_v2(F,D,G,V)] omits the
** bit value [SQLITE_OPEN_CREATE] and the database does not
** previously exist, an error is returned.
**
** {H12714} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
** bit value [SQLITE_OPEN_CREATE] and the database does not
** previously exist, then an attempt is made to create and
** initialize the database.
**
** {H12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()],
** or [sqlite3_open_v2()] is ":memory:", then an private,
** ephemeral, in-memory database is created for the connection.
** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
** in sqlite3_open_v2()?</todo>
**
** {H12719} If the filename is NULL or an empty string, then a private,
** ephemeral on-disk database will be created.
** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
** in sqlite3_open_v2()?</todo>
**
** {H12721} The [database connection] created by [sqlite3_open_v2(F,D,G,V)]
** will use the [sqlite3_vfs] object identified by the V parameter,
** or the default [sqlite3_vfs] object if V is a NULL pointer.
**
** {H12723} Two [database connections] will share a common cache if both were
** opened with the same VFS while [shared cache mode] was enabled and
** if both filenames compare equal using memcmp() after having been
** processed by the [sqlite3_vfs | xFullPathname] method of the VFS.
*/
int sqlite3_open(
const char *filename, /* Database filename (UTF-8) */
sqlite3 **ppDb /* OUT: SQLite db handle */
);
int sqlite3_open16(
const void *filename, /* Database filename (UTF-16) */
sqlite3 **ppDb /* OUT: SQLite db handle */
);
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: Error Codes And Messages {H12800} <S60200>
**
** The sqlite3_errcode() interface returns the numeric [result code] or
** [extended result code] for the most recent failed sqlite3_* API call
** associated with a [database connection]. If a prior API call failed
** but the most recent API call succeeded, the return value from
** sqlite3_errcode() is undefined. 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 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.
**
** 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.
**
** INVARIANTS:
**
** {H12801} The [sqlite3_errcode(D)] interface returns the numeric
** [result code] or [extended result code] for the most recently
** failed interface call associated with the [database connection] D.
**
** {H12802} The [sqlite3_extended_errcode(D)] interface returns the numeric
** [extended result code] for the most recently
** failed interface call associated with the [database connection] D.
**
** {H12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
** interfaces return English-language text that describes
** the error in the mostly recently failed interface call,
** encoded as either UTF-8 or UTF-16 respectively.
**
** {H12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
** are valid until the next SQLite interface call.
**
** {H12808} Calls to API routines that do not return an error code
** (example: [sqlite3_data_count()]) do not
** change the error code or message returned by
** [sqlite3_errcode()], [sqlite3_extended_errcode()],
** [sqlite3_errmsg()], or [sqlite3_errmsg16()].
**
** {H12809} Interfaces that are not associated with a specific
** [database connection] (examples:
** [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()]
** do not change the values returned by
** [sqlite3_errcode()], [sqlite3_extended_errcode()],
** [sqlite3_errmsg()], or [sqlite3_errmsg16()].
*/
int sqlite3_errcode(sqlite3 *db);
int sqlite3_extended_errcode(sqlite3 *db);
const char *sqlite3_errmsg(sqlite3*);
const void *sqlite3_errmsg16(sqlite3*);
/*
** CAPI3REF: SQL Statement Object {H13000} <H13010>
** KEYWORDS: {prepared statement} {prepared statements}
**
** An instance of this object represents a single SQL statement.
** This object is variously known as a "prepared statement" or a
** "compiled SQL statement" or simply as a "statement".
**
** The life of a statement object goes something like this:
**
** <ol>
** <li> Create the object using [sqlite3_prepare_v2()] or a related
** function.
** <li> Bind values to [host parameters] using the sqlite3_bind_*()
** interfaces.
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
** <li> Reset the statement using [sqlite3_reset()] then go back
** to step 2. Do this zero or more times.
** <li> Destroy the object using [sqlite3_finalize()].
** </ol>
**
** Refer to documentation on individual methods above for additional
** information.
*/
typedef struct sqlite3_stmt sqlite3_stmt;
/*
** CAPI3REF: Run-time Limits {H12760} <S20600>
**
** 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. The function returns the old limit.
**
** If the new limit is a negative number, the limit is unchanged.
** For the limit category of SQLITE_LIMIT_XYZ there is a hard upper
** bound set by a compile-time C preprocessor macro named SQLITE_MAX_XYZ.
** (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 limit.
**
** 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
** webbrowser 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.
**
** INVARIANTS:
**
** {H12762} A successful call to [sqlite3_limit(D,C,V)] where V is
** positive changes the limit on the size of construct C in the
** [database connection] D to the lesser of V and the hard upper
** bound on the size of C that is set at compile-time.
**
** {H12766} A successful call to [sqlite3_limit(D,C,V)] where V is negative
** leaves the state of the [database connection] D unchanged.
**
** {H12769} A successful call to [sqlite3_limit(D,C,V)] returns the
** value of the limit on the size of construct C in the
** [database connection] D as it was prior to the call.
*/
int sqlite3_limit(sqlite3*, int id, int newVal);
/*
** CAPI3REF: Run-Time Limit Categories {H12790} <H12760>
** KEYWORDS: {limit category} {limit categories}
**
** These constants define various aspects of a [database connection]
** that can be limited in size by calls to [sqlite3_limit()].
** The meanings of the various limits are as follows:
**
** <dl>
** <dt>SQLITE_LIMIT_LENGTH</dt>
** <dd>The maximum size of any string or BLOB or table row.<dd>
**
** <dt>SQLITE_LIMIT_SQL_LENGTH</dt>
** <dd>The maximum length of an SQL statement.</dd>
**
** <dt>SQLITE_LIMIT_COLUMN</dt>
** <dd>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.</dd>
**
** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
** <dd>The maximum depth of the parse tree on any expression.</dd>
**
** <dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
** <dd>The maximum number of terms in a compound SELECT statement.</dd>
**
** <dt>SQLITE_LIMIT_VDBE_OP</dt>
** <dd>The maximum number of instructions in a virtual machine program
** used to implement an SQL statement.</dd>
**
** <dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
** <dd>The maximum number of arguments on a function.</dd>
**
** <dt>SQLITE_LIMIT_ATTACHED</dt>
** <dd>The maximum number of attached databases.</dd>
**
** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
** <dd>The maximum length of the pattern argument to the LIKE or
** GLOB operators.</dd>
**
** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
** <dd>The maximum number of variables in an SQL statement that can
** be bound.</dd>
** </dl>
*/
#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
/*
** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
** KEYWORDS: {SQL statement compiler}
**
** To execute an SQL query, it must first be compiled into a byte-code
** program using one of these routines.
**
** The first argument, "db", is a [database connection] obtained from a
** prior call to [sqlite3_open()], [sqlite3_open_v2()] or [sqlite3_open16()].
**
** The second argument, "zSql", is the statement to be compiled, encoded
** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
** use UTF-16.
**
** If the nByte argument is less than zero, then zSql is read up to the
** first zero terminator. If nByte is non-negative, then it is the maximum
** number of bytes read from zSql. When nByte is non-negative, the
** zSql string ends at either the first '\000' or '\u0000' character or
** the nByte-th byte, whichever comes first. If the caller knows
** that the supplied string is nul-terminated, then there is a small
** performance advantage to be gained by passing an nByte parameter that
** is equal to the number of bytes in the input string <i>including</i>
** the nul-terminator bytes.
**
** *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.
** {A13018} The calling procedure is responsible for deleting the compiled
** SQL statement using [sqlite3_finalize()] after it has finished with it.
**
** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
**
** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
** recommended for all new programs. The two older interfaces are retained
** for backwards compatibility, but their use is discouraged.
** In the "v2" 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 a differently in two ways:
**
** <ol>
** <li>
** 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. If the schema has changed in
** a way that makes the statement no longer valid, [sqlite3_step()] will still
** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
** error go away. Note: use [sqlite3_errmsg()] to find the text
** of the parsing error that results in an [SQLITE_SCHEMA] return.
** </li>
**
** <li>
** 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 you 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.
** </li>
** </ol>
**
** INVARIANTS:
**
** {H13011} The [sqlite3_prepare(db,zSql,...)] and
** [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the
** text in their zSql parameter as UTF-8.
**
** {H13012} The [sqlite3_prepare16(db,zSql,...)] and
** [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the
** text in their zSql parameter as UTF-16 in the native byte order.
**
** {H13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
** and its variants is less than zero, the SQL text is
** read from zSql is read up to the first zero terminator.
**
** {H13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
** and its variants is non-negative, then at most nBytes bytes of
** SQL text is read from zSql.
**
** {H13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants
** if the zSql input text contains more than one SQL statement
** and pzTail is not NULL, then *pzTail is made to point to the
** first byte past the end of the first SQL statement in zSql.
** <todo>What does *pzTail point to if there is one statement?</todo>
**
** {H13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)]
** or one of its variants writes into *ppStmt a pointer to a new
** [prepared statement] or a pointer to NULL if zSql contains
** nothing other than whitespace or comments.
**
** {H13019} The [sqlite3_prepare_v2()] interface and its variants return
** [SQLITE_OK] or an appropriate [error code] upon failure.
**
** {H13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its
** variants returns an error (any value other than [SQLITE_OK]),
** they first set *ppStmt to NULL.
*/
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 */
);
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 */
);
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 */
);
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 */
);
/*
** CAPI3REF: Retrieving Statement SQL {H13100} <H13000>
**
** This interface can be used to retrieve a saved copy of the original
** SQL text used to create a [prepared statement] if that statement was
** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
**
** INVARIANTS:
**
** {H13101} If the [prepared statement] passed as the argument to
** [sqlite3_sql()] was compiled using either [sqlite3_prepare_v2()] or
** [sqlite3_prepare16_v2()], then [sqlite3_sql()] returns
** a pointer to a zero-terminated string containing a UTF-8 rendering
** of the original SQL statement.
**
** {H13102} If the [prepared statement] passed as the argument to
** [sqlite3_sql()] was compiled using either [sqlite3_prepare()] or
** [sqlite3_prepare16()], then [sqlite3_sql()] returns a NULL pointer.
**
** {H13103} The string returned by [sqlite3_sql(S)] is valid until the
** [prepared statement] S is deleted using [sqlite3_finalize(S)].
*/
const char *sqlite3_sql(sqlite3_stmt *pStmt);
/*
** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200>
** 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 terms "protected" and "unprotected" refer to whether or not
** a mutex is held. A 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 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 with
** [sqlite3_result_value()] and [sqlite3_bind_value()].
** The [sqlite3_value_blob | sqlite3_value_type()] family of
** interfaces require protected sqlite3_value objects.
*/
typedef struct Mem sqlite3_value;
/*
** CAPI3REF: SQL Function Context Object {H16001} <S20200>
**
** 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 {H13500} <S70300>
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
**
** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
** literals may be replaced by a parameter in one of these forms:
**
** <ul>
** <li> ?
** <li> ?NNN
** <li> :VVV
** <li> @VVV
** <li> $VVV
** </ul>
**
** In the parameter forms shown above NNN is an integer literal,
** and VVV is an alpha-numeric parameter name. 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.
**
** 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 <u>bytes</u> in the value, not the number of characters.
** If the fourth parameter is negative, the length of the string is
** the number of bytes up to the first zero terminator.
**
** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
** string after SQLite has finished with it. 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 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_*() routines must be called after
** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
** before [sqlite3_step()].
** Bindings are not cleared by the [sqlite3_reset()] routine.
** Unbound parameters are interpreted as NULL.
**
** These routines return [SQLITE_OK] on success or an error code if
** anything goes wrong. [SQLITE_RANGE] is returned if the parameter
** index is out of range. [SQLITE_NOMEM] is returned if malloc() fails.
** [SQLITE_MISUSE] might be returned if these routines are called on a
** virtual machine that is the wrong state or which has already been finalized.
** Detection of misuse is unreliable. Applications should not depend
** on SQLITE_MISUSE returns. SQLITE_MISUSE is intended to indicate a
** a logic error in the application. Future versions of SQLite might
** panic rather than return SQLITE_MISUSE.
**
** See also: [sqlite3_bind_parameter_count()],
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
**
** INVARIANTS:
**
** {H13506} The [SQL statement compiler] recognizes tokens of the forms
** "?", "?NNN", "$VVV", ":VVV", and "@VVV" as SQL parameters,
** where NNN is any sequence of one or more digits
** and where VVV is any sequence of one or more alphanumeric
** characters or "::" optionally followed by a string containing
** no spaces and contained within parentheses.
**
** {H13509} The initial value of an SQL parameter is NULL.
**
** {H13512} The index of an "?" SQL parameter is one larger than the
** largest index of SQL parameter to the left, or 1 if
** the "?" is the leftmost SQL parameter.
**
** {H13515} The index of an "?NNN" SQL parameter is the integer NNN.
**
** {H13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is
** the same as the index of leftmost occurrences of the same
** parameter, or one more than the largest index over all
** parameters to the left if this is the first occurrence
** of this parameter, or 1 if this is the leftmost parameter.
**
** {H13521} The [SQL statement compiler] fails with an [SQLITE_RANGE]
** error if the index of an SQL parameter is less than 1
** or greater than the compile-time SQLITE_MAX_VARIABLE_NUMBER
** parameter.
**
** {H13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)]
** associate the value V with all SQL parameters having an
** index of N in the [prepared statement] S.
**
** {H13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)]
** override prior calls with the same values of S and N.
**
** {H13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)]
** persist across calls to [sqlite3_reset(S)].
**
** {H13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
** [sqlite3_bind_text(S,N,V,L,D)], or
** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L
** bytes of the BLOB or string pointed to by V, when L
** is non-negative.
**
** {H13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or
** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters
** from V through the first zero character when L is negative.
**
** {H13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
** [sqlite3_bind_text(S,N,V,L,D)], or
** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
** constant [SQLITE_STATIC], SQLite assumes that the value V
** is held in static unmanaged space that will not change
** during the lifetime of the binding.
**
** {H13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
** [sqlite3_bind_text(S,N,V,L,D)], or
** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
** constant [SQLITE_TRANSIENT], the routine makes a
** private copy of the value V before it returns.
**
** {H13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
** [sqlite3_bind_text(S,N,V,L,D)], or
** [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to
** a function, SQLite invokes that function to destroy the
** value V after it has finished using the value V.
**
** {H13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound
** is a BLOB of L bytes, or a zero-length BLOB if L is negative.
**
** {H13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may
** be either a [protected sqlite3_value] object or an
** [unprotected sqlite3_value] object.
*/
int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
int sqlite3_bind_double(sqlite3_stmt*, int, double);
int sqlite3_bind_int(sqlite3_stmt*, int, int);
int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
int sqlite3_bind_null(sqlite3_stmt*, int);
int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
/*
** CAPI3REF: Number Of SQL Parameters {H13600} <S70300>
**
** 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 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()].
**
** INVARIANTS:
**
** {H13601} The [sqlite3_bind_parameter_count(S)] interface returns
** the largest index of all SQL parameters in the
** [prepared statement] S, or 0 if S contains no SQL parameters.
*/
int sqlite3_bind_parameter_count(sqlite3_stmt*);
/*
** CAPI3REF: Name Of A Host Parameter {H13620} <S70300>
**
** This routine returns a pointer to the name of the n-th
** [SQL parameter] in a [prepared statement].
** 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 also referred to as "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()] or
** [sqlite3_prepare16_v2()].
**
** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_count()], and
** [sqlite3_bind_parameter_index()].
**
** INVARIANTS:
**
** {H13621} The [sqlite3_bind_parameter_name(S,N)] interface returns
** a UTF-8 rendering of the name of the SQL parameter in
** the [prepared statement] S having index N, or
** NULL if there is no SQL parameter with index N or if the
** parameter with index N is an anonymous parameter "?".
*/
const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
/*
** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300>
**
** 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()].
**
** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_count()], and
** [sqlite3_bind_parameter_index()].
**
** INVARIANTS:
**
** {H13641} The [sqlite3_bind_parameter_index(S,N)] interface returns
** the index of SQL parameter in the [prepared statement]
** S whose name matches the UTF-8 string N, or 0 if there is
** no match.
*/
int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
/*
** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300>
**
** 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.
**
** INVARIANTS:
**
** {H13661} The [sqlite3_clear_bindings(S)] interface resets all SQL
** parameter bindings in the [prepared statement] S back to NULL.
*/
int sqlite3_clear_bindings(sqlite3_stmt*);
/*
** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700>
**
** Return the number of columns in the result set returned by the
** [prepared statement]. This routine returns 0 if pStmt is an SQL
** statement that does not return data (for example an [UPDATE]).
**
** INVARIANTS:
**
** {H13711} The [sqlite3_column_count(S)] interface returns the number of
** columns in the result set generated by the [prepared statement] S,
** or 0 if S does not generate a result set.
*/
int sqlite3_column_count(sqlite3_stmt *pStmt);
/*
** CAPI3REF: Column Names In A Result Set {H13720} <S10700>
**
** 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 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.
**
** INVARIANTS:
**
** {H13721} A successful invocation of the [sqlite3_column_name(S,N)]
** interface returns the name of the Nth column (where 0 is
** the leftmost column) for the result set of the
** [prepared statement] S as a zero-terminated UTF-8 string.
**
** {H13723} A successful invocation of the [sqlite3_column_name16(S,N)]
** interface returns the name of the Nth column (where 0 is
** the leftmost column) for the result set of the
** [prepared statement] S as a zero-terminated UTF-16 string
** in the native byte order.
**
** {H13724} The [sqlite3_column_name()] and [sqlite3_column_name16()]
** interfaces return a NULL pointer if they are unable to
** allocate memory to hold their normal return strings.
**
** {H13725} If the N parameter to [sqlite3_column_name(S,N)] or
** [sqlite3_column_name16(S,N)] is out of range, then the
** interfaces return a NULL pointer.
**
** {H13726} The strings returned by [sqlite3_column_name(S,N)] and
** [sqlite3_column_name16(S,N)] are valid until the next
** call to either routine with the same S and N parameters
** or until [sqlite3_finalize(S)] is called.
**
** {H13727} When a result column of a [SELECT] statement contains
** an AS clause, the name of that column is the identifier
** to the right of the AS keyword.
*/
const char *sqlite3_column_name(sqlite3_stmt*, int N);
const void *sqlite3_column_name16(sqlite3_stmt*, int N);
/*
** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700>
**
** These routines provide a means to determine what column of what
** table in which database a result of a [SELECT] statement comes from.
** 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 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 the following calls is a [prepared statement].
** These functions return information about the Nth column returned by
** the statement, where N is the second function argument.
**
** 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
** and column that query result column was extracted from.
**
** As with all other SQLite APIs, those postfixed with "16" return
** UTF-16 encoded strings, the other functions return UTF-8. {END}
**
** These APIs are only available if the library was compiled with the
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
**
** {A13751}
** 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.
**
** INVARIANTS:
**
** {H13741} The [sqlite3_column_database_name(S,N)] interface returns either
** the UTF-8 zero-terminated name of the database from which the
** Nth result column of the [prepared statement] S is extracted,
** or NULL if the Nth column of S is a general expression
** or if unable to allocate memory to store the name.
**
** {H13742} The [sqlite3_column_database_name16(S,N)] interface returns either
** the UTF-16 native byte order zero-terminated name of the database
** from which the Nth result column of the [prepared statement] S is
** extracted, or NULL if the Nth column of S is a general expression
** or if unable to allocate memory to store the name.
**
** {H13743} The [sqlite3_column_table_name(S,N)] interface returns either
** the UTF-8 zero-terminated name of the table from which the
** Nth result column of the [prepared statement] S is extracted,
** or NULL if the Nth column of S is a general expression
** or if unable to allocate memory to store the name.
**
** {H13744} The [sqlite3_column_table_name16(S,N)] interface returns either
** the UTF-16 native byte order zero-terminated name of the table
** from which the Nth result column of the [prepared statement] S is
** extracted, or NULL if the Nth column of S is a general expression
** or if unable to allocate memory to store the name.
**
** {H13745} The [sqlite3_column_origin_name(S,N)] interface returns either
** the UTF-8 zero-terminated name of the table column from which the
** Nth result column of the [prepared statement] S is extracted,
** or NULL if the Nth column of S is a general expression
** or if unable to allocate memory to store the name.
**
** {H13746} The [sqlite3_column_origin_name16(S,N)] interface returns either
** the UTF-16 native byte order zero-terminated name of the table
** column from which the Nth result column of the
** [prepared statement] S is extracted, or NULL if the Nth column
** of S is a general expression or if unable to allocate memory
** to store the name.
**
** {H13748} The return values from
** [sqlite3_column_database_name | column metadata interfaces]
** are valid for the lifetime of the [prepared statement]
** or until the encoding is changed by another metadata
** interface call for the same prepared statement and column.
**
** ASSUMPTIONS:
**
** {A13751} 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.
*/
const char *sqlite3_column_database_name(sqlite3_stmt*,int);
const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
const char *sqlite3_column_table_name(sqlite3_stmt*,int);
const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
/*
** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700>
**
** 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. {END}
**
** 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.
**
** INVARIANTS:
**
** {H13761} A successful call to [sqlite3_column_decltype(S,N)] returns a
** zero-terminated UTF-8 string containing the declared datatype
** of the table column that appears as the Nth column (numbered
** from 0) of the result set to the [prepared statement] S.
**
** {H13762} A successful call to [sqlite3_column_decltype16(S,N)]
** returns a zero-terminated UTF-16 native byte order string
** containing the declared datatype of the table column that appears
** as the Nth column (numbered from 0) of the result set to the
** [prepared statement] S.
**
** {H13763} If N is less than 0 or N is greater than or equal to
** the number of columns in the [prepared statement] S,
** or if the Nth column of S is an expression or subquery rather
** than a table column, or if a memory allocation failure
** occurs during encoding conversions, then
** calls to [sqlite3_column_decltype(S,N)] or
** [sqlite3_column_decltype16(S,N)] return NULL.
*/
const char *sqlite3_column_decltype(sqlite3_stmt*,int);
const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
/*
** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000>
**
** After a [prepared statement] has been prepared using either
** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] 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 "v2" interface
** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
** new "v2" 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 a
** 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.
**
** <b>Goofy Interface Alert:</b> 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 either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] 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 "v2" interface is recommended.
**
** INVARIANTS:
**
** {H13202} If the [prepared statement] S is ready to be run, then
** [sqlite3_step(S)] advances that prepared statement until
** completion or until it is ready to return another row of the
** result set, or until an [sqlite3_interrupt | interrupt]
** or a run-time error occurs.
**
** {H15304} When a call to [sqlite3_step(S)] causes the [prepared statement]
** S to run to completion, the function returns [SQLITE_DONE].
**
** {H15306} When a call to [sqlite3_step(S)] stops because it is ready to
** return another row of the result set, it returns [SQLITE_ROW].
**
** {H15308} If a call to [sqlite3_step(S)] encounters an
** [sqlite3_interrupt | interrupt] or a run-time error,
** it returns an appropriate error code that is not one of
** [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE].
**
** {H15310} If an [sqlite3_interrupt | interrupt] or a run-time error
** occurs during a call to [sqlite3_step(S)]
** for a [prepared statement] S created using
** legacy interfaces [sqlite3_prepare()] or
** [sqlite3_prepare16()], then the function returns either
** [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE].
*/
int sqlite3_step(sqlite3_stmt*);
/*
** CAPI3REF: Number of columns in a result set {H13770} <S10700>
**
** Returns the number of values in the current row of the result set.
**
** INVARIANTS:
**
** {H13771} After a call to [sqlite3_step(S)] that returns [SQLITE_ROW],
** the [sqlite3_data_count(S)] routine will return the same value
** as the [sqlite3_column_count(S)] function.
**
** {H13772} After [sqlite3_step(S)] has returned any value other than
** [SQLITE_ROW] or before [sqlite3_step(S)] has been called on the
** [prepared statement] for the first time since it was
** [sqlite3_prepare | prepared] or [sqlite3_reset | reset],
** the [sqlite3_data_count(S)] routine returns zero.
*/
int sqlite3_data_count(sqlite3_stmt *pStmt);
/*
** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120>
** KEYWORDS: SQLITE_TEXT
**
** {H10266} Every value in SQLite has one of five fundamental datatypes:
**
** <ul>
** <li> 64-bit signed integer
** <li> 64-bit IEEE floating point number
** <li> string
** <li> BLOB
** <li> NULL
** </ul> {END}
**
** 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 {H13800} <S10700>
** KEYWORDS: {column access functions}
**
** These routines form the "result set query" interface.
**
** 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.
**
** 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 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 value
** returned by sqlite3_column_type() is only meaningful if no type
** conversions have occurred as described below. After a type conversion,
** the value returned by sqlite3_column_type() is undefined. Future
** versions of SQLite may change the behavior of sqlite3_column_type()
** following a type conversion.
**
** 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.
** The value returned does not include the zero terminator at the end
** of the string. For clarity: the value returned is 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 an arbitrary
** pointer, possibly even a NULL pointer.
**
** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
** but leaves the result in UTF-16 in native byte order instead of UTF-8.
** The zero terminator is not included in this count.
**
** The object returned by [sqlite3_column_value()] is an
** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
** may only be used 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()], then the behavior is undefined.
**
** These routines attempt to convert the value where appropriate. 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:
**
** <blockquote>
** <table border="1">
** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
**
** <tr><td> NULL <td> INTEGER <td> Result is 0
** <tr><td> NULL <td> FLOAT <td> Result is 0.0
** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
** <tr><td> TEXT <td> INTEGER <td> Use atoi()
** <tr><td> TEXT <td> FLOAT <td> Use atof()
** <tr><td> TEXT <td> BLOB <td> No change
** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
** </table>
** </blockquote>
**
** The table above makes reference to standard C library functions atoi()
** and atof(). SQLite does not really use these functions. It has its
** own equivalent internal routines. The atoi() and atof() names are
** used in the table for brevity and because they are familiar to most
** C programmers.
**
** 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:
**
** <ul>
** <li> 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.</li>
** <li> 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.</li>
** <li> 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.</li>
** </ul>
**
** 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 points to 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 and easiest to remember policy is to invoke these routines
** in one of the following ways:
**
** <ul>
** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
** </ul>
**
** 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 <b>not</b> pass the pointers returned
** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
** [sqlite3_free()].
**
** If a memory allocation error occurs during the evaluation of any
** of these routines, a default value is returned. The default value
** is either the integer 0, the floating point number 0.0, or a NULL
** pointer. Subsequent calls to [sqlite3_errcode()] will return
** [SQLITE_NOMEM].
**
** INVARIANTS:
**
** {H13803} The [sqlite3_column_blob(S,N)] interface converts the
** Nth column in the current row of the result set for
** the [prepared statement] S into a BLOB and then returns a
** pointer to the converted value.
**
** {H13806} The [sqlite3_column_bytes(S,N)] interface returns the
** number of bytes in the BLOB or string (exclusive of the
** zero terminator on the string) that was returned by the
** most recent call to [sqlite3_column_blob(S,N)] or
** [sqlite3_column_text(S,N)].
**
** {H13809} The [sqlite3_column_bytes16(S,N)] interface returns the
** number of bytes in the string (exclusive of the
** zero terminator on the string) that was returned by the
** most recent call to [sqlite3_column_text16(S,N)].
**
** {H13812} The [sqlite3_column_double(S,N)] interface converts the
** Nth column in the current row of the result set for the
** [prepared statement] S into a floating point value and
** returns a copy of that value.
**
** {H13815} The [sqlite3_column_int(S,N)] interface converts the
** Nth column in the current row of the result set for the
** [prepared statement] S into a 64-bit signed integer and
** returns the lower 32 bits of that integer.
**
** {H13818} The [sqlite3_column_int64(S,N)] interface converts the
** Nth column in the current row of the result set for the
** [prepared statement] S into a 64-bit signed integer and
** returns a copy of that integer.
**
** {H13821} The [sqlite3_column_text(S,N)] interface converts the
** Nth column in the current row of the result set for
** the [prepared statement] S into a zero-terminated UTF-8
** string and returns a pointer to that string.
**
** {H13824} The [sqlite3_column_text16(S,N)] interface converts the
** Nth column in the current row of the result set for the
** [prepared statement] S into a zero-terminated 2-byte
** aligned UTF-16 native byte order string and returns
** a pointer to that string.
**
** {H13827} The [sqlite3_column_type(S,N)] interface returns
** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
** the Nth column in the current row of the result set for
** the [prepared statement] S.
**
** {H13830} The [sqlite3_column_value(S,N)] interface returns a
** pointer to an [unprotected sqlite3_value] object for the
** Nth column in the current row of the result set for
** the [prepared statement] S.
*/
const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
double sqlite3_column_double(sqlite3_stmt*, int iCol);
int sqlite3_column_int(sqlite3_stmt*, int iCol);
sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
int sqlite3_column_type(sqlite3_stmt*, int iCol);
sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
/*
** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100>
**
** The sqlite3_finalize() function is called to delete a [prepared statement].
** If the statement was executed successfully or not executed at all, then
** SQLITE_OK is returned. If execution of the statement failed then an
** [error code] or [extended error code] is returned.
**
** This routine can be called at any point during the execution of the
** [prepared statement]. If the virtual machine has not
** completed execution when this routine is called, that is like
** encountering an error or an [sqlite3_interrupt | interrupt].
** Incomplete updates may be rolled back and transactions canceled,
** depending on the circumstances, and the
** [error code] returned will be [SQLITE_ABORT].
**
** INVARIANTS:
**
** {H11302} The [sqlite3_finalize(S)] interface destroys the
** [prepared statement] S and releases all
** memory and file resources held by that object.
**
** {H11304} If the most recent call to [sqlite3_step(S)] for the
** [prepared statement] S returned an error,
** then [sqlite3_finalize(S)] returns that same error.
*/
int sqlite3_finalize(sqlite3_stmt *pStmt);
/*
** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300>
**
** 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.
**
** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
** back to the beginning of its program.
**
** {H11334} 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].
**
** {H11336} 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].
**
** {H11338} The [sqlite3_reset(S)] interface does not change the values
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
*/
int sqlite3_reset(sqlite3_stmt *pStmt);
/*
** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200>
** KEYWORDS: {function creation routines}
** KEYWORDS: {application-defined SQL function}
** KEYWORDS: {application-defined SQL functions}
**
** These two 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 difference between the
** two is that the second parameter, the name of the (scalar) function or
** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
** for sqlite3_create_function16().
**
** The first parameter is the [database connection] to which the SQL
** function is to be added. If a single program uses more than one database
** connection internally, then SQL functions must be added individually to
** each database connection.
**
** 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, exclusive of
** the zero-terminator. Note that the name length limit is in bytes, not
** characters. Any attempt to create a function with a longer name
** will result in [SQLITE_ERROR] being returned.
**
** The third parameter (nArg)
** is the number of arguments that the SQL function or
** aggregate takes. If this parameter is negative, then the SQL function or
** aggregate may take any number of arguments.
**
** The fourth parameter, eTextRep, specifies what
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
** its parameters. Any SQL function implementation should be able to work
** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
** more efficient with one encoding than another. It is allowed to
** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
** times with the same function but with different values of eTextRep.
** When multiple implementations of the same function are available, SQLite
** will pick the one that involves the least amount of data conversion.
** If there is only a single implementation which does not care what text
** encoding is used, then the fourth argument should be [SQLITE_ANY].
**
** The fifth parameter is an arbitrary pointer. The implementation of the
** function can gain access to this pointer using [sqlite3_user_data()].
**
** The seventh, eighth and ninth parameters, 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 should be passed as the xStep and xFinal
** parameters. An aggregate SQL function requires an implementation of xStep
** and xFinal and NULL should be passed for xFunc. To delete an existing
** SQL function or aggregate, pass NULL for all three function callbacks.
**
** 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 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.
** The first application-defined function with a given name overrides all
** built-in functions in the same [database connection] with the same name.
** Subsequent application-defined functions of the same name only override
** prior application-defined functions that are an exact match for the
** number of parameters and preferred encoding.
**
** 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.
**
** INVARIANTS:
**
** {H16103} The [sqlite3_create_function16(D,X,...)] interface shall behave
** as [sqlite3_create_function(D,X,...)] in every way except that it
** interprets the X argument as zero-terminated UTF-16
** native byte order instead of as zero-terminated UTF-8.
**
** {H16106} A successful invocation of the
** [sqlite3_create_function(D,X,N,E,...)] interface shall register
** or replaces callback functions in the [database connection] D
** used to implement the SQL function named X with N parameters
** and having a preferred text encoding of E.
**
** {H16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)]
** shall replace the P, F, S, and L values from any prior calls with
** the same D, X, N, and E values.
**
** {H16112} The [sqlite3_create_function(D,X,...)] interface shall fail
** if the SQL function name X is
** longer than 255 bytes exclusive of the zero terminator.
**
** {H16118} The [sqlite3_create_function(D,X,N,E,P,F,S,L)] interface
** shall fail unless either F is NULL and S and L are non-NULL or
*** F is non-NULL and S and L are NULL.
**
** {H16121} The [sqlite3_create_function(D,...)] interface shall fails with an
** error code of [SQLITE_BUSY] if there exist [prepared statements]
** associated with the [database connection] D.
**
** {H16124} The [sqlite3_create_function(D,X,N,...)] interface shall fail with
** an error code of [SQLITE_ERROR] if parameter N is less
** than -1 or greater than 127.
**
** {H16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)]
** interface shall register callbacks to be invoked for the
** SQL function
** named X when the number of arguments to the SQL function is
** exactly N.
**
** {H16130} When N is -1, the [sqlite3_create_function(D,X,N,...)]
** interface shall register callbacks to be invoked for the SQL
** function named X with any number of arguments.
**
** {H16133} When calls to [sqlite3_create_function(D,X,N,...)]
** specify multiple implementations of the same function X
** and when one implementation has N>=0 and the other has N=(-1)
** the implementation with a non-zero N shall be preferred.
**
** {H16136} When calls to [sqlite3_create_function(D,X,N,E,...)]
** specify multiple implementations of the same function X with
** the same number of arguments N but with different
** encodings E, then the implementation where E matches the
** database encoding shall preferred.
**
** {H16139} For an aggregate SQL function created using
** [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finalizer
** function L shall always be invoked exactly once if the
** step function S is called one or more times.
**
** {H16142} When SQLite invokes either the xFunc or xStep function of
** an application-defined SQL function or aggregate created
** by [sqlite3_create_function()] or [sqlite3_create_function16()],
** then the array of [sqlite3_value] objects passed as the
** third parameter shall be [protected sqlite3_value] objects.
*/
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*)
);
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*)
);
/*
** CAPI3REF: Text Encodings {H10267} <S50200> <H16100>
**
** These constant define integer codes that represent the various
** text encodings supported by SQLite.
*/
#define SQLITE_UTF8 1
#define SQLITE_UTF16LE 2
#define SQLITE_UTF16BE 3
#define SQLITE_UTF16 4 /* Use native byte order */
#define SQLITE_ANY 5 /* sqlite3_create_function only */
#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
/*
** 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 help encourage people to avoid
** using these functions, we are not going to tell you what they do.
*/
#ifndef SQLITE_OMIT_DEPRECATED
SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
SQLITE_DEPRECATED int sqlite3_global_recover(void);
SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
#endif
/*
** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
**
** The C-language implementation of SQL functions and aggregates uses
** this set of interface routines to access the parameter values on
** the function or aggregate.
**
** The xFunc (for scalar functions) or xStep (for aggregates) parameters
** to [sqlite3_create_function()] and [sqlite3_create_function16()]
** define callbacks that implement the SQL functions and aggregates.
** The 4th parameter to these callbacks is an array of pointers to
** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
** each parameter to the SQL function. These routines are used to
** extract values from the [sqlite3_value] objects.
**
** These routines work only with [protected sqlite3_value] objects.
** Any attempt to use these routines on an [unprotected sqlite3_value]
** object results in undefined behavior.
**
** 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.
**
** 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.
**
** 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.
**
** INVARIANTS:
**
** {H15103} The [sqlite3_value_blob(V)] interface converts the
** [protected sqlite3_value] object V into a BLOB and then
** returns a pointer to the converted value.
**
** {H15106} The [sqlite3_value_bytes(V)] interface returns the
** number of bytes in the BLOB or string (exclusive of the
** zero terminator on the string) that was returned by the
** most recent call to [sqlite3_value_blob(V)] or
** [sqlite3_value_text(V)].
**
** {H15109} The [sqlite3_value_bytes16(V)] interface returns the
** number of bytes in the string (exclusive of the
** zero terminator on the string) that was returned by the
** most recent call to [sqlite3_value_text16(V)],
** [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)].
**
** {H15112} The [sqlite3_value_double(V)] interface converts the
** [protected sqlite3_value] object V into a floating point value and
** returns a copy of that value.
**
** {H15115} The [sqlite3_value_int(V)] interface converts the
** [protected sqlite3_value] object V into a 64-bit signed integer and
** returns the lower 32 bits of that integer.
**
** {H15118} The [sqlite3_value_int64(V)] interface converts the
** [protected sqlite3_value] object V into a 64-bit signed integer and
** returns a copy of that integer.
**
** {H15121} The [sqlite3_value_text(V)] interface converts the
** [protected sqlite3_value] object V into a zero-terminated UTF-8
** string and returns a pointer to that string.
**
** {H15124} The [sqlite3_value_text16(V)] interface converts the
** [protected sqlite3_value] object V into a zero-terminated 2-byte
** aligned UTF-16 native byte order
** string and returns a pointer to that string.
**
** {H15127} The [sqlite3_value_text16be(V)] interface converts the
** [protected sqlite3_value] object V into a zero-terminated 2-byte
** aligned UTF-16 big-endian
** string and returns a pointer to that string.
**
** {H15130} The [sqlite3_value_text16le(V)] interface converts the
** [protected sqlite3_value] object V into a zero-terminated 2-byte
** aligned UTF-16 little-endian
** string and returns a pointer to that string.
**
** {H15133} The [sqlite3_value_type(V)] interface returns
** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
** the [sqlite3_value] object V.
**
** {H15136} The [sqlite3_value_numeric_type(V)] interface converts
** the [protected sqlite3_value] object V into either an integer or
** a floating point value if it can do so without loss of
** information, and returns one of [SQLITE_NULL],
** [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or
** [SQLITE_BLOB] as appropriate for the
** [protected sqlite3_value] object V after the conversion attempt.
*/
const void *sqlite3_value_blob(sqlite3_value*);
int sqlite3_value_bytes(sqlite3_value*);
int sqlite3_value_bytes16(sqlite3_value*);
double sqlite3_value_double(sqlite3_value*);
int sqlite3_value_int(sqlite3_value*);
sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
const unsigned char *sqlite3_value_text(sqlite3_value*);
const void *sqlite3_value_text16(sqlite3_value*);
const void *sqlite3_value_text16le(sqlite3_value*);
const void *sqlite3_value_text16be(sqlite3_value*);
int sqlite3_value_type(sqlite3_value*);
int sqlite3_value_numeric_type(sqlite3_value*);
/*
** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200>
**
** The implementation of aggregate SQL functions use this routine to allocate
** a structure for storing their state.
**
** The first time the sqlite3_aggregate_context() routine is called for a
** particular aggregate, SQLite allocates nBytes of memory, zeroes out that
** memory, and returns a pointer to it. On second and subsequent calls to
** sqlite3_aggregate_context() for the same aggregate function index,
** the same buffer is returned. The implementation of the aggregate can use
** the returned buffer to accumulate data.
**
** SQLite automatically frees the allocated buffer when the aggregate
** query concludes.
**
** The first parameter should be a copy of the
** [sqlite3_context | SQL function context] that is the first parameter
** to the callback routine that implements the aggregate function.
**
** This routine must be called from the same thread in which
** the aggregate SQL function is running.
**
** INVARIANTS:
**
** {H16211} The first invocation of [sqlite3_aggregate_context(C,N)] for
** a particular instance of an aggregate function (for a particular
** context C) causes SQLite to allocate N bytes of memory,
** zero that memory, and return a pointer to the allocated memory.
**
** {H16213} If a memory allocation error occurs during
** [sqlite3_aggregate_context(C,N)] then the function returns 0.
**
** {H16215} Second and subsequent invocations of
** [sqlite3_aggregate_context(C,N)] for the same context pointer C
** ignore the N parameter and return a pointer to the same
** block of memory returned by the first invocation.
**
** {H16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is
** automatically freed on the next call to [sqlite3_reset()]
** or [sqlite3_finalize()] for the [prepared statement] containing
** the aggregate function associated with context C.
*/
void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
/*
** CAPI3REF: User Data For Functions {H16240} <S20200>
**
** 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. {END}
**
** This routine must be called from the same thread in which
** the application-defined function is running.
**
** INVARIANTS:
**
** {H16243} The [sqlite3_user_data(C)] interface returns a copy of the
** P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
** registered the SQL function associated with [sqlite3_context] C.
*/
void *sqlite3_user_data(sqlite3_context*);
/*
** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200>
**
** 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.
**
** INVARIANTS:
**
** {H16253} The [sqlite3_context_db_handle(C)] interface returns a copy of the
** D pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
** registered the SQL function associated with [sqlite3_context] C.
*/
sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
/*
** CAPI3REF: Function Auxiliary Data {H16270} <S20200>
**
** The following two functions may be used by scalar 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. This may
** be used, for example, to add a regular-expression matching scalar
** function. The compiled version of the regular expression is stored as
** metadata associated with the SQL value passed as the regular expression
** pattern. The compiled regular expression can be reused on multiple
** invocations of the same function so that the original pattern string
** does not need to be recompiled on each invocation.
**
** The sqlite3_get_auxdata() interface returns a pointer to the metadata
** associated by the sqlite3_set_auxdata() function with the Nth argument
** value to the application-defined function. If no metadata has been ever
** been set for the Nth argument of the function, or if the corresponding
** function parameter has changed since the meta-data was set,
** then sqlite3_get_auxdata() returns a NULL pointer.
**
** The sqlite3_set_auxdata() interface saves the metadata
** pointed to by its 3rd parameter as the metadata for the N-th
** argument of the application-defined function. Subsequent
** calls to sqlite3_get_auxdata() might return this data, if it has
** not been destroyed.
** If it is not NULL, SQLite will invoke the destructor
** function given by the 4th parameter to sqlite3_set_auxdata() on
** the metadata when the corresponding function parameter changes
** or when the SQL statement completes, whichever comes first.
**
** SQLite is free to call the destructor and drop metadata on any
** parameter of any function at any time. The only guarantee is that
** the destructor will be called before the metadata is dropped.
**
** In practice, metadata is preserved between function calls for
** expressions that are constant at compile time. This includes literal
** values and SQL variables.
**
** These routines must be called from the same thread in which
** the SQL function is running.
**
** INVARIANTS:
**
** {H16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer
** to metadata associated with the Nth parameter of the SQL function
** whose context is C, or NULL if there is no metadata associated
** with that parameter.
**
** {H16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata
** pointer P to the Nth parameter of the SQL function with context C.
**
** {H16276} SQLite will invoke the destructor D with a single argument
** which is the metadata pointer P following a call to
** [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold
** the metadata.
**
** {H16277} SQLite ceases to hold metadata for an SQL function parameter
** when the value of that parameter changes.
**
** {H16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor
** is called for any prior metadata associated with the same function
** context C and parameter N.
**
** {H16279} SQLite will call destructors for any metadata it is holding
** in a particular [prepared statement] S when either
** [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called.
*/
void *sqlite3_get_auxdata(sqlite3_context*, int N);
void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
/*
** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100>
**
** 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. See ticket #2191.
*/
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 {H16400} <S20200>
**
** 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() interfaces set the result of
** the application-defined function to be a BLOB containing all zero
** bytes and N bytes in size, where N is the value of the 2nd parameter.
**
** 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_toobig() interface causes SQLite to throw an error
** indicating that a string or BLOB is to long to represent.
**
** The sqlite3_result_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.
** 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 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
** 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 it or call a destructor 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
** from [sqlite3_malloc()] before it returns.
**
** The sqlite3_result_value() interface sets the result of
** the application-defined function to be a copy 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.
**
** 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.
**
** INVARIANTS:
**
** {H16403} The default return value from any SQL function is NULL.
**
** {H16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the
** return value of function C to be a BLOB that is N bytes
** in length and with content pointed to by V.
**
** {H16409} The [sqlite3_result_double(C,V)] interface changes the
** return value of function C to be the floating point value V.
**
** {H16412} The [sqlite3_result_error(C,V,N)] interface changes the return
** value of function C to be an exception with error code
** [SQLITE_ERROR] and a UTF-8 error message copied from V up to the
** first zero byte or until N bytes are read if N is positive.
**
** {H16415} The [sqlite3_result_error16(C,V,N)] interface changes the return
** value of function C to be an exception with error code
** [SQLITE_ERROR] and a UTF-16 native byte order error message
** copied from V up to the first zero terminator or until N bytes
** are read if N is positive.
**
** {H16418} The [sqlite3_result_error_toobig(C)] interface changes the return
** value of the function C to be an exception with error code
** [SQLITE_TOOBIG] and an appropriate error message.
**
** {H16421} The [sqlite3_result_error_nomem(C)] interface changes the return
** value of the function C to be an exception with error code
** [SQLITE_NOMEM] and an appropriate error message.
**
** {H16424} The [sqlite3_result_error_code(C,E)] interface changes the return
** value of the function C to be an exception with error code E.
** The error message text is unchanged.
**
** {H16427} The [sqlite3_result_int(C,V)] interface changes the
** return value of function C to be the 32-bit integer value V.
**
** {H16430} The [sqlite3_result_int64(C,V)] interface changes the
** return value of function C to be the 64-bit integer value V.
**
** {H16433} The [sqlite3_result_null(C)] interface changes the
** return value of function C to be NULL.
**
** {H16436} The [sqlite3_result_text(C,V,N,D)] interface changes the
** return value of function C to be the UTF-8 string
** V up to the first zero if N is negative
** or the first N bytes of V if N is non-negative.
**
** {H16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the
** return value of function C to be the UTF-16 native byte order
** string V up to the first zero if N is negative
** or the first N bytes of V if N is non-negative.
**
** {H16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the
** return value of function C to be the UTF-16 big-endian
** string V up to the first zero if N is negative
** or the first N bytes or V if N is non-negative.
**
** {H16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the
** return value of function C to be the UTF-16 little-endian
** string V up to the first zero if N is negative
** or the first N bytes of V if N is non-negative.
**
** {H16448} The [sqlite3_result_value(C,V)] interface changes the
** return value of function C to be the [unprotected sqlite3_value]
** object V.
**
** {H16451} The [sqlite3_result_zeroblob(C,N)] interface changes the
** return value of function C to be an N-byte BLOB of all zeros.
**
** {H16454} The [sqlite3_result_error()] and [sqlite3_result_error16()]
** interfaces make a copy of their error message strings before
** returning.
**
** {H16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
** [sqlite3_result_text16be(C,V,N,D)], or
** [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC]
** then no destructor is ever called on the pointer V and SQLite
** assumes that V is immutable.
**
** {H16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
** [sqlite3_result_text16be(C,V,N,D)], or
** [sqlite3_result_text16le(C,V,N,D)] is the constant
** [SQLITE_TRANSIENT] then the interfaces makes a copy of the
** content of V and retains the copy.
**
** {H16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
** [sqlite3_result_text16be(C,V,N,D)], or
** [sqlite3_result_text16le(C,V,N,D)] is some value other than
** the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then
** SQLite will invoke the destructor D with V as its only argument
** when it has finished with the V value.
*/
void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
void sqlite3_result_double(sqlite3_context*, double);
void sqlite3_result_error(sqlite3_context*, const char*, int);
void sqlite3_result_error16(sqlite3_context*, const void*, int);
void sqlite3_result_error_toobig(sqlite3_context*);
void sqlite3_result_error_nomem(sqlite3_context*);
void sqlite3_result_error_code(sqlite3_context*, int);
void sqlite3_result_int(sqlite3_context*, int);
void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
void sqlite3_result_null(sqlite3_context*);
void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
void sqlite3_result_zeroblob(sqlite3_context*, int n);
/*
** CAPI3REF: Define New Collating Sequences {H16600} <S20300>
**
** These functions are used to add new collation sequences to the
** [database connection] specified as the first argument.
**
** The name of the new collation sequence is specified as a UTF-8 string
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
** and a UTF-16 string for sqlite3_create_collation16(). In all cases
** the name is passed as the second function argument.
**
** The third argument may be one of the constants [SQLITE_UTF8],
** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
** routine expects to be passed pointers to strings encoded using UTF-8,
** UTF-16 little-endian, or UTF-16 big-endian, respectively. The
** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that
** the routine expects pointers to 16-bit word aligned strings
** of UTF-16 in the native byte order of the host computer.
**
** A pointer to the user supplied routine must be passed as the fifth
** argument. If it is NULL, this is the same as deleting the collation
** sequence (so that SQLite cannot call it anymore).
** Each time the application supplied function is invoked, it is passed
** as its first parameter a copy of the void* passed as the fourth argument
** to sqlite3_create_collation() or sqlite3_create_collation16().
**
** The remaining arguments to the application-supplied routine are two strings,
** each represented by a (length, data) pair and encoded in the encoding
** that was passed as the third argument when the collation sequence was
** registered. {END} The application defined collation routine should
** return negative, zero or positive if the first string is less than,
** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
**
** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
** except that it takes an extra argument which is a destructor for
** the collation. The destructor is called when the collation is
** destroyed and is passed a copy of the fourth parameter void* pointer
** of the sqlite3_create_collation_v2().
** Collations are destroyed when they are overridden by later calls to the
** collation creation functions or when the [database connection] is closed
** using [sqlite3_close()].
**
** INVARIANTS:
**
** {H16603} A successful call to the
** [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface
** registers function F as the comparison function used to
** implement collation X on the [database connection] B for
** databases having encoding E.
**
** {H16604} SQLite understands the X parameter to
** [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated
** UTF-8 string in which case is ignored for ASCII characters and
** is significant for non-ASCII characters.
**
** {H16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)]
** with the same values for B, X, and E, override prior values
** of P, F, and D.
**
** {H16609} If the destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
** is not NULL then it is called with argument P when the
** collating function is dropped by SQLite.
**
** {H16612} A collating function is dropped when it is overloaded.
**
** {H16615} A collating function is dropped when the database connection
** is closed using [sqlite3_close()].
**
** {H16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
** is passed through as the first parameter to the comparison
** function F for all subsequent invocations of F.
**
** {H16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly
** the same as a call to [sqlite3_create_collation_v2()] with
** the same parameters and a NULL destructor.
**
** {H16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)],
** SQLite uses the comparison function F for all text comparison
** operations on the [database connection] B on text values that
** use the collating sequence named X.
**
** {H16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same
** as [sqlite3_create_collation(B,X,E,P,F)] except that the
** collation name X is understood as UTF-16 in native byte order
** instead of UTF-8.
**
** {H16630} When multiple comparison functions are available for the same
** collating sequence, SQLite chooses the one whose text encoding
** requires the least amount of conversion from the default
** text encoding of the database.
*/
int sqlite3_create_collation(
sqlite3*,
const char *zName,
int eTextRep,
void*,
int(*xCompare)(void*,int,const void*,int,const void*)
);
int sqlite3_create_collation_v2(
sqlite3*,
const char *zName,
int eTextRep,
void*,
int(*xCompare)(void*,int,const void*,int,const void*),
void(*xDestroy)(void*)
);
int sqlite3_create_collation16(
sqlite3*,
const void *zName,
int eTextRep,
void*,
int(*xCompare)(void*,int,const void*,int,const void*)
);
/*
** CAPI3REF: Collation Needed Callbacks {H16700} <S20300>
**
** 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 called 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. {H16703} If sqlite3_collation_needed16() is used,
** the names are passed as UTF-16 in machine native byte order.
** A call to either function replaces any existing 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()].
**
** INVARIANTS:
**
** {H16702} A successful call to [sqlite3_collation_needed(D,P,F)]
** or [sqlite3_collation_needed16(D,P,F)] causes
** the [database connection] D to invoke callback F with first
** parameter P whenever it needs a comparison function for a
** collating sequence that it does not know about.
**
** {H16704} Each successful call to [sqlite3_collation_needed()] or
** [sqlite3_collation_needed16()] overrides the callback registered
** on the same [database connection] by prior calls to either
** interface.
**
** {H16706} The name of the requested collating function passed in the
** 4th parameter to the callback is in UTF-8 if the callback
** was registered using [sqlite3_collation_needed()] and
** is in UTF-16 native byte order if the callback was
** registered using [sqlite3_collation_needed16()].
*/
int sqlite3_collation_needed(
sqlite3*,
void*,
void(*)(void*,sqlite3*,int eTextRep,const char*)
);
int sqlite3_collation_needed16(
sqlite3*,
void*,
void(*)(void*,sqlite3*,int eTextRep,const void*)
);
/*
** 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.
*/
int sqlite3_key(
sqlite3 *db, /* Database to be rekeyed */
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.
*/
int sqlite3_rekey(
sqlite3 *db, /* Database to be rekeyed */
const void *pKey, int nKey /* The new key */
);
/*
** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410>
**
** 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.
**
** INVARIANTS:
**
** {H10533} The [sqlite3_sleep(M)] interface invokes the xSleep
** method of the default [sqlite3_vfs|VFS] in order to
** suspend execution of the current thread for at least
** M milliseconds.
**
** {H10536} The [sqlite3_sleep(M)] interface returns the number of
** milliseconds of sleep actually requested of the operating
** system, which might be larger than the parameter M.
*/
int sqlite3_sleep(int);
/*
** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000>
**
** 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 will be placed in that directory. If this variable
** is a NULL pointer, then SQLite performs a search for an appropriate
** temporary file directory.
**
** It is not safe to modify this variable once a [database connection]
** has been opened. It is intended that this variable be set once
** as part of process initialization and before any SQLite interface
** routines have been call and remain unchanged thereafter.
*/
SQLITE_EXTERN char *sqlite3_temp_directory;
/*
** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200>
** KEYWORDS: {autocommit mode}
**
** 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.
**
** INVARIANTS:
**
** {H12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or
** zero if the [database connection] D is or is not in autocommit
** mode, respectively.
**
** {H12932} Autocommit mode is on by default.
**
** {H12933} Autocommit mode is disabled by a successful [BEGIN] statement.
**
** {H12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK]
** statement.
**
** ASSUMPTIONS:
**
** {A12936} If another thread changes the autocommit status of the database
** connection while this routine is running, then the return value
** is undefined.
*/
int sqlite3_get_autocommit(sqlite3*);
/*
** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600>
**
** The sqlite3_db_handle interface returns the [database connection] handle
** to which a [prepared statement] belongs. The database handle returned by
** sqlite3_db_handle is the same database handle 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.
**
** INVARIANTS:
**
** {H13123} The [sqlite3_db_handle(S)] interface returns a pointer
** to the [database connection] associated with the
** [prepared statement] S.
*/
sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
/*
** CAPI3REF: Find the next prepared statement {H13140} <S60600>
**
** 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.
**
** INVARIANTS:
**
** {H13143} If D is a [database connection] that holds one or more
** unfinalized [prepared statements] and S is a NULL pointer,
** then [sqlite3_next_stmt(D, S)] routine shall return a pointer
** to one of the prepared statements associated with D.
**
** {H13146} If D is a [database connection] that holds no unfinalized
** [prepared statements] and S is a NULL pointer, then
** [sqlite3_next_stmt(D, S)] routine shall return a NULL pointer.
**
** {H13149} If S is a [prepared statement] in the [database connection] D
** and S is not the last prepared statement in D, then
** [sqlite3_next_stmt(D, S)] routine shall return a pointer
** to the next prepared statement in D after S.
**
** {H13152} If S is the last [prepared statement] in the
** [database connection] D then the [sqlite3_next_stmt(D, S)]
** routine shall return a NULL pointer.
**
** ASSUMPTIONS:
**
** {A13154} 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.
*/
sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
/*
** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400>
**
** The sqlite3_commit_hook() interface registers a callback
** function to be invoked whenever a transaction is 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 committed.
** Any callback set by a previous call to sqlite3_commit_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.
**
** If another function was previously registered, its
** pArg value is returned. Otherwise NULL is returned.
**
** 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 [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
** database connections for the meaning of "modify" in this paragraph.
**
** Registering a NULL function disables the callback.
**
** 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.
** The rollback callback is not invoked if a transaction is
** rolled back because a commit callback returned non-zero.
** <todo> Check on this </todo>
**
** INVARIANTS:
**
** {H12951} The [sqlite3_commit_hook(D,F,P)] interface registers the
** callback function F to be invoked with argument P whenever
** a transaction commits on the [database connection] D.
**
** {H12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P argument
** from the previous call with the same [database connection] D,
** or NULL on the first call for a particular database connection D.
**
** {H12953} Each call to [sqlite3_commit_hook()] overwrites the callback
** registered by prior calls.
**
** {H12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL
** then the commit hook callback is canceled and no callback
** is invoked when a transaction commits.
**
** {H12955} If the commit callback returns non-zero then the commit is
** converted into a rollback.
**
** {H12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the
** callback function F to be invoked with argument P whenever
** a transaction rolls back on the [database connection] D.
**
** {H12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P
** argument from the previous call with the same
** [database connection] D, or NULL on the first call
** for a particular database connection D.
**
** {H12963} Each call to [sqlite3_rollback_hook()] overwrites the callback
** registered by prior calls.
**
** {H12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL
** then the rollback hook callback is canceled and no callback
** is invoked when a transaction rolls back.
*/
void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
/*
** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400>
**
** 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.
** 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.
** 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 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.
**
** If another function was previously registered, its pArg value
** is returned. Otherwise NULL is returned.
**
** INVARIANTS:
**
** {H12971} The [sqlite3_update_hook(D,F,P)] interface causes the callback
** function F to be invoked with first parameter P whenever
** a table row is modified, inserted, or deleted on
** the [database connection] D.
**
** {H12973} The [sqlite3_update_hook(D,F,P)] interface returns the value
** of P for the previous call on the same [database connection] D,
** or NULL for the first call.
**
** {H12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)]
** is NULL then the no update callbacks are made.
**
** {H12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls
** to the same interface on the same [database connection] D.
**
** {H12979} The update hook callback is not invoked when internal system
** tables such as sqlite_master and sqlite_sequence are modified.
**
** {H12981} The second parameter to the update callback
** is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
** depending on the operation that caused the callback to be invoked.
**
** {H12983} The third and fourth arguments to the callback contain pointers
** to zero-terminated UTF-8 strings which are the names of the
** database and table that is being updated.
** {H12985} The final callback parameter is the [rowid] of the row after
** the change occurs.
*/
void *sqlite3_update_hook(
sqlite3*,
void(*)(void *,int ,char const *,char const *,sqlite3_int64),
void*
);
/*
** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900>
** KEYWORDS: {shared cache} {shared cache mode}
**
** 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. {END}
** This is a change as of SQLite version 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.
**
** Virtual tables cannot be used with a shared cache. When shared
** cache is enabled, the [sqlite3_create_module()] API used to register
** virtual tables will always return an error.
**
** 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.
**
** INVARIANTS:
**
** {H10331} A successful invocation of [sqlite3_enable_shared_cache(B)]
** will enable or disable shared cache mode for any subsequently
** created [database connection] in the same process.
**
** {H10336} When shared cache is enabled, the [sqlite3_create_module()]
** interface will always return an error.
**
** {H10337} The [sqlite3_enable_shared_cache(B)] interface returns
** [SQLITE_OK] if shared cache was enabled or disabled successfully.
**
** {H10339} Shared cache is disabled by default.
*/
int sqlite3_enable_shared_cache(int);
/*
** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220>
**
** The sqlite3_release_memory() interface attempts to free N bytes
** of heap memory by deallocating non-essential memory allocations
** held by the database library. {END} 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.
**
** INVARIANTS:
**
** {H17341} The [sqlite3_release_memory(N)] interface attempts to
** free N bytes of heap memory by deallocating non-essential
** memory allocations held by the database library.
**
** {H16342} The [sqlite3_release_memory(N)] returns the number
** of bytes actually freed, which might be more or less
** than the amount requested.
*/
int sqlite3_release_memory(int);
/*
** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220>
**
** The sqlite3_soft_heap_limit() interface places a "soft" limit
** on the amount of heap memory that may be allocated by SQLite.
** If an internal allocation is requested that would exceed the
** soft heap limit, [sqlite3_release_memory()] is invoked one or
** more times to free up some space before the allocation is performed.
**
** The limit is called "soft", because if [sqlite3_release_memory()]
** cannot free sufficient memory to prevent the limit from being exceeded,
** the memory is allocated anyway and the current operation proceeds.
**
** A negative or zero value for N means that there is no soft heap limit and
** [sqlite3_release_memory()] will only be called when memory is exhausted.
** The default value for the soft heap limit is zero.
**
** SQLite makes a best effort to honor the soft heap limit.
** But if the soft heap limit cannot be honored, execution will
** continue without error or notification. This is why the limit is
** called a "soft" limit. It is advisory only.
**
** Prior to SQLite version 3.5.0, this routine only constrained the memory
** allocated by a single thread - the same thread in which this routine
** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
** applied to all threads. The value specified for the soft heap limit
** is an upper bound on the total memory allocation for all threads. In
** version 3.5.0 there is no mechanism for limiting the heap usage for
** individual threads.
**
** INVARIANTS:
**
** {H16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit
** of N bytes on the amount of heap memory that may be allocated
** using [sqlite3_malloc()] or [sqlite3_realloc()] at any point
** in time.
**
** {H16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would
** cause the total amount of allocated memory to exceed the
** soft heap limit, then [sqlite3_release_memory()] is invoked
** in an attempt to reduce the memory usage prior to proceeding
** with the memory allocation attempt.
**
** {H16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger
** attempts to reduce memory usage through the soft heap limit
** mechanism continue even if the attempt to reduce memory
** usage is unsuccessful.
**
** {H16354} A negative or zero value for N in a call to
** [sqlite3_soft_heap_limit(N)] means that there is no soft
** heap limit and [sqlite3_release_memory()] will only be
** called when memory is completely exhausted.
**
** {H16355} The default value for the soft heap limit is zero.
**
** {H16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the
** values set by all prior calls.
*/
void sqlite3_soft_heap_limit(int);
/*
** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300>
**
** This routine returns metadata about a specific column of a specific
** database table accessible using the [database connection] handle
** passed as the first function argument.
**
** 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. Neither of these parameters
** may be NULL.
**
** 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.
**
** <blockquote>
** <table border="1">
** <tr><th> Parameter <th> Output<br>Type <th> Description
**
** <tr><td> 5th <td> const char* <td> Data type
** <tr><td> 6th <td> const char* <td> Name of default collation sequence
** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
** </table>
** </blockquote>
**
** The memory pointed to by the character pointers returned for the
** declaration type and collation sequence is valid only 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 an
** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
** parameters are set for the explicitly declared column. If there is no
** explicitly declared [INTEGER PRIMARY KEY] column, then the output
** parameters are set as follows:
**
** <pre>
** data type: "INTEGER"
** collation sequence: "BINARY"
** not null: 0
** primary key: 1
** auto increment: 0
** </pre>
**
** This function may load one or more schemas from database files. If an
** error occurs during this process, or if the requested table or column
** cannot be found, an [error code] is returned and an error message left
** in the [database connection] (to be retrieved using sqlite3_errmsg()).
**
** This API is only available if the library was compiled with the
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
*/
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 {H12600} <S20500>
**
** This interface loads an SQLite extension library from the named file.
**
** {H12601} The sqlite3_load_extension() interface attempts to load an
** SQLite extension library contained in the file zFile.
**
** {H12602} The entry point is zProc.
**
** {H12603} zProc may be 0, in which case the name of the entry point
** defaults to "sqlite3_extension_init".
**
** {H12604} The sqlite3_load_extension() interface shall return
** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
**
** {H12605} 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()]. {END} The calling function
** should free this memory by calling [sqlite3_free()].
**
** {H12606} Extension loading must be enabled using
** [sqlite3_enable_load_extension()] prior to calling this API,
** otherwise an error will be returned.
*/
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 {H12620} <S20500>
**
** 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. See ticket #1863.
**
** {H12621} 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.
**
** {H12622} Extension loading is off by default.
*/
int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
/*
** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
**
** This API can be invoked at program startup in order to register
** one or more statically linked extensions that will be available
** to all new [database connections]. {END}
**
** This routine stores a pointer to the extension in an array that is
** obtained from [sqlite3_malloc()]. If you run a memory leak checker
** on your program and it reports a leak because of this array, invoke
** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
**
** {H12641} This function registers an extension entry point that is
** automatically invoked whenever a new [database connection]
** is opened using [sqlite3_open()], [sqlite3_open16()],
** or [sqlite3_open_v2()].
**
** {H12642} Duplicate extensions are detected so calling this routine
** multiple times with the same extension is harmless.
**
** {H12643} This routine stores a pointer to the extension in an array
** that is obtained from [sqlite3_malloc()].
**
** {H12644} Automatic extensions apply across all threads.
*/
int sqlite3_auto_extension(void (*xEntryPoint)(void));
/*
** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
**
** This function disables all previously registered automatic
** extensions. {END} It undoes the effect of all prior
** [sqlite3_auto_extension()] calls.
**
** {H12661} This function disables all previously registered
** automatic extensions.
**
** {H12662} This function disables automatic extensions in all threads.
*/
void sqlite3_reset_auto_extension(void);
/*
****** EXPERIMENTAL - subject to change without notice **************
**
** 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 {H18000} <S20400>
** KEYWORDS: sqlite3_module
** EXPERIMENTAL
**
** A module is a class of virtual tables. Each module is defined
** by an instance of the following structure. This structure consists
** mostly of methods for the module.
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
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);
};
/*
** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400>
** KEYWORDS: sqlite3_index_info
** EXPERIMENTAL
**
** The sqlite3_index_info structure and its substructures is used to
** pass information into and receive the reply from the xBestIndex
** method of an sqlite3_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:
**
** <pre>column OP expr</pre>
**
** where OP is =, &lt;, &lt;=, &gt;, or &gt;=. The particular operator is
** stored in aConstraint[].op. 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 in the correct
** form that refer 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 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 xFilter.
** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
**
** The orderByConsumed means that output from xFilter 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 doing the
** particular lookup. A full scan of a table with N entries should have
** a cost of N. A binary search of a table of N entries should have a
** cost of approximately log(N).
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
struct sqlite3_index_info {
/* Inputs */
int nConstraint; /* Number of entries in aConstraint */
struct sqlite3_index_constraint {
int iColumn; /* Column on left-hand side of constraint */
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 */
};
#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
/*
** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400>
** EXPERIMENTAL
**
** This routine is used to register a new module name with a
** [database connection]. Module names must be registered before
** creating new virtual tables on the module, or before using
** preexisting virtual tables of the module.
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
SQLITE_EXPERIMENTAL int sqlite3_create_module(
sqlite3 *db, /* SQLite connection to register module with */
const char *zName, /* Name of the module */
const sqlite3_module *, /* Methods for the module */
void * /* Client data for xCreate/xConnect */
);
/*
** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
** EXPERIMENTAL
**
** This routine is identical to the [sqlite3_create_module()] method above,
** except that it allows a destructor function to be specified. It is
** even more experimental than the rest of the virtual tables API.
*/
SQLITE_EXPERIMENTAL int sqlite3_create_module_v2(
sqlite3 *db, /* SQLite connection to register module with */
const char *zName, /* Name of the module */
const sqlite3_module *, /* Methods for the module */
void *, /* Client data for xCreate/xConnect */
void(*xDestroy)(void*) /* Module destructor function */
);
/*
** CAPI3REF: Virtual Table Instance Object {H18010} <S20400>
** KEYWORDS: sqlite3_vtab
** EXPERIMENTAL
**
** Every module implementation uses a subclass of the following structure
** to describe a particular instance of the module. 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. Note
** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
** since virtual tables are commonly implemented in loadable extensions which
** do not have access to sqlite3MPrintf() or sqlite3Free().
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
struct sqlite3_vtab {
const sqlite3_module *pModule; /* The module for this virtual table */
int nRef; /* Used internally */
char *zErrMsg; /* Error message from sqlite3_mprintf() */
/* Virtual table implementations will typically add additional fields */
};
/*
** CAPI3REF: Virtual Table Cursor Object {H18020} <S20400>
** KEYWORDS: sqlite3_vtab_cursor
** EXPERIMENTAL
**
** Every 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
** xOpen method 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.
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
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 {H18280} <S20400>
** EXPERIMENTAL
**
** The xCreate and xConnect methods of a module use the following API
** to declare the format (the names and datatypes of the columns) of
** the virtual tables they implement.
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
SQLITE_EXPERIMENTAL int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
/*
** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
** EXPERIMENTAL
**
** Virtual tables can provide alternative implementations of functions
** using the xFindFunction method. 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 virtual tables.
**
** This API should be considered part of the virtual table interface,
** which is experimental and subject to change.
*/
SQLITE_EXPERIMENTAL 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.
**
****** EXPERIMENTAL - subject to change without notice **************
*/
/*
** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230>
** 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 {H17810} <S30230>
**
** 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:
**
** <pre>
** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
** </pre> {END}
**
** If the flags parameter is non-zero, the the BLOB is opened for read
** and write access. If it is zero, the BLOB is opened for read access.
**
** Note that the database name is not the filename that contains
** the database but rather the symbolic name of the database that
** is assigned when the database is connected using [ATTACH].
** For the main database file, the database name is "main".
** For TEMP tables, the database name is "temp".
**
** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
** to *ppBlob. Otherwise an [error code] is returned and any value written
** to *ppBlob should not be used by the caller.
** This function sets the [database connection] error code and message
** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
**
** 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
** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
** Changes written into a BLOB prior to the BLOB expiring are not
** rollback by the expiration of the BLOB. Such changes will eventually
** commit if the transaction continues to completion.
**
** INVARIANTS:
**
** {H17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
** interface shall open an [sqlite3_blob] object P on the BLOB
** in column C of the table T in the database B on
** the [database connection] D.
**
** {H17814} A successful invocation of [sqlite3_blob_open(D,...)] shall start
** a new transaction on the [database connection] D if that
** connection is not already in a transaction.
**
** {H17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface shall open
** the BLOB for read and write access if and only if the F
** parameter is non-zero.
**
** {H17819} The [sqlite3_blob_open()] interface shall return [SQLITE_OK] on
** success and an appropriate [error code] on failure.
**
** {H17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
** then subsequent calls to [sqlite3_errcode(D)],
** [sqlite3_extended_errcode()],
** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
** information appropriate for that error.
**
** {H17824} If any column in the row that a [sqlite3_blob] has open is
** changed by a separate [UPDATE] or [DELETE] statement or by
** an [ON CONFLICT] side effect, then the [sqlite3_blob] shall
** be marked as invalid.
*/
int sqlite3_blob_open(
sqlite3*,
const char *zDb,
const char *zTable,
const char *zColumn,
sqlite3_int64 iRow,
int flags,
sqlite3_blob **ppBlob
);
/*
** CAPI3REF: Close A BLOB Handle {H17830} <S30230>
**
** Closes an open [BLOB handle].
**
** Closing a BLOB shall cause the current transaction to commit
** if there are no other BLOBs, no pending prepared statements, and the
** database connection is in [autocommit mode].
** If any writes were made to the BLOB, they might be held in cache
** until the close operation if they will fit. {END}
**
** Closing the BLOB often forces the changes
** out to disk and so if any I/O errors occur, they will likely occur
** at the time when the BLOB is closed. {H17833} Any errors that occur during
** closing are reported as a non-zero return value.
**
** The BLOB is closed unconditionally. Even if this routine returns
** an error code, the BLOB is still closed.
**
** INVARIANTS:
**
** {H17833} The [sqlite3_blob_close(P)] interface closes an [sqlite3_blob]
** object P previously opened using [sqlite3_blob_open()].
**
** {H17836} Closing an [sqlite3_blob] object using
** [sqlite3_blob_close()] shall cause the current transaction to
** commit if there are no other open [sqlite3_blob] objects
** or [prepared statements] on the same [database connection] and
** the database connection is in [autocommit mode].
**
** {H17839} The [sqlite3_blob_close(P)] interfaces shall close the
** [sqlite3_blob] object P unconditionally, even if
** [sqlite3_blob_close(P)] returns something other than [SQLITE_OK].
*/
int sqlite3_blob_close(sqlite3_blob *);
/*
** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230>
**
** Returns the size in bytes of the BLOB accessible via the open
** []BLOB handle] in its only argument.
**
** INVARIANTS:
**
** {H17843} The [sqlite3_blob_bytes(P)] interface returns the size
** in bytes of the BLOB that the [sqlite3_blob] object P
** refers to.
*/
int sqlite3_blob_bytes(sqlite3_blob *);
/*
** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230>
**
** 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.
**
** An attempt to read from an expired [BLOB handle] fails with an
** error code of [SQLITE_ABORT].
**
** On success, SQLITE_OK is returned.
** Otherwise, an [error code] or an [extended error code] is returned.
**
** INVARIANTS:
**
** {H17853} A successful invocation of [sqlite3_blob_read(P,Z,N,X)]
** shall reads N bytes of data out of the BLOB referenced by
** [BLOB handle] P beginning at offset X and store those bytes
** into buffer Z.
**
** {H17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the BLOB
** is less than N+X bytes, then the function shall leave the
** Z buffer unchanged and return [SQLITE_ERROR].
**
** {H17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
** then the function shall leave the Z buffer unchanged
** and return [SQLITE_ERROR].
**
** {H17862} The [sqlite3_blob_read(P,Z,N,X)] interface shall return [SQLITE_OK]
** if N bytes are successfully read into buffer Z.
**
** {H17863} If the [BLOB handle] P is expired and X and N are within bounds
** then [sqlite3_blob_read(P,Z,N,X)] shall leave the Z buffer
** unchanged and return [SQLITE_ABORT].
**
** {H17865} If the requested read could not be completed,
** the [sqlite3_blob_read(P,Z,N,X)] interface shall return an
** appropriate [error code] or [extended error code].
**
** {H17868} If an error occurs during evaluation of [sqlite3_blob_read(P,...)]
** then subsequent calls to [sqlite3_errcode(D)],
** [sqlite3_extended_errcode()],
** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
** information appropriate for that error, where D is the
** [database connection] that was used to open the [BLOB handle] P.
*/
int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
/*
** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230>
**
** 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.
**
** 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. If N is
** 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.
**
** On success, SQLITE_OK is returned.
** Otherwise, an [error code] or an [extended error code] is returned.
**
** INVARIANTS:
**
** {H17873} A successful invocation of [sqlite3_blob_write(P,Z,N,X)]
** shall write N bytes of data from buffer Z into the BLOB
** referenced by [BLOB handle] P beginning at offset X into
** the BLOB.
**
** {H17874} In the absence of other overridding changes, the changes
** written to a BLOB by [sqlite3_blob_write()] shall
** remain in effect after the associated [BLOB handle] expires.
**
** {H17875} If the [BLOB handle] P was opened for reading only then
** an invocation of [sqlite3_blob_write(P,Z,N,X)] shall leave
** the referenced BLOB unchanged and return [SQLITE_READONLY].
**
** {H17876} If the size of the BLOB referenced by [BLOB handle] P is
** less than N+X bytes then [sqlite3_blob_write(P,Z,N,X)] shall
** leave the BLOB unchanged and return [SQLITE_ERROR].
**
** {H17877} If the [BLOB handle] P is expired and X and N are within bounds
** then [sqlite3_blob_read(P,Z,N,X)] shall leave the BLOB
** unchanged and return [SQLITE_ABORT].
**
** {H17879} If X or N are less than zero then [sqlite3_blob_write(P,Z,N,X)]
** shall leave the BLOB referenced by [BLOB handle] P unchanged
** and return [SQLITE_ERROR].
**
** {H17882} The [sqlite3_blob_write(P,Z,N,X)] interface shall return
** [SQLITE_OK] if N bytes where successfully written into the BLOB.
**
** {H17885} If the requested write could not be completed,
** the [sqlite3_blob_write(P,Z,N,X)] interface shall return an
** appropriate [error code] or [extended error code].
**
** {H17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
** then subsequent calls to [sqlite3_errcode(D)],
** [sqlite3_extended_errcode()],
** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
** information appropriate for that error.
*/
int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
/*
** CAPI3REF: Virtual File System Objects {H11200} <S20100>
**
** 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.
**
** INVARIANTS:
**
** {H11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
** registered [sqlite3_vfs] object whose name exactly matches
** the zero-terminated UTF-8 string N, or it returns NULL if
** there is no match.
**
** {H11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
** the function returns a pointer to the default [sqlite3_vfs]
** object if there is one, or NULL if there is no default
** [sqlite3_vfs] object.
**
** {H11209} The [sqlite3_vfs_register(P,F)] interface registers the
** well-formed [sqlite3_vfs] object P using the name given
** by the zName field of the object.
**
** {H11212} Using the [sqlite3_vfs_register(P,F)] interface to register
** the same [sqlite3_vfs] object multiple times is a harmless no-op.
**
** {H11215} The [sqlite3_vfs_register(P,F)] interface makes the [sqlite3_vfs]
** object P the default [sqlite3_vfs] object if F is non-zero.
**
** {H11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
** [sqlite3_vfs] object P so that it is no longer returned by
** subsequent calls to [sqlite3_vfs_find()].
*/
sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
int sqlite3_vfs_unregister(sqlite3_vfs*);
/*
** CAPI3REF: Mutexes {H17000} <S20000>
**
** 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:
**
** <ul>
** <li> SQLITE_MUTEX_OS2
** <li> SQLITE_MUTEX_PTHREAD
** <li> SQLITE_MUTEX_W32
** <li> SQLITE_MUTEX_NOOP
** </ul>
**
** 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_OS2,
** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
** are appropriate for use on OS/2, 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().
**
** {H17011} The sqlite3_mutex_alloc() routine allocates a new
** mutex and returns a pointer to it. {H17012} If it returns NULL
** that means that a mutex could not be allocated. {H17013} SQLite
** will unwind its stack and return an error. {H17014} The argument
** to sqlite3_mutex_alloc() is one of these integer constants:
**
** <ul>
** <li> SQLITE_MUTEX_FAST
** <li> SQLITE_MUTEX_RECURSIVE
** <li> SQLITE_MUTEX_STATIC_MASTER
** <li> SQLITE_MUTEX_STATIC_MEM
** <li> SQLITE_MUTEX_STATIC_MEM2
** <li> SQLITE_MUTEX_STATIC_PRNG
** <li> SQLITE_MUTEX_STATIC_LRU
** <li> SQLITE_MUTEX_STATIC_LRU2
** </ul>
**
** {H17015} 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. {END}
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
** not want to. {H17016} But SQLite will only request a recursive mutex in
** cases where it really needs one. {END} 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.
**
** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
** a pointer to a static preexisting mutex. {END} Four 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.
**
** {H17018} 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. {H17034} But for the static
** mutex types, the same mutex is returned on every call that has
** the same type number.
**
** {H17019} The sqlite3_mutex_free() routine deallocates a previously
** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every
** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in
** use when they are deallocated. {A17022} Attempting to deallocate a static
** mutex results in undefined behavior. {H17023} SQLite never deallocates
** a static mutex. {END}
**
** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
** to enter a mutex. {H17024} If another thread is already within the mutex,
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
** SQLITE_BUSY. {H17025} The sqlite3_mutex_try() interface returns [SQLITE_OK]
** upon successful entry. {H17026} Mutexes created using
** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
** {H17027} In such cases the,
** mutex must be exited an equal number of times before another thread
** can enter. {A17028} If the same thread tries to enter any other
** kind of mutex more than once, the behavior is undefined.
** {H17029} SQLite will never exhibit
** such behavior in its own use of mutexes.
**
** 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. {H17030} The SQLite core only ever uses
** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
**
** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was
** previously entered by the same thread. {A17032} The behavior
** is undefined if the mutex is not currently entered by the
** calling thread or is not currently allocated. {H17033} SQLite will
** never do either. {END}
**
** 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()].
*/
sqlite3_mutex *sqlite3_mutex_alloc(int);
void sqlite3_mutex_free(sqlite3_mutex*);
void sqlite3_mutex_enter(sqlite3_mutex*);
int sqlite3_mutex_try(sqlite3_mutex*);
void sqlite3_mutex_leave(sqlite3_mutex*);
/*
** CAPI3REF: Mutex Methods Object {H17120} <S20130>
** EXPERIMENTAL
**
** 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 user 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 user
** 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.
** {H17001} The xMutexInit routine shall be called by SQLite 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. {H17003} The xMutexEnd()
** interface shall be invoked 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):
**
** <ul>
** <li> [sqlite3_mutex_alloc()] </li>
** <li> [sqlite3_mutex_free()] </li>
** <li> [sqlite3_mutex_enter()] </li>
** <li> [sqlite3_mutex_try()] </li>
** <li> [sqlite3_mutex_leave()] </li>
** <li> [sqlite3_mutex_held()] </li>
** <li> [sqlite3_mutex_notheld()] </li>
** </ul>
**
** 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).
*/
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 {H17080} <S20130> <S30800>
**
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
** are intended for use inside assert() statements. {H17081} The SQLite core
** never uses these routines except inside an assert() and applications
** are advised to follow the lead of the core. {H17082} The core only
** provides implementations for these routines when it is compiled
** with the SQLITE_DEBUG flag. {A17087} External mutex implementations
** are only required to provide these routines if SQLITE_DEBUG is
** defined and if NDEBUG is not defined.
**
** {H17083} These routines should return true if the mutex in their argument
** is held or not held, respectively, by the calling thread.
**
** {X17084} The implementation is not required to provided 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.
**
** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
** the routine should return 1. {END} This seems counter-intuitive since
** clearly the mutex cannot be held if it does not exist. But the
** 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. {H17086} The sqlite3_mutex_notheld()
** interface should also return 1 when given a NULL pointer.
*/
int sqlite3_mutex_held(sqlite3_mutex*);
int sqlite3_mutex_notheld(sqlite3_mutex*);
/*
** CAPI3REF: Mutex Types {H17001} <H17000>
**
** 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 /* sqlite3_release_memory() */
#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
#define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */
/*
** CAPI3REF: Retrieve the mutex for a database connection {H17002} <H17000>
**
** 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.
*/
sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
/*
** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800>
**
** {H11301} 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. {H11302} The
** name of the database is the name assigned to the database by the
** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
** database. {H11303} To control the main database file, use the name "main"
** or a NULL pointer. {H11304} The third and fourth parameters to this routine
** are passed directly through to the second and third parameters of
** the xFileControl method. {H11305} The return value of the xFileControl
** method becomes the return value of this routine.
**
** {H11306} If the second parameter (zDbName) does not match the name of any
** open database file, then SQLITE_ERROR is returned. {H11307} This error
** code is not remembered and will not be recalled by [sqlite3_errcode()]
** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
** also return SQLITE_ERROR. {A11309} There is no way to distinguish between
** an incorrect zDbName and an SQLITE_ERROR return from the underlying
** xFileControl method. {END}
**
** See also: [SQLITE_FCNTL_LOCKSTATE]
*/
int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
/*
** CAPI3REF: Testing Interface {H11400} <S30800>
**
** 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.
*/
int sqlite3_test_control(int op, ...);
/*
** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400>
**
** 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_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
/*
** CAPI3REF: SQLite Runtime Status {H17200} <S60200>
** EXPERIMENTAL
**
** This interface is used to retrieve runtime status information
** about the preformance 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 [SQLITE_STATUS_MEMORY_USED | 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.
**
** This routine returns SQLITE_OK on success and a non-zero
** [error code] on failure.
**
** This routine is threadsafe but is not atomic. This routine can
** called while other threads are running the same or different SQLite
** interfaces. However the values returned in *pCurrent and
** *pHighwater reflect the status of SQLite at different points in time
** and it is possible that another thread might change the parameter
** in between the times when *pCurrent and *pHighwater are written.
**
** See also: [sqlite3_db_status()]
*/
SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
/*
** CAPI3REF: Status Parameters {H17250} <H17200>
** EXPERIMENTAL
**
** These integer constants designate various run-time status parameters
** that can be returned by [sqlite3_status()].
**
** <dl>
** <dt>SQLITE_STATUS_MEMORY_USED</dt>
** <dd>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. Scratch memory
** controlled by [SQLITE_CONFIG_SCRATCH] and 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].</dd>
**
** <dt>SQLITE_STATUS_MALLOC_SIZE</dt>
** <dd>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.</dd>
**
** <dt>SQLITE_STATUS_PAGECACHE_USED</dt>
** <dd>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.</dd>
**
** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
** <dd>This parameter returns the number of bytes of page cache
** allocation which could not be statisfied 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.</dd>
**
** <dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
** <dd>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.</dd>
**
** <dt>SQLITE_STATUS_SCRATCH_USED</dt>
** <dd>This parameter returns the number of allocations used out of the
** [scratch memory allocator] configured using
** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
** in bytes. Since a single thread may only have one scratch allocation
** outstanding at time, this parameter also reports the number of threads
** using scratch memory at the same time.</dd>
**
** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
** <dd>This parameter returns the number of bytes of scratch memory
** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
** buffer and where forced to overflow to [sqlite3_malloc()]. The values
** returned include overflows because the requested allocation was too
** larger (that is, because the requested allocation was larger than the
** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
** slots were available.
** </dd>
**
** <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
** <dd>This parameter records the largest memory allocation request
** handed to [scratch 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.</dd>
**
** <dt>SQLITE_STATUS_PARSER_STACK</dt>
** <dd>This parameter records the deepest parser stack. It is only
** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>
** </dl>
**
** 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
#define SQLITE_STATUS_SCRATCH_OVERFLOW 4
#define SQLITE_STATUS_MALLOC_SIZE 5
#define SQLITE_STATUS_PARSER_STACK 6
#define SQLITE_STATUS_PAGECACHE_SIZE 7
#define SQLITE_STATUS_SCRATCH_SIZE 8
/*
** CAPI3REF: Database Connection Status {H17500} <S60200>
** EXPERIMENTAL
**
** 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 the parameter to interrogate. Currently, the only allowed value
** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED].
** Additional options will likely appear 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.
**
** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
*/
SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
/*
** CAPI3REF: Status Parameters for database connections {H17520} <H17500>
** EXPERIMENTAL
**
** Status verbs for [sqlite3_db_status()].
**
** <dl>
** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
** <dd>This parameter returns the number of lookaside memory slots currently
** checked out.</dd>
** </dl>
*/
#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
/*
** CAPI3REF: Prepared Statement Status {H17550} <S60200>
** EXPERIMENTAL
**
** Each prepared statement maintains various
** [SQLITE_STMTSTATUS_SORT | 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_SORT | 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_EXPERIMENTAL int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
/*
** CAPI3REF: Status Parameters for prepared statements {H17570} <H17550>
** EXPERIMENTAL
**
** 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:
**
** <dl>
** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
** <dd>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.</dd>
**
** <dt>SQLITE_STMTSTATUS_SORT</dt>
** <dd>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.</dd>
**
** </dl>
*/
#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
#define SQLITE_STMTSTATUS_SORT 2
/*
** CAPI3REF: Custom Page Cache Object
** EXPERIMENTAL
**
** 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_methods] for additional information.
*/
typedef struct sqlite3_pcache sqlite3_pcache;
/*
** CAPI3REF: Application Defined Page Cache.
** EXPERIMENTAL
**
** The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
** register an alternative page cache implementation by passing in an
** instance of the sqlite3_pcache_methods structure. The majority of the
** heap memory used by sqlite is used by the page cache to cache data read
** from, or ready to be written to, the database file. By implementing a
** custom page cache using this API, an application can control more
** precisely the amount of memory consumed by sqlite, the way in which
** said 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 contents of the structure are copied to an internal buffer by sqlite
** within the call to [sqlite3_config].
**
** The xInit() method is called once for each call to [sqlite3_initialize()]
** (usually only once during the lifetime of the process). It is passed
** a copy of the sqlite3_pcache_methods.pArg value. It can be used to set
** up global structures and mutexes required by the custom page cache
** implementation. The xShutdown() method is called from within
** [sqlite3_shutdown()], if the application invokes this API. It can be used
** to clean up any outstanding resources before process shutdown, if required.
**
** The xCreate() method is used to construct a new cache instance. The
** first parameter, szPage, is the size in bytes of the pages that must
** be allocated by the cache. szPage will not be a power of two. The
** second argument, bPurgeable, is true if the cache being created will
** be used to cache database pages read from 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 on the value of bPurgeable,
** it is purely advisory.
**
** 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 special with this
** value, it is advisory only.
**
** The xPagecount() method should return the number of pages currently
** stored in the cache supplied as an argument.
**
** The xFetch() method is used to fetch a page and return a pointer to it.
** A 'page', in this context, is a buffer of szPage bytes aligned at an
** 8-byte boundary. The page to be fetched is determined by the key. The
** mimimum 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 a pointer to
** the cached buffer should be returned with its contents intact. If the
** page is not already in the cache, then the expected behaviour of the
** cache is determined by the value of the createFlag parameter passed
** to xFetch, according to the following table:
**
** <table border=1 width=85% align=center>
** <tr><th>createFlag<th>Expected Behaviour
** <tr><td>0<td>NULL should be returned. No new cache entry is created.
** <tr><td>1<td>If createFlag is set to 1, this indicates that
** SQLite is holding pinned pages that can be unpinned
** by writing their contents to the database file (a
** relatively expensive operation). In this situation the
** cache implementation has two choices: it can return NULL,
** in which case SQLite will attempt to unpin one or more
** pages before re-requesting the same page, or it can
** allocate a new page and return a pointer to it. If a new
** page is allocated, then it must be completely zeroed before
** it is returned.
** <tr><td>2<td>If createFlag is set to 2, then SQLite is not holding any
** pinned pages associated with the specific cache passed
** as the first argument to xFetch() that can be unpinned. The
** cache implementation should attempt to allocate a new
** cache entry and return a pointer to it. Again, the new
** page should be zeroed before it is returned. If the xFetch()
** method returns NULL when createFlag==2, SQLite assumes that
** a memory allocation failed and returns SQLITE_NOMEM to the
** user.
** </table>
**
** 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 should be evicted from the cache. In this case SQLite
** assumes that the next time the page is retrieved from the cache using
** the xFetch() method, it will be zeroed. If the discard parameter is
** zero, then the page is considered to be unpinned. The cache implementation
** may choose to reclaim (free or recycle) unpinned pages at any time.
** SQLite assumes that next time the page is retrieved from the cache
** it will either be zeroed, or contain the same data that it did when it
** was unpinned.
**
** The cache is not required to perform any reference counting. A single
** call to xUnpin() unpins the page regardless of the number of prior calls
** to xFetch().
**
** The xRekey() method is used to change the key value associated with the
** page passed as the second argument from oldKey to newKey. If the cache
** previously contains an entry associated with newKey, it should 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() 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_methods
** functions.
*/
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*);
};
/*
** 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
#ifdef __cplusplus
} /* End of the 'extern "C"' block */
#endif
#endif
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