1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/sqlite3.c Thu Mar 26 15:30:21 2015 +0100
1.3 @@ -0,0 +1,148882 @@
1.4 +/******************************************************************************
1.5 +** This file is an amalgamation of many separate C source files from SQLite
1.6 +** version 3.8.6. By combining all the individual C code files into this
1.7 +** single large file, the entire code can be compiled as a single translation
1.8 +** unit. This allows many compilers to do optimizations that would not be
1.9 +** possible if the files were compiled separately. Performance improvements
1.10 +** of 5% or more are commonly seen when SQLite is compiled as a single
1.11 +** translation unit.
1.12 +**
1.13 +** This file is all you need to compile SQLite. To use SQLite in other
1.14 +** programs, you need this file and the "sqlite3.h" header file that defines
1.15 +** the programming interface to the SQLite library. (If you do not have
1.16 +** the "sqlite3.h" header file at hand, you will find a copy embedded within
1.17 +** the text of this file. Search for "Begin file sqlite3.h" to find the start
1.18 +** of the embedded sqlite3.h header file.) Additional code files may be needed
1.19 +** if you want a wrapper to interface SQLite with your choice of programming
1.20 +** language. The code for the "sqlite3" command-line shell is also in a
1.21 +** separate file. This file contains only code for the core SQLite library.
1.22 +*/
1.23 +#define SQLITE_CORE 1
1.24 +#define SQLITE_AMALGAMATION 1
1.25 +#ifndef SQLITE_PRIVATE
1.26 +# define SQLITE_PRIVATE static
1.27 +#endif
1.28 +#ifndef SQLITE_API
1.29 +# define SQLITE_API
1.30 +#endif
1.31 +/************** Begin file sqliteInt.h ***************************************/
1.32 +/*
1.33 +** 2001 September 15
1.34 +**
1.35 +** The author disclaims copyright to this source code. In place of
1.36 +** a legal notice, here is a blessing:
1.37 +**
1.38 +** May you do good and not evil.
1.39 +** May you find forgiveness for yourself and forgive others.
1.40 +** May you share freely, never taking more than you give.
1.41 +**
1.42 +*************************************************************************
1.43 +** Internal interface definitions for SQLite.
1.44 +**
1.45 +*/
1.46 +#ifndef _SQLITEINT_H_
1.47 +#define _SQLITEINT_H_
1.48 +
1.49 +/*
1.50 +** These #defines should enable >2GB file support on POSIX if the
1.51 +** underlying operating system supports it. If the OS lacks
1.52 +** large file support, or if the OS is windows, these should be no-ops.
1.53 +**
1.54 +** Ticket #2739: The _LARGEFILE_SOURCE macro must appear before any
1.55 +** system #includes. Hence, this block of code must be the very first
1.56 +** code in all source files.
1.57 +**
1.58 +** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
1.59 +** on the compiler command line. This is necessary if you are compiling
1.60 +** on a recent machine (ex: Red Hat 7.2) but you want your code to work
1.61 +** on an older machine (ex: Red Hat 6.0). If you compile on Red Hat 7.2
1.62 +** without this option, LFS is enable. But LFS does not exist in the kernel
1.63 +** in Red Hat 6.0, so the code won't work. Hence, for maximum binary
1.64 +** portability you should omit LFS.
1.65 +**
1.66 +** The previous paragraph was written in 2005. (This paragraph is written
1.67 +** on 2008-11-28.) These days, all Linux kernels support large files, so
1.68 +** you should probably leave LFS enabled. But some embedded platforms might
1.69 +** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
1.70 +**
1.71 +** Similar is true for Mac OS X. LFS is only supported on Mac OS X 9 and later.
1.72 +*/
1.73 +#ifndef SQLITE_DISABLE_LFS
1.74 +# define _LARGE_FILE 1
1.75 +# ifndef _FILE_OFFSET_BITS
1.76 +# define _FILE_OFFSET_BITS 64
1.77 +# endif
1.78 +# define _LARGEFILE_SOURCE 1
1.79 +#endif
1.80 +
1.81 +/*
1.82 +** For MinGW, check to see if we can include the header file containing its
1.83 +** version information, among other things. Normally, this internal MinGW
1.84 +** header file would [only] be included automatically by other MinGW header
1.85 +** files; however, the contained version information is now required by this
1.86 +** header file to work around binary compatibility issues (see below) and
1.87 +** this is the only known way to reliably obtain it. This entire #if block
1.88 +** would be completely unnecessary if there was any other way of detecting
1.89 +** MinGW via their preprocessor (e.g. if they customized their GCC to define
1.90 +** some MinGW-specific macros). When compiling for MinGW, either the
1.91 +** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
1.92 +** defined; otherwise, detection of conditions specific to MinGW will be
1.93 +** disabled.
1.94 +*/
1.95 +#if defined(_HAVE_MINGW_H)
1.96 +# include "mingw.h"
1.97 +#elif defined(_HAVE__MINGW_H)
1.98 +# include "_mingw.h"
1.99 +#endif
1.100 +
1.101 +/*
1.102 +** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
1.103 +** define is required to maintain binary compatibility with the MSVC runtime
1.104 +** library in use (e.g. for Windows XP).
1.105 +*/
1.106 +#if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
1.107 + defined(_WIN32) && !defined(_WIN64) && \
1.108 + defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
1.109 + defined(__MSVCRT__)
1.110 +# define _USE_32BIT_TIME_T
1.111 +#endif
1.112 +
1.113 +/* The public SQLite interface. The _FILE_OFFSET_BITS macro must appear
1.114 +** first in QNX. Also, the _USE_32BIT_TIME_T macro must appear first for
1.115 +** MinGW.
1.116 +*/
1.117 +/************** Include sqlite3.h in the middle of sqliteInt.h ***************/
1.118 +/************** Begin file sqlite3.h *****************************************/
1.119 +/*
1.120 +** 2001 September 15
1.121 +**
1.122 +** The author disclaims copyright to this source code. In place of
1.123 +** a legal notice, here is a blessing:
1.124 +**
1.125 +** May you do good and not evil.
1.126 +** May you find forgiveness for yourself and forgive others.
1.127 +** May you share freely, never taking more than you give.
1.128 +**
1.129 +*************************************************************************
1.130 +** This header file defines the interface that the SQLite library
1.131 +** presents to client programs. If a C-function, structure, datatype,
1.132 +** or constant definition does not appear in this file, then it is
1.133 +** not a published API of SQLite, is subject to change without
1.134 +** notice, and should not be referenced by programs that use SQLite.
1.135 +**
1.136 +** Some of the definitions that are in this file are marked as
1.137 +** "experimental". Experimental interfaces are normally new
1.138 +** features recently added to SQLite. We do not anticipate changes
1.139 +** to experimental interfaces but reserve the right to make minor changes
1.140 +** if experience from use "in the wild" suggest such changes are prudent.
1.141 +**
1.142 +** The official C-language API documentation for SQLite is derived
1.143 +** from comments in this file. This file is the authoritative source
1.144 +** on how SQLite interfaces are suppose to operate.
1.145 +**
1.146 +** The name of this file under configuration management is "sqlite.h.in".
1.147 +** The makefile makes some minor changes to this file (such as inserting
1.148 +** the version number) and changes its name to "sqlite3.h" as
1.149 +** part of the build process.
1.150 +*/
1.151 +#ifndef _SQLITE3_H_
1.152 +#define _SQLITE3_H_
1.153 +#include <stdarg.h> /* Needed for the definition of va_list */
1.154 +
1.155 +/*
1.156 +** Make sure we can call this stuff from C++.
1.157 +*/
1.158 +#if 0
1.159 +extern "C" {
1.160 +#endif
1.161 +
1.162 +
1.163 +/*
1.164 +** Add the ability to override 'extern'
1.165 +*/
1.166 +#ifndef SQLITE_EXTERN
1.167 +# define SQLITE_EXTERN extern
1.168 +#endif
1.169 +
1.170 +#ifndef SQLITE_API
1.171 +# define SQLITE_API
1.172 +#endif
1.173 +
1.174 +
1.175 +/*
1.176 +** These no-op macros are used in front of interfaces to mark those
1.177 +** interfaces as either deprecated or experimental. New applications
1.178 +** should not use deprecated interfaces - they are support for backwards
1.179 +** compatibility only. Application writers should be aware that
1.180 +** experimental interfaces are subject to change in point releases.
1.181 +**
1.182 +** These macros used to resolve to various kinds of compiler magic that
1.183 +** would generate warning messages when they were used. But that
1.184 +** compiler magic ended up generating such a flurry of bug reports
1.185 +** that we have taken it all out and gone back to using simple
1.186 +** noop macros.
1.187 +*/
1.188 +#define SQLITE_DEPRECATED
1.189 +#define SQLITE_EXPERIMENTAL
1.190 +
1.191 +/*
1.192 +** Ensure these symbols were not defined by some previous header file.
1.193 +*/
1.194 +#ifdef SQLITE_VERSION
1.195 +# undef SQLITE_VERSION
1.196 +#endif
1.197 +#ifdef SQLITE_VERSION_NUMBER
1.198 +# undef SQLITE_VERSION_NUMBER
1.199 +#endif
1.200 +
1.201 +/*
1.202 +** CAPI3REF: Compile-Time Library Version Numbers
1.203 +**
1.204 +** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
1.205 +** evaluates to a string literal that is the SQLite version in the
1.206 +** format "X.Y.Z" where X is the major version number (always 3 for
1.207 +** SQLite3) and Y is the minor version number and Z is the release number.)^
1.208 +** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
1.209 +** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
1.210 +** numbers used in [SQLITE_VERSION].)^
1.211 +** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
1.212 +** be larger than the release from which it is derived. Either Y will
1.213 +** be held constant and Z will be incremented or else Y will be incremented
1.214 +** and Z will be reset to zero.
1.215 +**
1.216 +** Since version 3.6.18, SQLite source code has been stored in the
1.217 +** <a href="http://www.fossil-scm.org/">Fossil configuration management
1.218 +** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
1.219 +** a string which identifies a particular check-in of SQLite
1.220 +** within its configuration management system. ^The SQLITE_SOURCE_ID
1.221 +** string contains the date and time of the check-in (UTC) and an SHA1
1.222 +** hash of the entire source tree.
1.223 +**
1.224 +** See also: [sqlite3_libversion()],
1.225 +** [sqlite3_libversion_number()], [sqlite3_sourceid()],
1.226 +** [sqlite_version()] and [sqlite_source_id()].
1.227 +*/
1.228 +#define SQLITE_VERSION "3.8.6"
1.229 +#define SQLITE_VERSION_NUMBER 3008006
1.230 +#define SQLITE_SOURCE_ID "2014-08-15 11:46:33 9491ba7d738528f168657adb43a198238abde19e"
1.231 +
1.232 +/*
1.233 +** CAPI3REF: Run-Time Library Version Numbers
1.234 +** KEYWORDS: sqlite3_version, sqlite3_sourceid
1.235 +**
1.236 +** These interfaces provide the same information as the [SQLITE_VERSION],
1.237 +** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
1.238 +** but are associated with the library instead of the header file. ^(Cautious
1.239 +** programmers might include assert() statements in their application to
1.240 +** verify that values returned by these interfaces match the macros in
1.241 +** the header, and thus insure that the application is
1.242 +** compiled with matching library and header files.
1.243 +**
1.244 +** <blockquote><pre>
1.245 +** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
1.246 +** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
1.247 +** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
1.248 +** </pre></blockquote>)^
1.249 +**
1.250 +** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
1.251 +** macro. ^The sqlite3_libversion() function returns a pointer to the
1.252 +** to the sqlite3_version[] string constant. The sqlite3_libversion()
1.253 +** function is provided for use in DLLs since DLL users usually do not have
1.254 +** direct access to string constants within the DLL. ^The
1.255 +** sqlite3_libversion_number() function returns an integer equal to
1.256 +** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
1.257 +** a pointer to a string constant whose value is the same as the
1.258 +** [SQLITE_SOURCE_ID] C preprocessor macro.
1.259 +**
1.260 +** See also: [sqlite_version()] and [sqlite_source_id()].
1.261 +*/
1.262 +SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
1.263 +SQLITE_API const char *sqlite3_libversion(void);
1.264 +SQLITE_API const char *sqlite3_sourceid(void);
1.265 +SQLITE_API int sqlite3_libversion_number(void);
1.266 +
1.267 +/*
1.268 +** CAPI3REF: Run-Time Library Compilation Options Diagnostics
1.269 +**
1.270 +** ^The sqlite3_compileoption_used() function returns 0 or 1
1.271 +** indicating whether the specified option was defined at
1.272 +** compile time. ^The SQLITE_ prefix may be omitted from the
1.273 +** option name passed to sqlite3_compileoption_used().
1.274 +**
1.275 +** ^The sqlite3_compileoption_get() function allows iterating
1.276 +** over the list of options that were defined at compile time by
1.277 +** returning the N-th compile time option string. ^If N is out of range,
1.278 +** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
1.279 +** prefix is omitted from any strings returned by
1.280 +** sqlite3_compileoption_get().
1.281 +**
1.282 +** ^Support for the diagnostic functions sqlite3_compileoption_used()
1.283 +** and sqlite3_compileoption_get() may be omitted by specifying the
1.284 +** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
1.285 +**
1.286 +** See also: SQL functions [sqlite_compileoption_used()] and
1.287 +** [sqlite_compileoption_get()] and the [compile_options pragma].
1.288 +*/
1.289 +#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
1.290 +SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
1.291 +SQLITE_API const char *sqlite3_compileoption_get(int N);
1.292 +#endif
1.293 +
1.294 +/*
1.295 +** CAPI3REF: Test To See If The Library Is Threadsafe
1.296 +**
1.297 +** ^The sqlite3_threadsafe() function returns zero if and only if
1.298 +** SQLite was compiled with mutexing code omitted due to the
1.299 +** [SQLITE_THREADSAFE] compile-time option being set to 0.
1.300 +**
1.301 +** SQLite can be compiled with or without mutexes. When
1.302 +** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
1.303 +** are enabled and SQLite is threadsafe. When the
1.304 +** [SQLITE_THREADSAFE] macro is 0,
1.305 +** the mutexes are omitted. Without the mutexes, it is not safe
1.306 +** to use SQLite concurrently from more than one thread.
1.307 +**
1.308 +** Enabling mutexes incurs a measurable performance penalty.
1.309 +** So if speed is of utmost importance, it makes sense to disable
1.310 +** the mutexes. But for maximum safety, mutexes should be enabled.
1.311 +** ^The default behavior is for mutexes to be enabled.
1.312 +**
1.313 +** This interface can be used by an application to make sure that the
1.314 +** version of SQLite that it is linking against was compiled with
1.315 +** the desired setting of the [SQLITE_THREADSAFE] macro.
1.316 +**
1.317 +** This interface only reports on the compile-time mutex setting
1.318 +** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
1.319 +** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
1.320 +** can be fully or partially disabled using a call to [sqlite3_config()]
1.321 +** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
1.322 +** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
1.323 +** sqlite3_threadsafe() function shows only the compile-time setting of
1.324 +** thread safety, not any run-time changes to that setting made by
1.325 +** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
1.326 +** is unchanged by calls to sqlite3_config().)^
1.327 +**
1.328 +** See the [threading mode] documentation for additional information.
1.329 +*/
1.330 +SQLITE_API int sqlite3_threadsafe(void);
1.331 +
1.332 +/*
1.333 +** CAPI3REF: Database Connection Handle
1.334 +** KEYWORDS: {database connection} {database connections}
1.335 +**
1.336 +** Each open SQLite database is represented by a pointer to an instance of
1.337 +** the opaque structure named "sqlite3". It is useful to think of an sqlite3
1.338 +** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
1.339 +** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
1.340 +** and [sqlite3_close_v2()] are its destructors. There are many other
1.341 +** interfaces (such as
1.342 +** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
1.343 +** [sqlite3_busy_timeout()] to name but three) that are methods on an
1.344 +** sqlite3 object.
1.345 +*/
1.346 +typedef struct sqlite3 sqlite3;
1.347 +
1.348 +/*
1.349 +** CAPI3REF: 64-Bit Integer Types
1.350 +** KEYWORDS: sqlite_int64 sqlite_uint64
1.351 +**
1.352 +** Because there is no cross-platform way to specify 64-bit integer types
1.353 +** SQLite includes typedefs for 64-bit signed and unsigned integers.
1.354 +**
1.355 +** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
1.356 +** The sqlite_int64 and sqlite_uint64 types are supported for backwards
1.357 +** compatibility only.
1.358 +**
1.359 +** ^The sqlite3_int64 and sqlite_int64 types can store integer values
1.360 +** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
1.361 +** sqlite3_uint64 and sqlite_uint64 types can store integer values
1.362 +** between 0 and +18446744073709551615 inclusive.
1.363 +*/
1.364 +#ifdef SQLITE_INT64_TYPE
1.365 + typedef SQLITE_INT64_TYPE sqlite_int64;
1.366 + typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
1.367 +#elif defined(_MSC_VER) || defined(__BORLANDC__)
1.368 + typedef __int64 sqlite_int64;
1.369 + typedef unsigned __int64 sqlite_uint64;
1.370 +#else
1.371 + typedef long long int sqlite_int64;
1.372 + typedef unsigned long long int sqlite_uint64;
1.373 +#endif
1.374 +typedef sqlite_int64 sqlite3_int64;
1.375 +typedef sqlite_uint64 sqlite3_uint64;
1.376 +
1.377 +/*
1.378 +** If compiling for a processor that lacks floating point support,
1.379 +** substitute integer for floating-point.
1.380 +*/
1.381 +#ifdef SQLITE_OMIT_FLOATING_POINT
1.382 +# define double sqlite3_int64
1.383 +#endif
1.384 +
1.385 +/*
1.386 +** CAPI3REF: Closing A Database Connection
1.387 +**
1.388 +** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
1.389 +** for the [sqlite3] object.
1.390 +** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
1.391 +** the [sqlite3] object is successfully destroyed and all associated
1.392 +** resources are deallocated.
1.393 +**
1.394 +** ^If the database connection is associated with unfinalized prepared
1.395 +** statements or unfinished sqlite3_backup objects then sqlite3_close()
1.396 +** will leave the database connection open and return [SQLITE_BUSY].
1.397 +** ^If sqlite3_close_v2() is called with unfinalized prepared statements
1.398 +** and/or unfinished sqlite3_backups, then the database connection becomes
1.399 +** an unusable "zombie" which will automatically be deallocated when the
1.400 +** last prepared statement is finalized or the last sqlite3_backup is
1.401 +** finished. The sqlite3_close_v2() interface is intended for use with
1.402 +** host languages that are garbage collected, and where the order in which
1.403 +** destructors are called is arbitrary.
1.404 +**
1.405 +** Applications should [sqlite3_finalize | finalize] all [prepared statements],
1.406 +** [sqlite3_blob_close | close] all [BLOB handles], and
1.407 +** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
1.408 +** with the [sqlite3] object prior to attempting to close the object. ^If
1.409 +** sqlite3_close_v2() is called on a [database connection] that still has
1.410 +** outstanding [prepared statements], [BLOB handles], and/or
1.411 +** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
1.412 +** of resources is deferred until all [prepared statements], [BLOB handles],
1.413 +** and [sqlite3_backup] objects are also destroyed.
1.414 +**
1.415 +** ^If an [sqlite3] object is destroyed while a transaction is open,
1.416 +** the transaction is automatically rolled back.
1.417 +**
1.418 +** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
1.419 +** must be either a NULL
1.420 +** pointer or an [sqlite3] object pointer obtained
1.421 +** from [sqlite3_open()], [sqlite3_open16()], or
1.422 +** [sqlite3_open_v2()], and not previously closed.
1.423 +** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
1.424 +** argument is a harmless no-op.
1.425 +*/
1.426 +SQLITE_API int sqlite3_close(sqlite3*);
1.427 +SQLITE_API int sqlite3_close_v2(sqlite3*);
1.428 +
1.429 +/*
1.430 +** The type for a callback function.
1.431 +** This is legacy and deprecated. It is included for historical
1.432 +** compatibility and is not documented.
1.433 +*/
1.434 +typedef int (*sqlite3_callback)(void*,int,char**, char**);
1.435 +
1.436 +/*
1.437 +** CAPI3REF: One-Step Query Execution Interface
1.438 +**
1.439 +** The sqlite3_exec() interface is a convenience wrapper around
1.440 +** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
1.441 +** that allows an application to run multiple statements of SQL
1.442 +** without having to use a lot of C code.
1.443 +**
1.444 +** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
1.445 +** semicolon-separate SQL statements passed into its 2nd argument,
1.446 +** in the context of the [database connection] passed in as its 1st
1.447 +** argument. ^If the callback function of the 3rd argument to
1.448 +** sqlite3_exec() is not NULL, then it is invoked for each result row
1.449 +** coming out of the evaluated SQL statements. ^The 4th argument to
1.450 +** sqlite3_exec() is relayed through to the 1st argument of each
1.451 +** callback invocation. ^If the callback pointer to sqlite3_exec()
1.452 +** is NULL, then no callback is ever invoked and result rows are
1.453 +** ignored.
1.454 +**
1.455 +** ^If an error occurs while evaluating the SQL statements passed into
1.456 +** sqlite3_exec(), then execution of the current statement stops and
1.457 +** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
1.458 +** is not NULL then any error message is written into memory obtained
1.459 +** from [sqlite3_malloc()] and passed back through the 5th parameter.
1.460 +** To avoid memory leaks, the application should invoke [sqlite3_free()]
1.461 +** on error message strings returned through the 5th parameter of
1.462 +** of sqlite3_exec() after the error message string is no longer needed.
1.463 +** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
1.464 +** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
1.465 +** NULL before returning.
1.466 +**
1.467 +** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
1.468 +** routine returns SQLITE_ABORT without invoking the callback again and
1.469 +** without running any subsequent SQL statements.
1.470 +**
1.471 +** ^The 2nd argument to the sqlite3_exec() callback function is the
1.472 +** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
1.473 +** callback is an array of pointers to strings obtained as if from
1.474 +** [sqlite3_column_text()], one for each column. ^If an element of a
1.475 +** result row is NULL then the corresponding string pointer for the
1.476 +** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
1.477 +** sqlite3_exec() callback is an array of pointers to strings where each
1.478 +** entry represents the name of corresponding result column as obtained
1.479 +** from [sqlite3_column_name()].
1.480 +**
1.481 +** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
1.482 +** to an empty string, or a pointer that contains only whitespace and/or
1.483 +** SQL comments, then no SQL statements are evaluated and the database
1.484 +** is not changed.
1.485 +**
1.486 +** Restrictions:
1.487 +**
1.488 +** <ul>
1.489 +** <li> The application must insure that the 1st parameter to sqlite3_exec()
1.490 +** is a valid and open [database connection].
1.491 +** <li> The application must not close the [database connection] specified by
1.492 +** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
1.493 +** <li> The application must not modify the SQL statement text passed into
1.494 +** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
1.495 +** </ul>
1.496 +*/
1.497 +SQLITE_API int sqlite3_exec(
1.498 + sqlite3*, /* An open database */
1.499 + const char *sql, /* SQL to be evaluated */
1.500 + int (*callback)(void*,int,char**,char**), /* Callback function */
1.501 + void *, /* 1st argument to callback */
1.502 + char **errmsg /* Error msg written here */
1.503 +);
1.504 +
1.505 +/*
1.506 +** CAPI3REF: Result Codes
1.507 +** KEYWORDS: {result code definitions}
1.508 +**
1.509 +** Many SQLite functions return an integer result code from the set shown
1.510 +** here in order to indicate success or failure.
1.511 +**
1.512 +** New error codes may be added in future versions of SQLite.
1.513 +**
1.514 +** See also: [extended result code definitions]
1.515 +*/
1.516 +#define SQLITE_OK 0 /* Successful result */
1.517 +/* beginning-of-error-codes */
1.518 +#define SQLITE_ERROR 1 /* SQL error or missing database */
1.519 +#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
1.520 +#define SQLITE_PERM 3 /* Access permission denied */
1.521 +#define SQLITE_ABORT 4 /* Callback routine requested an abort */
1.522 +#define SQLITE_BUSY 5 /* The database file is locked */
1.523 +#define SQLITE_LOCKED 6 /* A table in the database is locked */
1.524 +#define SQLITE_NOMEM 7 /* A malloc() failed */
1.525 +#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
1.526 +#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
1.527 +#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
1.528 +#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
1.529 +#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
1.530 +#define SQLITE_FULL 13 /* Insertion failed because database is full */
1.531 +#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
1.532 +#define SQLITE_PROTOCOL 15 /* Database lock protocol error */
1.533 +#define SQLITE_EMPTY 16 /* Database is empty */
1.534 +#define SQLITE_SCHEMA 17 /* The database schema changed */
1.535 +#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
1.536 +#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
1.537 +#define SQLITE_MISMATCH 20 /* Data type mismatch */
1.538 +#define SQLITE_MISUSE 21 /* Library used incorrectly */
1.539 +#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
1.540 +#define SQLITE_AUTH 23 /* Authorization denied */
1.541 +#define SQLITE_FORMAT 24 /* Auxiliary database format error */
1.542 +#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
1.543 +#define SQLITE_NOTADB 26 /* File opened that is not a database file */
1.544 +#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
1.545 +#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
1.546 +#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
1.547 +#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
1.548 +/* end-of-error-codes */
1.549 +
1.550 +/*
1.551 +** CAPI3REF: Extended Result Codes
1.552 +** KEYWORDS: {extended result code definitions}
1.553 +**
1.554 +** In its default configuration, SQLite API routines return one of 30 integer
1.555 +** [result codes]. However, experience has shown that many of
1.556 +** these result codes are too coarse-grained. They do not provide as
1.557 +** much information about problems as programmers might like. In an effort to
1.558 +** address this, newer versions of SQLite (version 3.3.8 and later) include
1.559 +** support for additional result codes that provide more detailed information
1.560 +** about errors. These [extended result codes] are enabled or disabled
1.561 +** on a per database connection basis using the
1.562 +** [sqlite3_extended_result_codes()] API. Or, the extended code for
1.563 +** the most recent error can be obtained using
1.564 +** [sqlite3_extended_errcode()].
1.565 +*/
1.566 +#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
1.567 +#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
1.568 +#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
1.569 +#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
1.570 +#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
1.571 +#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
1.572 +#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
1.573 +#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
1.574 +#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
1.575 +#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
1.576 +#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
1.577 +#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
1.578 +#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
1.579 +#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
1.580 +#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
1.581 +#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
1.582 +#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
1.583 +#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
1.584 +#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
1.585 +#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
1.586 +#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
1.587 +#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
1.588 +#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
1.589 +#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
1.590 +#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
1.591 +#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
1.592 +#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
1.593 +#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
1.594 +#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
1.595 +#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
1.596 +#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
1.597 +#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
1.598 +#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
1.599 +#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
1.600 +#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
1.601 +#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
1.602 +#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
1.603 +#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
1.604 +#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
1.605 +#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
1.606 +#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
1.607 +#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
1.608 +#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
1.609 +#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
1.610 +#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
1.611 +#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
1.612 +#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
1.613 +#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
1.614 +#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
1.615 +#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
1.616 +#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
1.617 +#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
1.618 +
1.619 +/*
1.620 +** CAPI3REF: Flags For File Open Operations
1.621 +**
1.622 +** These bit values are intended for use in the
1.623 +** 3rd parameter to the [sqlite3_open_v2()] interface and
1.624 +** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
1.625 +*/
1.626 +#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
1.627 +#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
1.628 +#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
1.629 +#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
1.630 +#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
1.631 +#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
1.632 +#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
1.633 +#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
1.634 +#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
1.635 +#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
1.636 +#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
1.637 +#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
1.638 +#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
1.639 +#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
1.640 +#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
1.641 +#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
1.642 +#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
1.643 +#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
1.644 +#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
1.645 +#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
1.646 +
1.647 +/* Reserved: 0x00F00000 */
1.648 +
1.649 +/*
1.650 +** CAPI3REF: Device Characteristics
1.651 +**
1.652 +** The xDeviceCharacteristics method of the [sqlite3_io_methods]
1.653 +** object returns an integer which is a vector of these
1.654 +** bit values expressing I/O characteristics of the mass storage
1.655 +** device that holds the file that the [sqlite3_io_methods]
1.656 +** refers to.
1.657 +**
1.658 +** The SQLITE_IOCAP_ATOMIC property means that all writes of
1.659 +** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
1.660 +** mean that writes of blocks that are nnn bytes in size and
1.661 +** are aligned to an address which is an integer multiple of
1.662 +** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
1.663 +** that when data is appended to a file, the data is appended
1.664 +** first then the size of the file is extended, never the other
1.665 +** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
1.666 +** information is written to disk in the same order as calls
1.667 +** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
1.668 +** after reboot following a crash or power loss, the only bytes in a
1.669 +** file that were written at the application level might have changed
1.670 +** and that adjacent bytes, even bytes within the same sector are
1.671 +** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
1.672 +** flag indicate that a file cannot be deleted when open. The
1.673 +** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
1.674 +** read-only media and cannot be changed even by processes with
1.675 +** elevated privileges.
1.676 +*/
1.677 +#define SQLITE_IOCAP_ATOMIC 0x00000001
1.678 +#define SQLITE_IOCAP_ATOMIC512 0x00000002
1.679 +#define SQLITE_IOCAP_ATOMIC1K 0x00000004
1.680 +#define SQLITE_IOCAP_ATOMIC2K 0x00000008
1.681 +#define SQLITE_IOCAP_ATOMIC4K 0x00000010
1.682 +#define SQLITE_IOCAP_ATOMIC8K 0x00000020
1.683 +#define SQLITE_IOCAP_ATOMIC16K 0x00000040
1.684 +#define SQLITE_IOCAP_ATOMIC32K 0x00000080
1.685 +#define SQLITE_IOCAP_ATOMIC64K 0x00000100
1.686 +#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
1.687 +#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
1.688 +#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
1.689 +#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
1.690 +#define SQLITE_IOCAP_IMMUTABLE 0x00002000
1.691 +
1.692 +/*
1.693 +** CAPI3REF: File Locking Levels
1.694 +**
1.695 +** SQLite uses one of these integer values as the second
1.696 +** argument to calls it makes to the xLock() and xUnlock() methods
1.697 +** of an [sqlite3_io_methods] object.
1.698 +*/
1.699 +#define SQLITE_LOCK_NONE 0
1.700 +#define SQLITE_LOCK_SHARED 1
1.701 +#define SQLITE_LOCK_RESERVED 2
1.702 +#define SQLITE_LOCK_PENDING 3
1.703 +#define SQLITE_LOCK_EXCLUSIVE 4
1.704 +
1.705 +/*
1.706 +** CAPI3REF: Synchronization Type Flags
1.707 +**
1.708 +** When SQLite invokes the xSync() method of an
1.709 +** [sqlite3_io_methods] object it uses a combination of
1.710 +** these integer values as the second argument.
1.711 +**
1.712 +** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
1.713 +** sync operation only needs to flush data to mass storage. Inode
1.714 +** information need not be flushed. If the lower four bits of the flag
1.715 +** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
1.716 +** If the lower four bits equal SQLITE_SYNC_FULL, that means
1.717 +** to use Mac OS X style fullsync instead of fsync().
1.718 +**
1.719 +** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
1.720 +** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
1.721 +** settings. The [synchronous pragma] determines when calls to the
1.722 +** xSync VFS method occur and applies uniformly across all platforms.
1.723 +** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
1.724 +** energetic or rigorous or forceful the sync operations are and
1.725 +** only make a difference on Mac OSX for the default SQLite code.
1.726 +** (Third-party VFS implementations might also make the distinction
1.727 +** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
1.728 +** operating systems natively supported by SQLite, only Mac OSX
1.729 +** cares about the difference.)
1.730 +*/
1.731 +#define SQLITE_SYNC_NORMAL 0x00002
1.732 +#define SQLITE_SYNC_FULL 0x00003
1.733 +#define SQLITE_SYNC_DATAONLY 0x00010
1.734 +
1.735 +/*
1.736 +** CAPI3REF: OS Interface Open File Handle
1.737 +**
1.738 +** An [sqlite3_file] object represents an open file in the
1.739 +** [sqlite3_vfs | OS interface layer]. Individual OS interface
1.740 +** implementations will
1.741 +** want to subclass this object by appending additional fields
1.742 +** for their own use. The pMethods entry is a pointer to an
1.743 +** [sqlite3_io_methods] object that defines methods for performing
1.744 +** I/O operations on the open file.
1.745 +*/
1.746 +typedef struct sqlite3_file sqlite3_file;
1.747 +struct sqlite3_file {
1.748 + const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
1.749 +};
1.750 +
1.751 +/*
1.752 +** CAPI3REF: OS Interface File Virtual Methods Object
1.753 +**
1.754 +** Every file opened by the [sqlite3_vfs.xOpen] method populates an
1.755 +** [sqlite3_file] object (or, more commonly, a subclass of the
1.756 +** [sqlite3_file] object) with a pointer to an instance of this object.
1.757 +** This object defines the methods used to perform various operations
1.758 +** against the open file represented by the [sqlite3_file] object.
1.759 +**
1.760 +** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
1.761 +** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
1.762 +** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
1.763 +** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
1.764 +** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
1.765 +** to NULL.
1.766 +**
1.767 +** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
1.768 +** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
1.769 +** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
1.770 +** flag may be ORed in to indicate that only the data of the file
1.771 +** and not its inode needs to be synced.
1.772 +**
1.773 +** The integer values to xLock() and xUnlock() are one of
1.774 +** <ul>
1.775 +** <li> [SQLITE_LOCK_NONE],
1.776 +** <li> [SQLITE_LOCK_SHARED],
1.777 +** <li> [SQLITE_LOCK_RESERVED],
1.778 +** <li> [SQLITE_LOCK_PENDING], or
1.779 +** <li> [SQLITE_LOCK_EXCLUSIVE].
1.780 +** </ul>
1.781 +** xLock() increases the lock. xUnlock() decreases the lock.
1.782 +** The xCheckReservedLock() method checks whether any database connection,
1.783 +** either in this process or in some other process, is holding a RESERVED,
1.784 +** PENDING, or EXCLUSIVE lock on the file. It returns true
1.785 +** if such a lock exists and false otherwise.
1.786 +**
1.787 +** The xFileControl() method is a generic interface that allows custom
1.788 +** VFS implementations to directly control an open file using the
1.789 +** [sqlite3_file_control()] interface. The second "op" argument is an
1.790 +** integer opcode. The third argument is a generic pointer intended to
1.791 +** point to a structure that may contain arguments or space in which to
1.792 +** write return values. Potential uses for xFileControl() might be
1.793 +** functions to enable blocking locks with timeouts, to change the
1.794 +** locking strategy (for example to use dot-file locks), to inquire
1.795 +** about the status of a lock, or to break stale locks. The SQLite
1.796 +** core reserves all opcodes less than 100 for its own use.
1.797 +** A [file control opcodes | list of opcodes] less than 100 is available.
1.798 +** Applications that define a custom xFileControl method should use opcodes
1.799 +** greater than 100 to avoid conflicts. VFS implementations should
1.800 +** return [SQLITE_NOTFOUND] for file control opcodes that they do not
1.801 +** recognize.
1.802 +**
1.803 +** The xSectorSize() method returns the sector size of the
1.804 +** device that underlies the file. The sector size is the
1.805 +** minimum write that can be performed without disturbing
1.806 +** other bytes in the file. The xDeviceCharacteristics()
1.807 +** method returns a bit vector describing behaviors of the
1.808 +** underlying device:
1.809 +**
1.810 +** <ul>
1.811 +** <li> [SQLITE_IOCAP_ATOMIC]
1.812 +** <li> [SQLITE_IOCAP_ATOMIC512]
1.813 +** <li> [SQLITE_IOCAP_ATOMIC1K]
1.814 +** <li> [SQLITE_IOCAP_ATOMIC2K]
1.815 +** <li> [SQLITE_IOCAP_ATOMIC4K]
1.816 +** <li> [SQLITE_IOCAP_ATOMIC8K]
1.817 +** <li> [SQLITE_IOCAP_ATOMIC16K]
1.818 +** <li> [SQLITE_IOCAP_ATOMIC32K]
1.819 +** <li> [SQLITE_IOCAP_ATOMIC64K]
1.820 +** <li> [SQLITE_IOCAP_SAFE_APPEND]
1.821 +** <li> [SQLITE_IOCAP_SEQUENTIAL]
1.822 +** </ul>
1.823 +**
1.824 +** The SQLITE_IOCAP_ATOMIC property means that all writes of
1.825 +** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
1.826 +** mean that writes of blocks that are nnn bytes in size and
1.827 +** are aligned to an address which is an integer multiple of
1.828 +** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
1.829 +** that when data is appended to a file, the data is appended
1.830 +** first then the size of the file is extended, never the other
1.831 +** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
1.832 +** information is written to disk in the same order as calls
1.833 +** to xWrite().
1.834 +**
1.835 +** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
1.836 +** in the unread portions of the buffer with zeros. A VFS that
1.837 +** fails to zero-fill short reads might seem to work. However,
1.838 +** failure to zero-fill short reads will eventually lead to
1.839 +** database corruption.
1.840 +*/
1.841 +typedef struct sqlite3_io_methods sqlite3_io_methods;
1.842 +struct sqlite3_io_methods {
1.843 + int iVersion;
1.844 + int (*xClose)(sqlite3_file*);
1.845 + int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
1.846 + int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
1.847 + int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
1.848 + int (*xSync)(sqlite3_file*, int flags);
1.849 + int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
1.850 + int (*xLock)(sqlite3_file*, int);
1.851 + int (*xUnlock)(sqlite3_file*, int);
1.852 + int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
1.853 + int (*xFileControl)(sqlite3_file*, int op, void *pArg);
1.854 + int (*xSectorSize)(sqlite3_file*);
1.855 + int (*xDeviceCharacteristics)(sqlite3_file*);
1.856 + /* Methods above are valid for version 1 */
1.857 + int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
1.858 + int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
1.859 + void (*xShmBarrier)(sqlite3_file*);
1.860 + int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
1.861 + /* Methods above are valid for version 2 */
1.862 + int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
1.863 + int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
1.864 + /* Methods above are valid for version 3 */
1.865 + /* Additional methods may be added in future releases */
1.866 +};
1.867 +
1.868 +/*
1.869 +** CAPI3REF: Standard File Control Opcodes
1.870 +** KEYWORDS: {file control opcodes} {file control opcode}
1.871 +**
1.872 +** These integer constants are opcodes for the xFileControl method
1.873 +** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
1.874 +** interface.
1.875 +**
1.876 +** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
1.877 +** opcode causes the xFileControl method to write the current state of
1.878 +** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
1.879 +** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
1.880 +** into an integer that the pArg argument points to. This capability
1.881 +** is used during testing and only needs to be supported when SQLITE_TEST
1.882 +** is defined.
1.883 +** <ul>
1.884 +** <li>[[SQLITE_FCNTL_SIZE_HINT]]
1.885 +** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
1.886 +** layer a hint of how large the database file will grow to be during the
1.887 +** current transaction. This hint is not guaranteed to be accurate but it
1.888 +** is often close. The underlying VFS might choose to preallocate database
1.889 +** file space based on this hint in order to help writes to the database
1.890 +** file run faster.
1.891 +**
1.892 +** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
1.893 +** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
1.894 +** extends and truncates the database file in chunks of a size specified
1.895 +** by the user. The fourth argument to [sqlite3_file_control()] should
1.896 +** point to an integer (type int) containing the new chunk-size to use
1.897 +** for the nominated database. Allocating database file space in large
1.898 +** chunks (say 1MB at a time), may reduce file-system fragmentation and
1.899 +** improve performance on some systems.
1.900 +**
1.901 +** <li>[[SQLITE_FCNTL_FILE_POINTER]]
1.902 +** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
1.903 +** to the [sqlite3_file] object associated with a particular database
1.904 +** connection. See the [sqlite3_file_control()] documentation for
1.905 +** additional information.
1.906 +**
1.907 +** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
1.908 +** No longer in use.
1.909 +**
1.910 +** <li>[[SQLITE_FCNTL_SYNC]]
1.911 +** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
1.912 +** sent to the VFS immediately before the xSync method is invoked on a
1.913 +** database file descriptor. Or, if the xSync method is not invoked
1.914 +** because the user has configured SQLite with
1.915 +** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
1.916 +** of the xSync method. In most cases, the pointer argument passed with
1.917 +** this file-control is NULL. However, if the database file is being synced
1.918 +** as part of a multi-database commit, the argument points to a nul-terminated
1.919 +** string containing the transactions master-journal file name. VFSes that
1.920 +** do not need this signal should silently ignore this opcode. Applications
1.921 +** should not call [sqlite3_file_control()] with this opcode as doing so may
1.922 +** disrupt the operation of the specialized VFSes that do require it.
1.923 +**
1.924 +** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
1.925 +** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
1.926 +** and sent to the VFS after a transaction has been committed immediately
1.927 +** but before the database is unlocked. VFSes that do not need this signal
1.928 +** should silently ignore this opcode. Applications should not call
1.929 +** [sqlite3_file_control()] with this opcode as doing so may disrupt the
1.930 +** operation of the specialized VFSes that do require it.
1.931 +**
1.932 +** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
1.933 +** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
1.934 +** retry counts and intervals for certain disk I/O operations for the
1.935 +** windows [VFS] in order to provide robustness in the presence of
1.936 +** anti-virus programs. By default, the windows VFS will retry file read,
1.937 +** file write, and file delete operations up to 10 times, with a delay
1.938 +** of 25 milliseconds before the first retry and with the delay increasing
1.939 +** by an additional 25 milliseconds with each subsequent retry. This
1.940 +** opcode allows these two values (10 retries and 25 milliseconds of delay)
1.941 +** to be adjusted. The values are changed for all database connections
1.942 +** within the same process. The argument is a pointer to an array of two
1.943 +** integers where the first integer i the new retry count and the second
1.944 +** integer is the delay. If either integer is negative, then the setting
1.945 +** is not changed but instead the prior value of that setting is written
1.946 +** into the array entry, allowing the current retry settings to be
1.947 +** interrogated. The zDbName parameter is ignored.
1.948 +**
1.949 +** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
1.950 +** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
1.951 +** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
1.952 +** write ahead log and shared memory files used for transaction control
1.953 +** are automatically deleted when the latest connection to the database
1.954 +** closes. Setting persistent WAL mode causes those files to persist after
1.955 +** close. Persisting the files is useful when other processes that do not
1.956 +** have write permission on the directory containing the database file want
1.957 +** to read the database file, as the WAL and shared memory files must exist
1.958 +** in order for the database to be readable. The fourth parameter to
1.959 +** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
1.960 +** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
1.961 +** WAL mode. If the integer is -1, then it is overwritten with the current
1.962 +** WAL persistence setting.
1.963 +**
1.964 +** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
1.965 +** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
1.966 +** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
1.967 +** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
1.968 +** xDeviceCharacteristics methods. The fourth parameter to
1.969 +** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
1.970 +** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
1.971 +** mode. If the integer is -1, then it is overwritten with the current
1.972 +** zero-damage mode setting.
1.973 +**
1.974 +** <li>[[SQLITE_FCNTL_OVERWRITE]]
1.975 +** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
1.976 +** a write transaction to indicate that, unless it is rolled back for some
1.977 +** reason, the entire database file will be overwritten by the current
1.978 +** transaction. This is used by VACUUM operations.
1.979 +**
1.980 +** <li>[[SQLITE_FCNTL_VFSNAME]]
1.981 +** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
1.982 +** all [VFSes] in the VFS stack. The names are of all VFS shims and the
1.983 +** final bottom-level VFS are written into memory obtained from
1.984 +** [sqlite3_malloc()] and the result is stored in the char* variable
1.985 +** that the fourth parameter of [sqlite3_file_control()] points to.
1.986 +** The caller is responsible for freeing the memory when done. As with
1.987 +** all file-control actions, there is no guarantee that this will actually
1.988 +** do anything. Callers should initialize the char* variable to a NULL
1.989 +** pointer in case this file-control is not implemented. This file-control
1.990 +** is intended for diagnostic use only.
1.991 +**
1.992 +** <li>[[SQLITE_FCNTL_PRAGMA]]
1.993 +** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1.994 +** file control is sent to the open [sqlite3_file] object corresponding
1.995 +** to the database file to which the pragma statement refers. ^The argument
1.996 +** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1.997 +** pointers to strings (char**) in which the second element of the array
1.998 +** is the name of the pragma and the third element is the argument to the
1.999 +** pragma or NULL if the pragma has no argument. ^The handler for an
1.1000 +** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1.1001 +** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1.1002 +** or the equivalent and that string will become the result of the pragma or
1.1003 +** the error message if the pragma fails. ^If the
1.1004 +** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1.1005 +** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
1.1006 +** file control returns [SQLITE_OK], then the parser assumes that the
1.1007 +** VFS has handled the PRAGMA itself and the parser generates a no-op
1.1008 +** prepared statement. ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1.1009 +** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1.1010 +** that the VFS encountered an error while handling the [PRAGMA] and the
1.1011 +** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
1.1012 +** file control occurs at the beginning of pragma statement analysis and so
1.1013 +** it is able to override built-in [PRAGMA] statements.
1.1014 +**
1.1015 +** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1.1016 +** ^The [SQLITE_FCNTL_BUSYHANDLER]
1.1017 +** file-control may be invoked by SQLite on the database file handle
1.1018 +** shortly after it is opened in order to provide a custom VFS with access
1.1019 +** to the connections busy-handler callback. The argument is of type (void **)
1.1020 +** - an array of two (void *) values. The first (void *) actually points
1.1021 +** to a function of type (int (*)(void *)). In order to invoke the connections
1.1022 +** busy-handler, this function should be invoked with the second (void *) in
1.1023 +** the array as the only argument. If it returns non-zero, then the operation
1.1024 +** should be retried. If it returns zero, the custom VFS should abandon the
1.1025 +** current operation.
1.1026 +**
1.1027 +** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1.1028 +** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1.1029 +** to have SQLite generate a
1.1030 +** temporary filename using the same algorithm that is followed to generate
1.1031 +** temporary filenames for TEMP tables and other internal uses. The
1.1032 +** argument should be a char** which will be filled with the filename
1.1033 +** written into memory obtained from [sqlite3_malloc()]. The caller should
1.1034 +** invoke [sqlite3_free()] on the result to avoid a memory leak.
1.1035 +**
1.1036 +** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1.1037 +** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1.1038 +** maximum number of bytes that will be used for memory-mapped I/O.
1.1039 +** The argument is a pointer to a value of type sqlite3_int64 that
1.1040 +** is an advisory maximum number of bytes in the file to memory map. The
1.1041 +** pointer is overwritten with the old value. The limit is not changed if
1.1042 +** the value originally pointed to is negative, and so the current limit
1.1043 +** can be queried by passing in a pointer to a negative number. This
1.1044 +** file-control is used internally to implement [PRAGMA mmap_size].
1.1045 +**
1.1046 +** <li>[[SQLITE_FCNTL_TRACE]]
1.1047 +** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1.1048 +** to the VFS about what the higher layers of the SQLite stack are doing.
1.1049 +** This file control is used by some VFS activity tracing [shims].
1.1050 +** The argument is a zero-terminated string. Higher layers in the
1.1051 +** SQLite stack may generate instances of this file control if
1.1052 +** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1.1053 +**
1.1054 +** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1.1055 +** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1.1056 +** pointer to an integer and it writes a boolean into that integer depending
1.1057 +** on whether or not the file has been renamed, moved, or deleted since it
1.1058 +** was first opened.
1.1059 +**
1.1060 +** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1.1061 +** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This
1.1062 +** opcode causes the xFileControl method to swap the file handle with the one
1.1063 +** pointed to by the pArg argument. This capability is used during testing
1.1064 +** and only needs to be supported when SQLITE_TEST is defined.
1.1065 +**
1.1066 +** </ul>
1.1067 +*/
1.1068 +#define SQLITE_FCNTL_LOCKSTATE 1
1.1069 +#define SQLITE_GET_LOCKPROXYFILE 2
1.1070 +#define SQLITE_SET_LOCKPROXYFILE 3
1.1071 +#define SQLITE_LAST_ERRNO 4
1.1072 +#define SQLITE_FCNTL_SIZE_HINT 5
1.1073 +#define SQLITE_FCNTL_CHUNK_SIZE 6
1.1074 +#define SQLITE_FCNTL_FILE_POINTER 7
1.1075 +#define SQLITE_FCNTL_SYNC_OMITTED 8
1.1076 +#define SQLITE_FCNTL_WIN32_AV_RETRY 9
1.1077 +#define SQLITE_FCNTL_PERSIST_WAL 10
1.1078 +#define SQLITE_FCNTL_OVERWRITE 11
1.1079 +#define SQLITE_FCNTL_VFSNAME 12
1.1080 +#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
1.1081 +#define SQLITE_FCNTL_PRAGMA 14
1.1082 +#define SQLITE_FCNTL_BUSYHANDLER 15
1.1083 +#define SQLITE_FCNTL_TEMPFILENAME 16
1.1084 +#define SQLITE_FCNTL_MMAP_SIZE 18
1.1085 +#define SQLITE_FCNTL_TRACE 19
1.1086 +#define SQLITE_FCNTL_HAS_MOVED 20
1.1087 +#define SQLITE_FCNTL_SYNC 21
1.1088 +#define SQLITE_FCNTL_COMMIT_PHASETWO 22
1.1089 +#define SQLITE_FCNTL_WIN32_SET_HANDLE 23
1.1090 +
1.1091 +/*
1.1092 +** CAPI3REF: Mutex Handle
1.1093 +**
1.1094 +** The mutex module within SQLite defines [sqlite3_mutex] to be an
1.1095 +** abstract type for a mutex object. The SQLite core never looks
1.1096 +** at the internal representation of an [sqlite3_mutex]. It only
1.1097 +** deals with pointers to the [sqlite3_mutex] object.
1.1098 +**
1.1099 +** Mutexes are created using [sqlite3_mutex_alloc()].
1.1100 +*/
1.1101 +typedef struct sqlite3_mutex sqlite3_mutex;
1.1102 +
1.1103 +/*
1.1104 +** CAPI3REF: OS Interface Object
1.1105 +**
1.1106 +** An instance of the sqlite3_vfs object defines the interface between
1.1107 +** the SQLite core and the underlying operating system. The "vfs"
1.1108 +** in the name of the object stands for "virtual file system". See
1.1109 +** the [VFS | VFS documentation] for further information.
1.1110 +**
1.1111 +** The value of the iVersion field is initially 1 but may be larger in
1.1112 +** future versions of SQLite. Additional fields may be appended to this
1.1113 +** object when the iVersion value is increased. Note that the structure
1.1114 +** of the sqlite3_vfs object changes in the transaction between
1.1115 +** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
1.1116 +** modified.
1.1117 +**
1.1118 +** The szOsFile field is the size of the subclassed [sqlite3_file]
1.1119 +** structure used by this VFS. mxPathname is the maximum length of
1.1120 +** a pathname in this VFS.
1.1121 +**
1.1122 +** Registered sqlite3_vfs objects are kept on a linked list formed by
1.1123 +** the pNext pointer. The [sqlite3_vfs_register()]
1.1124 +** and [sqlite3_vfs_unregister()] interfaces manage this list
1.1125 +** in a thread-safe way. The [sqlite3_vfs_find()] interface
1.1126 +** searches the list. Neither the application code nor the VFS
1.1127 +** implementation should use the pNext pointer.
1.1128 +**
1.1129 +** The pNext field is the only field in the sqlite3_vfs
1.1130 +** structure that SQLite will ever modify. SQLite will only access
1.1131 +** or modify this field while holding a particular static mutex.
1.1132 +** The application should never modify anything within the sqlite3_vfs
1.1133 +** object once the object has been registered.
1.1134 +**
1.1135 +** The zName field holds the name of the VFS module. The name must
1.1136 +** be unique across all VFS modules.
1.1137 +**
1.1138 +** [[sqlite3_vfs.xOpen]]
1.1139 +** ^SQLite guarantees that the zFilename parameter to xOpen
1.1140 +** is either a NULL pointer or string obtained
1.1141 +** from xFullPathname() with an optional suffix added.
1.1142 +** ^If a suffix is added to the zFilename parameter, it will
1.1143 +** consist of a single "-" character followed by no more than
1.1144 +** 11 alphanumeric and/or "-" characters.
1.1145 +** ^SQLite further guarantees that
1.1146 +** the string will be valid and unchanged until xClose() is
1.1147 +** called. Because of the previous sentence,
1.1148 +** the [sqlite3_file] can safely store a pointer to the
1.1149 +** filename if it needs to remember the filename for some reason.
1.1150 +** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1.1151 +** must invent its own temporary name for the file. ^Whenever the
1.1152 +** xFilename parameter is NULL it will also be the case that the
1.1153 +** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1.1154 +**
1.1155 +** The flags argument to xOpen() includes all bits set in
1.1156 +** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
1.1157 +** or [sqlite3_open16()] is used, then flags includes at least
1.1158 +** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1.1159 +** If xOpen() opens a file read-only then it sets *pOutFlags to
1.1160 +** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
1.1161 +**
1.1162 +** ^(SQLite will also add one of the following flags to the xOpen()
1.1163 +** call, depending on the object being opened:
1.1164 +**
1.1165 +** <ul>
1.1166 +** <li> [SQLITE_OPEN_MAIN_DB]
1.1167 +** <li> [SQLITE_OPEN_MAIN_JOURNAL]
1.1168 +** <li> [SQLITE_OPEN_TEMP_DB]
1.1169 +** <li> [SQLITE_OPEN_TEMP_JOURNAL]
1.1170 +** <li> [SQLITE_OPEN_TRANSIENT_DB]
1.1171 +** <li> [SQLITE_OPEN_SUBJOURNAL]
1.1172 +** <li> [SQLITE_OPEN_MASTER_JOURNAL]
1.1173 +** <li> [SQLITE_OPEN_WAL]
1.1174 +** </ul>)^
1.1175 +**
1.1176 +** The file I/O implementation can use the object type flags to
1.1177 +** change the way it deals with files. For example, an application
1.1178 +** that does not care about crash recovery or rollback might make
1.1179 +** the open of a journal file a no-op. Writes to this journal would
1.1180 +** also be no-ops, and any attempt to read the journal would return
1.1181 +** SQLITE_IOERR. Or the implementation might recognize that a database
1.1182 +** file will be doing page-aligned sector reads and writes in a random
1.1183 +** order and set up its I/O subsystem accordingly.
1.1184 +**
1.1185 +** SQLite might also add one of the following flags to the xOpen method:
1.1186 +**
1.1187 +** <ul>
1.1188 +** <li> [SQLITE_OPEN_DELETEONCLOSE]
1.1189 +** <li> [SQLITE_OPEN_EXCLUSIVE]
1.1190 +** </ul>
1.1191 +**
1.1192 +** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1.1193 +** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
1.1194 +** will be set for TEMP databases and their journals, transient
1.1195 +** databases, and subjournals.
1.1196 +**
1.1197 +** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1.1198 +** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1.1199 +** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1.1200 +** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1.1201 +** SQLITE_OPEN_CREATE, is used to indicate that file should always
1.1202 +** be created, and that it is an error if it already exists.
1.1203 +** It is <i>not</i> used to indicate the file should be opened
1.1204 +** for exclusive access.
1.1205 +**
1.1206 +** ^At least szOsFile bytes of memory are allocated by SQLite
1.1207 +** to hold the [sqlite3_file] structure passed as the third
1.1208 +** argument to xOpen. The xOpen method does not have to
1.1209 +** allocate the structure; it should just fill it in. Note that
1.1210 +** the xOpen method must set the sqlite3_file.pMethods to either
1.1211 +** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
1.1212 +** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
1.1213 +** element will be valid after xOpen returns regardless of the success
1.1214 +** or failure of the xOpen call.
1.1215 +**
1.1216 +** [[sqlite3_vfs.xAccess]]
1.1217 +** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1.1218 +** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1.1219 +** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1.1220 +** to test whether a file is at least readable. The file can be a
1.1221 +** directory.
1.1222 +**
1.1223 +** ^SQLite will always allocate at least mxPathname+1 bytes for the
1.1224 +** output buffer xFullPathname. The exact size of the output buffer
1.1225 +** is also passed as a parameter to both methods. If the output buffer
1.1226 +** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1.1227 +** handled as a fatal error by SQLite, vfs implementations should endeavor
1.1228 +** to prevent this by setting mxPathname to a sufficiently large value.
1.1229 +**
1.1230 +** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1.1231 +** interfaces are not strictly a part of the filesystem, but they are
1.1232 +** included in the VFS structure for completeness.
1.1233 +** The xRandomness() function attempts to return nBytes bytes
1.1234 +** of good-quality randomness into zOut. The return value is
1.1235 +** the actual number of bytes of randomness obtained.
1.1236 +** The xSleep() method causes the calling thread to sleep for at
1.1237 +** least the number of microseconds given. ^The xCurrentTime()
1.1238 +** method returns a Julian Day Number for the current date and time as
1.1239 +** a floating point value.
1.1240 +** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1.1241 +** Day Number multiplied by 86400000 (the number of milliseconds in
1.1242 +** a 24-hour day).
1.1243 +** ^SQLite will use the xCurrentTimeInt64() method to get the current
1.1244 +** date and time if that method is available (if iVersion is 2 or
1.1245 +** greater and the function pointer is not NULL) and will fall back
1.1246 +** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1.1247 +**
1.1248 +** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1.1249 +** are not used by the SQLite core. These optional interfaces are provided
1.1250 +** by some VFSes to facilitate testing of the VFS code. By overriding
1.1251 +** system calls with functions under its control, a test program can
1.1252 +** simulate faults and error conditions that would otherwise be difficult
1.1253 +** or impossible to induce. The set of system calls that can be overridden
1.1254 +** varies from one VFS to another, and from one version of the same VFS to the
1.1255 +** next. Applications that use these interfaces must be prepared for any
1.1256 +** or all of these interfaces to be NULL or for their behavior to change
1.1257 +** from one release to the next. Applications must not attempt to access
1.1258 +** any of these methods if the iVersion of the VFS is less than 3.
1.1259 +*/
1.1260 +typedef struct sqlite3_vfs sqlite3_vfs;
1.1261 +typedef void (*sqlite3_syscall_ptr)(void);
1.1262 +struct sqlite3_vfs {
1.1263 + int iVersion; /* Structure version number (currently 3) */
1.1264 + int szOsFile; /* Size of subclassed sqlite3_file */
1.1265 + int mxPathname; /* Maximum file pathname length */
1.1266 + sqlite3_vfs *pNext; /* Next registered VFS */
1.1267 + const char *zName; /* Name of this virtual file system */
1.1268 + void *pAppData; /* Pointer to application-specific data */
1.1269 + int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1.1270 + int flags, int *pOutFlags);
1.1271 + int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1.1272 + int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1.1273 + int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1.1274 + void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1.1275 + void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1.1276 + void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1.1277 + void (*xDlClose)(sqlite3_vfs*, void*);
1.1278 + int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1.1279 + int (*xSleep)(sqlite3_vfs*, int microseconds);
1.1280 + int (*xCurrentTime)(sqlite3_vfs*, double*);
1.1281 + int (*xGetLastError)(sqlite3_vfs*, int, char *);
1.1282 + /*
1.1283 + ** The methods above are in version 1 of the sqlite_vfs object
1.1284 + ** definition. Those that follow are added in version 2 or later
1.1285 + */
1.1286 + int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1.1287 + /*
1.1288 + ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1.1289 + ** Those below are for version 3 and greater.
1.1290 + */
1.1291 + int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1.1292 + sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1.1293 + const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1.1294 + /*
1.1295 + ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1.1296 + ** New fields may be appended in figure versions. The iVersion
1.1297 + ** value will increment whenever this happens.
1.1298 + */
1.1299 +};
1.1300 +
1.1301 +/*
1.1302 +** CAPI3REF: Flags for the xAccess VFS method
1.1303 +**
1.1304 +** These integer constants can be used as the third parameter to
1.1305 +** the xAccess method of an [sqlite3_vfs] object. They determine
1.1306 +** what kind of permissions the xAccess method is looking for.
1.1307 +** With SQLITE_ACCESS_EXISTS, the xAccess method
1.1308 +** simply checks whether the file exists.
1.1309 +** With SQLITE_ACCESS_READWRITE, the xAccess method
1.1310 +** checks whether the named directory is both readable and writable
1.1311 +** (in other words, if files can be added, removed, and renamed within
1.1312 +** the directory).
1.1313 +** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1.1314 +** [temp_store_directory pragma], though this could change in a future
1.1315 +** release of SQLite.
1.1316 +** With SQLITE_ACCESS_READ, the xAccess method
1.1317 +** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
1.1318 +** currently unused, though it might be used in a future release of
1.1319 +** SQLite.
1.1320 +*/
1.1321 +#define SQLITE_ACCESS_EXISTS 0
1.1322 +#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
1.1323 +#define SQLITE_ACCESS_READ 2 /* Unused */
1.1324 +
1.1325 +/*
1.1326 +** CAPI3REF: Flags for the xShmLock VFS method
1.1327 +**
1.1328 +** These integer constants define the various locking operations
1.1329 +** allowed by the xShmLock method of [sqlite3_io_methods]. The
1.1330 +** following are the only legal combinations of flags to the
1.1331 +** xShmLock method:
1.1332 +**
1.1333 +** <ul>
1.1334 +** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1.1335 +** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1.1336 +** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1.1337 +** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1.1338 +** </ul>
1.1339 +**
1.1340 +** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1.1341 +** was given no the corresponding lock.
1.1342 +**
1.1343 +** The xShmLock method can transition between unlocked and SHARED or
1.1344 +** between unlocked and EXCLUSIVE. It cannot transition between SHARED
1.1345 +** and EXCLUSIVE.
1.1346 +*/
1.1347 +#define SQLITE_SHM_UNLOCK 1
1.1348 +#define SQLITE_SHM_LOCK 2
1.1349 +#define SQLITE_SHM_SHARED 4
1.1350 +#define SQLITE_SHM_EXCLUSIVE 8
1.1351 +
1.1352 +/*
1.1353 +** CAPI3REF: Maximum xShmLock index
1.1354 +**
1.1355 +** The xShmLock method on [sqlite3_io_methods] may use values
1.1356 +** between 0 and this upper bound as its "offset" argument.
1.1357 +** The SQLite core will never attempt to acquire or release a
1.1358 +** lock outside of this range
1.1359 +*/
1.1360 +#define SQLITE_SHM_NLOCK 8
1.1361 +
1.1362 +
1.1363 +/*
1.1364 +** CAPI3REF: Initialize The SQLite Library
1.1365 +**
1.1366 +** ^The sqlite3_initialize() routine initializes the
1.1367 +** SQLite library. ^The sqlite3_shutdown() routine
1.1368 +** deallocates any resources that were allocated by sqlite3_initialize().
1.1369 +** These routines are designed to aid in process initialization and
1.1370 +** shutdown on embedded systems. Workstation applications using
1.1371 +** SQLite normally do not need to invoke either of these routines.
1.1372 +**
1.1373 +** A call to sqlite3_initialize() is an "effective" call if it is
1.1374 +** the first time sqlite3_initialize() is invoked during the lifetime of
1.1375 +** the process, or if it is the first time sqlite3_initialize() is invoked
1.1376 +** following a call to sqlite3_shutdown(). ^(Only an effective call
1.1377 +** of sqlite3_initialize() does any initialization. All other calls
1.1378 +** are harmless no-ops.)^
1.1379 +**
1.1380 +** A call to sqlite3_shutdown() is an "effective" call if it is the first
1.1381 +** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
1.1382 +** an effective call to sqlite3_shutdown() does any deinitialization.
1.1383 +** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1.1384 +**
1.1385 +** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1.1386 +** is not. The sqlite3_shutdown() interface must only be called from a
1.1387 +** single thread. All open [database connections] must be closed and all
1.1388 +** other SQLite resources must be deallocated prior to invoking
1.1389 +** sqlite3_shutdown().
1.1390 +**
1.1391 +** Among other things, ^sqlite3_initialize() will invoke
1.1392 +** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
1.1393 +** will invoke sqlite3_os_end().
1.1394 +**
1.1395 +** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1.1396 +** ^If for some reason, sqlite3_initialize() is unable to initialize
1.1397 +** the library (perhaps it is unable to allocate a needed resource such
1.1398 +** as a mutex) it returns an [error code] other than [SQLITE_OK].
1.1399 +**
1.1400 +** ^The sqlite3_initialize() routine is called internally by many other
1.1401 +** SQLite interfaces so that an application usually does not need to
1.1402 +** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
1.1403 +** calls sqlite3_initialize() so the SQLite library will be automatically
1.1404 +** initialized when [sqlite3_open()] is called if it has not be initialized
1.1405 +** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1.1406 +** compile-time option, then the automatic calls to sqlite3_initialize()
1.1407 +** are omitted and the application must call sqlite3_initialize() directly
1.1408 +** prior to using any other SQLite interface. For maximum portability,
1.1409 +** it is recommended that applications always invoke sqlite3_initialize()
1.1410 +** directly prior to using any other SQLite interface. Future releases
1.1411 +** of SQLite may require this. In other words, the behavior exhibited
1.1412 +** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1.1413 +** default behavior in some future release of SQLite.
1.1414 +**
1.1415 +** The sqlite3_os_init() routine does operating-system specific
1.1416 +** initialization of the SQLite library. The sqlite3_os_end()
1.1417 +** routine undoes the effect of sqlite3_os_init(). Typical tasks
1.1418 +** performed by these routines include allocation or deallocation
1.1419 +** of static resources, initialization of global variables,
1.1420 +** setting up a default [sqlite3_vfs] module, or setting up
1.1421 +** a default configuration using [sqlite3_config()].
1.1422 +**
1.1423 +** The application should never invoke either sqlite3_os_init()
1.1424 +** or sqlite3_os_end() directly. The application should only invoke
1.1425 +** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
1.1426 +** interface is called automatically by sqlite3_initialize() and
1.1427 +** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
1.1428 +** implementations for sqlite3_os_init() and sqlite3_os_end()
1.1429 +** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1.1430 +** When [custom builds | built for other platforms]
1.1431 +** (using the [SQLITE_OS_OTHER=1] compile-time
1.1432 +** option) the application must supply a suitable implementation for
1.1433 +** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
1.1434 +** implementation of sqlite3_os_init() or sqlite3_os_end()
1.1435 +** must return [SQLITE_OK] on success and some other [error code] upon
1.1436 +** failure.
1.1437 +*/
1.1438 +SQLITE_API int sqlite3_initialize(void);
1.1439 +SQLITE_API int sqlite3_shutdown(void);
1.1440 +SQLITE_API int sqlite3_os_init(void);
1.1441 +SQLITE_API int sqlite3_os_end(void);
1.1442 +
1.1443 +/*
1.1444 +** CAPI3REF: Configuring The SQLite Library
1.1445 +**
1.1446 +** The sqlite3_config() interface is used to make global configuration
1.1447 +** changes to SQLite in order to tune SQLite to the specific needs of
1.1448 +** the application. The default configuration is recommended for most
1.1449 +** applications and so this routine is usually not necessary. It is
1.1450 +** provided to support rare applications with unusual needs.
1.1451 +**
1.1452 +** The sqlite3_config() interface is not threadsafe. The application
1.1453 +** must insure that no other SQLite interfaces are invoked by other
1.1454 +** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
1.1455 +** may only be invoked prior to library initialization using
1.1456 +** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1.1457 +** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1.1458 +** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1.1459 +** Note, however, that ^sqlite3_config() can be called as part of the
1.1460 +** implementation of an application-defined [sqlite3_os_init()].
1.1461 +**
1.1462 +** The first argument to sqlite3_config() is an integer
1.1463 +** [configuration option] that determines
1.1464 +** what property of SQLite is to be configured. Subsequent arguments
1.1465 +** vary depending on the [configuration option]
1.1466 +** in the first argument.
1.1467 +**
1.1468 +** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1.1469 +** ^If the option is unknown or SQLite is unable to set the option
1.1470 +** then this routine returns a non-zero [error code].
1.1471 +*/
1.1472 +SQLITE_API int sqlite3_config(int, ...);
1.1473 +
1.1474 +/*
1.1475 +** CAPI3REF: Configure database connections
1.1476 +**
1.1477 +** The sqlite3_db_config() interface is used to make configuration
1.1478 +** changes to a [database connection]. The interface is similar to
1.1479 +** [sqlite3_config()] except that the changes apply to a single
1.1480 +** [database connection] (specified in the first argument).
1.1481 +**
1.1482 +** The second argument to sqlite3_db_config(D,V,...) is the
1.1483 +** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1.1484 +** that indicates what aspect of the [database connection] is being configured.
1.1485 +** Subsequent arguments vary depending on the configuration verb.
1.1486 +**
1.1487 +** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1.1488 +** the call is considered successful.
1.1489 +*/
1.1490 +SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1.1491 +
1.1492 +/*
1.1493 +** CAPI3REF: Memory Allocation Routines
1.1494 +**
1.1495 +** An instance of this object defines the interface between SQLite
1.1496 +** and low-level memory allocation routines.
1.1497 +**
1.1498 +** This object is used in only one place in the SQLite interface.
1.1499 +** A pointer to an instance of this object is the argument to
1.1500 +** [sqlite3_config()] when the configuration option is
1.1501 +** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1.1502 +** By creating an instance of this object
1.1503 +** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1.1504 +** during configuration, an application can specify an alternative
1.1505 +** memory allocation subsystem for SQLite to use for all of its
1.1506 +** dynamic memory needs.
1.1507 +**
1.1508 +** Note that SQLite comes with several [built-in memory allocators]
1.1509 +** that are perfectly adequate for the overwhelming majority of applications
1.1510 +** and that this object is only useful to a tiny minority of applications
1.1511 +** with specialized memory allocation requirements. This object is
1.1512 +** also used during testing of SQLite in order to specify an alternative
1.1513 +** memory allocator that simulates memory out-of-memory conditions in
1.1514 +** order to verify that SQLite recovers gracefully from such
1.1515 +** conditions.
1.1516 +**
1.1517 +** The xMalloc, xRealloc, and xFree methods must work like the
1.1518 +** malloc(), realloc() and free() functions from the standard C library.
1.1519 +** ^SQLite guarantees that the second argument to
1.1520 +** xRealloc is always a value returned by a prior call to xRoundup.
1.1521 +**
1.1522 +** xSize should return the allocated size of a memory allocation
1.1523 +** previously obtained from xMalloc or xRealloc. The allocated size
1.1524 +** is always at least as big as the requested size but may be larger.
1.1525 +**
1.1526 +** The xRoundup method returns what would be the allocated size of
1.1527 +** a memory allocation given a particular requested size. Most memory
1.1528 +** allocators round up memory allocations at least to the next multiple
1.1529 +** of 8. Some allocators round up to a larger multiple or to a power of 2.
1.1530 +** Every memory allocation request coming in through [sqlite3_malloc()]
1.1531 +** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1.1532 +** that causes the corresponding memory allocation to fail.
1.1533 +**
1.1534 +** The xInit method initializes the memory allocator. For example,
1.1535 +** it might allocate any require mutexes or initialize internal data
1.1536 +** structures. The xShutdown method is invoked (indirectly) by
1.1537 +** [sqlite3_shutdown()] and should deallocate any resources acquired
1.1538 +** by xInit. The pAppData pointer is used as the only parameter to
1.1539 +** xInit and xShutdown.
1.1540 +**
1.1541 +** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1.1542 +** the xInit method, so the xInit method need not be threadsafe. The
1.1543 +** xShutdown method is only called from [sqlite3_shutdown()] so it does
1.1544 +** not need to be threadsafe either. For all other methods, SQLite
1.1545 +** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1.1546 +** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1.1547 +** it is by default) and so the methods are automatically serialized.
1.1548 +** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1.1549 +** methods must be threadsafe or else make their own arrangements for
1.1550 +** serialization.
1.1551 +**
1.1552 +** SQLite will never invoke xInit() more than once without an intervening
1.1553 +** call to xShutdown().
1.1554 +*/
1.1555 +typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1.1556 +struct sqlite3_mem_methods {
1.1557 + void *(*xMalloc)(int); /* Memory allocation function */
1.1558 + void (*xFree)(void*); /* Free a prior allocation */
1.1559 + void *(*xRealloc)(void*,int); /* Resize an allocation */
1.1560 + int (*xSize)(void*); /* Return the size of an allocation */
1.1561 + int (*xRoundup)(int); /* Round up request size to allocation size */
1.1562 + int (*xInit)(void*); /* Initialize the memory allocator */
1.1563 + void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1.1564 + void *pAppData; /* Argument to xInit() and xShutdown() */
1.1565 +};
1.1566 +
1.1567 +/*
1.1568 +** CAPI3REF: Configuration Options
1.1569 +** KEYWORDS: {configuration option}
1.1570 +**
1.1571 +** These constants are the available integer configuration options that
1.1572 +** can be passed as the first argument to the [sqlite3_config()] interface.
1.1573 +**
1.1574 +** New configuration options may be added in future releases of SQLite.
1.1575 +** Existing configuration options might be discontinued. Applications
1.1576 +** should check the return code from [sqlite3_config()] to make sure that
1.1577 +** the call worked. The [sqlite3_config()] interface will return a
1.1578 +** non-zero [error code] if a discontinued or unsupported configuration option
1.1579 +** is invoked.
1.1580 +**
1.1581 +** <dl>
1.1582 +** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1.1583 +** <dd>There are no arguments to this option. ^This option sets the
1.1584 +** [threading mode] to Single-thread. In other words, it disables
1.1585 +** all mutexing and puts SQLite into a mode where it can only be used
1.1586 +** by a single thread. ^If SQLite is compiled with
1.1587 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1588 +** it is not possible to change the [threading mode] from its default
1.1589 +** value of Single-thread and so [sqlite3_config()] will return
1.1590 +** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1.1591 +** configuration option.</dd>
1.1592 +**
1.1593 +** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1.1594 +** <dd>There are no arguments to this option. ^This option sets the
1.1595 +** [threading mode] to Multi-thread. In other words, it disables
1.1596 +** mutexing on [database connection] and [prepared statement] objects.
1.1597 +** The application is responsible for serializing access to
1.1598 +** [database connections] and [prepared statements]. But other mutexes
1.1599 +** are enabled so that SQLite will be safe to use in a multi-threaded
1.1600 +** environment as long as no two threads attempt to use the same
1.1601 +** [database connection] at the same time. ^If SQLite is compiled with
1.1602 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1603 +** it is not possible to set the Multi-thread [threading mode] and
1.1604 +** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1.1605 +** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1.1606 +**
1.1607 +** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1.1608 +** <dd>There are no arguments to this option. ^This option sets the
1.1609 +** [threading mode] to Serialized. In other words, this option enables
1.1610 +** all mutexes including the recursive
1.1611 +** mutexes on [database connection] and [prepared statement] objects.
1.1612 +** In this mode (which is the default when SQLite is compiled with
1.1613 +** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1.1614 +** to [database connections] and [prepared statements] so that the
1.1615 +** application is free to use the same [database connection] or the
1.1616 +** same [prepared statement] in different threads at the same time.
1.1617 +** ^If SQLite is compiled with
1.1618 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1619 +** it is not possible to set the Serialized [threading mode] and
1.1620 +** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1.1621 +** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1.1622 +**
1.1623 +** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1.1624 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1625 +** instance of the [sqlite3_mem_methods] structure. The argument specifies
1.1626 +** alternative low-level memory allocation routines to be used in place of
1.1627 +** the memory allocation routines built into SQLite.)^ ^SQLite makes
1.1628 +** its own private copy of the content of the [sqlite3_mem_methods] structure
1.1629 +** before the [sqlite3_config()] call returns.</dd>
1.1630 +**
1.1631 +** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1.1632 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1633 +** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
1.1634 +** structure is filled with the currently defined memory allocation routines.)^
1.1635 +** This option can be used to overload the default memory allocation
1.1636 +** routines with a wrapper that simulations memory allocation failure or
1.1637 +** tracks memory usage, for example. </dd>
1.1638 +**
1.1639 +** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1.1640 +** <dd> ^This option takes single argument of type int, interpreted as a
1.1641 +** boolean, which enables or disables the collection of memory allocation
1.1642 +** statistics. ^(When memory allocation statistics are disabled, the
1.1643 +** following SQLite interfaces become non-operational:
1.1644 +** <ul>
1.1645 +** <li> [sqlite3_memory_used()]
1.1646 +** <li> [sqlite3_memory_highwater()]
1.1647 +** <li> [sqlite3_soft_heap_limit64()]
1.1648 +** <li> [sqlite3_status()]
1.1649 +** </ul>)^
1.1650 +** ^Memory allocation statistics are enabled by default unless SQLite is
1.1651 +** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1.1652 +** allocation statistics are disabled by default.
1.1653 +** </dd>
1.1654 +**
1.1655 +** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1.1656 +** <dd> ^This option specifies a static memory buffer that SQLite can use for
1.1657 +** scratch memory. There are three arguments: A pointer an 8-byte
1.1658 +** aligned memory buffer from which the scratch allocations will be
1.1659 +** drawn, the size of each scratch allocation (sz),
1.1660 +** and the maximum number of scratch allocations (N). The sz
1.1661 +** argument must be a multiple of 16.
1.1662 +** The first argument must be a pointer to an 8-byte aligned buffer
1.1663 +** of at least sz*N bytes of memory.
1.1664 +** ^SQLite will use no more than two scratch buffers per thread. So
1.1665 +** N should be set to twice the expected maximum number of threads.
1.1666 +** ^SQLite will never require a scratch buffer that is more than 6
1.1667 +** times the database page size. ^If SQLite needs needs additional
1.1668 +** scratch memory beyond what is provided by this configuration option, then
1.1669 +** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
1.1670 +**
1.1671 +** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1.1672 +** <dd> ^This option specifies a static memory buffer that SQLite can use for
1.1673 +** the database page cache with the default page cache implementation.
1.1674 +** This configuration should not be used if an application-define page
1.1675 +** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option.
1.1676 +** There are three arguments to this option: A pointer to 8-byte aligned
1.1677 +** memory, the size of each page buffer (sz), and the number of pages (N).
1.1678 +** The sz argument should be the size of the largest database page
1.1679 +** (a power of two between 512 and 32768) plus a little extra for each
1.1680 +** page header. ^The page header size is 20 to 40 bytes depending on
1.1681 +** the host architecture. ^It is harmless, apart from the wasted memory,
1.1682 +** to make sz a little too large. The first
1.1683 +** argument should point to an allocation of at least sz*N bytes of memory.
1.1684 +** ^SQLite will use the memory provided by the first argument to satisfy its
1.1685 +** memory needs for the first N pages that it adds to cache. ^If additional
1.1686 +** page cache memory is needed beyond what is provided by this option, then
1.1687 +** SQLite goes to [sqlite3_malloc()] for the additional storage space.
1.1688 +** The pointer in the first argument must
1.1689 +** be aligned to an 8-byte boundary or subsequent behavior of SQLite
1.1690 +** will be undefined.</dd>
1.1691 +**
1.1692 +** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1.1693 +** <dd> ^This option specifies a static memory buffer that SQLite will use
1.1694 +** for all of its dynamic memory allocation needs beyond those provided
1.1695 +** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
1.1696 +** There are three arguments: An 8-byte aligned pointer to the memory,
1.1697 +** the number of bytes in the memory buffer, and the minimum allocation size.
1.1698 +** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1.1699 +** to using its default memory allocator (the system malloc() implementation),
1.1700 +** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
1.1701 +** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
1.1702 +** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
1.1703 +** allocator is engaged to handle all of SQLites memory allocation needs.
1.1704 +** The first pointer (the memory pointer) must be aligned to an 8-byte
1.1705 +** boundary or subsequent behavior of SQLite will be undefined.
1.1706 +** The minimum allocation size is capped at 2**12. Reasonable values
1.1707 +** for the minimum allocation size are 2**5 through 2**8.</dd>
1.1708 +**
1.1709 +** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1.1710 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1711 +** instance of the [sqlite3_mutex_methods] structure. The argument specifies
1.1712 +** alternative low-level mutex routines to be used in place
1.1713 +** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
1.1714 +** content of the [sqlite3_mutex_methods] structure before the call to
1.1715 +** [sqlite3_config()] returns. ^If SQLite is compiled with
1.1716 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1717 +** the entire mutexing subsystem is omitted from the build and hence calls to
1.1718 +** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1.1719 +** return [SQLITE_ERROR].</dd>
1.1720 +**
1.1721 +** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1.1722 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1723 +** instance of the [sqlite3_mutex_methods] structure. The
1.1724 +** [sqlite3_mutex_methods]
1.1725 +** structure is filled with the currently defined mutex routines.)^
1.1726 +** This option can be used to overload the default mutex allocation
1.1727 +** routines with a wrapper used to track mutex usage for performance
1.1728 +** profiling or testing, for example. ^If SQLite is compiled with
1.1729 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1730 +** the entire mutexing subsystem is omitted from the build and hence calls to
1.1731 +** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1.1732 +** return [SQLITE_ERROR].</dd>
1.1733 +**
1.1734 +** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1.1735 +** <dd> ^(This option takes two arguments that determine the default
1.1736 +** memory allocation for the lookaside memory allocator on each
1.1737 +** [database connection]. The first argument is the
1.1738 +** size of each lookaside buffer slot and the second is the number of
1.1739 +** slots allocated to each database connection.)^ ^(This option sets the
1.1740 +** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1.1741 +** verb to [sqlite3_db_config()] can be used to change the lookaside
1.1742 +** configuration on individual connections.)^ </dd>
1.1743 +**
1.1744 +** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1.1745 +** <dd> ^(This option takes a single argument which is a pointer to
1.1746 +** an [sqlite3_pcache_methods2] object. This object specifies the interface
1.1747 +** to a custom page cache implementation.)^ ^SQLite makes a copy of the
1.1748 +** object and uses it for page cache memory allocations.</dd>
1.1749 +**
1.1750 +** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1.1751 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1752 +** [sqlite3_pcache_methods2] object. SQLite copies of the current
1.1753 +** page cache implementation into that object.)^ </dd>
1.1754 +**
1.1755 +** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1.1756 +** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1.1757 +** global [error log].
1.1758 +** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1.1759 +** function with a call signature of void(*)(void*,int,const char*),
1.1760 +** and a pointer to void. ^If the function pointer is not NULL, it is
1.1761 +** invoked by [sqlite3_log()] to process each logging event. ^If the
1.1762 +** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1.1763 +** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1.1764 +** passed through as the first parameter to the application-defined logger
1.1765 +** function whenever that function is invoked. ^The second parameter to
1.1766 +** the logger function is a copy of the first parameter to the corresponding
1.1767 +** [sqlite3_log()] call and is intended to be a [result code] or an
1.1768 +** [extended result code]. ^The third parameter passed to the logger is
1.1769 +** log message after formatting via [sqlite3_snprintf()].
1.1770 +** The SQLite logging interface is not reentrant; the logger function
1.1771 +** supplied by the application must not invoke any SQLite interface.
1.1772 +** In a multi-threaded application, the application-defined logger
1.1773 +** function must be threadsafe. </dd>
1.1774 +**
1.1775 +** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1.1776 +** <dd>^(This option takes a single argument of type int. If non-zero, then
1.1777 +** URI handling is globally enabled. If the parameter is zero, then URI handling
1.1778 +** is globally disabled.)^ ^If URI handling is globally enabled, all filenames
1.1779 +** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
1.1780 +** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1.1781 +** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1.1782 +** connection is opened. ^If it is globally disabled, filenames are
1.1783 +** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1.1784 +** database connection is opened. ^(By default, URI handling is globally
1.1785 +** disabled. The default value may be changed by compiling with the
1.1786 +** [SQLITE_USE_URI] symbol defined.)^
1.1787 +**
1.1788 +** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1.1789 +** <dd>^This option takes a single integer argument which is interpreted as
1.1790 +** a boolean in order to enable or disable the use of covering indices for
1.1791 +** full table scans in the query optimizer. ^The default setting is determined
1.1792 +** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1.1793 +** if that compile-time option is omitted.
1.1794 +** The ability to disable the use of covering indices for full table scans
1.1795 +** is because some incorrectly coded legacy applications might malfunction
1.1796 +** when the optimization is enabled. Providing the ability to
1.1797 +** disable the optimization allows the older, buggy application code to work
1.1798 +** without change even with newer versions of SQLite.
1.1799 +**
1.1800 +** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1.1801 +** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1.1802 +** <dd> These options are obsolete and should not be used by new code.
1.1803 +** They are retained for backwards compatibility but are now no-ops.
1.1804 +** </dd>
1.1805 +**
1.1806 +** [[SQLITE_CONFIG_SQLLOG]]
1.1807 +** <dt>SQLITE_CONFIG_SQLLOG
1.1808 +** <dd>This option is only available if sqlite is compiled with the
1.1809 +** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1.1810 +** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1.1811 +** The second should be of type (void*). The callback is invoked by the library
1.1812 +** in three separate circumstances, identified by the value passed as the
1.1813 +** fourth parameter. If the fourth parameter is 0, then the database connection
1.1814 +** passed as the second argument has just been opened. The third argument
1.1815 +** points to a buffer containing the name of the main database file. If the
1.1816 +** fourth parameter is 1, then the SQL statement that the third parameter
1.1817 +** points to has just been executed. Or, if the fourth parameter is 2, then
1.1818 +** the connection being passed as the second parameter is being closed. The
1.1819 +** third parameter is passed NULL In this case. An example of using this
1.1820 +** configuration option can be seen in the "test_sqllog.c" source file in
1.1821 +** the canonical SQLite source tree.</dd>
1.1822 +**
1.1823 +** [[SQLITE_CONFIG_MMAP_SIZE]]
1.1824 +** <dt>SQLITE_CONFIG_MMAP_SIZE
1.1825 +** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
1.1826 +** that are the default mmap size limit (the default setting for
1.1827 +** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
1.1828 +** ^The default setting can be overridden by each database connection using
1.1829 +** either the [PRAGMA mmap_size] command, or by using the
1.1830 +** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
1.1831 +** cannot be changed at run-time. Nor may the maximum allowed mmap size
1.1832 +** exceed the compile-time maximum mmap size set by the
1.1833 +** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
1.1834 +** ^If either argument to this option is negative, then that argument is
1.1835 +** changed to its compile-time default.
1.1836 +**
1.1837 +** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
1.1838 +** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
1.1839 +** <dd>^This option is only available if SQLite is compiled for Windows
1.1840 +** with the [SQLITE_WIN32_MALLOC] pre-processor macro defined.
1.1841 +** SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
1.1842 +** that specifies the maximum size of the created heap.
1.1843 +** </dl>
1.1844 +*/
1.1845 +#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
1.1846 +#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
1.1847 +#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
1.1848 +#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
1.1849 +#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
1.1850 +#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
1.1851 +#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
1.1852 +#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
1.1853 +#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
1.1854 +#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
1.1855 +#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
1.1856 +/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
1.1857 +#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
1.1858 +#define SQLITE_CONFIG_PCACHE 14 /* no-op */
1.1859 +#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
1.1860 +#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
1.1861 +#define SQLITE_CONFIG_URI 17 /* int */
1.1862 +#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
1.1863 +#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
1.1864 +#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
1.1865 +#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
1.1866 +#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
1.1867 +#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
1.1868 +
1.1869 +/*
1.1870 +** CAPI3REF: Database Connection Configuration Options
1.1871 +**
1.1872 +** These constants are the available integer configuration options that
1.1873 +** can be passed as the second argument to the [sqlite3_db_config()] interface.
1.1874 +**
1.1875 +** New configuration options may be added in future releases of SQLite.
1.1876 +** Existing configuration options might be discontinued. Applications
1.1877 +** should check the return code from [sqlite3_db_config()] to make sure that
1.1878 +** the call worked. ^The [sqlite3_db_config()] interface will return a
1.1879 +** non-zero [error code] if a discontinued or unsupported configuration option
1.1880 +** is invoked.
1.1881 +**
1.1882 +** <dl>
1.1883 +** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1.1884 +** <dd> ^This option takes three additional arguments that determine the
1.1885 +** [lookaside memory allocator] configuration for the [database connection].
1.1886 +** ^The first argument (the third parameter to [sqlite3_db_config()] is a
1.1887 +** pointer to a memory buffer to use for lookaside memory.
1.1888 +** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1.1889 +** may be NULL in which case SQLite will allocate the
1.1890 +** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1.1891 +** size of each lookaside buffer slot. ^The third argument is the number of
1.1892 +** slots. The size of the buffer in the first argument must be greater than
1.1893 +** or equal to the product of the second and third arguments. The buffer
1.1894 +** must be aligned to an 8-byte boundary. ^If the second argument to
1.1895 +** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1.1896 +** rounded down to the next smaller multiple of 8. ^(The lookaside memory
1.1897 +** configuration for a database connection can only be changed when that
1.1898 +** connection is not currently using lookaside memory, or in other words
1.1899 +** when the "current value" returned by
1.1900 +** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
1.1901 +** Any attempt to change the lookaside memory configuration when lookaside
1.1902 +** memory is in use leaves the configuration unchanged and returns
1.1903 +** [SQLITE_BUSY].)^</dd>
1.1904 +**
1.1905 +** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
1.1906 +** <dd> ^This option is used to enable or disable the enforcement of
1.1907 +** [foreign key constraints]. There should be two additional arguments.
1.1908 +** The first argument is an integer which is 0 to disable FK enforcement,
1.1909 +** positive to enable FK enforcement or negative to leave FK enforcement
1.1910 +** unchanged. The second parameter is a pointer to an integer into which
1.1911 +** is written 0 or 1 to indicate whether FK enforcement is off or on
1.1912 +** following this call. The second parameter may be a NULL pointer, in
1.1913 +** which case the FK enforcement setting is not reported back. </dd>
1.1914 +**
1.1915 +** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
1.1916 +** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
1.1917 +** There should be two additional arguments.
1.1918 +** The first argument is an integer which is 0 to disable triggers,
1.1919 +** positive to enable triggers or negative to leave the setting unchanged.
1.1920 +** The second parameter is a pointer to an integer into which
1.1921 +** is written 0 or 1 to indicate whether triggers are disabled or enabled
1.1922 +** following this call. The second parameter may be a NULL pointer, in
1.1923 +** which case the trigger setting is not reported back. </dd>
1.1924 +**
1.1925 +** </dl>
1.1926 +*/
1.1927 +#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
1.1928 +#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
1.1929 +#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
1.1930 +
1.1931 +
1.1932 +/*
1.1933 +** CAPI3REF: Enable Or Disable Extended Result Codes
1.1934 +**
1.1935 +** ^The sqlite3_extended_result_codes() routine enables or disables the
1.1936 +** [extended result codes] feature of SQLite. ^The extended result
1.1937 +** codes are disabled by default for historical compatibility.
1.1938 +*/
1.1939 +SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
1.1940 +
1.1941 +/*
1.1942 +** CAPI3REF: Last Insert Rowid
1.1943 +**
1.1944 +** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
1.1945 +** has a unique 64-bit signed
1.1946 +** integer key called the [ROWID | "rowid"]. ^The rowid is always available
1.1947 +** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
1.1948 +** names are not also used by explicitly declared columns. ^If
1.1949 +** the table has a column of type [INTEGER PRIMARY KEY] then that column
1.1950 +** is another alias for the rowid.
1.1951 +**
1.1952 +** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the
1.1953 +** most recent successful [INSERT] into a rowid table or [virtual table]
1.1954 +** on database connection D.
1.1955 +** ^Inserts into [WITHOUT ROWID] tables are not recorded.
1.1956 +** ^If no successful [INSERT]s into rowid tables
1.1957 +** have ever occurred on the database connection D,
1.1958 +** then sqlite3_last_insert_rowid(D) returns zero.
1.1959 +**
1.1960 +** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
1.1961 +** method, then this routine will return the [rowid] of the inserted
1.1962 +** row as long as the trigger or virtual table method is running.
1.1963 +** But once the trigger or virtual table method ends, the value returned
1.1964 +** by this routine reverts to what it was before the trigger or virtual
1.1965 +** table method began.)^
1.1966 +**
1.1967 +** ^An [INSERT] that fails due to a constraint violation is not a
1.1968 +** successful [INSERT] and does not change the value returned by this
1.1969 +** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
1.1970 +** and INSERT OR ABORT make no changes to the return value of this
1.1971 +** routine when their insertion fails. ^(When INSERT OR REPLACE
1.1972 +** encounters a constraint violation, it does not fail. The
1.1973 +** INSERT continues to completion after deleting rows that caused
1.1974 +** the constraint problem so INSERT OR REPLACE will always change
1.1975 +** the return value of this interface.)^
1.1976 +**
1.1977 +** ^For the purposes of this routine, an [INSERT] is considered to
1.1978 +** be successful even if it is subsequently rolled back.
1.1979 +**
1.1980 +** This function is accessible to SQL statements via the
1.1981 +** [last_insert_rowid() SQL function].
1.1982 +**
1.1983 +** If a separate thread performs a new [INSERT] on the same
1.1984 +** database connection while the [sqlite3_last_insert_rowid()]
1.1985 +** function is running and thus changes the last insert [rowid],
1.1986 +** then the value returned by [sqlite3_last_insert_rowid()] is
1.1987 +** unpredictable and might not equal either the old or the new
1.1988 +** last insert [rowid].
1.1989 +*/
1.1990 +SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
1.1991 +
1.1992 +/*
1.1993 +** CAPI3REF: Count The Number Of Rows Modified
1.1994 +**
1.1995 +** ^This function returns the number of database rows that were changed
1.1996 +** or inserted or deleted by the most recently completed SQL statement
1.1997 +** on the [database connection] specified by the first parameter.
1.1998 +** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
1.1999 +** or [DELETE] statement are counted. Auxiliary changes caused by
1.2000 +** triggers or [foreign key actions] are not counted.)^ Use the
1.2001 +** [sqlite3_total_changes()] function to find the total number of changes
1.2002 +** including changes caused by triggers and foreign key actions.
1.2003 +**
1.2004 +** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
1.2005 +** are not counted. Only real table changes are counted.
1.2006 +**
1.2007 +** ^(A "row change" is a change to a single row of a single table
1.2008 +** caused by an INSERT, DELETE, or UPDATE statement. Rows that
1.2009 +** are changed as side effects of [REPLACE] constraint resolution,
1.2010 +** rollback, ABORT processing, [DROP TABLE], or by any other
1.2011 +** mechanisms do not count as direct row changes.)^
1.2012 +**
1.2013 +** A "trigger context" is a scope of execution that begins and
1.2014 +** ends with the script of a [CREATE TRIGGER | trigger].
1.2015 +** Most SQL statements are
1.2016 +** evaluated outside of any trigger. This is the "top level"
1.2017 +** trigger context. If a trigger fires from the top level, a
1.2018 +** new trigger context is entered for the duration of that one
1.2019 +** trigger. Subtriggers create subcontexts for their duration.
1.2020 +**
1.2021 +** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
1.2022 +** not create a new trigger context.
1.2023 +**
1.2024 +** ^This function returns the number of direct row changes in the
1.2025 +** most recent INSERT, UPDATE, or DELETE statement within the same
1.2026 +** trigger context.
1.2027 +**
1.2028 +** ^Thus, when called from the top level, this function returns the
1.2029 +** number of changes in the most recent INSERT, UPDATE, or DELETE
1.2030 +** that also occurred at the top level. ^(Within the body of a trigger,
1.2031 +** the sqlite3_changes() interface can be called to find the number of
1.2032 +** changes in the most recently completed INSERT, UPDATE, or DELETE
1.2033 +** statement within the body of the same trigger.
1.2034 +** However, the number returned does not include changes
1.2035 +** caused by subtriggers since those have their own context.)^
1.2036 +**
1.2037 +** See also the [sqlite3_total_changes()] interface, the
1.2038 +** [count_changes pragma], and the [changes() SQL function].
1.2039 +**
1.2040 +** If a separate thread makes changes on the same database connection
1.2041 +** while [sqlite3_changes()] is running then the value returned
1.2042 +** is unpredictable and not meaningful.
1.2043 +*/
1.2044 +SQLITE_API int sqlite3_changes(sqlite3*);
1.2045 +
1.2046 +/*
1.2047 +** CAPI3REF: Total Number Of Rows Modified
1.2048 +**
1.2049 +** ^This function returns the number of row changes caused by [INSERT],
1.2050 +** [UPDATE] or [DELETE] statements since the [database connection] was opened.
1.2051 +** ^(The count returned by sqlite3_total_changes() includes all changes
1.2052 +** from all [CREATE TRIGGER | trigger] contexts and changes made by
1.2053 +** [foreign key actions]. However,
1.2054 +** the count does not include changes used to implement [REPLACE] constraints,
1.2055 +** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
1.2056 +** count does not include rows of views that fire an [INSTEAD OF trigger],
1.2057 +** though if the INSTEAD OF trigger makes changes of its own, those changes
1.2058 +** are counted.)^
1.2059 +** ^The sqlite3_total_changes() function counts the changes as soon as
1.2060 +** the statement that makes them is completed (when the statement handle
1.2061 +** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
1.2062 +**
1.2063 +** See also the [sqlite3_changes()] interface, the
1.2064 +** [count_changes pragma], and the [total_changes() SQL function].
1.2065 +**
1.2066 +** If a separate thread makes changes on the same database connection
1.2067 +** while [sqlite3_total_changes()] is running then the value
1.2068 +** returned is unpredictable and not meaningful.
1.2069 +*/
1.2070 +SQLITE_API int sqlite3_total_changes(sqlite3*);
1.2071 +
1.2072 +/*
1.2073 +** CAPI3REF: Interrupt A Long-Running Query
1.2074 +**
1.2075 +** ^This function causes any pending database operation to abort and
1.2076 +** return at its earliest opportunity. This routine is typically
1.2077 +** called in response to a user action such as pressing "Cancel"
1.2078 +** or Ctrl-C where the user wants a long query operation to halt
1.2079 +** immediately.
1.2080 +**
1.2081 +** ^It is safe to call this routine from a thread different from the
1.2082 +** thread that is currently running the database operation. But it
1.2083 +** is not safe to call this routine with a [database connection] that
1.2084 +** is closed or might close before sqlite3_interrupt() returns.
1.2085 +**
1.2086 +** ^If an SQL operation is very nearly finished at the time when
1.2087 +** sqlite3_interrupt() is called, then it might not have an opportunity
1.2088 +** to be interrupted and might continue to completion.
1.2089 +**
1.2090 +** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
1.2091 +** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
1.2092 +** that is inside an explicit transaction, then the entire transaction
1.2093 +** will be rolled back automatically.
1.2094 +**
1.2095 +** ^The sqlite3_interrupt(D) call is in effect until all currently running
1.2096 +** SQL statements on [database connection] D complete. ^Any new SQL statements
1.2097 +** that are started after the sqlite3_interrupt() call and before the
1.2098 +** running statements reaches zero are interrupted as if they had been
1.2099 +** running prior to the sqlite3_interrupt() call. ^New SQL statements
1.2100 +** that are started after the running statement count reaches zero are
1.2101 +** not effected by the sqlite3_interrupt().
1.2102 +** ^A call to sqlite3_interrupt(D) that occurs when there are no running
1.2103 +** SQL statements is a no-op and has no effect on SQL statements
1.2104 +** that are started after the sqlite3_interrupt() call returns.
1.2105 +**
1.2106 +** If the database connection closes while [sqlite3_interrupt()]
1.2107 +** is running then bad things will likely happen.
1.2108 +*/
1.2109 +SQLITE_API void sqlite3_interrupt(sqlite3*);
1.2110 +
1.2111 +/*
1.2112 +** CAPI3REF: Determine If An SQL Statement Is Complete
1.2113 +**
1.2114 +** These routines are useful during command-line input to determine if the
1.2115 +** currently entered text seems to form a complete SQL statement or
1.2116 +** if additional input is needed before sending the text into
1.2117 +** SQLite for parsing. ^These routines return 1 if the input string
1.2118 +** appears to be a complete SQL statement. ^A statement is judged to be
1.2119 +** complete if it ends with a semicolon token and is not a prefix of a
1.2120 +** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
1.2121 +** string literals or quoted identifier names or comments are not
1.2122 +** independent tokens (they are part of the token in which they are
1.2123 +** embedded) and thus do not count as a statement terminator. ^Whitespace
1.2124 +** and comments that follow the final semicolon are ignored.
1.2125 +**
1.2126 +** ^These routines return 0 if the statement is incomplete. ^If a
1.2127 +** memory allocation fails, then SQLITE_NOMEM is returned.
1.2128 +**
1.2129 +** ^These routines do not parse the SQL statements thus
1.2130 +** will not detect syntactically incorrect SQL.
1.2131 +**
1.2132 +** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
1.2133 +** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
1.2134 +** automatically by sqlite3_complete16(). If that initialization fails,
1.2135 +** then the return value from sqlite3_complete16() will be non-zero
1.2136 +** regardless of whether or not the input SQL is complete.)^
1.2137 +**
1.2138 +** The input to [sqlite3_complete()] must be a zero-terminated
1.2139 +** UTF-8 string.
1.2140 +**
1.2141 +** The input to [sqlite3_complete16()] must be a zero-terminated
1.2142 +** UTF-16 string in native byte order.
1.2143 +*/
1.2144 +SQLITE_API int sqlite3_complete(const char *sql);
1.2145 +SQLITE_API int sqlite3_complete16(const void *sql);
1.2146 +
1.2147 +/*
1.2148 +** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
1.2149 +**
1.2150 +** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
1.2151 +** that might be invoked with argument P whenever
1.2152 +** an attempt is made to access a database table associated with
1.2153 +** [database connection] D when another thread
1.2154 +** or process has the table locked.
1.2155 +** The sqlite3_busy_handler() interface is used to implement
1.2156 +** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
1.2157 +**
1.2158 +** ^If the busy callback is NULL, then [SQLITE_BUSY]
1.2159 +** is returned immediately upon encountering the lock. ^If the busy callback
1.2160 +** is not NULL, then the callback might be invoked with two arguments.
1.2161 +**
1.2162 +** ^The first argument to the busy handler is a copy of the void* pointer which
1.2163 +** is the third argument to sqlite3_busy_handler(). ^The second argument to
1.2164 +** the busy handler callback is the number of times that the busy handler has
1.2165 +** been invoked for the same locking event. ^If the
1.2166 +** busy callback returns 0, then no additional attempts are made to
1.2167 +** access the database and [SQLITE_BUSY] is returned
1.2168 +** to the application.
1.2169 +** ^If the callback returns non-zero, then another attempt
1.2170 +** is made to access the database and the cycle repeats.
1.2171 +**
1.2172 +** The presence of a busy handler does not guarantee that it will be invoked
1.2173 +** when there is lock contention. ^If SQLite determines that invoking the busy
1.2174 +** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1.2175 +** to the application instead of invoking the
1.2176 +** busy handler.
1.2177 +** Consider a scenario where one process is holding a read lock that
1.2178 +** it is trying to promote to a reserved lock and
1.2179 +** a second process is holding a reserved lock that it is trying
1.2180 +** to promote to an exclusive lock. The first process cannot proceed
1.2181 +** because it is blocked by the second and the second process cannot
1.2182 +** proceed because it is blocked by the first. If both processes
1.2183 +** invoke the busy handlers, neither will make any progress. Therefore,
1.2184 +** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
1.2185 +** will induce the first process to release its read lock and allow
1.2186 +** the second process to proceed.
1.2187 +**
1.2188 +** ^The default busy callback is NULL.
1.2189 +**
1.2190 +** ^(There can only be a single busy handler defined for each
1.2191 +** [database connection]. Setting a new busy handler clears any
1.2192 +** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
1.2193 +** or evaluating [PRAGMA busy_timeout=N] will change the
1.2194 +** busy handler and thus clear any previously set busy handler.
1.2195 +**
1.2196 +** The busy callback should not take any actions which modify the
1.2197 +** database connection that invoked the busy handler. In other words,
1.2198 +** the busy handler is not reentrant. Any such actions
1.2199 +** result in undefined behavior.
1.2200 +**
1.2201 +** A busy handler must not close the database connection
1.2202 +** or [prepared statement] that invoked the busy handler.
1.2203 +*/
1.2204 +SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
1.2205 +
1.2206 +/*
1.2207 +** CAPI3REF: Set A Busy Timeout
1.2208 +**
1.2209 +** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
1.2210 +** for a specified amount of time when a table is locked. ^The handler
1.2211 +** will sleep multiple times until at least "ms" milliseconds of sleeping
1.2212 +** have accumulated. ^After at least "ms" milliseconds of sleeping,
1.2213 +** the handler returns 0 which causes [sqlite3_step()] to return
1.2214 +** [SQLITE_BUSY].
1.2215 +**
1.2216 +** ^Calling this routine with an argument less than or equal to zero
1.2217 +** turns off all busy handlers.
1.2218 +**
1.2219 +** ^(There can only be a single busy handler for a particular
1.2220 +** [database connection] any any given moment. If another busy handler
1.2221 +** was defined (using [sqlite3_busy_handler()]) prior to calling
1.2222 +** this routine, that other busy handler is cleared.)^
1.2223 +**
1.2224 +** See also: [PRAGMA busy_timeout]
1.2225 +*/
1.2226 +SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
1.2227 +
1.2228 +/*
1.2229 +** CAPI3REF: Convenience Routines For Running Queries
1.2230 +**
1.2231 +** This is a legacy interface that is preserved for backwards compatibility.
1.2232 +** Use of this interface is not recommended.
1.2233 +**
1.2234 +** Definition: A <b>result table</b> is memory data structure created by the
1.2235 +** [sqlite3_get_table()] interface. A result table records the
1.2236 +** complete query results from one or more queries.
1.2237 +**
1.2238 +** The table conceptually has a number of rows and columns. But
1.2239 +** these numbers are not part of the result table itself. These
1.2240 +** numbers are obtained separately. Let N be the number of rows
1.2241 +** and M be the number of columns.
1.2242 +**
1.2243 +** A result table is an array of pointers to zero-terminated UTF-8 strings.
1.2244 +** There are (N+1)*M elements in the array. The first M pointers point
1.2245 +** to zero-terminated strings that contain the names of the columns.
1.2246 +** The remaining entries all point to query results. NULL values result
1.2247 +** in NULL pointers. All other values are in their UTF-8 zero-terminated
1.2248 +** string representation as returned by [sqlite3_column_text()].
1.2249 +**
1.2250 +** A result table might consist of one or more memory allocations.
1.2251 +** It is not safe to pass a result table directly to [sqlite3_free()].
1.2252 +** A result table should be deallocated using [sqlite3_free_table()].
1.2253 +**
1.2254 +** ^(As an example of the result table format, suppose a query result
1.2255 +** is as follows:
1.2256 +**
1.2257 +** <blockquote><pre>
1.2258 +** Name | Age
1.2259 +** -----------------------
1.2260 +** Alice | 43
1.2261 +** Bob | 28
1.2262 +** Cindy | 21
1.2263 +** </pre></blockquote>
1.2264 +**
1.2265 +** There are two column (M==2) and three rows (N==3). Thus the
1.2266 +** result table has 8 entries. Suppose the result table is stored
1.2267 +** in an array names azResult. Then azResult holds this content:
1.2268 +**
1.2269 +** <blockquote><pre>
1.2270 +** azResult[0] = "Name";
1.2271 +** azResult[1] = "Age";
1.2272 +** azResult[2] = "Alice";
1.2273 +** azResult[3] = "43";
1.2274 +** azResult[4] = "Bob";
1.2275 +** azResult[5] = "28";
1.2276 +** azResult[6] = "Cindy";
1.2277 +** azResult[7] = "21";
1.2278 +** </pre></blockquote>)^
1.2279 +**
1.2280 +** ^The sqlite3_get_table() function evaluates one or more
1.2281 +** semicolon-separated SQL statements in the zero-terminated UTF-8
1.2282 +** string of its 2nd parameter and returns a result table to the
1.2283 +** pointer given in its 3rd parameter.
1.2284 +**
1.2285 +** After the application has finished with the result from sqlite3_get_table(),
1.2286 +** it must pass the result table pointer to sqlite3_free_table() in order to
1.2287 +** release the memory that was malloced. Because of the way the
1.2288 +** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
1.2289 +** function must not try to call [sqlite3_free()] directly. Only
1.2290 +** [sqlite3_free_table()] is able to release the memory properly and safely.
1.2291 +**
1.2292 +** The sqlite3_get_table() interface is implemented as a wrapper around
1.2293 +** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
1.2294 +** to any internal data structures of SQLite. It uses only the public
1.2295 +** interface defined here. As a consequence, errors that occur in the
1.2296 +** wrapper layer outside of the internal [sqlite3_exec()] call are not
1.2297 +** reflected in subsequent calls to [sqlite3_errcode()] or
1.2298 +** [sqlite3_errmsg()].
1.2299 +*/
1.2300 +SQLITE_API int sqlite3_get_table(
1.2301 + sqlite3 *db, /* An open database */
1.2302 + const char *zSql, /* SQL to be evaluated */
1.2303 + char ***pazResult, /* Results of the query */
1.2304 + int *pnRow, /* Number of result rows written here */
1.2305 + int *pnColumn, /* Number of result columns written here */
1.2306 + char **pzErrmsg /* Error msg written here */
1.2307 +);
1.2308 +SQLITE_API void sqlite3_free_table(char **result);
1.2309 +
1.2310 +/*
1.2311 +** CAPI3REF: Formatted String Printing Functions
1.2312 +**
1.2313 +** These routines are work-alikes of the "printf()" family of functions
1.2314 +** from the standard C library.
1.2315 +**
1.2316 +** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
1.2317 +** results into memory obtained from [sqlite3_malloc()].
1.2318 +** The strings returned by these two routines should be
1.2319 +** released by [sqlite3_free()]. ^Both routines return a
1.2320 +** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
1.2321 +** memory to hold the resulting string.
1.2322 +**
1.2323 +** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
1.2324 +** the standard C library. The result is written into the
1.2325 +** buffer supplied as the second parameter whose size is given by
1.2326 +** the first parameter. Note that the order of the
1.2327 +** first two parameters is reversed from snprintf().)^ This is an
1.2328 +** historical accident that cannot be fixed without breaking
1.2329 +** backwards compatibility. ^(Note also that sqlite3_snprintf()
1.2330 +** returns a pointer to its buffer instead of the number of
1.2331 +** characters actually written into the buffer.)^ We admit that
1.2332 +** the number of characters written would be a more useful return
1.2333 +** value but we cannot change the implementation of sqlite3_snprintf()
1.2334 +** now without breaking compatibility.
1.2335 +**
1.2336 +** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
1.2337 +** guarantees that the buffer is always zero-terminated. ^The first
1.2338 +** parameter "n" is the total size of the buffer, including space for
1.2339 +** the zero terminator. So the longest string that can be completely
1.2340 +** written will be n-1 characters.
1.2341 +**
1.2342 +** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
1.2343 +**
1.2344 +** These routines all implement some additional formatting
1.2345 +** options that are useful for constructing SQL statements.
1.2346 +** All of the usual printf() formatting options apply. In addition, there
1.2347 +** is are "%q", "%Q", and "%z" options.
1.2348 +**
1.2349 +** ^(The %q option works like %s in that it substitutes a nul-terminated
1.2350 +** string from the argument list. But %q also doubles every '\'' character.
1.2351 +** %q is designed for use inside a string literal.)^ By doubling each '\''
1.2352 +** character it escapes that character and allows it to be inserted into
1.2353 +** the string.
1.2354 +**
1.2355 +** For example, assume the string variable zText contains text as follows:
1.2356 +**
1.2357 +** <blockquote><pre>
1.2358 +** char *zText = "It's a happy day!";
1.2359 +** </pre></blockquote>
1.2360 +**
1.2361 +** One can use this text in an SQL statement as follows:
1.2362 +**
1.2363 +** <blockquote><pre>
1.2364 +** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
1.2365 +** sqlite3_exec(db, zSQL, 0, 0, 0);
1.2366 +** sqlite3_free(zSQL);
1.2367 +** </pre></blockquote>
1.2368 +**
1.2369 +** Because the %q format string is used, the '\'' character in zText
1.2370 +** is escaped and the SQL generated is as follows:
1.2371 +**
1.2372 +** <blockquote><pre>
1.2373 +** INSERT INTO table1 VALUES('It''s a happy day!')
1.2374 +** </pre></blockquote>
1.2375 +**
1.2376 +** This is correct. Had we used %s instead of %q, the generated SQL
1.2377 +** would have looked like this:
1.2378 +**
1.2379 +** <blockquote><pre>
1.2380 +** INSERT INTO table1 VALUES('It's a happy day!');
1.2381 +** </pre></blockquote>
1.2382 +**
1.2383 +** This second example is an SQL syntax error. As a general rule you should
1.2384 +** always use %q instead of %s when inserting text into a string literal.
1.2385 +**
1.2386 +** ^(The %Q option works like %q except it also adds single quotes around
1.2387 +** the outside of the total string. Additionally, if the parameter in the
1.2388 +** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
1.2389 +** single quotes).)^ So, for example, one could say:
1.2390 +**
1.2391 +** <blockquote><pre>
1.2392 +** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
1.2393 +** sqlite3_exec(db, zSQL, 0, 0, 0);
1.2394 +** sqlite3_free(zSQL);
1.2395 +** </pre></blockquote>
1.2396 +**
1.2397 +** The code above will render a correct SQL statement in the zSQL
1.2398 +** variable even if the zText variable is a NULL pointer.
1.2399 +**
1.2400 +** ^(The "%z" formatting option works like "%s" but with the
1.2401 +** addition that after the string has been read and copied into
1.2402 +** the result, [sqlite3_free()] is called on the input string.)^
1.2403 +*/
1.2404 +SQLITE_API char *sqlite3_mprintf(const char*,...);
1.2405 +SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
1.2406 +SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
1.2407 +SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
1.2408 +
1.2409 +/*
1.2410 +** CAPI3REF: Memory Allocation Subsystem
1.2411 +**
1.2412 +** The SQLite core uses these three routines for all of its own
1.2413 +** internal memory allocation needs. "Core" in the previous sentence
1.2414 +** does not include operating-system specific VFS implementation. The
1.2415 +** Windows VFS uses native malloc() and free() for some operations.
1.2416 +**
1.2417 +** ^The sqlite3_malloc() routine returns a pointer to a block
1.2418 +** of memory at least N bytes in length, where N is the parameter.
1.2419 +** ^If sqlite3_malloc() is unable to obtain sufficient free
1.2420 +** memory, it returns a NULL pointer. ^If the parameter N to
1.2421 +** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
1.2422 +** a NULL pointer.
1.2423 +**
1.2424 +** ^Calling sqlite3_free() with a pointer previously returned
1.2425 +** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
1.2426 +** that it might be reused. ^The sqlite3_free() routine is
1.2427 +** a no-op if is called with a NULL pointer. Passing a NULL pointer
1.2428 +** to sqlite3_free() is harmless. After being freed, memory
1.2429 +** should neither be read nor written. Even reading previously freed
1.2430 +** memory might result in a segmentation fault or other severe error.
1.2431 +** Memory corruption, a segmentation fault, or other severe error
1.2432 +** might result if sqlite3_free() is called with a non-NULL pointer that
1.2433 +** was not obtained from sqlite3_malloc() or sqlite3_realloc().
1.2434 +**
1.2435 +** ^(The sqlite3_realloc() interface attempts to resize a
1.2436 +** prior memory allocation to be at least N bytes, where N is the
1.2437 +** second parameter. The memory allocation to be resized is the first
1.2438 +** parameter.)^ ^ If the first parameter to sqlite3_realloc()
1.2439 +** is a NULL pointer then its behavior is identical to calling
1.2440 +** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
1.2441 +** ^If the second parameter to sqlite3_realloc() is zero or
1.2442 +** negative then the behavior is exactly the same as calling
1.2443 +** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
1.2444 +** ^sqlite3_realloc() returns a pointer to a memory allocation
1.2445 +** of at least N bytes in size or NULL if sufficient memory is unavailable.
1.2446 +** ^If M is the size of the prior allocation, then min(N,M) bytes
1.2447 +** of the prior allocation are copied into the beginning of buffer returned
1.2448 +** by sqlite3_realloc() and the prior allocation is freed.
1.2449 +** ^If sqlite3_realloc() returns NULL, then the prior allocation
1.2450 +** is not freed.
1.2451 +**
1.2452 +** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
1.2453 +** is always aligned to at least an 8 byte boundary, or to a
1.2454 +** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
1.2455 +** option is used.
1.2456 +**
1.2457 +** In SQLite version 3.5.0 and 3.5.1, it was possible to define
1.2458 +** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
1.2459 +** implementation of these routines to be omitted. That capability
1.2460 +** is no longer provided. Only built-in memory allocators can be used.
1.2461 +**
1.2462 +** Prior to SQLite version 3.7.10, the Windows OS interface layer called
1.2463 +** the system malloc() and free() directly when converting
1.2464 +** filenames between the UTF-8 encoding used by SQLite
1.2465 +** and whatever filename encoding is used by the particular Windows
1.2466 +** installation. Memory allocation errors were detected, but
1.2467 +** they were reported back as [SQLITE_CANTOPEN] or
1.2468 +** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
1.2469 +**
1.2470 +** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
1.2471 +** must be either NULL or else pointers obtained from a prior
1.2472 +** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
1.2473 +** not yet been released.
1.2474 +**
1.2475 +** The application must not read or write any part of
1.2476 +** a block of memory after it has been released using
1.2477 +** [sqlite3_free()] or [sqlite3_realloc()].
1.2478 +*/
1.2479 +SQLITE_API void *sqlite3_malloc(int);
1.2480 +SQLITE_API void *sqlite3_realloc(void*, int);
1.2481 +SQLITE_API void sqlite3_free(void*);
1.2482 +
1.2483 +/*
1.2484 +** CAPI3REF: Memory Allocator Statistics
1.2485 +**
1.2486 +** SQLite provides these two interfaces for reporting on the status
1.2487 +** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
1.2488 +** routines, which form the built-in memory allocation subsystem.
1.2489 +**
1.2490 +** ^The [sqlite3_memory_used()] routine returns the number of bytes
1.2491 +** of memory currently outstanding (malloced but not freed).
1.2492 +** ^The [sqlite3_memory_highwater()] routine returns the maximum
1.2493 +** value of [sqlite3_memory_used()] since the high-water mark
1.2494 +** was last reset. ^The values returned by [sqlite3_memory_used()] and
1.2495 +** [sqlite3_memory_highwater()] include any overhead
1.2496 +** added by SQLite in its implementation of [sqlite3_malloc()],
1.2497 +** but not overhead added by the any underlying system library
1.2498 +** routines that [sqlite3_malloc()] may call.
1.2499 +**
1.2500 +** ^The memory high-water mark is reset to the current value of
1.2501 +** [sqlite3_memory_used()] if and only if the parameter to
1.2502 +** [sqlite3_memory_highwater()] is true. ^The value returned
1.2503 +** by [sqlite3_memory_highwater(1)] is the high-water mark
1.2504 +** prior to the reset.
1.2505 +*/
1.2506 +SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
1.2507 +SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
1.2508 +
1.2509 +/*
1.2510 +** CAPI3REF: Pseudo-Random Number Generator
1.2511 +**
1.2512 +** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
1.2513 +** select random [ROWID | ROWIDs] when inserting new records into a table that
1.2514 +** already uses the largest possible [ROWID]. The PRNG is also used for
1.2515 +** the build-in random() and randomblob() SQL functions. This interface allows
1.2516 +** applications to access the same PRNG for other purposes.
1.2517 +**
1.2518 +** ^A call to this routine stores N bytes of randomness into buffer P.
1.2519 +** ^If N is less than one, then P can be a NULL pointer.
1.2520 +**
1.2521 +** ^If this routine has not been previously called or if the previous
1.2522 +** call had N less than one, then the PRNG is seeded using randomness
1.2523 +** obtained from the xRandomness method of the default [sqlite3_vfs] object.
1.2524 +** ^If the previous call to this routine had an N of 1 or more then
1.2525 +** the pseudo-randomness is generated
1.2526 +** internally and without recourse to the [sqlite3_vfs] xRandomness
1.2527 +** method.
1.2528 +*/
1.2529 +SQLITE_API void sqlite3_randomness(int N, void *P);
1.2530 +
1.2531 +/*
1.2532 +** CAPI3REF: Compile-Time Authorization Callbacks
1.2533 +**
1.2534 +** ^This routine registers an authorizer callback with a particular
1.2535 +** [database connection], supplied in the first argument.
1.2536 +** ^The authorizer callback is invoked as SQL statements are being compiled
1.2537 +** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
1.2538 +** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
1.2539 +** points during the compilation process, as logic is being created
1.2540 +** to perform various actions, the authorizer callback is invoked to
1.2541 +** see if those actions are allowed. ^The authorizer callback should
1.2542 +** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
1.2543 +** specific action but allow the SQL statement to continue to be
1.2544 +** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
1.2545 +** rejected with an error. ^If the authorizer callback returns
1.2546 +** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
1.2547 +** then the [sqlite3_prepare_v2()] or equivalent call that triggered
1.2548 +** the authorizer will fail with an error message.
1.2549 +**
1.2550 +** When the callback returns [SQLITE_OK], that means the operation
1.2551 +** requested is ok. ^When the callback returns [SQLITE_DENY], the
1.2552 +** [sqlite3_prepare_v2()] or equivalent call that triggered the
1.2553 +** authorizer will fail with an error message explaining that
1.2554 +** access is denied.
1.2555 +**
1.2556 +** ^The first parameter to the authorizer callback is a copy of the third
1.2557 +** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
1.2558 +** to the callback is an integer [SQLITE_COPY | action code] that specifies
1.2559 +** the particular action to be authorized. ^The third through sixth parameters
1.2560 +** to the callback are zero-terminated strings that contain additional
1.2561 +** details about the action to be authorized.
1.2562 +**
1.2563 +** ^If the action code is [SQLITE_READ]
1.2564 +** and the callback returns [SQLITE_IGNORE] then the
1.2565 +** [prepared statement] statement is constructed to substitute
1.2566 +** a NULL value in place of the table column that would have
1.2567 +** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
1.2568 +** return can be used to deny an untrusted user access to individual
1.2569 +** columns of a table.
1.2570 +** ^If the action code is [SQLITE_DELETE] and the callback returns
1.2571 +** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
1.2572 +** [truncate optimization] is disabled and all rows are deleted individually.
1.2573 +**
1.2574 +** An authorizer is used when [sqlite3_prepare | preparing]
1.2575 +** SQL statements from an untrusted source, to ensure that the SQL statements
1.2576 +** do not try to access data they are not allowed to see, or that they do not
1.2577 +** try to execute malicious statements that damage the database. For
1.2578 +** example, an application may allow a user to enter arbitrary
1.2579 +** SQL queries for evaluation by a database. But the application does
1.2580 +** not want the user to be able to make arbitrary changes to the
1.2581 +** database. An authorizer could then be put in place while the
1.2582 +** user-entered SQL is being [sqlite3_prepare | prepared] that
1.2583 +** disallows everything except [SELECT] statements.
1.2584 +**
1.2585 +** Applications that need to process SQL from untrusted sources
1.2586 +** might also consider lowering resource limits using [sqlite3_limit()]
1.2587 +** and limiting database size using the [max_page_count] [PRAGMA]
1.2588 +** in addition to using an authorizer.
1.2589 +**
1.2590 +** ^(Only a single authorizer can be in place on a database connection
1.2591 +** at a time. Each call to sqlite3_set_authorizer overrides the
1.2592 +** previous call.)^ ^Disable the authorizer by installing a NULL callback.
1.2593 +** The authorizer is disabled by default.
1.2594 +**
1.2595 +** The authorizer callback must not do anything that will modify
1.2596 +** the database connection that invoked the authorizer callback.
1.2597 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
1.2598 +** database connections for the meaning of "modify" in this paragraph.
1.2599 +**
1.2600 +** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
1.2601 +** statement might be re-prepared during [sqlite3_step()] due to a
1.2602 +** schema change. Hence, the application should ensure that the
1.2603 +** correct authorizer callback remains in place during the [sqlite3_step()].
1.2604 +**
1.2605 +** ^Note that the authorizer callback is invoked only during
1.2606 +** [sqlite3_prepare()] or its variants. Authorization is not
1.2607 +** performed during statement evaluation in [sqlite3_step()], unless
1.2608 +** as stated in the previous paragraph, sqlite3_step() invokes
1.2609 +** sqlite3_prepare_v2() to reprepare a statement after a schema change.
1.2610 +*/
1.2611 +SQLITE_API int sqlite3_set_authorizer(
1.2612 + sqlite3*,
1.2613 + int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
1.2614 + void *pUserData
1.2615 +);
1.2616 +
1.2617 +/*
1.2618 +** CAPI3REF: Authorizer Return Codes
1.2619 +**
1.2620 +** The [sqlite3_set_authorizer | authorizer callback function] must
1.2621 +** return either [SQLITE_OK] or one of these two constants in order
1.2622 +** to signal SQLite whether or not the action is permitted. See the
1.2623 +** [sqlite3_set_authorizer | authorizer documentation] for additional
1.2624 +** information.
1.2625 +**
1.2626 +** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
1.2627 +** returned from the [sqlite3_vtab_on_conflict()] interface.
1.2628 +*/
1.2629 +#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
1.2630 +#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
1.2631 +
1.2632 +/*
1.2633 +** CAPI3REF: Authorizer Action Codes
1.2634 +**
1.2635 +** The [sqlite3_set_authorizer()] interface registers a callback function
1.2636 +** that is invoked to authorize certain SQL statement actions. The
1.2637 +** second parameter to the callback is an integer code that specifies
1.2638 +** what action is being authorized. These are the integer action codes that
1.2639 +** the authorizer callback may be passed.
1.2640 +**
1.2641 +** These action code values signify what kind of operation is to be
1.2642 +** authorized. The 3rd and 4th parameters to the authorization
1.2643 +** callback function will be parameters or NULL depending on which of these
1.2644 +** codes is used as the second parameter. ^(The 5th parameter to the
1.2645 +** authorizer callback is the name of the database ("main", "temp",
1.2646 +** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
1.2647 +** is the name of the inner-most trigger or view that is responsible for
1.2648 +** the access attempt or NULL if this access attempt is directly from
1.2649 +** top-level SQL code.
1.2650 +*/
1.2651 +/******************************************* 3rd ************ 4th ***********/
1.2652 +#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
1.2653 +#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
1.2654 +#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
1.2655 +#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
1.2656 +#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
1.2657 +#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
1.2658 +#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
1.2659 +#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
1.2660 +#define SQLITE_DELETE 9 /* Table Name NULL */
1.2661 +#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
1.2662 +#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
1.2663 +#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
1.2664 +#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
1.2665 +#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
1.2666 +#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
1.2667 +#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
1.2668 +#define SQLITE_DROP_VIEW 17 /* View Name NULL */
1.2669 +#define SQLITE_INSERT 18 /* Table Name NULL */
1.2670 +#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
1.2671 +#define SQLITE_READ 20 /* Table Name Column Name */
1.2672 +#define SQLITE_SELECT 21 /* NULL NULL */
1.2673 +#define SQLITE_TRANSACTION 22 /* Operation NULL */
1.2674 +#define SQLITE_UPDATE 23 /* Table Name Column Name */
1.2675 +#define SQLITE_ATTACH 24 /* Filename NULL */
1.2676 +#define SQLITE_DETACH 25 /* Database Name NULL */
1.2677 +#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
1.2678 +#define SQLITE_REINDEX 27 /* Index Name NULL */
1.2679 +#define SQLITE_ANALYZE 28 /* Table Name NULL */
1.2680 +#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
1.2681 +#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
1.2682 +#define SQLITE_FUNCTION 31 /* NULL Function Name */
1.2683 +#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
1.2684 +#define SQLITE_COPY 0 /* No longer used */
1.2685 +#define SQLITE_RECURSIVE 33 /* NULL NULL */
1.2686 +
1.2687 +/*
1.2688 +** CAPI3REF: Tracing And Profiling Functions
1.2689 +**
1.2690 +** These routines register callback functions that can be used for
1.2691 +** tracing and profiling the execution of SQL statements.
1.2692 +**
1.2693 +** ^The callback function registered by sqlite3_trace() is invoked at
1.2694 +** various times when an SQL statement is being run by [sqlite3_step()].
1.2695 +** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
1.2696 +** SQL statement text as the statement first begins executing.
1.2697 +** ^(Additional sqlite3_trace() callbacks might occur
1.2698 +** as each triggered subprogram is entered. The callbacks for triggers
1.2699 +** contain a UTF-8 SQL comment that identifies the trigger.)^
1.2700 +**
1.2701 +** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
1.2702 +** the length of [bound parameter] expansion in the output of sqlite3_trace().
1.2703 +**
1.2704 +** ^The callback function registered by sqlite3_profile() is invoked
1.2705 +** as each SQL statement finishes. ^The profile callback contains
1.2706 +** the original statement text and an estimate of wall-clock time
1.2707 +** of how long that statement took to run. ^The profile callback
1.2708 +** time is in units of nanoseconds, however the current implementation
1.2709 +** is only capable of millisecond resolution so the six least significant
1.2710 +** digits in the time are meaningless. Future versions of SQLite
1.2711 +** might provide greater resolution on the profiler callback. The
1.2712 +** sqlite3_profile() function is considered experimental and is
1.2713 +** subject to change in future versions of SQLite.
1.2714 +*/
1.2715 +SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
1.2716 +SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
1.2717 + void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
1.2718 +
1.2719 +/*
1.2720 +** CAPI3REF: Query Progress Callbacks
1.2721 +**
1.2722 +** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
1.2723 +** function X to be invoked periodically during long running calls to
1.2724 +** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
1.2725 +** database connection D. An example use for this
1.2726 +** interface is to keep a GUI updated during a large query.
1.2727 +**
1.2728 +** ^The parameter P is passed through as the only parameter to the
1.2729 +** callback function X. ^The parameter N is the approximate number of
1.2730 +** [virtual machine instructions] that are evaluated between successive
1.2731 +** invocations of the callback X. ^If N is less than one then the progress
1.2732 +** handler is disabled.
1.2733 +**
1.2734 +** ^Only a single progress handler may be defined at one time per
1.2735 +** [database connection]; setting a new progress handler cancels the
1.2736 +** old one. ^Setting parameter X to NULL disables the progress handler.
1.2737 +** ^The progress handler is also disabled by setting N to a value less
1.2738 +** than 1.
1.2739 +**
1.2740 +** ^If the progress callback returns non-zero, the operation is
1.2741 +** interrupted. This feature can be used to implement a
1.2742 +** "Cancel" button on a GUI progress dialog box.
1.2743 +**
1.2744 +** The progress handler callback must not do anything that will modify
1.2745 +** the database connection that invoked the progress handler.
1.2746 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
1.2747 +** database connections for the meaning of "modify" in this paragraph.
1.2748 +**
1.2749 +*/
1.2750 +SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
1.2751 +
1.2752 +/*
1.2753 +** CAPI3REF: Opening A New Database Connection
1.2754 +**
1.2755 +** ^These routines open an SQLite database file as specified by the
1.2756 +** filename argument. ^The filename argument is interpreted as UTF-8 for
1.2757 +** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
1.2758 +** order for sqlite3_open16(). ^(A [database connection] handle is usually
1.2759 +** returned in *ppDb, even if an error occurs. The only exception is that
1.2760 +** if SQLite is unable to allocate memory to hold the [sqlite3] object,
1.2761 +** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
1.2762 +** object.)^ ^(If the database is opened (and/or created) successfully, then
1.2763 +** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
1.2764 +** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
1.2765 +** an English language description of the error following a failure of any
1.2766 +** of the sqlite3_open() routines.
1.2767 +**
1.2768 +** ^The default encoding for the database will be UTF-8 if
1.2769 +** sqlite3_open() or sqlite3_open_v2() is called and
1.2770 +** UTF-16 in the native byte order if sqlite3_open16() is used.
1.2771 +**
1.2772 +** Whether or not an error occurs when it is opened, resources
1.2773 +** associated with the [database connection] handle should be released by
1.2774 +** passing it to [sqlite3_close()] when it is no longer required.
1.2775 +**
1.2776 +** The sqlite3_open_v2() interface works like sqlite3_open()
1.2777 +** except that it accepts two additional parameters for additional control
1.2778 +** over the new database connection. ^(The flags parameter to
1.2779 +** sqlite3_open_v2() can take one of
1.2780 +** the following three values, optionally combined with the
1.2781 +** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
1.2782 +** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
1.2783 +**
1.2784 +** <dl>
1.2785 +** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
1.2786 +** <dd>The database is opened in read-only mode. If the database does not
1.2787 +** already exist, an error is returned.</dd>)^
1.2788 +**
1.2789 +** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
1.2790 +** <dd>The database is opened for reading and writing if possible, or reading
1.2791 +** only if the file is write protected by the operating system. In either
1.2792 +** case the database must already exist, otherwise an error is returned.</dd>)^
1.2793 +**
1.2794 +** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
1.2795 +** <dd>The database is opened for reading and writing, and is created if
1.2796 +** it does not already exist. This is the behavior that is always used for
1.2797 +** sqlite3_open() and sqlite3_open16().</dd>)^
1.2798 +** </dl>
1.2799 +**
1.2800 +** If the 3rd parameter to sqlite3_open_v2() is not one of the
1.2801 +** combinations shown above optionally combined with other
1.2802 +** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
1.2803 +** then the behavior is undefined.
1.2804 +**
1.2805 +** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
1.2806 +** opens in the multi-thread [threading mode] as long as the single-thread
1.2807 +** mode has not been set at compile-time or start-time. ^If the
1.2808 +** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
1.2809 +** in the serialized [threading mode] unless single-thread was
1.2810 +** previously selected at compile-time or start-time.
1.2811 +** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
1.2812 +** eligible to use [shared cache mode], regardless of whether or not shared
1.2813 +** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
1.2814 +** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
1.2815 +** participate in [shared cache mode] even if it is enabled.
1.2816 +**
1.2817 +** ^The fourth parameter to sqlite3_open_v2() is the name of the
1.2818 +** [sqlite3_vfs] object that defines the operating system interface that
1.2819 +** the new database connection should use. ^If the fourth parameter is
1.2820 +** a NULL pointer then the default [sqlite3_vfs] object is used.
1.2821 +**
1.2822 +** ^If the filename is ":memory:", then a private, temporary in-memory database
1.2823 +** is created for the connection. ^This in-memory database will vanish when
1.2824 +** the database connection is closed. Future versions of SQLite might
1.2825 +** make use of additional special filenames that begin with the ":" character.
1.2826 +** It is recommended that when a database filename actually does begin with
1.2827 +** a ":" character you should prefix the filename with a pathname such as
1.2828 +** "./" to avoid ambiguity.
1.2829 +**
1.2830 +** ^If the filename is an empty string, then a private, temporary
1.2831 +** on-disk database will be created. ^This private database will be
1.2832 +** automatically deleted as soon as the database connection is closed.
1.2833 +**
1.2834 +** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
1.2835 +**
1.2836 +** ^If [URI filename] interpretation is enabled, and the filename argument
1.2837 +** begins with "file:", then the filename is interpreted as a URI. ^URI
1.2838 +** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
1.2839 +** set in the fourth argument to sqlite3_open_v2(), or if it has
1.2840 +** been enabled globally using the [SQLITE_CONFIG_URI] option with the
1.2841 +** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
1.2842 +** As of SQLite version 3.7.7, URI filename interpretation is turned off
1.2843 +** by default, but future releases of SQLite might enable URI filename
1.2844 +** interpretation by default. See "[URI filenames]" for additional
1.2845 +** information.
1.2846 +**
1.2847 +** URI filenames are parsed according to RFC 3986. ^If the URI contains an
1.2848 +** authority, then it must be either an empty string or the string
1.2849 +** "localhost". ^If the authority is not an empty string or "localhost", an
1.2850 +** error is returned to the caller. ^The fragment component of a URI, if
1.2851 +** present, is ignored.
1.2852 +**
1.2853 +** ^SQLite uses the path component of the URI as the name of the disk file
1.2854 +** which contains the database. ^If the path begins with a '/' character,
1.2855 +** then it is interpreted as an absolute path. ^If the path does not begin
1.2856 +** with a '/' (meaning that the authority section is omitted from the URI)
1.2857 +** then the path is interpreted as a relative path.
1.2858 +** ^On windows, the first component of an absolute path
1.2859 +** is a drive specification (e.g. "C:").
1.2860 +**
1.2861 +** [[core URI query parameters]]
1.2862 +** The query component of a URI may contain parameters that are interpreted
1.2863 +** either by SQLite itself, or by a [VFS | custom VFS implementation].
1.2864 +** SQLite interprets the following three query parameters:
1.2865 +**
1.2866 +** <ul>
1.2867 +** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
1.2868 +** a VFS object that provides the operating system interface that should
1.2869 +** be used to access the database file on disk. ^If this option is set to
1.2870 +** an empty string the default VFS object is used. ^Specifying an unknown
1.2871 +** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
1.2872 +** present, then the VFS specified by the option takes precedence over
1.2873 +** the value passed as the fourth parameter to sqlite3_open_v2().
1.2874 +**
1.2875 +** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
1.2876 +** "rwc", or "memory". Attempting to set it to any other value is
1.2877 +** an error)^.
1.2878 +** ^If "ro" is specified, then the database is opened for read-only
1.2879 +** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
1.2880 +** third argument to sqlite3_open_v2(). ^If the mode option is set to
1.2881 +** "rw", then the database is opened for read-write (but not create)
1.2882 +** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
1.2883 +** been set. ^Value "rwc" is equivalent to setting both
1.2884 +** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
1.2885 +** set to "memory" then a pure [in-memory database] that never reads
1.2886 +** or writes from disk is used. ^It is an error to specify a value for
1.2887 +** the mode parameter that is less restrictive than that specified by
1.2888 +** the flags passed in the third parameter to sqlite3_open_v2().
1.2889 +**
1.2890 +** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
1.2891 +** "private". ^Setting it to "shared" is equivalent to setting the
1.2892 +** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
1.2893 +** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
1.2894 +** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
1.2895 +** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
1.2896 +** a URI filename, its value overrides any behavior requested by setting
1.2897 +** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
1.2898 +**
1.2899 +** <li> <b>psow</b>: ^The psow parameter may be "true" (or "on" or "yes" or
1.2900 +** "1") or "false" (or "off" or "no" or "0") to indicate that the
1.2901 +** [powersafe overwrite] property does or does not apply to the
1.2902 +** storage media on which the database file resides. ^The psow query
1.2903 +** parameter only works for the built-in unix and Windows VFSes.
1.2904 +**
1.2905 +** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
1.2906 +** which if set disables file locking in rollback journal modes. This
1.2907 +** is useful for accessing a database on a filesystem that does not
1.2908 +** support locking. Caution: Database corruption might result if two
1.2909 +** or more processes write to the same database and any one of those
1.2910 +** processes uses nolock=1.
1.2911 +**
1.2912 +** <li> <b>immutable</b>: ^The immutable parameter is a boolean query
1.2913 +** parameter that indicates that the database file is stored on
1.2914 +** read-only media. ^When immutable is set, SQLite assumes that the
1.2915 +** database file cannot be changed, even by a process with higher
1.2916 +** privilege, and so the database is opened read-only and all locking
1.2917 +** and change detection is disabled. Caution: Setting the immutable
1.2918 +** property on a database file that does in fact change can result
1.2919 +** in incorrect query results and/or [SQLITE_CORRUPT] errors.
1.2920 +** See also: [SQLITE_IOCAP_IMMUTABLE].
1.2921 +**
1.2922 +** </ul>
1.2923 +**
1.2924 +** ^Specifying an unknown parameter in the query component of a URI is not an
1.2925 +** error. Future versions of SQLite might understand additional query
1.2926 +** parameters. See "[query parameters with special meaning to SQLite]" for
1.2927 +** additional information.
1.2928 +**
1.2929 +** [[URI filename examples]] <h3>URI filename examples</h3>
1.2930 +**
1.2931 +** <table border="1" align=center cellpadding=5>
1.2932 +** <tr><th> URI filenames <th> Results
1.2933 +** <tr><td> file:data.db <td>
1.2934 +** Open the file "data.db" in the current directory.
1.2935 +** <tr><td> file:/home/fred/data.db<br>
1.2936 +** file:///home/fred/data.db <br>
1.2937 +** file://localhost/home/fred/data.db <br> <td>
1.2938 +** Open the database file "/home/fred/data.db".
1.2939 +** <tr><td> file://darkstar/home/fred/data.db <td>
1.2940 +** An error. "darkstar" is not a recognized authority.
1.2941 +** <tr><td style="white-space:nowrap">
1.2942 +** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
1.2943 +** <td> Windows only: Open the file "data.db" on fred's desktop on drive
1.2944 +** C:. Note that the %20 escaping in this example is not strictly
1.2945 +** necessary - space characters can be used literally
1.2946 +** in URI filenames.
1.2947 +** <tr><td> file:data.db?mode=ro&cache=private <td>
1.2948 +** Open file "data.db" in the current directory for read-only access.
1.2949 +** Regardless of whether or not shared-cache mode is enabled by
1.2950 +** default, use a private cache.
1.2951 +** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
1.2952 +** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
1.2953 +** that uses dot-files in place of posix advisory locking.
1.2954 +** <tr><td> file:data.db?mode=readonly <td>
1.2955 +** An error. "readonly" is not a valid option for the "mode" parameter.
1.2956 +** </table>
1.2957 +**
1.2958 +** ^URI hexadecimal escape sequences (%HH) are supported within the path and
1.2959 +** query components of a URI. A hexadecimal escape sequence consists of a
1.2960 +** percent sign - "%" - followed by exactly two hexadecimal digits
1.2961 +** specifying an octet value. ^Before the path or query components of a
1.2962 +** URI filename are interpreted, they are encoded using UTF-8 and all
1.2963 +** hexadecimal escape sequences replaced by a single byte containing the
1.2964 +** corresponding octet. If this process generates an invalid UTF-8 encoding,
1.2965 +** the results are undefined.
1.2966 +**
1.2967 +** <b>Note to Windows users:</b> The encoding used for the filename argument
1.2968 +** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
1.2969 +** codepage is currently defined. Filenames containing international
1.2970 +** characters must be converted to UTF-8 prior to passing them into
1.2971 +** sqlite3_open() or sqlite3_open_v2().
1.2972 +**
1.2973 +** <b>Note to Windows Runtime users:</b> The temporary directory must be set
1.2974 +** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
1.2975 +** features that require the use of temporary files may fail.
1.2976 +**
1.2977 +** See also: [sqlite3_temp_directory]
1.2978 +*/
1.2979 +SQLITE_API int sqlite3_open(
1.2980 + const char *filename, /* Database filename (UTF-8) */
1.2981 + sqlite3 **ppDb /* OUT: SQLite db handle */
1.2982 +);
1.2983 +SQLITE_API int sqlite3_open16(
1.2984 + const void *filename, /* Database filename (UTF-16) */
1.2985 + sqlite3 **ppDb /* OUT: SQLite db handle */
1.2986 +);
1.2987 +SQLITE_API int sqlite3_open_v2(
1.2988 + const char *filename, /* Database filename (UTF-8) */
1.2989 + sqlite3 **ppDb, /* OUT: SQLite db handle */
1.2990 + int flags, /* Flags */
1.2991 + const char *zVfs /* Name of VFS module to use */
1.2992 +);
1.2993 +
1.2994 +/*
1.2995 +** CAPI3REF: Obtain Values For URI Parameters
1.2996 +**
1.2997 +** These are utility routines, useful to VFS implementations, that check
1.2998 +** to see if a database file was a URI that contained a specific query
1.2999 +** parameter, and if so obtains the value of that query parameter.
1.3000 +**
1.3001 +** If F is the database filename pointer passed into the xOpen() method of
1.3002 +** a VFS implementation when the flags parameter to xOpen() has one or
1.3003 +** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
1.3004 +** P is the name of the query parameter, then
1.3005 +** sqlite3_uri_parameter(F,P) returns the value of the P
1.3006 +** parameter if it exists or a NULL pointer if P does not appear as a
1.3007 +** query parameter on F. If P is a query parameter of F
1.3008 +** has no explicit value, then sqlite3_uri_parameter(F,P) returns
1.3009 +** a pointer to an empty string.
1.3010 +**
1.3011 +** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
1.3012 +** parameter and returns true (1) or false (0) according to the value
1.3013 +** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
1.3014 +** value of query parameter P is one of "yes", "true", or "on" in any
1.3015 +** case or if the value begins with a non-zero number. The
1.3016 +** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
1.3017 +** query parameter P is one of "no", "false", or "off" in any case or
1.3018 +** if the value begins with a numeric zero. If P is not a query
1.3019 +** parameter on F or if the value of P is does not match any of the
1.3020 +** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
1.3021 +**
1.3022 +** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
1.3023 +** 64-bit signed integer and returns that integer, or D if P does not
1.3024 +** exist. If the value of P is something other than an integer, then
1.3025 +** zero is returned.
1.3026 +**
1.3027 +** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
1.3028 +** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
1.3029 +** is not a database file pathname pointer that SQLite passed into the xOpen
1.3030 +** VFS method, then the behavior of this routine is undefined and probably
1.3031 +** undesirable.
1.3032 +*/
1.3033 +SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
1.3034 +SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
1.3035 +SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
1.3036 +
1.3037 +
1.3038 +/*
1.3039 +** CAPI3REF: Error Codes And Messages
1.3040 +**
1.3041 +** ^The sqlite3_errcode() interface returns the numeric [result code] or
1.3042 +** [extended result code] for the most recent failed sqlite3_* API call
1.3043 +** associated with a [database connection]. If a prior API call failed
1.3044 +** but the most recent API call succeeded, the return value from
1.3045 +** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
1.3046 +** interface is the same except that it always returns the
1.3047 +** [extended result code] even when extended result codes are
1.3048 +** disabled.
1.3049 +**
1.3050 +** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
1.3051 +** text that describes the error, as either UTF-8 or UTF-16 respectively.
1.3052 +** ^(Memory to hold the error message string is managed internally.
1.3053 +** The application does not need to worry about freeing the result.
1.3054 +** However, the error string might be overwritten or deallocated by
1.3055 +** subsequent calls to other SQLite interface functions.)^
1.3056 +**
1.3057 +** ^The sqlite3_errstr() interface returns the English-language text
1.3058 +** that describes the [result code], as UTF-8.
1.3059 +** ^(Memory to hold the error message string is managed internally
1.3060 +** and must not be freed by the application)^.
1.3061 +**
1.3062 +** When the serialized [threading mode] is in use, it might be the
1.3063 +** case that a second error occurs on a separate thread in between
1.3064 +** the time of the first error and the call to these interfaces.
1.3065 +** When that happens, the second error will be reported since these
1.3066 +** interfaces always report the most recent result. To avoid
1.3067 +** this, each thread can obtain exclusive use of the [database connection] D
1.3068 +** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
1.3069 +** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
1.3070 +** all calls to the interfaces listed here are completed.
1.3071 +**
1.3072 +** If an interface fails with SQLITE_MISUSE, that means the interface
1.3073 +** was invoked incorrectly by the application. In that case, the
1.3074 +** error code and message may or may not be set.
1.3075 +*/
1.3076 +SQLITE_API int sqlite3_errcode(sqlite3 *db);
1.3077 +SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
1.3078 +SQLITE_API const char *sqlite3_errmsg(sqlite3*);
1.3079 +SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
1.3080 +SQLITE_API const char *sqlite3_errstr(int);
1.3081 +
1.3082 +/*
1.3083 +** CAPI3REF: SQL Statement Object
1.3084 +** KEYWORDS: {prepared statement} {prepared statements}
1.3085 +**
1.3086 +** An instance of this object represents a single SQL statement.
1.3087 +** This object is variously known as a "prepared statement" or a
1.3088 +** "compiled SQL statement" or simply as a "statement".
1.3089 +**
1.3090 +** The life of a statement object goes something like this:
1.3091 +**
1.3092 +** <ol>
1.3093 +** <li> Create the object using [sqlite3_prepare_v2()] or a related
1.3094 +** function.
1.3095 +** <li> Bind values to [host parameters] using the sqlite3_bind_*()
1.3096 +** interfaces.
1.3097 +** <li> Run the SQL by calling [sqlite3_step()] one or more times.
1.3098 +** <li> Reset the statement using [sqlite3_reset()] then go back
1.3099 +** to step 2. Do this zero or more times.
1.3100 +** <li> Destroy the object using [sqlite3_finalize()].
1.3101 +** </ol>
1.3102 +**
1.3103 +** Refer to documentation on individual methods above for additional
1.3104 +** information.
1.3105 +*/
1.3106 +typedef struct sqlite3_stmt sqlite3_stmt;
1.3107 +
1.3108 +/*
1.3109 +** CAPI3REF: Run-time Limits
1.3110 +**
1.3111 +** ^(This interface allows the size of various constructs to be limited
1.3112 +** on a connection by connection basis. The first parameter is the
1.3113 +** [database connection] whose limit is to be set or queried. The
1.3114 +** second parameter is one of the [limit categories] that define a
1.3115 +** class of constructs to be size limited. The third parameter is the
1.3116 +** new limit for that construct.)^
1.3117 +**
1.3118 +** ^If the new limit is a negative number, the limit is unchanged.
1.3119 +** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
1.3120 +** [limits | hard upper bound]
1.3121 +** set at compile-time by a C preprocessor macro called
1.3122 +** [limits | SQLITE_MAX_<i>NAME</i>].
1.3123 +** (The "_LIMIT_" in the name is changed to "_MAX_".))^
1.3124 +** ^Attempts to increase a limit above its hard upper bound are
1.3125 +** silently truncated to the hard upper bound.
1.3126 +**
1.3127 +** ^Regardless of whether or not the limit was changed, the
1.3128 +** [sqlite3_limit()] interface returns the prior value of the limit.
1.3129 +** ^Hence, to find the current value of a limit without changing it,
1.3130 +** simply invoke this interface with the third parameter set to -1.
1.3131 +**
1.3132 +** Run-time limits are intended for use in applications that manage
1.3133 +** both their own internal database and also databases that are controlled
1.3134 +** by untrusted external sources. An example application might be a
1.3135 +** web browser that has its own databases for storing history and
1.3136 +** separate databases controlled by JavaScript applications downloaded
1.3137 +** off the Internet. The internal databases can be given the
1.3138 +** large, default limits. Databases managed by external sources can
1.3139 +** be given much smaller limits designed to prevent a denial of service
1.3140 +** attack. Developers might also want to use the [sqlite3_set_authorizer()]
1.3141 +** interface to further control untrusted SQL. The size of the database
1.3142 +** created by an untrusted script can be contained using the
1.3143 +** [max_page_count] [PRAGMA].
1.3144 +**
1.3145 +** New run-time limit categories may be added in future releases.
1.3146 +*/
1.3147 +SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
1.3148 +
1.3149 +/*
1.3150 +** CAPI3REF: Run-Time Limit Categories
1.3151 +** KEYWORDS: {limit category} {*limit categories}
1.3152 +**
1.3153 +** These constants define various performance limits
1.3154 +** that can be lowered at run-time using [sqlite3_limit()].
1.3155 +** The synopsis of the meanings of the various limits is shown below.
1.3156 +** Additional information is available at [limits | Limits in SQLite].
1.3157 +**
1.3158 +** <dl>
1.3159 +** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
1.3160 +** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
1.3161 +**
1.3162 +** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
1.3163 +** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
1.3164 +**
1.3165 +** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
1.3166 +** <dd>The maximum number of columns in a table definition or in the
1.3167 +** result set of a [SELECT] or the maximum number of columns in an index
1.3168 +** or in an ORDER BY or GROUP BY clause.</dd>)^
1.3169 +**
1.3170 +** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
1.3171 +** <dd>The maximum depth of the parse tree on any expression.</dd>)^
1.3172 +**
1.3173 +** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
1.3174 +** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
1.3175 +**
1.3176 +** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
1.3177 +** <dd>The maximum number of instructions in a virtual machine program
1.3178 +** used to implement an SQL statement. This limit is not currently
1.3179 +** enforced, though that might be added in some future release of
1.3180 +** SQLite.</dd>)^
1.3181 +**
1.3182 +** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
1.3183 +** <dd>The maximum number of arguments on a function.</dd>)^
1.3184 +**
1.3185 +** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
1.3186 +** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
1.3187 +**
1.3188 +** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
1.3189 +** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
1.3190 +** <dd>The maximum length of the pattern argument to the [LIKE] or
1.3191 +** [GLOB] operators.</dd>)^
1.3192 +**
1.3193 +** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
1.3194 +** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
1.3195 +** <dd>The maximum index number of any [parameter] in an SQL statement.)^
1.3196 +**
1.3197 +** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
1.3198 +** <dd>The maximum depth of recursion for triggers.</dd>)^
1.3199 +** </dl>
1.3200 +*/
1.3201 +#define SQLITE_LIMIT_LENGTH 0
1.3202 +#define SQLITE_LIMIT_SQL_LENGTH 1
1.3203 +#define SQLITE_LIMIT_COLUMN 2
1.3204 +#define SQLITE_LIMIT_EXPR_DEPTH 3
1.3205 +#define SQLITE_LIMIT_COMPOUND_SELECT 4
1.3206 +#define SQLITE_LIMIT_VDBE_OP 5
1.3207 +#define SQLITE_LIMIT_FUNCTION_ARG 6
1.3208 +#define SQLITE_LIMIT_ATTACHED 7
1.3209 +#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
1.3210 +#define SQLITE_LIMIT_VARIABLE_NUMBER 9
1.3211 +#define SQLITE_LIMIT_TRIGGER_DEPTH 10
1.3212 +
1.3213 +/*
1.3214 +** CAPI3REF: Compiling An SQL Statement
1.3215 +** KEYWORDS: {SQL statement compiler}
1.3216 +**
1.3217 +** To execute an SQL query, it must first be compiled into a byte-code
1.3218 +** program using one of these routines.
1.3219 +**
1.3220 +** The first argument, "db", is a [database connection] obtained from a
1.3221 +** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
1.3222 +** [sqlite3_open16()]. The database connection must not have been closed.
1.3223 +**
1.3224 +** The second argument, "zSql", is the statement to be compiled, encoded
1.3225 +** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
1.3226 +** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
1.3227 +** use UTF-16.
1.3228 +**
1.3229 +** ^If the nByte argument is less than zero, then zSql is read up to the
1.3230 +** first zero terminator. ^If nByte is non-negative, then it is the maximum
1.3231 +** number of bytes read from zSql. ^When nByte is non-negative, the
1.3232 +** zSql string ends at either the first '\000' or '\u0000' character or
1.3233 +** the nByte-th byte, whichever comes first. If the caller knows
1.3234 +** that the supplied string is nul-terminated, then there is a small
1.3235 +** performance advantage to be gained by passing an nByte parameter that
1.3236 +** is equal to the number of bytes in the input string <i>including</i>
1.3237 +** the nul-terminator bytes as this saves SQLite from having to
1.3238 +** make a copy of the input string.
1.3239 +**
1.3240 +** ^If pzTail is not NULL then *pzTail is made to point to the first byte
1.3241 +** past the end of the first SQL statement in zSql. These routines only
1.3242 +** compile the first statement in zSql, so *pzTail is left pointing to
1.3243 +** what remains uncompiled.
1.3244 +**
1.3245 +** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
1.3246 +** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
1.3247 +** to NULL. ^If the input text contains no SQL (if the input is an empty
1.3248 +** string or a comment) then *ppStmt is set to NULL.
1.3249 +** The calling procedure is responsible for deleting the compiled
1.3250 +** SQL statement using [sqlite3_finalize()] after it has finished with it.
1.3251 +** ppStmt may not be NULL.
1.3252 +**
1.3253 +** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
1.3254 +** otherwise an [error code] is returned.
1.3255 +**
1.3256 +** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
1.3257 +** recommended for all new programs. The two older interfaces are retained
1.3258 +** for backwards compatibility, but their use is discouraged.
1.3259 +** ^In the "v2" interfaces, the prepared statement
1.3260 +** that is returned (the [sqlite3_stmt] object) contains a copy of the
1.3261 +** original SQL text. This causes the [sqlite3_step()] interface to
1.3262 +** behave differently in three ways:
1.3263 +**
1.3264 +** <ol>
1.3265 +** <li>
1.3266 +** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
1.3267 +** always used to do, [sqlite3_step()] will automatically recompile the SQL
1.3268 +** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
1.3269 +** retries will occur before sqlite3_step() gives up and returns an error.
1.3270 +** </li>
1.3271 +**
1.3272 +** <li>
1.3273 +** ^When an error occurs, [sqlite3_step()] will return one of the detailed
1.3274 +** [error codes] or [extended error codes]. ^The legacy behavior was that
1.3275 +** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
1.3276 +** and the application would have to make a second call to [sqlite3_reset()]
1.3277 +** in order to find the underlying cause of the problem. With the "v2" prepare
1.3278 +** interfaces, the underlying reason for the error is returned immediately.
1.3279 +** </li>
1.3280 +**
1.3281 +** <li>
1.3282 +** ^If the specific value bound to [parameter | host parameter] in the
1.3283 +** WHERE clause might influence the choice of query plan for a statement,
1.3284 +** then the statement will be automatically recompiled, as if there had been
1.3285 +** a schema change, on the first [sqlite3_step()] call following any change
1.3286 +** to the [sqlite3_bind_text | bindings] of that [parameter].
1.3287 +** ^The specific value of WHERE-clause [parameter] might influence the
1.3288 +** choice of query plan if the parameter is the left-hand side of a [LIKE]
1.3289 +** or [GLOB] operator or if the parameter is compared to an indexed column
1.3290 +** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
1.3291 +** </li>
1.3292 +** </ol>
1.3293 +*/
1.3294 +SQLITE_API int sqlite3_prepare(
1.3295 + sqlite3 *db, /* Database handle */
1.3296 + const char *zSql, /* SQL statement, UTF-8 encoded */
1.3297 + int nByte, /* Maximum length of zSql in bytes. */
1.3298 + sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1.3299 + const char **pzTail /* OUT: Pointer to unused portion of zSql */
1.3300 +);
1.3301 +SQLITE_API int sqlite3_prepare_v2(
1.3302 + sqlite3 *db, /* Database handle */
1.3303 + const char *zSql, /* SQL statement, UTF-8 encoded */
1.3304 + int nByte, /* Maximum length of zSql in bytes. */
1.3305 + sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1.3306 + const char **pzTail /* OUT: Pointer to unused portion of zSql */
1.3307 +);
1.3308 +SQLITE_API int sqlite3_prepare16(
1.3309 + sqlite3 *db, /* Database handle */
1.3310 + const void *zSql, /* SQL statement, UTF-16 encoded */
1.3311 + int nByte, /* Maximum length of zSql in bytes. */
1.3312 + sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1.3313 + const void **pzTail /* OUT: Pointer to unused portion of zSql */
1.3314 +);
1.3315 +SQLITE_API int sqlite3_prepare16_v2(
1.3316 + sqlite3 *db, /* Database handle */
1.3317 + const void *zSql, /* SQL statement, UTF-16 encoded */
1.3318 + int nByte, /* Maximum length of zSql in bytes. */
1.3319 + sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1.3320 + const void **pzTail /* OUT: Pointer to unused portion of zSql */
1.3321 +);
1.3322 +
1.3323 +/*
1.3324 +** CAPI3REF: Retrieving Statement SQL
1.3325 +**
1.3326 +** ^This interface can be used to retrieve a saved copy of the original
1.3327 +** SQL text used to create a [prepared statement] if that statement was
1.3328 +** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
1.3329 +*/
1.3330 +SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
1.3331 +
1.3332 +/*
1.3333 +** CAPI3REF: Determine If An SQL Statement Writes The Database
1.3334 +**
1.3335 +** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
1.3336 +** and only if the [prepared statement] X makes no direct changes to
1.3337 +** the content of the database file.
1.3338 +**
1.3339 +** Note that [application-defined SQL functions] or
1.3340 +** [virtual tables] might change the database indirectly as a side effect.
1.3341 +** ^(For example, if an application defines a function "eval()" that
1.3342 +** calls [sqlite3_exec()], then the following SQL statement would
1.3343 +** change the database file through side-effects:
1.3344 +**
1.3345 +** <blockquote><pre>
1.3346 +** SELECT eval('DELETE FROM t1') FROM t2;
1.3347 +** </pre></blockquote>
1.3348 +**
1.3349 +** But because the [SELECT] statement does not change the database file
1.3350 +** directly, sqlite3_stmt_readonly() would still return true.)^
1.3351 +**
1.3352 +** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
1.3353 +** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
1.3354 +** since the statements themselves do not actually modify the database but
1.3355 +** rather they control the timing of when other statements modify the
1.3356 +** database. ^The [ATTACH] and [DETACH] statements also cause
1.3357 +** sqlite3_stmt_readonly() to return true since, while those statements
1.3358 +** change the configuration of a database connection, they do not make
1.3359 +** changes to the content of the database files on disk.
1.3360 +*/
1.3361 +SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
1.3362 +
1.3363 +/*
1.3364 +** CAPI3REF: Determine If A Prepared Statement Has Been Reset
1.3365 +**
1.3366 +** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
1.3367 +** [prepared statement] S has been stepped at least once using
1.3368 +** [sqlite3_step(S)] but has not run to completion and/or has not
1.3369 +** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
1.3370 +** interface returns false if S is a NULL pointer. If S is not a
1.3371 +** NULL pointer and is not a pointer to a valid [prepared statement]
1.3372 +** object, then the behavior is undefined and probably undesirable.
1.3373 +**
1.3374 +** This interface can be used in combination [sqlite3_next_stmt()]
1.3375 +** to locate all prepared statements associated with a database
1.3376 +** connection that are in need of being reset. This can be used,
1.3377 +** for example, in diagnostic routines to search for prepared
1.3378 +** statements that are holding a transaction open.
1.3379 +*/
1.3380 +SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
1.3381 +
1.3382 +/*
1.3383 +** CAPI3REF: Dynamically Typed Value Object
1.3384 +** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
1.3385 +**
1.3386 +** SQLite uses the sqlite3_value object to represent all values
1.3387 +** that can be stored in a database table. SQLite uses dynamic typing
1.3388 +** for the values it stores. ^Values stored in sqlite3_value objects
1.3389 +** can be integers, floating point values, strings, BLOBs, or NULL.
1.3390 +**
1.3391 +** An sqlite3_value object may be either "protected" or "unprotected".
1.3392 +** Some interfaces require a protected sqlite3_value. Other interfaces
1.3393 +** will accept either a protected or an unprotected sqlite3_value.
1.3394 +** Every interface that accepts sqlite3_value arguments specifies
1.3395 +** whether or not it requires a protected sqlite3_value.
1.3396 +**
1.3397 +** The terms "protected" and "unprotected" refer to whether or not
1.3398 +** a mutex is held. An internal mutex is held for a protected
1.3399 +** sqlite3_value object but no mutex is held for an unprotected
1.3400 +** sqlite3_value object. If SQLite is compiled to be single-threaded
1.3401 +** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
1.3402 +** or if SQLite is run in one of reduced mutex modes
1.3403 +** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
1.3404 +** then there is no distinction between protected and unprotected
1.3405 +** sqlite3_value objects and they can be used interchangeably. However,
1.3406 +** for maximum code portability it is recommended that applications
1.3407 +** still make the distinction between protected and unprotected
1.3408 +** sqlite3_value objects even when not strictly required.
1.3409 +**
1.3410 +** ^The sqlite3_value objects that are passed as parameters into the
1.3411 +** implementation of [application-defined SQL functions] are protected.
1.3412 +** ^The sqlite3_value object returned by
1.3413 +** [sqlite3_column_value()] is unprotected.
1.3414 +** Unprotected sqlite3_value objects may only be used with
1.3415 +** [sqlite3_result_value()] and [sqlite3_bind_value()].
1.3416 +** The [sqlite3_value_blob | sqlite3_value_type()] family of
1.3417 +** interfaces require protected sqlite3_value objects.
1.3418 +*/
1.3419 +typedef struct Mem sqlite3_value;
1.3420 +
1.3421 +/*
1.3422 +** CAPI3REF: SQL Function Context Object
1.3423 +**
1.3424 +** The context in which an SQL function executes is stored in an
1.3425 +** sqlite3_context object. ^A pointer to an sqlite3_context object
1.3426 +** is always first parameter to [application-defined SQL functions].
1.3427 +** The application-defined SQL function implementation will pass this
1.3428 +** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
1.3429 +** [sqlite3_aggregate_context()], [sqlite3_user_data()],
1.3430 +** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
1.3431 +** and/or [sqlite3_set_auxdata()].
1.3432 +*/
1.3433 +typedef struct sqlite3_context sqlite3_context;
1.3434 +
1.3435 +/*
1.3436 +** CAPI3REF: Binding Values To Prepared Statements
1.3437 +** KEYWORDS: {host parameter} {host parameters} {host parameter name}
1.3438 +** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
1.3439 +**
1.3440 +** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
1.3441 +** literals may be replaced by a [parameter] that matches one of following
1.3442 +** templates:
1.3443 +**
1.3444 +** <ul>
1.3445 +** <li> ?
1.3446 +** <li> ?NNN
1.3447 +** <li> :VVV
1.3448 +** <li> @VVV
1.3449 +** <li> $VVV
1.3450 +** </ul>
1.3451 +**
1.3452 +** In the templates above, NNN represents an integer literal,
1.3453 +** and VVV represents an alphanumeric identifier.)^ ^The values of these
1.3454 +** parameters (also called "host parameter names" or "SQL parameters")
1.3455 +** can be set using the sqlite3_bind_*() routines defined here.
1.3456 +**
1.3457 +** ^The first argument to the sqlite3_bind_*() routines is always
1.3458 +** a pointer to the [sqlite3_stmt] object returned from
1.3459 +** [sqlite3_prepare_v2()] or its variants.
1.3460 +**
1.3461 +** ^The second argument is the index of the SQL parameter to be set.
1.3462 +** ^The leftmost SQL parameter has an index of 1. ^When the same named
1.3463 +** SQL parameter is used more than once, second and subsequent
1.3464 +** occurrences have the same index as the first occurrence.
1.3465 +** ^The index for named parameters can be looked up using the
1.3466 +** [sqlite3_bind_parameter_index()] API if desired. ^The index
1.3467 +** for "?NNN" parameters is the value of NNN.
1.3468 +** ^The NNN value must be between 1 and the [sqlite3_limit()]
1.3469 +** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
1.3470 +**
1.3471 +** ^The third argument is the value to bind to the parameter.
1.3472 +** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
1.3473 +** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
1.3474 +** is ignored and the end result is the same as sqlite3_bind_null().
1.3475 +**
1.3476 +** ^(In those routines that have a fourth argument, its value is the
1.3477 +** number of bytes in the parameter. To be clear: the value is the
1.3478 +** number of <u>bytes</u> in the value, not the number of characters.)^
1.3479 +** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
1.3480 +** is negative, then the length of the string is
1.3481 +** the number of bytes up to the first zero terminator.
1.3482 +** If the fourth parameter to sqlite3_bind_blob() is negative, then
1.3483 +** the behavior is undefined.
1.3484 +** If a non-negative fourth parameter is provided to sqlite3_bind_text()
1.3485 +** or sqlite3_bind_text16() then that parameter must be the byte offset
1.3486 +** where the NUL terminator would occur assuming the string were NUL
1.3487 +** terminated. If any NUL characters occur at byte offsets less than
1.3488 +** the value of the fourth parameter then the resulting string value will
1.3489 +** contain embedded NULs. The result of expressions involving strings
1.3490 +** with embedded NULs is undefined.
1.3491 +**
1.3492 +** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
1.3493 +** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
1.3494 +** string after SQLite has finished with it. ^The destructor is called
1.3495 +** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
1.3496 +** sqlite3_bind_text(), or sqlite3_bind_text16() fails.
1.3497 +** ^If the fifth argument is
1.3498 +** the special value [SQLITE_STATIC], then SQLite assumes that the
1.3499 +** information is in static, unmanaged space and does not need to be freed.
1.3500 +** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
1.3501 +** SQLite makes its own private copy of the data immediately, before
1.3502 +** the sqlite3_bind_*() routine returns.
1.3503 +**
1.3504 +** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
1.3505 +** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
1.3506 +** (just an integer to hold its size) while it is being processed.
1.3507 +** Zeroblobs are intended to serve as placeholders for BLOBs whose
1.3508 +** content is later written using
1.3509 +** [sqlite3_blob_open | incremental BLOB I/O] routines.
1.3510 +** ^A negative value for the zeroblob results in a zero-length BLOB.
1.3511 +**
1.3512 +** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
1.3513 +** for the [prepared statement] or with a prepared statement for which
1.3514 +** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
1.3515 +** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
1.3516 +** routine is passed a [prepared statement] that has been finalized, the
1.3517 +** result is undefined and probably harmful.
1.3518 +**
1.3519 +** ^Bindings are not cleared by the [sqlite3_reset()] routine.
1.3520 +** ^Unbound parameters are interpreted as NULL.
1.3521 +**
1.3522 +** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
1.3523 +** [error code] if anything goes wrong.
1.3524 +** ^[SQLITE_RANGE] is returned if the parameter
1.3525 +** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
1.3526 +**
1.3527 +** See also: [sqlite3_bind_parameter_count()],
1.3528 +** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
1.3529 +*/
1.3530 +SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
1.3531 +SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
1.3532 +SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
1.3533 +SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
1.3534 +SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
1.3535 +SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
1.3536 +SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
1.3537 +SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
1.3538 +SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
1.3539 +
1.3540 +/*
1.3541 +** CAPI3REF: Number Of SQL Parameters
1.3542 +**
1.3543 +** ^This routine can be used to find the number of [SQL parameters]
1.3544 +** in a [prepared statement]. SQL parameters are tokens of the
1.3545 +** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
1.3546 +** placeholders for values that are [sqlite3_bind_blob | bound]
1.3547 +** to the parameters at a later time.
1.3548 +**
1.3549 +** ^(This routine actually returns the index of the largest (rightmost)
1.3550 +** parameter. For all forms except ?NNN, this will correspond to the
1.3551 +** number of unique parameters. If parameters of the ?NNN form are used,
1.3552 +** there may be gaps in the list.)^
1.3553 +**
1.3554 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
1.3555 +** [sqlite3_bind_parameter_name()], and
1.3556 +** [sqlite3_bind_parameter_index()].
1.3557 +*/
1.3558 +SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
1.3559 +
1.3560 +/*
1.3561 +** CAPI3REF: Name Of A Host Parameter
1.3562 +**
1.3563 +** ^The sqlite3_bind_parameter_name(P,N) interface returns
1.3564 +** the name of the N-th [SQL parameter] in the [prepared statement] P.
1.3565 +** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
1.3566 +** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
1.3567 +** respectively.
1.3568 +** In other words, the initial ":" or "$" or "@" or "?"
1.3569 +** is included as part of the name.)^
1.3570 +** ^Parameters of the form "?" without a following integer have no name
1.3571 +** and are referred to as "nameless" or "anonymous parameters".
1.3572 +**
1.3573 +** ^The first host parameter has an index of 1, not 0.
1.3574 +**
1.3575 +** ^If the value N is out of range or if the N-th parameter is
1.3576 +** nameless, then NULL is returned. ^The returned string is
1.3577 +** always in UTF-8 encoding even if the named parameter was
1.3578 +** originally specified as UTF-16 in [sqlite3_prepare16()] or
1.3579 +** [sqlite3_prepare16_v2()].
1.3580 +**
1.3581 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
1.3582 +** [sqlite3_bind_parameter_count()], and
1.3583 +** [sqlite3_bind_parameter_index()].
1.3584 +*/
1.3585 +SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
1.3586 +
1.3587 +/*
1.3588 +** CAPI3REF: Index Of A Parameter With A Given Name
1.3589 +**
1.3590 +** ^Return the index of an SQL parameter given its name. ^The
1.3591 +** index value returned is suitable for use as the second
1.3592 +** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
1.3593 +** is returned if no matching parameter is found. ^The parameter
1.3594 +** name must be given in UTF-8 even if the original statement
1.3595 +** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
1.3596 +**
1.3597 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
1.3598 +** [sqlite3_bind_parameter_count()], and
1.3599 +** [sqlite3_bind_parameter_index()].
1.3600 +*/
1.3601 +SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
1.3602 +
1.3603 +/*
1.3604 +** CAPI3REF: Reset All Bindings On A Prepared Statement
1.3605 +**
1.3606 +** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
1.3607 +** the [sqlite3_bind_blob | bindings] on a [prepared statement].
1.3608 +** ^Use this routine to reset all host parameters to NULL.
1.3609 +*/
1.3610 +SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
1.3611 +
1.3612 +/*
1.3613 +** CAPI3REF: Number Of Columns In A Result Set
1.3614 +**
1.3615 +** ^Return the number of columns in the result set returned by the
1.3616 +** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
1.3617 +** statement that does not return data (for example an [UPDATE]).
1.3618 +**
1.3619 +** See also: [sqlite3_data_count()]
1.3620 +*/
1.3621 +SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
1.3622 +
1.3623 +/*
1.3624 +** CAPI3REF: Column Names In A Result Set
1.3625 +**
1.3626 +** ^These routines return the name assigned to a particular column
1.3627 +** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
1.3628 +** interface returns a pointer to a zero-terminated UTF-8 string
1.3629 +** and sqlite3_column_name16() returns a pointer to a zero-terminated
1.3630 +** UTF-16 string. ^The first parameter is the [prepared statement]
1.3631 +** that implements the [SELECT] statement. ^The second parameter is the
1.3632 +** column number. ^The leftmost column is number 0.
1.3633 +**
1.3634 +** ^The returned string pointer is valid until either the [prepared statement]
1.3635 +** is destroyed by [sqlite3_finalize()] or until the statement is automatically
1.3636 +** reprepared by the first call to [sqlite3_step()] for a particular run
1.3637 +** or until the next call to
1.3638 +** sqlite3_column_name() or sqlite3_column_name16() on the same column.
1.3639 +**
1.3640 +** ^If sqlite3_malloc() fails during the processing of either routine
1.3641 +** (for example during a conversion from UTF-8 to UTF-16) then a
1.3642 +** NULL pointer is returned.
1.3643 +**
1.3644 +** ^The name of a result column is the value of the "AS" clause for
1.3645 +** that column, if there is an AS clause. If there is no AS clause
1.3646 +** then the name of the column is unspecified and may change from
1.3647 +** one release of SQLite to the next.
1.3648 +*/
1.3649 +SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
1.3650 +SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
1.3651 +
1.3652 +/*
1.3653 +** CAPI3REF: Source Of Data In A Query Result
1.3654 +**
1.3655 +** ^These routines provide a means to determine the database, table, and
1.3656 +** table column that is the origin of a particular result column in
1.3657 +** [SELECT] statement.
1.3658 +** ^The name of the database or table or column can be returned as
1.3659 +** either a UTF-8 or UTF-16 string. ^The _database_ routines return
1.3660 +** the database name, the _table_ routines return the table name, and
1.3661 +** the origin_ routines return the column name.
1.3662 +** ^The returned string is valid until the [prepared statement] is destroyed
1.3663 +** using [sqlite3_finalize()] or until the statement is automatically
1.3664 +** reprepared by the first call to [sqlite3_step()] for a particular run
1.3665 +** or until the same information is requested
1.3666 +** again in a different encoding.
1.3667 +**
1.3668 +** ^The names returned are the original un-aliased names of the
1.3669 +** database, table, and column.
1.3670 +**
1.3671 +** ^The first argument to these interfaces is a [prepared statement].
1.3672 +** ^These functions return information about the Nth result column returned by
1.3673 +** the statement, where N is the second function argument.
1.3674 +** ^The left-most column is column 0 for these routines.
1.3675 +**
1.3676 +** ^If the Nth column returned by the statement is an expression or
1.3677 +** subquery and is not a column value, then all of these functions return
1.3678 +** NULL. ^These routine might also return NULL if a memory allocation error
1.3679 +** occurs. ^Otherwise, they return the name of the attached database, table,
1.3680 +** or column that query result column was extracted from.
1.3681 +**
1.3682 +** ^As with all other SQLite APIs, those whose names end with "16" return
1.3683 +** UTF-16 encoded strings and the other functions return UTF-8.
1.3684 +**
1.3685 +** ^These APIs are only available if the library was compiled with the
1.3686 +** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
1.3687 +**
1.3688 +** If two or more threads call one or more of these routines against the same
1.3689 +** prepared statement and column at the same time then the results are
1.3690 +** undefined.
1.3691 +**
1.3692 +** If two or more threads call one or more
1.3693 +** [sqlite3_column_database_name | column metadata interfaces]
1.3694 +** for the same [prepared statement] and result column
1.3695 +** at the same time then the results are undefined.
1.3696 +*/
1.3697 +SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
1.3698 +SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
1.3699 +SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
1.3700 +SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
1.3701 +SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
1.3702 +SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
1.3703 +
1.3704 +/*
1.3705 +** CAPI3REF: Declared Datatype Of A Query Result
1.3706 +**
1.3707 +** ^(The first parameter is a [prepared statement].
1.3708 +** If this statement is a [SELECT] statement and the Nth column of the
1.3709 +** returned result set of that [SELECT] is a table column (not an
1.3710 +** expression or subquery) then the declared type of the table
1.3711 +** column is returned.)^ ^If the Nth column of the result set is an
1.3712 +** expression or subquery, then a NULL pointer is returned.
1.3713 +** ^The returned string is always UTF-8 encoded.
1.3714 +**
1.3715 +** ^(For example, given the database schema:
1.3716 +**
1.3717 +** CREATE TABLE t1(c1 VARIANT);
1.3718 +**
1.3719 +** and the following statement to be compiled:
1.3720 +**
1.3721 +** SELECT c1 + 1, c1 FROM t1;
1.3722 +**
1.3723 +** this routine would return the string "VARIANT" for the second result
1.3724 +** column (i==1), and a NULL pointer for the first result column (i==0).)^
1.3725 +**
1.3726 +** ^SQLite uses dynamic run-time typing. ^So just because a column
1.3727 +** is declared to contain a particular type does not mean that the
1.3728 +** data stored in that column is of the declared type. SQLite is
1.3729 +** strongly typed, but the typing is dynamic not static. ^Type
1.3730 +** is associated with individual values, not with the containers
1.3731 +** used to hold those values.
1.3732 +*/
1.3733 +SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
1.3734 +SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
1.3735 +
1.3736 +/*
1.3737 +** CAPI3REF: Evaluate An SQL Statement
1.3738 +**
1.3739 +** After a [prepared statement] has been prepared using either
1.3740 +** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
1.3741 +** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
1.3742 +** must be called one or more times to evaluate the statement.
1.3743 +**
1.3744 +** The details of the behavior of the sqlite3_step() interface depend
1.3745 +** on whether the statement was prepared using the newer "v2" interface
1.3746 +** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
1.3747 +** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
1.3748 +** new "v2" interface is recommended for new applications but the legacy
1.3749 +** interface will continue to be supported.
1.3750 +**
1.3751 +** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
1.3752 +** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
1.3753 +** ^With the "v2" interface, any of the other [result codes] or
1.3754 +** [extended result codes] might be returned as well.
1.3755 +**
1.3756 +** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
1.3757 +** database locks it needs to do its job. ^If the statement is a [COMMIT]
1.3758 +** or occurs outside of an explicit transaction, then you can retry the
1.3759 +** statement. If the statement is not a [COMMIT] and occurs within an
1.3760 +** explicit transaction then you should rollback the transaction before
1.3761 +** continuing.
1.3762 +**
1.3763 +** ^[SQLITE_DONE] means that the statement has finished executing
1.3764 +** successfully. sqlite3_step() should not be called again on this virtual
1.3765 +** machine without first calling [sqlite3_reset()] to reset the virtual
1.3766 +** machine back to its initial state.
1.3767 +**
1.3768 +** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
1.3769 +** is returned each time a new row of data is ready for processing by the
1.3770 +** caller. The values may be accessed using the [column access functions].
1.3771 +** sqlite3_step() is called again to retrieve the next row of data.
1.3772 +**
1.3773 +** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
1.3774 +** violation) has occurred. sqlite3_step() should not be called again on
1.3775 +** the VM. More information may be found by calling [sqlite3_errmsg()].
1.3776 +** ^With the legacy interface, a more specific error code (for example,
1.3777 +** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
1.3778 +** can be obtained by calling [sqlite3_reset()] on the
1.3779 +** [prepared statement]. ^In the "v2" interface,
1.3780 +** the more specific error code is returned directly by sqlite3_step().
1.3781 +**
1.3782 +** [SQLITE_MISUSE] means that the this routine was called inappropriately.
1.3783 +** Perhaps it was called on a [prepared statement] that has
1.3784 +** already been [sqlite3_finalize | finalized] or on one that had
1.3785 +** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
1.3786 +** be the case that the same database connection is being used by two or
1.3787 +** more threads at the same moment in time.
1.3788 +**
1.3789 +** For all versions of SQLite up to and including 3.6.23.1, a call to
1.3790 +** [sqlite3_reset()] was required after sqlite3_step() returned anything
1.3791 +** other than [SQLITE_ROW] before any subsequent invocation of
1.3792 +** sqlite3_step(). Failure to reset the prepared statement using
1.3793 +** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
1.3794 +** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began
1.3795 +** calling [sqlite3_reset()] automatically in this circumstance rather
1.3796 +** than returning [SQLITE_MISUSE]. This is not considered a compatibility
1.3797 +** break because any application that ever receives an SQLITE_MISUSE error
1.3798 +** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
1.3799 +** can be used to restore the legacy behavior.
1.3800 +**
1.3801 +** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
1.3802 +** API always returns a generic error code, [SQLITE_ERROR], following any
1.3803 +** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
1.3804 +** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
1.3805 +** specific [error codes] that better describes the error.
1.3806 +** We admit that this is a goofy design. The problem has been fixed
1.3807 +** with the "v2" interface. If you prepare all of your SQL statements
1.3808 +** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
1.3809 +** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
1.3810 +** then the more specific [error codes] are returned directly
1.3811 +** by sqlite3_step(). The use of the "v2" interface is recommended.
1.3812 +*/
1.3813 +SQLITE_API int sqlite3_step(sqlite3_stmt*);
1.3814 +
1.3815 +/*
1.3816 +** CAPI3REF: Number of columns in a result set
1.3817 +**
1.3818 +** ^The sqlite3_data_count(P) interface returns the number of columns in the
1.3819 +** current row of the result set of [prepared statement] P.
1.3820 +** ^If prepared statement P does not have results ready to return
1.3821 +** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
1.3822 +** interfaces) then sqlite3_data_count(P) returns 0.
1.3823 +** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
1.3824 +** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
1.3825 +** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
1.3826 +** will return non-zero if previous call to [sqlite3_step](P) returned
1.3827 +** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
1.3828 +** where it always returns zero since each step of that multi-step
1.3829 +** pragma returns 0 columns of data.
1.3830 +**
1.3831 +** See also: [sqlite3_column_count()]
1.3832 +*/
1.3833 +SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
1.3834 +
1.3835 +/*
1.3836 +** CAPI3REF: Fundamental Datatypes
1.3837 +** KEYWORDS: SQLITE_TEXT
1.3838 +**
1.3839 +** ^(Every value in SQLite has one of five fundamental datatypes:
1.3840 +**
1.3841 +** <ul>
1.3842 +** <li> 64-bit signed integer
1.3843 +** <li> 64-bit IEEE floating point number
1.3844 +** <li> string
1.3845 +** <li> BLOB
1.3846 +** <li> NULL
1.3847 +** </ul>)^
1.3848 +**
1.3849 +** These constants are codes for each of those types.
1.3850 +**
1.3851 +** Note that the SQLITE_TEXT constant was also used in SQLite version 2
1.3852 +** for a completely different meaning. Software that links against both
1.3853 +** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
1.3854 +** SQLITE_TEXT.
1.3855 +*/
1.3856 +#define SQLITE_INTEGER 1
1.3857 +#define SQLITE_FLOAT 2
1.3858 +#define SQLITE_BLOB 4
1.3859 +#define SQLITE_NULL 5
1.3860 +#ifdef SQLITE_TEXT
1.3861 +# undef SQLITE_TEXT
1.3862 +#else
1.3863 +# define SQLITE_TEXT 3
1.3864 +#endif
1.3865 +#define SQLITE3_TEXT 3
1.3866 +
1.3867 +/*
1.3868 +** CAPI3REF: Result Values From A Query
1.3869 +** KEYWORDS: {column access functions}
1.3870 +**
1.3871 +** These routines form the "result set" interface.
1.3872 +**
1.3873 +** ^These routines return information about a single column of the current
1.3874 +** result row of a query. ^In every case the first argument is a pointer
1.3875 +** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
1.3876 +** that was returned from [sqlite3_prepare_v2()] or one of its variants)
1.3877 +** and the second argument is the index of the column for which information
1.3878 +** should be returned. ^The leftmost column of the result set has the index 0.
1.3879 +** ^The number of columns in the result can be determined using
1.3880 +** [sqlite3_column_count()].
1.3881 +**
1.3882 +** If the SQL statement does not currently point to a valid row, or if the
1.3883 +** column index is out of range, the result is undefined.
1.3884 +** These routines may only be called when the most recent call to
1.3885 +** [sqlite3_step()] has returned [SQLITE_ROW] and neither
1.3886 +** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
1.3887 +** If any of these routines are called after [sqlite3_reset()] or
1.3888 +** [sqlite3_finalize()] or after [sqlite3_step()] has returned
1.3889 +** something other than [SQLITE_ROW], the results are undefined.
1.3890 +** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
1.3891 +** are called from a different thread while any of these routines
1.3892 +** are pending, then the results are undefined.
1.3893 +**
1.3894 +** ^The sqlite3_column_type() routine returns the
1.3895 +** [SQLITE_INTEGER | datatype code] for the initial data type
1.3896 +** of the result column. ^The returned value is one of [SQLITE_INTEGER],
1.3897 +** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
1.3898 +** returned by sqlite3_column_type() is only meaningful if no type
1.3899 +** conversions have occurred as described below. After a type conversion,
1.3900 +** the value returned by sqlite3_column_type() is undefined. Future
1.3901 +** versions of SQLite may change the behavior of sqlite3_column_type()
1.3902 +** following a type conversion.
1.3903 +**
1.3904 +** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
1.3905 +** routine returns the number of bytes in that BLOB or string.
1.3906 +** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
1.3907 +** the string to UTF-8 and then returns the number of bytes.
1.3908 +** ^If the result is a numeric value then sqlite3_column_bytes() uses
1.3909 +** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
1.3910 +** the number of bytes in that string.
1.3911 +** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
1.3912 +**
1.3913 +** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
1.3914 +** routine returns the number of bytes in that BLOB or string.
1.3915 +** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
1.3916 +** the string to UTF-16 and then returns the number of bytes.
1.3917 +** ^If the result is a numeric value then sqlite3_column_bytes16() uses
1.3918 +** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
1.3919 +** the number of bytes in that string.
1.3920 +** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
1.3921 +**
1.3922 +** ^The values returned by [sqlite3_column_bytes()] and
1.3923 +** [sqlite3_column_bytes16()] do not include the zero terminators at the end
1.3924 +** of the string. ^For clarity: the values returned by
1.3925 +** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
1.3926 +** bytes in the string, not the number of characters.
1.3927 +**
1.3928 +** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
1.3929 +** even empty strings, are always zero-terminated. ^The return
1.3930 +** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
1.3931 +**
1.3932 +** ^The object returned by [sqlite3_column_value()] is an
1.3933 +** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
1.3934 +** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
1.3935 +** If the [unprotected sqlite3_value] object returned by
1.3936 +** [sqlite3_column_value()] is used in any other way, including calls
1.3937 +** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
1.3938 +** or [sqlite3_value_bytes()], then the behavior is undefined.
1.3939 +**
1.3940 +** These routines attempt to convert the value where appropriate. ^For
1.3941 +** example, if the internal representation is FLOAT and a text result
1.3942 +** is requested, [sqlite3_snprintf()] is used internally to perform the
1.3943 +** conversion automatically. ^(The following table details the conversions
1.3944 +** that are applied:
1.3945 +**
1.3946 +** <blockquote>
1.3947 +** <table border="1">
1.3948 +** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
1.3949 +**
1.3950 +** <tr><td> NULL <td> INTEGER <td> Result is 0
1.3951 +** <tr><td> NULL <td> FLOAT <td> Result is 0.0
1.3952 +** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer
1.3953 +** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer
1.3954 +** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
1.3955 +** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
1.3956 +** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
1.3957 +** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER
1.3958 +** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
1.3959 +** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB
1.3960 +** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER
1.3961 +** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL
1.3962 +** <tr><td> TEXT <td> BLOB <td> No change
1.3963 +** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER
1.3964 +** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL
1.3965 +** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
1.3966 +** </table>
1.3967 +** </blockquote>)^
1.3968 +**
1.3969 +** The table above makes reference to standard C library functions atoi()
1.3970 +** and atof(). SQLite does not really use these functions. It has its
1.3971 +** own equivalent internal routines. The atoi() and atof() names are
1.3972 +** used in the table for brevity and because they are familiar to most
1.3973 +** C programmers.
1.3974 +**
1.3975 +** Note that when type conversions occur, pointers returned by prior
1.3976 +** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
1.3977 +** sqlite3_column_text16() may be invalidated.
1.3978 +** Type conversions and pointer invalidations might occur
1.3979 +** in the following cases:
1.3980 +**
1.3981 +** <ul>
1.3982 +** <li> The initial content is a BLOB and sqlite3_column_text() or
1.3983 +** sqlite3_column_text16() is called. A zero-terminator might
1.3984 +** need to be added to the string.</li>
1.3985 +** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
1.3986 +** sqlite3_column_text16() is called. The content must be converted
1.3987 +** to UTF-16.</li>
1.3988 +** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
1.3989 +** sqlite3_column_text() is called. The content must be converted
1.3990 +** to UTF-8.</li>
1.3991 +** </ul>
1.3992 +**
1.3993 +** ^Conversions between UTF-16be and UTF-16le are always done in place and do
1.3994 +** not invalidate a prior pointer, though of course the content of the buffer
1.3995 +** that the prior pointer references will have been modified. Other kinds
1.3996 +** of conversion are done in place when it is possible, but sometimes they
1.3997 +** are not possible and in those cases prior pointers are invalidated.
1.3998 +**
1.3999 +** The safest and easiest to remember policy is to invoke these routines
1.4000 +** in one of the following ways:
1.4001 +**
1.4002 +** <ul>
1.4003 +** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
1.4004 +** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
1.4005 +** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
1.4006 +** </ul>
1.4007 +**
1.4008 +** In other words, you should call sqlite3_column_text(),
1.4009 +** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
1.4010 +** into the desired format, then invoke sqlite3_column_bytes() or
1.4011 +** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
1.4012 +** to sqlite3_column_text() or sqlite3_column_blob() with calls to
1.4013 +** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
1.4014 +** with calls to sqlite3_column_bytes().
1.4015 +**
1.4016 +** ^The pointers returned are valid until a type conversion occurs as
1.4017 +** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
1.4018 +** [sqlite3_finalize()] is called. ^The memory space used to hold strings
1.4019 +** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
1.4020 +** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
1.4021 +** [sqlite3_free()].
1.4022 +**
1.4023 +** ^(If a memory allocation error occurs during the evaluation of any
1.4024 +** of these routines, a default value is returned. The default value
1.4025 +** is either the integer 0, the floating point number 0.0, or a NULL
1.4026 +** pointer. Subsequent calls to [sqlite3_errcode()] will return
1.4027 +** [SQLITE_NOMEM].)^
1.4028 +*/
1.4029 +SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
1.4030 +SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
1.4031 +SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
1.4032 +SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
1.4033 +SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
1.4034 +SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
1.4035 +SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
1.4036 +SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
1.4037 +SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
1.4038 +SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
1.4039 +
1.4040 +/*
1.4041 +** CAPI3REF: Destroy A Prepared Statement Object
1.4042 +**
1.4043 +** ^The sqlite3_finalize() function is called to delete a [prepared statement].
1.4044 +** ^If the most recent evaluation of the statement encountered no errors
1.4045 +** or if the statement is never been evaluated, then sqlite3_finalize() returns
1.4046 +** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
1.4047 +** sqlite3_finalize(S) returns the appropriate [error code] or
1.4048 +** [extended error code].
1.4049 +**
1.4050 +** ^The sqlite3_finalize(S) routine can be called at any point during
1.4051 +** the life cycle of [prepared statement] S:
1.4052 +** before statement S is ever evaluated, after
1.4053 +** one or more calls to [sqlite3_reset()], or after any call
1.4054 +** to [sqlite3_step()] regardless of whether or not the statement has
1.4055 +** completed execution.
1.4056 +**
1.4057 +** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
1.4058 +**
1.4059 +** The application must finalize every [prepared statement] in order to avoid
1.4060 +** resource leaks. It is a grievous error for the application to try to use
1.4061 +** a prepared statement after it has been finalized. Any use of a prepared
1.4062 +** statement after it has been finalized can result in undefined and
1.4063 +** undesirable behavior such as segfaults and heap corruption.
1.4064 +*/
1.4065 +SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
1.4066 +
1.4067 +/*
1.4068 +** CAPI3REF: Reset A Prepared Statement Object
1.4069 +**
1.4070 +** The sqlite3_reset() function is called to reset a [prepared statement]
1.4071 +** object back to its initial state, ready to be re-executed.
1.4072 +** ^Any SQL statement variables that had values bound to them using
1.4073 +** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
1.4074 +** Use [sqlite3_clear_bindings()] to reset the bindings.
1.4075 +**
1.4076 +** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
1.4077 +** back to the beginning of its program.
1.4078 +**
1.4079 +** ^If the most recent call to [sqlite3_step(S)] for the
1.4080 +** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
1.4081 +** or if [sqlite3_step(S)] has never before been called on S,
1.4082 +** then [sqlite3_reset(S)] returns [SQLITE_OK].
1.4083 +**
1.4084 +** ^If the most recent call to [sqlite3_step(S)] for the
1.4085 +** [prepared statement] S indicated an error, then
1.4086 +** [sqlite3_reset(S)] returns an appropriate [error code].
1.4087 +**
1.4088 +** ^The [sqlite3_reset(S)] interface does not change the values
1.4089 +** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
1.4090 +*/
1.4091 +SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
1.4092 +
1.4093 +/*
1.4094 +** CAPI3REF: Create Or Redefine SQL Functions
1.4095 +** KEYWORDS: {function creation routines}
1.4096 +** KEYWORDS: {application-defined SQL function}
1.4097 +** KEYWORDS: {application-defined SQL functions}
1.4098 +**
1.4099 +** ^These functions (collectively known as "function creation routines")
1.4100 +** are used to add SQL functions or aggregates or to redefine the behavior
1.4101 +** of existing SQL functions or aggregates. The only differences between
1.4102 +** these routines are the text encoding expected for
1.4103 +** the second parameter (the name of the function being created)
1.4104 +** and the presence or absence of a destructor callback for
1.4105 +** the application data pointer.
1.4106 +**
1.4107 +** ^The first parameter is the [database connection] to which the SQL
1.4108 +** function is to be added. ^If an application uses more than one database
1.4109 +** connection then application-defined SQL functions must be added
1.4110 +** to each database connection separately.
1.4111 +**
1.4112 +** ^The second parameter is the name of the SQL function to be created or
1.4113 +** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
1.4114 +** representation, exclusive of the zero-terminator. ^Note that the name
1.4115 +** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
1.4116 +** ^Any attempt to create a function with a longer name
1.4117 +** will result in [SQLITE_MISUSE] being returned.
1.4118 +**
1.4119 +** ^The third parameter (nArg)
1.4120 +** is the number of arguments that the SQL function or
1.4121 +** aggregate takes. ^If this parameter is -1, then the SQL function or
1.4122 +** aggregate may take any number of arguments between 0 and the limit
1.4123 +** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
1.4124 +** parameter is less than -1 or greater than 127 then the behavior is
1.4125 +** undefined.
1.4126 +**
1.4127 +** ^The fourth parameter, eTextRep, specifies what
1.4128 +** [SQLITE_UTF8 | text encoding] this SQL function prefers for
1.4129 +** its parameters. The application should set this parameter to
1.4130 +** [SQLITE_UTF16LE] if the function implementation invokes
1.4131 +** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
1.4132 +** implementation invokes [sqlite3_value_text16be()] on an input, or
1.4133 +** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
1.4134 +** otherwise. ^The same SQL function may be registered multiple times using
1.4135 +** different preferred text encodings, with different implementations for
1.4136 +** each encoding.
1.4137 +** ^When multiple implementations of the same function are available, SQLite
1.4138 +** will pick the one that involves the least amount of data conversion.
1.4139 +**
1.4140 +** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
1.4141 +** to signal that the function will always return the same result given
1.4142 +** the same inputs within a single SQL statement. Most SQL functions are
1.4143 +** deterministic. The built-in [random()] SQL function is an example of a
1.4144 +** function that is not deterministic. The SQLite query planner is able to
1.4145 +** perform additional optimizations on deterministic functions, so use
1.4146 +** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
1.4147 +**
1.4148 +** ^(The fifth parameter is an arbitrary pointer. The implementation of the
1.4149 +** function can gain access to this pointer using [sqlite3_user_data()].)^
1.4150 +**
1.4151 +** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
1.4152 +** pointers to C-language functions that implement the SQL function or
1.4153 +** aggregate. ^A scalar SQL function requires an implementation of the xFunc
1.4154 +** callback only; NULL pointers must be passed as the xStep and xFinal
1.4155 +** parameters. ^An aggregate SQL function requires an implementation of xStep
1.4156 +** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
1.4157 +** SQL function or aggregate, pass NULL pointers for all three function
1.4158 +** callbacks.
1.4159 +**
1.4160 +** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
1.4161 +** then it is destructor for the application data pointer.
1.4162 +** The destructor is invoked when the function is deleted, either by being
1.4163 +** overloaded or when the database connection closes.)^
1.4164 +** ^The destructor is also invoked if the call to
1.4165 +** sqlite3_create_function_v2() fails.
1.4166 +** ^When the destructor callback of the tenth parameter is invoked, it
1.4167 +** is passed a single argument which is a copy of the application data
1.4168 +** pointer which was the fifth parameter to sqlite3_create_function_v2().
1.4169 +**
1.4170 +** ^It is permitted to register multiple implementations of the same
1.4171 +** functions with the same name but with either differing numbers of
1.4172 +** arguments or differing preferred text encodings. ^SQLite will use
1.4173 +** the implementation that most closely matches the way in which the
1.4174 +** SQL function is used. ^A function implementation with a non-negative
1.4175 +** nArg parameter is a better match than a function implementation with
1.4176 +** a negative nArg. ^A function where the preferred text encoding
1.4177 +** matches the database encoding is a better
1.4178 +** match than a function where the encoding is different.
1.4179 +** ^A function where the encoding difference is between UTF16le and UTF16be
1.4180 +** is a closer match than a function where the encoding difference is
1.4181 +** between UTF8 and UTF16.
1.4182 +**
1.4183 +** ^Built-in functions may be overloaded by new application-defined functions.
1.4184 +**
1.4185 +** ^An application-defined function is permitted to call other
1.4186 +** SQLite interfaces. However, such calls must not
1.4187 +** close the database connection nor finalize or reset the prepared
1.4188 +** statement in which the function is running.
1.4189 +*/
1.4190 +SQLITE_API int sqlite3_create_function(
1.4191 + sqlite3 *db,
1.4192 + const char *zFunctionName,
1.4193 + int nArg,
1.4194 + int eTextRep,
1.4195 + void *pApp,
1.4196 + void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
1.4197 + void (*xStep)(sqlite3_context*,int,sqlite3_value**),
1.4198 + void (*xFinal)(sqlite3_context*)
1.4199 +);
1.4200 +SQLITE_API int sqlite3_create_function16(
1.4201 + sqlite3 *db,
1.4202 + const void *zFunctionName,
1.4203 + int nArg,
1.4204 + int eTextRep,
1.4205 + void *pApp,
1.4206 + void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
1.4207 + void (*xStep)(sqlite3_context*,int,sqlite3_value**),
1.4208 + void (*xFinal)(sqlite3_context*)
1.4209 +);
1.4210 +SQLITE_API int sqlite3_create_function_v2(
1.4211 + sqlite3 *db,
1.4212 + const char *zFunctionName,
1.4213 + int nArg,
1.4214 + int eTextRep,
1.4215 + void *pApp,
1.4216 + void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
1.4217 + void (*xStep)(sqlite3_context*,int,sqlite3_value**),
1.4218 + void (*xFinal)(sqlite3_context*),
1.4219 + void(*xDestroy)(void*)
1.4220 +);
1.4221 +
1.4222 +/*
1.4223 +** CAPI3REF: Text Encodings
1.4224 +**
1.4225 +** These constant define integer codes that represent the various
1.4226 +** text encodings supported by SQLite.
1.4227 +*/
1.4228 +#define SQLITE_UTF8 1
1.4229 +#define SQLITE_UTF16LE 2
1.4230 +#define SQLITE_UTF16BE 3
1.4231 +#define SQLITE_UTF16 4 /* Use native byte order */
1.4232 +#define SQLITE_ANY 5 /* Deprecated */
1.4233 +#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
1.4234 +
1.4235 +/*
1.4236 +** CAPI3REF: Function Flags
1.4237 +**
1.4238 +** These constants may be ORed together with the
1.4239 +** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
1.4240 +** to [sqlite3_create_function()], [sqlite3_create_function16()], or
1.4241 +** [sqlite3_create_function_v2()].
1.4242 +*/
1.4243 +#define SQLITE_DETERMINISTIC 0x800
1.4244 +
1.4245 +/*
1.4246 +** CAPI3REF: Deprecated Functions
1.4247 +** DEPRECATED
1.4248 +**
1.4249 +** These functions are [deprecated]. In order to maintain
1.4250 +** backwards compatibility with older code, these functions continue
1.4251 +** to be supported. However, new applications should avoid
1.4252 +** the use of these functions. To help encourage people to avoid
1.4253 +** using these functions, we are not going to tell you what they do.
1.4254 +*/
1.4255 +#ifndef SQLITE_OMIT_DEPRECATED
1.4256 +SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
1.4257 +SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
1.4258 +SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
1.4259 +SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
1.4260 +SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
1.4261 +SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
1.4262 + void*,sqlite3_int64);
1.4263 +#endif
1.4264 +
1.4265 +/*
1.4266 +** CAPI3REF: Obtaining SQL Function Parameter Values
1.4267 +**
1.4268 +** The C-language implementation of SQL functions and aggregates uses
1.4269 +** this set of interface routines to access the parameter values on
1.4270 +** the function or aggregate.
1.4271 +**
1.4272 +** The xFunc (for scalar functions) or xStep (for aggregates) parameters
1.4273 +** to [sqlite3_create_function()] and [sqlite3_create_function16()]
1.4274 +** define callbacks that implement the SQL functions and aggregates.
1.4275 +** The 3rd parameter to these callbacks is an array of pointers to
1.4276 +** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
1.4277 +** each parameter to the SQL function. These routines are used to
1.4278 +** extract values from the [sqlite3_value] objects.
1.4279 +**
1.4280 +** These routines work only with [protected sqlite3_value] objects.
1.4281 +** Any attempt to use these routines on an [unprotected sqlite3_value]
1.4282 +** object results in undefined behavior.
1.4283 +**
1.4284 +** ^These routines work just like the corresponding [column access functions]
1.4285 +** except that these routines take a single [protected sqlite3_value] object
1.4286 +** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
1.4287 +**
1.4288 +** ^The sqlite3_value_text16() interface extracts a UTF-16 string
1.4289 +** in the native byte-order of the host machine. ^The
1.4290 +** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
1.4291 +** extract UTF-16 strings as big-endian and little-endian respectively.
1.4292 +**
1.4293 +** ^(The sqlite3_value_numeric_type() interface attempts to apply
1.4294 +** numeric affinity to the value. This means that an attempt is
1.4295 +** made to convert the value to an integer or floating point. If
1.4296 +** such a conversion is possible without loss of information (in other
1.4297 +** words, if the value is a string that looks like a number)
1.4298 +** then the conversion is performed. Otherwise no conversion occurs.
1.4299 +** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
1.4300 +**
1.4301 +** Please pay particular attention to the fact that the pointer returned
1.4302 +** from [sqlite3_value_blob()], [sqlite3_value_text()], or
1.4303 +** [sqlite3_value_text16()] can be invalidated by a subsequent call to
1.4304 +** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
1.4305 +** or [sqlite3_value_text16()].
1.4306 +**
1.4307 +** These routines must be called from the same thread as
1.4308 +** the SQL function that supplied the [sqlite3_value*] parameters.
1.4309 +*/
1.4310 +SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
1.4311 +SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
1.4312 +SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
1.4313 +SQLITE_API double sqlite3_value_double(sqlite3_value*);
1.4314 +SQLITE_API int sqlite3_value_int(sqlite3_value*);
1.4315 +SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
1.4316 +SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
1.4317 +SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
1.4318 +SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
1.4319 +SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
1.4320 +SQLITE_API int sqlite3_value_type(sqlite3_value*);
1.4321 +SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
1.4322 +
1.4323 +/*
1.4324 +** CAPI3REF: Obtain Aggregate Function Context
1.4325 +**
1.4326 +** Implementations of aggregate SQL functions use this
1.4327 +** routine to allocate memory for storing their state.
1.4328 +**
1.4329 +** ^The first time the sqlite3_aggregate_context(C,N) routine is called
1.4330 +** for a particular aggregate function, SQLite
1.4331 +** allocates N of memory, zeroes out that memory, and returns a pointer
1.4332 +** to the new memory. ^On second and subsequent calls to
1.4333 +** sqlite3_aggregate_context() for the same aggregate function instance,
1.4334 +** the same buffer is returned. Sqlite3_aggregate_context() is normally
1.4335 +** called once for each invocation of the xStep callback and then one
1.4336 +** last time when the xFinal callback is invoked. ^(When no rows match
1.4337 +** an aggregate query, the xStep() callback of the aggregate function
1.4338 +** implementation is never called and xFinal() is called exactly once.
1.4339 +** In those cases, sqlite3_aggregate_context() might be called for the
1.4340 +** first time from within xFinal().)^
1.4341 +**
1.4342 +** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
1.4343 +** when first called if N is less than or equal to zero or if a memory
1.4344 +** allocate error occurs.
1.4345 +**
1.4346 +** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
1.4347 +** determined by the N parameter on first successful call. Changing the
1.4348 +** value of N in subsequent call to sqlite3_aggregate_context() within
1.4349 +** the same aggregate function instance will not resize the memory
1.4350 +** allocation.)^ Within the xFinal callback, it is customary to set
1.4351 +** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
1.4352 +** pointless memory allocations occur.
1.4353 +**
1.4354 +** ^SQLite automatically frees the memory allocated by
1.4355 +** sqlite3_aggregate_context() when the aggregate query concludes.
1.4356 +**
1.4357 +** The first parameter must be a copy of the
1.4358 +** [sqlite3_context | SQL function context] that is the first parameter
1.4359 +** to the xStep or xFinal callback routine that implements the aggregate
1.4360 +** function.
1.4361 +**
1.4362 +** This routine must be called from the same thread in which
1.4363 +** the aggregate SQL function is running.
1.4364 +*/
1.4365 +SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
1.4366 +
1.4367 +/*
1.4368 +** CAPI3REF: User Data For Functions
1.4369 +**
1.4370 +** ^The sqlite3_user_data() interface returns a copy of
1.4371 +** the pointer that was the pUserData parameter (the 5th parameter)
1.4372 +** of the [sqlite3_create_function()]
1.4373 +** and [sqlite3_create_function16()] routines that originally
1.4374 +** registered the application defined function.
1.4375 +**
1.4376 +** This routine must be called from the same thread in which
1.4377 +** the application-defined function is running.
1.4378 +*/
1.4379 +SQLITE_API void *sqlite3_user_data(sqlite3_context*);
1.4380 +
1.4381 +/*
1.4382 +** CAPI3REF: Database Connection For Functions
1.4383 +**
1.4384 +** ^The sqlite3_context_db_handle() interface returns a copy of
1.4385 +** the pointer to the [database connection] (the 1st parameter)
1.4386 +** of the [sqlite3_create_function()]
1.4387 +** and [sqlite3_create_function16()] routines that originally
1.4388 +** registered the application defined function.
1.4389 +*/
1.4390 +SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
1.4391 +
1.4392 +/*
1.4393 +** CAPI3REF: Function Auxiliary Data
1.4394 +**
1.4395 +** These functions may be used by (non-aggregate) SQL functions to
1.4396 +** associate metadata with argument values. If the same value is passed to
1.4397 +** multiple invocations of the same SQL function during query execution, under
1.4398 +** some circumstances the associated metadata may be preserved. An example
1.4399 +** of where this might be useful is in a regular-expression matching
1.4400 +** function. The compiled version of the regular expression can be stored as
1.4401 +** metadata associated with the pattern string.
1.4402 +** Then as long as the pattern string remains the same,
1.4403 +** the compiled regular expression can be reused on multiple
1.4404 +** invocations of the same function.
1.4405 +**
1.4406 +** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
1.4407 +** associated by the sqlite3_set_auxdata() function with the Nth argument
1.4408 +** value to the application-defined function. ^If there is no metadata
1.4409 +** associated with the function argument, this sqlite3_get_auxdata() interface
1.4410 +** returns a NULL pointer.
1.4411 +**
1.4412 +** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
1.4413 +** argument of the application-defined function. ^Subsequent
1.4414 +** calls to sqlite3_get_auxdata(C,N) return P from the most recent
1.4415 +** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
1.4416 +** NULL if the metadata has been discarded.
1.4417 +** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
1.4418 +** SQLite will invoke the destructor function X with parameter P exactly
1.4419 +** once, when the metadata is discarded.
1.4420 +** SQLite is free to discard the metadata at any time, including: <ul>
1.4421 +** <li> when the corresponding function parameter changes, or
1.4422 +** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
1.4423 +** SQL statement, or
1.4424 +** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or
1.4425 +** <li> during the original sqlite3_set_auxdata() call when a memory
1.4426 +** allocation error occurs. </ul>)^
1.4427 +**
1.4428 +** Note the last bullet in particular. The destructor X in
1.4429 +** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
1.4430 +** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
1.4431 +** should be called near the end of the function implementation and the
1.4432 +** function implementation should not make any use of P after
1.4433 +** sqlite3_set_auxdata() has been called.
1.4434 +**
1.4435 +** ^(In practice, metadata is preserved between function calls for
1.4436 +** function parameters that are compile-time constants, including literal
1.4437 +** values and [parameters] and expressions composed from the same.)^
1.4438 +**
1.4439 +** These routines must be called from the same thread in which
1.4440 +** the SQL function is running.
1.4441 +*/
1.4442 +SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
1.4443 +SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
1.4444 +
1.4445 +
1.4446 +/*
1.4447 +** CAPI3REF: Constants Defining Special Destructor Behavior
1.4448 +**
1.4449 +** These are special values for the destructor that is passed in as the
1.4450 +** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
1.4451 +** argument is SQLITE_STATIC, it means that the content pointer is constant
1.4452 +** and will never change. It does not need to be destroyed. ^The
1.4453 +** SQLITE_TRANSIENT value means that the content will likely change in
1.4454 +** the near future and that SQLite should make its own private copy of
1.4455 +** the content before returning.
1.4456 +**
1.4457 +** The typedef is necessary to work around problems in certain
1.4458 +** C++ compilers.
1.4459 +*/
1.4460 +typedef void (*sqlite3_destructor_type)(void*);
1.4461 +#define SQLITE_STATIC ((sqlite3_destructor_type)0)
1.4462 +#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
1.4463 +
1.4464 +/*
1.4465 +** CAPI3REF: Setting The Result Of An SQL Function
1.4466 +**
1.4467 +** These routines are used by the xFunc or xFinal callbacks that
1.4468 +** implement SQL functions and aggregates. See
1.4469 +** [sqlite3_create_function()] and [sqlite3_create_function16()]
1.4470 +** for additional information.
1.4471 +**
1.4472 +** These functions work very much like the [parameter binding] family of
1.4473 +** functions used to bind values to host parameters in prepared statements.
1.4474 +** Refer to the [SQL parameter] documentation for additional information.
1.4475 +**
1.4476 +** ^The sqlite3_result_blob() interface sets the result from
1.4477 +** an application-defined function to be the BLOB whose content is pointed
1.4478 +** to by the second parameter and which is N bytes long where N is the
1.4479 +** third parameter.
1.4480 +**
1.4481 +** ^The sqlite3_result_zeroblob() interfaces set the result of
1.4482 +** the application-defined function to be a BLOB containing all zero
1.4483 +** bytes and N bytes in size, where N is the value of the 2nd parameter.
1.4484 +**
1.4485 +** ^The sqlite3_result_double() interface sets the result from
1.4486 +** an application-defined function to be a floating point value specified
1.4487 +** by its 2nd argument.
1.4488 +**
1.4489 +** ^The sqlite3_result_error() and sqlite3_result_error16() functions
1.4490 +** cause the implemented SQL function to throw an exception.
1.4491 +** ^SQLite uses the string pointed to by the
1.4492 +** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
1.4493 +** as the text of an error message. ^SQLite interprets the error
1.4494 +** message string from sqlite3_result_error() as UTF-8. ^SQLite
1.4495 +** interprets the string from sqlite3_result_error16() as UTF-16 in native
1.4496 +** byte order. ^If the third parameter to sqlite3_result_error()
1.4497 +** or sqlite3_result_error16() is negative then SQLite takes as the error
1.4498 +** message all text up through the first zero character.
1.4499 +** ^If the third parameter to sqlite3_result_error() or
1.4500 +** sqlite3_result_error16() is non-negative then SQLite takes that many
1.4501 +** bytes (not characters) from the 2nd parameter as the error message.
1.4502 +** ^The sqlite3_result_error() and sqlite3_result_error16()
1.4503 +** routines make a private copy of the error message text before
1.4504 +** they return. Hence, the calling function can deallocate or
1.4505 +** modify the text after they return without harm.
1.4506 +** ^The sqlite3_result_error_code() function changes the error code
1.4507 +** returned by SQLite as a result of an error in a function. ^By default,
1.4508 +** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
1.4509 +** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
1.4510 +**
1.4511 +** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
1.4512 +** error indicating that a string or BLOB is too long to represent.
1.4513 +**
1.4514 +** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
1.4515 +** error indicating that a memory allocation failed.
1.4516 +**
1.4517 +** ^The sqlite3_result_int() interface sets the return value
1.4518 +** of the application-defined function to be the 32-bit signed integer
1.4519 +** value given in the 2nd argument.
1.4520 +** ^The sqlite3_result_int64() interface sets the return value
1.4521 +** of the application-defined function to be the 64-bit signed integer
1.4522 +** value given in the 2nd argument.
1.4523 +**
1.4524 +** ^The sqlite3_result_null() interface sets the return value
1.4525 +** of the application-defined function to be NULL.
1.4526 +**
1.4527 +** ^The sqlite3_result_text(), sqlite3_result_text16(),
1.4528 +** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
1.4529 +** set the return value of the application-defined function to be
1.4530 +** a text string which is represented as UTF-8, UTF-16 native byte order,
1.4531 +** UTF-16 little endian, or UTF-16 big endian, respectively.
1.4532 +** ^SQLite takes the text result from the application from
1.4533 +** the 2nd parameter of the sqlite3_result_text* interfaces.
1.4534 +** ^If the 3rd parameter to the sqlite3_result_text* interfaces
1.4535 +** is negative, then SQLite takes result text from the 2nd parameter
1.4536 +** through the first zero character.
1.4537 +** ^If the 3rd parameter to the sqlite3_result_text* interfaces
1.4538 +** is non-negative, then as many bytes (not characters) of the text
1.4539 +** pointed to by the 2nd parameter are taken as the application-defined
1.4540 +** function result. If the 3rd parameter is non-negative, then it
1.4541 +** must be the byte offset into the string where the NUL terminator would
1.4542 +** appear if the string where NUL terminated. If any NUL characters occur
1.4543 +** in the string at a byte offset that is less than the value of the 3rd
1.4544 +** parameter, then the resulting string will contain embedded NULs and the
1.4545 +** result of expressions operating on strings with embedded NULs is undefined.
1.4546 +** ^If the 4th parameter to the sqlite3_result_text* interfaces
1.4547 +** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
1.4548 +** function as the destructor on the text or BLOB result when it has
1.4549 +** finished using that result.
1.4550 +** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
1.4551 +** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
1.4552 +** assumes that the text or BLOB result is in constant space and does not
1.4553 +** copy the content of the parameter nor call a destructor on the content
1.4554 +** when it has finished using that result.
1.4555 +** ^If the 4th parameter to the sqlite3_result_text* interfaces
1.4556 +** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
1.4557 +** then SQLite makes a copy of the result into space obtained from
1.4558 +** from [sqlite3_malloc()] before it returns.
1.4559 +**
1.4560 +** ^The sqlite3_result_value() interface sets the result of
1.4561 +** the application-defined function to be a copy the
1.4562 +** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
1.4563 +** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
1.4564 +** so that the [sqlite3_value] specified in the parameter may change or
1.4565 +** be deallocated after sqlite3_result_value() returns without harm.
1.4566 +** ^A [protected sqlite3_value] object may always be used where an
1.4567 +** [unprotected sqlite3_value] object is required, so either
1.4568 +** kind of [sqlite3_value] object can be used with this interface.
1.4569 +**
1.4570 +** If these routines are called from within the different thread
1.4571 +** than the one containing the application-defined function that received
1.4572 +** the [sqlite3_context] pointer, the results are undefined.
1.4573 +*/
1.4574 +SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
1.4575 +SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
1.4576 +SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
1.4577 +SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
1.4578 +SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
1.4579 +SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
1.4580 +SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
1.4581 +SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
1.4582 +SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
1.4583 +SQLITE_API void sqlite3_result_null(sqlite3_context*);
1.4584 +SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
1.4585 +SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
1.4586 +SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
1.4587 +SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
1.4588 +SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
1.4589 +SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
1.4590 +
1.4591 +/*
1.4592 +** CAPI3REF: Define New Collating Sequences
1.4593 +**
1.4594 +** ^These functions add, remove, or modify a [collation] associated
1.4595 +** with the [database connection] specified as the first argument.
1.4596 +**
1.4597 +** ^The name of the collation is a UTF-8 string
1.4598 +** for sqlite3_create_collation() and sqlite3_create_collation_v2()
1.4599 +** and a UTF-16 string in native byte order for sqlite3_create_collation16().
1.4600 +** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
1.4601 +** considered to be the same name.
1.4602 +**
1.4603 +** ^(The third argument (eTextRep) must be one of the constants:
1.4604 +** <ul>
1.4605 +** <li> [SQLITE_UTF8],
1.4606 +** <li> [SQLITE_UTF16LE],
1.4607 +** <li> [SQLITE_UTF16BE],
1.4608 +** <li> [SQLITE_UTF16], or
1.4609 +** <li> [SQLITE_UTF16_ALIGNED].
1.4610 +** </ul>)^
1.4611 +** ^The eTextRep argument determines the encoding of strings passed
1.4612 +** to the collating function callback, xCallback.
1.4613 +** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
1.4614 +** force strings to be UTF16 with native byte order.
1.4615 +** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
1.4616 +** on an even byte address.
1.4617 +**
1.4618 +** ^The fourth argument, pArg, is an application data pointer that is passed
1.4619 +** through as the first argument to the collating function callback.
1.4620 +**
1.4621 +** ^The fifth argument, xCallback, is a pointer to the collating function.
1.4622 +** ^Multiple collating functions can be registered using the same name but
1.4623 +** with different eTextRep parameters and SQLite will use whichever
1.4624 +** function requires the least amount of data transformation.
1.4625 +** ^If the xCallback argument is NULL then the collating function is
1.4626 +** deleted. ^When all collating functions having the same name are deleted,
1.4627 +** that collation is no longer usable.
1.4628 +**
1.4629 +** ^The collating function callback is invoked with a copy of the pArg
1.4630 +** application data pointer and with two strings in the encoding specified
1.4631 +** by the eTextRep argument. The collating function must return an
1.4632 +** integer that is negative, zero, or positive
1.4633 +** if the first string is less than, equal to, or greater than the second,
1.4634 +** respectively. A collating function must always return the same answer
1.4635 +** given the same inputs. If two or more collating functions are registered
1.4636 +** to the same collation name (using different eTextRep values) then all
1.4637 +** must give an equivalent answer when invoked with equivalent strings.
1.4638 +** The collating function must obey the following properties for all
1.4639 +** strings A, B, and C:
1.4640 +**
1.4641 +** <ol>
1.4642 +** <li> If A==B then B==A.
1.4643 +** <li> If A==B and B==C then A==C.
1.4644 +** <li> If A<B THEN B>A.
1.4645 +** <li> If A<B and B<C then A<C.
1.4646 +** </ol>
1.4647 +**
1.4648 +** If a collating function fails any of the above constraints and that
1.4649 +** collating function is registered and used, then the behavior of SQLite
1.4650 +** is undefined.
1.4651 +**
1.4652 +** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
1.4653 +** with the addition that the xDestroy callback is invoked on pArg when
1.4654 +** the collating function is deleted.
1.4655 +** ^Collating functions are deleted when they are overridden by later
1.4656 +** calls to the collation creation functions or when the
1.4657 +** [database connection] is closed using [sqlite3_close()].
1.4658 +**
1.4659 +** ^The xDestroy callback is <u>not</u> called if the
1.4660 +** sqlite3_create_collation_v2() function fails. Applications that invoke
1.4661 +** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
1.4662 +** check the return code and dispose of the application data pointer
1.4663 +** themselves rather than expecting SQLite to deal with it for them.
1.4664 +** This is different from every other SQLite interface. The inconsistency
1.4665 +** is unfortunate but cannot be changed without breaking backwards
1.4666 +** compatibility.
1.4667 +**
1.4668 +** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
1.4669 +*/
1.4670 +SQLITE_API int sqlite3_create_collation(
1.4671 + sqlite3*,
1.4672 + const char *zName,
1.4673 + int eTextRep,
1.4674 + void *pArg,
1.4675 + int(*xCompare)(void*,int,const void*,int,const void*)
1.4676 +);
1.4677 +SQLITE_API int sqlite3_create_collation_v2(
1.4678 + sqlite3*,
1.4679 + const char *zName,
1.4680 + int eTextRep,
1.4681 + void *pArg,
1.4682 + int(*xCompare)(void*,int,const void*,int,const void*),
1.4683 + void(*xDestroy)(void*)
1.4684 +);
1.4685 +SQLITE_API int sqlite3_create_collation16(
1.4686 + sqlite3*,
1.4687 + const void *zName,
1.4688 + int eTextRep,
1.4689 + void *pArg,
1.4690 + int(*xCompare)(void*,int,const void*,int,const void*)
1.4691 +);
1.4692 +
1.4693 +/*
1.4694 +** CAPI3REF: Collation Needed Callbacks
1.4695 +**
1.4696 +** ^To avoid having to register all collation sequences before a database
1.4697 +** can be used, a single callback function may be registered with the
1.4698 +** [database connection] to be invoked whenever an undefined collation
1.4699 +** sequence is required.
1.4700 +**
1.4701 +** ^If the function is registered using the sqlite3_collation_needed() API,
1.4702 +** then it is passed the names of undefined collation sequences as strings
1.4703 +** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
1.4704 +** the names are passed as UTF-16 in machine native byte order.
1.4705 +** ^A call to either function replaces the existing collation-needed callback.
1.4706 +**
1.4707 +** ^(When the callback is invoked, the first argument passed is a copy
1.4708 +** of the second argument to sqlite3_collation_needed() or
1.4709 +** sqlite3_collation_needed16(). The second argument is the database
1.4710 +** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
1.4711 +** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
1.4712 +** sequence function required. The fourth parameter is the name of the
1.4713 +** required collation sequence.)^
1.4714 +**
1.4715 +** The callback function should register the desired collation using
1.4716 +** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
1.4717 +** [sqlite3_create_collation_v2()].
1.4718 +*/
1.4719 +SQLITE_API int sqlite3_collation_needed(
1.4720 + sqlite3*,
1.4721 + void*,
1.4722 + void(*)(void*,sqlite3*,int eTextRep,const char*)
1.4723 +);
1.4724 +SQLITE_API int sqlite3_collation_needed16(
1.4725 + sqlite3*,
1.4726 + void*,
1.4727 + void(*)(void*,sqlite3*,int eTextRep,const void*)
1.4728 +);
1.4729 +
1.4730 +#ifdef SQLITE_HAS_CODEC
1.4731 +/*
1.4732 +** Specify the key for an encrypted database. This routine should be
1.4733 +** called right after sqlite3_open().
1.4734 +**
1.4735 +** The code to implement this API is not available in the public release
1.4736 +** of SQLite.
1.4737 +*/
1.4738 +SQLITE_API int sqlite3_key(
1.4739 + sqlite3 *db, /* Database to be rekeyed */
1.4740 + const void *pKey, int nKey /* The key */
1.4741 +);
1.4742 +SQLITE_API int sqlite3_key_v2(
1.4743 + sqlite3 *db, /* Database to be rekeyed */
1.4744 + const char *zDbName, /* Name of the database */
1.4745 + const void *pKey, int nKey /* The key */
1.4746 +);
1.4747 +
1.4748 +/*
1.4749 +** Change the key on an open database. If the current database is not
1.4750 +** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
1.4751 +** database is decrypted.
1.4752 +**
1.4753 +** The code to implement this API is not available in the public release
1.4754 +** of SQLite.
1.4755 +*/
1.4756 +SQLITE_API int sqlite3_rekey(
1.4757 + sqlite3 *db, /* Database to be rekeyed */
1.4758 + const void *pKey, int nKey /* The new key */
1.4759 +);
1.4760 +SQLITE_API int sqlite3_rekey_v2(
1.4761 + sqlite3 *db, /* Database to be rekeyed */
1.4762 + const char *zDbName, /* Name of the database */
1.4763 + const void *pKey, int nKey /* The new key */
1.4764 +);
1.4765 +
1.4766 +/*
1.4767 +** Specify the activation key for a SEE database. Unless
1.4768 +** activated, none of the SEE routines will work.
1.4769 +*/
1.4770 +SQLITE_API void sqlite3_activate_see(
1.4771 + const char *zPassPhrase /* Activation phrase */
1.4772 +);
1.4773 +#endif
1.4774 +
1.4775 +#ifdef SQLITE_ENABLE_CEROD
1.4776 +/*
1.4777 +** Specify the activation key for a CEROD database. Unless
1.4778 +** activated, none of the CEROD routines will work.
1.4779 +*/
1.4780 +SQLITE_API void sqlite3_activate_cerod(
1.4781 + const char *zPassPhrase /* Activation phrase */
1.4782 +);
1.4783 +#endif
1.4784 +
1.4785 +/*
1.4786 +** CAPI3REF: Suspend Execution For A Short Time
1.4787 +**
1.4788 +** The sqlite3_sleep() function causes the current thread to suspend execution
1.4789 +** for at least a number of milliseconds specified in its parameter.
1.4790 +**
1.4791 +** If the operating system does not support sleep requests with
1.4792 +** millisecond time resolution, then the time will be rounded up to
1.4793 +** the nearest second. The number of milliseconds of sleep actually
1.4794 +** requested from the operating system is returned.
1.4795 +**
1.4796 +** ^SQLite implements this interface by calling the xSleep()
1.4797 +** method of the default [sqlite3_vfs] object. If the xSleep() method
1.4798 +** of the default VFS is not implemented correctly, or not implemented at
1.4799 +** all, then the behavior of sqlite3_sleep() may deviate from the description
1.4800 +** in the previous paragraphs.
1.4801 +*/
1.4802 +SQLITE_API int sqlite3_sleep(int);
1.4803 +
1.4804 +/*
1.4805 +** CAPI3REF: Name Of The Folder Holding Temporary Files
1.4806 +**
1.4807 +** ^(If this global variable is made to point to a string which is
1.4808 +** the name of a folder (a.k.a. directory), then all temporary files
1.4809 +** created by SQLite when using a built-in [sqlite3_vfs | VFS]
1.4810 +** will be placed in that directory.)^ ^If this variable
1.4811 +** is a NULL pointer, then SQLite performs a search for an appropriate
1.4812 +** temporary file directory.
1.4813 +**
1.4814 +** Applications are strongly discouraged from using this global variable.
1.4815 +** It is required to set a temporary folder on Windows Runtime (WinRT).
1.4816 +** But for all other platforms, it is highly recommended that applications
1.4817 +** neither read nor write this variable. This global variable is a relic
1.4818 +** that exists for backwards compatibility of legacy applications and should
1.4819 +** be avoided in new projects.
1.4820 +**
1.4821 +** It is not safe to read or modify this variable in more than one
1.4822 +** thread at a time. It is not safe to read or modify this variable
1.4823 +** if a [database connection] is being used at the same time in a separate
1.4824 +** thread.
1.4825 +** It is intended that this variable be set once
1.4826 +** as part of process initialization and before any SQLite interface
1.4827 +** routines have been called and that this variable remain unchanged
1.4828 +** thereafter.
1.4829 +**
1.4830 +** ^The [temp_store_directory pragma] may modify this variable and cause
1.4831 +** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
1.4832 +** the [temp_store_directory pragma] always assumes that any string
1.4833 +** that this variable points to is held in memory obtained from
1.4834 +** [sqlite3_malloc] and the pragma may attempt to free that memory
1.4835 +** using [sqlite3_free].
1.4836 +** Hence, if this variable is modified directly, either it should be
1.4837 +** made NULL or made to point to memory obtained from [sqlite3_malloc]
1.4838 +** or else the use of the [temp_store_directory pragma] should be avoided.
1.4839 +** Except when requested by the [temp_store_directory pragma], SQLite
1.4840 +** does not free the memory that sqlite3_temp_directory points to. If
1.4841 +** the application wants that memory to be freed, it must do
1.4842 +** so itself, taking care to only do so after all [database connection]
1.4843 +** objects have been destroyed.
1.4844 +**
1.4845 +** <b>Note to Windows Runtime users:</b> The temporary directory must be set
1.4846 +** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
1.4847 +** features that require the use of temporary files may fail. Here is an
1.4848 +** example of how to do this using C++ with the Windows Runtime:
1.4849 +**
1.4850 +** <blockquote><pre>
1.4851 +** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
1.4852 +** TemporaryFolder->Path->Data();
1.4853 +** char zPathBuf[MAX_PATH + 1];
1.4854 +** memset(zPathBuf, 0, sizeof(zPathBuf));
1.4855 +** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
1.4856 +** NULL, NULL);
1.4857 +** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
1.4858 +** </pre></blockquote>
1.4859 +*/
1.4860 +SQLITE_API char *sqlite3_temp_directory;
1.4861 +
1.4862 +/*
1.4863 +** CAPI3REF: Name Of The Folder Holding Database Files
1.4864 +**
1.4865 +** ^(If this global variable is made to point to a string which is
1.4866 +** the name of a folder (a.k.a. directory), then all database files
1.4867 +** specified with a relative pathname and created or accessed by
1.4868 +** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
1.4869 +** to be relative to that directory.)^ ^If this variable is a NULL
1.4870 +** pointer, then SQLite assumes that all database files specified
1.4871 +** with a relative pathname are relative to the current directory
1.4872 +** for the process. Only the windows VFS makes use of this global
1.4873 +** variable; it is ignored by the unix VFS.
1.4874 +**
1.4875 +** Changing the value of this variable while a database connection is
1.4876 +** open can result in a corrupt database.
1.4877 +**
1.4878 +** It is not safe to read or modify this variable in more than one
1.4879 +** thread at a time. It is not safe to read or modify this variable
1.4880 +** if a [database connection] is being used at the same time in a separate
1.4881 +** thread.
1.4882 +** It is intended that this variable be set once
1.4883 +** as part of process initialization and before any SQLite interface
1.4884 +** routines have been called and that this variable remain unchanged
1.4885 +** thereafter.
1.4886 +**
1.4887 +** ^The [data_store_directory pragma] may modify this variable and cause
1.4888 +** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
1.4889 +** the [data_store_directory pragma] always assumes that any string
1.4890 +** that this variable points to is held in memory obtained from
1.4891 +** [sqlite3_malloc] and the pragma may attempt to free that memory
1.4892 +** using [sqlite3_free].
1.4893 +** Hence, if this variable is modified directly, either it should be
1.4894 +** made NULL or made to point to memory obtained from [sqlite3_malloc]
1.4895 +** or else the use of the [data_store_directory pragma] should be avoided.
1.4896 +*/
1.4897 +SQLITE_API char *sqlite3_data_directory;
1.4898 +
1.4899 +/*
1.4900 +** CAPI3REF: Test For Auto-Commit Mode
1.4901 +** KEYWORDS: {autocommit mode}
1.4902 +**
1.4903 +** ^The sqlite3_get_autocommit() interface returns non-zero or
1.4904 +** zero if the given database connection is or is not in autocommit mode,
1.4905 +** respectively. ^Autocommit mode is on by default.
1.4906 +** ^Autocommit mode is disabled by a [BEGIN] statement.
1.4907 +** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
1.4908 +**
1.4909 +** If certain kinds of errors occur on a statement within a multi-statement
1.4910 +** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
1.4911 +** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
1.4912 +** transaction might be rolled back automatically. The only way to
1.4913 +** find out whether SQLite automatically rolled back the transaction after
1.4914 +** an error is to use this function.
1.4915 +**
1.4916 +** If another thread changes the autocommit status of the database
1.4917 +** connection while this routine is running, then the return value
1.4918 +** is undefined.
1.4919 +*/
1.4920 +SQLITE_API int sqlite3_get_autocommit(sqlite3*);
1.4921 +
1.4922 +/*
1.4923 +** CAPI3REF: Find The Database Handle Of A Prepared Statement
1.4924 +**
1.4925 +** ^The sqlite3_db_handle interface returns the [database connection] handle
1.4926 +** to which a [prepared statement] belongs. ^The [database connection]
1.4927 +** returned by sqlite3_db_handle is the same [database connection]
1.4928 +** that was the first argument
1.4929 +** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
1.4930 +** create the statement in the first place.
1.4931 +*/
1.4932 +SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
1.4933 +
1.4934 +/*
1.4935 +** CAPI3REF: Return The Filename For A Database Connection
1.4936 +**
1.4937 +** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
1.4938 +** associated with database N of connection D. ^The main database file
1.4939 +** has the name "main". If there is no attached database N on the database
1.4940 +** connection D, or if database N is a temporary or in-memory database, then
1.4941 +** a NULL pointer is returned.
1.4942 +**
1.4943 +** ^The filename returned by this function is the output of the
1.4944 +** xFullPathname method of the [VFS]. ^In other words, the filename
1.4945 +** will be an absolute pathname, even if the filename used
1.4946 +** to open the database originally was a URI or relative pathname.
1.4947 +*/
1.4948 +SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
1.4949 +
1.4950 +/*
1.4951 +** CAPI3REF: Determine if a database is read-only
1.4952 +**
1.4953 +** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
1.4954 +** of connection D is read-only, 0 if it is read/write, or -1 if N is not
1.4955 +** the name of a database on connection D.
1.4956 +*/
1.4957 +SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
1.4958 +
1.4959 +/*
1.4960 +** CAPI3REF: Find the next prepared statement
1.4961 +**
1.4962 +** ^This interface returns a pointer to the next [prepared statement] after
1.4963 +** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
1.4964 +** then this interface returns a pointer to the first prepared statement
1.4965 +** associated with the database connection pDb. ^If no prepared statement
1.4966 +** satisfies the conditions of this routine, it returns NULL.
1.4967 +**
1.4968 +** The [database connection] pointer D in a call to
1.4969 +** [sqlite3_next_stmt(D,S)] must refer to an open database
1.4970 +** connection and in particular must not be a NULL pointer.
1.4971 +*/
1.4972 +SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
1.4973 +
1.4974 +/*
1.4975 +** CAPI3REF: Commit And Rollback Notification Callbacks
1.4976 +**
1.4977 +** ^The sqlite3_commit_hook() interface registers a callback
1.4978 +** function to be invoked whenever a transaction is [COMMIT | committed].
1.4979 +** ^Any callback set by a previous call to sqlite3_commit_hook()
1.4980 +** for the same database connection is overridden.
1.4981 +** ^The sqlite3_rollback_hook() interface registers a callback
1.4982 +** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
1.4983 +** ^Any callback set by a previous call to sqlite3_rollback_hook()
1.4984 +** for the same database connection is overridden.
1.4985 +** ^The pArg argument is passed through to the callback.
1.4986 +** ^If the callback on a commit hook function returns non-zero,
1.4987 +** then the commit is converted into a rollback.
1.4988 +**
1.4989 +** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
1.4990 +** return the P argument from the previous call of the same function
1.4991 +** on the same [database connection] D, or NULL for
1.4992 +** the first call for each function on D.
1.4993 +**
1.4994 +** The commit and rollback hook callbacks are not reentrant.
1.4995 +** The callback implementation must not do anything that will modify
1.4996 +** the database connection that invoked the callback. Any actions
1.4997 +** to modify the database connection must be deferred until after the
1.4998 +** completion of the [sqlite3_step()] call that triggered the commit
1.4999 +** or rollback hook in the first place.
1.5000 +** Note that running any other SQL statements, including SELECT statements,
1.5001 +** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
1.5002 +** the database connections for the meaning of "modify" in this paragraph.
1.5003 +**
1.5004 +** ^Registering a NULL function disables the callback.
1.5005 +**
1.5006 +** ^When the commit hook callback routine returns zero, the [COMMIT]
1.5007 +** operation is allowed to continue normally. ^If the commit hook
1.5008 +** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
1.5009 +** ^The rollback hook is invoked on a rollback that results from a commit
1.5010 +** hook returning non-zero, just as it would be with any other rollback.
1.5011 +**
1.5012 +** ^For the purposes of this API, a transaction is said to have been
1.5013 +** rolled back if an explicit "ROLLBACK" statement is executed, or
1.5014 +** an error or constraint causes an implicit rollback to occur.
1.5015 +** ^The rollback callback is not invoked if a transaction is
1.5016 +** automatically rolled back because the database connection is closed.
1.5017 +**
1.5018 +** See also the [sqlite3_update_hook()] interface.
1.5019 +*/
1.5020 +SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
1.5021 +SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
1.5022 +
1.5023 +/*
1.5024 +** CAPI3REF: Data Change Notification Callbacks
1.5025 +**
1.5026 +** ^The sqlite3_update_hook() interface registers a callback function
1.5027 +** with the [database connection] identified by the first argument
1.5028 +** to be invoked whenever a row is updated, inserted or deleted in
1.5029 +** a rowid table.
1.5030 +** ^Any callback set by a previous call to this function
1.5031 +** for the same database connection is overridden.
1.5032 +**
1.5033 +** ^The second argument is a pointer to the function to invoke when a
1.5034 +** row is updated, inserted or deleted in a rowid table.
1.5035 +** ^The first argument to the callback is a copy of the third argument
1.5036 +** to sqlite3_update_hook().
1.5037 +** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
1.5038 +** or [SQLITE_UPDATE], depending on the operation that caused the callback
1.5039 +** to be invoked.
1.5040 +** ^The third and fourth arguments to the callback contain pointers to the
1.5041 +** database and table name containing the affected row.
1.5042 +** ^The final callback parameter is the [rowid] of the row.
1.5043 +** ^In the case of an update, this is the [rowid] after the update takes place.
1.5044 +**
1.5045 +** ^(The update hook is not invoked when internal system tables are
1.5046 +** modified (i.e. sqlite_master and sqlite_sequence).)^
1.5047 +** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
1.5048 +**
1.5049 +** ^In the current implementation, the update hook
1.5050 +** is not invoked when duplication rows are deleted because of an
1.5051 +** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
1.5052 +** invoked when rows are deleted using the [truncate optimization].
1.5053 +** The exceptions defined in this paragraph might change in a future
1.5054 +** release of SQLite.
1.5055 +**
1.5056 +** The update hook implementation must not do anything that will modify
1.5057 +** the database connection that invoked the update hook. Any actions
1.5058 +** to modify the database connection must be deferred until after the
1.5059 +** completion of the [sqlite3_step()] call that triggered the update hook.
1.5060 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
1.5061 +** database connections for the meaning of "modify" in this paragraph.
1.5062 +**
1.5063 +** ^The sqlite3_update_hook(D,C,P) function
1.5064 +** returns the P argument from the previous call
1.5065 +** on the same [database connection] D, or NULL for
1.5066 +** the first call on D.
1.5067 +**
1.5068 +** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
1.5069 +** interfaces.
1.5070 +*/
1.5071 +SQLITE_API void *sqlite3_update_hook(
1.5072 + sqlite3*,
1.5073 + void(*)(void *,int ,char const *,char const *,sqlite3_int64),
1.5074 + void*
1.5075 +);
1.5076 +
1.5077 +/*
1.5078 +** CAPI3REF: Enable Or Disable Shared Pager Cache
1.5079 +**
1.5080 +** ^(This routine enables or disables the sharing of the database cache
1.5081 +** and schema data structures between [database connection | connections]
1.5082 +** to the same database. Sharing is enabled if the argument is true
1.5083 +** and disabled if the argument is false.)^
1.5084 +**
1.5085 +** ^Cache sharing is enabled and disabled for an entire process.
1.5086 +** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
1.5087 +** sharing was enabled or disabled for each thread separately.
1.5088 +**
1.5089 +** ^(The cache sharing mode set by this interface effects all subsequent
1.5090 +** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
1.5091 +** Existing database connections continue use the sharing mode
1.5092 +** that was in effect at the time they were opened.)^
1.5093 +**
1.5094 +** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
1.5095 +** successfully. An [error code] is returned otherwise.)^
1.5096 +**
1.5097 +** ^Shared cache is disabled by default. But this might change in
1.5098 +** future releases of SQLite. Applications that care about shared
1.5099 +** cache setting should set it explicitly.
1.5100 +**
1.5101 +** This interface is threadsafe on processors where writing a
1.5102 +** 32-bit integer is atomic.
1.5103 +**
1.5104 +** See Also: [SQLite Shared-Cache Mode]
1.5105 +*/
1.5106 +SQLITE_API int sqlite3_enable_shared_cache(int);
1.5107 +
1.5108 +/*
1.5109 +** CAPI3REF: Attempt To Free Heap Memory
1.5110 +**
1.5111 +** ^The sqlite3_release_memory() interface attempts to free N bytes
1.5112 +** of heap memory by deallocating non-essential memory allocations
1.5113 +** held by the database library. Memory used to cache database
1.5114 +** pages to improve performance is an example of non-essential memory.
1.5115 +** ^sqlite3_release_memory() returns the number of bytes actually freed,
1.5116 +** which might be more or less than the amount requested.
1.5117 +** ^The sqlite3_release_memory() routine is a no-op returning zero
1.5118 +** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
1.5119 +**
1.5120 +** See also: [sqlite3_db_release_memory()]
1.5121 +*/
1.5122 +SQLITE_API int sqlite3_release_memory(int);
1.5123 +
1.5124 +/*
1.5125 +** CAPI3REF: Free Memory Used By A Database Connection
1.5126 +**
1.5127 +** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
1.5128 +** memory as possible from database connection D. Unlike the
1.5129 +** [sqlite3_release_memory()] interface, this interface is in effect even
1.5130 +** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
1.5131 +** omitted.
1.5132 +**
1.5133 +** See also: [sqlite3_release_memory()]
1.5134 +*/
1.5135 +SQLITE_API int sqlite3_db_release_memory(sqlite3*);
1.5136 +
1.5137 +/*
1.5138 +** CAPI3REF: Impose A Limit On Heap Size
1.5139 +**
1.5140 +** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
1.5141 +** soft limit on the amount of heap memory that may be allocated by SQLite.
1.5142 +** ^SQLite strives to keep heap memory utilization below the soft heap
1.5143 +** limit by reducing the number of pages held in the page cache
1.5144 +** as heap memory usages approaches the limit.
1.5145 +** ^The soft heap limit is "soft" because even though SQLite strives to stay
1.5146 +** below the limit, it will exceed the limit rather than generate
1.5147 +** an [SQLITE_NOMEM] error. In other words, the soft heap limit
1.5148 +** is advisory only.
1.5149 +**
1.5150 +** ^The return value from sqlite3_soft_heap_limit64() is the size of
1.5151 +** the soft heap limit prior to the call, or negative in the case of an
1.5152 +** error. ^If the argument N is negative
1.5153 +** then no change is made to the soft heap limit. Hence, the current
1.5154 +** size of the soft heap limit can be determined by invoking
1.5155 +** sqlite3_soft_heap_limit64() with a negative argument.
1.5156 +**
1.5157 +** ^If the argument N is zero then the soft heap limit is disabled.
1.5158 +**
1.5159 +** ^(The soft heap limit is not enforced in the current implementation
1.5160 +** if one or more of following conditions are true:
1.5161 +**
1.5162 +** <ul>
1.5163 +** <li> The soft heap limit is set to zero.
1.5164 +** <li> Memory accounting is disabled using a combination of the
1.5165 +** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
1.5166 +** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
1.5167 +** <li> An alternative page cache implementation is specified using
1.5168 +** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
1.5169 +** <li> The page cache allocates from its own memory pool supplied
1.5170 +** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
1.5171 +** from the heap.
1.5172 +** </ul>)^
1.5173 +**
1.5174 +** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
1.5175 +** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
1.5176 +** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
1.5177 +** the soft heap limit is enforced on every memory allocation. Without
1.5178 +** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
1.5179 +** when memory is allocated by the page cache. Testing suggests that because
1.5180 +** the page cache is the predominate memory user in SQLite, most
1.5181 +** applications will achieve adequate soft heap limit enforcement without
1.5182 +** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
1.5183 +**
1.5184 +** The circumstances under which SQLite will enforce the soft heap limit may
1.5185 +** changes in future releases of SQLite.
1.5186 +*/
1.5187 +SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
1.5188 +
1.5189 +/*
1.5190 +** CAPI3REF: Deprecated Soft Heap Limit Interface
1.5191 +** DEPRECATED
1.5192 +**
1.5193 +** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
1.5194 +** interface. This routine is provided for historical compatibility
1.5195 +** only. All new applications should use the
1.5196 +** [sqlite3_soft_heap_limit64()] interface rather than this one.
1.5197 +*/
1.5198 +SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
1.5199 +
1.5200 +
1.5201 +/*
1.5202 +** CAPI3REF: Extract Metadata About A Column Of A Table
1.5203 +**
1.5204 +** ^This routine returns metadata about a specific column of a specific
1.5205 +** database table accessible using the [database connection] handle
1.5206 +** passed as the first function argument.
1.5207 +**
1.5208 +** ^The column is identified by the second, third and fourth parameters to
1.5209 +** this function. ^The second parameter is either the name of the database
1.5210 +** (i.e. "main", "temp", or an attached database) containing the specified
1.5211 +** table or NULL. ^If it is NULL, then all attached databases are searched
1.5212 +** for the table using the same algorithm used by the database engine to
1.5213 +** resolve unqualified table references.
1.5214 +**
1.5215 +** ^The third and fourth parameters to this function are the table and column
1.5216 +** name of the desired column, respectively. Neither of these parameters
1.5217 +** may be NULL.
1.5218 +**
1.5219 +** ^Metadata is returned by writing to the memory locations passed as the 5th
1.5220 +** and subsequent parameters to this function. ^Any of these arguments may be
1.5221 +** NULL, in which case the corresponding element of metadata is omitted.
1.5222 +**
1.5223 +** ^(<blockquote>
1.5224 +** <table border="1">
1.5225 +** <tr><th> Parameter <th> Output<br>Type <th> Description
1.5226 +**
1.5227 +** <tr><td> 5th <td> const char* <td> Data type
1.5228 +** <tr><td> 6th <td> const char* <td> Name of default collation sequence
1.5229 +** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
1.5230 +** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
1.5231 +** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
1.5232 +** </table>
1.5233 +** </blockquote>)^
1.5234 +**
1.5235 +** ^The memory pointed to by the character pointers returned for the
1.5236 +** declaration type and collation sequence is valid only until the next
1.5237 +** call to any SQLite API function.
1.5238 +**
1.5239 +** ^If the specified table is actually a view, an [error code] is returned.
1.5240 +**
1.5241 +** ^If the specified column is "rowid", "oid" or "_rowid_" and an
1.5242 +** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
1.5243 +** parameters are set for the explicitly declared column. ^(If there is no
1.5244 +** explicitly declared [INTEGER PRIMARY KEY] column, then the output
1.5245 +** parameters are set as follows:
1.5246 +**
1.5247 +** <pre>
1.5248 +** data type: "INTEGER"
1.5249 +** collation sequence: "BINARY"
1.5250 +** not null: 0
1.5251 +** primary key: 1
1.5252 +** auto increment: 0
1.5253 +** </pre>)^
1.5254 +**
1.5255 +** ^(This function may load one or more schemas from database files. If an
1.5256 +** error occurs during this process, or if the requested table or column
1.5257 +** cannot be found, an [error code] is returned and an error message left
1.5258 +** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
1.5259 +**
1.5260 +** ^This API is only available if the library was compiled with the
1.5261 +** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
1.5262 +*/
1.5263 +SQLITE_API int sqlite3_table_column_metadata(
1.5264 + sqlite3 *db, /* Connection handle */
1.5265 + const char *zDbName, /* Database name or NULL */
1.5266 + const char *zTableName, /* Table name */
1.5267 + const char *zColumnName, /* Column name */
1.5268 + char const **pzDataType, /* OUTPUT: Declared data type */
1.5269 + char const **pzCollSeq, /* OUTPUT: Collation sequence name */
1.5270 + int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
1.5271 + int *pPrimaryKey, /* OUTPUT: True if column part of PK */
1.5272 + int *pAutoinc /* OUTPUT: True if column is auto-increment */
1.5273 +);
1.5274 +
1.5275 +/*
1.5276 +** CAPI3REF: Load An Extension
1.5277 +**
1.5278 +** ^This interface loads an SQLite extension library from the named file.
1.5279 +**
1.5280 +** ^The sqlite3_load_extension() interface attempts to load an
1.5281 +** [SQLite extension] library contained in the file zFile. If
1.5282 +** the file cannot be loaded directly, attempts are made to load
1.5283 +** with various operating-system specific extensions added.
1.5284 +** So for example, if "samplelib" cannot be loaded, then names like
1.5285 +** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
1.5286 +** be tried also.
1.5287 +**
1.5288 +** ^The entry point is zProc.
1.5289 +** ^(zProc may be 0, in which case SQLite will try to come up with an
1.5290 +** entry point name on its own. It first tries "sqlite3_extension_init".
1.5291 +** If that does not work, it constructs a name "sqlite3_X_init" where the
1.5292 +** X is consists of the lower-case equivalent of all ASCII alphabetic
1.5293 +** characters in the filename from the last "/" to the first following
1.5294 +** "." and omitting any initial "lib".)^
1.5295 +** ^The sqlite3_load_extension() interface returns
1.5296 +** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
1.5297 +** ^If an error occurs and pzErrMsg is not 0, then the
1.5298 +** [sqlite3_load_extension()] interface shall attempt to
1.5299 +** fill *pzErrMsg with error message text stored in memory
1.5300 +** obtained from [sqlite3_malloc()]. The calling function
1.5301 +** should free this memory by calling [sqlite3_free()].
1.5302 +**
1.5303 +** ^Extension loading must be enabled using
1.5304 +** [sqlite3_enable_load_extension()] prior to calling this API,
1.5305 +** otherwise an error will be returned.
1.5306 +**
1.5307 +** See also the [load_extension() SQL function].
1.5308 +*/
1.5309 +SQLITE_API int sqlite3_load_extension(
1.5310 + sqlite3 *db, /* Load the extension into this database connection */
1.5311 + const char *zFile, /* Name of the shared library containing extension */
1.5312 + const char *zProc, /* Entry point. Derived from zFile if 0 */
1.5313 + char **pzErrMsg /* Put error message here if not 0 */
1.5314 +);
1.5315 +
1.5316 +/*
1.5317 +** CAPI3REF: Enable Or Disable Extension Loading
1.5318 +**
1.5319 +** ^So as not to open security holes in older applications that are
1.5320 +** unprepared to deal with [extension loading], and as a means of disabling
1.5321 +** [extension loading] while evaluating user-entered SQL, the following API
1.5322 +** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
1.5323 +**
1.5324 +** ^Extension loading is off by default.
1.5325 +** ^Call the sqlite3_enable_load_extension() routine with onoff==1
1.5326 +** to turn extension loading on and call it with onoff==0 to turn
1.5327 +** it back off again.
1.5328 +*/
1.5329 +SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
1.5330 +
1.5331 +/*
1.5332 +** CAPI3REF: Automatically Load Statically Linked Extensions
1.5333 +**
1.5334 +** ^This interface causes the xEntryPoint() function to be invoked for
1.5335 +** each new [database connection] that is created. The idea here is that
1.5336 +** xEntryPoint() is the entry point for a statically linked [SQLite extension]
1.5337 +** that is to be automatically loaded into all new database connections.
1.5338 +**
1.5339 +** ^(Even though the function prototype shows that xEntryPoint() takes
1.5340 +** no arguments and returns void, SQLite invokes xEntryPoint() with three
1.5341 +** arguments and expects and integer result as if the signature of the
1.5342 +** entry point where as follows:
1.5343 +**
1.5344 +** <blockquote><pre>
1.5345 +** int xEntryPoint(
1.5346 +** sqlite3 *db,
1.5347 +** const char **pzErrMsg,
1.5348 +** const struct sqlite3_api_routines *pThunk
1.5349 +** );
1.5350 +** </pre></blockquote>)^
1.5351 +**
1.5352 +** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
1.5353 +** point to an appropriate error message (obtained from [sqlite3_mprintf()])
1.5354 +** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
1.5355 +** is NULL before calling the xEntryPoint(). ^SQLite will invoke
1.5356 +** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
1.5357 +** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
1.5358 +** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
1.5359 +**
1.5360 +** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
1.5361 +** on the list of automatic extensions is a harmless no-op. ^No entry point
1.5362 +** will be called more than once for each database connection that is opened.
1.5363 +**
1.5364 +** See also: [sqlite3_reset_auto_extension()]
1.5365 +** and [sqlite3_cancel_auto_extension()]
1.5366 +*/
1.5367 +SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
1.5368 +
1.5369 +/*
1.5370 +** CAPI3REF: Cancel Automatic Extension Loading
1.5371 +**
1.5372 +** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
1.5373 +** initialization routine X that was registered using a prior call to
1.5374 +** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
1.5375 +** routine returns 1 if initialization routine X was successfully
1.5376 +** unregistered and it returns 0 if X was not on the list of initialization
1.5377 +** routines.
1.5378 +*/
1.5379 +SQLITE_API int sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
1.5380 +
1.5381 +/*
1.5382 +** CAPI3REF: Reset Automatic Extension Loading
1.5383 +**
1.5384 +** ^This interface disables all automatic extensions previously
1.5385 +** registered using [sqlite3_auto_extension()].
1.5386 +*/
1.5387 +SQLITE_API void sqlite3_reset_auto_extension(void);
1.5388 +
1.5389 +/*
1.5390 +** The interface to the virtual-table mechanism is currently considered
1.5391 +** to be experimental. The interface might change in incompatible ways.
1.5392 +** If this is a problem for you, do not use the interface at this time.
1.5393 +**
1.5394 +** When the virtual-table mechanism stabilizes, we will declare the
1.5395 +** interface fixed, support it indefinitely, and remove this comment.
1.5396 +*/
1.5397 +
1.5398 +/*
1.5399 +** Structures used by the virtual table interface
1.5400 +*/
1.5401 +typedef struct sqlite3_vtab sqlite3_vtab;
1.5402 +typedef struct sqlite3_index_info sqlite3_index_info;
1.5403 +typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
1.5404 +typedef struct sqlite3_module sqlite3_module;
1.5405 +
1.5406 +/*
1.5407 +** CAPI3REF: Virtual Table Object
1.5408 +** KEYWORDS: sqlite3_module {virtual table module}
1.5409 +**
1.5410 +** This structure, sometimes called a "virtual table module",
1.5411 +** defines the implementation of a [virtual tables].
1.5412 +** This structure consists mostly of methods for the module.
1.5413 +**
1.5414 +** ^A virtual table module is created by filling in a persistent
1.5415 +** instance of this structure and passing a pointer to that instance
1.5416 +** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
1.5417 +** ^The registration remains valid until it is replaced by a different
1.5418 +** module or until the [database connection] closes. The content
1.5419 +** of this structure must not change while it is registered with
1.5420 +** any database connection.
1.5421 +*/
1.5422 +struct sqlite3_module {
1.5423 + int iVersion;
1.5424 + int (*xCreate)(sqlite3*, void *pAux,
1.5425 + int argc, const char *const*argv,
1.5426 + sqlite3_vtab **ppVTab, char**);
1.5427 + int (*xConnect)(sqlite3*, void *pAux,
1.5428 + int argc, const char *const*argv,
1.5429 + sqlite3_vtab **ppVTab, char**);
1.5430 + int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
1.5431 + int (*xDisconnect)(sqlite3_vtab *pVTab);
1.5432 + int (*xDestroy)(sqlite3_vtab *pVTab);
1.5433 + int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
1.5434 + int (*xClose)(sqlite3_vtab_cursor*);
1.5435 + int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
1.5436 + int argc, sqlite3_value **argv);
1.5437 + int (*xNext)(sqlite3_vtab_cursor*);
1.5438 + int (*xEof)(sqlite3_vtab_cursor*);
1.5439 + int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
1.5440 + int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
1.5441 + int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
1.5442 + int (*xBegin)(sqlite3_vtab *pVTab);
1.5443 + int (*xSync)(sqlite3_vtab *pVTab);
1.5444 + int (*xCommit)(sqlite3_vtab *pVTab);
1.5445 + int (*xRollback)(sqlite3_vtab *pVTab);
1.5446 + int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
1.5447 + void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
1.5448 + void **ppArg);
1.5449 + int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
1.5450 + /* The methods above are in version 1 of the sqlite_module object. Those
1.5451 + ** below are for version 2 and greater. */
1.5452 + int (*xSavepoint)(sqlite3_vtab *pVTab, int);
1.5453 + int (*xRelease)(sqlite3_vtab *pVTab, int);
1.5454 + int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
1.5455 +};
1.5456 +
1.5457 +/*
1.5458 +** CAPI3REF: Virtual Table Indexing Information
1.5459 +** KEYWORDS: sqlite3_index_info
1.5460 +**
1.5461 +** The sqlite3_index_info structure and its substructures is used as part
1.5462 +** of the [virtual table] interface to
1.5463 +** pass information into and receive the reply from the [xBestIndex]
1.5464 +** method of a [virtual table module]. The fields under **Inputs** are the
1.5465 +** inputs to xBestIndex and are read-only. xBestIndex inserts its
1.5466 +** results into the **Outputs** fields.
1.5467 +**
1.5468 +** ^(The aConstraint[] array records WHERE clause constraints of the form:
1.5469 +**
1.5470 +** <blockquote>column OP expr</blockquote>
1.5471 +**
1.5472 +** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
1.5473 +** stored in aConstraint[].op using one of the
1.5474 +** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
1.5475 +** ^(The index of the column is stored in
1.5476 +** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
1.5477 +** expr on the right-hand side can be evaluated (and thus the constraint
1.5478 +** is usable) and false if it cannot.)^
1.5479 +**
1.5480 +** ^The optimizer automatically inverts terms of the form "expr OP column"
1.5481 +** and makes other simplifications to the WHERE clause in an attempt to
1.5482 +** get as many WHERE clause terms into the form shown above as possible.
1.5483 +** ^The aConstraint[] array only reports WHERE clause terms that are
1.5484 +** relevant to the particular virtual table being queried.
1.5485 +**
1.5486 +** ^Information about the ORDER BY clause is stored in aOrderBy[].
1.5487 +** ^Each term of aOrderBy records a column of the ORDER BY clause.
1.5488 +**
1.5489 +** The [xBestIndex] method must fill aConstraintUsage[] with information
1.5490 +** about what parameters to pass to xFilter. ^If argvIndex>0 then
1.5491 +** the right-hand side of the corresponding aConstraint[] is evaluated
1.5492 +** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
1.5493 +** is true, then the constraint is assumed to be fully handled by the
1.5494 +** virtual table and is not checked again by SQLite.)^
1.5495 +**
1.5496 +** ^The idxNum and idxPtr values are recorded and passed into the
1.5497 +** [xFilter] method.
1.5498 +** ^[sqlite3_free()] is used to free idxPtr if and only if
1.5499 +** needToFreeIdxPtr is true.
1.5500 +**
1.5501 +** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
1.5502 +** the correct order to satisfy the ORDER BY clause so that no separate
1.5503 +** sorting step is required.
1.5504 +**
1.5505 +** ^The estimatedCost value is an estimate of the cost of a particular
1.5506 +** strategy. A cost of N indicates that the cost of the strategy is similar
1.5507 +** to a linear scan of an SQLite table with N rows. A cost of log(N)
1.5508 +** indicates that the expense of the operation is similar to that of a
1.5509 +** binary search on a unique indexed field of an SQLite table with N rows.
1.5510 +**
1.5511 +** ^The estimatedRows value is an estimate of the number of rows that
1.5512 +** will be returned by the strategy.
1.5513 +**
1.5514 +** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
1.5515 +** structure for SQLite version 3.8.2. If a virtual table extension is
1.5516 +** used with an SQLite version earlier than 3.8.2, the results of attempting
1.5517 +** to read or write the estimatedRows field are undefined (but are likely
1.5518 +** to included crashing the application). The estimatedRows field should
1.5519 +** therefore only be used if [sqlite3_libversion_number()] returns a
1.5520 +** value greater than or equal to 3008002.
1.5521 +*/
1.5522 +struct sqlite3_index_info {
1.5523 + /* Inputs */
1.5524 + int nConstraint; /* Number of entries in aConstraint */
1.5525 + struct sqlite3_index_constraint {
1.5526 + int iColumn; /* Column on left-hand side of constraint */
1.5527 + unsigned char op; /* Constraint operator */
1.5528 + unsigned char usable; /* True if this constraint is usable */
1.5529 + int iTermOffset; /* Used internally - xBestIndex should ignore */
1.5530 + } *aConstraint; /* Table of WHERE clause constraints */
1.5531 + int nOrderBy; /* Number of terms in the ORDER BY clause */
1.5532 + struct sqlite3_index_orderby {
1.5533 + int iColumn; /* Column number */
1.5534 + unsigned char desc; /* True for DESC. False for ASC. */
1.5535 + } *aOrderBy; /* The ORDER BY clause */
1.5536 + /* Outputs */
1.5537 + struct sqlite3_index_constraint_usage {
1.5538 + int argvIndex; /* if >0, constraint is part of argv to xFilter */
1.5539 + unsigned char omit; /* Do not code a test for this constraint */
1.5540 + } *aConstraintUsage;
1.5541 + int idxNum; /* Number used to identify the index */
1.5542 + char *idxStr; /* String, possibly obtained from sqlite3_malloc */
1.5543 + int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
1.5544 + int orderByConsumed; /* True if output is already ordered */
1.5545 + double estimatedCost; /* Estimated cost of using this index */
1.5546 + /* Fields below are only available in SQLite 3.8.2 and later */
1.5547 + sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
1.5548 +};
1.5549 +
1.5550 +/*
1.5551 +** CAPI3REF: Virtual Table Constraint Operator Codes
1.5552 +**
1.5553 +** These macros defined the allowed values for the
1.5554 +** [sqlite3_index_info].aConstraint[].op field. Each value represents
1.5555 +** an operator that is part of a constraint term in the wHERE clause of
1.5556 +** a query that uses a [virtual table].
1.5557 +*/
1.5558 +#define SQLITE_INDEX_CONSTRAINT_EQ 2
1.5559 +#define SQLITE_INDEX_CONSTRAINT_GT 4
1.5560 +#define SQLITE_INDEX_CONSTRAINT_LE 8
1.5561 +#define SQLITE_INDEX_CONSTRAINT_LT 16
1.5562 +#define SQLITE_INDEX_CONSTRAINT_GE 32
1.5563 +#define SQLITE_INDEX_CONSTRAINT_MATCH 64
1.5564 +
1.5565 +/*
1.5566 +** CAPI3REF: Register A Virtual Table Implementation
1.5567 +**
1.5568 +** ^These routines are used to register a new [virtual table module] name.
1.5569 +** ^Module names must be registered before
1.5570 +** creating a new [virtual table] using the module and before using a
1.5571 +** preexisting [virtual table] for the module.
1.5572 +**
1.5573 +** ^The module name is registered on the [database connection] specified
1.5574 +** by the first parameter. ^The name of the module is given by the
1.5575 +** second parameter. ^The third parameter is a pointer to
1.5576 +** the implementation of the [virtual table module]. ^The fourth
1.5577 +** parameter is an arbitrary client data pointer that is passed through
1.5578 +** into the [xCreate] and [xConnect] methods of the virtual table module
1.5579 +** when a new virtual table is be being created or reinitialized.
1.5580 +**
1.5581 +** ^The sqlite3_create_module_v2() interface has a fifth parameter which
1.5582 +** is a pointer to a destructor for the pClientData. ^SQLite will
1.5583 +** invoke the destructor function (if it is not NULL) when SQLite
1.5584 +** no longer needs the pClientData pointer. ^The destructor will also
1.5585 +** be invoked if the call to sqlite3_create_module_v2() fails.
1.5586 +** ^The sqlite3_create_module()
1.5587 +** interface is equivalent to sqlite3_create_module_v2() with a NULL
1.5588 +** destructor.
1.5589 +*/
1.5590 +SQLITE_API int sqlite3_create_module(
1.5591 + sqlite3 *db, /* SQLite connection to register module with */
1.5592 + const char *zName, /* Name of the module */
1.5593 + const sqlite3_module *p, /* Methods for the module */
1.5594 + void *pClientData /* Client data for xCreate/xConnect */
1.5595 +);
1.5596 +SQLITE_API int sqlite3_create_module_v2(
1.5597 + sqlite3 *db, /* SQLite connection to register module with */
1.5598 + const char *zName, /* Name of the module */
1.5599 + const sqlite3_module *p, /* Methods for the module */
1.5600 + void *pClientData, /* Client data for xCreate/xConnect */
1.5601 + void(*xDestroy)(void*) /* Module destructor function */
1.5602 +);
1.5603 +
1.5604 +/*
1.5605 +** CAPI3REF: Virtual Table Instance Object
1.5606 +** KEYWORDS: sqlite3_vtab
1.5607 +**
1.5608 +** Every [virtual table module] implementation uses a subclass
1.5609 +** of this object to describe a particular instance
1.5610 +** of the [virtual table]. Each subclass will
1.5611 +** be tailored to the specific needs of the module implementation.
1.5612 +** The purpose of this superclass is to define certain fields that are
1.5613 +** common to all module implementations.
1.5614 +**
1.5615 +** ^Virtual tables methods can set an error message by assigning a
1.5616 +** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
1.5617 +** take care that any prior string is freed by a call to [sqlite3_free()]
1.5618 +** prior to assigning a new string to zErrMsg. ^After the error message
1.5619 +** is delivered up to the client application, the string will be automatically
1.5620 +** freed by sqlite3_free() and the zErrMsg field will be zeroed.
1.5621 +*/
1.5622 +struct sqlite3_vtab {
1.5623 + const sqlite3_module *pModule; /* The module for this virtual table */
1.5624 + int nRef; /* NO LONGER USED */
1.5625 + char *zErrMsg; /* Error message from sqlite3_mprintf() */
1.5626 + /* Virtual table implementations will typically add additional fields */
1.5627 +};
1.5628 +
1.5629 +/*
1.5630 +** CAPI3REF: Virtual Table Cursor Object
1.5631 +** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
1.5632 +**
1.5633 +** Every [virtual table module] implementation uses a subclass of the
1.5634 +** following structure to describe cursors that point into the
1.5635 +** [virtual table] and are used
1.5636 +** to loop through the virtual table. Cursors are created using the
1.5637 +** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
1.5638 +** by the [sqlite3_module.xClose | xClose] method. Cursors are used
1.5639 +** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
1.5640 +** of the module. Each module implementation will define
1.5641 +** the content of a cursor structure to suit its own needs.
1.5642 +**
1.5643 +** This superclass exists in order to define fields of the cursor that
1.5644 +** are common to all implementations.
1.5645 +*/
1.5646 +struct sqlite3_vtab_cursor {
1.5647 + sqlite3_vtab *pVtab; /* Virtual table of this cursor */
1.5648 + /* Virtual table implementations will typically add additional fields */
1.5649 +};
1.5650 +
1.5651 +/*
1.5652 +** CAPI3REF: Declare The Schema Of A Virtual Table
1.5653 +**
1.5654 +** ^The [xCreate] and [xConnect] methods of a
1.5655 +** [virtual table module] call this interface
1.5656 +** to declare the format (the names and datatypes of the columns) of
1.5657 +** the virtual tables they implement.
1.5658 +*/
1.5659 +SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
1.5660 +
1.5661 +/*
1.5662 +** CAPI3REF: Overload A Function For A Virtual Table
1.5663 +**
1.5664 +** ^(Virtual tables can provide alternative implementations of functions
1.5665 +** using the [xFindFunction] method of the [virtual table module].
1.5666 +** But global versions of those functions
1.5667 +** must exist in order to be overloaded.)^
1.5668 +**
1.5669 +** ^(This API makes sure a global version of a function with a particular
1.5670 +** name and number of parameters exists. If no such function exists
1.5671 +** before this API is called, a new function is created.)^ ^The implementation
1.5672 +** of the new function always causes an exception to be thrown. So
1.5673 +** the new function is not good for anything by itself. Its only
1.5674 +** purpose is to be a placeholder function that can be overloaded
1.5675 +** by a [virtual table].
1.5676 +*/
1.5677 +SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
1.5678 +
1.5679 +/*
1.5680 +** The interface to the virtual-table mechanism defined above (back up
1.5681 +** to a comment remarkably similar to this one) is currently considered
1.5682 +** to be experimental. The interface might change in incompatible ways.
1.5683 +** If this is a problem for you, do not use the interface at this time.
1.5684 +**
1.5685 +** When the virtual-table mechanism stabilizes, we will declare the
1.5686 +** interface fixed, support it indefinitely, and remove this comment.
1.5687 +*/
1.5688 +
1.5689 +/*
1.5690 +** CAPI3REF: A Handle To An Open BLOB
1.5691 +** KEYWORDS: {BLOB handle} {BLOB handles}
1.5692 +**
1.5693 +** An instance of this object represents an open BLOB on which
1.5694 +** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
1.5695 +** ^Objects of this type are created by [sqlite3_blob_open()]
1.5696 +** and destroyed by [sqlite3_blob_close()].
1.5697 +** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
1.5698 +** can be used to read or write small subsections of the BLOB.
1.5699 +** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
1.5700 +*/
1.5701 +typedef struct sqlite3_blob sqlite3_blob;
1.5702 +
1.5703 +/*
1.5704 +** CAPI3REF: Open A BLOB For Incremental I/O
1.5705 +**
1.5706 +** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
1.5707 +** in row iRow, column zColumn, table zTable in database zDb;
1.5708 +** in other words, the same BLOB that would be selected by:
1.5709 +**
1.5710 +** <pre>
1.5711 +** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
1.5712 +** </pre>)^
1.5713 +**
1.5714 +** ^If the flags parameter is non-zero, then the BLOB is opened for read
1.5715 +** and write access. ^If it is zero, the BLOB is opened for read access.
1.5716 +** ^It is not possible to open a column that is part of an index or primary
1.5717 +** key for writing. ^If [foreign key constraints] are enabled, it is
1.5718 +** not possible to open a column that is part of a [child key] for writing.
1.5719 +**
1.5720 +** ^Note that the database name is not the filename that contains
1.5721 +** the database but rather the symbolic name of the database that
1.5722 +** appears after the AS keyword when the database is connected using [ATTACH].
1.5723 +** ^For the main database file, the database name is "main".
1.5724 +** ^For TEMP tables, the database name is "temp".
1.5725 +**
1.5726 +** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
1.5727 +** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
1.5728 +** to be a null pointer.)^
1.5729 +** ^This function sets the [database connection] error code and message
1.5730 +** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
1.5731 +** functions. ^Note that the *ppBlob variable is always initialized in a
1.5732 +** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
1.5733 +** regardless of the success or failure of this routine.
1.5734 +**
1.5735 +** ^(If the row that a BLOB handle points to is modified by an
1.5736 +** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
1.5737 +** then the BLOB handle is marked as "expired".
1.5738 +** This is true if any column of the row is changed, even a column
1.5739 +** other than the one the BLOB handle is open on.)^
1.5740 +** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
1.5741 +** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
1.5742 +** ^(Changes written into a BLOB prior to the BLOB expiring are not
1.5743 +** rolled back by the expiration of the BLOB. Such changes will eventually
1.5744 +** commit if the transaction continues to completion.)^
1.5745 +**
1.5746 +** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
1.5747 +** the opened blob. ^The size of a blob may not be changed by this
1.5748 +** interface. Use the [UPDATE] SQL command to change the size of a
1.5749 +** blob.
1.5750 +**
1.5751 +** ^The [sqlite3_blob_open()] interface will fail for a [WITHOUT ROWID]
1.5752 +** table. Incremental BLOB I/O is not possible on [WITHOUT ROWID] tables.
1.5753 +**
1.5754 +** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
1.5755 +** and the built-in [zeroblob] SQL function can be used, if desired,
1.5756 +** to create an empty, zero-filled blob in which to read or write using
1.5757 +** this interface.
1.5758 +**
1.5759 +** To avoid a resource leak, every open [BLOB handle] should eventually
1.5760 +** be released by a call to [sqlite3_blob_close()].
1.5761 +*/
1.5762 +SQLITE_API int sqlite3_blob_open(
1.5763 + sqlite3*,
1.5764 + const char *zDb,
1.5765 + const char *zTable,
1.5766 + const char *zColumn,
1.5767 + sqlite3_int64 iRow,
1.5768 + int flags,
1.5769 + sqlite3_blob **ppBlob
1.5770 +);
1.5771 +
1.5772 +/*
1.5773 +** CAPI3REF: Move a BLOB Handle to a New Row
1.5774 +**
1.5775 +** ^This function is used to move an existing blob handle so that it points
1.5776 +** to a different row of the same database table. ^The new row is identified
1.5777 +** by the rowid value passed as the second argument. Only the row can be
1.5778 +** changed. ^The database, table and column on which the blob handle is open
1.5779 +** remain the same. Moving an existing blob handle to a new row can be
1.5780 +** faster than closing the existing handle and opening a new one.
1.5781 +**
1.5782 +** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
1.5783 +** it must exist and there must be either a blob or text value stored in
1.5784 +** the nominated column.)^ ^If the new row is not present in the table, or if
1.5785 +** it does not contain a blob or text value, or if another error occurs, an
1.5786 +** SQLite error code is returned and the blob handle is considered aborted.
1.5787 +** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
1.5788 +** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
1.5789 +** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
1.5790 +** always returns zero.
1.5791 +**
1.5792 +** ^This function sets the database handle error code and message.
1.5793 +*/
1.5794 +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
1.5795 +
1.5796 +/*
1.5797 +** CAPI3REF: Close A BLOB Handle
1.5798 +**
1.5799 +** ^Closes an open [BLOB handle].
1.5800 +**
1.5801 +** ^Closing a BLOB shall cause the current transaction to commit
1.5802 +** if there are no other BLOBs, no pending prepared statements, and the
1.5803 +** database connection is in [autocommit mode].
1.5804 +** ^If any writes were made to the BLOB, they might be held in cache
1.5805 +** until the close operation if they will fit.
1.5806 +**
1.5807 +** ^(Closing the BLOB often forces the changes
1.5808 +** out to disk and so if any I/O errors occur, they will likely occur
1.5809 +** at the time when the BLOB is closed. Any errors that occur during
1.5810 +** closing are reported as a non-zero return value.)^
1.5811 +**
1.5812 +** ^(The BLOB is closed unconditionally. Even if this routine returns
1.5813 +** an error code, the BLOB is still closed.)^
1.5814 +**
1.5815 +** ^Calling this routine with a null pointer (such as would be returned
1.5816 +** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
1.5817 +*/
1.5818 +SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
1.5819 +
1.5820 +/*
1.5821 +** CAPI3REF: Return The Size Of An Open BLOB
1.5822 +**
1.5823 +** ^Returns the size in bytes of the BLOB accessible via the
1.5824 +** successfully opened [BLOB handle] in its only argument. ^The
1.5825 +** incremental blob I/O routines can only read or overwriting existing
1.5826 +** blob content; they cannot change the size of a blob.
1.5827 +**
1.5828 +** This routine only works on a [BLOB handle] which has been created
1.5829 +** by a prior successful call to [sqlite3_blob_open()] and which has not
1.5830 +** been closed by [sqlite3_blob_close()]. Passing any other pointer in
1.5831 +** to this routine results in undefined and probably undesirable behavior.
1.5832 +*/
1.5833 +SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
1.5834 +
1.5835 +/*
1.5836 +** CAPI3REF: Read Data From A BLOB Incrementally
1.5837 +**
1.5838 +** ^(This function is used to read data from an open [BLOB handle] into a
1.5839 +** caller-supplied buffer. N bytes of data are copied into buffer Z
1.5840 +** from the open BLOB, starting at offset iOffset.)^
1.5841 +**
1.5842 +** ^If offset iOffset is less than N bytes from the end of the BLOB,
1.5843 +** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
1.5844 +** less than zero, [SQLITE_ERROR] is returned and no data is read.
1.5845 +** ^The size of the blob (and hence the maximum value of N+iOffset)
1.5846 +** can be determined using the [sqlite3_blob_bytes()] interface.
1.5847 +**
1.5848 +** ^An attempt to read from an expired [BLOB handle] fails with an
1.5849 +** error code of [SQLITE_ABORT].
1.5850 +**
1.5851 +** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
1.5852 +** Otherwise, an [error code] or an [extended error code] is returned.)^
1.5853 +**
1.5854 +** This routine only works on a [BLOB handle] which has been created
1.5855 +** by a prior successful call to [sqlite3_blob_open()] and which has not
1.5856 +** been closed by [sqlite3_blob_close()]. Passing any other pointer in
1.5857 +** to this routine results in undefined and probably undesirable behavior.
1.5858 +**
1.5859 +** See also: [sqlite3_blob_write()].
1.5860 +*/
1.5861 +SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
1.5862 +
1.5863 +/*
1.5864 +** CAPI3REF: Write Data Into A BLOB Incrementally
1.5865 +**
1.5866 +** ^This function is used to write data into an open [BLOB handle] from a
1.5867 +** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
1.5868 +** into the open BLOB, starting at offset iOffset.
1.5869 +**
1.5870 +** ^If the [BLOB handle] passed as the first argument was not opened for
1.5871 +** writing (the flags parameter to [sqlite3_blob_open()] was zero),
1.5872 +** this function returns [SQLITE_READONLY].
1.5873 +**
1.5874 +** ^This function may only modify the contents of the BLOB; it is
1.5875 +** not possible to increase the size of a BLOB using this API.
1.5876 +** ^If offset iOffset is less than N bytes from the end of the BLOB,
1.5877 +** [SQLITE_ERROR] is returned and no data is written. ^If N is
1.5878 +** less than zero [SQLITE_ERROR] is returned and no data is written.
1.5879 +** The size of the BLOB (and hence the maximum value of N+iOffset)
1.5880 +** can be determined using the [sqlite3_blob_bytes()] interface.
1.5881 +**
1.5882 +** ^An attempt to write to an expired [BLOB handle] fails with an
1.5883 +** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
1.5884 +** before the [BLOB handle] expired are not rolled back by the
1.5885 +** expiration of the handle, though of course those changes might
1.5886 +** have been overwritten by the statement that expired the BLOB handle
1.5887 +** or by other independent statements.
1.5888 +**
1.5889 +** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
1.5890 +** Otherwise, an [error code] or an [extended error code] is returned.)^
1.5891 +**
1.5892 +** This routine only works on a [BLOB handle] which has been created
1.5893 +** by a prior successful call to [sqlite3_blob_open()] and which has not
1.5894 +** been closed by [sqlite3_blob_close()]. Passing any other pointer in
1.5895 +** to this routine results in undefined and probably undesirable behavior.
1.5896 +**
1.5897 +** See also: [sqlite3_blob_read()].
1.5898 +*/
1.5899 +SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
1.5900 +
1.5901 +/*
1.5902 +** CAPI3REF: Virtual File System Objects
1.5903 +**
1.5904 +** A virtual filesystem (VFS) is an [sqlite3_vfs] object
1.5905 +** that SQLite uses to interact
1.5906 +** with the underlying operating system. Most SQLite builds come with a
1.5907 +** single default VFS that is appropriate for the host computer.
1.5908 +** New VFSes can be registered and existing VFSes can be unregistered.
1.5909 +** The following interfaces are provided.
1.5910 +**
1.5911 +** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
1.5912 +** ^Names are case sensitive.
1.5913 +** ^Names are zero-terminated UTF-8 strings.
1.5914 +** ^If there is no match, a NULL pointer is returned.
1.5915 +** ^If zVfsName is NULL then the default VFS is returned.
1.5916 +**
1.5917 +** ^New VFSes are registered with sqlite3_vfs_register().
1.5918 +** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
1.5919 +** ^The same VFS can be registered multiple times without injury.
1.5920 +** ^To make an existing VFS into the default VFS, register it again
1.5921 +** with the makeDflt flag set. If two different VFSes with the
1.5922 +** same name are registered, the behavior is undefined. If a
1.5923 +** VFS is registered with a name that is NULL or an empty string,
1.5924 +** then the behavior is undefined.
1.5925 +**
1.5926 +** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
1.5927 +** ^(If the default VFS is unregistered, another VFS is chosen as
1.5928 +** the default. The choice for the new VFS is arbitrary.)^
1.5929 +*/
1.5930 +SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
1.5931 +SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
1.5932 +SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
1.5933 +
1.5934 +/*
1.5935 +** CAPI3REF: Mutexes
1.5936 +**
1.5937 +** The SQLite core uses these routines for thread
1.5938 +** synchronization. Though they are intended for internal
1.5939 +** use by SQLite, code that links against SQLite is
1.5940 +** permitted to use any of these routines.
1.5941 +**
1.5942 +** The SQLite source code contains multiple implementations
1.5943 +** of these mutex routines. An appropriate implementation
1.5944 +** is selected automatically at compile-time. ^(The following
1.5945 +** implementations are available in the SQLite core:
1.5946 +**
1.5947 +** <ul>
1.5948 +** <li> SQLITE_MUTEX_PTHREADS
1.5949 +** <li> SQLITE_MUTEX_W32
1.5950 +** <li> SQLITE_MUTEX_NOOP
1.5951 +** </ul>)^
1.5952 +**
1.5953 +** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
1.5954 +** that does no real locking and is appropriate for use in
1.5955 +** a single-threaded application. ^The SQLITE_MUTEX_PTHREADS and
1.5956 +** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
1.5957 +** and Windows.
1.5958 +**
1.5959 +** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
1.5960 +** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
1.5961 +** implementation is included with the library. In this case the
1.5962 +** application must supply a custom mutex implementation using the
1.5963 +** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
1.5964 +** before calling sqlite3_initialize() or any other public sqlite3_
1.5965 +** function that calls sqlite3_initialize().)^
1.5966 +**
1.5967 +** ^The sqlite3_mutex_alloc() routine allocates a new
1.5968 +** mutex and returns a pointer to it. ^If it returns NULL
1.5969 +** that means that a mutex could not be allocated. ^SQLite
1.5970 +** will unwind its stack and return an error. ^(The argument
1.5971 +** to sqlite3_mutex_alloc() is one of these integer constants:
1.5972 +**
1.5973 +** <ul>
1.5974 +** <li> SQLITE_MUTEX_FAST
1.5975 +** <li> SQLITE_MUTEX_RECURSIVE
1.5976 +** <li> SQLITE_MUTEX_STATIC_MASTER
1.5977 +** <li> SQLITE_MUTEX_STATIC_MEM
1.5978 +** <li> SQLITE_MUTEX_STATIC_OPEN
1.5979 +** <li> SQLITE_MUTEX_STATIC_PRNG
1.5980 +** <li> SQLITE_MUTEX_STATIC_LRU
1.5981 +** <li> SQLITE_MUTEX_STATIC_PMEM
1.5982 +** <li> SQLITE_MUTEX_STATIC_APP1
1.5983 +** <li> SQLITE_MUTEX_STATIC_APP2
1.5984 +** </ul>)^
1.5985 +**
1.5986 +** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
1.5987 +** cause sqlite3_mutex_alloc() to create
1.5988 +** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
1.5989 +** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
1.5990 +** The mutex implementation does not need to make a distinction
1.5991 +** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
1.5992 +** not want to. ^SQLite will only request a recursive mutex in
1.5993 +** cases where it really needs one. ^If a faster non-recursive mutex
1.5994 +** implementation is available on the host platform, the mutex subsystem
1.5995 +** might return such a mutex in response to SQLITE_MUTEX_FAST.
1.5996 +**
1.5997 +** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
1.5998 +** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
1.5999 +** a pointer to a static preexisting mutex. ^Six static mutexes are
1.6000 +** used by the current version of SQLite. Future versions of SQLite
1.6001 +** may add additional static mutexes. Static mutexes are for internal
1.6002 +** use by SQLite only. Applications that use SQLite mutexes should
1.6003 +** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
1.6004 +** SQLITE_MUTEX_RECURSIVE.
1.6005 +**
1.6006 +** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
1.6007 +** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
1.6008 +** returns a different mutex on every call. ^But for the static
1.6009 +** mutex types, the same mutex is returned on every call that has
1.6010 +** the same type number.
1.6011 +**
1.6012 +** ^The sqlite3_mutex_free() routine deallocates a previously
1.6013 +** allocated dynamic mutex. ^SQLite is careful to deallocate every
1.6014 +** dynamic mutex that it allocates. The dynamic mutexes must not be in
1.6015 +** use when they are deallocated. Attempting to deallocate a static
1.6016 +** mutex results in undefined behavior. ^SQLite never deallocates
1.6017 +** a static mutex.
1.6018 +**
1.6019 +** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
1.6020 +** to enter a mutex. ^If another thread is already within the mutex,
1.6021 +** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
1.6022 +** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
1.6023 +** upon successful entry. ^(Mutexes created using
1.6024 +** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
1.6025 +** In such cases the,
1.6026 +** mutex must be exited an equal number of times before another thread
1.6027 +** can enter.)^ ^(If the same thread tries to enter any other
1.6028 +** kind of mutex more than once, the behavior is undefined.
1.6029 +** SQLite will never exhibit
1.6030 +** such behavior in its own use of mutexes.)^
1.6031 +**
1.6032 +** ^(Some systems (for example, Windows 95) do not support the operation
1.6033 +** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
1.6034 +** will always return SQLITE_BUSY. The SQLite core only ever uses
1.6035 +** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
1.6036 +**
1.6037 +** ^The sqlite3_mutex_leave() routine exits a mutex that was
1.6038 +** previously entered by the same thread. ^(The behavior
1.6039 +** is undefined if the mutex is not currently entered by the
1.6040 +** calling thread or is not currently allocated. SQLite will
1.6041 +** never do either.)^
1.6042 +**
1.6043 +** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
1.6044 +** sqlite3_mutex_leave() is a NULL pointer, then all three routines
1.6045 +** behave as no-ops.
1.6046 +**
1.6047 +** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
1.6048 +*/
1.6049 +SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
1.6050 +SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
1.6051 +SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
1.6052 +SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
1.6053 +SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
1.6054 +
1.6055 +/*
1.6056 +** CAPI3REF: Mutex Methods Object
1.6057 +**
1.6058 +** An instance of this structure defines the low-level routines
1.6059 +** used to allocate and use mutexes.
1.6060 +**
1.6061 +** Usually, the default mutex implementations provided by SQLite are
1.6062 +** sufficient, however the user has the option of substituting a custom
1.6063 +** implementation for specialized deployments or systems for which SQLite
1.6064 +** does not provide a suitable implementation. In this case, the user
1.6065 +** creates and populates an instance of this structure to pass
1.6066 +** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
1.6067 +** Additionally, an instance of this structure can be used as an
1.6068 +** output variable when querying the system for the current mutex
1.6069 +** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
1.6070 +**
1.6071 +** ^The xMutexInit method defined by this structure is invoked as
1.6072 +** part of system initialization by the sqlite3_initialize() function.
1.6073 +** ^The xMutexInit routine is called by SQLite exactly once for each
1.6074 +** effective call to [sqlite3_initialize()].
1.6075 +**
1.6076 +** ^The xMutexEnd method defined by this structure is invoked as
1.6077 +** part of system shutdown by the sqlite3_shutdown() function. The
1.6078 +** implementation of this method is expected to release all outstanding
1.6079 +** resources obtained by the mutex methods implementation, especially
1.6080 +** those obtained by the xMutexInit method. ^The xMutexEnd()
1.6081 +** interface is invoked exactly once for each call to [sqlite3_shutdown()].
1.6082 +**
1.6083 +** ^(The remaining seven methods defined by this structure (xMutexAlloc,
1.6084 +** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
1.6085 +** xMutexNotheld) implement the following interfaces (respectively):
1.6086 +**
1.6087 +** <ul>
1.6088 +** <li> [sqlite3_mutex_alloc()] </li>
1.6089 +** <li> [sqlite3_mutex_free()] </li>
1.6090 +** <li> [sqlite3_mutex_enter()] </li>
1.6091 +** <li> [sqlite3_mutex_try()] </li>
1.6092 +** <li> [sqlite3_mutex_leave()] </li>
1.6093 +** <li> [sqlite3_mutex_held()] </li>
1.6094 +** <li> [sqlite3_mutex_notheld()] </li>
1.6095 +** </ul>)^
1.6096 +**
1.6097 +** The only difference is that the public sqlite3_XXX functions enumerated
1.6098 +** above silently ignore any invocations that pass a NULL pointer instead
1.6099 +** of a valid mutex handle. The implementations of the methods defined
1.6100 +** by this structure are not required to handle this case, the results
1.6101 +** of passing a NULL pointer instead of a valid mutex handle are undefined
1.6102 +** (i.e. it is acceptable to provide an implementation that segfaults if
1.6103 +** it is passed a NULL pointer).
1.6104 +**
1.6105 +** The xMutexInit() method must be threadsafe. ^It must be harmless to
1.6106 +** invoke xMutexInit() multiple times within the same process and without
1.6107 +** intervening calls to xMutexEnd(). Second and subsequent calls to
1.6108 +** xMutexInit() must be no-ops.
1.6109 +**
1.6110 +** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
1.6111 +** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
1.6112 +** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
1.6113 +** memory allocation for a fast or recursive mutex.
1.6114 +**
1.6115 +** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
1.6116 +** called, but only if the prior call to xMutexInit returned SQLITE_OK.
1.6117 +** If xMutexInit fails in any way, it is expected to clean up after itself
1.6118 +** prior to returning.
1.6119 +*/
1.6120 +typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
1.6121 +struct sqlite3_mutex_methods {
1.6122 + int (*xMutexInit)(void);
1.6123 + int (*xMutexEnd)(void);
1.6124 + sqlite3_mutex *(*xMutexAlloc)(int);
1.6125 + void (*xMutexFree)(sqlite3_mutex *);
1.6126 + void (*xMutexEnter)(sqlite3_mutex *);
1.6127 + int (*xMutexTry)(sqlite3_mutex *);
1.6128 + void (*xMutexLeave)(sqlite3_mutex *);
1.6129 + int (*xMutexHeld)(sqlite3_mutex *);
1.6130 + int (*xMutexNotheld)(sqlite3_mutex *);
1.6131 +};
1.6132 +
1.6133 +/*
1.6134 +** CAPI3REF: Mutex Verification Routines
1.6135 +**
1.6136 +** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
1.6137 +** are intended for use inside assert() statements. ^The SQLite core
1.6138 +** never uses these routines except inside an assert() and applications
1.6139 +** are advised to follow the lead of the core. ^The SQLite core only
1.6140 +** provides implementations for these routines when it is compiled
1.6141 +** with the SQLITE_DEBUG flag. ^External mutex implementations
1.6142 +** are only required to provide these routines if SQLITE_DEBUG is
1.6143 +** defined and if NDEBUG is not defined.
1.6144 +**
1.6145 +** ^These routines should return true if the mutex in their argument
1.6146 +** is held or not held, respectively, by the calling thread.
1.6147 +**
1.6148 +** ^The implementation is not required to provide versions of these
1.6149 +** routines that actually work. If the implementation does not provide working
1.6150 +** versions of these routines, it should at least provide stubs that always
1.6151 +** return true so that one does not get spurious assertion failures.
1.6152 +**
1.6153 +** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
1.6154 +** the routine should return 1. This seems counter-intuitive since
1.6155 +** clearly the mutex cannot be held if it does not exist. But
1.6156 +** the reason the mutex does not exist is because the build is not
1.6157 +** using mutexes. And we do not want the assert() containing the
1.6158 +** call to sqlite3_mutex_held() to fail, so a non-zero return is
1.6159 +** the appropriate thing to do. ^The sqlite3_mutex_notheld()
1.6160 +** interface should also return 1 when given a NULL pointer.
1.6161 +*/
1.6162 +#ifndef NDEBUG
1.6163 +SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
1.6164 +SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
1.6165 +#endif
1.6166 +
1.6167 +/*
1.6168 +** CAPI3REF: Mutex Types
1.6169 +**
1.6170 +** The [sqlite3_mutex_alloc()] interface takes a single argument
1.6171 +** which is one of these integer constants.
1.6172 +**
1.6173 +** The set of static mutexes may change from one SQLite release to the
1.6174 +** next. Applications that override the built-in mutex logic must be
1.6175 +** prepared to accommodate additional static mutexes.
1.6176 +*/
1.6177 +#define SQLITE_MUTEX_FAST 0
1.6178 +#define SQLITE_MUTEX_RECURSIVE 1
1.6179 +#define SQLITE_MUTEX_STATIC_MASTER 2
1.6180 +#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
1.6181 +#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
1.6182 +#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
1.6183 +#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
1.6184 +#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
1.6185 +#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
1.6186 +#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
1.6187 +#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */
1.6188 +#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */
1.6189 +#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */
1.6190 +
1.6191 +/*
1.6192 +** CAPI3REF: Retrieve the mutex for a database connection
1.6193 +**
1.6194 +** ^This interface returns a pointer the [sqlite3_mutex] object that
1.6195 +** serializes access to the [database connection] given in the argument
1.6196 +** when the [threading mode] is Serialized.
1.6197 +** ^If the [threading mode] is Single-thread or Multi-thread then this
1.6198 +** routine returns a NULL pointer.
1.6199 +*/
1.6200 +SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
1.6201 +
1.6202 +/*
1.6203 +** CAPI3REF: Low-Level Control Of Database Files
1.6204 +**
1.6205 +** ^The [sqlite3_file_control()] interface makes a direct call to the
1.6206 +** xFileControl method for the [sqlite3_io_methods] object associated
1.6207 +** with a particular database identified by the second argument. ^The
1.6208 +** name of the database is "main" for the main database or "temp" for the
1.6209 +** TEMP database, or the name that appears after the AS keyword for
1.6210 +** databases that are added using the [ATTACH] SQL command.
1.6211 +** ^A NULL pointer can be used in place of "main" to refer to the
1.6212 +** main database file.
1.6213 +** ^The third and fourth parameters to this routine
1.6214 +** are passed directly through to the second and third parameters of
1.6215 +** the xFileControl method. ^The return value of the xFileControl
1.6216 +** method becomes the return value of this routine.
1.6217 +**
1.6218 +** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
1.6219 +** a pointer to the underlying [sqlite3_file] object to be written into
1.6220 +** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER
1.6221 +** case is a short-circuit path which does not actually invoke the
1.6222 +** underlying sqlite3_io_methods.xFileControl method.
1.6223 +**
1.6224 +** ^If the second parameter (zDbName) does not match the name of any
1.6225 +** open database file, then SQLITE_ERROR is returned. ^This error
1.6226 +** code is not remembered and will not be recalled by [sqlite3_errcode()]
1.6227 +** or [sqlite3_errmsg()]. The underlying xFileControl method might
1.6228 +** also return SQLITE_ERROR. There is no way to distinguish between
1.6229 +** an incorrect zDbName and an SQLITE_ERROR return from the underlying
1.6230 +** xFileControl method.
1.6231 +**
1.6232 +** See also: [SQLITE_FCNTL_LOCKSTATE]
1.6233 +*/
1.6234 +SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
1.6235 +
1.6236 +/*
1.6237 +** CAPI3REF: Testing Interface
1.6238 +**
1.6239 +** ^The sqlite3_test_control() interface is used to read out internal
1.6240 +** state of SQLite and to inject faults into SQLite for testing
1.6241 +** purposes. ^The first parameter is an operation code that determines
1.6242 +** the number, meaning, and operation of all subsequent parameters.
1.6243 +**
1.6244 +** This interface is not for use by applications. It exists solely
1.6245 +** for verifying the correct operation of the SQLite library. Depending
1.6246 +** on how the SQLite library is compiled, this interface might not exist.
1.6247 +**
1.6248 +** The details of the operation codes, their meanings, the parameters
1.6249 +** they take, and what they do are all subject to change without notice.
1.6250 +** Unlike most of the SQLite API, this function is not guaranteed to
1.6251 +** operate consistently from one release to the next.
1.6252 +*/
1.6253 +SQLITE_API int sqlite3_test_control(int op, ...);
1.6254 +
1.6255 +/*
1.6256 +** CAPI3REF: Testing Interface Operation Codes
1.6257 +**
1.6258 +** These constants are the valid operation code parameters used
1.6259 +** as the first argument to [sqlite3_test_control()].
1.6260 +**
1.6261 +** These parameters and their meanings are subject to change
1.6262 +** without notice. These values are for testing purposes only.
1.6263 +** Applications should not use any of these parameters or the
1.6264 +** [sqlite3_test_control()] interface.
1.6265 +*/
1.6266 +#define SQLITE_TESTCTRL_FIRST 5
1.6267 +#define SQLITE_TESTCTRL_PRNG_SAVE 5
1.6268 +#define SQLITE_TESTCTRL_PRNG_RESTORE 6
1.6269 +#define SQLITE_TESTCTRL_PRNG_RESET 7
1.6270 +#define SQLITE_TESTCTRL_BITVEC_TEST 8
1.6271 +#define SQLITE_TESTCTRL_FAULT_INSTALL 9
1.6272 +#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
1.6273 +#define SQLITE_TESTCTRL_PENDING_BYTE 11
1.6274 +#define SQLITE_TESTCTRL_ASSERT 12
1.6275 +#define SQLITE_TESTCTRL_ALWAYS 13
1.6276 +#define SQLITE_TESTCTRL_RESERVE 14
1.6277 +#define SQLITE_TESTCTRL_OPTIMIZATIONS 15
1.6278 +#define SQLITE_TESTCTRL_ISKEYWORD 16
1.6279 +#define SQLITE_TESTCTRL_SCRATCHMALLOC 17
1.6280 +#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
1.6281 +#define SQLITE_TESTCTRL_EXPLAIN_STMT 19
1.6282 +#define SQLITE_TESTCTRL_NEVER_CORRUPT 20
1.6283 +#define SQLITE_TESTCTRL_VDBE_COVERAGE 21
1.6284 +#define SQLITE_TESTCTRL_BYTEORDER 22
1.6285 +#define SQLITE_TESTCTRL_ISINIT 23
1.6286 +#define SQLITE_TESTCTRL_LAST 23
1.6287 +
1.6288 +/*
1.6289 +** CAPI3REF: SQLite Runtime Status
1.6290 +**
1.6291 +** ^This interface is used to retrieve runtime status information
1.6292 +** about the performance of SQLite, and optionally to reset various
1.6293 +** highwater marks. ^The first argument is an integer code for
1.6294 +** the specific parameter to measure. ^(Recognized integer codes
1.6295 +** are of the form [status parameters | SQLITE_STATUS_...].)^
1.6296 +** ^The current value of the parameter is returned into *pCurrent.
1.6297 +** ^The highest recorded value is returned in *pHighwater. ^If the
1.6298 +** resetFlag is true, then the highest record value is reset after
1.6299 +** *pHighwater is written. ^(Some parameters do not record the highest
1.6300 +** value. For those parameters
1.6301 +** nothing is written into *pHighwater and the resetFlag is ignored.)^
1.6302 +** ^(Other parameters record only the highwater mark and not the current
1.6303 +** value. For these latter parameters nothing is written into *pCurrent.)^
1.6304 +**
1.6305 +** ^The sqlite3_status() routine returns SQLITE_OK on success and a
1.6306 +** non-zero [error code] on failure.
1.6307 +**
1.6308 +** This routine is threadsafe but is not atomic. This routine can be
1.6309 +** called while other threads are running the same or different SQLite
1.6310 +** interfaces. However the values returned in *pCurrent and
1.6311 +** *pHighwater reflect the status of SQLite at different points in time
1.6312 +** and it is possible that another thread might change the parameter
1.6313 +** in between the times when *pCurrent and *pHighwater are written.
1.6314 +**
1.6315 +** See also: [sqlite3_db_status()]
1.6316 +*/
1.6317 +SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
1.6318 +
1.6319 +
1.6320 +/*
1.6321 +** CAPI3REF: Status Parameters
1.6322 +** KEYWORDS: {status parameters}
1.6323 +**
1.6324 +** These integer constants designate various run-time status parameters
1.6325 +** that can be returned by [sqlite3_status()].
1.6326 +**
1.6327 +** <dl>
1.6328 +** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
1.6329 +** <dd>This parameter is the current amount of memory checked out
1.6330 +** using [sqlite3_malloc()], either directly or indirectly. The
1.6331 +** figure includes calls made to [sqlite3_malloc()] by the application
1.6332 +** and internal memory usage by the SQLite library. Scratch memory
1.6333 +** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
1.6334 +** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
1.6335 +** this parameter. The amount returned is the sum of the allocation
1.6336 +** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
1.6337 +**
1.6338 +** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
1.6339 +** <dd>This parameter records the largest memory allocation request
1.6340 +** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
1.6341 +** internal equivalents). Only the value returned in the
1.6342 +** *pHighwater parameter to [sqlite3_status()] is of interest.
1.6343 +** The value written into the *pCurrent parameter is undefined.</dd>)^
1.6344 +**
1.6345 +** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
1.6346 +** <dd>This parameter records the number of separate memory allocations
1.6347 +** currently checked out.</dd>)^
1.6348 +**
1.6349 +** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
1.6350 +** <dd>This parameter returns the number of pages used out of the
1.6351 +** [pagecache memory allocator] that was configured using
1.6352 +** [SQLITE_CONFIG_PAGECACHE]. The
1.6353 +** value returned is in pages, not in bytes.</dd>)^
1.6354 +**
1.6355 +** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
1.6356 +** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
1.6357 +** <dd>This parameter returns the number of bytes of page cache
1.6358 +** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
1.6359 +** buffer and where forced to overflow to [sqlite3_malloc()]. The
1.6360 +** returned value includes allocations that overflowed because they
1.6361 +** where too large (they were larger than the "sz" parameter to
1.6362 +** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
1.6363 +** no space was left in the page cache.</dd>)^
1.6364 +**
1.6365 +** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
1.6366 +** <dd>This parameter records the largest memory allocation request
1.6367 +** handed to [pagecache memory allocator]. Only the value returned in the
1.6368 +** *pHighwater parameter to [sqlite3_status()] is of interest.
1.6369 +** The value written into the *pCurrent parameter is undefined.</dd>)^
1.6370 +**
1.6371 +** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
1.6372 +** <dd>This parameter returns the number of allocations used out of the
1.6373 +** [scratch memory allocator] configured using
1.6374 +** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
1.6375 +** in bytes. Since a single thread may only have one scratch allocation
1.6376 +** outstanding at time, this parameter also reports the number of threads
1.6377 +** using scratch memory at the same time.</dd>)^
1.6378 +**
1.6379 +** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
1.6380 +** <dd>This parameter returns the number of bytes of scratch memory
1.6381 +** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
1.6382 +** buffer and where forced to overflow to [sqlite3_malloc()]. The values
1.6383 +** returned include overflows because the requested allocation was too
1.6384 +** larger (that is, because the requested allocation was larger than the
1.6385 +** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
1.6386 +** slots were available.
1.6387 +** </dd>)^
1.6388 +**
1.6389 +** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
1.6390 +** <dd>This parameter records the largest memory allocation request
1.6391 +** handed to [scratch memory allocator]. Only the value returned in the
1.6392 +** *pHighwater parameter to [sqlite3_status()] is of interest.
1.6393 +** The value written into the *pCurrent parameter is undefined.</dd>)^
1.6394 +**
1.6395 +** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
1.6396 +** <dd>This parameter records the deepest parser stack. It is only
1.6397 +** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
1.6398 +** </dl>
1.6399 +**
1.6400 +** New status parameters may be added from time to time.
1.6401 +*/
1.6402 +#define SQLITE_STATUS_MEMORY_USED 0
1.6403 +#define SQLITE_STATUS_PAGECACHE_USED 1
1.6404 +#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
1.6405 +#define SQLITE_STATUS_SCRATCH_USED 3
1.6406 +#define SQLITE_STATUS_SCRATCH_OVERFLOW 4
1.6407 +#define SQLITE_STATUS_MALLOC_SIZE 5
1.6408 +#define SQLITE_STATUS_PARSER_STACK 6
1.6409 +#define SQLITE_STATUS_PAGECACHE_SIZE 7
1.6410 +#define SQLITE_STATUS_SCRATCH_SIZE 8
1.6411 +#define SQLITE_STATUS_MALLOC_COUNT 9
1.6412 +
1.6413 +/*
1.6414 +** CAPI3REF: Database Connection Status
1.6415 +**
1.6416 +** ^This interface is used to retrieve runtime status information
1.6417 +** about a single [database connection]. ^The first argument is the
1.6418 +** database connection object to be interrogated. ^The second argument
1.6419 +** is an integer constant, taken from the set of
1.6420 +** [SQLITE_DBSTATUS options], that
1.6421 +** determines the parameter to interrogate. The set of
1.6422 +** [SQLITE_DBSTATUS options] is likely
1.6423 +** to grow in future releases of SQLite.
1.6424 +**
1.6425 +** ^The current value of the requested parameter is written into *pCur
1.6426 +** and the highest instantaneous value is written into *pHiwtr. ^If
1.6427 +** the resetFlg is true, then the highest instantaneous value is
1.6428 +** reset back down to the current value.
1.6429 +**
1.6430 +** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
1.6431 +** non-zero [error code] on failure.
1.6432 +**
1.6433 +** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
1.6434 +*/
1.6435 +SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
1.6436 +
1.6437 +/*
1.6438 +** CAPI3REF: Status Parameters for database connections
1.6439 +** KEYWORDS: {SQLITE_DBSTATUS options}
1.6440 +**
1.6441 +** These constants are the available integer "verbs" that can be passed as
1.6442 +** the second argument to the [sqlite3_db_status()] interface.
1.6443 +**
1.6444 +** New verbs may be added in future releases of SQLite. Existing verbs
1.6445 +** might be discontinued. Applications should check the return code from
1.6446 +** [sqlite3_db_status()] to make sure that the call worked.
1.6447 +** The [sqlite3_db_status()] interface will return a non-zero error code
1.6448 +** if a discontinued or unsupported verb is invoked.
1.6449 +**
1.6450 +** <dl>
1.6451 +** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
1.6452 +** <dd>This parameter returns the number of lookaside memory slots currently
1.6453 +** checked out.</dd>)^
1.6454 +**
1.6455 +** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
1.6456 +** <dd>This parameter returns the number malloc attempts that were
1.6457 +** satisfied using lookaside memory. Only the high-water value is meaningful;
1.6458 +** the current value is always zero.)^
1.6459 +**
1.6460 +** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
1.6461 +** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
1.6462 +** <dd>This parameter returns the number malloc attempts that might have
1.6463 +** been satisfied using lookaside memory but failed due to the amount of
1.6464 +** memory requested being larger than the lookaside slot size.
1.6465 +** Only the high-water value is meaningful;
1.6466 +** the current value is always zero.)^
1.6467 +**
1.6468 +** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
1.6469 +** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
1.6470 +** <dd>This parameter returns the number malloc attempts that might have
1.6471 +** been satisfied using lookaside memory but failed due to all lookaside
1.6472 +** memory already being in use.
1.6473 +** Only the high-water value is meaningful;
1.6474 +** the current value is always zero.)^
1.6475 +**
1.6476 +** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
1.6477 +** <dd>This parameter returns the approximate number of of bytes of heap
1.6478 +** memory used by all pager caches associated with the database connection.)^
1.6479 +** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
1.6480 +**
1.6481 +** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
1.6482 +** <dd>This parameter returns the approximate number of of bytes of heap
1.6483 +** memory used to store the schema for all databases associated
1.6484 +** with the connection - main, temp, and any [ATTACH]-ed databases.)^
1.6485 +** ^The full amount of memory used by the schemas is reported, even if the
1.6486 +** schema memory is shared with other database connections due to
1.6487 +** [shared cache mode] being enabled.
1.6488 +** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
1.6489 +**
1.6490 +** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
1.6491 +** <dd>This parameter returns the approximate number of of bytes of heap
1.6492 +** and lookaside memory used by all prepared statements associated with
1.6493 +** the database connection.)^
1.6494 +** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
1.6495 +** </dd>
1.6496 +**
1.6497 +** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
1.6498 +** <dd>This parameter returns the number of pager cache hits that have
1.6499 +** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
1.6500 +** is always 0.
1.6501 +** </dd>
1.6502 +**
1.6503 +** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
1.6504 +** <dd>This parameter returns the number of pager cache misses that have
1.6505 +** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
1.6506 +** is always 0.
1.6507 +** </dd>
1.6508 +**
1.6509 +** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
1.6510 +** <dd>This parameter returns the number of dirty cache entries that have
1.6511 +** been written to disk. Specifically, the number of pages written to the
1.6512 +** wal file in wal mode databases, or the number of pages written to the
1.6513 +** database file in rollback mode databases. Any pages written as part of
1.6514 +** transaction rollback or database recovery operations are not included.
1.6515 +** If an IO or other error occurs while writing a page to disk, the effect
1.6516 +** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
1.6517 +** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
1.6518 +** </dd>
1.6519 +**
1.6520 +** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
1.6521 +** <dd>This parameter returns zero for the current value if and only if
1.6522 +** all foreign key constraints (deferred or immediate) have been
1.6523 +** resolved.)^ ^The highwater mark is always 0.
1.6524 +** </dd>
1.6525 +** </dl>
1.6526 +*/
1.6527 +#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
1.6528 +#define SQLITE_DBSTATUS_CACHE_USED 1
1.6529 +#define SQLITE_DBSTATUS_SCHEMA_USED 2
1.6530 +#define SQLITE_DBSTATUS_STMT_USED 3
1.6531 +#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
1.6532 +#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
1.6533 +#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
1.6534 +#define SQLITE_DBSTATUS_CACHE_HIT 7
1.6535 +#define SQLITE_DBSTATUS_CACHE_MISS 8
1.6536 +#define SQLITE_DBSTATUS_CACHE_WRITE 9
1.6537 +#define SQLITE_DBSTATUS_DEFERRED_FKS 10
1.6538 +#define SQLITE_DBSTATUS_MAX 10 /* Largest defined DBSTATUS */
1.6539 +
1.6540 +
1.6541 +/*
1.6542 +** CAPI3REF: Prepared Statement Status
1.6543 +**
1.6544 +** ^(Each prepared statement maintains various
1.6545 +** [SQLITE_STMTSTATUS counters] that measure the number
1.6546 +** of times it has performed specific operations.)^ These counters can
1.6547 +** be used to monitor the performance characteristics of the prepared
1.6548 +** statements. For example, if the number of table steps greatly exceeds
1.6549 +** the number of table searches or result rows, that would tend to indicate
1.6550 +** that the prepared statement is using a full table scan rather than
1.6551 +** an index.
1.6552 +**
1.6553 +** ^(This interface is used to retrieve and reset counter values from
1.6554 +** a [prepared statement]. The first argument is the prepared statement
1.6555 +** object to be interrogated. The second argument
1.6556 +** is an integer code for a specific [SQLITE_STMTSTATUS counter]
1.6557 +** to be interrogated.)^
1.6558 +** ^The current value of the requested counter is returned.
1.6559 +** ^If the resetFlg is true, then the counter is reset to zero after this
1.6560 +** interface call returns.
1.6561 +**
1.6562 +** See also: [sqlite3_status()] and [sqlite3_db_status()].
1.6563 +*/
1.6564 +SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
1.6565 +
1.6566 +/*
1.6567 +** CAPI3REF: Status Parameters for prepared statements
1.6568 +** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
1.6569 +**
1.6570 +** These preprocessor macros define integer codes that name counter
1.6571 +** values associated with the [sqlite3_stmt_status()] interface.
1.6572 +** The meanings of the various counters are as follows:
1.6573 +**
1.6574 +** <dl>
1.6575 +** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
1.6576 +** <dd>^This is the number of times that SQLite has stepped forward in
1.6577 +** a table as part of a full table scan. Large numbers for this counter
1.6578 +** may indicate opportunities for performance improvement through
1.6579 +** careful use of indices.</dd>
1.6580 +**
1.6581 +** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
1.6582 +** <dd>^This is the number of sort operations that have occurred.
1.6583 +** A non-zero value in this counter may indicate an opportunity to
1.6584 +** improvement performance through careful use of indices.</dd>
1.6585 +**
1.6586 +** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
1.6587 +** <dd>^This is the number of rows inserted into transient indices that
1.6588 +** were created automatically in order to help joins run faster.
1.6589 +** A non-zero value in this counter may indicate an opportunity to
1.6590 +** improvement performance by adding permanent indices that do not
1.6591 +** need to be reinitialized each time the statement is run.</dd>
1.6592 +**
1.6593 +** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
1.6594 +** <dd>^This is the number of virtual machine operations executed
1.6595 +** by the prepared statement if that number is less than or equal
1.6596 +** to 2147483647. The number of virtual machine operations can be
1.6597 +** used as a proxy for the total work done by the prepared statement.
1.6598 +** If the number of virtual machine operations exceeds 2147483647
1.6599 +** then the value returned by this statement status code is undefined.
1.6600 +** </dd>
1.6601 +** </dl>
1.6602 +*/
1.6603 +#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
1.6604 +#define SQLITE_STMTSTATUS_SORT 2
1.6605 +#define SQLITE_STMTSTATUS_AUTOINDEX 3
1.6606 +#define SQLITE_STMTSTATUS_VM_STEP 4
1.6607 +
1.6608 +/*
1.6609 +** CAPI3REF: Custom Page Cache Object
1.6610 +**
1.6611 +** The sqlite3_pcache type is opaque. It is implemented by
1.6612 +** the pluggable module. The SQLite core has no knowledge of
1.6613 +** its size or internal structure and never deals with the
1.6614 +** sqlite3_pcache object except by holding and passing pointers
1.6615 +** to the object.
1.6616 +**
1.6617 +** See [sqlite3_pcache_methods2] for additional information.
1.6618 +*/
1.6619 +typedef struct sqlite3_pcache sqlite3_pcache;
1.6620 +
1.6621 +/*
1.6622 +** CAPI3REF: Custom Page Cache Object
1.6623 +**
1.6624 +** The sqlite3_pcache_page object represents a single page in the
1.6625 +** page cache. The page cache will allocate instances of this
1.6626 +** object. Various methods of the page cache use pointers to instances
1.6627 +** of this object as parameters or as their return value.
1.6628 +**
1.6629 +** See [sqlite3_pcache_methods2] for additional information.
1.6630 +*/
1.6631 +typedef struct sqlite3_pcache_page sqlite3_pcache_page;
1.6632 +struct sqlite3_pcache_page {
1.6633 + void *pBuf; /* The content of the page */
1.6634 + void *pExtra; /* Extra information associated with the page */
1.6635 +};
1.6636 +
1.6637 +/*
1.6638 +** CAPI3REF: Application Defined Page Cache.
1.6639 +** KEYWORDS: {page cache}
1.6640 +**
1.6641 +** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
1.6642 +** register an alternative page cache implementation by passing in an
1.6643 +** instance of the sqlite3_pcache_methods2 structure.)^
1.6644 +** In many applications, most of the heap memory allocated by
1.6645 +** SQLite is used for the page cache.
1.6646 +** By implementing a
1.6647 +** custom page cache using this API, an application can better control
1.6648 +** the amount of memory consumed by SQLite, the way in which
1.6649 +** that memory is allocated and released, and the policies used to
1.6650 +** determine exactly which parts of a database file are cached and for
1.6651 +** how long.
1.6652 +**
1.6653 +** The alternative page cache mechanism is an
1.6654 +** extreme measure that is only needed by the most demanding applications.
1.6655 +** The built-in page cache is recommended for most uses.
1.6656 +**
1.6657 +** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
1.6658 +** internal buffer by SQLite within the call to [sqlite3_config]. Hence
1.6659 +** the application may discard the parameter after the call to
1.6660 +** [sqlite3_config()] returns.)^
1.6661 +**
1.6662 +** [[the xInit() page cache method]]
1.6663 +** ^(The xInit() method is called once for each effective
1.6664 +** call to [sqlite3_initialize()])^
1.6665 +** (usually only once during the lifetime of the process). ^(The xInit()
1.6666 +** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
1.6667 +** The intent of the xInit() method is to set up global data structures
1.6668 +** required by the custom page cache implementation.
1.6669 +** ^(If the xInit() method is NULL, then the
1.6670 +** built-in default page cache is used instead of the application defined
1.6671 +** page cache.)^
1.6672 +**
1.6673 +** [[the xShutdown() page cache method]]
1.6674 +** ^The xShutdown() method is called by [sqlite3_shutdown()].
1.6675 +** It can be used to clean up
1.6676 +** any outstanding resources before process shutdown, if required.
1.6677 +** ^The xShutdown() method may be NULL.
1.6678 +**
1.6679 +** ^SQLite automatically serializes calls to the xInit method,
1.6680 +** so the xInit method need not be threadsafe. ^The
1.6681 +** xShutdown method is only called from [sqlite3_shutdown()] so it does
1.6682 +** not need to be threadsafe either. All other methods must be threadsafe
1.6683 +** in multithreaded applications.
1.6684 +**
1.6685 +** ^SQLite will never invoke xInit() more than once without an intervening
1.6686 +** call to xShutdown().
1.6687 +**
1.6688 +** [[the xCreate() page cache methods]]
1.6689 +** ^SQLite invokes the xCreate() method to construct a new cache instance.
1.6690 +** SQLite will typically create one cache instance for each open database file,
1.6691 +** though this is not guaranteed. ^The
1.6692 +** first parameter, szPage, is the size in bytes of the pages that must
1.6693 +** be allocated by the cache. ^szPage will always a power of two. ^The
1.6694 +** second parameter szExtra is a number of bytes of extra storage
1.6695 +** associated with each page cache entry. ^The szExtra parameter will
1.6696 +** a number less than 250. SQLite will use the
1.6697 +** extra szExtra bytes on each page to store metadata about the underlying
1.6698 +** database page on disk. The value passed into szExtra depends
1.6699 +** on the SQLite version, the target platform, and how SQLite was compiled.
1.6700 +** ^The third argument to xCreate(), bPurgeable, is true if the cache being
1.6701 +** created will be used to cache database pages of a file stored on disk, or
1.6702 +** false if it is used for an in-memory database. The cache implementation
1.6703 +** does not have to do anything special based with the value of bPurgeable;
1.6704 +** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
1.6705 +** never invoke xUnpin() except to deliberately delete a page.
1.6706 +** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
1.6707 +** false will always have the "discard" flag set to true.
1.6708 +** ^Hence, a cache created with bPurgeable false will
1.6709 +** never contain any unpinned pages.
1.6710 +**
1.6711 +** [[the xCachesize() page cache method]]
1.6712 +** ^(The xCachesize() method may be called at any time by SQLite to set the
1.6713 +** suggested maximum cache-size (number of pages stored by) the cache
1.6714 +** instance passed as the first argument. This is the value configured using
1.6715 +** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
1.6716 +** parameter, the implementation is not required to do anything with this
1.6717 +** value; it is advisory only.
1.6718 +**
1.6719 +** [[the xPagecount() page cache methods]]
1.6720 +** The xPagecount() method must return the number of pages currently
1.6721 +** stored in the cache, both pinned and unpinned.
1.6722 +**
1.6723 +** [[the xFetch() page cache methods]]
1.6724 +** The xFetch() method locates a page in the cache and returns a pointer to
1.6725 +** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
1.6726 +** The pBuf element of the returned sqlite3_pcache_page object will be a
1.6727 +** pointer to a buffer of szPage bytes used to store the content of a
1.6728 +** single database page. The pExtra element of sqlite3_pcache_page will be
1.6729 +** a pointer to the szExtra bytes of extra storage that SQLite has requested
1.6730 +** for each entry in the page cache.
1.6731 +**
1.6732 +** The page to be fetched is determined by the key. ^The minimum key value
1.6733 +** is 1. After it has been retrieved using xFetch, the page is considered
1.6734 +** to be "pinned".
1.6735 +**
1.6736 +** If the requested page is already in the page cache, then the page cache
1.6737 +** implementation must return a pointer to the page buffer with its content
1.6738 +** intact. If the requested page is not already in the cache, then the
1.6739 +** cache implementation should use the value of the createFlag
1.6740 +** parameter to help it determined what action to take:
1.6741 +**
1.6742 +** <table border=1 width=85% align=center>
1.6743 +** <tr><th> createFlag <th> Behavior when page is not already in cache
1.6744 +** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
1.6745 +** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
1.6746 +** Otherwise return NULL.
1.6747 +** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
1.6748 +** NULL if allocating a new page is effectively impossible.
1.6749 +** </table>
1.6750 +**
1.6751 +** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
1.6752 +** will only use a createFlag of 2 after a prior call with a createFlag of 1
1.6753 +** failed.)^ In between the to xFetch() calls, SQLite may
1.6754 +** attempt to unpin one or more cache pages by spilling the content of
1.6755 +** pinned pages to disk and synching the operating system disk cache.
1.6756 +**
1.6757 +** [[the xUnpin() page cache method]]
1.6758 +** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
1.6759 +** as its second argument. If the third parameter, discard, is non-zero,
1.6760 +** then the page must be evicted from the cache.
1.6761 +** ^If the discard parameter is
1.6762 +** zero, then the page may be discarded or retained at the discretion of
1.6763 +** page cache implementation. ^The page cache implementation
1.6764 +** may choose to evict unpinned pages at any time.
1.6765 +**
1.6766 +** The cache must not perform any reference counting. A single
1.6767 +** call to xUnpin() unpins the page regardless of the number of prior calls
1.6768 +** to xFetch().
1.6769 +**
1.6770 +** [[the xRekey() page cache methods]]
1.6771 +** The xRekey() method is used to change the key value associated with the
1.6772 +** page passed as the second argument. If the cache
1.6773 +** previously contains an entry associated with newKey, it must be
1.6774 +** discarded. ^Any prior cache entry associated with newKey is guaranteed not
1.6775 +** to be pinned.
1.6776 +**
1.6777 +** When SQLite calls the xTruncate() method, the cache must discard all
1.6778 +** existing cache entries with page numbers (keys) greater than or equal
1.6779 +** to the value of the iLimit parameter passed to xTruncate(). If any
1.6780 +** of these pages are pinned, they are implicitly unpinned, meaning that
1.6781 +** they can be safely discarded.
1.6782 +**
1.6783 +** [[the xDestroy() page cache method]]
1.6784 +** ^The xDestroy() method is used to delete a cache allocated by xCreate().
1.6785 +** All resources associated with the specified cache should be freed. ^After
1.6786 +** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
1.6787 +** handle invalid, and will not use it with any other sqlite3_pcache_methods2
1.6788 +** functions.
1.6789 +**
1.6790 +** [[the xShrink() page cache method]]
1.6791 +** ^SQLite invokes the xShrink() method when it wants the page cache to
1.6792 +** free up as much of heap memory as possible. The page cache implementation
1.6793 +** is not obligated to free any memory, but well-behaved implementations should
1.6794 +** do their best.
1.6795 +*/
1.6796 +typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
1.6797 +struct sqlite3_pcache_methods2 {
1.6798 + int iVersion;
1.6799 + void *pArg;
1.6800 + int (*xInit)(void*);
1.6801 + void (*xShutdown)(void*);
1.6802 + sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
1.6803 + void (*xCachesize)(sqlite3_pcache*, int nCachesize);
1.6804 + int (*xPagecount)(sqlite3_pcache*);
1.6805 + sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
1.6806 + void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
1.6807 + void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
1.6808 + unsigned oldKey, unsigned newKey);
1.6809 + void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
1.6810 + void (*xDestroy)(sqlite3_pcache*);
1.6811 + void (*xShrink)(sqlite3_pcache*);
1.6812 +};
1.6813 +
1.6814 +/*
1.6815 +** This is the obsolete pcache_methods object that has now been replaced
1.6816 +** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
1.6817 +** retained in the header file for backwards compatibility only.
1.6818 +*/
1.6819 +typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
1.6820 +struct sqlite3_pcache_methods {
1.6821 + void *pArg;
1.6822 + int (*xInit)(void*);
1.6823 + void (*xShutdown)(void*);
1.6824 + sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
1.6825 + void (*xCachesize)(sqlite3_pcache*, int nCachesize);
1.6826 + int (*xPagecount)(sqlite3_pcache*);
1.6827 + void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
1.6828 + void (*xUnpin)(sqlite3_pcache*, void*, int discard);
1.6829 + void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
1.6830 + void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
1.6831 + void (*xDestroy)(sqlite3_pcache*);
1.6832 +};
1.6833 +
1.6834 +
1.6835 +/*
1.6836 +** CAPI3REF: Online Backup Object
1.6837 +**
1.6838 +** The sqlite3_backup object records state information about an ongoing
1.6839 +** online backup operation. ^The sqlite3_backup object is created by
1.6840 +** a call to [sqlite3_backup_init()] and is destroyed by a call to
1.6841 +** [sqlite3_backup_finish()].
1.6842 +**
1.6843 +** See Also: [Using the SQLite Online Backup API]
1.6844 +*/
1.6845 +typedef struct sqlite3_backup sqlite3_backup;
1.6846 +
1.6847 +/*
1.6848 +** CAPI3REF: Online Backup API.
1.6849 +**
1.6850 +** The backup API copies the content of one database into another.
1.6851 +** It is useful either for creating backups of databases or
1.6852 +** for copying in-memory databases to or from persistent files.
1.6853 +**
1.6854 +** See Also: [Using the SQLite Online Backup API]
1.6855 +**
1.6856 +** ^SQLite holds a write transaction open on the destination database file
1.6857 +** for the duration of the backup operation.
1.6858 +** ^The source database is read-locked only while it is being read;
1.6859 +** it is not locked continuously for the entire backup operation.
1.6860 +** ^Thus, the backup may be performed on a live source database without
1.6861 +** preventing other database connections from
1.6862 +** reading or writing to the source database while the backup is underway.
1.6863 +**
1.6864 +** ^(To perform a backup operation:
1.6865 +** <ol>
1.6866 +** <li><b>sqlite3_backup_init()</b> is called once to initialize the
1.6867 +** backup,
1.6868 +** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
1.6869 +** the data between the two databases, and finally
1.6870 +** <li><b>sqlite3_backup_finish()</b> is called to release all resources
1.6871 +** associated with the backup operation.
1.6872 +** </ol>)^
1.6873 +** There should be exactly one call to sqlite3_backup_finish() for each
1.6874 +** successful call to sqlite3_backup_init().
1.6875 +**
1.6876 +** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
1.6877 +**
1.6878 +** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
1.6879 +** [database connection] associated with the destination database
1.6880 +** and the database name, respectively.
1.6881 +** ^The database name is "main" for the main database, "temp" for the
1.6882 +** temporary database, or the name specified after the AS keyword in
1.6883 +** an [ATTACH] statement for an attached database.
1.6884 +** ^The S and M arguments passed to
1.6885 +** sqlite3_backup_init(D,N,S,M) identify the [database connection]
1.6886 +** and database name of the source database, respectively.
1.6887 +** ^The source and destination [database connections] (parameters S and D)
1.6888 +** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
1.6889 +** an error.
1.6890 +**
1.6891 +** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
1.6892 +** returned and an error code and error message are stored in the
1.6893 +** destination [database connection] D.
1.6894 +** ^The error code and message for the failed call to sqlite3_backup_init()
1.6895 +** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
1.6896 +** [sqlite3_errmsg16()] functions.
1.6897 +** ^A successful call to sqlite3_backup_init() returns a pointer to an
1.6898 +** [sqlite3_backup] object.
1.6899 +** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
1.6900 +** sqlite3_backup_finish() functions to perform the specified backup
1.6901 +** operation.
1.6902 +**
1.6903 +** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
1.6904 +**
1.6905 +** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
1.6906 +** the source and destination databases specified by [sqlite3_backup] object B.
1.6907 +** ^If N is negative, all remaining source pages are copied.
1.6908 +** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
1.6909 +** are still more pages to be copied, then the function returns [SQLITE_OK].
1.6910 +** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
1.6911 +** from source to destination, then it returns [SQLITE_DONE].
1.6912 +** ^If an error occurs while running sqlite3_backup_step(B,N),
1.6913 +** then an [error code] is returned. ^As well as [SQLITE_OK] and
1.6914 +** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
1.6915 +** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
1.6916 +** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
1.6917 +**
1.6918 +** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
1.6919 +** <ol>
1.6920 +** <li> the destination database was opened read-only, or
1.6921 +** <li> the destination database is using write-ahead-log journaling
1.6922 +** and the destination and source page sizes differ, or
1.6923 +** <li> the destination database is an in-memory database and the
1.6924 +** destination and source page sizes differ.
1.6925 +** </ol>)^
1.6926 +**
1.6927 +** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
1.6928 +** the [sqlite3_busy_handler | busy-handler function]
1.6929 +** is invoked (if one is specified). ^If the
1.6930 +** busy-handler returns non-zero before the lock is available, then
1.6931 +** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
1.6932 +** sqlite3_backup_step() can be retried later. ^If the source
1.6933 +** [database connection]
1.6934 +** is being used to write to the source database when sqlite3_backup_step()
1.6935 +** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
1.6936 +** case the call to sqlite3_backup_step() can be retried later on. ^(If
1.6937 +** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
1.6938 +** [SQLITE_READONLY] is returned, then
1.6939 +** there is no point in retrying the call to sqlite3_backup_step(). These
1.6940 +** errors are considered fatal.)^ The application must accept
1.6941 +** that the backup operation has failed and pass the backup operation handle
1.6942 +** to the sqlite3_backup_finish() to release associated resources.
1.6943 +**
1.6944 +** ^The first call to sqlite3_backup_step() obtains an exclusive lock
1.6945 +** on the destination file. ^The exclusive lock is not released until either
1.6946 +** sqlite3_backup_finish() is called or the backup operation is complete
1.6947 +** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
1.6948 +** sqlite3_backup_step() obtains a [shared lock] on the source database that
1.6949 +** lasts for the duration of the sqlite3_backup_step() call.
1.6950 +** ^Because the source database is not locked between calls to
1.6951 +** sqlite3_backup_step(), the source database may be modified mid-way
1.6952 +** through the backup process. ^If the source database is modified by an
1.6953 +** external process or via a database connection other than the one being
1.6954 +** used by the backup operation, then the backup will be automatically
1.6955 +** restarted by the next call to sqlite3_backup_step(). ^If the source
1.6956 +** database is modified by the using the same database connection as is used
1.6957 +** by the backup operation, then the backup database is automatically
1.6958 +** updated at the same time.
1.6959 +**
1.6960 +** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
1.6961 +**
1.6962 +** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
1.6963 +** application wishes to abandon the backup operation, the application
1.6964 +** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
1.6965 +** ^The sqlite3_backup_finish() interfaces releases all
1.6966 +** resources associated with the [sqlite3_backup] object.
1.6967 +** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
1.6968 +** active write-transaction on the destination database is rolled back.
1.6969 +** The [sqlite3_backup] object is invalid
1.6970 +** and may not be used following a call to sqlite3_backup_finish().
1.6971 +**
1.6972 +** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
1.6973 +** sqlite3_backup_step() errors occurred, regardless or whether or not
1.6974 +** sqlite3_backup_step() completed.
1.6975 +** ^If an out-of-memory condition or IO error occurred during any prior
1.6976 +** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
1.6977 +** sqlite3_backup_finish() returns the corresponding [error code].
1.6978 +**
1.6979 +** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
1.6980 +** is not a permanent error and does not affect the return value of
1.6981 +** sqlite3_backup_finish().
1.6982 +**
1.6983 +** [[sqlite3_backup__remaining()]] [[sqlite3_backup_pagecount()]]
1.6984 +** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
1.6985 +**
1.6986 +** ^Each call to sqlite3_backup_step() sets two values inside
1.6987 +** the [sqlite3_backup] object: the number of pages still to be backed
1.6988 +** up and the total number of pages in the source database file.
1.6989 +** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
1.6990 +** retrieve these two values, respectively.
1.6991 +**
1.6992 +** ^The values returned by these functions are only updated by
1.6993 +** sqlite3_backup_step(). ^If the source database is modified during a backup
1.6994 +** operation, then the values are not updated to account for any extra
1.6995 +** pages that need to be updated or the size of the source database file
1.6996 +** changing.
1.6997 +**
1.6998 +** <b>Concurrent Usage of Database Handles</b>
1.6999 +**
1.7000 +** ^The source [database connection] may be used by the application for other
1.7001 +** purposes while a backup operation is underway or being initialized.
1.7002 +** ^If SQLite is compiled and configured to support threadsafe database
1.7003 +** connections, then the source database connection may be used concurrently
1.7004 +** from within other threads.
1.7005 +**
1.7006 +** However, the application must guarantee that the destination
1.7007 +** [database connection] is not passed to any other API (by any thread) after
1.7008 +** sqlite3_backup_init() is called and before the corresponding call to
1.7009 +** sqlite3_backup_finish(). SQLite does not currently check to see
1.7010 +** if the application incorrectly accesses the destination [database connection]
1.7011 +** and so no error code is reported, but the operations may malfunction
1.7012 +** nevertheless. Use of the destination database connection while a
1.7013 +** backup is in progress might also also cause a mutex deadlock.
1.7014 +**
1.7015 +** If running in [shared cache mode], the application must
1.7016 +** guarantee that the shared cache used by the destination database
1.7017 +** is not accessed while the backup is running. In practice this means
1.7018 +** that the application must guarantee that the disk file being
1.7019 +** backed up to is not accessed by any connection within the process,
1.7020 +** not just the specific connection that was passed to sqlite3_backup_init().
1.7021 +**
1.7022 +** The [sqlite3_backup] object itself is partially threadsafe. Multiple
1.7023 +** threads may safely make multiple concurrent calls to sqlite3_backup_step().
1.7024 +** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
1.7025 +** APIs are not strictly speaking threadsafe. If they are invoked at the
1.7026 +** same time as another thread is invoking sqlite3_backup_step() it is
1.7027 +** possible that they return invalid values.
1.7028 +*/
1.7029 +SQLITE_API sqlite3_backup *sqlite3_backup_init(
1.7030 + sqlite3 *pDest, /* Destination database handle */
1.7031 + const char *zDestName, /* Destination database name */
1.7032 + sqlite3 *pSource, /* Source database handle */
1.7033 + const char *zSourceName /* Source database name */
1.7034 +);
1.7035 +SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
1.7036 +SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
1.7037 +SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
1.7038 +SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
1.7039 +
1.7040 +/*
1.7041 +** CAPI3REF: Unlock Notification
1.7042 +**
1.7043 +** ^When running in shared-cache mode, a database operation may fail with
1.7044 +** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
1.7045 +** individual tables within the shared-cache cannot be obtained. See
1.7046 +** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
1.7047 +** ^This API may be used to register a callback that SQLite will invoke
1.7048 +** when the connection currently holding the required lock relinquishes it.
1.7049 +** ^This API is only available if the library was compiled with the
1.7050 +** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
1.7051 +**
1.7052 +** See Also: [Using the SQLite Unlock Notification Feature].
1.7053 +**
1.7054 +** ^Shared-cache locks are released when a database connection concludes
1.7055 +** its current transaction, either by committing it or rolling it back.
1.7056 +**
1.7057 +** ^When a connection (known as the blocked connection) fails to obtain a
1.7058 +** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
1.7059 +** identity of the database connection (the blocking connection) that
1.7060 +** has locked the required resource is stored internally. ^After an
1.7061 +** application receives an SQLITE_LOCKED error, it may call the
1.7062 +** sqlite3_unlock_notify() method with the blocked connection handle as
1.7063 +** the first argument to register for a callback that will be invoked
1.7064 +** when the blocking connections current transaction is concluded. ^The
1.7065 +** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
1.7066 +** call that concludes the blocking connections transaction.
1.7067 +**
1.7068 +** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
1.7069 +** there is a chance that the blocking connection will have already
1.7070 +** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
1.7071 +** If this happens, then the specified callback is invoked immediately,
1.7072 +** from within the call to sqlite3_unlock_notify().)^
1.7073 +**
1.7074 +** ^If the blocked connection is attempting to obtain a write-lock on a
1.7075 +** shared-cache table, and more than one other connection currently holds
1.7076 +** a read-lock on the same table, then SQLite arbitrarily selects one of
1.7077 +** the other connections to use as the blocking connection.
1.7078 +**
1.7079 +** ^(There may be at most one unlock-notify callback registered by a
1.7080 +** blocked connection. If sqlite3_unlock_notify() is called when the
1.7081 +** blocked connection already has a registered unlock-notify callback,
1.7082 +** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
1.7083 +** called with a NULL pointer as its second argument, then any existing
1.7084 +** unlock-notify callback is canceled. ^The blocked connections
1.7085 +** unlock-notify callback may also be canceled by closing the blocked
1.7086 +** connection using [sqlite3_close()].
1.7087 +**
1.7088 +** The unlock-notify callback is not reentrant. If an application invokes
1.7089 +** any sqlite3_xxx API functions from within an unlock-notify callback, a
1.7090 +** crash or deadlock may be the result.
1.7091 +**
1.7092 +** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
1.7093 +** returns SQLITE_OK.
1.7094 +**
1.7095 +** <b>Callback Invocation Details</b>
1.7096 +**
1.7097 +** When an unlock-notify callback is registered, the application provides a
1.7098 +** single void* pointer that is passed to the callback when it is invoked.
1.7099 +** However, the signature of the callback function allows SQLite to pass
1.7100 +** it an array of void* context pointers. The first argument passed to
1.7101 +** an unlock-notify callback is a pointer to an array of void* pointers,
1.7102 +** and the second is the number of entries in the array.
1.7103 +**
1.7104 +** When a blocking connections transaction is concluded, there may be
1.7105 +** more than one blocked connection that has registered for an unlock-notify
1.7106 +** callback. ^If two or more such blocked connections have specified the
1.7107 +** same callback function, then instead of invoking the callback function
1.7108 +** multiple times, it is invoked once with the set of void* context pointers
1.7109 +** specified by the blocked connections bundled together into an array.
1.7110 +** This gives the application an opportunity to prioritize any actions
1.7111 +** related to the set of unblocked database connections.
1.7112 +**
1.7113 +** <b>Deadlock Detection</b>
1.7114 +**
1.7115 +** Assuming that after registering for an unlock-notify callback a
1.7116 +** database waits for the callback to be issued before taking any further
1.7117 +** action (a reasonable assumption), then using this API may cause the
1.7118 +** application to deadlock. For example, if connection X is waiting for
1.7119 +** connection Y's transaction to be concluded, and similarly connection
1.7120 +** Y is waiting on connection X's transaction, then neither connection
1.7121 +** will proceed and the system may remain deadlocked indefinitely.
1.7122 +**
1.7123 +** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
1.7124 +** detection. ^If a given call to sqlite3_unlock_notify() would put the
1.7125 +** system in a deadlocked state, then SQLITE_LOCKED is returned and no
1.7126 +** unlock-notify callback is registered. The system is said to be in
1.7127 +** a deadlocked state if connection A has registered for an unlock-notify
1.7128 +** callback on the conclusion of connection B's transaction, and connection
1.7129 +** B has itself registered for an unlock-notify callback when connection
1.7130 +** A's transaction is concluded. ^Indirect deadlock is also detected, so
1.7131 +** the system is also considered to be deadlocked if connection B has
1.7132 +** registered for an unlock-notify callback on the conclusion of connection
1.7133 +** C's transaction, where connection C is waiting on connection A. ^Any
1.7134 +** number of levels of indirection are allowed.
1.7135 +**
1.7136 +** <b>The "DROP TABLE" Exception</b>
1.7137 +**
1.7138 +** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
1.7139 +** always appropriate to call sqlite3_unlock_notify(). There is however,
1.7140 +** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
1.7141 +** SQLite checks if there are any currently executing SELECT statements
1.7142 +** that belong to the same connection. If there are, SQLITE_LOCKED is
1.7143 +** returned. In this case there is no "blocking connection", so invoking
1.7144 +** sqlite3_unlock_notify() results in the unlock-notify callback being
1.7145 +** invoked immediately. If the application then re-attempts the "DROP TABLE"
1.7146 +** or "DROP INDEX" query, an infinite loop might be the result.
1.7147 +**
1.7148 +** One way around this problem is to check the extended error code returned
1.7149 +** by an sqlite3_step() call. ^(If there is a blocking connection, then the
1.7150 +** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
1.7151 +** the special "DROP TABLE/INDEX" case, the extended error code is just
1.7152 +** SQLITE_LOCKED.)^
1.7153 +*/
1.7154 +SQLITE_API int sqlite3_unlock_notify(
1.7155 + sqlite3 *pBlocked, /* Waiting connection */
1.7156 + void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
1.7157 + void *pNotifyArg /* Argument to pass to xNotify */
1.7158 +);
1.7159 +
1.7160 +
1.7161 +/*
1.7162 +** CAP