/db/sqlite3/src/sqlite3.c
C | 10892 lines | 2863 code | 471 blank | 7558 comment | 37 complexity | f34bca82efdadb1451d829710755bce9 MD5 | raw file
Possible License(s): GPL-2.0, JSON, 0BSD, LGPL-3.0, AGPL-1.0, MIT, MPL-2.0-no-copyleft-exception, BSD-3-Clause, LGPL-2.1, Apache-2.0
- /******************************************************************************
- ** This file is an amalgamation of many separate C source files from SQLite
- ** version 3.7.11. By combining all the individual C code files into this
- ** single large file, the entire code can be compiled as a single translation
- ** unit. This allows many compilers to do optimizations that would not be
- ** possible if the files were compiled separately. Performance improvements
- ** of 5% or more are commonly seen when SQLite is compiled as a single
- ** translation unit.
- **
- ** This file is all you need to compile SQLite. To use SQLite in other
- ** programs, you need this file and the "sqlite3.h" header file that defines
- ** the programming interface to the SQLite library. (If you do not have
- ** the "sqlite3.h" header file at hand, you will find a copy embedded within
- ** the text of this file. Search for "Begin file sqlite3.h" to find the start
- ** of the embedded sqlite3.h header file.) Additional code files may be needed
- ** if you want a wrapper to interface SQLite with your choice of programming
- ** language. The code for the "sqlite3" command-line shell is also in a
- ** separate file. This file contains only code for the core SQLite library.
- */
- #define SQLITE_CORE 1
- #define SQLITE_AMALGAMATION 1
- #ifndef SQLITE_PRIVATE
- # define SQLITE_PRIVATE static
- #endif
- #ifndef SQLITE_API
- # define SQLITE_API
- #endif
- /************** Begin file sqliteInt.h ***************************************/
- /*
- ** 2001 September 15
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- ** Internal interface definitions for SQLite.
- **
- */
- #ifndef _SQLITEINT_H_
- #define _SQLITEINT_H_
- /*
- ** These #defines should enable >2GB file support on POSIX if the
- ** underlying operating system supports it. If the OS lacks
- ** large file support, or if the OS is windows, these should be no-ops.
- **
- ** Ticket #2739: The _LARGEFILE_SOURCE macro must appear before any
- ** system #includes. Hence, this block of code must be the very first
- ** code in all source files.
- **
- ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
- ** on the compiler command line. This is necessary if you are compiling
- ** on a recent machine (ex: Red Hat 7.2) but you want your code to work
- ** on an older machine (ex: Red Hat 6.0). If you compile on Red Hat 7.2
- ** without this option, LFS is enable. But LFS does not exist in the kernel
- ** in Red Hat 6.0, so the code won't work. Hence, for maximum binary
- ** portability you should omit LFS.
- **
- ** Similar is true for Mac OS X. LFS is only supported on Mac OS X 9 and later.
- */
- #ifndef SQLITE_DISABLE_LFS
- # define _LARGE_FILE 1
- # ifndef _FILE_OFFSET_BITS
- # define _FILE_OFFSET_BITS 64
- # endif
- # define _LARGEFILE_SOURCE 1
- #endif
- /*
- ** Include the configuration header output by 'configure' if we're using the
- ** autoconf-based build
- */
- #ifdef _HAVE_SQLITE_CONFIG_H
- #include "config.h"
- #endif
- /************** Include sqliteLimit.h in the middle of sqliteInt.h ***********/
- /************** Begin file sqliteLimit.h *************************************/
- /*
- ** 2007 May 7
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- **
- ** This file defines various limits of what SQLite can process.
- */
- /*
- ** The maximum length of a TEXT or BLOB in bytes. This also
- ** limits the size of a row in a table or index.
- **
- ** The hard limit is the ability of a 32-bit signed integer
- ** to count the size: 2^31-1 or 2147483647.
- */
- #ifndef SQLITE_MAX_LENGTH
- # define SQLITE_MAX_LENGTH 1000000000
- #endif
- /*
- ** This is the maximum number of
- **
- ** * Columns in a table
- ** * Columns in an index
- ** * Columns in a view
- ** * Terms in the SET clause of an UPDATE statement
- ** * Terms in the result set of a SELECT statement
- ** * Terms in the GROUP BY or ORDER BY clauses of a SELECT statement.
- ** * Terms in the VALUES clause of an INSERT statement
- **
- ** The hard upper limit here is 32676. Most database people will
- ** tell you that in a well-normalized database, you usually should
- ** not have more than a dozen or so columns in any table. And if
- ** that is the case, there is no point in having more than a few
- ** dozen values in any of the other situations described above.
- */
- #ifndef SQLITE_MAX_COLUMN
- # define SQLITE_MAX_COLUMN 2000
- #endif
- /*
- ** The maximum length of a single SQL statement in bytes.
- **
- ** It used to be the case that setting this value to zero would
- ** turn the limit off. That is no longer true. It is not possible
- ** to turn this limit off.
- */
- #ifndef SQLITE_MAX_SQL_LENGTH
- # define SQLITE_MAX_SQL_LENGTH 1000000000
- #endif
- /*
- ** The maximum depth of an expression tree. This is limited to
- ** some extent by SQLITE_MAX_SQL_LENGTH. But sometime you might
- ** want to place more severe limits on the complexity of an
- ** expression.
- **
- ** A value of 0 used to mean that the limit was not enforced.
- ** But that is no longer true. The limit is now strictly enforced
- ** at all times.
- */
- #ifndef SQLITE_MAX_EXPR_DEPTH
- # define SQLITE_MAX_EXPR_DEPTH 1000
- #endif
- /*
- ** The maximum number of terms in a compound SELECT statement.
- ** The code generator for compound SELECT statements does one
- ** level of recursion for each term. A stack overflow can result
- ** if the number of terms is too large. In practice, most SQL
- ** never has more than 3 or 4 terms. Use a value of 0 to disable
- ** any limit on the number of terms in a compount SELECT.
- */
- #ifndef SQLITE_MAX_COMPOUND_SELECT
- # define SQLITE_MAX_COMPOUND_SELECT 500
- #endif
- /*
- ** The maximum number of opcodes in a VDBE program.
- ** Not currently enforced.
- */
- #ifndef SQLITE_MAX_VDBE_OP
- # define SQLITE_MAX_VDBE_OP 25000
- #endif
- /*
- ** The maximum number of arguments to an SQL function.
- */
- #ifndef SQLITE_MAX_FUNCTION_ARG
- # define SQLITE_MAX_FUNCTION_ARG 127
- #endif
- /*
- ** The maximum number of in-memory pages to use for the main database
- ** table and for temporary tables. The SQLITE_DEFAULT_CACHE_SIZE
- */
- #ifndef SQLITE_DEFAULT_CACHE_SIZE
- # define SQLITE_DEFAULT_CACHE_SIZE 2000
- #endif
- #ifndef SQLITE_DEFAULT_TEMP_CACHE_SIZE
- # define SQLITE_DEFAULT_TEMP_CACHE_SIZE 500
- #endif
- /*
- ** The default number of frames to accumulate in the log file before
- ** checkpointing the database in WAL mode.
- */
- #ifndef SQLITE_DEFAULT_WAL_AUTOCHECKPOINT
- # define SQLITE_DEFAULT_WAL_AUTOCHECKPOINT 1000
- #endif
- /*
- ** The maximum number of attached databases. This must be between 0
- ** and 62. The upper bound on 62 is because a 64-bit integer bitmap
- ** is used internally to track attached databases.
- */
- #ifndef SQLITE_MAX_ATTACHED
- # define SQLITE_MAX_ATTACHED 10
- #endif
- /*
- ** The maximum value of a ?nnn wildcard that the parser will accept.
- */
- #ifndef SQLITE_MAX_VARIABLE_NUMBER
- # define SQLITE_MAX_VARIABLE_NUMBER 999
- #endif
- /* Maximum page size. The upper bound on this value is 65536. This a limit
- ** imposed by the use of 16-bit offsets within each page.
- **
- ** Earlier versions of SQLite allowed the user to change this value at
- ** compile time. This is no longer permitted, on the grounds that it creates
- ** a library that is technically incompatible with an SQLite library
- ** compiled with a different limit. If a process operating on a database
- ** with a page-size of 65536 bytes crashes, then an instance of SQLite
- ** compiled with the default page-size limit will not be able to rollback
- ** the aborted transaction. This could lead to database corruption.
- */
- #ifdef SQLITE_MAX_PAGE_SIZE
- # undef SQLITE_MAX_PAGE_SIZE
- #endif
- #define SQLITE_MAX_PAGE_SIZE 65536
- /*
- ** The default size of a database page.
- */
- #ifndef SQLITE_DEFAULT_PAGE_SIZE
- # define SQLITE_DEFAULT_PAGE_SIZE 1024
- #endif
- #if SQLITE_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
- # undef SQLITE_DEFAULT_PAGE_SIZE
- # define SQLITE_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
- #endif
- /*
- ** Ordinarily, if no value is explicitly provided, SQLite creates databases
- ** with page size SQLITE_DEFAULT_PAGE_SIZE. However, based on certain
- ** device characteristics (sector-size and atomic write() support),
- ** SQLite may choose a larger value. This constant is the maximum value
- ** SQLite will choose on its own.
- */
- #ifndef SQLITE_MAX_DEFAULT_PAGE_SIZE
- # define SQLITE_MAX_DEFAULT_PAGE_SIZE 8192
- #endif
- #if SQLITE_MAX_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
- # undef SQLITE_MAX_DEFAULT_PAGE_SIZE
- # define SQLITE_MAX_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
- #endif
- /*
- ** Maximum number of pages in one database file.
- **
- ** This is really just the default value for the max_page_count pragma.
- ** This value can be lowered (or raised) at run-time using that the
- ** max_page_count macro.
- */
- #ifndef SQLITE_MAX_PAGE_COUNT
- # define SQLITE_MAX_PAGE_COUNT 1073741823
- #endif
- /*
- ** Maximum length (in bytes) of the pattern in a LIKE or GLOB
- ** operator.
- */
- #ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
- # define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
- #endif
- /*
- ** Maximum depth of recursion for triggers.
- **
- ** A value of 1 means that a trigger program will not be able to itself
- ** fire any triggers. A value of 0 means that no trigger programs at all
- ** may be executed.
- */
- #ifndef SQLITE_MAX_TRIGGER_DEPTH
- # define SQLITE_MAX_TRIGGER_DEPTH 1000
- #endif
- /************** End of sqliteLimit.h *****************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /* Disable nuisance warnings on Borland compilers */
- #if defined(__BORLANDC__)
- #pragma warn -rch /* unreachable code */
- #pragma warn -ccc /* Condition is always true or false */
- #pragma warn -aus /* Assigned value is never used */
- #pragma warn -csu /* Comparing signed and unsigned */
- #pragma warn -spa /* Suspicious pointer arithmetic */
- #endif
- /* Needed for various definitions... */
- #ifndef _GNU_SOURCE
- # define _GNU_SOURCE
- #endif
- /*
- ** Include standard header files as necessary
- */
- #ifdef HAVE_STDINT_H
- #include <stdint.h>
- #endif
- #ifdef HAVE_INTTYPES_H
- #include <inttypes.h>
- #endif
- /*
- ** The following macros are used to cast pointers to integers and
- ** integers to pointers. The way you do this varies from one compiler
- ** to the next, so we have developed the following set of #if statements
- ** to generate appropriate macros for a wide range of compilers.
- **
- ** The correct "ANSI" way to do this is to use the intptr_t type.
- ** Unfortunately, that typedef is not available on all compilers, or
- ** if it is available, it requires an #include of specific headers
- ** that vary from one machine to the next.
- **
- ** Ticket #3860: The llvm-gcc-4.2 compiler from Apple chokes on
- ** the ((void*)&((char*)0)[X]) construct. But MSVC chokes on ((void*)(X)).
- ** So we have to define the macros in different ways depending on the
- ** compiler.
- */
- #if defined(__PTRDIFF_TYPE__) /* This case should work for GCC */
- # define SQLITE_INT_TO_PTR(X) ((void*)(__PTRDIFF_TYPE__)(X))
- # define SQLITE_PTR_TO_INT(X) ((int)(__PTRDIFF_TYPE__)(X))
- #elif !defined(__GNUC__) /* Works for compilers other than LLVM */
- # define SQLITE_INT_TO_PTR(X) ((void*)&((char*)0)[X])
- # define SQLITE_PTR_TO_INT(X) ((int)(((char*)X)-(char*)0))
- #elif defined(HAVE_STDINT_H) /* Use this case if we have ANSI headers */
- # define SQLITE_INT_TO_PTR(X) ((void*)(intptr_t)(X))
- # define SQLITE_PTR_TO_INT(X) ((int)(intptr_t)(X))
- #else /* Generates a warning - but it always works */
- # define SQLITE_INT_TO_PTR(X) ((void*)(X))
- # define SQLITE_PTR_TO_INT(X) ((int)(X))
- #endif
- /*
- ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
- ** 0 means mutexes are permanently disable and the library is never
- ** threadsafe. 1 means the library is serialized which is the highest
- ** level of threadsafety. 2 means the libary is multithreaded - multiple
- ** threads can use SQLite as long as no two threads try to use the same
- ** database connection at the same time.
- **
- ** Older versions of SQLite used an optional THREADSAFE macro.
- ** We support that for legacy.
- */
- #if !defined(SQLITE_THREADSAFE)
- #if defined(THREADSAFE)
- # define SQLITE_THREADSAFE THREADSAFE
- #else
- # define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
- #endif
- #endif
- /*
- ** Powersafe overwrite is on by default. But can be turned off using
- ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
- */
- #ifndef SQLITE_POWERSAFE_OVERWRITE
- # define SQLITE_POWERSAFE_OVERWRITE 1
- #endif
- /*
- ** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
- ** It determines whether or not the features related to
- ** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
- ** be overridden at runtime using the sqlite3_config() API.
- */
- #if !defined(SQLITE_DEFAULT_MEMSTATUS)
- # define SQLITE_DEFAULT_MEMSTATUS 1
- #endif
- /*
- ** Exactly one of the following macros must be defined in order to
- ** specify which memory allocation subsystem to use.
- **
- ** SQLITE_SYSTEM_MALLOC // Use normal system malloc()
- ** SQLITE_WIN32_MALLOC // Use Win32 native heap API
- ** SQLITE_MEMDEBUG // Debugging version of system malloc()
- **
- ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
- ** assert() macro is enabled, each call into the Win32 native heap subsystem
- ** will cause HeapValidate to be called. If heap validation should fail, an
- ** assertion will be triggered.
- **
- ** (Historical note: There used to be several other options, but we've
- ** pared it down to just these three.)
- **
- ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
- ** the default.
- */
- #if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_WIN32_MALLOC)+defined(SQLITE_MEMDEBUG)>1
- # error "At most one of the following compile-time configuration options\
- is allows: SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG"
- #endif
- #if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_WIN32_MALLOC)+defined(SQLITE_MEMDEBUG)==0
- # define SQLITE_SYSTEM_MALLOC 1
- #endif
- /*
- ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
- ** sizes of memory allocations below this value where possible.
- */
- #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
- # define SQLITE_MALLOC_SOFT_LIMIT 1024
- #endif
- /*
- ** We need to define _XOPEN_SOURCE as follows in order to enable
- ** recursive mutexes on most Unix systems. But Mac OS X is different.
- ** The _XOPEN_SOURCE define causes problems for Mac OS X we are told,
- ** so it is omitted there. See ticket #2673.
- **
- ** Later we learn that _XOPEN_SOURCE is poorly or incorrectly
- ** implemented on some systems. So we avoid defining it at all
- ** if it is already defined or if it is unneeded because we are
- ** not doing a threadsafe build. Ticket #2681.
- **
- ** See also ticket #2741.
- */
- #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE
- # define _XOPEN_SOURCE 500 /* Needed to enable pthread recursive mutexes */
- #endif
- /*
- ** The TCL headers are only needed when compiling the TCL bindings.
- */
- #if defined(SQLITE_TCL) || defined(TCLSH)
- # include <tcl.h>
- #endif
- /*
- ** Many people are failing to set -DNDEBUG=1 when compiling SQLite.
- ** Setting NDEBUG makes the code smaller and run faster. So the following
- ** lines are added to automatically set NDEBUG unless the -DSQLITE_DEBUG=1
- ** option is set. Thus NDEBUG becomes an opt-in rather than an opt-out
- ** feature.
- */
- #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
- # define NDEBUG 1
- #endif
- /*
- ** The testcase() macro is used to aid in coverage testing. When
- ** doing coverage testing, the condition inside the argument to
- ** testcase() must be evaluated both true and false in order to
- ** get full branch coverage. The testcase() macro is inserted
- ** to help ensure adequate test coverage in places where simple
- ** condition/decision coverage is inadequate. For example, testcase()
- ** can be used to make sure boundary values are tested. For
- ** bitmask tests, testcase() can be used to make sure each bit
- ** is significant and used at least once. On switch statements
- ** where multiple cases go to the same block of code, testcase()
- ** can insure that all cases are evaluated.
- **
- */
- #ifdef SQLITE_COVERAGE_TEST
- SQLITE_PRIVATE void sqlite3Coverage(int);
- # define testcase(X) if( X ){ sqlite3Coverage(__LINE__); }
- #else
- # define testcase(X)
- #endif
- /*
- ** The TESTONLY macro is used to enclose variable declarations or
- ** other bits of code that are needed to support the arguments
- ** within testcase() and assert() macros.
- */
- #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
- # define TESTONLY(X) X
- #else
- # define TESTONLY(X)
- #endif
- /*
- ** Sometimes we need a small amount of code such as a variable initialization
- ** to setup for a later assert() statement. We do not want this code to
- ** appear when assert() is disabled. The following macro is therefore
- ** used to contain that setup code. The "VVA" acronym stands for
- ** "Verification, Validation, and Accreditation". In other words, the
- ** code within VVA_ONLY() will only run during verification processes.
- */
- #ifndef NDEBUG
- # define VVA_ONLY(X) X
- #else
- # define VVA_ONLY(X)
- #endif
- /*
- ** The ALWAYS and NEVER macros surround boolean expressions which
- ** are intended to always be true or false, respectively. Such
- ** expressions could be omitted from the code completely. But they
- ** are included in a few cases in order to enhance the resilience
- ** of SQLite to unexpected behavior - to make the code "self-healing"
- ** or "ductile" rather than being "brittle" and crashing at the first
- ** hint of unplanned behavior.
- **
- ** In other words, ALWAYS and NEVER are added for defensive code.
- **
- ** When doing coverage testing ALWAYS and NEVER are hard-coded to
- ** be true and false so that the unreachable code then specify will
- ** not be counted as untested code.
- */
- #if defined(SQLITE_COVERAGE_TEST)
- # define ALWAYS(X) (1)
- # define NEVER(X) (0)
- #elif !defined(NDEBUG)
- # define ALWAYS(X) ((X)?1:(assert(0),0))
- # define NEVER(X) ((X)?(assert(0),1):0)
- #else
- # define ALWAYS(X) (X)
- # define NEVER(X) (X)
- #endif
- /*
- ** Return true (non-zero) if the input is a integer that is too large
- ** to fit in 32-bits. This macro is used inside of various testcase()
- ** macros to verify that we have tested SQLite for large-file support.
- */
- #define IS_BIG_INT(X) (((X)&~(i64)0xffffffff)!=0)
- /*
- ** The macro unlikely() is a hint that surrounds a boolean
- ** expression that is usually false. Macro likely() surrounds
- ** a boolean expression that is usually true. GCC is able to
- ** use these hints to generate better code, sometimes.
- */
- #if defined(__GNUC__) && 0
- # define likely(X) __builtin_expect((X),1)
- # define unlikely(X) __builtin_expect((X),0)
- #else
- # define likely(X) !!(X)
- # define unlikely(X) !!(X)
- #endif
- /************** Include sqlite3.h in the middle of sqliteInt.h ***************/
- /************** Begin file sqlite3.h *****************************************/
- /*
- ** 2001 September 15
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- ** This header file defines the interface that the SQLite library
- ** presents to client programs. If a C-function, structure, datatype,
- ** or constant definition does not appear in this file, then it is
- ** not a published API of SQLite, is subject to change without
- ** notice, and should not be referenced by programs that use SQLite.
- **
- ** Some of the definitions that are in this file are marked as
- ** "experimental". Experimental interfaces are normally new
- ** features recently added to SQLite. We do not anticipate changes
- ** to experimental interfaces but reserve the right to make minor changes
- ** if experience from use "in the wild" suggest such changes are prudent.
- **
- ** The official C-language API documentation for SQLite is derived
- ** from comments in this file. This file is the authoritative source
- ** on how SQLite interfaces are suppose to operate.
- **
- ** The name of this file under configuration management is "sqlite.h.in".
- ** The makefile makes some minor changes to this file (such as inserting
- ** the version number) and changes its name to "sqlite3.h" as
- ** part of the build process.
- */
- #ifndef _SQLITE3_H_
- #define _SQLITE3_H_
- #include <stdarg.h> /* Needed for the definition of va_list */
- /*
- ** Make sure we can call this stuff from C++.
- */
- #if 0
- extern "C" {
- #endif
- /*
- ** Add the ability to override 'extern'
- */
- #ifndef SQLITE_EXTERN
- # define SQLITE_EXTERN extern
- #endif
- #ifndef SQLITE_API
- # define SQLITE_API
- #endif
- /*
- ** These no-op macros are used in front of interfaces to mark those
- ** interfaces as either deprecated or experimental. New applications
- ** should not use deprecated interfaces - they are support for backwards
- ** compatibility only. Application writers should be aware that
- ** experimental interfaces are subject to change in point releases.
- **
- ** These macros used to resolve to various kinds of compiler magic that
- ** would generate warning messages when they were used. But that
- ** compiler magic ended up generating such a flurry of bug reports
- ** that we have taken it all out and gone back to using simple
- ** noop macros.
- */
- #define SQLITE_DEPRECATED
- #define SQLITE_EXPERIMENTAL
- /*
- ** Ensure these symbols were not defined by some previous header file.
- */
- #ifdef SQLITE_VERSION
- # undef SQLITE_VERSION
- #endif
- #ifdef SQLITE_VERSION_NUMBER
- # undef SQLITE_VERSION_NUMBER
- #endif
- /*
- ** CAPI3REF: Compile-Time Library Version Numbers
- **
- ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
- ** evaluates to a string literal that is the SQLite version in the
- ** format "X.Y.Z" where X is the major version number (always 3 for
- ** SQLite3) and Y is the minor version number and Z is the release number.)^
- ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
- ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
- ** numbers used in [SQLITE_VERSION].)^
- ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
- ** be larger than the release from which it is derived. Either Y will
- ** be held constant and Z will be incremented or else Y will be incremented
- ** and Z will be reset to zero.
- **
- ** Since version 3.6.18, SQLite source code has been stored in the
- ** <a href="http://www.fossil-scm.org/">Fossil configuration management
- ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
- ** a string which identifies a particular check-in of SQLite
- ** within its configuration management system. ^The SQLITE_SOURCE_ID
- ** string contains the date and time of the check-in (UTC) and an SHA1
- ** hash of the entire source tree.
- **
- ** See also: [sqlite3_libversion()],
- ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
- ** [sqlite_version()] and [sqlite_source_id()].
- */
- #define SQLITE_VERSION "3.7.11"
- #define SQLITE_VERSION_NUMBER 3007011
- #define SQLITE_SOURCE_ID "2012-03-20 11:35:50 00bb9c9ce4f465e6ac321ced2a9d0062dc364669"
- /*
- ** CAPI3REF: Run-Time Library Version Numbers
- ** KEYWORDS: sqlite3_version, sqlite3_sourceid
- **
- ** These interfaces provide the same information as the [SQLITE_VERSION],
- ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
- ** but are associated with the library instead of the header file. ^(Cautious
- ** programmers might include assert() statements in their application to
- ** verify that values returned by these interfaces match the macros in
- ** the header, and thus insure that the application is
- ** compiled with matching library and header files.
- **
- ** <blockquote><pre>
- ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
- ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
- ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
- ** </pre></blockquote>)^
- **
- ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
- ** macro. ^The sqlite3_libversion() function returns a pointer to the
- ** to the sqlite3_version[] string constant. The sqlite3_libversion()
- ** function is provided for use in DLLs since DLL users usually do not have
- ** direct access to string constants within the DLL. ^The
- ** sqlite3_libversion_number() function returns an integer equal to
- ** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
- ** a pointer to a string constant whose value is the same as the
- ** [SQLITE_SOURCE_ID] C preprocessor macro.
- **
- ** See also: [sqlite_version()] and [sqlite_source_id()].
- */
- SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
- SQLITE_API const char *sqlite3_libversion(void);
- SQLITE_API const char *sqlite3_sourceid(void);
- SQLITE_API int sqlite3_libversion_number(void);
- /*
- ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
- **
- ** ^The sqlite3_compileoption_used() function returns 0 or 1
- ** indicating whether the specified option was defined at
- ** compile time. ^The SQLITE_ prefix may be omitted from the
- ** option name passed to sqlite3_compileoption_used().
- **
- ** ^The sqlite3_compileoption_get() function allows iterating
- ** over the list of options that were defined at compile time by
- ** returning the N-th compile time option string. ^If N is out of range,
- ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
- ** prefix is omitted from any strings returned by
- ** sqlite3_compileoption_get().
- **
- ** ^Support for the diagnostic functions sqlite3_compileoption_used()
- ** and sqlite3_compileoption_get() may be omitted by specifying the
- ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
- **
- ** See also: SQL functions [sqlite_compileoption_used()] and
- ** [sqlite_compileoption_get()] and the [compile_options pragma].
- */
- #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
- SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
- SQLITE_API const char *sqlite3_compileoption_get(int N);
- #endif
- /*
- ** CAPI3REF: Test To See If The Library Is Threadsafe
- **
- ** ^The sqlite3_threadsafe() function returns zero if and only if
- ** SQLite was compiled with mutexing code omitted due to the
- ** [SQLITE_THREADSAFE] compile-time option being set to 0.
- **
- ** SQLite can be compiled with or without mutexes. When
- ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
- ** are enabled and SQLite is threadsafe. When the
- ** [SQLITE_THREADSAFE] macro is 0,
- ** the mutexes are omitted. Without the mutexes, it is not safe
- ** to use SQLite concurrently from more than one thread.
- **
- ** Enabling mutexes incurs a measurable performance penalty.
- ** So if speed is of utmost importance, it makes sense to disable
- ** the mutexes. But for maximum safety, mutexes should be enabled.
- ** ^The default behavior is for mutexes to be enabled.
- **
- ** This interface can be used by an application to make sure that the
- ** version of SQLite that it is linking against was compiled with
- ** the desired setting of the [SQLITE_THREADSAFE] macro.
- **
- ** This interface only reports on the compile-time mutex setting
- ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
- ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
- ** can be fully or partially disabled using a call to [sqlite3_config()]
- ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
- ** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
- ** sqlite3_threadsafe() function shows only the compile-time setting of
- ** thread safety, not any run-time changes to that setting made by
- ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
- ** is unchanged by calls to sqlite3_config().)^
- **
- ** See the [threading mode] documentation for additional information.
- */
- SQLITE_API int sqlite3_threadsafe(void);
- /*
- ** CAPI3REF: Database Connection Handle
- ** KEYWORDS: {database connection} {database connections}
- **
- ** Each open SQLite database is represented by a pointer to an instance of
- ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
- ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
- ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
- ** is its destructor. There are many other interfaces (such as
- ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
- ** [sqlite3_busy_timeout()] to name but three) that are methods on an
- ** sqlite3 object.
- */
- typedef struct sqlite3 sqlite3;
- /*
- ** CAPI3REF: 64-Bit Integer Types
- ** KEYWORDS: sqlite_int64 sqlite_uint64
- **
- ** Because there is no cross-platform way to specify 64-bit integer types
- ** SQLite includes typedefs for 64-bit signed and unsigned integers.
- **
- ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
- ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
- ** compatibility only.
- **
- ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
- ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
- ** sqlite3_uint64 and sqlite_uint64 types can store integer values
- ** between 0 and +18446744073709551615 inclusive.
- */
- #ifdef SQLITE_INT64_TYPE
- typedef SQLITE_INT64_TYPE sqlite_int64;
- typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
- #elif defined(_MSC_VER) || defined(__BORLANDC__)
- typedef __int64 sqlite_int64;
- typedef unsigned __int64 sqlite_uint64;
- #else
- typedef long long int sqlite_int64;
- typedef unsigned long long int sqlite_uint64;
- #endif
- typedef sqlite_int64 sqlite3_int64;
- typedef sqlite_uint64 sqlite3_uint64;
- /*
- ** If compiling for a processor that lacks floating point support,
- ** substitute integer for floating-point.
- */
- #ifdef SQLITE_OMIT_FLOATING_POINT
- # define double sqlite3_int64
- #endif
- /*
- ** CAPI3REF: Closing A Database Connection
- **
- ** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
- ** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
- ** successfully destroyed and all associated resources are deallocated.
- **
- ** Applications must [sqlite3_finalize | finalize] all [prepared statements]
- ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
- ** the [sqlite3] object prior to attempting to close the object. ^If
- ** sqlite3_close() is called on a [database connection] that still has
- ** outstanding [prepared statements] or [BLOB handles], then it returns
- ** SQLITE_BUSY.
- **
- ** ^If [sqlite3_close()] is invoked while a transaction is open,
- ** the transaction is automatically rolled back.
- **
- ** The C parameter to [sqlite3_close(C)] must be either a NULL
- ** pointer or an [sqlite3] object pointer obtained
- ** from [sqlite3_open()], [sqlite3_open16()], or
- ** [sqlite3_open_v2()], and not previously closed.
- ** ^Calling sqlite3_close() with a NULL pointer argument is a
- ** harmless no-op.
- */
- SQLITE_API int sqlite3_close(sqlite3 *);
- /*
- ** The type for a callback function.
- ** This is legacy and deprecated. It is included for historical
- ** compatibility and is not documented.
- */
- typedef int (*sqlite3_callback)(void*,int,char**, char**);
- /*
- ** CAPI3REF: One-Step Query Execution Interface
- **
- ** The sqlite3_exec() interface is a convenience wrapper around
- ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
- ** that allows an application to run multiple statements of SQL
- ** without having to use a lot of C code.
- **
- ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
- ** semicolon-separate SQL statements passed into its 2nd argument,
- ** in the context of the [database connection] passed in as its 1st
- ** argument. ^If the callback function of the 3rd argument to
- ** sqlite3_exec() is not NULL, then it is invoked for each result row
- ** coming out of the evaluated SQL statements. ^The 4th argument to
- ** sqlite3_exec() is relayed through to the 1st argument of each
- ** callback invocation. ^If the callback pointer to sqlite3_exec()
- ** is NULL, then no callback is ever invoked and result rows are
- ** ignored.
- **
- ** ^If an error occurs while evaluating the SQL statements passed into
- ** sqlite3_exec(), then execution of the current statement stops and
- ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
- ** is not NULL then any error message is written into memory obtained
- ** from [sqlite3_malloc()] and passed back through the 5th parameter.
- ** To avoid memory leaks, the application should invoke [sqlite3_free()]
- ** on error message strings returned through the 5th parameter of
- ** of sqlite3_exec() after the error message string is no longer needed.
- ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
- ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
- ** NULL before returning.
- **
- ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
- ** routine returns SQLITE_ABORT without invoking the callback again and
- ** without running any subsequent SQL statements.
- **
- ** ^The 2nd argument to the sqlite3_exec() callback function is the
- ** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
- ** callback is an array of pointers to strings obtained as if from
- ** [sqlite3_column_text()], one for each column. ^If an element of a
- ** result row is NULL then the corresponding string pointer for the
- ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
- ** sqlite3_exec() callback is an array of pointers to strings where each
- ** entry represents the name of corresponding result column as obtained
- ** from [sqlite3_column_name()].
- **
- ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
- ** to an empty string, or a pointer that contains only whitespace and/or
- ** SQL comments, then no SQL statements are evaluated and the database
- ** is not changed.
- **
- ** Restrictions:
- **
- ** <ul>
- ** <li> The application must insure that the 1st parameter to sqlite3_exec()
- ** is a valid and open [database connection].
- ** <li> The application must not close [database connection] specified by
- ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
- ** <li> The application must not modify the SQL statement text passed into
- ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
- ** </ul>
- */
- SQLITE_API int sqlite3_exec(
- sqlite3*, /* An open database */
- const char *sql, /* SQL to be evaluated */
- int (*callback)(void*,int,char**,char**), /* Callback function */
- void *, /* 1st argument to callback */
- char **errmsg /* Error msg written here */
- );
- /*
- ** CAPI3REF: Result Codes
- ** KEYWORDS: SQLITE_OK {error code} {error codes}
- ** KEYWORDS: {result code} {result codes}
- **
- ** Many SQLite functions return an integer result code from the set shown
- ** here in order to indicate success or failure.
- **
- ** New error codes may be added in future versions of SQLite.
- **
- ** See also: [SQLITE_IOERR_READ | extended result codes],
- ** [sqlite3_vtab_on_conflict()] [SQLITE_ROLLBACK | result codes].
- */
- #define SQLITE_OK 0 /* Successful result */
- /* beginning-of-error-codes */
- #define SQLITE_ERROR 1 /* SQL error or missing database */
- #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
- #define SQLITE_PERM 3 /* Access permission denied */
- #define SQLITE_ABORT 4 /* Callback routine requested an abort */
- #define SQLITE_BUSY 5 /* The database file is locked */
- #define SQLITE_LOCKED 6 /* A table in the database is locked */
- #define SQLITE_NOMEM 7 /* A malloc() failed */
- #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
- #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
- #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
- #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
- #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
- #define SQLITE_FULL 13 /* Insertion failed because database is full */
- #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
- #define SQLITE_PROTOCOL 15 /* Database lock protocol error */
- #define SQLITE_EMPTY 16 /* Database is empty */
- #define SQLITE_SCHEMA 17 /* The database schema changed */
- #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
- #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
- #define SQLITE_MISMATCH 20 /* Data type mismatch */
- #define SQLITE_MISUSE 21 /* Library used incorrectly */
- #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
- #define SQLITE_AUTH 23 /* Authorization denied */
- #define SQLITE_FORMAT 24 /* Auxiliary database format error */
- #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
- #define SQLITE_NOTADB 26 /* File opened that is not a database file */
- #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
- #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
- /* end-of-error-codes */
- /*
- ** CAPI3REF: Extended Result Codes
- ** KEYWORDS: {extended error code} {extended error codes}
- ** KEYWORDS: {extended result code} {extended result codes}
- **
- ** In its default configuration, SQLite API routines return one of 26 integer
- ** [SQLITE_OK | result codes]. However, experience has shown that many of
- ** these result codes are too coarse-grained. They do not provide as
- ** much information about problems as programmers might like. In an effort to
- ** address this, newer versions of SQLite (version 3.3.8 and later) include
- ** support for additional result codes that provide more detailed information
- ** about errors. The extended result codes are enabled or disabled
- ** on a per database connection basis using the
- ** [sqlite3_extended_result_codes()] API.
- **
- ** Some of the available extended result codes are listed here.
- ** One may expect the number of extended result codes will be expand
- ** over time. Software that uses extended result codes should expect
- ** to see new result codes in future releases of SQLite.
- **
- ** The SQLITE_OK result code will never be extended. It will always
- ** be exactly zero.
- */
- #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
- #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
- #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
- #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
- #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
- #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
- #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
- #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
- #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
- #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
- #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
- #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
- #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
- #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
- #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
- #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
- #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
- #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
- #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
- #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
- #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
- #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
- #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
- #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
- #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
- #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
- #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
- #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
- #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
- /*
- ** CAPI3REF: Flags For File Open Operations
- **
- ** These bit values are intended for use in the
- ** 3rd parameter to the [sqlite3_open_v2()] interface and
- ** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
- */
- #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
- #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
- #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
- #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
- #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
- #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
- #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
- #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
- #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
- #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
- #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
- #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
- #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
- #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
- #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
- #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
- #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
- #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
- #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
- /* Reserved: 0x00F00000 */
- /*
- ** CAPI3REF: Device Characteristics
- **
- ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
- ** object returns an integer which is a vector of the these
- ** bit values expressing I/O characteristics of the mass storage
- ** device that holds the file that the [sqlite3_io_methods]
- ** refers to.
- **
- ** The SQLITE_IOCAP_ATOMIC property means that all writes of
- ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
- ** mean that writes of blocks that are nnn bytes in size and
- ** are aligned to an address which is an integer multiple of
- ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
- ** that when data is appended to a file, the data is appended
- ** first then the size of the file is extended, never the other
- ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
- ** information is written to disk in the same order as calls
- ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
- ** after reboot following a crash or power loss, the only bytes in a
- ** file that were written at the application level might have changed
- ** and that adjacent bytes, even bytes within the same sector are
- ** guaranteed to be unchanged.
- */
- #define SQLITE_IOCAP_ATOMIC 0x00000001
- #define SQLITE_IOCAP_ATOMIC512 0x00000002
- #define SQLITE_IOCAP_ATOMIC1K 0x00000004
- #define SQLITE_IOCAP_ATOMIC2K 0x00000008
- #define SQLITE_IOCAP_ATOMIC4K 0x00000010
- #define SQLITE_IOCAP_ATOMIC8K 0x00000020
- #define SQLITE_IOCAP_ATOMIC16K 0x00000040
- #define SQLITE_IOCAP_ATOMIC32K 0x00000080
- #define SQLITE_IOCAP_ATOMIC64K 0x00000100
- #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
- #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
- #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
- #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
- /*
- ** CAPI3REF: File Locking Levels
- **
- ** SQLite uses one of these integer values as the second
- ** argument to calls it makes to the xLock() and xUnlock() methods
- ** of an [sqlite3_io_methods] object.
- */
- #define SQLITE_LOCK_NONE 0
- #define SQLITE_LOCK_SHARED 1
- #define SQLITE_LOCK_RESERVED 2
- #define SQLITE_LOCK_PENDING 3
- #define SQLITE_LOCK_EXCLUSIVE 4
- /*
- ** CAPI3REF: Synchronization Type Flags
- **
- ** When SQLite invokes the xSync() method of an
- ** [sqlite3_io_methods] object it uses a combination of
- ** these integer values as the second argument.
- **
- ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
- ** sync operation only needs to flush data to mass storage. Inode
- ** information need not be flushed. If the lower four bits of the flag
- ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
- ** If the lower four bits equal SQLITE_SYNC_FULL, that means
- ** to use Mac OS X style fullsync instead of fsync().
- **
- ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
- ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
- ** settings. The [synchronous pragma] determines when calls to the
- ** xSync VFS method occur and applies uniformly across all platforms.
- ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
- ** energetic or rigorous or forceful the sync operations are and
- ** only make a difference on Mac OSX for the default SQLite code.
- ** (Third-party VFS implementations might also make the distinction
- ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
- ** operating systems natively supported by SQLite, only Mac OSX
- ** cares about the difference.)
- */
- #define SQLITE_SYNC_NORMAL 0x00002
- #define SQLITE_SYNC_FULL 0x00003
- #define SQLITE_SYNC_DATAONLY 0x00010
- /*
- ** CAPI3REF: OS Interface Open File Handle
- **
- ** An [sqlite3_file] object represents an open file in the
- ** [sqlite3_vfs | OS interface layer]. Individual OS interface
- ** implementations will
- ** want to subclass this object by appending additional fields
- ** for their own use. The pMethods entry is a pointer to an
- ** [sqlite3_io_methods] object that defines methods for performing
- ** I/O operations on the open file.
- */
- typedef struct sqlite3_file sqlite3_file;
- struct sqlite3_file {
- const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
- };
- /*
- ** CAPI3REF: OS Interface File Virtual Methods Object
- **
- ** Every file opened by the [sqlite3_vfs.xOpen] method populates an
- ** [sqlite3_file] object (or, more commonly, a subclass of the
- ** [sqlite3_file] object) with a pointer to an instance of this object.
- ** This object defines the methods used to perform various operations
- ** against the open file represented by the [sqlite3_file] object.
- **
- ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
- ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
- ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
- ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
- ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
- ** to NULL.
- **
- ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
- ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
- ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
- ** flag may be ORed in to indicate that only the data of the file
- ** and not its inode needs to be synced.
- **
- ** The integer values to xLock() and xUnlock() are one of
- ** <ul>
- ** <li> [SQLITE_LOCK_NONE],
- ** <li> [SQLITE_LOCK_SHARED],
- ** <li> [SQLITE_LOCK_RESERVED],
- ** <li> [SQLITE_LOCK_PENDING], or
- ** <li> [SQLITE_LOCK_EXCLUSIVE].
- ** </ul>
- ** xLock() increases the lock. xUnlock() decreases the lock.
- ** The xCheckReservedLock() method checks whether any database connection,
- ** either in this process or in some other process, is holding a RESERVED,
- ** PENDING, or EXCLUSIVE lock on the file. It returns true
- ** if such a lock exists and false otherwise.
- **
- ** The xFileControl() method is a generic interface that allows custom
- ** VFS implementations to directly control an open file using the
- ** [sqlite3_file_control()] interface. The second "op" argument is an
- ** integer opcode. The third argument is a generic pointer intended to
- ** point to a structure that may contain arguments or space in which to
- ** write return values. Potential uses for xFileControl() might be
- ** functions to enable blocking locks with timeouts, to change the
- ** locking strategy (for example to use dot-file locks), to inquire
- ** about the status of a lock, or to break stale locks. The SQLite
- ** core reserves all opcodes less than 100 for its own use.
- ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
- ** Applications that define a custom xFileControl method should use opcodes
- ** greater than 100 to avoid conflicts. VFS implementations should
- ** return [SQLITE_NOTFOUND] for file control opcodes that they do not
- ** recognize.
- **
- ** The xSectorSize() method returns the sector size of the
- ** device that underlies the file. The sector size is the
- ** minimum write that can be performed without disturbing
- ** other bytes in the file. The xDeviceCharacteristics()
- ** method returns a bit vector describing behaviors of the
- ** underlying device:
- **
- ** <ul>
- ** <li> [SQLITE_IOCAP_ATOMIC]
- ** <li> [SQLITE_IOCAP_ATOMIC512]
- ** <li> [SQLITE_IOCAP_ATOMIC1K]
- ** <li> [SQLITE_IOCAP_ATOMIC2K]
- ** <li> [SQLITE_IOCAP_ATOMIC4K]
- ** <li> [SQLITE_IOCAP_ATOMIC8K]
- ** <li> [SQLITE_IOCAP_ATOMIC16K]
- ** <li> [SQLITE_IOCAP_ATOMIC32K]
- ** <li> [SQLITE_IOCAP_ATOMIC64K]
- ** <li> [SQLITE_IOCAP_SAFE_APPEND]
- ** <li> [SQLITE_IOCAP_SEQUENTIAL]
- ** </ul>
- **
- ** The SQLITE_IOCAP_ATOMIC property means that all writes of
- ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
- ** mean that writes of blocks that are nnn bytes in size and
- ** are aligned to an address which is an integer multiple of
- ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
- ** that when data is appended to a file, the data is appended
- ** first then the size of the file is extended, never the other
- ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
- ** information is written to disk in the same order as calls
- ** to xWrite().
- **
- ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
- ** in the unread portions of the buffer with zeros. A VFS that
- ** fails to zero-fill short reads might seem to work. However,
- ** failure to zero-fill short reads will eventually lead to
- ** database corruption.
- */
- typedef struct sqlite3_io_methods sqlite3_io_methods;
- struct sqlite3_io_methods {
- int iVersion;
- int (*xClose)(sqlite3_file*);
- int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
- int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
- int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
- int (*xSync)(sqlite3_file*, int flags);
- int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
- int (*xLock)(sqlite3_file*, int);
- int (*xUnlock)(sqlite3_file*, int);
- int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
- int (*xFileControl)(sqlite3_file*, int op, void *pArg);
- int (*xSectorSize)(sqlite3_file*);
- int (*xDeviceCharacteristics)(sqlite3_file*);
- /* Methods above are valid for version 1 */
- int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
- int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
- void (*xShmBarrier)(sqlite3_file*);
- int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
- /* Methods above are valid for version 2 */
- /* Additional methods may be added in future releases */
- };
- /*
- ** CAPI3REF: Standard File Control Opcodes
- **
- ** These integer constants are opcodes for the xFileControl method
- ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
- ** interface.
- **
- ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
- ** opcode causes the xFileControl method to write the current state of
- ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
- ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
- ** into an integer that the pArg argument points to. This capability
- ** is used during testing and only needs to be supported when SQLITE_TEST
- ** is defined.
- ** <ul>
- ** <li>[[SQLITE_FCNTL_SIZE_HINT]]
- ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
- ** layer a hint of how large the database file will grow to be during the
- ** current transaction. This hint is not guaranteed to be accurate but it
- ** is often close. The underlying VFS might choose to preallocate database
- ** file space based on this hint in order to help writes to the database
- ** file run faster.
- **
- ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
- ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
- ** extends and truncates the database file in chunks of a size specified
- ** by the user. The fourth argument to [sqlite3_file_control()] should
- ** point to an integer (type int) containing the new chunk-size to use
- ** for the nominated database. Allocating database file space in large
- ** chunks (say 1MB at a time), may reduce file-system fragmentation and
- ** improve performance on some systems.
- **
- ** <li>[[SQLITE_FCNTL_FILE_POINTER]]
- ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
- ** to the [sqlite3_file] object associated with a particular database
- ** connection. See the [sqlite3_file_control()] documentation for
- ** additional information.
- **
- ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
- ** ^(The [SQLITE_FCNTL_SYNC_OMITTED] opcode is generated internally by
- ** SQLite and sent to all VFSes in place of a call to the xSync method
- ** when the database connection has [PRAGMA synchronous] set to OFF.)^
- ** Some specialized VFSes need this signal in order to operate correctly
- ** when [PRAGMA synchronous | PRAGMA synchronous=OFF] is set, but most
- ** VFSes do not need this signal and should silently ignore this opcode.
- ** Applications should not call [sqlite3_file_control()] with this
- ** opcode as doing so may disrupt the operation of the specialized VFSes
- ** that do require it.
- **
- ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
- ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
- ** retry counts and intervals for certain disk I/O operations for the
- ** windows [VFS] in order to provide robustness in the presence of
- ** anti-virus programs. By default, the windows VFS will retry file read,
- ** file write, and file delete operations up to 10 times, with a delay
- ** of 25 milliseconds before the first retry and with the delay increasing
- ** by an additional 25 milliseconds with each subsequent retry. This
- ** opcode allows these two values (10 retries and 25 milliseconds of delay)
- ** to be adjusted. The values are changed for all database connections
- ** within the same process. The argument is a pointer to an array of two
- ** integers where the first integer i the new retry count and the second
- ** integer is the delay. If either integer is negative, then the setting
- ** is not changed but instead the prior value of that setting is written
- ** into the array entry, allowing the current retry settings to be
- ** interrogated. The zDbName parameter is ignored.
- **
- ** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
- ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
- ** persistent [WAL | Write AHead Log] setting. By default, the auxiliary
- ** write ahead log and shared memory files used for transaction control
- ** are automatically deleted when the latest connection to the database
- ** closes. Setting persistent WAL mode causes those files to persist after
- ** close. Persisting the files is useful when other processes that do not
- ** have write permission on the directory containing the database file want
- ** to read the database file, as the WAL and shared memory files must exist
- ** in order for the database to be readable. The fourth parameter to
- ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
- ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
- ** WAL mode. If the integer is -1, then it is overwritten with the current
- ** WAL persistence setting.
- **
- ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
- ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
- ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
- ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
- ** xDeviceCharacteristics methods. The fourth parameter to
- ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
- ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
- ** mode. If the integer is -1, then it is overwritten with the current
- ** zero-damage mode setting.
- **
- ** <li>[[SQLITE_FCNTL_OVERWRITE]]
- ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
- ** a write transaction to indicate that, unless it is rolled back for some
- ** reason, the entire database file will be overwritten by the current
- ** transaction. This is used by VACUUM operations.
- **
- ** <li>[[SQLITE_FCNTL_VFSNAME]]
- ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
- ** all [VFSes] in the VFS stack. The names are of all VFS shims and the
- ** final bottom-level VFS are written into memory obtained from
- ** [sqlite3_malloc()] and the result is stored in the char* variable
- ** that the fourth parameter of [sqlite3_file_control()] points to.
- ** The caller is responsible for freeing the memory when done. As with
- ** all file-control actions, there is no guarantee that this will actually
- ** do anything. Callers should initialize the char* variable to a NULL
- ** pointer in case this file-control is not implemented. This file-control
- ** is intended for diagnostic use only.
- **
- ** <li>[[SQLITE_FCNTL_PRAGMA]]
- ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
- ** file control is sent to the open [sqlite3_file] object corresponding
- ** to the database file to which the pragma statement refers. ^The argument
- ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
- ** pointers to strings (char**) in which the second element of the array
- ** is the name of the pragma and the third element is the argument to the
- ** pragma or NULL if the pragma has no argument. ^The handler for an
- ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
- ** of the char** argument point to a string obtained from [sqlite3_mprintf()]
- ** or the equivalent and that string will become the result of the pragma or
- ** the error message if the pragma fails. ^If the
- ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
- ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
- ** file control returns [SQLITE_OK], then the parser assumes that the
- ** VFS has handled the PRAGMA itself and the parser generates a no-op
- ** prepared statement. ^If the [SQLITE_FCNTL_PRAGMA] file control returns
- ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
- ** that the VFS encountered an error while handling the [PRAGMA] and the
- ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
- ** file control occurs at the beginning of pragma statement analysis and so
- ** it is able to override built-in [PRAGMA] statements.
- ** </ul>
- */
- #define SQLITE_FCNTL_LOCKSTATE 1
- #define SQLITE_GET_LOCKPROXYFILE 2
- #define SQLITE_SET_LOCKPROXYFILE 3
- #define SQLITE_LAST_ERRNO 4
- #define SQLITE_FCNTL_SIZE_HINT 5
- #define SQLITE_FCNTL_CHUNK_SIZE 6
- #define SQLITE_FCNTL_FILE_POINTER 7
- #define SQLITE_FCNTL_SYNC_OMITTED 8
- #define SQLITE_FCNTL_WIN32_AV_RETRY 9
- #define SQLITE_FCNTL_PERSIST_WAL 10
- #define SQLITE_FCNTL_OVERWRITE 11
- #define SQLITE_FCNTL_VFSNAME 12
- #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
- #define SQLITE_FCNTL_PRAGMA 14
- /*
- ** CAPI3REF: Mutex Handle
- **
- ** The mutex module within SQLite defines [sqlite3_mutex] to be an
- ** abstract type for a mutex object. The SQLite core never looks
- ** at the internal representation of an [sqlite3_mutex]. It only
- ** deals with pointers to the [sqlite3_mutex] object.
- **
- ** Mutexes are created using [sqlite3_mutex_alloc()].
- */
- typedef struct sqlite3_mutex sqlite3_mutex;
- /*
- ** CAPI3REF: OS Interface Object
- **
- ** An instance of the sqlite3_vfs object defines the interface between
- ** the SQLite core and the underlying operating system. The "vfs"
- ** in the name of the object stands for "virtual file system". See
- ** the [VFS | VFS documentation] for further information.
- **
- ** The value of the iVersion field is initially 1 but may be larger in
- ** future versions of SQLite. Additional fields may be appended to this
- ** object when the iVersion value is increased. Note that the structure
- ** of the sqlite3_vfs object changes in the transaction between
- ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
- ** modified.
- **
- ** The szOsFile field is the size of the subclassed [sqlite3_file]
- ** structure used by this VFS. mxPathname is the maximum length of
- ** a pathname in this VFS.
- **
- ** Registered sqlite3_vfs objects are kept on a linked list formed by
- ** the pNext pointer. The [sqlite3_vfs_register()]
- ** and [sqlite3_vfs_unregister()] interfaces manage this list
- ** in a thread-safe way. The [sqlite3_vfs_find()] interface
- ** searches the list. Neither the application code nor the VFS
- ** implementation should use the pNext pointer.
- **
- ** The pNext field is the only field in the sqlite3_vfs
- ** structure that SQLite will ever modify. SQLite will only access
- ** or modify this field while holding a particular static mutex.
- ** The application should never modify anything within the sqlite3_vfs
- ** object once the object has been registered.
- **
- ** The zName field holds the name of the VFS module. The name must
- ** be unique across all VFS modules.
- **
- ** [[sqlite3_vfs.xOpen]]
- ** ^SQLite guarantees that the zFilename parameter to xOpen
- ** is either a NULL pointer or string obtained
- ** from xFullPathname() with an optional suffix added.
- ** ^If a suffix is added to the zFilename parameter, it will
- ** consist of a single "-" character followed by no more than
- ** 11 alphanumeric and/or "-" characters.
- ** ^SQLite further guarantees that
- ** the string will be valid and unchanged until xClose() is
- ** called. Because of the previous sentence,
- ** the [sqlite3_file] can safely store a pointer to the
- ** filename if it needs to remember the filename for some reason.
- ** If the zFilename parameter to xOpen is a NULL pointer then xOpen
- ** must invent its own temporary name for the file. ^Whenever the
- ** xFilename parameter is NULL it will also be the case that the
- ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
- **
- ** The flags argument to xOpen() includes all bits set in
- ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
- ** or [sqlite3_open16()] is used, then flags includes at least
- ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
- ** If xOpen() opens a file read-only then it sets *pOutFlags to
- ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
- **
- ** ^(SQLite will also add one of the following flags to the xOpen()
- ** call, depending on the object being opened:
- **
- ** <ul>
- ** <li> [SQLITE_OPEN_MAIN_DB]
- ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
- ** <li> [SQLITE_OPEN_TEMP_DB]
- ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
- ** <li> [SQLITE_OPEN_TRANSIENT_DB]
- ** <li> [SQLITE_OPEN_SUBJOURNAL]
- ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
- ** <li> [SQLITE_OPEN_WAL]
- ** </ul>)^
- **
- ** The file I/O implementation can use the object type flags to
- ** change the way it deals with files. For example, an application
- ** that does not care about crash recovery or rollback might make
- ** the open of a journal file a no-op. Writes to this journal would
- ** also be no-ops, and any attempt to read the journal would return
- ** SQLITE_IOERR. Or the implementation might recognize that a database
- ** file will be doing page-aligned sector reads and writes in a random
- ** order and set up its I/O subsystem accordingly.
- **
- ** SQLite might also add one of the following flags to the xOpen method:
- **
- ** <ul>
- ** <li> [SQLITE_OPEN_DELETEONCLOSE]
- ** <li> [SQLITE_OPEN_EXCLUSIVE]
- ** </ul>
- **
- ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
- ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
- ** will be set for TEMP databases and their journals, transient
- ** databases, and subjournals.
- **
- ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
- ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
- ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
- ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
- ** SQLITE_OPEN_CREATE, is used to indicate that file should always
- ** be created, and that it is an error if it already exists.
- ** It is <i>not</i> used to indicate the file should be opened
- ** for exclusive access.
- **
- ** ^At least szOsFile bytes of memory are allocated by SQLite
- ** to hold the [sqlite3_file] structure passed as the third
- ** argument to xOpen. The xOpen method does not have to
- ** allocate the structure; it should just fill it in. Note that
- ** the xOpen method must set the sqlite3_file.pMethods to either
- ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
- ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
- ** element will be valid after xOpen returns regardless of the success
- ** or failure of the xOpen call.
- **
- ** [[sqlite3_vfs.xAccess]]
- ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
- ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
- ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
- ** to test whether a file is at least readable. The file can be a
- ** directory.
- **
- ** ^SQLite will always allocate at least mxPathname+1 bytes for the
- ** output buffer xFullPathname. The exact size of the output buffer
- ** is also passed as a parameter to both methods. If the output buffer
- ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
- ** handled as a fatal error by SQLite, vfs implementations should endeavor
- ** to prevent this by setting mxPathname to a sufficiently large value.
- **
- ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
- ** interfaces are not strictly a part of the filesystem, but they are
- ** included in the VFS structure for completeness.
- ** The xRandomness() function attempts to return nBytes bytes
- ** of good-quality randomness into zOut. The return value is
- ** the actual number of bytes of randomness obtained.
- ** The xSleep() method causes the calling thread to sleep for at
- ** least the number of microseconds given. ^The xCurrentTime()
- ** method returns a Julian Day Number for the current date and time as
- ** a floating point value.
- ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
- ** Day Number multiplied by 86400000 (the number of milliseconds in
- ** a 24-hour day).
- ** ^SQLite will use the xCurrentTimeInt64() method to get the current
- ** date and time if that method is available (if iVersion is 2 or
- ** greater and the function pointer is not NULL) and will fall back
- ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
- **
- ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
- ** are not used by the SQLite core. These optional interfaces are provided
- ** by some VFSes to facilitate testing of the VFS code. By overriding
- ** system calls with functions under its control, a test program can
- ** simulate faults and error conditions that would otherwise be difficult
- ** or impossible to induce. The set of system calls that can be overridden
- ** varies from one VFS to another, and from one version of the same VFS to the
- ** next. Applications that use these interfaces must be prepared for any
- ** or all of these interfaces to be NULL or for their behavior to change
- ** from one release to the next. Applications must not attempt to access
- ** any of these methods if the iVersion of the VFS is less than 3.
- */
- typedef struct sqlite3_vfs sqlite3_vfs;
- typedef void (*sqlite3_syscall_ptr)(void);
- struct sqlite3_vfs {
- int iVersion; /* Structure version number (currently 3) */
- int szOsFile; /* Size of subclassed sqlite3_file */
- int mxPathname; /* Maximum file pathname length */
- sqlite3_vfs *pNext; /* Next registered VFS */
- const char *zName; /* Name of this virtual file system */
- void *pAppData; /* Pointer to application-specific data */
- int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
- int flags, int *pOutFlags);
- int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
- int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
- int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
- void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
- void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
- void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
- void (*xDlClose)(sqlite3_vfs*, void*);
- int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
- int (*xSleep)(sqlite3_vfs*, int microseconds);
- int (*xCurrentTime)(sqlite3_vfs*, double*);
- int (*xGetLastError)(sqlite3_vfs*, int, char *);
- /*
- ** The methods above are in version 1 of the sqlite_vfs object
- ** definition. Those that follow are added in version 2 or later
- */
- int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
- /*
- ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
- ** Those below are for version 3 and greater.
- */
- int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
- sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
- const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
- /*
- ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
- ** New fields may be appended in figure versions. The iVersion
- ** value will increment whenever this happens.
- */
- };
- /*
- ** CAPI3REF: Flags for the xAccess VFS method
- **
- ** These integer constants can be used as the third parameter to
- ** the xAccess method of an [sqlite3_vfs] object. They determine
- ** what kind of permissions the xAccess method is looking for.
- ** With SQLITE_ACCESS_EXISTS, the xAccess method
- ** simply checks whether the file exists.
- ** With SQLITE_ACCESS_READWRITE, the xAccess method
- ** checks whether the named directory is both readable and writable
- ** (in other words, if files can be added, removed, and renamed within
- ** the directory).
- ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
- ** [temp_store_directory pragma], though this could change in a future
- ** release of SQLite.
- ** With SQLITE_ACCESS_READ, the xAccess method
- ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
- ** currently unused, though it might be used in a future release of
- ** SQLite.
- */
- #define SQLITE_ACCESS_EXISTS 0
- #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
- #define SQLITE_ACCESS_READ 2 /* Unused */
- /*
- ** CAPI3REF: Flags for the xShmLock VFS method
- **
- ** These integer constants define the various locking operations
- ** allowed by the xShmLock method of [sqlite3_io_methods]. The
- ** following are the only legal combinations of flags to the
- ** xShmLock method:
- **
- ** <ul>
- ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
- ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
- ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
- ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
- ** </ul>
- **
- ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
- ** was given no the corresponding lock.
- **
- ** The xShmLock method can transition between unlocked and SHARED or
- ** between unlocked and EXCLUSIVE. It cannot transition between SHARED
- ** and EXCLUSIVE.
- */
- #define SQLITE_SHM_UNLOCK 1
- #define SQLITE_SHM_LOCK 2
- #define SQLITE_SHM_SHARED 4
- #define SQLITE_SHM_EXCLUSIVE 8
- /*
- ** CAPI3REF: Maximum xShmLock index
- **
- ** The xShmLock method on [sqlite3_io_methods] may use values
- ** between 0 and this upper bound as its "offset" argument.
- ** The SQLite core will never attempt to acquire or release a
- ** lock outside of this range
- */
- #define SQLITE_SHM_NLOCK 8
- /*
- ** CAPI3REF: Initialize The SQLite Library
- **
- ** ^The sqlite3_initialize() routine initializes the
- ** SQLite library. ^The sqlite3_shutdown() routine
- ** deallocates any resources that were allocated by sqlite3_initialize().
- ** These routines are designed to aid in process initialization and
- ** shutdown on embedded systems. Workstation applications using
- ** SQLite normally do not need to invoke either of these routines.
- **
- ** A call to sqlite3_initialize() is an "effective" call if it is
- ** the first time sqlite3_initialize() is invoked during the lifetime of
- ** the process, or if it is the first time sqlite3_initialize() is invoked
- ** following a call to sqlite3_shutdown(). ^(Only an effective call
- ** of sqlite3_initialize() does any initialization. All other calls
- ** are harmless no-ops.)^
- **
- ** A call to sqlite3_shutdown() is an "effective" call if it is the first
- ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
- ** an effective call to sqlite3_shutdown() does any deinitialization.
- ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
- **
- ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
- ** is not. The sqlite3_shutdown() interface must only be called from a
- ** single thread. All open [database connections] must be closed and all
- ** other SQLite resources must be deallocated prior to invoking
- ** sqlite3_shutdown().
- **
- ** Among other things, ^sqlite3_initialize() will invoke
- ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
- ** will invoke sqlite3_os_end().
- **
- ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
- ** ^If for some reason, sqlite3_initialize() is unable to initialize
- ** the library (perhaps it is unable to allocate a needed resource such
- ** as a mutex) it returns an [error code] other than [SQLITE_OK].
- **
- ** ^The sqlite3_initialize() routine is called internally by many other
- ** SQLite interfaces so that an application usually does not need to
- ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
- ** calls sqlite3_initialize() so the SQLite library will be automatically
- ** initialized when [sqlite3_open()] is called if it has not be initialized
- ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
- ** compile-time option, then the automatic calls to sqlite3_initialize()
- ** are omitted and the application must call sqlite3_initialize() directly
- ** prior to using any other SQLite interface. For maximum portability,
- ** it is recommended that applications always invoke sqlite3_initialize()
- ** directly prior to using any other SQLite interface. Future releases
- ** of SQLite may require this. In other words, the behavior exhibited
- ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
- ** default behavior in some future release of SQLite.
- **
- ** The sqlite3_os_init() routine does operating-system specific
- ** initialization of the SQLite library. The sqlite3_os_end()
- ** routine undoes the effect of sqlite3_os_init(). Typical tasks
- ** performed by these routines include allocation or deallocation
- ** of static resources, initialization of global variables,
- ** setting up a default [sqlite3_vfs] module, or setting up
- ** a default configuration using [sqlite3_config()].
- **
- ** The application should never invoke either sqlite3_os_init()
- ** or sqlite3_os_end() directly. The application should only invoke
- ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
- ** interface is called automatically by sqlite3_initialize() and
- ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
- ** implementations for sqlite3_os_init() and sqlite3_os_end()
- ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
- ** When [custom builds | built for other platforms]
- ** (using the [SQLITE_OS_OTHER=1] compile-time
- ** option) the application must supply a suitable implementation for
- ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
- ** implementation of sqlite3_os_init() or sqlite3_os_end()
- ** must return [SQLITE_OK] on success and some other [error code] upon
- ** failure.
- */
- SQLITE_API int sqlite3_initialize(void);
- SQLITE_API int sqlite3_shutdown(void);
- SQLITE_API int sqlite3_os_init(void);
- SQLITE_API int sqlite3_os_end(void);
- /*
- ** CAPI3REF: Configuring The SQLite Library
- **
- ** The sqlite3_config() interface is used to make global configuration
- ** changes to SQLite in order to tune SQLite to the specific needs of
- ** the application. The default configuration is recommended for most
- ** applications and so this routine is usually not necessary. It is
- ** provided to support rare applications with unusual needs.
- **
- ** The sqlite3_config() interface is not threadsafe. The application
- ** must insure that no other SQLite interfaces are invoked by other
- ** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
- ** may only be invoked prior to library initialization using
- ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
- ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
- ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
- ** Note, however, that ^sqlite3_config() can be called as part of the
- ** implementation of an application-defined [sqlite3_os_init()].
- **
- ** The first argument to sqlite3_config() is an integer
- ** [configuration option] that determines
- ** what property of SQLite is to be configured. Subsequent arguments
- ** vary depending on the [configuration option]
- ** in the first argument.
- **
- ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
- ** ^If the option is unknown or SQLite is unable to set the option
- ** then this routine returns a non-zero [error code].
- */
- SQLITE_API int sqlite3_config(int, ...);
- /*
- ** CAPI3REF: Configure database connections
- **
- ** The sqlite3_db_config() interface is used to make configuration
- ** changes to a [database connection]. The interface is similar to
- ** [sqlite3_config()] except that the changes apply to a single
- ** [database connection] (specified in the first argument).
- **
- ** The second argument to sqlite3_db_config(D,V,...) is the
- ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
- ** that indicates what aspect of the [database connection] is being configured.
- ** Subsequent arguments vary depending on the configuration verb.
- **
- ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
- ** the call is considered successful.
- */
- SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
- /*
- ** CAPI3REF: Memory Allocation Routines
- **
- ** An instance of this object defines the interface between SQLite
- ** and low-level memory allocation routines.
- **
- ** This object is used in only one place in the SQLite interface.
- ** A pointer to an instance of this object is the argument to
- ** [sqlite3_config()] when the configuration option is
- ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
- ** By creating an instance of this object
- ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
- ** during configuration, an application can specify an alternative
- ** memory allocation subsystem for SQLite to use for all of its
- ** dynamic memory needs.
- **
- ** Note that SQLite comes with several [built-in memory allocators]
- ** that are perfectly adequate for the overwhelming majority of applications
- ** and that this object is only useful to a tiny minority of applications
- ** with specialized memory allocation requirements. This object is
- ** also used during testing of SQLite in order to specify an alternative
- ** memory allocator that simulates memory out-of-memory conditions in
- ** order to verify that SQLite recovers gracefully from such
- ** conditions.
- **
- ** The xMalloc, xRealloc, and xFree methods must work like the
- ** malloc(), realloc() and free() functions from the standard C library.
- ** ^SQLite guarantees that the second argument to
- ** xRealloc is always a value returned by a prior call to xRoundup.
- **
- ** xSize should return the allocated size of a memory allocation
- ** previously obtained from xMalloc or xRealloc. The allocated size
- ** is always at least as big as the requested size but may be larger.
- **
- ** The xRoundup method returns what would be the allocated size of
- ** a memory allocation given a particular requested size. Most memory
- ** allocators round up memory allocations at least to the next multiple
- ** of 8. Some allocators round up to a larger multiple or to a power of 2.
- ** Every memory allocation request coming in through [sqlite3_malloc()]
- ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
- ** that causes the corresponding memory allocation to fail.
- **
- ** The xInit method initializes the memory allocator. (For example,
- ** it might allocate any require mutexes or initialize internal data
- ** structures. The xShutdown method is invoked (indirectly) by
- ** [sqlite3_shutdown()] and should deallocate any resources acquired
- ** by xInit. The pAppData pointer is used as the only parameter to
- ** xInit and xShutdown.
- **
- ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
- ** the xInit method, so the xInit method need not be threadsafe. The
- ** xShutdown method is only called from [sqlite3_shutdown()] so it does
- ** not need to be threadsafe either. For all other methods, SQLite
- ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
- ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
- ** it is by default) and so the methods are automatically serialized.
- ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
- ** methods must be threadsafe or else make their own arrangements for
- ** serialization.
- **
- ** SQLite will never invoke xInit() more than once without an intervening
- ** call to xShutdown().
- */
- typedef struct sqlite3_mem_methods sqlite3_mem_methods;
- struct sqlite3_mem_methods {
- void *(*xMalloc)(int); /* Memory allocation function */
- void (*xFree)(void*); /* Free a prior allocation */
- void *(*xRealloc)(void*,int); /* Resize an allocation */
- int (*xSize)(void*); /* Return the size of an allocation */
- int (*xRoundup)(int); /* Round up request size to allocation size */
- int (*xInit)(void*); /* Initialize the memory allocator */
- void (*xShutdown)(void*); /* Deinitialize the memory allocator */
- void *pAppData; /* Argument to xInit() and xShutdown() */
- };
- /*
- ** CAPI3REF: Configuration Options
- ** KEYWORDS: {configuration option}
- **
- ** These constants are the available integer configuration options that
- ** can be passed as the first argument to the [sqlite3_config()] interface.
- **
- ** New configuration options may be added in future releases of SQLite.
- ** Existing configuration options might be discontinued. Applications
- ** should check the return code from [sqlite3_config()] to make sure that
- ** the call worked. The [sqlite3_config()] interface will return a
- ** non-zero [error code] if a discontinued or unsupported configuration option
- ** is invoked.
- **
- ** <dl>
- ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
- ** <dd>There are no arguments to this option. ^This option sets the
- ** [threading mode] to Single-thread. In other words, it disables
- ** all mutexing and puts SQLite into a mode where it can only be used
- ** by a single thread. ^If SQLite is compiled with
- ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
- ** it is not possible to change the [threading mode] from its default
- ** value of Single-thread and so [sqlite3_config()] will return
- ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
- ** configuration option.</dd>
- **
- ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
- ** <dd>There are no arguments to this option. ^This option sets the
- ** [threading mode] to Multi-thread. In other words, it disables
- ** mutexing on [database connection] and [prepared statement] objects.
- ** The application is responsible for serializing access to
- ** [database connections] and [prepared statements]. But other mutexes
- ** are enabled so that SQLite will be safe to use in a multi-threaded
- ** environment as long as no two threads attempt to use the same
- ** [database connection] at the same time. ^If SQLite is compiled with
- ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
- ** it is not possible to set the Multi-thread [threading mode] and
- ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
- ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
- **
- ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
- ** <dd>There are no arguments to this option. ^This option sets the
- ** [threading mode] to Serialized. In other words, this option enables
- ** all mutexes including the recursive
- ** mutexes on [database connection] and [prepared statement] objects.
- ** In this mode (which is the default when SQLite is compiled with
- ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
- ** to [database connections] and [prepared statements] so that the
- ** application is free to use the same [database connection] or the
- ** same [prepared statement] in different threads at the same time.
- ** ^If SQLite is compiled with
- ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
- ** it is not possible to set the Serialized [threading mode] and
- ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
- ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
- **
- ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
- ** <dd> ^(This option takes a single argument which is a pointer to an
- ** instance of the [sqlite3_mem_methods] structure. The argument specifies
- ** alternative low-level memory allocation routines to be used in place of
- ** the memory allocation routines built into SQLite.)^ ^SQLite makes
- ** its own private copy of the content of the [sqlite3_mem_methods] structure
- ** before the [sqlite3_config()] call returns.</dd>
- **
- ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
- ** <dd> ^(This option takes a single argument which is a pointer to an
- ** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
- ** structure is filled with the currently defined memory allocation routines.)^
- ** This option can be used to overload the default memory allocation
- ** routines with a wrapper that simulations memory allocation failure or
- ** tracks memory usage, for example. </dd>
- **
- ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
- ** <dd> ^This option takes single argument of type int, interpreted as a
- ** boolean, which enables or disables the collection of memory allocation
- ** statistics. ^(When memory allocation statistics are disabled, the
- ** following SQLite interfaces become non-operational:
- ** <ul>
- ** <li> [sqlite3_memory_used()]
- ** <li> [sqlite3_memory_highwater()]
- ** <li> [sqlite3_soft_heap_limit64()]
- ** <li> [sqlite3_status()]
- ** </ul>)^
- ** ^Memory allocation statistics are enabled by default unless SQLite is
- ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
- ** allocation statistics are disabled by default.
- ** </dd>
- **
- ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
- ** <dd> ^This option specifies a static memory buffer that SQLite can use for
- ** scratch memory. There are three arguments: A pointer an 8-byte
- ** aligned memory buffer from which the scratch allocations will be
- ** drawn, the size of each scratch allocation (sz),
- ** and the maximum number of scratch allocations (N). The sz
- ** argument must be a multiple of 16.
- ** The first argument must be a pointer to an 8-byte aligned buffer
- ** of at least sz*N bytes of memory.
- ** ^SQLite will use no more than two scratch buffers per thread. So
- ** N should be set to twice the expected maximum number of threads.
- ** ^SQLite will never require a scratch buffer that is more than 6
- ** times the database page size. ^If SQLite needs needs additional
- ** scratch memory beyond what is provided by this configuration option, then
- ** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
- **
- ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
- ** <dd> ^This option specifies a static memory buffer that SQLite can use for
- ** the database page cache with the default page cache implementation.
- ** This configuration should not be used if an application-define page
- ** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option.
- ** There are three arguments to this option: A pointer to 8-byte aligned
- ** memory, the size of each page buffer (sz), and the number of pages (N).
- ** The sz argument should be the size of the largest database page
- ** (a power of two between 512 and 32768) plus a little extra for each
- ** page header. ^The page header size is 20 to 40 bytes depending on
- ** the host architecture. ^It is harmless, apart from the wasted memory,
- ** to make sz a little too large. The first
- ** argument should point to an allocation of at least sz*N bytes of memory.
- ** ^SQLite will use the memory provided by the first argument to satisfy its
- ** memory needs for the first N pages that it adds to cache. ^If additional
- ** page cache memory is needed beyond what is provided by this option, then
- ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
- ** The pointer in the first argument must
- ** be aligned to an 8-byte boundary or subsequent behavior of SQLite
- ** will be undefined.</dd>
- **
- ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
- ** <dd> ^This option specifies a static memory buffer that SQLite will use
- ** for all of its dynamic memory allocation needs beyond those provided
- ** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
- ** There are three arguments: An 8-byte aligned pointer to the memory,
- ** the number of bytes in the memory buffer, and the minimum allocation size.
- ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
- ** to using its default memory allocator (the system malloc() implementation),
- ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
- ** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
- ** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
- ** allocator is engaged to handle all of SQLites memory allocation needs.
- ** The first pointer (the memory pointer) must be aligned to an 8-byte
- ** boundary or subsequent behavior of SQLite will be undefined.
- ** The minimum allocation size is capped at 2**12. Reasonable values
- ** for the minimum allocation size are 2**5 through 2**8.</dd>
- **
- ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
- ** <dd> ^(This option takes a single argument which is a pointer to an
- ** instance of the [sqlite3_mutex_methods] structure. The argument specifies
- ** alternative low-level mutex routines to be used in place
- ** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
- ** content of the [sqlite3_mutex_methods] structure before the call to
- ** [sqlite3_config()] returns. ^If SQLite is compiled with
- ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
- ** the entire mutexing subsystem is omitted from the build and hence calls to
- ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
- ** return [SQLITE_ERROR].</dd>
- **
- ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
- ** <dd> ^(This option takes a single argument which is a pointer to an
- ** instance of the [sqlite3_mutex_methods] structure. The
- ** [sqlite3_mutex_methods]
- ** structure is filled with the currently defined mutex routines.)^
- ** This option can be used to overload the default mutex allocation
- ** routines with a wrapper used to track mutex usage for performance
- ** profiling or testing, for example. ^If SQLite is compiled with
- ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
- ** the entire mutexing subsystem is omitted from the build and hence calls to
- ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
- ** return [SQLITE_ERROR].</dd>
- **
- ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
- ** <dd> ^(This option takes two arguments that determine the default
- ** memory allocation for the lookaside memory allocator on each
- ** [database connection]. The first argument is the
- ** size of each lookaside buffer slot and the second is the number of
- ** slots allocated to each database connection.)^ ^(This option sets the
- ** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
- ** verb to [sqlite3_db_config()] can be used to change the lookaside
- ** configuration on individual connections.)^ </dd>
- **
- ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
- ** <dd> ^(This option takes a single argument which is a pointer to
- ** an [sqlite3_pcache_methods2] object. This object specifies the interface
- ** to a custom page cache implementation.)^ ^SQLite makes a copy of the
- ** object and uses it for page cache memory allocations.</dd>
- **
- ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
- ** <dd> ^(This option takes a single argument which is a pointer to an
- ** [sqlite3_pcache_methods2] object. SQLite copies of the current
- ** page cache implementation into that object.)^ </dd>
- **
- ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
- ** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
- ** function with a call signature of void(*)(void*,int,const char*),
- ** and a pointer to void. ^If the function pointer is not NULL, it is
- ** invoked by [sqlite3_log()] to process each logging event. ^If the
- ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
- ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
- ** passed through as the first parameter to the application-defined logger
- ** function whenever that function is invoked. ^The second parameter to
- ** the logger function is a copy of the first parameter to the corresponding
- ** [sqlite3_log()] call and is intended to be a [result code] or an
- ** [extended result code]. ^The third parameter passed to the logger is
- ** log message after formatting via [sqlite3_snprintf()].
- ** The SQLite logging interface is not reentrant; the logger function
- ** supplied by the application must not invoke any SQLite interface.
- ** In a multi-threaded application, the application-defined logger
- ** function must be threadsafe. </dd>
- **
- ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
- ** <dd> This option takes a single argument of type int. If non-zero, then
- ** URI handling is globally enabled. If the parameter is zero, then URI handling
- ** is globally disabled. If URI handling is globally enabled, all filenames
- ** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
- ** specified as part of [ATTACH] commands are interpreted as URIs, regardless
- ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
- ** connection is opened. If it is globally disabled, filenames are
- ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
- ** database connection is opened. By default, URI handling is globally
- ** disabled. The default value may be changed by compiling with the
- ** [SQLITE_USE_URI] symbol defined.
- **
- ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
- ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFNIG_GETPCACHE
- ** <dd> These options are obsolete and should not be used by new code.
- ** They are retained for backwards compatibility but are now no-ops.
- ** </dl>
- */
- #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
- #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
- #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
- #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
- #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
- #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
- #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
- #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
- #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
- #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
- #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
- /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
- #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
- #define SQLITE_CONFIG_PCACHE 14 /* no-op */
- #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
- #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
- #define SQLITE_CONFIG_URI 17 /* int */
- #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
- #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
- /*
- ** CAPI3REF: Database Connection Configuration Options
- **
- ** These constants are the available integer configuration options that
- ** can be passed as the second argument to the [sqlite3_db_config()] interface.
- **
- ** New configuration options may be added in future releases of SQLite.
- ** Existing configuration options might be discontinued. Applications
- ** should check the return code from [sqlite3_db_config()] to make sure that
- ** the call worked. ^The [sqlite3_db_config()] interface will return a
- ** non-zero [error code] if a discontinued or unsupported configuration option
- ** is invoked.
- **
- ** <dl>
- ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
- ** <dd> ^This option takes three additional arguments that determine the
- ** [lookaside memory allocator] configuration for the [database connection].
- ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
- ** pointer to a memory buffer to use for lookaside memory.
- ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
- ** may be NULL in which case SQLite will allocate the
- ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
- ** size of each lookaside buffer slot. ^The third argument is the number of
- ** slots. The size of the buffer in the first argument must be greater than
- ** or equal to the product of the second and third arguments. The buffer
- ** must be aligned to an 8-byte boundary. ^If the second argument to
- ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
- ** rounded down to the next smaller multiple of 8. ^(The lookaside memory
- ** configuration for a database connection can only be changed when that
- ** connection is not currently using lookaside memory, or in other words
- ** when the "current value" returned by
- ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
- ** Any attempt to change the lookaside memory configuration when lookaside
- ** memory is in use leaves the configuration unchanged and returns
- ** [SQLITE_BUSY].)^</dd>
- **
- ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
- ** <dd> ^This option is used to enable or disable the enforcement of
- ** [foreign key constraints]. There should be two additional arguments.
- ** The first argument is an integer which is 0 to disable FK enforcement,
- ** positive to enable FK enforcement or negative to leave FK enforcement
- ** unchanged. The second parameter is a pointer to an integer into which
- ** is written 0 or 1 to indicate whether FK enforcement is off or on
- ** following this call. The second parameter may be a NULL pointer, in
- ** which case the FK enforcement setting is not reported back. </dd>
- **
- ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
- ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
- ** There should be two additional arguments.
- ** The first argument is an integer which is 0 to disable triggers,
- ** positive to enable triggers or negative to leave the setting unchanged.
- ** The second parameter is a pointer to an integer into which
- ** is written 0 or 1 to indicate whether triggers are disabled or enabled
- ** following this call. The second parameter may be a NULL pointer, in
- ** which case the trigger setting is not reported back. </dd>
- **
- ** </dl>
- */
- #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
- #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
- #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
- /*
- ** CAPI3REF: Enable Or Disable Extended Result Codes
- **
- ** ^The sqlite3_extended_result_codes() routine enables or disables the
- ** [extended result codes] feature of SQLite. ^The extended result
- ** codes are disabled by default for historical compatibility.
- */
- SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
- /*
- ** CAPI3REF: Last Insert Rowid
- **
- ** ^Each entry in an SQLite table has a unique 64-bit signed
- ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
- ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
- ** names are not also used by explicitly declared columns. ^If
- ** the table has a column of type [INTEGER PRIMARY KEY] then that column
- ** is another alias for the rowid.
- **
- ** ^This routine returns the [rowid] of the most recent
- ** successful [INSERT] into the database from the [database connection]
- ** in the first argument. ^As of SQLite version 3.7.7, this routines
- ** records the last insert rowid of both ordinary tables and [virtual tables].
- ** ^If no successful [INSERT]s
- ** have ever occurred on that database connection, zero is returned.
- **
- ** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
- ** method, then this routine will return the [rowid] of the inserted
- ** row as long as the trigger or virtual table method is running.
- ** But once the trigger or virtual table method ends, the value returned
- ** by this routine reverts to what it was before the trigger or virtual
- ** table method began.)^
- **
- ** ^An [INSERT] that fails due to a constraint violation is not a
- ** successful [INSERT] and does not change the value returned by this
- ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
- ** and INSERT OR ABORT make no changes to the return value of this
- ** routine when their insertion fails. ^(When INSERT OR REPLACE
- ** encounters a constraint violation, it does not fail. The
- ** INSERT continues to completion after deleting rows that caused
- ** the constraint problem so INSERT OR REPLACE will always change
- ** the return value of this interface.)^
- **
- ** ^For the purposes of this routine, an [INSERT] is considered to
- ** be successful even if it is subsequently rolled back.
- **
- ** This function is accessible to SQL statements via the
- ** [last_insert_rowid() SQL function].
- **
- ** If a separate thread performs a new [INSERT] on the same
- ** database connection while the [sqlite3_last_insert_rowid()]
- ** function is running and thus changes the last insert [rowid],
- ** then the value returned by [sqlite3_last_insert_rowid()] is
- ** unpredictable and might not equal either the old or the new
- ** last insert [rowid].
- */
- SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
- /*
- ** CAPI3REF: Count The Number Of Rows Modified
- **
- ** ^This function returns the number of database rows that were changed
- ** or inserted or deleted by the most recently completed SQL statement
- ** on the [database connection] specified by the first parameter.
- ** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
- ** or [DELETE] statement are counted. Auxiliary changes caused by
- ** triggers or [foreign key actions] are not counted.)^ Use the
- ** [sqlite3_total_changes()] function to find the total number of changes
- ** including changes caused by triggers and foreign key actions.
- **
- ** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
- ** are not counted. Only real table changes are counted.
- **
- ** ^(A "row change" is a change to a single row of a single table
- ** caused by an INSERT, DELETE, or UPDATE statement. Rows that
- ** are changed as side effects of [REPLACE] constraint resolution,
- ** rollback, ABORT processing, [DROP TABLE], or by any other
- ** mechanisms do not count as direct row changes.)^
- **
- ** A "trigger context" is a scope of execution that begins and
- ** ends with the script of a [CREATE TRIGGER | trigger].
- ** Most SQL statements are
- ** evaluated outside of any trigger. This is the "top level"
- ** trigger context. If a trigger fires from the top level, a
- ** new trigger context is entered for the duration of that one
- ** trigger. Subtriggers create subcontexts for their duration.
- **
- ** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
- ** not create a new trigger context.
- **
- ** ^This function returns the number of direct row changes in the
- ** most recent INSERT, UPDATE, or DELETE statement within the same
- ** trigger context.
- **
- ** ^Thus, when called from the top level, this function returns the
- ** number of changes in the most recent INSERT, UPDATE, or DELETE
- ** that also occurred at the top level. ^(Within the body of a trigger,
- ** the sqlite3_changes() interface can be called to find the number of
- ** changes in the most recently completed INSERT, UPDATE, or DELETE
- ** statement within the body of the same trigger.
- ** However, the number returned does not include changes
- ** caused by subtriggers since those have their own context.)^
- **
- ** See also the [sqlite3_total_changes()] interface, the
- ** [count_changes pragma], and the [changes() SQL function].
- **
- ** If a separate thread makes changes on the same database connection
- ** while [sqlite3_changes()] is running then the value returned
- ** is unpredictable and not meaningful.
- */
- SQLITE_API int sqlite3_changes(sqlite3*);
- /*
- ** CAPI3REF: Total Number Of Rows Modified
- **
- ** ^This function returns the number of row changes caused by [INSERT],
- ** [UPDATE] or [DELETE] statements since the [database connection] was opened.
- ** ^(The count returned by sqlite3_total_changes() includes all changes
- ** from all [CREATE TRIGGER | trigger] contexts and changes made by
- ** [foreign key actions]. However,
- ** the count does not include changes used to implement [REPLACE] constraints,
- ** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
- ** count does not include rows of views that fire an [INSTEAD OF trigger],
- ** though if the INSTEAD OF trigger makes changes of its own, those changes
- ** are counted.)^
- ** ^The sqlite3_total_changes() function counts the changes as soon as
- ** the statement that makes them is completed (when the statement handle
- ** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
- **
- ** See also the [sqlite3_changes()] interface, the
- ** [count_changes pragma], and the [total_changes() SQL function].
- **
- ** If a separate thread makes changes on the same database connection
- ** while [sqlite3_total_changes()] is running then the value
- ** returned is unpredictable and not meaningful.
- */
- SQLITE_API int sqlite3_total_changes(sqlite3*);
- /*
- ** CAPI3REF: Interrupt A Long-Running Query
- **
- ** ^This function causes any pending database operation to abort and
- ** return at its earliest opportunity. This routine is typically
- ** called in response to a user action such as pressing "Cancel"
- ** or Ctrl-C where the user wants a long query operation to halt
- ** immediately.
- **
- ** ^It is safe to call this routine from a thread different from the
- ** thread that is currently running the database operation. But it
- ** is not safe to call this routine with a [database connection] that
- ** is closed or might close before sqlite3_interrupt() returns.
- **
- ** ^If an SQL operation is very nearly finished at the time when
- ** sqlite3_interrupt() is called, then it might not have an opportunity
- ** to be interrupted and might continue to completion.
- **
- ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
- ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
- ** that is inside an explicit transaction, then the entire transaction
- ** will be rolled back automatically.
- **
- ** ^The sqlite3_interrupt(D) call is in effect until all currently running
- ** SQL statements on [database connection] D complete. ^Any new SQL statements
- ** that are started after the sqlite3_interrupt() call and before the
- ** running statements reaches zero are interrupted as if they had been
- ** running prior to the sqlite3_interrupt() call. ^New SQL statements
- ** that are started after the running statement count reaches zero are
- ** not effected by the sqlite3_interrupt().
- ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
- ** SQL statements is a no-op and has no effect on SQL statements
- ** that are started after the sqlite3_interrupt() call returns.
- **
- ** If the database connection closes while [sqlite3_interrupt()]
- ** is running then bad things will likely happen.
- */
- SQLITE_API void sqlite3_interrupt(sqlite3*);
- /*
- ** CAPI3REF: Determine If An SQL Statement Is Complete
- **
- ** These routines are useful during command-line input to determine if the
- ** currently entered text seems to form a complete SQL statement or
- ** if additional input is needed before sending the text into
- ** SQLite for parsing. ^These routines return 1 if the input string
- ** appears to be a complete SQL statement. ^A statement is judged to be
- ** complete if it ends with a semicolon token and is not a prefix of a
- ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
- ** string literals or quoted identifier names or comments are not
- ** independent tokens (they are part of the token in which they are
- ** embedded) and thus do not count as a statement terminator. ^Whitespace
- ** and comments that follow the final semicolon are ignored.
- **
- ** ^These routines return 0 if the statement is incomplete. ^If a
- ** memory allocation fails, then SQLITE_NOMEM is returned.
- **
- ** ^These routines do not parse the SQL statements thus
- ** will not detect syntactically incorrect SQL.
- **
- ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
- ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
- ** automatically by sqlite3_complete16(). If that initialization fails,
- ** then the return value from sqlite3_complete16() will be non-zero
- ** regardless of whether or not the input SQL is complete.)^
- **
- ** The input to [sqlite3_complete()] must be a zero-terminated
- ** UTF-8 string.
- **
- ** The input to [sqlite3_complete16()] must be a zero-terminated
- ** UTF-16 string in native byte order.
- */
- SQLITE_API int sqlite3_complete(const char *sql);
- SQLITE_API int sqlite3_complete16(const void *sql);
- /*
- ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
- **
- ** ^This routine sets a callback function that might be invoked whenever
- ** an attempt is made to open a database table that another thread
- ** or process has locked.
- **
- ** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
- ** is returned immediately upon encountering the lock. ^If the busy callback
- ** is not NULL, then the callback might be invoked with two arguments.
- **
- ** ^The first argument to the busy handler is a copy of the void* pointer which
- ** is the third argument to sqlite3_busy_handler(). ^The second argument to
- ** the busy handler callback is the number of times that the busy handler has
- ** been invoked for this locking event. ^If the
- ** busy callback returns 0, then no additional attempts are made to
- ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
- ** ^If the callback returns non-zero, then another attempt
- ** is made to open the database for reading and the cycle repeats.
- **
- ** The presence of a busy handler does not guarantee that it will be invoked
- ** when there is lock contention. ^If SQLite determines that invoking the busy
- ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
- ** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
- ** Consider a scenario where one process is holding a read lock that
- ** it is trying to promote to a reserved lock and
- ** a second process is holding a reserved lock that it is trying
- ** to promote to an exclusive lock. The first process cannot proceed
- ** because it is blocked by the second and the second process cannot
- ** proceed because it is blocked by the first. If both processes
- ** invoke the busy handlers, neither will make any progress. Therefore,
- ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
- ** will induce the first process to release its read lock and allow
- ** the second process to proceed.
- **
- ** ^The default busy callback is NULL.
- **
- ** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
- ** when SQLite is in the middle of a large transaction where all the
- ** changes will not fit into the in-memory cache. SQLite will
- ** already hold a RESERVED lock on the database file, but it needs
- ** to promote this lock to EXCLUSIVE so that it can spill cache
- ** pages into the database file without harm to concurrent
- ** readers. ^If it is unable to promote the lock, then the in-memory
- ** cache will be left in an inconsistent state and so the error
- ** code is promoted from the relatively benign [SQLITE_BUSY] to
- ** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion
- ** forces an automatic rollback of the changes. See the
- ** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
- ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
- ** this is important.
- **
- ** ^(There can only be a single busy handler defined for each
- ** [database connection]. Setting a new busy handler clears any
- ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
- ** will also set or clear the busy handler.
- **
- ** The busy callback should not take any actions which modify the
- ** database connection that invoked the busy handler. Any such actions
- ** result in undefined behavior.
- **
- ** A busy handler must not close the database connection
- ** or [prepared statement] that invoked the busy handler.
- */
- SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
- /*
- ** CAPI3REF: Set A Busy Timeout
- **
- ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
- ** for a specified amount of time when a table is locked. ^The handler
- ** will sleep multiple times until at least "ms" milliseconds of sleeping
- ** have accumulated. ^After at least "ms" milliseconds of sleeping,
- ** the handler returns 0 which causes [sqlite3_step()] to return
- ** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
- **
- ** ^Calling this routine with an argument less than or equal to zero
- ** turns off all busy handlers.
- **
- ** ^(There can only be a single busy handler for a particular
- ** [database connection] any any given moment. If another busy handler
- ** was defined (using [sqlite3_busy_handler()]) prior to calling
- ** this routine, that other busy handler is cleared.)^
- */
- SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
- /*
- ** CAPI3REF: Convenience Routines For Running Queries
- **
- ** This is a legacy interface that is preserved for backwards compatibility.
- ** Use of this interface is not recommended.
- **
- ** Definition: A <b>result table</b> is memory data structure created by the
- ** [sqlite3_get_table()] interface. A result table records the
- ** complete query results from one or more queries.
- **
- ** The table conceptually has a number of rows and columns. But
- ** these numbers are not part of the result table itself. These
- ** numbers are obtained separately. Let N be the number of rows
- ** and M be the number of columns.
- **
- ** A result table is an array of pointers to zero-terminated UTF-8 strings.
- ** There are (N+1)*M elements in the array. The first M pointers point
- ** to zero-terminated strings that contain the names of the columns.
- ** The remaining entries all point to query results. NULL values result
- ** in NULL pointers. All other values are in their UTF-8 zero-terminated
- ** string representation as returned by [sqlite3_column_text()].
- **
- ** A result table might consist of one or more memory allocations.
- ** It is not safe to pass a result table directly to [sqlite3_free()].
- ** A result table should be deallocated using [sqlite3_free_table()].
- **
- ** ^(As an example of the result table format, suppose a query result
- ** is as follows:
- **
- ** <blockquote><pre>
- ** Name | Age
- ** -----------------------
- ** Alice | 43
- ** Bob | 28
- ** Cindy | 21
- ** </pre></blockquote>
- **
- ** There are two column (M==2) and three rows (N==3). Thus the
- ** result table has 8 entries. Suppose the result table is stored
- ** in an array names azResult. Then azResult holds this content:
- **
- ** <blockquote><pre>
- ** azResult[0] = "Name";
- ** azResult[1] = "Age";
- ** azResult[2] = "Alice";
- ** azResult[3] = "43";
- ** azResult[4] = "Bob";
- ** azResult[5] = "28";
- ** azResult[6] = "Cindy";
- ** azResult[7] = "21";
- ** </pre></blockquote>)^
- **
- ** ^The sqlite3_get_table() function evaluates one or more
- ** semicolon-separated SQL statements in the zero-terminated UTF-8
- ** string of its 2nd parameter and returns a result table to the
- ** pointer given in its 3rd parameter.
- **
- ** After the application has finished with the result from sqlite3_get_table(),
- ** it must pass the result table pointer to sqlite3_free_table() in order to
- ** release the memory that was malloced. Because of the way the
- ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
- ** function must not try to call [sqlite3_free()] directly. Only
- ** [sqlite3_free_table()] is able to release the memory properly and safely.
- **
- ** The sqlite3_get_table() interface is implemented as a wrapper around
- ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
- ** to any internal data structures of SQLite. It uses only the public
- ** interface defined here. As a consequence, errors that occur in the
- ** wrapper layer outside of the internal [sqlite3_exec()] call are not
- ** reflected in subsequent calls to [sqlite3_errcode()] or
- ** [sqlite3_errmsg()].
- */
- SQLITE_API int sqlite3_get_table(
- sqlite3 *db, /* An open database */
- const char *zSql, /* SQL to be evaluated */
- char ***pazResult, /* Results of the query */
- int *pnRow, /* Number of result rows written here */
- int *pnColumn, /* Number of result columns written here */
- char **pzErrmsg /* Error msg written here */
- );
- SQLITE_API void sqlite3_free_table(char **result);
- /*
- ** CAPI3REF: Formatted String Printing Functions
- **
- ** These routines are work-alikes of the "printf()" family of functions
- ** from the standard C library.
- **
- ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
- ** results into memory obtained from [sqlite3_malloc()].
- ** The strings returned by these two routines should be
- ** released by [sqlite3_free()]. ^Both routines return a
- ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
- ** memory to hold the resulting string.
- **
- ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
- ** the standard C library. The result is written into the
- ** buffer supplied as the second parameter whose size is given by
- ** the first parameter. Note that the order of the
- ** first two parameters is reversed from snprintf().)^ This is an
- ** historical accident that cannot be fixed without breaking
- ** backwards compatibility. ^(Note also that sqlite3_snprintf()
- ** returns a pointer to its buffer instead of the number of
- ** characters actually written into the buffer.)^ We admit that
- ** the number of characters written would be a more useful return
- ** value but we cannot change the implementation of sqlite3_snprintf()
- ** now without breaking compatibility.
- **
- ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
- ** guarantees that the buffer is always zero-terminated. ^The first
- ** parameter "n" is the total size of the buffer, including space for
- ** the zero terminator. So the longest string that can be completely
- ** written will be n-1 characters.
- **
- ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
- **
- ** These routines all implement some additional formatting
- ** options that are useful for constructing SQL statements.
- ** All of the usual printf() formatting options apply. In addition, there
- ** is are "%q", "%Q", and "%z" options.
- **
- ** ^(The %q option works like %s in that it substitutes a nul-terminated
- ** string from the argument list. But %q also doubles every '\'' character.
- ** %q is designed for use inside a string literal.)^ By doubling each '\''
- ** character it escapes that character and allows it to be inserted into
- ** the string.
- **
- ** For example, assume the string variable zText contains text as follows:
- **
- ** <blockquote><pre>
- ** char *zText = "It's a happy day!";
- ** </pre></blockquote>
- **
- ** One can use this text in an SQL statement as follows:
- **
- ** <blockquote><pre>
- ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
- ** sqlite3_exec(db, zSQL, 0, 0, 0);
- ** sqlite3_free(zSQL);
- ** </pre></blockquote>
- **
- ** Because the %q format string is used, the '\'' character in zText
- ** is escaped and the SQL generated is as follows:
- **
- ** <blockquote><pre>
- ** INSERT INTO table1 VALUES('It''s a happy day!')
- ** </pre></blockquote>
- **
- ** This is correct. Had we used %s instead of %q, the generated SQL
- ** would have looked like this:
- **
- ** <blockquote><pre>
- ** INSERT INTO table1 VALUES('It's a happy day!');
- ** </pre></blockquote>
- **
- ** This second example is an SQL syntax error. As a general rule you should
- ** always use %q instead of %s when inserting text into a string literal.
- **
- ** ^(The %Q option works like %q except it also adds single quotes around
- ** the outside of the total string. Additionally, if the parameter in the
- ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
- ** single quotes).)^ So, for example, one could say:
- **
- ** <blockquote><pre>
- ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
- ** sqlite3_exec(db, zSQL, 0, 0, 0);
- ** sqlite3_free(zSQL);
- ** </pre></blockquote>
- **
- ** The code above will render a correct SQL statement in the zSQL
- ** variable even if the zText variable is a NULL pointer.
- **
- ** ^(The "%z" formatting option works like "%s" but with the
- ** addition that after the string has been read and copied into
- ** the result, [sqlite3_free()] is called on the input string.)^
- */
- SQLITE_API char *sqlite3_mprintf(const char*,...);
- SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
- SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
- SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
- /*
- ** CAPI3REF: Memory Allocation Subsystem
- **
- ** The SQLite core uses these three routines for all of its own
- ** internal memory allocation needs. "Core" in the previous sentence
- ** does not include operating-system specific VFS implementation. The
- ** Windows VFS uses native malloc() and free() for some operations.
- **
- ** ^The sqlite3_malloc() routine returns a pointer to a block
- ** of memory at least N bytes in length, where N is the parameter.
- ** ^If sqlite3_malloc() is unable to obtain sufficient free
- ** memory, it returns a NULL pointer. ^If the parameter N to
- ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
- ** a NULL pointer.
- **
- ** ^Calling sqlite3_free() with a pointer previously returned
- ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
- ** that it might be reused. ^The sqlite3_free() routine is
- ** a no-op if is called with a NULL pointer. Passing a NULL pointer
- ** to sqlite3_free() is harmless. After being freed, memory
- ** should neither be read nor written. Even reading previously freed
- ** memory might result in a segmentation fault or other severe error.
- ** Memory corruption, a segmentation fault, or other severe error
- ** might result if sqlite3_free() is called with a non-NULL pointer that
- ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
- **
- ** ^(The sqlite3_realloc() interface attempts to resize a
- ** prior memory allocation to be at least N bytes, where N is the
- ** second parameter. The memory allocation to be resized is the first
- ** parameter.)^ ^ If the first parameter to sqlite3_realloc()
- ** is a NULL pointer then its behavior is identical to calling
- ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
- ** ^If the second parameter to sqlite3_realloc() is zero or
- ** negative then the behavior is exactly the same as calling
- ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
- ** ^sqlite3_realloc() returns a pointer to a memory allocation
- ** of at least N bytes in size or NULL if sufficient memory is unavailable.
- ** ^If M is the size of the prior allocation, then min(N,M) bytes
- ** of the prior allocation are copied into the beginning of buffer returned
- ** by sqlite3_realloc() and the prior allocation is freed.
- ** ^If sqlite3_realloc() returns NULL, then the prior allocation
- ** is not freed.
- **
- ** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
- ** is always aligned to at least an 8 byte boundary, or to a
- ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
- ** option is used.
- **
- ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
- ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
- ** implementation of these routines to be omitted. That capability
- ** is no longer provided. Only built-in memory allocators can be used.
- **
- ** The Windows OS interface layer calls
- ** the system malloc() and free() directly when converting
- ** filenames between the UTF-8 encoding used by SQLite
- ** and whatever filename encoding is used by the particular Windows
- ** installation. Memory allocation errors are detected, but
- ** they are reported back as [SQLITE_CANTOPEN] or
- ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
- **
- ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
- ** must be either NULL or else pointers obtained from a prior
- ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
- ** not yet been released.
- **
- ** The application must not read or write any part of
- ** a block of memory after it has been released using
- ** [sqlite3_free()] or [sqlite3_realloc()].
- */
- SQLITE_API void *sqlite3_malloc(int);
- SQLITE_API void *sqlite3_realloc(void*, int);
- SQLITE_API void sqlite3_free(void*);
- /*
- ** CAPI3REF: Memory Allocator Statistics
- **
- ** SQLite provides these two interfaces for reporting on the status
- ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
- ** routines, which form the built-in memory allocation subsystem.
- **
- ** ^The [sqlite3_memory_used()] routine returns the number of bytes
- ** of memory currently outstanding (malloced but not freed).
- ** ^The [sqlite3_memory_highwater()] routine returns the maximum
- ** value of [sqlite3_memory_used()] since the high-water mark
- ** was last reset. ^The values returned by [sqlite3_memory_used()] and
- ** [sqlite3_memory_highwater()] include any overhead
- ** added by SQLite in its implementation of [sqlite3_malloc()],
- ** but not overhead added by the any underlying system library
- ** routines that [sqlite3_malloc()] may call.
- **
- ** ^The memory high-water mark is reset to the current value of
- ** [sqlite3_memory_used()] if and only if the parameter to
- ** [sqlite3_memory_highwater()] is true. ^The value returned
- ** by [sqlite3_memory_highwater(1)] is the high-water mark
- ** prior to the reset.
- */
- SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
- SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
- /*
- ** CAPI3REF: Pseudo-Random Number Generator
- **
- ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
- ** select random [ROWID | ROWIDs] when inserting new records into a table that
- ** already uses the largest possible [ROWID]. The PRNG is also used for
- ** the build-in random() and randomblob() SQL functions. This interface allows
- ** applications to access the same PRNG for other purposes.
- **
- ** ^A call to this routine stores N bytes of randomness into buffer P.
- **
- ** ^The first time this routine is invoked (either internally or by
- ** the application) the PRNG is seeded using randomness obtained
- ** from the xRandomness method of the default [sqlite3_vfs] object.
- ** ^On all subsequent invocations, the pseudo-randomness is generated
- ** internally and without recourse to the [sqlite3_vfs] xRandomness
- ** method.
- */
- SQLITE_API void sqlite3_randomness(int N, void *P);
- /*
- ** CAPI3REF: Compile-Time Authorization Callbacks
- **
- ** ^This routine registers an authorizer callback with a particular
- ** [database connection], supplied in the first argument.
- ** ^The authorizer callback is invoked as SQL statements are being compiled
- ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
- ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
- ** points during the compilation process, as logic is being created
- ** to perform various actions, the authorizer callback is invoked to
- ** see if those actions are allowed. ^The authorizer callback should
- ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
- ** specific action but allow the SQL statement to continue to be
- ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
- ** rejected with an error. ^If the authorizer callback returns
- ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
- ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
- ** the authorizer will fail with an error message.
- **
- ** When the callback returns [SQLITE_OK], that means the operation
- ** requested is ok. ^When the callback returns [SQLITE_DENY], the
- ** [sqlite3_prepare_v2()] or equivalent call that triggered the
- ** authorizer will fail with an error message explaining that
- ** access is denied.
- **
- ** ^The first parameter to the authorizer callback is a copy of the third
- ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
- ** to the callback is an integer [SQLITE_COPY | action code] that specifies
- ** the particular action to be authorized. ^The third through sixth parameters
- ** to the callback are zero-terminated strings that contain additional
- ** details about the action to be authorized.
- **
- ** ^If the action code is [SQLITE_READ]
- ** and the callback returns [SQLITE_IGNORE] then the
- ** [prepared statement] statement is constructed to substitute
- ** a NULL value in place of the table column that would have
- ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
- ** return can be used to deny an untrusted user access to individual
- ** columns of a table.
- ** ^If the action code is [SQLITE_DELETE] and the callback returns
- ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
- ** [truncate optimization] is disabled and all rows are deleted individually.
- **
- ** An authorizer is used when [sqlite3_prepare | preparing]
- ** SQL statements from an untrusted source, to ensure that the SQL statements
- ** do not try to access data they are not allowed to see, or that they do not
- ** try to execute malicious statements that damage the database. For
- ** example, an application may allow a user to enter arbitrary
- ** SQL queries for evaluation by a database. But the application does
- ** not want the user to be able to make arbitrary changes to the
- ** database. An authorizer could then be put in place while the
- ** user-entered SQL is being [sqlite3_prepare | prepared] that
- ** disallows everything except [SELECT] statements.
- **
- ** Applications that need to process SQL from untrusted sources
- ** might also consider lowering resource limits using [sqlite3_limit()]
- ** and limiting database size using the [max_page_count] [PRAGMA]
- ** in addition to using an authorizer.
- **
- ** ^(Only a single authorizer can be in place on a database connection
- ** at a time. Each call to sqlite3_set_authorizer overrides the
- ** previous call.)^ ^Disable the authorizer by installing a NULL callback.
- ** The authorizer is disabled by default.
- **
- ** The authorizer callback must not do anything that will modify
- ** the database connection that invoked the authorizer callback.
- ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
- ** database connections for the meaning of "modify" in this paragraph.
- **
- ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
- ** statement might be re-prepared during [sqlite3_step()] due to a
- ** schema change. Hence, the application should ensure that the
- ** correct authorizer callback remains in place during the [sqlite3_step()].
- **
- ** ^Note that the authorizer callback is invoked only during
- ** [sqlite3_prepare()] or its variants. Authorization is not
- ** performed during statement evaluation in [sqlite3_step()], unless
- ** as stated in the previous paragraph, sqlite3_step() invokes
- ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
- */
- SQLITE_API int sqlite3_set_authorizer(
- sqlite3*,
- int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
- void *pUserData
- );
- /*
- ** CAPI3REF: Authorizer Return Codes
- **
- ** The [sqlite3_set_authorizer | authorizer callback function] must
- ** return either [SQLITE_OK] or one of these two constants in order
- ** to signal SQLite whether or not the action is permitted. See the
- ** [sqlite3_set_authorizer | authorizer documentation] for additional
- ** information.
- **
- ** Note that SQLITE_IGNORE is also used as a [SQLITE_ROLLBACK | return code]
- ** from the [sqlite3_vtab_on_conflict()] interface.
- */
- #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
- #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
- /*
- ** CAPI3REF: Authorizer Action Codes
- **
- ** The [sqlite3_set_authorizer()] interface registers a callback function
- ** that is invoked to authorize certain SQL statement actions. The
- ** second parameter to the callback is an integer code that specifies
- ** what action is being authorized. These are the integer action codes that
- ** the authorizer callback may be passed.
- **
- ** These action code values signify what kind of operation is to be
- ** authorized. The 3rd and 4th parameters to the authorization
- ** callback function will be parameters or NULL depending on which of these
- ** codes is used as the second parameter. ^(The 5th parameter to the
- ** authorizer callback is the name of the database ("main", "temp",
- ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
- ** is the name of the inner-most trigger or view that is responsible for
- ** the access attempt or NULL if this access attempt is directly from
- ** top-level SQL code.
- */
- /******************************************* 3rd ************ 4th ***********/
- #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
- #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
- #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
- #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
- #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
- #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
- #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
- #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
- #define SQLITE_DELETE 9 /* Table Name NULL */
- #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
- #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
- #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
- #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
- #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
- #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
- #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
- #define SQLITE_DROP_VIEW 17 /* View Name NULL */
- #define SQLITE_INSERT 18 /* Table Name NULL */
- #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
- #define SQLITE_READ 20 /* Table Name Column Name */
- #define SQLITE_SELECT 21 /* NULL NULL */
- #define SQLITE_TRANSACTION 22 /* Operation NULL */
- #define SQLITE_UPDATE 23 /* Table Name Column Name */
- #define SQLITE_ATTACH 24 /* Filename NULL */
- #define SQLITE_DETACH 25 /* Database Name NULL */
- #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
- #define SQLITE_REINDEX 27 /* Index Name NULL */
- #define SQLITE_ANALYZE 28 /* Table Name NULL */
- #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
- #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
- #define SQLITE_FUNCTION 31 /* NULL Function Name */
- #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
- #define SQLITE_COPY 0 /* No longer used */
- /*
- ** CAPI3REF: Tracing And Profiling Functions
- **
- ** These routines register callback functions that can be used for
- ** tracing and profiling the execution of SQL statements.
- **
- ** ^The callback function registered by sqlite3_trace() is invoked at
- ** various times when an SQL statement is being run by [sqlite3_step()].
- ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
- ** SQL statement text as the statement first begins executing.
- ** ^(Additional sqlite3_trace() callbacks might occur
- ** as each triggered subprogram is entered. The callbacks for triggers
- ** contain a UTF-8 SQL comment that identifies the trigger.)^
- **
- ** ^The callback function registered by sqlite3_profile() is invoked
- ** as each SQL statement finishes. ^The profile callback contains
- ** the original statement text and an estimate of wall-clock time
- ** of how long that statement took to run. ^The profile callback
- ** time is in units of nanoseconds, however the current implementation
- ** is only capable of millisecond resolution so the six least significant
- ** digits in the time are meaningless. Future versions of SQLite
- ** might provide greater resolution on the profiler callback. The
- ** sqlite3_profile() function is considered experimental and is
- ** subject to change in future versions of SQLite.
- */
- SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
- SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
- void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
- /*
- ** CAPI3REF: Query Progress Callbacks
- **
- ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
- ** function X to be invoked periodically during long running calls to
- ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
- ** database connection D. An example use for this
- ** interface is to keep a GUI updated during a large query.
- **
- ** ^The parameter P is passed through as the only parameter to the
- ** callback function X. ^The parameter N is the number of
- ** [virtual machine instructions] that are evaluated between successive
- ** invocations of the callback X.
- **
- ** ^Only a single progress handler may be defined at one time per
- ** [database connection]; setting a new progress handler cancels the
- ** old one. ^Setting parameter X to NULL disables the progress handler.
- ** ^The progress handler is also disabled by setting N to a value less
- ** than 1.
- **
- ** ^If the progress callback returns non-zero, the operation is
- ** interrupted. This feature can be used to implement a
- ** "Cancel" button on a GUI progress dialog box.
- **
- ** The progress handler callback must not do anything that will modify
- ** the database connection that invoked the progress handler.
- ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
- ** database connections for the meaning of "modify" in this paragraph.
- **
- */
- SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
- /*
- ** CAPI3REF: Opening A New Database Connection
- **
- ** ^These routines open an SQLite database file as specified by the
- ** filename argument. ^The filename argument is interpreted as UTF-8 for
- ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
- ** order for sqlite3_open16(). ^(A [database connection] handle is usually
- ** returned in *ppDb, even if an error occurs. The only exception is that
- ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
- ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
- ** object.)^ ^(If the database is opened (and/or created) successfully, then
- ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
- ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
- ** an English language description of the error following a failure of any
- ** of the sqlite3_open() routines.
- **
- ** ^The default encoding for the database will be UTF-8 if
- ** sqlite3_open() or sqlite3_open_v2() is called and
- ** UTF-16 in the native byte order if sqlite3_open16() is used.
- **
- ** Whether or not an error occurs when it is opened, resources
- ** associated with the [database connection] handle should be released by
- ** passing it to [sqlite3_close()] when it is no longer required.
- **
- ** The sqlite3_open_v2() interface works like sqlite3_open()
- ** except that it accepts two additional parameters for additional control
- ** over the new database connection. ^(The flags parameter to
- ** sqlite3_open_v2() can take one of
- ** the following three values, optionally combined with the
- ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
- ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
- **
- ** <dl>
- ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
- ** <dd>The database is opened in read-only mode. If the database does not
- ** already exist, an error is returned.</dd>)^
- **
- ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
- ** <dd>The database is opened for reading and writing if possible, or reading
- ** only if the file is write protected by the operating system. In either
- ** case the database must already exist, otherwise an error is returned.</dd>)^
- **
- ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
- ** <dd>The database is opened for reading and writing, and is created if
- ** it does not already exist. This is the behavior that is always used for
- ** sqlite3_open() and sqlite3_open16().</dd>)^
- ** </dl>
- **
- ** If the 3rd parameter to sqlite3_open_v2() is not one of the
- ** combinations shown above optionally combined with other
- ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
- ** then the behavior is undefined.
- **
- ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
- ** opens in the multi-thread [threading mode] as long as the single-thread
- ** mode has not been set at compile-time or start-time. ^If the
- ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
- ** in the serialized [threading mode] unless single-thread was
- ** previously selected at compile-time or start-time.
- ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
- ** eligible to use [shared cache mode], regardless of whether or not shared
- ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
- ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
- ** participate in [shared cache mode] even if it is enabled.
- **
- ** ^The fourth parameter to sqlite3_open_v2() is the name of the
- ** [sqlite3_vfs] object that defines the operating system interface that
- ** the new database connection should use. ^If the fourth parameter is
- ** a NULL pointer then the default [sqlite3_vfs] object is used.
- **
- ** ^If the filename is ":memory:", then a private, temporary in-memory database
- ** is created for the connection. ^This in-memory database will vanish when
- ** the database connection is closed. Future versions of SQLite might
- ** make use of additional special filenames that begin with the ":" character.
- ** It is recommended that when a database filename actually does begin with
- ** a ":" character you should prefix the filename with a pathname such as
- ** "./" to avoid ambiguity.
- **
- ** ^If the filename is an empty string, then a private, temporary
- ** on-disk database will be created. ^This private database will be
- ** automatically deleted as soon as the database connection is closed.
- **
- ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
- **
- ** ^If [URI filename] interpretation is enabled, and the filename argument
- ** begins with "file:", then the filename is interpreted as a URI. ^URI
- ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
- ** set in the fourth argument to sqlite3_open_v2(), or if it has
- ** been enabled globally using the [SQLITE_CONFIG_URI] option with the
- ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
- ** As of SQLite version 3.7.7, URI filename interpretation is turned off
- ** by default, but future releases of SQLite might enable URI filename
- ** interpretation by default. See "[URI filenames]" for additional
- ** information.
- **
- ** URI filenames are parsed according to RFC 3986. ^If the URI contains an
- ** authority, then it must be either an empty string or the string
- ** "localhost". ^If the authority is not an empty string or "localhost", an
- ** error is returned to the caller. ^The fragment component of a URI, if
- ** present, is ignored.
- **
- ** ^SQLite uses the path component of the URI as the name of the disk file
- ** which contains the database. ^If the path begins with a '/' character,
- ** then it is interpreted as an absolute path. ^If the path does not begin
- ** with a '/' (meaning that the authority section is omitted from the URI)
- ** then the path is interpreted as a relative path.
- ** ^On windows, the first component of an absolute path
- ** is a drive specification (e.g. "C:").
- **
- ** [[core URI query parameters]]
- ** The query component of a URI may contain parameters that are interpreted
- ** either by SQLite itself, or by a [VFS | custom VFS implementation].
- ** SQLite interprets the following three query parameters:
- **
- ** <ul>
- ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
- ** a VFS object that provides the operating system interface that should
- ** be used to access the database file on disk. ^If this option is set to
- ** an empty string the default VFS object is used. ^Specifying an unknown
- ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
- ** present, then the VFS specified by the option takes precedence over
- ** the value passed as the fourth parameter to sqlite3_open_v2().
- **
- ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw" or
- ** "rwc". Attempting to set it to any other value is an error)^.
- ** ^If "ro" is specified, then the database is opened for read-only
- ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
- ** third argument to sqlite3_prepare_v2(). ^If the mode option is set to
- ** "rw", then the database is opened for read-write (but not create)
- ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
- ** been set. ^Value "rwc" is equivalent to setting both
- ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If sqlite3_open_v2() is
- ** used, it is an error to specify a value for the mode parameter that is
- ** less restrictive than that specified by the flags passed as the third
- ** parameter.
- **
- ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
- ** "private". ^Setting it to "shared" is equivalent to setting the
- ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
- ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
- ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
- ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
- ** a URI filename, its value overrides any behaviour requested by setting
- ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
- ** </ul>
- **
- ** ^Specifying an unknown parameter in the query component of a URI is not an
- ** error. Future versions of SQLite might understand additional query
- ** parameters. See "[query parameters with special meaning to SQLite]" for
- ** additional information.
- **
- ** [[URI filename examples]] <h3>URI filename examples</h3>
- **
- ** <table border="1" align=center cellpadding=5>
- ** <tr><th> URI filenames <th> Results
- ** <tr><td> file:data.db <td>
- ** Open the file "data.db" in the current directory.
- ** <tr><td> file:/home/fred/data.db<br>
- ** file:///home/fred/data.db <br>
- ** file://localhost/home/fred/data.db <br> <td>
- ** Open the database file "/home/fred/data.db".
- ** <tr><td> file://darkstar/home/fred/data.db <td>
- ** An error. "darkstar" is not a recognized authority.
- ** <tr><td style="white-space:nowrap">
- ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
- ** <td> Windows only: Open the file "data.db" on fred's desktop on drive
- ** C:. Note that the %20 escaping in this example is not strictly
- ** necessary - space characters can be used literally
- ** in URI filenames.
- ** <tr><td> file:data.db?mode=ro&cache=private <td>
- ** Open file "data.db" in the current directory for read-only access.
- ** Regardless of whether or not shared-cache mode is enabled by
- ** default, use a private cache.
- ** <tr><td> file:/home/fred/data.db?vfs=unix-nolock <td>
- ** Open file "/home/fred/data.db". Use the special VFS "unix-nolock".
- ** <tr><td> file:data.db?mode=readonly <td>
- ** An error. "readonly" is not a valid option for the "mode" parameter.
- ** </table>
- **
- ** ^URI hexadecimal escape sequences (%HH) are supported within the path and
- ** query components of a URI. A hexadecimal escape sequence consists of a
- ** percent sign - "%" - followed by exactly two hexadecimal digits
- ** specifying an octet value. ^Before the path or query components of a
- ** URI filename are interpreted, they are encoded using UTF-8 and all
- ** hexadecimal escape sequences replaced by a single byte containing the
- ** corresponding octet. If this process generates an invalid UTF-8 encoding,
- ** the results are undefined.
- **
- ** <b>Note to Windows users:</b> The encoding used for the filename argument
- ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
- ** codepage is currently defined. Filenames containing international
- ** characters must be converted to UTF-8 prior to passing them into
- ** sqlite3_open() or sqlite3_open_v2().
- */
- SQLITE_API int sqlite3_open(
- const char *filename, /* Database filename (UTF-8) */
- sqlite3 **ppDb /* OUT: SQLite db handle */
- );
- SQLITE_API int sqlite3_open16(
- const void *filename, /* Database filename (UTF-16) */
- sqlite3 **ppDb /* OUT: SQLite db handle */
- );
- SQLITE_API int sqlite3_open_v2(
- const char *filename, /* Database filename (UTF-8) */
- sqlite3 **ppDb, /* OUT: SQLite db handle */
- int flags, /* Flags */
- const char *zVfs /* Name of VFS module to use */
- );
- /*
- ** CAPI3REF: Obtain Values For URI Parameters
- **
- ** These are utility routines, useful to VFS implementations, that check
- ** to see if a database file was a URI that contained a specific query
- ** parameter, and if so obtains the value of that query parameter.
- **
- ** If F is the database filename pointer passed into the xOpen() method of
- ** a VFS implementation when the flags parameter to xOpen() has one or
- ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
- ** P is the name of the query parameter, then
- ** sqlite3_uri_parameter(F,P) returns the value of the P
- ** parameter if it exists or a NULL pointer if P does not appear as a
- ** query parameter on F. If P is a query parameter of F
- ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
- ** a pointer to an empty string.
- **
- ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
- ** parameter and returns true (1) or false (0) according to the value
- ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
- ** value of query parameter P is one of "yes", "true", or "on" in any
- ** case or if the value begins with a non-zero number. The
- ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
- ** query parameter P is one of "no", "false", or "off" in any case or
- ** if the value begins with a numeric zero. If P is not a query
- ** parameter on F or if the value of P is does not match any of the
- ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
- **
- ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
- ** 64-bit signed integer and returns that integer, or D if P does not
- ** exist. If the value of P is something other than an integer, then
- ** zero is returned.
- **
- ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
- ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
- ** is not a database file pathname pointer that SQLite passed into the xOpen
- ** VFS method, then the behavior of this routine is undefined and probably
- ** undesirable.
- */
- SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
- SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
- SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
- /*
- ** CAPI3REF: Error Codes And Messages
- **
- ** ^The sqlite3_errcode() interface returns the numeric [result code] or
- ** [extended result code] for the most recent failed sqlite3_* API call
- ** associated with a [database connection]. If a prior API call failed
- ** but the most recent API call succeeded, the return value from
- ** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
- ** interface is the same except that it always returns the
- ** [extended result code] even when extended result codes are
- ** disabled.
- **
- ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
- ** text that describes the error, as either UTF-8 or UTF-16 respectively.
- ** ^(Memory to hold the error message string is managed internally.
- ** The application does not need to worry about freeing the result.
- ** However, the error string might be overwritten or deallocated by
- ** subsequent calls to other SQLite interface functions.)^
- **
- ** When the serialized [threading mode] is in use, it might be the
- ** case that a second error occurs on a separate thread in between
- ** the time of the first error and the call to these interfaces.
- ** When that happens, the second error will be reported since these
- ** interfaces always report the most recent result. To avoid
- ** this, each thread can obtain exclusive use of the [database connection] D
- ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
- ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
- ** all calls to the interfaces listed here are completed.
- **
- ** If an interface fails with SQLITE_MISUSE, that means the interface
- ** was invoked incorrectly by the application. In that case, the
- ** error code and message may or may not be set.
- */
- SQLITE_API int sqlite3_errcode(sqlite3 *db);
- SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
- SQLITE_API const char *sqlite3_errmsg(sqlite3*);
- SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
- /*
- ** CAPI3REF: SQL Statement Object
- ** KEYWORDS: {prepared statement} {prepared statements}
- **
- ** An instance of this object represents a single SQL statement.
- ** This object is variously known as a "prepared statement" or a
- ** "compiled SQL statement" or simply as a "statement".
- **
- ** The life of a statement object goes something like this:
- **
- ** <ol>
- ** <li> Create the object using [sqlite3_prepare_v2()] or a related
- ** function.
- ** <li> Bind values to [host parameters] using the sqlite3_bind_*()
- ** interfaces.
- ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
- ** <li> Reset the statement using [sqlite3_reset()] then go back
- ** to step 2. Do this zero or more times.
- ** <li> Destroy the object using [sqlite3_finalize()].
- ** </ol>
- **
- ** Refer to documentation on individual methods above for additional
- ** information.
- */
- typedef struct sqlite3_stmt sqlite3_stmt;
- /*
- ** CAPI3REF: Run-time Limits
- **
- ** ^(This interface allows the size of various constructs to be limited
- ** on a connection by connection basis. The first parameter is the
- ** [database connection] whose limit is to be set or queried. The
- ** second parameter is one of the [limit categories] that define a
- ** class of constructs to be size limited. The third parameter is the
- ** new limit for that construct.)^
- **
- ** ^If the new limit is a negative number, the limit is unchanged.
- ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
- ** [limits | hard upper bound]
- ** set at compile-time by a C preprocessor macro called
- ** [limits | SQLITE_MAX_<i>NAME</i>].
- ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
- ** ^Attempts to increase a limit above its hard upper bound are
- ** silently truncated to the hard upper bound.
- **
- ** ^Regardless of whether or not the limit was changed, the
- ** [sqlite3_limit()] interface returns the prior value of the limit.
- ** ^Hence, to find the current value of a limit without changing it,
- ** simply invoke this interface with the third parameter set to -1.
- **
- ** Run-time limits are intended for use in applications that manage
- ** both their own internal database and also databases that are controlled
- ** by untrusted external sources. An example application might be a
- ** web browser that has its own databases for storing history and
- ** separate databases controlled by JavaScript applications downloaded
- ** off the Internet. The internal databases can be given the
- ** large, default limits. Databases managed by external sources can
- ** be given much smaller limits designed to prevent a denial of service
- ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
- ** interface to further control untrusted SQL. The size of the database
- ** created by an untrusted script can be contained using the
- ** [max_page_count] [PRAGMA].
- **
- ** New run-time limit categories may be added in future releases.
- */
- SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
- /*
- ** CAPI3REF: Run-Time Limit Categories
- ** KEYWORDS: {limit category} {*limit categories}
- **
- ** These constants define various performance limits
- ** that can be lowered at run-time using [sqlite3_limit()].
- ** The synopsis of the meanings of the various limits is shown below.
- ** Additional information is available at [limits | Limits in SQLite].
- **
- ** <dl>
- ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
- ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
- **
- ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
- ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
- **
- ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
- ** <dd>The maximum number of columns in a table definition or in the
- ** result set of a [SELECT] or the maximum number of columns in an index
- ** or in an ORDER BY or GROUP BY clause.</dd>)^
- **
- ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
- ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
- **
- ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
- ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
- **
- ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
- ** <dd>The maximum number of instructions in a virtual machine program
- ** used to implement an SQL statement. This limit is not currently
- ** enforced, though that might be added in some future release of
- ** SQLite.</dd>)^
- **
- ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
- ** <dd>The maximum number of arguments on a function.</dd>)^
- **
- ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
- ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
- **
- ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
- ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
- ** <dd>The maximum length of the pattern argument to the [LIKE] or
- ** [GLOB] operators.</dd>)^
- **
- ** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
- ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
- ** <dd>The maximum index number of any [parameter] in an SQL statement.)^
- **
- ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
- ** <dd>The maximum depth of recursion for triggers.</dd>)^
- ** </dl>
- */
- #define SQLITE_LIMIT_LENGTH 0
- #define SQLITE_LIMIT_SQL_LENGTH 1
- #define SQLITE_LIMIT_COLUMN 2
- #define SQLITE_LIMIT_EXPR_DEPTH 3
- #define SQLITE_LIMIT_COMPOUND_SELECT 4
- #define SQLITE_LIMIT_VDBE_OP 5
- #define SQLITE_LIMIT_FUNCTION_ARG 6
- #define SQLITE_LIMIT_ATTACHED 7
- #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
- #define SQLITE_LIMIT_VARIABLE_NUMBER 9
- #define SQLITE_LIMIT_TRIGGER_DEPTH 10
- /*
- ** CAPI3REF: Compiling An SQL Statement
- ** KEYWORDS: {SQL statement compiler}
- **
- ** To execute an SQL query, it must first be compiled into a byte-code
- ** program using one of these routines.
- **
- ** The first argument, "db", is a [database connection] obtained from a
- ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
- ** [sqlite3_open16()]. The database connection must not have been closed.
- **
- ** The second argument, "zSql", is the statement to be compiled, encoded
- ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
- ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
- ** use UTF-16.
- **
- ** ^If the nByte argument is less than zero, then zSql is read up to the
- ** first zero terminator. ^If nByte is non-negative, then it is the maximum
- ** number of bytes read from zSql. ^When nByte is non-negative, the
- ** zSql string ends at either the first '\000' or '\u0000' character or
- ** the nByte-th byte, whichever comes first. If the caller knows
- ** that the supplied string is nul-terminated, then there is a small
- ** performance advantage to be gained by passing an nByte parameter that
- ** is equal to the number of bytes in the input string <i>including</i>
- ** the nul-terminator bytes as this saves SQLite from having to
- ** make a copy of the input string.
- **
- ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
- ** past the end of the first SQL statement in zSql. These routines only
- ** compile the first statement in zSql, so *pzTail is left pointing to
- ** what remains uncompiled.
- **
- ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
- ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
- ** to NULL. ^If the input text contains no SQL (if the input is an empty
- ** string or a comment) then *ppStmt is set to NULL.
- ** The calling procedure is responsible for deleting the compiled
- ** SQL statement using [sqlite3_finalize()] after it has finished with it.
- ** ppStmt may not be NULL.
- **
- ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
- ** otherwise an [error code] is returned.
- **
- ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
- ** recommended for all new programs. The two older interfaces are retained
- ** for backwards compatibility, but their use is discouraged.
- ** ^In the "v2" interfaces, the prepared statement
- ** that is returned (the [sqlite3_stmt] object) contains a copy of the
- ** original SQL text. This causes the [sqlite3_step()] interface to
- ** behave differently in three ways:
- **
- ** <ol>
- ** <li>
- ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
- ** always used to do, [sqlite3_step()] will automatically recompile the SQL
- ** statement and try to run it again.
- ** </li>
- **
- ** <li>
- ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
- ** [error codes] or [extended error codes]. ^The legacy behavior was that
- ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
- ** and the application would have to make a second call to [sqlite3_reset()]
- ** in order to find the underlying cause of the problem. With the "v2" prepare
- ** interfaces, the underlying reason for the error is returned immediately.
- ** </li>
- **
- ** <li>
- ** ^If the specific value bound to [parameter | host parameter] in the
- ** WHERE clause might influence the choice of query plan for a statement,
- ** then the statement will be automatically recompiled, as if there had been
- ** a schema change, on the first [sqlite3_step()] call following any change
- ** to the [sqlite3_bind_text | bindings] of that [parameter].
- ** ^The specific value of WHERE-clause [parameter] might influence the
- ** choice of query plan if the parameter is the left-hand side of a [LIKE]
- ** or [GLOB] operator or if the parameter is compared to an indexed column
- ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
- ** the
- ** </li>
- ** </ol>
- */
- SQLITE_API int sqlite3_prepare(
- sqlite3 *db, /* Database handle */
- const char *zSql, /* SQL statement, UTF-8 encoded */
- int nByte, /* Maximum length of zSql in bytes. */
- sqlite3_stmt **ppStmt, /* OUT: Statement handle */
- const char **pzTail /* OUT: Pointer to unused portion of zSql */
- );
- SQLITE_API int sqlite3_prepare_v2(
- sqlite3 *db, /* Database handle */
- const char *zSql, /* SQL statement, UTF-8 encoded */
- int nByte, /* Maximum length of zSql in bytes. */
- sqlite3_stmt **ppStmt, /* OUT: Statement handle */
- const char **pzTail /* OUT: Pointer to unused portion of zSql */
- );
- SQLITE_API int sqlite3_prepare16(
- sqlite3 *db, /* Database handle */
- const void *zSql, /* SQL statement, UTF-16 encoded */
- int nByte, /* Maximum length of zSql in bytes. */
- sqlite3_stmt **ppStmt, /* OUT: Statement handle */
- const void **pzTail /* OUT: Pointer to unused portion of zSql */
- );
- SQLITE_API int sqlite3_prepare16_v2(
- sqlite3 *db, /* Database handle */
- const void *zSql, /* SQL statement, UTF-16 encoded */
- int nByte, /* Maximum length of zSql in bytes. */
- sqlite3_stmt **ppStmt, /* OUT: Statement handle */
- const void **pzTail /* OUT: Pointer to unused portion of zSql */
- );
- /*
- ** CAPI3REF: Retrieving Statement SQL
- **
- ** ^This interface can be used to retrieve a saved copy of the original
- ** SQL text used to create a [prepared statement] if that statement was
- ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
- */
- SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
- /*
- ** CAPI3REF: Determine If An SQL Statement Writes The Database
- **
- ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
- ** and only if the [prepared statement] X makes no direct changes to
- ** the content of the database file.
- **
- ** Note that [application-defined SQL functions] or
- ** [virtual tables] might change the database indirectly as a side effect.
- ** ^(For example, if an application defines a function "eval()" that
- ** calls [sqlite3_exec()], then the following SQL statement would
- ** change the database file through side-effects:
- **
- ** <blockquote><pre>
- ** SELECT eval('DELETE FROM t1') FROM t2;
- ** </pre></blockquote>
- **
- ** But because the [SELECT] statement does not change the database file
- ** directly, sqlite3_stmt_readonly() would still return true.)^
- **
- ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
- ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
- ** since the statements themselves do not actually modify the database but
- ** rather they control the timing of when other statements modify the
- ** database. ^The [ATTACH] and [DETACH] statements also cause
- ** sqlite3_stmt_readonly() to return true since, while those statements
- ** change the configuration of a database connection, they do not make
- ** changes to the content of the database files on disk.
- */
- SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
- /*
- ** CAPI3REF: Determine If A Prepared Statement Has Been Reset
- **
- ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
- ** [prepared statement] S has been stepped at least once using
- ** [sqlite3_step(S)] but has not run to completion and/or has not
- ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
- ** interface returns false if S is a NULL pointer. If S is not a
- ** NULL pointer and is not a pointer to a valid [prepared statement]
- ** object, then the behavior is undefined and probably undesirable.
- **
- ** This interface can be used in combination [sqlite3_next_stmt()]
- ** to locate all prepared statements associated with a database
- ** connection that are in need of being reset. This can be used,
- ** for example, in diagnostic routines to search for prepared
- ** statements that are holding a transaction open.
- */
- SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
- /*
- ** CAPI3REF: Dynamically Typed Value Object
- ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
- **
- ** SQLite uses the sqlite3_value object to represent all values
- ** that can be stored in a database table. SQLite uses dynamic typing
- ** for the values it stores. ^Values stored in sqlite3_value objects
- ** can be integers, floating point values, strings, BLOBs, or NULL.
- **
- ** An sqlite3_value object may be either "protected" or "unprotected".
- ** Some interfaces require a protected sqlite3_value. Other interfaces
- ** will accept either a protected or an unprotected sqlite3_value.
- ** Every interface that accepts sqlite3_value arguments specifies
- ** whether or not it requires a protected sqlite3_value.
- **
- ** The terms "protected" and "unprotected" refer to whether or not
- ** a mutex is held. An internal mutex is held for a protected
- ** sqlite3_value object but no mutex is held for an unprotected
- ** sqlite3_value object. If SQLite is compiled to be single-threaded
- ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
- ** or if SQLite is run in one of reduced mutex modes
- ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
- ** then there is no distinction between protected and unprotected
- ** sqlite3_value objects and they can be used interchangeably. However,
- ** for maximum code portability it is recommended that applications
- ** still make the distinction between protected and unprotected
- ** sqlite3_value objects even when not strictly required.
- **
- ** ^The sqlite3_value objects that are passed as parameters into the
- ** implementation of [application-defined SQL functions] are protected.
- ** ^The sqlite3_value object returned by
- ** [sqlite3_column_value()] is unprotected.
- ** Unprotected sqlite3_value objects may only be used with
- ** [sqlite3_result_value()] and [sqlite3_bind_value()].
- ** The [sqlite3_value_blob | sqlite3_value_type()] family of
- ** interfaces require protected sqlite3_value objects.
- */
- typedef struct Mem sqlite3_value;
- /*
- ** CAPI3REF: SQL Function Context Object
- **
- ** The context in which an SQL function executes is stored in an
- ** sqlite3_context object. ^A pointer to an sqlite3_context object
- ** is always first parameter to [application-defined SQL functions].
- ** The application-defined SQL function implementation will pass this
- ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
- ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
- ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
- ** and/or [sqlite3_set_auxdata()].
- */
- typedef struct sqlite3_context sqlite3_context;
- /*
- ** CAPI3REF: Binding Values To Prepared Statements
- ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
- ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
- **
- ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
- ** literals may be replaced by a [parameter] that matches one of following
- ** templates:
- **
- ** <ul>
- ** <li> ?
- ** <li> ?NNN
- ** <li> :VVV
- ** <li> @VVV
- ** <li> $VVV
- ** </ul>
- **
- ** In the templates above, NNN represents an integer literal,
- ** and VVV represents an alphanumeric identifier.)^ ^The values of these
- ** parameters (also called "host parameter names" or "SQL parameters")
- ** can be set using the sqlite3_bind_*() routines defined here.
- **
- ** ^The first argument to the sqlite3_bind_*() routines is always
- ** a pointer to the [sqlite3_stmt] object returned from
- ** [sqlite3_prepare_v2()] or its variants.
- **
- ** ^The second argument is the index of the SQL parameter to be set.
- ** ^The leftmost SQL parameter has an index of 1. ^When the same named
- ** SQL parameter is used more than once, second and subsequent
- ** occurrences have the same index as the first occurrence.
- ** ^The index for named parameters can be looked up using the
- ** [sqlite3_bind_parameter_index()] API if desired. ^The index
- ** for "?NNN" parameters is the value of NNN.
- ** ^The NNN value must be between 1 and the [sqlite3_limit()]
- ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
- **
- ** ^The third argument is the value to bind to the parameter.
- **
- ** ^(In those routines that have a fourth argument, its value is the
- ** number of bytes in the parameter. To be clear: the value is the
- ** number of <u>bytes</u> in the value, not the number of characters.)^
- ** ^If the fourth parameter is negative, the length of the string is
- ** the number of bytes up to the first zero terminator.
- ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
- ** or sqlite3_bind_text16() then that parameter must be the byte offset
- ** where the NUL terminator would occur assuming the string were NUL
- ** terminated. If any NUL characters occur at byte offsets less than
- ** the value of the fourth parameter then the resulting string value will
- ** contain embedded NULs. The result of expressions involving strings
- ** with embedded NULs is undefined.
- **
- ** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
- ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
- ** string after SQLite has finished with it. ^The destructor is called
- ** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
- ** sqlite3_bind_text(), or sqlite3_bind_text16() fails.
- ** ^If the fifth argument is
- ** the special value [SQLITE_STATIC], then SQLite assumes that the
- ** information is in static, unmanaged space and does not need to be freed.
- ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
- ** SQLite makes its own private copy of the data immediately, before
- ** the sqlite3_bind_*() routine returns.
- **
- ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
- ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
- ** (just an integer to hold its size) while it is being processed.
- ** Zeroblobs are intended to serve as placeholders for BLOBs whose
- ** content is later written using
- ** [sqlite3_blob_open | incremental BLOB I/O] routines.
- ** ^A negative value for the zeroblob results in a zero-length BLOB.
- **
- ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
- ** for the [prepared statement] or with a prepared statement for which
- ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
- ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
- ** routine is passed a [prepared statement] that has been finalized, the
- ** result is undefined and probably harmful.
- **
- ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
- ** ^Unbound parameters are interpreted as NULL.
- **
- ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
- ** [error code] if anything goes wrong.
- ** ^[SQLITE_RANGE] is returned if the parameter
- ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
- **
- ** See also: [sqlite3_bind_parameter_count()],
- ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
- */
- SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
- SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
- SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
- SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
- SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
- SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
- SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
- SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
- SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
- /*
- ** CAPI3REF: Number Of SQL Parameters
- **
- ** ^This routine can be used to find the number of [SQL parameters]
- ** in a [prepared statement]. SQL parameters are tokens of the
- ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
- ** placeholders for values that are [sqlite3_bind_blob | bound]
- ** to the parameters at a later time.
- **
- ** ^(This routine actually returns the index of the largest (rightmost)
- ** parameter. For all forms except ?NNN, this will correspond to the
- ** number of unique parameters. If parameters of the ?NNN form are used,
- ** there may be gaps in the list.)^
- **
- ** See also: [sqlite3_bind_blob|sqlite3_bind()],
- ** [sqlite3_bind_parameter_name()], and
- ** [sqlite3_bind_parameter_index()].
- */
- SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
- /*
- ** CAPI3REF: Name Of A Host Parameter
- **
- ** ^The sqlite3_bind_parameter_name(P,N) interface returns
- ** the name of the N-th [SQL parameter] in the [prepared statement] P.
- ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
- ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
- ** respectively.
- ** In other words, the initial ":" or "$" or "@" or "?"
- ** is included as part of the name.)^
- ** ^Parameters of the form "?" without a following integer have no name
- ** and are referred to as "nameless" or "anonymous parameters".
- **
- ** ^The first host parameter has an index of 1, not 0.
- **
- ** ^If the value N is out of range or if the N-th parameter is
- ** nameless, then NULL is returned. ^The returned string is
- ** always in UTF-8 encoding even if the named parameter was
- ** originally specified as UTF-16 in [sqlite3_prepare16()] or
- ** [sqlite3_prepare16_v2()].
- **
- ** See also: [sqlite3_bind_blob|sqlite3_bind()],
- ** [sqlite3_bind_parameter_count()], and
- ** [sqlite3_bind_parameter_index()].
- */
- SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
- /*
- ** CAPI3REF: Index Of A Parameter With A Given Name
- **
- ** ^Return the index of an SQL parameter given its name. ^The
- ** index value returned is suitable for use as the second
- ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
- ** is returned if no matching parameter is found. ^The parameter
- ** name must be given in UTF-8 even if the original statement
- ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
- **
- ** See also: [sqlite3_bind_blob|sqlite3_bind()],
- ** [sqlite3_bind_parameter_count()], and
- ** [sqlite3_bind_parameter_index()].
- */
- SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
- /*
- ** CAPI3REF: Reset All Bindings On A Prepared Statement
- **
- ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
- ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
- ** ^Use this routine to reset all host parameters to NULL.
- */
- SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
- /*
- ** CAPI3REF: Number Of Columns In A Result Set
- **
- ** ^Return the number of columns in the result set returned by the
- ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
- ** statement that does not return data (for example an [UPDATE]).
- **
- ** See also: [sqlite3_data_count()]
- */
- SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
- /*
- ** CAPI3REF: Column Names In A Result Set
- **
- ** ^These routines return the name assigned to a particular column
- ** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
- ** interface returns a pointer to a zero-terminated UTF-8 string
- ** and sqlite3_column_name16() returns a pointer to a zero-terminated
- ** UTF-16 string. ^The first parameter is the [prepared statement]
- ** that implements the [SELECT] statement. ^The second parameter is the
- ** column number. ^The leftmost column is number 0.
- **
- ** ^The returned string pointer is valid until either the [prepared statement]
- ** is destroyed by [sqlite3_finalize()] or until the statement is automatically
- ** reprepared by the first call to [sqlite3_step()] for a particular run
- ** or until the next call to
- ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
- **
- ** ^If sqlite3_malloc() fails during the processing of either routine
- ** (for example during a conversion from UTF-8 to UTF-16) then a
- ** NULL pointer is returned.
- **
- ** ^The name of a result column is the value of the "AS" clause for
- ** that column, if there is an AS clause. If there is no AS clause
- ** then the name of the column is unspecified and may change from
- ** one release of SQLite to the next.
- */
- SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
- SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
- /*
- ** CAPI3REF: Source Of Data In A Query Result
- **
- ** ^These routines provide a means to determine the database, table, and
- ** table column that is the origin of a particular result column in
- ** [SELECT] statement.
- ** ^The name of the database or table or column can be returned as
- ** either a UTF-8 or UTF-16 string. ^The _database_ routines return
- ** the database name, the _table_ routines return the table name, and
- ** the origin_ routines return the column name.
- ** ^The returned string is valid until the [prepared statement] is destroyed
- ** using [sqlite3_finalize()] or until the statement is automatically
- ** reprepared by the first call to [sqlite3_step()] for a particular run
- ** or until the same information is requested
- ** again in a different encoding.
- **
- ** ^The names returned are the original un-aliased names of the
- ** database, table, and column.
- **
- ** ^The first argument to these interfaces is a [prepared statement].
- ** ^These functions return information about the Nth result column returned by
- ** the statement, where N is the second function argument.
- ** ^The left-most column is column 0 for these routines.
- **
- ** ^If the Nth column returned by the statement is an expression or
- ** subquery and is not a column value, then all of these functions return
- ** NULL. ^These routine might also return NULL if a memory allocation error
- ** occurs. ^Otherwise, they return the name of the attached database, table,
- ** or column that query result column was extracted from.
- **
- ** ^As with all other SQLite APIs, those whose names end with "16" return
- ** UTF-16 encoded strings and the other functions return UTF-8.
- **
- ** ^These APIs are only available if the library was compiled with the
- ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
- **
- ** If two or more threads call one or more of these routines against the same
- ** prepared statement and column at the same time then the results are
- ** undefined.
- **
- ** If two or more threads call one or more
- ** [sqlite3_column_database_name | column metadata interfaces]
- ** for the same [prepared statement] and result column
- ** at the same time then the results are undefined.
- */
- SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
- SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
- SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
- SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
- SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
- SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
- /*
- ** CAPI3REF: Declared Datatype Of A Query Result
- **
- ** ^(The first parameter is a [prepared statement].
- ** If this statement is a [SELECT] statement and the Nth column of the
- ** returned result set of that [SELECT] is a table column (not an
- ** expression or subquery) then the declared type of the table
- ** column is returned.)^ ^If the Nth column of the result set is an
- ** expression or subquery, then a NULL pointer is returned.
- ** ^The returned string is always UTF-8 encoded.
- **
- ** ^(For example, given the database schema:
- **
- ** CREATE TABLE t1(c1 VARIANT);
- **
- ** and the following statement to be compiled:
- **
- ** SELECT c1 + 1, c1 FROM t1;
- **
- ** this routine would return the string "VARIANT" for the second result
- ** column (i==1), and a NULL pointer for the first result column (i==0).)^
- **
- ** ^SQLite uses dynamic run-time typing. ^So just because a column
- ** is declared to contain a particular type does not mean that the
- ** data stored in that column is of the declared type. SQLite is
- ** strongly typed, but the typing is dynamic not static. ^Type
- ** is associated with individual values, not with the containers
- ** used to hold those values.
- */
- SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
- SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
- /*
- ** CAPI3REF: Evaluate An SQL Statement
- **
- ** After a [prepared statement] has been prepared using either
- ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
- ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
- ** must be called one or more times to evaluate the statement.
- **
- ** The details of the behavior of the sqlite3_step() interface depend
- ** on whether the statement was prepared using the newer "v2" interface
- ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
- ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
- ** new "v2" interface is recommended for new applications but the legacy
- ** interface will continue to be supported.
- **
- ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
- ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
- ** ^With the "v2" interface, any of the other [result codes] or
- ** [extended result codes] might be returned as well.
- **
- ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
- ** database locks it needs to do its job. ^If the statement is a [COMMIT]
- ** or occurs outside of an explicit transaction, then you can retry the
- ** statement. If the statement is not a [COMMIT] and occurs within an
- ** explicit transaction then you should rollback the transaction before
- ** continuing.
- **
- ** ^[SQLITE_DONE] means that the statement has finished executing
- ** successfully. sqlite3_step() should not be called again on this virtual
- ** machine without first calling [sqlite3_reset()] to reset the virtual
- ** machine back to its initial state.
- **
- ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
- ** is returned each time a new row of data is ready for processing by the
- ** caller. The values may be accessed using the [column access functions].
- ** sqlite3_step() is called again to retrieve the next row of data.
- **
- ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
- ** violation) has occurred. sqlite3_step() should not be called again on
- ** the VM. More information may be found by calling [sqlite3_errmsg()].
- ** ^With the legacy interface, a more specific error code (for example,
- ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
- ** can be obtained by calling [sqlite3_reset()] on the
- ** [prepared statement]. ^In the "v2" interface,
- ** the more specific error code is returned directly by sqlite3_step().
- **
- ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
- ** Perhaps it was called on a [prepared statement] that has
- ** already been [sqlite3_finalize | finalized] or on one that had
- ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
- ** be the case that the same database connection is being used by two or
- ** more threads at the same moment in time.
- **
- ** For all versions of SQLite up to and including 3.6.23.1, a call to
- ** [sqlite3_reset()] was required after sqlite3_step() returned anything
- ** other than [SQLITE_ROW] before any subsequent invocation of
- ** sqlite3_step(). Failure to reset the prepared statement using
- ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
- ** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began
- ** calling [sqlite3_reset()] automatically in this circumstance rather
- ** than returning [SQLITE_MISUSE]. This is not considered a compatibility
- ** break because any application that ever receives an SQLITE_MISUSE error
- ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
- ** can be used to restore the legacy behavior.
- **
- ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
- ** API always returns a generic error code, [SQLITE_ERROR], following any
- ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
- ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
- ** specific [error codes] that better describes the error.
- ** We admit that this is a goofy design. The problem has been fixed
- ** with the "v2" interface. If you prepare all of your SQL statements
- ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
- ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
- ** then the more specific [error codes] are returned directly
- ** by sqlite3_step(). The use of the "v2" interface is recommended.
- */
- SQLITE_API int sqlite3_step(sqlite3_stmt*);
- /*
- ** CAPI3REF: Number of columns in a result set
- **
- ** ^The sqlite3_data_count(P) interface returns the number of columns in the
- ** current row of the result set of [prepared statement] P.
- ** ^If prepared statement P does not have results ready to return
- ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
- ** interfaces) then sqlite3_data_count(P) returns 0.
- ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
- ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
- ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
- ** will return non-zero if previous call to [sqlite3_step](P) returned
- ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
- ** where it always returns zero since each step of that multi-step
- ** pragma returns 0 columns of data.
- **
- ** See also: [sqlite3_column_count()]
- */
- SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
- /*
- ** CAPI3REF: Fundamental Datatypes
- ** KEYWORDS: SQLITE_TEXT
- **
- ** ^(Every value in SQLite has one of five fundamental datatypes:
- **
- ** <ul>
- ** <li> 64-bit signed integer
- ** <li> 64-bit IEEE floating point number
- ** <li> string
- ** <li> BLOB
- ** <li> NULL
- ** </ul>)^
- **
- ** These constants are codes for each of those types.
- **
- ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
- ** for a completely different meaning. Software that links against both
- ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
- ** SQLITE_TEXT.
- */
- #define SQLITE_INTEGER 1
- #define SQLITE_FLOAT 2
- #define SQLITE_BLOB 4
- #define SQLITE_NULL 5
- #ifdef SQLITE_TEXT
- # undef SQLITE_TEXT
- #else
- # define SQLITE_TEXT 3
- #endif
- #define SQLITE3_TEXT 3
- /*
- ** CAPI3REF: Result Values From A Query
- ** KEYWORDS: {column access functions}
- **
- ** These routines form the "result set" interface.
- **
- ** ^These routines return information about a single column of the current
- ** result row of a query. ^In every case the first argument is a pointer
- ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
- ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
- ** and the second argument is the index of the column for which information
- ** should be returned. ^The leftmost column of the result set has the index 0.
- ** ^The number of columns in the result can be determined using
- ** [sqlite3_column_count()].
- **
- ** If the SQL statement does not currently point to a valid row, or if the
- ** column index is out of range, the result is undefined.
- ** These routines may only be called when the most recent call to
- ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
- ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
- ** If any of these routines are called after [sqlite3_reset()] or
- ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
- ** something other than [SQLITE_ROW], the results are undefined.
- ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
- ** are called from a different thread while any of these routines
- ** are pending, then the results are undefined.
- **
- ** ^The sqlite3_column_type() routine returns the
- ** [SQLITE_INTEGER | datatype code] for the initial data type
- ** of the result column. ^The returned value is one of [SQLITE_INTEGER],
- ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
- ** returned by sqlite3_column_type() is only meaningful if no type
- ** conversions have occurred as described below. After a type conversion,
- ** the value returned by sqlite3_column_type() is undefined. Future
- ** versions of SQLite may change the behavior of sqlite3_column_type()
- ** following a type conversion.
- **
- ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
- ** routine returns the number of bytes in that BLOB or string.
- ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
- ** the string to UTF-8 and then returns the number of bytes.
- ** ^If the result is a numeric value then sqlite3_column_bytes() uses
- ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
- ** the number of bytes in that string.
- ** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
- **
- ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
- ** routine returns the number of bytes in that BLOB or string.
- ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
- ** the string to UTF-16 and then returns the number of bytes.
- ** ^If the result is a numeric value then sqlite3_column_bytes16() uses
- ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
- ** the number of bytes in that string.
- ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
- **
- ** ^The values returned by [sqlite3_column_bytes()] and
- ** [sqlite3_column_bytes16()] do not include the zero terminators at the end
- ** of the string. ^For clarity: the values returned by
- ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
- ** bytes in the string, not the number of characters.
- **
- ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
- ** even empty strings, are always zero-terminated. ^The return
- ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
- **
- ** ^The object returned by [sqlite3_column_value()] is an
- ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
- ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
- ** If the [unprotected sqlite3_value] object returned by
- ** [sqlite3_column_value()] is used in any other way, including calls
- ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
- ** or [sqlite3_value_bytes()], then the behavior is undefined.
- **
- ** These routines attempt to convert the value where appropriate. ^For
- ** example, if the internal representation is FLOAT and a text result
- ** is requested, [sqlite3_snprintf()] is used internally to perform the
- ** conversion automatically. ^(The following table details the conversions
- ** that are applied:
- **
- ** <blockquote>
- ** <table border="1">
- ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
- **
- ** <tr><td> NULL <td> INTEGER <td> Result is 0
- ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
- ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
- ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
- ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
- ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
- ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
- ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
- ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
- ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
- ** <tr><td> TEXT <td> INTEGER <td> Use atoi()
- ** <tr><td> TEXT <td> FLOAT <td> Use atof()
- ** <tr><td> TEXT <td> BLOB <td> No change
- ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
- ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
- ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
- ** </table>
- ** </blockquote>)^
- **
- ** The table above makes reference to standard C library functions atoi()
- ** and atof(). SQLite does not really use these functions. It has its
- ** own equivalent internal routines. The atoi() and atof() names are
- ** used in the table for brevity and because they are familiar to most
- ** C programmers.
- **
- ** Note that when type conversions occur, pointers returned by prior
- ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
- ** sqlite3_column_text16() may be invalidated.
- ** Type conversions and pointer invalidations might occur
- ** in the following cases:
- **
- ** <ul>
- ** <li> The initial content is a BLOB and sqlite3_column_text() or
- ** sqlite3_column_text16() is called. A zero-terminator might
- ** need to be added to the string.</li>
- ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
- ** sqlite3_column_text16() is called. The content must be converted
- ** to UTF-16.</li>
- ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
- ** sqlite3_column_text() is called. The content must be converted
- ** to UTF-8.</li>
- ** </ul>
- **
- ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
- ** not invalidate a prior pointer, though of course the content of the buffer
- ** that the prior pointer references will have been modified. Other kinds
- ** of conversion are done in place when it is possible, but sometimes they
- ** are not possible and in those cases prior pointers are invalidated.
- **
- ** The safest and easiest to remember policy is to invoke these routines
- ** in one of the following ways:
- **
- ** <ul>
- ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
- ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
- ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
- ** </ul>
- **
- ** In other words, you should call sqlite3_column_text(),
- ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
- ** into the desired format, then invoke sqlite3_column_bytes() or
- ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
- ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
- ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
- ** with calls to sqlite3_column_bytes().
- **
- ** ^The pointers returned are valid until a type conversion occurs as
- ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
- ** [sqlite3_finalize()] is called. ^The memory space used to hold strings
- ** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
- ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
- ** [sqlite3_free()].
- **
- ** ^(If a memory allocation error occurs during the evaluation of any
- ** of these routines, a default value is returned. The default value
- ** is either the integer 0, the floating point number 0.0, or a NULL
- ** pointer. Subsequent calls to [sqlite3_errcode()] will return
- ** [SQLITE_NOMEM].)^
- */
- SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
- SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
- SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
- SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
- SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
- SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
- SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
- SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
- SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
- SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
- /*
- ** CAPI3REF: Destroy A Prepared Statement Object
- **
- ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
- ** ^If the most recent evaluation of the statement encountered no errors
- ** or if the statement is never been evaluated, then sqlite3_finalize() returns
- ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
- ** sqlite3_finalize(S) returns the appropriate [error code] or
- ** [extended error code].
- **
- ** ^The sqlite3_finalize(S) routine can be called at any point during
- ** the life cycle of [prepared statement] S:
- ** before statement S is ever evaluated, after
- ** one or more calls to [sqlite3_reset()], or after any call
- ** to [sqlite3_step()] regardless of whether or not the statement has
- ** completed execution.
- **
- ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
- **
- ** The application must finalize every [prepared statement] in order to avoid
- ** resource leaks. It is a grievous error for the application to try to use
- ** a prepared statement after it has been finalized. Any use of a prepared
- ** statement after it has been finalized can result in undefined and
- ** undesirable behavior such as segfaults and heap corruption.
- */
- SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
- /*
- ** CAPI3REF: Reset A Prepared Statement Object
- **
- ** The sqlite3_reset() function is called to reset a [prepared statement]
- ** object back to its initial state, ready to be re-executed.
- ** ^Any SQL statement variables that had values bound to them using
- ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
- ** Use [sqlite3_clear_bindings()] to reset the bindings.
- **
- ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
- ** back to the beginning of its program.
- **
- ** ^If the most recent call to [sqlite3_step(S)] for the
- ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
- ** or if [sqlite3_step(S)] has never before been called on S,
- ** then [sqlite3_reset(S)] returns [SQLITE_OK].
- **
- ** ^If the most recent call to [sqlite3_step(S)] for the
- ** [prepared statement] S indicated an error, then
- ** [sqlite3_reset(S)] returns an appropriate [error code].
- **
- ** ^The [sqlite3_reset(S)] interface does not change the values
- ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
- */
- SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
- /*
- ** CAPI3REF: Create Or Redefine SQL Functions
- ** KEYWORDS: {function creation routines}
- ** KEYWORDS: {application-defined SQL function}
- ** KEYWORDS: {application-defined SQL functions}
- **
- ** ^These functions (collectively known as "function creation routines")
- ** are used to add SQL functions or aggregates or to redefine the behavior
- ** of existing SQL functions or aggregates. The only differences between
- ** these routines are the text encoding expected for
- ** the second parameter (the name of the function being created)
- ** and the presence or absence of a destructor callback for
- ** the application data pointer.
- **
- ** ^The first parameter is the [database connection] to which the SQL
- ** function is to be added. ^If an application uses more than one database
- ** connection then application-defined SQL functions must be added
- ** to each database connection separately.
- **
- ** ^The second parameter is the name of the SQL function to be created or
- ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
- ** representation, exclusive of the zero-terminator. ^Note that the name
- ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
- ** ^Any attempt to create a function with a longer name
- ** will result in [SQLITE_MISUSE] being returned.
- **
- ** ^The third parameter (nArg)
- ** is the number of arguments that the SQL function or
- ** aggregate takes. ^If this parameter is -1, then the SQL function or
- ** aggregate may take any number of arguments between 0 and the limit
- ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
- ** parameter is less than -1 or greater than 127 then the behavior is
- ** undefined.
- **
- ** ^The fourth parameter, eTextRep, specifies what
- ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
- ** its parameters. Every SQL function implementation must be able to work
- ** with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
- ** more efficient with one encoding than another. ^An application may
- ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
- ** times with the same function but with different values of eTextRep.
- ** ^When multiple implementations of the same function are available, SQLite
- ** will pick the one that involves the least amount of data conversion.
- ** If there is only a single implementation which does not care what text
- ** encoding is used, then the fourth argument should be [SQLITE_ANY].
- **
- ** ^(The fifth parameter is an arbitrary pointer. The implementation of the
- ** function can gain access to this pointer using [sqlite3_user_data()].)^
- **
- ** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
- ** pointers to C-language functions that implement the SQL function or
- ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
- ** callback only; NULL pointers must be passed as the xStep and xFinal
- ** parameters. ^An aggregate SQL function requires an implementation of xStep
- ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
- ** SQL function or aggregate, pass NULL pointers for all three function
- ** callbacks.
- **
- ** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
- ** then it is destructor for the application data pointer.
- ** The destructor is invoked when the function is deleted, either by being
- ** overloaded or when the database connection closes.)^
- ** ^The destructor is also invoked if the call to
- ** sqlite3_create_function_v2() fails.
- ** ^When the destructor callback of the tenth parameter is invoked, it
- ** is passed a single argument which is a copy of the application data
- ** pointer which was the fifth parameter to sqlite3_create_function_v2().
- **
- ** ^It is permitted to register multiple implementations of the same
- ** functions with the same name but with either differing numbers of
- ** arguments or differing preferred text encodings. ^SQLite will use
- ** the implementation that most closely matches the way in which the
- ** SQL function is used. ^A function implementation with a non-negative
- ** nArg parameter is a better match than a function implementation with
- ** a negative nArg. ^A function where the preferred text encoding
- ** matches the database encoding is a better
- ** match than a function where the encoding is different.
- ** ^A function where the encoding difference is between UTF16le and UTF16be
- ** is a closer match than a function where the encoding difference is
- ** between UTF8 and UTF16.
- **
- ** ^Built-in functions may be overloaded by new application-defined functions.
- **
- ** ^An application-defined function is permitted to call other
- ** SQLite interfaces. However, such calls must not
- ** close the database connection nor finalize or reset the prepared
- ** statement in which the function is running.
- */
- SQLITE_API int sqlite3_create_function(
- sqlite3 *db,
- const char *zFunctionName,
- int nArg,
- int eTextRep,
- void *pApp,
- void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
- void (*xStep)(sqlite3_context*,int,sqlite3_value**),
- void (*xFinal)(sqlite3_context*)
- );
- SQLITE_API int sqlite3_create_function16(
- sqlite3 *db,
- const void *zFunctionName,
- int nArg,
- int eTextRep,
- void *pApp,
- void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
- void (*xStep)(sqlite3_context*,int,sqlite3_value**),
- void (*xFinal)(sqlite3_context*)
- );
- SQLITE_API int sqlite3_create_function_v2(
- sqlite3 *db,
- const char *zFunctionName,
- int nArg,
- int eTextRep,
- void *pApp,
- void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
- void (*xStep)(sqlite3_context*,int,sqlite3_value**),
- void (*xFinal)(sqlite3_context*),
- void(*xDestroy)(void*)
- );
- /*
- ** CAPI3REF: Text Encodings
- **
- ** These constant define integer codes that represent the various
- ** text encodings supported by SQLite.
- */
- #define SQLITE_UTF8 1
- #define SQLITE_UTF16LE 2
- #define SQLITE_UTF16BE 3
- #define SQLITE_UTF16 4 /* Use native byte order */
- #define SQLITE_ANY 5 /* sqlite3_create_function only */
- #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
- /*
- ** CAPI3REF: Deprecated Functions
- ** DEPRECATED
- **
- ** These functions are [deprecated]. In order to maintain
- ** backwards compatibility with older code, these functions continue
- ** to be supported. However, new applications should avoid
- ** the use of these functions. To help encourage people to avoid
- ** using these functions, we are not going to tell you what they do.
- */
- #ifndef SQLITE_OMIT_DEPRECATED
- SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
- SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
- SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
- SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
- SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
- SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
- #endif
- /*
- ** CAPI3REF: Obtaining SQL Function Parameter Values
- **
- ** The C-language implementation of SQL functions and aggregates uses
- ** this set of interface routines to access the parameter values on
- ** the function or aggregate.
- **
- ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
- ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
- ** define callbacks that implement the SQL functions and aggregates.
- ** The 3rd parameter to these callbacks is an array of pointers to
- ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
- ** each parameter to the SQL function. These routines are used to
- ** extract values from the [sqlite3_value] objects.
- **
- ** These routines work only with [protected sqlite3_value] objects.
- ** Any attempt to use these routines on an [unprotected sqlite3_value]
- ** object results in undefined behavior.
- **
- ** ^These routines work just like the corresponding [column access functions]
- ** except that these routines take a single [protected sqlite3_value] object
- ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
- **
- ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
- ** in the native byte-order of the host machine. ^The
- ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
- ** extract UTF-16 strings as big-endian and little-endian respectively.
- **
- ** ^(The sqlite3_value_numeric_type() interface attempts to apply
- ** numeric affinity to the value. This means that an attempt is
- ** made to convert the value to an integer or floating point. If
- ** such a conversion is possible without loss of information (in other
- ** words, if the value is a string that looks like a number)
- ** then the conversion is performed. Otherwise no conversion occurs.
- ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
- **
- ** Please pay particular attention to the fact that the pointer returned
- ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
- ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
- ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
- ** or [sqlite3_value_text16()].
- **
- ** These routines must be called from the same thread as
- ** the SQL function that supplied the [sqlite3_value*] parameters.
- */
- SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
- SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
- SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
- SQLITE_API double sqlite3_value_double(sqlite3_value*);
- SQLITE_API int sqlite3_value_int(sqlite3_value*);
- SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
- SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
- SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
- SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
- SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
- SQLITE_API int sqlite3_value_type(sqlite3_value*);
- SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
- /*
- ** CAPI3REF: Obtain Aggregate Function Context
- **
- ** Implementations of aggregate SQL functions use this
- ** routine to allocate memory for storing their state.
- **
- ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
- ** for a particular aggregate function, SQLite
- ** allocates N of memory, zeroes out that memory, and returns a pointer
- ** to the new memory. ^On second and subsequent calls to
- ** sqlite3_aggregate_context() for the same aggregate function instance,
- ** the same buffer is returned. Sqlite3_aggregate_context() is normally
- ** called once for each invocation of the xStep callback and then one
- ** last time when the xFinal callback is invoked. ^(When no rows match
- ** an aggregate query, the xStep() callback of the aggregate function
- ** implementation is never called and xFinal() is called exactly once.
- ** In those cases, sqlite3_aggregate_context() might be called for the
- ** first time from within xFinal().)^
- **
- ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
- ** less than or equal to zero or if a memory allocate error occurs.
- **
- ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
- ** determined by the N parameter on first successful call. Changing the
- ** value of N in subsequent call to sqlite3_aggregate_context() within
- ** the same aggregate function instance will not resize the memory
- ** allocation.)^
- **
- ** ^SQLite automatically frees the memory allocated by
- ** sqlite3_aggregate_context() when the aggregate query concludes.
- **
- ** The first parameter must be a copy of the
- ** [sqlite3_context | SQL function context] that is the first parameter
- ** to the xStep or xFinal callback routine that implements the aggregate
- ** function.
- **
- ** This routine must be called from the same thread in which
- ** the aggregate SQL function is running.
- */
- SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
- /*
- ** CAPI3REF: User Data For Functions
- **
- ** ^The sqlite3_user_data() interface returns a copy of
- ** the pointer that was the pUserData parameter (the 5th parameter)
- ** of the [sqlite3_create_function()]
- ** and [sqlite3_create_function16()] routines that originally
- ** registered the application defined function.
- **
- ** This routine must be called from the same thread in which
- ** the application-defined function is running.
- */
- SQLITE_API void *sqlite3_user_data(sqlite3_context*);
- /*
- ** CAPI3REF: Database Connection For Functions
- **
- ** ^The sqlite3_context_db_handle() interface returns a copy of
- ** the pointer to the [database connection] (the 1st parameter)
- ** of the [sqlite3_create_function()]
- ** and [sqlite3_create_function16()] routines that originally
- ** registered the application defined function.
- */
- SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
- /*
- ** CAPI3REF: Function Auxiliary Data
- **
- ** The following two functions may be used by scalar SQL functions to
- ** associate metadata with argument values. If the same value is passed to
- ** multiple invocations of the same SQL function during query execution, under
- ** some circumstances the associated metadata may be preserved. This may
- ** be used, for example, to add a regular-expression matching scalar
- ** function. The compiled version of the regular expression is stored as
- ** metadata associated with the SQL value passed as the regular expression
- ** pattern. The compiled regular expression can be reused on multiple
- ** invocations of the same function so that the original pattern string
- ** does not need to be recompiled on each invocation.
- **
- ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
- ** associated by the sqlite3_set_auxdata() function with the Nth argument
- ** value to the application-defined function. ^If no metadata has been ever
- ** been set for the Nth argument of the function, or if the corresponding
- ** function parameter has changed since the meta-data was set,
- ** then sqlite3_get_auxdata() returns a NULL pointer.
- **
- ** ^The sqlite3_set_auxdata() interface saves the metadata
- ** pointed to by its 3rd parameter as the metadata for the N-th
- ** argument of the application-defined function. Subsequent
- ** calls to sqlite3_get_auxdata() might return this data, if it has
- ** not been destroyed.
- ** ^If it is not NULL, SQLite will invoke the destructor
- ** function given by the 4th parameter to sqlite3_set_auxdata() on
- ** the metadata when the corresponding function parameter changes
- ** or when the SQL statement completes, whichever comes first.
- **
- ** SQLite is free to call the destructor and drop metadata on any
- ** parameter of any function at any time. ^The only guarantee is that
- ** the destructor will be called before the metadata is dropped.
- **
- ** ^(In practice, metadata is preserved between function calls for
- ** expressions that are constant at compile time. This includes literal
- ** values and [parameters].)^
- **
- ** These routines must be called from the same thread in which
- ** the SQL function is running.
- */
- SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
- SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
- /*
- ** CAPI3REF: Constants Defining Special Destructor Behavior
- **
- ** These are special values for the destructor that is passed in as the
- ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
- ** argument is SQLITE_STATIC, it means that the content pointer is constant
- ** and will never change. It does not need to be destroyed. ^The
- ** SQLITE_TRANSIENT value means that the content will likely change in
- ** the near future and that SQLite should make its own private copy of
- ** the content before returning.
- **
- ** The typedef is necessary to work around problems in certain
- ** C++ compilers. See ticket #2191.
- */
- typedef void (*sqlite3_destructor_type)(void*);
- #define SQLITE_STATIC ((sqlite3_destructor_type)0)
- #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
- /*
- ** CAPI3REF: Setting The Result Of An SQL Function
- **
- ** These routines are used by the xFunc or xFinal callbacks that
- ** implement SQL functions and aggregates. See
- ** [sqlite3_create_function()] and [sqlite3_create_function16()]
- ** for additional information.
- **
- ** These functions work very much like the [parameter binding] family of
- ** functions used to bind values to host parameters in prepared statements.
- ** Refer to the [SQL parameter] documentation for additional information.
- **
- ** ^The sqlite3_result_blob() interface sets the result from
- ** an application-defined function to be the BLOB whose content is pointed
- ** to by the second parameter and which is N bytes long where N is the
- ** third parameter.
- **
- ** ^The sqlite3_result_zeroblob() interfaces set the result of
- ** the application-defined function to be a BLOB containing all zero
- ** bytes and N bytes in size, where N is the value of the 2nd parameter.
- **
- ** ^The sqlite3_result_double() interface sets the result from
- ** an application-defined function to be a floating point value specified
- ** by its 2nd argument.
- **
- ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
- ** cause the implemented SQL function to throw an exception.
- ** ^SQLite uses the string pointed to by the
- ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
- ** as the text of an error message. ^SQLite interprets the error
- ** message string from sqlite3_result_error() as UTF-8. ^SQLite
- ** interprets the string from sqlite3_result_error16() as UTF-16 in native
- ** byte order. ^If the third parameter to sqlite3_result_error()
- ** or sqlite3_result_error16() is negative then SQLite takes as the error
- ** message all text up through the first zero character.
- ** ^If the third parameter to sqlite3_result_error() or
- ** sqlite3_result_error16() is non-negative then SQLite takes that many
- ** bytes (not characters) from the 2nd parameter as the error message.
- ** ^The sqlite3_result_error() and sqlite3_result_error16()
- ** routines make a private copy of the error message text before
- ** they return. Hence, the calling function can deallocate or
- ** modify the text after they return without harm.
- ** ^The sqlite3_result_error_code() function changes the error code
- ** returned by SQLite as a result of an error in a function. ^By default,
- ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
- ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
- **
- ** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
- ** indicating that a string or BLOB is too long to represent.
- **
- ** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
- ** indicating that a memory allocation failed.
- **
- ** ^The sqlite3_result_int() interface sets the return value
- ** of the application-defined function to be the 32-bit signed integer
- ** value given in the 2nd argument.
- ** ^The sqlite3_result_int64() interface sets the return value
- ** of the application-defined function to be the 64-bit signed integer
- ** value given in the 2nd argument.
- **
- ** ^The sqlite3_result_null() interface sets the return value
- ** of the application-defined function to be NULL.
- **
- ** ^The sqlite3_result_text(), sqlite3_result_text16(),
- ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
- ** set the return value of the application-defined function to be
- ** a text string which is represented as UTF-8, UTF-16 native byte order,
- ** UTF-16 little endian, or UTF-16 big endian, respectively.
- ** ^SQLite takes the text result from the application from
- ** the 2nd parameter of the sqlite3_result_text* interfaces.
- ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
- ** is negative, then SQLite takes result text from the 2nd parameter
- ** through the first zero character.
- ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
- ** is non-negative, then as many bytes (not characters) of the text
- ** pointed to by the 2nd parameter are taken as the application-defined
- ** function result. If the 3rd parameter is non-negative, then it
- ** must be the byte offset into the string where the NUL terminator would
- ** appear if the string where NUL terminated. If any NUL characters occur
- ** in the string at a byte offset that is less than the value of the 3rd
- ** parameter, then the resulting string will contain embedded NULs and the
- ** result of expressions operating on strings with embedded NULs is undefined.
- ** ^If the 4th parameter to the sqlite3_result_text* interfaces
- ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
- ** function as the destructor on the text or BLOB result when it has
- ** finished using that result.
- ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
- ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
- ** assumes that the text or BLOB result is in constant space and does not
- ** copy the content of the parameter nor call a destructor on the content
- ** when it has finished using that result.
- ** ^If the 4th parameter to the sqlite3_result_text* interfaces
- ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
- ** then SQLite makes a copy of the result into space obtained from
- ** from [sqlite3_malloc()] before it returns.
- **
- ** ^The sqlite3_result_value() interface sets the result of
- ** the application-defined function to be a copy the
- ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
- ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
- ** so that the [sqlite3_value] specified in the parameter may change or
- ** be deallocated after sqlite3_result_value() returns without harm.
- ** ^A [protected sqlite3_value] object may always be used where an
- ** [unprotected sqlite3_value] object is required, so either
- ** kind of [sqlite3_value] object can be used with this interface.
- **
- ** If these routines are called from within the different thread
- ** than the one containing the application-defined function that received
- ** the [sqlite3_context] pointer, the results are undefined.
- */
- SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
- SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
- SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
- SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
- SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
- SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
- SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
- SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
- SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
- SQLITE_API void sqlite3_result_null(sqlite3_context*);
- SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
- SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
- SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
- SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
- SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
- SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
- /*
- ** CAPI3REF: Define New Collating Sequences
- **
- ** ^These functions add, remove, or modify a [collation] associated
- ** with the [database connection] specified as the first argument.
- **
- ** ^The name of the collation is a UTF-8 string
- ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
- ** and a UTF-16 string in native byte order for sqlite3_create_collation16().
- ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
- ** considered to be the same name.
- **
- ** ^(The third argument (eTextRep) must be one of the constants:
- ** <ul>
- ** <li> [SQLITE_UTF8],
- ** <li> [SQLITE_UTF16LE],
- ** <li> [SQLITE_UTF16BE],
- ** <li> [SQLITE_UTF16], or
- ** <li> [SQLITE_UTF16_ALIGNED].
- ** </ul>)^
- ** ^The eTextRep argument determines the encoding of strings passed
- ** to the collating function callback, xCallback.
- ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
- ** force strings to be UTF16 with native byte order.
- ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
- ** on an even byte address.
- **
- ** ^The fourth argument, pArg, is an application data pointer that is passed
- ** through as the first argument to the collating function callback.
- **
- ** ^The fifth argument, xCallback, is a pointer to the collating function.
- ** ^Multiple collating functions can be registered using the same name but
- ** with different eTextRep parameters and SQLite will use whichever
- ** function requires the least amount of data transformation.
- ** ^If the xCallback argument is NULL then the collating function is
- ** deleted. ^When all collating functions having the same name are deleted,
- ** that collation is no longer usable.
- **
- ** ^The collating function callback is invoked with a copy of the pArg
- ** application data pointer and with two strings in the encoding specified
- ** by the eTextRep argument. The collating function must return an
- ** integer that is negative, zero, or positive
- ** if the first string is less than, equal to, or greater than the second,
- ** respectively. A collating function must always return the same answer
- ** given the same inputs. If two or more collating functions are registered
- ** to the same collation name (using different eTextRep values) then all
- ** must give an equivalent answer when invoked with equivalent strings.
- ** The collating function must obey the following properties for all
- ** strings A, B, and C:
- **
- ** <ol>
- ** <li> If A==B then B==A.
- ** <li> If A==B and B==C then A==C.
- ** <li> If A<B THEN B>A.
- ** <li> If A<B and B<C then A<C.
- ** </ol>
- **
- ** If a collating function fails any of the above constraints and that
- ** collating function is registered and used, then the behavior of SQLite
- ** is undefined.
- **
- ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
- ** with the addition that the xDestroy callback is invoked on pArg when
- ** the collating function is deleted.
- ** ^Collating functions are deleted when they are overridden by later
- ** calls to the collation creation functions or when the
- ** [database connection] is closed using [sqlite3_close()].
- **
- ** ^The xDestroy callback is <u>not</u> called if the
- ** sqlite3_create_collation_v2() function fails. Applications that invoke
- ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
- ** check the return code and dispose of the application data pointer
- ** themselves rather than expecting SQLite to deal with it for them.
- ** This is different from every other SQLite interface. The inconsistency
- ** is unfortunate but cannot be changed without breaking backwards
- ** compatibility.
- **
- ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
- */
- SQLITE_API int sqlite3_create_collation(
- sqlite3*,
- const char *zName,
- int eTextRep,
- void *pArg,
- int(*xCompare)(void*,int,const void*,int,const void*)
- );
- SQLITE_API int sqlite3_create_collation_v2(
- sqlite3*,
- const char *zName,
- int eTextRep,
- void *pArg,
- int(*xCompare)(void*,int,const void*,int,const void*),
- void(*xDestroy)(void*)
- );
- SQLITE_API int sqlite3_create_collation16(
- sqlite3*,
- const void *zName,
- int eTextRep,
- void *pArg,
- int(*xCompare)(void*,int,const void*,int,const void*)
- );
- /*
- ** CAPI3REF: Collation Needed Callbacks
- **
- ** ^To avoid having to register all collation sequences before a database
- ** can be used, a single callback function may be registered with the
- ** [database connection] to be invoked whenever an undefined collation
- ** sequence is required.
- **
- ** ^If the function is registered using the sqlite3_collation_needed() API,
- ** then it is passed the names of undefined collation sequences as strings
- ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
- ** the names are passed as UTF-16 in machine native byte order.
- ** ^A call to either function replaces the existing collation-needed callback.
- **
- ** ^(When the callback is invoked, the first argument passed is a copy
- ** of the second argument to sqlite3_collation_needed() or
- ** sqlite3_collation_needed16(). The second argument is the database
- ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
- ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
- ** sequence function required. The fourth parameter is the name of the
- ** required collation sequence.)^
- **
- ** The callback function should register the desired collation using
- ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
- ** [sqlite3_create_collation_v2()].
- */
- SQLITE_API int sqlite3_collation_needed(
- sqlite3*,
- void*,
- void(*)(void*,sqlite3*,int eTextRep,const char*)
- );
- SQLITE_API int sqlite3_collation_needed16(
- sqlite3*,
- void*,
- void(*)(void*,sqlite3*,int eTextRep,const void*)
- );
- #ifdef SQLITE_HAS_CODEC
- /*
- ** Specify the key for an encrypted database. This routine should be
- ** called right after sqlite3_open().
- **
- ** The code to implement this API is not available in the public release
- ** of SQLite.
- */
- SQLITE_API int sqlite3_key(
- sqlite3 *db, /* Database to be rekeyed */
- const void *pKey, int nKey /* The key */
- );
- /*
- ** Change the key on an open database. If the current database is not
- ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
- ** database is decrypted.
- **
- ** The code to implement this API is not available in the public release
- ** of SQLite.
- */
- SQLITE_API int sqlite3_rekey(
- sqlite3 *db, /* Database to be rekeyed */
- const void *pKey, int nKey /* The new key */
- );
- /*
- ** Specify the activation key for a SEE database. Unless
- ** activated, none of the SEE routines will work.
- */
- SQLITE_API void sqlite3_activate_see(
- const char *zPassPhrase /* Activation phrase */
- );
- #endif
- #ifdef SQLITE_ENABLE_CEROD
- /*
- ** Specify the activation key for a CEROD database. Unless
- ** activated, none of the CEROD routines will work.
- */
- SQLITE_API void sqlite3_activate_cerod(
- const char *zPassPhrase /* Activation phrase */
- );
- #endif
- /*
- ** CAPI3REF: Suspend Execution For A Short Time
- **
- ** The sqlite3_sleep() function causes the current thread to suspend execution
- ** for at least a number of milliseconds specified in its parameter.
- **
- ** If the operating system does not support sleep requests with
- ** millisecond time resolution, then the time will be rounded up to
- ** the nearest second. The number of milliseconds of sleep actually
- ** requested from the operating system is returned.
- **
- ** ^SQLite implements this interface by calling the xSleep()
- ** method of the default [sqlite3_vfs] object. If the xSleep() method
- ** of the default VFS is not implemented correctly, or not implemented at
- ** all, then the behavior of sqlite3_sleep() may deviate from the description
- ** in the previous paragraphs.
- */
- SQLITE_API int sqlite3_sleep(int);
- /*
- ** CAPI3REF: Name Of The Folder Holding Temporary Files
- **
- ** ^(If this global variable is made to point to a string which is
- ** the name of a folder (a.k.a. directory), then all temporary files
- ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
- ** will be placed in that directory.)^ ^If this variable
- ** is a NULL pointer, then SQLite performs a search for an appropriate
- ** temporary file directory.
- **
- ** It is not safe to read or modify this variable in more than one
- ** thread at a time. It is not safe to read or modify this variable
- ** if a [database connection] is being used at the same time in a separate
- ** thread.
- ** It is intended that this variable be set once
- ** as part of process initialization and before any SQLite interface
- ** routines have been called and that this variable remain unchanged
- ** thereafter.
- **
- ** ^The [temp_store_directory pragma] may modify this variable and cause
- ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
- ** the [temp_store_directory pragma] always assumes that any string
- ** that this variable points to is held in memory obtained from
- ** [sqlite3_malloc] and the pragma may attempt to free that memory
- ** using [sqlite3_free].
- ** Hence, if this variable is modified directly, either it should be
- ** made NULL or made to point to memory obtained from [sqlite3_malloc]
- ** or else the use of the [temp_store_directory pragma] should be avoided.
- */
- SQLITE_API char *sqlite3_temp_directory;
- /*
- ** CAPI3REF: Test For Auto-Commit Mode
- ** KEYWORDS: {autocommit mode}
- **
- ** ^The sqlite3_get_autocommit() interface returns non-zero or
- ** zero if the given database connection is or is not in autocommit mode,
- ** respectively. ^Autocommit mode is on by default.
- ** ^Autocommit mode is disabled by a [BEGIN] statement.
- ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
- **
- ** If certain kinds of errors occur on a statement within a multi-statement
- ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
- ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
- ** transaction might be rolled back automatically. The only way to
- ** find out whether SQLite automatically rolled back the transaction after
- ** an error is to use this function.
- **
- ** If another thread changes the autocommit status of the database
- ** connection while this routine is running, then the return value
- ** is undefined.
- */
- SQLITE_API int sqlite3_get_autocommit(sqlite3*);
- /*
- ** CAPI3REF: Find The Database Handle Of A Prepared Statement
- **
- ** ^The sqlite3_db_handle interface returns the [database connection] handle
- ** to which a [prepared statement] belongs. ^The [database connection]
- ** returned by sqlite3_db_handle is the same [database connection]
- ** that was the first argument
- ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
- ** create the statement in the first place.
- */
- SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
- /*
- ** CAPI3REF: Return The Filename For A Database Connection
- **
- ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
- ** associated with database N of connection D. ^The main database file
- ** has the name "main". If there is no attached database N on the database
- ** connection D, or if database N is a temporary or in-memory database, then
- ** a NULL pointer is returned.
- **
- ** ^The filename returned by this function is the output of the
- ** xFullPathname method of the [VFS]. ^In other words, the filename
- ** will be an absolute pathname, even if the filename used
- ** to open the database originally was a URI or relative pathname.
- */
- SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
- /*
- ** CAPI3REF: Determine if a database is read-only
- **
- ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
- ** of connection D is read-only, 0 if it is read/write, or -1 if N is not
- ** the name of a database on connection D.
- */
- SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
- /*
- ** CAPI3REF: Find the next prepared statement
- **
- ** ^This interface returns a pointer to the next [prepared statement] after
- ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
- ** then this interface returns a pointer to the first prepared statement
- ** associated with the database connection pDb. ^If no prepared statement
- ** satisfies the conditions of this routine, it returns NULL.
- **
- ** The [database connection] pointer D in a call to
- ** [sqlite3_next_stmt(D,S)] must refer to an open database
- ** connection and in particular must not be a NULL pointer.
- */
- SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
- /*
- ** CAPI3REF: Commit And Rollback Notification Callbacks
- **
- ** ^The sqlite3_commit_hook() interface registers a callback
- ** function to be invoked whenever a transaction is [COMMIT | committed].
- ** ^Any callback set by a previous call to sqlite3_commit_hook()
- ** for the same database connection is overridden.
- ** ^The sqlite3_rollback_hook() interface registers a callback
- ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
- ** ^Any callback set by a previous call to sqlite3_rollback_hook()
- ** for the same database connection is overridden.
- ** ^The pArg argument is passed through to the callback.
- ** ^If the callback on a commit hook function returns non-zero,
- ** then the commit is converted into a rollback.
- **
- ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
- ** return the P argument from the previous call of the same function
- ** on the same [database connection] D, or NULL for
- ** the first call for each function on D.
- **
- ** The commit and rollback hook callbacks are not reentrant.
- ** The callback implementation must not do anything that will modify
- ** the database connection that invoked the callback. Any actions
- ** to modify the database connection must be deferred until after the
- ** completion of the [sqlite3_step()] call that triggered the commit
- ** or rollback hook in the first place.
- ** Note that running any other SQL statements, including SELECT statements,
- ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
- ** the database connections for the meaning of "modify" in this paragraph.
- **
- ** ^Registering a NULL function disables the callback.
- **
- ** ^When the commit hook callback routine returns zero, the [COMMIT]
- ** operation is allowed to continue normally. ^If the commit hook
- ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
- ** ^The rollback hook is invoked on a rollback that results from a commit
- ** hook returning non-zero, just as it would be with any other rollback.
- **
- ** ^For the purposes of this API, a transaction is said to have been
- ** rolled back if an explicit "ROLLBACK" statement is executed, or
- ** an error or constraint causes an implicit rollback to occur.
- ** ^The rollback callback is not invoked if a transaction is
- ** automatically rolled back because the database connection is closed.
- **
- ** See also the [sqlite3_update_hook()] interface.
- */
- SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
- SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
- /*
- ** CAPI3REF: Data Change Notification Callbacks
- **
- ** ^The sqlite3_update_hook() interface registers a callback function
- ** with the [database connection] identified by the first argument
- ** to be invoked whenever a row is updated, inserted or deleted.
- ** ^Any callback set by a previous call to this function
- ** for the same database connection is overridden.
- **
- ** ^The second argument is a pointer to the function to invoke when a
- ** row is updated, inserted or deleted.
- ** ^The first argument to the callback is a copy of the third argument
- ** to sqlite3_update_hook().
- ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
- ** or [SQLITE_UPDATE], depending on the operation that caused the callback
- ** to be invoked.
- ** ^The third and fourth arguments to the callback contain pointers to the
- ** database and table name containing the affected row.
- ** ^The final callback parameter is the [rowid] of the row.
- ** ^In the case of an update, this is the [rowid] after the update takes place.
- **
- ** ^(The update hook is not invoked when internal system tables are
- ** modified (i.e. sqlite_master and sqlite_sequence).)^
- **
- ** ^In the current implementation, the update hook
- ** is not invoked when duplication rows are deleted because of an
- ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
- ** invoked when rows are deleted using the [truncate optimization].
- ** The exceptions defined in this paragraph might change in a future
- ** release of SQLite.
- **
- ** The update hook implementation must not do anything that will modify
- ** the database connection that invoked the update hook. Any actions
- ** to modify the database connection must be deferred until after the
- ** completion of the [sqlite3_step()] call that triggered the update hook.
- ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
- ** database connections for the meaning of "modify" in this paragraph.
- **
- ** ^The sqlite3_update_hook(D,C,P) function
- ** returns the P argument from the previous call
- ** on the same [database connection] D, or NULL for
- ** the first call on D.
- **
- ** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
- ** interfaces.
- */
- SQLITE_API void *sqlite3_update_hook(
- sqlite3*,
- void(*)(void *,int ,char const *,char const *,sqlite3_int64),
- void*
- );
- /*
- ** CAPI3REF: Enable Or Disable Shared Pager Cache
- ** KEYWORDS: {shared cache}
- **
- ** ^(This routine enables or disables the sharing of the database cache
- ** and schema data structures between [database connection | connections]
- ** to the same database. Sharing is enabled if the argument is true
- ** and disabled if the argument is false.)^
- **
- ** ^Cache sharing is enabled and disabled for an entire process.
- ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
- ** sharing was enabled or disabled for each thread separately.
- **
- ** ^(The cache sharing mode set by this interface effects all subsequent
- ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
- ** Existing database connections continue use the sharing mode
- ** that was in effect at the time they were opened.)^
- **
- ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
- ** successfully. An [error code] is returned otherwise.)^
- **
- ** ^Shared cache is disabled by default. But this might change in
- ** future releases of SQLite. Applications that care about shared
- ** cache setting should set it explicitly.
- **
- ** See Also: [SQLite Shared-Cache Mode]
- */
- SQLITE_API int sqlite3_enable_shared_cache(int);
- /*
- ** CAPI3REF: Attempt To Free Heap Memory
- **
- ** ^The sqlite3_release_memory() interface attempts to free N bytes
- ** of heap memory by deallocating non-essential memory allocations
- ** held by the database library. Memory used to cache database
- ** pages to improve performance is an example of non-essential memory.
- ** ^sqlite3_release_memory() returns the number of bytes actually freed,
- ** which might be more or less than the amount requested.
- ** ^The sqlite3_release_memory() routine is a no-op returning zero
- ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
- **
- ** See also: [sqlite3_db_release_memory()]
- */
- SQLITE_API int sqlite3_release_memory(int);
- /*
- ** CAPI3REF: Free Memory Used By A Database Connection
- **
- ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
- ** memory as possible from database connection D. Unlike the
- ** [sqlite3_release_memory()] interface, this interface is effect even
- ** when then [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
- ** omitted.
- **
- ** See also: [sqlite3_release_memory()]
- */
- SQLITE_API int sqlite3_db_release_memory(sqlite3*);
- /*
- ** CAPI3REF: Impose A Limit On Heap Size
- **
- ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
- ** soft limit on the amount of heap memory that may be allocated by SQLite.
- ** ^SQLite strives to keep heap memory utilization below the soft heap
- ** limit by reducing the number of pages held in the page cache
- ** as heap memory usages approaches the limit.
- ** ^The soft heap limit is "soft" because even though SQLite strives to stay
- ** below the limit, it will exceed the limit rather than generate
- ** an [SQLITE_NOMEM] error. In other words, the soft heap limit
- ** is advisory only.
- **
- ** ^The return value from sqlite3_soft_heap_limit64() is the size of
- ** the soft heap limit prior to the call, or negative in the case of an
- ** error. ^If the argument N is negative
- ** then no change is made to the soft heap limit. Hence, the current
- ** size of the soft heap limit can be determined by invoking
- ** sqlite3_soft_heap_limit64() with a negative argument.
- **
- ** ^If the argument N is zero then the soft heap limit is disabled.
- **
- ** ^(The soft heap limit is not enforced in the current implementation
- ** if one or more of following conditions are true:
- **
- ** <ul>
- ** <li> The soft heap limit is set to zero.
- ** <li> Memory accounting is disabled using a combination of the
- ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
- ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
- ** <li> An alternative page cache implementation is specified using
- ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
- ** <li> The page cache allocates from its own memory pool supplied
- ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
- ** from the heap.
- ** </ul>)^
- **
- ** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
- ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
- ** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
- ** the soft heap limit is enforced on every memory allocation. Without
- ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
- ** when memory is allocated by the page cache. Testing suggests that because
- ** the page cache is the predominate memory user in SQLite, most
- ** applications will achieve adequate soft heap limit enforcement without
- ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
- **
- ** The circumstances under which SQLite will enforce the soft heap limit may
- ** changes in future releases of SQLite.
- */
- SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
- /*
- ** CAPI3REF: Deprecated Soft Heap Limit Interface
- ** DEPRECATED
- **
- ** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
- ** interface. This routine is provided for historical compatibility
- ** only. All new applications should use the
- ** [sqlite3_soft_heap_limit64()] interface rather than this one.
- */
- SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
- /*
- ** CAPI3REF: Extract Metadata About A Column Of A Table
- **
- ** ^This routine returns metadata about a specific column of a specific
- ** database table accessible using the [database connection] handle
- ** passed as the first function argument.
- **
- ** ^The column is identified by the second, third and fourth parameters to
- ** this function. ^The second parameter is either the name of the database
- ** (i.e. "main", "temp", or an attached database) containing the specified
- ** table or NULL. ^If it is NULL, then all attached databases are searched
- ** for the table using the same algorithm used by the database engine to
- ** resolve unqualified table references.
- **
- ** ^The third and fourth parameters to this function are the table and column
- ** name of the desired column, respectively. Neither of these parameters
- ** may be NULL.
- **
- ** ^Metadata is returned by writing to the memory locations passed as the 5th
- ** and subsequent parameters to this function. ^Any of these arguments may be
- ** NULL, in which case the corresponding element of metadata is omitted.
- **
- ** ^(<blockquote>
- ** <table border="1">
- ** <tr><th> Parameter <th> Output<br>Type <th> Description
- **
- ** <tr><td> 5th <td> const char* <td> Data type
- ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
- ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
- ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
- ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
- ** </table>
- ** </blockquote>)^
- **
- ** ^The memory pointed to by the character pointers returned for the
- ** declaration type and collation sequence is valid only until the next
- ** call to any SQLite API function.
- **
- ** ^If the specified table is actually a view, an [error code] is returned.
- **
- ** ^If the specified column is "rowid", "oid" or "_rowid_" and an
- ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
- ** parameters are set for the explicitly declared column. ^(If there is no
- ** explicitly declared [INTEGER PRIMARY KEY] column, then the output
- ** parameters are set as follows:
- **
- ** <pre>
- ** data type: "INTEGER"
- ** collation sequence: "BINARY"
- ** not null: 0
- ** primary key: 1
- ** auto increment: 0
- ** </pre>)^
- **
- ** ^(This function may load one or more schemas from database files. If an
- ** error occurs during this process, or if the requested table or column
- ** cannot be found, an [error code] is returned and an error message left
- ** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
- **
- ** ^This API is only available if the library was compiled with the
- ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
- */
- SQLITE_API int sqlite3_table_column_metadata(
- sqlite3 *db, /* Connection handle */
- const char *zDbName, /* Database name or NULL */
- const char *zTableName, /* Table name */
- const char *zColumnName, /* Column name */
- char const **pzDataType, /* OUTPUT: Declared data type */
- char const **pzCollSeq, /* OUTPUT: Collation sequence name */
- int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
- int *pPrimaryKey, /* OUTPUT: True if column part of PK */
- int *pAutoinc /* OUTPUT: True if column is auto-increment */
- );
- /*
- ** CAPI3REF: Load An Extension
- **
- ** ^This interface loads an SQLite extension library from the named file.
- **
- ** ^The sqlite3_load_extension() interface attempts to load an
- ** SQLite extension library contained in the file zFile.
- **
- ** ^The entry point is zProc.
- ** ^zProc may be 0, in which case the name of the entry point
- ** defaults to "sqlite3_extension_init".
- ** ^The sqlite3_load_extension() interface returns
- ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
- ** ^If an error occurs and pzErrMsg is not 0, then the
- ** [sqlite3_load_extension()] interface shall attempt to
- ** fill *pzErrMsg with error message text stored in memory
- ** obtained from [sqlite3_malloc()]. The calling function
- ** should free this memory by calling [sqlite3_free()].
- **
- ** ^Extension loading must be enabled using
- ** [sqlite3_enable_load_extension()] prior to calling this API,
- ** otherwise an error will be returned.
- **
- ** See also the [load_extension() SQL function].
- */
- SQLITE_API int sqlite3_load_extension(
- sqlite3 *db, /* Load the extension into this database connection */
- const char *zFile, /* Name of the shared library containing extension */
- const char *zProc, /* Entry point. Derived from zFile if 0 */
- char **pzErrMsg /* Put error message here if not 0 */
- );
- /*
- ** CAPI3REF: Enable Or Disable Extension Loading
- **
- ** ^So as not to open security holes in older applications that are
- ** unprepared to deal with extension loading, and as a means of disabling
- ** extension loading while evaluating user-entered SQL, the following API
- ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
- **
- ** ^Extension loading is off by default. See ticket #1863.
- ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
- ** to turn extension loading on and call it with onoff==0 to turn
- ** it back off again.
- */
- SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
- /*
- ** CAPI3REF: Automatically Load Statically Linked Extensions
- **
- ** ^This interface causes the xEntryPoint() function to be invoked for
- ** each new [database connection] that is created. The idea here is that
- ** xEntryPoint() is the entry point for a statically linked SQLite extension
- ** that is to be automatically loaded into all new database connections.
- **
- ** ^(Even though the function prototype shows that xEntryPoint() takes
- ** no arguments and returns void, SQLite invokes xEntryPoint() with three
- ** arguments and expects and integer result as if the signature of the
- ** entry point where as follows:
- **
- ** <blockquote><pre>
- ** int xEntryPoint(
- ** sqlite3 *db,
- ** const char **pzErrMsg,
- ** const struct sqlite3_api_routines *pThunk
- ** );
- ** </pre></blockquote>)^
- **
- ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
- ** point to an appropriate error message (obtained from [sqlite3_mprintf()])
- ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
- ** is NULL before calling the xEntryPoint(). ^SQLite will invoke
- ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
- ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
- ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
- **
- ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
- ** on the list of automatic extensions is a harmless no-op. ^No entry point
- ** will be called more than once for each database connection that is opened.
- **
- ** See also: [sqlite3_reset_auto_extension()].
- */
- SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
- /*
- ** CAPI3REF: Reset Automatic Extension Loading
- **
- ** ^This interface disables all automatic extensions previously
- ** registered using [sqlite3_auto_extension()].
- */
- SQLITE_API void sqlite3_reset_auto_extension(void);
- /*
- ** The interface to the virtual-table mechanism is currently considered
- ** to be experimental. The interface might change in incompatible ways.
- ** If this is a problem for you, do not use the interface at this time.
- **
- ** When the virtual-table mechanism stabilizes, we will declare the
- ** interface fixed, support it indefinitely, and remove this comment.
- */
- /*
- ** Structures used by the virtual table interface
- */
- typedef struct sqlite3_vtab sqlite3_vtab;
- typedef struct sqlite3_index_info sqlite3_index_info;
- typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
- typedef struct sqlite3_module sqlite3_module;
- /*
- ** CAPI3REF: Virtual Table Object
- ** KEYWORDS: sqlite3_module {virtual table module}
- **
- ** This structure, sometimes called a "virtual table module",
- ** defines the implementation of a [virtual tables].
- ** This structure consists mostly of methods for the module.
- **
- ** ^A virtual table module is created by filling in a persistent
- ** instance of this structure and passing a pointer to that instance
- ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
- ** ^The registration remains valid until it is replaced by a different
- ** module or until the [database connection] closes. The content
- ** of this structure must not change while it is registered with
- ** any database connection.
- */
- struct sqlite3_module {
- int iVersion;
- int (*xCreate)(sqlite3*, void *pAux,
- int argc, const char *const*argv,
- sqlite3_vtab **ppVTab, char**);
- int (*xConnect)(sqlite3*, void *pAux,
- int argc, const char *const*argv,
- sqlite3_vtab **ppVTab, char**);
- int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
- int (*xDisconnect)(sqlite3_vtab *pVTab);
- int (*xDestroy)(sqlite3_vtab *pVTab);
- int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
- int (*xClose)(sqlite3_vtab_cursor*);
- int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
- int argc, sqlite3_value **argv);
- int (*xNext)(sqlite3_vtab_cursor*);
- int (*xEof)(sqlite3_vtab_cursor*);
- int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
- int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
- int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
- int (*xBegin)(sqlite3_vtab *pVTab);
- int (*xSync)(sqlite3_vtab *pVTab);
- int (*xCommit)(sqlite3_vtab *pVTab);
- int (*xRollback)(sqlite3_vtab *pVTab);
- int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
- void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
- void **ppArg);
- int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
- /* The methods above are in version 1 of the sqlite_module object. Those
- ** below are for version 2 and greater. */
- int (*xSavepoint)(sqlite3_vtab *pVTab, int);
- int (*xRelease)(sqlite3_vtab *pVTab, int);
- int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
- };
- /*
- ** CAPI3REF: Virtual Table Indexing Information
- ** KEYWORDS: sqlite3_index_info
- **
- ** The sqlite3_index_info structure and its substructures is used as part
- ** of the [virtual table] interface to
- ** pass information into and receive the reply from the [xBestIndex]
- ** method of a [virtual table module]. The fields under **Inputs** are the
- ** inputs to xBestIndex and are read-only. xBestIndex inserts its
- ** results into the **Outputs** fields.
- **
- ** ^(The aConstraint[] array records WHERE clause constraints of the form:
- **
- ** <blockquote>column OP expr</blockquote>
- **
- ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
- ** stored in aConstraint[].op using one of the
- ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
- ** ^(The index of the column is stored in
- ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
- ** expr on the right-hand side can be evaluated (and thus the constraint
- ** is usable) and false if it cannot.)^
- **
- ** ^The optimizer automatically inverts terms of the form "expr OP column"
- ** and makes other simplifications to the WHERE clause in an attempt to
- ** get as many WHERE clause terms into the form shown above as possible.
- ** ^The aConstraint[] array only reports WHERE clause terms that are
- ** relevant to the particular virtual table being queried.
- **
- ** ^Information about the ORDER BY clause is stored in aOrderBy[].
- ** ^Each term of aOrderBy records a column of the ORDER BY clause.
- **
- ** The [xBestIndex] method must fill aConstraintUsage[] with information
- ** about what parameters to pass to xFilter. ^If argvIndex>0 then
- ** the right-hand side of the corresponding aConstraint[] is evaluated
- ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
- ** is true, then the constraint is assumed to be fully handled by the
- ** virtual table and is not checked again by SQLite.)^
- **
- ** ^The idxNum and idxPtr values are recorded and passed into the
- ** [xFilter] method.
- ** ^[sqlite3_free()] is used to free idxPtr if and only if
- ** needToFreeIdxPtr is true.
- **
- ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
- ** the correct order to satisfy the ORDER BY clause so that no separate
- ** sorting step is required.
- **
- ** ^The estimatedCost value is an estimate of the cost of doing the
- ** particular lookup. A full scan of a table with N entries should have
- ** a cost of N. A binary search of a table of N entries should have a
- ** cost of approximately log(N).
- */
- struct sqlite3_index_info {
- /* Inputs */
- int nConstraint; /* Number of entries in aConstraint */
- struct sqlite3_index_constraint {
- int iColumn; /* Column on left-hand side of constraint */
- unsigned char op; /* Constraint operator */
- unsigned char usable; /* True if this constraint is usable */
- int iTermOffset; /* Used internally - xBestIndex should ignore */
- } *aConstraint; /* Table of WHERE clause constraints */
- int nOrderBy; /* Number of terms in the ORDER BY clause */
- struct sqlite3_index_orderby {
- int iColumn; /* Column number */
- unsigned char desc; /* True for DESC. False for ASC. */
- } *aOrderBy; /* The ORDER BY clause */
- /* Outputs */
- struct sqlite3_index_constraint_usage {
- int argvIndex; /* if >0, constraint is part of argv to xFilter */
- unsigned char omit; /* Do not code a test for this constraint */
- } *aConstraintUsage;
- int idxNum; /* Number used to identify the index */
- char *idxStr; /* String, possibly obtained from sqlite3_malloc */
- int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
- int orderByConsumed; /* True if output is already ordered */
- double estimatedCost; /* Estimated cost of using this index */
- };
- /*
- ** CAPI3REF: Virtual Table Constraint Operator Codes
- **
- ** These macros defined the allowed values for the
- ** [sqlite3_index_info].aConstraint[].op field. Each value represents
- ** an operator that is part of a constraint term in the wHERE clause of
- ** a query that uses a [virtual table].
- */
- #define SQLITE_INDEX_CONSTRAINT_EQ 2
- #define SQLITE_INDEX_CONSTRAINT_GT 4
- #define SQLITE_INDEX_CONSTRAINT_LE 8
- #define SQLITE_INDEX_CONSTRAINT_LT 16
- #define SQLITE_INDEX_CONSTRAINT_GE 32
- #define SQLITE_INDEX_CONSTRAINT_MATCH 64
- /*
- ** CAPI3REF: Register A Virtual Table Implementation
- **
- ** ^These routines are used to register a new [virtual table module] name.
- ** ^Module names must be registered before
- ** creating a new [virtual table] using the module and before using a
- ** preexisting [virtual table] for the module.
- **
- ** ^The module name is registered on the [database connection] specified
- ** by the first parameter. ^The name of the module is given by the
- ** second parameter. ^The third parameter is a pointer to
- ** the implementation of the [virtual table module]. ^The fourth
- ** parameter is an arbitrary client data pointer that is passed through
- ** into the [xCreate] and [xConnect] methods of the virtual table module
- ** when a new virtual table is be being created or reinitialized.
- **
- ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
- ** is a pointer to a destructor for the pClientData. ^SQLite will
- ** invoke the destructor function (if it is not NULL) when SQLite
- ** no longer needs the pClientData pointer. ^The destructor will also
- ** be invoked if the call to sqlite3_create_module_v2() fails.
- ** ^The sqlite3_create_module()
- ** interface is equivalent to sqlite3_create_module_v2() with a NULL
- ** destructor.
- */
- SQLITE_API int sqlite3_create_module(
- sqlite3 *db, /* SQLite connection to register module with */
- const char *zName, /* Name of the module */
- const sqlite3_module *p, /* Methods for the module */
- void *pClientData /* Client data for xCreate/xConnect */
- );
- SQLITE_API int sqlite3_create_module_v2(
- sqlite3 *db, /* SQLite connection to register module with */
- const char *zName, /* Name of the module */
- const sqlite3_module *p, /* Methods for the module */
- void *pClientData, /* Client data for xCreate/xConnect */
- void(*xDestroy)(void*) /* Module destructor function */
- );
- /*
- ** CAPI3REF: Virtual Table Instance Object
- ** KEYWORDS: sqlite3_vtab
- **
- ** Every [virtual table module] implementation uses a subclass
- ** of this object to describe a particular instance
- ** of the [virtual table]. Each subclass will
- ** be tailored to the specific needs of the module implementation.
- ** The purpose of this superclass is to define certain fields that are
- ** common to all module implementations.
- **
- ** ^Virtual tables methods can set an error message by assigning a
- ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
- ** take care that any prior string is freed by a call to [sqlite3_free()]
- ** prior to assigning a new string to zErrMsg. ^After the error message
- ** is delivered up to the client application, the string will be automatically
- ** freed by sqlite3_free() and the zErrMsg field will be zeroed.
- */
- struct sqlite3_vtab {
- const sqlite3_module *pModule; /* The module for this virtual table */
- int nRef; /* NO LONGER USED */
- char *zErrMsg; /* Error message from sqlite3_mprintf() */
- /* Virtual table implementations will typically add additional fields */
- };
- /*
- ** CAPI3REF: Virtual Table Cursor Object
- ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
- **
- ** Every [virtual table module] implementation uses a subclass of the
- ** following structure to describe cursors that point into the
- ** [virtual table] and are used
- ** to loop through the virtual table. Cursors are created using the
- ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
- ** by the [sqlite3_module.xClose | xClose] method. Cursors are used
- ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
- ** of the module. Each module implementation will define
- ** the content of a cursor structure to suit its own needs.
- **
- ** This superclass exists in order to define fields of the cursor that
- ** are common to all implementations.
- */
- struct sqlite3_vtab_cursor {
- sqlite3_vtab *pVtab; /* Virtual table of this cursor */
- /* Virtual table implementations will typically add additional fields */
- };
- /*
- ** CAPI3REF: Declare The Schema Of A Virtual Table
- **
- ** ^The [xCreate] and [xConnect] methods of a
- ** [virtual table module] call this interface
- ** to declare the format (the names and datatypes of the columns) of
- ** the virtual tables they implement.
- */
- SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
- /*
- ** CAPI3REF: Overload A Function For A Virtual Table
- **
- ** ^(Virtual tables can provide alternative implementations of functions
- ** using the [xFindFunction] method of the [virtual table module].
- ** But global versions of those functions
- ** must exist in order to be overloaded.)^
- **
- ** ^(This API makes sure a global version of a function with a particular
- ** name and number of parameters exists. If no such function exists
- ** before this API is called, a new function is created.)^ ^The implementation
- ** of the new function always causes an exception to be thrown. So
- ** the new function is not good for anything by itself. Its only
- ** purpose is to be a placeholder function that can be overloaded
- ** by a [virtual table].
- */
- SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
- /*
- ** The interface to the virtual-table mechanism defined above (back up
- ** to a comment remarkably similar to this one) is currently considered
- ** to be experimental. The interface might change in incompatible ways.
- ** If this is a problem for you, do not use the interface at this time.
- **
- ** When the virtual-table mechanism stabilizes, we will declare the
- ** interface fixed, support it indefinitely, and remove this comment.
- */
- /*
- ** CAPI3REF: A Handle To An Open BLOB
- ** KEYWORDS: {BLOB handle} {BLOB handles}
- **
- ** An instance of this object represents an open BLOB on which
- ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
- ** ^Objects of this type are created by [sqlite3_blob_open()]
- ** and destroyed by [sqlite3_blob_close()].
- ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
- ** can be used to read or write small subsections of the BLOB.
- ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
- */
- typedef struct sqlite3_blob sqlite3_blob;
- /*
- ** CAPI3REF: Open A BLOB For Incremental I/O
- **
- ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
- ** in row iRow, column zColumn, table zTable in database zDb;
- ** in other words, the same BLOB that would be selected by:
- **
- ** <pre>
- ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
- ** </pre>)^
- **
- ** ^If the flags parameter is non-zero, then the BLOB is opened for read
- ** and write access. ^If it is zero, the BLOB is opened for read access.
- ** ^It is not possible to open a column that is part of an index or primary
- ** key for writing. ^If [foreign key constraints] are enabled, it is
- ** not possible to open a column that is part of a [child key] for writing.
- **
- ** ^Note that the database name is not the filename that contains
- ** the database but rather the symbolic name of the database that
- ** appears after the AS keyword when the database is connected using [ATTACH].
- ** ^For the main database file, the database name is "main".
- ** ^For TEMP tables, the database name is "temp".
- **
- ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
- ** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
- ** to be a null pointer.)^
- ** ^This function sets the [database connection] error code and message
- ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
- ** functions. ^Note that the *ppBlob variable is always initialized in a
- ** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
- ** regardless of the success or failure of this routine.
- **
- ** ^(If the row that a BLOB handle points to is modified by an
- ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
- ** then the BLOB handle is marked as "expired".
- ** This is true if any column of the row is changed, even a column
- ** other than the one the BLOB handle is open on.)^
- ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
- ** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
- ** ^(Changes written into a BLOB prior to the BLOB expiring are not
- ** rolled back by the expiration of the BLOB. Such changes will eventually
- ** commit if the transaction continues to completion.)^
- **
- ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
- ** the opened blob. ^The size of a blob may not be changed by this
- ** interface. Use the [UPDATE] SQL command to change the size of a
- ** blob.
- **
- ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
- ** and the built-in [zeroblob] SQL function can be used, if desired,
- ** to create an empty, zero-filled blob in which to read or write using
- ** this interface.
- **
- ** To avoid a resource leak, every open [BLOB handle] should eventually
- ** be released by a call to [sqlite3_blob_close()].
- */
- SQLITE_API int sqlite3_blob_open(
- sqlite3*,
- const char *zDb,
- const char *zTable,
- const char *zColumn,
- sqlite3_int64 iRow,
- int flags,
- sqlite3_blob **ppBlob
- );
- /*
- ** CAPI3REF: Move a BLOB Handle to a New Row
- **
- ** ^This function is used to move an existing blob handle so that it points
- ** to a different row of the same database table. ^The new row is identified
- ** by the rowid value passed as the second argument. Only the row can be
- ** changed. ^The database, table and column on which the blob handle is open
- ** remain the same. Moving an existing blob handle to a new row can be
- ** faster than closing the existing handle and opening a new one.
- **
- ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
- ** it must exist and there must be either a blob or text value stored in
- ** the nominated column.)^ ^If the new row is not present in the table, or if
- ** it does not contain a blob or text value, or if another error occurs, an
- ** SQLite error code is returned and the blob handle is considered aborted.
- ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
- ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
- ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
- ** always returns zero.
- **
- ** ^This function sets the database handle error code and message.
- */
- SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
- /*
- ** CAPI3REF: Close A BLOB Handle
- **
- ** ^Closes an open [BLOB handle].
- **
- ** ^Closing a BLOB shall cause the current transaction to commit
- ** if there are no other BLOBs, no pending prepared statements, and the
- ** database connection is in [autocommit mode].
- ** ^If any writes were made to the BLOB, they might be held in cache
- ** until the close operation if they will fit.
- **
- ** ^(Closing the BLOB often forces the changes
- ** out to disk and so if any I/O errors occur, they will likely occur
- ** at the time when the BLOB is closed. Any errors that occur during
- ** closing are reported as a non-zero return value.)^
- **
- ** ^(The BLOB is closed unconditionally. Even if this routine returns
- ** an error code, the BLOB is still closed.)^
- **
- ** ^Calling this routine with a null pointer (such as would be returned
- ** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
- */
- SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
- /*
- ** CAPI3REF: Return The Size Of An Open BLOB
- **
- ** ^Returns the size in bytes of the BLOB accessible via the
- ** successfully opened [BLOB handle] in its only argument. ^The
- ** incremental blob I/O routines can only read or overwriting existing
- ** blob content; they cannot change the size of a blob.
- **
- ** This routine only works on a [BLOB handle] which has been created
- ** by a prior successful call to [sqlite3_blob_open()] and which has not
- ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
- ** to this routine results in undefined and probably undesirable behavior.
- */
- SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
- /*
- ** CAPI3REF: Read Data From A BLOB Incrementally
- **
- ** ^(This function is used to read data from an open [BLOB handle] into a
- ** caller-supplied buffer. N bytes of data are copied into buffer Z
- ** from the open BLOB, starting at offset iOffset.)^
- **
- ** ^If offset iOffset is less than N bytes from the end of the BLOB,
- ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
- ** less than zero, [SQLITE_ERROR] is returned and no data is read.
- ** ^The size of the blob (and hence the maximum value of N+iOffset)
- ** can be determined using the [sqlite3_blob_bytes()] interface.
- **
- ** ^An attempt to read from an expired [BLOB handle] fails with an
- ** error code of [SQLITE_ABORT].
- **
- ** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
- ** Otherwise, an [error code] or an [extended error code] is returned.)^
- **
- ** This routine only works on a [BLOB handle] which has been created
- ** by a prior successful call to [sqlite3_blob_open()] and which has not
- ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
- ** to this routine results in undefined and probably undesirable behavior.
- **
- ** See also: [sqlite3_blob_write()].
- */
- SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
- /*
- ** CAPI3REF: Write Data Into A BLOB Incrementally
- **
- ** ^This function is used to write data into an open [BLOB handle] from a
- ** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
- ** into the open BLOB, starting at offset iOffset.
- **
- ** ^If the [BLOB handle] passed as the first argument was not opened for
- ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
- ** this function returns [SQLITE_READONLY].
- **
- ** ^This function may only modify the contents of the BLOB; it is
- ** not possible to increase the size of a BLOB using this API.
- ** ^If offset iOffset is less than N bytes from the end of the BLOB,
- ** [SQLITE_ERROR] is returned and no data is written. ^If N is
- ** less than zero [SQLITE_ERROR] is returned and no data is written.
- ** The size of the BLOB (and hence the maximum value of N+iOffset)
- ** can be determined using the [sqlite3_blob_bytes()] interface.
- **
- ** ^An attempt to write to an expired [BLOB handle] fails with an
- ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
- ** before the [BLOB handle] expired are not rolled back by the
- ** expiration of the handle, though of course those changes might
- ** have been overwritten by the statement that expired the BLOB handle
- ** or by other independent statements.
- **
- ** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
- ** Otherwise, an [error code] or an [extended error code] is returned.)^
- **
- ** This routine only works on a [BLOB handle] which has been created
- ** by a prior successful call to [sqlite3_blob_open()] and which has not
- ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
- ** to this routine results in undefined and probably undesirable behavior.
- **
- ** See also: [sqlite3_blob_read()].
- */
- SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
- /*
- ** CAPI3REF: Virtual File System Objects
- **
- ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
- ** that SQLite uses to interact
- ** with the underlying operating system. Most SQLite builds come with a
- ** single default VFS that is appropriate for the host computer.
- ** New VFSes can be registered and existing VFSes can be unregistered.
- ** The following interfaces are provided.
- **
- ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
- ** ^Names are case sensitive.
- ** ^Names are zero-terminated UTF-8 strings.
- ** ^If there is no match, a NULL pointer is returned.
- ** ^If zVfsName is NULL then the default VFS is returned.
- **
- ** ^New VFSes are registered with sqlite3_vfs_register().
- ** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
- ** ^The same VFS can be registered multiple times without injury.
- ** ^To make an existing VFS into the default VFS, register it again
- ** with the makeDflt flag set. If two different VFSes with the
- ** same name are registered, the behavior is undefined. If a
- ** VFS is registered with a name that is NULL or an empty string,
- ** then the behavior is undefined.
- **
- ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
- ** ^(If the default VFS is unregistered, another VFS is chosen as
- ** the default. The choice for the new VFS is arbitrary.)^
- */
- SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
- SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
- SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
- /*
- ** CAPI3REF: Mutexes
- **
- ** The SQLite core uses these routines for thread
- ** synchronization. Though they are intended for internal
- ** use by SQLite, code that links against SQLite is
- ** permitted to use any of these routines.
- **
- ** The SQLite source code contains multiple implementations
- ** of these mutex routines. An appropriate implementation
- ** is selected automatically at compile-time. ^(The following
- ** implementations are available in the SQLite core:
- **
- ** <ul>
- ** <li> SQLITE_MUTEX_OS2
- ** <li> SQLITE_MUTEX_PTHREADS
- ** <li> SQLITE_MUTEX_W32
- ** <li> SQLITE_MUTEX_NOOP
- ** </ul>)^
- **
- ** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
- ** that does no real locking and is appropriate for use in
- ** a single-threaded application. ^The SQLITE_MUTEX_OS2,
- ** SQLITE_MUTEX_PTHREADS, and SQLITE_MUTEX_W32 implementations
- ** are appropriate for use on OS/2, Unix, and Windows.
- **
- ** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
- ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
- ** implementation is included with the library. In this case the
- ** application must supply a custom mutex implementation using the
- ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
- ** before calling sqlite3_initialize() or any other public sqlite3_
- ** function that calls sqlite3_initialize().)^
- **
- ** ^The sqlite3_mutex_alloc() routine allocates a new
- ** mutex and returns a pointer to it. ^If it returns NULL
- ** that means that a mutex could not be allocated. ^SQLite
- ** will unwind its stack and return an error. ^(The argument
- ** to sqlite3_mutex_alloc() is one of these integer constants:
- **
- ** <ul>
- ** <li> SQLITE_MUTEX_FAST
- ** <li> SQLITE_MUTEX_RECURSIVE
- ** <li> SQLITE_MUTEX_STATIC_MASTER
- ** <li> SQLITE_MUTEX_STATIC_MEM
- ** <li> SQLITE_MUTEX_STATIC_MEM2
- ** <li> SQLITE_MUTEX_STATIC_PRNG
- ** <li> SQLITE_MUTEX_STATIC_LRU
- ** <li> SQLITE_MUTEX_STATIC_LRU2
- ** </ul>)^
- **
- ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
- ** cause sqlite3_mutex_alloc() to create
- ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
- ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
- ** The mutex implementation does not need to make a distinction
- ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
- ** not want to. ^SQLite will only request a recursive mutex in
- ** cases where it really needs one. ^If a faster non-recursive mutex
- ** implementation is available on the host platform, the mutex subsystem
- ** might return such a mutex in response to SQLITE_MUTEX_FAST.
- **
- ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
- ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
- ** a pointer to a static preexisting mutex. ^Six static mutexes are
- ** used by the current version of SQLite. Future versions of SQLite
- ** may add additional static mutexes. Static mutexes are for internal
- ** use by SQLite only. Applications that use SQLite mutexes should
- ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
- ** SQLITE_MUTEX_RECURSIVE.
- **
- ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
- ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
- ** returns a different mutex on every call. ^But for the static
- ** mutex types, the same mutex is returned on every call that has
- ** the same type number.
- **
- ** ^The sqlite3_mutex_free() routine deallocates a previously
- ** allocated dynamic mutex. ^SQLite is careful to deallocate every
- ** dynamic mutex that it allocates. The dynamic mutexes must not be in
- ** use when they are deallocated. Attempting to deallocate a static
- ** mutex results in undefined behavior. ^SQLite never deallocates
- ** a static mutex.
- **
- ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
- ** to enter a mutex. ^If another thread is already within the mutex,
- ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
- ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
- ** upon successful entry. ^(Mutexes created using
- ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
- ** In such cases the,
- ** mutex must be exited an equal number of times before another thread
- ** can enter.)^ ^(If the same thread tries to enter any other
- ** kind of mutex more than once, the behavior is undefined.
- ** SQLite will never exhibit
- ** such behavior in its own use of mutexes.)^
- **
- ** ^(Some systems (for example, Windows 95) do not support the operation
- ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
- ** will always return SQLITE_BUSY. The SQLite core only ever uses
- ** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
- **
- ** ^The sqlite3_mutex_leave() routine exits a mutex that was
- ** previously entered by the same thread. ^(The behavior
- ** is undefined if the mutex is not currently entered by the
- ** calling thread or is not currently allocated. SQLite will
- ** never do either.)^
- **
- ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
- ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
- ** behave as no-ops.
- **
- ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
- */
- SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
- SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
- SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
- SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
- SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
- /*
- ** CAPI3REF: Mutex Methods Object
- **
- ** An instance of this structure defines the low-level routines
- ** used to allocate and use mutexes.
- **
- ** Usually, the default mutex implementations provided by SQLite are
- ** sufficient, however the user has the option of substituting a custom
- ** implementation for specialized deployments or systems for which SQLite
- ** does not provide a suitable implementation. In this case, the user
- ** creates and populates an instance of this structure to pass
- ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
- ** Additionally, an instance of this structure can be used as an
- ** output variable when querying the system for the current mutex
- ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
- **
- ** ^The xMutexInit method defined by this structure is invoked as
- ** part of system initialization by the sqlite3_initialize() function.
- ** ^The xMutexInit routine is called by SQLite exactly once for each
- ** effective call to [sqlite3_initialize()].
- **
- ** ^The xMutexEnd method defined by this structure is invoked as
- ** part of system shutdown by the sqlite3_shutdown() function. The
- ** implementation of this method is expected to release all outstanding
- ** resources obtained by the mutex methods implementation, especially
- ** those obtained by the xMutexInit method. ^The xMutexEnd()
- ** interface is invoked exactly once for each call to [sqlite3_shutdown()].
- **
- ** ^(The remaining seven methods defined by this structure (xMutexAlloc,
- ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
- ** xMutexNotheld) implement the following interfaces (respectively):
- **
- ** <ul>
- ** <li> [sqlite3_mutex_alloc()] </li>
- ** <li> [sqlite3_mutex_free()] </li>
- ** <li> [sqlite3_mutex_enter()] </li>
- ** <li> [sqlite3_mutex_try()] </li>
- ** <li> [sqlite3_mutex_leave()] </li>
- ** <li> [sqlite3_mutex_held()] </li>
- ** <li> [sqlite3_mutex_notheld()] </li>
- ** </ul>)^
- **
- ** The only difference is that the public sqlite3_XXX functions enumerated
- ** above silently ignore any invocations that pass a NULL pointer instead
- ** of a valid mutex handle. The implementations of the methods defined
- ** by this structure are not required to handle this case, the results
- ** of passing a NULL pointer instead of a valid mutex handle are undefined
- ** (i.e. it is acceptable to provide an implementation that segfaults if
- ** it is passed a NULL pointer).
- **
- ** The xMutexInit() method must be threadsafe. ^It must be harmless to
- ** invoke xMutexInit() multiple times within the same process and without
- ** intervening calls to xMutexEnd(). Second and subsequent calls to
- ** xMutexInit() must be no-ops.
- **
- ** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
- ** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
- ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
- ** memory allocation for a fast or recursive mutex.
- **
- ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
- ** called, but only if the prior call to xMutexInit returned SQLITE_OK.
- ** If xMutexInit fails in any way, it is expected to clean up after itself
- ** prior to returning.
- */
- typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
- struct sqlite3_mutex_methods {
- int (*xMutexInit)(void);
- int (*xMutexEnd)(void);
- sqlite3_mutex *(*xMutexAlloc)(int);
- void (*xMutexFree)(sqlite3_mutex *);
- void (*xMutexEnter)(sqlite3_mutex *);
- int (*xMutexTry)(sqlite3_mutex *);
- void (*xMutexLeave)(sqlite3_mutex *);
- int (*xMutexHeld)(sqlite3_mutex *);
- int (*xMutexNotheld)(sqlite3_mutex *);
- };
- /*
- ** CAPI3REF: Mutex Verification Routines
- **
- ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
- ** are intended for use inside assert() statements. ^The SQLite core
- ** never uses these routines except inside an assert() and applications
- ** are advised to follow the lead of the core. ^The SQLite core only
- ** provides implementations for these routines when it is compiled
- ** with the SQLITE_DEBUG flag. ^External mutex implementations
- ** are only required to provide these routines if SQLITE_DEBUG is
- ** defined and if NDEBUG is not defined.
- **
- ** ^These routines should return true if the mutex in their argument
- ** is held or not held, respectively, by the calling thread.
- **
- ** ^The implementation is not required to provide versions of these
- ** routines that actually work. If the implementation does not provide working
- ** versions of these routines, it should at least provide stubs that always
- ** return true so that one does not get spurious assertion failures.
- **
- ** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
- ** the routine should return 1. This seems counter-intuitive since
- ** clearly the mutex cannot be held if it does not exist. But
- ** the reason the mutex does not exist is because the build is not
- ** using mutexes. And we do not want the assert() containing the
- ** call to sqlite3_mutex_held() to fail, so a non-zero return is
- ** the appropriate thing to do. ^The sqlite3_mutex_notheld()
- ** interface should also return 1 when given a NULL pointer.
- */
- #ifndef NDEBUG
- SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
- SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
- #endif
- /*
- ** CAPI3REF: Mutex Types
- **
- ** The [sqlite3_mutex_alloc()] interface takes a single argument
- ** which is one of these integer constants.
- **
- ** The set of static mutexes may change from one SQLite release to the
- ** next. Applications that override the built-in mutex logic must be
- ** prepared to accommodate additional static mutexes.
- */
- #define SQLITE_MUTEX_FAST 0
- #define SQLITE_MUTEX_RECURSIVE 1
- #define SQLITE_MUTEX_STATIC_MASTER 2
- #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
- #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
- #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
- #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
- #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
- #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
- #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
- /*
- ** CAPI3REF: Retrieve the mutex for a database connection
- **
- ** ^This interface returns a pointer the [sqlite3_mutex] object that
- ** serializes access to the [database connection] given in the argument
- ** when the [threading mode] is Serialized.
- ** ^If the [threading mode] is Single-thread or Multi-thread then this
- ** routine returns a NULL pointer.
- */
- SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
- /*
- ** CAPI3REF: Low-Level Control Of Database Files
- **
- ** ^The [sqlite3_file_control()] interface makes a direct call to the
- ** xFileControl method for the [sqlite3_io_methods] object associated
- ** with a particular database identified by the second argument. ^The
- ** name of the database is "main" for the main database or "temp" for the
- ** TEMP database, or the name that appears after the AS keyword for
- ** databases that are added using the [ATTACH] SQL command.
- ** ^A NULL pointer can be used in place of "main" to refer to the
- ** main database file.
- ** ^The third and fourth parameters to this routine
- ** are passed directly through to the second and third parameters of
- ** the xFileControl method. ^The return value of the xFileControl
- ** method becomes the return value of this routine.
- **
- ** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
- ** a pointer to the underlying [sqlite3_file] object to be written into
- ** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER
- ** case is a short-circuit path which does not actually invoke the
- ** underlying sqlite3_io_methods.xFileControl method.
- **
- ** ^If the second parameter (zDbName) does not match the name of any
- ** open database file, then SQLITE_ERROR is returned. ^This error
- ** code is not remembered and will not be recalled by [sqlite3_errcode()]
- ** or [sqlite3_errmsg()]. The underlying xFileControl method might
- ** also return SQLITE_ERROR. There is no way to distinguish between
- ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
- ** xFileControl method.
- **
- ** See also: [SQLITE_FCNTL_LOCKSTATE]
- */
- SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
- /*
- ** CAPI3REF: Testing Interface
- **
- ** ^The sqlite3_test_control() interface is used to read out internal
- ** state of SQLite and to inject faults into SQLite for testing
- ** purposes. ^The first parameter is an operation code that determines
- ** the number, meaning, and operation of all subsequent parameters.
- **
- ** This interface is not for use by applications. It exists solely
- ** for verifying the correct operation of the SQLite library. Depending
- ** on how the SQLite library is compiled, this interface might not exist.
- **
- ** The details of the operation codes, their meanings, the parameters
- ** they take, and what they do are all subject to change without notice.
- ** Unlike most of the SQLite API, this function is not guaranteed to
- ** operate consistently from one release to the next.
- */
- SQLITE_API int sqlite3_test_control(int op, ...);
- /*
- ** CAPI3REF: Testing Interface Operation Codes
- **
- ** These constants are the valid operation code parameters used
- ** as the first argument to [sqlite3_test_control()].
- **
- ** These parameters and their meanings are subject to change
- ** without notice. These values are for testing purposes only.
- ** Applications should not use any of these parameters or the
- ** [sqlite3_test_control()] interface.
- */
- #define SQLITE_TESTCTRL_FIRST 5
- #define SQLITE_TESTCTRL_PRNG_SAVE 5
- #define SQLITE_TESTCTRL_PRNG_RESTORE 6
- #define SQLITE_TESTCTRL_PRNG_RESET 7
- #define SQLITE_TESTCTRL_BITVEC_TEST 8
- #define SQLITE_TESTCTRL_FAULT_INSTALL 9
- #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
- #define SQLITE_TESTCTRL_PENDING_BYTE 11
- #define SQLITE_TESTCTRL_ASSERT 12
- #define SQLITE_TESTCTRL_ALWAYS 13
- #define SQLITE_TESTCTRL_RESERVE 14
- #define SQLITE_TESTCTRL_OPTIMIZATIONS 15
- #define SQLITE_TESTCTRL_ISKEYWORD 16
- #define SQLITE_TESTCTRL_SCRATCHMALLOC 17
- #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
- #define SQLITE_TESTCTRL_EXPLAIN_STMT 19
- #define SQLITE_TESTCTRL_LAST 19
- /*
- ** CAPI3REF: SQLite Runtime Status
- **
- ** ^This interface is used to retrieve runtime status information
- ** about the performance of SQLite, and optionally to reset various
- ** highwater marks. ^The first argument is an integer code for
- ** the specific parameter to measure. ^(Recognized integer codes
- ** are of the form [status parameters | SQLITE_STATUS_...].)^
- ** ^The current value of the parameter is returned into *pCurrent.
- ** ^The highest recorded value is returned in *pHighwater. ^If the
- ** resetFlag is true, then the highest record value is reset after
- ** *pHighwater is written. ^(Some parameters do not record the highest
- ** value. For those parameters
- ** nothing is written into *pHighwater and the resetFlag is ignored.)^
- ** ^(Other parameters record only the highwater mark and not the current
- ** value. For these latter parameters nothing is written into *pCurrent.)^
- **
- ** ^The sqlite3_status() routine returns SQLITE_OK on success and a
- ** non-zero [error code] on failure.
- **
- ** This routine is threadsafe but is not atomic. This routine can be
- ** called while other threads are running the same or different SQLite
- ** interfaces. However the values returned in *pCurrent and
- ** *pHighwater reflect the status of SQLite at different points in time
- ** and it is possible that another thread might change the parameter
- ** in between the times when *pCurrent and *pHighwater are written.
- **
- ** See also: [sqlite3_db_status()]
- */
- SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
- /*
- ** CAPI3REF: Status Parameters
- ** KEYWORDS: {status parameters}
- **
- ** These integer constants designate various run-time status parameters
- ** that can be returned by [sqlite3_status()].
- **
- ** <dl>
- ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
- ** <dd>This parameter is the current amount of memory checked out
- ** using [sqlite3_malloc()], either directly or indirectly. The
- ** figure includes calls made to [sqlite3_malloc()] by the application
- ** and internal memory usage by the SQLite library. Scratch memory
- ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
- ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
- ** this parameter. The amount returned is the sum of the allocation
- ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
- **
- ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
- ** <dd>This parameter records the largest memory allocation request
- ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
- ** internal equivalents). Only the value returned in the
- ** *pHighwater parameter to [sqlite3_status()] is of interest.
- ** The value written into the *pCurrent parameter is undefined.</dd>)^
- **
- ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
- ** <dd>This parameter records the number of separate memory allocations
- ** currently checked out.</dd>)^
- **
- ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
- ** <dd>This parameter returns the number of pages used out of the
- ** [pagecache memory allocator] that was configured using
- ** [SQLITE_CONFIG_PAGECACHE]. The
- ** value returned is in pages, not in bytes.</dd>)^
- **
- ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
- ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
- ** <dd>This parameter returns the number of bytes of page cache
- ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
- ** buffer and where forced to overflow to [sqlite3_malloc()]. The
- ** returned value includes allocations that overflowed because they
- ** where too large (they were larger than the "sz" parameter to
- ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
- ** no space was left in the page cache.</dd>)^
- **
- ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
- ** <dd>This parameter records the largest memory allocation request
- ** handed to [pagecache memory allocator]. Only the value returned in the
- ** *pHighwater parameter to [sqlite3_status()] is of interest.
- ** The value written into the *pCurrent parameter is undefined.</dd>)^
- **
- ** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
- ** <dd>This parameter returns the number of allocations used out of the
- ** [scratch memory allocator] configured using
- ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
- ** in bytes. Since a single thread may only have one scratch allocation
- ** outstanding at time, this parameter also reports the number of threads
- ** using scratch memory at the same time.</dd>)^
- **
- ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
- ** <dd>This parameter returns the number of bytes of scratch memory
- ** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
- ** buffer and where forced to overflow to [sqlite3_malloc()]. The values
- ** returned include overflows because the requested allocation was too
- ** larger (that is, because the requested allocation was larger than the
- ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
- ** slots were available.
- ** </dd>)^
- **
- ** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
- ** <dd>This parameter records the largest memory allocation request
- ** handed to [scratch memory allocator]. Only the value returned in the
- ** *pHighwater parameter to [sqlite3_status()] is of interest.
- ** The value written into the *pCurrent parameter is undefined.</dd>)^
- **
- ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
- ** <dd>This parameter records the deepest parser stack. It is only
- ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
- ** </dl>
- **
- ** New status parameters may be added from time to time.
- */
- #define SQLITE_STATUS_MEMORY_USED 0
- #define SQLITE_STATUS_PAGECACHE_USED 1
- #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
- #define SQLITE_STATUS_SCRATCH_USED 3
- #define SQLITE_STATUS_SCRATCH_OVERFLOW 4
- #define SQLITE_STATUS_MALLOC_SIZE 5
- #define SQLITE_STATUS_PARSER_STACK 6
- #define SQLITE_STATUS_PAGECACHE_SIZE 7
- #define SQLITE_STATUS_SCRATCH_SIZE 8
- #define SQLITE_STATUS_MALLOC_COUNT 9
- /*
- ** CAPI3REF: Database Connection Status
- **
- ** ^This interface is used to retrieve runtime status information
- ** about a single [database connection]. ^The first argument is the
- ** database connection object to be interrogated. ^The second argument
- ** is an integer constant, taken from the set of
- ** [SQLITE_DBSTATUS options], that
- ** determines the parameter to interrogate. The set of
- ** [SQLITE_DBSTATUS options] is likely
- ** to grow in future releases of SQLite.
- **
- ** ^The current value of the requested parameter is written into *pCur
- ** and the highest instantaneous value is written into *pHiwtr. ^If
- ** the resetFlg is true, then the highest instantaneous value is
- ** reset back down to the current value.
- **
- ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
- ** non-zero [error code] on failure.
- **
- ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
- */
- SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
- /*
- ** CAPI3REF: Status Parameters for database connections
- ** KEYWORDS: {SQLITE_DBSTATUS options}
- **
- ** These constants are the available integer "verbs" that can be passed as
- ** the second argument to the [sqlite3_db_status()] interface.
- **
- ** New verbs may be added in future releases of SQLite. Existing verbs
- ** might be discontinued. Applications should check the return code from
- ** [sqlite3_db_status()] to make sure that the call worked.
- ** The [sqlite3_db_status()] interface will return a non-zero error code
- ** if a discontinued or unsupported verb is invoked.
- **
- ** <dl>
- ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
- ** <dd>This parameter returns the number of lookaside memory slots currently
- ** checked out.</dd>)^
- **
- ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
- ** <dd>This parameter returns the number malloc attempts that were
- ** satisfied using lookaside memory. Only the high-water value is meaningful;
- ** the current value is always zero.)^
- **
- ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
- ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
- ** <dd>This parameter returns the number malloc attempts that might have
- ** been satisfied using lookaside memory but failed due to the amount of
- ** memory requested being larger than the lookaside slot size.
- ** Only the high-water value is meaningful;
- ** the current value is always zero.)^
- **
- ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
- ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
- ** <dd>This parameter returns the number malloc attempts that might have
- ** been satisfied using lookaside memory but failed due to all lookaside
- ** memory already being in use.
- ** Only the high-water value is meaningful;
- ** the current value is always zero.)^
- **
- ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
- ** <dd>This parameter returns the approximate number of of bytes of heap
- ** memory used by all pager caches associated with the database connection.)^
- ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
- **
- ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
- ** <dd>This parameter returns the approximate number of of bytes of heap
- ** memory used to store the schema for all databases associated
- ** with the connection - main, temp, and any [ATTACH]-ed databases.)^
- ** ^The full amount of memory used by the schemas is reported, even if the
- ** schema memory is shared with other database connections due to
- ** [shared cache mode] being enabled.
- ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
- **
- ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
- ** <dd>This parameter returns the approximate number of of bytes of heap
- ** and lookaside memory used by all prepared statements associated with
- ** the database connection.)^
- ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
- ** </dd>
- **
- ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
- ** <dd>This parameter returns the number of pager cache hits that have
- ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
- ** is always 0.
- ** </dd>
- **
- ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
- ** <dd>This parameter returns the number of pager cache misses that have
- ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
- ** is always 0.
- ** </dd>
- ** </dl>
- */
- #define SQLITE_DBSTATUS_LOOKASIDE_USED 0
- #define SQLITE_DBSTATUS_CACHE_USED 1
- #define SQLITE_DBSTATUS_SCHEMA_USED 2
- #define SQLITE_DBSTATUS_STMT_USED 3
- #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
- #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
- #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
- #define SQLITE_DBSTATUS_CACHE_HIT 7
- #define SQLITE_DBSTATUS_CACHE_MISS 8
- #define SQLITE_DBSTATUS_MAX 8 /* Largest defined DBSTATUS */
- /*
- ** CAPI3REF: Prepared Statement Status
- **
- ** ^(Each prepared statement maintains various
- ** [SQLITE_STMTSTATUS counters] that measure the number
- ** of times it has performed specific operations.)^ These counters can
- ** be used to monitor the performance characteristics of the prepared
- ** statements. For example, if the number of table steps greatly exceeds
- ** the number of table searches or result rows, that would tend to indicate
- ** that the prepared statement is using a full table scan rather than
- ** an index.
- **
- ** ^(This interface is used to retrieve and reset counter values from
- ** a [prepared statement]. The first argument is the prepared statement
- ** object to be interrogated. The second argument
- ** is an integer code for a specific [SQLITE_STMTSTATUS counter]
- ** to be interrogated.)^
- ** ^The current value of the requested counter is returned.
- ** ^If the resetFlg is true, then the counter is reset to zero after this
- ** interface call returns.
- **
- ** See also: [sqlite3_status()] and [sqlite3_db_status()].
- */
- SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
- /*
- ** CAPI3REF: Status Parameters for prepared statements
- ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
- **
- ** These preprocessor macros define integer codes that name counter
- ** values associated with the [sqlite3_stmt_status()] interface.
- ** The meanings of the various counters are as follows:
- **
- ** <dl>
- ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
- ** <dd>^This is the number of times that SQLite has stepped forward in
- ** a table as part of a full table scan. Large numbers for this counter
- ** may indicate opportunities for performance improvement through
- ** careful use of indices.</dd>
- **
- ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
- ** <dd>^This is the number of sort operations that have occurred.
- ** A non-zero value in this counter may indicate an opportunity to
- ** improvement performance through careful use of indices.</dd>
- **
- ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
- ** <dd>^This is the number of rows inserted into transient indices that
- ** were created automatically in order to help joins run faster.
- ** A non-zero value in this counter may indicate an opportunity to
- ** improvement performance by adding permanent indices that do not
- ** need to be reinitialized each time the statement is run.</dd>
- ** </dl>
- */
- #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
- #define SQLITE_STMTSTATUS_SORT 2
- #define SQLITE_STMTSTATUS_AUTOINDEX 3
- /*
- ** CAPI3REF: Custom Page Cache Object
- **
- ** The sqlite3_pcache type is opaque. It is implemented by
- ** the pluggable module. The SQLite core has no knowledge of
- ** its size or internal structure and never deals with the
- ** sqlite3_pcache object except by holding and passing pointers
- ** to the object.
- **
- ** See [sqlite3_pcache_methods2] for additional information.
- */
- typedef struct sqlite3_pcache sqlite3_pcache;
- /*
- ** CAPI3REF: Custom Page Cache Object
- **
- ** The sqlite3_pcache_page object represents a single page in the
- ** page cache. The page cache will allocate instances of this
- ** object. Various methods of the page cache use pointers to instances
- ** of this object as parameters or as their return value.
- **
- ** See [sqlite3_pcache_methods2] for additional information.
- */
- typedef struct sqlite3_pcache_page sqlite3_pcache_page;
- struct sqlite3_pcache_page {
- void *pBuf; /* The content of the page */
- void *pExtra; /* Extra information associated with the page */
- };
- /*
- ** CAPI3REF: Application Defined Page Cache.
- ** KEYWORDS: {page cache}
- **
- ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
- ** register an alternative page cache implementation by passing in an
- ** instance of the sqlite3_pcache_methods2 structure.)^
- ** In many applications, most of the heap memory allocated by
- ** SQLite is used for the page cache.
- ** By implementing a
- ** custom page cache using this API, an application can better control
- ** the amount of memory consumed by SQLite, the way in which
- ** that memory is allocated and released, and the policies used to
- ** determine exactly which parts of a database file are cached and for
- ** how long.
- **
- ** The alternative page cache mechanism is an
- ** extreme measure that is only needed by the most demanding applications.
- ** The built-in page cache is recommended for most uses.
- **
- ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
- ** internal buffer by SQLite within the call to [sqlite3_config]. Hence
- ** the application may discard the parameter after the call to
- ** [sqlite3_config()] returns.)^
- **
- ** [[the xInit() page cache method]]
- ** ^(The xInit() method is called once for each effective
- ** call to [sqlite3_initialize()])^
- ** (usually only once during the lifetime of the process). ^(The xInit()
- ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
- ** The intent of the xInit() method is to set up global data structures
- ** required by the custom page cache implementation.
- ** ^(If the xInit() method is NULL, then the
- ** built-in default page cache is used instead of the application defined
- ** page cache.)^
- **
- ** [[the xShutdown() page cache method]]
- ** ^The xShutdown() method is called by [sqlite3_shutdown()].
- ** It can be used to clean up
- ** any outstanding resources before process shutdown, if required.
- ** ^The xShutdown() method may be NULL.
- **
- ** ^SQLite automatically serializes calls to the xInit method,
- ** so the xInit method need not be threadsafe. ^The
- ** xShutdown method is only called from [sqlite3_shutdown()] so it does
- ** not need to be threadsafe either. All other methods must be threadsafe
- ** in multithreaded applications.
- **
- ** ^SQLite will never invoke xInit() more than once without an intervening
- ** call to xShutdown().
- **
- ** [[the xCreate() page cache methods]]
- ** ^SQLite invokes the xCreate() method to construct a new cache instance.
- ** SQLite will typically create one cache instance for each open database file,
- ** though this is not guaranteed. ^The
- ** first parameter, szPage, is the size in bytes of the pages that must
- ** be allocated by the cache. ^szPage will always a power of two. ^The
- ** second parameter szExtra is a number of bytes of extra storage
- ** associated with each page cache entry. ^The szExtra parameter will
- ** a number less than 250. SQLite will use the
- ** extra szExtra bytes on each page to store metadata about the underlying
- ** database page on disk. The value passed into szExtra depends
- ** on the SQLite version, the target platform, and how SQLite was compiled.
- ** ^The third argument to xCreate(), bPurgeable, is true if the cache being
- ** created will be used to cache database pages of a file stored on disk, or
- ** false if it is used for an in-memory database. The cache implementation
- ** does not have to do anything special based with the value of bPurgeable;
- ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
- ** never invoke xUnpin() except to deliberately delete a page.
- ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
- ** false will always have the "discard" flag set to true.
- ** ^Hence, a cache created with bPurgeable false will
- ** never contain any unpinned pages.
- **
- ** [[the xCachesize() page cache method]]
- ** ^(The xCachesize() method may be called at any time by SQLite to set the
- ** suggested maximum cache-size (number of pages stored by) the cache
- ** instance passed as the first argument. This is the value configured using
- ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
- ** parameter, the implementation is not required to do anything with this
- ** value; it is advisory only.
- **
- ** [[the xPagecount() page cache methods]]
- ** The xPagecount() method must return the number of pages currently
- ** stored in the cache, both pinned and unpinned.
- **
- ** [[the xFetch() page cache methods]]
- ** The xFetch() method locates a page in the cache and returns a pointer to
- ** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
- ** The pBuf element of the returned sqlite3_pcache_page object will be a
- ** pointer to a buffer of szPage bytes used to store the content of a
- ** single database page. The pExtra element of sqlite3_pcache_page will be
- ** a pointer to the szExtra bytes of extra storage that SQLite has requested
- ** for each entry in the page cache.
- **
- ** The page to be fetched is determined by the key. ^The minimum key value
- ** is 1. After it has been retrieved using xFetch, the page is considered
- ** to be "pinned".
- **
- ** If the requested page is already in the page cache, then the page cache
- ** implementation must return a pointer to the page buffer with its content
- ** intact. If the requested page is not already in the cache, then the
- ** cache implementation should use the value of the createFlag
- ** parameter to help it determined what action to take:
- **
- ** <table border=1 width=85% align=center>
- ** <tr><th> createFlag <th> Behaviour when page is not already in cache
- ** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
- ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
- ** Otherwise return NULL.
- ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
- ** NULL if allocating a new page is effectively impossible.
- ** </table>
- **
- ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
- ** will only use a createFlag of 2 after a prior call with a createFlag of 1
- ** failed.)^ In between the to xFetch() calls, SQLite may
- ** attempt to unpin one or more cache pages by spilling the content of
- ** pinned pages to disk and synching the operating system disk cache.
- **
- ** [[the xUnpin() page cache method]]
- ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
- ** as its second argument. If the third parameter, discard, is non-zero,
- ** then the page must be evicted from the cache.
- ** ^If the discard parameter is
- ** zero, then the page may be discarded or retained at the discretion of
- ** page cache implementation. ^The page cache implementation
- ** may choose to evict unpinned pages at any time.
- **
- ** The cache must not perform any reference counting. A single
- ** call to xUnpin() unpins the page regardless of the number of prior calls
- ** to xFetch().
- **
- ** [[the xRekey() page cache methods]]
- ** The xRekey() method is used to change the key value associated with the
- ** page passed as the second argument. If the cache
- ** previously contains an entry associated with newKey, it must be
- ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
- ** to be pinned.
- **
- ** When SQLite calls the xTruncate() method, the cache must discard all
- ** existing cache entries with page numbers (keys) greater than or equal
- ** to the value of the iLimit parameter passed to xTruncate(). If any
- ** of these pages are pinned, they are implicitly unpinned, meaning that
- ** they can be safely discarded.
- **
- ** [[the xDestroy() page cache method]]
- ** ^The xDestroy() method is used to delete a cache allocated by xCreate().
- ** All resources associated with the specified cache should be freed. ^After
- ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
- ** handle invalid, and will not use it with any other sqlite3_pcache_methods2
- ** functions.
- **
- ** [[the xShrink() page cache method]]
- ** ^SQLite invokes the xShrink() method when it wants the page cache to
- ** free up as much of heap memory as possible. The page cache implementation
- ** is not obligated to free any memory, but well-behaved implementations should
- ** do their best.
- */
- typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
- struct sqlite3_pcache_methods2 {
- int iVersion;
- void *pArg;
- int (*xInit)(void*);
- void (*xShutdown)(void*);
- sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
- void (*xCachesize)(sqlite3_pcache*, int nCachesize);
- int (*xPagecount)(sqlite3_pcache*);
- sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
- void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
- void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
- unsigned oldKey, unsigned newKey);
- void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
- void (*xDestroy)(sqlite3_pcache*);
- void (*xShrink)(sqlite3_pcache*);
- };
- /*
- ** This is the obsolete pcache_methods object that has now been replaced
- ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
- ** retained in the header file for backwards compatibility only.
- */
- typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
- struct sqlite3_pcache_methods {
- void *pArg;
- int (*xInit)(void*);
- void (*xShutdown)(void*);
- sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
- void (*xCachesize)(sqlite3_pcache*, int nCachesize);
- int (*xPagecount)(sqlite3_pcache*);
- void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
- void (*xUnpin)(sqlite3_pcache*, void*, int discard);
- void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
- void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
- void (*xDestroy)(sqlite3_pcache*);
- };
- /*
- ** CAPI3REF: Online Backup Object
- **
- ** The sqlite3_backup object records state information about an ongoing
- ** online backup operation. ^The sqlite3_backup object is created by
- ** a call to [sqlite3_backup_init()] and is destroyed by a call to
- ** [sqlite3_backup_finish()].
- **
- ** See Also: [Using the SQLite Online Backup API]
- */
- typedef struct sqlite3_backup sqlite3_backup;
- /*
- ** CAPI3REF: Online Backup API.
- **
- ** The backup API copies the content of one database into another.
- ** It is useful either for creating backups of databases or
- ** for copying in-memory databases to or from persistent files.
- **
- ** See Also: [Using the SQLite Online Backup API]
- **
- ** ^SQLite holds a write transaction open on the destination database file
- ** for the duration of the backup operation.
- ** ^The source database is read-locked only while it is being read;
- ** it is not locked continuously for the entire backup operation.
- ** ^Thus, the backup may be performed on a live source database without
- ** preventing other database connections from
- ** reading or writing to the source database while the backup is underway.
- **
- ** ^(To perform a backup operation:
- ** <ol>
- ** <li><b>sqlite3_backup_init()</b> is called once to initialize the
- ** backup,
- ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
- ** the data between the two databases, and finally
- ** <li><b>sqlite3_backup_finish()</b> is called to release all resources
- ** associated with the backup operation.
- ** </ol>)^
- ** There should be exactly one call to sqlite3_backup_finish() for each
- ** successful call to sqlite3_backup_init().
- **
- ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
- **
- ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
- ** [database connection] associated with the destination database
- ** and the database name, respectively.
- ** ^The database name is "main" for the main database, "temp" for the
- ** temporary database, or the name specified after the AS keyword in
- ** an [ATTACH] statement for an attached database.
- ** ^The S and M arguments passed to
- ** sqlite3_backup_init(D,N,S,M) identify the [database connection]
- ** and database name of the source database, respectively.
- ** ^The source and destination [database connections] (parameters S and D)
- ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
- ** an error.
- **
- ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
- ** returned and an error code and error message are stored in the
- ** destination [database connection] D.
- ** ^The error code and message for the failed call to sqlite3_backup_init()
- ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
- ** [sqlite3_errmsg16()] functions.
- ** ^A successful call to sqlite3_backup_init() returns a pointer to an
- ** [sqlite3_backup] object.
- ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
- ** sqlite3_backup_finish() functions to perform the specified backup
- ** operation.
- **
- ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
- **
- ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
- ** the source and destination databases specified by [sqlite3_backup] object B.
- ** ^If N is negative, all remaining source pages are copied.
- ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
- ** are still more pages to be copied, then the function returns [SQLITE_OK].
- ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
- ** from source to destination, then it returns [SQLITE_DONE].
- ** ^If an error occurs while running sqlite3_backup_step(B,N),
- ** then an [error code] is returned. ^As well as [SQLITE_OK] and
- ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
- ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
- ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
- **
- ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
- ** <ol>
- ** <li> the destination database was opened read-only, or
- ** <li> the destination database is using write-ahead-log journaling
- ** and the destination and source page sizes differ, or
- ** <li> the destination database is an in-memory database and the
- ** destination and source page sizes differ.
- ** </ol>)^
- **
- ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
- ** the [sqlite3_busy_handler | busy-handler function]
- ** is invoked (if one is specified). ^If the
- ** busy-handler returns non-zero before the lock is available, then
- ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
- ** sqlite3_backup_step() can be retried later. ^If the source
- ** [database connection]
- ** is being used to write to the source database when sqlite3_backup_step()
- ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
- ** case the call to sqlite3_backup_step() can be retried later on. ^(If
- ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
- ** [SQLITE_READONLY] is returned, then
- ** there is no point in retrying the call to sqlite3_backup_step(). These
- ** errors are considered fatal.)^ The application must accept
- ** that the backup operation has failed and pass the backup operation handle
- ** to the sqlite3_backup_finish() to release associated resources.
- **
- ** ^The first call to sqlite3_backup_step() obtains an exclusive lock
- ** on the destination file. ^The exclusive lock is not released until either
- ** sqlite3_backup_finish() is called or the backup operation is complete
- ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
- ** sqlite3_backup_step() obtains a [shared lock] on the source database that
- ** lasts for the duration of the sqlite3_backup_step() call.
- ** ^Because the source database is not locked between calls to
- ** sqlite3_backup_step(), the source database may be modified mid-way
- ** through the backup process. ^If the source database is modified by an
- ** external process or via a database connection other than the one being
- ** used by the backup operation, then the backup will be automatically
- ** restarted by the next call to sqlite3_backup_step(). ^If the source
- ** database is modified by the using the same database connection as is used
- ** by the backup operation, then the backup database is automatically
- ** updated at the same time.
- **
- ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
- **
- ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
- ** application wishes to abandon the backup operation, the application
- ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
- ** ^The sqlite3_backup_finish() interfaces releases all
- ** resources associated with the [sqlite3_backup] object.
- ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
- ** active write-transaction on the destination database is rolled back.
- ** The [sqlite3_backup] object is invalid
- ** and may not be used following a call to sqlite3_backup_finish().
- **
- ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
- ** sqlite3_backup_step() errors occurred, regardless or whether or not
- ** sqlite3_backup_step() completed.
- ** ^If an out-of-memory condition or IO error occurred during any prior
- ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
- ** sqlite3_backup_finish() returns the corresponding [error code].
- **
- ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
- ** is not a permanent error and does not affect the return value of
- ** sqlite3_backup_finish().
- **
- ** [[sqlite3_backup__remaining()]] [[sqlite3_backup_pagecount()]]
- ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
- **
- ** ^Each call to sqlite3_backup_step() sets two values inside
- ** the [sqlite3_backup] object: the number of pages still to be backed
- ** up and the total number of pages in the source database file.
- ** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
- ** retrieve these two values, respectively.
- **
- ** ^The values returned by these functions are only updated by
- ** sqlite3_backup_step(). ^If the source database is modified during a backup
- ** operation, then the values are not updated to account for any extra
- ** pages that need to be updated or the size of the source database file
- ** changing.
- **
- ** <b>Concurrent Usage of Database Handles</b>
- **
- ** ^The source [database connection] may be used by the application for other
- ** purposes while a backup operation is underway or being initialized.
- ** ^If SQLite is compiled and configured to support threadsafe database
- ** connections, then the source database connection may be used concurrently
- ** from within other threads.
- **
- ** However, the application must guarantee that the destination
- ** [database connection] is not passed to any other API (by any thread) after
- ** sqlite3_backup_init() is called and before the corresponding call to
- ** sqlite3_backup_finish(). SQLite does not currently check to see
- ** if the application incorrectly accesses the destination [database connection]
- ** and so no error code is reported, but the operations may malfunction
- ** nevertheless. Use of the destination database connection while a
- ** backup is in progress might also also cause a mutex deadlock.
- **
- ** If running in [shared cache mode], the application must
- ** guarantee that the shared cache used by the destination database
- ** is not accessed while the backup is running. In practice this means
- ** that the application must guarantee that the disk file being
- ** backed up to is not accessed by any connection within the process,
- ** not just the specific connection that was passed to sqlite3_backup_init().
- **
- ** The [sqlite3_backup] object itself is partially threadsafe. Multiple
- ** threads may safely make multiple concurrent calls to sqlite3_backup_step().
- ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
- ** APIs are not strictly speaking threadsafe. If they are invoked at the
- ** same time as another thread is invoking sqlite3_backup_step() it is
- ** possible that they return invalid values.
- */
- SQLITE_API sqlite3_backup *sqlite3_backup_init(
- sqlite3 *pDest, /* Destination database handle */
- const char *zDestName, /* Destination database name */
- sqlite3 *pSource, /* Source database handle */
- const char *zSourceName /* Source database name */
- );
- SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
- SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
- SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
- SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
- /*
- ** CAPI3REF: Unlock Notification
- **
- ** ^When running in shared-cache mode, a database operation may fail with
- ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
- ** individual tables within the shared-cache cannot be obtained. See
- ** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
- ** ^This API may be used to register a callback that SQLite will invoke
- ** when the connection currently holding the required lock relinquishes it.
- ** ^This API is only available if the library was compiled with the
- ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
- **
- ** See Also: [Using the SQLite Unlock Notification Feature].
- **
- ** ^Shared-cache locks are released when a database connection concludes
- ** its current transaction, either by committing it or rolling it back.
- **
- ** ^When a connection (known as the blocked connection) fails to obtain a
- ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
- ** identity of the database connection (the blocking connection) that
- ** has locked the required resource is stored internally. ^After an
- ** application receives an SQLITE_LOCKED error, it may call the
- ** sqlite3_unlock_notify() method with the blocked connection handle as
- ** the first argument to register for a callback that will be invoked
- ** when the blocking connections current transaction is concluded. ^The
- ** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
- ** call that concludes the blocking connections transaction.
- **
- ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
- ** there is a chance that the blocking connection will have already
- ** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
- ** If this happens, then the specified callback is invoked immediately,
- ** from within the call to sqlite3_unlock_notify().)^
- **
- ** ^If the blocked connection is attempting to obtain a write-lock on a
- ** shared-cache table, and more than one other connection currently holds
- ** a read-lock on the same table, then SQLite arbitrarily selects one of
- ** the other connections to use as the blocking connection.
- **
- ** ^(There may be at most one unlock-notify callback registered by a
- ** blocked connection. If sqlite3_unlock_notify() is called when the
- ** blocked connection already has a registered unlock-notify callback,
- ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
- ** called with a NULL pointer as its second argument, then any existing
- ** unlock-notify callback is canceled. ^The blocked connections
- ** unlock-notify callback may also be canceled by closing the blocked
- ** connection using [sqlite3_close()].
- **
- ** The unlock-notify callback is not reentrant. If an application invokes
- ** any sqlite3_xxx API functions from within an unlock-notify callback, a
- ** crash or deadlock may be the result.
- **
- ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
- ** returns SQLITE_OK.
- **
- ** <b>Callback Invocation Details</b>
- **
- ** When an unlock-notify callback is registered, the application provides a
- ** single void* pointer that is passed to the callback when it is invoked.
- ** However, the signature of the callback function allows SQLite to pass
- ** it an array of void* context pointers. The first argument passed to
- ** an unlock-notify callback is a pointer to an array of void* pointers,
- ** and the second is the number of entries in the array.
- **
- ** When a blocking connections transaction is concluded, there may be
- ** more than one blocked connection that has registered for an unlock-notify
- ** callback. ^If two or more such blocked connections have specified the
- ** same callback function, then instead of invoking the callback function
- ** multiple times, it is invoked once with the set of void* context pointers
- ** specified by the blocked connections bundled together into an array.
- ** This gives the application an opportunity to prioritize any actions
- ** related to the set of unblocked database connections.
- **
- ** <b>Deadlock Detection</b>
- **
- ** Assuming that after registering for an unlock-notify callback a
- ** database waits for the callback to be issued before taking any further
- ** action (a reasonable assumption), then using this API may cause the
- ** application to deadlock. For example, if connection X is waiting for
- ** connection Y's transaction to be concluded, and similarly connection
- ** Y is waiting on connection X's transaction, then neither connection
- ** will proceed and the system may remain deadlocked indefinitely.
- **
- ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
- ** detection. ^If a given call to sqlite3_unlock_notify() would put the
- ** system in a deadlocked state, then SQLITE_LOCKED is returned and no
- ** unlock-notify callback is registered. The system is said to be in
- ** a deadlocked state if connection A has registered for an unlock-notify
- ** callback on the conclusion of connection B's transaction, and connection
- ** B has itself registered for an unlock-notify callback when connection
- ** A's transaction is concluded. ^Indirect deadlock is also detected, so
- ** the system is also considered to be deadlocked if connection B has
- ** registered for an unlock-notify callback on the conclusion of connection
- ** C's transaction, where connection C is waiting on connection A. ^Any
- ** number of levels of indirection are allowed.
- **
- ** <b>The "DROP TABLE" Exception</b>
- **
- ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
- ** always appropriate to call sqlite3_unlock_notify(). There is however,
- ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
- ** SQLite checks if there are any currently executing SELECT statements
- ** that belong to the same connection. If there are, SQLITE_LOCKED is
- ** returned. In this case there is no "blocking connection", so invoking
- ** sqlite3_unlock_notify() results in the unlock-notify callback being
- ** invoked immediately. If the application then re-attempts the "DROP TABLE"
- ** or "DROP INDEX" query, an infinite loop might be the result.
- **
- ** One way around this problem is to check the extended error code returned
- ** by an sqlite3_step() call. ^(If there is a blocking connection, then the
- ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
- ** the special "DROP TABLE/INDEX" case, the extended error code is just
- ** SQLITE_LOCKED.)^
- */
- SQLITE_API int sqlite3_unlock_notify(
- sqlite3 *pBlocked, /* Waiting connection */
- void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
- void *pNotifyArg /* Argument to pass to xNotify */
- );
- /*
- ** CAPI3REF: String Comparison
- **
- ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
- ** and extensions to compare the contents of two buffers containing UTF-8
- ** strings in a case-independent fashion, using the same definition of "case
- ** independence" that SQLite uses internally when comparing identifiers.
- */
- SQLITE_API int sqlite3_stricmp(const char *, const char *);
- SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
- /*
- ** CAPI3REF: Error Logging Interface
- **
- ** ^The [sqlite3_log()] interface writes a message into the error log
- ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
- ** ^If logging is enabled, the zFormat string and subsequent arguments are
- ** used with [sqlite3_snprintf()] to generate the final output string.
- **
- ** The sqlite3_log() interface is intended for use by extensions such as
- ** virtual tables, collating functions, and SQL functions. While there is
- ** nothing to prevent an application from calling sqlite3_log(), doing so
- ** is considered bad form.
- **
- ** The zFormat string must not be NULL.
- **
- ** To avoid deadlocks and other threading problems, the sqlite3_log() routine
- ** will not use dynamically allocated memory. The log message is stored in
- ** a fixed-length buffer on the stack. If the log message is longer than
- ** a few hundred characters, it will be truncated to the length of the
- ** buffer.
- */
- SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
- /*
- ** CAPI3REF: Write-Ahead Log Commit Hook
- **
- ** ^The [sqlite3_wal_hook()] function is used to register a callback that
- ** will be invoked each time a database connection commits data to a
- ** [write-ahead log] (i.e. whenever a transaction is committed in
- ** [journal_mode | journal_mode=WAL mode]).
- **
- ** ^The callback is invoked by SQLite after the commit has taken place and
- ** the associated write-lock on the database released, so the implementation
- ** may read, write or [checkpoint] the database as required.
- **
- ** ^The first parameter passed to the callback function when it is invoked
- ** is a copy of the third parameter passed to sqlite3_wal_hook() when
- ** registering the callback. ^The second is a copy of the database handle.
- ** ^The third parameter is the name of the database that was written to -
- ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
- ** is the number of pages currently in the write-ahead log file,
- ** including those that were just committed.
- **
- ** The callback function should normally return [SQLITE_OK]. ^If an error
- ** code is returned, that error will propagate back up through the
- ** SQLite code base to cause the statement that provoked the callback
- ** to report an error, though the commit will have still occurred. If the
- ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
- ** that does not correspond to any valid SQLite error code, the results
- ** are undefined.
- **
- ** A single database handle may have at most a single write-ahead log callback
- ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
- ** previously registered write-ahead log callback. ^Note that the
- ** [sqlite3_wal_autocheckpoint()] interface and the
- ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
- ** those overwrite any prior [sqlite3_wal_hook()] settings.
- */
- SQLITE_API void *sqlite3_wal_hook(
- sqlite3*,
- int(*)(void *,sqlite3*,const char*,int),
- void*
- );
- /*
- ** CAPI3REF: Configure an auto-checkpoint
- **
- ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
- ** [sqlite3_wal_hook()] that causes any database on [database connection] D
- ** to automatically [checkpoint]
- ** after committing a transaction if there are N or
- ** more frames in the [write-ahead log] file. ^Passing zero or
- ** a negative value as the nFrame parameter disables automatic
- ** checkpoints entirely.
- **
- ** ^The callback registered by this function replaces any existing callback
- ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
- ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
- ** configured by this function.
- **
- ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
- ** from SQL.
- **
- ** ^Every new [database connection] defaults to having the auto-checkpoint
- ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
- ** pages. The use of this interface
- ** is only necessary if the default setting is found to be suboptimal
- ** for a particular application.
- */
- SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
- /*
- ** CAPI3REF: Checkpoint a database
- **
- ** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
- ** on [database connection] D to be [checkpointed]. ^If X is NULL or an
- ** empty string, then a checkpoint is run on all databases of
- ** connection D. ^If the database connection D is not in
- ** [WAL | write-ahead log mode] then this interface is a harmless no-op.
- **
- ** ^The [wal_checkpoint pragma] can be used to invoke this interface
- ** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the
- ** [wal_autocheckpoint pragma] can be used to cause this interface to be
- ** run whenever the WAL reaches a certain size threshold.
- **
- ** See also: [sqlite3_wal_checkpoint_v2()]
- */
- SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
- /*
- ** CAPI3REF: Checkpoint a database
- **
- ** Run a checkpoint operation on WAL database zDb attached to database
- ** handle db. The specific operation is determined by the value of the
- ** eMode parameter:
- **
- ** <dl>
- ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
- ** Checkpoint as many frames as possible without waiting for any database
- ** readers or writers to finish. Sync the db file if all frames in the log
- ** are checkpointed. This mode is the same as calling
- ** sqlite3_wal_checkpoint(). The busy-handler callback is never invoked.
- **
- ** <dt>SQLITE_CHECKPOINT_FULL<dd>
- ** This mode blocks (calls the busy-handler callback) until there is no
- ** database writer and all readers are reading from the most recent database
- ** snapshot. It then checkpoints all frames in the log file and syncs the
- ** database file. This call blocks database writers while it is running,
- ** but not database readers.
- **
- ** <dt>SQLITE_CHECKPOINT_RESTART<dd>
- ** This mode works the same way as SQLITE_CHECKPOINT_FULL, except after
- ** checkpointing the log file it blocks (calls the busy-handler callback)
- ** until all readers are reading from the database file only. This ensures
- ** that the next client to write to the database file restarts the log file
- ** from the beginning. This call blocks database writers while it is running,
- ** but not database readers.
- ** </dl>
- **
- ** If pnLog is not NULL, then *pnLog is set to the total number of frames in
- ** the log file before returning. If pnCkpt is not NULL, then *pnCkpt is set to
- ** the total number of checkpointed frames (including any that were already
- ** checkpointed when this function is called). *pnLog and *pnCkpt may be
- ** populated even if sqlite3_wal_checkpoint_v2() returns other than SQLITE_OK.
- ** If no values are available because of an error, they are both set to -1
- ** before returning to communicate this to the caller.
- **
- ** All calls obtain an exclusive "checkpoint" lock on the database file. If
- ** any other process is running a checkpoint operation at the same time, the
- ** lock cannot be obtained and SQLITE_BUSY is returned. Even if there is a
- ** busy-handler configured, it will not be invoked in this case.
- **
- ** The SQLITE_CHECKPOINT_FULL and RESTART modes also obtain the exclusive
- ** "writer" lock on the database file. If the writer lock cannot be obtained
- ** immediately, and a busy-handler is configured, it is invoked and the writer
- ** lock retried until either the busy-handler returns 0 or the lock is
- ** successfully obtained. The busy-handler is also invoked while waiting for
- ** database readers as described above. If the busy-handler returns 0 before
- ** the writer lock is obtained or while waiting for database readers, the
- ** checkpoint operation proceeds from that point in the same way as
- ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
- ** without blocking any further. SQLITE_BUSY is returned in this case.
- **
- ** If parameter zDb is NULL or points to a zero length string, then the
- ** specified operation is attempted on all WAL databases. In this case the
- ** values written to output parameters *pnLog and *pnCkpt are undefined. If
- ** an SQLITE_BUSY error is encountered when processing one or more of the
- ** attached WAL databases, the operation is still attempted on any remaining
- ** attached databases and SQLITE_BUSY is returned to the caller. If any other
- ** error occurs while processing an attached database, processing is abandoned
- ** and the error code returned to the caller immediately. If no error
- ** (SQLITE_BUSY or otherwise) is encountered while processing the attached
- ** databases, SQLITE_OK is returned.
- **
- ** If database zDb is the name of an attached database that is not in WAL
- ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. If
- ** zDb is not NULL (or a zero length string) and is not the name of any
- ** attached database, SQLITE_ERROR is returned to the caller.
- */
- SQLITE_API int sqlite3_wal_checkpoint_v2(
- sqlite3 *db, /* Database handle */
- const char *zDb, /* Name of attached database (or NULL) */
- int eMode, /* SQLITE_CHECKPOINT_* value */
- int *pnLog, /* OUT: Size of WAL log in frames */
- int *pnCkpt /* OUT: Total number of frames checkpointed */
- );
- /*
- ** CAPI3REF: Checkpoint operation parameters
- **
- ** These constants can be used as the 3rd parameter to
- ** [sqlite3_wal_checkpoint_v2()]. See the [sqlite3_wal_checkpoint_v2()]
- ** documentation for additional information about the meaning and use of
- ** each of these values.
- */
- #define SQLITE_CHECKPOINT_PASSIVE 0
- #define SQLITE_CHECKPOINT_FULL 1
- #define SQLITE_CHECKPOINT_RESTART 2
- /*
- ** CAPI3REF: Virtual Table Interface Configuration
- **
- ** This function may be called by either the [xConnect] or [xCreate] method
- ** of a [virtual table] implementation to configure
- ** various facets of the virtual table interface.
- **
- ** If this interface is invoked outside the context of an xConnect or
- ** xCreate virtual table method then the behavior is undefined.
- **
- ** At present, there is only one option that may be configured using
- ** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options
- ** may be added in the future.
- */
- SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
- /*
- ** CAPI3REF: Virtual Table Configuration Options
- **
- ** These macros define the various options to the
- ** [sqlite3_vtab_config()] interface that [virtual table] implementations
- ** can use to customize and optimize their behavior.
- **
- ** <dl>
- ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT
- ** <dd>Calls of the form
- ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
- ** where X is an integer. If X is zero, then the [virtual table] whose
- ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
- ** support constraints. In this configuration (which is the default) if
- ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
- ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
- ** specified as part of the users SQL statement, regardless of the actual
- ** ON CONFLICT mode specified.
- **
- ** If X is non-zero, then the virtual table implementation guarantees
- ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
- ** any modifications to internal or persistent data structures have been made.
- ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
- ** is able to roll back a statement or database transaction, and abandon
- ** or continue processing the current SQL statement as appropriate.
- ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
- ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
- ** had been ABORT.
- **
- ** Virtual table implementations that are required to handle OR REPLACE
- ** must do so within the [xUpdate] method. If a call to the
- ** [sqlite3_vtab_on_conflict()] function indicates that the current ON
- ** CONFLICT policy is REPLACE, the virtual table implementation should
- ** silently replace the appropriate rows within the xUpdate callback and
- ** return SQLITE_OK. Or, if this is not possible, it may return
- ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
- ** constraint handling.
- ** </dl>
- */
- #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
- /*
- ** CAPI3REF: Determine The Virtual Table Conflict Policy
- **
- ** This function may only be called from within a call to the [xUpdate] method
- ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
- ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
- ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
- ** of the SQL statement that triggered the call to the [xUpdate] method of the
- ** [virtual table].
- */
- SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
- /*
- ** CAPI3REF: Conflict resolution modes
- **
- ** These constants are returned by [sqlite3_vtab_on_conflict()] to
- ** inform a [virtual table] implementation what the [ON CONFLICT] mode
- ** is for the SQL statement being evaluated.
- **
- ** Note that the [SQLITE_IGNORE] constant is also used as a potential
- ** return value from the [sqlite3_set_authorizer()] callback and that
- ** [SQLITE_ABORT] is also a [result code].
- */
- #define SQLITE_ROLLBACK 1
- /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
- #define SQLITE_FAIL 3
- /* #define SQLITE_ABORT 4 // Also an error code */
- #define SQLITE_REPLACE 5
- /*
- ** Undo the hack that converts floating point types to integer for
- ** builds on processors without floating point support.
- */
- #ifdef SQLITE_OMIT_FLOATING_POINT
- # undef double
- #endif
- #if 0
- } /* End of the 'extern "C"' block */
- #endif
- #endif
- /*
- ** 2010 August 30
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- */
- #ifndef _SQLITE3RTREE_H_
- #define _SQLITE3RTREE_H_
- #if 0
- extern "C" {
- #endif
- typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
- /*
- ** Register a geometry callback named zGeom that can be used as part of an
- ** R-Tree geometry query as follows:
- **
- ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
- */
- SQLITE_API int sqlite3_rtree_geometry_callback(
- sqlite3 *db,
- const char *zGeom,
- int (*xGeom)(sqlite3_rtree_geometry *, int nCoord, double *aCoord, int *pRes),
- void *pContext
- );
- /*
- ** A pointer to a structure of the following type is passed as the first
- ** argument to callbacks registered using rtree_geometry_callback().
- */
- struct sqlite3_rtree_geometry {
- void *pContext; /* Copy of pContext passed to s_r_g_c() */
- int nParam; /* Size of array aParam[] */
- double *aParam; /* Parameters passed to SQL geom function */
- void *pUser; /* Callback implementation user data */
- void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
- };
- #if 0
- } /* end of the 'extern "C"' block */
- #endif
- #endif /* ifndef _SQLITE3RTREE_H_ */
- /************** End of sqlite3.h *********************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /************** Include hash.h in the middle of sqliteInt.h ******************/
- /************** Begin file hash.h ********************************************/
- /*
- ** 2001 September 22
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- ** This is the header file for the generic hash-table implemenation
- ** used in SQLite.
- */
- #ifndef _SQLITE_HASH_H_
- #define _SQLITE_HASH_H_
- /* Forward declarations of structures. */
- typedef struct Hash Hash;
- typedef struct HashElem HashElem;
- /* A complete hash table is an instance of the following structure.
- ** The internals of this structure are intended to be opaque -- client
- ** code should not attempt to access or modify the fields of this structure
- ** directly. Change this structure only by using the routines below.
- ** However, some of the "procedures" and "functions" for modifying and
- ** accessing this structure are really macros, so we can't really make
- ** this structure opaque.
- **
- ** All elements of the hash table are on a single doubly-linked list.
- ** Hash.first points to the head of this list.
- **
- ** There are Hash.htsize buckets. Each bucket points to a spot in
- ** the global doubly-linked list. The contents of the bucket are the
- ** element pointed to plus the next _ht.count-1 elements in the list.
- **
- ** Hash.htsize and Hash.ht may be zero. In that case lookup is done
- ** by a linear search of the global list. For small tables, the
- ** Hash.ht table is never allocated because if there are few elements
- ** in the table, it is faster to do a linear search than to manage
- ** the hash table.
- */
- struct Hash {
- unsigned int htsize; /* Number of buckets in the hash table */
- unsigned int count; /* Number of entries in this table */
- HashElem *first; /* The first element of the array */
- struct _ht { /* the hash table */
- int count; /* Number of entries with this hash */
- HashElem *chain; /* Pointer to first entry with this hash */
- } *ht;
- };
- /* Each element in the hash table is an instance of the following
- ** structure. All elements are stored on a single doubly-linked list.
- **
- ** Again, this structure is intended to be opaque, but it can't really
- ** be opaque because it is used by macros.
- */
- struct HashElem {
- HashElem *next, *prev; /* Next and previous elements in the table */
- void *data; /* Data associated with this element */
- const char *pKey; int nKey; /* Key associated with this element */
- };
- /*
- ** Access routines. To delete, insert a NULL pointer.
- */
- SQLITE_PRIVATE void sqlite3HashInit(Hash*);
- SQLITE_PRIVATE void *sqlite3HashInsert(Hash*, const char *pKey, int nKey, void *pData);
- SQLITE_PRIVATE void *sqlite3HashFind(const Hash*, const char *pKey, int nKey);
- SQLITE_PRIVATE void sqlite3HashClear(Hash*);
- /*
- ** Macros for looping over all elements of a hash table. The idiom is
- ** like this:
- **
- ** Hash h;
- ** HashElem *p;
- ** ...
- ** for(p=sqliteHashFirst(&h); p; p=sqliteHashNext(p)){
- ** SomeStructure *pData = sqliteHashData(p);
- ** // do something with pData
- ** }
- */
- #define sqliteHashFirst(H) ((H)->first)
- #define sqliteHashNext(E) ((E)->next)
- #define sqliteHashData(E) ((E)->data)
- /* #define sqliteHashKey(E) ((E)->pKey) // NOT USED */
- /* #define sqliteHashKeysize(E) ((E)->nKey) // NOT USED */
- /*
- ** Number of entries in a hash table
- */
- /* #define sqliteHashCount(H) ((H)->count) // NOT USED */
- #endif /* _SQLITE_HASH_H_ */
- /************** End of hash.h ************************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /************** Include parse.h in the middle of sqliteInt.h *****************/
- /************** Begin file parse.h *******************************************/
- #define TK_SEMI 1
- #define TK_EXPLAIN 2
- #define TK_QUERY 3
- #define TK_PLAN 4
- #define TK_BEGIN 5
- #define TK_TRANSACTION 6
- #define TK_DEFERRED 7
- #define TK_IMMEDIATE 8
- #define TK_EXCLUSIVE 9
- #define TK_COMMIT 10
- #define TK_END 11
- #define TK_ROLLBACK 12
- #define TK_SAVEPOINT 13
- #define TK_RELEASE 14
- #define TK_TO 15
- #define TK_TABLE 16
- #define TK_CREATE 17
- #define TK_IF 18
- #define TK_NOT 19
- #define TK_EXISTS 20
- #define TK_TEMP 21
- #define TK_LP 22
- #define TK_RP 23
- #define TK_AS 24
- #define TK_COMMA 25
- #define TK_ID 26
- #define TK_INDEXED 27
- #define TK_ABORT 28
- #define TK_ACTION 29
- #define TK_AFTER 30
- #define TK_ANALYZE 31
- #define TK_ASC 32
- #define TK_ATTACH 33
- #define TK_BEFORE 34
- #define TK_BY 35
- #define TK_CASCADE 36
- #define TK_CAST 37
- #define TK_COLUMNKW 38
- #define TK_CONFLICT 39
- #define TK_DATABASE 40
- #define TK_DESC 41
- #define TK_DETACH 42
- #define TK_EACH 43
- #define TK_FAIL 44
- #define TK_FOR 45
- #define TK_IGNORE 46
- #define TK_INITIALLY 47
- #define TK_INSTEAD 48
- #define TK_LIKE_KW 49
- #define TK_MATCH 50
- #define TK_NO 51
- #define TK_KEY 52
- #define TK_OF 53
- #define TK_OFFSET 54
- #define TK_PRAGMA 55
- #define TK_RAISE 56
- #define TK_REPLACE 57
- #define TK_RESTRICT 58
- #define TK_ROW 59
- #define TK_TRIGGER 60
- #define TK_VACUUM 61
- #define TK_VIEW 62
- #define TK_VIRTUAL 63
- #define TK_REINDEX 64
- #define TK_RENAME 65
- #define TK_CTIME_KW 66
- #define TK_ANY 67
- #define TK_OR 68
- #define TK_AND 69
- #define TK_IS 70
- #define TK_BETWEEN 71
- #define TK_IN 72
- #define TK_ISNULL 73
- #define TK_NOTNULL 74
- #define TK_NE 75
- #define TK_EQ 76
- #define TK_GT 77
- #define TK_LE 78
- #define TK_LT 79
- #define TK_GE 80
- #define TK_ESCAPE 81
- #define TK_BITAND 82
- #define TK_BITOR 83
- #define TK_LSHIFT 84
- #define TK_RSHIFT 85
- #define TK_PLUS 86
- #define TK_MINUS 87
- #define TK_STAR 88
- #define TK_SLASH 89
- #define TK_REM 90
- #define TK_CONCAT 91
- #define TK_COLLATE 92
- #define TK_BITNOT 93
- #define TK_STRING 94
- #define TK_JOIN_KW 95
- #define TK_CONSTRAINT 96
- #define TK_DEFAULT 97
- #define TK_NULL 98
- #define TK_PRIMARY 99
- #define TK_UNIQUE 100
- #define TK_CHECK 101
- #define TK_REFERENCES 102
- #define TK_AUTOINCR 103
- #define TK_ON 104
- #define TK_INSERT 105
- #define TK_DELETE 106
- #define TK_UPDATE 107
- #define TK_SET 108
- #define TK_DEFERRABLE 109
- #define TK_FOREIGN 110
- #define TK_DROP 111
- #define TK_UNION 112
- #define TK_ALL 113
- #define TK_EXCEPT 114
- #define TK_INTERSECT 115
- #define TK_SELECT 116
- #define TK_DISTINCT 117
- #define TK_DOT 118
- #define TK_FROM 119
- #define TK_JOIN 120
- #define TK_USING 121
- #define TK_ORDER 122
- #define TK_GROUP 123
- #define TK_HAVING 124
- #define TK_LIMIT 125
- #define TK_WHERE 126
- #define TK_INTO 127
- #define TK_VALUES 128
- #define TK_INTEGER 129
- #define TK_FLOAT 130
- #define TK_BLOB 131
- #define TK_REGISTER 132
- #define TK_VARIABLE 133
- #define TK_CASE 134
- #define TK_WHEN 135
- #define TK_THEN 136
- #define TK_ELSE 137
- #define TK_INDEX 138
- #define TK_ALTER 139
- #define TK_ADD 140
- #define TK_TO_TEXT 141
- #define TK_TO_BLOB 142
- #define TK_TO_NUMERIC 143
- #define TK_TO_INT 144
- #define TK_TO_REAL 145
- #define TK_ISNOT 146
- #define TK_END_OF_FILE 147
- #define TK_ILLEGAL 148
- #define TK_SPACE 149
- #define TK_UNCLOSED_STRING 150
- #define TK_FUNCTION 151
- #define TK_COLUMN 152
- #define TK_AGG_FUNCTION 153
- #define TK_AGG_COLUMN 154
- #define TK_CONST_FUNC 155
- #define TK_UMINUS 156
- #define TK_UPLUS 157
- /************** End of parse.h ***********************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <assert.h>
- #include <stddef.h>
- /*
- ** If compiling for a processor that lacks floating point support,
- ** substitute integer for floating-point
- */
- #ifdef SQLITE_OMIT_FLOATING_POINT
- # define double sqlite_int64
- # define float sqlite_int64
- # define LONGDOUBLE_TYPE sqlite_int64
- # ifndef SQLITE_BIG_DBL
- # define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
- # endif
- # define SQLITE_OMIT_DATETIME_FUNCS 1
- # define SQLITE_OMIT_TRACE 1
- # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
- # undef SQLITE_HAVE_ISNAN
- #endif
- #ifndef SQLITE_BIG_DBL
- # define SQLITE_BIG_DBL (1e99)
- #endif
- /*
- ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
- ** afterward. Having this macro allows us to cause the C compiler
- ** to omit code used by TEMP tables without messy #ifndef statements.
- */
- #ifdef SQLITE_OMIT_TEMPDB
- #define OMIT_TEMPDB 1
- #else
- #define OMIT_TEMPDB 0
- #endif
- /*
- ** The "file format" number is an integer that is incremented whenever
- ** the VDBE-level file format changes. The following macros define the
- ** the default file format for new databases and the maximum file format
- ** that the library can read.
- */
- #define SQLITE_MAX_FILE_FORMAT 4
- #ifndef SQLITE_DEFAULT_FILE_FORMAT
- # define SQLITE_DEFAULT_FILE_FORMAT 4
- #endif
- /*
- ** Determine whether triggers are recursive by default. This can be
- ** changed at run-time using a pragma.
- */
- #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
- # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
- #endif
- /*
- ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
- ** on the command-line
- */
- #ifndef SQLITE_TEMP_STORE
- # define SQLITE_TEMP_STORE 1
- #endif
- /*
- ** GCC does not define the offsetof() macro so we'll have to do it
- ** ourselves.
- */
- #ifndef offsetof
- #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
- #endif
- /*
- ** Check to see if this machine uses EBCDIC. (Yes, believe it or
- ** not, there are still machines out there that use EBCDIC.)
- */
- #if 'A' == '\301'
- # define SQLITE_EBCDIC 1
- #else
- # define SQLITE_ASCII 1
- #endif
- /*
- ** Integers of known sizes. These typedefs might change for architectures
- ** where the sizes very. Preprocessor macros are available so that the
- ** types can be conveniently redefined at compile-type. Like this:
- **
- ** cc '-DUINTPTR_TYPE=long long int' ...
- */
- #ifndef UINT32_TYPE
- # ifdef HAVE_UINT32_T
- # define UINT32_TYPE uint32_t
- # else
- # define UINT32_TYPE unsigned int
- # endif
- #endif
- #ifndef UINT16_TYPE
- # ifdef HAVE_UINT16_T
- # define UINT16_TYPE uint16_t
- # else
- # define UINT16_TYPE unsigned short int
- # endif
- #endif
- #ifndef INT16_TYPE
- # ifdef HAVE_INT16_T
- # define INT16_TYPE int16_t
- # else
- # define INT16_TYPE short int
- # endif
- #endif
- #ifndef UINT8_TYPE
- # ifdef HAVE_UINT8_T
- # define UINT8_TYPE uint8_t
- # else
- # define UINT8_TYPE unsigned char
- # endif
- #endif
- #ifndef INT8_TYPE
- # ifdef HAVE_INT8_T
- # define INT8_TYPE int8_t
- # else
- # define INT8_TYPE signed char
- # endif
- #endif
- #ifndef LONGDOUBLE_TYPE
- # define LONGDOUBLE_TYPE long double
- #endif
- typedef sqlite_int64 i64; /* 8-byte signed integer */
- typedef sqlite_uint64 u64; /* 8-byte unsigned integer */
- typedef UINT32_TYPE u32; /* 4-byte unsigned integer */
- typedef UINT16_TYPE u16; /* 2-byte unsigned integer */
- typedef INT16_TYPE i16; /* 2-byte signed integer */
- typedef UINT8_TYPE u8; /* 1-byte unsigned integer */
- typedef INT8_TYPE i8; /* 1-byte signed integer */
- /*
- ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
- ** that can be stored in a u32 without loss of data. The value
- ** is 0x00000000ffffffff. But because of quirks of some compilers, we
- ** have to specify the value in the less intuitive manner shown:
- */
- #define SQLITE_MAX_U32 ((((u64)1)<<32)-1)
- /*
- ** The datatype used to store estimates of the number of rows in a
- ** table or index. This is an unsigned integer type. For 99.9% of
- ** the world, a 32-bit integer is sufficient. But a 64-bit integer
- ** can be used at compile-time if desired.
- */
- #ifdef SQLITE_64BIT_STATS
- typedef u64 tRowcnt; /* 64-bit only if requested at compile-time */
- #else
- typedef u32 tRowcnt; /* 32-bit is the default */
- #endif
- /*
- ** Macros to determine whether the machine is big or little endian,
- ** evaluated at runtime.
- */
- #ifdef SQLITE_AMALGAMATION
- SQLITE_PRIVATE const int sqlite3one = 1;
- #else
- SQLITE_PRIVATE const int sqlite3one;
- #endif
- #if defined(i386) || defined(__i386__) || defined(_M_IX86)\
- || defined(__x86_64) || defined(__x86_64__)
- # define SQLITE_BIGENDIAN 0
- # define SQLITE_LITTLEENDIAN 1
- # define SQLITE_UTF16NATIVE SQLITE_UTF16LE
- #else
- # define SQLITE_BIGENDIAN (*(char *)(&sqlite3one)==0)
- # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
- # define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
- #endif
- /*
- ** Constants for the largest and smallest possible 64-bit signed integers.
- ** These macros are designed to work correctly on both 32-bit and 64-bit
- ** compilers.
- */
- #define LARGEST_INT64 (0xffffffff|(((i64)0x7fffffff)<<32))
- #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
- /*
- ** Round up a number to the next larger multiple of 8. This is used
- ** to force 8-byte alignment on 64-bit architectures.
- */
- #define ROUND8(x) (((x)+7)&~7)
- /*
- ** Round down to the nearest multiple of 8
- */
- #define ROUNDDOWN8(x) ((x)&~7)
- /*
- ** Assert that the pointer X is aligned to an 8-byte boundary. This
- ** macro is used only within assert() to verify that the code gets
- ** all alignment restrictions correct.
- **
- ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
- ** underlying malloc() implemention might return us 4-byte aligned
- ** pointers. In that case, only verify 4-byte alignment.
- */
- #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
- # define EIGHT_BYTE_ALIGNMENT(X) ((((char*)(X) - (char*)0)&3)==0)
- #else
- # define EIGHT_BYTE_ALIGNMENT(X) ((((char*)(X) - (char*)0)&7)==0)
- #endif
- /*
- ** An instance of the following structure is used to store the busy-handler
- ** callback for a given sqlite handle.
- **
- ** The sqlite.busyHandler member of the sqlite struct contains the busy
- ** callback for the database handle. Each pager opened via the sqlite
- ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
- ** callback is currently invoked only from within pager.c.
- */
- typedef struct BusyHandler BusyHandler;
- struct BusyHandler {
- int (*xFunc)(void *,int); /* The busy callback */
- void *pArg; /* First arg to busy callback */
- int nBusy; /* Incremented with each busy call */
- };
- /*
- ** Name of the master database table. The master database table
- ** is a special table that holds the names and attributes of all
- ** user tables and indices.
- */
- #define MASTER_NAME "sqlite_master"
- #define TEMP_MASTER_NAME "sqlite_temp_master"
- /*
- ** The root-page of the master database table.
- */
- #define MASTER_ROOT 1
- /*
- ** The name of the schema table.
- */
- #define SCHEMA_TABLE(x) ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
- /*
- ** A convenience macro that returns the number of elements in
- ** an array.
- */
- #define ArraySize(X) ((int)(sizeof(X)/sizeof(X[0])))
- /*
- ** The following value as a destructor means to use sqlite3DbFree().
- ** The sqlite3DbFree() routine requires two parameters instead of the
- ** one parameter that destructors normally want. So we have to introduce
- ** this magic value that the code knows to handle differently. Any
- ** pointer will work here as long as it is distinct from SQLITE_STATIC
- ** and SQLITE_TRANSIENT.
- */
- #define SQLITE_DYNAMIC ((sqlite3_destructor_type)sqlite3MallocSize)
- /*
- ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
- ** not support Writable Static Data (WSD) such as global and static variables.
- ** All variables must either be on the stack or dynamically allocated from
- ** the heap. When WSD is unsupported, the variable declarations scattered
- ** throughout the SQLite code must become constants instead. The SQLITE_WSD
- ** macro is used for this purpose. And instead of referencing the variable
- ** directly, we use its constant as a key to lookup the run-time allocated
- ** buffer that holds real variable. The constant is also the initializer
- ** for the run-time allocated buffer.
- **
- ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
- ** macros become no-ops and have zero performance impact.
- */
- #ifdef SQLITE_OMIT_WSD
- #define SQLITE_WSD const
- #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
- #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
- SQLITE_API int sqlite3_wsd_init(int N, int J);
- SQLITE_API void *sqlite3_wsd_find(void *K, int L);
- #else
- #define SQLITE_WSD
- #define GLOBAL(t,v) v
- #define sqlite3GlobalConfig sqlite3Config
- #endif
- /*
- ** The following macros are used to suppress compiler warnings and to
- ** make it clear to human readers when a function parameter is deliberately
- ** left unused within the body of a function. This usually happens when
- ** a function is called via a function pointer. For example the
- ** implementation of an SQL aggregate step callback may not use the
- ** parameter indicating the number of arguments passed to the aggregate,
- ** if it knows that this is enforced elsewhere.
- **
- ** When a function parameter is not used at all within the body of a function,
- ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
- ** However, these macros may also be used to suppress warnings related to
- ** parameters that may or may not be used depending on compilation options.
- ** For example those parameters only used in assert() statements. In these
- ** cases the parameters are named as per the usual conventions.
- */
- #define UNUSED_PARAMETER(x) (void)(x)
- #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
- /*
- ** Forward references to structures
- */
- typedef struct AggInfo AggInfo;
- typedef struct AuthContext AuthContext;
- typedef struct AutoincInfo AutoincInfo;
- typedef struct Bitvec Bitvec;
- typedef struct CollSeq CollSeq;
- typedef struct Column Column;
- typedef struct Db Db;
- typedef struct Schema Schema;
- typedef struct Expr Expr;
- typedef struct ExprList ExprList;
- typedef struct ExprSpan ExprSpan;
- typedef struct FKey FKey;
- typedef struct FuncDestructor FuncDestructor;
- typedef struct FuncDef FuncDef;
- typedef struct FuncDefHash FuncDefHash;
- typedef struct IdList IdList;
- typedef struct Index Index;
- typedef struct IndexSample IndexSample;
- typedef struct KeyClass KeyClass;
- typedef struct KeyInfo KeyInfo;
- typedef struct Lookaside Lookaside;
- typedef struct LookasideSlot LookasideSlot;
- typedef struct Module Module;
- typedef struct NameContext NameContext;
- typedef struct Parse Parse;
- typedef struct RowSet RowSet;
- typedef struct Savepoint Savepoint;
- typedef struct Select Select;
- typedef struct SrcList SrcList;
- typedef struct StrAccum StrAccum;
- typedef struct Table Table;
- typedef struct TableLock TableLock;
- typedef struct Token Token;
- typedef struct Trigger Trigger;
- typedef struct TriggerPrg TriggerPrg;
- typedef struct TriggerStep TriggerStep;
- typedef struct UnpackedRecord UnpackedRecord;
- typedef struct VTable VTable;
- typedef struct VtabCtx VtabCtx;
- typedef struct Walker Walker;
- typedef struct WherePlan WherePlan;
- typedef struct WhereInfo WhereInfo;
- typedef struct WhereLevel WhereLevel;
- /*
- ** Defer sourcing vdbe.h and btree.h until after the "u8" and
- ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
- ** pointer types (i.e. FuncDef) defined above.
- */
- /************** Include btree.h in the middle of sqliteInt.h *****************/
- /************** Begin file btree.h *******************************************/
- /*
- ** 2001 September 15
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- ** This header file defines the interface that the sqlite B-Tree file
- ** subsystem. See comments in the source code for a detailed description
- ** of what each interface routine does.
- */
- #ifndef _BTREE_H_
- #define _BTREE_H_
- /* TODO: This definition is just included so other modules compile. It
- ** needs to be revisited.
- */
- #define SQLITE_N_BTREE_META 10
- /*
- ** If defined as non-zero, auto-vacuum is enabled by default. Otherwise
- ** it must be turned on for each database using "PRAGMA auto_vacuum = 1".
- */
- #ifndef SQLITE_DEFAULT_AUTOVACUUM
- #define SQLITE_DEFAULT_AUTOVACUUM 0
- #endif
- #define BTREE_AUTOVACUUM_NONE 0 /* Do not do auto-vacuum */
- #define BTREE_AUTOVACUUM_FULL 1 /* Do full auto-vacuum */
- #define BTREE_AUTOVACUUM_INCR 2 /* Incremental vacuum */
- /*
- ** Forward declarations of structure
- */
- typedef struct Btree Btree;
- typedef struct BtCursor BtCursor;
- typedef struct BtShared BtShared;
- SQLITE_PRIVATE int sqlite3BtreeOpen(
- sqlite3_vfs *pVfs, /* VFS to use with this b-tree */
- const char *zFilename, /* Name of database file to open */
- sqlite3 *db, /* Associated database connection */
- Btree **ppBtree, /* Return open Btree* here */
- int flags, /* Flags */
- int vfsFlags /* Flags passed through to VFS open */
- );
- /* The flags parameter to sqlite3BtreeOpen can be the bitwise or of the
- ** following values.
- **
- ** NOTE: These values must match the corresponding PAGER_ values in
- ** pager.h.
- */
- #define BTREE_OMIT_JOURNAL 1 /* Do not create or use a rollback journal */
- #define BTREE_MEMORY 2 /* This is an in-memory DB */
- #define BTREE_SINGLE 4 /* The file contains at most 1 b-tree */
- #define BTREE_UNORDERED 8 /* Use of a hash implementation is OK */
- SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
- SQLITE_PRIVATE int sqlite3BtreeSetSafetyLevel(Btree*,int,int,int);
- SQLITE_PRIVATE int sqlite3BtreeSyncDisabled(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int nPagesize, int nReserve, int eFix);
- SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeMaxPageCount(Btree*,int);
- SQLITE_PRIVATE u32 sqlite3BtreeLastPage(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeSecureDelete(Btree*,int);
- SQLITE_PRIVATE int sqlite3BtreeGetReserve(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *, int);
- SQLITE_PRIVATE int sqlite3BtreeGetAutoVacuum(Btree *);
- SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree*,int);
- SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree*, const char *zMaster);
- SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree*, int);
- SQLITE_PRIVATE int sqlite3BtreeCommit(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeRollback(Btree*,int);
- SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree*,int);
- SQLITE_PRIVATE int sqlite3BtreeCreateTable(Btree*, int*, int flags);
- SQLITE_PRIVATE int sqlite3BtreeIsInTrans(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeIsInReadTrans(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeIsInBackup(Btree*);
- SQLITE_PRIVATE void *sqlite3BtreeSchema(Btree *, int, void(*)(void *));
- SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *pBtree);
- SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *pBtree, int iTab, u8 isWriteLock);
- SQLITE_PRIVATE int sqlite3BtreeSavepoint(Btree *, int, int);
- SQLITE_PRIVATE const char *sqlite3BtreeGetFilename(Btree *);
- SQLITE_PRIVATE const char *sqlite3BtreeGetJournalname(Btree *);
- SQLITE_PRIVATE int sqlite3BtreeCopyFile(Btree *, Btree *);
- SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *);
- /* The flags parameter to sqlite3BtreeCreateTable can be the bitwise OR
- ** of the flags shown below.
- **
- ** Every SQLite table must have either BTREE_INTKEY or BTREE_BLOBKEY set.
- ** With BTREE_INTKEY, the table key is a 64-bit integer and arbitrary data
- ** is stored in the leaves. (BTREE_INTKEY is used for SQL tables.) With
- ** BTREE_BLOBKEY, the key is an arbitrary BLOB and no content is stored
- ** anywhere - the key is the content. (BTREE_BLOBKEY is used for SQL
- ** indices.)
- */
- #define BTREE_INTKEY 1 /* Table has only 64-bit signed integer keys */
- #define BTREE_BLOBKEY 2 /* Table has keys only - no data */
- SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree*, int, int*);
- SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree*, int, int*);
- SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree*, int);
- SQLITE_PRIVATE void sqlite3BtreeGetMeta(Btree *pBtree, int idx, u32 *pValue);
- SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
- /*
- ** The second parameter to sqlite3BtreeGetMeta or sqlite3BtreeUpdateMeta
- ** should be one of the following values. The integer values are assigned
- ** to constants so that the offset of the corresponding field in an
- ** SQLite database header may be found using the following formula:
- **
- ** offset = 36 + (idx * 4)
- **
- ** For example, the free-page-count field is located at byte offset 36 of
- ** the database file header. The incr-vacuum-flag field is located at
- ** byte offset 64 (== 36+4*7).
- */
- #define BTREE_FREE_PAGE_COUNT 0
- #define BTREE_SCHEMA_VERSION 1
- #define BTREE_FILE_FORMAT 2
- #define BTREE_DEFAULT_CACHE_SIZE 3
- #define BTREE_LARGEST_ROOT_PAGE 4
- #define BTREE_TEXT_ENCODING 5
- #define BTREE_USER_VERSION 6
- #define BTREE_INCR_VACUUM 7
- SQLITE_PRIVATE int sqlite3BtreeCursor(
- Btree*, /* BTree containing table to open */
- int iTable, /* Index of root page */
- int wrFlag, /* 1 for writing. 0 for read-only */
- struct KeyInfo*, /* First argument to compare function */
- BtCursor *pCursor /* Space to write cursor structure */
- );
- SQLITE_PRIVATE int sqlite3BtreeCursorSize(void);
- SQLITE_PRIVATE void sqlite3BtreeCursorZero(BtCursor*);
- SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor*);
- SQLITE_PRIVATE int sqlite3BtreeMovetoUnpacked(
- BtCursor*,
- UnpackedRecord *pUnKey,
- i64 intKey,
- int bias,
- int *pRes
- );
- SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor*, int*);
- SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor*);
- SQLITE_PRIVATE int sqlite3BtreeInsert(BtCursor*, const void *pKey, i64 nKey,
- const void *pData, int nData,
- int nZero, int bias, int seekResult);
- SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor*, int *pRes);
- SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor*, int *pRes);
- SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor*, int *pRes);
- SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor*);
- SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor*, int *pRes);
- SQLITE_PRIVATE int sqlite3BtreeKeySize(BtCursor*, i64 *pSize);
- SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*);
- SQLITE_PRIVATE const void *sqlite3BtreeKeyFetch(BtCursor*, int *pAmt);
- SQLITE_PRIVATE const void *sqlite3BtreeDataFetch(BtCursor*, int *pAmt);
- SQLITE_PRIVATE int sqlite3BtreeDataSize(BtCursor*, u32 *pSize);
- SQLITE_PRIVATE int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);
- SQLITE_PRIVATE void sqlite3BtreeSetCachedRowid(BtCursor*, sqlite3_int64);
- SQLITE_PRIVATE sqlite3_int64 sqlite3BtreeGetCachedRowid(BtCursor*);
- SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
- SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);
- SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
- SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *);
- SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *);
- SQLITE_PRIVATE int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
- #ifndef NDEBUG
- SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor*);
- #endif
- #ifndef SQLITE_OMIT_BTREECOUNT
- SQLITE_PRIVATE int sqlite3BtreeCount(BtCursor *, i64 *);
- #endif
- #ifdef SQLITE_TEST
- SQLITE_PRIVATE int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
- SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
- #endif
- #ifndef SQLITE_OMIT_WAL
- SQLITE_PRIVATE int sqlite3BtreeCheckpoint(Btree*, int, int *, int *);
- #endif
- /*
- ** If we are not using shared cache, then there is no need to
- ** use mutexes to access the BtShared structures. So make the
- ** Enter and Leave procedures no-ops.
- */
- #ifndef SQLITE_OMIT_SHARED_CACHE
- SQLITE_PRIVATE void sqlite3BtreeEnter(Btree*);
- SQLITE_PRIVATE void sqlite3BtreeEnterAll(sqlite3*);
- #else
- # define sqlite3BtreeEnter(X)
- # define sqlite3BtreeEnterAll(X)
- #endif
- #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE
- SQLITE_PRIVATE int sqlite3BtreeSharable(Btree*);
- SQLITE_PRIVATE void sqlite3BtreeLeave(Btree*);
- SQLITE_PRIVATE void sqlite3BtreeEnterCursor(BtCursor*);
- SQLITE_PRIVATE void sqlite3BtreeLeaveCursor(BtCursor*);
- SQLITE_PRIVATE void sqlite3BtreeLeaveAll(sqlite3*);
- #ifndef NDEBUG
- /* These routines are used inside assert() statements only. */
- SQLITE_PRIVATE int sqlite3BtreeHoldsMutex(Btree*);
- SQLITE_PRIVATE int sqlite3BtreeHoldsAllMutexes(sqlite3*);
- SQLITE_PRIVATE int sqlite3SchemaMutexHeld(sqlite3*,int,Schema*);
- #endif
- #else
- # define sqlite3BtreeSharable(X) 0
- # define sqlite3BtreeLeave(X)
- # define sqlite3BtreeEnterCursor(X)
- # define sqlite3BtreeLeaveCursor(X)
- # define sqlite3BtreeLeaveAll(X)
- # define sqlite3BtreeHoldsMutex(X) 1
- # define sqlite3BtreeHoldsAllMutexes(X) 1
- # define sqlite3SchemaMutexHeld(X,Y,Z) 1
- #endif
- #endif /* _BTREE_H_ */
- /************** End of btree.h ***********************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /************** Include vdbe.h in the middle of sqliteInt.h ******************/
- /************** Begin file vdbe.h ********************************************/
- /*
- ** 2001 September 15
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- ** Header file for the Virtual DataBase Engine (VDBE)
- **
- ** This header defines the interface to the virtual database engine
- ** or VDBE. The VDBE implements an abstract machine that runs a
- ** simple program to access and modify the underlying database.
- */
- #ifndef _SQLITE_VDBE_H_
- #define _SQLITE_VDBE_H_
- /* #include <stdio.h> */
- /*
- ** A single VDBE is an opaque structure named "Vdbe". Only routines
- ** in the source file sqliteVdbe.c are allowed to see the insides
- ** of this structure.
- */
- typedef struct Vdbe Vdbe;
- /*
- ** The names of the following types declared in vdbeInt.h are required
- ** for the VdbeOp definition.
- */
- typedef struct VdbeFunc VdbeFunc;
- typedef struct Mem Mem;
- typedef struct SubProgram SubProgram;
- /*
- ** A single instruction of the virtual machine has an opcode
- ** and as many as three operands. The instruction is recorded
- ** as an instance of the following structure:
- */
- struct VdbeOp {
- u8 opcode; /* What operation to perform */
- signed char p4type; /* One of the P4_xxx constants for p4 */
- u8 opflags; /* Mask of the OPFLG_* flags in opcodes.h */
- u8 p5; /* Fifth parameter is an unsigned character */
- int p1; /* First operand */
- int p2; /* Second parameter (often the jump destination) */
- int p3; /* The third parameter */
- union { /* fourth parameter */
- int i; /* Integer value if p4type==P4_INT32 */
- void *p; /* Generic pointer */
- char *z; /* Pointer to data for string (char array) types */
- i64 *pI64; /* Used when p4type is P4_INT64 */
- double *pReal; /* Used when p4type is P4_REAL */
- FuncDef *pFunc; /* Used when p4type is P4_FUNCDEF */
- VdbeFunc *pVdbeFunc; /* Used when p4type is P4_VDBEFUNC */
- CollSeq *pColl; /* Used when p4type is P4_COLLSEQ */
- Mem *pMem; /* Used when p4type is P4_MEM */
- VTable *pVtab; /* Used when p4type is P4_VTAB */
- KeyInfo *pKeyInfo; /* Used when p4type is P4_KEYINFO */
- int *ai; /* Used when p4type is P4_INTARRAY */
- SubProgram *pProgram; /* Used when p4type is P4_SUBPROGRAM */
- int (*xAdvance)(BtCursor *, int *);
- } p4;
- #ifdef SQLITE_DEBUG
- char *zComment; /* Comment to improve readability */
- #endif
- #ifdef VDBE_PROFILE
- int cnt; /* Number of times this instruction was executed */
- u64 cycles; /* Total time spent executing this instruction */
- #endif
- };
- typedef struct VdbeOp VdbeOp;
- /*
- ** A sub-routine used to implement a trigger program.
- */
- struct SubProgram {
- VdbeOp *aOp; /* Array of opcodes for sub-program */
- int nOp; /* Elements in aOp[] */
- int nMem; /* Number of memory cells required */
- int nCsr; /* Number of cursors required */
- int nOnce; /* Number of OP_Once instructions */
- void *token; /* id that may be used to recursive triggers */
- SubProgram *pNext; /* Next sub-program already visited */
- };
- /*
- ** A smaller version of VdbeOp used for the VdbeAddOpList() function because
- ** it takes up less space.
- */
- struct VdbeOpList {
- u8 opcode; /* What operation to perform */
- signed char p1; /* First operand */
- signed char p2; /* Second parameter (often the jump destination) */
- signed char p3; /* Third parameter */
- };
- typedef struct VdbeOpList VdbeOpList;
- /*
- ** Allowed values of VdbeOp.p4type
- */
- #define P4_NOTUSED 0 /* The P4 parameter is not used */
- #define P4_DYNAMIC (-1) /* Pointer to a string obtained from sqliteMalloc() */
- #define P4_STATIC (-2) /* Pointer to a static string */
- #define P4_COLLSEQ (-4) /* P4 is a pointer to a CollSeq structure */
- #define P4_FUNCDEF (-5) /* P4 is a pointer to a FuncDef structure */
- #define P4_KEYINFO (-6) /* P4 is a pointer to a KeyInfo structure */
- #define P4_VDBEFUNC (-7) /* P4 is a pointer to a VdbeFunc structure */
- #define P4_MEM (-8) /* P4 is a pointer to a Mem* structure */
- #define P4_TRANSIENT 0 /* P4 is a pointer to a transient string */
- #define P4_VTAB (-10) /* P4 is a pointer to an sqlite3_vtab structure */
- #define P4_MPRINTF (-11) /* P4 is a string obtained from sqlite3_mprintf() */
- #define P4_REAL (-12) /* P4 is a 64-bit floating point value */
- #define P4_INT64 (-13) /* P4 is a 64-bit signed integer */
- #define P4_INT32 (-14) /* P4 is a 32-bit signed integer */
- #define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
- #define P4_SUBPROGRAM (-18) /* P4 is a pointer to a SubProgram structure */
- #define P4_ADVANCE (-19) /* P4 is a pointer to BtreeNext() or BtreePrev() */
- /* When adding a P4 argument using P4_KEYINFO, a copy of the KeyInfo structure
- ** is made. That copy is freed when the Vdbe is finalized. But if the
- ** argument is P4_KEYINFO_HANDOFF, the passed in pointer is used. It still
- ** gets freed when the Vdbe is finalized so it still should be obtained
- ** from a single sqliteMalloc(). But no copy is made and the calling
- ** function should *not* try to free the KeyInfo.
- */
- #define P4_KEYINFO_HANDOFF (-16)
- #define P4_KEYINFO_STATIC (-17)
- /*
- ** The Vdbe.aColName array contains 5n Mem structures, where n is the
- ** number of columns of data returned by the statement.
- */
- #define COLNAME_NAME 0
- #define COLNAME_DECLTYPE 1
- #define COLNAME_DATABASE 2
- #define COLNAME_TABLE 3
- #define COLNAME_COLUMN 4
- #ifdef SQLITE_ENABLE_COLUMN_METADATA
- # define COLNAME_N 5 /* Number of COLNAME_xxx symbols */
- #else
- # ifdef SQLITE_OMIT_DECLTYPE
- # define COLNAME_N 1 /* Store only the name */
- # else
- # define COLNAME_N 2 /* Store the name and decltype */
- # endif
- #endif
- /*
- ** The following macro converts a relative address in the p2 field
- ** of a VdbeOp structure into a negative number so that
- ** sqlite3VdbeAddOpList() knows that the address is relative. Calling
- ** the macro again restores the address.
- */
- #define ADDR(X) (-1-(X))
- /*
- ** The makefile scans the vdbe.c source file and creates the "opcodes.h"
- ** header file that defines a number for each opcode used by the VDBE.
- */
- /************** Include opcodes.h in the middle of vdbe.h ********************/
- /************** Begin file opcodes.h *****************************************/
- /* Automatically generated. Do not edit */
- /* See the mkopcodeh.awk script for details */
- #define OP_Goto 1
- #define OP_Gosub 2
- #define OP_Return 3
- #define OP_Yield 4
- #define OP_HaltIfNull 5
- #define OP_Halt 6
- #define OP_Integer 7
- #define OP_Int64 8
- #define OP_Real 130 /* same as TK_FLOAT */
- #define OP_String8 94 /* same as TK_STRING */
- #define OP_String 9
- #define OP_Null 10
- #define OP_Blob 11
- #define OP_Variable 12
- #define OP_Move 13
- #define OP_Copy 14
- #define OP_SCopy 15
- #define OP_ResultRow 16
- #define OP_Concat 91 /* same as TK_CONCAT */
- #define OP_Add 86 /* same as TK_PLUS */
- #define OP_Subtract 87 /* same as TK_MINUS */
- #define OP_Multiply 88 /* same as TK_STAR */
- #define OP_Divide 89 /* same as TK_SLASH */
- #define OP_Remainder 90 /* same as TK_REM */
- #define OP_CollSeq 17
- #define OP_Function 18
- #define OP_BitAnd 82 /* same as TK_BITAND */
- #define OP_BitOr 83 /* same as TK_BITOR */
- #define OP_ShiftLeft 84 /* same as TK_LSHIFT */
- #define OP_ShiftRight 85 /* same as TK_RSHIFT */
- #define OP_AddImm 20
- #define OP_MustBeInt 21
- #define OP_RealAffinity 22
- #define OP_ToText 141 /* same as TK_TO_TEXT */
- #define OP_ToBlob 142 /* same as TK_TO_BLOB */
- #define OP_ToNumeric 143 /* same as TK_TO_NUMERIC*/
- #define OP_ToInt 144 /* same as TK_TO_INT */
- #define OP_ToReal 145 /* same as TK_TO_REAL */
- #define OP_Eq 76 /* same as TK_EQ */
- #define OP_Ne 75 /* same as TK_NE */
- #define OP_Lt 79 /* same as TK_LT */
- #define OP_Le 78 /* same as TK_LE */
- #define OP_Gt 77 /* same as TK_GT */
- #define OP_Ge 80 /* same as TK_GE */
- #define OP_Permutation 23
- #define OP_Compare 24
- #define OP_Jump 25
- #define OP_And 69 /* same as TK_AND */
- #define OP_Or 68 /* same as TK_OR */
- #define OP_Not 19 /* same as TK_NOT */
- #define OP_BitNot 93 /* same as TK_BITNOT */
- #define OP_Once 26
- #define OP_If 27
- #define OP_IfNot 28
- #define OP_IsNull 73 /* same as TK_ISNULL */
- #define OP_NotNull 74 /* same as TK_NOTNULL */
- #define OP_Column 29
- #define OP_Affinity 30
- #define OP_MakeRecord 31
- #define OP_Count 32
- #define OP_Savepoint 33
- #define OP_AutoCommit 34
- #define OP_Transaction 35
- #define OP_ReadCookie 36
- #define OP_SetCookie 37
- #define OP_VerifyCookie 38
- #define OP_OpenRead 39
- #define OP_OpenWrite 40
- #define OP_OpenAutoindex 41
- #define OP_OpenEphemeral 42
- #define OP_SorterOpen 43
- #define OP_OpenPseudo 44
- #define OP_Close 45
- #define OP_SeekLt 46
- #define OP_SeekLe 47
- #define OP_SeekGe 48
- #define OP_SeekGt 49
- #define OP_Seek 50
- #define OP_NotFound 51
- #define OP_Found 52
- #define OP_IsUnique 53
- #define OP_NotExists 54
- #define OP_Sequence 55
- #define OP_NewRowid 56
- #define OP_Insert 57
- #define OP_InsertInt 58
- #define OP_Delete 59
- #define OP_ResetCount 60
- #define OP_SorterCompare 61
- #define OP_SorterData 62
- #define OP_RowKey 63
- #define OP_RowData 64
- #define OP_Rowid 65
- #define OP_NullRow 66
- #define OP_Last 67
- #define OP_SorterSort 70
- #define OP_Sort 71
- #define OP_Rewind 72
- #define OP_SorterNext 81
- #define OP_Prev 92
- #define OP_Next 95
- #define OP_SorterInsert 96
- #define OP_IdxInsert 97
- #define OP_IdxDelete 98
- #define OP_IdxRowid 99
- #define OP_IdxLT 100
- #define OP_IdxGE 101
- #define OP_Destroy 102
- #define OP_Clear 103
- #define OP_CreateIndex 104
- #define OP_CreateTable 105
- #define OP_ParseSchema 106
- #define OP_LoadAnalysis 107
- #define OP_DropTable 108
- #define OP_DropIndex 109
- #define OP_DropTrigger 110
- #define OP_IntegrityCk 111
- #define OP_RowSetAdd 112
- #define OP_RowSetRead 113
- #define OP_RowSetTest 114
- #define OP_Program 115
- #define OP_Param 116
- #define OP_FkCounter 117
- #define OP_FkIfZero 118
- #define OP_MemMax 119
- #define OP_IfPos 120
- #define OP_IfNeg 121
- #define OP_IfZero 122
- #define OP_AggStep 123
- #define OP_AggFinal 124
- #define OP_Checkpoint 125
- #define OP_JournalMode 126
- #define OP_Vacuum 127
- #define OP_IncrVacuum 128
- #define OP_Expire 129
- #define OP_TableLock 131
- #define OP_VBegin 132
- #define OP_VCreate 133
- #define OP_VDestroy 134
- #define OP_VOpen 135
- #define OP_VFilter 136
- #define OP_VColumn 137
- #define OP_VNext 138
- #define OP_VRename 139
- #define OP_VUpdate 140
- #define OP_Pagecount 146
- #define OP_MaxPgcnt 147
- #define OP_Trace 148
- #define OP_Noop 149
- #define OP_Explain 150
- /* Properties such as "out2" or "jump" that are specified in
- ** comments following the "case" for each opcode in the vdbe.c
- ** are encoded into bitvectors as follows:
- */
- #define OPFLG_JUMP 0x0001 /* jump: P2 holds jmp target */
- #define OPFLG_OUT2_PRERELEASE 0x0002 /* out2-prerelease: */
- #define OPFLG_IN1 0x0004 /* in1: P1 is an input */
- #define OPFLG_IN2 0x0008 /* in2: P2 is an input */
- #define OPFLG_IN3 0x0010 /* in3: P3 is an input */
- #define OPFLG_OUT2 0x0020 /* out2: P2 is an output */
- #define OPFLG_OUT3 0x0040 /* out3: P3 is an output */
- #define OPFLG_INITIALIZER {\
- /* 0 */ 0x00, 0x01, 0x01, 0x04, 0x04, 0x10, 0x00, 0x02,\
- /* 8 */ 0x02, 0x02, 0x02, 0x02, 0x02, 0x00, 0x24, 0x24,\
- /* 16 */ 0x00, 0x00, 0x00, 0x24, 0x04, 0x05, 0x04, 0x00,\
- /* 24 */ 0x00, 0x01, 0x01, 0x05, 0x05, 0x00, 0x00, 0x00,\
- /* 32 */ 0x02, 0x00, 0x00, 0x00, 0x02, 0x10, 0x00, 0x00,\
- /* 40 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x11, 0x11,\
- /* 48 */ 0x11, 0x11, 0x08, 0x11, 0x11, 0x11, 0x11, 0x02,\
- /* 56 */ 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
- /* 64 */ 0x00, 0x02, 0x00, 0x01, 0x4c, 0x4c, 0x01, 0x01,\
- /* 72 */ 0x01, 0x05, 0x05, 0x15, 0x15, 0x15, 0x15, 0x15,\
- /* 80 */ 0x15, 0x01, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c,\
- /* 88 */ 0x4c, 0x4c, 0x4c, 0x4c, 0x01, 0x24, 0x02, 0x01,\
- /* 96 */ 0x08, 0x08, 0x00, 0x02, 0x01, 0x01, 0x02, 0x00,\
- /* 104 */ 0x02, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
- /* 112 */ 0x0c, 0x45, 0x15, 0x01, 0x02, 0x00, 0x01, 0x08,\
- /* 120 */ 0x05, 0x05, 0x05, 0x00, 0x00, 0x00, 0x02, 0x00,\
- /* 128 */ 0x01, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,\
- /* 136 */ 0x01, 0x00, 0x01, 0x00, 0x00, 0x04, 0x04, 0x04,\
- /* 144 */ 0x04, 0x04, 0x02, 0x02, 0x00, 0x00, 0x00,}
- /************** End of opcodes.h *********************************************/
- /************** Continuing where we left off in vdbe.h ***********************/
- /*
- ** Prototypes for the VDBE interface. See comments on the implementation
- ** for a description of what each of these routines does.
- */
- SQLITE_PRIVATE Vdbe *sqlite3VdbeCreate(sqlite3*);
- SQLITE_PRIVATE int sqlite3VdbeAddOp0(Vdbe*,int);
- SQLITE_PRIVATE int sqlite3VdbeAddOp1(Vdbe*,int,int);
- SQLITE_PRIVATE int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
- SQLITE_PRIVATE int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
- SQLITE_PRIVATE int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
- SQLITE_PRIVATE int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
- SQLITE_PRIVATE int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp);
- SQLITE_PRIVATE void sqlite3VdbeAddParseSchemaOp(Vdbe*,int,char*);
- SQLITE_PRIVATE void sqlite3VdbeChangeP1(Vdbe*, u32 addr, int P1);
- SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe*, u32 addr, int P2);
- SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe*, u32 addr, int P3);
- SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe*, u8 P5);
- SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe*, int addr);
- SQLITE_PRIVATE void sqlite3VdbeChangeToNoop(Vdbe*, int addr);
- SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
- SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe*, int);
- SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
- SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
- SQLITE_PRIVATE void sqlite3VdbeRunOnlyOnce(Vdbe*);
- SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
- SQLITE_PRIVATE void sqlite3VdbeDeleteObject(sqlite3*,Vdbe*);
- SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,Parse*);
- SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
- SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);
- SQLITE_PRIVATE int sqlite3VdbeCurrentAddr(Vdbe*);
- #ifdef SQLITE_DEBUG
- SQLITE_PRIVATE int sqlite3VdbeAssertMayAbort(Vdbe *, int);
- SQLITE_PRIVATE void sqlite3VdbeTrace(Vdbe*,FILE*);
- #endif
- SQLITE_PRIVATE void sqlite3VdbeResetStepResult(Vdbe*);
- SQLITE_PRIVATE void sqlite3VdbeRewind(Vdbe*);
- SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe*);
- SQLITE_PRIVATE void sqlite3VdbeSetNumCols(Vdbe*,int);
- SQLITE_PRIVATE int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*));
- SQLITE_PRIVATE void sqlite3VdbeCountChanges(Vdbe*);
- SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe*);
- SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
- SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
- SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
- SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetValue(Vdbe*, int, u8);
- SQLITE_PRIVATE void sqlite3VdbeSetVarmask(Vdbe*, int);
- #ifndef SQLITE_OMIT_TRACE
- SQLITE_PRIVATE char *sqlite3VdbeExpandSql(Vdbe*, const char*);
- #endif
- SQLITE_PRIVATE void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
- SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
- SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo *, char *, int, char **);
- #ifndef SQLITE_OMIT_TRIGGER
- SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
- #endif
- #ifndef NDEBUG
- SQLITE_PRIVATE void sqlite3VdbeComment(Vdbe*, const char*, ...);
- # define VdbeComment(X) sqlite3VdbeComment X
- SQLITE_PRIVATE void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
- # define VdbeNoopComment(X) sqlite3VdbeNoopComment X
- #else
- # define VdbeComment(X)
- # define VdbeNoopComment(X)
- #endif
- #endif
- /************** End of vdbe.h ************************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /************** Include pager.h in the middle of sqliteInt.h *****************/
- /************** Begin file pager.h *******************************************/
- /*
- ** 2001 September 15
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- ** This header file defines the interface that the sqlite page cache
- ** subsystem. The page cache subsystem reads and writes a file a page
- ** at a time and provides a journal for rollback.
- */
- #ifndef _PAGER_H_
- #define _PAGER_H_
- /*
- ** Default maximum size for persistent journal files. A negative
- ** value means no limit. This value may be overridden using the
- ** sqlite3PagerJournalSizeLimit() API. See also "PRAGMA journal_size_limit".
- */
- #ifndef SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT
- #define SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT -1
- #endif
- /*
- ** The type used to represent a page number. The first page in a file
- ** is called page 1. 0 is used to represent "not a page".
- */
- typedef u32 Pgno;
- /*
- ** Each open file is managed by a separate instance of the "Pager" structure.
- */
- typedef struct Pager Pager;
- /*
- ** Handle type for pages.
- */
- typedef struct PgHdr DbPage;
- /*
- ** Page number PAGER_MJ_PGNO is never used in an SQLite database (it is
- ** reserved for working around a windows/posix incompatibility). It is
- ** used in the journal to signify that the remainder of the journal file
- ** is devoted to storing a master journal name - there are no more pages to
- ** roll back. See comments for function writeMasterJournal() in pager.c
- ** for details.
- */
- #define PAGER_MJ_PGNO(x) ((Pgno)((PENDING_BYTE/((x)->pageSize))+1))
- /*
- ** Allowed values for the flags parameter to sqlite3PagerOpen().
- **
- ** NOTE: These values must match the corresponding BTREE_ values in btree.h.
- */
- #define PAGER_OMIT_JOURNAL 0x0001 /* Do not use a rollback journal */
- #define PAGER_MEMORY 0x0002 /* In-memory database */
- /*
- ** Valid values for the second argument to sqlite3PagerLockingMode().
- */
- #define PAGER_LOCKINGMODE_QUERY -1
- #define PAGER_LOCKINGMODE_NORMAL 0
- #define PAGER_LOCKINGMODE_EXCLUSIVE 1
- /*
- ** Numeric constants that encode the journalmode.
- */
- #define PAGER_JOURNALMODE_QUERY (-1) /* Query the value of journalmode */
- #define PAGER_JOURNALMODE_DELETE 0 /* Commit by deleting journal file */
- #define PAGER_JOURNALMODE_PERSIST 1 /* Commit by zeroing journal header */
- #define PAGER_JOURNALMODE_OFF 2 /* Journal omitted. */
- #define PAGER_JOURNALMODE_TRUNCATE 3 /* Commit by truncating journal */
- #define PAGER_JOURNALMODE_MEMORY 4 /* In-memory journal file */
- #define PAGER_JOURNALMODE_WAL 5 /* Use write-ahead logging */
- /*
- ** The remainder of this file contains the declarations of the functions
- ** that make up the Pager sub-system API. See source code comments for
- ** a detailed description of each routine.
- */
- /* Open and close a Pager connection. */
- SQLITE_PRIVATE int sqlite3PagerOpen(
- sqlite3_vfs*,
- Pager **ppPager,
- const char*,
- int,
- int,
- int,
- void(*)(DbPage*)
- );
- SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager);
- SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager*, int, unsigned char*);
- /* Functions used to configure a Pager object. */
- SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, int(*)(void *), void *);
- SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u32*, int);
- SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
- SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
- SQLITE_PRIVATE void sqlite3PagerShrink(Pager*);
- SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager*,int,int,int);
- SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *, int);
- SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *, int);
- SQLITE_PRIVATE int sqlite3PagerGetJournalMode(Pager*);
- SQLITE_PRIVATE int sqlite3PagerOkToChangeJournalMode(Pager*);
- SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *, i64);
- SQLITE_PRIVATE sqlite3_backup **sqlite3PagerBackupPtr(Pager*);
- /* Functions used to obtain and release page references. */
- SQLITE_PRIVATE int sqlite3PagerAcquire(Pager *pPager, Pgno pgno, DbPage **ppPage, int clrFlag);
- #define sqlite3PagerGet(A,B,C) sqlite3PagerAcquire(A,B,C,0)
- SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno);
- SQLITE_PRIVATE void sqlite3PagerRef(DbPage*);
- SQLITE_PRIVATE void sqlite3PagerUnref(DbPage*);
- /* Operations on page references. */
- SQLITE_PRIVATE int sqlite3PagerWrite(DbPage*);
- SQLITE_PRIVATE void sqlite3PagerDontWrite(DbPage*);
- SQLITE_PRIVATE int sqlite3PagerMovepage(Pager*,DbPage*,Pgno,int);
- SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage*);
- SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *);
- SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *);
- /* Functions used to manage pager transactions and savepoints. */
- SQLITE_PRIVATE void sqlite3PagerPagecount(Pager*, int*);
- SQLITE_PRIVATE int sqlite3PagerBegin(Pager*, int exFlag, int);
- SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);
- SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager*);
- SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager);
- SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager*);
- SQLITE_PRIVATE int sqlite3PagerRollback(Pager*);
- SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
- SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
- SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager);
- SQLITE_PRIVATE int sqlite3PagerCheckpoint(Pager *pPager, int, int*, int*);
- SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager);
- SQLITE_PRIVATE int sqlite3PagerWalCallback(Pager *pPager);
- SQLITE_PRIVATE int sqlite3PagerOpenWal(Pager *pPager, int *pisOpen);
- SQLITE_PRIVATE int sqlite3PagerCloseWal(Pager *pPager);
- #ifdef SQLITE_ENABLE_ZIPVFS
- SQLITE_PRIVATE int sqlite3PagerWalFramesize(Pager *pPager);
- #endif
- /* Functions used to query pager state and configuration. */
- SQLITE_PRIVATE u8 sqlite3PagerIsreadonly(Pager*);
- SQLITE_PRIVATE int sqlite3PagerRefcount(Pager*);
- SQLITE_PRIVATE int sqlite3PagerMemUsed(Pager*);
- SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager*);
- SQLITE_PRIVATE const sqlite3_vfs *sqlite3PagerVfs(Pager*);
- SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager*);
- SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager*);
- SQLITE_PRIVATE int sqlite3PagerNosync(Pager*);
- SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager*);
- SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager*);
- SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *, int, int, int *);
- SQLITE_PRIVATE void sqlite3PagerClearCache(Pager *);
- /* Functions used to truncate the database file. */
- SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager*,Pgno);
- #if defined(SQLITE_HAS_CODEC) && !defined(SQLITE_OMIT_WAL)
- SQLITE_PRIVATE void *sqlite3PagerCodec(DbPage *);
- #endif
- /* Functions to support testing and debugging. */
- #if !defined(NDEBUG) || defined(SQLITE_TEST)
- SQLITE_PRIVATE Pgno sqlite3PagerPagenumber(DbPage*);
- SQLITE_PRIVATE int sqlite3PagerIswriteable(DbPage*);
- #endif
- #ifdef SQLITE_TEST
- SQLITE_PRIVATE int *sqlite3PagerStats(Pager*);
- SQLITE_PRIVATE void sqlite3PagerRefdump(Pager*);
- void disable_simulated_io_errors(void);
- void enable_simulated_io_errors(void);
- #else
- # define disable_simulated_io_errors()
- # define enable_simulated_io_errors()
- #endif
- #endif /* _PAGER_H_ */
- /************** End of pager.h ***********************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /************** Include pcache.h in the middle of sqliteInt.h ****************/
- /************** Begin file pcache.h ******************************************/
- /*
- ** 2008 August 05
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- ** This header file defines the interface that the sqlite page cache
- ** subsystem.
- */
- #ifndef _PCACHE_H_
- typedef struct PgHdr PgHdr;
- typedef struct PCache PCache;
- /*
- ** Every page in the cache is controlled by an instance of the following
- ** structure.
- */
- struct PgHdr {
- sqlite3_pcache_page *pPage; /* Pcache object page handle */
- void *pData; /* Page data */
- void *pExtra; /* Extra content */
- PgHdr *pDirty; /* Transient list of dirty pages */
- Pager *pPager; /* The pager this page is part of */
- Pgno pgno; /* Page number for this page */
- #ifdef SQLITE_CHECK_PAGES
- u32 pageHash; /* Hash of page content */
- #endif
- u16 flags; /* PGHDR flags defined below */
- /**********************************************************************
- ** Elements above are public. All that follows is private to pcache.c
- ** and should not be accessed by other modules.
- */
- i16 nRef; /* Number of users of this page */
- PCache *pCache; /* Cache that owns this page */
- PgHdr *pDirtyNext; /* Next element in list of dirty pages */
- PgHdr *pDirtyPrev; /* Previous element in list of dirty pages */
- };
- /* Bit values for PgHdr.flags */
- #define PGHDR_DIRTY 0x002 /* Page has changed */
- #define PGHDR_NEED_SYNC 0x004 /* Fsync the rollback journal before
- ** writing this page to the database */
- #define PGHDR_NEED_READ 0x008 /* Content is unread */
- #define PGHDR_REUSE_UNLIKELY 0x010 /* A hint that reuse is unlikely */
- #define PGHDR_DONT_WRITE 0x020 /* Do not write content to disk */
- /* Initialize and shutdown the page cache subsystem */
- SQLITE_PRIVATE int sqlite3PcacheInitialize(void);
- SQLITE_PRIVATE void sqlite3PcacheShutdown(void);
- /* Page cache buffer management:
- ** These routines implement SQLITE_CONFIG_PAGECACHE.
- */
- SQLITE_PRIVATE void sqlite3PCacheBufferSetup(void *, int sz, int n);
- /* Create a new pager cache.
- ** Under memory stress, invoke xStress to try to make pages clean.
- ** Only clean and unpinned pages can be reclaimed.
- */
- SQLITE_PRIVATE void sqlite3PcacheOpen(
- int szPage, /* Size of every page */
- int szExtra, /* Extra space associated with each page */
- int bPurgeable, /* True if pages are on backing store */
- int (*xStress)(void*, PgHdr*), /* Call to try to make pages clean */
- void *pStress, /* Argument to xStress */
- PCache *pToInit /* Preallocated space for the PCache */
- );
- /* Modify the page-size after the cache has been created. */
- SQLITE_PRIVATE void sqlite3PcacheSetPageSize(PCache *, int);
- /* Return the size in bytes of a PCache object. Used to preallocate
- ** storage space.
- */
- SQLITE_PRIVATE int sqlite3PcacheSize(void);
- /* One release per successful fetch. Page is pinned until released.
- ** Reference counted.
- */
- SQLITE_PRIVATE int sqlite3PcacheFetch(PCache*, Pgno, int createFlag, PgHdr**);
- SQLITE_PRIVATE void sqlite3PcacheRelease(PgHdr*);
- SQLITE_PRIVATE void sqlite3PcacheDrop(PgHdr*); /* Remove page from cache */
- SQLITE_PRIVATE void sqlite3PcacheMakeDirty(PgHdr*); /* Make sure page is marked dirty */
- SQLITE_PRIVATE void sqlite3PcacheMakeClean(PgHdr*); /* Mark a single page as clean */
- SQLITE_PRIVATE void sqlite3PcacheCleanAll(PCache*); /* Mark all dirty list pages as clean */
- /* Change a page number. Used by incr-vacuum. */
- SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr*, Pgno);
- /* Remove all pages with pgno>x. Reset the cache if x==0 */
- SQLITE_PRIVATE void sqlite3PcacheTruncate(PCache*, Pgno x);
- /* Get a list of all dirty pages in the cache, sorted by page number */
- SQLITE_PRIVATE PgHdr *sqlite3PcacheDirtyList(PCache*);
- /* Reset and close the cache object */
- SQLITE_PRIVATE void sqlite3PcacheClose(PCache*);
- /* Clear flags from pages of the page cache */
- SQLITE_PRIVATE void sqlite3PcacheClearSyncFlags(PCache *);
- /* Discard the contents of the cache */
- SQLITE_PRIVATE void sqlite3PcacheClear(PCache*);
- /* Return the total number of outstanding page references */
- SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache*);
- /* Increment the reference count of an existing page */
- SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr*);
- SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr*);
- /* Return the total number of pages stored in the cache */
- SQLITE_PRIVATE int sqlite3PcachePagecount(PCache*);
- #if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
- /* Iterate through all dirty pages currently stored in the cache. This
- ** interface is only available if SQLITE_CHECK_PAGES is defined when the
- ** library is built.
- */
- SQLITE_PRIVATE void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *));
- #endif
- /* Set and get the suggested cache-size for the specified pager-cache.
- **
- ** If no global maximum is configured, then the system attempts to limit
- ** the total number of pages cached by purgeable pager-caches to the sum
- ** of the suggested cache-sizes.
- */
- SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *, int);
- #ifdef SQLITE_TEST
- SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *);
- #endif
- /* Free up as much memory as possible from the page cache */
- SQLITE_PRIVATE void sqlite3PcacheShrink(PCache*);
- #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
- /* Try to return memory used by the pcache module to the main memory heap */
- SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int);
- #endif
- #ifdef SQLITE_TEST
- SQLITE_PRIVATE void sqlite3PcacheStats(int*,int*,int*,int*);
- #endif
- SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
- #endif /* _PCACHE_H_ */
- /************** End of pcache.h **********************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /************** Include os.h in the middle of sqliteInt.h ********************/
- /************** Begin file os.h **********************************************/
- /*
- ** 2001 September 16
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- ******************************************************************************
- **
- ** This header file (together with is companion C source-code file
- ** "os.c") attempt to abstract the underlying operating system so that
- ** the SQLite library will work on both POSIX and windows systems.
- **
- ** This header file is #include-ed by sqliteInt.h and thus ends up
- ** being included by every source file.
- */
- #ifndef _SQLITE_OS_H_
- #define _SQLITE_OS_H_
- /*
- ** Figure out if we are dealing with Unix, Windows, or some other
- ** operating system. After the following block of preprocess macros,
- ** all of SQLITE_OS_UNIX, SQLITE_OS_WIN, SQLITE_OS_OS2, and SQLITE_OS_OTHER
- ** will defined to either 1 or 0. One of the four will be 1. The other
- ** three will be 0.
- */
- #if defined(SQLITE_OS_OTHER)
- # if SQLITE_OS_OTHER==1
- # undef SQLITE_OS_UNIX
- # define SQLITE_OS_UNIX 0
- # undef SQLITE_OS_WIN
- # define SQLITE_OS_WIN 0
- # undef SQLITE_OS_OS2
- # define SQLITE_OS_OS2 0
- # else
- # undef SQLITE_OS_OTHER
- # endif
- #endif
- #if !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_OTHER)
- # define SQLITE_OS_OTHER 0
- # ifndef SQLITE_OS_WIN
- # if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__)
- # define SQLITE_OS_WIN 1
- # define SQLITE_OS_UNIX 0
- # define SQLITE_OS_OS2 0
- # elif defined(__EMX__) || defined(_OS2) || defined(OS2) || defined(_OS2_) || defined(__OS2__)
- # define SQLITE_OS_WIN 0
- # define SQLITE_OS_UNIX 0
- # define SQLITE_OS_OS2 1
- # else
- # define SQLITE_OS_WIN 0
- # define SQLITE_OS_UNIX 1
- # define SQLITE_OS_OS2 0
- # endif
- # else
- # define SQLITE_OS_UNIX 0
- # define SQLITE_OS_OS2 0
- # endif
- #else
- # ifndef SQLITE_OS_WIN
- # define SQLITE_OS_WIN 0
- # endif
- #endif
- /*
- ** Define the maximum size of a temporary filename
- */
- #if SQLITE_OS_WIN
- # include <windows.h>
- # define SQLITE_TEMPNAME_SIZE (MAX_PATH+50)
- #elif SQLITE_OS_OS2
- # if (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && defined(OS2_HIGH_MEMORY)
- # include <os2safe.h> /* has to be included before os2.h for linking to work */
- # endif
- # define INCL_DOSDATETIME
- # define INCL_DOSFILEMGR
- # define INCL_DOSERRORS
- # define INCL_DOSMISC
- # define INCL_DOSPROCESS
- # define INCL_DOSMODULEMGR
- # define INCL_DOSSEMAPHORES
- # include <os2.h>
- # include <uconv.h>
- # define SQLITE_TEMPNAME_SIZE (CCHMAXPATHCOMP)
- #else
- # define SQLITE_TEMPNAME_SIZE 200
- #endif
- /*
- ** Determine if we are dealing with Windows NT.
- **
- ** We ought to be able to determine if we are compiling for win98 or winNT
- ** using the _WIN32_WINNT macro as follows:
- **
- ** #if defined(_WIN32_WINNT)
- ** # define SQLITE_OS_WINNT 1
- ** #else
- ** # define SQLITE_OS_WINNT 0
- ** #endif
- **
- ** However, vs2005 does not set _WIN32_WINNT by default, as it ought to,
- ** so the above test does not work. We'll just assume that everything is
- ** winNT unless the programmer explicitly says otherwise by setting
- ** SQLITE_OS_WINNT to 0.
- */
- #if SQLITE_OS_WIN && !defined(SQLITE_OS_WINNT)
- # define SQLITE_OS_WINNT 1
- #endif
- /*
- ** Determine if we are dealing with WindowsCE - which has a much
- ** reduced API.
- */
- #if defined(_WIN32_WCE)
- # define SQLITE_OS_WINCE 1
- #else
- # define SQLITE_OS_WINCE 0
- #endif
- /* If the SET_FULLSYNC macro is not defined above, then make it
- ** a no-op
- */
- #ifndef SET_FULLSYNC
- # define SET_FULLSYNC(x,y)
- #endif
- /*
- ** The default size of a disk sector
- */
- #ifndef SQLITE_DEFAULT_SECTOR_SIZE
- # define SQLITE_DEFAULT_SECTOR_SIZE 4096
- #endif
- /*
- ** Temporary files are named starting with this prefix followed by 16 random
- ** alphanumeric characters, and no file extension. They are stored in the
- ** OS's standard temporary file directory, and are deleted prior to exit.
- ** If sqlite is being embedded in another program, you may wish to change the
- ** prefix to reflect your program's name, so that if your program exits
- ** prematurely, old temporary files can be easily identified. This can be done
- ** using -DSQLITE_TEMP_FILE_PREFIX=myprefix_ on the compiler command line.
- **
- ** 2006-10-31: The default prefix used to be "sqlite_". But then
- ** Mcafee started using SQLite in their anti-virus product and it
- ** started putting files with the "sqlite" name in the c:/temp folder.
- ** This annoyed many windows users. Those users would then do a
- ** Google search for "sqlite", find the telephone numbers of the
- ** developers and call to wake them up at night and complain.
- ** For this reason, the default name prefix is changed to be "sqlite"
- ** spelled backwards. So the temp files are still identified, but
- ** anybody smart enough to figure out the code is also likely smart
- ** enough to know that calling the developer will not help get rid
- ** of the file.
- */
- #ifndef SQLITE_TEMP_FILE_PREFIX
- # define SQLITE_TEMP_FILE_PREFIX "etilqs_"
- #endif
- /*
- ** The following values may be passed as the second argument to
- ** sqlite3OsLock(). The various locks exhibit the following semantics:
- **
- ** SHARED: Any number of processes may hold a SHARED lock simultaneously.
- ** RESERVED: A single process may hold a RESERVED lock on a file at
- ** any time. Other processes may hold and obtain new SHARED locks.
- ** PENDING: A single process may hold a PENDING lock on a file at
- ** any one time. Existing SHARED locks may persist, but no new
- ** SHARED locks may be obtained by other processes.
- ** EXCLUSIVE: An EXCLUSIVE lock precludes all other locks.
- **
- ** PENDING_LOCK may not be passed directly to sqlite3OsLock(). Instead, a
- ** process that requests an EXCLUSIVE lock may actually obtain a PENDING
- ** lock. This can be upgraded to an EXCLUSIVE lock by a subsequent call to
- ** sqlite3OsLock().
- */
- #define NO_LOCK 0
- #define SHARED_LOCK 1
- #define RESERVED_LOCK 2
- #define PENDING_LOCK 3
- #define EXCLUSIVE_LOCK 4
- /*
- ** File Locking Notes: (Mostly about windows but also some info for Unix)
- **
- ** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
- ** those functions are not available. So we use only LockFile() and
- ** UnlockFile().
- **
- ** LockFile() prevents not just writing but also reading by other processes.
- ** A SHARED_LOCK is obtained by locking a single randomly-chosen
- ** byte out of a specific range of bytes. The lock byte is obtained at
- ** random so two separate readers can probably access the file at the
- ** same time, unless they are unlucky and choose the same lock byte.
- ** An EXCLUSIVE_LOCK is obtained by locking all bytes in the range.
- ** There can only be one writer. A RESERVED_LOCK is obtained by locking
- ** a single byte of the file that is designated as the reserved lock byte.
- ** A PENDING_LOCK is obtained by locking a designated byte different from
- ** the RESERVED_LOCK byte.
- **
- ** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
- ** which means we can use reader/writer locks. When reader/writer locks
- ** are used, the lock is placed on the same range of bytes that is used
- ** for probabilistic locking in Win95/98/ME. Hence, the locking scheme
- ** will support two or more Win95 readers or two or more WinNT readers.
- ** But a single Win95 reader will lock out all WinNT readers and a single
- ** WinNT reader will lock out all other Win95 readers.
- **
- ** The following #defines specify the range of bytes used for locking.
- ** SHARED_SIZE is the number of bytes available in the pool from which
- ** a random byte is selected for a shared lock. The pool of bytes for
- ** shared locks begins at SHARED_FIRST.
- **
- ** The same locking strategy and
- ** byte ranges are used for Unix. This leaves open the possiblity of having
- ** clients on win95, winNT, and unix all talking to the same shared file
- ** and all locking correctly. To do so would require that samba (or whatever
- ** tool is being used for file sharing) implements locks correctly between
- ** windows and unix. I'm guessing that isn't likely to happen, but by
- ** using the same locking range we are at least open to the possibility.
- **
- ** Locking in windows is manditory. For this reason, we cannot store
- ** actual data in the bytes used for locking. The pager never allocates
- ** the pages involved in locking therefore. SHARED_SIZE is selected so
- ** that all locks will fit on a single page even at the minimum page size.
- ** PENDING_BYTE defines the beginning of the locks. By default PENDING_BYTE
- ** is set high so that we don't have to allocate an unused page except
- ** for very large databases. But one should test the page skipping logic
- ** by setting PENDING_BYTE low and running the entire regression suite.
- **
- ** Changing the value of PENDING_BYTE results in a subtly incompatible
- ** file format. Depending on how it is changed, you might not notice
- ** the incompatibility right away, even running a full regression test.
- ** The default location of PENDING_BYTE is the first byte past the
- ** 1GB boundary.
- **
- */
- #ifdef SQLITE_OMIT_WSD
- # define PENDING_BYTE (0x40000000)
- #else
- # define PENDING_BYTE sqlite3PendingByte
- #endif
- #define RESERVED_BYTE (PENDING_BYTE+1)
- #define SHARED_FIRST (PENDING_BYTE+2)
- #define SHARED_SIZE 510
- /*
- ** Wrapper around OS specific sqlite3_os_init() function.
- */
- SQLITE_PRIVATE int sqlite3OsInit(void);
- /*
- ** Functions for accessing sqlite3_file methods
- */
- SQLITE_PRIVATE int sqlite3OsClose(sqlite3_file*);
- SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file*, void*, int amt, i64 offset);
- SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file*, const void*, int amt, i64 offset);
- SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file*, i64 size);
- SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file*, int);
- SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file*, i64 *pSize);
- SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file*, int);
- SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file*, int);
- SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut);
- SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file*,int,void*);
- SQLITE_PRIVATE void sqlite3OsFileControlHint(sqlite3_file*,int,void*);
- #define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
- SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
- SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
- SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
- SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int, int, int);
- SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id);
- SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int);
- /*
- ** Functions for accessing sqlite3_vfs methods
- */
- SQLITE_PRIVATE int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
- SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
- SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut);
- SQLITE_PRIVATE int sqlite3OsFullPathname(sqlite3_vfs *, const char *, int, char *);
- #ifndef SQLITE_OMIT_LOAD_EXTENSION
- SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
- SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *, int, char *);
- SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *, void *, const char *))(void);
- SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *, void *);
- #endif /* SQLITE_OMIT_LOAD_EXTENSION */
- SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
- SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *, int);
- SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *, sqlite3_int64*);
- /*
- ** Convenience functions for opening and closing files using
- ** sqlite3_malloc() to obtain space for the file-handle structure.
- */
- SQLITE_PRIVATE int sqlite3OsOpenMalloc(sqlite3_vfs *, const char *, sqlite3_file **, int,int*);
- SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *);
- #endif /* _SQLITE_OS_H_ */
- /************** End of os.h **************************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /************** Include mutex.h in the middle of sqliteInt.h *****************/
- /************** Begin file mutex.h *******************************************/
- /*
- ** 2007 August 28
- **
- ** The author disclaims copyright to this source code. In place of
- ** a legal notice, here is a blessing:
- **
- ** May you do good and not evil.
- ** May you find forgiveness for yourself and forgive others.
- ** May you share freely, never taking more than you give.
- **
- *************************************************************************
- **
- ** This file contains the common header for all mutex implementations.
- ** The sqliteInt.h header #includes this file so that it is available
- ** to all source files. We break it out in an effort to keep the code
- ** better organized.
- **
- ** NOTE: source files should *not* #include this header file directly.
- ** Source files should #include the sqliteInt.h file and let that file
- ** include this one indirectly.
- */
- /*
- ** Figure out what version of the code to use. The choices are
- **
- ** SQLITE_MUTEX_OMIT No mutex logic. Not even stubs. The
- ** mutexes implemention cannot be overridden
- ** at start-time.
- **
- ** SQLITE_MUTEX_NOOP For single-threaded applications. No
- ** mutual exclusion is provided. But this
- ** implementation can be overridden at
- ** start-time.
- **
- ** SQLITE_MUTEX_PTHREADS For multi-threaded applications on Unix.
- **
- ** SQLITE_MUTEX_W32 For multi-threaded applications on Win32.
- **
- ** SQLITE_MUTEX_OS2 For multi-threaded applications on OS/2.
- */
- #if !SQLITE_THREADSAFE
- # define SQLITE_MUTEX_OMIT
- #endif
- #if SQLITE_THREADSAFE && !defined(SQLITE_MUTEX_NOOP)
- # if SQLITE_OS_UNIX
- # define SQLITE_MUTEX_PTHREADS
- # elif SQLITE_OS_WIN
- # define SQLITE_MUTEX_W32
- # elif SQLITE_OS_OS2
- # define SQLITE_MUTEX_OS2
- # else
- # define SQLITE_MUTEX_NOOP
- # endif
- #endif
- #ifdef SQLITE_MUTEX_OMIT
- /*
- ** If this is a no-op implementation, implement everything as macros.
- */
- #define sqlite3_mutex_alloc(X) ((sqlite3_mutex*)8)
- #define sqlite3_mutex_free(X)
- #define sqlite3_mutex_enter(X)
- #define sqlite3_mutex_try(X) SQLITE_OK
- #define sqlite3_mutex_leave(X)
- #define sqlite3_mutex_held(X) ((void)(X),1)
- #define sqlite3_mutex_notheld(X) ((void)(X),1)
- #define sqlite3MutexAlloc(X) ((sqlite3_mutex*)8)
- #define sqlite3MutexInit() SQLITE_OK
- #define sqlite3MutexEnd()
- #define MUTEX_LOGIC(X)
- #else
- #define MUTEX_LOGIC(X) X
- #endif /* defined(SQLITE_MUTEX_OMIT) */
- /************** End of mutex.h ***********************************************/
- /************** Continuing where we left off in sqliteInt.h ******************/
- /*
- ** Each database file to be accessed by the system is an instance
- ** of the following structure. There are normally two of these structures
- ** in the sqlite.aDb[] array. aDb[0] is the main database file and
- ** aDb[1] is the database file used to hold temporary tables. Additional
- ** databases may be attached.
- */
- struct Db {
- char *zName; /* Name of this database */
- Btree *pBt; /* The B*Tree structure for this database file */
- u8 inTrans; /* 0: not writable. 1: Transaction. 2: Checkpoint */
- u8 safety_level; /* How aggressive at syncing data to disk */
- Schema *pSchema; /* Pointer to database schema (possibly shared) */
- };
- /*
- ** An instance of the following structure stores a database schema.
- **
- ** Most Schema objects are associated with a Btree. The exception is
- ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
- ** In shared cache mode, a single Schema object can be shared by multiple
- ** Btrees that refer to the same underlying BtShared object.
- **
- ** Schema objects are automatically deallocated when the last Btree that
- ** references them is destroyed. The TEMP Schema is manually freed by
- ** sqlite3_close().
- *
- ** A thread must be holding a mutex on the corresponding Btree in order
- ** to access Schema content. This implies that the thread must also be
- ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
- ** For a TEMP Schema, only the connection mutex is required.
- */
- struct Schema {
- int schema_cookie; /* Database schema version number for this file */
- int iGeneration; /* Generation counter. Incremented with each change */
- Hash tblHash; /* All tables indexed by name */
- Hash idxHash; /* All (named) indices indexed by name */
- Hash trigHash; /* All triggers indexed by name */
- Hash fkeyHash; /* All foreign keys by referenced table name */
- Table *pSeqTab; /* The sqlite_sequence table used by AUTOINCREMENT */
- u8 file_format; /* Schema format version for this file */
- u8 enc; /* Text encoding used by this database */
- u16 flags; /* Flags associated with this schema */
- int cache_size; /* Number of pages to use in the cache */
- };
- /*
- ** These macros can be used to test, set, or clear bits in the
- ** Db.pSchema->flags field.
- */
- #define DbHasProperty(D,I,P) (((D)->aDb[I].pSchema->flags&(P))==(P))
- #define DbHasAnyProperty(D,I,P) (((D)->aDb[I].pSchema->flags&(P))!=0)
- #define DbSetProperty(D,I,P) (D)->aDb[I].pSchema->flags|=(P)
- #define DbClearProperty(D,I,P) (D)->aDb[I].pSchema->flags&=~(P)
- /*
- ** Allowed values for the DB.pSchema->flags field.
- **
- ** The DB_SchemaLoaded flag is set after the database schema has been
- ** read into internal hash tables.
- **
- ** DB_UnresetViews means that one or more views have column names that
- ** have been filled out. If the schema changes, these column names might
- ** changes and so the view will need to be reset.
- */
- #define DB_SchemaLoaded 0x0001 /* The schema has been loaded */
- #define DB_UnresetViews 0x0002 /* Some views have defined column names */
- #define DB_Empty 0x0004 /* The file is empty (length 0 bytes) */
- /*
- ** The number of different kinds of things that can be limited
- ** using the sqlite3_limit() interface.
- */
- #define SQLITE_N_LIMIT (SQLITE_LIMIT_TRIGGER_DEPTH+1)
- /*
- ** Lookaside malloc is a set of fixed-size buffers that can be used
- ** to satisfy small transient memory allocation requests for objects
- ** associated with a particular database connection. The use of
- ** lookaside malloc provides a significant performance enhancement
- ** (approx 10%) by avoiding numerous malloc/free requests while parsing
- ** SQL statements.
- **
- ** The Lookaside structure holds configuration information about the
- ** lookaside malloc subsystem. Each available memory allocation in
- ** the lookaside subsystem is stored on a linked list of LookasideSlot
- ** objects.
- **
- ** Lookaside allocations are only allowed for objects that are associated
- ** with a particular database connection. Hence, schema information cannot
- ** be stored in lookaside because in shared cache mode the schema information
- ** is shared by multiple database connections. Therefore, while parsing
- ** schema information, the Lookaside.bEnabled flag is cleared so that
- ** lookaside allocations are not used to construct the schema objects.
- */
- struct Lookaside {
- u16 sz; /* Size of each buffer in bytes */
- u8 bEnabled; /* False to disable new lookaside allocations */
- u8 bMalloced; /* True if pStart obtained from sqlite3_malloc() */
- int nOut; /* Number of buffers currently checked out */
- int mxOut; /* Highwater mark for nOut */
- int anStat[3]; /* 0: hits. 1: size misses. 2: full misses */
- LookasideSlot *pFree; /* List of available buffers */
- void *pStart; /* First byte of available memory space */
- void *pEnd; /* First byte past end of available space */
- };
- struct LookasideSlot {
- LookasideSlot *pNext; /* Next buffer in the list of free buffers */
- };
- /*
- ** A hash table for function definitions.
- **
- ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
- ** Collisions are on the FuncDef.pHash chain.
- */
- struct FuncDefHash {
- FuncDef *a[23]; /* Hash table for functions */
- };
- /*
- ** Each database connection is an instance of the following structure.
- */
- struct sqlite3 {
- sqlite3_vfs *pVfs; /* OS Interface */
- struct Vdbe *pVdbe; /* List of active virtual machines */
- CollSeq *pDfltColl; /* The default collating sequence (BINARY) */
- sqlite3_mutex *mutex; /* Connection mutex */
- Db *aDb; /* All backends */
- int nDb; /* Number of backends currently in use */
- int flags; /* Miscellaneous flags. See below */
- i64 lastRowid; /* ROWID of most recent insert (see above) */
- unsigned int openFlags; /* Flags passed to sqlite3_vfs.xOpen() */
- int errCode; /* Most recent error code (SQLITE_*) */
- int errMask; /* & result codes with this before returning */
- u8 autoCommit; /* The auto-commit flag. */
- u8 temp_store; /* 1: file 2: memory 0: default */
- u8 mallocFailed; /* True if we have seen a malloc failure */
- u8 dfltLockMode; /* Default locking-mode for attached dbs */
- signed char nextAutovac; /* Autovac setting after VACUUM if >=0 */
- u8 suppressErr; /* Do not issue error messages if true */
- u8 vtabOnConflict; /* Value to return for s3_vtab_on_conflict() */
- u8 isTransactionSavepoint; /* True if the outermost savepoint is a TS */
- int nextPagesize; /* Pagesize after VACUUM if >0 */
- u32 magic; /* Magic number for detect library misuse */
- int nChange; /* Value returned by sqlite3_changes() */
- int nTotalChange; /* Value returned by sqlite3_total_changes() */
- int aLimit[SQLITE_N_LIMIT]; /* Limits */
- struct sqlite3InitInfo { /* Information used during initialization */
- int newTnum; /* Rootpage of table being initialized */
- u8 iDb; /* Which db file is being initialized */
- u8 busy; /* TRUE if currently initializing */
- u8 orphanTrigger; /* Last statement is orphaned TEMP trigger */
- } init;
- int activeVdbeCnt; /* Number of VDBEs currently executing */
- int writeVdbeCnt; /* Number of active VDBEs that are writing */
- int vdbeExecCnt; /* Number of nested calls to VdbeExec() */
- int nExtension; /* Number of loaded extensions */
- void **aExtension; /* Array of shared library handles */
- void (*xTrace)(void*,const char*); /* Trace function */
- void *pTraceArg; /* Argument to the trace function */
- void (*xProfile)(void*,const char*,u64); /* Profiling function */
- void *pProfileArg; /* Argument to profile function */
- void *pCommitArg; /* Argument to xCommitCallback() */
- int (*xCommitCallback)(void*); /* Invoked at every commit. */
- void *pRollbackArg; /* Argument to xRollbackCallback() */
- void (*xRollbackCallback)(void*); /* Invoked at every commit. */
- void *pUpdateArg;
- void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
- #ifndef SQLITE_OMIT_WAL
- int (*xWalCallback)(void *, sqlite3 *, const char *, int);
- void *pWalArg;
- #endif
- void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
- void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
- void *pCollNeededArg;
- sqlite3_value *pErr; /* Most recent error message */
- char *zErrMsg; /* Most recent error message (UTF-8 encoded) */
- char *zErrMsg16; /* Most recent error message (UTF-16 encoded) */
- union {
- volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
- double notUsed1; /* Spacer */
- } u1;
- Lookaside lookaside; /* Lookaside malloc configuration */
- #ifndef SQLITE_OMIT_AUTHORIZATION
- int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
- /* Access authorization function */
- void *pAuthArg; /* 1st argument to the access auth function */
- #endif
- #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
- int (*xProgress)(void *); /* The progress callback */
- void *pProgressArg; /* Argument to the progress callback */
- int nProgressOps; /* Number of opcodes for progress callback */
- #endif
- #ifndef SQLITE_OMIT_VIRTUALTABLE
- int nVTrans; /* Allocated size of aVTrans */
- Hash aModule; /* populated by sqlite3_create_module() */
- VtabCtx *pVtabCtx; /* Context for active vtab connect/create */
- VTable **aVTrans; /* Virtual tables with open transactions */
- VTable *pDisconnect; /* Disconnect these in next sqlite3_prepare() */
- #endif
- FuncDefHash aFunc; /* Hash table of connection functions */
- Hash aCollSeq; /* All collating sequences */
- BusyHandler busyHandler; /* Busy callback */
- Db aDbStatic[2]; /* Static space for the 2 default backends */
- Savepoint *pSavepoint; /* List of active savepoints */
- int busyTimeout; /* Busy handler timeout, in msec */
- int nSavepoint; /* Number of non-transaction savepoints */
- int nStatement; /* Number of nested statement-transactions */
- i64 nDeferredCons; /* Net deferred constraints this transaction. */
- int *pnBytesFreed; /* If not NULL, increment this in DbFree() */
- #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
- /* The following variables are all protected by the STATIC_MASTER
- ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
- **
- ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
- ** unlock so that it can proceed.
- **
- ** When X.pBlockingConnection==Y, that means that something that X tried
- ** tried to do recently failed with an SQLITE_LOCKED error due to locks
- ** held by Y.
- */
- sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
- sqlite3 *pUnlockConnection; /* Connection to watch for unlock */
- void *pUnlockArg; /* Argument to xUnlockNotify */
- void (*xUnlockNotify)(void **, int); /* Unlock notify callback */
- sqlite3 *pNextBlocked; /* Next in list of all blocked connections */
- #endif
- };
- /*
- ** A macro to discover the encoding of a database.
- */
- #define ENC(db) ((db)->aDb[0].pSchema->enc)
- /*
- ** Possible values for the sqlite3.flags.
- */
- #define SQLITE_VdbeTrace 0x00000100 /* True to trace VDBE execution */
- #define SQLITE_InternChanges 0x00000200 /* Uncommitted Hash table changes */
- #define SQLITE_FullColNames 0x00000400 /* Show full column names on SELECT */
- #define SQLITE_ShortColNames 0x00000800 /* Show short columns names */
- #define SQLITE_CountRows 0x00001000 /* Count rows changed by INSERT, */
- /* DELETE, or UPDATE and return */
- /* the count using a callback. */
- #define SQLITE_NullCallback 0x00002000 /* Invoke the callback once if the */
- /* result set is empty */
- #define SQLITE_SqlTrace 0x00004000 /* Debug print SQL as it executes */
- #define SQLITE_VdbeListing 0x00008000 /* Debug listings of VDBE programs */
- #define SQLITE_WriteSchema 0x00010000 /* OK to update SQLITE_MASTER */
- /* 0x00020000 Unused */
- #define SQLITE_IgnoreChecks 0x00040000 /* Do not enforce check constraints */
- #define SQLITE_ReadUncommitted 0x0080000 /* For shared-cache mode */
- #define SQLITE_LegacyFileFmt 0x00100000 /* Create new databases in format 1 */
- #define SQLITE_FullFSync 0x00200000 /* Use full fsync on the backend */
- #define SQLITE_CkptFullFSync 0x00400000 /* Use full fsync for checkpoint */
- #define SQLITE_RecoveryMode 0x00800000 /* Ignore schema errors */
- #define SQLITE_ReverseOrder 0x01000000 /* Reverse unordered SELECTs */
- #define SQLITE_RecTriggers 0x02000000 /* Enable recursive triggers */
- #define SQLITE_ForeignKeys 0x04000000 /* Enforce foreign key constraints */
- #define SQLITE_AutoIndex 0x08000000 /* Enable automatic indexes */
- #define SQLITE_PreferBuiltin 0x10000000 /* Preference to built-in funcs */
- #define SQLITE_LoadExtension 0x20000000 /* Enable load_extension */
- #define SQLITE_EnableTrigger 0x40000000 /* True to enable triggers */
- /*
- ** Bits of the sqlite3.flags field that are used by the
- ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface.
- ** These must be the low-order bits of the flags field.
- */
- #define SQLITE_QueryFlattener 0x01 /* Disable query flattening */
- #define SQLITE_ColumnCache 0x02 /* Disable the column cache */
- #define SQLITE_IndexSort 0x04 /* Disable indexes for sorting */
- #define SQLITE_IndexSearch 0x08 /* Disable indexes for searching */
- #define SQLITE_IndexCover 0x10 /* Disable index covering table */
- #define SQLITE_GroupByOrder 0x20 /* Disable GROUPBY cover of ORDERBY */
- #define SQLITE_FactorOutConst 0x40 /* Disable factoring out constants */
- #define SQLITE_IdxRealAsInt 0x80 /* Store REAL as INT in indices */
- #define SQLITE_DistinctOpt 0x80 /* DISTINCT using indexes */
- #define SQLITE_OptMask 0xff /* Mask of all disablable opts */
- /*
- ** Possible values for the sqlite.magic field.
- ** The numbers are obtained at random and have no special meaning, other
- ** than being distinct from one another.
- */
- #define SQLITE_MAGIC_OPEN 0xa029a697 /* Database is open */
- #define SQLITE_MAGIC_CLOSED 0x9f3c2d33 /* Database is closed */
- #define SQLITE_MAGIC_SICK 0x4b771290 /* Error and awaiting close */
- #define SQLITE_MAGIC_BUSY 0xf03b7906 /* Database currently in use */
- #define SQLITE_MAGIC_ERROR 0xb5357930 /* An SQLITE_MISUSE error occurred */
- /*
- ** Each SQL function is defined by an instance of the following
- ** structure. A pointer to this structure is stored in the sqlite.aFunc
- ** hash table. When multiple functions have the same name, the hash table
- ** points to a linked list of these structures.
- */
- struct FuncDef {
- i16 nArg; /* Number of arguments. -1 means unlimited */
- u8 iPrefEnc; /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
- u8 flags; /* Some combination of SQLITE_FUNC_* */
- void *pUserData; /* User data parameter */
- FuncDef *pNext; /* Next function with same name */
- void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
- void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
- void (*xFinalize)(sqlite3_context*); /* Aggregate finalizer */
- char *zName; /* SQL name of the function. */
- FuncDef *pHash; /* Next with a different name but the same hash */
- FuncDestructor *pDestructor; /* Reference counted destructor function */
- };
- /*
- ** This structure encapsulates a user-function destructor callback (as
- ** configured using create_function_v2()) and a reference counter. When
- ** create_function_v2() is called to create a function with a destructor,
- ** a single object of this type is allocated. FuncDestructor.nRef is set to
- ** the number of FuncDef objects created (either 1 or 3, depending on whether
- ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
- ** member of each of the new FuncDef objects is set to point to the allocated
- ** FuncDestructor.
- **
- ** Thereafter, when one of the FuncDef objects is deleted, the reference
- ** count on this object is decremented. When it reaches 0, the destructor
- ** is invoked and the FuncDestructor structure freed.
- */
- struct FuncDestructor {
- int nRef;
- void (*xDestroy)(void *);
- void *pUserData;
- };
- /*
- ** Possible values for FuncDef.flags
- */
- #define SQLITE_FUNC_LIKE 0x01 /* Candidate for the LIKE optimization */
- #define SQLITE_FUNC_CASE 0x02 /* Case-sensitive LIKE-type function */
- #define SQLITE_FUNC_EPHEM 0x04 /* Ephemeral. Delete with VDBE */
- #define SQLITE_FUNC_NEEDCOLL 0x08 /* sqlite3GetFuncCollSeq() might be called */
- #define SQLITE_FUNC_COUNT 0x20 /* Built-in count(*) aggregate */
- #define SQLITE_FUNC_COALESCE 0x40 /* Built-in coalesce() or ifnull() function */
- /*
- ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
- ** used to create the initializers for the FuncDef structures.
- **
- ** FUNCTION(zName, nArg, iArg, bNC, xFunc)
- ** Used to create a scalar function definition of a function zName
- ** implemented by C function xFunc that accepts nArg arguments. The
- ** value passed as iArg is cast to a (void*) and made available
- ** as the user-data (sqlite3_user_data()) for the function. If
- ** argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
- **
- ** AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
- ** Used to create an aggregate function definition implemented by
- ** the C functions xStep and xFinal. The first four parameters
- ** are interpreted in the same way as the first 4 parameters to
- ** FUNCTION().
- **
- ** LIKEFUNC(zName, nArg, pArg, flags)
- ** Used to create a scalar function definition of a function zName
- ** that accepts nArg arguments and is implemented by a call to C
- ** function likeFunc. Argument pArg is cast to a (void *) and made
- ** available as the function user-data (sqlite3_user_data()). The
- ** FuncDef.flags variable is set to the value passed as the flags
- ** parameter.
- */
- #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
- {nArg, SQLITE_UTF8, bNC*SQLITE_FUNC_NEEDCOLL, \
- SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
- #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
- {nArg, SQLITE_UTF8, bNC*SQLITE_FUNC_NEEDCOLL, \
- pArg, 0, xFunc, 0, 0, #zName, 0, 0}
- #define LIKEFUNC(zName, nArg, arg, flags) \
- {nArg, SQLITE_UTF8, flags, (void *)arg, 0, likeFunc, 0, 0, #zName, 0, 0}
- #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
- {nArg, SQLITE_UTF8, nc*SQLITE_FUNC_NEEDCOLL, \
- SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}
- /*
- ** All current savepoints are stored in a linked list starting at
- ** sqlite3.pSavepoint. The first element in the list is the most recently
- ** opened savepoint. Savepoints are added to the list by the vdbe
- ** OP_Savepoint instruction.
- */
- struct Savepoint {
- char *zName; /* Savepoint name (nul-terminated) */
- i64 nDeferredCons; /* Number of deferred fk violations */
- Savepoint *pNext; /* Parent savepoint (if any) */
- };
- /*
- ** The following are used as the second parameter to sqlite3Savepoint(),
- ** and as the P1 argument to the OP_Savepoint instruction.
- */
- #define SAVEPOINT_BEGIN 0
- #define SAVEPOINT_RELEASE 1
- #define SAVEPOINT_ROLLBACK 2
- /*
- ** Each SQLite module (virtual table definition) is defined by an
- ** instance of the following structure, stored in the sqlite3.aModule
- ** hash table.
- */
- struct Module {
- const sqlite3_module *pModule; /* Callback pointers */
- const char *zName; /* Name passed to create_module() */
- void *pAux; /* pAux passed to create_module() */
- void (*xDestroy)(void *); /* Module destructor function */
- };
- /*
- ** information about each column of an SQL table is held in an instance
- ** of this structure.
- */
- struct Column {
- char *zName; /* Name of this column */
- Expr *pDflt; /* Default value of this column */
- char *zDflt; /* Original text of the default value */
- char *zType; /* Data type for this column */
- char *zColl; /* Collating sequence. If NULL, use the default */
- u8 notNull; /* True if there is a NOT NULL constraint */
- u8 isPrimKey; /* True if this column is part of the PRIMARY KEY */
- char affinity; /* One of the SQLITE_AFF_... values */
- #ifndef SQLITE_OMIT_VIRTUALTABLE
- u8 isHidden; /* True if this column is 'hidden' */
- #endif
- };
- /*
- ** A "Collating Sequence" is defined by an instance of the following
- ** structure. Conceptually, a collating sequence consists of a name and
- ** a comparison routine that defines the order of that sequence.
- **
- ** There may two separate implementations of the collation function, one
- ** that processes text in UTF-8 encoding (CollSeq.xCmp) and another that
- ** processes text encoded in UTF-16 (CollSeq.xCmp16), using the machine
- ** native byte order. When a collation sequence is invoked, SQLite selects
- ** the version that will require the least expensive encoding
- ** translations, if any.
- **
- ** The CollSeq.pUser member variable is an extra parameter that passed in
- ** as the first argument to the UTF-8 comparison function, xCmp.
- ** CollSeq.pUser16 is the equivalent for the UTF-16 comparison function,
- ** xCmp16.
- **
- ** If both CollSeq.xCmp and CollSeq.xCmp16 are NULL, it means that the
- ** collating sequence is undefined. Indices built on an undefined
- ** collating sequence may not be read or written.
- */
- struct CollSeq {
- char *zName; /* Name of the collating sequence, UTF-8 encoded */
- u8 enc; /* Text encoding handled by xCmp() */
- void *pUser; /* First argument to xCmp() */
- int (*xCmp)(void*,int, const void*, int, const void*);
- void (*xDel)(void*); /* Destructor for pUser */
- };
- /*
- ** A sort order can be either ASC or DESC.
- */
- #define SQLITE_SO_ASC 0 /* Sort in ascending order */
- #define SQLITE_SO_DESC 1 /* Sort in ascending order */
- /*
- ** Column affinity types.
- **
- ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
- ** 't' for SQLITE_AFF_TEXT. But we can save a little space and improve
- ** the speed a little by numbering the values consecutively.
- **
- ** But rather than start with 0 or 1, we begin with 'a'. That way,
- ** when multiple affinity types are concatenated into a string and
- ** used as the P4 operand, they will be more readable.
- **
- ** Note also that the numeric types are grouped together so that testing
- ** for a numeric type is a single comparison.
- */
- #define SQLITE_AFF_TEXT 'a'
- #define SQLITE_AFF_NONE 'b'
- #define SQLITE_AFF_NUMERIC 'c'
- #define SQLITE_AFF_INTEGER 'd'
- #define SQLITE_AFF_REAL 'e'
- #define sqlite3IsNumericAffinity(X) ((X)>=SQLITE_AFF_NUMERIC)
- /*
- ** The SQLITE_AFF_MASK values masks off the significant bits of an
- ** affinity value.
- */
- #define SQLITE_AFF_MASK 0x67
- /*
- ** Additional bit values that can be ORed with an affinity without
- ** changing the affinity.
- */
- #define SQLITE_JUMPIFNULL 0x08 /* jumps if either operand is NULL */
- #define SQLITE_STOREP2 0x10 /* Store result in reg[P2] rather than jump */
- #define SQLITE_NULLEQ 0x80 /* NULL=NULL */
- /*
- ** An object of this type is created for each virtual table present in
- ** the database schema.
- **
- ** If the database schema is shared, then there is one instance of this
- ** structure for each database connection (sqlite3*) that uses the shared
- ** schema. This is because each database connection requires its own unique
- ** instance of the sqlite3_vtab* handle used to access the virtual table
- ** implementation. sqlite3_vtab* handles can not be shared between
- ** database connections, even when the rest of the in-memory database
- ** schema is shared, as the implementation often stores the database
- ** connection handle passed to it via the xConnect() or xCreate() method
- ** during initialization internally. This database connection handle may
- ** then be used by the virtual table implementation to access real tables
- ** within the database. So that they appear as part of the callers
- ** transaction, these accesses need to be made via the same database
- ** connection as that used to execute SQL operations on the virtual table.
- **
- ** All VTable objects that correspond to a single table in a shared
- ** database schema are initially stored in a linked-list pointed to by
- ** the Table.pVTable member variable of the corresponding Table object.
- ** When an sqlite3_prepare() operation is required to access the virtual
- ** table, it searches the list for the VTable that corresponds to the
- ** database connection doing the preparing so as to use the correct
- ** sqlite3_vtab* handle in the compiled query.
- **
- ** When an in-memory Table object is deleted (for example when the
- ** schema is being reloaded for some reason), the VTable objects are not
- ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
- ** immediately. Instead, they are moved from the Table.pVTable list to
- ** another linked list headed by the sqlite3.pDisconnect member of the
- ** corresponding sqlite3 structure. They are then deleted/xDisconnected
- ** next time a statement is prepared using said sqlite3*. This is done
- ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
- ** Refer to comments above function sqlite3VtabUnlockList() for an
- ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
- ** list without holding the corresponding sqlite3.mutex mutex.
- **
- ** The memory for objects of this type is always allocated by
- ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
- ** the first argument.
- */
- struct VTable {
- sqlite3 *db; /* Database connection associated with this table */
- Module *pMod; /* Pointer to module implementation */
- sqlite3_vtab *pVtab; /* Pointer to vtab instance */
- int nRef; /* Number of pointers to this structure */
- u8 bConstraint; /* True if constraints are supported */
- int iSavepoint; /* Depth of the SAVEPOINT stack */
- VTable *pNext; /* Next in linked list (see above) */
- };
- /*
- ** Each SQL table is represented in memory by an instance of the
- ** following structure.
- **
- ** Table.zName is the name of the table. The case of the original
- ** CREATE TABLE statement is stored, but case is not significant for
- ** comparisons.
- **
- ** Table.nCol is the number of columns in this table. Table.aCol is a
- ** pointer to an array of Column structures, one for each column.
- **
- ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
- ** the column that is that key. Otherwise Table.iPKey is negative. Note
- ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
- ** be set. An INTEGER PRIMARY KEY is used as the rowid for each row of
- ** the table. If a table has no INTEGER PRIMARY KEY, then a random rowid
- ** is generated for each row of the table. TF_HasPrimaryKey is set if
- ** the table has any PRIMARY KEY, INTEGER or otherwise.
- **
- ** Table.tnum is the page number for the root BTree page of the table in the
- ** database file. If Table.iDb is the index of the database table backend
- ** in sqlite.aDb[]. 0 is for the main database and 1 is for the file that
- ** holds temporary tables and indices. If TF_Ephemeral is set
- ** then the table is stored in a file that is automatically deleted
- ** when the VDBE cursor to the table is closed. In this case Table.tnum
- ** refers VDBE cursor number that holds the table open, not to the root
- ** page number. Transient tables are used to hold the results of a
- ** sub-query that appears instead of a real table name in the FROM clause
- ** of a SELECT statement.
- */
- struct Table {
- char *zName; /* Name of the table or view */
- int iPKey; /* If not negative, use aCol[iPKey] as the primary key */
- int nCol; /* Number of columns in this table */
- Column *aCol; /* Information about each column */
- Index *pIndex; /* List of SQL indexes on this table. */
- int tnum; /* Root BTree node for this table (see note above) */
- tRowcnt nRowEst; /* Estimated rows in table - from sqlite_stat1 table */
- Select *pSelect; /* NULL for tables. Points to definition if a view. */
- u16 nRef; /* Number of pointers to this Table */
- u8 tabFlags; /* Mask of TF_* values */
- u8 keyConf; /* What to do in case of uniqueness conflict on iPKey */
- FKey *pFKey; /* Linked list of all foreign keys in this table */
- char *zColAff; /* String defining the affinity of each column */
- #ifndef SQLITE_OMIT_CHECK
- Expr *pCheck; /* The AND of all CHECK constraints */
- #endif
- #ifndef SQLITE_OMIT_ALTERTABLE
- int addColOffset; /* Offset in CREATE TABLE stmt to add a new column */
- #endif
- #ifndef SQLITE_OMIT_VIRTUALTABLE
- VTable *pVTable; /* List of VTable objects. */
- int nModuleArg; /* Number of arguments to the module */
- char **azModuleArg; /* Text of all module args. [0] is module name */
- #endif
- Trigger *pTrigger; /* List of triggers stored in pSchema */
- Schema *pSchema; /* Schema that contains this table */
- Table *pNextZombie; /* Next on the Parse.pZombieTab list */
- };
- /*
- ** Allowed values for Tabe.tabFlags.
- */
- #define TF_Readonly 0x01 /* Read-only system table */
- #define TF_Ephemeral 0x02 /* An ephemeral table */
- #define TF_HasPrimaryKey 0x04 /* Table has a primary key */
- #define TF_Autoincrement 0x08 /* Integer primary key is autoincrement */
- #define TF_Virtual 0x10 /* Is a virtual table */
- /*
- ** Test to see whether or not a table is a virtual table. This is
- ** done as a macro so that it will be optimized out when virtual
- ** table support is omitted from the build.
- */
- #ifndef SQLITE_OMIT_VIRTUALTABLE
- # define IsVirtual(X) (((X)->tabFlags & TF_Virtual)!=0)
- # define IsHiddenColumn(X) ((X)->isHidden)
- #else
- # define IsVirtual(X) 0
- # define IsHiddenColumn(X) 0
- #endif
- /*
- ** Each foreign key constraint is an instance of the following structure.
- **
- ** A foreign key is associated with two tables. The "from" table is
- ** the table that contains the REFERENCES clause that creates the foreign
- ** key. The "to" table is the table that is named in the REFERENCES clause.
- ** Consider this example:
- **
- ** CREATE TABLE ex1(
- ** a INTEGER PRIMARY KEY,
- ** b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
- ** );
- **
- ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
- **
- ** Each REFERENCES clause generates an instance of the following structure
- ** which is attached to the from-table. The to-table need not exist when
- ** the from-table is created. The existence of the to-table is not checked.
- */
- struct FKey {
- Table *pFrom; /* Table containing the REFERENCES clause (aka: Child) */
- FKey *pNextFrom; /* Next foreign key in pFrom */
- char *zTo; /* Name of table that the key points to (aka: Parent) */
- FKey *pNextTo; /* Next foreign key on table named zTo */
- FKey *pPrevTo; /* Previous foreign key on table named zTo */
- int nCol; /* Number of columns in this key */
- /* EV: R-30323-21917 */
- u8 isDeferred; /* True if constraint checking is deferred till COMMIT */
- u8 aAction[2]; /* ON DELETE and ON UPDATE actions, respectively */
- Trigger *apTrigger[2]; /* Triggers for aAction[] actions */
- struct sColMap { /* Mapping of columns in pFrom to columns in zTo */
- int iFrom; /* Index of column in pFrom */
- char *zCol; /* Name of column in zTo. If 0 use PRIMARY KEY */
- } aCol[1]; /* One entry for each of nCol column s */
- };
- /*
- ** SQLite supports many different ways to resolve a constraint
- ** error. ROLLBACK processing means that a constraint violation
- ** causes the operation in process to fail and for the current transaction
- ** to be rolled back. ABORT processing means the operation in process
- ** fails and any prior changes from that one operation are backed out,
- ** but the transaction is not rolled back. FAIL processing means that
- ** the operation in progress stops and returns an error code. But prior
- ** changes due to the same operation are not backed out and no rollback
- ** occurs. IGNORE means that the particular row that caused the constraint
- ** error is not inserted or updated. Processing continues and no error
- ** is returned. REPLACE means that preexisting database rows that caused
- ** a UNIQUE constraint violation are removed so that the new insert or
- ** update can proceed. Processing continues and no error is reported.
- **
- ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
- ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
- ** same as ROLLBACK for DEFERRED keys. SETNULL means that the foreign
- ** key is set to NULL. CASCADE means that a DELETE or UPDATE of the
- ** referenced table row is propagated into the row that holds the
- ** foreign key.
- **
- ** The following symbolic values are used to record which type
- ** of action to take.
- */
- #define OE_None 0 /* There is no constraint to check */
- #define OE_Rollback 1 /* Fail the operation and rollback the transaction */
- #define OE_Abort 2 /* Back out changes but do no rollback transaction */
- #define OE_Fail 3 /* Stop the operation but leave all prior changes */
- #define OE_Ignore 4 /* Ignore the error. Do not do the INSERT or UPDATE */
- #define OE_Replace 5 /* Delete existing record, then do INSERT or UPDATE */
- #define OE_Restrict 6 /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
- #define OE_SetNull 7 /* Set the foreign key value to NULL */
- #define OE_SetDflt 8 /* Set the foreign key value to its default */
- #define OE_Cascade 9 /* Cascade the changes */
- #define OE_Default 99 /* Do whatever the default action is */
- /*
- ** An instance of the following structure is passed as the first
- ** argument to sqlite3VdbeKeyCompare and is used to control the
- ** comparison of the two index keys.
- */
- struct KeyInfo {
- sqlite3 *db; /* The database connection */
- u8 enc; /* Text encoding - one of the SQLITE_UTF* values */
- u16 nField; /* Number of entries in aColl[] */
- u8 *aSortOrder; /* Sort order for each column. May be NULL */
- CollSeq *aColl[1]; /* Collating sequence for each term of the key */
- };
- /*
- ** An instance of the following structure holds information about a
- ** single index record that has already been parsed out into individual
- ** values.
- **
- ** A record is an object that contains one or more fields of data.
- ** Records are used to store the content of a table row and to store
- ** the key of an index. A blob encoding of a record is created by
- ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
- ** OP_Column opcode.
- **
- ** This structure holds a record that has already been disassembled
- ** into its constituent fields.
- */
- struct UnpackedRecord {
- KeyInfo *pKeyInfo; /* Collation and sort-order information */
- u16 nField; /* Number of entries in apMem[] */
- u8 flags; /* Boolean settings. UNPACKED_... below */
- i64 rowid; /* Used by UNPACKED_PREFIX_SEARCH */
- Mem *aMem; /* Values */
- };
- /*
- ** Allowed values of UnpackedRecord.flags
- */
- #define UNPACKED_INCRKEY 0x01 /* Make this key an epsilon larger */
- #define UNPACKED_PREFIX_MATCH 0x02 /* A prefix match is considered OK */
- #define UNPACKED_PREFIX_SEARCH 0x04 /* Ignore final (rowid) field */
- /*
- ** Each SQL index is represented in memory by an
- ** instance of the following structure.
- **
- ** The columns of the table that are to be indexed are described
- ** by the aiColumn[] field of this structure. For example, suppose
- ** we have the following table and index:
- **
- ** CREATE TABLE Ex1(c1 int, c2 int, c3 text);
- ** CREATE INDEX Ex2 ON Ex1(c3,c1);
- **
- ** In the Table structure describing Ex1, nCol==3 because there are
- ** three columns in the table. In the Index structure describing
- ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
- ** The value of aiColumn is {2, 0}. aiColumn[0]==2 because the
- ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
- ** The second column to be indexed (c1) has an index of 0 in
- ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
- **
- ** The Index.onError field determines whether or not the indexed columns
- ** must be unique and what to do if they are not. When Index.onError=OE_None,
- ** it means this is not a unique index. Otherwise it is a unique index
- ** and the value of Index.onError indicate the which conflict resolution
- ** algorithm to employ whenever an attempt is made to insert a non-unique
- ** element.
- */
- struct Index {
- char *zName; /* Name of this index */
- int *aiColumn; /* Which columns are used by this index. 1st is 0 */
- tRowcnt *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
- Table *pTable; /* The SQL table being indexed */
- char *zColAff; /* String defining the affinity of each column */
- Index *pNext; /* The next index associated with the same table */
- Schema *pSchema; /* Schema containing this index */
- u8 *aSortOrder; /* Array of size Index.nColumn. True==DESC, False==ASC */
- char **azColl; /* Array of collation sequence names for index */
- int nColumn; /* Number of columns in the table used by this index */
- int tnum; /* Page containing root of this index in database file */
- u8 onError; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
- u8 autoIndex; /* True if is automatically created (ex: by UNIQUE) */
- u8 bUnordered; /* Use this index for == or IN queries only */
- #ifdef SQLITE_ENABLE_STAT3
- int nSample; /* Number of elements in aSample[] */
- tRowcnt avgEq; /* Average nEq value for key values not in aSample */
- IndexSample *aSample; /* Samples of the left-most key */
- #endif
- };
- /*
- ** Each sample stored in the sqlite_stat3 table is represented in memory
- ** using a structure of this type. See documentation at the top of the
- ** analyze.c source file for additional information.
- */
- struct IndexSample {
- union {
- char *z; /* Value if eType is SQLITE_TEXT or SQLITE_BLOB */
- double r; /* Value if eType is SQLITE_FLOAT */
- i64 i; /* Value if eType is SQLITE_INTEGER */
- } u;
- u8 eType; /* SQLITE_NULL, SQLITE_INTEGER ... etc. */
- int nByte; /* Size in byte of text or blob. */
- tRowcnt nEq; /* Est. number of rows where the key equals this sample */
- tRowcnt nLt; /* Est. number of rows where key is less than this sample */
- tRowcnt nDLt; /* Est. number of distinct keys less than this sample */
- };
- /*
- ** Each token coming out of the lexer is an instance of
- ** this structure. Tokens are also used as part of an expression.
- **
- ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
- ** may contain random values. Do not make any assumptions about Token.dyn
- ** and Token.n when Token.z==0.
- */
- struct Token {
- const char *z; /* Text of the token. Not NULL-terminated! */
- unsigned int n; /* Number of characters in this token */
- };
- /*
- ** An instance of this structure contains information needed to generate
- ** code for a SELECT that contains aggregate functions.
- **
- ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
- ** pointer to this structure. The Expr.iColumn field is the index in
- ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
- ** code for that node.
- **
- ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
- ** original Select structure that describes the SELECT statement. These
- ** fields do not need to be freed when deallocating the AggInfo structure.
- */
- struct AggInfo {
- u8 directMode; /* Direct rendering mode means take data directly
- ** from source tables rather than from accumulators */
- u8 useSortingIdx; /* In direct mode, reference the sorting index rather
- ** than the source table */
- int sortingIdx; /* Cursor number of the sorting index */
- int sortingIdxPTab; /* Cursor number of pseudo-table */
- int nSortingColumn; /* Number of columns in the sorting index */
- ExprList *pGroupBy; /* The group by clause */
- struct AggInfo_col { /* For each column used in source tables */
- Table *pTab; /* Source table */
- int iTable; /* Cursor number of the source table */
- int iColumn; /* Column number within the source table */
- int iSorterColumn; /* Column number in the sorting index */
- int iMem; /* Memory location that acts as accumulator */
- Expr *pExpr; /* The original expression */
- } *aCol;
- int nColumn; /* Number of used entries in aCol[] */
- int nAccumulator; /* Number of columns that show through to the output.
- ** Additional columns are used only as parameters to
- ** aggregate functions */
- struct AggInfo_func { /* For each aggregate function */
- Expr *pExpr; /* Expression encoding the function */
- FuncDef *pFunc; /* The aggregate function implementation */
- int iMem; /* Memory location that acts as accumulator */
- int iDistinct; /* Ephemeral table used to enforce DISTINCT */
- } *aFunc;
- int nFunc; /* Number of entries in aFunc[] */
- };
- /*
- ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
- ** Usually it is 16-bits. But if SQLITE_MAX_VARIABLE_NUMBER is greater
- ** than 32767 we have to make it 32-bit. 16-bit is preferred because
- ** it uses less memory in the Expr object, which is a big memory user
- ** in systems with lots of prepared statements. And few applications
- ** need more than about 10 or 20 variables. But some extreme users want
- ** to have prepared statements with over 32767 variables, and for them
- ** the option is available (at compile-time).
- */
- #if SQLITE_MAX_VARIABLE_NUMBER<=32767
- typedef i16 ynVar;
- #else
- typedef int ynVar;
- #endif
- /*
- ** Each node of an expression in the parse tree is an instance
- ** of this structure.
- **
- ** Expr.op is the opcode. The integer parser token codes are reused
- ** as opcodes here. For example, the parser defines TK_GE to be an integer
- ** code representing the ">=" operator. This same integer code is reused
- ** to represent the greater-than-or-equal-to operator in the expression
- ** tree.
- **
- ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
- ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
- ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
- ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
- ** then Expr.token contains the name of the function.
- **
- ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
- ** binary operator. Either or both may be NULL.
- **
- ** Expr.x.pList is a list of arguments if the expression is an SQL function,
- ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
- ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
- ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
- ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
- ** valid.
- **
- ** An expression of the form ID or ID.ID refers to a column in a table.
- ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
- ** the integer cursor number of a VDBE cursor pointing to that table and
- ** Expr.iColumn is the column number for the specific column. If the
- ** expression is used as a result in an aggregate SELECT, then the
- ** value is also stored in the Expr.iAgg column in the aggregate so that
- ** it can be accessed after all aggregates are computed.
- **
- ** If the expression is an unbound variable marker (a question mark
- ** character '?' in the original SQL) then the Expr.iTable holds the index
- ** number for that variable.
- **
- ** If the expression is a subquery then Expr.iColumn holds an integer
- ** register number containing the result of the subquery. If the
- ** subquery gives a constant result, then iTable is -1. If the subquery
- ** gives a different answer at different times during statement processing
- ** then iTable is the address of a subroutine that computes the subquery.
- **
- ** If the Expr is of type OP_Column, and the table it is selecting from
- ** is a disk table or the "old.*" pseudo-table, then pTab points to the
- ** corresponding table definition.
- **
- ** ALLOCATION NOTES:
- **
- ** Expr objects can use a lot of memory space in database schema. To
- ** help reduce memory requirements, sometimes an Expr object will be
- ** truncated. And to reduce the number of memory allocations, sometimes
- ** two or more Expr objects will be stored in a single memory allocation,
- ** together with Expr.zToken strings.
- **
- ** If the EP_Reduced and EP_TokenOnly flags are set when
- ** an Expr object is truncated. When EP_Reduced is set, then all
- ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
- ** are contained within the same memory allocation. Note, however, that
- ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
- ** allocated, regardless of whether or not EP_Reduced is set.
- */
- struct Expr {
- u8 op; /* Operation performed by this node */
- char affinity; /* The affinity of the column or 0 if not a column */
- u16 flags; /* Various flags. EP_* See below */
- union {
- char *zToken; /* Token value. Zero terminated and dequoted */
- int iValue; /* Non-negative integer value if EP_IntValue */
- } u;
- /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
- ** space is allocated for the fields below this point. An attempt to
- ** access them will result in a segfault or malfunction.
- *********************************************************************/
- Expr *pLeft; /* Left subnode */
- Expr *pRight; /* Right subnode */
- union {
- ExprList *pList; /* Function arguments or in "<expr> IN (<expr-list)" */
- Select *pSelect; /* Used for sub-selects and "<expr> IN (<select>)" */
- } x;
- CollSeq *pColl; /* The collation type of the column or 0 */
- /* If the EP_Reduced flag is set in the Expr.flags mask, then no
- ** space is allocated for the fields below this point. An attempt to
- ** access them will result in a segfault or malfunction.
- *********************************************************************/
- int iTable; /* TK_COLUMN: cursor number of table holding column
- ** TK_REGISTER: register number
- ** TK_TRIGGER: 1 -> new, 0 -> old */
- ynVar iColumn; /* TK_COLUMN: column index. -1 for rowid.
- ** TK_VARIABLE: variable number (always >= 1). */
- i16 iAgg; /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
- i16 iRightJoinTable; /* If EP_FromJoin, the right table of the join */
- u8 flags2; /* Second set of flags. EP2_... */
- u8 op2; /* If a TK_REGISTER, the original value of Expr.op */
- AggInfo *pAggInfo; /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
- Table *pTab; /* Table for TK_COLUMN expressions. */
- #if SQLITE_MAX_EXPR_DEPTH>0
- int nHeight; /* Height of the tree headed by this node */
- #endif
- };
- /*
- ** The following are the meanings of bits in the Expr.flags field.
- */
- #define EP_FromJoin 0x0001 /* Originated in ON or USING clause of a join */
- #define EP_Agg 0x0002 /* Contains one or more aggregate functions */
- #define EP_Resolved 0x0004 /* IDs have been resolved to COLUMNs */
- #define EP_Error 0x0008 /* Expression contains one or more errors */
- #define EP_Distinct 0x0010 /* Aggregate function with DISTINCT keyword */
- #define EP_VarSelect 0x0020 /* pSelect is correlated, not constant */
- #define EP_DblQuoted 0x0040 /* token.z was originally in "..." */
- #define EP_InfixFunc 0x0080 /* True for an infix function: LIKE, GLOB, etc */
- #define EP_ExpCollate 0x0100 /* Collating sequence specified explicitly */
- #define EP_FixedDest 0x0200 /* Result needed in a specific register */
- #define EP_IntValue 0x0400 /* Integer value contained in u.iValue */
- #define EP_xIsSelect 0x0800 /* x.pSelect is valid (otherwise x.pList is) */
- #define EP_Hint 0x1000 /* Optimizer hint. Not required for correctness */
- #define EP_Reduced 0x2000 /* Expr struct is EXPR_REDUCEDSIZE bytes only */
- #define EP_TokenOnly 0x4000 /* Expr struct is EXPR_TOKENONLYSIZE bytes only */
- #define EP_Static 0x8000 /* Held in memory not obtained from malloc() */
- /*
- ** The following are the meanings of bits in the Expr.flags2 field.
- */
- #define EP2_MallocedToken 0x0001 /* Need to sqlite3DbFree() Expr.zToken */
- #define EP2_Irreducible 0x0002 /* Cannot EXPRDUP_REDUCE this Expr */
- /*
- ** The pseudo-routine sqlite3ExprSetIrreducible sets the EP2_Irreducible
- ** flag on an expression structure. This flag is used for VV&A only. The
- ** routine is implemented as a macro that only works when in debugging mode,
- ** so as not to burden production code.
- */
- #ifdef SQLITE_DEBUG
- # define ExprSetIrreducible(X) (X)->flags2 |= EP2_Irreducible
- #else
- # define ExprSetIrreducible(X)
- #endif
- /*
- ** These macros can be used to test, set, or clear bits in the
- ** Expr.flags field.
- */
- #define ExprHasProperty(E,P) (((E)->flags&(P))==(P))
- #define ExprHasAnyProperty(E,P) (((E)->flags&(P))!=0)
- #define ExprSetProperty(E,P) (E)->flags|=(P)
- #define ExprClearProperty(E,P) (E)->flags&=~(P)
- /*
- ** Macros to determine the number of bytes required by a normal Expr
- ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
- ** and an Expr struct with the EP_TokenOnly flag set.
- */
- #define EXPR_FULLSIZE sizeof(Expr) /* Full size */
- #define EXPR_REDUCEDSIZE offsetof(Expr,iTable) /* Common features */
- #define EXPR_TOKENONLYSIZE offsetof(Expr,pLeft) /* Fewer features */
- /*
- ** Flags passed to the sqlite3ExprDup() function. See the header comment
- ** above sqlite3ExprDup() for details.
- */
- #define EXPRDUP_REDUCE 0x0001 /* Used reduced-size Expr nodes */
- /*
- ** A list of expressions. Each expression may optionally have a
- ** name. An expr/name combination can be used in several ways, such
- ** as the list of "expr AS ID" fields following a "SELECT" or in the
- ** list of "ID = expr" items in an UPDATE. A list of expressions can
- ** also be used as the argument to a function, in which case the a.zName
- ** field is not used.
- */
- struct ExprList {
- int nExpr; /* Number of expressions on the list */
- int iECursor; /* VDBE Cursor associated with this ExprList */
- struct ExprList_item { /* For each expression in the list */
- Expr *pExpr; /* The list of expressions */
- char *zName; /* Token associated with this expression */
- char *zSpan; /* Original text of the expression */
- u8 sortOrder; /* 1 for DESC or 0 for ASC */
- u8 done; /* A flag to indicate when processing is finished */
- u16 iOrderByCol; /* For ORDER BY, column number in result set */
- u16 iAlias; /* Index into Parse.aAlias[] for zName */
- } *a; /* Alloc a power of two greater or equal to nExpr */
- };
- /*
- ** An instance of this structure is used by the parser to record both
- ** the parse tree for an expression and the span of input text for an
- ** expression.
- */
- struct ExprSpan {
- Expr *pExpr; /* The expression parse tree */
- const char *zStart; /* First character of input text */
- const char *zEnd; /* One character past the end of input text */
- };
- /*
- ** An instance of this structure can hold a simple list of identifiers,
- ** such as the list "a,b,c" in the following statements:
- **
- ** INSERT INTO t(a,b,c) VALUES ...;
- ** CREATE INDEX idx ON t(a,b,c);
- ** CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
- **
- ** The IdList.a.idx field is used when the IdList represents the list of
- ** column names after a table name in an INSERT statement. In the statement
- **
- ** INSERT INTO t(a,b,c) ...
- **
- ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
- */
- struct IdList {
- struct IdList_item {
- char *zName; /* Name of the identifier */
- int idx; /* Index in some Table.aCol[] of a column named zName */
- } *a;
- int nId; /* Number of identifiers on the list */
- };
- /*
- ** The bitmask datatype defined below is used for various optimizations.
- **
- ** Changing this from a 64-bit to a 32-bit type limits the number of
- ** tables in a join to 32 instead of 64. But it also reduces the size
- ** of the library by 738 bytes on ix86.
- */
- typedef u64 Bitmask;
- /*
- ** The number of bits in a Bitmask. "BMS" means "BitMask Size".
- */
- #define BMS ((int)(sizeof(Bitmask)*8))
- /*
- ** The following structure describes the FROM clause of a SELECT statement.
- ** Each table or subquery in the FROM clause is a separate element of
- ** the SrcList.a[] array.
- **
- ** With the addition of multiple database support, the following structure
- ** can also be used to describe a particular table such as the table that
- ** is modified by an INSERT, DELETE, or UPDATE statement. In standard SQL,
- ** such a table must be a simple name: ID. But in SQLite, the table can
- ** now be identified by a database name, a dot, then the table name: ID.ID.
- **
- ** The jointype starts out showing the join type between the current table
- ** and the next table on the list. The parser builds the list this way.
- ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
- ** jointype expresses the join between the table and the previous table.
- **
- ** In the colUsed field, the high-order bit (bit 63) is set if the table
- ** contains more than 63 columns and the 64-th or later column is used.
- */
- struct SrcList {
- i16 nSrc; /* Number of tables or subqueries in the FROM clause */
- i16 nAlloc; /* Number of entries allocated in a[] below */
- struct SrcList_item {
- char *zDatabase; /* Name of database holding this table */
- char *zName; /* Name of the table */
- char *zAlias; /* The "B" part of a "A AS B" phrase. zName is the "A" */
- Table *pTab; /* An SQL table corresponding to zName */
- Select *pSelect; /* A SELECT statement used in place of a table name */
- int addrFillSub; /* Address of subroutine to manifest a subquery */
- int regReturn; /* Register holding return address of addrFillSub */
- u8 jointype; /* Type of join between this able and the previous */
- u8 notIndexed; /* True if there is a NOT INDEXED clause */
- u8 isCorrelated; /* True if sub-query is correlated */
- #ifndef SQLITE_OMIT_EXPLAIN
- u8 iSelectId; /* If pSelect!=0, the id of the sub-select in EQP */
- #endif
- int iCursor; /* The VDBE cursor number used to access this table */
- Expr *pOn; /* The ON clause of a join */
- IdList *pUsing; /* The USING clause of a join */
- Bitmask colUsed; /* Bit N (1<<N) set if column N of pTab is used */
- char *zIndex; /* Identifier from "INDEXED BY <zIndex>" clause */
- Index *pIndex; /* Index structure corresponding to zIndex, if any */
- } a[1]; /* One entry for each identifier on the list */
- };
- /*
- ** Permitted values of the SrcList.a.jointype field
- */
- #define JT_INNER 0x0001 /* Any kind of inner or cross join */
- #define JT_CROSS 0x0002 /* Explicit use of the CROSS keyword */
- #define JT_NATURAL 0x0004 /* True for a "natural" join */
- #define JT_LEFT 0x0008 /* Left outer join */
- #define JT_RIGHT 0x0010 /* Right outer join */
- #define JT_OUTER 0x0020 /* The "OUTER" keyword is present */
- #define JT_ERROR 0x0040 /* unknown or unsupported join type */
- /*
- ** A WherePlan object holds information that describes a lookup
- ** strategy.
- **
- ** This object is intended to be opaque outside of the where.c module.
- ** It is included here only so that that compiler will know how big it
- ** is. None of the fields in this object should be used outside of
- ** the where.c module.
- **
- ** Within the union, pIdx is only used when wsFlags&WHERE_INDEXED is true.
- ** pTerm is only used when wsFlags&WHERE_MULTI_OR is true. And pVtabIdx
- ** is only used when wsFlags&WHERE_VIRTUALTABLE is true. It is never the
- ** case that more than one of these conditions is true.
- */
- struct WherePlan {
- u32 wsFlags; /* WHERE_* flags that describe the strategy */
- u32 nEq; /* Number of == constraints */
- double nRow; /* Estimated number of rows (for EQP) */
- union {
- Index *pIdx; /* Index when WHERE_INDEXED is true */
- struct WhereTerm *pTerm; /* WHERE clause term for OR-search */
- sqlite3_index_info *pVtabIdx; /* Virtual table index to use */
- } u;
- };
- /*
- ** For each nested loop in a WHERE clause implementation, the WhereInfo
- ** structure contains a single instance of this structure. This structure
- ** is intended to be private the the where.c module and should not be
- ** access or modified by other modules.
- **
- ** The pIdxInfo field is used to help pick the best index on a
- ** virtual table. The pIdxInfo pointer contains indexing
- ** information for the i-th table in the FROM clause before reordering.
- ** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
- ** All other information in the i-th WhereLevel object for the i-th table
- ** after FROM clause ordering.
- */
- struct WhereLevel {
- WherePlan plan; /* query plan for this element of the FROM clause */
- int iLeftJoin; /* Memory cell used to implement LEFT OUTER JOIN */
- int iTabCur; /* The VDBE cursor used to access the table */
- int iIdxCur; /* The VDBE cursor used to access pIdx */
- int addrBrk; /* Jump here to break out of the loop */
- int addrNxt; /* Jump here to start the next IN combination */
- int addrCont; /* Jump here to continue with the next loop cycle */
- int addrFirst; /* First instruction of interior of the loop */
- u8 iFrom; /* Which entry in the FROM clause */
- u8 op, p5; /* Opcode and P5 of the opcode that ends the loop */
- int p1, p2; /* Operands of the opcode used to ends the loop */
- union { /* Information that depends on plan.wsFlags */
- struct {
- int nIn; /* Number of entries in aInLoop[] */
- struct InLoop {
- int iCur; /* The VDBE cursor used by this IN operator */
- int addrInTop; /* Top of the IN loop */
- } *aInLoop; /* Information about each nested IN operator */
- } in; /* Used when plan.wsFlags&WHERE_IN_ABLE */
- } u;
- /* The following field is really not part of the current level. But
- ** we need a place to cache virtual table index information for each
- ** virtual table in the FROM clause and the WhereLevel structure is
- ** a convenient place since there is one WhereLevel for each FROM clause
- ** element.
- */
- sqlite3_index_info *pIdxInfo; /* Index info for n-th source table */
- };
- /*
- ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
- ** and the WhereInfo.wctrlFlags member.
- */
- #define WHERE_ORDERBY_NORMAL 0x0000 /* No-op */
- #define WHERE_ORDERBY_MIN 0x0001 /* ORDER BY processing for min() func */
- #define WHERE_ORDERBY_MAX 0x0002 /* ORDER BY processing for max() func */
- #define WHERE_ONEPASS_DESIRED 0x0004 /* Want to do one-pass UPDATE/DELETE */
- #define WHERE_DUPLICATES_OK 0x0008 /* Ok to return a row more than once */
- #define WHERE_OMIT_OPEN_CLOSE 0x0010 /* Table cursors are already open */
- #define WHERE_FORCE_TABLE 0x0020 /* Do not use an index-only search */
- #define WHERE_ONETABLE_ONLY 0x0040 /* Only code the 1st table in pTabList */
- #define WHERE_AND_ONLY 0x0080 /* Don't use indices for OR terms */
- /*
- ** The WHERE clause processing routine has two halves. The
- ** first part does the start of the WHERE loop and the second
- ** half does the tail of the WHERE loop. An instance of
- ** this structure is returned by the first half and passed
- ** into the second half to give some continuity.
- */
- struct WhereInfo {
- Parse *pParse; /* Parsing and code generating context */
- u16 wctrlFlags; /* Flags originally passed to sqlite3WhereBegin() */
- u8 okOnePass; /* Ok to use one-pass algorithm for UPDATE or DELETE */
- u8 untestedTerms; /* Not all WHERE terms resolved by outer loop */
- u8 eDistinct;
- SrcList *pTabList; /* List of tables in the join */
- int iTop; /* The very beginning of the WHERE loop */
- int iContinue; /* Jump here to continue with next record */
- int iBreak; /* Jump here to break out of the loop */
- int nLevel; /* Number of nested loop */
- struct WhereClause *pWC; /* Decomposition of the WHERE clause */
- double savedNQueryLoop; /* pParse->nQueryLoop outside the WHERE loop */
- double nRowOut; /* Estimated number of output rows */
- WhereLevel a[1]; /* Information about each nest loop in WHERE */
- };
- #define WHERE_DISTINCT_UNIQUE 1
- #define WHERE_DISTINCT_ORDERED 2
- /*
- ** A NameContext defines a context in which to resolve table and column
- ** names. The context consists of a list of tables (the pSrcList) field and
- ** a list of named expression (pEList). The named expression list may
- ** be NULL. The pSrc corresponds to the FROM clause of a SELECT or