xref: /sqlite-3.40.0/src/sqlite.h.in (revision 7fdb522c)
1/*
2** 2001 September 15
3**
4** The author disclaims copyright to this source code.  In place of
5** a legal notice, here is a blessing:
6**
7**    May you do good and not evil.
8**    May you find forgiveness for yourself and forgive others.
9**    May you share freely, never taking more than you give.
10**
11*************************************************************************
12** This header file defines the interface that the SQLite library
13** presents to client programs.  If a C-function, structure, datatype,
14** or constant definition does not appear in this file, then it is
15** not a published API of SQLite, is subject to change without
16** notice, and should not be referenced by programs that use SQLite.
17**
18** Some of the definitions that are in this file are marked as
19** "experimental".  Experimental interfaces are normally new
20** features recently added to SQLite.  We do not anticipate changes
21** to experimental interfaces but reserve to make minor changes if
22** experience from use "in the wild" suggest such changes are prudent.
23**
24** The official C-language API documentation for SQLite is derived
25** from comments in this file.  This file is the authoritative source
26** on how SQLite interfaces are suppose to operate.
27**
28** The name of this file under configuration management is "sqlite.h.in".
29** The makefile makes some minor changes to this file (such as inserting
30** the version number) and changes its name to "sqlite3.h" as
31** part of the build process.
32**
33** @(#) $Id: sqlite.h.in,v 1.382 2008/07/28 19:34:53 drh Exp $
34*/
35#ifndef _SQLITE3_H_
36#define _SQLITE3_H_
37#include <stdarg.h>     /* Needed for the definition of va_list */
38
39/*
40** Make sure we can call this stuff from C++.
41*/
42#ifdef __cplusplus
43extern "C" {
44#endif
45
46
47/*
48** Add the ability to override 'extern'
49*/
50#ifndef SQLITE_EXTERN
51# define SQLITE_EXTERN extern
52#endif
53
54/*
55** Ensure these symbols were not defined by some previous header file.
56*/
57#ifdef SQLITE_VERSION
58# undef SQLITE_VERSION
59#endif
60#ifdef SQLITE_VERSION_NUMBER
61# undef SQLITE_VERSION_NUMBER
62#endif
63
64/*
65** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100>
66**
67** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in
68** the sqlite3.h file specify the version of SQLite with which
69** that header file is associated.
70**
71** The "version" of SQLite is a string of the form "X.Y.Z".
72** The phrase "alpha" or "beta" might be appended after the Z.
73** The X value is major version number always 3 in SQLite3.
74** The X value only changes when backwards compatibility is
75** broken and we intend to never break backwards compatibility.
76** The Y value is the minor version number and only changes when
77** there are major feature enhancements that are forwards compatible
78** but not backwards compatible.
79** The Z value is the release number and is incremented with
80** each release but resets back to 0 whenever Y is incremented.
81**
82** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()].
83**
84** INVARIANTS:
85**
86** {H10011} The SQLITE_VERSION #define in the sqlite3.h header file shall
87**          evaluate to a string literal that is the SQLite version
88**          with which the header file is associated.
89**
90** {H10014} The SQLITE_VERSION_NUMBER #define shall resolve to an integer
91**          with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z
92**          are the major version, minor version, and release number.
93*/
94#define SQLITE_VERSION         "--VERS--"
95#define SQLITE_VERSION_NUMBER  --VERSION-NUMBER--
96
97/*
98** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
99** KEYWORDS: sqlite3_version
100**
101** These features provide the same information as the [SQLITE_VERSION]
102** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated
103** with the library instead of the header file.  Cautious programmers might
104** include a check in their application to verify that
105** sqlite3_libversion_number() always returns the value
106** [SQLITE_VERSION_NUMBER].
107**
108** The sqlite3_libversion() function returns the same information as is
109** in the sqlite3_version[] string constant.  The function is provided
110** for use in DLLs since DLL users usually do not have direct access to string
111** constants within the DLL.
112**
113** INVARIANTS:
114**
115** {H10021} The [sqlite3_libversion_number()] interface shall return
116**          an integer equal to [SQLITE_VERSION_NUMBER].
117**
118** {H10022} The [sqlite3_version] string constant shall contain
119**          the text of the [SQLITE_VERSION] string.
120**
121** {H10023} The [sqlite3_libversion()] function shall return
122**          a pointer to the [sqlite3_version] string constant.
123*/
124SQLITE_EXTERN const char sqlite3_version[];
125const char *sqlite3_libversion(void);
126int sqlite3_libversion_number(void);
127
128/*
129** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100>
130**
131** SQLite can be compiled with or without mutexes.  When
132** the [SQLITE_THREADSAFE] C preprocessor macro is true, mutexes
133** are enabled and SQLite is threadsafe.  When that macro is false,
134** the mutexes are omitted.  Without the mutexes, it is not safe
135** to use SQLite concurrently from more than one thread.
136**
137** Enabling mutexes incurs a measurable performance penalty.
138** So if speed is of utmost importance, it makes sense to disable
139** the mutexes.  But for maximum safety, mutexes should be enabled.
140** The default behavior is for mutexes to be enabled.
141**
142** This interface can be used by a program to make sure that the
143** version of SQLite that it is linking against was compiled with
144** the desired setting of the [SQLITE_THREADSAFE] macro.
145**
146** This interface only reports on the compile-time mutex setting
147** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
148** SQLITE_THREADSAFE=1 then mutexes are enabled by default but
149** can be fully or partially disabled using a call to [sqlite3_config()]
150** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
151** or [SQLITE_CONFIG_MUTEX].  The return value of this function shows
152** only the default compile-time setting, not any run-time changes
153** to that setting.
154**
155** INVARIANTS:
156**
157** {H10101} The [sqlite3_threadsafe()] function shall return nonzero if
158**          SQLite was compiled with the its mutexes enabled by default
159**          or zero if SQLite was compiled such that mutexes are
160**          permanently disabled.
161**
162** {H10102} The value returned by the [sqlite3_threadsafe()] function
163**          shall not change when mutex setting are modified at
164**          runtime using the [sqlite3_config()] interface and
165**          especially the [SQLITE_CONFIG_SINGLETHREAD],
166**          [SQLITE_CONFIG_MULTITHREAD], [SQLITE_CONFIG_SERIALIZED],
167**          and [SQLITE_CONFIG_MUTEX] verbs.
168*/
169int sqlite3_threadsafe(void);
170
171/*
172** CAPI3REF: Database Connection Handle {H12000} <S40200>
173** KEYWORDS: {database connection} {database connections}
174**
175** Each open SQLite database is represented by a pointer to an instance of
176** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
177** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
178** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
179** is its destructor.  There are many other interfaces (such as
180** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
181** [sqlite3_busy_timeout()] to name but three) that are methods on an
182** sqlite3 object.
183*/
184typedef struct sqlite3 sqlite3;
185
186/*
187** CAPI3REF: 64-Bit Integer Types {H10200} <S10110>
188** KEYWORDS: sqlite_int64 sqlite_uint64
189**
190** Because there is no cross-platform way to specify 64-bit integer types
191** SQLite includes typedefs for 64-bit signed and unsigned integers.
192**
193** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
194** The sqlite_int64 and sqlite_uint64 types are supported for backwards
195** compatibility only.
196**
197** INVARIANTS:
198**
199** {H10201} The [sqlite_int64] and [sqlite3_int64] type shall specify
200**          a 64-bit signed integer.
201**
202** {H10202} The [sqlite_uint64] and [sqlite3_uint64] type shall specify
203**          a 64-bit unsigned integer.
204*/
205#ifdef SQLITE_INT64_TYPE
206  typedef SQLITE_INT64_TYPE sqlite_int64;
207  typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
208#elif defined(_MSC_VER) || defined(__BORLANDC__)
209  typedef __int64 sqlite_int64;
210  typedef unsigned __int64 sqlite_uint64;
211#else
212  typedef long long int sqlite_int64;
213  typedef unsigned long long int sqlite_uint64;
214#endif
215typedef sqlite_int64 sqlite3_int64;
216typedef sqlite_uint64 sqlite3_uint64;
217
218/*
219** If compiling for a processor that lacks floating point support,
220** substitute integer for floating-point.
221*/
222#ifdef SQLITE_OMIT_FLOATING_POINT
223# define double sqlite3_int64
224#endif
225
226/*
227** CAPI3REF: Closing A Database Connection {H12010} <S30100><S40200>
228**
229** This routine is the destructor for the [sqlite3] object.
230**
231** Applications should [sqlite3_finalize | finalize] all [prepared statements]
232** and [sqlite3_blob_close | close] all [BLOB handles] associated with
233** the [sqlite3] object prior to attempting to close the object.
234** The [sqlite3_next_stmt()] interface can be used to locate all
235** [prepared statements] associated with a [database connection] if desired.
236** Typical code might look like this:
237**
238** <blockquote><pre>
239** sqlite3_stmt *pStmt;
240** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){
241** &nbsp;   sqlite3_finalize(pStmt);
242** }
243** </pre></blockquote>
244**
245** If [sqlite3_close()] is invoked while a transaction is open,
246** the transaction is automatically rolled back.
247**
248** INVARIANTS:
249**
250** {H12011} A successful call to [sqlite3_close(C)] shall destroy the
251**          [database connection] object C.
252**
253** {H12012} A successful call to [sqlite3_close(C)] shall return SQLITE_OK.
254**
255** {H12013} A successful call to [sqlite3_close(C)] shall release all
256**          memory and system resources associated with [database connection]
257**          C.
258**
259** {H12014} A call to [sqlite3_close(C)] on a [database connection] C that
260**          has one or more open [prepared statements] shall fail with
261**          an [SQLITE_BUSY] error code.
262**
263** {H12015} A call to [sqlite3_close(C)] where C is a NULL pointer shall
264**          return SQLITE_OK.
265**
266** {H12019} When [sqlite3_close(C)] is invoked on a [database connection] C
267**          that has a pending transaction, the transaction shall be
268**          rolled back.
269**
270** ASSUMPTIONS:
271**
272** {A12016} The C parameter to [sqlite3_close(C)] must be either a NULL
273**          pointer or an [sqlite3] object pointer obtained
274**          from [sqlite3_open()], [sqlite3_open16()], or
275**          [sqlite3_open_v2()], and not previously closed.
276*/
277int sqlite3_close(sqlite3 *);
278
279/*
280** The type for a callback function.
281** This is legacy and deprecated.  It is included for historical
282** compatibility and is not documented.
283*/
284typedef int (*sqlite3_callback)(void*,int,char**, char**);
285
286/*
287** CAPI3REF: One-Step Query Execution Interface {H12100} <S10000>
288**
289** The sqlite3_exec() interface is a convenient way of running one or more
290** SQL statements without having to write a lot of C code.  The UTF-8 encoded
291** SQL statements are passed in as the second parameter to sqlite3_exec().
292** The statements are evaluated one by one until either an error or
293** an interrupt is encountered, or until they are all done.  The 3rd parameter
294** is an optional callback that is invoked once for each row of any query
295** results produced by the SQL statements.  The 5th parameter tells where
296** to write any error messages.
297**
298** The error message passed back through the 5th parameter is held
299** in memory obtained from [sqlite3_malloc()].  To avoid a memory leak,
300** the calling application should call [sqlite3_free()] on any error
301** message returned through the 5th parameter when it has finished using
302** the error message.
303**
304** If the SQL statement in the 2nd parameter is NULL or an empty string
305** or a string containing only whitespace and comments, then no SQL
306** statements are evaluated and the database is not changed.
307**
308** The sqlite3_exec() interface is implemented in terms of
309** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
310** The sqlite3_exec() routine does nothing to the database that cannot be done
311** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
312**
313** INVARIANTS:
314**
315** {H12101} A successful invocation of [sqlite3_exec(D,S,C,A,E)]
316**          shall sequentially evaluate all of the UTF-8 encoded,
317**          semicolon-separated SQL statements in the zero-terminated
318**          string S within the context of the [database connection] D.
319**
320** {H12102} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL then
321**          the actions of the interface shall be the same as if the
322**          S parameter were an empty string.
323**
324** {H12104} The return value of [sqlite3_exec()] shall be [SQLITE_OK] if all
325**          SQL statements run successfully and to completion.
326**
327** {H12105} The return value of [sqlite3_exec()] shall be an appropriate
328**          non-zero [error code] if any SQL statement fails.
329**
330** {H12107} If one or more of the SQL statements handed to [sqlite3_exec()]
331**          return results and the 3rd parameter is not NULL, then
332**          the callback function specified by the 3rd parameter shall be
333**          invoked once for each row of result.
334**
335** {H12110} If the callback returns a non-zero value then [sqlite3_exec()]
336**          shall abort the SQL statement it is currently evaluating,
337**          skip all subsequent SQL statements, and return [SQLITE_ABORT].
338**
339** {H12113} The [sqlite3_exec()] routine shall pass its 4th parameter through
340**          as the 1st parameter of the callback.
341**
342** {H12116} The [sqlite3_exec()] routine shall set the 2nd parameter of its
343**          callback to be the number of columns in the current row of
344**          result.
345**
346** {H12119} The [sqlite3_exec()] routine shall set the 3rd parameter of its
347**          callback to be an array of pointers to strings holding the
348**          values for each column in the current result set row as
349**          obtained from [sqlite3_column_text()].
350**
351** {H12122} The [sqlite3_exec()] routine shall set the 4th parameter of its
352**          callback to be an array of pointers to strings holding the
353**          names of result columns as obtained from [sqlite3_column_name()].
354**
355** {H12125} If the 3rd parameter to [sqlite3_exec()] is NULL then
356**          [sqlite3_exec()] shall silently discard query results.
357**
358** {H12131} If an error occurs while parsing or evaluating any of the SQL
359**          statements in the S parameter of [sqlite3_exec(D,S,C,A,E)] and if
360**          the E parameter is not NULL, then [sqlite3_exec()] shall store
361**          in *E an appropriate error message written into memory obtained
362**          from [sqlite3_malloc()].
363**
364** {H12134} The [sqlite3_exec(D,S,C,A,E)] routine shall set the value of
365**          *E to NULL if E is not NULL and there are no errors.
366**
367** {H12137} The [sqlite3_exec(D,S,C,A,E)] function shall set the [error code]
368**          and message accessible via [sqlite3_errcode()],
369**          [sqlite3_errmsg()], and [sqlite3_errmsg16()].
370**
371** {H12138} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL or an
372**          empty string or contains nothing other than whitespace, comments,
373**          and/or semicolons, then results of [sqlite3_errcode()],
374**          [sqlite3_errmsg()], and [sqlite3_errmsg16()]
375**          shall reset to indicate no errors.
376**
377** ASSUMPTIONS:
378**
379** {A12141} The first parameter to [sqlite3_exec()] must be an valid and open
380**          [database connection].
381**
382** {A12142} The database connection must not be closed while
383**          [sqlite3_exec()] is running.
384**
385** {A12143} The calling function should use [sqlite3_free()] to free
386**          the memory that *errmsg is left pointing at once the error
387**          message is no longer needed.
388**
389** {A12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()]
390**          must remain unchanged while [sqlite3_exec()] is running.
391*/
392int sqlite3_exec(
393  sqlite3*,                                  /* An open database */
394  const char *sql,                           /* SQL to be evaluated */
395  int (*callback)(void*,int,char**,char**),  /* Callback function */
396  void *,                                    /* 1st argument to callback */
397  char **errmsg                              /* Error msg written here */
398);
399
400/*
401** CAPI3REF: Result Codes {H10210} <S10700>
402** KEYWORDS: SQLITE_OK {error code} {error codes}
403** KEYWORDS: {result code} {result codes}
404**
405** Many SQLite functions return an integer result code from the set shown
406** here in order to indicates success or failure.
407**
408** New error codes may be added in future versions of SQLite.
409**
410** See also: [SQLITE_IOERR_READ | extended result codes]
411*/
412#define SQLITE_OK           0   /* Successful result */
413/* beginning-of-error-codes */
414#define SQLITE_ERROR        1   /* SQL error or missing database */
415#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
416#define SQLITE_PERM         3   /* Access permission denied */
417#define SQLITE_ABORT        4   /* Callback routine requested an abort */
418#define SQLITE_BUSY         5   /* The database file is locked */
419#define SQLITE_LOCKED       6   /* A table in the database is locked */
420#define SQLITE_NOMEM        7   /* A malloc() failed */
421#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
422#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
423#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
424#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
425#define SQLITE_NOTFOUND    12   /* NOT USED. Table or record not found */
426#define SQLITE_FULL        13   /* Insertion failed because database is full */
427#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
428#define SQLITE_PROTOCOL    15   /* NOT USED. Database lock protocol error */
429#define SQLITE_EMPTY       16   /* Database is empty */
430#define SQLITE_SCHEMA      17   /* The database schema changed */
431#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
432#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
433#define SQLITE_MISMATCH    20   /* Data type mismatch */
434#define SQLITE_MISUSE      21   /* Library used incorrectly */
435#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
436#define SQLITE_AUTH        23   /* Authorization denied */
437#define SQLITE_FORMAT      24   /* Auxiliary database format error */
438#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
439#define SQLITE_NOTADB      26   /* File opened that is not a database file */
440#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
441#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
442/* end-of-error-codes */
443
444/*
445** CAPI3REF: Extended Result Codes {H10220} <S10700>
446** KEYWORDS: {extended error code} {extended error codes}
447** KEYWORDS: {extended result code} {extended result codes}
448**
449** In its default configuration, SQLite API routines return one of 26 integer
450** [SQLITE_OK | result codes].  However, experience has shown that many of
451** these result codes are too coarse-grained.  They do not provide as
452** much information about problems as programmers might like.  In an effort to
453** address this, newer versions of SQLite (version 3.3.8 and later) include
454** support for additional result codes that provide more detailed information
455** about errors. The extended result codes are enabled or disabled
456** on a per database connection basis using the
457** [sqlite3_extended_result_codes()] API.
458**
459** Some of the available extended result codes are listed here.
460** One may expect the number of extended result codes will be expand
461** over time.  Software that uses extended result codes should expect
462** to see new result codes in future releases of SQLite.
463**
464** The SQLITE_OK result code will never be extended.  It will always
465** be exactly zero.
466**
467** INVARIANTS:
468**
469** {H10223} The symbolic name for an extended result code shall contains
470**          a related primary result code as a prefix.
471**
472** {H10224} Primary result code names shall contain a single "_" character.
473**
474** {H10225} Extended result code names shall contain two or more "_" characters.
475**
476** {H10226} The numeric value of an extended result code shall contain the
477**          numeric value of its corresponding primary result code in
478**          its least significant 8 bits.
479*/
480#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
481#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
482#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
483#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
484#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
485#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
486#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
487#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
488#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
489#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
490#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
491#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
492#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
493#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
494
495/*
496** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700>
497**
498** These bit values are intended for use in the
499** 3rd parameter to the [sqlite3_open_v2()] interface and
500** in the 4th parameter to the xOpen method of the
501** [sqlite3_vfs] object.
502*/
503#define SQLITE_OPEN_READONLY         0x00000001
504#define SQLITE_OPEN_READWRITE        0x00000002
505#define SQLITE_OPEN_CREATE           0x00000004
506#define SQLITE_OPEN_DELETEONCLOSE    0x00000008
507#define SQLITE_OPEN_EXCLUSIVE        0x00000010
508#define SQLITE_OPEN_MAIN_DB          0x00000100
509#define SQLITE_OPEN_TEMP_DB          0x00000200
510#define SQLITE_OPEN_TRANSIENT_DB     0x00000400
511#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800
512#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000
513#define SQLITE_OPEN_SUBJOURNAL       0x00002000
514#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000
515#define SQLITE_OPEN_NOMUTEX          0x00008000
516
517/*
518** CAPI3REF: Device Characteristics {H10240} <H11120>
519**
520** The xDeviceCapabilities method of the [sqlite3_io_methods]
521** object returns an integer which is a vector of the these
522** bit values expressing I/O characteristics of the mass storage
523** device that holds the file that the [sqlite3_io_methods]
524** refers to.
525**
526** The SQLITE_IOCAP_ATOMIC property means that all writes of
527** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
528** mean that writes of blocks that are nnn bytes in size and
529** are aligned to an address which is an integer multiple of
530** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
531** that when data is appended to a file, the data is appended
532** first then the size of the file is extended, never the other
533** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
534** information is written to disk in the same order as calls
535** to xWrite().
536*/
537#define SQLITE_IOCAP_ATOMIC          0x00000001
538#define SQLITE_IOCAP_ATOMIC512       0x00000002
539#define SQLITE_IOCAP_ATOMIC1K        0x00000004
540#define SQLITE_IOCAP_ATOMIC2K        0x00000008
541#define SQLITE_IOCAP_ATOMIC4K        0x00000010
542#define SQLITE_IOCAP_ATOMIC8K        0x00000020
543#define SQLITE_IOCAP_ATOMIC16K       0x00000040
544#define SQLITE_IOCAP_ATOMIC32K       0x00000080
545#define SQLITE_IOCAP_ATOMIC64K       0x00000100
546#define SQLITE_IOCAP_SAFE_APPEND     0x00000200
547#define SQLITE_IOCAP_SEQUENTIAL      0x00000400
548
549/*
550** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310>
551**
552** SQLite uses one of these integer values as the second
553** argument to calls it makes to the xLock() and xUnlock() methods
554** of an [sqlite3_io_methods] object.
555*/
556#define SQLITE_LOCK_NONE          0
557#define SQLITE_LOCK_SHARED        1
558#define SQLITE_LOCK_RESERVED      2
559#define SQLITE_LOCK_PENDING       3
560#define SQLITE_LOCK_EXCLUSIVE     4
561
562/*
563** CAPI3REF: Synchronization Type Flags {H10260} <H11120>
564**
565** When SQLite invokes the xSync() method of an
566** [sqlite3_io_methods] object it uses a combination of
567** these integer values as the second argument.
568**
569** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
570** sync operation only needs to flush data to mass storage.  Inode
571** information need not be flushed. The SQLITE_SYNC_NORMAL flag means
572** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means
573** to use Mac OS-X style fullsync instead of fsync().
574*/
575#define SQLITE_SYNC_NORMAL        0x00002
576#define SQLITE_SYNC_FULL          0x00003
577#define SQLITE_SYNC_DATAONLY      0x00010
578
579/*
580** CAPI3REF: OS Interface Open File Handle {H11110} <S20110>
581**
582** An [sqlite3_file] object represents an open file in the OS
583** interface layer.  Individual OS interface implementations will
584** want to subclass this object by appending additional fields
585** for their own use.  The pMethods entry is a pointer to an
586** [sqlite3_io_methods] object that defines methods for performing
587** I/O operations on the open file.
588*/
589typedef struct sqlite3_file sqlite3_file;
590struct sqlite3_file {
591  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
592};
593
594/*
595** CAPI3REF: OS Interface File Virtual Methods Object {H11120} <S20110>
596**
597** Every file opened by the [sqlite3_vfs] xOpen method populates an
598** [sqlite3_file] object (or, more commonly, a subclass of the
599** [sqlite3_file] object) with a pointer to an instance of this object.
600** This object defines the methods used to perform various operations
601** against the open file represented by the [sqlite3_file] object.
602**
603** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
604** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
605** The second choice is a Mac OS-X style fullsync.  The [SQLITE_SYNC_DATAONLY]
606** flag may be ORed in to indicate that only the data of the file
607** and not its inode needs to be synced.
608**
609** The integer values to xLock() and xUnlock() are one of
610** <ul>
611** <li> [SQLITE_LOCK_NONE],
612** <li> [SQLITE_LOCK_SHARED],
613** <li> [SQLITE_LOCK_RESERVED],
614** <li> [SQLITE_LOCK_PENDING], or
615** <li> [SQLITE_LOCK_EXCLUSIVE].
616** </ul>
617** xLock() increases the lock. xUnlock() decreases the lock.
618** The xCheckReservedLock() method checks whether any database connection,
619** either in this process or in some other process, is holding a RESERVED,
620** PENDING, or EXCLUSIVE lock on the file.  It returns true
621** if such a lock exists and false otherwise.
622**
623** The xFileControl() method is a generic interface that allows custom
624** VFS implementations to directly control an open file using the
625** [sqlite3_file_control()] interface.  The second "op" argument is an
626** integer opcode.  The third argument is a generic pointer intended to
627** point to a structure that may contain arguments or space in which to
628** write return values.  Potential uses for xFileControl() might be
629** functions to enable blocking locks with timeouts, to change the
630** locking strategy (for example to use dot-file locks), to inquire
631** about the status of a lock, or to break stale locks.  The SQLite
632** core reserves all opcodes less than 100 for its own use.
633** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
634** Applications that define a custom xFileControl method should use opcodes
635** greater than 100 to avoid conflicts.
636**
637** The xSectorSize() method returns the sector size of the
638** device that underlies the file.  The sector size is the
639** minimum write that can be performed without disturbing
640** other bytes in the file.  The xDeviceCharacteristics()
641** method returns a bit vector describing behaviors of the
642** underlying device:
643**
644** <ul>
645** <li> [SQLITE_IOCAP_ATOMIC]
646** <li> [SQLITE_IOCAP_ATOMIC512]
647** <li> [SQLITE_IOCAP_ATOMIC1K]
648** <li> [SQLITE_IOCAP_ATOMIC2K]
649** <li> [SQLITE_IOCAP_ATOMIC4K]
650** <li> [SQLITE_IOCAP_ATOMIC8K]
651** <li> [SQLITE_IOCAP_ATOMIC16K]
652** <li> [SQLITE_IOCAP_ATOMIC32K]
653** <li> [SQLITE_IOCAP_ATOMIC64K]
654** <li> [SQLITE_IOCAP_SAFE_APPEND]
655** <li> [SQLITE_IOCAP_SEQUENTIAL]
656** </ul>
657**
658** The SQLITE_IOCAP_ATOMIC property means that all writes of
659** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
660** mean that writes of blocks that are nnn bytes in size and
661** are aligned to an address which is an integer multiple of
662** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
663** that when data is appended to a file, the data is appended
664** first then the size of the file is extended, never the other
665** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
666** information is written to disk in the same order as calls
667** to xWrite().
668*/
669typedef struct sqlite3_io_methods sqlite3_io_methods;
670struct sqlite3_io_methods {
671  int iVersion;
672  int (*xClose)(sqlite3_file*);
673  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
674  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
675  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
676  int (*xSync)(sqlite3_file*, int flags);
677  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
678  int (*xLock)(sqlite3_file*, int);
679  int (*xUnlock)(sqlite3_file*, int);
680  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
681  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
682  int (*xSectorSize)(sqlite3_file*);
683  int (*xDeviceCharacteristics)(sqlite3_file*);
684  /* Additional methods may be added in future releases */
685};
686
687/*
688** CAPI3REF: Standard File Control Opcodes {H11310} <S30800>
689**
690** These integer constants are opcodes for the xFileControl method
691** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
692** interface.
693**
694** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
695** opcode causes the xFileControl method to write the current state of
696** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
697** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
698** into an integer that the pArg argument points to. This capability
699** is used during testing and only needs to be supported when SQLITE_TEST
700** is defined.
701*/
702#define SQLITE_FCNTL_LOCKSTATE        1
703
704/*
705** CAPI3REF: Mutex Handle {H17110} <S20130>
706**
707** The mutex module within SQLite defines [sqlite3_mutex] to be an
708** abstract type for a mutex object.  The SQLite core never looks
709** at the internal representation of an [sqlite3_mutex].  It only
710** deals with pointers to the [sqlite3_mutex] object.
711**
712** Mutexes are created using [sqlite3_mutex_alloc()].
713*/
714typedef struct sqlite3_mutex sqlite3_mutex;
715
716/*
717** CAPI3REF: OS Interface Object {H11140} <S20100>
718**
719** An instance of the sqlite3_vfs object defines the interface between
720** the SQLite core and the underlying operating system.  The "vfs"
721** in the name of the object stands for "virtual file system".
722**
723** The value of the iVersion field is initially 1 but may be larger in
724** future versions of SQLite.  Additional fields may be appended to this
725** object when the iVersion value is increased.  Note that the structure
726** of the sqlite3_vfs object changes in the transaction between
727** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
728** modified.
729**
730** The szOsFile field is the size of the subclassed [sqlite3_file]
731** structure used by this VFS.  mxPathname is the maximum length of
732** a pathname in this VFS.
733**
734** Registered sqlite3_vfs objects are kept on a linked list formed by
735** the pNext pointer.  The [sqlite3_vfs_register()]
736** and [sqlite3_vfs_unregister()] interfaces manage this list
737** in a thread-safe way.  The [sqlite3_vfs_find()] interface
738** searches the list.  Neither the application code nor the VFS
739** implementation should use the pNext pointer.
740**
741** The pNext field is the only field in the sqlite3_vfs
742** structure that SQLite will ever modify.  SQLite will only access
743** or modify this field while holding a particular static mutex.
744** The application should never modify anything within the sqlite3_vfs
745** object once the object has been registered.
746**
747** The zName field holds the name of the VFS module.  The name must
748** be unique across all VFS modules.
749**
750** {H11141} SQLite will guarantee that the zFilename parameter to xOpen
751** is either a NULL pointer or string obtained
752** from xFullPathname().  SQLite further guarantees that
753** the string will be valid and unchanged until xClose() is
754** called. {END}  Because of the previous sentense,
755** the [sqlite3_file] can safely store a pointer to the
756** filename if it needs to remember the filename for some reason.
757** If the zFilename parameter is xOpen is a NULL pointer then xOpen
758** must invite its own temporary name for the file.  Whenever the
759** xFilename parameter is NULL it will also be the case that the
760** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
761**
762** {H11142} The flags argument to xOpen() includes all bits set in
763** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
764** or [sqlite3_open16()] is used, then flags includes at least
765** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. {END}
766** If xOpen() opens a file read-only then it sets *pOutFlags to
767** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
768**
769** {H11143} SQLite will also add one of the following flags to the xOpen()
770** call, depending on the object being opened:
771**
772** <ul>
773** <li>  [SQLITE_OPEN_MAIN_DB]
774** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
775** <li>  [SQLITE_OPEN_TEMP_DB]
776** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
777** <li>  [SQLITE_OPEN_TRANSIENT_DB]
778** <li>  [SQLITE_OPEN_SUBJOURNAL]
779** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
780** </ul> {END}
781**
782** The file I/O implementation can use the object type flags to
783** change the way it deals with files.  For example, an application
784** that does not care about crash recovery or rollback might make
785** the open of a journal file a no-op.  Writes to this journal would
786** also be no-ops, and any attempt to read the journal would return
787** SQLITE_IOERR.  Or the implementation might recognize that a database
788** file will be doing page-aligned sector reads and writes in a random
789** order and set up its I/O subsystem accordingly.
790**
791** SQLite might also add one of the following flags to the xOpen method:
792**
793** <ul>
794** <li> [SQLITE_OPEN_DELETEONCLOSE]
795** <li> [SQLITE_OPEN_EXCLUSIVE]
796** </ul>
797**
798** {H11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
799** deleted when it is closed.  {H11146} The [SQLITE_OPEN_DELETEONCLOSE]
800** will be set for TEMP  databases, journals and for subjournals.
801**
802** {H11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened
803** for exclusive access.  This flag is set for all files except
804** for the main database file.
805**
806** {H11148} At least szOsFile bytes of memory are allocated by SQLite
807** to hold the  [sqlite3_file] structure passed as the third
808** argument to xOpen. {END}  The xOpen method does not have to
809** allocate the structure; it should just fill it in.
810**
811** {H11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
812** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
813** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
814** to test whether a file is at least readable. {END}  The file can be a
815** directory.
816**
817** {H11150} SQLite will always allocate at least mxPathname+1 bytes for the
818** output buffer xFullPathname. {H11151} The exact size of the output buffer
819** is also passed as a parameter to both  methods. {END}  If the output buffer
820** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
821** handled as a fatal error by SQLite, vfs implementations should endeavor
822** to prevent this by setting mxPathname to a sufficiently large value.
823**
824** The xRandomness(), xSleep(), and xCurrentTime() interfaces
825** are not strictly a part of the filesystem, but they are
826** included in the VFS structure for completeness.
827** The xRandomness() function attempts to return nBytes bytes
828** of good-quality randomness into zOut.  The return value is
829** the actual number of bytes of randomness obtained.
830** The xSleep() method causes the calling thread to sleep for at
831** least the number of microseconds given.  The xCurrentTime()
832** method returns a Julian Day Number for the current date and time.
833*/
834typedef struct sqlite3_vfs sqlite3_vfs;
835struct sqlite3_vfs {
836  int iVersion;            /* Structure version number */
837  int szOsFile;            /* Size of subclassed sqlite3_file */
838  int mxPathname;          /* Maximum file pathname length */
839  sqlite3_vfs *pNext;      /* Next registered VFS */
840  const char *zName;       /* Name of this virtual file system */
841  void *pAppData;          /* Pointer to application-specific data */
842  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
843               int flags, int *pOutFlags);
844  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
845  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
846  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
847  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
848  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
849  void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
850  void (*xDlClose)(sqlite3_vfs*, void*);
851  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
852  int (*xSleep)(sqlite3_vfs*, int microseconds);
853  int (*xCurrentTime)(sqlite3_vfs*, double*);
854  int (*xGetLastError)(sqlite3_vfs*, int, char *);
855  /* New fields may be appended in figure versions.  The iVersion
856  ** value will increment whenever this happens. */
857};
858
859/*
860** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140>
861**
862** {H11191} These integer constants can be used as the third parameter to
863** the xAccess method of an [sqlite3_vfs] object. {END}  They determine
864** what kind of permissions the xAccess method is looking for.
865** {H11192} With SQLITE_ACCESS_EXISTS, the xAccess method
866** simply checks whether the file exists.
867** {H11193} With SQLITE_ACCESS_READWRITE, the xAccess method
868** checks whether the file is both readable and writable.
869** {H11194} With SQLITE_ACCESS_READ, the xAccess method
870** checks whether the file is readable.
871*/
872#define SQLITE_ACCESS_EXISTS    0
873#define SQLITE_ACCESS_READWRITE 1
874#define SQLITE_ACCESS_READ      2
875
876/*
877** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100>
878**
879** The sqlite3_initialize() routine initializes the
880** SQLite library.  The sqlite3_shutdown() routine
881** deallocates any resources that were allocated by sqlite3_initialize().
882**
883** A call to sqlite3_initialize() is an "effective" call if it is
884** the first time sqlite3_initialize() is invoked during the lifetime of
885** the process, or if it is the first time sqlite3_initialize() is invoked
886** following a call to sqlite3_shutdown().  Only an effective call
887** of sqlite3_initialize() does any initialization.  All other calls
888** are harmless no-ops.
889**
890** Among other things, sqlite3_initialize() shall invoke
891** sqlite3_os_init().  Similarly, sqlite3_shutdown()
892** shall invoke sqlite3_os_end().
893**
894** The sqlite3_initialize() routine returns SQLITE_OK on success.
895** If for some reason, sqlite3_initialize() is unable to initialize
896** the library (perhaps it is unable to allocate a needed resource such
897** as a mutex) it returns an [error code] other than SQLITE_OK.
898**
899** The sqlite3_initialize() routine is called internally by many other
900** SQLite interfaces so that an application usually does not need to
901** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
902** calls sqlite3_initialize() so the SQLite library will be automatically
903** initialized when [sqlite3_open()] is called if it has not be initialized
904** already.  However, if SQLite is compiled with the SQLITE_OMIT_AUTOINIT
905** compile-time option, then the automatic calls to sqlite3_initialize()
906** are omitted and the application must call sqlite3_initialize() directly
907** prior to using any other SQLite interface.  For maximum portability,
908** it is recommended that applications always invoke sqlite3_initialize()
909** directly prior to using any other SQLite interface.  Future releases
910** of SQLite may require this.  In other words, the behavior exhibited
911** when SQLite is compiled with SQLITE_OMIT_AUTOINIT might become the
912** default behavior in some future release of SQLite.
913**
914** The sqlite3_os_init() routine does operating-system specific
915** initialization of the SQLite library.  The sqlite3_os_end()
916** routine undoes the effect of sqlite3_os_init().  Typical tasks
917** performed by these routines include allocation or deallocation
918** of static resources, initialization of global variables,
919** setting up a default [sqlite3_vfs] module, or setting up
920** a default configuration using [sqlite3_config()].
921**
922** The application should never invoke either sqlite3_os_init()
923** or sqlite3_os_end() directly.  The application should only invoke
924** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
925** interface is called automatically by sqlite3_initialize() and
926** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
927** implementations for sqlite3_os_init() and sqlite3_os_end()
928** are built into SQLite when it is compiled for unix, windows, or os/2.
929** When built for other platforms (using the SQLITE_OS_OTHER=1 compile-time
930** option) the application must supply a suitable implementation for
931** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
932** implementation of sqlite3_os_init() or sqlite3_os_end()
933** must return SQLITE_OK on success and some other [error code] upon
934** failure.
935*/
936int sqlite3_initialize(void);
937int sqlite3_shutdown(void);
938int sqlite3_os_init(void);
939int sqlite3_os_end(void);
940
941/*
942** CAPI3REF: Configuring The SQLite Library {H10145} <S20000><S30200>
943**
944** The sqlite3_config() interface is used to make global configuration
945** changes to SQLite in order to tune SQLite to the specific needs of
946** the application.  The default configuration is recommended for most
947** applications and so this routine is usually not necessary.  It is
948** provided to support rare applications with unusual needs.
949**
950** The sqlite3_config() interface is not threadsafe.  The application
951** must insure that no other SQLite interfaces are invoked by other
952** threads while sqlite3_config() is running.  Furthermore, sqlite3_config()
953** may only be invoked prior to library initialization using
954** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
955** Note, however, that sqlite3_config() can be called as part of the
956** implementation of an application-defined [sqlite3_os_init()].
957**
958** The first argument to sqlite3_config() is an integer
959** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
960** what property of SQLite is to be configured.  Subsequent arguments
961** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
962** in the first argument.
963**
964** When a configuration option is set, sqlite3_config() returns SQLITE_OK.
965** If the option is unknown or SQLite is unable to set the option
966** then this routine returns a non-zero [error code].
967**
968** The sqlite3_config() interface is considered experimental in that
969** new configuration options may be added in future releases and existing
970** configuration options may be discontinued or modified.
971*/
972int sqlite3_config(int, ...);
973
974/*
975** CAPI3REF: Configure database connections  {H10180} <S20000>
976**
977** The sqlite3_db_config() interface is used to make configuration
978** changes to a [database connection].
979*/
980int sqlite3_db_config(sqlite3*, int, ...);
981
982/*
983** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
984**
985** An instance of this object defines the interface between SQLite
986** and low-level memory allocation routines.
987**
988** This object is used in only one place in the SQLite interface.
989** A pointer to an instance of this object is the argument to
990** [sqlite3_config()] when the configuration option is
991** [SQLITE_CONFIG_MALLOC].  By creating an instance of this object
992** and passing it to [sqlite3_config()] during configuration, an
993** application can specify an alternative memory allocation subsystem
994** for SQLite to use for all of its dynamic memory needs.
995**
996** Note that SQLite comes with a built-in memory allocator that is
997** perfectly adequate for the overwhelming majority of applications
998** and that this object is only useful to a tiny minority of applications
999** with specialized memory allocation requirements.  This object is
1000** also used during testing of SQLite in order to specify an alternative
1001** memory allocator that simulates memory out-of-memory conditions in
1002** order to verify that SQLite recovers gracefully from such
1003** conditions.
1004**
1005** The xMalloc, xFree, and xRealloc methods must work like the
1006** malloc(), free(), and realloc() functions from the standard library.
1007**
1008** xSize should return the allocated size of a memory allocation
1009** previously obtained from xMalloc or xRealloc.  The allocated size
1010** is always at least as big as the requested size but may be larger.
1011**
1012** The xRoundup method returns what would be the allocated size of
1013** a memory allocation given a particular requested size.  Most memory
1014** allocators round up memory allocations at least to the next multiple
1015** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1016**
1017** The xInit method initializes the memory allocator.  (For example,
1018** it might allocate any require mutexes or initialize internal data
1019** structures.  The xShutdown method is invoked (indirectly) by
1020** [sqlite3_shutdown()] and should deallocate any resources acquired
1021** by xInit.  The pAppData pointer is used as the only parameter to
1022** xInit and xShutdown.
1023*/
1024typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1025struct sqlite3_mem_methods {
1026  void *(*xMalloc)(int);         /* Memory allocation function */
1027  void (*xFree)(void*);          /* Free a prior allocation */
1028  void *(*xRealloc)(void*,int);  /* Resize an allocation */
1029  int (*xSize)(void*);           /* Return the size of an allocation */
1030  int (*xRoundup)(int);          /* Round up request size to allocation size */
1031  int (*xInit)(void*);           /* Initialize the memory allocator */
1032  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
1033  void *pAppData;                /* Argument to xInit() and xShutdown() */
1034};
1035
1036/*
1037** CAPI3REF: Configuration Options {H10160} <S20000>
1038**
1039** These constants are the available integer configuration options that
1040** can be passed as the first argument to the [sqlite3_config()] interface.
1041**
1042** New configuration options may be added in future releases of SQLite.
1043** Existing configuration options might be discontinued.  Applications
1044** should check the return code from [sqlite3_config()] to make sure that
1045** the call worked.  The [sqlite3_config()] interface will return a
1046** non-zero [error code] if a discontinued or unsupported configuration option
1047** is invoked.
1048**
1049** <dl>
1050** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1051** <dd>There are no arguments to this option.  This option disables
1052** all mutexing and puts SQLite into a mode where it can only be used
1053** by a single thread.</dd>
1054**
1055** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1056** <dd>There are no arguments to this option.  This option disables
1057** mutexing on [database connection] and [prepared statement] objects.
1058** The application is responsible for serializing access to
1059** [database connections] and [prepared statements].  But other mutexes
1060** are enabled so that SQLite will be safe to use in a multi-threaded
1061** environment.</dd>
1062**
1063** <dt>SQLITE_CONFIG_SERIALIZED</dt>
1064** <dd>There are no arguments to this option.  This option enables
1065** all mutexes including the recursive
1066** mutexes on [database connection] and [prepared statement] objects.
1067** In this mode (which is the default when SQLite is compiled with
1068** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1069** to [database connections] and [prepared statements] so that the
1070** application is free to use the same [database connection] or the
1071** same [prepared statement] in different threads at the same time.
1072**
1073** <p>This configuration option merely sets the default mutex
1074** behavior to serialize access to [database connections].  Individual
1075** [database connections] can override this setting
1076** using the [SQLITE_OPEN_NOMUTEX] flag to [sqlite3_open_v2()].</p></dd>
1077**
1078** <dt>SQLITE_CONFIG_MALLOC</dt>
1079** <dd>This option takes a single argument which is a pointer to an
1080** instance of the [sqlite3_mem_methods] structure.  The argument specifies
1081** alternative low-level memory allocation routines to be used in place of
1082** the memory allocation routines built into SQLite.</dd>
1083**
1084** <dt>SQLITE_CONFIG_GETMALLOC</dt>
1085** <dd>This option takes a single argument which is a pointer to an
1086** instance of the [sqlite3_mem_methods] structure.  The [sqlite3_mem_methods]
1087** structure is filled with the currently defined memory allocation routines.
1088** This option can be used to overload the default memory allocation
1089** routines with a wrapper that simulations memory allocation failure or
1090** tracks memory usage, for example.</dd>
1091**
1092** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1093** <dd>This option takes single argument of type int, interpreted as a
1094** boolean, which enables or disables the collection of memory allocation
1095** statistics. When disabled, the following SQLite interfaces become
1096** non-operational:
1097**   <ul>
1098**   <li> [sqlite3_memory_used()]
1099**   <li> [sqlite3_memory_highwater()]
1100**   <li> [sqlite3_soft_heap_limit()]
1101**   <li> sqlite3_memory_status()
1102**   </ul>
1103** </dd>
1104**
1105** <dt>SQLITE_CONFIG_SCRATCH</dt>
1106** <dd>This option specifies a static memory buffer that SQLite can use for
1107** scratch memory.  There are three arguments:  A pointer to the memory, the
1108** size of each scratch buffer (sz), and the number of buffers (N).  The sz
1109** argument must be a multiple of 16. The first
1110** argument should point to an allocation of at least (sz+4)*N bytes of memory.
1111** SQLite will use no more than one scratch buffer at once per thread, so
1112** N should be set to the expected maximum number of threads.  The sz
1113** parameter should be 6 times the size of the largest database page size.
1114** Scratch buffers are used as part of the btree balance operation.  If
1115** The btree balancer needs additional memory beyond what is provided by
1116** scratch buffers or if no scratch buffer space is specified, then SQLite
1117** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd>
1118**
1119** <dt>SQLITE_CONFIG_PAGECACHE</dt>
1120** <dd>This option specifies a static memory buffer that SQLite can use for
1121** the database page cache.  There are three arguments: A pointer to the
1122** memory, the size of each page buffer (sz), and the number of pages (N).
1123** The sz argument must be a power of two between 512 and 32768.  The first
1124** argument should point to an allocation of at least (sz+4)*N bytes of memory.
1125** SQLite will use the memory provided by the first argument to satisfy its
1126** memory needs for the first N pages that it adds to cache.  If additional
1127** page cache memory is needed beyond what is provided by this option, then
1128** SQLite goes to [sqlite3_malloc()] for the additional storage space.</dd>
1129**
1130** <dt>SQLITE_CONFIG_HEAP</dt>
1131** <dd>This option specifies a static memory buffer that SQLite will use
1132** for all of its dynamic memory allocation needs beyond those provided
1133** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
1134** There are three arguments: A pointer to the memory, the number of
1135** bytes in the memory buffer, and the minimum allocation size.  If
1136** the first pointer (the memory pointer) is NULL, then SQLite reverts
1137** to using its default memory allocator (the system malloc() implementation),
1138** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  If the
1139** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
1140** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
1141** allocator is engaged to handle all of SQLites memory allocation needs.</dd>
1142**
1143** <dt>SQLITE_CONFIG_MUTEX</dt>
1144** <dd>This option takes a single argument which is a pointer to an
1145** instance of the [sqlite3_mutex_methods] structure.  The argument specifies
1146** alternative low-level mutex routines to be used in place
1147** the mutex routines built into SQLite.</dd>
1148**
1149** <dt>SQLITE_CONFIG_GETMUTEX</dt>
1150** <dd>This option takes a single argument which is a pointer to an
1151** instance of the [sqlite3_mutex_methods] structure.  The
1152** [sqlite3_mutex_methods]
1153** structure is filled with the currently defined mutex routines.
1154** This option can be used to overload the default mutex allocation
1155** routines with a wrapper used to track mutex usage for performance
1156** profiling or testing, for example.</dd>
1157**
1158** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1159** <dd>This option takes two arguments that determine the default
1160** memory allcation lookaside optimization.  The first argument is the
1161** size of each lookaside buffer slot and the second is the number of
1162** slots allocated to each database connection.</dd>
1163**
1164** </dl>
1165*/
1166#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
1167#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
1168#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
1169#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
1170#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
1171#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
1172#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
1173#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
1174#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
1175#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
1176#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
1177#define SQLITE_CONFIG_CHUNKALLOC   12  /* int threshold */
1178#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
1179
1180
1181/*
1182** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
1183**
1184** The sqlite3_extended_result_codes() routine enables or disables the
1185** [extended result codes] feature of SQLite. The extended result
1186** codes are disabled by default for historical compatibility considerations.
1187**
1188** INVARIANTS:
1189**
1190** {H12201} Each new [database connection] shall have the
1191**          [extended result codes] feature disabled by default.
1192**
1193** {H12202} The [sqlite3_extended_result_codes(D,F)] interface shall enable
1194**          [extended result codes] for the  [database connection] D
1195**          if the F parameter is true, or disable them if F is false.
1196*/
1197int sqlite3_extended_result_codes(sqlite3*, int onoff);
1198
1199/*
1200** CAPI3REF: Last Insert Rowid {H12220} <S10700>
1201**
1202** Each entry in an SQLite table has a unique 64-bit signed
1203** integer key called the "rowid". The rowid is always available
1204** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
1205** names are not also used by explicitly declared columns. If
1206** the table has a column of type INTEGER PRIMARY KEY then that column
1207** is another alias for the rowid.
1208**
1209** This routine returns the rowid of the most recent
1210** successful INSERT into the database from the [database connection]
1211** in the first argument.  If no successful INSERTs
1212** have ever occurred on that database connection, zero is returned.
1213**
1214** If an INSERT occurs within a trigger, then the rowid of the inserted
1215** row is returned by this routine as long as the trigger is running.
1216** But once the trigger terminates, the value returned by this routine
1217** reverts to the last value inserted before the trigger fired.
1218**
1219** An INSERT that fails due to a constraint violation is not a
1220** successful INSERT and does not change the value returned by this
1221** routine.  Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
1222** and INSERT OR ABORT make no changes to the return value of this
1223** routine when their insertion fails.  When INSERT OR REPLACE
1224** encounters a constraint violation, it does not fail.  The
1225** INSERT continues to completion after deleting rows that caused
1226** the constraint problem so INSERT OR REPLACE will always change
1227** the return value of this interface.
1228**
1229** For the purposes of this routine, an INSERT is considered to
1230** be successful even if it is subsequently rolled back.
1231**
1232** INVARIANTS:
1233**
1234** {H12221} The [sqlite3_last_insert_rowid()] function returns the rowid
1235**          of the most recent successful INSERT performed on the same
1236**          [database connection] and within the same or higher level
1237**          trigger context, or zero if there have been no qualifying inserts.
1238**
1239** {H12223} The [sqlite3_last_insert_rowid()] function returns the
1240**          same value when called from the same trigger context
1241**          immediately before and after a ROLLBACK.
1242**
1243** ASSUMPTIONS:
1244**
1245** {A12232} If a separate thread performs a new INSERT on the same
1246**          database connection while the [sqlite3_last_insert_rowid()]
1247**          function is running and thus changes the last insert rowid,
1248**          then the value returned by [sqlite3_last_insert_rowid()] is
1249**          unpredictable and might not equal either the old or the new
1250**          last insert rowid.
1251*/
1252sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
1253
1254/*
1255** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
1256**
1257** This function returns the number of database rows that were changed
1258** or inserted or deleted by the most recently completed SQL statement
1259** on the [database connection] specified by the first parameter.
1260** Only changes that are directly specified by the INSERT, UPDATE,
1261** or DELETE statement are counted.  Auxiliary changes caused by
1262** triggers are not counted. Use the [sqlite3_total_changes()] function
1263** to find the total number of changes including changes caused by triggers.
1264**
1265** A "row change" is a change to a single row of a single table
1266** caused by an INSERT, DELETE, or UPDATE statement.  Rows that
1267** are changed as side effects of REPLACE constraint resolution,
1268** rollback, ABORT processing, DROP TABLE, or by any other
1269** mechanisms do not count as direct row changes.
1270**
1271** A "trigger context" is a scope of execution that begins and
1272** ends with the script of a trigger.  Most SQL statements are
1273** evaluated outside of any trigger.  This is the "top level"
1274** trigger context.  If a trigger fires from the top level, a
1275** new trigger context is entered for the duration of that one
1276** trigger.  Subtriggers create subcontexts for their duration.
1277**
1278** Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
1279** not create a new trigger context.
1280**
1281** This function returns the number of direct row changes in the
1282** most recent INSERT, UPDATE, or DELETE statement within the same
1283** trigger context.
1284**
1285** Thus, when called from the top level, this function returns the
1286** number of changes in the most recent INSERT, UPDATE, or DELETE
1287** that also occurred at the top level.  Within the body of a trigger,
1288** the sqlite3_changes() interface can be called to find the number of
1289** changes in the most recently completed INSERT, UPDATE, or DELETE
1290** statement within the body of the same trigger.
1291** However, the number returned does not include changes
1292** caused by subtriggers since those have their own context.
1293**
1294** SQLite implements the command "DELETE FROM table" without a WHERE clause
1295** by dropping and recreating the table.  (This is much faster than going
1296** through and deleting individual elements from the table.)  Because of this
1297** optimization, the deletions in "DELETE FROM table" are not row changes and
1298** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
1299** functions, regardless of the number of elements that were originally
1300** in the table.  To get an accurate count of the number of rows deleted, use
1301** "DELETE FROM table WHERE 1" instead.
1302**
1303** INVARIANTS:
1304**
1305** {H12241} The [sqlite3_changes()] function shall return the number of
1306**          row changes caused by the most recent INSERT, UPDATE,
1307**          or DELETE statement on the same database connection and
1308**          within the same or higher trigger context, or zero if there have
1309**          not been any qualifying row changes.
1310**
1311** {H12243} Statements of the form "DELETE FROM tablename" with no
1312**          WHERE clause shall cause subsequent calls to
1313**          [sqlite3_changes()] to return zero, regardless of the
1314**          number of rows originally in the table.
1315**
1316** ASSUMPTIONS:
1317**
1318** {A12252} If a separate thread makes changes on the same database connection
1319**          while [sqlite3_changes()] is running then the value returned
1320**          is unpredictable and not meaningful.
1321*/
1322int sqlite3_changes(sqlite3*);
1323
1324/*
1325** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600>
1326**
1327** This function returns the number of row changes caused by INSERT,
1328** UPDATE or DELETE statements since the [database connection] was opened.
1329** The count includes all changes from all trigger contexts.  However,
1330** the count does not include changes used to implement REPLACE constraints,
1331** do rollbacks or ABORT processing, or DROP table processing.
1332** The changes are counted as soon as the statement that makes them is
1333** completed (when the statement handle is passed to [sqlite3_reset()] or
1334** [sqlite3_finalize()]).
1335**
1336** SQLite implements the command "DELETE FROM table" without a WHERE clause
1337** by dropping and recreating the table.  (This is much faster than going
1338** through and deleting individual elements from the table.)  Because of this
1339** optimization, the deletions in "DELETE FROM table" are not row changes and
1340** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
1341** functions, regardless of the number of elements that were originally
1342** in the table.  To get an accurate count of the number of rows deleted, use
1343** "DELETE FROM table WHERE 1" instead.
1344**
1345** See also the [sqlite3_changes()] interface.
1346**
1347** INVARIANTS:
1348**
1349** {H12261} The [sqlite3_total_changes()] returns the total number
1350**          of row changes caused by INSERT, UPDATE, and/or DELETE
1351**          statements on the same [database connection], in any
1352**          trigger context, since the database connection was created.
1353**
1354** {H12263} Statements of the form "DELETE FROM tablename" with no
1355**          WHERE clause shall not change the value returned
1356**          by [sqlite3_total_changes()].
1357**
1358** ASSUMPTIONS:
1359**
1360** {A12264} If a separate thread makes changes on the same database connection
1361**          while [sqlite3_total_changes()] is running then the value
1362**          returned is unpredictable and not meaningful.
1363*/
1364int sqlite3_total_changes(sqlite3*);
1365
1366/*
1367** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500>
1368**
1369** This function causes any pending database operation to abort and
1370** return at its earliest opportunity. This routine is typically
1371** called in response to a user action such as pressing "Cancel"
1372** or Ctrl-C where the user wants a long query operation to halt
1373** immediately.
1374**
1375** It is safe to call this routine from a thread different from the
1376** thread that is currently running the database operation.  But it
1377** is not safe to call this routine with a [database connection] that
1378** is closed or might close before sqlite3_interrupt() returns.
1379**
1380** If an SQL operation is very nearly finished at the time when
1381** sqlite3_interrupt() is called, then it might not have an opportunity
1382** to be interrupted and might continue to completion.
1383**
1384** An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
1385** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
1386** that is inside an explicit transaction, then the entire transaction
1387** will be rolled back automatically.
1388**
1389** A call to sqlite3_interrupt() has no effect on SQL statements
1390** that are started after sqlite3_interrupt() returns.
1391**
1392** INVARIANTS:
1393**
1394** {H12271} The [sqlite3_interrupt()] interface will force all running
1395**          SQL statements associated with the same database connection
1396**          to halt after processing at most one additional row of data.
1397**
1398** {H12272} Any SQL statement that is interrupted by [sqlite3_interrupt()]
1399**          will return [SQLITE_INTERRUPT].
1400**
1401** ASSUMPTIONS:
1402**
1403** {A12279} If the database connection closes while [sqlite3_interrupt()]
1404**          is running then bad things will likely happen.
1405*/
1406void sqlite3_interrupt(sqlite3*);
1407
1408/*
1409** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200>
1410**
1411** These routines are useful for command-line input to determine if the
1412** currently entered text seems to form complete a SQL statement or
1413** if additional input is needed before sending the text into
1414** SQLite for parsing.  These routines return true if the input string
1415** appears to be a complete SQL statement.  A statement is judged to be
1416** complete if it ends with a semicolon token and is not a fragment of a
1417** CREATE TRIGGER statement.  Semicolons that are embedded within
1418** string literals or quoted identifier names or comments are not
1419** independent tokens (they are part of the token in which they are
1420** embedded) and thus do not count as a statement terminator.
1421**
1422** These routines do not parse the SQL statements thus
1423** will not detect syntactically incorrect SQL.
1424**
1425** INVARIANTS:
1426**
1427** {H10511} A successful evaluation of [sqlite3_complete()] or
1428**          [sqlite3_complete16()] functions shall
1429**          return a numeric 1 if and only if the last non-whitespace
1430**          token in their input is a semicolon that is not in between
1431**          the BEGIN and END of a CREATE TRIGGER statement.
1432**
1433** {H10512} If a memory allocation error occurs during an invocation
1434**          of [sqlite3_complete()] or [sqlite3_complete16()] then the
1435**          routine shall return [SQLITE_NOMEM].
1436**
1437** ASSUMPTIONS:
1438**
1439** {A10512} The input to [sqlite3_complete()] must be a zero-terminated
1440**          UTF-8 string.
1441**
1442** {A10513} The input to [sqlite3_complete16()] must be a zero-terminated
1443**          UTF-16 string in native byte order.
1444*/
1445int sqlite3_complete(const char *sql);
1446int sqlite3_complete16(const void *sql);
1447
1448/*
1449** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400>
1450**
1451** This routine sets a callback function that might be invoked whenever
1452** an attempt is made to open a database table that another thread
1453** or process has locked.
1454**
1455** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
1456** is returned immediately upon encountering the lock. If the busy callback
1457** is not NULL, then the callback will be invoked with two arguments.
1458**
1459** The first argument to the handler is a copy of the void* pointer which
1460** is the third argument to sqlite3_busy_handler().  The second argument to
1461** the handler callback is the number of times that the busy handler has
1462** been invoked for this locking event.  If the
1463** busy callback returns 0, then no additional attempts are made to
1464** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
1465** If the callback returns non-zero, then another attempt
1466** is made to open the database for reading and the cycle repeats.
1467**
1468** The presence of a busy handler does not guarantee that it will be invoked
1469** when there is lock contention. If SQLite determines that invoking the busy
1470** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1471** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
1472** Consider a scenario where one process is holding a read lock that
1473** it is trying to promote to a reserved lock and
1474** a second process is holding a reserved lock that it is trying
1475** to promote to an exclusive lock.  The first process cannot proceed
1476** because it is blocked by the second and the second process cannot
1477** proceed because it is blocked by the first.  If both processes
1478** invoke the busy handlers, neither will make any progress.  Therefore,
1479** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
1480** will induce the first process to release its read lock and allow
1481** the second process to proceed.
1482**
1483** The default busy callback is NULL.
1484**
1485** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
1486** when SQLite is in the middle of a large transaction where all the
1487** changes will not fit into the in-memory cache.  SQLite will
1488** already hold a RESERVED lock on the database file, but it needs
1489** to promote this lock to EXCLUSIVE so that it can spill cache
1490** pages into the database file without harm to concurrent
1491** readers.  If it is unable to promote the lock, then the in-memory
1492** cache will be left in an inconsistent state and so the error
1493** code is promoted from the relatively benign [SQLITE_BUSY] to
1494** the more severe [SQLITE_IOERR_BLOCKED].  This error code promotion
1495** forces an automatic rollback of the changes.  See the
1496** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
1497** CorruptionFollowingBusyError</a> wiki page for a discussion of why
1498** this is important.
1499**
1500** There can only be a single busy handler defined for each
1501** [database connection].  Setting a new busy handler clears any
1502** previously set handler.  Note that calling [sqlite3_busy_timeout()]
1503** will also set or clear the busy handler.
1504**
1505** INVARIANTS:
1506**
1507** {H12311} The [sqlite3_busy_handler(D,C,A)] function shall replace
1508**          busy callback in the [database connection] D with a new
1509**          a new busy handler C and application data pointer A.
1510**
1511** {H12312} Newly created [database connections] shall have a busy
1512**          handler of NULL.
1513**
1514** {H12314} When two or more [database connections] share a
1515**          [sqlite3_enable_shared_cache | common cache],
1516**          the busy handler for the database connection currently using
1517**          the cache shall be invoked when the cache encounters a lock.
1518**
1519** {H12316} If a busy handler callback returns zero, then the SQLite interface
1520**          that provoked the locking event shall return [SQLITE_BUSY].
1521**
1522** {H12318} SQLite shall invokes the busy handler with two arguments which
1523**          are a copy of the pointer supplied by the 3rd parameter to
1524**          [sqlite3_busy_handler()] and a count of the number of prior
1525**          invocations of the busy handler for the same locking event.
1526**
1527** ASSUMPTIONS:
1528**
1529** {A12319} A busy handler must not close the database connection
1530**          or [prepared statement] that invoked the busy handler.
1531*/
1532int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
1533
1534/*
1535** CAPI3REF: Set A Busy Timeout {H12340} <S40410>
1536**
1537** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
1538** for a specified amount of time when a table is locked.  The handler
1539** will sleep multiple times until at least "ms" milliseconds of sleeping
1540** have accumulated. {H12343} After "ms" milliseconds of sleeping,
1541** the handler returns 0 which causes [sqlite3_step()] to return
1542** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
1543**
1544** Calling this routine with an argument less than or equal to zero
1545** turns off all busy handlers.
1546**
1547** There can only be a single busy handler for a particular
1548** [database connection] any any given moment.  If another busy handler
1549** was defined  (using [sqlite3_busy_handler()]) prior to calling
1550** this routine, that other busy handler is cleared.
1551**
1552** INVARIANTS:
1553**
1554** {H12341} The [sqlite3_busy_timeout()] function shall override any prior
1555**          [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting
1556**          on the same [database connection].
1557**
1558** {H12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than
1559**          or equal to zero, then the busy handler shall be cleared so that
1560**          all subsequent locking events immediately return [SQLITE_BUSY].
1561**
1562** {H12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive
1563**          number N, then a busy handler shall be set that repeatedly calls
1564**          the xSleep() method in the [sqlite3_vfs | VFS interface] until
1565**          either the lock clears or until the cumulative sleep time
1566**          reported back by xSleep() exceeds N milliseconds.
1567*/
1568int sqlite3_busy_timeout(sqlite3*, int ms);
1569
1570/*
1571** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000>
1572**
1573** Definition: A <b>result table</b> is memory data structure created by the
1574** [sqlite3_get_table()] interface.  A result table records the
1575** complete query results from one or more queries.
1576**
1577** The table conceptually has a number of rows and columns.  But
1578** these numbers are not part of the result table itself.  These
1579** numbers are obtained separately.  Let N be the number of rows
1580** and M be the number of columns.
1581**
1582** A result table is an array of pointers to zero-terminated UTF-8 strings.
1583** There are (N+1)*M elements in the array.  The first M pointers point
1584** to zero-terminated strings that  contain the names of the columns.
1585** The remaining entries all point to query results.  NULL values result
1586** in NULL pointers.  All other values are in their UTF-8 zero-terminated
1587** string representation as returned by [sqlite3_column_text()].
1588**
1589** A result table might consist of one or more memory allocations.
1590** It is not safe to pass a result table directly to [sqlite3_free()].
1591** A result table should be deallocated using [sqlite3_free_table()].
1592**
1593** As an example of the result table format, suppose a query result
1594** is as follows:
1595**
1596** <blockquote><pre>
1597**        Name        | Age
1598**        -----------------------
1599**        Alice       | 43
1600**        Bob         | 28
1601**        Cindy       | 21
1602** </pre></blockquote>
1603**
1604** There are two column (M==2) and three rows (N==3).  Thus the
1605** result table has 8 entries.  Suppose the result table is stored
1606** in an array names azResult.  Then azResult holds this content:
1607**
1608** <blockquote><pre>
1609**        azResult&#91;0] = "Name";
1610**        azResult&#91;1] = "Age";
1611**        azResult&#91;2] = "Alice";
1612**        azResult&#91;3] = "43";
1613**        azResult&#91;4] = "Bob";
1614**        azResult&#91;5] = "28";
1615**        azResult&#91;6] = "Cindy";
1616**        azResult&#91;7] = "21";
1617** </pre></blockquote>
1618**
1619** The sqlite3_get_table() function evaluates one or more
1620** semicolon-separated SQL statements in the zero-terminated UTF-8
1621** string of its 2nd parameter.  It returns a result table to the
1622** pointer given in its 3rd parameter.
1623**
1624** After the calling function has finished using the result, it should
1625** pass the pointer to the result table to sqlite3_free_table() in order to
1626** release the memory that was malloced.  Because of the way the
1627** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
1628** function must not try to call [sqlite3_free()] directly.  Only
1629** [sqlite3_free_table()] is able to release the memory properly and safely.
1630**
1631** The sqlite3_get_table() interface is implemented as a wrapper around
1632** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
1633** to any internal data structures of SQLite.  It uses only the public
1634** interface defined here.  As a consequence, errors that occur in the
1635** wrapper layer outside of the internal [sqlite3_exec()] call are not
1636** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()].
1637**
1638** INVARIANTS:
1639**
1640** {H12371} If a [sqlite3_get_table()] fails a memory allocation, then
1641**          it shall free the result table under construction, abort the
1642**          query in process, skip any subsequent queries, set the
1643**          *pazResult output pointer to NULL and return [SQLITE_NOMEM].
1644**
1645** {H12373} If the pnColumn parameter to [sqlite3_get_table()] is not NULL
1646**          then a successful invocation of [sqlite3_get_table()] shall
1647**          write the number of columns in the
1648**          result set of the query into *pnColumn.
1649**
1650** {H12374} If the pnRow parameter to [sqlite3_get_table()] is not NULL
1651**          then a successful invocation of [sqlite3_get_table()] shall
1652**          writes the number of rows in the
1653**          result set of the query into *pnRow.
1654**
1655** {H12376} A successful invocation of [sqlite3_get_table()] that computes
1656**          N rows of result with C columns per row shall make *pazResult
1657**          point to an array of pointers to (N+1)*C strings where the first
1658**          C strings are column names as obtained from
1659**          [sqlite3_column_name()] and the rest are column result values
1660**          obtained from [sqlite3_column_text()].
1661**
1662** {H12379} The values in the pazResult array returned by [sqlite3_get_table()]
1663**          shall remain valid until cleared by [sqlite3_free_table()].
1664**
1665** {H12382} When an error occurs during evaluation of [sqlite3_get_table()]
1666**          the function shall set *pazResult to NULL, write an error message
1667**          into memory obtained from [sqlite3_malloc()], make
1668**          **pzErrmsg point to that error message, and return a
1669**          appropriate [error code].
1670*/
1671int sqlite3_get_table(
1672  sqlite3 *db,          /* An open database */
1673  const char *zSql,     /* SQL to be evaluated */
1674  char ***pazResult,    /* Results of the query */
1675  int *pnRow,           /* Number of result rows written here */
1676  int *pnColumn,        /* Number of result columns written here */
1677  char **pzErrmsg       /* Error msg written here */
1678);
1679void sqlite3_free_table(char **result);
1680
1681/*
1682** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000>
1683**
1684** These routines are workalikes of the "printf()" family of functions
1685** from the standard C library.
1686**
1687** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
1688** results into memory obtained from [sqlite3_malloc()].
1689** The strings returned by these two routines should be
1690** released by [sqlite3_free()].  Both routines return a
1691** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
1692** memory to hold the resulting string.
1693**
1694** In sqlite3_snprintf() routine is similar to "snprintf()" from
1695** the standard C library.  The result is written into the
1696** buffer supplied as the second parameter whose size is given by
1697** the first parameter. Note that the order of the
1698** first two parameters is reversed from snprintf().  This is an
1699** historical accident that cannot be fixed without breaking
1700** backwards compatibility.  Note also that sqlite3_snprintf()
1701** returns a pointer to its buffer instead of the number of
1702** characters actually written into the buffer.  We admit that
1703** the number of characters written would be a more useful return
1704** value but we cannot change the implementation of sqlite3_snprintf()
1705** now without breaking compatibility.
1706**
1707** As long as the buffer size is greater than zero, sqlite3_snprintf()
1708** guarantees that the buffer is always zero-terminated.  The first
1709** parameter "n" is the total size of the buffer, including space for
1710** the zero terminator.  So the longest string that can be completely
1711** written will be n-1 characters.
1712**
1713** These routines all implement some additional formatting
1714** options that are useful for constructing SQL statements.
1715** All of the usual printf() formatting options apply.  In addition, there
1716** is are "%q", "%Q", and "%z" options.
1717**
1718** The %q option works like %s in that it substitutes a null-terminated
1719** string from the argument list.  But %q also doubles every '\'' character.
1720** %q is designed for use inside a string literal.  By doubling each '\''
1721** character it escapes that character and allows it to be inserted into
1722** the string.
1723**
1724** For example, assume the string variable zText contains text as follows:
1725**
1726** <blockquote><pre>
1727**  char *zText = "It's a happy day!";
1728** </pre></blockquote>
1729**
1730** One can use this text in an SQL statement as follows:
1731**
1732** <blockquote><pre>
1733**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
1734**  sqlite3_exec(db, zSQL, 0, 0, 0);
1735**  sqlite3_free(zSQL);
1736** </pre></blockquote>
1737**
1738** Because the %q format string is used, the '\'' character in zText
1739** is escaped and the SQL generated is as follows:
1740**
1741** <blockquote><pre>
1742**  INSERT INTO table1 VALUES('It''s a happy day!')
1743** </pre></blockquote>
1744**
1745** This is correct.  Had we used %s instead of %q, the generated SQL
1746** would have looked like this:
1747**
1748** <blockquote><pre>
1749**  INSERT INTO table1 VALUES('It's a happy day!');
1750** </pre></blockquote>
1751**
1752** This second example is an SQL syntax error.  As a general rule you should
1753** always use %q instead of %s when inserting text into a string literal.
1754**
1755** The %Q option works like %q except it also adds single quotes around
1756** the outside of the total string.  Additionally, if the parameter in the
1757** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
1758** single quotes) in place of the %Q option.  So, for example, one could say:
1759**
1760** <blockquote><pre>
1761**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
1762**  sqlite3_exec(db, zSQL, 0, 0, 0);
1763**  sqlite3_free(zSQL);
1764** </pre></blockquote>
1765**
1766** The code above will render a correct SQL statement in the zSQL
1767** variable even if the zText variable is a NULL pointer.
1768**
1769** The "%z" formatting option works exactly like "%s" with the
1770** addition that after the string has been read and copied into
1771** the result, [sqlite3_free()] is called on the input string. {END}
1772**
1773** INVARIANTS:
1774**
1775** {H17403}  The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces
1776**           return either pointers to zero-terminated UTF-8 strings held in
1777**           memory obtained from [sqlite3_malloc()] or NULL pointers if
1778**           a call to [sqlite3_malloc()] fails.
1779**
1780** {H17406}  The [sqlite3_snprintf()] interface writes a zero-terminated
1781**           UTF-8 string into the buffer pointed to by the second parameter
1782**           provided that the first parameter is greater than zero.
1783**
1784** {H17407}  The [sqlite3_snprintf()] interface does not write slots of
1785**           its output buffer (the second parameter) outside the range
1786**           of 0 through N-1 (where N is the first parameter)
1787**           regardless of the length of the string
1788**           requested by the format specification.
1789*/
1790char *sqlite3_mprintf(const char*,...);
1791char *sqlite3_vmprintf(const char*, va_list);
1792char *sqlite3_snprintf(int,char*,const char*, ...);
1793
1794/*
1795** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000>
1796**
1797** The SQLite core  uses these three routines for all of its own
1798** internal memory allocation needs. "Core" in the previous sentence
1799** does not include operating-system specific VFS implementation.  The
1800** Windows VFS uses native malloc() and free() for some operations.
1801**
1802** The sqlite3_malloc() routine returns a pointer to a block
1803** of memory at least N bytes in length, where N is the parameter.
1804** If sqlite3_malloc() is unable to obtain sufficient free
1805** memory, it returns a NULL pointer.  If the parameter N to
1806** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
1807** a NULL pointer.
1808**
1809** Calling sqlite3_free() with a pointer previously returned
1810** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
1811** that it might be reused.  The sqlite3_free() routine is
1812** a no-op if is called with a NULL pointer.  Passing a NULL pointer
1813** to sqlite3_free() is harmless.  After being freed, memory
1814** should neither be read nor written.  Even reading previously freed
1815** memory might result in a segmentation fault or other severe error.
1816** Memory corruption, a segmentation fault, or other severe error
1817** might result if sqlite3_free() is called with a non-NULL pointer that
1818** was not obtained from sqlite3_malloc() or sqlite3_free().
1819**
1820** The sqlite3_realloc() interface attempts to resize a
1821** prior memory allocation to be at least N bytes, where N is the
1822** second parameter.  The memory allocation to be resized is the first
1823** parameter.  If the first parameter to sqlite3_realloc()
1824** is a NULL pointer then its behavior is identical to calling
1825** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
1826** If the second parameter to sqlite3_realloc() is zero or
1827** negative then the behavior is exactly the same as calling
1828** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
1829** sqlite3_realloc() returns a pointer to a memory allocation
1830** of at least N bytes in size or NULL if sufficient memory is unavailable.
1831** If M is the size of the prior allocation, then min(N,M) bytes
1832** of the prior allocation are copied into the beginning of buffer returned
1833** by sqlite3_realloc() and the prior allocation is freed.
1834** If sqlite3_realloc() returns NULL, then the prior allocation
1835** is not freed.
1836**
1837** The memory returned by sqlite3_malloc() and sqlite3_realloc()
1838** is always aligned to at least an 8 byte boundary. {END}
1839**
1840** The default implementation of the memory allocation subsystem uses
1841** the malloc(), realloc() and free() provided by the standard C library.
1842** {H17382} However, if SQLite is compiled with the
1843** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i>
1844** is an integer), then SQLite create a static array of at least
1845** <i>NNN</i> bytes in size and uses that array for all of its dynamic
1846** memory allocation needs. {END}  Additional memory allocator options
1847** may be added in future releases.
1848**
1849** In SQLite version 3.5.0 and 3.5.1, it was possible to define
1850** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
1851** implementation of these routines to be omitted.  That capability
1852** is no longer provided.  Only built-in memory allocators can be used.
1853**
1854** The Windows OS interface layer calls
1855** the system malloc() and free() directly when converting
1856** filenames between the UTF-8 encoding used by SQLite
1857** and whatever filename encoding is used by the particular Windows
1858** installation.  Memory allocation errors are detected, but
1859** they are reported back as [SQLITE_CANTOPEN] or
1860** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
1861**
1862** INVARIANTS:
1863**
1864** {H17303}  The [sqlite3_malloc(N)] interface returns either a pointer to
1865**           a newly checked-out block of at least N bytes of memory
1866**           that is 8-byte aligned, or it returns NULL if it is unable
1867**           to fulfill the request.
1868**
1869** {H17304}  The [sqlite3_malloc(N)] interface returns a NULL pointer if
1870**           N is less than or equal to zero.
1871**
1872** {H17305}  The [sqlite3_free(P)] interface releases memory previously
1873**           returned from [sqlite3_malloc()] or [sqlite3_realloc()],
1874**           making it available for reuse.
1875**
1876** {H17306}  A call to [sqlite3_free(NULL)] is a harmless no-op.
1877**
1878** {H17310}  A call to [sqlite3_realloc(0,N)] is equivalent to a call
1879**           to [sqlite3_malloc(N)].
1880**
1881** {H17312}  A call to [sqlite3_realloc(P,0)] is equivalent to a call
1882**           to [sqlite3_free(P)].
1883**
1884** {H17315}  The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()],
1885**           and [sqlite3_free()] for all of its memory allocation and
1886**           deallocation needs.
1887**
1888** {H17318}  The [sqlite3_realloc(P,N)] interface returns either a pointer
1889**           to a block of checked-out memory of at least N bytes in size
1890**           that is 8-byte aligned, or a NULL pointer.
1891**
1892** {H17321}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
1893**           copies the first K bytes of content from P into the newly
1894**           allocated block, where K is the lesser of N and the size of
1895**           the buffer P.
1896**
1897** {H17322}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
1898**           releases the buffer P.
1899**
1900** {H17323}  When [sqlite3_realloc(P,N)] returns NULL, the buffer P is
1901**           not modified or released.
1902**
1903** ASSUMPTIONS:
1904**
1905** {A17350}  The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
1906**           must be either NULL or else pointers obtained from a prior
1907**           invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
1908**           not yet been released.
1909**
1910** {A17351}  The application must not read or write any part of
1911**           a block of memory after it has been released using
1912**           [sqlite3_free()] or [sqlite3_realloc()].
1913*/
1914void *sqlite3_malloc(int);
1915void *sqlite3_realloc(void*, int);
1916void sqlite3_free(void*);
1917
1918/*
1919** CAPI3REF: Memory Allocator Statistics {H17370} <S30210>
1920**
1921** SQLite provides these two interfaces for reporting on the status
1922** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
1923** routines, which form the built-in memory allocation subsystem.
1924**
1925** INVARIANTS:
1926**
1927** {H17371} The [sqlite3_memory_used()] routine returns the number of bytes
1928**          of memory currently outstanding (malloced but not freed).
1929**
1930** {H17373} The [sqlite3_memory_highwater()] routine returns the maximum
1931**          value of [sqlite3_memory_used()] since the high-water mark
1932**          was last reset.
1933**
1934** {H17374} The values returned by [sqlite3_memory_used()] and
1935**          [sqlite3_memory_highwater()] include any overhead
1936**          added by SQLite in its implementation of [sqlite3_malloc()],
1937**          but not overhead added by the any underlying system library
1938**          routines that [sqlite3_malloc()] may call.
1939**
1940** {H17375} The memory high-water mark is reset to the current value of
1941**          [sqlite3_memory_used()] if and only if the parameter to
1942**          [sqlite3_memory_highwater()] is true.  The value returned
1943**          by [sqlite3_memory_highwater(1)] is the high-water mark
1944**          prior to the reset.
1945*/
1946sqlite3_int64 sqlite3_memory_used(void);
1947sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
1948
1949/*
1950** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000>
1951**
1952** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
1953** select random ROWIDs when inserting new records into a table that
1954** already uses the largest possible ROWID.  The PRNG is also used for
1955** the build-in random() and randomblob() SQL functions.  This interface allows
1956** applications to access the same PRNG for other purposes.
1957**
1958** A call to this routine stores N bytes of randomness into buffer P.
1959**
1960** The first time this routine is invoked (either internally or by
1961** the application) the PRNG is seeded using randomness obtained
1962** from the xRandomness method of the default [sqlite3_vfs] object.
1963** On all subsequent invocations, the pseudo-randomness is generated
1964** internally and without recourse to the [sqlite3_vfs] xRandomness
1965** method.
1966**
1967** INVARIANTS:
1968**
1969** {H17392} The [sqlite3_randomness(N,P)] interface writes N bytes of
1970**          high-quality pseudo-randomness into buffer P.
1971*/
1972void sqlite3_randomness(int N, void *P);
1973
1974/*
1975** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100>
1976**
1977** This routine registers a authorizer callback with a particular
1978** [database connection], supplied in the first argument.
1979** The authorizer callback is invoked as SQL statements are being compiled
1980** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
1981** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()].  At various
1982** points during the compilation process, as logic is being created
1983** to perform various actions, the authorizer callback is invoked to
1984** see if those actions are allowed.  The authorizer callback should
1985** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
1986** specific action but allow the SQL statement to continue to be
1987** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
1988** rejected with an error.  If the authorizer callback returns
1989** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
1990** then the [sqlite3_prepare_v2()] or equivalent call that triggered
1991** the authorizer will fail with an error message.
1992**
1993** When the callback returns [SQLITE_OK], that means the operation
1994** requested is ok.  When the callback returns [SQLITE_DENY], the
1995** [sqlite3_prepare_v2()] or equivalent call that triggered the
1996** authorizer will fail with an error message explaining that
1997** access is denied.  If the authorizer code is [SQLITE_READ]
1998** and the callback returns [SQLITE_IGNORE] then the
1999** [prepared statement] statement is constructed to substitute
2000** a NULL value in place of the table column that would have
2001** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
2002** return can be used to deny an untrusted user access to individual
2003** columns of a table.
2004**
2005** The first parameter to the authorizer callback is a copy of the third
2006** parameter to the sqlite3_set_authorizer() interface. The second parameter
2007** to the callback is an integer [SQLITE_COPY | action code] that specifies
2008** the particular action to be authorized. The third through sixth parameters
2009** to the callback are zero-terminated strings that contain additional
2010** details about the action to be authorized.
2011**
2012** An authorizer is used when [sqlite3_prepare | preparing]
2013** SQL statements from an untrusted source, to ensure that the SQL statements
2014** do not try to access data they are not allowed to see, or that they do not
2015** try to execute malicious statements that damage the database.  For
2016** example, an application may allow a user to enter arbitrary
2017** SQL queries for evaluation by a database.  But the application does
2018** not want the user to be able to make arbitrary changes to the
2019** database.  An authorizer could then be put in place while the
2020** user-entered SQL is being [sqlite3_prepare | prepared] that
2021** disallows everything except [SELECT] statements.
2022**
2023** Applications that need to process SQL from untrusted sources
2024** might also consider lowering resource limits using [sqlite3_limit()]
2025** and limiting database size using the [max_page_count] [PRAGMA]
2026** in addition to using an authorizer.
2027**
2028** Only a single authorizer can be in place on a database connection
2029** at a time.  Each call to sqlite3_set_authorizer overrides the
2030** previous call.  Disable the authorizer by installing a NULL callback.
2031** The authorizer is disabled by default.
2032**
2033** Note that the authorizer callback is invoked only during
2034** [sqlite3_prepare()] or its variants.  Authorization is not
2035** performed during statement evaluation in [sqlite3_step()].
2036**
2037** INVARIANTS:
2038**
2039** {H12501} The [sqlite3_set_authorizer(D,...)] interface registers a
2040**          authorizer callback with database connection D.
2041**
2042** {H12502} The authorizer callback is invoked as SQL statements are
2043**          being compiled.
2044**
2045** {H12503} If the authorizer callback returns any value other than
2046**          [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY], then
2047**          the [sqlite3_prepare_v2()] or equivalent call that caused
2048**          the authorizer callback to run shall fail with an
2049**          [SQLITE_ERROR] error code and an appropriate error message.
2050**
2051** {H12504} When the authorizer callback returns [SQLITE_OK], the operation
2052**          described is processed normally.
2053**
2054** {H12505} When the authorizer callback returns [SQLITE_DENY], the
2055**          [sqlite3_prepare_v2()] or equivalent call that caused the
2056**          authorizer callback to run shall fail
2057**          with an [SQLITE_ERROR] error code and an error message
2058**          explaining that access is denied.
2059**
2060** {H12506} If the authorizer code (the 2nd parameter to the authorizer
2061**          callback) is [SQLITE_READ] and the authorizer callback returns
2062**          [SQLITE_IGNORE], then the prepared statement is constructed to
2063**          insert a NULL value in place of the table column that would have
2064**          been read if [SQLITE_OK] had been returned.
2065**
2066** {H12507} If the authorizer code (the 2nd parameter to the authorizer
2067**          callback) is anything other than [SQLITE_READ], then
2068**          a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY].
2069**
2070** {H12510} The first parameter to the authorizer callback is a copy of
2071**          the third parameter to the [sqlite3_set_authorizer()] interface.
2072**
2073** {H12511} The second parameter to the callback is an integer
2074**          [SQLITE_COPY | action code] that specifies the particular action
2075**          to be authorized.
2076**
2077** {H12512} The third through sixth parameters to the callback are
2078**          zero-terminated strings that contain
2079**          additional details about the action to be authorized.
2080**
2081** {H12520} Each call to [sqlite3_set_authorizer()] overrides
2082**          any previously installed authorizer.
2083**
2084** {H12521} A NULL authorizer means that no authorization
2085**          callback is invoked.
2086**
2087** {H12522} The default authorizer is NULL.
2088*/
2089int sqlite3_set_authorizer(
2090  sqlite3*,
2091  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
2092  void *pUserData
2093);
2094
2095/*
2096** CAPI3REF: Authorizer Return Codes {H12590} <H12500>
2097**
2098** The [sqlite3_set_authorizer | authorizer callback function] must
2099** return either [SQLITE_OK] or one of these two constants in order
2100** to signal SQLite whether or not the action is permitted.  See the
2101** [sqlite3_set_authorizer | authorizer documentation] for additional
2102** information.
2103*/
2104#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
2105#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
2106
2107/*
2108** CAPI3REF: Authorizer Action Codes {H12550} <H12500>
2109**
2110** The [sqlite3_set_authorizer()] interface registers a callback function
2111** that is invoked to authorize certain SQL statement actions.  The
2112** second parameter to the callback is an integer code that specifies
2113** what action is being authorized.  These are the integer action codes that
2114** the authorizer callback may be passed.
2115**
2116** These action code values signify what kind of operation is to be
2117** authorized.  The 3rd and 4th parameters to the authorization
2118** callback function will be parameters or NULL depending on which of these
2119** codes is used as the second parameter.  The 5th parameter to the
2120** authorizer callback is the name of the database ("main", "temp",
2121** etc.) if applicable.  The 6th parameter to the authorizer callback
2122** is the name of the inner-most trigger or view that is responsible for
2123** the access attempt or NULL if this access attempt is directly from
2124** top-level SQL code.
2125**
2126** INVARIANTS:
2127**
2128** {H12551} The second parameter to an
2129**          [sqlite3_set_authorizer | authorizer callback] is always an integer
2130**          [SQLITE_COPY | authorizer code] that specifies what action
2131**          is being authorized.
2132**
2133** {H12552} The 3rd and 4th parameters to the
2134**          [sqlite3_set_authorizer | authorization callback]
2135**          will be parameters or NULL depending on which
2136**          [SQLITE_COPY | authorizer code] is used as the second parameter.
2137**
2138** {H12553} The 5th parameter to the
2139**          [sqlite3_set_authorizer | authorizer callback] is the name
2140**          of the database (example: "main", "temp", etc.) if applicable.
2141**
2142** {H12554} The 6th parameter to the
2143**          [sqlite3_set_authorizer | authorizer callback] is the name
2144**          of the inner-most trigger or view that is responsible for
2145**          the access attempt or NULL if this access attempt is directly from
2146**          top-level SQL code.
2147*/
2148/******************************************* 3rd ************ 4th ***********/
2149#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
2150#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
2151#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
2152#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
2153#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
2154#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
2155#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
2156#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
2157#define SQLITE_DELETE                9   /* Table Name      NULL            */
2158#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
2159#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
2160#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
2161#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
2162#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
2163#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
2164#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
2165#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
2166#define SQLITE_INSERT               18   /* Table Name      NULL            */
2167#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
2168#define SQLITE_READ                 20   /* Table Name      Column Name     */
2169#define SQLITE_SELECT               21   /* NULL            NULL            */
2170#define SQLITE_TRANSACTION          22   /* NULL            NULL            */
2171#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
2172#define SQLITE_ATTACH               24   /* Filename        NULL            */
2173#define SQLITE_DETACH               25   /* Database Name   NULL            */
2174#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
2175#define SQLITE_REINDEX              27   /* Index Name      NULL            */
2176#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
2177#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
2178#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
2179#define SQLITE_FUNCTION             31   /* Function Name   NULL            */
2180#define SQLITE_COPY                  0   /* No longer used */
2181
2182/*
2183** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400>
2184**
2185** These routines register callback functions that can be used for
2186** tracing and profiling the execution of SQL statements.
2187**
2188** The callback function registered by sqlite3_trace() is invoked at
2189** various times when an SQL statement is being run by [sqlite3_step()].
2190** The callback returns a UTF-8 rendering of the SQL statement text
2191** as the statement first begins executing.  Additional callbacks occur
2192** as each triggered subprogram is entered.  The callbacks for triggers
2193** contain a UTF-8 SQL comment that identifies the trigger.
2194**
2195** The callback function registered by sqlite3_profile() is invoked
2196** as each SQL statement finishes.  The profile callback contains
2197** the original statement text and an estimate of wall-clock time
2198** of how long that statement took to run.
2199**
2200** The sqlite3_profile() API is currently considered experimental and
2201** is subject to change or removal in a future release.
2202**
2203** The trigger reporting feature of the trace callback is considered
2204** experimental and is subject to change or removal in future releases.
2205** Future versions of SQLite might also add new trace callback
2206** invocations.
2207**
2208** INVARIANTS:
2209**
2210** {H12281} The callback function registered by [sqlite3_trace()] is
2211**          whenever an SQL statement first begins to execute and
2212**          whenever a trigger subprogram first begins to run.
2213**
2214** {H12282} Each call to [sqlite3_trace()] overrides the previously
2215**          registered trace callback.
2216**
2217** {H12283} A NULL trace callback disables tracing.
2218**
2219** {H12284} The first argument to the trace callback is a copy of
2220**          the pointer which was the 3rd argument to [sqlite3_trace()].
2221**
2222** {H12285} The second argument to the trace callback is a
2223**          zero-terminated UTF-8 string containing the original text
2224**          of the SQL statement as it was passed into [sqlite3_prepare_v2()]
2225**          or the equivalent, or an SQL comment indicating the beginning
2226**          of a trigger subprogram.
2227**
2228** {H12287} The callback function registered by [sqlite3_profile()] is invoked
2229**          as each SQL statement finishes.
2230**
2231** {H12288} The first parameter to the profile callback is a copy of
2232**          the 3rd parameter to [sqlite3_profile()].
2233**
2234** {H12289} The second parameter to the profile callback is a
2235**          zero-terminated UTF-8 string that contains the complete text of
2236**          the SQL statement as it was processed by [sqlite3_prepare_v2()]
2237**          or the equivalent.
2238**
2239** {H12290} The third parameter to the profile callback is an estimate
2240**          of the number of nanoseconds of wall-clock time required to
2241**          run the SQL statement from start to finish.
2242*/
2243void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
2244void *sqlite3_profile(sqlite3*,
2245   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
2246
2247/*
2248** CAPI3REF: Query Progress Callbacks {H12910} <S60400>
2249**
2250** This routine configures a callback function - the
2251** progress callback - that is invoked periodically during long
2252** running calls to [sqlite3_exec()], [sqlite3_step()] and
2253** [sqlite3_get_table()].  An example use for this
2254** interface is to keep a GUI updated during a large query.
2255**
2256** If the progress callback returns non-zero, the operation is
2257** interrupted.  This feature can be used to implement a
2258** "Cancel" button on a GUI dialog box.
2259**
2260** INVARIANTS:
2261**
2262** {H12911} The callback function registered by sqlite3_progress_handler()
2263**          is invoked periodically during long running calls to
2264**          [sqlite3_step()].
2265**
2266** {H12912} The progress callback is invoked once for every N virtual
2267**          machine opcodes, where N is the second argument to
2268**          the [sqlite3_progress_handler()] call that registered
2269**          the callback.  If N is less than 1, sqlite3_progress_handler()
2270**          acts as if a NULL progress handler had been specified.
2271**
2272** {H12913} The progress callback itself is identified by the third
2273**          argument to sqlite3_progress_handler().
2274**
2275** {H12914} The fourth argument to sqlite3_progress_handler() is a
2276**          void pointer passed to the progress callback
2277**          function each time it is invoked.
2278**
2279** {H12915} If a call to [sqlite3_step()] results in fewer than N opcodes
2280**          being executed, then the progress callback is never invoked.
2281**
2282** {H12916} Every call to [sqlite3_progress_handler()]
2283**          overwrites any previously registered progress handler.
2284**
2285** {H12917} If the progress handler callback is NULL then no progress
2286**          handler is invoked.
2287**
2288** {H12918} If the progress callback returns a result other than 0, then
2289**          the behavior is a if [sqlite3_interrupt()] had been called.
2290**          <S30500>
2291*/
2292void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
2293
2294/*
2295** CAPI3REF: Opening A New Database Connection {H12700} <S40200>
2296**
2297** These routines open an SQLite database file whose name is given by the
2298** filename argument. The filename argument is interpreted as UTF-8 for
2299** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
2300** order for sqlite3_open16(). A [database connection] handle is usually
2301** returned in *ppDb, even if an error occurs.  The only exception is that
2302** if SQLite is unable to allocate memory to hold the [sqlite3] object,
2303** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
2304** object. If the database is opened (and/or created) successfully, then
2305** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.  The
2306** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
2307** an English language description of the error.
2308**
2309** The default encoding for the database will be UTF-8 if
2310** sqlite3_open() or sqlite3_open_v2() is called and
2311** UTF-16 in the native byte order if sqlite3_open16() is used.
2312**
2313** Whether or not an error occurs when it is opened, resources
2314** associated with the [database connection] handle should be released by
2315** passing it to [sqlite3_close()] when it is no longer required.
2316**
2317** The sqlite3_open_v2() interface works like sqlite3_open()
2318** except that it accepts two additional parameters for additional control
2319** over the new database connection.  The flags parameter can take one of
2320** the following three values, optionally combined with the
2321** [SQLITE_OPEN_NOMUTEX] flag:
2322**
2323** <dl>
2324** <dt>[SQLITE_OPEN_READONLY]</dt>
2325** <dd>The database is opened in read-only mode.  If the database does not
2326** already exist, an error is returned.</dd>
2327**
2328** <dt>[SQLITE_OPEN_READWRITE]</dt>
2329** <dd>The database is opened for reading and writing if possible, or reading
2330** only if the file is write protected by the operating system.  In either
2331** case the database must already exist, otherwise an error is returned.</dd>
2332**
2333** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
2334** <dd>The database is opened for reading and writing, and is creates it if
2335** it does not already exist. This is the behavior that is always used for
2336** sqlite3_open() and sqlite3_open16().</dd>
2337** </dl>
2338**
2339** If the 3rd parameter to sqlite3_open_v2() is not one of the
2340** combinations shown above or one of the combinations shown above combined
2341** with the [SQLITE_OPEN_NOMUTEX] flag, then the behavior is undefined.
2342**
2343** If the [SQLITE_OPEN_NOMUTEX] flag is set, then mutexes on the
2344** opened [database connection] are disabled and the appliation must
2345** insure that access to the [database connection] and its associated
2346** [prepared statements] is serialized.  The [SQLITE_OPEN_NOMUTEX] flag
2347** is the default behavior is SQLite is configured using the
2348** [SQLITE_CONFIG_MULTITHREAD] or [SQLITE_CONFIG_SINGLETHREAD] options
2349** to [sqlite3_config()].  The [SQLITE_OPEN_NOMUTEX] flag only makes a
2350** difference when SQLite is in its default [SQLITE_CONFIG_SERIALIZED] mode.
2351**
2352** If the filename is ":memory:", then a private, temporary in-memory database
2353** is created for the connection.  This in-memory database will vanish when
2354** the database connection is closed.  Future versions of SQLite might
2355** make use of additional special filenames that begin with the ":" character.
2356** It is recommended that when a database filename actually does begin with
2357** a ":" character you should prefix the filename with a pathname such as
2358** "./" to avoid ambiguity.
2359**
2360** If the filename is an empty string, then a private, temporary
2361** on-disk database will be created.  This private database will be
2362** automatically deleted as soon as the database connection is closed.
2363**
2364** The fourth parameter to sqlite3_open_v2() is the name of the
2365** [sqlite3_vfs] object that defines the operating system interface that
2366** the new database connection should use.  If the fourth parameter is
2367** a NULL pointer then the default [sqlite3_vfs] object is used.
2368**
2369** <b>Note to Windows users:</b>  The encoding used for the filename argument
2370** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
2371** codepage is currently defined.  Filenames containing international
2372** characters must be converted to UTF-8 prior to passing them into
2373** sqlite3_open() or sqlite3_open_v2().
2374**
2375** INVARIANTS:
2376**
2377** {H12701} The [sqlite3_open()], [sqlite3_open16()], and
2378**          [sqlite3_open_v2()] interfaces create a new
2379**          [database connection] associated with
2380**          the database file given in their first parameter.
2381**
2382** {H12702} The filename argument is interpreted as UTF-8
2383**          for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
2384**          in the native byte order for [sqlite3_open16()].
2385**
2386** {H12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()],
2387**          or [sqlite3_open_v2()] writes a pointer to a new
2388**          [database connection] into *ppDb.
2389**
2390** {H12704} The [sqlite3_open()], [sqlite3_open16()], and
2391**          [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success,
2392**          or an appropriate [error code] on failure.
2393**
2394** {H12706} The default text encoding for a new database created using
2395**          [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8.
2396**
2397** {H12707} The default text encoding for a new database created using
2398**          [sqlite3_open16()] will be UTF-16.
2399**
2400** {H12709} The [sqlite3_open(F,D)] interface is equivalent to
2401**          [sqlite3_open_v2(F,D,G,0)] where the G parameter is
2402**          [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE].
2403**
2404** {H12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
2405**          bit value [SQLITE_OPEN_READONLY] then the database is opened
2406**          for reading only.
2407**
2408** {H12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
2409**          bit value [SQLITE_OPEN_READWRITE] then the database is opened
2410**          reading and writing if possible, or for reading only if the
2411**          file is write protected by the operating system.
2412**
2413** {H12713} If the G parameter to [sqlite3_open(v2(F,D,G,V)] omits the
2414**          bit value [SQLITE_OPEN_CREATE] and the database does not
2415**          previously exist, an error is returned.
2416**
2417** {H12714} If the G parameter to [sqlite3_open(v2(F,D,G,V)] contains the
2418**          bit value [SQLITE_OPEN_CREATE] and the database does not
2419**          previously exist, then an attempt is made to create and
2420**          initialize the database.
2421**
2422** {H12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()],
2423**          or [sqlite3_open_v2()] is ":memory:", then an private,
2424**          ephemeral, in-memory database is created for the connection.
2425**          <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
2426**          in sqlite3_open_v2()?</todo>
2427**
2428** {H12719} If the filename is NULL or an empty string, then a private,
2429**          ephemeral on-disk database will be created.
2430**          <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
2431**          in sqlite3_open_v2()?</todo>
2432**
2433** {H12721} The [database connection] created by [sqlite3_open_v2(F,D,G,V)]
2434**          will use the [sqlite3_vfs] object identified by the V parameter,
2435**          or the default [sqlite3_vfs] object if V is a NULL pointer.
2436**
2437** {H12723} Two [database connections] will share a common cache if both were
2438**          opened with the same VFS while [shared cache mode] was enabled and
2439**          if both filenames compare equal using memcmp() after having been
2440**          processed by the [sqlite3_vfs | xFullPathname] method of the VFS.
2441*/
2442int sqlite3_open(
2443  const char *filename,   /* Database filename (UTF-8) */
2444  sqlite3 **ppDb          /* OUT: SQLite db handle */
2445);
2446int sqlite3_open16(
2447  const void *filename,   /* Database filename (UTF-16) */
2448  sqlite3 **ppDb          /* OUT: SQLite db handle */
2449);
2450int sqlite3_open_v2(
2451  const char *filename,   /* Database filename (UTF-8) */
2452  sqlite3 **ppDb,         /* OUT: SQLite db handle */
2453  int flags,              /* Flags */
2454  const char *zVfs        /* Name of VFS module to use */
2455);
2456
2457/*
2458** CAPI3REF: Error Codes And Messages {H12800} <S60200>
2459**
2460** The sqlite3_errcode() interface returns the numeric [result code] or
2461** [extended result code] for the most recent failed sqlite3_* API call
2462** associated with a [database connection]. If a prior API call failed
2463** but the most recent API call succeeded, the return value from
2464** sqlite3_errcode() is undefined.
2465**
2466** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
2467** text that describes the error, as either UTF-8 or UTF-16 respectively.
2468** Memory to hold the error message string is managed internally.
2469** The application does not need to worry about freeing the result.
2470** However, the error string might be overwritten or deallocated by
2471** subsequent calls to other SQLite interface functions.
2472**
2473** If an interface fails with SQLITE_MISUSE, that means the interface
2474** was invoked incorrectly by the application.  In that case, the
2475** error code and message may or may not be set.
2476**
2477** INVARIANTS:
2478**
2479** {H12801} The [sqlite3_errcode(D)] interface returns the numeric
2480**          [result code] or [extended result code] for the most recently
2481**          failed interface call associated with the [database connection] D.
2482**
2483** {H12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
2484**          interfaces return English-language text that describes
2485**          the error in the mostly recently failed interface call,
2486**          encoded as either UTF-8 or UTF-16 respectively.
2487**
2488** {H12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
2489**          are valid until the next SQLite interface call.
2490**
2491** {H12808} Calls to API routines that do not return an error code
2492**          (example: [sqlite3_data_count()]) do not
2493**          change the error code or message returned by
2494**          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
2495**
2496** {H12809} Interfaces that are not associated with a specific
2497**          [database connection] (examples:
2498**          [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()]
2499**          do not change the values returned by
2500**          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
2501*/
2502int sqlite3_errcode(sqlite3 *db);
2503const char *sqlite3_errmsg(sqlite3*);
2504const void *sqlite3_errmsg16(sqlite3*);
2505
2506/*
2507** CAPI3REF: SQL Statement Object {H13000} <H13010>
2508** KEYWORDS: {prepared statement} {prepared statements}
2509**
2510** An instance of this object represents a single SQL statement.
2511** This object is variously known as a "prepared statement" or a
2512** "compiled SQL statement" or simply as a "statement".
2513**
2514** The life of a statement object goes something like this:
2515**
2516** <ol>
2517** <li> Create the object using [sqlite3_prepare_v2()] or a related
2518**      function.
2519** <li> Bind values to [host parameters] using the sqlite3_bind_*()
2520**      interfaces.
2521** <li> Run the SQL by calling [sqlite3_step()] one or more times.
2522** <li> Reset the statement using [sqlite3_reset()] then go back
2523**      to step 2.  Do this zero or more times.
2524** <li> Destroy the object using [sqlite3_finalize()].
2525** </ol>
2526**
2527** Refer to documentation on individual methods above for additional
2528** information.
2529*/
2530typedef struct sqlite3_stmt sqlite3_stmt;
2531
2532/*
2533** CAPI3REF: Run-time Limits {H12760} <S20600>
2534**
2535** This interface allows the size of various constructs to be limited
2536** on a connection by connection basis.  The first parameter is the
2537** [database connection] whose limit is to be set or queried.  The
2538** second parameter is one of the [limit categories] that define a
2539** class of constructs to be size limited.  The third parameter is the
2540** new limit for that construct.  The function returns the old limit.
2541**
2542** If the new limit is a negative number, the limit is unchanged.
2543** For the limit category of SQLITE_LIMIT_XYZ there is a hard upper
2544** bound set by a compile-time C preprocessor macro named SQLITE_MAX_XYZ.
2545** (The "_LIMIT_" in the name is changed to "_MAX_".)
2546** Attempts to increase a limit above its hard upper bound are
2547** silently truncated to the hard upper limit.
2548**
2549** Run time limits are intended for use in applications that manage
2550** both their own internal database and also databases that are controlled
2551** by untrusted external sources.  An example application might be a
2552** webbrowser that has its own databases for storing history and
2553** separate databases controlled by JavaScript applications downloaded
2554** off the Internet.  The internal databases can be given the
2555** large, default limits.  Databases managed by external sources can
2556** be given much smaller limits designed to prevent a denial of service
2557** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
2558** interface to further control untrusted SQL.  The size of the database
2559** created by an untrusted script can be contained using the
2560** [max_page_count] [PRAGMA].
2561**
2562** New run-time limit categories may be added in future releases.
2563**
2564** INVARIANTS:
2565**
2566** {H12762} A successful call to [sqlite3_limit(D,C,V)] where V is
2567**          positive changes the limit on the size of construct C in the
2568**          [database connection] D to the lesser of V and the hard upper
2569**          bound on the size of C that is set at compile-time.
2570**
2571** {H12766} A successful call to [sqlite3_limit(D,C,V)] where V is negative
2572**          leaves the state of the [database connection] D unchanged.
2573**
2574** {H12769} A successful call to [sqlite3_limit(D,C,V)] returns the
2575**          value of the limit on the size of construct C in the
2576**          [database connection] D as it was prior to the call.
2577*/
2578int sqlite3_limit(sqlite3*, int id, int newVal);
2579
2580/*
2581** CAPI3REF: Run-Time Limit Categories {H12790} <H12760>
2582** KEYWORDS: {limit category} {limit categories}
2583**
2584** These constants define various aspects of a [database connection]
2585** that can be limited in size by calls to [sqlite3_limit()].
2586** The meanings of the various limits are as follows:
2587**
2588** <dl>
2589** <dt>SQLITE_LIMIT_LENGTH</dt>
2590** <dd>The maximum size of any string or BLOB or table row.<dd>
2591**
2592** <dt>SQLITE_LIMIT_SQL_LENGTH</dt>
2593** <dd>The maximum length of an SQL statement.</dd>
2594**
2595** <dt>SQLITE_LIMIT_COLUMN</dt>
2596** <dd>The maximum number of columns in a table definition or in the
2597** result set of a SELECT or the maximum number of columns in an index
2598** or in an ORDER BY or GROUP BY clause.</dd>
2599**
2600** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
2601** <dd>The maximum depth of the parse tree on any expression.</dd>
2602**
2603** <dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
2604** <dd>The maximum number of terms in a compound SELECT statement.</dd>
2605**
2606** <dt>SQLITE_LIMIT_VDBE_OP</dt>
2607** <dd>The maximum number of instructions in a virtual machine program
2608** used to implement an SQL statement.</dd>
2609**
2610** <dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
2611** <dd>The maximum number of arguments on a function.</dd>
2612**
2613** <dt>SQLITE_LIMIT_ATTACHED</dt>
2614** <dd>The maximum number of attached databases.</dd>
2615**
2616** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
2617** <dd>The maximum length of the pattern argument to the LIKE or
2618** GLOB operators.</dd>
2619**
2620** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
2621** <dd>The maximum number of variables in an SQL statement that can
2622** be bound.</dd>
2623** </dl>
2624*/
2625#define SQLITE_LIMIT_LENGTH                    0
2626#define SQLITE_LIMIT_SQL_LENGTH                1
2627#define SQLITE_LIMIT_COLUMN                    2
2628#define SQLITE_LIMIT_EXPR_DEPTH                3
2629#define SQLITE_LIMIT_COMPOUND_SELECT           4
2630#define SQLITE_LIMIT_VDBE_OP                   5
2631#define SQLITE_LIMIT_FUNCTION_ARG              6
2632#define SQLITE_LIMIT_ATTACHED                  7
2633#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
2634#define SQLITE_LIMIT_VARIABLE_NUMBER           9
2635
2636/*
2637** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
2638** KEYWORDS: {SQL statement compiler}
2639**
2640** To execute an SQL query, it must first be compiled into a byte-code
2641** program using one of these routines.
2642**
2643** The first argument, "db", is a [database connection] obtained from a
2644** prior call to [sqlite3_open()], [sqlite3_open_v2()] or [sqlite3_open16()].
2645**
2646** The second argument, "zSql", is the statement to be compiled, encoded
2647** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
2648** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
2649** use UTF-16.
2650**
2651** If the nByte argument is less than zero, then zSql is read up to the
2652** first zero terminator. If nByte is non-negative, then it is the maximum
2653** number of  bytes read from zSql.  When nByte is non-negative, the
2654** zSql string ends at either the first '\000' or '\u0000' character or
2655** the nByte-th byte, whichever comes first. If the caller knows
2656** that the supplied string is nul-terminated, then there is a small
2657** performance advantage to be gained by passing an nByte parameter that
2658** is equal to the number of bytes in the input string <i>including</i>
2659** the nul-terminator bytes.
2660**
2661** *pzTail is made to point to the first byte past the end of the
2662** first SQL statement in zSql.  These routines only compile the first
2663** statement in zSql, so *pzTail is left pointing to what remains
2664** uncompiled.
2665**
2666** *ppStmt is left pointing to a compiled [prepared statement] that can be
2667** executed using [sqlite3_step()].  If there is an error, *ppStmt is set
2668** to NULL.  If the input text contains no SQL (if the input is an empty
2669** string or a comment) then *ppStmt is set to NULL.
2670** {A13018} The calling procedure is responsible for deleting the compiled
2671** SQL statement using [sqlite3_finalize()] after it has finished with it.
2672**
2673** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
2674**
2675** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
2676** recommended for all new programs. The two older interfaces are retained
2677** for backwards compatibility, but their use is discouraged.
2678** In the "v2" interfaces, the prepared statement
2679** that is returned (the [sqlite3_stmt] object) contains a copy of the
2680** original SQL text. This causes the [sqlite3_step()] interface to
2681** behave a differently in two ways:
2682**
2683** <ol>
2684** <li>
2685** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
2686** always used to do, [sqlite3_step()] will automatically recompile the SQL
2687** statement and try to run it again.  If the schema has changed in
2688** a way that makes the statement no longer valid, [sqlite3_step()] will still
2689** return [SQLITE_SCHEMA].  But unlike the legacy behavior, [SQLITE_SCHEMA] is
2690** now a fatal error.  Calling [sqlite3_prepare_v2()] again will not make the
2691** error go away.  Note: use [sqlite3_errmsg()] to find the text
2692** of the parsing error that results in an [SQLITE_SCHEMA] return.
2693** </li>
2694**
2695** <li>
2696** When an error occurs, [sqlite3_step()] will return one of the detailed
2697** [error codes] or [extended error codes].  The legacy behavior was that
2698** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
2699** and you would have to make a second call to [sqlite3_reset()] in order
2700** to find the underlying cause of the problem. With the "v2" prepare
2701** interfaces, the underlying reason for the error is returned immediately.
2702** </li>
2703** </ol>
2704**
2705** INVARIANTS:
2706**
2707** {H13011} The [sqlite3_prepare(db,zSql,...)] and
2708**          [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the
2709**          text in their zSql parameter as UTF-8.
2710**
2711** {H13012} The [sqlite3_prepare16(db,zSql,...)] and
2712**          [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the
2713**          text in their zSql parameter as UTF-16 in the native byte order.
2714**
2715** {H13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
2716**          and its variants is less than zero, the SQL text is
2717**          read from zSql is read up to the first zero terminator.
2718**
2719** {H13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
2720**          and its variants is non-negative, then at most nBytes bytes of
2721**          SQL text is read from zSql.
2722**
2723** {H13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants
2724**          if the zSql input text contains more than one SQL statement
2725**          and pzTail is not NULL, then *pzTail is made to point to the
2726**          first byte past the end of the first SQL statement in zSql.
2727**          <todo>What does *pzTail point to if there is one statement?</todo>
2728**
2729** {H13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)]
2730**          or one of its variants writes into *ppStmt a pointer to a new
2731**          [prepared statement] or a pointer to NULL if zSql contains
2732**          nothing other than whitespace or comments.
2733**
2734** {H13019} The [sqlite3_prepare_v2()] interface and its variants return
2735**          [SQLITE_OK] or an appropriate [error code] upon failure.
2736**
2737** {H13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its
2738**          variants returns an error (any value other than [SQLITE_OK]),
2739**          they first set *ppStmt to NULL.
2740*/
2741int sqlite3_prepare(
2742  sqlite3 *db,            /* Database handle */
2743  const char *zSql,       /* SQL statement, UTF-8 encoded */
2744  int nByte,              /* Maximum length of zSql in bytes. */
2745  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
2746  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
2747);
2748int sqlite3_prepare_v2(
2749  sqlite3 *db,            /* Database handle */
2750  const char *zSql,       /* SQL statement, UTF-8 encoded */
2751  int nByte,              /* Maximum length of zSql in bytes. */
2752  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
2753  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
2754);
2755int sqlite3_prepare16(
2756  sqlite3 *db,            /* Database handle */
2757  const void *zSql,       /* SQL statement, UTF-16 encoded */
2758  int nByte,              /* Maximum length of zSql in bytes. */
2759  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
2760  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
2761);
2762int sqlite3_prepare16_v2(
2763  sqlite3 *db,            /* Database handle */
2764  const void *zSql,       /* SQL statement, UTF-16 encoded */
2765  int nByte,              /* Maximum length of zSql in bytes. */
2766  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
2767  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
2768);
2769
2770/*
2771** CAPIREF: Retrieving Statement SQL {H13100} <H13000>
2772**
2773** This interface can be used to retrieve a saved copy of the original
2774** SQL text used to create a [prepared statement] if that statement was
2775** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
2776**
2777** INVARIANTS:
2778**
2779** {H13101} If the [prepared statement] passed as the argument to
2780**          [sqlite3_sql()] was compiled using either [sqlite3_prepare_v2()] or
2781**          [sqlite3_prepare16_v2()], then [sqlite3_sql()] returns
2782**          a pointer to a zero-terminated string containing a UTF-8 rendering
2783**          of the original SQL statement.
2784**
2785** {H13102} If the [prepared statement] passed as the argument to
2786**          [sqlite3_sql()] was compiled using either [sqlite3_prepare()] or
2787**          [sqlite3_prepare16()], then [sqlite3_sql()] returns a NULL pointer.
2788**
2789** {H13103} The string returned by [sqlite3_sql(S)] is valid until the
2790**          [prepared statement] S is deleted using [sqlite3_finalize(S)].
2791*/
2792const char *sqlite3_sql(sqlite3_stmt *pStmt);
2793
2794/*
2795** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200>
2796** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
2797**
2798** SQLite uses the sqlite3_value object to represent all values
2799** that can be stored in a database table. SQLite uses dynamic typing
2800** for the values it stores. Values stored in sqlite3_value objects
2801** can be integers, floating point values, strings, BLOBs, or NULL.
2802**
2803** An sqlite3_value object may be either "protected" or "unprotected".
2804** Some interfaces require a protected sqlite3_value.  Other interfaces
2805** will accept either a protected or an unprotected sqlite3_value.
2806** Every interface that accepts sqlite3_value arguments specifies
2807** whether or not it requires a protected sqlite3_value.
2808**
2809** The terms "protected" and "unprotected" refer to whether or not
2810** a mutex is held.  A internal mutex is held for a protected
2811** sqlite3_value object but no mutex is held for an unprotected
2812** sqlite3_value object.  If SQLite is compiled to be single-threaded
2813** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
2814** or if SQLite is run in one of reduced mutex modes
2815** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
2816** then there is no distinction between protected and unprotected
2817** sqlite3_value objects and they can be used interchangeably.  However,
2818** for maximum code portability it is recommended that applications
2819** still make the distinction between between protected and unprotected
2820** sqlite3_value objects even when not strictly required.
2821**
2822** The sqlite3_value objects that are passed as parameters into the
2823** implementation of [application-defined SQL functions] are protected.
2824** The sqlite3_value object returned by
2825** [sqlite3_column_value()] is unprotected.
2826** Unprotected sqlite3_value objects may only be used with
2827** [sqlite3_result_value()] and [sqlite3_bind_value()].
2828** The [sqlite3_value_blob | sqlite3_value_type()] family of
2829** interfaces require protected sqlite3_value objects.
2830*/
2831typedef struct Mem sqlite3_value;
2832
2833/*
2834** CAPI3REF: SQL Function Context Object {H16001} <S20200>
2835**
2836** The context in which an SQL function executes is stored in an
2837** sqlite3_context object.  A pointer to an sqlite3_context object
2838** is always first parameter to [application-defined SQL functions].
2839** The application-defined SQL function implementation will pass this
2840** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
2841** [sqlite3_aggregate_context()], [sqlite3_user_data()],
2842** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
2843** and/or [sqlite3_set_auxdata()].
2844*/
2845typedef struct sqlite3_context sqlite3_context;
2846
2847/*
2848** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300>
2849** KEYWORDS: {host parameter} {host parameters} {host parameter name}
2850** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
2851**
2852** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
2853** literals may be replaced by a parameter in one of these forms:
2854**
2855** <ul>
2856** <li>  ?
2857** <li>  ?NNN
2858** <li>  :VVV
2859** <li>  @VVV
2860** <li>  $VVV
2861** </ul>
2862**
2863** In the parameter forms shown above NNN is an integer literal,
2864** and VVV is an alpha-numeric parameter name. The values of these
2865** parameters (also called "host parameter names" or "SQL parameters")
2866** can be set using the sqlite3_bind_*() routines defined here.
2867**
2868** The first argument to the sqlite3_bind_*() routines is always
2869** a pointer to the [sqlite3_stmt] object returned from
2870** [sqlite3_prepare_v2()] or its variants.
2871**
2872** The second argument is the index of the SQL parameter to be set.
2873** The leftmost SQL parameter has an index of 1.  When the same named
2874** SQL parameter is used more than once, second and subsequent
2875** occurrences have the same index as the first occurrence.
2876** The index for named parameters can be looked up using the
2877** [sqlite3_bind_parameter_index()] API if desired.  The index
2878** for "?NNN" parameters is the value of NNN.
2879** The NNN value must be between 1 and the [sqlite3_limit()]
2880** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
2881**
2882** The third argument is the value to bind to the parameter.
2883**
2884** In those routines that have a fourth argument, its value is the
2885** number of bytes in the parameter.  To be clear: the value is the
2886** number of <u>bytes</u> in the value, not the number of characters.
2887** If the fourth parameter is negative, the length of the string is
2888** the number of bytes up to the first zero terminator.
2889**
2890** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
2891** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
2892** string after SQLite has finished with it. If the fifth argument is
2893** the special value [SQLITE_STATIC], then SQLite assumes that the
2894** information is in static, unmanaged space and does not need to be freed.
2895** If the fifth argument has the value [SQLITE_TRANSIENT], then
2896** SQLite makes its own private copy of the data immediately, before
2897** the sqlite3_bind_*() routine returns.
2898**
2899** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
2900** is filled with zeroes.  A zeroblob uses a fixed amount of memory
2901** (just an integer to hold its size) while it is being processed.
2902** Zeroblobs are intended to serve as placeholders for BLOBs whose
2903** content is later written using
2904** [sqlite3_blob_open | incremental BLOB I/O] routines.
2905** A negative value for the zeroblob results in a zero-length BLOB.
2906**
2907** The sqlite3_bind_*() routines must be called after
2908** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
2909** before [sqlite3_step()].
2910** Bindings are not cleared by the [sqlite3_reset()] routine.
2911** Unbound parameters are interpreted as NULL.
2912**
2913** These routines return [SQLITE_OK] on success or an error code if
2914** anything goes wrong.  [SQLITE_RANGE] is returned if the parameter
2915** index is out of range.  [SQLITE_NOMEM] is returned if malloc() fails.
2916** [SQLITE_MISUSE] might be returned if these routines are called on a
2917** virtual machine that is the wrong state or which has already been finalized.
2918** Detection of misuse is unreliable.  Applications should not depend
2919** on SQLITE_MISUSE returns.  SQLITE_MISUSE is intended to indicate a
2920** a logic error in the application.  Future versions of SQLite might
2921** panic rather than return SQLITE_MISUSE.
2922**
2923** See also: [sqlite3_bind_parameter_count()],
2924** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
2925**
2926** INVARIANTS:
2927**
2928** {H13506} The [SQL statement compiler] recognizes tokens of the forms
2929**          "?", "?NNN", "$VVV", ":VVV", and "@VVV" as SQL parameters,
2930**          where NNN is any sequence of one or more digits
2931**          and where VVV is any sequence of one or more alphanumeric
2932**          characters or "::" optionally followed by a string containing
2933**          no spaces and contained within parentheses.
2934**
2935** {H13509} The initial value of an SQL parameter is NULL.
2936**
2937** {H13512} The index of an "?" SQL parameter is one larger than the
2938**          largest index of SQL parameter to the left, or 1 if
2939**          the "?" is the leftmost SQL parameter.
2940**
2941** {H13515} The index of an "?NNN" SQL parameter is the integer NNN.
2942**
2943** {H13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is
2944**          the same as the index of leftmost occurrences of the same
2945**          parameter, or one more than the largest index over all
2946**          parameters to the left if this is the first occurrence
2947**          of this parameter, or 1 if this is the leftmost parameter.
2948**
2949** {H13521} The [SQL statement compiler] fails with an [SQLITE_RANGE]
2950**          error if the index of an SQL parameter is less than 1
2951**          or greater than the compile-time SQLITE_MAX_VARIABLE_NUMBER
2952**          parameter.
2953**
2954** {H13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)]
2955**          associate the value V with all SQL parameters having an
2956**          index of N in the [prepared statement] S.
2957**
2958** {H13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)]
2959**          override prior calls with the same values of S and N.
2960**
2961** {H13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)]
2962**          persist across calls to [sqlite3_reset(S)].
2963**
2964** {H13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
2965**          [sqlite3_bind_text(S,N,V,L,D)], or
2966**          [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L
2967**          bytes of the BLOB or string pointed to by V, when L
2968**          is non-negative.
2969**
2970** {H13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or
2971**          [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters
2972**          from V through the first zero character when L is negative.
2973**
2974** {H13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
2975**          [sqlite3_bind_text(S,N,V,L,D)], or
2976**          [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
2977**          constant [SQLITE_STATIC], SQLite assumes that the value V
2978**          is held in static unmanaged space that will not change
2979**          during the lifetime of the binding.
2980**
2981** {H13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
2982**          [sqlite3_bind_text(S,N,V,L,D)], or
2983**          [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
2984**          constant [SQLITE_TRANSIENT], the routine makes a
2985**          private copy of the value V before it returns.
2986**
2987** {H13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
2988**          [sqlite3_bind_text(S,N,V,L,D)], or
2989**          [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to
2990**          a function, SQLite invokes that function to destroy the
2991**          value V after it has finished using the value V.
2992**
2993** {H13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound
2994**          is a BLOB of L bytes, or a zero-length BLOB if L is negative.
2995**
2996** {H13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may
2997**          be either a [protected sqlite3_value] object or an
2998**          [unprotected sqlite3_value] object.
2999*/
3000int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
3001int sqlite3_bind_double(sqlite3_stmt*, int, double);
3002int sqlite3_bind_int(sqlite3_stmt*, int, int);
3003int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
3004int sqlite3_bind_null(sqlite3_stmt*, int);
3005int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
3006int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
3007int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
3008int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
3009
3010/*
3011** CAPI3REF: Number Of SQL Parameters {H13600} <S70300>
3012**
3013** This routine can be used to find the number of [SQL parameters]
3014** in a [prepared statement].  SQL parameters are tokens of the
3015** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
3016** placeholders for values that are [sqlite3_bind_blob | bound]
3017** to the parameters at a later time.
3018**
3019** This routine actually returns the index of the largest (rightmost)
3020** parameter. For all forms except ?NNN, this will correspond to the
3021** number of unique parameters.  If parameters of the ?NNN are used,
3022** there may be gaps in the list.
3023**
3024** See also: [sqlite3_bind_blob|sqlite3_bind()],
3025** [sqlite3_bind_parameter_name()], and
3026** [sqlite3_bind_parameter_index()].
3027**
3028** INVARIANTS:
3029**
3030** {H13601} The [sqlite3_bind_parameter_count(S)] interface returns
3031**          the largest index of all SQL parameters in the
3032**          [prepared statement] S, or 0 if S contains no SQL parameters.
3033*/
3034int sqlite3_bind_parameter_count(sqlite3_stmt*);
3035
3036/*
3037** CAPI3REF: Name Of A Host Parameter {H13620} <S70300>
3038**
3039** This routine returns a pointer to the name of the n-th
3040** [SQL parameter] in a [prepared statement].
3041** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
3042** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
3043** respectively.
3044** In other words, the initial ":" or "$" or "@" or "?"
3045** is included as part of the name.
3046** Parameters of the form "?" without a following integer have no name
3047** and are also referred to as "anonymous parameters".
3048**
3049** The first host parameter has an index of 1, not 0.
3050**
3051** If the value n is out of range or if the n-th parameter is
3052** nameless, then NULL is returned.  The returned string is
3053** always in UTF-8 encoding even if the named parameter was
3054** originally specified as UTF-16 in [sqlite3_prepare16()] or
3055** [sqlite3_prepare16_v2()].
3056**
3057** See also: [sqlite3_bind_blob|sqlite3_bind()],
3058** [sqlite3_bind_parameter_count()], and
3059** [sqlite3_bind_parameter_index()].
3060**
3061** INVARIANTS:
3062**
3063** {H13621} The [sqlite3_bind_parameter_name(S,N)] interface returns
3064**          a UTF-8 rendering of the name of the SQL parameter in
3065**          the [prepared statement] S having index N, or
3066**          NULL if there is no SQL parameter with index N or if the
3067**          parameter with index N is an anonymous parameter "?".
3068*/
3069const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
3070
3071/*
3072** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300>
3073**
3074** Return the index of an SQL parameter given its name.  The
3075** index value returned is suitable for use as the second
3076** parameter to [sqlite3_bind_blob|sqlite3_bind()].  A zero
3077** is returned if no matching parameter is found.  The parameter
3078** name must be given in UTF-8 even if the original statement
3079** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
3080**
3081** See also: [sqlite3_bind_blob|sqlite3_bind()],
3082** [sqlite3_bind_parameter_count()], and
3083** [sqlite3_bind_parameter_index()].
3084**
3085** INVARIANTS:
3086**
3087** {H13641} The [sqlite3_bind_parameter_index(S,N)] interface returns
3088**          the index of SQL parameter in the [prepared statement]
3089**          S whose name matches the UTF-8 string N, or 0 if there is
3090**          no match.
3091*/
3092int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
3093
3094/*
3095** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300>
3096**
3097** Contrary to the intuition of many, [sqlite3_reset()] does not reset
3098** the [sqlite3_bind_blob | bindings] on a [prepared statement].
3099** Use this routine to reset all host parameters to NULL.
3100**
3101** INVARIANTS:
3102**
3103** {H13661} The [sqlite3_clear_bindings(S)] interface resets all SQL
3104**          parameter bindings in the [prepared statement] S back to NULL.
3105*/
3106int sqlite3_clear_bindings(sqlite3_stmt*);
3107
3108/*
3109** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700>
3110**
3111** Return the number of columns in the result set returned by the
3112** [prepared statement]. This routine returns 0 if pStmt is an SQL
3113** statement that does not return data (for example an [UPDATE]).
3114**
3115** INVARIANTS:
3116**
3117** {H13711} The [sqlite3_column_count(S)] interface returns the number of
3118**          columns in the result set generated by the [prepared statement] S,
3119**          or 0 if S does not generate a result set.
3120*/
3121int sqlite3_column_count(sqlite3_stmt *pStmt);
3122
3123/*
3124** CAPI3REF: Column Names In A Result Set {H13720} <S10700>
3125**
3126** These routines return the name assigned to a particular column
3127** in the result set of a [SELECT] statement.  The sqlite3_column_name()
3128** interface returns a pointer to a zero-terminated UTF-8 string
3129** and sqlite3_column_name16() returns a pointer to a zero-terminated
3130** UTF-16 string.  The first parameter is the [prepared statement]
3131** that implements the [SELECT] statement. The second parameter is the
3132** column number.  The leftmost column is number 0.
3133**
3134** The returned string pointer is valid until either the [prepared statement]
3135** is destroyed by [sqlite3_finalize()] or until the next call to
3136** sqlite3_column_name() or sqlite3_column_name16() on the same column.
3137**
3138** If sqlite3_malloc() fails during the processing of either routine
3139** (for example during a conversion from UTF-8 to UTF-16) then a
3140** NULL pointer is returned.
3141**
3142** The name of a result column is the value of the "AS" clause for
3143** that column, if there is an AS clause.  If there is no AS clause
3144** then the name of the column is unspecified and may change from
3145** one release of SQLite to the next.
3146**
3147** INVARIANTS:
3148**
3149** {H13721} A successful invocation of the [sqlite3_column_name(S,N)]
3150**          interface returns the name of the Nth column (where 0 is
3151**          the leftmost column) for the result set of the
3152**          [prepared statement] S as a zero-terminated UTF-8 string.
3153**
3154** {H13723} A successful invocation of the [sqlite3_column_name16(S,N)]
3155**          interface returns the name of the Nth column (where 0 is
3156**          the leftmost column) for the result set of the
3157**          [prepared statement] S as a zero-terminated UTF-16 string
3158**          in the native byte order.
3159**
3160** {H13724} The [sqlite3_column_name()] and [sqlite3_column_name16()]
3161**          interfaces return a NULL pointer if they are unable to
3162**          allocate memory to hold their normal return strings.
3163**
3164** {H13725} If the N parameter to [sqlite3_column_name(S,N)] or
3165**          [sqlite3_column_name16(S,N)] is out of range, then the
3166**          interfaces return a NULL pointer.
3167**
3168** {H13726} The strings returned by [sqlite3_column_name(S,N)] and
3169**          [sqlite3_column_name16(S,N)] are valid until the next
3170**          call to either routine with the same S and N parameters
3171**          or until [sqlite3_finalize(S)] is called.
3172**
3173** {H13727} When a result column of a [SELECT] statement contains
3174**          an AS clause, the name of that column is the identifier
3175**          to the right of the AS keyword.
3176*/
3177const char *sqlite3_column_name(sqlite3_stmt*, int N);
3178const void *sqlite3_column_name16(sqlite3_stmt*, int N);
3179
3180/*
3181** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700>
3182**
3183** These routines provide a means to determine what column of what
3184** table in which database a result of a [SELECT] statement comes from.
3185** The name of the database or table or column can be returned as
3186** either a UTF-8 or UTF-16 string.  The _database_ routines return
3187** the database name, the _table_ routines return the table name, and
3188** the origin_ routines return the column name.
3189** The returned string is valid until the [prepared statement] is destroyed
3190** using [sqlite3_finalize()] or until the same information is requested
3191** again in a different encoding.
3192**
3193** The names returned are the original un-aliased names of the
3194** database, table, and column.
3195**
3196** The first argument to the following calls is a [prepared statement].
3197** These functions return information about the Nth column returned by
3198** the statement, where N is the second function argument.
3199**
3200** If the Nth column returned by the statement is an expression or
3201** subquery and is not a column value, then all of these functions return
3202** NULL.  These routine might also return NULL if a memory allocation error
3203** occurs.  Otherwise, they return the name of the attached database, table
3204** and column that query result column was extracted from.
3205**
3206** As with all other SQLite APIs, those postfixed with "16" return
3207** UTF-16 encoded strings, the other functions return UTF-8. {END}
3208**
3209** These APIs are only available if the library was compiled with the
3210** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
3211**
3212** {A13751}
3213** If two or more threads call one or more of these routines against the same
3214** prepared statement and column at the same time then the results are
3215** undefined.
3216**
3217** INVARIANTS:
3218**
3219** {H13741} The [sqlite3_column_database_name(S,N)] interface returns either
3220**          the UTF-8 zero-terminated name of the database from which the
3221**          Nth result column of the [prepared statement] S is extracted,
3222**          or NULL if the Nth column of S is a general expression
3223**          or if unable to allocate memory to store the name.
3224**
3225** {H13742} The [sqlite3_column_database_name16(S,N)] interface returns either
3226**          the UTF-16 native byte order zero-terminated name of the database
3227**          from which the Nth result column of the [prepared statement] S is
3228**          extracted, or NULL if the Nth column of S is a general expression
3229**          or if unable to allocate memory to store the name.
3230**
3231** {H13743} The [sqlite3_column_table_name(S,N)] interface returns either
3232**          the UTF-8 zero-terminated name of the table from which the
3233**          Nth result column of the [prepared statement] S is extracted,
3234**          or NULL if the Nth column of S is a general expression
3235**          or if unable to allocate memory to store the name.
3236**
3237** {H13744} The [sqlite3_column_table_name16(S,N)] interface returns either
3238**          the UTF-16 native byte order zero-terminated name of the table
3239**          from which the Nth result column of the [prepared statement] S is
3240**          extracted, or NULL if the Nth column of S is a general expression
3241**          or if unable to allocate memory to store the name.
3242**
3243** {H13745} The [sqlite3_column_origin_name(S,N)] interface returns either
3244**          the UTF-8 zero-terminated name of the table column from which the
3245**          Nth result column of the [prepared statement] S is extracted,
3246**          or NULL if the Nth column of S is a general expression
3247**          or if unable to allocate memory to store the name.
3248**
3249** {H13746} The [sqlite3_column_origin_name16(S,N)] interface returns either
3250**          the UTF-16 native byte order zero-terminated name of the table
3251**          column from which the Nth result column of the
3252**          [prepared statement] S is extracted, or NULL if the Nth column
3253**          of S is a general expression or if unable to allocate memory
3254**          to store the name.
3255**
3256** {H13748} The return values from
3257**          [sqlite3_column_database_name | column metadata interfaces]
3258**          are valid for the lifetime of the [prepared statement]
3259**          or until the encoding is changed by another metadata
3260**          interface call for the same prepared statement and column.
3261**
3262** ASSUMPTIONS:
3263**
3264** {A13751} If two or more threads call one or more
3265**          [sqlite3_column_database_name | column metadata interfaces]
3266**          for the same [prepared statement] and result column
3267**          at the same time then the results are undefined.
3268*/
3269const char *sqlite3_column_database_name(sqlite3_stmt*,int);
3270const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
3271const char *sqlite3_column_table_name(sqlite3_stmt*,int);
3272const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
3273const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
3274const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
3275
3276/*
3277** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700>
3278**
3279** The first parameter is a [prepared statement].
3280** If this statement is a [SELECT] statement and the Nth column of the
3281** returned result set of that [SELECT] is a table column (not an
3282** expression or subquery) then the declared type of the table
3283** column is returned.  If the Nth column of the result set is an
3284** expression or subquery, then a NULL pointer is returned.
3285** The returned string is always UTF-8 encoded. {END}
3286**
3287** For example, given the database schema:
3288**
3289** CREATE TABLE t1(c1 VARIANT);
3290**
3291** and the following statement to be compiled:
3292**
3293** SELECT c1 + 1, c1 FROM t1;
3294**
3295** this routine would return the string "VARIANT" for the second result
3296** column (i==1), and a NULL pointer for the first result column (i==0).
3297**
3298** SQLite uses dynamic run-time typing.  So just because a column
3299** is declared to contain a particular type does not mean that the
3300** data stored in that column is of the declared type.  SQLite is
3301** strongly typed, but the typing is dynamic not static.  Type
3302** is associated with individual values, not with the containers
3303** used to hold those values.
3304**
3305** INVARIANTS:
3306**
3307** {H13761}  A successful call to [sqlite3_column_decltype(S,N)] returns a
3308**           zero-terminated UTF-8 string containing the declared datatype
3309**           of the table column that appears as the Nth column (numbered
3310**           from 0) of the result set to the [prepared statement] S.
3311**
3312** {H13762}  A successful call to [sqlite3_column_decltype16(S,N)]
3313**           returns a zero-terminated UTF-16 native byte order string
3314**           containing the declared datatype of the table column that appears
3315**           as the Nth column (numbered from 0) of the result set to the
3316**           [prepared statement] S.
3317**
3318** {H13763}  If N is less than 0 or N is greater than or equal to
3319**           the number of columns in the [prepared statement] S,
3320**           or if the Nth column of S is an expression or subquery rather
3321**           than a table column, or if a memory allocation failure
3322**           occurs during encoding conversions, then
3323**           calls to [sqlite3_column_decltype(S,N)] or
3324**           [sqlite3_column_decltype16(S,N)] return NULL.
3325*/
3326const char *sqlite3_column_decltype(sqlite3_stmt*,int);
3327const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
3328
3329/*
3330** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000>
3331**
3332** After a [prepared statement] has been prepared using either
3333** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
3334** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
3335** must be called one or more times to evaluate the statement.
3336**
3337** The details of the behavior of the sqlite3_step() interface depend
3338** on whether the statement was prepared using the newer "v2" interface
3339** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
3340** interface [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
3341** new "v2" interface is recommended for new applications but the legacy
3342** interface will continue to be supported.
3343**
3344** In the legacy interface, the return value will be either [SQLITE_BUSY],
3345** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
3346** With the "v2" interface, any of the other [result codes] or
3347** [extended result codes] might be returned as well.
3348**
3349** [SQLITE_BUSY] means that the database engine was unable to acquire the
3350** database locks it needs to do its job.  If the statement is a [COMMIT]
3351** or occurs outside of an explicit transaction, then you can retry the
3352** statement.  If the statement is not a [COMMIT] and occurs within a
3353** explicit transaction then you should rollback the transaction before
3354** continuing.
3355**
3356** [SQLITE_DONE] means that the statement has finished executing
3357** successfully.  sqlite3_step() should not be called again on this virtual
3358** machine without first calling [sqlite3_reset()] to reset the virtual
3359** machine back to its initial state.
3360**
3361** If the SQL statement being executed returns any data, then [SQLITE_ROW]
3362** is returned each time a new row of data is ready for processing by the
3363** caller. The values may be accessed using the [column access functions].
3364** sqlite3_step() is called again to retrieve the next row of data.
3365**
3366** [SQLITE_ERROR] means that a run-time error (such as a constraint
3367** violation) has occurred.  sqlite3_step() should not be called again on
3368** the VM. More information may be found by calling [sqlite3_errmsg()].
3369** With the legacy interface, a more specific error code (for example,
3370** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
3371** can be obtained by calling [sqlite3_reset()] on the
3372** [prepared statement].  In the "v2" interface,
3373** the more specific error code is returned directly by sqlite3_step().
3374**
3375** [SQLITE_MISUSE] means that the this routine was called inappropriately.
3376** Perhaps it was called on a [prepared statement] that has
3377** already been [sqlite3_finalize | finalized] or on one that had
3378** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
3379** be the case that the same database connection is being used by two or
3380** more threads at the same moment in time.
3381**
3382** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
3383** API always returns a generic error code, [SQLITE_ERROR], following any
3384** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
3385** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
3386** specific [error codes] that better describes the error.
3387** We admit that this is a goofy design.  The problem has been fixed
3388** with the "v2" interface.  If you prepare all of your SQL statements
3389** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
3390** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
3391** then the more specific [error codes] are returned directly
3392** by sqlite3_step().  The use of the "v2" interface is recommended.
3393**
3394** INVARIANTS:
3395**
3396** {H13202}  If the [prepared statement] S is ready to be run, then
3397**           [sqlite3_step(S)] advances that prepared statement until
3398**           completion or until it is ready to return another row of the
3399**           result set, or until an [sqlite3_interrupt | interrupt]
3400**           or a run-time error occurs.
3401**
3402** {H15304}  When a call to [sqlite3_step(S)] causes the [prepared statement]
3403**           S to run to completion, the function returns [SQLITE_DONE].
3404**
3405** {H15306}  When a call to [sqlite3_step(S)] stops because it is ready to
3406**           return another row of the result set, it returns [SQLITE_ROW].
3407**
3408** {H15308}  If a call to [sqlite3_step(S)] encounters an
3409**           [sqlite3_interrupt | interrupt] or a run-time error,
3410**           it returns an appropriate error code that is not one of
3411**           [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE].
3412**
3413** {H15310}  If an [sqlite3_interrupt | interrupt] or a run-time error
3414**           occurs during a call to [sqlite3_step(S)]
3415**           for a [prepared statement] S created using
3416**           legacy interfaces [sqlite3_prepare()] or
3417**           [sqlite3_prepare16()], then the function returns either
3418**           [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE].
3419*/
3420int sqlite3_step(sqlite3_stmt*);
3421
3422/*
3423** CAPI3REF: Number of columns in a result set {H13770} <S10700>
3424**
3425** Returns the number of values in the current row of the result set.
3426**
3427** INVARIANTS:
3428**
3429** {H13771}  After a call to [sqlite3_step(S)] that returns [SQLITE_ROW],
3430**           the [sqlite3_data_count(S)] routine will return the same value
3431**           as the [sqlite3_column_count(S)] function.
3432**
3433** {H13772}  After [sqlite3_step(S)] has returned any value other than
3434**           [SQLITE_ROW] or before [sqlite3_step(S)] has been called on the
3435**           [prepared statement] for the first time since it was
3436**           [sqlite3_prepare | prepared] or [sqlite3_reset | reset],
3437**           the [sqlite3_data_count(S)] routine returns zero.
3438*/
3439int sqlite3_data_count(sqlite3_stmt *pStmt);
3440
3441/*
3442** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120>
3443** KEYWORDS: SQLITE_TEXT
3444**
3445** {H10266} Every value in SQLite has one of five fundamental datatypes:
3446**
3447** <ul>
3448** <li> 64-bit signed integer
3449** <li> 64-bit IEEE floating point number
3450** <li> string
3451** <li> BLOB
3452** <li> NULL
3453** </ul> {END}
3454**
3455** These constants are codes for each of those types.
3456**
3457** Note that the SQLITE_TEXT constant was also used in SQLite version 2
3458** for a completely different meaning.  Software that links against both
3459** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
3460** SQLITE_TEXT.
3461*/
3462#define SQLITE_INTEGER  1
3463#define SQLITE_FLOAT    2
3464#define SQLITE_BLOB     4
3465#define SQLITE_NULL     5
3466#ifdef SQLITE_TEXT
3467# undef SQLITE_TEXT
3468#else
3469# define SQLITE_TEXT     3
3470#endif
3471#define SQLITE3_TEXT     3
3472
3473/*
3474** CAPI3REF: Result Values From A Query {H13800} <S10700>
3475** KEYWORDS: {column access functions}
3476**
3477** These routines form the "result set query" interface.
3478**
3479** These routines return information about a single column of the current
3480** result row of a query.  In every case the first argument is a pointer
3481** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
3482** that was returned from [sqlite3_prepare_v2()] or one of its variants)
3483** and the second argument is the index of the column for which information
3484** should be returned.  The leftmost column of the result set has the index 0.
3485**
3486** If the SQL statement does not currently point to a valid row, or if the
3487** column index is out of range, the result is undefined.
3488** These routines may only be called when the most recent call to
3489** [sqlite3_step()] has returned [SQLITE_ROW] and neither
3490** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
3491** If any of these routines are called after [sqlite3_reset()] or
3492** [sqlite3_finalize()] or after [sqlite3_step()] has returned
3493** something other than [SQLITE_ROW], the results are undefined.
3494** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
3495** are called from a different thread while any of these routines
3496** are pending, then the results are undefined.
3497**
3498** The sqlite3_column_type() routine returns the
3499** [SQLITE_INTEGER | datatype code] for the initial data type
3500** of the result column.  The returned value is one of [SQLITE_INTEGER],
3501** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
3502** returned by sqlite3_column_type() is only meaningful if no type
3503** conversions have occurred as described below.  After a type conversion,
3504** the value returned by sqlite3_column_type() is undefined.  Future
3505** versions of SQLite may change the behavior of sqlite3_column_type()
3506** following a type conversion.
3507**
3508** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
3509** routine returns the number of bytes in that BLOB or string.
3510** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
3511** the string to UTF-8 and then returns the number of bytes.
3512** If the result is a numeric value then sqlite3_column_bytes() uses
3513** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
3514** the number of bytes in that string.
3515** The value returned does not include the zero terminator at the end
3516** of the string.  For clarity: the value returned is the number of
3517** bytes in the string, not the number of characters.
3518**
3519** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
3520** even empty strings, are always zero terminated.  The return
3521** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
3522** pointer, possibly even a NULL pointer.
3523**
3524** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
3525** but leaves the result in UTF-16 in native byte order instead of UTF-8.
3526** The zero terminator is not included in this count.
3527**
3528** The object returned by [sqlite3_column_value()] is an
3529** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
3530** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
3531** If the [unprotected sqlite3_value] object returned by
3532** [sqlite3_column_value()] is used in any other way, including calls
3533** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
3534** or [sqlite3_value_bytes()], then the behavior is undefined.
3535**
3536** These routines attempt to convert the value where appropriate.  For
3537** example, if the internal representation is FLOAT and a text result
3538** is requested, [sqlite3_snprintf()] is used internally to perform the
3539** conversion automatically.  The following table details the conversions
3540** that are applied:
3541**
3542** <blockquote>
3543** <table border="1">
3544** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
3545**
3546** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
3547** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
3548** <tr><td>  NULL    <td>   TEXT    <td> Result is NULL pointer
3549** <tr><td>  NULL    <td>   BLOB    <td> Result is NULL pointer
3550** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
3551** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
3552** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
3553** <tr><td>  FLOAT   <td> INTEGER   <td> Convert from float to integer
3554** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
3555** <tr><td>  FLOAT   <td>   BLOB    <td> Same as FLOAT->TEXT
3556** <tr><td>  TEXT    <td> INTEGER   <td> Use atoi()
3557** <tr><td>  TEXT    <td>  FLOAT    <td> Use atof()
3558** <tr><td>  TEXT    <td>   BLOB    <td> No change
3559** <tr><td>  BLOB    <td> INTEGER   <td> Convert to TEXT then use atoi()
3560** <tr><td>  BLOB    <td>  FLOAT    <td> Convert to TEXT then use atof()
3561** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
3562** </table>
3563** </blockquote>
3564**
3565** The table above makes reference to standard C library functions atoi()
3566** and atof().  SQLite does not really use these functions.  It has its
3567** own equivalent internal routines.  The atoi() and atof() names are
3568** used in the table for brevity and because they are familiar to most
3569** C programmers.
3570**
3571** Note that when type conversions occur, pointers returned by prior
3572** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
3573** sqlite3_column_text16() may be invalidated.
3574** Type conversions and pointer invalidations might occur
3575** in the following cases:
3576**
3577** <ul>
3578** <li> The initial content is a BLOB and sqlite3_column_text() or
3579**      sqlite3_column_text16() is called.  A zero-terminator might
3580**      need to be added to the string.</li>
3581** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
3582**      sqlite3_column_text16() is called.  The content must be converted
3583**      to UTF-16.</li>
3584** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
3585**      sqlite3_column_text() is called.  The content must be converted
3586**      to UTF-8.</li>
3587** </ul>
3588**
3589** Conversions between UTF-16be and UTF-16le are always done in place and do
3590** not invalidate a prior pointer, though of course the content of the buffer
3591** that the prior pointer points to will have been modified.  Other kinds
3592** of conversion are done in place when it is possible, but sometimes they
3593** are not possible and in those cases prior pointers are invalidated.
3594**
3595** The safest and easiest to remember policy is to invoke these routines
3596** in one of the following ways:
3597**
3598** <ul>
3599**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
3600**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
3601**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
3602** </ul>
3603**
3604** In other words, you should call sqlite3_column_text(),
3605** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
3606** into the desired format, then invoke sqlite3_column_bytes() or
3607** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
3608** to sqlite3_column_text() or sqlite3_column_blob() with calls to
3609** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
3610** with calls to sqlite3_column_bytes().
3611**
3612** The pointers returned are valid until a type conversion occurs as
3613** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
3614** [sqlite3_finalize()] is called.  The memory space used to hold strings
3615** and BLOBs is freed automatically.  Do <b>not</b> pass the pointers returned
3616** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
3617** [sqlite3_free()].
3618**
3619** If a memory allocation error occurs during the evaluation of any
3620** of these routines, a default value is returned.  The default value
3621** is either the integer 0, the floating point number 0.0, or a NULL
3622** pointer.  Subsequent calls to [sqlite3_errcode()] will return
3623** [SQLITE_NOMEM].
3624**
3625** INVARIANTS:
3626**
3627** {H13803} The [sqlite3_column_blob(S,N)] interface converts the
3628**          Nth column in the current row of the result set for
3629**          the [prepared statement] S into a BLOB and then returns a
3630**          pointer to the converted value.
3631**
3632** {H13806} The [sqlite3_column_bytes(S,N)] interface returns the
3633**          number of bytes in the BLOB or string (exclusive of the
3634**          zero terminator on the string) that was returned by the
3635**          most recent call to [sqlite3_column_blob(S,N)] or
3636**          [sqlite3_column_text(S,N)].
3637**
3638** {H13809} The [sqlite3_column_bytes16(S,N)] interface returns the
3639**          number of bytes in the string (exclusive of the
3640**          zero terminator on the string) that was returned by the
3641**          most recent call to [sqlite3_column_text16(S,N)].
3642**
3643** {H13812} The [sqlite3_column_double(S,N)] interface converts the
3644**          Nth column in the current row of the result set for the
3645**          [prepared statement] S into a floating point value and
3646**          returns a copy of that value.
3647**
3648** {H13815} The [sqlite3_column_int(S,N)] interface converts the
3649**          Nth column in the current row of the result set for the
3650**          [prepared statement] S into a 64-bit signed integer and
3651**          returns the lower 32 bits of that integer.
3652**
3653** {H13818} The [sqlite3_column_int64(S,N)] interface converts the
3654**          Nth column in the current row of the result set for the
3655**          [prepared statement] S into a 64-bit signed integer and
3656**          returns a copy of that integer.
3657**
3658** {H13821} The [sqlite3_column_text(S,N)] interface converts the
3659**          Nth column in the current row of the result set for
3660**          the [prepared statement] S into a zero-terminated UTF-8
3661**          string and returns a pointer to that string.
3662**
3663** {H13824} The [sqlite3_column_text16(S,N)] interface converts the
3664**          Nth column in the current row of the result set for the
3665**          [prepared statement] S into a zero-terminated 2-byte
3666**          aligned UTF-16 native byte order string and returns
3667**          a pointer to that string.
3668**
3669** {H13827} The [sqlite3_column_type(S,N)] interface returns
3670**          one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
3671**          [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
3672**          the Nth column in the current row of the result set for
3673**          the [prepared statement] S.
3674**
3675** {H13830} The [sqlite3_column_value(S,N)] interface returns a
3676**          pointer to an [unprotected sqlite3_value] object for the
3677**          Nth column in the current row of the result set for
3678**          the [prepared statement] S.
3679*/
3680const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
3681int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
3682int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
3683double sqlite3_column_double(sqlite3_stmt*, int iCol);
3684int sqlite3_column_int(sqlite3_stmt*, int iCol);
3685sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
3686const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
3687const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
3688int sqlite3_column_type(sqlite3_stmt*, int iCol);
3689sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
3690
3691/*
3692** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100>
3693**
3694** The sqlite3_finalize() function is called to delete a [prepared statement].
3695** If the statement was executed successfully or not executed at all, then
3696** SQLITE_OK is returned. If execution of the statement failed then an
3697** [error code] or [extended error code] is returned.
3698**
3699** This routine can be called at any point during the execution of the
3700** [prepared statement].  If the virtual machine has not
3701** completed execution when this routine is called, that is like
3702** encountering an error or an [sqlite3_interrupt | interrupt].
3703** Incomplete updates may be rolled back and transactions canceled,
3704** depending on the circumstances, and the
3705** [error code] returned will be [SQLITE_ABORT].
3706**
3707** INVARIANTS:
3708**
3709** {H11302} The [sqlite3_finalize(S)] interface destroys the
3710**          [prepared statement] S and releases all
3711**          memory and file resources held by that object.
3712**
3713** {H11304} If the most recent call to [sqlite3_step(S)] for the
3714**          [prepared statement] S returned an error,
3715**          then [sqlite3_finalize(S)] returns that same error.
3716*/
3717int sqlite3_finalize(sqlite3_stmt *pStmt);
3718
3719/*
3720** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300>
3721**
3722** The sqlite3_reset() function is called to reset a [prepared statement]
3723** object back to its initial state, ready to be re-executed.
3724** Any SQL statement variables that had values bound to them using
3725** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
3726** Use [sqlite3_clear_bindings()] to reset the bindings.
3727**
3728** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
3729**          back to the beginning of its program.
3730**
3731** {H11334} If the most recent call to [sqlite3_step(S)] for the
3732**          [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
3733**          or if [sqlite3_step(S)] has never before been called on S,
3734**          then [sqlite3_reset(S)] returns [SQLITE_OK].
3735**
3736** {H11336} If the most recent call to [sqlite3_step(S)] for the
3737**          [prepared statement] S indicated an error, then
3738**          [sqlite3_reset(S)] returns an appropriate [error code].
3739**
3740** {H11338} The [sqlite3_reset(S)] interface does not change the values
3741**          of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
3742*/
3743int sqlite3_reset(sqlite3_stmt *pStmt);
3744
3745/*
3746** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200>
3747** KEYWORDS: {function creation routines}
3748** KEYWORDS: {application-defined SQL function}
3749** KEYWORDS: {application-defined SQL functions}
3750**
3751** These two functions (collectively known as "function creation routines")
3752** are used to add SQL functions or aggregates or to redefine the behavior
3753** of existing SQL functions or aggregates.  The only difference between the
3754** two is that the second parameter, the name of the (scalar) function or
3755** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
3756** for sqlite3_create_function16().
3757**
3758** The first parameter is the [database connection] to which the SQL
3759** function is to be added.  If a single program uses more than one database
3760** connection internally, then SQL functions must be added individually to
3761** each database connection.
3762**
3763** The second parameter is the name of the SQL function to be created or
3764** redefined.  The length of the name is limited to 255 bytes, exclusive of
3765** the zero-terminator.  Note that the name length limit is in bytes, not
3766** characters.  Any attempt to create a function with a longer name
3767** will result in [SQLITE_ERROR] being returned.
3768**
3769** The third parameter is the number of arguments that the SQL function or
3770** aggregate takes. If this parameter is negative, then the SQL function or
3771** aggregate may take any number of arguments.
3772**
3773** The fourth parameter, eTextRep, specifies what
3774** [SQLITE_UTF8 | text encoding] this SQL function prefers for
3775** its parameters.  Any SQL function implementation should be able to work
3776** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
3777** more efficient with one encoding than another.  It is allowed to
3778** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
3779** times with the same function but with different values of eTextRep.
3780** When multiple implementations of the same function are available, SQLite
3781** will pick the one that involves the least amount of data conversion.
3782** If there is only a single implementation which does not care what text
3783** encoding is used, then the fourth argument should be [SQLITE_ANY].
3784**
3785** The fifth parameter is an arbitrary pointer.  The implementation of the
3786** function can gain access to this pointer using [sqlite3_user_data()].
3787**
3788** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
3789** pointers to C-language functions that implement the SQL function or
3790** aggregate. A scalar SQL function requires an implementation of the xFunc
3791** callback only, NULL pointers should be passed as the xStep and xFinal
3792** parameters. An aggregate SQL function requires an implementation of xStep
3793** and xFinal and NULL should be passed for xFunc. To delete an existing
3794** SQL function or aggregate, pass NULL for all three function callbacks.
3795**
3796** It is permitted to register multiple implementations of the same
3797** functions with the same name but with either differing numbers of
3798** arguments or differing preferred text encodings.  SQLite will use
3799** the implementation most closely matches the way in which the
3800** SQL function is used.
3801**
3802** INVARIANTS:
3803**
3804** {H16103} The [sqlite3_create_function16()] interface behaves exactly
3805**          like [sqlite3_create_function()] in every way except that it
3806**          interprets the zFunctionName argument as zero-terminated UTF-16
3807**          native byte order instead of as zero-terminated UTF-8.
3808**
3809** {H16106} A successful invocation of
3810**          the [sqlite3_create_function(D,X,N,E,...)] interface registers
3811**          or replaces callback functions in the [database connection] D
3812**          used to implement the SQL function named X with N parameters
3813**          and having a preferred text encoding of E.
3814**
3815** {H16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)]
3816**          replaces the P, F, S, and L values from any prior calls with
3817**          the same D, X, N, and E values.
3818**
3819** {H16112} The [sqlite3_create_function(D,X,...)] interface fails with
3820**          a return code of [SQLITE_ERROR] if the SQL function name X is
3821**          longer than 255 bytes exclusive of the zero terminator.
3822**
3823** {H16118} Either F must be NULL and S and L are non-NULL or else F
3824**          is non-NULL and S and L are NULL, otherwise
3825**          [sqlite3_create_function(D,X,N,E,P,F,S,L)] returns [SQLITE_ERROR].
3826**
3827** {H16121} The [sqlite3_create_function(D,...)] interface fails with an
3828**          error code of [SQLITE_BUSY] if there exist [prepared statements]
3829**          associated with the [database connection] D.
3830**
3831** {H16124} The [sqlite3_create_function(D,X,N,...)] interface fails with an
3832**          error code of [SQLITE_ERROR] if parameter N (specifying the number
3833**          of arguments to the SQL function being registered) is less
3834**          than -1 or greater than 127.
3835**
3836** {H16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)]
3837**          interface causes callbacks to be invoked for the SQL function
3838**          named X when the number of arguments to the SQL function is
3839**          exactly N.
3840**
3841** {H16130} When N is -1, the [sqlite3_create_function(D,X,N,...)]
3842**          interface causes callbacks to be invoked for the SQL function
3843**          named X with any number of arguments.
3844**
3845** {H16133} When calls to [sqlite3_create_function(D,X,N,...)]
3846**          specify multiple implementations of the same function X
3847**          and when one implementation has N>=0 and the other has N=(-1)
3848**          the implementation with a non-zero N is preferred.
3849**
3850** {H16136} When calls to [sqlite3_create_function(D,X,N,E,...)]
3851**          specify multiple implementations of the same function X with
3852**          the same number of arguments N but with different
3853**          encodings E, then the implementation where E matches the
3854**          database encoding is preferred.
3855**
3856** {H16139} For an aggregate SQL function created using
3857**          [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finalizer
3858**          function L will always be invoked exactly once if the
3859**          step function S is called one or more times.
3860**
3861** {H16142} When SQLite invokes either the xFunc or xStep function of
3862**          an application-defined SQL function or aggregate created
3863**          by [sqlite3_create_function()] or [sqlite3_create_function16()],
3864**          then the array of [sqlite3_value] objects passed as the
3865**          third parameter are always [protected sqlite3_value] objects.
3866*/
3867int sqlite3_create_function(
3868  sqlite3 *db,
3869  const char *zFunctionName,
3870  int nArg,
3871  int eTextRep,
3872  void *pApp,
3873  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3874  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3875  void (*xFinal)(sqlite3_context*)
3876);
3877int sqlite3_create_function16(
3878  sqlite3 *db,
3879  const void *zFunctionName,
3880  int nArg,
3881  int eTextRep,
3882  void *pApp,
3883  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3884  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3885  void (*xFinal)(sqlite3_context*)
3886);
3887
3888/*
3889** CAPI3REF: Text Encodings {H10267} <S50200> <H16100>
3890**
3891** These constant define integer codes that represent the various
3892** text encodings supported by SQLite.
3893*/
3894#define SQLITE_UTF8           1
3895#define SQLITE_UTF16LE        2
3896#define SQLITE_UTF16BE        3
3897#define SQLITE_UTF16          4    /* Use native byte order */
3898#define SQLITE_ANY            5    /* sqlite3_create_function only */
3899#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
3900
3901/*
3902** CAPI3REF: Obsolete Functions
3903**
3904** These functions are all now obsolete.  In order to maintain
3905** backwards compatibility with older code, we continue to support
3906** these functions.  However, new development projects should avoid
3907** the use of these functions.  To help encourage people to avoid
3908** using these functions, we are not going to tell you want they do.
3909*/
3910int sqlite3_aggregate_count(sqlite3_context*);
3911int sqlite3_expired(sqlite3_stmt*);
3912int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
3913int sqlite3_global_recover(void);
3914void sqlite3_thread_cleanup(void);
3915int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
3916
3917/*
3918** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
3919**
3920** The C-language implementation of SQL functions and aggregates uses
3921** this set of interface routines to access the parameter values on
3922** the function or aggregate.
3923**
3924** The xFunc (for scalar functions) or xStep (for aggregates) parameters
3925** to [sqlite3_create_function()] and [sqlite3_create_function16()]
3926** define callbacks that implement the SQL functions and aggregates.
3927** The 4th parameter to these callbacks is an array of pointers to
3928** [protected sqlite3_value] objects.  There is one [sqlite3_value] object for
3929** each parameter to the SQL function.  These routines are used to
3930** extract values from the [sqlite3_value] objects.
3931**
3932** These routines work only with [protected sqlite3_value] objects.
3933** Any attempt to use these routines on an [unprotected sqlite3_value]
3934** object results in undefined behavior.
3935**
3936** These routines work just like the corresponding [column access functions]
3937** except that  these routines take a single [protected sqlite3_value] object
3938** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
3939**
3940** The sqlite3_value_text16() interface extracts a UTF-16 string
3941** in the native byte-order of the host machine.  The
3942** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
3943** extract UTF-16 strings as big-endian and little-endian respectively.
3944**
3945** The sqlite3_value_numeric_type() interface attempts to apply
3946** numeric affinity to the value.  This means that an attempt is
3947** made to convert the value to an integer or floating point.  If
3948** such a conversion is possible without loss of information (in other
3949** words, if the value is a string that looks like a number)
3950** then the conversion is performed.  Otherwise no conversion occurs.
3951** The [SQLITE_INTEGER | datatype] after conversion is returned.
3952**
3953** Please pay particular attention to the fact that the pointer returned
3954** from [sqlite3_value_blob()], [sqlite3_value_text()], or
3955** [sqlite3_value_text16()] can be invalidated by a subsequent call to
3956** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
3957** or [sqlite3_value_text16()].
3958**
3959** These routines must be called from the same thread as
3960** the SQL function that supplied the [sqlite3_value*] parameters.
3961**
3962** INVARIANTS:
3963**
3964** {H15103} The [sqlite3_value_blob(V)] interface converts the
3965**          [protected sqlite3_value] object V into a BLOB and then
3966**          returns a pointer to the converted value.
3967**
3968** {H15106} The [sqlite3_value_bytes(V)] interface returns the
3969**          number of bytes in the BLOB or string (exclusive of the
3970**          zero terminator on the string) that was returned by the
3971**          most recent call to [sqlite3_value_blob(V)] or
3972**          [sqlite3_value_text(V)].
3973**
3974** {H15109} The [sqlite3_value_bytes16(V)] interface returns the
3975**          number of bytes in the string (exclusive of the
3976**          zero terminator on the string) that was returned by the
3977**          most recent call to [sqlite3_value_text16(V)],
3978**          [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)].
3979**
3980** {H15112} The [sqlite3_value_double(V)] interface converts the
3981**          [protected sqlite3_value] object V into a floating point value and
3982**          returns a copy of that value.
3983**
3984** {H15115} The [sqlite3_value_int(V)] interface converts the
3985**          [protected sqlite3_value] object V into a 64-bit signed integer and
3986**          returns the lower 32 bits of that integer.
3987**
3988** {H15118} The [sqlite3_value_int64(V)] interface converts the
3989**          [protected sqlite3_value] object V into a 64-bit signed integer and
3990**          returns a copy of that integer.
3991**
3992** {H15121} The [sqlite3_value_text(V)] interface converts the
3993**          [protected sqlite3_value] object V into a zero-terminated UTF-8
3994**          string and returns a pointer to that string.
3995**
3996** {H15124} The [sqlite3_value_text16(V)] interface converts the
3997**          [protected sqlite3_value] object V into a zero-terminated 2-byte
3998**          aligned UTF-16 native byte order
3999**          string and returns a pointer to that string.
4000**
4001** {H15127} The [sqlite3_value_text16be(V)] interface converts the
4002**          [protected sqlite3_value] object V into a zero-terminated 2-byte
4003**          aligned UTF-16 big-endian
4004**          string and returns a pointer to that string.
4005**
4006** {H15130} The [sqlite3_value_text16le(V)] interface converts the
4007**          [protected sqlite3_value] object V into a zero-terminated 2-byte
4008**          aligned UTF-16 little-endian
4009**          string and returns a pointer to that string.
4010**
4011** {H15133} The [sqlite3_value_type(V)] interface returns
4012**          one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
4013**          [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
4014**          the [sqlite3_value] object V.
4015**
4016** {H15136} The [sqlite3_value_numeric_type(V)] interface converts
4017**          the [protected sqlite3_value] object V into either an integer or
4018**          a floating point value if it can do so without loss of
4019**          information, and returns one of [SQLITE_NULL],
4020**          [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or
4021**          [SQLITE_BLOB] as appropriate for the
4022**          [protected sqlite3_value] object V after the conversion attempt.
4023*/
4024const void *sqlite3_value_blob(sqlite3_value*);
4025int sqlite3_value_bytes(sqlite3_value*);
4026int sqlite3_value_bytes16(sqlite3_value*);
4027double sqlite3_value_double(sqlite3_value*);
4028int sqlite3_value_int(sqlite3_value*);
4029sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
4030const unsigned char *sqlite3_value_text(sqlite3_value*);
4031const void *sqlite3_value_text16(sqlite3_value*);
4032const void *sqlite3_value_text16le(sqlite3_value*);
4033const void *sqlite3_value_text16be(sqlite3_value*);
4034int sqlite3_value_type(sqlite3_value*);
4035int sqlite3_value_numeric_type(sqlite3_value*);
4036
4037/*
4038** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200>
4039**
4040** The implementation of aggregate SQL functions use this routine to allocate
4041** a structure for storing their state.
4042**
4043** The first time the sqlite3_aggregate_context() routine is called for a
4044** particular aggregate, SQLite allocates nBytes of memory, zeroes out that
4045** memory, and returns a pointer to it. On second and subsequent calls to
4046** sqlite3_aggregate_context() for the same aggregate function index,
4047** the same buffer is returned. The implementation of the aggregate can use
4048** the returned buffer to accumulate data.
4049**
4050** SQLite automatically frees the allocated buffer when the aggregate
4051** query concludes.
4052**
4053** The first parameter should be a copy of the
4054** [sqlite3_context | SQL function context] that is the first parameter
4055** to the callback routine that implements the aggregate function.
4056**
4057** This routine must be called from the same thread in which
4058** the aggregate SQL function is running.
4059**
4060** INVARIANTS:
4061**
4062** {H16211} The first invocation of [sqlite3_aggregate_context(C,N)] for
4063**          a particular instance of an aggregate function (for a particular
4064**          context C) causes SQLite to allocate N bytes of memory,
4065**          zero that memory, and return a pointer to the allocated memory.
4066**
4067** {H16213} If a memory allocation error occurs during
4068**          [sqlite3_aggregate_context(C,N)] then the function returns 0.
4069**
4070** {H16215} Second and subsequent invocations of
4071**          [sqlite3_aggregate_context(C,N)] for the same context pointer C
4072**          ignore the N parameter and return a pointer to the same
4073**          block of memory returned by the first invocation.
4074**
4075** {H16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is
4076**          automatically freed on the next call to [sqlite3_reset()]
4077**          or [sqlite3_finalize()] for the [prepared statement] containing
4078**          the aggregate function associated with context C.
4079*/
4080void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
4081
4082/*
4083** CAPI3REF: User Data For Functions {H16240} <S20200>
4084**
4085** The sqlite3_user_data() interface returns a copy of
4086** the pointer that was the pUserData parameter (the 5th parameter)
4087** of the [sqlite3_create_function()]
4088** and [sqlite3_create_function16()] routines that originally
4089** registered the application defined function. {END}
4090**
4091** This routine must be called from the same thread in which
4092** the application-defined function is running.
4093**
4094** INVARIANTS:
4095**
4096** {H16243} The [sqlite3_user_data(C)] interface returns a copy of the
4097**          P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
4098**          or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
4099**          registered the SQL function associated with [sqlite3_context] C.
4100*/
4101void *sqlite3_user_data(sqlite3_context*);
4102
4103/*
4104** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200>
4105**
4106** The sqlite3_context_db_handle() interface returns a copy of
4107** the pointer to the [database connection] (the 1st parameter)
4108** of the [sqlite3_create_function()]
4109** and [sqlite3_create_function16()] routines that originally
4110** registered the application defined function.
4111**
4112** INVARIANTS:
4113**
4114** {H16253} The [sqlite3_context_db_handle(C)] interface returns a copy of the
4115**          D pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
4116**          or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
4117**          registered the SQL function associated with [sqlite3_context] C.
4118*/
4119sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
4120
4121/*
4122** CAPI3REF: Function Auxiliary Data {H16270} <S20200>
4123**
4124** The following two functions may be used by scalar SQL functions to
4125** associate metadata with argument values. If the same value is passed to
4126** multiple invocations of the same SQL function during query execution, under
4127** some circumstances the associated metadata may be preserved. This may
4128** be used, for example, to add a regular-expression matching scalar
4129** function. The compiled version of the regular expression is stored as
4130** metadata associated with the SQL value passed as the regular expression
4131** pattern.  The compiled regular expression can be reused on multiple
4132** invocations of the same function so that the original pattern string
4133** does not need to be recompiled on each invocation.
4134**
4135** The sqlite3_get_auxdata() interface returns a pointer to the metadata
4136** associated by the sqlite3_set_auxdata() function with the Nth argument
4137** value to the application-defined function. If no metadata has been ever
4138** been set for the Nth argument of the function, or if the corresponding
4139** function parameter has changed since the meta-data was set,
4140** then sqlite3_get_auxdata() returns a NULL pointer.
4141**
4142** The sqlite3_set_auxdata() interface saves the metadata
4143** pointed to by its 3rd parameter as the metadata for the N-th
4144** argument of the application-defined function.  Subsequent
4145** calls to sqlite3_get_auxdata() might return this data, if it has
4146** not been destroyed.
4147** If it is not NULL, SQLite will invoke the destructor
4148** function given by the 4th parameter to sqlite3_set_auxdata() on
4149** the metadata when the corresponding function parameter changes
4150** or when the SQL statement completes, whichever comes first.
4151**
4152** SQLite is free to call the destructor and drop metadata on any
4153** parameter of any function at any time.  The only guarantee is that
4154** the destructor will be called before the metadata is dropped.
4155**
4156** In practice, metadata is preserved between function calls for
4157** expressions that are constant at compile time. This includes literal
4158** values and SQL variables.
4159**
4160** These routines must be called from the same thread in which
4161** the SQL function is running.
4162**
4163** INVARIANTS:
4164**
4165** {H16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer
4166**          to metadata associated with the Nth parameter of the SQL function
4167**          whose context is C, or NULL if there is no metadata associated
4168**          with that parameter.
4169**
4170** {H16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata
4171**          pointer P to the Nth parameter of the SQL function with context C.
4172**
4173** {H16276} SQLite will invoke the destructor D with a single argument
4174**          which is the metadata pointer P following a call to
4175**          [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold
4176**          the metadata.
4177**
4178** {H16277} SQLite ceases to hold metadata for an SQL function parameter
4179**          when the value of that parameter changes.
4180**
4181** {H16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor
4182**          is called for any prior metadata associated with the same function
4183**          context C and parameter N.
4184**
4185** {H16279} SQLite will call destructors for any metadata it is holding
4186**          in a particular [prepared statement] S when either
4187**          [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called.
4188*/
4189void *sqlite3_get_auxdata(sqlite3_context*, int N);
4190void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
4191
4192
4193/*
4194** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100>
4195**
4196** These are special values for the destructor that is passed in as the
4197** final argument to routines like [sqlite3_result_blob()].  If the destructor
4198** argument is SQLITE_STATIC, it means that the content pointer is constant
4199** and will never change.  It does not need to be destroyed.  The
4200** SQLITE_TRANSIENT value means that the content will likely change in
4201** the near future and that SQLite should make its own private copy of
4202** the content before returning.
4203**
4204** The typedef is necessary to work around problems in certain
4205** C++ compilers.  See ticket #2191.
4206*/
4207typedef void (*sqlite3_destructor_type)(void*);
4208#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
4209#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
4210
4211/*
4212** CAPI3REF: Setting The Result Of An SQL Function {H16400} <S20200>
4213**
4214** These routines are used by the xFunc or xFinal callbacks that
4215** implement SQL functions and aggregates.  See
4216** [sqlite3_create_function()] and [sqlite3_create_function16()]
4217** for additional information.
4218**
4219** These functions work very much like the [parameter binding] family of
4220** functions used to bind values to host parameters in prepared statements.
4221** Refer to the [SQL parameter] documentation for additional information.
4222**
4223** The sqlite3_result_blob() interface sets the result from
4224** an application-defined function to be the BLOB whose content is pointed
4225** to by the second parameter and which is N bytes long where N is the
4226** third parameter.
4227**
4228** The sqlite3_result_zeroblob() interfaces set the result of
4229** the application-defined function to be a BLOB containing all zero
4230** bytes and N bytes in size, where N is the value of the 2nd parameter.
4231**
4232** The sqlite3_result_double() interface sets the result from
4233** an application-defined function to be a floating point value specified
4234** by its 2nd argument.
4235**
4236** The sqlite3_result_error() and sqlite3_result_error16() functions
4237** cause the implemented SQL function to throw an exception.
4238** SQLite uses the string pointed to by the
4239** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
4240** as the text of an error message.  SQLite interprets the error
4241** message string from sqlite3_result_error() as UTF-8. SQLite
4242** interprets the string from sqlite3_result_error16() as UTF-16 in native
4243** byte order.  If the third parameter to sqlite3_result_error()
4244** or sqlite3_result_error16() is negative then SQLite takes as the error
4245** message all text up through the first zero character.
4246** If the third parameter to sqlite3_result_error() or
4247** sqlite3_result_error16() is non-negative then SQLite takes that many
4248** bytes (not characters) from the 2nd parameter as the error message.
4249** The sqlite3_result_error() and sqlite3_result_error16()
4250** routines make a private copy of the error message text before
4251** they return.  Hence, the calling function can deallocate or
4252** modify the text after they return without harm.
4253** The sqlite3_result_error_code() function changes the error code
4254** returned by SQLite as a result of an error in a function.  By default,
4255** the error code is SQLITE_ERROR.  A subsequent call to sqlite3_result_error()
4256** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
4257**
4258** The sqlite3_result_toobig() interface causes SQLite to throw an error
4259** indicating that a string or BLOB is to long to represent.
4260**
4261** The sqlite3_result_nomem() interface causes SQLite to throw an error
4262** indicating that a memory allocation failed.
4263**
4264** The sqlite3_result_int() interface sets the return value
4265** of the application-defined function to be the 32-bit signed integer
4266** value given in the 2nd argument.
4267** The sqlite3_result_int64() interface sets the return value
4268** of the application-defined function to be the 64-bit signed integer
4269** value given in the 2nd argument.
4270**
4271** The sqlite3_result_null() interface sets the return value
4272** of the application-defined function to be NULL.
4273**
4274** The sqlite3_result_text(), sqlite3_result_text16(),
4275** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
4276** set the return value of the application-defined function to be
4277** a text string which is represented as UTF-8, UTF-16 native byte order,
4278** UTF-16 little endian, or UTF-16 big endian, respectively.
4279** SQLite takes the text result from the application from
4280** the 2nd parameter of the sqlite3_result_text* interfaces.
4281** If the 3rd parameter to the sqlite3_result_text* interfaces
4282** is negative, then SQLite takes result text from the 2nd parameter
4283** through the first zero character.
4284** If the 3rd parameter to the sqlite3_result_text* interfaces
4285** is non-negative, then as many bytes (not characters) of the text
4286** pointed to by the 2nd parameter are taken as the application-defined
4287** function result.
4288** If the 4th parameter to the sqlite3_result_text* interfaces
4289** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
4290** function as the destructor on the text or BLOB result when it has
4291** finished using that result.
4292** If the 4th parameter to the sqlite3_result_text* interfaces or
4293** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
4294** assumes that the text or BLOB result is in constant space and does not
4295** copy the it or call a destructor when it has finished using that result.
4296** If the 4th parameter to the sqlite3_result_text* interfaces
4297** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
4298** then SQLite makes a copy of the result into space obtained from
4299** from [sqlite3_malloc()] before it returns.
4300**
4301** The sqlite3_result_value() interface sets the result of
4302** the application-defined function to be a copy the
4303** [unprotected sqlite3_value] object specified by the 2nd parameter.  The
4304** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
4305** so that the [sqlite3_value] specified in the parameter may change or
4306** be deallocated after sqlite3_result_value() returns without harm.
4307** A [protected sqlite3_value] object may always be used where an
4308** [unprotected sqlite3_value] object is required, so either
4309** kind of [sqlite3_value] object can be used with this interface.
4310**
4311** If these routines are called from within the different thread
4312** than the one containing the application-defined function that received
4313** the [sqlite3_context] pointer, the results are undefined.
4314**
4315** INVARIANTS:
4316**
4317** {H16403} The default return value from any SQL function is NULL.
4318**
4319** {H16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the
4320**          return value of function C to be a BLOB that is N bytes
4321**          in length and with content pointed to by V.
4322**
4323** {H16409} The [sqlite3_result_double(C,V)] interface changes the
4324**          return value of function C to be the floating point value V.
4325**
4326** {H16412} The [sqlite3_result_error(C,V,N)] interface changes the return
4327**          value of function C to be an exception with error code
4328**          [SQLITE_ERROR] and a UTF-8 error message copied from V up to the
4329**          first zero byte or until N bytes are read if N is positive.
4330**
4331** {H16415} The [sqlite3_result_error16(C,V,N)] interface changes the return
4332**          value of function C to be an exception with error code
4333**          [SQLITE_ERROR] and a UTF-16 native byte order error message
4334**          copied from V up to the first zero terminator or until N bytes
4335**          are read if N is positive.
4336**
4337** {H16418} The [sqlite3_result_error_toobig(C)] interface changes the return
4338**          value of the function C to be an exception with error code
4339**          [SQLITE_TOOBIG] and an appropriate error message.
4340**
4341** {H16421} The [sqlite3_result_error_nomem(C)] interface changes the return
4342**          value of the function C to be an exception with error code
4343**          [SQLITE_NOMEM] and an appropriate error message.
4344**
4345** {H16424} The [sqlite3_result_error_code(C,E)] interface changes the return
4346**          value of the function C to be an exception with error code E.
4347**          The error message text is unchanged.
4348**
4349** {H16427} The [sqlite3_result_int(C,V)] interface changes the
4350**          return value of function C to be the 32-bit integer value V.
4351**
4352** {H16430} The [sqlite3_result_int64(C,V)] interface changes the
4353**          return value of function C to be the 64-bit integer value V.
4354**
4355** {H16433} The [sqlite3_result_null(C)] interface changes the
4356**          return value of function C to be NULL.
4357**
4358** {H16436} The [sqlite3_result_text(C,V,N,D)] interface changes the
4359**          return value of function C to be the UTF-8 string
4360**          V up to the first zero if N is negative
4361**          or the first N bytes of V if N is non-negative.
4362**
4363** {H16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the
4364**          return value of function C to be the UTF-16 native byte order
4365**          string V up to the first zero if N is negative
4366**          or the first N bytes of V if N is non-negative.
4367**
4368** {H16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the
4369**          return value of function C to be the UTF-16 big-endian
4370**          string V up to the first zero if N is negative
4371**          or the first N bytes or V if N is non-negative.
4372**
4373** {H16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the
4374**          return value of function C to be the UTF-16 little-endian
4375**          string V up to the first zero if N is negative
4376**          or the first N bytes of V if N is non-negative.
4377**
4378** {H16448} The [sqlite3_result_value(C,V)] interface changes the
4379**          return value of function C to be the [unprotected sqlite3_value]
4380**          object V.
4381**
4382** {H16451} The [sqlite3_result_zeroblob(C,N)] interface changes the
4383**          return value of function C to be an N-byte BLOB of all zeros.
4384**
4385** {H16454} The [sqlite3_result_error()] and [sqlite3_result_error16()]
4386**          interfaces make a copy of their error message strings before
4387**          returning.
4388**
4389** {H16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
4390**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
4391**          [sqlite3_result_text16be(C,V,N,D)], or
4392**          [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC]
4393**          then no destructor is ever called on the pointer V and SQLite
4394**          assumes that V is immutable.
4395**
4396** {H16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
4397**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
4398**          [sqlite3_result_text16be(C,V,N,D)], or
4399**          [sqlite3_result_text16le(C,V,N,D)] is the constant
4400**          [SQLITE_TRANSIENT] then the interfaces makes a copy of the
4401**          content of V and retains the copy.
4402**
4403** {H16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
4404**          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
4405**          [sqlite3_result_text16be(C,V,N,D)], or
4406**          [sqlite3_result_text16le(C,V,N,D)] is some value other than
4407**          the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then
4408**          SQLite will invoke the destructor D with V as its only argument
4409**          when it has finished with the V value.
4410*/
4411void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
4412void sqlite3_result_double(sqlite3_context*, double);
4413void sqlite3_result_error(sqlite3_context*, const char*, int);
4414void sqlite3_result_error16(sqlite3_context*, const void*, int);
4415void sqlite3_result_error_toobig(sqlite3_context*);
4416void sqlite3_result_error_nomem(sqlite3_context*);
4417void sqlite3_result_error_code(sqlite3_context*, int);
4418void sqlite3_result_int(sqlite3_context*, int);
4419void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
4420void sqlite3_result_null(sqlite3_context*);
4421void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
4422void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
4423void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
4424void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
4425void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
4426void sqlite3_result_zeroblob(sqlite3_context*, int n);
4427
4428/*
4429** CAPI3REF: Define New Collating Sequences {H16600} <S20300>
4430**
4431** These functions are used to add new collation sequences to the
4432** [database connection] specified as the first argument.
4433**
4434** The name of the new collation sequence is specified as a UTF-8 string
4435** for sqlite3_create_collation() and sqlite3_create_collation_v2()
4436** and a UTF-16 string for sqlite3_create_collation16(). In all cases
4437** the name is passed as the second function argument.
4438**
4439** The third argument may be one of the constants [SQLITE_UTF8],
4440** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
4441** routine expects to be passed pointers to strings encoded using UTF-8,
4442** UTF-16 little-endian, or UTF-16 big-endian, respectively. The
4443** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that
4444** the routine expects pointers to 16-bit word aligned strings
4445** of UTF-16 in the native byte order of the host computer.
4446**
4447** A pointer to the user supplied routine must be passed as the fifth
4448** argument.  If it is NULL, this is the same as deleting the collation
4449** sequence (so that SQLite cannot call it anymore).
4450** Each time the application supplied function is invoked, it is passed
4451** as its first parameter a copy of the void* passed as the fourth argument
4452** to sqlite3_create_collation() or sqlite3_create_collation16().
4453**
4454** The remaining arguments to the application-supplied routine are two strings,
4455** each represented by a (length, data) pair and encoded in the encoding
4456** that was passed as the third argument when the collation sequence was
4457** registered. {END}  The application defined collation routine should
4458** return negative, zero or positive if the first string is less than,
4459** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
4460**
4461** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
4462** except that it takes an extra argument which is a destructor for
4463** the collation.  The destructor is called when the collation is
4464** destroyed and is passed a copy of the fourth parameter void* pointer
4465** of the sqlite3_create_collation_v2().
4466** Collations are destroyed when they are overridden by later calls to the
4467** collation creation functions or when the [database connection] is closed
4468** using [sqlite3_close()].
4469**
4470** INVARIANTS:
4471**
4472** {H16603} A successful call to the
4473**          [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface
4474**          registers function F as the comparison function used to
4475**          implement collation X on the [database connection] B for
4476**          databases having encoding E.
4477**
4478** {H16604} SQLite understands the X parameter to
4479**          [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated
4480**          UTF-8 string in which case is ignored for ASCII characters and
4481**          is significant for non-ASCII characters.
4482**
4483** {H16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)]
4484**          with the same values for B, X, and E, override prior values
4485**          of P, F, and D.
4486**
4487** {H16609} If the destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
4488**          is not NULL then it is called with argument P when the
4489**          collating function is dropped by SQLite.
4490**
4491** {H16612} A collating function is dropped when it is overloaded.
4492**
4493** {H16615} A collating function is dropped when the database connection
4494**          is closed using [sqlite3_close()].
4495**
4496** {H16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
4497**          is passed through as the first parameter to the comparison
4498**          function F for all subsequent invocations of F.
4499**
4500** {H16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly
4501**          the same as a call to [sqlite3_create_collation_v2()] with
4502**          the same parameters and a NULL destructor.
4503**
4504** {H16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)],
4505**          SQLite uses the comparison function F for all text comparison
4506**          operations on the [database connection] B on text values that
4507**          use the collating sequence named X.
4508**
4509** {H16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same
4510**          as [sqlite3_create_collation(B,X,E,P,F)] except that the
4511**          collation name X is understood as UTF-16 in native byte order
4512**          instead of UTF-8.
4513**
4514** {H16630} When multiple comparison functions are available for the same
4515**          collating sequence, SQLite chooses the one whose text encoding
4516**          requires the least amount of conversion from the default
4517**          text encoding of the database.
4518*/
4519int sqlite3_create_collation(
4520  sqlite3*,
4521  const char *zName,
4522  int eTextRep,
4523  void*,
4524  int(*xCompare)(void*,int,const void*,int,const void*)
4525);
4526int sqlite3_create_collation_v2(
4527  sqlite3*,
4528  const char *zName,
4529  int eTextRep,
4530  void*,
4531  int(*xCompare)(void*,int,const void*,int,const void*),
4532  void(*xDestroy)(void*)
4533);
4534int sqlite3_create_collation16(
4535  sqlite3*,
4536  const void *zName,
4537  int eTextRep,
4538  void*,
4539  int(*xCompare)(void*,int,const void*,int,const void*)
4540);
4541
4542/*
4543** CAPI3REF: Collation Needed Callbacks {H16700} <S20300>
4544**
4545** To avoid having to register all collation sequences before a database
4546** can be used, a single callback function may be registered with the
4547** [database connection] to be called whenever an undefined collation
4548** sequence is required.
4549**
4550** If the function is registered using the sqlite3_collation_needed() API,
4551** then it is passed the names of undefined collation sequences as strings
4552** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used,
4553** the names are passed as UTF-16 in machine native byte order.
4554** A call to either function replaces any existing callback.
4555**
4556** When the callback is invoked, the first argument passed is a copy
4557** of the second argument to sqlite3_collation_needed() or
4558** sqlite3_collation_needed16().  The second argument is the database
4559** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
4560** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
4561** sequence function required.  The fourth parameter is the name of the
4562** required collation sequence.
4563**
4564** The callback function should register the desired collation using
4565** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
4566** [sqlite3_create_collation_v2()].
4567**
4568** INVARIANTS:
4569**
4570** {H16702} A successful call to [sqlite3_collation_needed(D,P,F)]
4571**          or [sqlite3_collation_needed16(D,P,F)] causes
4572**          the [database connection] D to invoke callback F with first
4573**          parameter P whenever it needs a comparison function for a
4574**          collating sequence that it does not know about.
4575**
4576** {H16704} Each successful call to [sqlite3_collation_needed()] or
4577**          [sqlite3_collation_needed16()] overrides the callback registered
4578**          on the same [database connection] by prior calls to either
4579**          interface.
4580**
4581** {H16706} The name of the requested collating function passed in the
4582**          4th parameter to the callback is in UTF-8 if the callback
4583**          was registered using [sqlite3_collation_needed()] and
4584**          is in UTF-16 native byte order if the callback was
4585**          registered using [sqlite3_collation_needed16()].
4586*/
4587int sqlite3_collation_needed(
4588  sqlite3*,
4589  void*,
4590  void(*)(void*,sqlite3*,int eTextRep,const char*)
4591);
4592int sqlite3_collation_needed16(
4593  sqlite3*,
4594  void*,
4595  void(*)(void*,sqlite3*,int eTextRep,const void*)
4596);
4597
4598/*
4599** Specify the key for an encrypted database.  This routine should be
4600** called right after sqlite3_open().
4601**
4602** The code to implement this API is not available in the public release
4603** of SQLite.
4604*/
4605int sqlite3_key(
4606  sqlite3 *db,                   /* Database to be rekeyed */
4607  const void *pKey, int nKey     /* The key */
4608);
4609
4610/*
4611** Change the key on an open database.  If the current database is not
4612** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
4613** database is decrypted.
4614**
4615** The code to implement this API is not available in the public release
4616** of SQLite.
4617*/
4618int sqlite3_rekey(
4619  sqlite3 *db,                   /* Database to be rekeyed */
4620  const void *pKey, int nKey     /* The new key */
4621);
4622
4623/*
4624** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410>
4625**
4626** The sqlite3_sleep() function causes the current thread to suspend execution
4627** for at least a number of milliseconds specified in its parameter.
4628**
4629** If the operating system does not support sleep requests with
4630** millisecond time resolution, then the time will be rounded up to
4631** the nearest second. The number of milliseconds of sleep actually
4632** requested from the operating system is returned.
4633**
4634** SQLite implements this interface by calling the xSleep()
4635** method of the default [sqlite3_vfs] object.
4636**
4637** INVARIANTS:
4638**
4639** {H10533} The [sqlite3_sleep(M)] interface invokes the xSleep
4640**          method of the default [sqlite3_vfs|VFS] in order to
4641**          suspend execution of the current thread for at least
4642**          M milliseconds.
4643**
4644** {H10536} The [sqlite3_sleep(M)] interface returns the number of
4645**          milliseconds of sleep actually requested of the operating
4646**          system, which might be larger than the parameter M.
4647*/
4648int sqlite3_sleep(int);
4649
4650/*
4651** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000>
4652**
4653** If this global variable is made to point to a string which is
4654** the name of a folder (a.k.a. directory), then all temporary files
4655** created by SQLite will be placed in that directory.  If this variable
4656** is a NULL pointer, then SQLite performs a search for an appropriate
4657** temporary file directory.
4658**
4659** It is not safe to modify this variable once a [database connection]
4660** has been opened.  It is intended that this variable be set once
4661** as part of process initialization and before any SQLite interface
4662** routines have been call and remain unchanged thereafter.
4663*/
4664SQLITE_EXTERN char *sqlite3_temp_directory;
4665
4666/*
4667** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200>
4668** KEYWORDS: {autocommit mode}
4669**
4670** The sqlite3_get_autocommit() interface returns non-zero or
4671** zero if the given database connection is or is not in autocommit mode,
4672** respectively.  Autocommit mode is on by default.
4673** Autocommit mode is disabled by a [BEGIN] statement.
4674** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
4675**
4676** If certain kinds of errors occur on a statement within a multi-statement
4677** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
4678** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
4679** transaction might be rolled back automatically.  The only way to
4680** find out whether SQLite automatically rolled back the transaction after
4681** an error is to use this function.
4682**
4683** INVARIANTS:
4684**
4685** {H12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or
4686**          zero if the [database connection] D is or is not in autocommit
4687**          mode, respectively.
4688**
4689** {H12932} Autocommit mode is on by default.
4690**
4691** {H12933} Autocommit mode is disabled by a successful [BEGIN] statement.
4692**
4693** {H12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK]
4694**          statement.
4695**
4696** ASSUMPTIONS:
4697**
4698** {A12936} If another thread changes the autocommit status of the database
4699**          connection while this routine is running, then the return value
4700**          is undefined.
4701*/
4702int sqlite3_get_autocommit(sqlite3*);
4703
4704/*
4705** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600>
4706**
4707** The sqlite3_db_handle interface returns the [database connection] handle
4708** to which a [prepared statement] belongs.  The database handle returned by
4709** sqlite3_db_handle is the same database handle that was the first argument
4710** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
4711** create the statement in the first place.
4712**
4713** INVARIANTS:
4714**
4715** {H13123} The [sqlite3_db_handle(S)] interface returns a pointer
4716**          to the [database connection] associated with the
4717**          [prepared statement] S.
4718*/
4719sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
4720
4721/*
4722** CAPI3REF: Find the next prepared statement {H13140} <S60600>
4723**
4724** This interface returns a pointer to the next [prepared statement] after
4725** pStmt associated with the [database connection] pDb.  If pStmt is NULL
4726** then this interface returns a pointer to the first prepared statement
4727** associated with the database connection pDb.  If no prepared statement
4728** satisfies the conditions of this routine, it returns NULL.
4729**
4730** INVARIANTS:
4731**
4732** {H13143} If D is a [database connection] that holds one or more
4733**          unfinalized [prepared statements] and S is a NULL pointer,
4734**          then [sqlite3_next_stmt(D, S)] routine shall return a pointer
4735**          to one of the prepared statements associated with D.
4736**
4737** {H13146} If D is a [database connection] that holds no unfinalized
4738**          [prepared statements] and S is a NULL pointer, then
4739**          [sqlite3_next_stmt(D, S)] routine shall return a NULL pointer.
4740**
4741** {H13149} If S is a [prepared statement] in the [database connection] D
4742**          and S is not the last prepared statement in D, then
4743**          [sqlite3_next_stmt(D, S)] routine shall return a pointer
4744**          to the next prepared statement in D after S.
4745**
4746** {H13152} If S is the last [prepared statement] in the
4747**          [database connection] D then the [sqlite3_next_stmt(D, S)]
4748**          routine shall return a NULL pointer.
4749**
4750** ASSUMPTIONS:
4751**
4752** {A13154} The [database connection] pointer D in a call to
4753**          [sqlite3_next_stmt(D,S)] must refer to an open database
4754**          connection and in particular must not be a NULL pointer.
4755*/
4756sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
4757
4758/*
4759** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400>
4760**
4761** The sqlite3_commit_hook() interface registers a callback
4762** function to be invoked whenever a transaction is committed.
4763** Any callback set by a previous call to sqlite3_commit_hook()
4764** for the same database connection is overridden.
4765** The sqlite3_rollback_hook() interface registers a callback
4766** function to be invoked whenever a transaction is committed.
4767** Any callback set by a previous call to sqlite3_commit_hook()
4768** for the same database connection is overridden.
4769** The pArg argument is passed through to the callback.
4770** If the callback on a commit hook function returns non-zero,
4771** then the commit is converted into a rollback.
4772**
4773** If another function was previously registered, its
4774** pArg value is returned.  Otherwise NULL is returned.
4775**
4776** Registering a NULL function disables the callback.
4777**
4778** For the purposes of this API, a transaction is said to have been
4779** rolled back if an explicit "ROLLBACK" statement is executed, or
4780** an error or constraint causes an implicit rollback to occur.
4781** The rollback callback is not invoked if a transaction is
4782** automatically rolled back because the database connection is closed.
4783** The rollback callback is not invoked if a transaction is
4784** rolled back because a commit callback returned non-zero.
4785** <todo> Check on this </todo>
4786**
4787** INVARIANTS:
4788**
4789** {H12951} The [sqlite3_commit_hook(D,F,P)] interface registers the
4790**          callback function F to be invoked with argument P whenever
4791**          a transaction commits on the [database connection] D.
4792**
4793** {H12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P argument
4794**          from the previous call with the same [database connection] D,
4795**          or NULL on the first call for a particular database connection D.
4796**
4797** {H12953} Each call to [sqlite3_commit_hook()] overwrites the callback
4798**          registered by prior calls.
4799**
4800** {H12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL
4801**          then the commit hook callback is canceled and no callback
4802**          is invoked when a transaction commits.
4803**
4804** {H12955} If the commit callback returns non-zero then the commit is
4805**          converted into a rollback.
4806**
4807** {H12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the
4808**          callback function F to be invoked with argument P whenever
4809**          a transaction rolls back on the [database connection] D.
4810**
4811** {H12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P
4812**          argument from the previous call with the same
4813**          [database connection] D, or NULL on the first call
4814**          for a particular database connection D.
4815**
4816** {H12963} Each call to [sqlite3_rollback_hook()] overwrites the callback
4817**          registered by prior calls.
4818**
4819** {H12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL
4820**          then the rollback hook callback is canceled and no callback
4821**          is invoked when a transaction rolls back.
4822*/
4823void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
4824void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
4825
4826/*
4827** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400>
4828**
4829** The sqlite3_update_hook() interface registers a callback function
4830** with the [database connection] identified by the first argument
4831** to be invoked whenever a row is updated, inserted or deleted.
4832** Any callback set by a previous call to this function
4833** for the same database connection is overridden.
4834**
4835** The second argument is a pointer to the function to invoke when a
4836** row is updated, inserted or deleted.
4837** The first argument to the callback is a copy of the third argument
4838** to sqlite3_update_hook().
4839** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
4840** or [SQLITE_UPDATE], depending on the operation that caused the callback
4841** to be invoked.
4842** The third and fourth arguments to the callback contain pointers to the
4843** database and table name containing the affected row.
4844** The final callback parameter is the rowid of the row. In the case of
4845** an update, this is the rowid after the update takes place.
4846**
4847** The update hook is not invoked when internal system tables are
4848** modified (i.e. sqlite_master and sqlite_sequence).
4849**
4850** If another function was previously registered, its pArg value
4851** is returned.  Otherwise NULL is returned.
4852**
4853** INVARIANTS:
4854**
4855** {H12971} The [sqlite3_update_hook(D,F,P)] interface causes the callback
4856**          function F to be invoked with first parameter P whenever
4857**          a table row is modified, inserted, or deleted on
4858**          the [database connection] D.
4859**
4860** {H12973} The [sqlite3_update_hook(D,F,P)] interface returns the value
4861**          of P for the previous call on the same [database connection] D,
4862**          or NULL for the first call.
4863**
4864** {H12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)]
4865**          is NULL then the no update callbacks are made.
4866**
4867** {H12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls
4868**          to the same interface on the same [database connection] D.
4869**
4870** {H12979} The update hook callback is not invoked when internal system
4871**          tables such as sqlite_master and sqlite_sequence are modified.
4872**
4873** {H12981} The second parameter to the update callback
4874**          is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
4875**          depending on the operation that caused the callback to be invoked.
4876**
4877** {H12983} The third and fourth arguments to the callback contain pointers
4878**          to zero-terminated UTF-8 strings which are the names of the
4879**          database and table that is being updated.
4880
4881** {H12985} The final callback parameter is the rowid of the row after
4882**          the change occurs.
4883*/
4884void *sqlite3_update_hook(
4885  sqlite3*,
4886  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
4887  void*
4888);
4889
4890/*
4891** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900>
4892** KEYWORDS: {shared cache} {shared cache mode}
4893**
4894** This routine enables or disables the sharing of the database cache
4895** and schema data structures between [database connection | connections]
4896** to the same database. Sharing is enabled if the argument is true
4897** and disabled if the argument is false.
4898**
4899** Cache sharing is enabled and disabled for an entire process. {END}
4900** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
4901** sharing was enabled or disabled for each thread separately.
4902**
4903** The cache sharing mode set by this interface effects all subsequent
4904** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
4905** Existing database connections continue use the sharing mode
4906** that was in effect at the time they were opened.
4907**
4908** Virtual tables cannot be used with a shared cache.  When shared
4909** cache is enabled, the [sqlite3_create_module()] API used to register
4910** virtual tables will always return an error.
4911**
4912** This routine returns [SQLITE_OK] if shared cache was enabled or disabled
4913** successfully.  An [error code] is returned otherwise.
4914**
4915** Shared cache is disabled by default. But this might change in
4916** future releases of SQLite.  Applications that care about shared
4917** cache setting should set it explicitly.
4918**
4919** INVARIANTS:
4920**
4921** {H10331} A successful invocation of [sqlite3_enable_shared_cache(B)]
4922**          will enable or disable shared cache mode for any subsequently
4923**          created [database connection] in the same process.
4924**
4925** {H10336} When shared cache is enabled, the [sqlite3_create_module()]
4926**          interface will always return an error.
4927**
4928** {H10337} The [sqlite3_enable_shared_cache(B)] interface returns
4929**          [SQLITE_OK] if shared cache was enabled or disabled successfully.
4930**
4931** {H10339} Shared cache is disabled by default.
4932*/
4933int sqlite3_enable_shared_cache(int);
4934
4935/*
4936** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220>
4937**
4938** The sqlite3_release_memory() interface attempts to free N bytes
4939** of heap memory by deallocating non-essential memory allocations
4940** held by the database library. {END}  Memory used to cache database
4941** pages to improve performance is an example of non-essential memory.
4942** sqlite3_release_memory() returns the number of bytes actually freed,
4943** which might be more or less than the amount requested.
4944**
4945** INVARIANTS:
4946**
4947** {H17341} The [sqlite3_release_memory(N)] interface attempts to
4948**          free N bytes of heap memory by deallocating non-essential
4949**          memory allocations held by the database library.
4950**
4951** {H16342} The [sqlite3_release_memory(N)] returns the number
4952**          of bytes actually freed, which might be more or less
4953**          than the amount requested.
4954*/
4955int sqlite3_release_memory(int);
4956
4957/*
4958** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220>
4959**
4960** The sqlite3_soft_heap_limit() interface places a "soft" limit
4961** on the amount of heap memory that may be allocated by SQLite.
4962** If an internal allocation is requested that would exceed the
4963** soft heap limit, [sqlite3_release_memory()] is invoked one or
4964** more times to free up some space before the allocation is performed.
4965**
4966** The limit is called "soft", because if [sqlite3_release_memory()]
4967** cannot free sufficient memory to prevent the limit from being exceeded,
4968** the memory is allocated anyway and the current operation proceeds.
4969**
4970** A negative or zero value for N means that there is no soft heap limit and
4971** [sqlite3_release_memory()] will only be called when memory is exhausted.
4972** The default value for the soft heap limit is zero.
4973**
4974** SQLite makes a best effort to honor the soft heap limit.
4975** But if the soft heap limit cannot be honored, execution will
4976** continue without error or notification.  This is why the limit is
4977** called a "soft" limit.  It is advisory only.
4978**
4979** Prior to SQLite version 3.5.0, this routine only constrained the memory
4980** allocated by a single thread - the same thread in which this routine
4981** runs.  Beginning with SQLite version 3.5.0, the soft heap limit is
4982** applied to all threads. The value specified for the soft heap limit
4983** is an upper bound on the total memory allocation for all threads. In
4984** version 3.5.0 there is no mechanism for limiting the heap usage for
4985** individual threads.
4986**
4987** INVARIANTS:
4988**
4989** {H16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit
4990**          of N bytes on the amount of heap memory that may be allocated
4991**          using [sqlite3_malloc()] or [sqlite3_realloc()] at any point
4992**          in time.
4993**
4994** {H16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would
4995**          cause the total amount of allocated memory to exceed the
4996**          soft heap limit, then [sqlite3_release_memory()] is invoked
4997**          in an attempt to reduce the memory usage prior to proceeding
4998**          with the memory allocation attempt.
4999**
5000** {H16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger
5001**          attempts to reduce memory usage through the soft heap limit
5002**          mechanism continue even if the attempt to reduce memory
5003**          usage is unsuccessful.
5004**
5005** {H16354} A negative or zero value for N in a call to
5006**          [sqlite3_soft_heap_limit(N)] means that there is no soft
5007**          heap limit and [sqlite3_release_memory()] will only be
5008**          called when memory is completely exhausted.
5009**
5010** {H16355} The default value for the soft heap limit is zero.
5011**
5012** {H16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the
5013**          values set by all prior calls.
5014*/
5015void sqlite3_soft_heap_limit(int);
5016
5017/*
5018** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300>
5019**
5020** This routine returns metadata about a specific column of a specific
5021** database table accessible using the [database connection] handle
5022** passed as the first function argument.
5023**
5024** The column is identified by the second, third and fourth parameters to
5025** this function. The second parameter is either the name of the database
5026** (i.e. "main", "temp" or an attached database) containing the specified
5027** table or NULL. If it is NULL, then all attached databases are searched
5028** for the table using the same algorithm used by the database engine to
5029** resolve unqualified table references.
5030**
5031** The third and fourth parameters to this function are the table and column
5032** name of the desired column, respectively. Neither of these parameters
5033** may be NULL.
5034**
5035** Metadata is returned by writing to the memory locations passed as the 5th
5036** and subsequent parameters to this function. Any of these arguments may be
5037** NULL, in which case the corresponding element of metadata is omitted.
5038**
5039** <blockquote>
5040** <table border="1">
5041** <tr><th> Parameter <th> Output<br>Type <th>  Description
5042**
5043** <tr><td> 5th <td> const char* <td> Data type
5044** <tr><td> 6th <td> const char* <td> Name of default collation sequence
5045** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
5046** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
5047** <tr><td> 9th <td> int         <td> True if column is AUTOINCREMENT
5048** </table>
5049** </blockquote>
5050**
5051** The memory pointed to by the character pointers returned for the
5052** declaration type and collation sequence is valid only until the next
5053** call to any SQLite API function.
5054**
5055** If the specified table is actually a view, an [error code] is returned.
5056**
5057** If the specified column is "rowid", "oid" or "_rowid_" and an
5058** INTEGER PRIMARY KEY column has been explicitly declared, then the output
5059** parameters are set for the explicitly declared column. If there is no
5060** explicitly declared INTEGER PRIMARY KEY column, then the output
5061** parameters are set as follows:
5062**
5063** <pre>
5064**     data type: "INTEGER"
5065**     collation sequence: "BINARY"
5066**     not null: 0
5067**     primary key: 1
5068**     auto increment: 0
5069** </pre>
5070**
5071** This function may load one or more schemas from database files. If an
5072** error occurs during this process, or if the requested table or column
5073** cannot be found, an [error code] is returned and an error message left
5074** in the [database connection] (to be retrieved using sqlite3_errmsg()).
5075**
5076** This API is only available if the library was compiled with the
5077** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
5078*/
5079int sqlite3_table_column_metadata(
5080  sqlite3 *db,                /* Connection handle */
5081  const char *zDbName,        /* Database name or NULL */
5082  const char *zTableName,     /* Table name */
5083  const char *zColumnName,    /* Column name */
5084  char const **pzDataType,    /* OUTPUT: Declared data type */
5085  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
5086  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
5087  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
5088  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
5089);
5090
5091/*
5092** CAPI3REF: Load An Extension {H12600} <S20500>
5093**
5094** This interface loads an SQLite extension library from the named file.
5095**
5096** {H12601} The sqlite3_load_extension() interface attempts to load an
5097**          SQLite extension library contained in the file zFile.
5098**
5099** {H12602} The entry point is zProc.
5100**
5101** {H12603} zProc may be 0, in which case the name of the entry point
5102**          defaults to "sqlite3_extension_init".
5103**
5104** {H12604} The sqlite3_load_extension() interface shall return
5105**          [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
5106**
5107** {H12605} If an error occurs and pzErrMsg is not 0, then the
5108**          [sqlite3_load_extension()] interface shall attempt to
5109**          fill *pzErrMsg with error message text stored in memory
5110**          obtained from [sqlite3_malloc()]. {END}  The calling function
5111**          should free this memory by calling [sqlite3_free()].
5112**
5113** {H12606} Extension loading must be enabled using
5114**          [sqlite3_enable_load_extension()] prior to calling this API,
5115**          otherwise an error will be returned.
5116*/
5117int sqlite3_load_extension(
5118  sqlite3 *db,          /* Load the extension into this database connection */
5119  const char *zFile,    /* Name of the shared library containing extension */
5120  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
5121  char **pzErrMsg       /* Put error message here if not 0 */
5122);
5123
5124/*
5125** CAPI3REF: Enable Or Disable Extension Loading {H12620} <S20500>
5126**
5127** So as not to open security holes in older applications that are
5128** unprepared to deal with extension loading, and as a means of disabling
5129** extension loading while evaluating user-entered SQL, the following API
5130** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
5131**
5132** Extension loading is off by default. See ticket #1863.
5133**
5134** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1
5135**          to turn extension loading on and call it with onoff==0 to turn
5136**          it back off again.
5137**
5138** {H12622} Extension loading is off by default.
5139*/
5140int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
5141
5142/*
5143** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
5144**
5145** This API can be invoked at program startup in order to register
5146** one or more statically linked extensions that will be available
5147** to all new [database connections]. {END}
5148**
5149** This routine stores a pointer to the extension in an array that is
5150** obtained from [sqlite3_malloc()].  If you run a memory leak checker
5151** on your program and it reports a leak because of this array, invoke
5152** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
5153**
5154** {H12641} This function registers an extension entry point that is
5155**          automatically invoked whenever a new [database connection]
5156**          is opened using [sqlite3_open()], [sqlite3_open16()],
5157**          or [sqlite3_open_v2()].
5158**
5159** {H12642} Duplicate extensions are detected so calling this routine
5160**          multiple times with the same extension is harmless.
5161**
5162** {H12643} This routine stores a pointer to the extension in an array
5163**          that is obtained from [sqlite3_malloc()].
5164**
5165** {H12644} Automatic extensions apply across all threads.
5166*/
5167int sqlite3_auto_extension(void *xEntryPoint);
5168
5169/*
5170** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
5171**
5172** This function disables all previously registered automatic
5173** extensions. {END}  It undoes the effect of all prior
5174** [sqlite3_auto_extension()] calls.
5175**
5176** {H12661} This function disables all previously registered
5177**          automatic extensions.
5178**
5179** {H12662} This function disables automatic extensions in all threads.
5180*/
5181void sqlite3_reset_auto_extension(void);
5182
5183/*
5184****** EXPERIMENTAL - subject to change without notice **************
5185**
5186** The interface to the virtual-table mechanism is currently considered
5187** to be experimental.  The interface might change in incompatible ways.
5188** If this is a problem for you, do not use the interface at this time.
5189**
5190** When the virtual-table mechanism stabilizes, we will declare the
5191** interface fixed, support it indefinitely, and remove this comment.
5192*/
5193
5194/*
5195** Structures used by the virtual table interface
5196*/
5197typedef struct sqlite3_vtab sqlite3_vtab;
5198typedef struct sqlite3_index_info sqlite3_index_info;
5199typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
5200typedef struct sqlite3_module sqlite3_module;
5201
5202/*
5203** CAPI3REF: Virtual Table Object {H18000} <S20400>
5204** KEYWORDS: sqlite3_module
5205**
5206** A module is a class of virtual tables.  Each module is defined
5207** by an instance of the following structure.  This structure consists
5208** mostly of methods for the module.
5209**
5210** This interface is experimental and is subject to change or
5211** removal in future releases of SQLite.
5212*/
5213struct sqlite3_module {
5214  int iVersion;
5215  int (*xCreate)(sqlite3*, void *pAux,
5216               int argc, const char *const*argv,
5217               sqlite3_vtab **ppVTab, char**);
5218  int (*xConnect)(sqlite3*, void *pAux,
5219               int argc, const char *const*argv,
5220               sqlite3_vtab **ppVTab, char**);
5221  int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
5222  int (*xDisconnect)(sqlite3_vtab *pVTab);
5223  int (*xDestroy)(sqlite3_vtab *pVTab);
5224  int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
5225  int (*xClose)(sqlite3_vtab_cursor*);
5226  int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
5227                int argc, sqlite3_value **argv);
5228  int (*xNext)(sqlite3_vtab_cursor*);
5229  int (*xEof)(sqlite3_vtab_cursor*);
5230  int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
5231  int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
5232  int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
5233  int (*xBegin)(sqlite3_vtab *pVTab);
5234  int (*xSync)(sqlite3_vtab *pVTab);
5235  int (*xCommit)(sqlite3_vtab *pVTab);
5236  int (*xRollback)(sqlite3_vtab *pVTab);
5237  int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
5238                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
5239                       void **ppArg);
5240  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
5241};
5242
5243/*
5244** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400>
5245** KEYWORDS: sqlite3_index_info
5246**
5247** The sqlite3_index_info structure and its substructures is used to
5248** pass information into and receive the reply from the xBestIndex
5249** method of an sqlite3_module.  The fields under **Inputs** are the
5250** inputs to xBestIndex and are read-only.  xBestIndex inserts its
5251** results into the **Outputs** fields.
5252**
5253** The aConstraint[] array records WHERE clause constraints of the form:
5254**
5255** <pre>column OP expr</pre>
5256**
5257** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.  The particular operator is
5258** stored in aConstraint[].op.  The index of the column is stored in
5259** aConstraint[].iColumn.  aConstraint[].usable is TRUE if the
5260** expr on the right-hand side can be evaluated (and thus the constraint
5261** is usable) and false if it cannot.
5262**
5263** The optimizer automatically inverts terms of the form "expr OP column"
5264** and makes other simplifications to the WHERE clause in an attempt to
5265** get as many WHERE clause terms into the form shown above as possible.
5266** The aConstraint[] array only reports WHERE clause terms in the correct
5267** form that refer to the particular virtual table being queried.
5268**
5269** Information about the ORDER BY clause is stored in aOrderBy[].
5270** Each term of aOrderBy records a column of the ORDER BY clause.
5271**
5272** The xBestIndex method must fill aConstraintUsage[] with information
5273** about what parameters to pass to xFilter.  If argvIndex>0 then
5274** the right-hand side of the corresponding aConstraint[] is evaluated
5275** and becomes the argvIndex-th entry in argv.  If aConstraintUsage[].omit
5276** is true, then the constraint is assumed to be fully handled by the
5277** virtual table and is not checked again by SQLite.
5278**
5279** The idxNum and idxPtr values are recorded and passed into xFilter.
5280** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
5281**
5282** The orderByConsumed means that output from xFilter will occur in
5283** the correct order to satisfy the ORDER BY clause so that no separate
5284** sorting step is required.
5285**
5286** The estimatedCost value is an estimate of the cost of doing the
5287** particular lookup.  A full scan of a table with N entries should have
5288** a cost of N.  A binary search of a table of N entries should have a
5289** cost of approximately log(N).
5290**
5291** This interface is experimental and is subject to change or
5292** removal in future releases of SQLite.
5293*/
5294struct sqlite3_index_info {
5295  /* Inputs */
5296  int nConstraint;           /* Number of entries in aConstraint */
5297  struct sqlite3_index_constraint {
5298     int iColumn;              /* Column on left-hand side of constraint */
5299     unsigned char op;         /* Constraint operator */
5300     unsigned char usable;     /* True if this constraint is usable */
5301     int iTermOffset;          /* Used internally - xBestIndex should ignore */
5302  } *aConstraint;            /* Table of WHERE clause constraints */
5303  int nOrderBy;              /* Number of terms in the ORDER BY clause */
5304  struct sqlite3_index_orderby {
5305     int iColumn;              /* Column number */
5306     unsigned char desc;       /* True for DESC.  False for ASC. */
5307  } *aOrderBy;               /* The ORDER BY clause */
5308  /* Outputs */
5309  struct sqlite3_index_constraint_usage {
5310    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
5311    unsigned char omit;      /* Do not code a test for this constraint */
5312  } *aConstraintUsage;
5313  int idxNum;                /* Number used to identify the index */
5314  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
5315  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
5316  int orderByConsumed;       /* True if output is already ordered */
5317  double estimatedCost;      /* Estimated cost of using this index */
5318};
5319#define SQLITE_INDEX_CONSTRAINT_EQ    2
5320#define SQLITE_INDEX_CONSTRAINT_GT    4
5321#define SQLITE_INDEX_CONSTRAINT_LE    8
5322#define SQLITE_INDEX_CONSTRAINT_LT    16
5323#define SQLITE_INDEX_CONSTRAINT_GE    32
5324#define SQLITE_INDEX_CONSTRAINT_MATCH 64
5325
5326/*
5327** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400>
5328**
5329** This routine is used to register a new module name with a
5330** [database connection].  Module names must be registered before
5331** creating new virtual tables on the module, or before using
5332** preexisting virtual tables of the module.
5333**
5334** This interface is experimental and is subject to change or
5335** removal in future releases of SQLite.
5336*/
5337int sqlite3_create_module(
5338  sqlite3 *db,               /* SQLite connection to register module with */
5339  const char *zName,         /* Name of the module */
5340  const sqlite3_module *,    /* Methods for the module */
5341  void *                     /* Client data for xCreate/xConnect */
5342);
5343
5344/*
5345** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
5346**
5347** This routine is identical to the [sqlite3_create_module()] method above,
5348** except that it allows a destructor function to be specified. It is
5349** even more experimental than the rest of the virtual tables API.
5350*/
5351int sqlite3_create_module_v2(
5352  sqlite3 *db,               /* SQLite connection to register module with */
5353  const char *zName,         /* Name of the module */
5354  const sqlite3_module *,    /* Methods for the module */
5355  void *,                    /* Client data for xCreate/xConnect */
5356  void(*xDestroy)(void*)     /* Module destructor function */
5357);
5358
5359/*
5360** CAPI3REF: Virtual Table Instance Object {H18010} <S20400>
5361** KEYWORDS: sqlite3_vtab
5362**
5363** Every module implementation uses a subclass of the following structure
5364** to describe a particular instance of the module.  Each subclass will
5365** be tailored to the specific needs of the module implementation.
5366** The purpose of this superclass is to define certain fields that are
5367** common to all module implementations.
5368**
5369** Virtual tables methods can set an error message by assigning a
5370** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
5371** take care that any prior string is freed by a call to [sqlite3_free()]
5372** prior to assigning a new string to zErrMsg.  After the error message
5373** is delivered up to the client application, the string will be automatically
5374** freed by sqlite3_free() and the zErrMsg field will be zeroed.  Note
5375** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
5376** since virtual tables are commonly implemented in loadable extensions which
5377** do not have access to sqlite3MPrintf() or sqlite3Free().
5378**
5379** This interface is experimental and is subject to change or
5380** removal in future releases of SQLite.
5381*/
5382struct sqlite3_vtab {
5383  const sqlite3_module *pModule;  /* The module for this virtual table */
5384  int nRef;                       /* Used internally */
5385  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
5386  /* Virtual table implementations will typically add additional fields */
5387};
5388
5389/*
5390** CAPI3REF: Virtual Table Cursor Object  {H18020} <S20400>
5391** KEYWORDS: sqlite3_vtab_cursor
5392**
5393** Every module implementation uses a subclass of the following structure
5394** to describe cursors that point into the virtual table and are used
5395** to loop through the virtual table.  Cursors are created using the
5396** xOpen method of the module.  Each module implementation will define
5397** the content of a cursor structure to suit its own needs.
5398**
5399** This superclass exists in order to define fields of the cursor that
5400** are common to all implementations.
5401**
5402** This interface is experimental and is subject to change or
5403** removal in future releases of SQLite.
5404*/
5405struct sqlite3_vtab_cursor {
5406  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
5407  /* Virtual table implementations will typically add additional fields */
5408};
5409
5410/*
5411** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400>
5412**
5413** The xCreate and xConnect methods of a module use the following API
5414** to declare the format (the names and datatypes of the columns) of
5415** the virtual tables they implement.
5416**
5417** This interface is experimental and is subject to change or
5418** removal in future releases of SQLite.
5419*/
5420int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
5421
5422/*
5423** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
5424**
5425** Virtual tables can provide alternative implementations of functions
5426** using the xFindFunction method.  But global versions of those functions
5427** must exist in order to be overloaded.
5428**
5429** This API makes sure a global version of a function with a particular
5430** name and number of parameters exists.  If no such function exists
5431** before this API is called, a new function is created.  The implementation
5432** of the new function always causes an exception to be thrown.  So
5433** the new function is not good for anything by itself.  Its only
5434** purpose is to be a placeholder function that can be overloaded
5435** by virtual tables.
5436**
5437** This API should be considered part of the virtual table interface,
5438** which is experimental and subject to change.
5439*/
5440int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
5441
5442/*
5443** The interface to the virtual-table mechanism defined above (back up
5444** to a comment remarkably similar to this one) is currently considered
5445** to be experimental.  The interface might change in incompatible ways.
5446** If this is a problem for you, do not use the interface at this time.
5447**
5448** When the virtual-table mechanism stabilizes, we will declare the
5449** interface fixed, support it indefinitely, and remove this comment.
5450**
5451****** EXPERIMENTAL - subject to change without notice **************
5452*/
5453
5454/*
5455** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230>
5456** KEYWORDS: {BLOB handle} {BLOB handles}
5457**
5458** An instance of this object represents an open BLOB on which
5459** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
5460** Objects of this type are created by [sqlite3_blob_open()]
5461** and destroyed by [sqlite3_blob_close()].
5462** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
5463** can be used to read or write small subsections of the BLOB.
5464** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
5465*/
5466typedef struct sqlite3_blob sqlite3_blob;
5467
5468/*
5469** CAPI3REF: Open A BLOB For Incremental I/O {H17810} <S30230>
5470**
5471** This interfaces opens a [BLOB handle | handle] to the BLOB located
5472** in row iRow, column zColumn, table zTable in database zDb;
5473** in other words, the same BLOB that would be selected by:
5474**
5475** <pre>
5476**     SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
5477** </pre> {END}
5478**
5479** If the flags parameter is non-zero, the the BLOB is opened for read
5480** and write access. If it is zero, the BLOB is opened for read access.
5481**
5482** Note that the database name is not the filename that contains
5483** the database but rather the symbolic name of the database that
5484** is assigned when the database is connected using [ATTACH].
5485** For the main database file, the database name is "main".
5486** For TEMP tables, the database name is "temp".
5487**
5488** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
5489** to *ppBlob. Otherwise an [error code] is returned and any value written
5490** to *ppBlob should not be used by the caller.
5491** This function sets the [database connection] error code and message
5492** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
5493**
5494** If the row that a BLOB handle points to is modified by an
5495** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
5496** then the BLOB handle is marked as "expired".
5497** This is true if any column of the row is changed, even a column
5498** other than the one the BLOB handle is open on.
5499** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
5500** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
5501** Changes written into a BLOB prior to the BLOB expiring are not
5502** rollback by the expiration of the BLOB.  Such changes will eventually
5503** commit if the transaction continues to completion.
5504**
5505** INVARIANTS:
5506**
5507** {H17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
5508**          interface shall open an [sqlite3_blob] object P on the BLOB
5509**          in column C of the table T in the database B on
5510**          the [database connection] D.
5511**
5512** {H17814} A successful invocation of [sqlite3_blob_open(D,...)] shall start
5513**          a new transaction on the [database connection] D if that
5514**          connection is not already in a transaction.
5515**
5516** {H17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface shall open
5517**          the BLOB for read and write access if and only if the F
5518**          parameter is non-zero.
5519**
5520** {H17819} The [sqlite3_blob_open()] interface shall return [SQLITE_OK] on
5521**          success and an appropriate [error code] on failure.
5522**
5523** {H17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
5524**          then subsequent calls to [sqlite3_errcode(D)],
5525**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
5526**          information appropriate for that error.
5527**
5528** {H17824} If any column in the row that a [sqlite3_blob] has open is
5529**          changed by a separate [UPDATE] or [DELETE] statement or by
5530**          an [ON CONFLICT] side effect, then the [sqlite3_blob] shall
5531**          be marked as invalid.
5532*/
5533int sqlite3_blob_open(
5534  sqlite3*,
5535  const char *zDb,
5536  const char *zTable,
5537  const char *zColumn,
5538  sqlite3_int64 iRow,
5539  int flags,
5540  sqlite3_blob **ppBlob
5541);
5542
5543/*
5544** CAPI3REF: Close A BLOB Handle {H17830} <S30230>
5545**
5546** Closes an open [BLOB handle].
5547**
5548** Closing a BLOB shall cause the current transaction to commit
5549** if there are no other BLOBs, no pending prepared statements, and the
5550** database connection is in [autocommit mode].
5551** If any writes were made to the BLOB, they might be held in cache
5552** until the close operation if they will fit. {END}
5553**
5554** Closing the BLOB often forces the changes
5555** out to disk and so if any I/O errors occur, they will likely occur
5556** at the time when the BLOB is closed.  {H17833} Any errors that occur during
5557** closing are reported as a non-zero return value.
5558**
5559** The BLOB is closed unconditionally.  Even if this routine returns
5560** an error code, the BLOB is still closed.
5561**
5562** INVARIANTS:
5563**
5564** {H17833} The [sqlite3_blob_close(P)] interface closes an [sqlite3_blob]
5565**          object P previously opened using [sqlite3_blob_open()].
5566**
5567** {H17836} Closing an [sqlite3_blob] object using
5568**          [sqlite3_blob_close()] shall cause the current transaction to
5569**          commit if there are no other open [sqlite3_blob] objects
5570**          or [prepared statements] on the same [database connection] and
5571**          the database connection is in [autocommit mode].
5572**
5573** {H17839} The [sqlite3_blob_close(P)] interfaces shall close the
5574**          [sqlite3_blob] object P unconditionally, even if
5575**          [sqlite3_blob_close(P)] returns something other than [SQLITE_OK].
5576*/
5577int sqlite3_blob_close(sqlite3_blob *);
5578
5579/*
5580** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230>
5581**
5582** Returns the size in bytes of the BLOB accessible via the open
5583** []BLOB handle] in its only argument.
5584**
5585** INVARIANTS:
5586**
5587** {H17843} The [sqlite3_blob_bytes(P)] interface returns the size
5588**          in bytes of the BLOB that the [sqlite3_blob] object P
5589**          refers to.
5590*/
5591int sqlite3_blob_bytes(sqlite3_blob *);
5592
5593/*
5594** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230>
5595**
5596** This function is used to read data from an open [BLOB handle] into a
5597** caller-supplied buffer. N bytes of data are copied into buffer Z
5598** from the open BLOB, starting at offset iOffset.
5599**
5600** If offset iOffset is less than N bytes from the end of the BLOB,
5601** [SQLITE_ERROR] is returned and no data is read.  If N or iOffset is
5602** less than zero, [SQLITE_ERROR] is returned and no data is read.
5603**
5604** An attempt to read from an expired [BLOB handle] fails with an
5605** error code of [SQLITE_ABORT].
5606**
5607** On success, SQLITE_OK is returned.
5608** Otherwise, an [error code] or an [extended error code] is returned.
5609**
5610** INVARIANTS:
5611**
5612** {H17853} A successful invocation of [sqlite3_blob_read(P,Z,N,X)]
5613**          shall reads N bytes of data out of the BLOB referenced by
5614**          [BLOB handle] P beginning at offset X and store those bytes
5615**          into buffer Z.
5616**
5617** {H17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the BLOB
5618**          is less than N+X bytes, then the function shall leave the
5619**          Z buffer unchanged and return [SQLITE_ERROR].
5620**
5621** {H17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
5622**          then the function shall leave the Z buffer unchanged
5623**          and return [SQLITE_ERROR].
5624**
5625** {H17862} The [sqlite3_blob_read(P,Z,N,X)] interface shall return [SQLITE_OK]
5626**          if N bytes are successfully read into buffer Z.
5627**
5628** {H17863} If the [BLOB handle] P is expired and X and N are within bounds
5629**          then [sqlite3_blob_read(P,Z,N,X)] shall leave the Z buffer
5630**          unchanged and return [SQLITE_ABORT].
5631**
5632** {H17865} If the requested read could not be completed,
5633**          the [sqlite3_blob_read(P,Z,N,X)] interface shall return an
5634**          appropriate [error code] or [extended error code].
5635**
5636** {H17868} If an error occurs during evaluation of [sqlite3_blob_read(P,...)]
5637**          then subsequent calls to [sqlite3_errcode(D)],
5638**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
5639**          information appropriate for that error, where D is the
5640**          [database connection] that was used to open the [BLOB handle] P.
5641*/
5642int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
5643
5644/*
5645** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230>
5646**
5647** This function is used to write data into an open [BLOB handle] from a
5648** caller-supplied buffer. N bytes of data are copied from the buffer Z
5649** into the open BLOB, starting at offset iOffset.
5650**
5651** If the [BLOB handle] passed as the first argument was not opened for
5652** writing (the flags parameter to [sqlite3_blob_open()] was zero),
5653** this function returns [SQLITE_READONLY].
5654**
5655** This function may only modify the contents of the BLOB; it is
5656** not possible to increase the size of a BLOB using this API.
5657** If offset iOffset is less than N bytes from the end of the BLOB,
5658** [SQLITE_ERROR] is returned and no data is written.  If N is
5659** less than zero [SQLITE_ERROR] is returned and no data is written.
5660**
5661** An attempt to write to an expired [BLOB handle] fails with an
5662** error code of [SQLITE_ABORT].  Writes to the BLOB that occurred
5663** before the [BLOB handle] expired are not rolled back by the
5664** expiration of the handle, though of course those changes might
5665** have been overwritten by the statement that expired the BLOB handle
5666** or by other independent statements.
5667**
5668** On success, SQLITE_OK is returned.
5669** Otherwise, an  [error code] or an [extended error code] is returned.
5670**
5671** INVARIANTS:
5672**
5673** {H17873} A successful invocation of [sqlite3_blob_write(P,Z,N,X)]
5674**          shall write N bytes of data from buffer Z into the BLOB
5675**          referenced by [BLOB handle] P beginning at offset X into
5676**          the BLOB.
5677**
5678** {H17874} In the absence of other overridding changes, the changes
5679**          written to a BLOB by [sqlite3_blob_write()] shall
5680**          remain in effect after the associated [BLOB handle] expires.
5681**
5682** {H17875} If the [BLOB handle] P was opened for reading only then
5683**          an invocation of [sqlite3_blob_write(P,Z,N,X)] shall leave
5684**          the referenced BLOB unchanged and return [SQLITE_READONLY].
5685**
5686** {H17876} If the size of the BLOB referenced by [BLOB handle] P is
5687**          less than N+X bytes then [sqlite3_blob_write(P,Z,N,X)] shall
5688**          leave the BLOB unchanged and return [SQLITE_ERROR].
5689**
5690** {H17877} If the [BLOB handle] P is expired and X and N are within bounds
5691**          then [sqlite3_blob_read(P,Z,N,X)] shall leave the BLOB
5692**          unchanged and return [SQLITE_ABORT].
5693**
5694** {H17879} If X or N are less than zero then [sqlite3_blob_write(P,Z,N,X)]
5695**          shall leave the BLOB referenced by [BLOB handle] P unchanged
5696**          and return [SQLITE_ERROR].
5697**
5698** {H17882} The [sqlite3_blob_write(P,Z,N,X)] interface shall return
5699**          [SQLITE_OK] if N bytes where successfully written into the BLOB.
5700**
5701** {H17885} If the requested write could not be completed,
5702**          the [sqlite3_blob_write(P,Z,N,X)] interface shall return an
5703**          appropriate [error code] or [extended error code].
5704**
5705** {H17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
5706**          then subsequent calls to [sqlite3_errcode(D)],
5707**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
5708**          information appropriate for that error.
5709*/
5710int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
5711
5712/*
5713** CAPI3REF: Virtual File System Objects {H11200} <S20100>
5714**
5715** A virtual filesystem (VFS) is an [sqlite3_vfs] object
5716** that SQLite uses to interact
5717** with the underlying operating system.  Most SQLite builds come with a
5718** single default VFS that is appropriate for the host computer.
5719** New VFSes can be registered and existing VFSes can be unregistered.
5720** The following interfaces are provided.
5721**
5722** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
5723** Names are case sensitive.
5724** Names are zero-terminated UTF-8 strings.
5725** If there is no match, a NULL pointer is returned.
5726** If zVfsName is NULL then the default VFS is returned.
5727**
5728** New VFSes are registered with sqlite3_vfs_register().
5729** Each new VFS becomes the default VFS if the makeDflt flag is set.
5730** The same VFS can be registered multiple times without injury.
5731** To make an existing VFS into the default VFS, register it again
5732** with the makeDflt flag set.  If two different VFSes with the
5733** same name are registered, the behavior is undefined.  If a
5734** VFS is registered with a name that is NULL or an empty string,
5735** then the behavior is undefined.
5736**
5737** Unregister a VFS with the sqlite3_vfs_unregister() interface.
5738** If the default VFS is unregistered, another VFS is chosen as
5739** the default.  The choice for the new VFS is arbitrary.
5740**
5741** INVARIANTS:
5742**
5743** {H11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
5744**          registered [sqlite3_vfs] object whose name exactly matches
5745**          the zero-terminated UTF-8 string N, or it returns NULL if
5746**          there is no match.
5747**
5748** {H11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
5749**          the function returns a pointer to the default [sqlite3_vfs]
5750**          object if there is one, or NULL if there is no default
5751**          [sqlite3_vfs] object.
5752**
5753** {H11209} The [sqlite3_vfs_register(P,F)] interface registers the
5754**          well-formed [sqlite3_vfs] object P using the name given
5755**          by the zName field of the object.
5756**
5757** {H11212} Using the [sqlite3_vfs_register(P,F)] interface to register
5758**          the same [sqlite3_vfs] object multiple times is a harmless no-op.
5759**
5760** {H11215} The [sqlite3_vfs_register(P,F)] interface makes the [sqlite3_vfs]
5761**          object P the default [sqlite3_vfs] object if F is non-zero.
5762**
5763** {H11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
5764**          [sqlite3_vfs] object P so that it is no longer returned by
5765**          subsequent calls to [sqlite3_vfs_find()].
5766*/
5767sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
5768int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
5769int sqlite3_vfs_unregister(sqlite3_vfs*);
5770
5771/*
5772** CAPI3REF: Mutexes {H17000} <S20000>
5773**
5774** The SQLite core uses these routines for thread
5775** synchronization. Though they are intended for internal
5776** use by SQLite, code that links against SQLite is
5777** permitted to use any of these routines.
5778**
5779** The SQLite source code contains multiple implementations
5780** of these mutex routines.  An appropriate implementation
5781** is selected automatically at compile-time.  The following
5782** implementations are available in the SQLite core:
5783**
5784** <ul>
5785** <li>   SQLITE_MUTEX_OS2
5786** <li>   SQLITE_MUTEX_PTHREAD
5787** <li>   SQLITE_MUTEX_W32
5788** <li>   SQLITE_MUTEX_NOOP
5789** </ul>
5790**
5791** The SQLITE_MUTEX_NOOP implementation is a set of routines
5792** that does no real locking and is appropriate for use in
5793** a single-threaded application.  The SQLITE_MUTEX_OS2,
5794** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
5795** are appropriate for use on OS/2, Unix, and Windows.
5796**
5797** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
5798** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
5799** implementation is included with the library. In this case the
5800** application must supply a custom mutex implementation using the
5801** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
5802** before calling sqlite3_initialize() or any other public sqlite3_
5803** function that calls sqlite3_initialize().
5804**
5805** {H17011} The sqlite3_mutex_alloc() routine allocates a new
5806** mutex and returns a pointer to it. {H17012} If it returns NULL
5807** that means that a mutex could not be allocated. {H17013} SQLite
5808** will unwind its stack and return an error. {H17014} The argument
5809** to sqlite3_mutex_alloc() is one of these integer constants:
5810**
5811** <ul>
5812** <li>  SQLITE_MUTEX_FAST
5813** <li>  SQLITE_MUTEX_RECURSIVE
5814** <li>  SQLITE_MUTEX_STATIC_MASTER
5815** <li>  SQLITE_MUTEX_STATIC_MEM
5816** <li>  SQLITE_MUTEX_STATIC_MEM2
5817** <li>  SQLITE_MUTEX_STATIC_PRNG
5818** <li>  SQLITE_MUTEX_STATIC_LRU
5819** <li>  SQLITE_MUTEX_STATIC_LRU2
5820** </ul>
5821**
5822** {H17015} The first two constants cause sqlite3_mutex_alloc() to create
5823** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
5824** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END}
5825** The mutex implementation does not need to make a distinction
5826** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
5827** not want to.  {H17016} But SQLite will only request a recursive mutex in
5828** cases where it really needs one.  {END} If a faster non-recursive mutex
5829** implementation is available on the host platform, the mutex subsystem
5830** might return such a mutex in response to SQLITE_MUTEX_FAST.
5831**
5832** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
5833** a pointer to a static preexisting mutex. {END}  Four static mutexes are
5834** used by the current version of SQLite.  Future versions of SQLite
5835** may add additional static mutexes.  Static mutexes are for internal
5836** use by SQLite only.  Applications that use SQLite mutexes should
5837** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
5838** SQLITE_MUTEX_RECURSIVE.
5839**
5840** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
5841** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
5842** returns a different mutex on every call.  {H17034} But for the static
5843** mutex types, the same mutex is returned on every call that has
5844** the same type number.
5845**
5846** {H17019} The sqlite3_mutex_free() routine deallocates a previously
5847** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every
5848** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in
5849** use when they are deallocated. {A17022} Attempting to deallocate a static
5850** mutex results in undefined behavior. {H17023} SQLite never deallocates
5851** a static mutex. {END}
5852**
5853** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
5854** to enter a mutex. {H17024} If another thread is already within the mutex,
5855** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
5856** SQLITE_BUSY. {H17025}  The sqlite3_mutex_try() interface returns [SQLITE_OK]
5857** upon successful entry.  {H17026} Mutexes created using
5858** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
5859** {H17027} In such cases the,
5860** mutex must be exited an equal number of times before another thread
5861** can enter.  {A17028} If the same thread tries to enter any other
5862** kind of mutex more than once, the behavior is undefined.
5863** {H17029} SQLite will never exhibit
5864** such behavior in its own use of mutexes.
5865**
5866** Some systems (for example, Windows 95) do not support the operation
5867** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
5868** will always return SQLITE_BUSY.  {H17030} The SQLite core only ever uses
5869** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
5870**
5871** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was
5872** previously entered by the same thread.  {A17032} The behavior
5873** is undefined if the mutex is not currently entered by the
5874** calling thread or is not currently allocated.  {H17033} SQLite will
5875** never do either. {END}
5876**
5877** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
5878** sqlite3_mutex_leave() is a NULL pointer, then all three routines
5879** behave as no-ops.
5880**
5881** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
5882*/
5883sqlite3_mutex *sqlite3_mutex_alloc(int);
5884void sqlite3_mutex_free(sqlite3_mutex*);
5885void sqlite3_mutex_enter(sqlite3_mutex*);
5886int sqlite3_mutex_try(sqlite3_mutex*);
5887void sqlite3_mutex_leave(sqlite3_mutex*);
5888
5889/*
5890** CAPI3REF: Mutex Methods Object {H17120} <S20130>
5891**
5892** An instance of this structure defines the low-level routines
5893** used to allocate and use mutexes.
5894**
5895** Usually, the default mutex implementations provided by SQLite are
5896** sufficient, however the user has the option of substituting a custom
5897** implementation for specialized deployments or systems for which SQLite
5898** does not provide a suitable implementation. In this case, the user
5899** creates and populates an instance of this structure to pass
5900** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
5901** Additionally, an instance of this structure can be used as an
5902** output variable when querying the system for the current mutex
5903** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
5904**
5905** The xMutexInit method defined by this structure is invoked as
5906** part of system initialization by the sqlite3_initialize() function.
5907** {H17001} The xMutexInit routine shall be called by SQLite once for each
5908** effective call to [sqlite3_initialize()].
5909**
5910** The xMutexEnd method defined by this structure is invoked as
5911** part of system shutdown by the sqlite3_shutdown() function. The
5912** implementation of this method is expected to release all outstanding
5913** resources obtained by the mutex methods implementation, especially
5914** those obtained by the xMutexInit method. {H17003} The xMutexEnd()
5915** interface shall be invoked once for each call to [sqlite3_shutdown()].
5916**
5917** The remaining seven methods defined by this structure (xMutexAlloc,
5918** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
5919** xMutexNotheld) implement the following interfaces (respectively):
5920**
5921** <ul>
5922**   <li>  [sqlite3_mutex_alloc()] </li>
5923**   <li>  [sqlite3_mutex_free()] </li>
5924**   <li>  [sqlite3_mutex_enter()] </li>
5925**   <li>  [sqlite3_mutex_try()] </li>
5926**   <li>  [sqlite3_mutex_leave()] </li>
5927**   <li>  [sqlite3_mutex_held()] </li>
5928**   <li>  [sqlite3_mutex_notheld()] </li>
5929** </ul>
5930**
5931** The only difference is that the public sqlite3_XXX functions enumerated
5932** above silently ignore any invocations that pass a NULL pointer instead
5933** of a valid mutex handle. The implementations of the methods defined
5934** by this structure are not required to handle this case, the results
5935** of passing a NULL pointer instead of a valid mutex handle are undefined
5936** (i.e. it is acceptable to provide an implementation that segfaults if
5937** it is passed a NULL pointer).
5938*/
5939typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
5940struct sqlite3_mutex_methods {
5941  int (*xMutexInit)(void);
5942  int (*xMutexEnd)(void);
5943  sqlite3_mutex *(*xMutexAlloc)(int);
5944  void (*xMutexFree)(sqlite3_mutex *);
5945  void (*xMutexEnter)(sqlite3_mutex *);
5946  int (*xMutexTry)(sqlite3_mutex *);
5947  void (*xMutexLeave)(sqlite3_mutex *);
5948  int (*xMutexHeld)(sqlite3_mutex *);
5949  int (*xMutexNotheld)(sqlite3_mutex *);
5950};
5951
5952/*
5953** CAPI3REF: Mutex Verification Routines {H17080} <S20130> <S30800>
5954**
5955** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
5956** are intended for use inside assert() statements. {H17081} The SQLite core
5957** never uses these routines except inside an assert() and applications
5958** are advised to follow the lead of the core.  {H17082} The core only
5959** provides implementations for these routines when it is compiled
5960** with the SQLITE_DEBUG flag.  {A17087} External mutex implementations
5961** are only required to provide these routines if SQLITE_DEBUG is
5962** defined and if NDEBUG is not defined.
5963**
5964** {H17083} These routines should return true if the mutex in their argument
5965** is held or not held, respectively, by the calling thread.
5966**
5967** {X17084} The implementation is not required to provided versions of these
5968** routines that actually work. If the implementation does not provide working
5969** versions of these routines, it should at least provide stubs that always
5970** return true so that one does not get spurious assertion failures.
5971**
5972** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
5973** the routine should return 1.  {END} This seems counter-intuitive since
5974** clearly the mutex cannot be held if it does not exist.  But the
5975** the reason the mutex does not exist is because the build is not
5976** using mutexes.  And we do not want the assert() containing the
5977** call to sqlite3_mutex_held() to fail, so a non-zero return is
5978** the appropriate thing to do.  {H17086} The sqlite3_mutex_notheld()
5979** interface should also return 1 when given a NULL pointer.
5980*/
5981int sqlite3_mutex_held(sqlite3_mutex*);
5982int sqlite3_mutex_notheld(sqlite3_mutex*);
5983
5984/*
5985** CAPI3REF: Mutex Types {H17001} <H17000>
5986**
5987** {H17002} The [sqlite3_mutex_alloc()] interface takes a single argument
5988** which is one of these integer constants.
5989*/
5990#define SQLITE_MUTEX_FAST             0
5991#define SQLITE_MUTEX_RECURSIVE        1
5992#define SQLITE_MUTEX_STATIC_MASTER    2
5993#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
5994#define SQLITE_MUTEX_STATIC_MEM2      4  /* sqlite3_release_memory() */
5995#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
5996#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
5997#define SQLITE_MUTEX_STATIC_LRU2      7  /* lru page list */
5998
5999/*
6000** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800>
6001**
6002** {H11301} The [sqlite3_file_control()] interface makes a direct call to the
6003** xFileControl method for the [sqlite3_io_methods] object associated
6004** with a particular database identified by the second argument. {H11302} The
6005** name of the database is the name assigned to the database by the
6006** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
6007** database. {H11303} To control the main database file, use the name "main"
6008** or a NULL pointer. {H11304} The third and fourth parameters to this routine
6009** are passed directly through to the second and third parameters of
6010** the xFileControl method.  {H11305} The return value of the xFileControl
6011** method becomes the return value of this routine.
6012**
6013** {H11306} If the second parameter (zDbName) does not match the name of any
6014** open database file, then SQLITE_ERROR is returned. {H11307} This error
6015** code is not remembered and will not be recalled by [sqlite3_errcode()]
6016** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
6017** also return SQLITE_ERROR.  {A11309} There is no way to distinguish between
6018** an incorrect zDbName and an SQLITE_ERROR return from the underlying
6019** xFileControl method. {END}
6020**
6021** See also: [SQLITE_FCNTL_LOCKSTATE]
6022*/
6023int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
6024
6025/*
6026** CAPI3REF: Testing Interface {H11400} <S30800>
6027**
6028** The sqlite3_test_control() interface is used to read out internal
6029** state of SQLite and to inject faults into SQLite for testing
6030** purposes.  The first parameter is an operation code that determines
6031** the number, meaning, and operation of all subsequent parameters.
6032**
6033** This interface is not for use by applications.  It exists solely
6034** for verifying the correct operation of the SQLite library.  Depending
6035** on how the SQLite library is compiled, this interface might not exist.
6036**
6037** The details of the operation codes, their meanings, the parameters
6038** they take, and what they do are all subject to change without notice.
6039** Unlike most of the SQLite API, this function is not guaranteed to
6040** operate consistently from one release to the next.
6041*/
6042int sqlite3_test_control(int op, ...);
6043
6044/*
6045** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400>
6046**
6047** These constants are the valid operation code parameters used
6048** as the first argument to [sqlite3_test_control()].
6049**
6050** These parameters and their meanings are subject to change
6051** without notice.  These values are for testing purposes only.
6052** Applications should not use any of these parameters or the
6053** [sqlite3_test_control()] interface.
6054*/
6055#define SQLITE_TESTCTRL_PRNG_SAVE                5
6056#define SQLITE_TESTCTRL_PRNG_RESTORE             6
6057#define SQLITE_TESTCTRL_PRNG_RESET               7
6058#define SQLITE_TESTCTRL_BITVEC_TEST              8
6059#define SQLITE_TESTCTRL_FAULT_INSTALL            9
6060#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
6061
6062/*
6063** CAPI3REF: SQLite Runtime Status {H17200} <S60200>
6064**
6065** This interface is used to retrieve runtime status information
6066** about the preformance of SQLite, and optionally to reset various
6067** highwater marks.  The first argument is an integer code for
6068** the specific parameter to measure.  Recognized integer codes
6069** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].
6070** The current value of the parameter is returned into *pCurrent.
6071** The highest recorded value is returned in *pHighwater.  If the
6072** resetFlag is true, then the highest record value is reset after
6073** *pHighwater is written. Some parameters do not record the highest
6074** value.  For those parameters
6075** nothing is written into *pHighwater and the resetFlag is ignored.
6076** Other parameters record only the highwater mark and not the current
6077** value.  For these latter parameters nothing is written into *pCurrent.
6078**
6079** This routine returns SQLITE_OK on success and a non-zero
6080** [error code] on failure.
6081**
6082** This routine is threadsafe but is not atomic.  This routine can
6083** called while other threads are running the same or different SQLite
6084** interfaces.  However the values returned in *pCurrent and
6085** *pHighwater reflect the status of SQLite at different points in time
6086** and it is possible that another thread might change the parameter
6087** in between the times when *pCurrent and *pHighwater are written.
6088**
6089** This interface is experimental and is subject to change or
6090** removal in future releases of SQLite.
6091*/
6092int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
6093int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
6094
6095/*
6096** CAPI3REF: Status Parameters {H17250} <H17200>
6097**
6098** These integer constants designate various run-time status parameters
6099** that can be returned by [sqlite3_status()].
6100**
6101** <dl>
6102** <dt>SQLITE_STATUS_MEMORY_USED</dt>
6103** <dd>This parameter is the current amount of memory checked out
6104** using [sqlite3_malloc()], either directly or indirectly.  The
6105** figure includes calls made to [sqlite3_malloc()] by the application
6106** and internal memory usage by the SQLite library.  Scratch memory
6107** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
6108** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
6109** this parameter.  The amount returned is the sum of the allocation
6110** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>
6111**
6112** <dt>SQLITE_STATUS_PAGECACHE_USED</dt>
6113** <dd>This parameter returns the number of pages used out of the
6114** page cache buffer configured using [SQLITE_CONFIG_PAGECACHE].  The
6115** value returned is in pages, not in bytes.</dd>
6116**
6117** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
6118** <dd>This parameter returns the number of bytes of page cache
6119** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
6120** buffer and where forced to overflow to [sqlite3_malloc()].</dd>
6121**
6122** <dt>SQLITE_STATUS_SCRATCH_USED</dt>
6123** <dd>This parameter returns the number of allocations used out of the
6124** scratch allocation lookaside buffer configured using
6125** [SQLITE_CONFIG_SCRATCH].  The value returned is in allocations, not
6126** in bytes.  Since a single thread may only have one allocation
6127** outstanding at time, this parameter also reports the number of threads
6128** using scratch memory at the same time.</dd>
6129**
6130** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
6131** <dd>This parameter returns the number of bytes of scratch memory
6132** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
6133** buffer and where forced to overflow to [sqlite3_malloc()].</dd>
6134**
6135** <dt>SQLITE_STATUS_MALLOC_SIZE</dt>
6136** <dd>This parameter records the largest memory allocation request
6137** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
6138** internal equivalents).  The value of interest is return in the
6139** *pHighwater parameter to [sqlite3_status()].  The value written
6140** into the *pCurrent parameter is undefined.</dd>
6141**
6142** <dt>SQLITE_STATUS_PARSER_STACK</dt>
6143** <dd>This parameter records the deepest parser stack.  It is only
6144** meaningful if SQLite is compiled with YYTRACKMAXSTACKDEPTH.</dd>
6145** </dl>
6146**
6147** New status parameters may be added from time to time.
6148*/
6149#define SQLITE_STATUS_MEMORY_USED          0
6150#define SQLITE_STATUS_PAGECACHE_USED       1
6151#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
6152#define SQLITE_STATUS_SCRATCH_USED         3
6153#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
6154#define SQLITE_STATUS_MALLOC_SIZE          5
6155#define SQLITE_STATUS_PARSER_STACK         6
6156
6157/*
6158** CAPI3REF: Status Parameters for database connections {H17275} <H17200>
6159**
6160** Status verbs for [sqlite3_db_status()].
6161**
6162** <dl>
6163** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
6164** <dd>This parameter returns the number of lookaside memory slots currently
6165** checked out.</dd>
6166** </dl>
6167*/
6168#define SQLITE_DBSTATUS_LOOKASIDE_USED     0
6169
6170/*
6171** Undo the hack that converts floating point types to integer for
6172** builds on processors without floating point support.
6173*/
6174#ifdef SQLITE_OMIT_FLOATING_POINT
6175# undef double
6176#endif
6177
6178#ifdef __cplusplus
6179}  /* End of the 'extern "C"' block */
6180#endif
6181#endif
6182