xref: /sqlite-3.40.0/src/sqliteInt.h (revision fee981e5)
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 ** Internal interface definitions for SQLite.
13 **
14 */
15 #ifndef _SQLITEINT_H_
16 #define _SQLITEINT_H_
17 
18 /*
19 ** Include the header file used to customize the compiler options for MSVC.
20 ** This should be done first so that it can successfully prevent spurious
21 ** compiler warnings due to subsequent content in this file and other files
22 ** that are included by this file.
23 */
24 #include "msvc.h"
25 
26 /*
27 ** Special setup for VxWorks
28 */
29 #include "vxworks.h"
30 
31 /*
32 ** These #defines should enable >2GB file support on POSIX if the
33 ** underlying operating system supports it.  If the OS lacks
34 ** large file support, or if the OS is windows, these should be no-ops.
35 **
36 ** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
37 ** system #includes.  Hence, this block of code must be the very first
38 ** code in all source files.
39 **
40 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
41 ** on the compiler command line.  This is necessary if you are compiling
42 ** on a recent machine (ex: Red Hat 7.2) but you want your code to work
43 ** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
44 ** without this option, LFS is enable.  But LFS does not exist in the kernel
45 ** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
46 ** portability you should omit LFS.
47 **
48 ** The previous paragraph was written in 2005.  (This paragraph is written
49 ** on 2008-11-28.) These days, all Linux kernels support large files, so
50 ** you should probably leave LFS enabled.  But some embedded platforms might
51 ** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
52 **
53 ** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
54 */
55 #ifndef SQLITE_DISABLE_LFS
56 # define _LARGE_FILE       1
57 # ifndef _FILE_OFFSET_BITS
58 #   define _FILE_OFFSET_BITS 64
59 # endif
60 # define _LARGEFILE_SOURCE 1
61 #endif
62 
63 /* What version of GCC is being used.  0 means GCC is not being used */
64 #ifdef __GNUC__
65 # define GCC_VERSION (__GNUC__*1000000+__GNUC_MINOR__*1000+__GNUC_PATCHLEVEL__)
66 #else
67 # define GCC_VERSION 0
68 #endif
69 
70 /* Needed for various definitions... */
71 #if defined(__GNUC__) && !defined(_GNU_SOURCE)
72 # define _GNU_SOURCE
73 #endif
74 
75 #if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
76 # define _BSD_SOURCE
77 #endif
78 
79 /*
80 ** For MinGW, check to see if we can include the header file containing its
81 ** version information, among other things.  Normally, this internal MinGW
82 ** header file would [only] be included automatically by other MinGW header
83 ** files; however, the contained version information is now required by this
84 ** header file to work around binary compatibility issues (see below) and
85 ** this is the only known way to reliably obtain it.  This entire #if block
86 ** would be completely unnecessary if there was any other way of detecting
87 ** MinGW via their preprocessor (e.g. if they customized their GCC to define
88 ** some MinGW-specific macros).  When compiling for MinGW, either the
89 ** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
90 ** defined; otherwise, detection of conditions specific to MinGW will be
91 ** disabled.
92 */
93 #if defined(_HAVE_MINGW_H)
94 # include "mingw.h"
95 #elif defined(_HAVE__MINGW_H)
96 # include "_mingw.h"
97 #endif
98 
99 /*
100 ** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
101 ** define is required to maintain binary compatibility with the MSVC runtime
102 ** library in use (e.g. for Windows XP).
103 */
104 #if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
105     defined(_WIN32) && !defined(_WIN64) && \
106     defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
107     defined(__MSVCRT__)
108 # define _USE_32BIT_TIME_T
109 #endif
110 
111 /* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
112 ** first in QNX.  Also, the _USE_32BIT_TIME_T macro must appear first for
113 ** MinGW.
114 */
115 #include "sqlite3.h"
116 
117 /*
118 ** Include the configuration header output by 'configure' if we're using the
119 ** autoconf-based build
120 */
121 #ifdef _HAVE_SQLITE_CONFIG_H
122 #include "config.h"
123 #endif
124 
125 #include "sqliteLimit.h"
126 
127 /* Disable nuisance warnings on Borland compilers */
128 #if defined(__BORLANDC__)
129 #pragma warn -rch /* unreachable code */
130 #pragma warn -ccc /* Condition is always true or false */
131 #pragma warn -aus /* Assigned value is never used */
132 #pragma warn -csu /* Comparing signed and unsigned */
133 #pragma warn -spa /* Suspicious pointer arithmetic */
134 #endif
135 
136 /*
137 ** Include standard header files as necessary
138 */
139 #ifdef HAVE_STDINT_H
140 #include <stdint.h>
141 #endif
142 #ifdef HAVE_INTTYPES_H
143 #include <inttypes.h>
144 #endif
145 
146 /*
147 ** The following macros are used to cast pointers to integers and
148 ** integers to pointers.  The way you do this varies from one compiler
149 ** to the next, so we have developed the following set of #if statements
150 ** to generate appropriate macros for a wide range of compilers.
151 **
152 ** The correct "ANSI" way to do this is to use the intptr_t type.
153 ** Unfortunately, that typedef is not available on all compilers, or
154 ** if it is available, it requires an #include of specific headers
155 ** that vary from one machine to the next.
156 **
157 ** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
158 ** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
159 ** So we have to define the macros in different ways depending on the
160 ** compiler.
161 */
162 #if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
163 # define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
164 # define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
165 #elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
166 # define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
167 # define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
168 #elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
169 # define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
170 # define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
171 #else                          /* Generates a warning - but it always works */
172 # define SQLITE_INT_TO_PTR(X)  ((void*)(X))
173 # define SQLITE_PTR_TO_INT(X)  ((int)(X))
174 #endif
175 
176 /*
177 ** The SQLITE_WITHIN(P,S,E) macro checks to see if pointer P points to
178 ** something between S (inclusive) and E (exclusive).
179 **
180 ** In other words, S is a buffer and E is a pointer to the first byte after
181 ** the end of buffer S.  This macro returns true if P points to something
182 ** contained within the buffer S.
183 */
184 #if defined(HAVE_STDINT_H)
185 # define SQLITE_WITHIN(P,S,E) \
186     ((uintptr_t)(P)>=(uintptr_t)(S) && (uintptr_t)(P)<(uintptr_t)(E))
187 #else
188 # define SQLITE_WITHIN(P,S,E) ((P)>=(S) && (P)<(E))
189 #endif
190 
191 /*
192 ** A macro to hint to the compiler that a function should not be
193 ** inlined.
194 */
195 #if defined(__GNUC__)
196 #  define SQLITE_NOINLINE  __attribute__((noinline))
197 #elif defined(_MSC_VER) && _MSC_VER>=1310
198 #  define SQLITE_NOINLINE  __declspec(noinline)
199 #else
200 #  define SQLITE_NOINLINE
201 #endif
202 
203 /*
204 ** Make sure that the compiler intrinsics we desire are enabled when
205 ** compiling with an appropriate version of MSVC unless prevented by
206 ** the SQLITE_DISABLE_INTRINSIC define.
207 */
208 #if !defined(SQLITE_DISABLE_INTRINSIC)
209 #  if defined(_MSC_VER) && _MSC_VER>=1300
210 #    if !defined(_WIN32_WCE)
211 #      include <intrin.h>
212 #      pragma intrinsic(_byteswap_ushort)
213 #      pragma intrinsic(_byteswap_ulong)
214 #      pragma intrinsic(_ReadWriteBarrier)
215 #    else
216 #      include <cmnintrin.h>
217 #    endif
218 #  endif
219 #endif
220 
221 /*
222 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
223 ** 0 means mutexes are permanently disable and the library is never
224 ** threadsafe.  1 means the library is serialized which is the highest
225 ** level of threadsafety.  2 means the library is multithreaded - multiple
226 ** threads can use SQLite as long as no two threads try to use the same
227 ** database connection at the same time.
228 **
229 ** Older versions of SQLite used an optional THREADSAFE macro.
230 ** We support that for legacy.
231 */
232 #if !defined(SQLITE_THREADSAFE)
233 # if defined(THREADSAFE)
234 #   define SQLITE_THREADSAFE THREADSAFE
235 # else
236 #   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
237 # endif
238 #endif
239 
240 /*
241 ** Powersafe overwrite is on by default.  But can be turned off using
242 ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
243 */
244 #ifndef SQLITE_POWERSAFE_OVERWRITE
245 # define SQLITE_POWERSAFE_OVERWRITE 1
246 #endif
247 
248 /*
249 ** EVIDENCE-OF: R-25715-37072 Memory allocation statistics are enabled by
250 ** default unless SQLite is compiled with SQLITE_DEFAULT_MEMSTATUS=0 in
251 ** which case memory allocation statistics are disabled by default.
252 */
253 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
254 # define SQLITE_DEFAULT_MEMSTATUS 1
255 #endif
256 
257 /*
258 ** Exactly one of the following macros must be defined in order to
259 ** specify which memory allocation subsystem to use.
260 **
261 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
262 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
263 **     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
264 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
265 **
266 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
267 ** assert() macro is enabled, each call into the Win32 native heap subsystem
268 ** will cause HeapValidate to be called.  If heap validation should fail, an
269 ** assertion will be triggered.
270 **
271 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
272 ** the default.
273 */
274 #if defined(SQLITE_SYSTEM_MALLOC) \
275   + defined(SQLITE_WIN32_MALLOC) \
276   + defined(SQLITE_ZERO_MALLOC) \
277   + defined(SQLITE_MEMDEBUG)>1
278 # error "Two or more of the following compile-time configuration options\
279  are defined but at most one is allowed:\
280  SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
281  SQLITE_ZERO_MALLOC"
282 #endif
283 #if defined(SQLITE_SYSTEM_MALLOC) \
284   + defined(SQLITE_WIN32_MALLOC) \
285   + defined(SQLITE_ZERO_MALLOC) \
286   + defined(SQLITE_MEMDEBUG)==0
287 # define SQLITE_SYSTEM_MALLOC 1
288 #endif
289 
290 /*
291 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
292 ** sizes of memory allocations below this value where possible.
293 */
294 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
295 # define SQLITE_MALLOC_SOFT_LIMIT 1024
296 #endif
297 
298 /*
299 ** We need to define _XOPEN_SOURCE as follows in order to enable
300 ** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
301 ** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
302 ** it.
303 */
304 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
305 #  define _XOPEN_SOURCE 600
306 #endif
307 
308 /*
309 ** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
310 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
311 ** make it true by defining or undefining NDEBUG.
312 **
313 ** Setting NDEBUG makes the code smaller and faster by disabling the
314 ** assert() statements in the code.  So we want the default action
315 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
316 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
317 ** feature.
318 */
319 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
320 # define NDEBUG 1
321 #endif
322 #if defined(NDEBUG) && defined(SQLITE_DEBUG)
323 # undef NDEBUG
324 #endif
325 
326 /*
327 ** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
328 */
329 #if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
330 # define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
331 #endif
332 
333 /*
334 ** The testcase() macro is used to aid in coverage testing.  When
335 ** doing coverage testing, the condition inside the argument to
336 ** testcase() must be evaluated both true and false in order to
337 ** get full branch coverage.  The testcase() macro is inserted
338 ** to help ensure adequate test coverage in places where simple
339 ** condition/decision coverage is inadequate.  For example, testcase()
340 ** can be used to make sure boundary values are tested.  For
341 ** bitmask tests, testcase() can be used to make sure each bit
342 ** is significant and used at least once.  On switch statements
343 ** where multiple cases go to the same block of code, testcase()
344 ** can insure that all cases are evaluated.
345 **
346 */
347 #ifdef SQLITE_COVERAGE_TEST
348   void sqlite3Coverage(int);
349 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
350 #else
351 # define testcase(X)
352 #endif
353 
354 /*
355 ** The TESTONLY macro is used to enclose variable declarations or
356 ** other bits of code that are needed to support the arguments
357 ** within testcase() and assert() macros.
358 */
359 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
360 # define TESTONLY(X)  X
361 #else
362 # define TESTONLY(X)
363 #endif
364 
365 /*
366 ** Sometimes we need a small amount of code such as a variable initialization
367 ** to setup for a later assert() statement.  We do not want this code to
368 ** appear when assert() is disabled.  The following macro is therefore
369 ** used to contain that setup code.  The "VVA" acronym stands for
370 ** "Verification, Validation, and Accreditation".  In other words, the
371 ** code within VVA_ONLY() will only run during verification processes.
372 */
373 #ifndef NDEBUG
374 # define VVA_ONLY(X)  X
375 #else
376 # define VVA_ONLY(X)
377 #endif
378 
379 /*
380 ** The ALWAYS and NEVER macros surround boolean expressions which
381 ** are intended to always be true or false, respectively.  Such
382 ** expressions could be omitted from the code completely.  But they
383 ** are included in a few cases in order to enhance the resilience
384 ** of SQLite to unexpected behavior - to make the code "self-healing"
385 ** or "ductile" rather than being "brittle" and crashing at the first
386 ** hint of unplanned behavior.
387 **
388 ** In other words, ALWAYS and NEVER are added for defensive code.
389 **
390 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
391 ** be true and false so that the unreachable code they specify will
392 ** not be counted as untested code.
393 */
394 #if defined(SQLITE_COVERAGE_TEST)
395 # define ALWAYS(X)      (1)
396 # define NEVER(X)       (0)
397 #elif !defined(NDEBUG)
398 # define ALWAYS(X)      ((X)?1:(assert(0),0))
399 # define NEVER(X)       ((X)?(assert(0),1):0)
400 #else
401 # define ALWAYS(X)      (X)
402 # define NEVER(X)       (X)
403 #endif
404 
405 /*
406 ** Some malloc failures are only possible if SQLITE_TEST_REALLOC_STRESS is
407 ** defined.  We need to defend against those failures when testing with
408 ** SQLITE_TEST_REALLOC_STRESS, but we don't want the unreachable branches
409 ** during a normal build.  The following macro can be used to disable tests
410 ** that are always false except when SQLITE_TEST_REALLOC_STRESS is set.
411 */
412 #if defined(SQLITE_TEST_REALLOC_STRESS)
413 # define ONLY_IF_REALLOC_STRESS(X)  (X)
414 #elif !defined(NDEBUG)
415 # define ONLY_IF_REALLOC_STRESS(X)  ((X)?(assert(0),1):0)
416 #else
417 # define ONLY_IF_REALLOC_STRESS(X)  (0)
418 #endif
419 
420 /*
421 ** Declarations used for tracing the operating system interfaces.
422 */
423 #if defined(SQLITE_FORCE_OS_TRACE) || defined(SQLITE_TEST) || \
424     (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
425   extern int sqlite3OSTrace;
426 # define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
427 # define SQLITE_HAVE_OS_TRACE
428 #else
429 # define OSTRACE(X)
430 # undef  SQLITE_HAVE_OS_TRACE
431 #endif
432 
433 /*
434 ** Is the sqlite3ErrName() function needed in the build?  Currently,
435 ** it is needed by "mutex_w32.c" (when debugging), "os_win.c" (when
436 ** OSTRACE is enabled), and by several "test*.c" files (which are
437 ** compiled using SQLITE_TEST).
438 */
439 #if defined(SQLITE_HAVE_OS_TRACE) || defined(SQLITE_TEST) || \
440     (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
441 # define SQLITE_NEED_ERR_NAME
442 #else
443 # undef  SQLITE_NEED_ERR_NAME
444 #endif
445 
446 /*
447 ** Return true (non-zero) if the input is an integer that is too large
448 ** to fit in 32-bits.  This macro is used inside of various testcase()
449 ** macros to verify that we have tested SQLite for large-file support.
450 */
451 #define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
452 
453 /*
454 ** The macro unlikely() is a hint that surrounds a boolean
455 ** expression that is usually false.  Macro likely() surrounds
456 ** a boolean expression that is usually true.  These hints could,
457 ** in theory, be used by the compiler to generate better code, but
458 ** currently they are just comments for human readers.
459 */
460 #define likely(X)    (X)
461 #define unlikely(X)  (X)
462 
463 #include "hash.h"
464 #include "parse.h"
465 #include <stdio.h>
466 #include <stdlib.h>
467 #include <string.h>
468 #include <assert.h>
469 #include <stddef.h>
470 
471 /*
472 ** If compiling for a processor that lacks floating point support,
473 ** substitute integer for floating-point
474 */
475 #ifdef SQLITE_OMIT_FLOATING_POINT
476 # define double sqlite_int64
477 # define float sqlite_int64
478 # define LONGDOUBLE_TYPE sqlite_int64
479 # ifndef SQLITE_BIG_DBL
480 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
481 # endif
482 # define SQLITE_OMIT_DATETIME_FUNCS 1
483 # define SQLITE_OMIT_TRACE 1
484 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
485 # undef SQLITE_HAVE_ISNAN
486 #endif
487 #ifndef SQLITE_BIG_DBL
488 # define SQLITE_BIG_DBL (1e99)
489 #endif
490 
491 /*
492 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
493 ** afterward. Having this macro allows us to cause the C compiler
494 ** to omit code used by TEMP tables without messy #ifndef statements.
495 */
496 #ifdef SQLITE_OMIT_TEMPDB
497 #define OMIT_TEMPDB 1
498 #else
499 #define OMIT_TEMPDB 0
500 #endif
501 
502 /*
503 ** The "file format" number is an integer that is incremented whenever
504 ** the VDBE-level file format changes.  The following macros define the
505 ** the default file format for new databases and the maximum file format
506 ** that the library can read.
507 */
508 #define SQLITE_MAX_FILE_FORMAT 4
509 #ifndef SQLITE_DEFAULT_FILE_FORMAT
510 # define SQLITE_DEFAULT_FILE_FORMAT 4
511 #endif
512 
513 /*
514 ** Determine whether triggers are recursive by default.  This can be
515 ** changed at run-time using a pragma.
516 */
517 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
518 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
519 #endif
520 
521 /*
522 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
523 ** on the command-line
524 */
525 #ifndef SQLITE_TEMP_STORE
526 # define SQLITE_TEMP_STORE 1
527 # define SQLITE_TEMP_STORE_xc 1  /* Exclude from ctime.c */
528 #endif
529 
530 /*
531 ** If no value has been provided for SQLITE_MAX_WORKER_THREADS, or if
532 ** SQLITE_TEMP_STORE is set to 3 (never use temporary files), set it
533 ** to zero.
534 */
535 #if SQLITE_TEMP_STORE==3 || SQLITE_THREADSAFE==0
536 # undef SQLITE_MAX_WORKER_THREADS
537 # define SQLITE_MAX_WORKER_THREADS 0
538 #endif
539 #ifndef SQLITE_MAX_WORKER_THREADS
540 # define SQLITE_MAX_WORKER_THREADS 8
541 #endif
542 #ifndef SQLITE_DEFAULT_WORKER_THREADS
543 # define SQLITE_DEFAULT_WORKER_THREADS 0
544 #endif
545 #if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
546 # undef SQLITE_MAX_WORKER_THREADS
547 # define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
548 #endif
549 
550 /*
551 ** The default initial allocation for the pagecache when using separate
552 ** pagecaches for each database connection.  A positive number is the
553 ** number of pages.  A negative number N translations means that a buffer
554 ** of -1024*N bytes is allocated and used for as many pages as it will hold.
555 */
556 #ifndef SQLITE_DEFAULT_PCACHE_INITSZ
557 # define SQLITE_DEFAULT_PCACHE_INITSZ 100
558 #endif
559 
560 /*
561 ** GCC does not define the offsetof() macro so we'll have to do it
562 ** ourselves.
563 */
564 #ifndef offsetof
565 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
566 #endif
567 
568 /*
569 ** Macros to compute minimum and maximum of two numbers.
570 */
571 #define MIN(A,B) ((A)<(B)?(A):(B))
572 #define MAX(A,B) ((A)>(B)?(A):(B))
573 
574 /*
575 ** Swap two objects of type TYPE.
576 */
577 #define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
578 
579 /*
580 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
581 ** not, there are still machines out there that use EBCDIC.)
582 */
583 #if 'A' == '\301'
584 # define SQLITE_EBCDIC 1
585 #else
586 # define SQLITE_ASCII 1
587 #endif
588 
589 /*
590 ** Integers of known sizes.  These typedefs might change for architectures
591 ** where the sizes very.  Preprocessor macros are available so that the
592 ** types can be conveniently redefined at compile-type.  Like this:
593 **
594 **         cc '-DUINTPTR_TYPE=long long int' ...
595 */
596 #ifndef UINT32_TYPE
597 # ifdef HAVE_UINT32_T
598 #  define UINT32_TYPE uint32_t
599 # else
600 #  define UINT32_TYPE unsigned int
601 # endif
602 #endif
603 #ifndef UINT16_TYPE
604 # ifdef HAVE_UINT16_T
605 #  define UINT16_TYPE uint16_t
606 # else
607 #  define UINT16_TYPE unsigned short int
608 # endif
609 #endif
610 #ifndef INT16_TYPE
611 # ifdef HAVE_INT16_T
612 #  define INT16_TYPE int16_t
613 # else
614 #  define INT16_TYPE short int
615 # endif
616 #endif
617 #ifndef UINT8_TYPE
618 # ifdef HAVE_UINT8_T
619 #  define UINT8_TYPE uint8_t
620 # else
621 #  define UINT8_TYPE unsigned char
622 # endif
623 #endif
624 #ifndef INT8_TYPE
625 # ifdef HAVE_INT8_T
626 #  define INT8_TYPE int8_t
627 # else
628 #  define INT8_TYPE signed char
629 # endif
630 #endif
631 #ifndef LONGDOUBLE_TYPE
632 # define LONGDOUBLE_TYPE long double
633 #endif
634 typedef sqlite_int64 i64;          /* 8-byte signed integer */
635 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
636 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
637 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
638 typedef INT16_TYPE i16;            /* 2-byte signed integer */
639 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
640 typedef INT8_TYPE i8;              /* 1-byte signed integer */
641 
642 /*
643 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
644 ** that can be stored in a u32 without loss of data.  The value
645 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
646 ** have to specify the value in the less intuitive manner shown:
647 */
648 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
649 
650 /*
651 ** The datatype used to store estimates of the number of rows in a
652 ** table or index.  This is an unsigned integer type.  For 99.9% of
653 ** the world, a 32-bit integer is sufficient.  But a 64-bit integer
654 ** can be used at compile-time if desired.
655 */
656 #ifdef SQLITE_64BIT_STATS
657  typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
658 #else
659  typedef u32 tRowcnt;    /* 32-bit is the default */
660 #endif
661 
662 /*
663 ** Estimated quantities used for query planning are stored as 16-bit
664 ** logarithms.  For quantity X, the value stored is 10*log2(X).  This
665 ** gives a possible range of values of approximately 1.0e986 to 1e-986.
666 ** But the allowed values are "grainy".  Not every value is representable.
667 ** For example, quantities 16 and 17 are both represented by a LogEst
668 ** of 40.  However, since LogEst quantities are suppose to be estimates,
669 ** not exact values, this imprecision is not a problem.
670 **
671 ** "LogEst" is short for "Logarithmic Estimate".
672 **
673 ** Examples:
674 **      1 -> 0              20 -> 43          10000 -> 132
675 **      2 -> 10             25 -> 46          25000 -> 146
676 **      3 -> 16            100 -> 66        1000000 -> 199
677 **      4 -> 20           1000 -> 99        1048576 -> 200
678 **     10 -> 33           1024 -> 100    4294967296 -> 320
679 **
680 ** The LogEst can be negative to indicate fractional values.
681 ** Examples:
682 **
683 **    0.5 -> -10           0.1 -> -33        0.0625 -> -40
684 */
685 typedef INT16_TYPE LogEst;
686 
687 /*
688 ** Set the SQLITE_PTRSIZE macro to the number of bytes in a pointer
689 */
690 #ifndef SQLITE_PTRSIZE
691 # if defined(__SIZEOF_POINTER__)
692 #   define SQLITE_PTRSIZE __SIZEOF_POINTER__
693 # elif defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
694        defined(_M_ARM)   || defined(__arm__)    || defined(__x86)
695 #   define SQLITE_PTRSIZE 4
696 # else
697 #   define SQLITE_PTRSIZE 8
698 # endif
699 #endif
700 
701 /*
702 ** Macros to determine whether the machine is big or little endian,
703 ** and whether or not that determination is run-time or compile-time.
704 **
705 ** For best performance, an attempt is made to guess at the byte-order
706 ** using C-preprocessor macros.  If that is unsuccessful, or if
707 ** -DSQLITE_RUNTIME_BYTEORDER=1 is set, then byte-order is determined
708 ** at run-time.
709 */
710 #if (defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
711      defined(__x86_64) || defined(__x86_64__) || defined(_M_X64)  ||    \
712      defined(_M_AMD64) || defined(_M_ARM)     || defined(__x86)   ||    \
713      defined(__arm__)) && !defined(SQLITE_RUNTIME_BYTEORDER)
714 # define SQLITE_BYTEORDER    1234
715 # define SQLITE_BIGENDIAN    0
716 # define SQLITE_LITTLEENDIAN 1
717 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
718 #endif
719 #if (defined(sparc)    || defined(__ppc__))  \
720     && !defined(SQLITE_RUNTIME_BYTEORDER)
721 # define SQLITE_BYTEORDER    4321
722 # define SQLITE_BIGENDIAN    1
723 # define SQLITE_LITTLEENDIAN 0
724 # define SQLITE_UTF16NATIVE  SQLITE_UTF16BE
725 #endif
726 #if !defined(SQLITE_BYTEORDER)
727 # ifdef SQLITE_AMALGAMATION
728   const int sqlite3one = 1;
729 # else
730   extern const int sqlite3one;
731 # endif
732 # define SQLITE_BYTEORDER    0     /* 0 means "unknown at compile-time" */
733 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
734 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
735 # define SQLITE_UTF16NATIVE  (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
736 #endif
737 
738 /*
739 ** Constants for the largest and smallest possible 64-bit signed integers.
740 ** These macros are designed to work correctly on both 32-bit and 64-bit
741 ** compilers.
742 */
743 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
744 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
745 
746 /*
747 ** Round up a number to the next larger multiple of 8.  This is used
748 ** to force 8-byte alignment on 64-bit architectures.
749 */
750 #define ROUND8(x)     (((x)+7)&~7)
751 
752 /*
753 ** Round down to the nearest multiple of 8
754 */
755 #define ROUNDDOWN8(x) ((x)&~7)
756 
757 /*
758 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
759 ** macro is used only within assert() to verify that the code gets
760 ** all alignment restrictions correct.
761 **
762 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
763 ** underlying malloc() implementation might return us 4-byte aligned
764 ** pointers.  In that case, only verify 4-byte alignment.
765 */
766 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
767 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
768 #else
769 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
770 #endif
771 
772 /*
773 ** Disable MMAP on platforms where it is known to not work
774 */
775 #if defined(__OpenBSD__) || defined(__QNXNTO__)
776 # undef SQLITE_MAX_MMAP_SIZE
777 # define SQLITE_MAX_MMAP_SIZE 0
778 #endif
779 
780 /*
781 ** Default maximum size of memory used by memory-mapped I/O in the VFS
782 */
783 #ifdef __APPLE__
784 # include <TargetConditionals.h>
785 #endif
786 #ifndef SQLITE_MAX_MMAP_SIZE
787 # if defined(__linux__) \
788   || defined(_WIN32) \
789   || (defined(__APPLE__) && defined(__MACH__)) \
790   || defined(__sun) \
791   || defined(__FreeBSD__) \
792   || defined(__DragonFly__)
793 #   define SQLITE_MAX_MMAP_SIZE 0x7fff0000  /* 2147418112 */
794 # else
795 #   define SQLITE_MAX_MMAP_SIZE 0
796 # endif
797 # define SQLITE_MAX_MMAP_SIZE_xc 1 /* exclude from ctime.c */
798 #endif
799 
800 /*
801 ** The default MMAP_SIZE is zero on all platforms.  Or, even if a larger
802 ** default MMAP_SIZE is specified at compile-time, make sure that it does
803 ** not exceed the maximum mmap size.
804 */
805 #ifndef SQLITE_DEFAULT_MMAP_SIZE
806 # define SQLITE_DEFAULT_MMAP_SIZE 0
807 # define SQLITE_DEFAULT_MMAP_SIZE_xc 1  /* Exclude from ctime.c */
808 #endif
809 #if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
810 # undef SQLITE_DEFAULT_MMAP_SIZE
811 # define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
812 #endif
813 
814 /*
815 ** Only one of SQLITE_ENABLE_STAT3 or SQLITE_ENABLE_STAT4 can be defined.
816 ** Priority is given to SQLITE_ENABLE_STAT4.  If either are defined, also
817 ** define SQLITE_ENABLE_STAT3_OR_STAT4
818 */
819 #ifdef SQLITE_ENABLE_STAT4
820 # undef SQLITE_ENABLE_STAT3
821 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
822 #elif SQLITE_ENABLE_STAT3
823 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
824 #elif SQLITE_ENABLE_STAT3_OR_STAT4
825 # undef SQLITE_ENABLE_STAT3_OR_STAT4
826 #endif
827 
828 /*
829 ** SELECTTRACE_ENABLED will be either 1 or 0 depending on whether or not
830 ** the Select query generator tracing logic is turned on.
831 */
832 #if defined(SQLITE_DEBUG) || defined(SQLITE_ENABLE_SELECTTRACE)
833 # define SELECTTRACE_ENABLED 1
834 #else
835 # define SELECTTRACE_ENABLED 0
836 #endif
837 
838 /*
839 ** An instance of the following structure is used to store the busy-handler
840 ** callback for a given sqlite handle.
841 **
842 ** The sqlite.busyHandler member of the sqlite struct contains the busy
843 ** callback for the database handle. Each pager opened via the sqlite
844 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
845 ** callback is currently invoked only from within pager.c.
846 */
847 typedef struct BusyHandler BusyHandler;
848 struct BusyHandler {
849   int (*xFunc)(void *,int);  /* The busy callback */
850   void *pArg;                /* First arg to busy callback */
851   int nBusy;                 /* Incremented with each busy call */
852 };
853 
854 /*
855 ** Name of the master database table.  The master database table
856 ** is a special table that holds the names and attributes of all
857 ** user tables and indices.
858 */
859 #define MASTER_NAME       "sqlite_master"
860 #define TEMP_MASTER_NAME  "sqlite_temp_master"
861 
862 /*
863 ** The root-page of the master database table.
864 */
865 #define MASTER_ROOT       1
866 
867 /*
868 ** The name of the schema table.
869 */
870 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
871 
872 /*
873 ** A convenience macro that returns the number of elements in
874 ** an array.
875 */
876 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
877 
878 /*
879 ** Determine if the argument is a power of two
880 */
881 #define IsPowerOfTwo(X) (((X)&((X)-1))==0)
882 
883 /*
884 ** The following value as a destructor means to use sqlite3DbFree().
885 ** The sqlite3DbFree() routine requires two parameters instead of the
886 ** one parameter that destructors normally want.  So we have to introduce
887 ** this magic value that the code knows to handle differently.  Any
888 ** pointer will work here as long as it is distinct from SQLITE_STATIC
889 ** and SQLITE_TRANSIENT.
890 */
891 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3MallocSize)
892 
893 /*
894 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
895 ** not support Writable Static Data (WSD) such as global and static variables.
896 ** All variables must either be on the stack or dynamically allocated from
897 ** the heap.  When WSD is unsupported, the variable declarations scattered
898 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
899 ** macro is used for this purpose.  And instead of referencing the variable
900 ** directly, we use its constant as a key to lookup the run-time allocated
901 ** buffer that holds real variable.  The constant is also the initializer
902 ** for the run-time allocated buffer.
903 **
904 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
905 ** macros become no-ops and have zero performance impact.
906 */
907 #ifdef SQLITE_OMIT_WSD
908   #define SQLITE_WSD const
909   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
910   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
911   int sqlite3_wsd_init(int N, int J);
912   void *sqlite3_wsd_find(void *K, int L);
913 #else
914   #define SQLITE_WSD
915   #define GLOBAL(t,v) v
916   #define sqlite3GlobalConfig sqlite3Config
917 #endif
918 
919 /*
920 ** The following macros are used to suppress compiler warnings and to
921 ** make it clear to human readers when a function parameter is deliberately
922 ** left unused within the body of a function. This usually happens when
923 ** a function is called via a function pointer. For example the
924 ** implementation of an SQL aggregate step callback may not use the
925 ** parameter indicating the number of arguments passed to the aggregate,
926 ** if it knows that this is enforced elsewhere.
927 **
928 ** When a function parameter is not used at all within the body of a function,
929 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
930 ** However, these macros may also be used to suppress warnings related to
931 ** parameters that may or may not be used depending on compilation options.
932 ** For example those parameters only used in assert() statements. In these
933 ** cases the parameters are named as per the usual conventions.
934 */
935 #define UNUSED_PARAMETER(x) (void)(x)
936 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
937 
938 /*
939 ** Forward references to structures
940 */
941 typedef struct AggInfo AggInfo;
942 typedef struct AuthContext AuthContext;
943 typedef struct AutoincInfo AutoincInfo;
944 typedef struct Bitvec Bitvec;
945 typedef struct CollSeq CollSeq;
946 typedef struct Column Column;
947 typedef struct Db Db;
948 typedef struct Schema Schema;
949 typedef struct Expr Expr;
950 typedef struct ExprList ExprList;
951 typedef struct ExprSpan ExprSpan;
952 typedef struct FKey FKey;
953 typedef struct FuncDestructor FuncDestructor;
954 typedef struct FuncDef FuncDef;
955 typedef struct FuncDefHash FuncDefHash;
956 typedef struct IdList IdList;
957 typedef struct Index Index;
958 typedef struct IndexSample IndexSample;
959 typedef struct KeyClass KeyClass;
960 typedef struct KeyInfo KeyInfo;
961 typedef struct Lookaside Lookaside;
962 typedef struct LookasideSlot LookasideSlot;
963 typedef struct Module Module;
964 typedef struct NameContext NameContext;
965 typedef struct Parse Parse;
966 typedef struct PrintfArguments PrintfArguments;
967 typedef struct RowSet RowSet;
968 typedef struct Savepoint Savepoint;
969 typedef struct Select Select;
970 typedef struct SQLiteThread SQLiteThread;
971 typedef struct SelectDest SelectDest;
972 typedef struct SrcList SrcList;
973 typedef struct StrAccum StrAccum;
974 typedef struct Table Table;
975 typedef struct TableLock TableLock;
976 typedef struct Token Token;
977 typedef struct TreeView TreeView;
978 typedef struct Trigger Trigger;
979 typedef struct TriggerPrg TriggerPrg;
980 typedef struct TriggerStep TriggerStep;
981 typedef struct UnpackedRecord UnpackedRecord;
982 typedef struct VTable VTable;
983 typedef struct VtabCtx VtabCtx;
984 typedef struct Walker Walker;
985 typedef struct WhereInfo WhereInfo;
986 typedef struct With With;
987 
988 /*
989 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
990 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
991 ** pointer types (i.e. FuncDef) defined above.
992 */
993 #include "btree.h"
994 #include "vdbe.h"
995 #include "pager.h"
996 #include "pcache.h"
997 
998 #include "os.h"
999 #include "mutex.h"
1000 
1001 
1002 /*
1003 ** Each database file to be accessed by the system is an instance
1004 ** of the following structure.  There are normally two of these structures
1005 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
1006 ** aDb[1] is the database file used to hold temporary tables.  Additional
1007 ** databases may be attached.
1008 */
1009 struct Db {
1010   char *zName;         /* Name of this database */
1011   Btree *pBt;          /* The B*Tree structure for this database file */
1012   u8 safety_level;     /* How aggressive at syncing data to disk */
1013   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
1014 };
1015 
1016 /*
1017 ** An instance of the following structure stores a database schema.
1018 **
1019 ** Most Schema objects are associated with a Btree.  The exception is
1020 ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
1021 ** In shared cache mode, a single Schema object can be shared by multiple
1022 ** Btrees that refer to the same underlying BtShared object.
1023 **
1024 ** Schema objects are automatically deallocated when the last Btree that
1025 ** references them is destroyed.   The TEMP Schema is manually freed by
1026 ** sqlite3_close().
1027 *
1028 ** A thread must be holding a mutex on the corresponding Btree in order
1029 ** to access Schema content.  This implies that the thread must also be
1030 ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
1031 ** For a TEMP Schema, only the connection mutex is required.
1032 */
1033 struct Schema {
1034   int schema_cookie;   /* Database schema version number for this file */
1035   int iGeneration;     /* Generation counter.  Incremented with each change */
1036   Hash tblHash;        /* All tables indexed by name */
1037   Hash idxHash;        /* All (named) indices indexed by name */
1038   Hash trigHash;       /* All triggers indexed by name */
1039   Hash fkeyHash;       /* All foreign keys by referenced table name */
1040   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
1041   u8 file_format;      /* Schema format version for this file */
1042   u8 enc;              /* Text encoding used by this database */
1043   u16 schemaFlags;     /* Flags associated with this schema */
1044   int cache_size;      /* Number of pages to use in the cache */
1045 };
1046 
1047 /*
1048 ** These macros can be used to test, set, or clear bits in the
1049 ** Db.pSchema->flags field.
1050 */
1051 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))
1052 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->schemaFlags&(P))!=0)
1053 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->schemaFlags|=(P)
1054 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->schemaFlags&=~(P)
1055 
1056 /*
1057 ** Allowed values for the DB.pSchema->flags field.
1058 **
1059 ** The DB_SchemaLoaded flag is set after the database schema has been
1060 ** read into internal hash tables.
1061 **
1062 ** DB_UnresetViews means that one or more views have column names that
1063 ** have been filled out.  If the schema changes, these column names might
1064 ** changes and so the view will need to be reset.
1065 */
1066 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
1067 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
1068 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
1069 
1070 /*
1071 ** The number of different kinds of things that can be limited
1072 ** using the sqlite3_limit() interface.
1073 */
1074 #define SQLITE_N_LIMIT (SQLITE_LIMIT_WORKER_THREADS+1)
1075 
1076 /*
1077 ** Lookaside malloc is a set of fixed-size buffers that can be used
1078 ** to satisfy small transient memory allocation requests for objects
1079 ** associated with a particular database connection.  The use of
1080 ** lookaside malloc provides a significant performance enhancement
1081 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
1082 ** SQL statements.
1083 **
1084 ** The Lookaside structure holds configuration information about the
1085 ** lookaside malloc subsystem.  Each available memory allocation in
1086 ** the lookaside subsystem is stored on a linked list of LookasideSlot
1087 ** objects.
1088 **
1089 ** Lookaside allocations are only allowed for objects that are associated
1090 ** with a particular database connection.  Hence, schema information cannot
1091 ** be stored in lookaside because in shared cache mode the schema information
1092 ** is shared by multiple database connections.  Therefore, while parsing
1093 ** schema information, the Lookaside.bEnabled flag is cleared so that
1094 ** lookaside allocations are not used to construct the schema objects.
1095 */
1096 struct Lookaside {
1097   u16 sz;                 /* Size of each buffer in bytes */
1098   u8 bEnabled;            /* False to disable new lookaside allocations */
1099   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
1100   int nOut;               /* Number of buffers currently checked out */
1101   int mxOut;              /* Highwater mark for nOut */
1102   int anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
1103   LookasideSlot *pFree;   /* List of available buffers */
1104   void *pStart;           /* First byte of available memory space */
1105   void *pEnd;             /* First byte past end of available space */
1106 };
1107 struct LookasideSlot {
1108   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
1109 };
1110 
1111 /*
1112 ** A hash table for function definitions.
1113 **
1114 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
1115 ** Collisions are on the FuncDef.pHash chain.
1116 */
1117 struct FuncDefHash {
1118   FuncDef *a[23];       /* Hash table for functions */
1119 };
1120 
1121 #ifdef SQLITE_USER_AUTHENTICATION
1122 /*
1123 ** Information held in the "sqlite3" database connection object and used
1124 ** to manage user authentication.
1125 */
1126 typedef struct sqlite3_userauth sqlite3_userauth;
1127 struct sqlite3_userauth {
1128   u8 authLevel;                 /* Current authentication level */
1129   int nAuthPW;                  /* Size of the zAuthPW in bytes */
1130   char *zAuthPW;                /* Password used to authenticate */
1131   char *zAuthUser;              /* User name used to authenticate */
1132 };
1133 
1134 /* Allowed values for sqlite3_userauth.authLevel */
1135 #define UAUTH_Unknown     0     /* Authentication not yet checked */
1136 #define UAUTH_Fail        1     /* User authentication failed */
1137 #define UAUTH_User        2     /* Authenticated as a normal user */
1138 #define UAUTH_Admin       3     /* Authenticated as an administrator */
1139 
1140 /* Functions used only by user authorization logic */
1141 int sqlite3UserAuthTable(const char*);
1142 int sqlite3UserAuthCheckLogin(sqlite3*,const char*,u8*);
1143 void sqlite3UserAuthInit(sqlite3*);
1144 void sqlite3CryptFunc(sqlite3_context*,int,sqlite3_value**);
1145 
1146 #endif /* SQLITE_USER_AUTHENTICATION */
1147 
1148 /*
1149 ** typedef for the authorization callback function.
1150 */
1151 #ifdef SQLITE_USER_AUTHENTICATION
1152   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1153                                const char*, const char*);
1154 #else
1155   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1156                                const char*);
1157 #endif
1158 
1159 
1160 /*
1161 ** Each database connection is an instance of the following structure.
1162 */
1163 struct sqlite3 {
1164   sqlite3_vfs *pVfs;            /* OS Interface */
1165   struct Vdbe *pVdbe;           /* List of active virtual machines */
1166   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
1167   sqlite3_mutex *mutex;         /* Connection mutex */
1168   Db *aDb;                      /* All backends */
1169   int nDb;                      /* Number of backends currently in use */
1170   int flags;                    /* Miscellaneous flags. See below */
1171   i64 lastRowid;                /* ROWID of most recent insert (see above) */
1172   i64 szMmap;                   /* Default mmap_size setting */
1173   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
1174   int errCode;                  /* Most recent error code (SQLITE_*) */
1175   int errMask;                  /* & result codes with this before returning */
1176   u16 dbOptFlags;               /* Flags to enable/disable optimizations */
1177   u8 enc;                       /* Text encoding */
1178   u8 autoCommit;                /* The auto-commit flag. */
1179   u8 temp_store;                /* 1: file 2: memory 0: default */
1180   u8 mallocFailed;              /* True if we have seen a malloc failure */
1181   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
1182   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
1183   u8 suppressErr;               /* Do not issue error messages if true */
1184   u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
1185   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
1186   int nextPagesize;             /* Pagesize after VACUUM if >0 */
1187   u32 magic;                    /* Magic number for detect library misuse */
1188   int nChange;                  /* Value returned by sqlite3_changes() */
1189   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
1190   int aLimit[SQLITE_N_LIMIT];   /* Limits */
1191   int nMaxSorterMmap;           /* Maximum size of regions mapped by sorter */
1192   struct sqlite3InitInfo {      /* Information used during initialization */
1193     int newTnum;                /* Rootpage of table being initialized */
1194     u8 iDb;                     /* Which db file is being initialized */
1195     u8 busy;                    /* TRUE if currently initializing */
1196     u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
1197     u8 imposterTable;           /* Building an imposter table */
1198   } init;
1199   int nVdbeActive;              /* Number of VDBEs currently running */
1200   int nVdbeRead;                /* Number of active VDBEs that read or write */
1201   int nVdbeWrite;               /* Number of active VDBEs that read and write */
1202   int nVdbeExec;                /* Number of nested calls to VdbeExec() */
1203   int nVDestroy;                /* Number of active OP_VDestroy operations */
1204   int nExtension;               /* Number of loaded extensions */
1205   void **aExtension;            /* Array of shared library handles */
1206   void (*xTrace)(void*,const char*);        /* Trace function */
1207   void *pTraceArg;                          /* Argument to the trace function */
1208   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
1209   void *pProfileArg;                        /* Argument to profile function */
1210   void *pCommitArg;                 /* Argument to xCommitCallback() */
1211   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
1212   void *pRollbackArg;               /* Argument to xRollbackCallback() */
1213   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
1214   void *pUpdateArg;
1215   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
1216 #ifndef SQLITE_OMIT_WAL
1217   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
1218   void *pWalArg;
1219 #endif
1220   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
1221   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
1222   void *pCollNeededArg;
1223   sqlite3_value *pErr;          /* Most recent error message */
1224   union {
1225     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
1226     double notUsed1;            /* Spacer */
1227   } u1;
1228   Lookaside lookaside;          /* Lookaside malloc configuration */
1229 #ifndef SQLITE_OMIT_AUTHORIZATION
1230   sqlite3_xauth xAuth;          /* Access authorization function */
1231   void *pAuthArg;               /* 1st argument to the access auth function */
1232 #endif
1233 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
1234   int (*xProgress)(void *);     /* The progress callback */
1235   void *pProgressArg;           /* Argument to the progress callback */
1236   unsigned nProgressOps;        /* Number of opcodes for progress callback */
1237 #endif
1238 #ifndef SQLITE_OMIT_VIRTUALTABLE
1239   int nVTrans;                  /* Allocated size of aVTrans */
1240   Hash aModule;                 /* populated by sqlite3_create_module() */
1241   VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
1242   VTable **aVTrans;             /* Virtual tables with open transactions */
1243   VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
1244 #endif
1245   FuncDefHash aFunc;            /* Hash table of connection functions */
1246   Hash aCollSeq;                /* All collating sequences */
1247   BusyHandler busyHandler;      /* Busy callback */
1248   Db aDbStatic[2];              /* Static space for the 2 default backends */
1249   Savepoint *pSavepoint;        /* List of active savepoints */
1250   int busyTimeout;              /* Busy handler timeout, in msec */
1251   int nSavepoint;               /* Number of non-transaction savepoints */
1252   int nStatement;               /* Number of nested statement-transactions  */
1253   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
1254   i64 nDeferredImmCons;         /* Net deferred immediate constraints */
1255   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
1256 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
1257   /* The following variables are all protected by the STATIC_MASTER
1258   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
1259   **
1260   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
1261   ** unlock so that it can proceed.
1262   **
1263   ** When X.pBlockingConnection==Y, that means that something that X tried
1264   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
1265   ** held by Y.
1266   */
1267   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
1268   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
1269   void *pUnlockArg;                     /* Argument to xUnlockNotify */
1270   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
1271   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
1272 #endif
1273 #ifdef SQLITE_USER_AUTHENTICATION
1274   sqlite3_userauth auth;        /* User authentication information */
1275 #endif
1276 };
1277 
1278 /*
1279 ** A macro to discover the encoding of a database.
1280 */
1281 #define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
1282 #define ENC(db)        ((db)->enc)
1283 
1284 /*
1285 ** Possible values for the sqlite3.flags.
1286 */
1287 #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
1288 #define SQLITE_InternChanges  0x00000002  /* Uncommitted Hash table changes */
1289 #define SQLITE_FullFSync      0x00000004  /* Use full fsync on the backend */
1290 #define SQLITE_CkptFullFSync  0x00000008  /* Use full fsync for checkpoint */
1291 #define SQLITE_CacheSpill     0x00000010  /* OK to spill pager cache */
1292 #define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
1293 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
1294 #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
1295                                           /*   DELETE, or UPDATE and return */
1296                                           /*   the count using a callback. */
1297 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
1298                                           /*   result set is empty */
1299 #define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
1300 #define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
1301 #define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
1302 #define SQLITE_VdbeAddopTrace 0x00001000  /* Trace sqlite3VdbeAddOp() calls */
1303 #define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
1304 #define SQLITE_ReadUncommitted 0x0004000  /* For shared-cache mode */
1305 #define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
1306 #define SQLITE_RecoveryMode   0x00010000  /* Ignore schema errors */
1307 #define SQLITE_ReverseOrder   0x00020000  /* Reverse unordered SELECTs */
1308 #define SQLITE_RecTriggers    0x00040000  /* Enable recursive triggers */
1309 #define SQLITE_ForeignKeys    0x00080000  /* Enforce foreign key constraints  */
1310 #define SQLITE_AutoIndex      0x00100000  /* Enable automatic indexes */
1311 #define SQLITE_PreferBuiltin  0x00200000  /* Preference to built-in funcs */
1312 #define SQLITE_LoadExtension  0x00400000  /* Enable load_extension */
1313 #define SQLITE_EnableTrigger  0x00800000  /* True to enable triggers */
1314 #define SQLITE_DeferFKs       0x01000000  /* Defer all FK constraints */
1315 #define SQLITE_QueryOnly      0x02000000  /* Disable database changes */
1316 #define SQLITE_VdbeEQP        0x04000000  /* Debug EXPLAIN QUERY PLAN */
1317 #define SQLITE_Vacuum         0x08000000  /* Currently in a VACUUM */
1318 #define SQLITE_CellSizeCk     0x10000000  /* Check btree cell sizes on load */
1319 
1320 
1321 /*
1322 ** Bits of the sqlite3.dbOptFlags field that are used by the
1323 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
1324 ** selectively disable various optimizations.
1325 */
1326 #define SQLITE_QueryFlattener 0x0001   /* Query flattening */
1327 #define SQLITE_ColumnCache    0x0002   /* Column cache */
1328 #define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
1329 #define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
1330 /*                not used    0x0010   // Was: SQLITE_IdxRealAsInt */
1331 #define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
1332 #define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
1333 #define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
1334 #define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
1335 #define SQLITE_Transitive     0x0200   /* Transitive constraints */
1336 #define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
1337 #define SQLITE_Stat34         0x0800   /* Use STAT3 or STAT4 data */
1338 #define SQLITE_CursorHints    0x2000   /* Add OP_CursorHint opcodes */
1339 #define SQLITE_AllOpts        0xffff   /* All optimizations */
1340 
1341 /*
1342 ** Macros for testing whether or not optimizations are enabled or disabled.
1343 */
1344 #ifndef SQLITE_OMIT_BUILTIN_TEST
1345 #define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
1346 #define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
1347 #else
1348 #define OptimizationDisabled(db, mask)  0
1349 #define OptimizationEnabled(db, mask)   1
1350 #endif
1351 
1352 /*
1353 ** Return true if it OK to factor constant expressions into the initialization
1354 ** code. The argument is a Parse object for the code generator.
1355 */
1356 #define ConstFactorOk(P) ((P)->okConstFactor)
1357 
1358 /*
1359 ** Possible values for the sqlite.magic field.
1360 ** The numbers are obtained at random and have no special meaning, other
1361 ** than being distinct from one another.
1362 */
1363 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
1364 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
1365 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
1366 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
1367 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
1368 #define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */
1369 
1370 /*
1371 ** Each SQL function is defined by an instance of the following
1372 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
1373 ** hash table.  When multiple functions have the same name, the hash table
1374 ** points to a linked list of these structures.
1375 */
1376 struct FuncDef {
1377   i16 nArg;            /* Number of arguments.  -1 means unlimited */
1378   u16 funcFlags;       /* Some combination of SQLITE_FUNC_* */
1379   void *pUserData;     /* User data parameter */
1380   FuncDef *pNext;      /* Next function with same name */
1381   void (*xSFunc)(sqlite3_context*,int,sqlite3_value**); /* func or agg-step */
1382   void (*xFinalize)(sqlite3_context*);                  /* Agg finalizer */
1383   char *zName;         /* SQL name of the function. */
1384   FuncDef *pHash;      /* Next with a different name but the same hash */
1385   FuncDestructor *pDestructor;   /* Reference counted destructor function */
1386 };
1387 
1388 /*
1389 ** This structure encapsulates a user-function destructor callback (as
1390 ** configured using create_function_v2()) and a reference counter. When
1391 ** create_function_v2() is called to create a function with a destructor,
1392 ** a single object of this type is allocated. FuncDestructor.nRef is set to
1393 ** the number of FuncDef objects created (either 1 or 3, depending on whether
1394 ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
1395 ** member of each of the new FuncDef objects is set to point to the allocated
1396 ** FuncDestructor.
1397 **
1398 ** Thereafter, when one of the FuncDef objects is deleted, the reference
1399 ** count on this object is decremented. When it reaches 0, the destructor
1400 ** is invoked and the FuncDestructor structure freed.
1401 */
1402 struct FuncDestructor {
1403   int nRef;
1404   void (*xDestroy)(void *);
1405   void *pUserData;
1406 };
1407 
1408 /*
1409 ** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
1410 ** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  And
1411 ** SQLITE_FUNC_CONSTANT must be the same as SQLITE_DETERMINISTIC.  There
1412 ** are assert() statements in the code to verify this.
1413 */
1414 #define SQLITE_FUNC_ENCMASK  0x0003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
1415 #define SQLITE_FUNC_LIKE     0x0004 /* Candidate for the LIKE optimization */
1416 #define SQLITE_FUNC_CASE     0x0008 /* Case-sensitive LIKE-type function */
1417 #define SQLITE_FUNC_EPHEM    0x0010 /* Ephemeral.  Delete with VDBE */
1418 #define SQLITE_FUNC_NEEDCOLL 0x0020 /* sqlite3GetFuncCollSeq() might be called*/
1419 #define SQLITE_FUNC_LENGTH   0x0040 /* Built-in length() function */
1420 #define SQLITE_FUNC_TYPEOF   0x0080 /* Built-in typeof() function */
1421 #define SQLITE_FUNC_COUNT    0x0100 /* Built-in count(*) aggregate */
1422 #define SQLITE_FUNC_COALESCE 0x0200 /* Built-in coalesce() or ifnull() */
1423 #define SQLITE_FUNC_UNLIKELY 0x0400 /* Built-in unlikely() function */
1424 #define SQLITE_FUNC_CONSTANT 0x0800 /* Constant inputs give a constant output */
1425 #define SQLITE_FUNC_MINMAX   0x1000 /* True for min() and max() aggregates */
1426 #define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
1427                                     ** single query - might change over time */
1428 
1429 /*
1430 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
1431 ** used to create the initializers for the FuncDef structures.
1432 **
1433 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
1434 **     Used to create a scalar function definition of a function zName
1435 **     implemented by C function xFunc that accepts nArg arguments. The
1436 **     value passed as iArg is cast to a (void*) and made available
1437 **     as the user-data (sqlite3_user_data()) for the function. If
1438 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
1439 **
1440 **   VFUNCTION(zName, nArg, iArg, bNC, xFunc)
1441 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
1442 **
1443 **   DFUNCTION(zName, nArg, iArg, bNC, xFunc)
1444 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
1445 **     adds the SQLITE_FUNC_SLOCHNG flag.  Used for date & time functions
1446 **     and functions like sqlite_version() that can change, but not during
1447 **     a single query.
1448 **
1449 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
1450 **     Used to create an aggregate function definition implemented by
1451 **     the C functions xStep and xFinal. The first four parameters
1452 **     are interpreted in the same way as the first 4 parameters to
1453 **     FUNCTION().
1454 **
1455 **   LIKEFUNC(zName, nArg, pArg, flags)
1456 **     Used to create a scalar function definition of a function zName
1457 **     that accepts nArg arguments and is implemented by a call to C
1458 **     function likeFunc. Argument pArg is cast to a (void *) and made
1459 **     available as the function user-data (sqlite3_user_data()). The
1460 **     FuncDef.flags variable is set to the value passed as the flags
1461 **     parameter.
1462 */
1463 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1464   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1465    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, 0, 0}
1466 #define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1467   {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1468    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, 0, 0}
1469 #define DFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1470   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1471    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, 0, 0}
1472 #define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
1473   {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
1474    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, 0, 0}
1475 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
1476   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1477    pArg, 0, xFunc, 0, #zName, 0, 0}
1478 #define LIKEFUNC(zName, nArg, arg, flags) \
1479   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
1480    (void *)arg, 0, likeFunc, 0, #zName, 0, 0}
1481 #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
1482   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
1483    SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,#zName,0,0}
1484 #define AGGREGATE2(zName, nArg, arg, nc, xStep, xFinal, extraFlags) \
1485   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|extraFlags, \
1486    SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,#zName,0,0}
1487 
1488 /*
1489 ** All current savepoints are stored in a linked list starting at
1490 ** sqlite3.pSavepoint. The first element in the list is the most recently
1491 ** opened savepoint. Savepoints are added to the list by the vdbe
1492 ** OP_Savepoint instruction.
1493 */
1494 struct Savepoint {
1495   char *zName;                        /* Savepoint name (nul-terminated) */
1496   i64 nDeferredCons;                  /* Number of deferred fk violations */
1497   i64 nDeferredImmCons;               /* Number of deferred imm fk. */
1498   Savepoint *pNext;                   /* Parent savepoint (if any) */
1499 };
1500 
1501 /*
1502 ** The following are used as the second parameter to sqlite3Savepoint(),
1503 ** and as the P1 argument to the OP_Savepoint instruction.
1504 */
1505 #define SAVEPOINT_BEGIN      0
1506 #define SAVEPOINT_RELEASE    1
1507 #define SAVEPOINT_ROLLBACK   2
1508 
1509 
1510 /*
1511 ** Each SQLite module (virtual table definition) is defined by an
1512 ** instance of the following structure, stored in the sqlite3.aModule
1513 ** hash table.
1514 */
1515 struct Module {
1516   const sqlite3_module *pModule;       /* Callback pointers */
1517   const char *zName;                   /* Name passed to create_module() */
1518   void *pAux;                          /* pAux passed to create_module() */
1519   void (*xDestroy)(void *);            /* Module destructor function */
1520   Table *pEpoTab;                      /* Eponymous table for this module */
1521 };
1522 
1523 /*
1524 ** information about each column of an SQL table is held in an instance
1525 ** of this structure.
1526 */
1527 struct Column {
1528   char *zName;     /* Name of this column */
1529   Expr *pDflt;     /* Default value of this column */
1530   char *zDflt;     /* Original text of the default value */
1531   char *zType;     /* Data type for this column */
1532   char *zColl;     /* Collating sequence.  If NULL, use the default */
1533   u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
1534   char affinity;   /* One of the SQLITE_AFF_... values */
1535   u8 szEst;        /* Estimated size of value in this column. sizeof(INT)==1 */
1536   u8 colFlags;     /* Boolean properties.  See COLFLAG_ defines below */
1537 };
1538 
1539 /* Allowed values for Column.colFlags:
1540 */
1541 #define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
1542 #define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */
1543 
1544 /*
1545 ** A "Collating Sequence" is defined by an instance of the following
1546 ** structure. Conceptually, a collating sequence consists of a name and
1547 ** a comparison routine that defines the order of that sequence.
1548 **
1549 ** If CollSeq.xCmp is NULL, it means that the
1550 ** collating sequence is undefined.  Indices built on an undefined
1551 ** collating sequence may not be read or written.
1552 */
1553 struct CollSeq {
1554   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
1555   u8 enc;               /* Text encoding handled by xCmp() */
1556   void *pUser;          /* First argument to xCmp() */
1557   int (*xCmp)(void*,int, const void*, int, const void*);
1558   void (*xDel)(void*);  /* Destructor for pUser */
1559 };
1560 
1561 /*
1562 ** A sort order can be either ASC or DESC.
1563 */
1564 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
1565 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
1566 #define SQLITE_SO_UNDEFINED -1 /* No sort order specified */
1567 
1568 /*
1569 ** Column affinity types.
1570 **
1571 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
1572 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
1573 ** the speed a little by numbering the values consecutively.
1574 **
1575 ** But rather than start with 0 or 1, we begin with 'A'.  That way,
1576 ** when multiple affinity types are concatenated into a string and
1577 ** used as the P4 operand, they will be more readable.
1578 **
1579 ** Note also that the numeric types are grouped together so that testing
1580 ** for a numeric type is a single comparison.  And the BLOB type is first.
1581 */
1582 #define SQLITE_AFF_BLOB     'A'
1583 #define SQLITE_AFF_TEXT     'B'
1584 #define SQLITE_AFF_NUMERIC  'C'
1585 #define SQLITE_AFF_INTEGER  'D'
1586 #define SQLITE_AFF_REAL     'E'
1587 
1588 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
1589 
1590 /*
1591 ** The SQLITE_AFF_MASK values masks off the significant bits of an
1592 ** affinity value.
1593 */
1594 #define SQLITE_AFF_MASK     0x47
1595 
1596 /*
1597 ** Additional bit values that can be ORed with an affinity without
1598 ** changing the affinity.
1599 **
1600 ** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
1601 ** It causes an assert() to fire if either operand to a comparison
1602 ** operator is NULL.  It is added to certain comparison operators to
1603 ** prove that the operands are always NOT NULL.
1604 */
1605 #define SQLITE_JUMPIFNULL   0x10  /* jumps if either operand is NULL */
1606 #define SQLITE_STOREP2      0x20  /* Store result in reg[P2] rather than jump */
1607 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
1608 #define SQLITE_NOTNULL      0x90  /* Assert that operands are never NULL */
1609 
1610 /*
1611 ** An object of this type is created for each virtual table present in
1612 ** the database schema.
1613 **
1614 ** If the database schema is shared, then there is one instance of this
1615 ** structure for each database connection (sqlite3*) that uses the shared
1616 ** schema. This is because each database connection requires its own unique
1617 ** instance of the sqlite3_vtab* handle used to access the virtual table
1618 ** implementation. sqlite3_vtab* handles can not be shared between
1619 ** database connections, even when the rest of the in-memory database
1620 ** schema is shared, as the implementation often stores the database
1621 ** connection handle passed to it via the xConnect() or xCreate() method
1622 ** during initialization internally. This database connection handle may
1623 ** then be used by the virtual table implementation to access real tables
1624 ** within the database. So that they appear as part of the callers
1625 ** transaction, these accesses need to be made via the same database
1626 ** connection as that used to execute SQL operations on the virtual table.
1627 **
1628 ** All VTable objects that correspond to a single table in a shared
1629 ** database schema are initially stored in a linked-list pointed to by
1630 ** the Table.pVTable member variable of the corresponding Table object.
1631 ** When an sqlite3_prepare() operation is required to access the virtual
1632 ** table, it searches the list for the VTable that corresponds to the
1633 ** database connection doing the preparing so as to use the correct
1634 ** sqlite3_vtab* handle in the compiled query.
1635 **
1636 ** When an in-memory Table object is deleted (for example when the
1637 ** schema is being reloaded for some reason), the VTable objects are not
1638 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
1639 ** immediately. Instead, they are moved from the Table.pVTable list to
1640 ** another linked list headed by the sqlite3.pDisconnect member of the
1641 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
1642 ** next time a statement is prepared using said sqlite3*. This is done
1643 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
1644 ** Refer to comments above function sqlite3VtabUnlockList() for an
1645 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
1646 ** list without holding the corresponding sqlite3.mutex mutex.
1647 **
1648 ** The memory for objects of this type is always allocated by
1649 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
1650 ** the first argument.
1651 */
1652 struct VTable {
1653   sqlite3 *db;              /* Database connection associated with this table */
1654   Module *pMod;             /* Pointer to module implementation */
1655   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
1656   int nRef;                 /* Number of pointers to this structure */
1657   u8 bConstraint;           /* True if constraints are supported */
1658   int iSavepoint;           /* Depth of the SAVEPOINT stack */
1659   VTable *pNext;            /* Next in linked list (see above) */
1660 };
1661 
1662 /*
1663 ** The schema for each SQL table and view is represented in memory
1664 ** by an instance of the following structure.
1665 */
1666 struct Table {
1667   char *zName;         /* Name of the table or view */
1668   Column *aCol;        /* Information about each column */
1669   Index *pIndex;       /* List of SQL indexes on this table. */
1670   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
1671   FKey *pFKey;         /* Linked list of all foreign keys in this table */
1672   char *zColAff;       /* String defining the affinity of each column */
1673   ExprList *pCheck;    /* All CHECK constraints */
1674                        /*   ... also used as column name list in a VIEW */
1675   int tnum;            /* Root BTree page for this table */
1676   i16 iPKey;           /* If not negative, use aCol[iPKey] as the rowid */
1677   i16 nCol;            /* Number of columns in this table */
1678   u16 nRef;            /* Number of pointers to this Table */
1679   LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
1680   LogEst szTabRow;     /* Estimated size of each table row in bytes */
1681 #ifdef SQLITE_ENABLE_COSTMULT
1682   LogEst costMult;     /* Cost multiplier for using this table */
1683 #endif
1684   u8 tabFlags;         /* Mask of TF_* values */
1685   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
1686 #ifndef SQLITE_OMIT_ALTERTABLE
1687   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
1688 #endif
1689 #ifndef SQLITE_OMIT_VIRTUALTABLE
1690   int nModuleArg;      /* Number of arguments to the module */
1691   char **azModuleArg;  /* 0: module 1: schema 2: vtab name 3...: args */
1692   VTable *pVTable;     /* List of VTable objects. */
1693 #endif
1694   Trigger *pTrigger;   /* List of triggers stored in pSchema */
1695   Schema *pSchema;     /* Schema that contains this table */
1696   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
1697 };
1698 
1699 /*
1700 ** Allowed values for Table.tabFlags.
1701 **
1702 ** TF_OOOHidden applies to tables or view that have hidden columns that are
1703 ** followed by non-hidden columns.  Example:  "CREATE VIRTUAL TABLE x USING
1704 ** vtab1(a HIDDEN, b);".  Since "b" is a non-hidden column but "a" is hidden,
1705 ** the TF_OOOHidden attribute would apply in this case.  Such tables require
1706 ** special handling during INSERT processing.
1707 */
1708 #define TF_Readonly        0x01    /* Read-only system table */
1709 #define TF_Ephemeral       0x02    /* An ephemeral table */
1710 #define TF_HasPrimaryKey   0x04    /* Table has a primary key */
1711 #define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
1712 #define TF_Virtual         0x10    /* Is a virtual table */
1713 #define TF_WithoutRowid    0x20    /* No rowid.  PRIMARY KEY is the key */
1714 #define TF_NoVisibleRowid  0x40    /* No user-visible "rowid" column */
1715 #define TF_OOOHidden       0x80    /* Out-of-Order hidden columns */
1716 
1717 
1718 /*
1719 ** Test to see whether or not a table is a virtual table.  This is
1720 ** done as a macro so that it will be optimized out when virtual
1721 ** table support is omitted from the build.
1722 */
1723 #ifndef SQLITE_OMIT_VIRTUALTABLE
1724 #  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
1725 #else
1726 #  define IsVirtual(X)      0
1727 #endif
1728 
1729 /*
1730 ** Macros to determine if a column is hidden.  IsOrdinaryHiddenColumn()
1731 ** only works for non-virtual tables (ordinary tables and views) and is
1732 ** always false unless SQLITE_ENABLE_HIDDEN_COLUMNS is defined.  The
1733 ** IsHiddenColumn() macro is general purpose.
1734 */
1735 #if defined(SQLITE_ENABLE_HIDDEN_COLUMNS)
1736 #  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1737 #  define IsOrdinaryHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1738 #elif !defined(SQLITE_OMIT_VIRTUALTABLE)
1739 #  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1740 #  define IsOrdinaryHiddenColumn(X) 0
1741 #else
1742 #  define IsHiddenColumn(X)         0
1743 #  define IsOrdinaryHiddenColumn(X) 0
1744 #endif
1745 
1746 
1747 /* Does the table have a rowid */
1748 #define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
1749 #define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)
1750 
1751 /*
1752 ** Each foreign key constraint is an instance of the following structure.
1753 **
1754 ** A foreign key is associated with two tables.  The "from" table is
1755 ** the table that contains the REFERENCES clause that creates the foreign
1756 ** key.  The "to" table is the table that is named in the REFERENCES clause.
1757 ** Consider this example:
1758 **
1759 **     CREATE TABLE ex1(
1760 **       a INTEGER PRIMARY KEY,
1761 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
1762 **     );
1763 **
1764 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
1765 ** Equivalent names:
1766 **
1767 **     from-table == child-table
1768 **       to-table == parent-table
1769 **
1770 ** Each REFERENCES clause generates an instance of the following structure
1771 ** which is attached to the from-table.  The to-table need not exist when
1772 ** the from-table is created.  The existence of the to-table is not checked.
1773 **
1774 ** The list of all parents for child Table X is held at X.pFKey.
1775 **
1776 ** A list of all children for a table named Z (which might not even exist)
1777 ** is held in Schema.fkeyHash with a hash key of Z.
1778 */
1779 struct FKey {
1780   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
1781   FKey *pNextFrom;  /* Next FKey with the same in pFrom. Next parent of pFrom */
1782   char *zTo;        /* Name of table that the key points to (aka: Parent) */
1783   FKey *pNextTo;    /* Next with the same zTo. Next child of zTo. */
1784   FKey *pPrevTo;    /* Previous with the same zTo */
1785   int nCol;         /* Number of columns in this key */
1786   /* EV: R-30323-21917 */
1787   u8 isDeferred;       /* True if constraint checking is deferred till COMMIT */
1788   u8 aAction[2];        /* ON DELETE and ON UPDATE actions, respectively */
1789   Trigger *apTrigger[2];/* Triggers for aAction[] actions */
1790   struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
1791     int iFrom;            /* Index of column in pFrom */
1792     char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
1793   } aCol[1];            /* One entry for each of nCol columns */
1794 };
1795 
1796 /*
1797 ** SQLite supports many different ways to resolve a constraint
1798 ** error.  ROLLBACK processing means that a constraint violation
1799 ** causes the operation in process to fail and for the current transaction
1800 ** to be rolled back.  ABORT processing means the operation in process
1801 ** fails and any prior changes from that one operation are backed out,
1802 ** but the transaction is not rolled back.  FAIL processing means that
1803 ** the operation in progress stops and returns an error code.  But prior
1804 ** changes due to the same operation are not backed out and no rollback
1805 ** occurs.  IGNORE means that the particular row that caused the constraint
1806 ** error is not inserted or updated.  Processing continues and no error
1807 ** is returned.  REPLACE means that preexisting database rows that caused
1808 ** a UNIQUE constraint violation are removed so that the new insert or
1809 ** update can proceed.  Processing continues and no error is reported.
1810 **
1811 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
1812 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
1813 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
1814 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
1815 ** referenced table row is propagated into the row that holds the
1816 ** foreign key.
1817 **
1818 ** The following symbolic values are used to record which type
1819 ** of action to take.
1820 */
1821 #define OE_None     0   /* There is no constraint to check */
1822 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
1823 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
1824 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
1825 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
1826 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
1827 
1828 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
1829 #define OE_SetNull  7   /* Set the foreign key value to NULL */
1830 #define OE_SetDflt  8   /* Set the foreign key value to its default */
1831 #define OE_Cascade  9   /* Cascade the changes */
1832 
1833 #define OE_Default  10  /* Do whatever the default action is */
1834 
1835 
1836 /*
1837 ** An instance of the following structure is passed as the first
1838 ** argument to sqlite3VdbeKeyCompare and is used to control the
1839 ** comparison of the two index keys.
1840 **
1841 ** Note that aSortOrder[] and aColl[] have nField+1 slots.  There
1842 ** are nField slots for the columns of an index then one extra slot
1843 ** for the rowid at the end.
1844 */
1845 struct KeyInfo {
1846   u32 nRef;           /* Number of references to this KeyInfo object */
1847   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
1848   u16 nField;         /* Number of key columns in the index */
1849   u16 nXField;        /* Number of columns beyond the key columns */
1850   sqlite3 *db;        /* The database connection */
1851   u8 *aSortOrder;     /* Sort order for each column. */
1852   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
1853 };
1854 
1855 /*
1856 ** This object holds a record which has been parsed out into individual
1857 ** fields, for the purposes of doing a comparison.
1858 **
1859 ** A record is an object that contains one or more fields of data.
1860 ** Records are used to store the content of a table row and to store
1861 ** the key of an index.  A blob encoding of a record is created by
1862 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
1863 ** OP_Column opcode.
1864 **
1865 ** An instance of this object serves as a "key" for doing a search on
1866 ** an index b+tree. The goal of the search is to find the entry that
1867 ** is closed to the key described by this object.  This object might hold
1868 ** just a prefix of the key.  The number of fields is given by
1869 ** pKeyInfo->nField.
1870 **
1871 ** The r1 and r2 fields are the values to return if this key is less than
1872 ** or greater than a key in the btree, respectively.  These are normally
1873 ** -1 and +1 respectively, but might be inverted to +1 and -1 if the b-tree
1874 ** is in DESC order.
1875 **
1876 ** The key comparison functions actually return default_rc when they find
1877 ** an equals comparison.  default_rc can be -1, 0, or +1.  If there are
1878 ** multiple entries in the b-tree with the same key (when only looking
1879 ** at the first pKeyInfo->nFields,) then default_rc can be set to -1 to
1880 ** cause the search to find the last match, or +1 to cause the search to
1881 ** find the first match.
1882 **
1883 ** The key comparison functions will set eqSeen to true if they ever
1884 ** get and equal results when comparing this structure to a b-tree record.
1885 ** When default_rc!=0, the search might end up on the record immediately
1886 ** before the first match or immediately after the last match.  The
1887 ** eqSeen field will indicate whether or not an exact match exists in the
1888 ** b-tree.
1889 */
1890 struct UnpackedRecord {
1891   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
1892   Mem *aMem;          /* Values */
1893   u16 nField;         /* Number of entries in apMem[] */
1894   i8 default_rc;      /* Comparison result if keys are equal */
1895   u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
1896   i8 r1;              /* Value to return if (lhs > rhs) */
1897   i8 r2;              /* Value to return if (rhs < lhs) */
1898   u8 eqSeen;          /* True if an equality comparison has been seen */
1899 };
1900 
1901 
1902 /*
1903 ** Each SQL index is represented in memory by an
1904 ** instance of the following structure.
1905 **
1906 ** The columns of the table that are to be indexed are described
1907 ** by the aiColumn[] field of this structure.  For example, suppose
1908 ** we have the following table and index:
1909 **
1910 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
1911 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
1912 **
1913 ** In the Table structure describing Ex1, nCol==3 because there are
1914 ** three columns in the table.  In the Index structure describing
1915 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
1916 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
1917 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
1918 ** The second column to be indexed (c1) has an index of 0 in
1919 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
1920 **
1921 ** The Index.onError field determines whether or not the indexed columns
1922 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
1923 ** it means this is not a unique index.  Otherwise it is a unique index
1924 ** and the value of Index.onError indicate the which conflict resolution
1925 ** algorithm to employ whenever an attempt is made to insert a non-unique
1926 ** element.
1927 **
1928 ** While parsing a CREATE TABLE or CREATE INDEX statement in order to
1929 ** generate VDBE code (as opposed to parsing one read from an sqlite_master
1930 ** table as part of parsing an existing database schema), transient instances
1931 ** of this structure may be created. In this case the Index.tnum variable is
1932 ** used to store the address of a VDBE instruction, not a database page
1933 ** number (it cannot - the database page is not allocated until the VDBE
1934 ** program is executed). See convertToWithoutRowidTable() for details.
1935 */
1936 struct Index {
1937   char *zName;             /* Name of this index */
1938   i16 *aiColumn;           /* Which columns are used by this index.  1st is 0 */
1939   LogEst *aiRowLogEst;     /* From ANALYZE: Est. rows selected by each column */
1940   Table *pTable;           /* The SQL table being indexed */
1941   char *zColAff;           /* String defining the affinity of each column */
1942   Index *pNext;            /* The next index associated with the same table */
1943   Schema *pSchema;         /* Schema containing this index */
1944   u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
1945   const char **azColl;     /* Array of collation sequence names for index */
1946   Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
1947   ExprList *aColExpr;      /* Column expressions */
1948   int tnum;                /* DB Page containing root of this index */
1949   LogEst szIdxRow;         /* Estimated average row size in bytes */
1950   u16 nKeyCol;             /* Number of columns forming the key */
1951   u16 nColumn;             /* Number of columns stored in the index */
1952   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
1953   unsigned idxType:2;      /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
1954   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
1955   unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
1956   unsigned isResized:1;    /* True if resizeIndexObject() has been called */
1957   unsigned isCovering:1;   /* True if this is a covering index */
1958   unsigned noSkipScan:1;   /* Do not try to use skip-scan if true */
1959 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
1960   int nSample;             /* Number of elements in aSample[] */
1961   int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
1962   tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
1963   IndexSample *aSample;    /* Samples of the left-most key */
1964   tRowcnt *aiRowEst;       /* Non-logarithmic stat1 data for this index */
1965   tRowcnt nRowEst0;        /* Non-logarithmic number of rows in the index */
1966 #endif
1967 };
1968 
1969 /*
1970 ** Allowed values for Index.idxType
1971 */
1972 #define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
1973 #define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */
1974 #define SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */
1975 
1976 /* Return true if index X is a PRIMARY KEY index */
1977 #define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
1978 
1979 /* Return true if index X is a UNIQUE index */
1980 #define IsUniqueIndex(X)      ((X)->onError!=OE_None)
1981 
1982 /* The Index.aiColumn[] values are normally positive integer.  But
1983 ** there are some negative values that have special meaning:
1984 */
1985 #define XN_ROWID     (-1)     /* Indexed column is the rowid */
1986 #define XN_EXPR      (-2)     /* Indexed column is an expression */
1987 
1988 /*
1989 ** Each sample stored in the sqlite_stat3 table is represented in memory
1990 ** using a structure of this type.  See documentation at the top of the
1991 ** analyze.c source file for additional information.
1992 */
1993 struct IndexSample {
1994   void *p;          /* Pointer to sampled record */
1995   int n;            /* Size of record in bytes */
1996   tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
1997   tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
1998   tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
1999 };
2000 
2001 /*
2002 ** Each token coming out of the lexer is an instance of
2003 ** this structure.  Tokens are also used as part of an expression.
2004 **
2005 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
2006 ** may contain random values.  Do not make any assumptions about Token.dyn
2007 ** and Token.n when Token.z==0.
2008 */
2009 struct Token {
2010   const char *z;     /* Text of the token.  Not NULL-terminated! */
2011   unsigned int n;    /* Number of characters in this token */
2012 };
2013 
2014 /*
2015 ** An instance of this structure contains information needed to generate
2016 ** code for a SELECT that contains aggregate functions.
2017 **
2018 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
2019 ** pointer to this structure.  The Expr.iColumn field is the index in
2020 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
2021 ** code for that node.
2022 **
2023 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
2024 ** original Select structure that describes the SELECT statement.  These
2025 ** fields do not need to be freed when deallocating the AggInfo structure.
2026 */
2027 struct AggInfo {
2028   u8 directMode;          /* Direct rendering mode means take data directly
2029                           ** from source tables rather than from accumulators */
2030   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
2031                           ** than the source table */
2032   int sortingIdx;         /* Cursor number of the sorting index */
2033   int sortingIdxPTab;     /* Cursor number of pseudo-table */
2034   int nSortingColumn;     /* Number of columns in the sorting index */
2035   int mnReg, mxReg;       /* Range of registers allocated for aCol and aFunc */
2036   ExprList *pGroupBy;     /* The group by clause */
2037   struct AggInfo_col {    /* For each column used in source tables */
2038     Table *pTab;             /* Source table */
2039     int iTable;              /* Cursor number of the source table */
2040     int iColumn;             /* Column number within the source table */
2041     int iSorterColumn;       /* Column number in the sorting index */
2042     int iMem;                /* Memory location that acts as accumulator */
2043     Expr *pExpr;             /* The original expression */
2044   } *aCol;
2045   int nColumn;            /* Number of used entries in aCol[] */
2046   int nAccumulator;       /* Number of columns that show through to the output.
2047                           ** Additional columns are used only as parameters to
2048                           ** aggregate functions */
2049   struct AggInfo_func {   /* For each aggregate function */
2050     Expr *pExpr;             /* Expression encoding the function */
2051     FuncDef *pFunc;          /* The aggregate function implementation */
2052     int iMem;                /* Memory location that acts as accumulator */
2053     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
2054   } *aFunc;
2055   int nFunc;              /* Number of entries in aFunc[] */
2056 };
2057 
2058 /*
2059 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
2060 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
2061 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
2062 ** it uses less memory in the Expr object, which is a big memory user
2063 ** in systems with lots of prepared statements.  And few applications
2064 ** need more than about 10 or 20 variables.  But some extreme users want
2065 ** to have prepared statements with over 32767 variables, and for them
2066 ** the option is available (at compile-time).
2067 */
2068 #if SQLITE_MAX_VARIABLE_NUMBER<=32767
2069 typedef i16 ynVar;
2070 #else
2071 typedef int ynVar;
2072 #endif
2073 
2074 /*
2075 ** Each node of an expression in the parse tree is an instance
2076 ** of this structure.
2077 **
2078 ** Expr.op is the opcode. The integer parser token codes are reused
2079 ** as opcodes here. For example, the parser defines TK_GE to be an integer
2080 ** code representing the ">=" operator. This same integer code is reused
2081 ** to represent the greater-than-or-equal-to operator in the expression
2082 ** tree.
2083 **
2084 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
2085 ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
2086 ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
2087 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
2088 ** then Expr.token contains the name of the function.
2089 **
2090 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
2091 ** binary operator. Either or both may be NULL.
2092 **
2093 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
2094 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
2095 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
2096 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
2097 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
2098 ** valid.
2099 **
2100 ** An expression of the form ID or ID.ID refers to a column in a table.
2101 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
2102 ** the integer cursor number of a VDBE cursor pointing to that table and
2103 ** Expr.iColumn is the column number for the specific column.  If the
2104 ** expression is used as a result in an aggregate SELECT, then the
2105 ** value is also stored in the Expr.iAgg column in the aggregate so that
2106 ** it can be accessed after all aggregates are computed.
2107 **
2108 ** If the expression is an unbound variable marker (a question mark
2109 ** character '?' in the original SQL) then the Expr.iTable holds the index
2110 ** number for that variable.
2111 **
2112 ** If the expression is a subquery then Expr.iColumn holds an integer
2113 ** register number containing the result of the subquery.  If the
2114 ** subquery gives a constant result, then iTable is -1.  If the subquery
2115 ** gives a different answer at different times during statement processing
2116 ** then iTable is the address of a subroutine that computes the subquery.
2117 **
2118 ** If the Expr is of type OP_Column, and the table it is selecting from
2119 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
2120 ** corresponding table definition.
2121 **
2122 ** ALLOCATION NOTES:
2123 **
2124 ** Expr objects can use a lot of memory space in database schema.  To
2125 ** help reduce memory requirements, sometimes an Expr object will be
2126 ** truncated.  And to reduce the number of memory allocations, sometimes
2127 ** two or more Expr objects will be stored in a single memory allocation,
2128 ** together with Expr.zToken strings.
2129 **
2130 ** If the EP_Reduced and EP_TokenOnly flags are set when
2131 ** an Expr object is truncated.  When EP_Reduced is set, then all
2132 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
2133 ** are contained within the same memory allocation.  Note, however, that
2134 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
2135 ** allocated, regardless of whether or not EP_Reduced is set.
2136 */
2137 struct Expr {
2138   u8 op;                 /* Operation performed by this node */
2139   char affinity;         /* The affinity of the column or 0 if not a column */
2140   u32 flags;             /* Various flags.  EP_* See below */
2141   union {
2142     char *zToken;          /* Token value. Zero terminated and dequoted */
2143     int iValue;            /* Non-negative integer value if EP_IntValue */
2144   } u;
2145 
2146   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
2147   ** space is allocated for the fields below this point. An attempt to
2148   ** access them will result in a segfault or malfunction.
2149   *********************************************************************/
2150 
2151   Expr *pLeft;           /* Left subnode */
2152   Expr *pRight;          /* Right subnode */
2153   union {
2154     ExprList *pList;     /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
2155     Select *pSelect;     /* EP_xIsSelect and op = IN, EXISTS, SELECT */
2156   } x;
2157 
2158   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
2159   ** space is allocated for the fields below this point. An attempt to
2160   ** access them will result in a segfault or malfunction.
2161   *********************************************************************/
2162 
2163 #if SQLITE_MAX_EXPR_DEPTH>0
2164   int nHeight;           /* Height of the tree headed by this node */
2165 #endif
2166   int iTable;            /* TK_COLUMN: cursor number of table holding column
2167                          ** TK_REGISTER: register number
2168                          ** TK_TRIGGER: 1 -> new, 0 -> old
2169                          ** EP_Unlikely:  134217728 times likelihood */
2170   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
2171                          ** TK_VARIABLE: variable number (always >= 1). */
2172   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
2173   i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
2174   u8 op2;                /* TK_REGISTER: original value of Expr.op
2175                          ** TK_COLUMN: the value of p5 for OP_Column
2176                          ** TK_AGG_FUNCTION: nesting depth */
2177   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
2178   Table *pTab;           /* Table for TK_COLUMN expressions. */
2179 };
2180 
2181 /*
2182 ** The following are the meanings of bits in the Expr.flags field.
2183 */
2184 #define EP_FromJoin  0x000001 /* Originates in ON/USING clause of outer join */
2185 #define EP_Agg       0x000002 /* Contains one or more aggregate functions */
2186 #define EP_Resolved  0x000004 /* IDs have been resolved to COLUMNs */
2187 #define EP_Error     0x000008 /* Expression contains one or more errors */
2188 #define EP_Distinct  0x000010 /* Aggregate function with DISTINCT keyword */
2189 #define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
2190 #define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
2191 #define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
2192 #define EP_Collate   0x000100 /* Tree contains a TK_COLLATE operator */
2193 #define EP_Generic   0x000200 /* Ignore COLLATE or affinity on this tree */
2194 #define EP_IntValue  0x000400 /* Integer value contained in u.iValue */
2195 #define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
2196 #define EP_Skip      0x001000 /* COLLATE, AS, or UNLIKELY */
2197 #define EP_Reduced   0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
2198 #define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
2199 #define EP_Static    0x008000 /* Held in memory not obtained from malloc() */
2200 #define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
2201 #define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
2202 #define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
2203 #define EP_ConstFunc 0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
2204 #define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
2205 #define EP_Subquery  0x200000 /* Tree contains a TK_SELECT operator */
2206 #define EP_Alias     0x400000 /* Is an alias for a result set column */
2207 
2208 /*
2209 ** Combinations of two or more EP_* flags
2210 */
2211 #define EP_Propagate (EP_Collate|EP_Subquery) /* Propagate these bits up tree */
2212 
2213 /*
2214 ** These macros can be used to test, set, or clear bits in the
2215 ** Expr.flags field.
2216 */
2217 #define ExprHasProperty(E,P)     (((E)->flags&(P))!=0)
2218 #define ExprHasAllProperty(E,P)  (((E)->flags&(P))==(P))
2219 #define ExprSetProperty(E,P)     (E)->flags|=(P)
2220 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
2221 
2222 /* The ExprSetVVAProperty() macro is used for Verification, Validation,
2223 ** and Accreditation only.  It works like ExprSetProperty() during VVA
2224 ** processes but is a no-op for delivery.
2225 */
2226 #ifdef SQLITE_DEBUG
2227 # define ExprSetVVAProperty(E,P)  (E)->flags|=(P)
2228 #else
2229 # define ExprSetVVAProperty(E,P)
2230 #endif
2231 
2232 /*
2233 ** Macros to determine the number of bytes required by a normal Expr
2234 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
2235 ** and an Expr struct with the EP_TokenOnly flag set.
2236 */
2237 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
2238 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
2239 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
2240 
2241 /*
2242 ** Flags passed to the sqlite3ExprDup() function. See the header comment
2243 ** above sqlite3ExprDup() for details.
2244 */
2245 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
2246 
2247 /*
2248 ** A list of expressions.  Each expression may optionally have a
2249 ** name.  An expr/name combination can be used in several ways, such
2250 ** as the list of "expr AS ID" fields following a "SELECT" or in the
2251 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
2252 ** also be used as the argument to a function, in which case the a.zName
2253 ** field is not used.
2254 **
2255 ** By default the Expr.zSpan field holds a human-readable description of
2256 ** the expression that is used in the generation of error messages and
2257 ** column labels.  In this case, Expr.zSpan is typically the text of a
2258 ** column expression as it exists in a SELECT statement.  However, if
2259 ** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
2260 ** of the result column in the form: DATABASE.TABLE.COLUMN.  This later
2261 ** form is used for name resolution with nested FROM clauses.
2262 */
2263 struct ExprList {
2264   int nExpr;             /* Number of expressions on the list */
2265   struct ExprList_item { /* For each expression in the list */
2266     Expr *pExpr;            /* The list of expressions */
2267     char *zName;            /* Token associated with this expression */
2268     char *zSpan;            /* Original text of the expression */
2269     u8 sortOrder;           /* 1 for DESC or 0 for ASC */
2270     unsigned done :1;       /* A flag to indicate when processing is finished */
2271     unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
2272     unsigned reusable :1;   /* Constant expression is reusable */
2273     union {
2274       struct {
2275         u16 iOrderByCol;      /* For ORDER BY, column number in result set */
2276         u16 iAlias;           /* Index into Parse.aAlias[] for zName */
2277       } x;
2278       int iConstExprReg;      /* Register in which Expr value is cached */
2279     } u;
2280   } *a;                  /* Alloc a power of two greater or equal to nExpr */
2281 };
2282 
2283 /*
2284 ** An instance of this structure is used by the parser to record both
2285 ** the parse tree for an expression and the span of input text for an
2286 ** expression.
2287 */
2288 struct ExprSpan {
2289   Expr *pExpr;          /* The expression parse tree */
2290   const char *zStart;   /* First character of input text */
2291   const char *zEnd;     /* One character past the end of input text */
2292 };
2293 
2294 /*
2295 ** An instance of this structure can hold a simple list of identifiers,
2296 ** such as the list "a,b,c" in the following statements:
2297 **
2298 **      INSERT INTO t(a,b,c) VALUES ...;
2299 **      CREATE INDEX idx ON t(a,b,c);
2300 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
2301 **
2302 ** The IdList.a.idx field is used when the IdList represents the list of
2303 ** column names after a table name in an INSERT statement.  In the statement
2304 **
2305 **     INSERT INTO t(a,b,c) ...
2306 **
2307 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
2308 */
2309 struct IdList {
2310   struct IdList_item {
2311     char *zName;      /* Name of the identifier */
2312     int idx;          /* Index in some Table.aCol[] of a column named zName */
2313   } *a;
2314   int nId;         /* Number of identifiers on the list */
2315 };
2316 
2317 /*
2318 ** The bitmask datatype defined below is used for various optimizations.
2319 **
2320 ** Changing this from a 64-bit to a 32-bit type limits the number of
2321 ** tables in a join to 32 instead of 64.  But it also reduces the size
2322 ** of the library by 738 bytes on ix86.
2323 */
2324 typedef u64 Bitmask;
2325 
2326 /*
2327 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
2328 */
2329 #define BMS  ((int)(sizeof(Bitmask)*8))
2330 
2331 /*
2332 ** A bit in a Bitmask
2333 */
2334 #define MASKBIT(n)   (((Bitmask)1)<<(n))
2335 #define MASKBIT32(n) (((unsigned int)1)<<(n))
2336 
2337 /*
2338 ** The following structure describes the FROM clause of a SELECT statement.
2339 ** Each table or subquery in the FROM clause is a separate element of
2340 ** the SrcList.a[] array.
2341 **
2342 ** With the addition of multiple database support, the following structure
2343 ** can also be used to describe a particular table such as the table that
2344 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
2345 ** such a table must be a simple name: ID.  But in SQLite, the table can
2346 ** now be identified by a database name, a dot, then the table name: ID.ID.
2347 **
2348 ** The jointype starts out showing the join type between the current table
2349 ** and the next table on the list.  The parser builds the list this way.
2350 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
2351 ** jointype expresses the join between the table and the previous table.
2352 **
2353 ** In the colUsed field, the high-order bit (bit 63) is set if the table
2354 ** contains more than 63 columns and the 64-th or later column is used.
2355 */
2356 struct SrcList {
2357   int nSrc;        /* Number of tables or subqueries in the FROM clause */
2358   u32 nAlloc;      /* Number of entries allocated in a[] below */
2359   struct SrcList_item {
2360     Schema *pSchema;  /* Schema to which this item is fixed */
2361     char *zDatabase;  /* Name of database holding this table */
2362     char *zName;      /* Name of the table */
2363     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
2364     Table *pTab;      /* An SQL table corresponding to zName */
2365     Select *pSelect;  /* A SELECT statement used in place of a table name */
2366     int addrFillSub;  /* Address of subroutine to manifest a subquery */
2367     int regReturn;    /* Register holding return address of addrFillSub */
2368     int regResult;    /* Registers holding results of a co-routine */
2369     struct {
2370       u8 jointype;      /* Type of join between this able and the previous */
2371       unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
2372       unsigned isIndexedBy :1;   /* True if there is an INDEXED BY clause */
2373       unsigned isTabFunc :1;     /* True if table-valued-function syntax */
2374       unsigned isCorrelated :1;  /* True if sub-query is correlated */
2375       unsigned viaCoroutine :1;  /* Implemented as a co-routine */
2376       unsigned isRecursive :1;   /* True for recursive reference in WITH */
2377     } fg;
2378 #ifndef SQLITE_OMIT_EXPLAIN
2379     u8 iSelectId;     /* If pSelect!=0, the id of the sub-select in EQP */
2380 #endif
2381     int iCursor;      /* The VDBE cursor number used to access this table */
2382     Expr *pOn;        /* The ON clause of a join */
2383     IdList *pUsing;   /* The USING clause of a join */
2384     Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
2385     union {
2386       char *zIndexedBy;    /* Identifier from "INDEXED BY <zIndex>" clause */
2387       ExprList *pFuncArg;  /* Arguments to table-valued-function */
2388     } u1;
2389     Index *pIBIndex;  /* Index structure corresponding to u1.zIndexedBy */
2390   } a[1];             /* One entry for each identifier on the list */
2391 };
2392 
2393 /*
2394 ** Permitted values of the SrcList.a.jointype field
2395 */
2396 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
2397 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
2398 #define JT_NATURAL   0x0004    /* True for a "natural" join */
2399 #define JT_LEFT      0x0008    /* Left outer join */
2400 #define JT_RIGHT     0x0010    /* Right outer join */
2401 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
2402 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
2403 
2404 
2405 /*
2406 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
2407 ** and the WhereInfo.wctrlFlags member.
2408 */
2409 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
2410 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
2411 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
2412 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
2413 #define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
2414 #define WHERE_OMIT_OPEN_CLOSE  0x0010 /* Table cursors are already open */
2415 #define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
2416 #define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
2417 #define WHERE_NO_AUTOINDEX     0x0080 /* Disallow automatic indexes */
2418 #define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
2419 #define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
2420 #define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
2421 #define WHERE_SORTBYGROUP      0x0800 /* Support sqlite3WhereIsSorted() */
2422 #define WHERE_REOPEN_IDX       0x1000 /* Try to use OP_ReopenIdx */
2423 #define WHERE_ONEPASS_MULTIROW 0x2000 /* ONEPASS is ok with multiple rows */
2424 
2425 /* Allowed return values from sqlite3WhereIsDistinct()
2426 */
2427 #define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
2428 #define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
2429 #define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
2430 #define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
2431 
2432 /*
2433 ** A NameContext defines a context in which to resolve table and column
2434 ** names.  The context consists of a list of tables (the pSrcList) field and
2435 ** a list of named expression (pEList).  The named expression list may
2436 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
2437 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
2438 ** pEList corresponds to the result set of a SELECT and is NULL for
2439 ** other statements.
2440 **
2441 ** NameContexts can be nested.  When resolving names, the inner-most
2442 ** context is searched first.  If no match is found, the next outer
2443 ** context is checked.  If there is still no match, the next context
2444 ** is checked.  This process continues until either a match is found
2445 ** or all contexts are check.  When a match is found, the nRef member of
2446 ** the context containing the match is incremented.
2447 **
2448 ** Each subquery gets a new NameContext.  The pNext field points to the
2449 ** NameContext in the parent query.  Thus the process of scanning the
2450 ** NameContext list corresponds to searching through successively outer
2451 ** subqueries looking for a match.
2452 */
2453 struct NameContext {
2454   Parse *pParse;       /* The parser */
2455   SrcList *pSrcList;   /* One or more tables used to resolve names */
2456   ExprList *pEList;    /* Optional list of result-set columns */
2457   AggInfo *pAggInfo;   /* Information about aggregates at this level */
2458   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
2459   int nRef;            /* Number of names resolved by this context */
2460   int nErr;            /* Number of errors encountered while resolving names */
2461   u16 ncFlags;         /* Zero or more NC_* flags defined below */
2462 };
2463 
2464 /*
2465 ** Allowed values for the NameContext, ncFlags field.
2466 **
2467 ** Note:  NC_MinMaxAgg must have the same value as SF_MinMaxAgg and
2468 ** SQLITE_FUNC_MINMAX.
2469 **
2470 */
2471 #define NC_AllowAgg  0x0001  /* Aggregate functions are allowed here */
2472 #define NC_HasAgg    0x0002  /* One or more aggregate functions seen */
2473 #define NC_IsCheck   0x0004  /* True if resolving names in a CHECK constraint */
2474 #define NC_InAggFunc 0x0008  /* True if analyzing arguments to an agg func */
2475 #define NC_PartIdx   0x0010  /* True if resolving a partial index WHERE */
2476 #define NC_IdxExpr   0x0020  /* True if resolving columns of CREATE INDEX */
2477 #define NC_MinMaxAgg 0x1000  /* min/max aggregates seen.  See note above */
2478 
2479 /*
2480 ** An instance of the following structure contains all information
2481 ** needed to generate code for a single SELECT statement.
2482 **
2483 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
2484 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
2485 ** limit and nOffset to the value of the offset (or 0 if there is not
2486 ** offset).  But later on, nLimit and nOffset become the memory locations
2487 ** in the VDBE that record the limit and offset counters.
2488 **
2489 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
2490 ** These addresses must be stored so that we can go back and fill in
2491 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
2492 ** the number of columns in P2 can be computed at the same time
2493 ** as the OP_OpenEphm instruction is coded because not
2494 ** enough information about the compound query is known at that point.
2495 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
2496 ** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
2497 ** sequences for the ORDER BY clause.
2498 */
2499 struct Select {
2500   ExprList *pEList;      /* The fields of the result */
2501   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
2502   u16 selFlags;          /* Various SF_* values */
2503   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
2504 #if SELECTTRACE_ENABLED
2505   char zSelName[12];     /* Symbolic name of this SELECT use for debugging */
2506 #endif
2507   int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
2508   u64 nSelectRow;        /* Estimated number of result rows */
2509   SrcList *pSrc;         /* The FROM clause */
2510   Expr *pWhere;          /* The WHERE clause */
2511   ExprList *pGroupBy;    /* The GROUP BY clause */
2512   Expr *pHaving;         /* The HAVING clause */
2513   ExprList *pOrderBy;    /* The ORDER BY clause */
2514   Select *pPrior;        /* Prior select in a compound select statement */
2515   Select *pNext;         /* Next select to the left in a compound */
2516   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
2517   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
2518   With *pWith;           /* WITH clause attached to this select. Or NULL. */
2519 };
2520 
2521 /*
2522 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
2523 ** "Select Flag".
2524 */
2525 #define SF_Distinct        0x0001  /* Output should be DISTINCT */
2526 #define SF_All             0x0002  /* Includes the ALL keyword */
2527 #define SF_Resolved        0x0004  /* Identifiers have been resolved */
2528 #define SF_Aggregate       0x0008  /* Contains aggregate functions */
2529 #define SF_UsesEphemeral   0x0010  /* Uses the OpenEphemeral opcode */
2530 #define SF_Expanded        0x0020  /* sqlite3SelectExpand() called on this */
2531 #define SF_HasTypeInfo     0x0040  /* FROM subqueries have Table metadata */
2532 #define SF_Compound        0x0080  /* Part of a compound query */
2533 #define SF_Values          0x0100  /* Synthesized from VALUES clause */
2534 #define SF_MultiValue      0x0200  /* Single VALUES term with multiple rows */
2535 #define SF_NestedFrom      0x0400  /* Part of a parenthesized FROM clause */
2536 #define SF_MaybeConvert    0x0800  /* Need convertCompoundSelectToSubquery() */
2537 #define SF_MinMaxAgg       0x1000  /* Aggregate containing min() or max() */
2538 #define SF_Recursive       0x2000  /* The recursive part of a recursive CTE */
2539 #define SF_Converted       0x4000  /* By convertCompoundSelectToSubquery() */
2540 #define SF_IncludeHidden   0x8000  /* Include hidden columns in output */
2541 
2542 
2543 /*
2544 ** The results of a SELECT can be distributed in several ways, as defined
2545 ** by one of the following macros.  The "SRT" prefix means "SELECT Result
2546 ** Type".
2547 **
2548 **     SRT_Union       Store results as a key in a temporary index
2549 **                     identified by pDest->iSDParm.
2550 **
2551 **     SRT_Except      Remove results from the temporary index pDest->iSDParm.
2552 **
2553 **     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
2554 **                     set is not empty.
2555 **
2556 **     SRT_Discard     Throw the results away.  This is used by SELECT
2557 **                     statements within triggers whose only purpose is
2558 **                     the side-effects of functions.
2559 **
2560 ** All of the above are free to ignore their ORDER BY clause. Those that
2561 ** follow must honor the ORDER BY clause.
2562 **
2563 **     SRT_Output      Generate a row of output (using the OP_ResultRow
2564 **                     opcode) for each row in the result set.
2565 **
2566 **     SRT_Mem         Only valid if the result is a single column.
2567 **                     Store the first column of the first result row
2568 **                     in register pDest->iSDParm then abandon the rest
2569 **                     of the query.  This destination implies "LIMIT 1".
2570 **
2571 **     SRT_Set         The result must be a single column.  Store each
2572 **                     row of result as the key in table pDest->iSDParm.
2573 **                     Apply the affinity pDest->affSdst before storing
2574 **                     results.  Used to implement "IN (SELECT ...)".
2575 **
2576 **     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
2577 **                     the result there. The cursor is left open after
2578 **                     returning.  This is like SRT_Table except that
2579 **                     this destination uses OP_OpenEphemeral to create
2580 **                     the table first.
2581 **
2582 **     SRT_Coroutine   Generate a co-routine that returns a new row of
2583 **                     results each time it is invoked.  The entry point
2584 **                     of the co-routine is stored in register pDest->iSDParm
2585 **                     and the result row is stored in pDest->nDest registers
2586 **                     starting with pDest->iSdst.
2587 **
2588 **     SRT_Table       Store results in temporary table pDest->iSDParm.
2589 **     SRT_Fifo        This is like SRT_EphemTab except that the table
2590 **                     is assumed to already be open.  SRT_Fifo has
2591 **                     the additional property of being able to ignore
2592 **                     the ORDER BY clause.
2593 **
2594 **     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
2595 **                     But also use temporary table pDest->iSDParm+1 as
2596 **                     a record of all prior results and ignore any duplicate
2597 **                     rows.  Name means:  "Distinct Fifo".
2598 **
2599 **     SRT_Queue       Store results in priority queue pDest->iSDParm (really
2600 **                     an index).  Append a sequence number so that all entries
2601 **                     are distinct.
2602 **
2603 **     SRT_DistQueue   Store results in priority queue pDest->iSDParm only if
2604 **                     the same record has never been stored before.  The
2605 **                     index at pDest->iSDParm+1 hold all prior stores.
2606 */
2607 #define SRT_Union        1  /* Store result as keys in an index */
2608 #define SRT_Except       2  /* Remove result from a UNION index */
2609 #define SRT_Exists       3  /* Store 1 if the result is not empty */
2610 #define SRT_Discard      4  /* Do not save the results anywhere */
2611 #define SRT_Fifo         5  /* Store result as data with an automatic rowid */
2612 #define SRT_DistFifo     6  /* Like SRT_Fifo, but unique results only */
2613 #define SRT_Queue        7  /* Store result in an queue */
2614 #define SRT_DistQueue    8  /* Like SRT_Queue, but unique results only */
2615 
2616 /* The ORDER BY clause is ignored for all of the above */
2617 #define IgnorableOrderby(X) ((X->eDest)<=SRT_DistQueue)
2618 
2619 #define SRT_Output       9  /* Output each row of result */
2620 #define SRT_Mem         10  /* Store result in a memory cell */
2621 #define SRT_Set         11  /* Store results as keys in an index */
2622 #define SRT_EphemTab    12  /* Create transient tab and store like SRT_Table */
2623 #define SRT_Coroutine   13  /* Generate a single row of result */
2624 #define SRT_Table       14  /* Store result as data with an automatic rowid */
2625 
2626 /*
2627 ** An instance of this object describes where to put of the results of
2628 ** a SELECT statement.
2629 */
2630 struct SelectDest {
2631   u8 eDest;            /* How to dispose of the results.  On of SRT_* above. */
2632   char affSdst;        /* Affinity used when eDest==SRT_Set */
2633   int iSDParm;         /* A parameter used by the eDest disposal method */
2634   int iSdst;           /* Base register where results are written */
2635   int nSdst;           /* Number of registers allocated */
2636   ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
2637 };
2638 
2639 /*
2640 ** During code generation of statements that do inserts into AUTOINCREMENT
2641 ** tables, the following information is attached to the Table.u.autoInc.p
2642 ** pointer of each autoincrement table to record some side information that
2643 ** the code generator needs.  We have to keep per-table autoincrement
2644 ** information in case inserts are down within triggers.  Triggers do not
2645 ** normally coordinate their activities, but we do need to coordinate the
2646 ** loading and saving of autoincrement information.
2647 */
2648 struct AutoincInfo {
2649   AutoincInfo *pNext;   /* Next info block in a list of them all */
2650   Table *pTab;          /* Table this info block refers to */
2651   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
2652   int regCtr;           /* Memory register holding the rowid counter */
2653 };
2654 
2655 /*
2656 ** Size of the column cache
2657 */
2658 #ifndef SQLITE_N_COLCACHE
2659 # define SQLITE_N_COLCACHE 10
2660 #endif
2661 
2662 /*
2663 ** At least one instance of the following structure is created for each
2664 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
2665 ** statement. All such objects are stored in the linked list headed at
2666 ** Parse.pTriggerPrg and deleted once statement compilation has been
2667 ** completed.
2668 **
2669 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
2670 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
2671 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
2672 ** The Parse.pTriggerPrg list never contains two entries with the same
2673 ** values for both pTrigger and orconf.
2674 **
2675 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
2676 ** accessed (or set to 0 for triggers fired as a result of INSERT
2677 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
2678 ** a mask of new.* columns used by the program.
2679 */
2680 struct TriggerPrg {
2681   Trigger *pTrigger;      /* Trigger this program was coded from */
2682   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
2683   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
2684   int orconf;             /* Default ON CONFLICT policy */
2685   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
2686 };
2687 
2688 /*
2689 ** The yDbMask datatype for the bitmask of all attached databases.
2690 */
2691 #if SQLITE_MAX_ATTACHED>30
2692   typedef unsigned char yDbMask[(SQLITE_MAX_ATTACHED+9)/8];
2693 # define DbMaskTest(M,I)    (((M)[(I)/8]&(1<<((I)&7)))!=0)
2694 # define DbMaskZero(M)      memset((M),0,sizeof(M))
2695 # define DbMaskSet(M,I)     (M)[(I)/8]|=(1<<((I)&7))
2696 # define DbMaskAllZero(M)   sqlite3DbMaskAllZero(M)
2697 # define DbMaskNonZero(M)   (sqlite3DbMaskAllZero(M)==0)
2698 #else
2699   typedef unsigned int yDbMask;
2700 # define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
2701 # define DbMaskZero(M)      (M)=0
2702 # define DbMaskSet(M,I)     (M)|=(((yDbMask)1)<<(I))
2703 # define DbMaskAllZero(M)   (M)==0
2704 # define DbMaskNonZero(M)   (M)!=0
2705 #endif
2706 
2707 /*
2708 ** An SQL parser context.  A copy of this structure is passed through
2709 ** the parser and down into all the parser action routine in order to
2710 ** carry around information that is global to the entire parse.
2711 **
2712 ** The structure is divided into two parts.  When the parser and code
2713 ** generate call themselves recursively, the first part of the structure
2714 ** is constant but the second part is reset at the beginning and end of
2715 ** each recursion.
2716 **
2717 ** The nTableLock and aTableLock variables are only used if the shared-cache
2718 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
2719 ** used to store the set of table-locks required by the statement being
2720 ** compiled. Function sqlite3TableLock() is used to add entries to the
2721 ** list.
2722 */
2723 struct Parse {
2724   sqlite3 *db;         /* The main database structure */
2725   char *zErrMsg;       /* An error message */
2726   Vdbe *pVdbe;         /* An engine for executing database bytecode */
2727   int rc;              /* Return code from execution */
2728   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
2729   u8 checkSchema;      /* Causes schema cookie check after an error */
2730   u8 nested;           /* Number of nested calls to the parser/code generator */
2731   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
2732   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
2733   u8 mayAbort;         /* True if statement may throw an ABORT exception */
2734   u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
2735   u8 okConstFactor;    /* OK to factor out constants */
2736   int aTempReg[8];     /* Holding area for temporary registers */
2737   int nRangeReg;       /* Size of the temporary register block */
2738   int iRangeReg;       /* First register in temporary register block */
2739   int nErr;            /* Number of errors seen */
2740   int nTab;            /* Number of previously allocated VDBE cursors */
2741   int nMem;            /* Number of memory cells used so far */
2742   int nSet;            /* Number of sets used so far */
2743   int nOnce;           /* Number of OP_Once instructions so far */
2744   int nOpAlloc;        /* Number of slots allocated for Vdbe.aOp[] */
2745   int szOpAlloc;       /* Bytes of memory space allocated for Vdbe.aOp[] */
2746   int iFixedOp;        /* Never back out opcodes iFixedOp-1 or earlier */
2747   int ckBase;          /* Base register of data during check constraints */
2748   int iSelfTab;        /* Table of an index whose exprs are being coded */
2749   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
2750   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
2751   int nLabel;          /* Number of labels used */
2752   int *aLabel;         /* Space to hold the labels */
2753   struct yColCache {
2754     int iTable;           /* Table cursor number */
2755     i16 iColumn;          /* Table column number */
2756     u8 tempReg;           /* iReg is a temp register that needs to be freed */
2757     int iLevel;           /* Nesting level */
2758     int iReg;             /* Reg with value of this column. 0 means none. */
2759     int lru;              /* Least recently used entry has the smallest value */
2760   } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
2761   ExprList *pConstExpr;/* Constant expressions */
2762   Token constraintName;/* Name of the constraint currently being parsed */
2763   yDbMask writeMask;   /* Start a write transaction on these databases */
2764   yDbMask cookieMask;  /* Bitmask of schema verified databases */
2765   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
2766   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
2767   int regRoot;         /* Register holding root page number for new objects */
2768   int nMaxArg;         /* Max args passed to user function by sub-program */
2769 #if SELECTTRACE_ENABLED
2770   int nSelect;         /* Number of SELECT statements seen */
2771   int nSelectIndent;   /* How far to indent SELECTTRACE() output */
2772 #endif
2773 #ifndef SQLITE_OMIT_SHARED_CACHE
2774   int nTableLock;        /* Number of locks in aTableLock */
2775   TableLock *aTableLock; /* Required table locks for shared-cache mode */
2776 #endif
2777   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
2778 
2779   /* Information used while coding trigger programs. */
2780   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
2781   Table *pTriggerTab;  /* Table triggers are being coded for */
2782   int addrCrTab;       /* Address of OP_CreateTable opcode on CREATE TABLE */
2783   u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
2784   u32 oldmask;         /* Mask of old.* columns referenced */
2785   u32 newmask;         /* Mask of new.* columns referenced */
2786   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
2787   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
2788   u8 disableTriggers;  /* True to disable triggers */
2789 
2790   /************************************************************************
2791   ** Above is constant between recursions.  Below is reset before and after
2792   ** each recursion.  The boundary between these two regions is determined
2793   ** using offsetof(Parse,nVar) so the nVar field must be the first field
2794   ** in the recursive region.
2795   ************************************************************************/
2796 
2797   ynVar nVar;               /* Number of '?' variables seen in the SQL so far */
2798   int nzVar;                /* Number of available slots in azVar[] */
2799   u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
2800   u8 explain;               /* True if the EXPLAIN flag is found on the query */
2801 #ifndef SQLITE_OMIT_VIRTUALTABLE
2802   u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
2803   int nVtabLock;            /* Number of virtual tables to lock */
2804 #endif
2805   int nAlias;               /* Number of aliased result set columns */
2806   int nHeight;              /* Expression tree height of current sub-select */
2807 #ifndef SQLITE_OMIT_EXPLAIN
2808   int iSelectId;            /* ID of current select for EXPLAIN output */
2809   int iNextSelectId;        /* Next available select ID for EXPLAIN output */
2810 #endif
2811   char **azVar;             /* Pointers to names of parameters */
2812   Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
2813   const char *zTail;        /* All SQL text past the last semicolon parsed */
2814   Table *pNewTable;         /* A table being constructed by CREATE TABLE */
2815   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
2816   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
2817   Token sNameToken;         /* Token with unqualified schema object name */
2818   Token sLastToken;         /* The last token parsed */
2819 #ifndef SQLITE_OMIT_VIRTUALTABLE
2820   Token sArg;               /* Complete text of a module argument */
2821   Table **apVtabLock;       /* Pointer to virtual tables needing locking */
2822 #endif
2823   Table *pZombieTab;        /* List of Table objects to delete after code gen */
2824   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
2825   With *pWith;              /* Current WITH clause, or NULL */
2826   With *pWithToFree;        /* Free this WITH object at the end of the parse */
2827 };
2828 
2829 /*
2830 ** Return true if currently inside an sqlite3_declare_vtab() call.
2831 */
2832 #ifdef SQLITE_OMIT_VIRTUALTABLE
2833   #define IN_DECLARE_VTAB 0
2834 #else
2835   #define IN_DECLARE_VTAB (pParse->declareVtab)
2836 #endif
2837 
2838 /*
2839 ** An instance of the following structure can be declared on a stack and used
2840 ** to save the Parse.zAuthContext value so that it can be restored later.
2841 */
2842 struct AuthContext {
2843   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
2844   Parse *pParse;              /* The Parse structure */
2845 };
2846 
2847 /*
2848 ** Bitfield flags for P5 value in various opcodes.
2849 */
2850 #define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
2851 #define OPFLAG_EPHEM         0x01    /* OP_Column: Ephemeral output is ok */
2852 #define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
2853 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
2854 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
2855 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
2856 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
2857 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
2858 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
2859 #define OPFLAG_SEEKEQ        0x02    /* OP_Open** cursor uses EQ seek only */
2860 #define OPFLAG_FORDELETE     0x08    /* OP_Open should use BTREE_FORDELETE */
2861 #define OPFLAG_P2ISREG       0x10    /* P2 to OP_Open** is a register number */
2862 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
2863 
2864 /*
2865  * Each trigger present in the database schema is stored as an instance of
2866  * struct Trigger.
2867  *
2868  * Pointers to instances of struct Trigger are stored in two ways.
2869  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
2870  *    database). This allows Trigger structures to be retrieved by name.
2871  * 2. All triggers associated with a single table form a linked list, using the
2872  *    pNext member of struct Trigger. A pointer to the first element of the
2873  *    linked list is stored as the "pTrigger" member of the associated
2874  *    struct Table.
2875  *
2876  * The "step_list" member points to the first element of a linked list
2877  * containing the SQL statements specified as the trigger program.
2878  */
2879 struct Trigger {
2880   char *zName;            /* The name of the trigger                        */
2881   char *table;            /* The table or view to which the trigger applies */
2882   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
2883   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
2884   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
2885   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
2886                              the <column-list> is stored here */
2887   Schema *pSchema;        /* Schema containing the trigger */
2888   Schema *pTabSchema;     /* Schema containing the table */
2889   TriggerStep *step_list; /* Link list of trigger program steps             */
2890   Trigger *pNext;         /* Next trigger associated with the table */
2891 };
2892 
2893 /*
2894 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
2895 ** determine which.
2896 **
2897 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
2898 ** In that cases, the constants below can be ORed together.
2899 */
2900 #define TRIGGER_BEFORE  1
2901 #define TRIGGER_AFTER   2
2902 
2903 /*
2904  * An instance of struct TriggerStep is used to store a single SQL statement
2905  * that is a part of a trigger-program.
2906  *
2907  * Instances of struct TriggerStep are stored in a singly linked list (linked
2908  * using the "pNext" member) referenced by the "step_list" member of the
2909  * associated struct Trigger instance. The first element of the linked list is
2910  * the first step of the trigger-program.
2911  *
2912  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
2913  * "SELECT" statement. The meanings of the other members is determined by the
2914  * value of "op" as follows:
2915  *
2916  * (op == TK_INSERT)
2917  * orconf    -> stores the ON CONFLICT algorithm
2918  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
2919  *              this stores a pointer to the SELECT statement. Otherwise NULL.
2920  * zTarget   -> Dequoted name of the table to insert into.
2921  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
2922  *              this stores values to be inserted. Otherwise NULL.
2923  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
2924  *              statement, then this stores the column-names to be
2925  *              inserted into.
2926  *
2927  * (op == TK_DELETE)
2928  * zTarget   -> Dequoted name of the table to delete from.
2929  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
2930  *              Otherwise NULL.
2931  *
2932  * (op == TK_UPDATE)
2933  * zTarget   -> Dequoted name of the table to update.
2934  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
2935  *              Otherwise NULL.
2936  * pExprList -> A list of the columns to update and the expressions to update
2937  *              them to. See sqlite3Update() documentation of "pChanges"
2938  *              argument.
2939  *
2940  */
2941 struct TriggerStep {
2942   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
2943   u8 orconf;           /* OE_Rollback etc. */
2944   Trigger *pTrig;      /* The trigger that this step is a part of */
2945   Select *pSelect;     /* SELECT statement or RHS of INSERT INTO SELECT ... */
2946   char *zTarget;       /* Target table for DELETE, UPDATE, INSERT */
2947   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
2948   ExprList *pExprList; /* SET clause for UPDATE. */
2949   IdList *pIdList;     /* Column names for INSERT */
2950   TriggerStep *pNext;  /* Next in the link-list */
2951   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
2952 };
2953 
2954 /*
2955 ** The following structure contains information used by the sqliteFix...
2956 ** routines as they walk the parse tree to make database references
2957 ** explicit.
2958 */
2959 typedef struct DbFixer DbFixer;
2960 struct DbFixer {
2961   Parse *pParse;      /* The parsing context.  Error messages written here */
2962   Schema *pSchema;    /* Fix items to this schema */
2963   int bVarOnly;       /* Check for variable references only */
2964   const char *zDb;    /* Make sure all objects are contained in this database */
2965   const char *zType;  /* Type of the container - used for error messages */
2966   const Token *pName; /* Name of the container - used for error messages */
2967 };
2968 
2969 /*
2970 ** An objected used to accumulate the text of a string where we
2971 ** do not necessarily know how big the string will be in the end.
2972 */
2973 struct StrAccum {
2974   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
2975   char *zBase;         /* A base allocation.  Not from malloc. */
2976   char *zText;         /* The string collected so far */
2977   u32  nChar;          /* Length of the string so far */
2978   u32  nAlloc;         /* Amount of space allocated in zText */
2979   u32  mxAlloc;        /* Maximum allowed allocation.  0 for no malloc usage */
2980   u8   accError;       /* STRACCUM_NOMEM or STRACCUM_TOOBIG */
2981   u8   bMalloced;      /* zText points to allocated space */
2982 };
2983 #define STRACCUM_NOMEM   1
2984 #define STRACCUM_TOOBIG  2
2985 
2986 /*
2987 ** A pointer to this structure is used to communicate information
2988 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
2989 */
2990 typedef struct {
2991   sqlite3 *db;        /* The database being initialized */
2992   char **pzErrMsg;    /* Error message stored here */
2993   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
2994   int rc;             /* Result code stored here */
2995 } InitData;
2996 
2997 /*
2998 ** Structure containing global configuration data for the SQLite library.
2999 **
3000 ** This structure also contains some state information.
3001 */
3002 struct Sqlite3Config {
3003   int bMemstat;                     /* True to enable memory status */
3004   int bCoreMutex;                   /* True to enable core mutexing */
3005   int bFullMutex;                   /* True to enable full mutexing */
3006   int bOpenUri;                     /* True to interpret filenames as URIs */
3007   int bUseCis;                      /* Use covering indices for full-scans */
3008   int mxStrlen;                     /* Maximum string length */
3009   int neverCorrupt;                 /* Database is always well-formed */
3010   int szLookaside;                  /* Default lookaside buffer size */
3011   int nLookaside;                   /* Default lookaside buffer count */
3012   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
3013   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
3014   sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
3015   void *pHeap;                      /* Heap storage space */
3016   int nHeap;                        /* Size of pHeap[] */
3017   int mnReq, mxReq;                 /* Min and max heap requests sizes */
3018   sqlite3_int64 szMmap;             /* mmap() space per open file */
3019   sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
3020   void *pScratch;                   /* Scratch memory */
3021   int szScratch;                    /* Size of each scratch buffer */
3022   int nScratch;                     /* Number of scratch buffers */
3023   void *pPage;                      /* Page cache memory */
3024   int szPage;                       /* Size of each page in pPage[] */
3025   int nPage;                        /* Number of pages in pPage[] */
3026   int mxParserStack;                /* maximum depth of the parser stack */
3027   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
3028   u32 szPma;                        /* Maximum Sorter PMA size */
3029   /* The above might be initialized to non-zero.  The following need to always
3030   ** initially be zero, however. */
3031   int isInit;                       /* True after initialization has finished */
3032   int inProgress;                   /* True while initialization in progress */
3033   int isMutexInit;                  /* True after mutexes are initialized */
3034   int isMallocInit;                 /* True after malloc is initialized */
3035   int isPCacheInit;                 /* True after malloc is initialized */
3036   int nRefInitMutex;                /* Number of users of pInitMutex */
3037   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
3038   void (*xLog)(void*,int,const char*); /* Function for logging */
3039   void *pLogArg;                       /* First argument to xLog() */
3040 #ifdef SQLITE_ENABLE_SQLLOG
3041   void(*xSqllog)(void*,sqlite3*,const char*, int);
3042   void *pSqllogArg;
3043 #endif
3044 #ifdef SQLITE_VDBE_COVERAGE
3045   /* The following callback (if not NULL) is invoked on every VDBE branch
3046   ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
3047   */
3048   void (*xVdbeBranch)(void*,int iSrcLine,u8 eThis,u8 eMx);  /* Callback */
3049   void *pVdbeBranchArg;                                     /* 1st argument */
3050 #endif
3051 #ifndef SQLITE_OMIT_BUILTIN_TEST
3052   int (*xTestCallback)(int);        /* Invoked by sqlite3FaultSim() */
3053 #endif
3054   int bLocaltimeFault;              /* True to fail localtime() calls */
3055 };
3056 
3057 /*
3058 ** This macro is used inside of assert() statements to indicate that
3059 ** the assert is only valid on a well-formed database.  Instead of:
3060 **
3061 **     assert( X );
3062 **
3063 ** One writes:
3064 **
3065 **     assert( X || CORRUPT_DB );
3066 **
3067 ** CORRUPT_DB is true during normal operation.  CORRUPT_DB does not indicate
3068 ** that the database is definitely corrupt, only that it might be corrupt.
3069 ** For most test cases, CORRUPT_DB is set to false using a special
3070 ** sqlite3_test_control().  This enables assert() statements to prove
3071 ** things that are always true for well-formed databases.
3072 */
3073 #define CORRUPT_DB  (sqlite3Config.neverCorrupt==0)
3074 
3075 /*
3076 ** Context pointer passed down through the tree-walk.
3077 */
3078 struct Walker {
3079   Parse *pParse;                            /* Parser context.  */
3080   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
3081   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
3082   void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
3083   int walkerDepth;                          /* Number of subqueries */
3084   u8 eCode;                                 /* A small processing code */
3085   union {                                   /* Extra data for callback */
3086     NameContext *pNC;                          /* Naming context */
3087     int n;                                     /* A counter */
3088     int iCur;                                  /* A cursor number */
3089     SrcList *pSrcList;                         /* FROM clause */
3090     struct SrcCount *pSrcCount;                /* Counting column references */
3091     struct CCurHint *pCCurHint;                /* Used by codeCursorHint() */
3092   } u;
3093 };
3094 
3095 /* Forward declarations */
3096 int sqlite3WalkExpr(Walker*, Expr*);
3097 int sqlite3WalkExprList(Walker*, ExprList*);
3098 int sqlite3WalkSelect(Walker*, Select*);
3099 int sqlite3WalkSelectExpr(Walker*, Select*);
3100 int sqlite3WalkSelectFrom(Walker*, Select*);
3101 int sqlite3ExprWalkNoop(Walker*, Expr*);
3102 
3103 /*
3104 ** Return code from the parse-tree walking primitives and their
3105 ** callbacks.
3106 */
3107 #define WRC_Continue    0   /* Continue down into children */
3108 #define WRC_Prune       1   /* Omit children but continue walking siblings */
3109 #define WRC_Abort       2   /* Abandon the tree walk */
3110 
3111 /*
3112 ** An instance of this structure represents a set of one or more CTEs
3113 ** (common table expressions) created by a single WITH clause.
3114 */
3115 struct With {
3116   int nCte;                       /* Number of CTEs in the WITH clause */
3117   With *pOuter;                   /* Containing WITH clause, or NULL */
3118   struct Cte {                    /* For each CTE in the WITH clause.... */
3119     char *zName;                    /* Name of this CTE */
3120     ExprList *pCols;                /* List of explicit column names, or NULL */
3121     Select *pSelect;                /* The definition of this CTE */
3122     const char *zCteErr;            /* Error message for circular references */
3123   } a[1];
3124 };
3125 
3126 #ifdef SQLITE_DEBUG
3127 /*
3128 ** An instance of the TreeView object is used for printing the content of
3129 ** data structures on sqlite3DebugPrintf() using a tree-like view.
3130 */
3131 struct TreeView {
3132   int iLevel;             /* Which level of the tree we are on */
3133   u8  bLine[100];         /* Draw vertical in column i if bLine[i] is true */
3134 };
3135 #endif /* SQLITE_DEBUG */
3136 
3137 /*
3138 ** Assuming zIn points to the first byte of a UTF-8 character,
3139 ** advance zIn to point to the first byte of the next UTF-8 character.
3140 */
3141 #define SQLITE_SKIP_UTF8(zIn) {                        \
3142   if( (*(zIn++))>=0xc0 ){                              \
3143     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
3144   }                                                    \
3145 }
3146 
3147 /*
3148 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
3149 ** the same name but without the _BKPT suffix.  These macros invoke
3150 ** routines that report the line-number on which the error originated
3151 ** using sqlite3_log().  The routines also provide a convenient place
3152 ** to set a debugger breakpoint.
3153 */
3154 int sqlite3CorruptError(int);
3155 int sqlite3MisuseError(int);
3156 int sqlite3CantopenError(int);
3157 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
3158 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
3159 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
3160 
3161 
3162 /*
3163 ** FTS4 is really an extension for FTS3.  It is enabled using the
3164 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also call
3165 ** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
3166 */
3167 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
3168 # define SQLITE_ENABLE_FTS3 1
3169 #endif
3170 
3171 /*
3172 ** The ctype.h header is needed for non-ASCII systems.  It is also
3173 ** needed by FTS3 when FTS3 is included in the amalgamation.
3174 */
3175 #if !defined(SQLITE_ASCII) || \
3176     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
3177 # include <ctype.h>
3178 #endif
3179 
3180 /*
3181 ** The following macros mimic the standard library functions toupper(),
3182 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
3183 ** sqlite versions only work for ASCII characters, regardless of locale.
3184 */
3185 #ifdef SQLITE_ASCII
3186 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
3187 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
3188 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
3189 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
3190 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
3191 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
3192 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
3193 #else
3194 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
3195 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
3196 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
3197 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
3198 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
3199 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
3200 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
3201 #endif
3202 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
3203 int sqlite3IsIdChar(u8);
3204 #endif
3205 
3206 /*
3207 ** Internal function prototypes
3208 */
3209 #define sqlite3StrICmp sqlite3_stricmp
3210 int sqlite3Strlen30(const char*);
3211 #define sqlite3StrNICmp sqlite3_strnicmp
3212 
3213 int sqlite3MallocInit(void);
3214 void sqlite3MallocEnd(void);
3215 void *sqlite3Malloc(u64);
3216 void *sqlite3MallocZero(u64);
3217 void *sqlite3DbMallocZero(sqlite3*, u64);
3218 void *sqlite3DbMallocRaw(sqlite3*, u64);
3219 char *sqlite3DbStrDup(sqlite3*,const char*);
3220 char *sqlite3DbStrNDup(sqlite3*,const char*, u64);
3221 void *sqlite3Realloc(void*, u64);
3222 void *sqlite3DbReallocOrFree(sqlite3 *, void *, u64);
3223 void *sqlite3DbRealloc(sqlite3 *, void *, u64);
3224 void sqlite3DbFree(sqlite3*, void*);
3225 int sqlite3MallocSize(void*);
3226 int sqlite3DbMallocSize(sqlite3*, void*);
3227 void *sqlite3ScratchMalloc(int);
3228 void sqlite3ScratchFree(void*);
3229 void *sqlite3PageMalloc(int);
3230 void sqlite3PageFree(void*);
3231 void sqlite3MemSetDefault(void);
3232 #ifndef SQLITE_OMIT_BUILTIN_TEST
3233 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
3234 #endif
3235 int sqlite3HeapNearlyFull(void);
3236 
3237 /*
3238 ** On systems with ample stack space and that support alloca(), make
3239 ** use of alloca() to obtain space for large automatic objects.  By default,
3240 ** obtain space from malloc().
3241 **
3242 ** The alloca() routine never returns NULL.  This will cause code paths
3243 ** that deal with sqlite3StackAlloc() failures to be unreachable.
3244 */
3245 #ifdef SQLITE_USE_ALLOCA
3246 # define sqlite3StackAllocRaw(D,N)   alloca(N)
3247 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
3248 # define sqlite3StackFree(D,P)
3249 #else
3250 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
3251 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
3252 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
3253 #endif
3254 
3255 #ifdef SQLITE_ENABLE_MEMSYS3
3256 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
3257 #endif
3258 #ifdef SQLITE_ENABLE_MEMSYS5
3259 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
3260 #endif
3261 
3262 
3263 #ifndef SQLITE_MUTEX_OMIT
3264   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
3265   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
3266   sqlite3_mutex *sqlite3MutexAlloc(int);
3267   int sqlite3MutexInit(void);
3268   int sqlite3MutexEnd(void);
3269 #endif
3270 #if !defined(SQLITE_MUTEX_OMIT) && !defined(SQLITE_MUTEX_NOOP)
3271   void sqlite3MemoryBarrier(void);
3272 #else
3273 # define sqlite3MemoryBarrier()
3274 #endif
3275 
3276 sqlite3_int64 sqlite3StatusValue(int);
3277 void sqlite3StatusUp(int, int);
3278 void sqlite3StatusDown(int, int);
3279 void sqlite3StatusHighwater(int, int);
3280 
3281 /* Access to mutexes used by sqlite3_status() */
3282 sqlite3_mutex *sqlite3Pcache1Mutex(void);
3283 sqlite3_mutex *sqlite3MallocMutex(void);
3284 
3285 #ifndef SQLITE_OMIT_FLOATING_POINT
3286   int sqlite3IsNaN(double);
3287 #else
3288 # define sqlite3IsNaN(X)  0
3289 #endif
3290 
3291 /*
3292 ** An instance of the following structure holds information about SQL
3293 ** functions arguments that are the parameters to the printf() function.
3294 */
3295 struct PrintfArguments {
3296   int nArg;                /* Total number of arguments */
3297   int nUsed;               /* Number of arguments used so far */
3298   sqlite3_value **apArg;   /* The argument values */
3299 };
3300 
3301 #define SQLITE_PRINTF_INTERNAL 0x01
3302 #define SQLITE_PRINTF_SQLFUNC  0x02
3303 void sqlite3VXPrintf(StrAccum*, u32, const char*, va_list);
3304 void sqlite3XPrintf(StrAccum*, u32, const char*, ...);
3305 char *sqlite3MPrintf(sqlite3*,const char*, ...);
3306 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
3307 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
3308   void sqlite3DebugPrintf(const char*, ...);
3309 #endif
3310 #if defined(SQLITE_TEST)
3311   void *sqlite3TestTextToPtr(const char*);
3312 #endif
3313 
3314 #if defined(SQLITE_DEBUG)
3315   void sqlite3TreeViewExpr(TreeView*, const Expr*, u8);
3316   void sqlite3TreeViewExprList(TreeView*, const ExprList*, u8, const char*);
3317   void sqlite3TreeViewSelect(TreeView*, const Select*, u8);
3318   void sqlite3TreeViewWith(TreeView*, const With*, u8);
3319 #endif
3320 
3321 
3322 void sqlite3SetString(char **, sqlite3*, const char*);
3323 void sqlite3ErrorMsg(Parse*, const char*, ...);
3324 int sqlite3Dequote(char*);
3325 void sqlite3TokenInit(Token*,char*);
3326 int sqlite3KeywordCode(const unsigned char*, int);
3327 int sqlite3RunParser(Parse*, const char*, char **);
3328 void sqlite3FinishCoding(Parse*);
3329 int sqlite3GetTempReg(Parse*);
3330 void sqlite3ReleaseTempReg(Parse*,int);
3331 int sqlite3GetTempRange(Parse*,int);
3332 void sqlite3ReleaseTempRange(Parse*,int,int);
3333 void sqlite3ClearTempRegCache(Parse*);
3334 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
3335 Expr *sqlite3Expr(sqlite3*,int,const char*);
3336 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
3337 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
3338 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
3339 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
3340 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
3341 void sqlite3ExprDelete(sqlite3*, Expr*);
3342 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
3343 void sqlite3ExprListSetSortOrder(ExprList*,int);
3344 void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
3345 void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
3346 void sqlite3ExprListDelete(sqlite3*, ExprList*);
3347 u32 sqlite3ExprListFlags(const ExprList*);
3348 int sqlite3Init(sqlite3*, char**);
3349 int sqlite3InitCallback(void*, int, char**, char**);
3350 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
3351 void sqlite3ResetAllSchemasOfConnection(sqlite3*);
3352 void sqlite3ResetOneSchema(sqlite3*,int);
3353 void sqlite3CollapseDatabaseArray(sqlite3*);
3354 void sqlite3CommitInternalChanges(sqlite3*);
3355 void sqlite3DeleteColumnNames(sqlite3*,Table*);
3356 int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
3357 Table *sqlite3ResultSetOfSelect(Parse*,Select*);
3358 void sqlite3OpenMasterTable(Parse *, int);
3359 Index *sqlite3PrimaryKeyIndex(Table*);
3360 i16 sqlite3ColumnOfIndex(Index*, i16);
3361 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
3362 #if SQLITE_ENABLE_HIDDEN_COLUMNS
3363   void sqlite3ColumnPropertiesFromName(Table*, Column*);
3364 #else
3365 # define sqlite3ColumnPropertiesFromName(T,C) /* no-op */
3366 #endif
3367 void sqlite3AddColumn(Parse*,Token*);
3368 void sqlite3AddNotNull(Parse*, int);
3369 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
3370 void sqlite3AddCheckConstraint(Parse*, Expr*);
3371 void sqlite3AddColumnType(Parse*,Token*);
3372 void sqlite3AddDefaultValue(Parse*,ExprSpan*);
3373 void sqlite3AddCollateType(Parse*, Token*);
3374 void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
3375 int sqlite3ParseUri(const char*,const char*,unsigned int*,
3376                     sqlite3_vfs**,char**,char **);
3377 Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
3378 int sqlite3CodeOnce(Parse *);
3379 
3380 #ifdef SQLITE_OMIT_BUILTIN_TEST
3381 # define sqlite3FaultSim(X) SQLITE_OK
3382 #else
3383   int sqlite3FaultSim(int);
3384 #endif
3385 
3386 Bitvec *sqlite3BitvecCreate(u32);
3387 int sqlite3BitvecTest(Bitvec*, u32);
3388 int sqlite3BitvecTestNotNull(Bitvec*, u32);
3389 int sqlite3BitvecSet(Bitvec*, u32);
3390 void sqlite3BitvecClear(Bitvec*, u32, void*);
3391 void sqlite3BitvecDestroy(Bitvec*);
3392 u32 sqlite3BitvecSize(Bitvec*);
3393 #ifndef SQLITE_OMIT_BUILTIN_TEST
3394 int sqlite3BitvecBuiltinTest(int,int*);
3395 #endif
3396 
3397 RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
3398 void sqlite3RowSetClear(RowSet*);
3399 void sqlite3RowSetInsert(RowSet*, i64);
3400 int sqlite3RowSetTest(RowSet*, int iBatch, i64);
3401 int sqlite3RowSetNext(RowSet*, i64*);
3402 
3403 void sqlite3CreateView(Parse*,Token*,Token*,Token*,ExprList*,Select*,int,int);
3404 
3405 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
3406   int sqlite3ViewGetColumnNames(Parse*,Table*);
3407 #else
3408 # define sqlite3ViewGetColumnNames(A,B) 0
3409 #endif
3410 
3411 #if SQLITE_MAX_ATTACHED>30
3412   int sqlite3DbMaskAllZero(yDbMask);
3413 #endif
3414 void sqlite3DropTable(Parse*, SrcList*, int, int);
3415 void sqlite3CodeDropTable(Parse*, Table*, int, int);
3416 void sqlite3DeleteTable(sqlite3*, Table*);
3417 #ifndef SQLITE_OMIT_AUTOINCREMENT
3418   void sqlite3AutoincrementBegin(Parse *pParse);
3419   void sqlite3AutoincrementEnd(Parse *pParse);
3420 #else
3421 # define sqlite3AutoincrementBegin(X)
3422 # define sqlite3AutoincrementEnd(X)
3423 #endif
3424 void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int);
3425 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
3426 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
3427 int sqlite3IdListIndex(IdList*,const char*);
3428 SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
3429 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
3430 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
3431                                       Token*, Select*, Expr*, IdList*);
3432 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
3433 void sqlite3SrcListFuncArgs(Parse*, SrcList*, ExprList*);
3434 int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
3435 void sqlite3SrcListShiftJoinType(SrcList*);
3436 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
3437 void sqlite3IdListDelete(sqlite3*, IdList*);
3438 void sqlite3SrcListDelete(sqlite3*, SrcList*);
3439 Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
3440 Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
3441                           Expr*, int, int);
3442 void sqlite3DropIndex(Parse*, SrcList*, int);
3443 int sqlite3Select(Parse*, Select*, SelectDest*);
3444 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
3445                          Expr*,ExprList*,u16,Expr*,Expr*);
3446 void sqlite3SelectDelete(sqlite3*, Select*);
3447 Table *sqlite3SrcListLookup(Parse*, SrcList*);
3448 int sqlite3IsReadOnly(Parse*, Table*, int);
3449 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
3450 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
3451 Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,Expr*,char*);
3452 #endif
3453 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
3454 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
3455 WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
3456 void sqlite3WhereEnd(WhereInfo*);
3457 u64 sqlite3WhereOutputRowCount(WhereInfo*);
3458 int sqlite3WhereIsDistinct(WhereInfo*);
3459 int sqlite3WhereIsOrdered(WhereInfo*);
3460 int sqlite3WhereIsSorted(WhereInfo*);
3461 int sqlite3WhereContinueLabel(WhereInfo*);
3462 int sqlite3WhereBreakLabel(WhereInfo*);
3463 int sqlite3WhereOkOnePass(WhereInfo*, int*);
3464 #define ONEPASS_OFF      0        /* Use of ONEPASS not allowed */
3465 #define ONEPASS_SINGLE   1        /* ONEPASS valid for a single row update */
3466 #define ONEPASS_MULTI    2        /* ONEPASS is valid for multiple rows */
3467 void sqlite3ExprCodeLoadIndexColumn(Parse*, Index*, int, int, int);
3468 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
3469 void sqlite3ExprCodeGetColumnToReg(Parse*, Table*, int, int, int);
3470 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
3471 void sqlite3ExprCodeMove(Parse*, int, int, int);
3472 void sqlite3ExprCacheStore(Parse*, int, int, int);
3473 void sqlite3ExprCachePush(Parse*);
3474 void sqlite3ExprCachePop(Parse*);
3475 void sqlite3ExprCacheRemove(Parse*, int, int);
3476 void sqlite3ExprCacheClear(Parse*);
3477 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
3478 void sqlite3ExprCode(Parse*, Expr*, int);
3479 void sqlite3ExprCodeCopy(Parse*, Expr*, int);
3480 void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
3481 void sqlite3ExprCodeAtInit(Parse*, Expr*, int, u8);
3482 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
3483 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
3484 void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
3485 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int, u8);
3486 #define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
3487 #define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
3488 #define SQLITE_ECEL_REF      0x04  /* Use ExprList.u.x.iOrderByCol */
3489 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
3490 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
3491 void sqlite3ExprIfFalseDup(Parse*, Expr*, int, int);
3492 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
3493 Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
3494 Table *sqlite3LocateTableItem(Parse*,int isView,struct SrcList_item *);
3495 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
3496 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
3497 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
3498 void sqlite3Vacuum(Parse*);
3499 int sqlite3RunVacuum(char**, sqlite3*);
3500 char *sqlite3NameFromToken(sqlite3*, Token*);
3501 int sqlite3ExprCompare(Expr*, Expr*, int);
3502 int sqlite3ExprListCompare(ExprList*, ExprList*, int);
3503 int sqlite3ExprImpliesExpr(Expr*, Expr*, int);
3504 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
3505 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
3506 int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
3507 Vdbe *sqlite3GetVdbe(Parse*);
3508 #ifndef SQLITE_OMIT_BUILTIN_TEST
3509 void sqlite3PrngSaveState(void);
3510 void sqlite3PrngRestoreState(void);
3511 #endif
3512 void sqlite3RollbackAll(sqlite3*,int);
3513 void sqlite3CodeVerifySchema(Parse*, int);
3514 void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
3515 void sqlite3BeginTransaction(Parse*, int);
3516 void sqlite3CommitTransaction(Parse*);
3517 void sqlite3RollbackTransaction(Parse*);
3518 void sqlite3Savepoint(Parse*, int, Token*);
3519 void sqlite3CloseSavepoints(sqlite3 *);
3520 void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
3521 int sqlite3ExprIsConstant(Expr*);
3522 int sqlite3ExprIsConstantNotJoin(Expr*);
3523 int sqlite3ExprIsConstantOrFunction(Expr*, u8);
3524 int sqlite3ExprIsTableConstant(Expr*,int);
3525 #ifdef SQLITE_ENABLE_CURSOR_HINTS
3526 int sqlite3ExprContainsSubquery(Expr*);
3527 #endif
3528 int sqlite3ExprIsInteger(Expr*, int*);
3529 int sqlite3ExprCanBeNull(const Expr*);
3530 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
3531 int sqlite3IsRowid(const char*);
3532 void sqlite3GenerateRowDelete(
3533     Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8,int);
3534 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*, int);
3535 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
3536 void sqlite3ResolvePartIdxLabel(Parse*,int);
3537 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
3538                                      u8,u8,int,int*);
3539 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
3540 int sqlite3OpenTableAndIndices(Parse*, Table*, int, u8, int, u8*, int*, int*);
3541 void sqlite3BeginWriteOperation(Parse*, int, int);
3542 void sqlite3MultiWrite(Parse*);
3543 void sqlite3MayAbort(Parse*);
3544 void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
3545 void sqlite3UniqueConstraint(Parse*, int, Index*);
3546 void sqlite3RowidConstraint(Parse*, int, Table*);
3547 Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
3548 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
3549 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
3550 IdList *sqlite3IdListDup(sqlite3*,IdList*);
3551 Select *sqlite3SelectDup(sqlite3*,Select*,int);
3552 #if SELECTTRACE_ENABLED
3553 void sqlite3SelectSetName(Select*,const char*);
3554 #else
3555 # define sqlite3SelectSetName(A,B)
3556 #endif
3557 void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
3558 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
3559 void sqlite3RegisterBuiltinFunctions(sqlite3*);
3560 void sqlite3RegisterDateTimeFunctions(void);
3561 void sqlite3RegisterGlobalFunctions(void);
3562 int sqlite3SafetyCheckOk(sqlite3*);
3563 int sqlite3SafetyCheckSickOrOk(sqlite3*);
3564 void sqlite3ChangeCookie(Parse*, int);
3565 
3566 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
3567 void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
3568 #endif
3569 
3570 #ifndef SQLITE_OMIT_TRIGGER
3571   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
3572                            Expr*,int, int);
3573   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
3574   void sqlite3DropTrigger(Parse*, SrcList*, int);
3575   void sqlite3DropTriggerPtr(Parse*, Trigger*);
3576   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
3577   Trigger *sqlite3TriggerList(Parse *, Table *);
3578   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
3579                             int, int, int);
3580   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
3581   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
3582   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
3583   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
3584   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
3585                                         Select*,u8);
3586   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
3587   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
3588   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
3589   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
3590   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
3591 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
3592 # define sqlite3IsToplevel(p) ((p)->pToplevel==0)
3593 #else
3594 # define sqlite3TriggersExist(B,C,D,E,F) 0
3595 # define sqlite3DeleteTrigger(A,B)
3596 # define sqlite3DropTriggerPtr(A,B)
3597 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
3598 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
3599 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
3600 # define sqlite3TriggerList(X, Y) 0
3601 # define sqlite3ParseToplevel(p) p
3602 # define sqlite3IsToplevel(p) 1
3603 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
3604 #endif
3605 
3606 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
3607 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
3608 void sqlite3DeferForeignKey(Parse*, int);
3609 #ifndef SQLITE_OMIT_AUTHORIZATION
3610   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
3611   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
3612   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
3613   void sqlite3AuthContextPop(AuthContext*);
3614   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
3615 #else
3616 # define sqlite3AuthRead(a,b,c,d)
3617 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
3618 # define sqlite3AuthContextPush(a,b,c)
3619 # define sqlite3AuthContextPop(a)  ((void)(a))
3620 #endif
3621 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
3622 void sqlite3Detach(Parse*, Expr*);
3623 void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
3624 int sqlite3FixSrcList(DbFixer*, SrcList*);
3625 int sqlite3FixSelect(DbFixer*, Select*);
3626 int sqlite3FixExpr(DbFixer*, Expr*);
3627 int sqlite3FixExprList(DbFixer*, ExprList*);
3628 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
3629 int sqlite3AtoF(const char *z, double*, int, u8);
3630 int sqlite3GetInt32(const char *, int*);
3631 int sqlite3Atoi(const char*);
3632 int sqlite3Utf16ByteLen(const void *pData, int nChar);
3633 int sqlite3Utf8CharLen(const char *pData, int nByte);
3634 u32 sqlite3Utf8Read(const u8**);
3635 LogEst sqlite3LogEst(u64);
3636 LogEst sqlite3LogEstAdd(LogEst,LogEst);
3637 #ifndef SQLITE_OMIT_VIRTUALTABLE
3638 LogEst sqlite3LogEstFromDouble(double);
3639 #endif
3640 u64 sqlite3LogEstToInt(LogEst);
3641 
3642 /*
3643 ** Routines to read and write variable-length integers.  These used to
3644 ** be defined locally, but now we use the varint routines in the util.c
3645 ** file.
3646 */
3647 int sqlite3PutVarint(unsigned char*, u64);
3648 u8 sqlite3GetVarint(const unsigned char *, u64 *);
3649 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
3650 int sqlite3VarintLen(u64 v);
3651 
3652 /*
3653 ** The common case is for a varint to be a single byte.  They following
3654 ** macros handle the common case without a procedure call, but then call
3655 ** the procedure for larger varints.
3656 */
3657 #define getVarint32(A,B)  \
3658   (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
3659 #define putVarint32(A,B)  \
3660   (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
3661   sqlite3PutVarint((A),(B)))
3662 #define getVarint    sqlite3GetVarint
3663 #define putVarint    sqlite3PutVarint
3664 
3665 
3666 const char *sqlite3IndexAffinityStr(sqlite3*, Index*);
3667 void sqlite3TableAffinity(Vdbe*, Table*, int);
3668 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
3669 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
3670 char sqlite3ExprAffinity(Expr *pExpr);
3671 int sqlite3Atoi64(const char*, i64*, int, u8);
3672 int sqlite3DecOrHexToI64(const char*, i64*);
3673 void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
3674 void sqlite3Error(sqlite3*,int);
3675 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
3676 u8 sqlite3HexToInt(int h);
3677 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
3678 
3679 #if defined(SQLITE_NEED_ERR_NAME)
3680 const char *sqlite3ErrName(int);
3681 #endif
3682 
3683 const char *sqlite3ErrStr(int);
3684 int sqlite3ReadSchema(Parse *pParse);
3685 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
3686 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
3687 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
3688 Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*, int);
3689 Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
3690 Expr *sqlite3ExprSkipCollate(Expr*);
3691 int sqlite3CheckCollSeq(Parse *, CollSeq *);
3692 int sqlite3CheckObjectName(Parse *, const char *);
3693 void sqlite3VdbeSetChanges(sqlite3 *, int);
3694 int sqlite3AddInt64(i64*,i64);
3695 int sqlite3SubInt64(i64*,i64);
3696 int sqlite3MulInt64(i64*,i64);
3697 int sqlite3AbsInt32(int);
3698 #ifdef SQLITE_ENABLE_8_3_NAMES
3699 void sqlite3FileSuffix3(const char*, char*);
3700 #else
3701 # define sqlite3FileSuffix3(X,Y)
3702 #endif
3703 u8 sqlite3GetBoolean(const char *z,u8);
3704 
3705 const void *sqlite3ValueText(sqlite3_value*, u8);
3706 int sqlite3ValueBytes(sqlite3_value*, u8);
3707 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
3708                         void(*)(void*));
3709 void sqlite3ValueSetNull(sqlite3_value*);
3710 void sqlite3ValueFree(sqlite3_value*);
3711 sqlite3_value *sqlite3ValueNew(sqlite3 *);
3712 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
3713 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
3714 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
3715 #ifndef SQLITE_AMALGAMATION
3716 extern const unsigned char sqlite3OpcodeProperty[];
3717 extern const char sqlite3StrBINARY[];
3718 extern const unsigned char sqlite3UpperToLower[];
3719 extern const unsigned char sqlite3CtypeMap[];
3720 extern const Token sqlite3IntTokens[];
3721 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
3722 extern SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
3723 #ifndef SQLITE_OMIT_WSD
3724 extern int sqlite3PendingByte;
3725 #endif
3726 #endif
3727 void sqlite3RootPageMoved(sqlite3*, int, int, int);
3728 void sqlite3Reindex(Parse*, Token*, Token*);
3729 void sqlite3AlterFunctions(void);
3730 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
3731 int sqlite3GetToken(const unsigned char *, int *);
3732 void sqlite3NestedParse(Parse*, const char*, ...);
3733 void sqlite3ExpirePreparedStatements(sqlite3*);
3734 int sqlite3CodeSubselect(Parse *, Expr *, int, int);
3735 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
3736 void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
3737 int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
3738 int sqlite3ResolveExprNames(NameContext*, Expr*);
3739 int sqlite3ResolveExprListNames(NameContext*, ExprList*);
3740 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
3741 void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
3742 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
3743 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
3744 void sqlite3AlterFinishAddColumn(Parse *, Token *);
3745 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
3746 CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
3747 char sqlite3AffinityType(const char*, u8*);
3748 void sqlite3Analyze(Parse*, Token*, Token*);
3749 int sqlite3InvokeBusyHandler(BusyHandler*);
3750 int sqlite3FindDb(sqlite3*, Token*);
3751 int sqlite3FindDbName(sqlite3 *, const char *);
3752 int sqlite3AnalysisLoad(sqlite3*,int iDB);
3753 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
3754 void sqlite3DefaultRowEst(Index*);
3755 void sqlite3RegisterLikeFunctions(sqlite3*, int);
3756 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
3757 void sqlite3MinimumFileFormat(Parse*, int, int);
3758 void sqlite3SchemaClear(void *);
3759 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
3760 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
3761 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
3762 void sqlite3KeyInfoUnref(KeyInfo*);
3763 KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
3764 KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
3765 #ifdef SQLITE_DEBUG
3766 int sqlite3KeyInfoIsWriteable(KeyInfo*);
3767 #endif
3768 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
3769   void (*)(sqlite3_context*,int,sqlite3_value **),
3770   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
3771   FuncDestructor *pDestructor
3772 );
3773 int sqlite3ApiExit(sqlite3 *db, int);
3774 int sqlite3OpenTempDatabase(Parse *);
3775 
3776 void sqlite3StrAccumInit(StrAccum*, sqlite3*, char*, int, int);
3777 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
3778 void sqlite3StrAccumAppendAll(StrAccum*,const char*);
3779 void sqlite3AppendChar(StrAccum*,int,char);
3780 char *sqlite3StrAccumFinish(StrAccum*);
3781 void sqlite3StrAccumReset(StrAccum*);
3782 void sqlite3SelectDestInit(SelectDest*,int,int);
3783 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
3784 
3785 void sqlite3BackupRestart(sqlite3_backup *);
3786 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
3787 
3788 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
3789 void sqlite3AnalyzeFunctions(void);
3790 int sqlite3Stat4ProbeSetValue(Parse*,Index*,UnpackedRecord**,Expr*,u8,int,int*);
3791 int sqlite3Stat4ValueFromExpr(Parse*, Expr*, u8, sqlite3_value**);
3792 void sqlite3Stat4ProbeFree(UnpackedRecord*);
3793 int sqlite3Stat4Column(sqlite3*, const void*, int, int, sqlite3_value**);
3794 #endif
3795 
3796 /*
3797 ** The interface to the LEMON-generated parser
3798 */
3799 void *sqlite3ParserAlloc(void*(*)(u64));
3800 void sqlite3ParserFree(void*, void(*)(void*));
3801 void sqlite3Parser(void*, int, Token, Parse*);
3802 #ifdef YYTRACKMAXSTACKDEPTH
3803   int sqlite3ParserStackPeak(void*);
3804 #endif
3805 
3806 void sqlite3AutoLoadExtensions(sqlite3*);
3807 #ifndef SQLITE_OMIT_LOAD_EXTENSION
3808   void sqlite3CloseExtensions(sqlite3*);
3809 #else
3810 # define sqlite3CloseExtensions(X)
3811 #endif
3812 
3813 #ifndef SQLITE_OMIT_SHARED_CACHE
3814   void sqlite3TableLock(Parse *, int, int, u8, const char *);
3815 #else
3816   #define sqlite3TableLock(v,w,x,y,z)
3817 #endif
3818 
3819 #ifdef SQLITE_TEST
3820   int sqlite3Utf8To8(unsigned char*);
3821 #endif
3822 
3823 #ifdef SQLITE_OMIT_VIRTUALTABLE
3824 #  define sqlite3VtabClear(Y)
3825 #  define sqlite3VtabSync(X,Y) SQLITE_OK
3826 #  define sqlite3VtabRollback(X)
3827 #  define sqlite3VtabCommit(X)
3828 #  define sqlite3VtabInSync(db) 0
3829 #  define sqlite3VtabLock(X)
3830 #  define sqlite3VtabUnlock(X)
3831 #  define sqlite3VtabUnlockList(X)
3832 #  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
3833 #  define sqlite3GetVTable(X,Y)  ((VTable*)0)
3834 #else
3835    void sqlite3VtabClear(sqlite3 *db, Table*);
3836    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
3837    int sqlite3VtabSync(sqlite3 *db, Vdbe*);
3838    int sqlite3VtabRollback(sqlite3 *db);
3839    int sqlite3VtabCommit(sqlite3 *db);
3840    void sqlite3VtabLock(VTable *);
3841    void sqlite3VtabUnlock(VTable *);
3842    void sqlite3VtabUnlockList(sqlite3*);
3843    int sqlite3VtabSavepoint(sqlite3 *, int, int);
3844    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
3845    VTable *sqlite3GetVTable(sqlite3*, Table*);
3846 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
3847 #endif
3848 int sqlite3VtabEponymousTableInit(Parse*,Module*);
3849 void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
3850 void sqlite3VtabMakeWritable(Parse*,Table*);
3851 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
3852 void sqlite3VtabFinishParse(Parse*, Token*);
3853 void sqlite3VtabArgInit(Parse*);
3854 void sqlite3VtabArgExtend(Parse*, Token*);
3855 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
3856 int sqlite3VtabCallConnect(Parse*, Table*);
3857 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
3858 int sqlite3VtabBegin(sqlite3 *, VTable *);
3859 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
3860 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
3861 sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
3862 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
3863 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
3864 void sqlite3ParserReset(Parse*);
3865 int sqlite3Reprepare(Vdbe*);
3866 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
3867 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
3868 int sqlite3TempInMemory(const sqlite3*);
3869 const char *sqlite3JournalModename(int);
3870 #ifndef SQLITE_OMIT_WAL
3871   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
3872   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
3873 #endif
3874 #ifndef SQLITE_OMIT_CTE
3875   With *sqlite3WithAdd(Parse*,With*,Token*,ExprList*,Select*);
3876   void sqlite3WithDelete(sqlite3*,With*);
3877   void sqlite3WithPush(Parse*, With*, u8);
3878 #else
3879 #define sqlite3WithPush(x,y,z)
3880 #define sqlite3WithDelete(x,y)
3881 #endif
3882 
3883 /* Declarations for functions in fkey.c. All of these are replaced by
3884 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
3885 ** key functionality is available. If OMIT_TRIGGER is defined but
3886 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
3887 ** this case foreign keys are parsed, but no other functionality is
3888 ** provided (enforcement of FK constraints requires the triggers sub-system).
3889 */
3890 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
3891   void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
3892   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
3893   void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
3894   int sqlite3FkRequired(Parse*, Table*, int*, int);
3895   u32 sqlite3FkOldmask(Parse*, Table*);
3896   FKey *sqlite3FkReferences(Table *);
3897 #else
3898   #define sqlite3FkActions(a,b,c,d,e,f)
3899   #define sqlite3FkCheck(a,b,c,d,e,f)
3900   #define sqlite3FkDropTable(a,b,c)
3901   #define sqlite3FkOldmask(a,b)         0
3902   #define sqlite3FkRequired(a,b,c,d)    0
3903 #endif
3904 #ifndef SQLITE_OMIT_FOREIGN_KEY
3905   void sqlite3FkDelete(sqlite3 *, Table*);
3906   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
3907 #else
3908   #define sqlite3FkDelete(a,b)
3909   #define sqlite3FkLocateIndex(a,b,c,d,e)
3910 #endif
3911 
3912 
3913 /*
3914 ** Available fault injectors.  Should be numbered beginning with 0.
3915 */
3916 #define SQLITE_FAULTINJECTOR_MALLOC     0
3917 #define SQLITE_FAULTINJECTOR_COUNT      1
3918 
3919 /*
3920 ** The interface to the code in fault.c used for identifying "benign"
3921 ** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
3922 ** is not defined.
3923 */
3924 #ifndef SQLITE_OMIT_BUILTIN_TEST
3925   void sqlite3BeginBenignMalloc(void);
3926   void sqlite3EndBenignMalloc(void);
3927 #else
3928   #define sqlite3BeginBenignMalloc()
3929   #define sqlite3EndBenignMalloc()
3930 #endif
3931 
3932 /*
3933 ** Allowed return values from sqlite3FindInIndex()
3934 */
3935 #define IN_INDEX_ROWID        1   /* Search the rowid of the table */
3936 #define IN_INDEX_EPH          2   /* Search an ephemeral b-tree */
3937 #define IN_INDEX_INDEX_ASC    3   /* Existing index ASCENDING */
3938 #define IN_INDEX_INDEX_DESC   4   /* Existing index DESCENDING */
3939 #define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
3940 /*
3941 ** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
3942 */
3943 #define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
3944 #define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
3945 #define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
3946 int sqlite3FindInIndex(Parse *, Expr *, u32, int*);
3947 
3948 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
3949   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
3950   int sqlite3JournalSize(sqlite3_vfs *);
3951   int sqlite3JournalCreate(sqlite3_file *);
3952   int sqlite3JournalExists(sqlite3_file *p);
3953 #else
3954   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
3955   #define sqlite3JournalExists(p) 1
3956 #endif
3957 
3958 void sqlite3MemJournalOpen(sqlite3_file *);
3959 int sqlite3MemJournalSize(void);
3960 int sqlite3IsMemJournal(sqlite3_file *);
3961 
3962 void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p);
3963 #if SQLITE_MAX_EXPR_DEPTH>0
3964   int sqlite3SelectExprHeight(Select *);
3965   int sqlite3ExprCheckHeight(Parse*, int);
3966 #else
3967   #define sqlite3SelectExprHeight(x) 0
3968   #define sqlite3ExprCheckHeight(x,y)
3969 #endif
3970 
3971 u32 sqlite3Get4byte(const u8*);
3972 void sqlite3Put4byte(u8*, u32);
3973 
3974 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
3975   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
3976   void sqlite3ConnectionUnlocked(sqlite3 *db);
3977   void sqlite3ConnectionClosed(sqlite3 *db);
3978 #else
3979   #define sqlite3ConnectionBlocked(x,y)
3980   #define sqlite3ConnectionUnlocked(x)
3981   #define sqlite3ConnectionClosed(x)
3982 #endif
3983 
3984 #ifdef SQLITE_DEBUG
3985   void sqlite3ParserTrace(FILE*, char *);
3986 #endif
3987 
3988 /*
3989 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
3990 ** sqlite3IoTrace is a pointer to a printf-like routine used to
3991 ** print I/O tracing messages.
3992 */
3993 #ifdef SQLITE_ENABLE_IOTRACE
3994 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
3995   void sqlite3VdbeIOTraceSql(Vdbe*);
3996 SQLITE_API SQLITE_EXTERN void (SQLITE_CDECL *sqlite3IoTrace)(const char*,...);
3997 #else
3998 # define IOTRACE(A)
3999 # define sqlite3VdbeIOTraceSql(X)
4000 #endif
4001 
4002 /*
4003 ** These routines are available for the mem2.c debugging memory allocator
4004 ** only.  They are used to verify that different "types" of memory
4005 ** allocations are properly tracked by the system.
4006 **
4007 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
4008 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
4009 ** a single bit set.
4010 **
4011 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
4012 ** argument match the type set by the previous sqlite3MemdebugSetType().
4013 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
4014 **
4015 ** sqlite3MemdebugNoType() returns true if none of the bits in its second
4016 ** argument match the type set by the previous sqlite3MemdebugSetType().
4017 **
4018 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
4019 ** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
4020 ** it might have been allocated by lookaside, except the allocation was
4021 ** too large or lookaside was already full.  It is important to verify
4022 ** that allocations that might have been satisfied by lookaside are not
4023 ** passed back to non-lookaside free() routines.  Asserts such as the
4024 ** example above are placed on the non-lookaside free() routines to verify
4025 ** this constraint.
4026 **
4027 ** All of this is no-op for a production build.  It only comes into
4028 ** play when the SQLITE_MEMDEBUG compile-time option is used.
4029 */
4030 #ifdef SQLITE_MEMDEBUG
4031   void sqlite3MemdebugSetType(void*,u8);
4032   int sqlite3MemdebugHasType(void*,u8);
4033   int sqlite3MemdebugNoType(void*,u8);
4034 #else
4035 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
4036 # define sqlite3MemdebugHasType(X,Y)  1
4037 # define sqlite3MemdebugNoType(X,Y)   1
4038 #endif
4039 #define MEMTYPE_HEAP       0x01  /* General heap allocations */
4040 #define MEMTYPE_LOOKASIDE  0x02  /* Heap that might have been lookaside */
4041 #define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
4042 #define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
4043 
4044 /*
4045 ** Threading interface
4046 */
4047 #if SQLITE_MAX_WORKER_THREADS>0
4048 int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
4049 int sqlite3ThreadJoin(SQLiteThread*, void**);
4050 #endif
4051 
4052 #if defined(SQLITE_ENABLE_DBSTAT_VTAB) || defined(SQLITE_TEST)
4053 int sqlite3DbstatRegister(sqlite3*);
4054 #endif
4055 
4056 #endif /* _SQLITEINT_H_ */
4057