xref: /sqlite-3.40.0/src/sqliteInt.h (revision 9a243e69)
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 /* Special Comments:
19 **
20 ** Some comments have special meaning to the tools that measure test
21 ** coverage:
22 **
23 **    NO_TEST                     - The branches on this line are not
24 **                                  measured by branch coverage.  This is
25 **                                  used on lines of code that actually
26 **                                  implement parts of coverage testing.
27 **
28 **    OPTIMIZATION-IF-TRUE        - This branch is allowed to alway be false
29 **                                  and the correct answer is still obtained,
30 **                                  though perhaps more slowly.
31 **
32 **    OPTIMIZATION-IF-FALSE       - This branch is allowed to alway be true
33 **                                  and the correct answer is still obtained,
34 **                                  though perhaps more slowly.
35 **
36 **    PREVENTS-HARMLESS-OVERREAD  - This branch prevents a buffer overread
37 **                                  that would be harmless and undetectable
38 **                                  if it did occur.
39 **
40 ** In all cases, the special comment must be enclosed in the usual
41 ** slash-asterisk...asterisk-slash comment marks, with no spaces between the
42 ** asterisks and the comment text.
43 */
44 
45 /*
46 ** Make sure the Tcl calling convention macro is defined.  This macro is
47 ** only used by test code and Tcl integration code.
48 */
49 #ifndef SQLITE_TCLAPI
50 #  define SQLITE_TCLAPI
51 #endif
52 
53 /*
54 ** Include the header file used to customize the compiler options for MSVC.
55 ** This should be done first so that it can successfully prevent spurious
56 ** compiler warnings due to subsequent content in this file and other files
57 ** that are included by this file.
58 */
59 #include "msvc.h"
60 
61 /*
62 ** Special setup for VxWorks
63 */
64 #include "vxworks.h"
65 
66 /*
67 ** These #defines should enable >2GB file support on POSIX if the
68 ** underlying operating system supports it.  If the OS lacks
69 ** large file support, or if the OS is windows, these should be no-ops.
70 **
71 ** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
72 ** system #includes.  Hence, this block of code must be the very first
73 ** code in all source files.
74 **
75 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
76 ** on the compiler command line.  This is necessary if you are compiling
77 ** on a recent machine (ex: Red Hat 7.2) but you want your code to work
78 ** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
79 ** without this option, LFS is enable.  But LFS does not exist in the kernel
80 ** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
81 ** portability you should omit LFS.
82 **
83 ** The previous paragraph was written in 2005.  (This paragraph is written
84 ** on 2008-11-28.) These days, all Linux kernels support large files, so
85 ** you should probably leave LFS enabled.  But some embedded platforms might
86 ** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
87 **
88 ** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
89 */
90 #ifndef SQLITE_DISABLE_LFS
91 # define _LARGE_FILE       1
92 # ifndef _FILE_OFFSET_BITS
93 #   define _FILE_OFFSET_BITS 64
94 # endif
95 # define _LARGEFILE_SOURCE 1
96 #endif
97 
98 /* The GCC_VERSION and MSVC_VERSION macros are used to
99 ** conditionally include optimizations for each of these compilers.  A
100 ** value of 0 means that compiler is not being used.  The
101 ** SQLITE_DISABLE_INTRINSIC macro means do not use any compiler-specific
102 ** optimizations, and hence set all compiler macros to 0
103 **
104 ** There was once also a CLANG_VERSION macro.  However, we learn that the
105 ** version numbers in clang are for "marketing" only and are inconsistent
106 ** and unreliable.  Fortunately, all versions of clang also recognize the
107 ** gcc version numbers and have reasonable settings for gcc version numbers,
108 ** so the GCC_VERSION macro will be set to a correct non-zero value even
109 ** when compiling with clang.
110 */
111 #if defined(__GNUC__) && !defined(SQLITE_DISABLE_INTRINSIC)
112 # define GCC_VERSION (__GNUC__*1000000+__GNUC_MINOR__*1000+__GNUC_PATCHLEVEL__)
113 #else
114 # define GCC_VERSION 0
115 #endif
116 #if defined(_MSC_VER) && !defined(SQLITE_DISABLE_INTRINSIC)
117 # define MSVC_VERSION _MSC_VER
118 #else
119 # define MSVC_VERSION 0
120 #endif
121 
122 /* Needed for various definitions... */
123 #if defined(__GNUC__) && !defined(_GNU_SOURCE)
124 # define _GNU_SOURCE
125 #endif
126 
127 #if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
128 # define _BSD_SOURCE
129 #endif
130 
131 /*
132 ** For MinGW, check to see if we can include the header file containing its
133 ** version information, among other things.  Normally, this internal MinGW
134 ** header file would [only] be included automatically by other MinGW header
135 ** files; however, the contained version information is now required by this
136 ** header file to work around binary compatibility issues (see below) and
137 ** this is the only known way to reliably obtain it.  This entire #if block
138 ** would be completely unnecessary if there was any other way of detecting
139 ** MinGW via their preprocessor (e.g. if they customized their GCC to define
140 ** some MinGW-specific macros).  When compiling for MinGW, either the
141 ** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
142 ** defined; otherwise, detection of conditions specific to MinGW will be
143 ** disabled.
144 */
145 #if defined(_HAVE_MINGW_H)
146 # include "mingw.h"
147 #elif defined(_HAVE__MINGW_H)
148 # include "_mingw.h"
149 #endif
150 
151 /*
152 ** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
153 ** define is required to maintain binary compatibility with the MSVC runtime
154 ** library in use (e.g. for Windows XP).
155 */
156 #if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
157     defined(_WIN32) && !defined(_WIN64) && \
158     defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
159     defined(__MSVCRT__)
160 # define _USE_32BIT_TIME_T
161 #endif
162 
163 /* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
164 ** first in QNX.  Also, the _USE_32BIT_TIME_T macro must appear first for
165 ** MinGW.
166 */
167 #include "sqlite3.h"
168 
169 /*
170 ** Include the configuration header output by 'configure' if we're using the
171 ** autoconf-based build
172 */
173 #if defined(_HAVE_SQLITE_CONFIG_H) && !defined(SQLITECONFIG_H)
174 #include "config.h"
175 #define SQLITECONFIG_H 1
176 #endif
177 
178 #include "sqliteLimit.h"
179 
180 /* Disable nuisance warnings on Borland compilers */
181 #if defined(__BORLANDC__)
182 #pragma warn -rch /* unreachable code */
183 #pragma warn -ccc /* Condition is always true or false */
184 #pragma warn -aus /* Assigned value is never used */
185 #pragma warn -csu /* Comparing signed and unsigned */
186 #pragma warn -spa /* Suspicious pointer arithmetic */
187 #endif
188 
189 /*
190 ** Include standard header files as necessary
191 */
192 #ifdef HAVE_STDINT_H
193 #include <stdint.h>
194 #endif
195 #ifdef HAVE_INTTYPES_H
196 #include <inttypes.h>
197 #endif
198 
199 /*
200 ** The following macros are used to cast pointers to integers and
201 ** integers to pointers.  The way you do this varies from one compiler
202 ** to the next, so we have developed the following set of #if statements
203 ** to generate appropriate macros for a wide range of compilers.
204 **
205 ** The correct "ANSI" way to do this is to use the intptr_t type.
206 ** Unfortunately, that typedef is not available on all compilers, or
207 ** if it is available, it requires an #include of specific headers
208 ** that vary from one machine to the next.
209 **
210 ** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
211 ** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
212 ** So we have to define the macros in different ways depending on the
213 ** compiler.
214 */
215 #if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
216 # define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
217 # define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
218 #elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
219 # define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
220 # define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
221 #elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
222 # define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
223 # define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
224 #else                          /* Generates a warning - but it always works */
225 # define SQLITE_INT_TO_PTR(X)  ((void*)(X))
226 # define SQLITE_PTR_TO_INT(X)  ((int)(X))
227 #endif
228 
229 /*
230 ** A macro to hint to the compiler that a function should not be
231 ** inlined.
232 */
233 #if defined(__GNUC__)
234 #  define SQLITE_NOINLINE  __attribute__((noinline))
235 #elif defined(_MSC_VER) && _MSC_VER>=1310
236 #  define SQLITE_NOINLINE  __declspec(noinline)
237 #else
238 #  define SQLITE_NOINLINE
239 #endif
240 
241 /*
242 ** Make sure that the compiler intrinsics we desire are enabled when
243 ** compiling with an appropriate version of MSVC unless prevented by
244 ** the SQLITE_DISABLE_INTRINSIC define.
245 */
246 #if !defined(SQLITE_DISABLE_INTRINSIC)
247 #  if defined(_MSC_VER) && _MSC_VER>=1400
248 #    if !defined(_WIN32_WCE)
249 #      include <intrin.h>
250 #      pragma intrinsic(_byteswap_ushort)
251 #      pragma intrinsic(_byteswap_ulong)
252 #      pragma intrinsic(_byteswap_uint64)
253 #      pragma intrinsic(_ReadWriteBarrier)
254 #    else
255 #      include <cmnintrin.h>
256 #    endif
257 #  endif
258 #endif
259 
260 /*
261 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
262 ** 0 means mutexes are permanently disable and the library is never
263 ** threadsafe.  1 means the library is serialized which is the highest
264 ** level of threadsafety.  2 means the library is multithreaded - multiple
265 ** threads can use SQLite as long as no two threads try to use the same
266 ** database connection at the same time.
267 **
268 ** Older versions of SQLite used an optional THREADSAFE macro.
269 ** We support that for legacy.
270 **
271 ** To ensure that the correct value of "THREADSAFE" is reported when querying
272 ** for compile-time options at runtime (e.g. "PRAGMA compile_options"), this
273 ** logic is partially replicated in ctime.c. If it is updated here, it should
274 ** also be updated there.
275 */
276 #if !defined(SQLITE_THREADSAFE)
277 # if defined(THREADSAFE)
278 #   define SQLITE_THREADSAFE THREADSAFE
279 # else
280 #   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
281 # endif
282 #endif
283 
284 /*
285 ** Powersafe overwrite is on by default.  But can be turned off using
286 ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
287 */
288 #ifndef SQLITE_POWERSAFE_OVERWRITE
289 # define SQLITE_POWERSAFE_OVERWRITE 1
290 #endif
291 
292 /*
293 ** EVIDENCE-OF: R-25715-37072 Memory allocation statistics are enabled by
294 ** default unless SQLite is compiled with SQLITE_DEFAULT_MEMSTATUS=0 in
295 ** which case memory allocation statistics are disabled by default.
296 */
297 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
298 # define SQLITE_DEFAULT_MEMSTATUS 1
299 #endif
300 
301 /*
302 ** Exactly one of the following macros must be defined in order to
303 ** specify which memory allocation subsystem to use.
304 **
305 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
306 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
307 **     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
308 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
309 **
310 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
311 ** assert() macro is enabled, each call into the Win32 native heap subsystem
312 ** will cause HeapValidate to be called.  If heap validation should fail, an
313 ** assertion will be triggered.
314 **
315 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
316 ** the default.
317 */
318 #if defined(SQLITE_SYSTEM_MALLOC) \
319   + defined(SQLITE_WIN32_MALLOC) \
320   + defined(SQLITE_ZERO_MALLOC) \
321   + defined(SQLITE_MEMDEBUG)>1
322 # error "Two or more of the following compile-time configuration options\
323  are defined but at most one is allowed:\
324  SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
325  SQLITE_ZERO_MALLOC"
326 #endif
327 #if defined(SQLITE_SYSTEM_MALLOC) \
328   + defined(SQLITE_WIN32_MALLOC) \
329   + defined(SQLITE_ZERO_MALLOC) \
330   + defined(SQLITE_MEMDEBUG)==0
331 # define SQLITE_SYSTEM_MALLOC 1
332 #endif
333 
334 /*
335 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
336 ** sizes of memory allocations below this value where possible.
337 */
338 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
339 # define SQLITE_MALLOC_SOFT_LIMIT 1024
340 #endif
341 
342 /*
343 ** We need to define _XOPEN_SOURCE as follows in order to enable
344 ** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
345 ** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
346 ** it.
347 */
348 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
349 #  define _XOPEN_SOURCE 600
350 #endif
351 
352 /*
353 ** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
354 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
355 ** make it true by defining or undefining NDEBUG.
356 **
357 ** Setting NDEBUG makes the code smaller and faster by disabling the
358 ** assert() statements in the code.  So we want the default action
359 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
360 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
361 ** feature.
362 */
363 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
364 # define NDEBUG 1
365 #endif
366 #if defined(NDEBUG) && defined(SQLITE_DEBUG)
367 # undef NDEBUG
368 #endif
369 
370 /*
371 ** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
372 */
373 #if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
374 # define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
375 #endif
376 
377 /*
378 ** The testcase() macro is used to aid in coverage testing.  When
379 ** doing coverage testing, the condition inside the argument to
380 ** testcase() must be evaluated both true and false in order to
381 ** get full branch coverage.  The testcase() macro is inserted
382 ** to help ensure adequate test coverage in places where simple
383 ** condition/decision coverage is inadequate.  For example, testcase()
384 ** can be used to make sure boundary values are tested.  For
385 ** bitmask tests, testcase() can be used to make sure each bit
386 ** is significant and used at least once.  On switch statements
387 ** where multiple cases go to the same block of code, testcase()
388 ** can insure that all cases are evaluated.
389 **
390 */
391 #ifdef SQLITE_COVERAGE_TEST
392   void sqlite3Coverage(int);
393 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
394 #else
395 # define testcase(X)
396 #endif
397 
398 /*
399 ** The TESTONLY macro is used to enclose variable declarations or
400 ** other bits of code that are needed to support the arguments
401 ** within testcase() and assert() macros.
402 */
403 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
404 # define TESTONLY(X)  X
405 #else
406 # define TESTONLY(X)
407 #endif
408 
409 /*
410 ** Sometimes we need a small amount of code such as a variable initialization
411 ** to setup for a later assert() statement.  We do not want this code to
412 ** appear when assert() is disabled.  The following macro is therefore
413 ** used to contain that setup code.  The "VVA" acronym stands for
414 ** "Verification, Validation, and Accreditation".  In other words, the
415 ** code within VVA_ONLY() will only run during verification processes.
416 */
417 #ifndef NDEBUG
418 # define VVA_ONLY(X)  X
419 #else
420 # define VVA_ONLY(X)
421 #endif
422 
423 /*
424 ** The ALWAYS and NEVER macros surround boolean expressions which
425 ** are intended to always be true or false, respectively.  Such
426 ** expressions could be omitted from the code completely.  But they
427 ** are included in a few cases in order to enhance the resilience
428 ** of SQLite to unexpected behavior - to make the code "self-healing"
429 ** or "ductile" rather than being "brittle" and crashing at the first
430 ** hint of unplanned behavior.
431 **
432 ** In other words, ALWAYS and NEVER are added for defensive code.
433 **
434 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
435 ** be true and false so that the unreachable code they specify will
436 ** not be counted as untested code.
437 */
438 #if defined(SQLITE_COVERAGE_TEST) || defined(SQLITE_MUTATION_TEST)
439 # define ALWAYS(X)      (1)
440 # define NEVER(X)       (0)
441 #elif !defined(NDEBUG)
442 # define ALWAYS(X)      ((X)?1:(assert(0),0))
443 # define NEVER(X)       ((X)?(assert(0),1):0)
444 #else
445 # define ALWAYS(X)      (X)
446 # define NEVER(X)       (X)
447 #endif
448 
449 /*
450 ** Some malloc failures are only possible if SQLITE_TEST_REALLOC_STRESS is
451 ** defined.  We need to defend against those failures when testing with
452 ** SQLITE_TEST_REALLOC_STRESS, but we don't want the unreachable branches
453 ** during a normal build.  The following macro can be used to disable tests
454 ** that are always false except when SQLITE_TEST_REALLOC_STRESS is set.
455 */
456 #if defined(SQLITE_TEST_REALLOC_STRESS)
457 # define ONLY_IF_REALLOC_STRESS(X)  (X)
458 #elif !defined(NDEBUG)
459 # define ONLY_IF_REALLOC_STRESS(X)  ((X)?(assert(0),1):0)
460 #else
461 # define ONLY_IF_REALLOC_STRESS(X)  (0)
462 #endif
463 
464 /*
465 ** Declarations used for tracing the operating system interfaces.
466 */
467 #if defined(SQLITE_FORCE_OS_TRACE) || defined(SQLITE_TEST) || \
468     (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
469   extern int sqlite3OSTrace;
470 # define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
471 # define SQLITE_HAVE_OS_TRACE
472 #else
473 # define OSTRACE(X)
474 # undef  SQLITE_HAVE_OS_TRACE
475 #endif
476 
477 /*
478 ** Is the sqlite3ErrName() function needed in the build?  Currently,
479 ** it is needed by "mutex_w32.c" (when debugging), "os_win.c" (when
480 ** OSTRACE is enabled), and by several "test*.c" files (which are
481 ** compiled using SQLITE_TEST).
482 */
483 #if defined(SQLITE_HAVE_OS_TRACE) || defined(SQLITE_TEST) || \
484     (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
485 # define SQLITE_NEED_ERR_NAME
486 #else
487 # undef  SQLITE_NEED_ERR_NAME
488 #endif
489 
490 /*
491 ** SQLITE_ENABLE_EXPLAIN_COMMENTS is incompatible with SQLITE_OMIT_EXPLAIN
492 */
493 #ifdef SQLITE_OMIT_EXPLAIN
494 # undef SQLITE_ENABLE_EXPLAIN_COMMENTS
495 #endif
496 
497 /*
498 ** Return true (non-zero) if the input is an integer that is too large
499 ** to fit in 32-bits.  This macro is used inside of various testcase()
500 ** macros to verify that we have tested SQLite for large-file support.
501 */
502 #define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
503 
504 /*
505 ** The macro unlikely() is a hint that surrounds a boolean
506 ** expression that is usually false.  Macro likely() surrounds
507 ** a boolean expression that is usually true.  These hints could,
508 ** in theory, be used by the compiler to generate better code, but
509 ** currently they are just comments for human readers.
510 */
511 #define likely(X)    (X)
512 #define unlikely(X)  (X)
513 
514 #include "hash.h"
515 #include "parse.h"
516 #include <stdio.h>
517 #include <stdlib.h>
518 #include <string.h>
519 #include <assert.h>
520 #include <stddef.h>
521 
522 /*
523 ** Use a macro to replace memcpy() if compiled with SQLITE_INLINE_MEMCPY.
524 ** This allows better measurements of where memcpy() is used when running
525 ** cachegrind.  But this macro version of memcpy() is very slow so it
526 ** should not be used in production.  This is a performance measurement
527 ** hack only.
528 */
529 #ifdef SQLITE_INLINE_MEMCPY
530 # define memcpy(D,S,N) {char*xxd=(char*)(D);const char*xxs=(const char*)(S);\
531                         int xxn=(N);while(xxn-->0)*(xxd++)=*(xxs++);}
532 #endif
533 
534 /*
535 ** If compiling for a processor that lacks floating point support,
536 ** substitute integer for floating-point
537 */
538 #ifdef SQLITE_OMIT_FLOATING_POINT
539 # define double sqlite_int64
540 # define float sqlite_int64
541 # define LONGDOUBLE_TYPE sqlite_int64
542 # ifndef SQLITE_BIG_DBL
543 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
544 # endif
545 # define SQLITE_OMIT_DATETIME_FUNCS 1
546 # define SQLITE_OMIT_TRACE 1
547 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
548 # undef SQLITE_HAVE_ISNAN
549 #endif
550 #ifndef SQLITE_BIG_DBL
551 # define SQLITE_BIG_DBL (1e99)
552 #endif
553 
554 /*
555 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
556 ** afterward. Having this macro allows us to cause the C compiler
557 ** to omit code used by TEMP tables without messy #ifndef statements.
558 */
559 #ifdef SQLITE_OMIT_TEMPDB
560 #define OMIT_TEMPDB 1
561 #else
562 #define OMIT_TEMPDB 0
563 #endif
564 
565 /*
566 ** The "file format" number is an integer that is incremented whenever
567 ** the VDBE-level file format changes.  The following macros define the
568 ** the default file format for new databases and the maximum file format
569 ** that the library can read.
570 */
571 #define SQLITE_MAX_FILE_FORMAT 4
572 #ifndef SQLITE_DEFAULT_FILE_FORMAT
573 # define SQLITE_DEFAULT_FILE_FORMAT 4
574 #endif
575 
576 /*
577 ** Determine whether triggers are recursive by default.  This can be
578 ** changed at run-time using a pragma.
579 */
580 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
581 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
582 #endif
583 
584 /*
585 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
586 ** on the command-line
587 */
588 #ifndef SQLITE_TEMP_STORE
589 # define SQLITE_TEMP_STORE 1
590 #endif
591 
592 /*
593 ** If no value has been provided for SQLITE_MAX_WORKER_THREADS, or if
594 ** SQLITE_TEMP_STORE is set to 3 (never use temporary files), set it
595 ** to zero.
596 */
597 #if SQLITE_TEMP_STORE==3 || SQLITE_THREADSAFE==0
598 # undef SQLITE_MAX_WORKER_THREADS
599 # define SQLITE_MAX_WORKER_THREADS 0
600 #endif
601 #ifndef SQLITE_MAX_WORKER_THREADS
602 # define SQLITE_MAX_WORKER_THREADS 8
603 #endif
604 #ifndef SQLITE_DEFAULT_WORKER_THREADS
605 # define SQLITE_DEFAULT_WORKER_THREADS 0
606 #endif
607 #if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
608 # undef SQLITE_MAX_WORKER_THREADS
609 # define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
610 #endif
611 
612 /*
613 ** The default initial allocation for the pagecache when using separate
614 ** pagecaches for each database connection.  A positive number is the
615 ** number of pages.  A negative number N translations means that a buffer
616 ** of -1024*N bytes is allocated and used for as many pages as it will hold.
617 **
618 ** The default value of "20" was choosen to minimize the run-time of the
619 ** speedtest1 test program with options: --shrink-memory --reprepare
620 */
621 #ifndef SQLITE_DEFAULT_PCACHE_INITSZ
622 # define SQLITE_DEFAULT_PCACHE_INITSZ 20
623 #endif
624 
625 /*
626 ** The compile-time options SQLITE_MMAP_READWRITE and
627 ** SQLITE_ENABLE_BATCH_ATOMIC_WRITE are not compatible with one another.
628 ** You must choose one or the other (or neither) but not both.
629 */
630 #if defined(SQLITE_MMAP_READWRITE) && defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
631 #error Cannot use both SQLITE_MMAP_READWRITE and SQLITE_ENABLE_BATCH_ATOMIC_WRITE
632 #endif
633 
634 /*
635 ** GCC does not define the offsetof() macro so we'll have to do it
636 ** ourselves.
637 */
638 #ifndef offsetof
639 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
640 #endif
641 
642 /*
643 ** Macros to compute minimum and maximum of two numbers.
644 */
645 #ifndef MIN
646 # define MIN(A,B) ((A)<(B)?(A):(B))
647 #endif
648 #ifndef MAX
649 # define MAX(A,B) ((A)>(B)?(A):(B))
650 #endif
651 
652 /*
653 ** Swap two objects of type TYPE.
654 */
655 #define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
656 
657 /*
658 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
659 ** not, there are still machines out there that use EBCDIC.)
660 */
661 #if 'A' == '\301'
662 # define SQLITE_EBCDIC 1
663 #else
664 # define SQLITE_ASCII 1
665 #endif
666 
667 /*
668 ** Integers of known sizes.  These typedefs might change for architectures
669 ** where the sizes very.  Preprocessor macros are available so that the
670 ** types can be conveniently redefined at compile-type.  Like this:
671 **
672 **         cc '-DUINTPTR_TYPE=long long int' ...
673 */
674 #ifndef UINT32_TYPE
675 # ifdef HAVE_UINT32_T
676 #  define UINT32_TYPE uint32_t
677 # else
678 #  define UINT32_TYPE unsigned int
679 # endif
680 #endif
681 #ifndef UINT16_TYPE
682 # ifdef HAVE_UINT16_T
683 #  define UINT16_TYPE uint16_t
684 # else
685 #  define UINT16_TYPE unsigned short int
686 # endif
687 #endif
688 #ifndef INT16_TYPE
689 # ifdef HAVE_INT16_T
690 #  define INT16_TYPE int16_t
691 # else
692 #  define INT16_TYPE short int
693 # endif
694 #endif
695 #ifndef UINT8_TYPE
696 # ifdef HAVE_UINT8_T
697 #  define UINT8_TYPE uint8_t
698 # else
699 #  define UINT8_TYPE unsigned char
700 # endif
701 #endif
702 #ifndef INT8_TYPE
703 # ifdef HAVE_INT8_T
704 #  define INT8_TYPE int8_t
705 # else
706 #  define INT8_TYPE signed char
707 # endif
708 #endif
709 #ifndef LONGDOUBLE_TYPE
710 # define LONGDOUBLE_TYPE long double
711 #endif
712 typedef sqlite_int64 i64;          /* 8-byte signed integer */
713 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
714 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
715 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
716 typedef INT16_TYPE i16;            /* 2-byte signed integer */
717 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
718 typedef INT8_TYPE i8;              /* 1-byte signed integer */
719 
720 /*
721 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
722 ** that can be stored in a u32 without loss of data.  The value
723 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
724 ** have to specify the value in the less intuitive manner shown:
725 */
726 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
727 
728 /*
729 ** The datatype used to store estimates of the number of rows in a
730 ** table or index.  This is an unsigned integer type.  For 99.9% of
731 ** the world, a 32-bit integer is sufficient.  But a 64-bit integer
732 ** can be used at compile-time if desired.
733 */
734 #ifdef SQLITE_64BIT_STATS
735  typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
736 #else
737  typedef u32 tRowcnt;    /* 32-bit is the default */
738 #endif
739 
740 /*
741 ** Estimated quantities used for query planning are stored as 16-bit
742 ** logarithms.  For quantity X, the value stored is 10*log2(X).  This
743 ** gives a possible range of values of approximately 1.0e986 to 1e-986.
744 ** But the allowed values are "grainy".  Not every value is representable.
745 ** For example, quantities 16 and 17 are both represented by a LogEst
746 ** of 40.  However, since LogEst quantities are suppose to be estimates,
747 ** not exact values, this imprecision is not a problem.
748 **
749 ** "LogEst" is short for "Logarithmic Estimate".
750 **
751 ** Examples:
752 **      1 -> 0              20 -> 43          10000 -> 132
753 **      2 -> 10             25 -> 46          25000 -> 146
754 **      3 -> 16            100 -> 66        1000000 -> 199
755 **      4 -> 20           1000 -> 99        1048576 -> 200
756 **     10 -> 33           1024 -> 100    4294967296 -> 320
757 **
758 ** The LogEst can be negative to indicate fractional values.
759 ** Examples:
760 **
761 **    0.5 -> -10           0.1 -> -33        0.0625 -> -40
762 */
763 typedef INT16_TYPE LogEst;
764 
765 /*
766 ** Set the SQLITE_PTRSIZE macro to the number of bytes in a pointer
767 */
768 #ifndef SQLITE_PTRSIZE
769 # if defined(__SIZEOF_POINTER__)
770 #   define SQLITE_PTRSIZE __SIZEOF_POINTER__
771 # elif defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
772        defined(_M_ARM)   || defined(__arm__)    || defined(__x86)
773 #   define SQLITE_PTRSIZE 4
774 # else
775 #   define SQLITE_PTRSIZE 8
776 # endif
777 #endif
778 
779 /* The uptr type is an unsigned integer large enough to hold a pointer
780 */
781 #if defined(HAVE_STDINT_H)
782   typedef uintptr_t uptr;
783 #elif SQLITE_PTRSIZE==4
784   typedef u32 uptr;
785 #else
786   typedef u64 uptr;
787 #endif
788 
789 /*
790 ** The SQLITE_WITHIN(P,S,E) macro checks to see if pointer P points to
791 ** something between S (inclusive) and E (exclusive).
792 **
793 ** In other words, S is a buffer and E is a pointer to the first byte after
794 ** the end of buffer S.  This macro returns true if P points to something
795 ** contained within the buffer S.
796 */
797 #define SQLITE_WITHIN(P,S,E) (((uptr)(P)>=(uptr)(S))&&((uptr)(P)<(uptr)(E)))
798 
799 
800 /*
801 ** Macros to determine whether the machine is big or little endian,
802 ** and whether or not that determination is run-time or compile-time.
803 **
804 ** For best performance, an attempt is made to guess at the byte-order
805 ** using C-preprocessor macros.  If that is unsuccessful, or if
806 ** -DSQLITE_BYTEORDER=0 is set, then byte-order is determined
807 ** at run-time.
808 */
809 #ifndef SQLITE_BYTEORDER
810 # if defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
811      defined(__x86_64) || defined(__x86_64__) || defined(_M_X64)  ||    \
812      defined(_M_AMD64) || defined(_M_ARM)     || defined(__x86)   ||    \
813      defined(__arm__)
814 #   define SQLITE_BYTEORDER    1234
815 # elif defined(sparc)    || defined(__ppc__)
816 #   define SQLITE_BYTEORDER    4321
817 # else
818 #   define SQLITE_BYTEORDER 0
819 # endif
820 #endif
821 #if SQLITE_BYTEORDER==4321
822 # define SQLITE_BIGENDIAN    1
823 # define SQLITE_LITTLEENDIAN 0
824 # define SQLITE_UTF16NATIVE  SQLITE_UTF16BE
825 #elif SQLITE_BYTEORDER==1234
826 # define SQLITE_BIGENDIAN    0
827 # define SQLITE_LITTLEENDIAN 1
828 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
829 #else
830 # ifdef SQLITE_AMALGAMATION
831   const int sqlite3one = 1;
832 # else
833   extern const int sqlite3one;
834 # endif
835 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
836 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
837 # define SQLITE_UTF16NATIVE  (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
838 #endif
839 
840 /*
841 ** Constants for the largest and smallest possible 64-bit signed integers.
842 ** These macros are designed to work correctly on both 32-bit and 64-bit
843 ** compilers.
844 */
845 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
846 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
847 
848 /*
849 ** Round up a number to the next larger multiple of 8.  This is used
850 ** to force 8-byte alignment on 64-bit architectures.
851 */
852 #define ROUND8(x)     (((x)+7)&~7)
853 
854 /*
855 ** Round down to the nearest multiple of 8
856 */
857 #define ROUNDDOWN8(x) ((x)&~7)
858 
859 /*
860 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
861 ** macro is used only within assert() to verify that the code gets
862 ** all alignment restrictions correct.
863 **
864 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
865 ** underlying malloc() implementation might return us 4-byte aligned
866 ** pointers.  In that case, only verify 4-byte alignment.
867 */
868 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
869 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
870 #else
871 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
872 #endif
873 
874 /*
875 ** Disable MMAP on platforms where it is known to not work
876 */
877 #if defined(__OpenBSD__) || defined(__QNXNTO__)
878 # undef SQLITE_MAX_MMAP_SIZE
879 # define SQLITE_MAX_MMAP_SIZE 0
880 #endif
881 
882 /*
883 ** Default maximum size of memory used by memory-mapped I/O in the VFS
884 */
885 #ifdef __APPLE__
886 # include <TargetConditionals.h>
887 #endif
888 #ifndef SQLITE_MAX_MMAP_SIZE
889 # if defined(__linux__) \
890   || defined(_WIN32) \
891   || (defined(__APPLE__) && defined(__MACH__)) \
892   || defined(__sun) \
893   || defined(__FreeBSD__) \
894   || defined(__DragonFly__)
895 #   define SQLITE_MAX_MMAP_SIZE 0x7fff0000  /* 2147418112 */
896 # else
897 #   define SQLITE_MAX_MMAP_SIZE 0
898 # endif
899 #endif
900 
901 /*
902 ** The default MMAP_SIZE is zero on all platforms.  Or, even if a larger
903 ** default MMAP_SIZE is specified at compile-time, make sure that it does
904 ** not exceed the maximum mmap size.
905 */
906 #ifndef SQLITE_DEFAULT_MMAP_SIZE
907 # define SQLITE_DEFAULT_MMAP_SIZE 0
908 #endif
909 #if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
910 # undef SQLITE_DEFAULT_MMAP_SIZE
911 # define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
912 #endif
913 
914 /*
915 ** Only one of SQLITE_ENABLE_STAT3 or SQLITE_ENABLE_STAT4 can be defined.
916 ** Priority is given to SQLITE_ENABLE_STAT4.  If either are defined, also
917 ** define SQLITE_ENABLE_STAT3_OR_STAT4
918 */
919 #ifdef SQLITE_ENABLE_STAT4
920 # undef SQLITE_ENABLE_STAT3
921 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
922 #elif SQLITE_ENABLE_STAT3
923 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
924 #elif SQLITE_ENABLE_STAT3_OR_STAT4
925 # undef SQLITE_ENABLE_STAT3_OR_STAT4
926 #endif
927 
928 /*
929 ** SELECTTRACE_ENABLED will be either 1 or 0 depending on whether or not
930 ** the Select query generator tracing logic is turned on.
931 */
932 #if defined(SQLITE_DEBUG) || defined(SQLITE_ENABLE_SELECTTRACE)
933 # define SELECTTRACE_ENABLED 1
934 #else
935 # define SELECTTRACE_ENABLED 0
936 #endif
937 
938 /*
939 ** An instance of the following structure is used to store the busy-handler
940 ** callback for a given sqlite handle.
941 **
942 ** The sqlite.busyHandler member of the sqlite struct contains the busy
943 ** callback for the database handle. Each pager opened via the sqlite
944 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
945 ** callback is currently invoked only from within pager.c.
946 */
947 typedef struct BusyHandler BusyHandler;
948 struct BusyHandler {
949   int (*xFunc)(void *,int);  /* The busy callback */
950   void *pArg;                /* First arg to busy callback */
951   int nBusy;                 /* Incremented with each busy call */
952 };
953 
954 /*
955 ** Name of the master database table.  The master database table
956 ** is a special table that holds the names and attributes of all
957 ** user tables and indices.
958 */
959 #define MASTER_NAME       "sqlite_master"
960 #define TEMP_MASTER_NAME  "sqlite_temp_master"
961 
962 /*
963 ** The root-page of the master database table.
964 */
965 #define MASTER_ROOT       1
966 
967 /*
968 ** The name of the schema table.
969 */
970 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
971 
972 /*
973 ** A convenience macro that returns the number of elements in
974 ** an array.
975 */
976 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
977 
978 /*
979 ** Determine if the argument is a power of two
980 */
981 #define IsPowerOfTwo(X) (((X)&((X)-1))==0)
982 
983 /*
984 ** The following value as a destructor means to use sqlite3DbFree().
985 ** The sqlite3DbFree() routine requires two parameters instead of the
986 ** one parameter that destructors normally want.  So we have to introduce
987 ** this magic value that the code knows to handle differently.  Any
988 ** pointer will work here as long as it is distinct from SQLITE_STATIC
989 ** and SQLITE_TRANSIENT.
990 */
991 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3MallocSize)
992 
993 /*
994 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
995 ** not support Writable Static Data (WSD) such as global and static variables.
996 ** All variables must either be on the stack or dynamically allocated from
997 ** the heap.  When WSD is unsupported, the variable declarations scattered
998 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
999 ** macro is used for this purpose.  And instead of referencing the variable
1000 ** directly, we use its constant as a key to lookup the run-time allocated
1001 ** buffer that holds real variable.  The constant is also the initializer
1002 ** for the run-time allocated buffer.
1003 **
1004 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
1005 ** macros become no-ops and have zero performance impact.
1006 */
1007 #ifdef SQLITE_OMIT_WSD
1008   #define SQLITE_WSD const
1009   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
1010   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
1011   int sqlite3_wsd_init(int N, int J);
1012   void *sqlite3_wsd_find(void *K, int L);
1013 #else
1014   #define SQLITE_WSD
1015   #define GLOBAL(t,v) v
1016   #define sqlite3GlobalConfig sqlite3Config
1017 #endif
1018 
1019 /*
1020 ** The following macros are used to suppress compiler warnings and to
1021 ** make it clear to human readers when a function parameter is deliberately
1022 ** left unused within the body of a function. This usually happens when
1023 ** a function is called via a function pointer. For example the
1024 ** implementation of an SQL aggregate step callback may not use the
1025 ** parameter indicating the number of arguments passed to the aggregate,
1026 ** if it knows that this is enforced elsewhere.
1027 **
1028 ** When a function parameter is not used at all within the body of a function,
1029 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
1030 ** However, these macros may also be used to suppress warnings related to
1031 ** parameters that may or may not be used depending on compilation options.
1032 ** For example those parameters only used in assert() statements. In these
1033 ** cases the parameters are named as per the usual conventions.
1034 */
1035 #define UNUSED_PARAMETER(x) (void)(x)
1036 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
1037 
1038 /*
1039 ** Forward references to structures
1040 */
1041 typedef struct AggInfo AggInfo;
1042 typedef struct AuthContext AuthContext;
1043 typedef struct AutoincInfo AutoincInfo;
1044 typedef struct Bitvec Bitvec;
1045 typedef struct CollSeq CollSeq;
1046 typedef struct Column Column;
1047 typedef struct Db Db;
1048 typedef struct Schema Schema;
1049 typedef struct Expr Expr;
1050 typedef struct ExprList ExprList;
1051 typedef struct ExprSpan ExprSpan;
1052 typedef struct FKey FKey;
1053 typedef struct FuncDestructor FuncDestructor;
1054 typedef struct FuncDef FuncDef;
1055 typedef struct FuncDefHash FuncDefHash;
1056 typedef struct IdList IdList;
1057 typedef struct Index Index;
1058 typedef struct IndexSample IndexSample;
1059 typedef struct KeyClass KeyClass;
1060 typedef struct KeyInfo KeyInfo;
1061 typedef struct Lookaside Lookaside;
1062 typedef struct LookasideSlot LookasideSlot;
1063 typedef struct Module Module;
1064 typedef struct NameContext NameContext;
1065 typedef struct Parse Parse;
1066 typedef struct PreUpdate PreUpdate;
1067 typedef struct PrintfArguments PrintfArguments;
1068 typedef struct RowSet RowSet;
1069 typedef struct Savepoint Savepoint;
1070 typedef struct Select Select;
1071 typedef struct SQLiteThread SQLiteThread;
1072 typedef struct SelectDest SelectDest;
1073 typedef struct SrcList SrcList;
1074 typedef struct StrAccum StrAccum;
1075 typedef struct Table Table;
1076 typedef struct TableLock TableLock;
1077 typedef struct Token Token;
1078 typedef struct TreeView TreeView;
1079 typedef struct Trigger Trigger;
1080 typedef struct TriggerPrg TriggerPrg;
1081 typedef struct TriggerStep TriggerStep;
1082 typedef struct UnpackedRecord UnpackedRecord;
1083 typedef struct VTable VTable;
1084 typedef struct VtabCtx VtabCtx;
1085 typedef struct Walker Walker;
1086 typedef struct WhereInfo WhereInfo;
1087 typedef struct With With;
1088 
1089 /* A VList object records a mapping between parameters/variables/wildcards
1090 ** in the SQL statement (such as $abc, @pqr, or :xyz) and the integer
1091 ** variable number associated with that parameter.  See the format description
1092 ** on the sqlite3VListAdd() routine for more information.  A VList is really
1093 ** just an array of integers.
1094 */
1095 typedef int VList;
1096 
1097 /*
1098 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
1099 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
1100 ** pointer types (i.e. FuncDef) defined above.
1101 */
1102 #include "btree.h"
1103 #include "vdbe.h"
1104 #include "pager.h"
1105 #include "pcache.h"
1106 #include "os.h"
1107 #include "mutex.h"
1108 
1109 /* The SQLITE_EXTRA_DURABLE compile-time option used to set the default
1110 ** synchronous setting to EXTRA.  It is no longer supported.
1111 */
1112 #ifdef SQLITE_EXTRA_DURABLE
1113 # warning Use SQLITE_DEFAULT_SYNCHRONOUS=3 instead of SQLITE_EXTRA_DURABLE
1114 # define SQLITE_DEFAULT_SYNCHRONOUS 3
1115 #endif
1116 
1117 /*
1118 ** Default synchronous levels.
1119 **
1120 ** Note that (for historcal reasons) the PAGER_SYNCHRONOUS_* macros differ
1121 ** from the SQLITE_DEFAULT_SYNCHRONOUS value by 1.
1122 **
1123 **           PAGER_SYNCHRONOUS       DEFAULT_SYNCHRONOUS
1124 **   OFF           1                         0
1125 **   NORMAL        2                         1
1126 **   FULL          3                         2
1127 **   EXTRA         4                         3
1128 **
1129 ** The "PRAGMA synchronous" statement also uses the zero-based numbers.
1130 ** In other words, the zero-based numbers are used for all external interfaces
1131 ** and the one-based values are used internally.
1132 */
1133 #ifndef SQLITE_DEFAULT_SYNCHRONOUS
1134 # define SQLITE_DEFAULT_SYNCHRONOUS 2
1135 #endif
1136 #ifndef SQLITE_DEFAULT_WAL_SYNCHRONOUS
1137 # define SQLITE_DEFAULT_WAL_SYNCHRONOUS SQLITE_DEFAULT_SYNCHRONOUS
1138 #endif
1139 
1140 /*
1141 ** Each database file to be accessed by the system is an instance
1142 ** of the following structure.  There are normally two of these structures
1143 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
1144 ** aDb[1] is the database file used to hold temporary tables.  Additional
1145 ** databases may be attached.
1146 */
1147 struct Db {
1148   char *zDbSName;      /* Name of this database. (schema name, not filename) */
1149   Btree *pBt;          /* The B*Tree structure for this database file */
1150   u8 safety_level;     /* How aggressive at syncing data to disk */
1151   u8 bSyncSet;         /* True if "PRAGMA synchronous=N" has been run */
1152   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
1153 };
1154 
1155 /*
1156 ** An instance of the following structure stores a database schema.
1157 **
1158 ** Most Schema objects are associated with a Btree.  The exception is
1159 ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
1160 ** In shared cache mode, a single Schema object can be shared by multiple
1161 ** Btrees that refer to the same underlying BtShared object.
1162 **
1163 ** Schema objects are automatically deallocated when the last Btree that
1164 ** references them is destroyed.   The TEMP Schema is manually freed by
1165 ** sqlite3_close().
1166 *
1167 ** A thread must be holding a mutex on the corresponding Btree in order
1168 ** to access Schema content.  This implies that the thread must also be
1169 ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
1170 ** For a TEMP Schema, only the connection mutex is required.
1171 */
1172 struct Schema {
1173   int schema_cookie;   /* Database schema version number for this file */
1174   int iGeneration;     /* Generation counter.  Incremented with each change */
1175   Hash tblHash;        /* All tables indexed by name */
1176   Hash idxHash;        /* All (named) indices indexed by name */
1177   Hash trigHash;       /* All triggers indexed by name */
1178   Hash fkeyHash;       /* All foreign keys by referenced table name */
1179   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
1180   u8 file_format;      /* Schema format version for this file */
1181   u8 enc;              /* Text encoding used by this database */
1182   u16 schemaFlags;     /* Flags associated with this schema */
1183   int cache_size;      /* Number of pages to use in the cache */
1184 };
1185 
1186 /*
1187 ** These macros can be used to test, set, or clear bits in the
1188 ** Db.pSchema->flags field.
1189 */
1190 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))
1191 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->schemaFlags&(P))!=0)
1192 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->schemaFlags|=(P)
1193 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->schemaFlags&=~(P)
1194 
1195 /*
1196 ** Allowed values for the DB.pSchema->flags field.
1197 **
1198 ** The DB_SchemaLoaded flag is set after the database schema has been
1199 ** read into internal hash tables.
1200 **
1201 ** DB_UnresetViews means that one or more views have column names that
1202 ** have been filled out.  If the schema changes, these column names might
1203 ** changes and so the view will need to be reset.
1204 */
1205 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
1206 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
1207 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
1208 #define DB_ResetWanted     0x0008  /* Reset the schema when nSchemaLock==0 */
1209 
1210 /*
1211 ** The number of different kinds of things that can be limited
1212 ** using the sqlite3_limit() interface.
1213 */
1214 #define SQLITE_N_LIMIT (SQLITE_LIMIT_WORKER_THREADS+1)
1215 
1216 /*
1217 ** Lookaside malloc is a set of fixed-size buffers that can be used
1218 ** to satisfy small transient memory allocation requests for objects
1219 ** associated with a particular database connection.  The use of
1220 ** lookaside malloc provides a significant performance enhancement
1221 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
1222 ** SQL statements.
1223 **
1224 ** The Lookaside structure holds configuration information about the
1225 ** lookaside malloc subsystem.  Each available memory allocation in
1226 ** the lookaside subsystem is stored on a linked list of LookasideSlot
1227 ** objects.
1228 **
1229 ** Lookaside allocations are only allowed for objects that are associated
1230 ** with a particular database connection.  Hence, schema information cannot
1231 ** be stored in lookaside because in shared cache mode the schema information
1232 ** is shared by multiple database connections.  Therefore, while parsing
1233 ** schema information, the Lookaside.bEnabled flag is cleared so that
1234 ** lookaside allocations are not used to construct the schema objects.
1235 */
1236 struct Lookaside {
1237   u32 bDisable;           /* Only operate the lookaside when zero */
1238   u16 sz;                 /* Size of each buffer in bytes */
1239   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
1240   u32 nSlot;              /* Number of lookaside slots allocated */
1241   u32 anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
1242   LookasideSlot *pInit;   /* List of buffers not previously used */
1243   LookasideSlot *pFree;   /* List of available buffers */
1244   void *pStart;           /* First byte of available memory space */
1245   void *pEnd;             /* First byte past end of available space */
1246 };
1247 struct LookasideSlot {
1248   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
1249 };
1250 
1251 /*
1252 ** A hash table for built-in function definitions.  (Application-defined
1253 ** functions use a regular table table from hash.h.)
1254 **
1255 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
1256 ** Collisions are on the FuncDef.u.pHash chain.
1257 */
1258 #define SQLITE_FUNC_HASH_SZ 23
1259 struct FuncDefHash {
1260   FuncDef *a[SQLITE_FUNC_HASH_SZ];       /* Hash table for functions */
1261 };
1262 
1263 #ifdef SQLITE_USER_AUTHENTICATION
1264 /*
1265 ** Information held in the "sqlite3" database connection object and used
1266 ** to manage user authentication.
1267 */
1268 typedef struct sqlite3_userauth sqlite3_userauth;
1269 struct sqlite3_userauth {
1270   u8 authLevel;                 /* Current authentication level */
1271   int nAuthPW;                  /* Size of the zAuthPW in bytes */
1272   char *zAuthPW;                /* Password used to authenticate */
1273   char *zAuthUser;              /* User name used to authenticate */
1274 };
1275 
1276 /* Allowed values for sqlite3_userauth.authLevel */
1277 #define UAUTH_Unknown     0     /* Authentication not yet checked */
1278 #define UAUTH_Fail        1     /* User authentication failed */
1279 #define UAUTH_User        2     /* Authenticated as a normal user */
1280 #define UAUTH_Admin       3     /* Authenticated as an administrator */
1281 
1282 /* Functions used only by user authorization logic */
1283 int sqlite3UserAuthTable(const char*);
1284 int sqlite3UserAuthCheckLogin(sqlite3*,const char*,u8*);
1285 void sqlite3UserAuthInit(sqlite3*);
1286 void sqlite3CryptFunc(sqlite3_context*,int,sqlite3_value**);
1287 
1288 #endif /* SQLITE_USER_AUTHENTICATION */
1289 
1290 /*
1291 ** typedef for the authorization callback function.
1292 */
1293 #ifdef SQLITE_USER_AUTHENTICATION
1294   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1295                                const char*, const char*);
1296 #else
1297   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1298                                const char*);
1299 #endif
1300 
1301 #ifndef SQLITE_OMIT_DEPRECATED
1302 /* This is an extra SQLITE_TRACE macro that indicates "legacy" tracing
1303 ** in the style of sqlite3_trace()
1304 */
1305 #define SQLITE_TRACE_LEGACY  0x80
1306 #else
1307 #define SQLITE_TRACE_LEGACY  0
1308 #endif /* SQLITE_OMIT_DEPRECATED */
1309 
1310 
1311 /*
1312 ** Each database connection is an instance of the following structure.
1313 */
1314 struct sqlite3 {
1315   sqlite3_vfs *pVfs;            /* OS Interface */
1316   struct Vdbe *pVdbe;           /* List of active virtual machines */
1317   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
1318   sqlite3_mutex *mutex;         /* Connection mutex */
1319   Db *aDb;                      /* All backends */
1320   int nDb;                      /* Number of backends currently in use */
1321   u32 mDbFlags;                 /* flags recording internal state */
1322   u32 flags;                    /* flags settable by pragmas. See below */
1323   i64 lastRowid;                /* ROWID of most recent insert (see above) */
1324   i64 szMmap;                   /* Default mmap_size setting */
1325   u32 nSchemaLock;              /* Do not reset the schema when non-zero */
1326   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
1327   int errCode;                  /* Most recent error code (SQLITE_*) */
1328   int errMask;                  /* & result codes with this before returning */
1329   int iSysErrno;                /* Errno value from last system error */
1330   u16 dbOptFlags;               /* Flags to enable/disable optimizations */
1331   u8 enc;                       /* Text encoding */
1332   u8 autoCommit;                /* The auto-commit flag. */
1333   u8 temp_store;                /* 1: file 2: memory 0: default */
1334   u8 mallocFailed;              /* True if we have seen a malloc failure */
1335   u8 bBenignMalloc;             /* Do not require OOMs if true */
1336   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
1337   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
1338   u8 suppressErr;               /* Do not issue error messages if true */
1339   u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
1340   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
1341   u8 mTrace;                    /* zero or more SQLITE_TRACE flags */
1342   u8 skipBtreeMutex;            /* True if no shared-cache backends */
1343   u8 nSqlExec;                  /* Number of pending OP_SqlExec opcodes */
1344   int nextPagesize;             /* Pagesize after VACUUM if >0 */
1345   u32 magic;                    /* Magic number for detect library misuse */
1346   int nChange;                  /* Value returned by sqlite3_changes() */
1347   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
1348   int aLimit[SQLITE_N_LIMIT];   /* Limits */
1349   int nMaxSorterMmap;           /* Maximum size of regions mapped by sorter */
1350   struct sqlite3InitInfo {      /* Information used during initialization */
1351     int newTnum;                /* Rootpage of table being initialized */
1352     u8 iDb;                     /* Which db file is being initialized */
1353     u8 busy;                    /* TRUE if currently initializing */
1354     u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
1355     u8 imposterTable;           /* Building an imposter table */
1356   } init;
1357   int nVdbeActive;              /* Number of VDBEs currently running */
1358   int nVdbeRead;                /* Number of active VDBEs that read or write */
1359   int nVdbeWrite;               /* Number of active VDBEs that read and write */
1360   int nVdbeExec;                /* Number of nested calls to VdbeExec() */
1361   int nVDestroy;                /* Number of active OP_VDestroy operations */
1362   int nExtension;               /* Number of loaded extensions */
1363   void **aExtension;            /* Array of shared library handles */
1364   int (*xTrace)(u32,void*,void*,void*);     /* Trace function */
1365   void *pTraceArg;                          /* Argument to the trace function */
1366   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
1367   void *pProfileArg;                        /* Argument to profile function */
1368   void *pCommitArg;                 /* Argument to xCommitCallback() */
1369   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
1370   void *pRollbackArg;               /* Argument to xRollbackCallback() */
1371   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
1372   void *pUpdateArg;
1373   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
1374 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
1375   void *pPreUpdateArg;          /* First argument to xPreUpdateCallback */
1376   void (*xPreUpdateCallback)(   /* Registered using sqlite3_preupdate_hook() */
1377     void*,sqlite3*,int,char const*,char const*,sqlite3_int64,sqlite3_int64
1378   );
1379   PreUpdate *pPreUpdate;        /* Context for active pre-update callback */
1380 #endif /* SQLITE_ENABLE_PREUPDATE_HOOK */
1381 #ifndef SQLITE_OMIT_WAL
1382   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
1383   void *pWalArg;
1384 #endif
1385   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
1386   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
1387   void *pCollNeededArg;
1388   sqlite3_value *pErr;          /* Most recent error message */
1389   union {
1390     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
1391     double notUsed1;            /* Spacer */
1392   } u1;
1393   Lookaside lookaside;          /* Lookaside malloc configuration */
1394 #ifndef SQLITE_OMIT_AUTHORIZATION
1395   sqlite3_xauth xAuth;          /* Access authorization function */
1396   void *pAuthArg;               /* 1st argument to the access auth function */
1397 #endif
1398 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
1399   int (*xProgress)(void *);     /* The progress callback */
1400   void *pProgressArg;           /* Argument to the progress callback */
1401   unsigned nProgressOps;        /* Number of opcodes for progress callback */
1402 #endif
1403 #ifndef SQLITE_OMIT_VIRTUALTABLE
1404   int nVTrans;                  /* Allocated size of aVTrans */
1405   Hash aModule;                 /* populated by sqlite3_create_module() */
1406   VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
1407   VTable **aVTrans;             /* Virtual tables with open transactions */
1408   VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
1409 #endif
1410   Hash aFunc;                   /* Hash table of connection functions */
1411   Hash aCollSeq;                /* All collating sequences */
1412   BusyHandler busyHandler;      /* Busy callback */
1413   Db aDbStatic[2];              /* Static space for the 2 default backends */
1414   Savepoint *pSavepoint;        /* List of active savepoints */
1415   int busyTimeout;              /* Busy handler timeout, in msec */
1416   int nSavepoint;               /* Number of non-transaction savepoints */
1417   int nStatement;               /* Number of nested statement-transactions  */
1418   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
1419   i64 nDeferredImmCons;         /* Net deferred immediate constraints */
1420   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
1421 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
1422   /* The following variables are all protected by the STATIC_MASTER
1423   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
1424   **
1425   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
1426   ** unlock so that it can proceed.
1427   **
1428   ** When X.pBlockingConnection==Y, that means that something that X tried
1429   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
1430   ** held by Y.
1431   */
1432   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
1433   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
1434   void *pUnlockArg;                     /* Argument to xUnlockNotify */
1435   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
1436   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
1437 #endif
1438 #ifdef SQLITE_USER_AUTHENTICATION
1439   sqlite3_userauth auth;        /* User authentication information */
1440 #endif
1441 };
1442 
1443 /*
1444 ** A macro to discover the encoding of a database.
1445 */
1446 #define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
1447 #define ENC(db)        ((db)->enc)
1448 
1449 /*
1450 ** Possible values for the sqlite3.flags.
1451 **
1452 ** Value constraints (enforced via assert()):
1453 **      SQLITE_FullFSync     == PAGER_FULLFSYNC
1454 **      SQLITE_CkptFullFSync == PAGER_CKPT_FULLFSYNC
1455 **      SQLITE_CacheSpill    == PAGER_CACHE_SPILL
1456 */
1457 #define SQLITE_WriteSchema    0x00000001  /* OK to update SQLITE_MASTER */
1458 #define SQLITE_LegacyFileFmt  0x00000002  /* Create new databases in format 1 */
1459 #define SQLITE_FullColNames   0x00000004  /* Show full column names on SELECT */
1460 #define SQLITE_FullFSync      0x00000008  /* Use full fsync on the backend */
1461 #define SQLITE_CkptFullFSync  0x00000010  /* Use full fsync for checkpoint */
1462 #define SQLITE_CacheSpill     0x00000020  /* OK to spill pager cache */
1463 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
1464 #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
1465                                           /*   DELETE, or UPDATE and return */
1466                                           /*   the count using a callback. */
1467 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
1468                                           /*   result set is empty */
1469 #define SQLITE_IgnoreChecks   0x00000200  /* Do not enforce check constraints */
1470 #define SQLITE_ReadUncommit   0x00000400  /* READ UNCOMMITTED in shared-cache */
1471 #define SQLITE_NoCkptOnClose  0x00000800  /* No checkpoint on close()/DETACH */
1472 #define SQLITE_ReverseOrder   0x00001000  /* Reverse unordered SELECTs */
1473 #define SQLITE_RecTriggers    0x00002000  /* Enable recursive triggers */
1474 #define SQLITE_ForeignKeys    0x00004000  /* Enforce foreign key constraints  */
1475 #define SQLITE_AutoIndex      0x00008000  /* Enable automatic indexes */
1476 #define SQLITE_LoadExtension  0x00010000  /* Enable load_extension */
1477 #define SQLITE_LoadExtFunc    0x00020000  /* Enable load_extension() SQL func */
1478 #define SQLITE_EnableTrigger  0x00040000  /* True to enable triggers */
1479 #define SQLITE_DeferFKs       0x00080000  /* Defer all FK constraints */
1480 #define SQLITE_QueryOnly      0x00100000  /* Disable database changes */
1481 #define SQLITE_CellSizeCk     0x00200000  /* Check btree cell sizes on load */
1482 #define SQLITE_Fts3Tokenizer  0x00400000  /* Enable fts3_tokenizer(2) */
1483 #define SQLITE_EnableQPSG     0x00800000  /* Query Planner Stability Guarantee */
1484 /* Flags used only if debugging */
1485 #ifdef SQLITE_DEBUG
1486 #define SQLITE_SqlTrace       0x08000000  /* Debug print SQL as it executes */
1487 #define SQLITE_VdbeListing    0x10000000  /* Debug listings of VDBE programs */
1488 #define SQLITE_VdbeTrace      0x20000000  /* True to trace VDBE execution */
1489 #define SQLITE_VdbeAddopTrace 0x40000000  /* Trace sqlite3VdbeAddOp() calls */
1490 #define SQLITE_VdbeEQP        0x80000000  /* Debug EXPLAIN QUERY PLAN */
1491 #endif
1492 
1493 /*
1494 ** Allowed values for sqlite3.mDbFlags
1495 */
1496 #define DBFLAG_SchemaChange   0x0001  /* Uncommitted Hash table changes */
1497 #define DBFLAG_PreferBuiltin  0x0002  /* Preference to built-in funcs */
1498 #define DBFLAG_Vacuum         0x0004  /* Currently in a VACUUM */
1499 
1500 /*
1501 ** Bits of the sqlite3.dbOptFlags field that are used by the
1502 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
1503 ** selectively disable various optimizations.
1504 */
1505 #define SQLITE_QueryFlattener 0x0001   /* Query flattening */
1506 #define SQLITE_ColumnCache    0x0002   /* Column cache */
1507 #define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
1508 #define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
1509 /*                not used    0x0010   // Was: SQLITE_IdxRealAsInt */
1510 #define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
1511 #define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
1512 #define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
1513 #define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
1514 #define SQLITE_Transitive     0x0200   /* Transitive constraints */
1515 #define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
1516 #define SQLITE_Stat34         0x0800   /* Use STAT3 or STAT4 data */
1517 #define SQLITE_CountOfView    0x1000   /* The count-of-view optimization */
1518 #define SQLITE_CursorHints    0x2000   /* Add OP_CursorHint opcodes */
1519 #define SQLITE_AllOpts        0xffff   /* All optimizations */
1520 
1521 /*
1522 ** Macros for testing whether or not optimizations are enabled or disabled.
1523 */
1524 #define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
1525 #define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
1526 
1527 /*
1528 ** Return true if it OK to factor constant expressions into the initialization
1529 ** code. The argument is a Parse object for the code generator.
1530 */
1531 #define ConstFactorOk(P) ((P)->okConstFactor)
1532 
1533 /*
1534 ** Possible values for the sqlite.magic field.
1535 ** The numbers are obtained at random and have no special meaning, other
1536 ** than being distinct from one another.
1537 */
1538 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
1539 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
1540 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
1541 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
1542 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
1543 #define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */
1544 
1545 /*
1546 ** Each SQL function is defined by an instance of the following
1547 ** structure.  For global built-in functions (ex: substr(), max(), count())
1548 ** a pointer to this structure is held in the sqlite3BuiltinFunctions object.
1549 ** For per-connection application-defined functions, a pointer to this
1550 ** structure is held in the db->aHash hash table.
1551 **
1552 ** The u.pHash field is used by the global built-ins.  The u.pDestructor
1553 ** field is used by per-connection app-def functions.
1554 */
1555 struct FuncDef {
1556   i8 nArg;             /* Number of arguments.  -1 means unlimited */
1557   u16 funcFlags;       /* Some combination of SQLITE_FUNC_* */
1558   void *pUserData;     /* User data parameter */
1559   FuncDef *pNext;      /* Next function with same name */
1560   void (*xSFunc)(sqlite3_context*,int,sqlite3_value**); /* func or agg-step */
1561   void (*xFinalize)(sqlite3_context*);                  /* Agg finalizer */
1562   const char *zName;   /* SQL name of the function. */
1563   union {
1564     FuncDef *pHash;      /* Next with a different name but the same hash */
1565     FuncDestructor *pDestructor;   /* Reference counted destructor function */
1566   } u;
1567 };
1568 
1569 /*
1570 ** This structure encapsulates a user-function destructor callback (as
1571 ** configured using create_function_v2()) and a reference counter. When
1572 ** create_function_v2() is called to create a function with a destructor,
1573 ** a single object of this type is allocated. FuncDestructor.nRef is set to
1574 ** the number of FuncDef objects created (either 1 or 3, depending on whether
1575 ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
1576 ** member of each of the new FuncDef objects is set to point to the allocated
1577 ** FuncDestructor.
1578 **
1579 ** Thereafter, when one of the FuncDef objects is deleted, the reference
1580 ** count on this object is decremented. When it reaches 0, the destructor
1581 ** is invoked and the FuncDestructor structure freed.
1582 */
1583 struct FuncDestructor {
1584   int nRef;
1585   void (*xDestroy)(void *);
1586   void *pUserData;
1587 };
1588 
1589 /*
1590 ** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
1591 ** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  And
1592 ** SQLITE_FUNC_CONSTANT must be the same as SQLITE_DETERMINISTIC.  There
1593 ** are assert() statements in the code to verify this.
1594 **
1595 ** Value constraints (enforced via assert()):
1596 **     SQLITE_FUNC_MINMAX    ==  NC_MinMaxAgg      == SF_MinMaxAgg
1597 **     SQLITE_FUNC_LENGTH    ==  OPFLAG_LENGTHARG
1598 **     SQLITE_FUNC_TYPEOF    ==  OPFLAG_TYPEOFARG
1599 **     SQLITE_FUNC_CONSTANT  ==  SQLITE_DETERMINISTIC from the API
1600 **     SQLITE_FUNC_ENCMASK   depends on SQLITE_UTF* macros in the API
1601 */
1602 #define SQLITE_FUNC_ENCMASK  0x0003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
1603 #define SQLITE_FUNC_LIKE     0x0004 /* Candidate for the LIKE optimization */
1604 #define SQLITE_FUNC_CASE     0x0008 /* Case-sensitive LIKE-type function */
1605 #define SQLITE_FUNC_EPHEM    0x0010 /* Ephemeral.  Delete with VDBE */
1606 #define SQLITE_FUNC_NEEDCOLL 0x0020 /* sqlite3GetFuncCollSeq() might be called*/
1607 #define SQLITE_FUNC_LENGTH   0x0040 /* Built-in length() function */
1608 #define SQLITE_FUNC_TYPEOF   0x0080 /* Built-in typeof() function */
1609 #define SQLITE_FUNC_COUNT    0x0100 /* Built-in count(*) aggregate */
1610 #define SQLITE_FUNC_COALESCE 0x0200 /* Built-in coalesce() or ifnull() */
1611 #define SQLITE_FUNC_UNLIKELY 0x0400 /* Built-in unlikely() function */
1612 #define SQLITE_FUNC_CONSTANT 0x0800 /* Constant inputs give a constant output */
1613 #define SQLITE_FUNC_MINMAX   0x1000 /* True for min() and max() aggregates */
1614 #define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
1615                                     ** single query - might change over time */
1616 #define SQLITE_FUNC_AFFINITY 0x4000 /* Built-in affinity() function */
1617 
1618 /*
1619 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
1620 ** used to create the initializers for the FuncDef structures.
1621 **
1622 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
1623 **     Used to create a scalar function definition of a function zName
1624 **     implemented by C function xFunc that accepts nArg arguments. The
1625 **     value passed as iArg is cast to a (void*) and made available
1626 **     as the user-data (sqlite3_user_data()) for the function. If
1627 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
1628 **
1629 **   VFUNCTION(zName, nArg, iArg, bNC, xFunc)
1630 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
1631 **
1632 **   DFUNCTION(zName, nArg, iArg, bNC, xFunc)
1633 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
1634 **     adds the SQLITE_FUNC_SLOCHNG flag.  Used for date & time functions
1635 **     and functions like sqlite_version() that can change, but not during
1636 **     a single query.  The iArg is ignored.  The user-data is always set
1637 **     to a NULL pointer.  The bNC parameter is not used.
1638 **
1639 **   PURE_DATE(zName, nArg, iArg, bNC, xFunc)
1640 **     Used for "pure" date/time functions, this macro is like DFUNCTION
1641 **     except that it does set the SQLITE_FUNC_CONSTANT flags.  iArg is
1642 **     ignored and the user-data for these functions is set to an
1643 **     arbitrary non-NULL pointer.  The bNC parameter is not used.
1644 **
1645 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
1646 **     Used to create an aggregate function definition implemented by
1647 **     the C functions xStep and xFinal. The first four parameters
1648 **     are interpreted in the same way as the first 4 parameters to
1649 **     FUNCTION().
1650 **
1651 **   LIKEFUNC(zName, nArg, pArg, flags)
1652 **     Used to create a scalar function definition of a function zName
1653 **     that accepts nArg arguments and is implemented by a call to C
1654 **     function likeFunc. Argument pArg is cast to a (void *) and made
1655 **     available as the function user-data (sqlite3_user_data()). The
1656 **     FuncDef.flags variable is set to the value passed as the flags
1657 **     parameter.
1658 */
1659 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1660   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1661    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, {0} }
1662 #define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1663   {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1664    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, {0} }
1665 #define DFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1666   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8, \
1667    0, 0, xFunc, 0, #zName, {0} }
1668 #define PURE_DATE(zName, nArg, iArg, bNC, xFunc) \
1669   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|SQLITE_FUNC_CONSTANT, \
1670    (void*)&sqlite3Config, 0, xFunc, 0, #zName, {0} }
1671 #define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
1672   {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
1673    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, {0} }
1674 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
1675   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1676    pArg, 0, xFunc, 0, #zName, }
1677 #define LIKEFUNC(zName, nArg, arg, flags) \
1678   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
1679    (void *)arg, 0, likeFunc, 0, #zName, {0} }
1680 #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
1681   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
1682    SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,#zName, {0}}
1683 #define AGGREGATE2(zName, nArg, arg, nc, xStep, xFinal, extraFlags) \
1684   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|extraFlags, \
1685    SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,#zName, {0}}
1686 
1687 /*
1688 ** All current savepoints are stored in a linked list starting at
1689 ** sqlite3.pSavepoint. The first element in the list is the most recently
1690 ** opened savepoint. Savepoints are added to the list by the vdbe
1691 ** OP_Savepoint instruction.
1692 */
1693 struct Savepoint {
1694   char *zName;                        /* Savepoint name (nul-terminated) */
1695   i64 nDeferredCons;                  /* Number of deferred fk violations */
1696   i64 nDeferredImmCons;               /* Number of deferred imm fk. */
1697   Savepoint *pNext;                   /* Parent savepoint (if any) */
1698 };
1699 
1700 /*
1701 ** The following are used as the second parameter to sqlite3Savepoint(),
1702 ** and as the P1 argument to the OP_Savepoint instruction.
1703 */
1704 #define SAVEPOINT_BEGIN      0
1705 #define SAVEPOINT_RELEASE    1
1706 #define SAVEPOINT_ROLLBACK   2
1707 
1708 
1709 /*
1710 ** Each SQLite module (virtual table definition) is defined by an
1711 ** instance of the following structure, stored in the sqlite3.aModule
1712 ** hash table.
1713 */
1714 struct Module {
1715   const sqlite3_module *pModule;       /* Callback pointers */
1716   const char *zName;                   /* Name passed to create_module() */
1717   void *pAux;                          /* pAux passed to create_module() */
1718   void (*xDestroy)(void *);            /* Module destructor function */
1719   Table *pEpoTab;                      /* Eponymous table for this module */
1720 };
1721 
1722 /*
1723 ** information about each column of an SQL table is held in an instance
1724 ** of this structure.
1725 */
1726 struct Column {
1727   char *zName;     /* Name of this column, \000, then the type */
1728   Expr *pDflt;     /* Default value of this column */
1729   char *zColl;     /* Collating sequence.  If NULL, use the default */
1730   u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
1731   char affinity;   /* One of the SQLITE_AFF_... values */
1732   u8 szEst;        /* Estimated size of value in this column. sizeof(INT)==1 */
1733   u8 colFlags;     /* Boolean properties.  See COLFLAG_ defines below */
1734 };
1735 
1736 /* Allowed values for Column.colFlags:
1737 */
1738 #define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
1739 #define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */
1740 #define COLFLAG_HASTYPE  0x0004    /* Type name follows column name */
1741 
1742 /*
1743 ** A "Collating Sequence" is defined by an instance of the following
1744 ** structure. Conceptually, a collating sequence consists of a name and
1745 ** a comparison routine that defines the order of that sequence.
1746 **
1747 ** If CollSeq.xCmp is NULL, it means that the
1748 ** collating sequence is undefined.  Indices built on an undefined
1749 ** collating sequence may not be read or written.
1750 */
1751 struct CollSeq {
1752   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
1753   u8 enc;               /* Text encoding handled by xCmp() */
1754   void *pUser;          /* First argument to xCmp() */
1755   int (*xCmp)(void*,int, const void*, int, const void*);
1756   void (*xDel)(void*);  /* Destructor for pUser */
1757 };
1758 
1759 /*
1760 ** A sort order can be either ASC or DESC.
1761 */
1762 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
1763 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
1764 #define SQLITE_SO_UNDEFINED -1 /* No sort order specified */
1765 
1766 /*
1767 ** Column affinity types.
1768 **
1769 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
1770 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
1771 ** the speed a little by numbering the values consecutively.
1772 **
1773 ** But rather than start with 0 or 1, we begin with 'A'.  That way,
1774 ** when multiple affinity types are concatenated into a string and
1775 ** used as the P4 operand, they will be more readable.
1776 **
1777 ** Note also that the numeric types are grouped together so that testing
1778 ** for a numeric type is a single comparison.  And the BLOB type is first.
1779 */
1780 #define SQLITE_AFF_BLOB     'A'
1781 #define SQLITE_AFF_TEXT     'B'
1782 #define SQLITE_AFF_NUMERIC  'C'
1783 #define SQLITE_AFF_INTEGER  'D'
1784 #define SQLITE_AFF_REAL     'E'
1785 
1786 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
1787 
1788 /*
1789 ** The SQLITE_AFF_MASK values masks off the significant bits of an
1790 ** affinity value.
1791 */
1792 #define SQLITE_AFF_MASK     0x47
1793 
1794 /*
1795 ** Additional bit values that can be ORed with an affinity without
1796 ** changing the affinity.
1797 **
1798 ** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
1799 ** It causes an assert() to fire if either operand to a comparison
1800 ** operator is NULL.  It is added to certain comparison operators to
1801 ** prove that the operands are always NOT NULL.
1802 */
1803 #define SQLITE_KEEPNULL     0x08  /* Used by vector == or <> */
1804 #define SQLITE_JUMPIFNULL   0x10  /* jumps if either operand is NULL */
1805 #define SQLITE_STOREP2      0x20  /* Store result in reg[P2] rather than jump */
1806 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
1807 #define SQLITE_NOTNULL      0x90  /* Assert that operands are never NULL */
1808 
1809 /*
1810 ** An object of this type is created for each virtual table present in
1811 ** the database schema.
1812 **
1813 ** If the database schema is shared, then there is one instance of this
1814 ** structure for each database connection (sqlite3*) that uses the shared
1815 ** schema. This is because each database connection requires its own unique
1816 ** instance of the sqlite3_vtab* handle used to access the virtual table
1817 ** implementation. sqlite3_vtab* handles can not be shared between
1818 ** database connections, even when the rest of the in-memory database
1819 ** schema is shared, as the implementation often stores the database
1820 ** connection handle passed to it via the xConnect() or xCreate() method
1821 ** during initialization internally. This database connection handle may
1822 ** then be used by the virtual table implementation to access real tables
1823 ** within the database. So that they appear as part of the callers
1824 ** transaction, these accesses need to be made via the same database
1825 ** connection as that used to execute SQL operations on the virtual table.
1826 **
1827 ** All VTable objects that correspond to a single table in a shared
1828 ** database schema are initially stored in a linked-list pointed to by
1829 ** the Table.pVTable member variable of the corresponding Table object.
1830 ** When an sqlite3_prepare() operation is required to access the virtual
1831 ** table, it searches the list for the VTable that corresponds to the
1832 ** database connection doing the preparing so as to use the correct
1833 ** sqlite3_vtab* handle in the compiled query.
1834 **
1835 ** When an in-memory Table object is deleted (for example when the
1836 ** schema is being reloaded for some reason), the VTable objects are not
1837 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
1838 ** immediately. Instead, they are moved from the Table.pVTable list to
1839 ** another linked list headed by the sqlite3.pDisconnect member of the
1840 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
1841 ** next time a statement is prepared using said sqlite3*. This is done
1842 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
1843 ** Refer to comments above function sqlite3VtabUnlockList() for an
1844 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
1845 ** list without holding the corresponding sqlite3.mutex mutex.
1846 **
1847 ** The memory for objects of this type is always allocated by
1848 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
1849 ** the first argument.
1850 */
1851 struct VTable {
1852   sqlite3 *db;              /* Database connection associated with this table */
1853   Module *pMod;             /* Pointer to module implementation */
1854   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
1855   int nRef;                 /* Number of pointers to this structure */
1856   u8 bConstraint;           /* True if constraints are supported */
1857   int iSavepoint;           /* Depth of the SAVEPOINT stack */
1858   VTable *pNext;            /* Next in linked list (see above) */
1859 };
1860 
1861 /*
1862 ** The schema for each SQL table and view is represented in memory
1863 ** by an instance of the following structure.
1864 */
1865 struct Table {
1866   char *zName;         /* Name of the table or view */
1867   Column *aCol;        /* Information about each column */
1868   Index *pIndex;       /* List of SQL indexes on this table. */
1869   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
1870   FKey *pFKey;         /* Linked list of all foreign keys in this table */
1871   char *zColAff;       /* String defining the affinity of each column */
1872   ExprList *pCheck;    /* All CHECK constraints */
1873                        /*   ... also used as column name list in a VIEW */
1874   int tnum;            /* Root BTree page for this table */
1875   u32 nTabRef;         /* Number of pointers to this Table */
1876   u32 tabFlags;        /* Mask of TF_* values */
1877   i16 iPKey;           /* If not negative, use aCol[iPKey] as the rowid */
1878   i16 nCol;            /* Number of columns in this table */
1879   LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
1880   LogEst szTabRow;     /* Estimated size of each table row in bytes */
1881 #ifdef SQLITE_ENABLE_COSTMULT
1882   LogEst costMult;     /* Cost multiplier for using this table */
1883 #endif
1884   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
1885 #ifndef SQLITE_OMIT_ALTERTABLE
1886   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
1887 #endif
1888 #ifndef SQLITE_OMIT_VIRTUALTABLE
1889   int nModuleArg;      /* Number of arguments to the module */
1890   char **azModuleArg;  /* 0: module 1: schema 2: vtab name 3...: args */
1891   VTable *pVTable;     /* List of VTable objects. */
1892 #endif
1893   Trigger *pTrigger;   /* List of triggers stored in pSchema */
1894   Schema *pSchema;     /* Schema that contains this table */
1895   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
1896 };
1897 
1898 /*
1899 ** Allowed values for Table.tabFlags.
1900 **
1901 ** TF_OOOHidden applies to tables or view that have hidden columns that are
1902 ** followed by non-hidden columns.  Example:  "CREATE VIRTUAL TABLE x USING
1903 ** vtab1(a HIDDEN, b);".  Since "b" is a non-hidden column but "a" is hidden,
1904 ** the TF_OOOHidden attribute would apply in this case.  Such tables require
1905 ** special handling during INSERT processing.
1906 */
1907 #define TF_Readonly        0x0001    /* Read-only system table */
1908 #define TF_Ephemeral       0x0002    /* An ephemeral table */
1909 #define TF_HasPrimaryKey   0x0004    /* Table has a primary key */
1910 #define TF_Autoincrement   0x0008    /* Integer primary key is autoincrement */
1911 #define TF_HasStat1        0x0010    /* nRowLogEst set from sqlite_stat1 */
1912 #define TF_WithoutRowid    0x0020    /* No rowid.  PRIMARY KEY is the key */
1913 #define TF_NoVisibleRowid  0x0040    /* No user-visible "rowid" column */
1914 #define TF_OOOHidden       0x0080    /* Out-of-Order hidden columns */
1915 #define TF_StatsUsed       0x0100    /* Query planner decisions affected by
1916                                      ** Index.aiRowLogEst[] values */
1917 #define TF_HasNotNull      0x0200    /* Contains NOT NULL constraints */
1918 
1919 /*
1920 ** Test to see whether or not a table is a virtual table.  This is
1921 ** done as a macro so that it will be optimized out when virtual
1922 ** table support is omitted from the build.
1923 */
1924 #ifndef SQLITE_OMIT_VIRTUALTABLE
1925 #  define IsVirtual(X)      ((X)->nModuleArg)
1926 #else
1927 #  define IsVirtual(X)      0
1928 #endif
1929 
1930 /*
1931 ** Macros to determine if a column is hidden.  IsOrdinaryHiddenColumn()
1932 ** only works for non-virtual tables (ordinary tables and views) and is
1933 ** always false unless SQLITE_ENABLE_HIDDEN_COLUMNS is defined.  The
1934 ** IsHiddenColumn() macro is general purpose.
1935 */
1936 #if defined(SQLITE_ENABLE_HIDDEN_COLUMNS)
1937 #  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1938 #  define IsOrdinaryHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1939 #elif !defined(SQLITE_OMIT_VIRTUALTABLE)
1940 #  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1941 #  define IsOrdinaryHiddenColumn(X) 0
1942 #else
1943 #  define IsHiddenColumn(X)         0
1944 #  define IsOrdinaryHiddenColumn(X) 0
1945 #endif
1946 
1947 
1948 /* Does the table have a rowid */
1949 #define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
1950 #define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)
1951 
1952 /*
1953 ** Each foreign key constraint is an instance of the following structure.
1954 **
1955 ** A foreign key is associated with two tables.  The "from" table is
1956 ** the table that contains the REFERENCES clause that creates the foreign
1957 ** key.  The "to" table is the table that is named in the REFERENCES clause.
1958 ** Consider this example:
1959 **
1960 **     CREATE TABLE ex1(
1961 **       a INTEGER PRIMARY KEY,
1962 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
1963 **     );
1964 **
1965 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
1966 ** Equivalent names:
1967 **
1968 **     from-table == child-table
1969 **       to-table == parent-table
1970 **
1971 ** Each REFERENCES clause generates an instance of the following structure
1972 ** which is attached to the from-table.  The to-table need not exist when
1973 ** the from-table is created.  The existence of the to-table is not checked.
1974 **
1975 ** The list of all parents for child Table X is held at X.pFKey.
1976 **
1977 ** A list of all children for a table named Z (which might not even exist)
1978 ** is held in Schema.fkeyHash with a hash key of Z.
1979 */
1980 struct FKey {
1981   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
1982   FKey *pNextFrom;  /* Next FKey with the same in pFrom. Next parent of pFrom */
1983   char *zTo;        /* Name of table that the key points to (aka: Parent) */
1984   FKey *pNextTo;    /* Next with the same zTo. Next child of zTo. */
1985   FKey *pPrevTo;    /* Previous with the same zTo */
1986   int nCol;         /* Number of columns in this key */
1987   /* EV: R-30323-21917 */
1988   u8 isDeferred;       /* True if constraint checking is deferred till COMMIT */
1989   u8 aAction[2];        /* ON DELETE and ON UPDATE actions, respectively */
1990   Trigger *apTrigger[2];/* Triggers for aAction[] actions */
1991   struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
1992     int iFrom;            /* Index of column in pFrom */
1993     char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
1994   } aCol[1];            /* One entry for each of nCol columns */
1995 };
1996 
1997 /*
1998 ** SQLite supports many different ways to resolve a constraint
1999 ** error.  ROLLBACK processing means that a constraint violation
2000 ** causes the operation in process to fail and for the current transaction
2001 ** to be rolled back.  ABORT processing means the operation in process
2002 ** fails and any prior changes from that one operation are backed out,
2003 ** but the transaction is not rolled back.  FAIL processing means that
2004 ** the operation in progress stops and returns an error code.  But prior
2005 ** changes due to the same operation are not backed out and no rollback
2006 ** occurs.  IGNORE means that the particular row that caused the constraint
2007 ** error is not inserted or updated.  Processing continues and no error
2008 ** is returned.  REPLACE means that preexisting database rows that caused
2009 ** a UNIQUE constraint violation are removed so that the new insert or
2010 ** update can proceed.  Processing continues and no error is reported.
2011 **
2012 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
2013 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
2014 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
2015 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
2016 ** referenced table row is propagated into the row that holds the
2017 ** foreign key.
2018 **
2019 ** The following symbolic values are used to record which type
2020 ** of action to take.
2021 */
2022 #define OE_None     0   /* There is no constraint to check */
2023 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
2024 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
2025 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
2026 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
2027 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
2028 
2029 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
2030 #define OE_SetNull  7   /* Set the foreign key value to NULL */
2031 #define OE_SetDflt  8   /* Set the foreign key value to its default */
2032 #define OE_Cascade  9   /* Cascade the changes */
2033 
2034 #define OE_Default  10  /* Do whatever the default action is */
2035 
2036 
2037 /*
2038 ** An instance of the following structure is passed as the first
2039 ** argument to sqlite3VdbeKeyCompare and is used to control the
2040 ** comparison of the two index keys.
2041 **
2042 ** Note that aSortOrder[] and aColl[] have nField+1 slots.  There
2043 ** are nField slots for the columns of an index then one extra slot
2044 ** for the rowid at the end.
2045 */
2046 struct KeyInfo {
2047   u32 nRef;           /* Number of references to this KeyInfo object */
2048   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
2049   u16 nKeyField;      /* Number of key columns in the index */
2050   u16 nAllField;      /* Total columns, including key plus others */
2051   sqlite3 *db;        /* The database connection */
2052   u8 *aSortOrder;     /* Sort order for each column. */
2053   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
2054 };
2055 
2056 /*
2057 ** This object holds a record which has been parsed out into individual
2058 ** fields, for the purposes of doing a comparison.
2059 **
2060 ** A record is an object that contains one or more fields of data.
2061 ** Records are used to store the content of a table row and to store
2062 ** the key of an index.  A blob encoding of a record is created by
2063 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
2064 ** OP_Column opcode.
2065 **
2066 ** An instance of this object serves as a "key" for doing a search on
2067 ** an index b+tree. The goal of the search is to find the entry that
2068 ** is closed to the key described by this object.  This object might hold
2069 ** just a prefix of the key.  The number of fields is given by
2070 ** pKeyInfo->nField.
2071 **
2072 ** The r1 and r2 fields are the values to return if this key is less than
2073 ** or greater than a key in the btree, respectively.  These are normally
2074 ** -1 and +1 respectively, but might be inverted to +1 and -1 if the b-tree
2075 ** is in DESC order.
2076 **
2077 ** The key comparison functions actually return default_rc when they find
2078 ** an equals comparison.  default_rc can be -1, 0, or +1.  If there are
2079 ** multiple entries in the b-tree with the same key (when only looking
2080 ** at the first pKeyInfo->nFields,) then default_rc can be set to -1 to
2081 ** cause the search to find the last match, or +1 to cause the search to
2082 ** find the first match.
2083 **
2084 ** The key comparison functions will set eqSeen to true if they ever
2085 ** get and equal results when comparing this structure to a b-tree record.
2086 ** When default_rc!=0, the search might end up on the record immediately
2087 ** before the first match or immediately after the last match.  The
2088 ** eqSeen field will indicate whether or not an exact match exists in the
2089 ** b-tree.
2090 */
2091 struct UnpackedRecord {
2092   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
2093   Mem *aMem;          /* Values */
2094   u16 nField;         /* Number of entries in apMem[] */
2095   i8 default_rc;      /* Comparison result if keys are equal */
2096   u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
2097   i8 r1;              /* Value to return if (lhs < rhs) */
2098   i8 r2;              /* Value to return if (lhs > rhs) */
2099   u8 eqSeen;          /* True if an equality comparison has been seen */
2100 };
2101 
2102 
2103 /*
2104 ** Each SQL index is represented in memory by an
2105 ** instance of the following structure.
2106 **
2107 ** The columns of the table that are to be indexed are described
2108 ** by the aiColumn[] field of this structure.  For example, suppose
2109 ** we have the following table and index:
2110 **
2111 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
2112 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
2113 **
2114 ** In the Table structure describing Ex1, nCol==3 because there are
2115 ** three columns in the table.  In the Index structure describing
2116 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
2117 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
2118 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
2119 ** The second column to be indexed (c1) has an index of 0 in
2120 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
2121 **
2122 ** The Index.onError field determines whether or not the indexed columns
2123 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
2124 ** it means this is not a unique index.  Otherwise it is a unique index
2125 ** and the value of Index.onError indicate the which conflict resolution
2126 ** algorithm to employ whenever an attempt is made to insert a non-unique
2127 ** element.
2128 **
2129 ** While parsing a CREATE TABLE or CREATE INDEX statement in order to
2130 ** generate VDBE code (as opposed to parsing one read from an sqlite_master
2131 ** table as part of parsing an existing database schema), transient instances
2132 ** of this structure may be created. In this case the Index.tnum variable is
2133 ** used to store the address of a VDBE instruction, not a database page
2134 ** number (it cannot - the database page is not allocated until the VDBE
2135 ** program is executed). See convertToWithoutRowidTable() for details.
2136 */
2137 struct Index {
2138   char *zName;             /* Name of this index */
2139   i16 *aiColumn;           /* Which columns are used by this index.  1st is 0 */
2140   LogEst *aiRowLogEst;     /* From ANALYZE: Est. rows selected by each column */
2141   Table *pTable;           /* The SQL table being indexed */
2142   char *zColAff;           /* String defining the affinity of each column */
2143   Index *pNext;            /* The next index associated with the same table */
2144   Schema *pSchema;         /* Schema containing this index */
2145   u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
2146   const char **azColl;     /* Array of collation sequence names for index */
2147   Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
2148   ExprList *aColExpr;      /* Column expressions */
2149   int tnum;                /* DB Page containing root of this index */
2150   LogEst szIdxRow;         /* Estimated average row size in bytes */
2151   u16 nKeyCol;             /* Number of columns forming the key */
2152   u16 nColumn;             /* Number of columns stored in the index */
2153   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
2154   unsigned idxType:2;      /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
2155   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
2156   unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
2157   unsigned isResized:1;    /* True if resizeIndexObject() has been called */
2158   unsigned isCovering:1;   /* True if this is a covering index */
2159   unsigned noSkipScan:1;   /* Do not try to use skip-scan if true */
2160   unsigned hasStat1:1;     /* aiRowLogEst values come from sqlite_stat1 */
2161 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
2162   int nSample;             /* Number of elements in aSample[] */
2163   int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
2164   tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
2165   IndexSample *aSample;    /* Samples of the left-most key */
2166   tRowcnt *aiRowEst;       /* Non-logarithmic stat1 data for this index */
2167   tRowcnt nRowEst0;        /* Non-logarithmic number of rows in the index */
2168 #endif
2169 };
2170 
2171 /*
2172 ** Allowed values for Index.idxType
2173 */
2174 #define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
2175 #define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */
2176 #define SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */
2177 
2178 /* Return true if index X is a PRIMARY KEY index */
2179 #define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
2180 
2181 /* Return true if index X is a UNIQUE index */
2182 #define IsUniqueIndex(X)      ((X)->onError!=OE_None)
2183 
2184 /* The Index.aiColumn[] values are normally positive integer.  But
2185 ** there are some negative values that have special meaning:
2186 */
2187 #define XN_ROWID     (-1)     /* Indexed column is the rowid */
2188 #define XN_EXPR      (-2)     /* Indexed column is an expression */
2189 
2190 /*
2191 ** Each sample stored in the sqlite_stat3 table is represented in memory
2192 ** using a structure of this type.  See documentation at the top of the
2193 ** analyze.c source file for additional information.
2194 */
2195 struct IndexSample {
2196   void *p;          /* Pointer to sampled record */
2197   int n;            /* Size of record in bytes */
2198   tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
2199   tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
2200   tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
2201 };
2202 
2203 /*
2204 ** Each token coming out of the lexer is an instance of
2205 ** this structure.  Tokens are also used as part of an expression.
2206 **
2207 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
2208 ** may contain random values.  Do not make any assumptions about Token.dyn
2209 ** and Token.n when Token.z==0.
2210 */
2211 struct Token {
2212   const char *z;     /* Text of the token.  Not NULL-terminated! */
2213   unsigned int n;    /* Number of characters in this token */
2214 };
2215 
2216 /*
2217 ** An instance of this structure contains information needed to generate
2218 ** code for a SELECT that contains aggregate functions.
2219 **
2220 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
2221 ** pointer to this structure.  The Expr.iColumn field is the index in
2222 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
2223 ** code for that node.
2224 **
2225 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
2226 ** original Select structure that describes the SELECT statement.  These
2227 ** fields do not need to be freed when deallocating the AggInfo structure.
2228 */
2229 struct AggInfo {
2230   u8 directMode;          /* Direct rendering mode means take data directly
2231                           ** from source tables rather than from accumulators */
2232   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
2233                           ** than the source table */
2234   int sortingIdx;         /* Cursor number of the sorting index */
2235   int sortingIdxPTab;     /* Cursor number of pseudo-table */
2236   int nSortingColumn;     /* Number of columns in the sorting index */
2237   int mnReg, mxReg;       /* Range of registers allocated for aCol and aFunc */
2238   ExprList *pGroupBy;     /* The group by clause */
2239   struct AggInfo_col {    /* For each column used in source tables */
2240     Table *pTab;             /* Source table */
2241     int iTable;              /* Cursor number of the source table */
2242     int iColumn;             /* Column number within the source table */
2243     int iSorterColumn;       /* Column number in the sorting index */
2244     int iMem;                /* Memory location that acts as accumulator */
2245     Expr *pExpr;             /* The original expression */
2246   } *aCol;
2247   int nColumn;            /* Number of used entries in aCol[] */
2248   int nAccumulator;       /* Number of columns that show through to the output.
2249                           ** Additional columns are used only as parameters to
2250                           ** aggregate functions */
2251   struct AggInfo_func {   /* For each aggregate function */
2252     Expr *pExpr;             /* Expression encoding the function */
2253     FuncDef *pFunc;          /* The aggregate function implementation */
2254     int iMem;                /* Memory location that acts as accumulator */
2255     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
2256   } *aFunc;
2257   int nFunc;              /* Number of entries in aFunc[] */
2258 };
2259 
2260 /*
2261 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
2262 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
2263 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
2264 ** it uses less memory in the Expr object, which is a big memory user
2265 ** in systems with lots of prepared statements.  And few applications
2266 ** need more than about 10 or 20 variables.  But some extreme users want
2267 ** to have prepared statements with over 32767 variables, and for them
2268 ** the option is available (at compile-time).
2269 */
2270 #if SQLITE_MAX_VARIABLE_NUMBER<=32767
2271 typedef i16 ynVar;
2272 #else
2273 typedef int ynVar;
2274 #endif
2275 
2276 /*
2277 ** Each node of an expression in the parse tree is an instance
2278 ** of this structure.
2279 **
2280 ** Expr.op is the opcode. The integer parser token codes are reused
2281 ** as opcodes here. For example, the parser defines TK_GE to be an integer
2282 ** code representing the ">=" operator. This same integer code is reused
2283 ** to represent the greater-than-or-equal-to operator in the expression
2284 ** tree.
2285 **
2286 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
2287 ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
2288 ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
2289 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
2290 ** then Expr.token contains the name of the function.
2291 **
2292 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
2293 ** binary operator. Either or both may be NULL.
2294 **
2295 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
2296 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
2297 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
2298 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
2299 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
2300 ** valid.
2301 **
2302 ** An expression of the form ID or ID.ID refers to a column in a table.
2303 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
2304 ** the integer cursor number of a VDBE cursor pointing to that table and
2305 ** Expr.iColumn is the column number for the specific column.  If the
2306 ** expression is used as a result in an aggregate SELECT, then the
2307 ** value is also stored in the Expr.iAgg column in the aggregate so that
2308 ** it can be accessed after all aggregates are computed.
2309 **
2310 ** If the expression is an unbound variable marker (a question mark
2311 ** character '?' in the original SQL) then the Expr.iTable holds the index
2312 ** number for that variable.
2313 **
2314 ** If the expression is a subquery then Expr.iColumn holds an integer
2315 ** register number containing the result of the subquery.  If the
2316 ** subquery gives a constant result, then iTable is -1.  If the subquery
2317 ** gives a different answer at different times during statement processing
2318 ** then iTable is the address of a subroutine that computes the subquery.
2319 **
2320 ** If the Expr is of type OP_Column, and the table it is selecting from
2321 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
2322 ** corresponding table definition.
2323 **
2324 ** ALLOCATION NOTES:
2325 **
2326 ** Expr objects can use a lot of memory space in database schema.  To
2327 ** help reduce memory requirements, sometimes an Expr object will be
2328 ** truncated.  And to reduce the number of memory allocations, sometimes
2329 ** two or more Expr objects will be stored in a single memory allocation,
2330 ** together with Expr.zToken strings.
2331 **
2332 ** If the EP_Reduced and EP_TokenOnly flags are set when
2333 ** an Expr object is truncated.  When EP_Reduced is set, then all
2334 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
2335 ** are contained within the same memory allocation.  Note, however, that
2336 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
2337 ** allocated, regardless of whether or not EP_Reduced is set.
2338 */
2339 struct Expr {
2340   u8 op;                 /* Operation performed by this node */
2341   char affinity;         /* The affinity of the column or 0 if not a column */
2342   u32 flags;             /* Various flags.  EP_* See below */
2343   union {
2344     char *zToken;          /* Token value. Zero terminated and dequoted */
2345     int iValue;            /* Non-negative integer value if EP_IntValue */
2346   } u;
2347 
2348   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
2349   ** space is allocated for the fields below this point. An attempt to
2350   ** access them will result in a segfault or malfunction.
2351   *********************************************************************/
2352 
2353   Expr *pLeft;           /* Left subnode */
2354   Expr *pRight;          /* Right subnode */
2355   union {
2356     ExprList *pList;     /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
2357     Select *pSelect;     /* EP_xIsSelect and op = IN, EXISTS, SELECT */
2358   } x;
2359 
2360   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
2361   ** space is allocated for the fields below this point. An attempt to
2362   ** access them will result in a segfault or malfunction.
2363   *********************************************************************/
2364 
2365 #if SQLITE_MAX_EXPR_DEPTH>0
2366   int nHeight;           /* Height of the tree headed by this node */
2367 #endif
2368   int iTable;            /* TK_COLUMN: cursor number of table holding column
2369                          ** TK_REGISTER: register number
2370                          ** TK_TRIGGER: 1 -> new, 0 -> old
2371                          ** EP_Unlikely:  134217728 times likelihood
2372                          ** TK_SELECT: 1st register of result vector */
2373   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
2374                          ** TK_VARIABLE: variable number (always >= 1).
2375                          ** TK_SELECT_COLUMN: column of the result vector */
2376   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
2377   i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
2378   u8 op2;                /* TK_REGISTER: original value of Expr.op
2379                          ** TK_COLUMN: the value of p5 for OP_Column
2380                          ** TK_AGG_FUNCTION: nesting depth */
2381   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
2382   Table *pTab;           /* Table for TK_COLUMN expressions.  Can be NULL
2383                          ** for a column of an index on an expression */
2384 };
2385 
2386 /*
2387 ** The following are the meanings of bits in the Expr.flags field.
2388 */
2389 #define EP_FromJoin  0x000001 /* Originates in ON/USING clause of outer join */
2390 #define EP_Agg       0x000002 /* Contains one or more aggregate functions */
2391                   /* 0x000004 // available for use */
2392                   /* 0x000008 // available for use */
2393 #define EP_Distinct  0x000010 /* Aggregate function with DISTINCT keyword */
2394 #define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
2395 #define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
2396 #define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
2397 #define EP_Collate   0x000100 /* Tree contains a TK_COLLATE operator */
2398 #define EP_Generic   0x000200 /* Ignore COLLATE or affinity on this tree */
2399 #define EP_IntValue  0x000400 /* Integer value contained in u.iValue */
2400 #define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
2401 #define EP_Skip      0x001000 /* COLLATE, AS, or UNLIKELY */
2402 #define EP_Reduced   0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
2403 #define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
2404 #define EP_Static    0x008000 /* Held in memory not obtained from malloc() */
2405 #define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
2406 #define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
2407 #define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
2408 #define EP_ConstFunc 0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
2409 #define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
2410 #define EP_Subquery  0x200000 /* Tree contains a TK_SELECT operator */
2411 #define EP_Alias     0x400000 /* Is an alias for a result set column */
2412 #define EP_Leaf      0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
2413 
2414 /*
2415 ** Combinations of two or more EP_* flags
2416 */
2417 #define EP_Propagate (EP_Collate|EP_Subquery) /* Propagate these bits up tree */
2418 
2419 /*
2420 ** These macros can be used to test, set, or clear bits in the
2421 ** Expr.flags field.
2422 */
2423 #define ExprHasProperty(E,P)     (((E)->flags&(P))!=0)
2424 #define ExprHasAllProperty(E,P)  (((E)->flags&(P))==(P))
2425 #define ExprSetProperty(E,P)     (E)->flags|=(P)
2426 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
2427 
2428 /* The ExprSetVVAProperty() macro is used for Verification, Validation,
2429 ** and Accreditation only.  It works like ExprSetProperty() during VVA
2430 ** processes but is a no-op for delivery.
2431 */
2432 #ifdef SQLITE_DEBUG
2433 # define ExprSetVVAProperty(E,P)  (E)->flags|=(P)
2434 #else
2435 # define ExprSetVVAProperty(E,P)
2436 #endif
2437 
2438 /*
2439 ** Macros to determine the number of bytes required by a normal Expr
2440 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
2441 ** and an Expr struct with the EP_TokenOnly flag set.
2442 */
2443 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
2444 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
2445 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
2446 
2447 /*
2448 ** Flags passed to the sqlite3ExprDup() function. See the header comment
2449 ** above sqlite3ExprDup() for details.
2450 */
2451 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
2452 
2453 /*
2454 ** A list of expressions.  Each expression may optionally have a
2455 ** name.  An expr/name combination can be used in several ways, such
2456 ** as the list of "expr AS ID" fields following a "SELECT" or in the
2457 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
2458 ** also be used as the argument to a function, in which case the a.zName
2459 ** field is not used.
2460 **
2461 ** By default the Expr.zSpan field holds a human-readable description of
2462 ** the expression that is used in the generation of error messages and
2463 ** column labels.  In this case, Expr.zSpan is typically the text of a
2464 ** column expression as it exists in a SELECT statement.  However, if
2465 ** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
2466 ** of the result column in the form: DATABASE.TABLE.COLUMN.  This later
2467 ** form is used for name resolution with nested FROM clauses.
2468 */
2469 struct ExprList {
2470   int nExpr;             /* Number of expressions on the list */
2471   struct ExprList_item { /* For each expression in the list */
2472     Expr *pExpr;            /* The parse tree for this expression */
2473     char *zName;            /* Token associated with this expression */
2474     char *zSpan;            /* Original text of the expression */
2475     u8 sortOrder;           /* 1 for DESC or 0 for ASC */
2476     unsigned done :1;       /* A flag to indicate when processing is finished */
2477     unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
2478     unsigned reusable :1;   /* Constant expression is reusable */
2479     union {
2480       struct {
2481         u16 iOrderByCol;      /* For ORDER BY, column number in result set */
2482         u16 iAlias;           /* Index into Parse.aAlias[] for zName */
2483       } x;
2484       int iConstExprReg;      /* Register in which Expr value is cached */
2485     } u;
2486   } a[1];                  /* One slot for each expression in the list */
2487 };
2488 
2489 /*
2490 ** An instance of this structure is used by the parser to record both
2491 ** the parse tree for an expression and the span of input text for an
2492 ** expression.
2493 */
2494 struct ExprSpan {
2495   Expr *pExpr;          /* The expression parse tree */
2496   const char *zStart;   /* First character of input text */
2497   const char *zEnd;     /* One character past the end of input text */
2498 };
2499 
2500 /*
2501 ** An instance of this structure can hold a simple list of identifiers,
2502 ** such as the list "a,b,c" in the following statements:
2503 **
2504 **      INSERT INTO t(a,b,c) VALUES ...;
2505 **      CREATE INDEX idx ON t(a,b,c);
2506 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
2507 **
2508 ** The IdList.a.idx field is used when the IdList represents the list of
2509 ** column names after a table name in an INSERT statement.  In the statement
2510 **
2511 **     INSERT INTO t(a,b,c) ...
2512 **
2513 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
2514 */
2515 struct IdList {
2516   struct IdList_item {
2517     char *zName;      /* Name of the identifier */
2518     int idx;          /* Index in some Table.aCol[] of a column named zName */
2519   } *a;
2520   int nId;         /* Number of identifiers on the list */
2521 };
2522 
2523 /*
2524 ** The bitmask datatype defined below is used for various optimizations.
2525 **
2526 ** Changing this from a 64-bit to a 32-bit type limits the number of
2527 ** tables in a join to 32 instead of 64.  But it also reduces the size
2528 ** of the library by 738 bytes on ix86.
2529 */
2530 #ifdef SQLITE_BITMASK_TYPE
2531   typedef SQLITE_BITMASK_TYPE Bitmask;
2532 #else
2533   typedef u64 Bitmask;
2534 #endif
2535 
2536 /*
2537 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
2538 */
2539 #define BMS  ((int)(sizeof(Bitmask)*8))
2540 
2541 /*
2542 ** A bit in a Bitmask
2543 */
2544 #define MASKBIT(n)   (((Bitmask)1)<<(n))
2545 #define MASKBIT32(n) (((unsigned int)1)<<(n))
2546 #define ALLBITS      ((Bitmask)-1)
2547 
2548 /*
2549 ** The following structure describes the FROM clause of a SELECT statement.
2550 ** Each table or subquery in the FROM clause is a separate element of
2551 ** the SrcList.a[] array.
2552 **
2553 ** With the addition of multiple database support, the following structure
2554 ** can also be used to describe a particular table such as the table that
2555 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
2556 ** such a table must be a simple name: ID.  But in SQLite, the table can
2557 ** now be identified by a database name, a dot, then the table name: ID.ID.
2558 **
2559 ** The jointype starts out showing the join type between the current table
2560 ** and the next table on the list.  The parser builds the list this way.
2561 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
2562 ** jointype expresses the join between the table and the previous table.
2563 **
2564 ** In the colUsed field, the high-order bit (bit 63) is set if the table
2565 ** contains more than 63 columns and the 64-th or later column is used.
2566 */
2567 struct SrcList {
2568   int nSrc;        /* Number of tables or subqueries in the FROM clause */
2569   u32 nAlloc;      /* Number of entries allocated in a[] below */
2570   struct SrcList_item {
2571     Schema *pSchema;  /* Schema to which this item is fixed */
2572     char *zDatabase;  /* Name of database holding this table */
2573     char *zName;      /* Name of the table */
2574     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
2575     Table *pTab;      /* An SQL table corresponding to zName */
2576     Select *pSelect;  /* A SELECT statement used in place of a table name */
2577     int addrFillSub;  /* Address of subroutine to manifest a subquery */
2578     int regReturn;    /* Register holding return address of addrFillSub */
2579     int regResult;    /* Registers holding results of a co-routine */
2580     struct {
2581       u8 jointype;      /* Type of join between this table and the previous */
2582       unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
2583       unsigned isIndexedBy :1;   /* True if there is an INDEXED BY clause */
2584       unsigned isTabFunc :1;     /* True if table-valued-function syntax */
2585       unsigned isCorrelated :1;  /* True if sub-query is correlated */
2586       unsigned viaCoroutine :1;  /* Implemented as a co-routine */
2587       unsigned isRecursive :1;   /* True for recursive reference in WITH */
2588     } fg;
2589 #ifndef SQLITE_OMIT_EXPLAIN
2590     u8 iSelectId;     /* If pSelect!=0, the id of the sub-select in EQP */
2591 #endif
2592     int iCursor;      /* The VDBE cursor number used to access this table */
2593     Expr *pOn;        /* The ON clause of a join */
2594     IdList *pUsing;   /* The USING clause of a join */
2595     Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
2596     union {
2597       char *zIndexedBy;    /* Identifier from "INDEXED BY <zIndex>" clause */
2598       ExprList *pFuncArg;  /* Arguments to table-valued-function */
2599     } u1;
2600     Index *pIBIndex;  /* Index structure corresponding to u1.zIndexedBy */
2601   } a[1];             /* One entry for each identifier on the list */
2602 };
2603 
2604 /*
2605 ** Permitted values of the SrcList.a.jointype field
2606 */
2607 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
2608 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
2609 #define JT_NATURAL   0x0004    /* True for a "natural" join */
2610 #define JT_LEFT      0x0008    /* Left outer join */
2611 #define JT_RIGHT     0x0010    /* Right outer join */
2612 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
2613 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
2614 
2615 
2616 /*
2617 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
2618 ** and the WhereInfo.wctrlFlags member.
2619 **
2620 ** Value constraints (enforced via assert()):
2621 **     WHERE_USE_LIMIT  == SF_FixedLimit
2622 */
2623 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
2624 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
2625 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
2626 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
2627 #define WHERE_ONEPASS_MULTIROW 0x0008 /* ONEPASS is ok with multiple rows */
2628 #define WHERE_DUPLICATES_OK    0x0010 /* Ok to return a row more than once */
2629 #define WHERE_OR_SUBCLAUSE     0x0020 /* Processing a sub-WHERE as part of
2630                                       ** the OR optimization  */
2631 #define WHERE_GROUPBY          0x0040 /* pOrderBy is really a GROUP BY */
2632 #define WHERE_DISTINCTBY       0x0080 /* pOrderby is really a DISTINCT clause */
2633 #define WHERE_WANT_DISTINCT    0x0100 /* All output needs to be distinct */
2634 #define WHERE_SORTBYGROUP      0x0200 /* Support sqlite3WhereIsSorted() */
2635 #define WHERE_SEEK_TABLE       0x0400 /* Do not defer seeks on main table */
2636 #define WHERE_ORDERBY_LIMIT    0x0800 /* ORDERBY+LIMIT on the inner loop */
2637 #define WHERE_SEEK_UNIQ_TABLE  0x1000 /* Do not defer seeks if unique */
2638                         /*     0x2000    not currently used */
2639 #define WHERE_USE_LIMIT        0x4000 /* Use the LIMIT in cost estimates */
2640                         /*     0x8000    not currently used */
2641 
2642 /* Allowed return values from sqlite3WhereIsDistinct()
2643 */
2644 #define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
2645 #define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
2646 #define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
2647 #define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
2648 
2649 /*
2650 ** A NameContext defines a context in which to resolve table and column
2651 ** names.  The context consists of a list of tables (the pSrcList) field and
2652 ** a list of named expression (pEList).  The named expression list may
2653 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
2654 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
2655 ** pEList corresponds to the result set of a SELECT and is NULL for
2656 ** other statements.
2657 **
2658 ** NameContexts can be nested.  When resolving names, the inner-most
2659 ** context is searched first.  If no match is found, the next outer
2660 ** context is checked.  If there is still no match, the next context
2661 ** is checked.  This process continues until either a match is found
2662 ** or all contexts are check.  When a match is found, the nRef member of
2663 ** the context containing the match is incremented.
2664 **
2665 ** Each subquery gets a new NameContext.  The pNext field points to the
2666 ** NameContext in the parent query.  Thus the process of scanning the
2667 ** NameContext list corresponds to searching through successively outer
2668 ** subqueries looking for a match.
2669 */
2670 struct NameContext {
2671   Parse *pParse;       /* The parser */
2672   SrcList *pSrcList;   /* One or more tables used to resolve names */
2673   ExprList *pEList;    /* Optional list of result-set columns */
2674   AggInfo *pAggInfo;   /* Information about aggregates at this level */
2675   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
2676   int nRef;            /* Number of names resolved by this context */
2677   int nErr;            /* Number of errors encountered while resolving names */
2678   u16 ncFlags;         /* Zero or more NC_* flags defined below */
2679 };
2680 
2681 /*
2682 ** Allowed values for the NameContext, ncFlags field.
2683 **
2684 ** Value constraints (all checked via assert()):
2685 **    NC_HasAgg    == SF_HasAgg
2686 **    NC_MinMaxAgg == SF_MinMaxAgg == SQLITE_FUNC_MINMAX
2687 **
2688 */
2689 #define NC_AllowAgg  0x0001  /* Aggregate functions are allowed here */
2690 #define NC_PartIdx   0x0002  /* True if resolving a partial index WHERE */
2691 #define NC_IsCheck   0x0004  /* True if resolving names in a CHECK constraint */
2692 #define NC_InAggFunc 0x0008  /* True if analyzing arguments to an agg func */
2693 #define NC_HasAgg    0x0010  /* One or more aggregate functions seen */
2694 #define NC_IdxExpr   0x0020  /* True if resolving columns of CREATE INDEX */
2695 #define NC_VarSelect 0x0040  /* A correlated subquery has been seen */
2696 #define NC_MinMaxAgg 0x1000  /* min/max aggregates seen.  See note above */
2697 
2698 /*
2699 ** An instance of the following structure contains all information
2700 ** needed to generate code for a single SELECT statement.
2701 **
2702 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
2703 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
2704 ** limit and nOffset to the value of the offset (or 0 if there is not
2705 ** offset).  But later on, nLimit and nOffset become the memory locations
2706 ** in the VDBE that record the limit and offset counters.
2707 **
2708 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
2709 ** These addresses must be stored so that we can go back and fill in
2710 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
2711 ** the number of columns in P2 can be computed at the same time
2712 ** as the OP_OpenEphm instruction is coded because not
2713 ** enough information about the compound query is known at that point.
2714 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
2715 ** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
2716 ** sequences for the ORDER BY clause.
2717 */
2718 struct Select {
2719   ExprList *pEList;      /* The fields of the result */
2720   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
2721   LogEst nSelectRow;     /* Estimated number of result rows */
2722   u32 selFlags;          /* Various SF_* values */
2723   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
2724 #if SELECTTRACE_ENABLED
2725   char zSelName[12];     /* Symbolic name of this SELECT use for debugging */
2726 #endif
2727   int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
2728   SrcList *pSrc;         /* The FROM clause */
2729   Expr *pWhere;          /* The WHERE clause */
2730   ExprList *pGroupBy;    /* The GROUP BY clause */
2731   Expr *pHaving;         /* The HAVING clause */
2732   ExprList *pOrderBy;    /* The ORDER BY clause */
2733   Select *pPrior;        /* Prior select in a compound select statement */
2734   Select *pNext;         /* Next select to the left in a compound */
2735   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
2736   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
2737   With *pWith;           /* WITH clause attached to this select. Or NULL. */
2738 };
2739 
2740 /*
2741 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
2742 ** "Select Flag".
2743 **
2744 ** Value constraints (all checked via assert())
2745 **     SF_HasAgg     == NC_HasAgg
2746 **     SF_MinMaxAgg  == NC_MinMaxAgg     == SQLITE_FUNC_MINMAX
2747 **     SF_FixedLimit == WHERE_USE_LIMIT
2748 */
2749 #define SF_Distinct       0x00001  /* Output should be DISTINCT */
2750 #define SF_All            0x00002  /* Includes the ALL keyword */
2751 #define SF_Resolved       0x00004  /* Identifiers have been resolved */
2752 #define SF_Aggregate      0x00008  /* Contains agg functions or a GROUP BY */
2753 #define SF_HasAgg         0x00010  /* Contains aggregate functions */
2754 #define SF_UsesEphemeral  0x00020  /* Uses the OpenEphemeral opcode */
2755 #define SF_Expanded       0x00040  /* sqlite3SelectExpand() called on this */
2756 #define SF_HasTypeInfo    0x00080  /* FROM subqueries have Table metadata */
2757 #define SF_Compound       0x00100  /* Part of a compound query */
2758 #define SF_Values         0x00200  /* Synthesized from VALUES clause */
2759 #define SF_MultiValue     0x00400  /* Single VALUES term with multiple rows */
2760 #define SF_NestedFrom     0x00800  /* Part of a parenthesized FROM clause */
2761 #define SF_MinMaxAgg      0x01000  /* Aggregate containing min() or max() */
2762 #define SF_Recursive      0x02000  /* The recursive part of a recursive CTE */
2763 #define SF_FixedLimit     0x04000  /* nSelectRow set by a constant LIMIT */
2764 #define SF_MaybeConvert   0x08000  /* Need convertCompoundSelectToSubquery() */
2765 #define SF_Converted      0x10000  /* By convertCompoundSelectToSubquery() */
2766 #define SF_IncludeHidden  0x20000  /* Include hidden columns in output */
2767 
2768 
2769 /*
2770 ** The results of a SELECT can be distributed in several ways, as defined
2771 ** by one of the following macros.  The "SRT" prefix means "SELECT Result
2772 ** Type".
2773 **
2774 **     SRT_Union       Store results as a key in a temporary index
2775 **                     identified by pDest->iSDParm.
2776 **
2777 **     SRT_Except      Remove results from the temporary index pDest->iSDParm.
2778 **
2779 **     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
2780 **                     set is not empty.
2781 **
2782 **     SRT_Discard     Throw the results away.  This is used by SELECT
2783 **                     statements within triggers whose only purpose is
2784 **                     the side-effects of functions.
2785 **
2786 ** All of the above are free to ignore their ORDER BY clause. Those that
2787 ** follow must honor the ORDER BY clause.
2788 **
2789 **     SRT_Output      Generate a row of output (using the OP_ResultRow
2790 **                     opcode) for each row in the result set.
2791 **
2792 **     SRT_Mem         Only valid if the result is a single column.
2793 **                     Store the first column of the first result row
2794 **                     in register pDest->iSDParm then abandon the rest
2795 **                     of the query.  This destination implies "LIMIT 1".
2796 **
2797 **     SRT_Set         The result must be a single column.  Store each
2798 **                     row of result as the key in table pDest->iSDParm.
2799 **                     Apply the affinity pDest->affSdst before storing
2800 **                     results.  Used to implement "IN (SELECT ...)".
2801 **
2802 **     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
2803 **                     the result there. The cursor is left open after
2804 **                     returning.  This is like SRT_Table except that
2805 **                     this destination uses OP_OpenEphemeral to create
2806 **                     the table first.
2807 **
2808 **     SRT_Coroutine   Generate a co-routine that returns a new row of
2809 **                     results each time it is invoked.  The entry point
2810 **                     of the co-routine is stored in register pDest->iSDParm
2811 **                     and the result row is stored in pDest->nDest registers
2812 **                     starting with pDest->iSdst.
2813 **
2814 **     SRT_Table       Store results in temporary table pDest->iSDParm.
2815 **     SRT_Fifo        This is like SRT_EphemTab except that the table
2816 **                     is assumed to already be open.  SRT_Fifo has
2817 **                     the additional property of being able to ignore
2818 **                     the ORDER BY clause.
2819 **
2820 **     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
2821 **                     But also use temporary table pDest->iSDParm+1 as
2822 **                     a record of all prior results and ignore any duplicate
2823 **                     rows.  Name means:  "Distinct Fifo".
2824 **
2825 **     SRT_Queue       Store results in priority queue pDest->iSDParm (really
2826 **                     an index).  Append a sequence number so that all entries
2827 **                     are distinct.
2828 **
2829 **     SRT_DistQueue   Store results in priority queue pDest->iSDParm only if
2830 **                     the same record has never been stored before.  The
2831 **                     index at pDest->iSDParm+1 hold all prior stores.
2832 */
2833 #define SRT_Union        1  /* Store result as keys in an index */
2834 #define SRT_Except       2  /* Remove result from a UNION index */
2835 #define SRT_Exists       3  /* Store 1 if the result is not empty */
2836 #define SRT_Discard      4  /* Do not save the results anywhere */
2837 #define SRT_Fifo         5  /* Store result as data with an automatic rowid */
2838 #define SRT_DistFifo     6  /* Like SRT_Fifo, but unique results only */
2839 #define SRT_Queue        7  /* Store result in an queue */
2840 #define SRT_DistQueue    8  /* Like SRT_Queue, but unique results only */
2841 
2842 /* The ORDER BY clause is ignored for all of the above */
2843 #define IgnorableOrderby(X) ((X->eDest)<=SRT_DistQueue)
2844 
2845 #define SRT_Output       9  /* Output each row of result */
2846 #define SRT_Mem         10  /* Store result in a memory cell */
2847 #define SRT_Set         11  /* Store results as keys in an index */
2848 #define SRT_EphemTab    12  /* Create transient tab and store like SRT_Table */
2849 #define SRT_Coroutine   13  /* Generate a single row of result */
2850 #define SRT_Table       14  /* Store result as data with an automatic rowid */
2851 
2852 /*
2853 ** An instance of this object describes where to put of the results of
2854 ** a SELECT statement.
2855 */
2856 struct SelectDest {
2857   u8 eDest;            /* How to dispose of the results.  On of SRT_* above. */
2858   int iSDParm;         /* A parameter used by the eDest disposal method */
2859   int iSdst;           /* Base register where results are written */
2860   int nSdst;           /* Number of registers allocated */
2861   char *zAffSdst;      /* Affinity used when eDest==SRT_Set */
2862   ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
2863 };
2864 
2865 /*
2866 ** During code generation of statements that do inserts into AUTOINCREMENT
2867 ** tables, the following information is attached to the Table.u.autoInc.p
2868 ** pointer of each autoincrement table to record some side information that
2869 ** the code generator needs.  We have to keep per-table autoincrement
2870 ** information in case inserts are done within triggers.  Triggers do not
2871 ** normally coordinate their activities, but we do need to coordinate the
2872 ** loading and saving of autoincrement information.
2873 */
2874 struct AutoincInfo {
2875   AutoincInfo *pNext;   /* Next info block in a list of them all */
2876   Table *pTab;          /* Table this info block refers to */
2877   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
2878   int regCtr;           /* Memory register holding the rowid counter */
2879 };
2880 
2881 /*
2882 ** Size of the column cache
2883 */
2884 #ifndef SQLITE_N_COLCACHE
2885 # define SQLITE_N_COLCACHE 10
2886 #endif
2887 
2888 /*
2889 ** At least one instance of the following structure is created for each
2890 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
2891 ** statement. All such objects are stored in the linked list headed at
2892 ** Parse.pTriggerPrg and deleted once statement compilation has been
2893 ** completed.
2894 **
2895 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
2896 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
2897 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
2898 ** The Parse.pTriggerPrg list never contains two entries with the same
2899 ** values for both pTrigger and orconf.
2900 **
2901 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
2902 ** accessed (or set to 0 for triggers fired as a result of INSERT
2903 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
2904 ** a mask of new.* columns used by the program.
2905 */
2906 struct TriggerPrg {
2907   Trigger *pTrigger;      /* Trigger this program was coded from */
2908   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
2909   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
2910   int orconf;             /* Default ON CONFLICT policy */
2911   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
2912 };
2913 
2914 /*
2915 ** The yDbMask datatype for the bitmask of all attached databases.
2916 */
2917 #if SQLITE_MAX_ATTACHED>30
2918   typedef unsigned char yDbMask[(SQLITE_MAX_ATTACHED+9)/8];
2919 # define DbMaskTest(M,I)    (((M)[(I)/8]&(1<<((I)&7)))!=0)
2920 # define DbMaskZero(M)      memset((M),0,sizeof(M))
2921 # define DbMaskSet(M,I)     (M)[(I)/8]|=(1<<((I)&7))
2922 # define DbMaskAllZero(M)   sqlite3DbMaskAllZero(M)
2923 # define DbMaskNonZero(M)   (sqlite3DbMaskAllZero(M)==0)
2924 #else
2925   typedef unsigned int yDbMask;
2926 # define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
2927 # define DbMaskZero(M)      (M)=0
2928 # define DbMaskSet(M,I)     (M)|=(((yDbMask)1)<<(I))
2929 # define DbMaskAllZero(M)   (M)==0
2930 # define DbMaskNonZero(M)   (M)!=0
2931 #endif
2932 
2933 /*
2934 ** An SQL parser context.  A copy of this structure is passed through
2935 ** the parser and down into all the parser action routine in order to
2936 ** carry around information that is global to the entire parse.
2937 **
2938 ** The structure is divided into two parts.  When the parser and code
2939 ** generate call themselves recursively, the first part of the structure
2940 ** is constant but the second part is reset at the beginning and end of
2941 ** each recursion.
2942 **
2943 ** The nTableLock and aTableLock variables are only used if the shared-cache
2944 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
2945 ** used to store the set of table-locks required by the statement being
2946 ** compiled. Function sqlite3TableLock() is used to add entries to the
2947 ** list.
2948 */
2949 struct Parse {
2950   sqlite3 *db;         /* The main database structure */
2951   char *zErrMsg;       /* An error message */
2952   Vdbe *pVdbe;         /* An engine for executing database bytecode */
2953   int rc;              /* Return code from execution */
2954   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
2955   u8 checkSchema;      /* Causes schema cookie check after an error */
2956   u8 nested;           /* Number of nested calls to the parser/code generator */
2957   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
2958   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
2959   u8 mayAbort;         /* True if statement may throw an ABORT exception */
2960   u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
2961   u8 okConstFactor;    /* OK to factor out constants */
2962   u8 disableLookaside; /* Number of times lookaside has been disabled */
2963   u8 nColCache;        /* Number of entries in aColCache[] */
2964   int nRangeReg;       /* Size of the temporary register block */
2965   int iRangeReg;       /* First register in temporary register block */
2966   int nErr;            /* Number of errors seen */
2967   int nTab;            /* Number of previously allocated VDBE cursors */
2968   int nMem;            /* Number of memory cells used so far */
2969   int nOpAlloc;        /* Number of slots allocated for Vdbe.aOp[] */
2970   int szOpAlloc;       /* Bytes of memory space allocated for Vdbe.aOp[] */
2971   int iSelfTab;        /* Table for associated with an index on expr, or negative
2972                        ** of the base register during check-constraint eval */
2973   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
2974   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
2975   int nLabel;          /* Number of labels used */
2976   int *aLabel;         /* Space to hold the labels */
2977   ExprList *pConstExpr;/* Constant expressions */
2978   Token constraintName;/* Name of the constraint currently being parsed */
2979   yDbMask writeMask;   /* Start a write transaction on these databases */
2980   yDbMask cookieMask;  /* Bitmask of schema verified databases */
2981   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
2982   int regRoot;         /* Register holding root page number for new objects */
2983   int nMaxArg;         /* Max args passed to user function by sub-program */
2984 #if SELECTTRACE_ENABLED
2985   int nSelect;         /* Number of SELECT statements seen */
2986   int nSelectIndent;   /* How far to indent SELECTTRACE() output */
2987 #endif
2988 #ifndef SQLITE_OMIT_SHARED_CACHE
2989   int nTableLock;        /* Number of locks in aTableLock */
2990   TableLock *aTableLock; /* Required table locks for shared-cache mode */
2991 #endif
2992   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
2993   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
2994   Table *pTriggerTab;  /* Table triggers are being coded for */
2995   int addrCrTab;       /* Address of OP_CreateBtree opcode on CREATE TABLE */
2996   u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
2997   u32 oldmask;         /* Mask of old.* columns referenced */
2998   u32 newmask;         /* Mask of new.* columns referenced */
2999   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
3000   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
3001   u8 disableTriggers;  /* True to disable triggers */
3002 
3003   /**************************************************************************
3004   ** Fields above must be initialized to zero.  The fields that follow,
3005   ** down to the beginning of the recursive section, do not need to be
3006   ** initialized as they will be set before being used.  The boundary is
3007   ** determined by offsetof(Parse,aColCache).
3008   **************************************************************************/
3009 
3010   struct yColCache {
3011     int iTable;           /* Table cursor number */
3012     i16 iColumn;          /* Table column number */
3013     u8 tempReg;           /* iReg is a temp register that needs to be freed */
3014     int iLevel;           /* Nesting level */
3015     int iReg;             /* Reg with value of this column. 0 means none. */
3016     int lru;              /* Least recently used entry has the smallest value */
3017   } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
3018   int aTempReg[8];        /* Holding area for temporary registers */
3019   Token sNameToken;       /* Token with unqualified schema object name */
3020 
3021   /************************************************************************
3022   ** Above is constant between recursions.  Below is reset before and after
3023   ** each recursion.  The boundary between these two regions is determined
3024   ** using offsetof(Parse,sLastToken) so the sLastToken field must be the
3025   ** first field in the recursive region.
3026   ************************************************************************/
3027 
3028   Token sLastToken;       /* The last token parsed */
3029   ynVar nVar;               /* Number of '?' variables seen in the SQL so far */
3030   u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
3031   u8 explain;               /* True if the EXPLAIN flag is found on the query */
3032 #ifndef SQLITE_OMIT_VIRTUALTABLE
3033   u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
3034   int nVtabLock;            /* Number of virtual tables to lock */
3035 #endif
3036   int nHeight;              /* Expression tree height of current sub-select */
3037 #ifndef SQLITE_OMIT_EXPLAIN
3038   int iSelectId;            /* ID of current select for EXPLAIN output */
3039   int iNextSelectId;        /* Next available select ID for EXPLAIN output */
3040 #endif
3041   VList *pVList;            /* Mapping between variable names and numbers */
3042   Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
3043   const char *zTail;        /* All SQL text past the last semicolon parsed */
3044   Table *pNewTable;         /* A table being constructed by CREATE TABLE */
3045   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
3046   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
3047 #ifndef SQLITE_OMIT_VIRTUALTABLE
3048   Token sArg;               /* Complete text of a module argument */
3049   Table **apVtabLock;       /* Pointer to virtual tables needing locking */
3050 #endif
3051   Table *pZombieTab;        /* List of Table objects to delete after code gen */
3052   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
3053   With *pWith;              /* Current WITH clause, or NULL */
3054   With *pWithToFree;        /* Free this WITH object at the end of the parse */
3055 };
3056 
3057 /*
3058 ** Sizes and pointers of various parts of the Parse object.
3059 */
3060 #define PARSE_HDR_SZ offsetof(Parse,aColCache) /* Recursive part w/o aColCache*/
3061 #define PARSE_RECURSE_SZ offsetof(Parse,sLastToken)    /* Recursive part */
3062 #define PARSE_TAIL_SZ (sizeof(Parse)-PARSE_RECURSE_SZ) /* Non-recursive part */
3063 #define PARSE_TAIL(X) (((char*)(X))+PARSE_RECURSE_SZ)  /* Pointer to tail */
3064 
3065 /*
3066 ** Return true if currently inside an sqlite3_declare_vtab() call.
3067 */
3068 #ifdef SQLITE_OMIT_VIRTUALTABLE
3069   #define IN_DECLARE_VTAB 0
3070 #else
3071   #define IN_DECLARE_VTAB (pParse->declareVtab)
3072 #endif
3073 
3074 /*
3075 ** An instance of the following structure can be declared on a stack and used
3076 ** to save the Parse.zAuthContext value so that it can be restored later.
3077 */
3078 struct AuthContext {
3079   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
3080   Parse *pParse;              /* The Parse structure */
3081 };
3082 
3083 /*
3084 ** Bitfield flags for P5 value in various opcodes.
3085 **
3086 ** Value constraints (enforced via assert()):
3087 **    OPFLAG_LENGTHARG    == SQLITE_FUNC_LENGTH
3088 **    OPFLAG_TYPEOFARG    == SQLITE_FUNC_TYPEOF
3089 **    OPFLAG_BULKCSR      == BTREE_BULKLOAD
3090 **    OPFLAG_SEEKEQ       == BTREE_SEEK_EQ
3091 **    OPFLAG_FORDELETE    == BTREE_FORDELETE
3092 **    OPFLAG_SAVEPOSITION == BTREE_SAVEPOSITION
3093 **    OPFLAG_AUXDELETE    == BTREE_AUXDELETE
3094 */
3095 #define OPFLAG_NCHANGE       0x01    /* OP_Insert: Set to update db->nChange */
3096                                      /* Also used in P2 (not P5) of OP_Delete */
3097 #define OPFLAG_EPHEM         0x01    /* OP_Column: Ephemeral output is ok */
3098 #define OPFLAG_LASTROWID     0x20    /* Set to update db->lastRowid */
3099 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
3100 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
3101 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
3102 #define OPFLAG_ISNOOP        0x40    /* OP_Delete does pre-update-hook only */
3103 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
3104 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
3105 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
3106 #define OPFLAG_SEEKEQ        0x02    /* OP_Open** cursor uses EQ seek only */
3107 #define OPFLAG_FORDELETE     0x08    /* OP_Open should use BTREE_FORDELETE */
3108 #define OPFLAG_P2ISREG       0x10    /* P2 to OP_Open** is a register number */
3109 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
3110 #define OPFLAG_SAVEPOSITION  0x02    /* OP_Delete/Insert: save cursor pos */
3111 #define OPFLAG_AUXDELETE     0x04    /* OP_Delete: index in a DELETE op */
3112 
3113 /*
3114  * Each trigger present in the database schema is stored as an instance of
3115  * struct Trigger.
3116  *
3117  * Pointers to instances of struct Trigger are stored in two ways.
3118  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
3119  *    database). This allows Trigger structures to be retrieved by name.
3120  * 2. All triggers associated with a single table form a linked list, using the
3121  *    pNext member of struct Trigger. A pointer to the first element of the
3122  *    linked list is stored as the "pTrigger" member of the associated
3123  *    struct Table.
3124  *
3125  * The "step_list" member points to the first element of a linked list
3126  * containing the SQL statements specified as the trigger program.
3127  */
3128 struct Trigger {
3129   char *zName;            /* The name of the trigger                        */
3130   char *table;            /* The table or view to which the trigger applies */
3131   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
3132   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
3133   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
3134   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
3135                              the <column-list> is stored here */
3136   Schema *pSchema;        /* Schema containing the trigger */
3137   Schema *pTabSchema;     /* Schema containing the table */
3138   TriggerStep *step_list; /* Link list of trigger program steps             */
3139   Trigger *pNext;         /* Next trigger associated with the table */
3140 };
3141 
3142 /*
3143 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
3144 ** determine which.
3145 **
3146 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
3147 ** In that cases, the constants below can be ORed together.
3148 */
3149 #define TRIGGER_BEFORE  1
3150 #define TRIGGER_AFTER   2
3151 
3152 /*
3153  * An instance of struct TriggerStep is used to store a single SQL statement
3154  * that is a part of a trigger-program.
3155  *
3156  * Instances of struct TriggerStep are stored in a singly linked list (linked
3157  * using the "pNext" member) referenced by the "step_list" member of the
3158  * associated struct Trigger instance. The first element of the linked list is
3159  * the first step of the trigger-program.
3160  *
3161  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
3162  * "SELECT" statement. The meanings of the other members is determined by the
3163  * value of "op" as follows:
3164  *
3165  * (op == TK_INSERT)
3166  * orconf    -> stores the ON CONFLICT algorithm
3167  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
3168  *              this stores a pointer to the SELECT statement. Otherwise NULL.
3169  * zTarget   -> Dequoted name of the table to insert into.
3170  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
3171  *              this stores values to be inserted. Otherwise NULL.
3172  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
3173  *              statement, then this stores the column-names to be
3174  *              inserted into.
3175  *
3176  * (op == TK_DELETE)
3177  * zTarget   -> Dequoted name of the table to delete from.
3178  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
3179  *              Otherwise NULL.
3180  *
3181  * (op == TK_UPDATE)
3182  * zTarget   -> Dequoted name of the table to update.
3183  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
3184  *              Otherwise NULL.
3185  * pExprList -> A list of the columns to update and the expressions to update
3186  *              them to. See sqlite3Update() documentation of "pChanges"
3187  *              argument.
3188  *
3189  */
3190 struct TriggerStep {
3191   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
3192   u8 orconf;           /* OE_Rollback etc. */
3193   Trigger *pTrig;      /* The trigger that this step is a part of */
3194   Select *pSelect;     /* SELECT statement or RHS of INSERT INTO SELECT ... */
3195   char *zTarget;       /* Target table for DELETE, UPDATE, INSERT */
3196   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
3197   ExprList *pExprList; /* SET clause for UPDATE. */
3198   IdList *pIdList;     /* Column names for INSERT */
3199   TriggerStep *pNext;  /* Next in the link-list */
3200   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
3201 };
3202 
3203 /*
3204 ** The following structure contains information used by the sqliteFix...
3205 ** routines as they walk the parse tree to make database references
3206 ** explicit.
3207 */
3208 typedef struct DbFixer DbFixer;
3209 struct DbFixer {
3210   Parse *pParse;      /* The parsing context.  Error messages written here */
3211   Schema *pSchema;    /* Fix items to this schema */
3212   int bVarOnly;       /* Check for variable references only */
3213   const char *zDb;    /* Make sure all objects are contained in this database */
3214   const char *zType;  /* Type of the container - used for error messages */
3215   const Token *pName; /* Name of the container - used for error messages */
3216 };
3217 
3218 /*
3219 ** An objected used to accumulate the text of a string where we
3220 ** do not necessarily know how big the string will be in the end.
3221 */
3222 struct StrAccum {
3223   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
3224   char *zText;         /* The string collected so far */
3225   u32  nAlloc;         /* Amount of space allocated in zText */
3226   u32  mxAlloc;        /* Maximum allowed allocation.  0 for no malloc usage */
3227   u32  nChar;          /* Length of the string so far */
3228   u8   accError;       /* STRACCUM_NOMEM or STRACCUM_TOOBIG */
3229   u8   printfFlags;    /* SQLITE_PRINTF flags below */
3230 };
3231 #define STRACCUM_NOMEM   1
3232 #define STRACCUM_TOOBIG  2
3233 #define SQLITE_PRINTF_INTERNAL 0x01  /* Internal-use-only converters allowed */
3234 #define SQLITE_PRINTF_SQLFUNC  0x02  /* SQL function arguments to VXPrintf */
3235 #define SQLITE_PRINTF_MALLOCED 0x04  /* True if xText is allocated space */
3236 
3237 #define isMalloced(X)  (((X)->printfFlags & SQLITE_PRINTF_MALLOCED)!=0)
3238 
3239 
3240 /*
3241 ** A pointer to this structure is used to communicate information
3242 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
3243 */
3244 typedef struct {
3245   sqlite3 *db;        /* The database being initialized */
3246   char **pzErrMsg;    /* Error message stored here */
3247   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
3248   int rc;             /* Result code stored here */
3249 } InitData;
3250 
3251 /*
3252 ** Structure containing global configuration data for the SQLite library.
3253 **
3254 ** This structure also contains some state information.
3255 */
3256 struct Sqlite3Config {
3257   int bMemstat;                     /* True to enable memory status */
3258   int bCoreMutex;                   /* True to enable core mutexing */
3259   int bFullMutex;                   /* True to enable full mutexing */
3260   int bOpenUri;                     /* True to interpret filenames as URIs */
3261   int bUseCis;                      /* Use covering indices for full-scans */
3262   int bSmallMalloc;                 /* Avoid large memory allocations if true */
3263   int mxStrlen;                     /* Maximum string length */
3264   int neverCorrupt;                 /* Database is always well-formed */
3265   int szLookaside;                  /* Default lookaside buffer size */
3266   int nLookaside;                   /* Default lookaside buffer count */
3267   int nStmtSpill;                   /* Stmt-journal spill-to-disk threshold */
3268   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
3269   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
3270   sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
3271   void *pHeap;                      /* Heap storage space */
3272   int nHeap;                        /* Size of pHeap[] */
3273   int mnReq, mxReq;                 /* Min and max heap requests sizes */
3274   sqlite3_int64 szMmap;             /* mmap() space per open file */
3275   sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
3276   void *pPage;                      /* Page cache memory */
3277   int szPage;                       /* Size of each page in pPage[] */
3278   int nPage;                        /* Number of pages in pPage[] */
3279   int mxParserStack;                /* maximum depth of the parser stack */
3280   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
3281   u32 szPma;                        /* Maximum Sorter PMA size */
3282   /* The above might be initialized to non-zero.  The following need to always
3283   ** initially be zero, however. */
3284   int isInit;                       /* True after initialization has finished */
3285   int inProgress;                   /* True while initialization in progress */
3286   int isMutexInit;                  /* True after mutexes are initialized */
3287   int isMallocInit;                 /* True after malloc is initialized */
3288   int isPCacheInit;                 /* True after malloc is initialized */
3289   int nRefInitMutex;                /* Number of users of pInitMutex */
3290   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
3291   void (*xLog)(void*,int,const char*); /* Function for logging */
3292   void *pLogArg;                       /* First argument to xLog() */
3293 #ifdef SQLITE_ENABLE_SQLLOG
3294   void(*xSqllog)(void*,sqlite3*,const char*, int);
3295   void *pSqllogArg;
3296 #endif
3297 #ifdef SQLITE_VDBE_COVERAGE
3298   /* The following callback (if not NULL) is invoked on every VDBE branch
3299   ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
3300   */
3301   void (*xVdbeBranch)(void*,int iSrcLine,u8 eThis,u8 eMx);  /* Callback */
3302   void *pVdbeBranchArg;                                     /* 1st argument */
3303 #endif
3304 #ifndef SQLITE_UNTESTABLE
3305   int (*xTestCallback)(int);        /* Invoked by sqlite3FaultSim() */
3306 #endif
3307   int bLocaltimeFault;              /* True to fail localtime() calls */
3308   int iOnceResetThreshold;          /* When to reset OP_Once counters */
3309 };
3310 
3311 /*
3312 ** This macro is used inside of assert() statements to indicate that
3313 ** the assert is only valid on a well-formed database.  Instead of:
3314 **
3315 **     assert( X );
3316 **
3317 ** One writes:
3318 **
3319 **     assert( X || CORRUPT_DB );
3320 **
3321 ** CORRUPT_DB is true during normal operation.  CORRUPT_DB does not indicate
3322 ** that the database is definitely corrupt, only that it might be corrupt.
3323 ** For most test cases, CORRUPT_DB is set to false using a special
3324 ** sqlite3_test_control().  This enables assert() statements to prove
3325 ** things that are always true for well-formed databases.
3326 */
3327 #define CORRUPT_DB  (sqlite3Config.neverCorrupt==0)
3328 
3329 /*
3330 ** Context pointer passed down through the tree-walk.
3331 */
3332 struct Walker {
3333   Parse *pParse;                            /* Parser context.  */
3334   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
3335   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
3336   void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
3337   int walkerDepth;                          /* Number of subqueries */
3338   u8 eCode;                                 /* A small processing code */
3339   union {                                   /* Extra data for callback */
3340     NameContext *pNC;                         /* Naming context */
3341     int n;                                    /* A counter */
3342     int iCur;                                 /* A cursor number */
3343     SrcList *pSrcList;                        /* FROM clause */
3344     struct SrcCount *pSrcCount;               /* Counting column references */
3345     struct CCurHint *pCCurHint;               /* Used by codeCursorHint() */
3346     int *aiCol;                               /* array of column indexes */
3347     struct IdxCover *pIdxCover;               /* Check for index coverage */
3348     struct IdxExprTrans *pIdxTrans;           /* Convert indexed expr to column */
3349     ExprList *pGroupBy;                       /* GROUP BY clause */
3350     struct HavingToWhereCtx *pHavingCtx;      /* HAVING to WHERE clause ctx */
3351   } u;
3352 };
3353 
3354 /* Forward declarations */
3355 int sqlite3WalkExpr(Walker*, Expr*);
3356 int sqlite3WalkExprList(Walker*, ExprList*);
3357 int sqlite3WalkSelect(Walker*, Select*);
3358 int sqlite3WalkSelectExpr(Walker*, Select*);
3359 int sqlite3WalkSelectFrom(Walker*, Select*);
3360 int sqlite3ExprWalkNoop(Walker*, Expr*);
3361 int sqlite3SelectWalkNoop(Walker*, Select*);
3362 int sqlite3SelectWalkFail(Walker*, Select*);
3363 #ifdef SQLITE_DEBUG
3364 void sqlite3SelectWalkAssert2(Walker*, Select*);
3365 #endif
3366 
3367 /*
3368 ** Return code from the parse-tree walking primitives and their
3369 ** callbacks.
3370 */
3371 #define WRC_Continue    0   /* Continue down into children */
3372 #define WRC_Prune       1   /* Omit children but continue walking siblings */
3373 #define WRC_Abort       2   /* Abandon the tree walk */
3374 
3375 /*
3376 ** An instance of this structure represents a set of one or more CTEs
3377 ** (common table expressions) created by a single WITH clause.
3378 */
3379 struct With {
3380   int nCte;                       /* Number of CTEs in the WITH clause */
3381   With *pOuter;                   /* Containing WITH clause, or NULL */
3382   struct Cte {                    /* For each CTE in the WITH clause.... */
3383     char *zName;                    /* Name of this CTE */
3384     ExprList *pCols;                /* List of explicit column names, or NULL */
3385     Select *pSelect;                /* The definition of this CTE */
3386     const char *zCteErr;            /* Error message for circular references */
3387   } a[1];
3388 };
3389 
3390 #ifdef SQLITE_DEBUG
3391 /*
3392 ** An instance of the TreeView object is used for printing the content of
3393 ** data structures on sqlite3DebugPrintf() using a tree-like view.
3394 */
3395 struct TreeView {
3396   int iLevel;             /* Which level of the tree we are on */
3397   u8  bLine[100];         /* Draw vertical in column i if bLine[i] is true */
3398 };
3399 #endif /* SQLITE_DEBUG */
3400 
3401 /*
3402 ** Assuming zIn points to the first byte of a UTF-8 character,
3403 ** advance zIn to point to the first byte of the next UTF-8 character.
3404 */
3405 #define SQLITE_SKIP_UTF8(zIn) {                        \
3406   if( (*(zIn++))>=0xc0 ){                              \
3407     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
3408   }                                                    \
3409 }
3410 
3411 /*
3412 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
3413 ** the same name but without the _BKPT suffix.  These macros invoke
3414 ** routines that report the line-number on which the error originated
3415 ** using sqlite3_log().  The routines also provide a convenient place
3416 ** to set a debugger breakpoint.
3417 */
3418 int sqlite3CorruptError(int);
3419 int sqlite3MisuseError(int);
3420 int sqlite3CantopenError(int);
3421 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
3422 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
3423 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
3424 #ifdef SQLITE_DEBUG
3425   int sqlite3NomemError(int);
3426   int sqlite3IoerrnomemError(int);
3427   int sqlite3CorruptPgnoError(int,Pgno);
3428 # define SQLITE_NOMEM_BKPT sqlite3NomemError(__LINE__)
3429 # define SQLITE_IOERR_NOMEM_BKPT sqlite3IoerrnomemError(__LINE__)
3430 # define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptPgnoError(__LINE__,(P))
3431 #else
3432 # define SQLITE_NOMEM_BKPT SQLITE_NOMEM
3433 # define SQLITE_IOERR_NOMEM_BKPT SQLITE_IOERR_NOMEM
3434 # define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptError(__LINE__)
3435 #endif
3436 
3437 /*
3438 ** FTS3 and FTS4 both require virtual table support
3439 */
3440 #if defined(SQLITE_OMIT_VIRTUALTABLE)
3441 # undef SQLITE_ENABLE_FTS3
3442 # undef SQLITE_ENABLE_FTS4
3443 #endif
3444 
3445 /*
3446 ** FTS4 is really an extension for FTS3.  It is enabled using the
3447 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also call
3448 ** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
3449 */
3450 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
3451 # define SQLITE_ENABLE_FTS3 1
3452 #endif
3453 
3454 /*
3455 ** The ctype.h header is needed for non-ASCII systems.  It is also
3456 ** needed by FTS3 when FTS3 is included in the amalgamation.
3457 */
3458 #if !defined(SQLITE_ASCII) || \
3459     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
3460 # include <ctype.h>
3461 #endif
3462 
3463 /*
3464 ** The following macros mimic the standard library functions toupper(),
3465 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
3466 ** sqlite versions only work for ASCII characters, regardless of locale.
3467 */
3468 #ifdef SQLITE_ASCII
3469 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
3470 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
3471 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
3472 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
3473 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
3474 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
3475 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
3476 # define sqlite3Isquote(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x80)
3477 #else
3478 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
3479 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
3480 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
3481 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
3482 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
3483 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
3484 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
3485 # define sqlite3Isquote(x)   ((x)=='"'||(x)=='\''||(x)=='['||(x)=='`')
3486 #endif
3487 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
3488 int sqlite3IsIdChar(u8);
3489 #endif
3490 
3491 /*
3492 ** Internal function prototypes
3493 */
3494 int sqlite3StrICmp(const char*,const char*);
3495 int sqlite3Strlen30(const char*);
3496 char *sqlite3ColumnType(Column*,char*);
3497 #define sqlite3StrNICmp sqlite3_strnicmp
3498 
3499 int sqlite3MallocInit(void);
3500 void sqlite3MallocEnd(void);
3501 void *sqlite3Malloc(u64);
3502 void *sqlite3MallocZero(u64);
3503 void *sqlite3DbMallocZero(sqlite3*, u64);
3504 void *sqlite3DbMallocRaw(sqlite3*, u64);
3505 void *sqlite3DbMallocRawNN(sqlite3*, u64);
3506 char *sqlite3DbStrDup(sqlite3*,const char*);
3507 char *sqlite3DbStrNDup(sqlite3*,const char*, u64);
3508 void *sqlite3Realloc(void*, u64);
3509 void *sqlite3DbReallocOrFree(sqlite3 *, void *, u64);
3510 void *sqlite3DbRealloc(sqlite3 *, void *, u64);
3511 void sqlite3DbFree(sqlite3*, void*);
3512 void sqlite3DbFreeNN(sqlite3*, void*);
3513 int sqlite3MallocSize(void*);
3514 int sqlite3DbMallocSize(sqlite3*, void*);
3515 void *sqlite3PageMalloc(int);
3516 void sqlite3PageFree(void*);
3517 void sqlite3MemSetDefault(void);
3518 #ifndef SQLITE_UNTESTABLE
3519 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
3520 #endif
3521 int sqlite3HeapNearlyFull(void);
3522 
3523 /*
3524 ** On systems with ample stack space and that support alloca(), make
3525 ** use of alloca() to obtain space for large automatic objects.  By default,
3526 ** obtain space from malloc().
3527 **
3528 ** The alloca() routine never returns NULL.  This will cause code paths
3529 ** that deal with sqlite3StackAlloc() failures to be unreachable.
3530 */
3531 #ifdef SQLITE_USE_ALLOCA
3532 # define sqlite3StackAllocRaw(D,N)   alloca(N)
3533 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
3534 # define sqlite3StackFree(D,P)
3535 #else
3536 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
3537 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
3538 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
3539 #endif
3540 
3541 /* Do not allow both MEMSYS5 and MEMSYS3 to be defined together.  If they
3542 ** are, disable MEMSYS3
3543 */
3544 #ifdef SQLITE_ENABLE_MEMSYS5
3545 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
3546 #undef SQLITE_ENABLE_MEMSYS3
3547 #endif
3548 #ifdef SQLITE_ENABLE_MEMSYS3
3549 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
3550 #endif
3551 
3552 
3553 #ifndef SQLITE_MUTEX_OMIT
3554   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
3555   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
3556   sqlite3_mutex *sqlite3MutexAlloc(int);
3557   int sqlite3MutexInit(void);
3558   int sqlite3MutexEnd(void);
3559 #endif
3560 #if !defined(SQLITE_MUTEX_OMIT) && !defined(SQLITE_MUTEX_NOOP)
3561   void sqlite3MemoryBarrier(void);
3562 #else
3563 # define sqlite3MemoryBarrier()
3564 #endif
3565 
3566 sqlite3_int64 sqlite3StatusValue(int);
3567 void sqlite3StatusUp(int, int);
3568 void sqlite3StatusDown(int, int);
3569 void sqlite3StatusHighwater(int, int);
3570 int sqlite3LookasideUsed(sqlite3*,int*);
3571 
3572 /* Access to mutexes used by sqlite3_status() */
3573 sqlite3_mutex *sqlite3Pcache1Mutex(void);
3574 sqlite3_mutex *sqlite3MallocMutex(void);
3575 
3576 #ifndef SQLITE_OMIT_FLOATING_POINT
3577   int sqlite3IsNaN(double);
3578 #else
3579 # define sqlite3IsNaN(X)  0
3580 #endif
3581 
3582 /*
3583 ** An instance of the following structure holds information about SQL
3584 ** functions arguments that are the parameters to the printf() function.
3585 */
3586 struct PrintfArguments {
3587   int nArg;                /* Total number of arguments */
3588   int nUsed;               /* Number of arguments used so far */
3589   sqlite3_value **apArg;   /* The argument values */
3590 };
3591 
3592 void sqlite3VXPrintf(StrAccum*, const char*, va_list);
3593 void sqlite3XPrintf(StrAccum*, const char*, ...);
3594 char *sqlite3MPrintf(sqlite3*,const char*, ...);
3595 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
3596 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
3597   void sqlite3DebugPrintf(const char*, ...);
3598 #endif
3599 #if defined(SQLITE_TEST)
3600   void *sqlite3TestTextToPtr(const char*);
3601 #endif
3602 
3603 #if defined(SQLITE_DEBUG)
3604   void sqlite3TreeViewExpr(TreeView*, const Expr*, u8);
3605   void sqlite3TreeViewBareExprList(TreeView*, const ExprList*, const char*);
3606   void sqlite3TreeViewExprList(TreeView*, const ExprList*, u8, const char*);
3607   void sqlite3TreeViewSelect(TreeView*, const Select*, u8);
3608   void sqlite3TreeViewWith(TreeView*, const With*, u8);
3609 #endif
3610 
3611 
3612 void sqlite3SetString(char **, sqlite3*, const char*);
3613 void sqlite3ErrorMsg(Parse*, const char*, ...);
3614 void sqlite3Dequote(char*);
3615 void sqlite3TokenInit(Token*,char*);
3616 int sqlite3KeywordCode(const unsigned char*, int);
3617 int sqlite3RunParser(Parse*, const char*, char **);
3618 void sqlite3FinishCoding(Parse*);
3619 int sqlite3GetTempReg(Parse*);
3620 void sqlite3ReleaseTempReg(Parse*,int);
3621 int sqlite3GetTempRange(Parse*,int);
3622 void sqlite3ReleaseTempRange(Parse*,int,int);
3623 void sqlite3ClearTempRegCache(Parse*);
3624 #ifdef SQLITE_DEBUG
3625 int sqlite3NoTempsInRange(Parse*,int,int);
3626 #endif
3627 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
3628 Expr *sqlite3Expr(sqlite3*,int,const char*);
3629 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
3630 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*);
3631 void sqlite3PExprAddSelect(Parse*, Expr*, Select*);
3632 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
3633 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
3634 void sqlite3ExprAssignVarNumber(Parse*, Expr*, u32);
3635 void sqlite3ExprDelete(sqlite3*, Expr*);
3636 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
3637 ExprList *sqlite3ExprListAppendVector(Parse*,ExprList*,IdList*,Expr*);
3638 void sqlite3ExprListSetSortOrder(ExprList*,int);
3639 void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
3640 void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
3641 void sqlite3ExprListDelete(sqlite3*, ExprList*);
3642 u32 sqlite3ExprListFlags(const ExprList*);
3643 int sqlite3Init(sqlite3*, char**);
3644 int sqlite3InitCallback(void*, int, char**, char**);
3645 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
3646 #ifndef SQLITE_OMIT_VIRTUALTABLE
3647 Module *sqlite3PragmaVtabRegister(sqlite3*,const char *zName);
3648 #endif
3649 void sqlite3ResetAllSchemasOfConnection(sqlite3*);
3650 void sqlite3ResetOneSchema(sqlite3*,int);
3651 void sqlite3CollapseDatabaseArray(sqlite3*);
3652 void sqlite3CommitInternalChanges(sqlite3*);
3653 void sqlite3DeleteColumnNames(sqlite3*,Table*);
3654 int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
3655 void sqlite3SelectAddColumnTypeAndCollation(Parse*,Table*,Select*);
3656 Table *sqlite3ResultSetOfSelect(Parse*,Select*);
3657 void sqlite3OpenMasterTable(Parse *, int);
3658 Index *sqlite3PrimaryKeyIndex(Table*);
3659 i16 sqlite3ColumnOfIndex(Index*, i16);
3660 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
3661 #if SQLITE_ENABLE_HIDDEN_COLUMNS
3662   void sqlite3ColumnPropertiesFromName(Table*, Column*);
3663 #else
3664 # define sqlite3ColumnPropertiesFromName(T,C) /* no-op */
3665 #endif
3666 void sqlite3AddColumn(Parse*,Token*,Token*);
3667 void sqlite3AddNotNull(Parse*, int);
3668 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
3669 void sqlite3AddCheckConstraint(Parse*, Expr*);
3670 void sqlite3AddDefaultValue(Parse*,ExprSpan*);
3671 void sqlite3AddCollateType(Parse*, Token*);
3672 void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
3673 int sqlite3ParseUri(const char*,const char*,unsigned int*,
3674                     sqlite3_vfs**,char**,char **);
3675 Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
3676 
3677 #ifdef SQLITE_UNTESTABLE
3678 # define sqlite3FaultSim(X) SQLITE_OK
3679 #else
3680   int sqlite3FaultSim(int);
3681 #endif
3682 
3683 Bitvec *sqlite3BitvecCreate(u32);
3684 int sqlite3BitvecTest(Bitvec*, u32);
3685 int sqlite3BitvecTestNotNull(Bitvec*, u32);
3686 int sqlite3BitvecSet(Bitvec*, u32);
3687 void sqlite3BitvecClear(Bitvec*, u32, void*);
3688 void sqlite3BitvecDestroy(Bitvec*);
3689 u32 sqlite3BitvecSize(Bitvec*);
3690 #ifndef SQLITE_UNTESTABLE
3691 int sqlite3BitvecBuiltinTest(int,int*);
3692 #endif
3693 
3694 RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
3695 void sqlite3RowSetClear(RowSet*);
3696 void sqlite3RowSetInsert(RowSet*, i64);
3697 int sqlite3RowSetTest(RowSet*, int iBatch, i64);
3698 int sqlite3RowSetNext(RowSet*, i64*);
3699 
3700 void sqlite3CreateView(Parse*,Token*,Token*,Token*,ExprList*,Select*,int,int);
3701 
3702 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
3703   int sqlite3ViewGetColumnNames(Parse*,Table*);
3704 #else
3705 # define sqlite3ViewGetColumnNames(A,B) 0
3706 #endif
3707 
3708 #if SQLITE_MAX_ATTACHED>30
3709   int sqlite3DbMaskAllZero(yDbMask);
3710 #endif
3711 void sqlite3DropTable(Parse*, SrcList*, int, int);
3712 void sqlite3CodeDropTable(Parse*, Table*, int, int);
3713 void sqlite3DeleteTable(sqlite3*, Table*);
3714 #ifndef SQLITE_OMIT_AUTOINCREMENT
3715   void sqlite3AutoincrementBegin(Parse *pParse);
3716   void sqlite3AutoincrementEnd(Parse *pParse);
3717 #else
3718 # define sqlite3AutoincrementBegin(X)
3719 # define sqlite3AutoincrementEnd(X)
3720 #endif
3721 void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int);
3722 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
3723 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
3724 int sqlite3IdListIndex(IdList*,const char*);
3725 SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
3726 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
3727 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
3728                                       Token*, Select*, Expr*, IdList*);
3729 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
3730 void sqlite3SrcListFuncArgs(Parse*, SrcList*, ExprList*);
3731 int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
3732 void sqlite3SrcListShiftJoinType(SrcList*);
3733 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
3734 void sqlite3IdListDelete(sqlite3*, IdList*);
3735 void sqlite3SrcListDelete(sqlite3*, SrcList*);
3736 Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
3737 void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
3738                           Expr*, int, int, u8);
3739 void sqlite3DropIndex(Parse*, SrcList*, int);
3740 int sqlite3Select(Parse*, Select*, SelectDest*);
3741 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
3742                          Expr*,ExprList*,u32,Expr*,Expr*);
3743 void sqlite3SelectDelete(sqlite3*, Select*);
3744 Table *sqlite3SrcListLookup(Parse*, SrcList*);
3745 int sqlite3IsReadOnly(Parse*, Table*, int);
3746 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
3747 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
3748 Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,Expr*,char*);
3749 #endif
3750 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
3751 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
3752 WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
3753 void sqlite3WhereEnd(WhereInfo*);
3754 LogEst sqlite3WhereOutputRowCount(WhereInfo*);
3755 int sqlite3WhereIsDistinct(WhereInfo*);
3756 int sqlite3WhereIsOrdered(WhereInfo*);
3757 int sqlite3WhereOrderedInnerLoop(WhereInfo*);
3758 int sqlite3WhereIsSorted(WhereInfo*);
3759 int sqlite3WhereContinueLabel(WhereInfo*);
3760 int sqlite3WhereBreakLabel(WhereInfo*);
3761 int sqlite3WhereOkOnePass(WhereInfo*, int*);
3762 #define ONEPASS_OFF      0        /* Use of ONEPASS not allowed */
3763 #define ONEPASS_SINGLE   1        /* ONEPASS valid for a single row update */
3764 #define ONEPASS_MULTI    2        /* ONEPASS is valid for multiple rows */
3765 void sqlite3ExprCodeLoadIndexColumn(Parse*, Index*, int, int, int);
3766 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
3767 void sqlite3ExprCodeGetColumnToReg(Parse*, Table*, int, int, int);
3768 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
3769 void sqlite3ExprCodeMove(Parse*, int, int, int);
3770 void sqlite3ExprCacheStore(Parse*, int, int, int);
3771 void sqlite3ExprCachePush(Parse*);
3772 void sqlite3ExprCachePop(Parse*);
3773 void sqlite3ExprCacheRemove(Parse*, int, int);
3774 void sqlite3ExprCacheClear(Parse*);
3775 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
3776 void sqlite3ExprCode(Parse*, Expr*, int);
3777 void sqlite3ExprCodeCopy(Parse*, Expr*, int);
3778 void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
3779 int sqlite3ExprCodeAtInit(Parse*, Expr*, int);
3780 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
3781 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
3782 void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
3783 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int, u8);
3784 #define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
3785 #define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
3786 #define SQLITE_ECEL_REF      0x04  /* Use ExprList.u.x.iOrderByCol */
3787 #define SQLITE_ECEL_OMITREF  0x08  /* Omit if ExprList.u.x.iOrderByCol */
3788 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
3789 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
3790 void sqlite3ExprIfFalseDup(Parse*, Expr*, int, int);
3791 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
3792 #define LOCATE_VIEW    0x01
3793 #define LOCATE_NOERR   0x02
3794 Table *sqlite3LocateTable(Parse*,u32 flags,const char*, const char*);
3795 Table *sqlite3LocateTableItem(Parse*,u32 flags,struct SrcList_item *);
3796 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
3797 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
3798 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
3799 void sqlite3Vacuum(Parse*,Token*);
3800 int sqlite3RunVacuum(char**, sqlite3*, int);
3801 char *sqlite3NameFromToken(sqlite3*, Token*);
3802 int sqlite3ExprCompare(Parse*,Expr*, Expr*, int);
3803 int sqlite3ExprCompareSkip(Expr*, Expr*, int);
3804 int sqlite3ExprListCompare(ExprList*, ExprList*, int);
3805 int sqlite3ExprImpliesExpr(Parse*,Expr*, Expr*, int);
3806 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
3807 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
3808 int sqlite3ExprCoveredByIndex(Expr*, int iCur, Index *pIdx);
3809 int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
3810 Vdbe *sqlite3GetVdbe(Parse*);
3811 #ifndef SQLITE_UNTESTABLE
3812 void sqlite3PrngSaveState(void);
3813 void sqlite3PrngRestoreState(void);
3814 #endif
3815 void sqlite3RollbackAll(sqlite3*,int);
3816 void sqlite3CodeVerifySchema(Parse*, int);
3817 void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
3818 void sqlite3BeginTransaction(Parse*, int);
3819 void sqlite3EndTransaction(Parse*,int);
3820 void sqlite3Savepoint(Parse*, int, Token*);
3821 void sqlite3CloseSavepoints(sqlite3 *);
3822 void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
3823 int sqlite3ExprIsConstant(Expr*);
3824 int sqlite3ExprIsConstantNotJoin(Expr*);
3825 int sqlite3ExprIsConstantOrFunction(Expr*, u8);
3826 int sqlite3ExprIsConstantOrGroupBy(Parse*, Expr*, ExprList*);
3827 int sqlite3ExprIsTableConstant(Expr*,int);
3828 #ifdef SQLITE_ENABLE_CURSOR_HINTS
3829 int sqlite3ExprContainsSubquery(Expr*);
3830 #endif
3831 int sqlite3ExprIsInteger(Expr*, int*);
3832 int sqlite3ExprCanBeNull(const Expr*);
3833 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
3834 int sqlite3IsRowid(const char*);
3835 void sqlite3GenerateRowDelete(
3836     Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8,int);
3837 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*, int);
3838 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
3839 void sqlite3ResolvePartIdxLabel(Parse*,int);
3840 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
3841                                      u8,u8,int,int*,int*);
3842 #ifdef SQLITE_ENABLE_NULL_TRIM
3843   void sqlite3SetMakeRecordP5(Vdbe*,Table*);
3844 #else
3845 # define sqlite3SetMakeRecordP5(A,B)
3846 #endif
3847 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
3848 int sqlite3OpenTableAndIndices(Parse*, Table*, int, u8, int, u8*, int*, int*);
3849 void sqlite3BeginWriteOperation(Parse*, int, int);
3850 void sqlite3MultiWrite(Parse*);
3851 void sqlite3MayAbort(Parse*);
3852 void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
3853 void sqlite3UniqueConstraint(Parse*, int, Index*);
3854 void sqlite3RowidConstraint(Parse*, int, Table*);
3855 Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
3856 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
3857 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
3858 IdList *sqlite3IdListDup(sqlite3*,IdList*);
3859 Select *sqlite3SelectDup(sqlite3*,Select*,int);
3860 #if SELECTTRACE_ENABLED
3861 void sqlite3SelectSetName(Select*,const char*);
3862 #else
3863 # define sqlite3SelectSetName(A,B)
3864 #endif
3865 void sqlite3InsertBuiltinFuncs(FuncDef*,int);
3866 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,u8,u8);
3867 void sqlite3RegisterBuiltinFunctions(void);
3868 void sqlite3RegisterDateTimeFunctions(void);
3869 void sqlite3RegisterPerConnectionBuiltinFunctions(sqlite3*);
3870 int sqlite3SafetyCheckOk(sqlite3*);
3871 int sqlite3SafetyCheckSickOrOk(sqlite3*);
3872 void sqlite3ChangeCookie(Parse*, int);
3873 
3874 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
3875 void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
3876 #endif
3877 
3878 #ifndef SQLITE_OMIT_TRIGGER
3879   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
3880                            Expr*,int, int);
3881   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
3882   void sqlite3DropTrigger(Parse*, SrcList*, int);
3883   void sqlite3DropTriggerPtr(Parse*, Trigger*);
3884   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
3885   Trigger *sqlite3TriggerList(Parse *, Table *);
3886   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
3887                             int, int, int);
3888   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
3889   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
3890   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
3891   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
3892   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
3893                                         Select*,u8);
3894   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
3895   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
3896   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
3897   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
3898   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
3899 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
3900 # define sqlite3IsToplevel(p) ((p)->pToplevel==0)
3901 #else
3902 # define sqlite3TriggersExist(B,C,D,E,F) 0
3903 # define sqlite3DeleteTrigger(A,B)
3904 # define sqlite3DropTriggerPtr(A,B)
3905 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
3906 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
3907 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
3908 # define sqlite3TriggerList(X, Y) 0
3909 # define sqlite3ParseToplevel(p) p
3910 # define sqlite3IsToplevel(p) 1
3911 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
3912 #endif
3913 
3914 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
3915 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
3916 void sqlite3DeferForeignKey(Parse*, int);
3917 #ifndef SQLITE_OMIT_AUTHORIZATION
3918   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
3919   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
3920   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
3921   void sqlite3AuthContextPop(AuthContext*);
3922   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
3923 #else
3924 # define sqlite3AuthRead(a,b,c,d)
3925 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
3926 # define sqlite3AuthContextPush(a,b,c)
3927 # define sqlite3AuthContextPop(a)  ((void)(a))
3928 #endif
3929 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
3930 void sqlite3Detach(Parse*, Expr*);
3931 void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
3932 int sqlite3FixSrcList(DbFixer*, SrcList*);
3933 int sqlite3FixSelect(DbFixer*, Select*);
3934 int sqlite3FixExpr(DbFixer*, Expr*);
3935 int sqlite3FixExprList(DbFixer*, ExprList*);
3936 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
3937 int sqlite3AtoF(const char *z, double*, int, u8);
3938 int sqlite3GetInt32(const char *, int*);
3939 int sqlite3Atoi(const char*);
3940 #ifndef SQLITE_OMIT_UTF16
3941 int sqlite3Utf16ByteLen(const void *pData, int nChar);
3942 #endif
3943 int sqlite3Utf8CharLen(const char *pData, int nByte);
3944 u32 sqlite3Utf8Read(const u8**);
3945 LogEst sqlite3LogEst(u64);
3946 LogEst sqlite3LogEstAdd(LogEst,LogEst);
3947 #ifndef SQLITE_OMIT_VIRTUALTABLE
3948 LogEst sqlite3LogEstFromDouble(double);
3949 #endif
3950 #if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \
3951     defined(SQLITE_ENABLE_STAT3_OR_STAT4) || \
3952     defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
3953 u64 sqlite3LogEstToInt(LogEst);
3954 #endif
3955 VList *sqlite3VListAdd(sqlite3*,VList*,const char*,int,int);
3956 const char *sqlite3VListNumToName(VList*,int);
3957 int sqlite3VListNameToNum(VList*,const char*,int);
3958 
3959 /*
3960 ** Routines to read and write variable-length integers.  These used to
3961 ** be defined locally, but now we use the varint routines in the util.c
3962 ** file.
3963 */
3964 int sqlite3PutVarint(unsigned char*, u64);
3965 u8 sqlite3GetVarint(const unsigned char *, u64 *);
3966 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
3967 int sqlite3VarintLen(u64 v);
3968 
3969 /*
3970 ** The common case is for a varint to be a single byte.  They following
3971 ** macros handle the common case without a procedure call, but then call
3972 ** the procedure for larger varints.
3973 */
3974 #define getVarint32(A,B)  \
3975   (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
3976 #define putVarint32(A,B)  \
3977   (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
3978   sqlite3PutVarint((A),(B)))
3979 #define getVarint    sqlite3GetVarint
3980 #define putVarint    sqlite3PutVarint
3981 
3982 
3983 const char *sqlite3IndexAffinityStr(sqlite3*, Index*);
3984 void sqlite3TableAffinity(Vdbe*, Table*, int);
3985 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
3986 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
3987 char sqlite3TableColumnAffinity(Table*,int);
3988 char sqlite3ExprAffinity(Expr *pExpr);
3989 int sqlite3Atoi64(const char*, i64*, int, u8);
3990 int sqlite3DecOrHexToI64(const char*, i64*);
3991 void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
3992 void sqlite3Error(sqlite3*,int);
3993 void sqlite3SystemError(sqlite3*,int);
3994 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
3995 u8 sqlite3HexToInt(int h);
3996 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
3997 
3998 #if defined(SQLITE_NEED_ERR_NAME)
3999 const char *sqlite3ErrName(int);
4000 #endif
4001 
4002 const char *sqlite3ErrStr(int);
4003 int sqlite3ReadSchema(Parse *pParse);
4004 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
4005 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
4006 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
4007 Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*, int);
4008 Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
4009 Expr *sqlite3ExprSkipCollate(Expr*);
4010 int sqlite3CheckCollSeq(Parse *, CollSeq *);
4011 int sqlite3CheckObjectName(Parse *, const char *);
4012 void sqlite3VdbeSetChanges(sqlite3 *, int);
4013 int sqlite3AddInt64(i64*,i64);
4014 int sqlite3SubInt64(i64*,i64);
4015 int sqlite3MulInt64(i64*,i64);
4016 int sqlite3AbsInt32(int);
4017 #ifdef SQLITE_ENABLE_8_3_NAMES
4018 void sqlite3FileSuffix3(const char*, char*);
4019 #else
4020 # define sqlite3FileSuffix3(X,Y)
4021 #endif
4022 u8 sqlite3GetBoolean(const char *z,u8);
4023 
4024 const void *sqlite3ValueText(sqlite3_value*, u8);
4025 int sqlite3ValueBytes(sqlite3_value*, u8);
4026 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
4027                         void(*)(void*));
4028 void sqlite3ValueSetNull(sqlite3_value*);
4029 void sqlite3ValueFree(sqlite3_value*);
4030 sqlite3_value *sqlite3ValueNew(sqlite3 *);
4031 #ifndef SQLITE_OMIT_UTF16
4032 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
4033 #endif
4034 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
4035 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
4036 #ifndef SQLITE_AMALGAMATION
4037 extern const unsigned char sqlite3OpcodeProperty[];
4038 extern const char sqlite3StrBINARY[];
4039 extern const unsigned char sqlite3UpperToLower[];
4040 extern const unsigned char sqlite3CtypeMap[];
4041 extern const Token sqlite3IntTokens[];
4042 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
4043 extern FuncDefHash sqlite3BuiltinFunctions;
4044 #ifndef SQLITE_OMIT_WSD
4045 extern int sqlite3PendingByte;
4046 #endif
4047 #endif
4048 void sqlite3RootPageMoved(sqlite3*, int, int, int);
4049 void sqlite3Reindex(Parse*, Token*, Token*);
4050 void sqlite3AlterFunctions(void);
4051 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
4052 int sqlite3GetToken(const unsigned char *, int *);
4053 void sqlite3NestedParse(Parse*, const char*, ...);
4054 void sqlite3ExpirePreparedStatements(sqlite3*);
4055 int sqlite3CodeSubselect(Parse*, Expr *, int, int);
4056 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
4057 void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
4058 int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
4059 int sqlite3ResolveExprNames(NameContext*, Expr*);
4060 int sqlite3ResolveExprListNames(NameContext*, ExprList*);
4061 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
4062 void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
4063 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
4064 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
4065 void sqlite3AlterFinishAddColumn(Parse *, Token *);
4066 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
4067 CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
4068 char sqlite3AffinityType(const char*, u8*);
4069 void sqlite3Analyze(Parse*, Token*, Token*);
4070 int sqlite3InvokeBusyHandler(BusyHandler*);
4071 int sqlite3FindDb(sqlite3*, Token*);
4072 int sqlite3FindDbName(sqlite3 *, const char *);
4073 int sqlite3AnalysisLoad(sqlite3*,int iDB);
4074 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
4075 void sqlite3DefaultRowEst(Index*);
4076 void sqlite3RegisterLikeFunctions(sqlite3*, int);
4077 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
4078 void sqlite3SchemaClear(void *);
4079 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
4080 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
4081 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
4082 void sqlite3KeyInfoUnref(KeyInfo*);
4083 KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
4084 KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
4085 #ifdef SQLITE_DEBUG
4086 int sqlite3KeyInfoIsWriteable(KeyInfo*);
4087 #endif
4088 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
4089   void (*)(sqlite3_context*,int,sqlite3_value **),
4090   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
4091   FuncDestructor *pDestructor
4092 );
4093 void sqlite3OomFault(sqlite3*);
4094 void sqlite3OomClear(sqlite3*);
4095 int sqlite3ApiExit(sqlite3 *db, int);
4096 int sqlite3OpenTempDatabase(Parse *);
4097 
4098 void sqlite3StrAccumInit(StrAccum*, sqlite3*, char*, int, int);
4099 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
4100 void sqlite3StrAccumAppendAll(StrAccum*,const char*);
4101 void sqlite3AppendChar(StrAccum*,int,char);
4102 char *sqlite3StrAccumFinish(StrAccum*);
4103 void sqlite3StrAccumReset(StrAccum*);
4104 void sqlite3SelectDestInit(SelectDest*,int,int);
4105 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
4106 
4107 void sqlite3BackupRestart(sqlite3_backup *);
4108 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
4109 
4110 #ifndef SQLITE_OMIT_SUBQUERY
4111 int sqlite3ExprCheckIN(Parse*, Expr*);
4112 #else
4113 # define sqlite3ExprCheckIN(x,y) SQLITE_OK
4114 #endif
4115 
4116 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
4117 void sqlite3AnalyzeFunctions(void);
4118 int sqlite3Stat4ProbeSetValue(
4119     Parse*,Index*,UnpackedRecord**,Expr*,int,int,int*);
4120 int sqlite3Stat4ValueFromExpr(Parse*, Expr*, u8, sqlite3_value**);
4121 void sqlite3Stat4ProbeFree(UnpackedRecord*);
4122 int sqlite3Stat4Column(sqlite3*, const void*, int, int, sqlite3_value**);
4123 char sqlite3IndexColumnAffinity(sqlite3*, Index*, int);
4124 #endif
4125 
4126 /*
4127 ** The interface to the LEMON-generated parser
4128 */
4129 #ifndef SQLITE_AMALGAMATION
4130   void *sqlite3ParserAlloc(void*(*)(u64));
4131   void sqlite3ParserFree(void*, void(*)(void*));
4132 #endif
4133 void sqlite3Parser(void*, int, Token, Parse*);
4134 #ifdef YYTRACKMAXSTACKDEPTH
4135   int sqlite3ParserStackPeak(void*);
4136 #endif
4137 
4138 void sqlite3AutoLoadExtensions(sqlite3*);
4139 #ifndef SQLITE_OMIT_LOAD_EXTENSION
4140   void sqlite3CloseExtensions(sqlite3*);
4141 #else
4142 # define sqlite3CloseExtensions(X)
4143 #endif
4144 
4145 #ifndef SQLITE_OMIT_SHARED_CACHE
4146   void sqlite3TableLock(Parse *, int, int, u8, const char *);
4147 #else
4148   #define sqlite3TableLock(v,w,x,y,z)
4149 #endif
4150 
4151 #ifdef SQLITE_TEST
4152   int sqlite3Utf8To8(unsigned char*);
4153 #endif
4154 
4155 #ifdef SQLITE_OMIT_VIRTUALTABLE
4156 #  define sqlite3VtabClear(Y)
4157 #  define sqlite3VtabSync(X,Y) SQLITE_OK
4158 #  define sqlite3VtabRollback(X)
4159 #  define sqlite3VtabCommit(X)
4160 #  define sqlite3VtabInSync(db) 0
4161 #  define sqlite3VtabLock(X)
4162 #  define sqlite3VtabUnlock(X)
4163 #  define sqlite3VtabUnlockList(X)
4164 #  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
4165 #  define sqlite3GetVTable(X,Y)  ((VTable*)0)
4166 #else
4167    void sqlite3VtabClear(sqlite3 *db, Table*);
4168    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
4169    int sqlite3VtabSync(sqlite3 *db, Vdbe*);
4170    int sqlite3VtabRollback(sqlite3 *db);
4171    int sqlite3VtabCommit(sqlite3 *db);
4172    void sqlite3VtabLock(VTable *);
4173    void sqlite3VtabUnlock(VTable *);
4174    void sqlite3VtabUnlockList(sqlite3*);
4175    int sqlite3VtabSavepoint(sqlite3 *, int, int);
4176    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
4177    VTable *sqlite3GetVTable(sqlite3*, Table*);
4178    Module *sqlite3VtabCreateModule(
4179      sqlite3*,
4180      const char*,
4181      const sqlite3_module*,
4182      void*,
4183      void(*)(void*)
4184    );
4185 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
4186 #endif
4187 int sqlite3VtabEponymousTableInit(Parse*,Module*);
4188 void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
4189 void sqlite3VtabMakeWritable(Parse*,Table*);
4190 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
4191 void sqlite3VtabFinishParse(Parse*, Token*);
4192 void sqlite3VtabArgInit(Parse*);
4193 void sqlite3VtabArgExtend(Parse*, Token*);
4194 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
4195 int sqlite3VtabCallConnect(Parse*, Table*);
4196 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
4197 int sqlite3VtabBegin(sqlite3 *, VTable *);
4198 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
4199 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
4200 sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
4201 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
4202 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
4203 void sqlite3ParserReset(Parse*);
4204 int sqlite3Reprepare(Vdbe*);
4205 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
4206 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
4207 int sqlite3TempInMemory(const sqlite3*);
4208 const char *sqlite3JournalModename(int);
4209 #ifndef SQLITE_OMIT_WAL
4210   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
4211   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
4212 #endif
4213 #ifndef SQLITE_OMIT_CTE
4214   With *sqlite3WithAdd(Parse*,With*,Token*,ExprList*,Select*);
4215   void sqlite3WithDelete(sqlite3*,With*);
4216   void sqlite3WithPush(Parse*, With*, u8);
4217 #else
4218 #define sqlite3WithPush(x,y,z)
4219 #define sqlite3WithDelete(x,y)
4220 #endif
4221 
4222 /* Declarations for functions in fkey.c. All of these are replaced by
4223 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
4224 ** key functionality is available. If OMIT_TRIGGER is defined but
4225 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
4226 ** this case foreign keys are parsed, but no other functionality is
4227 ** provided (enforcement of FK constraints requires the triggers sub-system).
4228 */
4229 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
4230   void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
4231   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
4232   void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
4233   int sqlite3FkRequired(Parse*, Table*, int*, int);
4234   u32 sqlite3FkOldmask(Parse*, Table*);
4235   FKey *sqlite3FkReferences(Table *);
4236 #else
4237   #define sqlite3FkActions(a,b,c,d,e,f)
4238   #define sqlite3FkCheck(a,b,c,d,e,f)
4239   #define sqlite3FkDropTable(a,b,c)
4240   #define sqlite3FkOldmask(a,b)         0
4241   #define sqlite3FkRequired(a,b,c,d)    0
4242   #define sqlite3FkReferences(a)        0
4243 #endif
4244 #ifndef SQLITE_OMIT_FOREIGN_KEY
4245   void sqlite3FkDelete(sqlite3 *, Table*);
4246   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
4247 #else
4248   #define sqlite3FkDelete(a,b)
4249   #define sqlite3FkLocateIndex(a,b,c,d,e)
4250 #endif
4251 
4252 
4253 /*
4254 ** Available fault injectors.  Should be numbered beginning with 0.
4255 */
4256 #define SQLITE_FAULTINJECTOR_MALLOC     0
4257 #define SQLITE_FAULTINJECTOR_COUNT      1
4258 
4259 /*
4260 ** The interface to the code in fault.c used for identifying "benign"
4261 ** malloc failures. This is only present if SQLITE_UNTESTABLE
4262 ** is not defined.
4263 */
4264 #ifndef SQLITE_UNTESTABLE
4265   void sqlite3BeginBenignMalloc(void);
4266   void sqlite3EndBenignMalloc(void);
4267 #else
4268   #define sqlite3BeginBenignMalloc()
4269   #define sqlite3EndBenignMalloc()
4270 #endif
4271 
4272 /*
4273 ** Allowed return values from sqlite3FindInIndex()
4274 */
4275 #define IN_INDEX_ROWID        1   /* Search the rowid of the table */
4276 #define IN_INDEX_EPH          2   /* Search an ephemeral b-tree */
4277 #define IN_INDEX_INDEX_ASC    3   /* Existing index ASCENDING */
4278 #define IN_INDEX_INDEX_DESC   4   /* Existing index DESCENDING */
4279 #define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
4280 /*
4281 ** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
4282 */
4283 #define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
4284 #define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
4285 #define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
4286 int sqlite3FindInIndex(Parse *, Expr *, u32, int*, int*);
4287 
4288 int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
4289 int sqlite3JournalSize(sqlite3_vfs *);
4290 #if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
4291  || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
4292   int sqlite3JournalCreate(sqlite3_file *);
4293 #endif
4294 
4295 int sqlite3JournalIsInMemory(sqlite3_file *p);
4296 void sqlite3MemJournalOpen(sqlite3_file *);
4297 
4298 void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p);
4299 #if SQLITE_MAX_EXPR_DEPTH>0
4300   int sqlite3SelectExprHeight(Select *);
4301   int sqlite3ExprCheckHeight(Parse*, int);
4302 #else
4303   #define sqlite3SelectExprHeight(x) 0
4304   #define sqlite3ExprCheckHeight(x,y)
4305 #endif
4306 
4307 u32 sqlite3Get4byte(const u8*);
4308 void sqlite3Put4byte(u8*, u32);
4309 
4310 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
4311   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
4312   void sqlite3ConnectionUnlocked(sqlite3 *db);
4313   void sqlite3ConnectionClosed(sqlite3 *db);
4314 #else
4315   #define sqlite3ConnectionBlocked(x,y)
4316   #define sqlite3ConnectionUnlocked(x)
4317   #define sqlite3ConnectionClosed(x)
4318 #endif
4319 
4320 #ifdef SQLITE_DEBUG
4321   void sqlite3ParserTrace(FILE*, char *);
4322 #endif
4323 
4324 /*
4325 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
4326 ** sqlite3IoTrace is a pointer to a printf-like routine used to
4327 ** print I/O tracing messages.
4328 */
4329 #ifdef SQLITE_ENABLE_IOTRACE
4330 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
4331   void sqlite3VdbeIOTraceSql(Vdbe*);
4332 SQLITE_API SQLITE_EXTERN void (SQLITE_CDECL *sqlite3IoTrace)(const char*,...);
4333 #else
4334 # define IOTRACE(A)
4335 # define sqlite3VdbeIOTraceSql(X)
4336 #endif
4337 
4338 /*
4339 ** These routines are available for the mem2.c debugging memory allocator
4340 ** only.  They are used to verify that different "types" of memory
4341 ** allocations are properly tracked by the system.
4342 **
4343 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
4344 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
4345 ** a single bit set.
4346 **
4347 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
4348 ** argument match the type set by the previous sqlite3MemdebugSetType().
4349 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
4350 **
4351 ** sqlite3MemdebugNoType() returns true if none of the bits in its second
4352 ** argument match the type set by the previous sqlite3MemdebugSetType().
4353 **
4354 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
4355 ** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
4356 ** it might have been allocated by lookaside, except the allocation was
4357 ** too large or lookaside was already full.  It is important to verify
4358 ** that allocations that might have been satisfied by lookaside are not
4359 ** passed back to non-lookaside free() routines.  Asserts such as the
4360 ** example above are placed on the non-lookaside free() routines to verify
4361 ** this constraint.
4362 **
4363 ** All of this is no-op for a production build.  It only comes into
4364 ** play when the SQLITE_MEMDEBUG compile-time option is used.
4365 */
4366 #ifdef SQLITE_MEMDEBUG
4367   void sqlite3MemdebugSetType(void*,u8);
4368   int sqlite3MemdebugHasType(void*,u8);
4369   int sqlite3MemdebugNoType(void*,u8);
4370 #else
4371 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
4372 # define sqlite3MemdebugHasType(X,Y)  1
4373 # define sqlite3MemdebugNoType(X,Y)   1
4374 #endif
4375 #define MEMTYPE_HEAP       0x01  /* General heap allocations */
4376 #define MEMTYPE_LOOKASIDE  0x02  /* Heap that might have been lookaside */
4377 #define MEMTYPE_PCACHE     0x04  /* Page cache allocations */
4378 
4379 /*
4380 ** Threading interface
4381 */
4382 #if SQLITE_MAX_WORKER_THREADS>0
4383 int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
4384 int sqlite3ThreadJoin(SQLiteThread*, void**);
4385 #endif
4386 
4387 #if defined(SQLITE_ENABLE_DBSTAT_VTAB) || defined(SQLITE_TEST)
4388 int sqlite3DbstatRegister(sqlite3*);
4389 #endif
4390 
4391 int sqlite3ExprVectorSize(Expr *pExpr);
4392 int sqlite3ExprIsVector(Expr *pExpr);
4393 Expr *sqlite3VectorFieldSubexpr(Expr*, int);
4394 Expr *sqlite3ExprForVectorField(Parse*,Expr*,int);
4395 void sqlite3VectorErrorMsg(Parse*, Expr*);
4396 
4397 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
4398 const char **sqlite3CompileOptions(int *pnOpt);
4399 #endif
4400 
4401 #endif /* SQLITEINT_H */
4402