xref: /sqlite-3.40.0/src/sqliteInt.h (revision 9684d710)
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 /*
123 ** Some C99 functions in "math.h" are only present for MSVC when its version
124 ** is associated with Visual Studio 2013 or higher.
125 */
126 #ifndef SQLITE_HAVE_C99_MATH_FUNCS
127 # if MSVC_VERSION==0 || MSVC_VERSION>=1800
128 #  define SQLITE_HAVE_C99_MATH_FUNCS (1)
129 # else
130 #  define SQLITE_HAVE_C99_MATH_FUNCS (0)
131 # endif
132 #endif
133 
134 /* Needed for various definitions... */
135 #if defined(__GNUC__) && !defined(_GNU_SOURCE)
136 # define _GNU_SOURCE
137 #endif
138 
139 #if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
140 # define _BSD_SOURCE
141 #endif
142 
143 /*
144 ** Macro to disable warnings about missing "break" at the end of a "case".
145 */
146 #if GCC_VERSION>=7000000
147 # define deliberate_fall_through __attribute__((fallthrough));
148 #else
149 # define deliberate_fall_through
150 #endif
151 
152 /*
153 ** For MinGW, check to see if we can include the header file containing its
154 ** version information, among other things.  Normally, this internal MinGW
155 ** header file would [only] be included automatically by other MinGW header
156 ** files; however, the contained version information is now required by this
157 ** header file to work around binary compatibility issues (see below) and
158 ** this is the only known way to reliably obtain it.  This entire #if block
159 ** would be completely unnecessary if there was any other way of detecting
160 ** MinGW via their preprocessor (e.g. if they customized their GCC to define
161 ** some MinGW-specific macros).  When compiling for MinGW, either the
162 ** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
163 ** defined; otherwise, detection of conditions specific to MinGW will be
164 ** disabled.
165 */
166 #if defined(_HAVE_MINGW_H)
167 # include "mingw.h"
168 #elif defined(_HAVE__MINGW_H)
169 # include "_mingw.h"
170 #endif
171 
172 /*
173 ** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
174 ** define is required to maintain binary compatibility with the MSVC runtime
175 ** library in use (e.g. for Windows XP).
176 */
177 #if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
178     defined(_WIN32) && !defined(_WIN64) && \
179     defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
180     defined(__MSVCRT__)
181 # define _USE_32BIT_TIME_T
182 #endif
183 
184 /* Optionally #include a user-defined header, whereby compilation options
185 ** may be set prior to where they take effect, but after platform setup.
186 ** If SQLITE_CUSTOM_INCLUDE=? is defined, its value names the #include
187 ** file.
188 */
189 #ifdef SQLITE_CUSTOM_INCLUDE
190 # define INC_STRINGIFY_(f) #f
191 # define INC_STRINGIFY(f) INC_STRINGIFY_(f)
192 # include INC_STRINGIFY(SQLITE_CUSTOM_INCLUDE)
193 #endif
194 
195 /* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
196 ** first in QNX.  Also, the _USE_32BIT_TIME_T macro must appear first for
197 ** MinGW.
198 */
199 #include "sqlite3.h"
200 
201 /*
202 ** Include the configuration header output by 'configure' if we're using the
203 ** autoconf-based build
204 */
205 #if defined(_HAVE_SQLITE_CONFIG_H) && !defined(SQLITECONFIG_H)
206 #include "config.h"
207 #define SQLITECONFIG_H 1
208 #endif
209 
210 #include "sqliteLimit.h"
211 
212 /* Disable nuisance warnings on Borland compilers */
213 #if defined(__BORLANDC__)
214 #pragma warn -rch /* unreachable code */
215 #pragma warn -ccc /* Condition is always true or false */
216 #pragma warn -aus /* Assigned value is never used */
217 #pragma warn -csu /* Comparing signed and unsigned */
218 #pragma warn -spa /* Suspicious pointer arithmetic */
219 #endif
220 
221 /*
222 ** WAL mode depends on atomic aligned 32-bit loads and stores in a few
223 ** places.  The following macros try to make this explicit.
224 */
225 #ifndef __has_extension
226 # define __has_extension(x) 0     /* compatibility with non-clang compilers */
227 #endif
228 #if GCC_VERSION>=4007000 || __has_extension(c_atomic)
229 # define SQLITE_ATOMIC_INTRINSICS 1
230 # define AtomicLoad(PTR)       __atomic_load_n((PTR),__ATOMIC_RELAXED)
231 # define AtomicStore(PTR,VAL)  __atomic_store_n((PTR),(VAL),__ATOMIC_RELAXED)
232 #else
233 # define SQLITE_ATOMIC_INTRINSICS 0
234 # define AtomicLoad(PTR)       (*(PTR))
235 # define AtomicStore(PTR,VAL)  (*(PTR) = (VAL))
236 #endif
237 
238 /*
239 ** Include standard header files as necessary
240 */
241 #ifdef HAVE_STDINT_H
242 #include <stdint.h>
243 #endif
244 #ifdef HAVE_INTTYPES_H
245 #include <inttypes.h>
246 #endif
247 
248 /*
249 ** The following macros are used to cast pointers to integers and
250 ** integers to pointers.  The way you do this varies from one compiler
251 ** to the next, so we have developed the following set of #if statements
252 ** to generate appropriate macros for a wide range of compilers.
253 **
254 ** The correct "ANSI" way to do this is to use the intptr_t type.
255 ** Unfortunately, that typedef is not available on all compilers, or
256 ** if it is available, it requires an #include of specific headers
257 ** that vary from one machine to the next.
258 **
259 ** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
260 ** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
261 ** So we have to define the macros in different ways depending on the
262 ** compiler.
263 */
264 #if defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
265 # define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
266 # define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
267 #elif defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
268 # define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
269 # define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
270 #elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
271 # define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
272 # define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
273 #else                          /* Generates a warning - but it always works */
274 # define SQLITE_INT_TO_PTR(X)  ((void*)(X))
275 # define SQLITE_PTR_TO_INT(X)  ((int)(X))
276 #endif
277 
278 /*
279 ** A macro to hint to the compiler that a function should not be
280 ** inlined.
281 */
282 #if defined(__GNUC__)
283 #  define SQLITE_NOINLINE  __attribute__((noinline))
284 #elif defined(_MSC_VER) && _MSC_VER>=1310
285 #  define SQLITE_NOINLINE  __declspec(noinline)
286 #else
287 #  define SQLITE_NOINLINE
288 #endif
289 
290 /*
291 ** Make sure that the compiler intrinsics we desire are enabled when
292 ** compiling with an appropriate version of MSVC unless prevented by
293 ** the SQLITE_DISABLE_INTRINSIC define.
294 */
295 #if !defined(SQLITE_DISABLE_INTRINSIC)
296 #  if defined(_MSC_VER) && _MSC_VER>=1400
297 #    if !defined(_WIN32_WCE)
298 #      include <intrin.h>
299 #      pragma intrinsic(_byteswap_ushort)
300 #      pragma intrinsic(_byteswap_ulong)
301 #      pragma intrinsic(_byteswap_uint64)
302 #      pragma intrinsic(_ReadWriteBarrier)
303 #    else
304 #      include <cmnintrin.h>
305 #    endif
306 #  endif
307 #endif
308 
309 /*
310 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
311 ** 0 means mutexes are permanently disable and the library is never
312 ** threadsafe.  1 means the library is serialized which is the highest
313 ** level of threadsafety.  2 means the library is multithreaded - multiple
314 ** threads can use SQLite as long as no two threads try to use the same
315 ** database connection at the same time.
316 **
317 ** Older versions of SQLite used an optional THREADSAFE macro.
318 ** We support that for legacy.
319 **
320 ** To ensure that the correct value of "THREADSAFE" is reported when querying
321 ** for compile-time options at runtime (e.g. "PRAGMA compile_options"), this
322 ** logic is partially replicated in ctime.c. If it is updated here, it should
323 ** also be updated there.
324 */
325 #if !defined(SQLITE_THREADSAFE)
326 # if defined(THREADSAFE)
327 #   define SQLITE_THREADSAFE THREADSAFE
328 # else
329 #   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
330 # endif
331 #endif
332 
333 /*
334 ** Powersafe overwrite is on by default.  But can be turned off using
335 ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
336 */
337 #ifndef SQLITE_POWERSAFE_OVERWRITE
338 # define SQLITE_POWERSAFE_OVERWRITE 1
339 #endif
340 
341 /*
342 ** EVIDENCE-OF: R-25715-37072 Memory allocation statistics are enabled by
343 ** default unless SQLite is compiled with SQLITE_DEFAULT_MEMSTATUS=0 in
344 ** which case memory allocation statistics are disabled by default.
345 */
346 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
347 # define SQLITE_DEFAULT_MEMSTATUS 1
348 #endif
349 
350 /*
351 ** Exactly one of the following macros must be defined in order to
352 ** specify which memory allocation subsystem to use.
353 **
354 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
355 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
356 **     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
357 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
358 **
359 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
360 ** assert() macro is enabled, each call into the Win32 native heap subsystem
361 ** will cause HeapValidate to be called.  If heap validation should fail, an
362 ** assertion will be triggered.
363 **
364 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
365 ** the default.
366 */
367 #if defined(SQLITE_SYSTEM_MALLOC) \
368   + defined(SQLITE_WIN32_MALLOC) \
369   + defined(SQLITE_ZERO_MALLOC) \
370   + defined(SQLITE_MEMDEBUG)>1
371 # error "Two or more of the following compile-time configuration options\
372  are defined but at most one is allowed:\
373  SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
374  SQLITE_ZERO_MALLOC"
375 #endif
376 #if defined(SQLITE_SYSTEM_MALLOC) \
377   + defined(SQLITE_WIN32_MALLOC) \
378   + defined(SQLITE_ZERO_MALLOC) \
379   + defined(SQLITE_MEMDEBUG)==0
380 # define SQLITE_SYSTEM_MALLOC 1
381 #endif
382 
383 /*
384 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
385 ** sizes of memory allocations below this value where possible.
386 */
387 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
388 # define SQLITE_MALLOC_SOFT_LIMIT 1024
389 #endif
390 
391 /*
392 ** We need to define _XOPEN_SOURCE as follows in order to enable
393 ** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
394 ** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
395 ** it.
396 */
397 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
398 #  define _XOPEN_SOURCE 600
399 #endif
400 
401 /*
402 ** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
403 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
404 ** make it true by defining or undefining NDEBUG.
405 **
406 ** Setting NDEBUG makes the code smaller and faster by disabling the
407 ** assert() statements in the code.  So we want the default action
408 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
409 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
410 ** feature.
411 */
412 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
413 # define NDEBUG 1
414 #endif
415 #if defined(NDEBUG) && defined(SQLITE_DEBUG)
416 # undef NDEBUG
417 #endif
418 
419 /*
420 ** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
421 */
422 #if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
423 # define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
424 #endif
425 
426 /*
427 ** The testcase() macro is used to aid in coverage testing.  When
428 ** doing coverage testing, the condition inside the argument to
429 ** testcase() must be evaluated both true and false in order to
430 ** get full branch coverage.  The testcase() macro is inserted
431 ** to help ensure adequate test coverage in places where simple
432 ** condition/decision coverage is inadequate.  For example, testcase()
433 ** can be used to make sure boundary values are tested.  For
434 ** bitmask tests, testcase() can be used to make sure each bit
435 ** is significant and used at least once.  On switch statements
436 ** where multiple cases go to the same block of code, testcase()
437 ** can insure that all cases are evaluated.
438 */
439 #if defined(SQLITE_COVERAGE_TEST) || defined(SQLITE_DEBUG)
440 # ifndef SQLITE_AMALGAMATION
441     extern unsigned int sqlite3CoverageCounter;
442 # endif
443 # define testcase(X)  if( X ){ sqlite3CoverageCounter += (unsigned)__LINE__; }
444 #else
445 # define testcase(X)
446 #endif
447 
448 /*
449 ** The TESTONLY macro is used to enclose variable declarations or
450 ** other bits of code that are needed to support the arguments
451 ** within testcase() and assert() macros.
452 */
453 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
454 # define TESTONLY(X)  X
455 #else
456 # define TESTONLY(X)
457 #endif
458 
459 /*
460 ** Sometimes we need a small amount of code such as a variable initialization
461 ** to setup for a later assert() statement.  We do not want this code to
462 ** appear when assert() is disabled.  The following macro is therefore
463 ** used to contain that setup code.  The "VVA" acronym stands for
464 ** "Verification, Validation, and Accreditation".  In other words, the
465 ** code within VVA_ONLY() will only run during verification processes.
466 */
467 #ifndef NDEBUG
468 # define VVA_ONLY(X)  X
469 #else
470 # define VVA_ONLY(X)
471 #endif
472 
473 /*
474 ** Disable ALWAYS() and NEVER() (make them pass-throughs) for coverage
475 ** and mutation testing
476 */
477 #if defined(SQLITE_COVERAGE_TEST) || defined(SQLITE_MUTATION_TEST)
478 # define SQLITE_OMIT_AUXILIARY_SAFETY_CHECKS  1
479 #endif
480 
481 /*
482 ** The ALWAYS and NEVER macros surround boolean expressions which
483 ** are intended to always be true or false, respectively.  Such
484 ** expressions could be omitted from the code completely.  But they
485 ** are included in a few cases in order to enhance the resilience
486 ** of SQLite to unexpected behavior - to make the code "self-healing"
487 ** or "ductile" rather than being "brittle" and crashing at the first
488 ** hint of unplanned behavior.
489 **
490 ** In other words, ALWAYS and NEVER are added for defensive code.
491 **
492 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
493 ** be true and false so that the unreachable code they specify will
494 ** not be counted as untested code.
495 */
496 #if defined(SQLITE_OMIT_AUXILIARY_SAFETY_CHECKS)
497 # define ALWAYS(X)      (1)
498 # define NEVER(X)       (0)
499 #elif !defined(NDEBUG)
500 # define ALWAYS(X)      ((X)?1:(assert(0),0))
501 # define NEVER(X)       ((X)?(assert(0),1):0)
502 #else
503 # define ALWAYS(X)      (X)
504 # define NEVER(X)       (X)
505 #endif
506 
507 /*
508 ** Some conditionals are optimizations only.  In other words, if the
509 ** conditionals are replaced with a constant 1 (true) or 0 (false) then
510 ** the correct answer is still obtained, though perhaps not as quickly.
511 **
512 ** The following macros mark these optimizations conditionals.
513 */
514 #if defined(SQLITE_MUTATION_TEST)
515 # define OK_IF_ALWAYS_TRUE(X)  (1)
516 # define OK_IF_ALWAYS_FALSE(X) (0)
517 #else
518 # define OK_IF_ALWAYS_TRUE(X)  (X)
519 # define OK_IF_ALWAYS_FALSE(X) (X)
520 #endif
521 
522 /*
523 ** Some malloc failures are only possible if SQLITE_TEST_REALLOC_STRESS is
524 ** defined.  We need to defend against those failures when testing with
525 ** SQLITE_TEST_REALLOC_STRESS, but we don't want the unreachable branches
526 ** during a normal build.  The following macro can be used to disable tests
527 ** that are always false except when SQLITE_TEST_REALLOC_STRESS is set.
528 */
529 #if defined(SQLITE_TEST_REALLOC_STRESS)
530 # define ONLY_IF_REALLOC_STRESS(X)  (X)
531 #elif !defined(NDEBUG)
532 # define ONLY_IF_REALLOC_STRESS(X)  ((X)?(assert(0),1):0)
533 #else
534 # define ONLY_IF_REALLOC_STRESS(X)  (0)
535 #endif
536 
537 /*
538 ** Declarations used for tracing the operating system interfaces.
539 */
540 #if defined(SQLITE_FORCE_OS_TRACE) || defined(SQLITE_TEST) || \
541     (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
542   extern int sqlite3OSTrace;
543 # define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
544 # define SQLITE_HAVE_OS_TRACE
545 #else
546 # define OSTRACE(X)
547 # undef  SQLITE_HAVE_OS_TRACE
548 #endif
549 
550 /*
551 ** Is the sqlite3ErrName() function needed in the build?  Currently,
552 ** it is needed by "mutex_w32.c" (when debugging), "os_win.c" (when
553 ** OSTRACE is enabled), and by several "test*.c" files (which are
554 ** compiled using SQLITE_TEST).
555 */
556 #if defined(SQLITE_HAVE_OS_TRACE) || defined(SQLITE_TEST) || \
557     (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
558 # define SQLITE_NEED_ERR_NAME
559 #else
560 # undef  SQLITE_NEED_ERR_NAME
561 #endif
562 
563 /*
564 ** SQLITE_ENABLE_EXPLAIN_COMMENTS is incompatible with SQLITE_OMIT_EXPLAIN
565 */
566 #ifdef SQLITE_OMIT_EXPLAIN
567 # undef SQLITE_ENABLE_EXPLAIN_COMMENTS
568 #endif
569 
570 /*
571 ** SQLITE_OMIT_VIRTUALTABLE implies SQLITE_OMIT_ALTERTABLE
572 */
573 #if defined(SQLITE_OMIT_VIRTUALTABLE) && !defined(SQLITE_OMIT_ALTERTABLE)
574 # define SQLITE_OMIT_ALTERTABLE
575 #endif
576 
577 /*
578 ** Return true (non-zero) if the input is an integer that is too large
579 ** to fit in 32-bits.  This macro is used inside of various testcase()
580 ** macros to verify that we have tested SQLite for large-file support.
581 */
582 #define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
583 
584 /*
585 ** The macro unlikely() is a hint that surrounds a boolean
586 ** expression that is usually false.  Macro likely() surrounds
587 ** a boolean expression that is usually true.  These hints could,
588 ** in theory, be used by the compiler to generate better code, but
589 ** currently they are just comments for human readers.
590 */
591 #define likely(X)    (X)
592 #define unlikely(X)  (X)
593 
594 #include "hash.h"
595 #include "parse.h"
596 #include <stdio.h>
597 #include <stdlib.h>
598 #include <string.h>
599 #include <assert.h>
600 #include <stddef.h>
601 
602 /*
603 ** Use a macro to replace memcpy() if compiled with SQLITE_INLINE_MEMCPY.
604 ** This allows better measurements of where memcpy() is used when running
605 ** cachegrind.  But this macro version of memcpy() is very slow so it
606 ** should not be used in production.  This is a performance measurement
607 ** hack only.
608 */
609 #ifdef SQLITE_INLINE_MEMCPY
610 # define memcpy(D,S,N) {char*xxd=(char*)(D);const char*xxs=(const char*)(S);\
611                         int xxn=(N);while(xxn-->0)*(xxd++)=*(xxs++);}
612 #endif
613 
614 /*
615 ** If compiling for a processor that lacks floating point support,
616 ** substitute integer for floating-point
617 */
618 #ifdef SQLITE_OMIT_FLOATING_POINT
619 # define double sqlite_int64
620 # define float sqlite_int64
621 # define LONGDOUBLE_TYPE sqlite_int64
622 # ifndef SQLITE_BIG_DBL
623 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
624 # endif
625 # define SQLITE_OMIT_DATETIME_FUNCS 1
626 # define SQLITE_OMIT_TRACE 1
627 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
628 # undef SQLITE_HAVE_ISNAN
629 #endif
630 #ifndef SQLITE_BIG_DBL
631 # define SQLITE_BIG_DBL (1e99)
632 #endif
633 
634 /*
635 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
636 ** afterward. Having this macro allows us to cause the C compiler
637 ** to omit code used by TEMP tables without messy #ifndef statements.
638 */
639 #ifdef SQLITE_OMIT_TEMPDB
640 #define OMIT_TEMPDB 1
641 #else
642 #define OMIT_TEMPDB 0
643 #endif
644 
645 /*
646 ** The "file format" number is an integer that is incremented whenever
647 ** the VDBE-level file format changes.  The following macros define the
648 ** the default file format for new databases and the maximum file format
649 ** that the library can read.
650 */
651 #define SQLITE_MAX_FILE_FORMAT 4
652 #ifndef SQLITE_DEFAULT_FILE_FORMAT
653 # define SQLITE_DEFAULT_FILE_FORMAT 4
654 #endif
655 
656 /*
657 ** Determine whether triggers are recursive by default.  This can be
658 ** changed at run-time using a pragma.
659 */
660 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
661 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
662 #endif
663 
664 /*
665 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
666 ** on the command-line
667 */
668 #ifndef SQLITE_TEMP_STORE
669 # define SQLITE_TEMP_STORE 1
670 #endif
671 
672 /*
673 ** If no value has been provided for SQLITE_MAX_WORKER_THREADS, or if
674 ** SQLITE_TEMP_STORE is set to 3 (never use temporary files), set it
675 ** to zero.
676 */
677 #if SQLITE_TEMP_STORE==3 || SQLITE_THREADSAFE==0
678 # undef SQLITE_MAX_WORKER_THREADS
679 # define SQLITE_MAX_WORKER_THREADS 0
680 #endif
681 #ifndef SQLITE_MAX_WORKER_THREADS
682 # define SQLITE_MAX_WORKER_THREADS 8
683 #endif
684 #ifndef SQLITE_DEFAULT_WORKER_THREADS
685 # define SQLITE_DEFAULT_WORKER_THREADS 0
686 #endif
687 #if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
688 # undef SQLITE_MAX_WORKER_THREADS
689 # define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
690 #endif
691 
692 /*
693 ** The default initial allocation for the pagecache when using separate
694 ** pagecaches for each database connection.  A positive number is the
695 ** number of pages.  A negative number N translations means that a buffer
696 ** of -1024*N bytes is allocated and used for as many pages as it will hold.
697 **
698 ** The default value of "20" was chosen to minimize the run-time of the
699 ** speedtest1 test program with options: --shrink-memory --reprepare
700 */
701 #ifndef SQLITE_DEFAULT_PCACHE_INITSZ
702 # define SQLITE_DEFAULT_PCACHE_INITSZ 20
703 #endif
704 
705 /*
706 ** Default value for the SQLITE_CONFIG_SORTERREF_SIZE option.
707 */
708 #ifndef SQLITE_DEFAULT_SORTERREF_SIZE
709 # define SQLITE_DEFAULT_SORTERREF_SIZE 0x7fffffff
710 #endif
711 
712 /*
713 ** The compile-time options SQLITE_MMAP_READWRITE and
714 ** SQLITE_ENABLE_BATCH_ATOMIC_WRITE are not compatible with one another.
715 ** You must choose one or the other (or neither) but not both.
716 */
717 #if defined(SQLITE_MMAP_READWRITE) && defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
718 #error Cannot use both SQLITE_MMAP_READWRITE and SQLITE_ENABLE_BATCH_ATOMIC_WRITE
719 #endif
720 
721 /*
722 ** GCC does not define the offsetof() macro so we'll have to do it
723 ** ourselves.
724 */
725 #ifndef offsetof
726 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
727 #endif
728 
729 /*
730 ** Macros to compute minimum and maximum of two numbers.
731 */
732 #ifndef MIN
733 # define MIN(A,B) ((A)<(B)?(A):(B))
734 #endif
735 #ifndef MAX
736 # define MAX(A,B) ((A)>(B)?(A):(B))
737 #endif
738 
739 /*
740 ** Swap two objects of type TYPE.
741 */
742 #define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
743 
744 /*
745 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
746 ** not, there are still machines out there that use EBCDIC.)
747 */
748 #if 'A' == '\301'
749 # define SQLITE_EBCDIC 1
750 #else
751 # define SQLITE_ASCII 1
752 #endif
753 
754 /*
755 ** Integers of known sizes.  These typedefs might change for architectures
756 ** where the sizes very.  Preprocessor macros are available so that the
757 ** types can be conveniently redefined at compile-type.  Like this:
758 **
759 **         cc '-DUINTPTR_TYPE=long long int' ...
760 */
761 #ifndef UINT32_TYPE
762 # ifdef HAVE_UINT32_T
763 #  define UINT32_TYPE uint32_t
764 # else
765 #  define UINT32_TYPE unsigned int
766 # endif
767 #endif
768 #ifndef UINT16_TYPE
769 # ifdef HAVE_UINT16_T
770 #  define UINT16_TYPE uint16_t
771 # else
772 #  define UINT16_TYPE unsigned short int
773 # endif
774 #endif
775 #ifndef INT16_TYPE
776 # ifdef HAVE_INT16_T
777 #  define INT16_TYPE int16_t
778 # else
779 #  define INT16_TYPE short int
780 # endif
781 #endif
782 #ifndef UINT8_TYPE
783 # ifdef HAVE_UINT8_T
784 #  define UINT8_TYPE uint8_t
785 # else
786 #  define UINT8_TYPE unsigned char
787 # endif
788 #endif
789 #ifndef INT8_TYPE
790 # ifdef HAVE_INT8_T
791 #  define INT8_TYPE int8_t
792 # else
793 #  define INT8_TYPE signed char
794 # endif
795 #endif
796 #ifndef LONGDOUBLE_TYPE
797 # define LONGDOUBLE_TYPE long double
798 #endif
799 typedef sqlite_int64 i64;          /* 8-byte signed integer */
800 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
801 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
802 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
803 typedef INT16_TYPE i16;            /* 2-byte signed integer */
804 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
805 typedef INT8_TYPE i8;              /* 1-byte signed integer */
806 
807 /*
808 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
809 ** that can be stored in a u32 without loss of data.  The value
810 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
811 ** have to specify the value in the less intuitive manner shown:
812 */
813 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
814 
815 /*
816 ** The datatype used to store estimates of the number of rows in a
817 ** table or index.  This is an unsigned integer type.  For 99.9% of
818 ** the world, a 32-bit integer is sufficient.  But a 64-bit integer
819 ** can be used at compile-time if desired.
820 */
821 #ifdef SQLITE_64BIT_STATS
822  typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
823 #else
824  typedef u32 tRowcnt;    /* 32-bit is the default */
825 #endif
826 
827 /*
828 ** Estimated quantities used for query planning are stored as 16-bit
829 ** logarithms.  For quantity X, the value stored is 10*log2(X).  This
830 ** gives a possible range of values of approximately 1.0e986 to 1e-986.
831 ** But the allowed values are "grainy".  Not every value is representable.
832 ** For example, quantities 16 and 17 are both represented by a LogEst
833 ** of 40.  However, since LogEst quantities are suppose to be estimates,
834 ** not exact values, this imprecision is not a problem.
835 **
836 ** "LogEst" is short for "Logarithmic Estimate".
837 **
838 ** Examples:
839 **      1 -> 0              20 -> 43          10000 -> 132
840 **      2 -> 10             25 -> 46          25000 -> 146
841 **      3 -> 16            100 -> 66        1000000 -> 199
842 **      4 -> 20           1000 -> 99        1048576 -> 200
843 **     10 -> 33           1024 -> 100    4294967296 -> 320
844 **
845 ** The LogEst can be negative to indicate fractional values.
846 ** Examples:
847 **
848 **    0.5 -> -10           0.1 -> -33        0.0625 -> -40
849 */
850 typedef INT16_TYPE LogEst;
851 
852 /*
853 ** Set the SQLITE_PTRSIZE macro to the number of bytes in a pointer
854 */
855 #ifndef SQLITE_PTRSIZE
856 # if defined(__SIZEOF_POINTER__)
857 #   define SQLITE_PTRSIZE __SIZEOF_POINTER__
858 # elif defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
859        defined(_M_ARM)   || defined(__arm__)    || defined(__x86)   ||    \
860       (defined(__APPLE__) && defined(__POWERPC__)) ||                     \
861       (defined(__TOS_AIX__) && !defined(__64BIT__))
862 #   define SQLITE_PTRSIZE 4
863 # else
864 #   define SQLITE_PTRSIZE 8
865 # endif
866 #endif
867 
868 /* The uptr type is an unsigned integer large enough to hold a pointer
869 */
870 #if defined(HAVE_STDINT_H)
871   typedef uintptr_t uptr;
872 #elif SQLITE_PTRSIZE==4
873   typedef u32 uptr;
874 #else
875   typedef u64 uptr;
876 #endif
877 
878 /*
879 ** The SQLITE_WITHIN(P,S,E) macro checks to see if pointer P points to
880 ** something between S (inclusive) and E (exclusive).
881 **
882 ** In other words, S is a buffer and E is a pointer to the first byte after
883 ** the end of buffer S.  This macro returns true if P points to something
884 ** contained within the buffer S.
885 */
886 #define SQLITE_WITHIN(P,S,E) (((uptr)(P)>=(uptr)(S))&&((uptr)(P)<(uptr)(E)))
887 
888 
889 /*
890 ** Macros to determine whether the machine is big or little endian,
891 ** and whether or not that determination is run-time or compile-time.
892 **
893 ** For best performance, an attempt is made to guess at the byte-order
894 ** using C-preprocessor macros.  If that is unsuccessful, or if
895 ** -DSQLITE_BYTEORDER=0 is set, then byte-order is determined
896 ** at run-time.
897 */
898 #ifndef SQLITE_BYTEORDER
899 # if defined(i386)      || defined(__i386__)      || defined(_M_IX86) ||    \
900      defined(__x86_64)  || defined(__x86_64__)    || defined(_M_X64)  ||    \
901      defined(_M_AMD64)  || defined(_M_ARM)        || defined(__x86)   ||    \
902      defined(__ARMEL__) || defined(__AARCH64EL__) || defined(_M_ARM64)
903 #   define SQLITE_BYTEORDER    1234
904 # elif defined(sparc)     || defined(__ppc__) || \
905        defined(__ARMEB__) || defined(__AARCH64EB__)
906 #   define SQLITE_BYTEORDER    4321
907 # else
908 #   define SQLITE_BYTEORDER 0
909 # endif
910 #endif
911 #if SQLITE_BYTEORDER==4321
912 # define SQLITE_BIGENDIAN    1
913 # define SQLITE_LITTLEENDIAN 0
914 # define SQLITE_UTF16NATIVE  SQLITE_UTF16BE
915 #elif SQLITE_BYTEORDER==1234
916 # define SQLITE_BIGENDIAN    0
917 # define SQLITE_LITTLEENDIAN 1
918 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
919 #else
920 # ifdef SQLITE_AMALGAMATION
921   const int sqlite3one = 1;
922 # else
923   extern const int sqlite3one;
924 # endif
925 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
926 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
927 # define SQLITE_UTF16NATIVE  (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
928 #endif
929 
930 /*
931 ** Constants for the largest and smallest possible 64-bit signed integers.
932 ** These macros are designed to work correctly on both 32-bit and 64-bit
933 ** compilers.
934 */
935 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
936 #define LARGEST_UINT64 (0xffffffff|(((u64)0xffffffff)<<32))
937 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
938 
939 /*
940 ** Round up a number to the next larger multiple of 8.  This is used
941 ** to force 8-byte alignment on 64-bit architectures.
942 **
943 ** ROUND8() always does the rounding, for any argument.
944 **
945 ** ROUND8P() assumes that the argument is already an integer number of
946 ** pointers in size, and so it is a no-op on systems where the pointer
947 ** size is 8.
948 */
949 #define ROUND8(x)     (((x)+7)&~7)
950 #if SQLITE_PTRSIZE==8
951 # define ROUND8P(x)   (x)
952 #else
953 # define ROUND8P(x)   (((x)+7)&~7)
954 #endif
955 
956 /*
957 ** Round down to the nearest multiple of 8
958 */
959 #define ROUNDDOWN8(x) ((x)&~7)
960 
961 /*
962 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
963 ** macro is used only within assert() to verify that the code gets
964 ** all alignment restrictions correct.
965 **
966 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
967 ** underlying malloc() implementation might return us 4-byte aligned
968 ** pointers.  In that case, only verify 4-byte alignment.
969 */
970 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
971 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
972 #else
973 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
974 #endif
975 
976 /*
977 ** Disable MMAP on platforms where it is known to not work
978 */
979 #if defined(__OpenBSD__) || defined(__QNXNTO__)
980 # undef SQLITE_MAX_MMAP_SIZE
981 # define SQLITE_MAX_MMAP_SIZE 0
982 #endif
983 
984 /*
985 ** Default maximum size of memory used by memory-mapped I/O in the VFS
986 */
987 #ifdef __APPLE__
988 # include <TargetConditionals.h>
989 #endif
990 #ifndef SQLITE_MAX_MMAP_SIZE
991 # if defined(__linux__) \
992   || defined(_WIN32) \
993   || (defined(__APPLE__) && defined(__MACH__)) \
994   || defined(__sun) \
995   || defined(__FreeBSD__) \
996   || defined(__DragonFly__)
997 #   define SQLITE_MAX_MMAP_SIZE 0x7fff0000  /* 2147418112 */
998 # else
999 #   define SQLITE_MAX_MMAP_SIZE 0
1000 # endif
1001 #endif
1002 
1003 /*
1004 ** The default MMAP_SIZE is zero on all platforms.  Or, even if a larger
1005 ** default MMAP_SIZE is specified at compile-time, make sure that it does
1006 ** not exceed the maximum mmap size.
1007 */
1008 #ifndef SQLITE_DEFAULT_MMAP_SIZE
1009 # define SQLITE_DEFAULT_MMAP_SIZE 0
1010 #endif
1011 #if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
1012 # undef SQLITE_DEFAULT_MMAP_SIZE
1013 # define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
1014 #endif
1015 
1016 /*
1017 ** TREETRACE_ENABLED will be either 1 or 0 depending on whether or not
1018 ** the Abstract Syntax Tree tracing logic is turned on.
1019 */
1020 #if !defined(SQLITE_AMALGAMATION)
1021 extern u32 sqlite3TreeTrace;
1022 #endif
1023 #if defined(SQLITE_DEBUG) \
1024     && (defined(SQLITE_TEST) || defined(SQLITE_ENABLE_SELECTTRACE) \
1025                              || defined(SQLITE_ENABLE_TREETRACE))
1026 # define TREETRACE_ENABLED 1
1027 # define SELECTTRACE(K,P,S,X)  \
1028   if(sqlite3TreeTrace&(K))   \
1029     sqlite3DebugPrintf("%u/%d/%p: ",(S)->selId,(P)->addrExplain,(S)),\
1030     sqlite3DebugPrintf X
1031 #else
1032 # define SELECTTRACE(K,P,S,X)
1033 # define TREETRACE_ENABLED 0
1034 #endif
1035 
1036 /*
1037 ** Macros for "wheretrace"
1038 */
1039 extern u32 sqlite3WhereTrace;
1040 #if defined(SQLITE_DEBUG) \
1041     && (defined(SQLITE_TEST) || defined(SQLITE_ENABLE_WHERETRACE))
1042 # define WHERETRACE(K,X)  if(sqlite3WhereTrace&(K)) sqlite3DebugPrintf X
1043 # define WHERETRACE_ENABLED 1
1044 #else
1045 # define WHERETRACE(K,X)
1046 #endif
1047 
1048 
1049 /*
1050 ** An instance of the following structure is used to store the busy-handler
1051 ** callback for a given sqlite handle.
1052 **
1053 ** The sqlite.busyHandler member of the sqlite struct contains the busy
1054 ** callback for the database handle. Each pager opened via the sqlite
1055 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
1056 ** callback is currently invoked only from within pager.c.
1057 */
1058 typedef struct BusyHandler BusyHandler;
1059 struct BusyHandler {
1060   int (*xBusyHandler)(void *,int);  /* The busy callback */
1061   void *pBusyArg;                   /* First arg to busy callback */
1062   int nBusy;                        /* Incremented with each busy call */
1063 };
1064 
1065 /*
1066 ** Name of table that holds the database schema.
1067 **
1068 ** The PREFERRED names are used whereever possible.  But LEGACY is also
1069 ** used for backwards compatibility.
1070 **
1071 **  1.  Queries can use either the PREFERRED or the LEGACY names
1072 **  2.  The sqlite3_set_authorizer() callback uses the LEGACY name
1073 **  3.  The PRAGMA table_list statement uses the PREFERRED name
1074 **
1075 ** The LEGACY names are stored in the internal symbol hash table
1076 ** in support of (2).  Names are translated using sqlite3PreferredTableName()
1077 ** for (3).  The sqlite3FindTable() function takes care of translating
1078 ** names for (1).
1079 **
1080 ** Note that "sqlite_temp_schema" can also be called "temp.sqlite_schema".
1081 */
1082 #define LEGACY_SCHEMA_TABLE          "sqlite_master"
1083 #define LEGACY_TEMP_SCHEMA_TABLE     "sqlite_temp_master"
1084 #define PREFERRED_SCHEMA_TABLE       "sqlite_schema"
1085 #define PREFERRED_TEMP_SCHEMA_TABLE  "sqlite_temp_schema"
1086 
1087 
1088 /*
1089 ** The root-page of the schema table.
1090 */
1091 #define SCHEMA_ROOT    1
1092 
1093 /*
1094 ** The name of the schema table.  The name is different for TEMP.
1095 */
1096 #define SCHEMA_TABLE(x) \
1097     ((!OMIT_TEMPDB)&&(x==1)?LEGACY_TEMP_SCHEMA_TABLE:LEGACY_SCHEMA_TABLE)
1098 
1099 /*
1100 ** A convenience macro that returns the number of elements in
1101 ** an array.
1102 */
1103 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
1104 
1105 /*
1106 ** Determine if the argument is a power of two
1107 */
1108 #define IsPowerOfTwo(X) (((X)&((X)-1))==0)
1109 
1110 /*
1111 ** The following value as a destructor means to use sqlite3DbFree().
1112 ** The sqlite3DbFree() routine requires two parameters instead of the
1113 ** one parameter that destructors normally want.  So we have to introduce
1114 ** this magic value that the code knows to handle differently.  Any
1115 ** pointer will work here as long as it is distinct from SQLITE_STATIC
1116 ** and SQLITE_TRANSIENT.
1117 */
1118 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3OomClear)
1119 
1120 /*
1121 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
1122 ** not support Writable Static Data (WSD) such as global and static variables.
1123 ** All variables must either be on the stack or dynamically allocated from
1124 ** the heap.  When WSD is unsupported, the variable declarations scattered
1125 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
1126 ** macro is used for this purpose.  And instead of referencing the variable
1127 ** directly, we use its constant as a key to lookup the run-time allocated
1128 ** buffer that holds real variable.  The constant is also the initializer
1129 ** for the run-time allocated buffer.
1130 **
1131 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
1132 ** macros become no-ops and have zero performance impact.
1133 */
1134 #ifdef SQLITE_OMIT_WSD
1135   #define SQLITE_WSD const
1136   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
1137   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
1138   int sqlite3_wsd_init(int N, int J);
1139   void *sqlite3_wsd_find(void *K, int L);
1140 #else
1141   #define SQLITE_WSD
1142   #define GLOBAL(t,v) v
1143   #define sqlite3GlobalConfig sqlite3Config
1144 #endif
1145 
1146 /*
1147 ** The following macros are used to suppress compiler warnings and to
1148 ** make it clear to human readers when a function parameter is deliberately
1149 ** left unused within the body of a function. This usually happens when
1150 ** a function is called via a function pointer. For example the
1151 ** implementation of an SQL aggregate step callback may not use the
1152 ** parameter indicating the number of arguments passed to the aggregate,
1153 ** if it knows that this is enforced elsewhere.
1154 **
1155 ** When a function parameter is not used at all within the body of a function,
1156 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
1157 ** However, these macros may also be used to suppress warnings related to
1158 ** parameters that may or may not be used depending on compilation options.
1159 ** For example those parameters only used in assert() statements. In these
1160 ** cases the parameters are named as per the usual conventions.
1161 */
1162 #define UNUSED_PARAMETER(x) (void)(x)
1163 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
1164 
1165 /*
1166 ** Forward references to structures
1167 */
1168 typedef struct AggInfo AggInfo;
1169 typedef struct AuthContext AuthContext;
1170 typedef struct AutoincInfo AutoincInfo;
1171 typedef struct Bitvec Bitvec;
1172 typedef struct CollSeq CollSeq;
1173 typedef struct Column Column;
1174 typedef struct Cte Cte;
1175 typedef struct CteUse CteUse;
1176 typedef struct Db Db;
1177 typedef struct DbFixer DbFixer;
1178 typedef struct Schema Schema;
1179 typedef struct Expr Expr;
1180 typedef struct ExprList ExprList;
1181 typedef struct FKey FKey;
1182 typedef struct FuncDestructor FuncDestructor;
1183 typedef struct FuncDef FuncDef;
1184 typedef struct FuncDefHash FuncDefHash;
1185 typedef struct IdList IdList;
1186 typedef struct Index Index;
1187 typedef struct IndexSample IndexSample;
1188 typedef struct KeyClass KeyClass;
1189 typedef struct KeyInfo KeyInfo;
1190 typedef struct Lookaside Lookaside;
1191 typedef struct LookasideSlot LookasideSlot;
1192 typedef struct Module Module;
1193 typedef struct NameContext NameContext;
1194 typedef struct OnOrUsing OnOrUsing;
1195 typedef struct Parse Parse;
1196 typedef struct ParseCleanup ParseCleanup;
1197 typedef struct PreUpdate PreUpdate;
1198 typedef struct PrintfArguments PrintfArguments;
1199 typedef struct RenameToken RenameToken;
1200 typedef struct Returning Returning;
1201 typedef struct RowSet RowSet;
1202 typedef struct Savepoint Savepoint;
1203 typedef struct Select Select;
1204 typedef struct SQLiteThread SQLiteThread;
1205 typedef struct SelectDest SelectDest;
1206 typedef struct SrcItem SrcItem;
1207 typedef struct SrcList SrcList;
1208 typedef struct sqlite3_str StrAccum; /* Internal alias for sqlite3_str */
1209 typedef struct Table Table;
1210 typedef struct TableLock TableLock;
1211 typedef struct Token Token;
1212 typedef struct TreeView TreeView;
1213 typedef struct Trigger Trigger;
1214 typedef struct TriggerPrg TriggerPrg;
1215 typedef struct TriggerStep TriggerStep;
1216 typedef struct UnpackedRecord UnpackedRecord;
1217 typedef struct Upsert Upsert;
1218 typedef struct VTable VTable;
1219 typedef struct VtabCtx VtabCtx;
1220 typedef struct Walker Walker;
1221 typedef struct WhereInfo WhereInfo;
1222 typedef struct Window Window;
1223 typedef struct With With;
1224 
1225 
1226 /*
1227 ** The bitmask datatype defined below is used for various optimizations.
1228 **
1229 ** Changing this from a 64-bit to a 32-bit type limits the number of
1230 ** tables in a join to 32 instead of 64.  But it also reduces the size
1231 ** of the library by 738 bytes on ix86.
1232 */
1233 #ifdef SQLITE_BITMASK_TYPE
1234   typedef SQLITE_BITMASK_TYPE Bitmask;
1235 #else
1236   typedef u64 Bitmask;
1237 #endif
1238 
1239 /*
1240 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
1241 */
1242 #define BMS  ((int)(sizeof(Bitmask)*8))
1243 
1244 /*
1245 ** A bit in a Bitmask
1246 */
1247 #define MASKBIT(n)    (((Bitmask)1)<<(n))
1248 #define MASKBIT64(n)  (((u64)1)<<(n))
1249 #define MASKBIT32(n)  (((unsigned int)1)<<(n))
1250 #define SMASKBIT32(n) ((n)<=31?((unsigned int)1)<<(n):0)
1251 #define ALLBITS       ((Bitmask)-1)
1252 
1253 /* A VList object records a mapping between parameters/variables/wildcards
1254 ** in the SQL statement (such as $abc, @pqr, or :xyz) and the integer
1255 ** variable number associated with that parameter.  See the format description
1256 ** on the sqlite3VListAdd() routine for more information.  A VList is really
1257 ** just an array of integers.
1258 */
1259 typedef int VList;
1260 
1261 /*
1262 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
1263 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
1264 ** pointer types (i.e. FuncDef) defined above.
1265 */
1266 #include "pager.h"
1267 #include "btree.h"
1268 #include "vdbe.h"
1269 #include "pcache.h"
1270 #include "os.h"
1271 #include "mutex.h"
1272 
1273 /* The SQLITE_EXTRA_DURABLE compile-time option used to set the default
1274 ** synchronous setting to EXTRA.  It is no longer supported.
1275 */
1276 #ifdef SQLITE_EXTRA_DURABLE
1277 # warning Use SQLITE_DEFAULT_SYNCHRONOUS=3 instead of SQLITE_EXTRA_DURABLE
1278 # define SQLITE_DEFAULT_SYNCHRONOUS 3
1279 #endif
1280 
1281 /*
1282 ** Default synchronous levels.
1283 **
1284 ** Note that (for historcal reasons) the PAGER_SYNCHRONOUS_* macros differ
1285 ** from the SQLITE_DEFAULT_SYNCHRONOUS value by 1.
1286 **
1287 **           PAGER_SYNCHRONOUS       DEFAULT_SYNCHRONOUS
1288 **   OFF           1                         0
1289 **   NORMAL        2                         1
1290 **   FULL          3                         2
1291 **   EXTRA         4                         3
1292 **
1293 ** The "PRAGMA synchronous" statement also uses the zero-based numbers.
1294 ** In other words, the zero-based numbers are used for all external interfaces
1295 ** and the one-based values are used internally.
1296 */
1297 #ifndef SQLITE_DEFAULT_SYNCHRONOUS
1298 # define SQLITE_DEFAULT_SYNCHRONOUS 2
1299 #endif
1300 #ifndef SQLITE_DEFAULT_WAL_SYNCHRONOUS
1301 # define SQLITE_DEFAULT_WAL_SYNCHRONOUS SQLITE_DEFAULT_SYNCHRONOUS
1302 #endif
1303 
1304 /*
1305 ** Each database file to be accessed by the system is an instance
1306 ** of the following structure.  There are normally two of these structures
1307 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
1308 ** aDb[1] is the database file used to hold temporary tables.  Additional
1309 ** databases may be attached.
1310 */
1311 struct Db {
1312   char *zDbSName;      /* Name of this database. (schema name, not filename) */
1313   Btree *pBt;          /* The B*Tree structure for this database file */
1314   u8 safety_level;     /* How aggressive at syncing data to disk */
1315   u8 bSyncSet;         /* True if "PRAGMA synchronous=N" has been run */
1316   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
1317 };
1318 
1319 /*
1320 ** An instance of the following structure stores a database schema.
1321 **
1322 ** Most Schema objects are associated with a Btree.  The exception is
1323 ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
1324 ** In shared cache mode, a single Schema object can be shared by multiple
1325 ** Btrees that refer to the same underlying BtShared object.
1326 **
1327 ** Schema objects are automatically deallocated when the last Btree that
1328 ** references them is destroyed.   The TEMP Schema is manually freed by
1329 ** sqlite3_close().
1330 *
1331 ** A thread must be holding a mutex on the corresponding Btree in order
1332 ** to access Schema content.  This implies that the thread must also be
1333 ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
1334 ** For a TEMP Schema, only the connection mutex is required.
1335 */
1336 struct Schema {
1337   int schema_cookie;   /* Database schema version number for this file */
1338   int iGeneration;     /* Generation counter.  Incremented with each change */
1339   Hash tblHash;        /* All tables indexed by name */
1340   Hash idxHash;        /* All (named) indices indexed by name */
1341   Hash trigHash;       /* All triggers indexed by name */
1342   Hash fkeyHash;       /* All foreign keys by referenced table name */
1343   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
1344   u8 file_format;      /* Schema format version for this file */
1345   u8 enc;              /* Text encoding used by this database */
1346   u16 schemaFlags;     /* Flags associated with this schema */
1347   int cache_size;      /* Number of pages to use in the cache */
1348 };
1349 
1350 /*
1351 ** These macros can be used to test, set, or clear bits in the
1352 ** Db.pSchema->flags field.
1353 */
1354 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))
1355 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->schemaFlags&(P))!=0)
1356 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->schemaFlags|=(P)
1357 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->schemaFlags&=~(P)
1358 
1359 /*
1360 ** Allowed values for the DB.pSchema->flags field.
1361 **
1362 ** The DB_SchemaLoaded flag is set after the database schema has been
1363 ** read into internal hash tables.
1364 **
1365 ** DB_UnresetViews means that one or more views have column names that
1366 ** have been filled out.  If the schema changes, these column names might
1367 ** changes and so the view will need to be reset.
1368 */
1369 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
1370 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
1371 #define DB_ResetWanted     0x0008  /* Reset the schema when nSchemaLock==0 */
1372 
1373 /*
1374 ** The number of different kinds of things that can be limited
1375 ** using the sqlite3_limit() interface.
1376 */
1377 #define SQLITE_N_LIMIT (SQLITE_LIMIT_WORKER_THREADS+1)
1378 
1379 /*
1380 ** Lookaside malloc is a set of fixed-size buffers that can be used
1381 ** to satisfy small transient memory allocation requests for objects
1382 ** associated with a particular database connection.  The use of
1383 ** lookaside malloc provides a significant performance enhancement
1384 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
1385 ** SQL statements.
1386 **
1387 ** The Lookaside structure holds configuration information about the
1388 ** lookaside malloc subsystem.  Each available memory allocation in
1389 ** the lookaside subsystem is stored on a linked list of LookasideSlot
1390 ** objects.
1391 **
1392 ** Lookaside allocations are only allowed for objects that are associated
1393 ** with a particular database connection.  Hence, schema information cannot
1394 ** be stored in lookaside because in shared cache mode the schema information
1395 ** is shared by multiple database connections.  Therefore, while parsing
1396 ** schema information, the Lookaside.bEnabled flag is cleared so that
1397 ** lookaside allocations are not used to construct the schema objects.
1398 **
1399 ** New lookaside allocations are only allowed if bDisable==0.  When
1400 ** bDisable is greater than zero, sz is set to zero which effectively
1401 ** disables lookaside without adding a new test for the bDisable flag
1402 ** in a performance-critical path.  sz should be set by to szTrue whenever
1403 ** bDisable changes back to zero.
1404 **
1405 ** Lookaside buffers are initially held on the pInit list.  As they are
1406 ** used and freed, they are added back to the pFree list.  New allocations
1407 ** come off of pFree first, then pInit as a fallback.  This dual-list
1408 ** allows use to compute a high-water mark - the maximum number of allocations
1409 ** outstanding at any point in the past - by subtracting the number of
1410 ** allocations on the pInit list from the total number of allocations.
1411 **
1412 ** Enhancement on 2019-12-12:  Two-size-lookaside
1413 ** The default lookaside configuration is 100 slots of 1200 bytes each.
1414 ** The larger slot sizes are important for performance, but they waste
1415 ** a lot of space, as most lookaside allocations are less than 128 bytes.
1416 ** The two-size-lookaside enhancement breaks up the lookaside allocation
1417 ** into two pools:  One of 128-byte slots and the other of the default size
1418 ** (1200-byte) slots.   Allocations are filled from the small-pool first,
1419 ** failing over to the full-size pool if that does not work.  Thus more
1420 ** lookaside slots are available while also using less memory.
1421 ** This enhancement can be omitted by compiling with
1422 ** SQLITE_OMIT_TWOSIZE_LOOKASIDE.
1423 */
1424 struct Lookaside {
1425   u32 bDisable;           /* Only operate the lookaside when zero */
1426   u16 sz;                 /* Size of each buffer in bytes */
1427   u16 szTrue;             /* True value of sz, even if disabled */
1428   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
1429   u32 nSlot;              /* Number of lookaside slots allocated */
1430   u32 anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
1431   LookasideSlot *pInit;   /* List of buffers not previously used */
1432   LookasideSlot *pFree;   /* List of available buffers */
1433 #ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
1434   LookasideSlot *pSmallInit; /* List of small buffers not prediously used */
1435   LookasideSlot *pSmallFree; /* List of available small buffers */
1436   void *pMiddle;          /* First byte past end of full-size buffers and
1437                           ** the first byte of LOOKASIDE_SMALL buffers */
1438 #endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
1439   void *pStart;           /* First byte of available memory space */
1440   void *pEnd;             /* First byte past end of available space */
1441 };
1442 struct LookasideSlot {
1443   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
1444 };
1445 
1446 #define DisableLookaside  db->lookaside.bDisable++;db->lookaside.sz=0
1447 #define EnableLookaside   db->lookaside.bDisable--;\
1448    db->lookaside.sz=db->lookaside.bDisable?0:db->lookaside.szTrue
1449 
1450 /* Size of the smaller allocations in two-size lookside */
1451 #ifdef SQLITE_OMIT_TWOSIZE_LOOKASIDE
1452 #  define LOOKASIDE_SMALL           0
1453 #else
1454 #  define LOOKASIDE_SMALL         128
1455 #endif
1456 
1457 /*
1458 ** A hash table for built-in function definitions.  (Application-defined
1459 ** functions use a regular table table from hash.h.)
1460 **
1461 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
1462 ** Collisions are on the FuncDef.u.pHash chain.  Use the SQLITE_FUNC_HASH()
1463 ** macro to compute a hash on the function name.
1464 */
1465 #define SQLITE_FUNC_HASH_SZ 23
1466 struct FuncDefHash {
1467   FuncDef *a[SQLITE_FUNC_HASH_SZ];       /* Hash table for functions */
1468 };
1469 #define SQLITE_FUNC_HASH(C,L) (((C)+(L))%SQLITE_FUNC_HASH_SZ)
1470 
1471 #ifdef SQLITE_USER_AUTHENTICATION
1472 /*
1473 ** Information held in the "sqlite3" database connection object and used
1474 ** to manage user authentication.
1475 */
1476 typedef struct sqlite3_userauth sqlite3_userauth;
1477 struct sqlite3_userauth {
1478   u8 authLevel;                 /* Current authentication level */
1479   int nAuthPW;                  /* Size of the zAuthPW in bytes */
1480   char *zAuthPW;                /* Password used to authenticate */
1481   char *zAuthUser;              /* User name used to authenticate */
1482 };
1483 
1484 /* Allowed values for sqlite3_userauth.authLevel */
1485 #define UAUTH_Unknown     0     /* Authentication not yet checked */
1486 #define UAUTH_Fail        1     /* User authentication failed */
1487 #define UAUTH_User        2     /* Authenticated as a normal user */
1488 #define UAUTH_Admin       3     /* Authenticated as an administrator */
1489 
1490 /* Functions used only by user authorization logic */
1491 int sqlite3UserAuthTable(const char*);
1492 int sqlite3UserAuthCheckLogin(sqlite3*,const char*,u8*);
1493 void sqlite3UserAuthInit(sqlite3*);
1494 void sqlite3CryptFunc(sqlite3_context*,int,sqlite3_value**);
1495 
1496 #endif /* SQLITE_USER_AUTHENTICATION */
1497 
1498 /*
1499 ** typedef for the authorization callback function.
1500 */
1501 #ifdef SQLITE_USER_AUTHENTICATION
1502   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1503                                const char*, const char*);
1504 #else
1505   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1506                                const char*);
1507 #endif
1508 
1509 #ifndef SQLITE_OMIT_DEPRECATED
1510 /* This is an extra SQLITE_TRACE macro that indicates "legacy" tracing
1511 ** in the style of sqlite3_trace()
1512 */
1513 #define SQLITE_TRACE_LEGACY          0x40     /* Use the legacy xTrace */
1514 #define SQLITE_TRACE_XPROFILE        0x80     /* Use the legacy xProfile */
1515 #else
1516 #define SQLITE_TRACE_LEGACY          0
1517 #define SQLITE_TRACE_XPROFILE        0
1518 #endif /* SQLITE_OMIT_DEPRECATED */
1519 #define SQLITE_TRACE_NONLEGACY_MASK  0x0f     /* Normal flags */
1520 
1521 /*
1522 ** Maximum number of sqlite3.aDb[] entries.  This is the number of attached
1523 ** databases plus 2 for "main" and "temp".
1524 */
1525 #define SQLITE_MAX_DB (SQLITE_MAX_ATTACHED+2)
1526 
1527 /*
1528 ** Each database connection is an instance of the following structure.
1529 */
1530 struct sqlite3 {
1531   sqlite3_vfs *pVfs;            /* OS Interface */
1532   struct Vdbe *pVdbe;           /* List of active virtual machines */
1533   CollSeq *pDfltColl;           /* BINARY collseq for the database encoding */
1534   sqlite3_mutex *mutex;         /* Connection mutex */
1535   Db *aDb;                      /* All backends */
1536   int nDb;                      /* Number of backends currently in use */
1537   u32 mDbFlags;                 /* flags recording internal state */
1538   u64 flags;                    /* flags settable by pragmas. See below */
1539   i64 lastRowid;                /* ROWID of most recent insert (see above) */
1540   i64 szMmap;                   /* Default mmap_size setting */
1541   u32 nSchemaLock;              /* Do not reset the schema when non-zero */
1542   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
1543   int errCode;                  /* Most recent error code (SQLITE_*) */
1544   int errByteOffset;            /* Byte offset of error in SQL statement */
1545   int errMask;                  /* & result codes with this before returning */
1546   int iSysErrno;                /* Errno value from last system error */
1547   u32 dbOptFlags;               /* Flags to enable/disable optimizations */
1548   u8 enc;                       /* Text encoding */
1549   u8 autoCommit;                /* The auto-commit flag. */
1550   u8 temp_store;                /* 1: file 2: memory 0: default */
1551   u8 mallocFailed;              /* True if we have seen a malloc failure */
1552   u8 bBenignMalloc;             /* Do not require OOMs if true */
1553   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
1554   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
1555   u8 suppressErr;               /* Do not issue error messages if true */
1556   u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
1557   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
1558   u8 mTrace;                    /* zero or more SQLITE_TRACE flags */
1559   u8 noSharedCache;             /* True if no shared-cache backends */
1560   u8 nSqlExec;                  /* Number of pending OP_SqlExec opcodes */
1561   u8 eOpenState;                /* Current condition of the connection */
1562   int nextPagesize;             /* Pagesize after VACUUM if >0 */
1563   i64 nChange;                  /* Value returned by sqlite3_changes() */
1564   i64 nTotalChange;             /* Value returned by sqlite3_total_changes() */
1565   int aLimit[SQLITE_N_LIMIT];   /* Limits */
1566   int nMaxSorterMmap;           /* Maximum size of regions mapped by sorter */
1567   struct sqlite3InitInfo {      /* Information used during initialization */
1568     Pgno newTnum;               /* Rootpage of table being initialized */
1569     u8 iDb;                     /* Which db file is being initialized */
1570     u8 busy;                    /* TRUE if currently initializing */
1571     unsigned orphanTrigger : 1; /* Last statement is orphaned TEMP trigger */
1572     unsigned imposterTable : 1; /* Building an imposter table */
1573     unsigned reopenMemdb : 1;   /* ATTACH is really a reopen using MemDB */
1574     const char **azInit;        /* "type", "name", and "tbl_name" columns */
1575   } init;
1576   int nVdbeActive;              /* Number of VDBEs currently running */
1577   int nVdbeRead;                /* Number of active VDBEs that read or write */
1578   int nVdbeWrite;               /* Number of active VDBEs that read and write */
1579   int nVdbeExec;                /* Number of nested calls to VdbeExec() */
1580   int nVDestroy;                /* Number of active OP_VDestroy operations */
1581   int nExtension;               /* Number of loaded extensions */
1582   void **aExtension;            /* Array of shared library handles */
1583   union {
1584     void (*xLegacy)(void*,const char*);   /* mTrace==SQLITE_TRACE_LEGACY */
1585     int (*xV2)(u32,void*,void*,void*);    /* All other mTrace values */
1586   } trace;
1587   void *pTraceArg;                        /* Argument to the trace function */
1588 #ifndef SQLITE_OMIT_DEPRECATED
1589   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
1590   void *pProfileArg;                        /* Argument to profile function */
1591 #endif
1592   void *pCommitArg;                 /* Argument to xCommitCallback() */
1593   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
1594   void *pRollbackArg;               /* Argument to xRollbackCallback() */
1595   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
1596   void *pUpdateArg;
1597   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
1598   void *pAutovacPagesArg;           /* Client argument to autovac_pages */
1599   void (*xAutovacDestr)(void*);     /* Destructor for pAutovacPAgesArg */
1600   unsigned int (*xAutovacPages)(void*,const char*,u32,u32,u32);
1601   Parse *pParse;                /* Current parse */
1602 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
1603   void *pPreUpdateArg;          /* First argument to xPreUpdateCallback */
1604   void (*xPreUpdateCallback)(   /* Registered using sqlite3_preupdate_hook() */
1605     void*,sqlite3*,int,char const*,char const*,sqlite3_int64,sqlite3_int64
1606   );
1607   PreUpdate *pPreUpdate;        /* Context for active pre-update callback */
1608 #endif /* SQLITE_ENABLE_PREUPDATE_HOOK */
1609 #ifndef SQLITE_OMIT_WAL
1610   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
1611   void *pWalArg;
1612 #endif
1613   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
1614   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
1615   void *pCollNeededArg;
1616   sqlite3_value *pErr;          /* Most recent error message */
1617   union {
1618     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
1619     double notUsed1;            /* Spacer */
1620   } u1;
1621   Lookaside lookaside;          /* Lookaside malloc configuration */
1622 #ifndef SQLITE_OMIT_AUTHORIZATION
1623   sqlite3_xauth xAuth;          /* Access authorization function */
1624   void *pAuthArg;               /* 1st argument to the access auth function */
1625 #endif
1626 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
1627   int (*xProgress)(void *);     /* The progress callback */
1628   void *pProgressArg;           /* Argument to the progress callback */
1629   unsigned nProgressOps;        /* Number of opcodes for progress callback */
1630 #endif
1631 #ifndef SQLITE_OMIT_VIRTUALTABLE
1632   int nVTrans;                  /* Allocated size of aVTrans */
1633   Hash aModule;                 /* populated by sqlite3_create_module() */
1634   VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
1635   VTable **aVTrans;             /* Virtual tables with open transactions */
1636   VTable *pDisconnect;          /* Disconnect these in next sqlite3_prepare() */
1637 #endif
1638   Hash aFunc;                   /* Hash table of connection functions */
1639   Hash aCollSeq;                /* All collating sequences */
1640   BusyHandler busyHandler;      /* Busy callback */
1641   Db aDbStatic[2];              /* Static space for the 2 default backends */
1642   Savepoint *pSavepoint;        /* List of active savepoints */
1643   int nAnalysisLimit;           /* Number of index rows to ANALYZE */
1644   int busyTimeout;              /* Busy handler timeout, in msec */
1645   int nSavepoint;               /* Number of non-transaction savepoints */
1646   int nStatement;               /* Number of nested statement-transactions  */
1647   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
1648   i64 nDeferredImmCons;         /* Net deferred immediate constraints */
1649   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
1650 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
1651   /* The following variables are all protected by the STATIC_MAIN
1652   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
1653   **
1654   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
1655   ** unlock so that it can proceed.
1656   **
1657   ** When X.pBlockingConnection==Y, that means that something that X tried
1658   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
1659   ** held by Y.
1660   */
1661   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
1662   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
1663   void *pUnlockArg;                     /* Argument to xUnlockNotify */
1664   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
1665   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
1666 #endif
1667 #ifdef SQLITE_USER_AUTHENTICATION
1668   sqlite3_userauth auth;        /* User authentication information */
1669 #endif
1670 };
1671 
1672 /*
1673 ** A macro to discover the encoding of a database.
1674 */
1675 #define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
1676 #define ENC(db)        ((db)->enc)
1677 
1678 /*
1679 ** A u64 constant where the lower 32 bits are all zeros.  Only the
1680 ** upper 32 bits are included in the argument.  Necessary because some
1681 ** C-compilers still do not accept LL integer literals.
1682 */
1683 #define HI(X)  ((u64)(X)<<32)
1684 
1685 /*
1686 ** Possible values for the sqlite3.flags.
1687 **
1688 ** Value constraints (enforced via assert()):
1689 **      SQLITE_FullFSync     == PAGER_FULLFSYNC
1690 **      SQLITE_CkptFullFSync == PAGER_CKPT_FULLFSYNC
1691 **      SQLITE_CacheSpill    == PAGER_CACHE_SPILL
1692 */
1693 #define SQLITE_WriteSchema    0x00000001  /* OK to update SQLITE_SCHEMA */
1694 #define SQLITE_LegacyFileFmt  0x00000002  /* Create new databases in format 1 */
1695 #define SQLITE_FullColNames   0x00000004  /* Show full column names on SELECT */
1696 #define SQLITE_FullFSync      0x00000008  /* Use full fsync on the backend */
1697 #define SQLITE_CkptFullFSync  0x00000010  /* Use full fsync for checkpoint */
1698 #define SQLITE_CacheSpill     0x00000020  /* OK to spill pager cache */
1699 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
1700 #define SQLITE_TrustedSchema  0x00000080  /* Allow unsafe functions and
1701                                           ** vtabs in the schema definition */
1702 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
1703                                           /*   result set is empty */
1704 #define SQLITE_IgnoreChecks   0x00000200  /* Do not enforce check constraints */
1705 #define SQLITE_ReadUncommit   0x00000400  /* READ UNCOMMITTED in shared-cache */
1706 #define SQLITE_NoCkptOnClose  0x00000800  /* No checkpoint on close()/DETACH */
1707 #define SQLITE_ReverseOrder   0x00001000  /* Reverse unordered SELECTs */
1708 #define SQLITE_RecTriggers    0x00002000  /* Enable recursive triggers */
1709 #define SQLITE_ForeignKeys    0x00004000  /* Enforce foreign key constraints  */
1710 #define SQLITE_AutoIndex      0x00008000  /* Enable automatic indexes */
1711 #define SQLITE_LoadExtension  0x00010000  /* Enable load_extension */
1712 #define SQLITE_LoadExtFunc    0x00020000  /* Enable load_extension() SQL func */
1713 #define SQLITE_EnableTrigger  0x00040000  /* True to enable triggers */
1714 #define SQLITE_DeferFKs       0x00080000  /* Defer all FK constraints */
1715 #define SQLITE_QueryOnly      0x00100000  /* Disable database changes */
1716 #define SQLITE_CellSizeCk     0x00200000  /* Check btree cell sizes on load */
1717 #define SQLITE_Fts3Tokenizer  0x00400000  /* Enable fts3_tokenizer(2) */
1718 #define SQLITE_EnableQPSG     0x00800000  /* Query Planner Stability Guarantee*/
1719 #define SQLITE_TriggerEQP     0x01000000  /* Show trigger EXPLAIN QUERY PLAN */
1720 #define SQLITE_ResetDatabase  0x02000000  /* Reset the database */
1721 #define SQLITE_LegacyAlter    0x04000000  /* Legacy ALTER TABLE behaviour */
1722 #define SQLITE_NoSchemaError  0x08000000  /* Do not report schema parse errors*/
1723 #define SQLITE_Defensive      0x10000000  /* Input SQL is likely hostile */
1724 #define SQLITE_DqsDDL         0x20000000  /* dbl-quoted strings allowed in DDL*/
1725 #define SQLITE_DqsDML         0x40000000  /* dbl-quoted strings allowed in DML*/
1726 #define SQLITE_EnableView     0x80000000  /* Enable the use of views */
1727 #define SQLITE_CountRows      HI(0x00001) /* Count rows changed by INSERT, */
1728                                           /*   DELETE, or UPDATE and return */
1729                                           /*   the count using a callback. */
1730 #define SQLITE_CorruptRdOnly  HI(0x00002) /* Prohibit writes due to error */
1731 
1732 /* Flags used only if debugging */
1733 #ifdef SQLITE_DEBUG
1734 #define SQLITE_SqlTrace       HI(0x0100000) /* Debug print SQL as it executes */
1735 #define SQLITE_VdbeListing    HI(0x0200000) /* Debug listings of VDBE progs */
1736 #define SQLITE_VdbeTrace      HI(0x0400000) /* True to trace VDBE execution */
1737 #define SQLITE_VdbeAddopTrace HI(0x0800000) /* Trace sqlite3VdbeAddOp() calls */
1738 #define SQLITE_VdbeEQP        HI(0x1000000) /* Debug EXPLAIN QUERY PLAN */
1739 #define SQLITE_ParserTrace    HI(0x2000000) /* PRAGMA parser_trace=ON */
1740 #endif
1741 
1742 /*
1743 ** Allowed values for sqlite3.mDbFlags
1744 */
1745 #define DBFLAG_SchemaChange   0x0001  /* Uncommitted Hash table changes */
1746 #define DBFLAG_PreferBuiltin  0x0002  /* Preference to built-in funcs */
1747 #define DBFLAG_Vacuum         0x0004  /* Currently in a VACUUM */
1748 #define DBFLAG_VacuumInto     0x0008  /* Currently running VACUUM INTO */
1749 #define DBFLAG_SchemaKnownOk  0x0010  /* Schema is known to be valid */
1750 #define DBFLAG_InternalFunc   0x0020  /* Allow use of internal functions */
1751 #define DBFLAG_EncodingFixed  0x0040  /* No longer possible to change enc. */
1752 
1753 /*
1754 ** Bits of the sqlite3.dbOptFlags field that are used by the
1755 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
1756 ** selectively disable various optimizations.
1757 */
1758 #define SQLITE_QueryFlattener 0x00000001 /* Query flattening */
1759 #define SQLITE_WindowFunc     0x00000002 /* Use xInverse for window functions */
1760 #define SQLITE_GroupByOrder   0x00000004 /* GROUPBY cover of ORDERBY */
1761 #define SQLITE_FactorOutConst 0x00000008 /* Constant factoring */
1762 #define SQLITE_DistinctOpt    0x00000010 /* DISTINCT using indexes */
1763 #define SQLITE_CoverIdxScan   0x00000020 /* Covering index scans */
1764 #define SQLITE_OrderByIdxJoin 0x00000040 /* ORDER BY of joins via index */
1765 #define SQLITE_Transitive     0x00000080 /* Transitive constraints */
1766 #define SQLITE_OmitNoopJoin   0x00000100 /* Omit unused tables in joins */
1767 #define SQLITE_CountOfView    0x00000200 /* The count-of-view optimization */
1768 #define SQLITE_CursorHints    0x00000400 /* Add OP_CursorHint opcodes */
1769 #define SQLITE_Stat4          0x00000800 /* Use STAT4 data */
1770    /* TH3 expects this value  ^^^^^^^^^^ to be 0x0000800. Don't change it */
1771 #define SQLITE_PushDown       0x00001000 /* The push-down optimization */
1772 #define SQLITE_SimplifyJoin   0x00002000 /* Convert LEFT JOIN to JOIN */
1773 #define SQLITE_SkipScan       0x00004000 /* Skip-scans */
1774 #define SQLITE_PropagateConst 0x00008000 /* The constant propagation opt */
1775 #define SQLITE_MinMaxOpt      0x00010000 /* The min/max optimization */
1776 #define SQLITE_SeekScan       0x00020000 /* The OP_SeekScan optimization */
1777 #define SQLITE_OmitOrderBy    0x00040000 /* Omit pointless ORDER BY */
1778    /* TH3 expects this value  ^^^^^^^^^^ to be 0x40000. Coordinate any change */
1779 #define SQLITE_BloomFilter    0x00080000 /* Use a Bloom filter on searches */
1780 #define SQLITE_BloomPulldown  0x00100000 /* Run Bloom filters early */
1781 #define SQLITE_BalancedMerge  0x00200000 /* Balance multi-way merges */
1782 #define SQLITE_ReleaseReg     0x00400000 /* Use OP_ReleaseReg for testing */
1783 #define SQLITE_FlttnUnionAll  0x00800000 /* Disable the UNION ALL flattener */
1784 #define SQLITE_AllOpts        0xffffffff /* All optimizations */
1785 
1786 /*
1787 ** Macros for testing whether or not optimizations are enabled or disabled.
1788 */
1789 #define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
1790 #define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
1791 
1792 /*
1793 ** Return true if it OK to factor constant expressions into the initialization
1794 ** code. The argument is a Parse object for the code generator.
1795 */
1796 #define ConstFactorOk(P) ((P)->okConstFactor)
1797 
1798 /* Possible values for the sqlite3.eOpenState field.
1799 ** The numbers are randomly selected such that a minimum of three bits must
1800 ** change to convert any number to another or to zero
1801 */
1802 #define SQLITE_STATE_OPEN     0x76  /* Database is open */
1803 #define SQLITE_STATE_CLOSED   0xce  /* Database is closed */
1804 #define SQLITE_STATE_SICK     0xba  /* Error and awaiting close */
1805 #define SQLITE_STATE_BUSY     0x6d  /* Database currently in use */
1806 #define SQLITE_STATE_ERROR    0xd5  /* An SQLITE_MISUSE error occurred */
1807 #define SQLITE_STATE_ZOMBIE   0xa7  /* Close with last statement close */
1808 
1809 /*
1810 ** Each SQL function is defined by an instance of the following
1811 ** structure.  For global built-in functions (ex: substr(), max(), count())
1812 ** a pointer to this structure is held in the sqlite3BuiltinFunctions object.
1813 ** For per-connection application-defined functions, a pointer to this
1814 ** structure is held in the db->aHash hash table.
1815 **
1816 ** The u.pHash field is used by the global built-ins.  The u.pDestructor
1817 ** field is used by per-connection app-def functions.
1818 */
1819 struct FuncDef {
1820   i8 nArg;             /* Number of arguments.  -1 means unlimited */
1821   u32 funcFlags;       /* Some combination of SQLITE_FUNC_* */
1822   void *pUserData;     /* User data parameter */
1823   FuncDef *pNext;      /* Next function with same name */
1824   void (*xSFunc)(sqlite3_context*,int,sqlite3_value**); /* func or agg-step */
1825   void (*xFinalize)(sqlite3_context*);                  /* Agg finalizer */
1826   void (*xValue)(sqlite3_context*);                     /* Current agg value */
1827   void (*xInverse)(sqlite3_context*,int,sqlite3_value**); /* inverse agg-step */
1828   const char *zName;   /* SQL name of the function. */
1829   union {
1830     FuncDef *pHash;      /* Next with a different name but the same hash */
1831     FuncDestructor *pDestructor;   /* Reference counted destructor function */
1832   } u; /* pHash if SQLITE_FUNC_BUILTIN, pDestructor otherwise */
1833 };
1834 
1835 /*
1836 ** This structure encapsulates a user-function destructor callback (as
1837 ** configured using create_function_v2()) and a reference counter. When
1838 ** create_function_v2() is called to create a function with a destructor,
1839 ** a single object of this type is allocated. FuncDestructor.nRef is set to
1840 ** the number of FuncDef objects created (either 1 or 3, depending on whether
1841 ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
1842 ** member of each of the new FuncDef objects is set to point to the allocated
1843 ** FuncDestructor.
1844 **
1845 ** Thereafter, when one of the FuncDef objects is deleted, the reference
1846 ** count on this object is decremented. When it reaches 0, the destructor
1847 ** is invoked and the FuncDestructor structure freed.
1848 */
1849 struct FuncDestructor {
1850   int nRef;
1851   void (*xDestroy)(void *);
1852   void *pUserData;
1853 };
1854 
1855 /*
1856 ** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
1857 ** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  And
1858 ** SQLITE_FUNC_CONSTANT must be the same as SQLITE_DETERMINISTIC.  There
1859 ** are assert() statements in the code to verify this.
1860 **
1861 ** Value constraints (enforced via assert()):
1862 **     SQLITE_FUNC_MINMAX      ==  NC_MinMaxAgg      == SF_MinMaxAgg
1863 **     SQLITE_FUNC_ANYORDER    ==  NC_OrderAgg       == SF_OrderByReqd
1864 **     SQLITE_FUNC_LENGTH      ==  OPFLAG_LENGTHARG
1865 **     SQLITE_FUNC_TYPEOF      ==  OPFLAG_TYPEOFARG
1866 **     SQLITE_FUNC_CONSTANT    ==  SQLITE_DETERMINISTIC from the API
1867 **     SQLITE_FUNC_DIRECT      ==  SQLITE_DIRECTONLY from the API
1868 **     SQLITE_FUNC_UNSAFE      ==  SQLITE_INNOCUOUS
1869 **     SQLITE_FUNC_ENCMASK   depends on SQLITE_UTF* macros in the API
1870 */
1871 #define SQLITE_FUNC_ENCMASK  0x0003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
1872 #define SQLITE_FUNC_LIKE     0x0004 /* Candidate for the LIKE optimization */
1873 #define SQLITE_FUNC_CASE     0x0008 /* Case-sensitive LIKE-type function */
1874 #define SQLITE_FUNC_EPHEM    0x0010 /* Ephemeral.  Delete with VDBE */
1875 #define SQLITE_FUNC_NEEDCOLL 0x0020 /* sqlite3GetFuncCollSeq() might be called*/
1876 #define SQLITE_FUNC_LENGTH   0x0040 /* Built-in length() function */
1877 #define SQLITE_FUNC_TYPEOF   0x0080 /* Built-in typeof() function */
1878 #define SQLITE_FUNC_COUNT    0x0100 /* Built-in count(*) aggregate */
1879 /*                           0x0200 -- available for reuse */
1880 #define SQLITE_FUNC_UNLIKELY 0x0400 /* Built-in unlikely() function */
1881 #define SQLITE_FUNC_CONSTANT 0x0800 /* Constant inputs give a constant output */
1882 #define SQLITE_FUNC_MINMAX   0x1000 /* True for min() and max() aggregates */
1883 #define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
1884                                     ** single query - might change over time */
1885 #define SQLITE_FUNC_TEST     0x4000 /* Built-in testing functions */
1886 #define SQLITE_FUNC_OFFSET   0x8000 /* Built-in sqlite_offset() function */
1887 #define SQLITE_FUNC_WINDOW   0x00010000 /* Built-in window-only function */
1888 #define SQLITE_FUNC_INTERNAL 0x00040000 /* For use by NestedParse() only */
1889 #define SQLITE_FUNC_DIRECT   0x00080000 /* Not for use in TRIGGERs or VIEWs */
1890 #define SQLITE_FUNC_SUBTYPE  0x00100000 /* Result likely to have sub-type */
1891 #define SQLITE_FUNC_UNSAFE   0x00200000 /* Function has side effects */
1892 #define SQLITE_FUNC_INLINE   0x00400000 /* Functions implemented in-line */
1893 #define SQLITE_FUNC_BUILTIN  0x00800000 /* This is a built-in function */
1894 #define SQLITE_FUNC_ANYORDER 0x08000000 /* count/min/max aggregate */
1895 
1896 /* Identifier numbers for each in-line function */
1897 #define INLINEFUNC_coalesce             0
1898 #define INLINEFUNC_implies_nonnull_row  1
1899 #define INLINEFUNC_expr_implies_expr    2
1900 #define INLINEFUNC_expr_compare         3
1901 #define INLINEFUNC_affinity             4
1902 #define INLINEFUNC_iif                  5
1903 #define INLINEFUNC_unlikely            99  /* Default case */
1904 
1905 /*
1906 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
1907 ** used to create the initializers for the FuncDef structures.
1908 **
1909 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
1910 **     Used to create a scalar function definition of a function zName
1911 **     implemented by C function xFunc that accepts nArg arguments. The
1912 **     value passed as iArg is cast to a (void*) and made available
1913 **     as the user-data (sqlite3_user_data()) for the function. If
1914 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
1915 **
1916 **   VFUNCTION(zName, nArg, iArg, bNC, xFunc)
1917 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
1918 **
1919 **   SFUNCTION(zName, nArg, iArg, bNC, xFunc)
1920 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
1921 **     adds the SQLITE_DIRECTONLY flag.
1922 **
1923 **   INLINE_FUNC(zName, nArg, iFuncId, mFlags)
1924 **     zName is the name of a function that is implemented by in-line
1925 **     byte code rather than by the usual callbacks. The iFuncId
1926 **     parameter determines the function id.  The mFlags parameter is
1927 **     optional SQLITE_FUNC_ flags for this function.
1928 **
1929 **   TEST_FUNC(zName, nArg, iFuncId, mFlags)
1930 **     zName is the name of a test-only function implemented by in-line
1931 **     byte code rather than by the usual callbacks. The iFuncId
1932 **     parameter determines the function id.  The mFlags parameter is
1933 **     optional SQLITE_FUNC_ flags for this function.
1934 **
1935 **   DFUNCTION(zName, nArg, iArg, bNC, xFunc)
1936 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
1937 **     adds the SQLITE_FUNC_SLOCHNG flag.  Used for date & time functions
1938 **     and functions like sqlite_version() that can change, but not during
1939 **     a single query.  The iArg is ignored.  The user-data is always set
1940 **     to a NULL pointer.  The bNC parameter is not used.
1941 **
1942 **   MFUNCTION(zName, nArg, xPtr, xFunc)
1943 **     For math-library functions.  xPtr is an arbitrary pointer.
1944 **
1945 **   PURE_DATE(zName, nArg, iArg, bNC, xFunc)
1946 **     Used for "pure" date/time functions, this macro is like DFUNCTION
1947 **     except that it does set the SQLITE_FUNC_CONSTANT flags.  iArg is
1948 **     ignored and the user-data for these functions is set to an
1949 **     arbitrary non-NULL pointer.  The bNC parameter is not used.
1950 **
1951 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
1952 **     Used to create an aggregate function definition implemented by
1953 **     the C functions xStep and xFinal. The first four parameters
1954 **     are interpreted in the same way as the first 4 parameters to
1955 **     FUNCTION().
1956 **
1957 **   WAGGREGATE(zName, nArg, iArg, xStep, xFinal, xValue, xInverse)
1958 **     Used to create an aggregate function definition implemented by
1959 **     the C functions xStep and xFinal. The first four parameters
1960 **     are interpreted in the same way as the first 4 parameters to
1961 **     FUNCTION().
1962 **
1963 **   LIKEFUNC(zName, nArg, pArg, flags)
1964 **     Used to create a scalar function definition of a function zName
1965 **     that accepts nArg arguments and is implemented by a call to C
1966 **     function likeFunc. Argument pArg is cast to a (void *) and made
1967 **     available as the function user-data (sqlite3_user_data()). The
1968 **     FuncDef.flags variable is set to the value passed as the flags
1969 **     parameter.
1970 */
1971 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1972   {nArg, SQLITE_FUNC_BUILTIN|\
1973    SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1974    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
1975 #define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1976   {nArg, SQLITE_FUNC_BUILTIN|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1977    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
1978 #define SFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1979   {nArg, SQLITE_FUNC_BUILTIN|SQLITE_UTF8|SQLITE_DIRECTONLY|SQLITE_FUNC_UNSAFE, \
1980    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
1981 #define MFUNCTION(zName, nArg, xPtr, xFunc) \
1982   {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
1983    xPtr, 0, xFunc, 0, 0, 0, #zName, {0} }
1984 #define JFUNCTION(zName, nArg, iArg, xFunc) \
1985   {nArg, SQLITE_FUNC_BUILTIN|SQLITE_DETERMINISTIC|SQLITE_INNOCUOUS|\
1986    SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
1987    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
1988 #define INLINE_FUNC(zName, nArg, iArg, mFlags) \
1989   {nArg, SQLITE_FUNC_BUILTIN|\
1990    SQLITE_UTF8|SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
1991    SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
1992 #define TEST_FUNC(zName, nArg, iArg, mFlags) \
1993   {nArg, SQLITE_FUNC_BUILTIN|\
1994          SQLITE_UTF8|SQLITE_FUNC_INTERNAL|SQLITE_FUNC_TEST| \
1995          SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
1996    SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
1997 #define DFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1998   {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_SLOCHNG|SQLITE_UTF8, \
1999    0, 0, xFunc, 0, 0, 0, #zName, {0} }
2000 #define PURE_DATE(zName, nArg, iArg, bNC, xFunc) \
2001   {nArg, SQLITE_FUNC_BUILTIN|\
2002          SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|SQLITE_FUNC_CONSTANT, \
2003    (void*)&sqlite3Config, 0, xFunc, 0, 0, 0, #zName, {0} }
2004 #define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
2005   {nArg, SQLITE_FUNC_BUILTIN|\
2006    SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
2007    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
2008 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
2009   {nArg, SQLITE_FUNC_BUILTIN|\
2010    SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
2011    pArg, 0, xFunc, 0, 0, 0, #zName, }
2012 #define LIKEFUNC(zName, nArg, arg, flags) \
2013   {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
2014    (void *)arg, 0, likeFunc, 0, 0, 0, #zName, {0} }
2015 #define WAGGREGATE(zName, nArg, arg, nc, xStep, xFinal, xValue, xInverse, f) \
2016   {nArg, SQLITE_FUNC_BUILTIN|SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|f, \
2017    SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,xValue,xInverse,#zName, {0}}
2018 #define INTERNAL_FUNCTION(zName, nArg, xFunc) \
2019   {nArg, SQLITE_FUNC_BUILTIN|\
2020    SQLITE_FUNC_INTERNAL|SQLITE_UTF8|SQLITE_FUNC_CONSTANT, \
2021    0, 0, xFunc, 0, 0, 0, #zName, {0} }
2022 
2023 
2024 /*
2025 ** All current savepoints are stored in a linked list starting at
2026 ** sqlite3.pSavepoint. The first element in the list is the most recently
2027 ** opened savepoint. Savepoints are added to the list by the vdbe
2028 ** OP_Savepoint instruction.
2029 */
2030 struct Savepoint {
2031   char *zName;                        /* Savepoint name (nul-terminated) */
2032   i64 nDeferredCons;                  /* Number of deferred fk violations */
2033   i64 nDeferredImmCons;               /* Number of deferred imm fk. */
2034   Savepoint *pNext;                   /* Parent savepoint (if any) */
2035 };
2036 
2037 /*
2038 ** The following are used as the second parameter to sqlite3Savepoint(),
2039 ** and as the P1 argument to the OP_Savepoint instruction.
2040 */
2041 #define SAVEPOINT_BEGIN      0
2042 #define SAVEPOINT_RELEASE    1
2043 #define SAVEPOINT_ROLLBACK   2
2044 
2045 
2046 /*
2047 ** Each SQLite module (virtual table definition) is defined by an
2048 ** instance of the following structure, stored in the sqlite3.aModule
2049 ** hash table.
2050 */
2051 struct Module {
2052   const sqlite3_module *pModule;       /* Callback pointers */
2053   const char *zName;                   /* Name passed to create_module() */
2054   int nRefModule;                      /* Number of pointers to this object */
2055   void *pAux;                          /* pAux passed to create_module() */
2056   void (*xDestroy)(void *);            /* Module destructor function */
2057   Table *pEpoTab;                      /* Eponymous table for this module */
2058 };
2059 
2060 /*
2061 ** Information about each column of an SQL table is held in an instance
2062 ** of the Column structure, in the Table.aCol[] array.
2063 **
2064 ** Definitions:
2065 **
2066 **   "table column index"     This is the index of the column in the
2067 **                            Table.aCol[] array, and also the index of
2068 **                            the column in the original CREATE TABLE stmt.
2069 **
2070 **   "storage column index"   This is the index of the column in the
2071 **                            record BLOB generated by the OP_MakeRecord
2072 **                            opcode.  The storage column index is less than
2073 **                            or equal to the table column index.  It is
2074 **                            equal if and only if there are no VIRTUAL
2075 **                            columns to the left.
2076 **
2077 ** Notes on zCnName:
2078 ** The zCnName field stores the name of the column, the datatype of the
2079 ** column, and the collating sequence for the column, in that order, all in
2080 ** a single allocation.  Each string is 0x00 terminated.  The datatype
2081 ** is only included if the COLFLAG_HASTYPE bit of colFlags is set and the
2082 ** collating sequence name is only included if the COLFLAG_HASCOLL bit is
2083 ** set.
2084 */
2085 struct Column {
2086   char *zCnName;        /* Name of this column */
2087   unsigned notNull :4;  /* An OE_ code for handling a NOT NULL constraint */
2088   unsigned eCType :4;   /* One of the standard types */
2089   char affinity;        /* One of the SQLITE_AFF_... values */
2090   u8 szEst;             /* Est size of value in this column. sizeof(INT)==1 */
2091   u8 hName;             /* Column name hash for faster lookup */
2092   u16 iDflt;            /* 1-based index of DEFAULT.  0 means "none" */
2093   u16 colFlags;         /* Boolean properties.  See COLFLAG_ defines below */
2094 };
2095 
2096 /* Allowed values for Column.eCType.
2097 **
2098 ** Values must match entries in the global constant arrays
2099 ** sqlite3StdTypeLen[] and sqlite3StdType[].  Each value is one more
2100 ** than the offset into these arrays for the corresponding name.
2101 ** Adjust the SQLITE_N_STDTYPE value if adding or removing entries.
2102 */
2103 #define COLTYPE_CUSTOM      0   /* Type appended to zName */
2104 #define COLTYPE_ANY         1
2105 #define COLTYPE_BLOB        2
2106 #define COLTYPE_INT         3
2107 #define COLTYPE_INTEGER     4
2108 #define COLTYPE_REAL        5
2109 #define COLTYPE_TEXT        6
2110 #define SQLITE_N_STDTYPE    6  /* Number of standard types */
2111 
2112 /* Allowed values for Column.colFlags.
2113 **
2114 ** Constraints:
2115 **         TF_HasVirtual == COLFLAG_VIRTUAL
2116 **         TF_HasStored  == COLFLAG_STORED
2117 **         TF_HasHidden  == COLFLAG_HIDDEN
2118 */
2119 #define COLFLAG_PRIMKEY   0x0001   /* Column is part of the primary key */
2120 #define COLFLAG_HIDDEN    0x0002   /* A hidden column in a virtual table */
2121 #define COLFLAG_HASTYPE   0x0004   /* Type name follows column name */
2122 #define COLFLAG_UNIQUE    0x0008   /* Column def contains "UNIQUE" or "PK" */
2123 #define COLFLAG_SORTERREF 0x0010   /* Use sorter-refs with this column */
2124 #define COLFLAG_VIRTUAL   0x0020   /* GENERATED ALWAYS AS ... VIRTUAL */
2125 #define COLFLAG_STORED    0x0040   /* GENERATED ALWAYS AS ... STORED */
2126 #define COLFLAG_NOTAVAIL  0x0080   /* STORED column not yet calculated */
2127 #define COLFLAG_BUSY      0x0100   /* Blocks recursion on GENERATED columns */
2128 #define COLFLAG_HASCOLL   0x0200   /* Has collating sequence name in zCnName */
2129 #define COLFLAG_GENERATED 0x0060   /* Combo: _STORED, _VIRTUAL */
2130 #define COLFLAG_NOINSERT  0x0062   /* Combo: _HIDDEN, _STORED, _VIRTUAL */
2131 
2132 /*
2133 ** A "Collating Sequence" is defined by an instance of the following
2134 ** structure. Conceptually, a collating sequence consists of a name and
2135 ** a comparison routine that defines the order of that sequence.
2136 **
2137 ** If CollSeq.xCmp is NULL, it means that the
2138 ** collating sequence is undefined.  Indices built on an undefined
2139 ** collating sequence may not be read or written.
2140 */
2141 struct CollSeq {
2142   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
2143   u8 enc;               /* Text encoding handled by xCmp() */
2144   void *pUser;          /* First argument to xCmp() */
2145   int (*xCmp)(void*,int, const void*, int, const void*);
2146   void (*xDel)(void*);  /* Destructor for pUser */
2147 };
2148 
2149 /*
2150 ** A sort order can be either ASC or DESC.
2151 */
2152 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
2153 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
2154 #define SQLITE_SO_UNDEFINED -1 /* No sort order specified */
2155 
2156 /*
2157 ** Column affinity types.
2158 **
2159 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
2160 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
2161 ** the speed a little by numbering the values consecutively.
2162 **
2163 ** But rather than start with 0 or 1, we begin with 'A'.  That way,
2164 ** when multiple affinity types are concatenated into a string and
2165 ** used as the P4 operand, they will be more readable.
2166 **
2167 ** Note also that the numeric types are grouped together so that testing
2168 ** for a numeric type is a single comparison.  And the BLOB type is first.
2169 */
2170 #define SQLITE_AFF_NONE     0x40  /* '@' */
2171 #define SQLITE_AFF_BLOB     0x41  /* 'A' */
2172 #define SQLITE_AFF_TEXT     0x42  /* 'B' */
2173 #define SQLITE_AFF_NUMERIC  0x43  /* 'C' */
2174 #define SQLITE_AFF_INTEGER  0x44  /* 'D' */
2175 #define SQLITE_AFF_REAL     0x45  /* 'E' */
2176 
2177 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
2178 
2179 /*
2180 ** The SQLITE_AFF_MASK values masks off the significant bits of an
2181 ** affinity value.
2182 */
2183 #define SQLITE_AFF_MASK     0x47
2184 
2185 /*
2186 ** Additional bit values that can be ORed with an affinity without
2187 ** changing the affinity.
2188 **
2189 ** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
2190 ** It causes an assert() to fire if either operand to a comparison
2191 ** operator is NULL.  It is added to certain comparison operators to
2192 ** prove that the operands are always NOT NULL.
2193 */
2194 #define SQLITE_JUMPIFNULL   0x10  /* jumps if either operand is NULL */
2195 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
2196 #define SQLITE_NOTNULL      0x90  /* Assert that operands are never NULL */
2197 
2198 /*
2199 ** An object of this type is created for each virtual table present in
2200 ** the database schema.
2201 **
2202 ** If the database schema is shared, then there is one instance of this
2203 ** structure for each database connection (sqlite3*) that uses the shared
2204 ** schema. This is because each database connection requires its own unique
2205 ** instance of the sqlite3_vtab* handle used to access the virtual table
2206 ** implementation. sqlite3_vtab* handles can not be shared between
2207 ** database connections, even when the rest of the in-memory database
2208 ** schema is shared, as the implementation often stores the database
2209 ** connection handle passed to it via the xConnect() or xCreate() method
2210 ** during initialization internally. This database connection handle may
2211 ** then be used by the virtual table implementation to access real tables
2212 ** within the database. So that they appear as part of the callers
2213 ** transaction, these accesses need to be made via the same database
2214 ** connection as that used to execute SQL operations on the virtual table.
2215 **
2216 ** All VTable objects that correspond to a single table in a shared
2217 ** database schema are initially stored in a linked-list pointed to by
2218 ** the Table.pVTable member variable of the corresponding Table object.
2219 ** When an sqlite3_prepare() operation is required to access the virtual
2220 ** table, it searches the list for the VTable that corresponds to the
2221 ** database connection doing the preparing so as to use the correct
2222 ** sqlite3_vtab* handle in the compiled query.
2223 **
2224 ** When an in-memory Table object is deleted (for example when the
2225 ** schema is being reloaded for some reason), the VTable objects are not
2226 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
2227 ** immediately. Instead, they are moved from the Table.pVTable list to
2228 ** another linked list headed by the sqlite3.pDisconnect member of the
2229 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
2230 ** next time a statement is prepared using said sqlite3*. This is done
2231 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
2232 ** Refer to comments above function sqlite3VtabUnlockList() for an
2233 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
2234 ** list without holding the corresponding sqlite3.mutex mutex.
2235 **
2236 ** The memory for objects of this type is always allocated by
2237 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
2238 ** the first argument.
2239 */
2240 struct VTable {
2241   sqlite3 *db;              /* Database connection associated with this table */
2242   Module *pMod;             /* Pointer to module implementation */
2243   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
2244   int nRef;                 /* Number of pointers to this structure */
2245   u8 bConstraint;           /* True if constraints are supported */
2246   u8 eVtabRisk;             /* Riskiness of allowing hacker access */
2247   int iSavepoint;           /* Depth of the SAVEPOINT stack */
2248   VTable *pNext;            /* Next in linked list (see above) */
2249 };
2250 
2251 /* Allowed values for VTable.eVtabRisk
2252 */
2253 #define SQLITE_VTABRISK_Low          0
2254 #define SQLITE_VTABRISK_Normal       1
2255 #define SQLITE_VTABRISK_High         2
2256 
2257 /*
2258 ** The schema for each SQL table, virtual table, and view is represented
2259 ** in memory by an instance of the following structure.
2260 */
2261 struct Table {
2262   char *zName;         /* Name of the table or view */
2263   Column *aCol;        /* Information about each column */
2264   Index *pIndex;       /* List of SQL indexes on this table. */
2265   char *zColAff;       /* String defining the affinity of each column */
2266   ExprList *pCheck;    /* All CHECK constraints */
2267                        /*   ... also used as column name list in a VIEW */
2268   Pgno tnum;           /* Root BTree page for this table */
2269   u32 nTabRef;         /* Number of pointers to this Table */
2270   u32 tabFlags;        /* Mask of TF_* values */
2271   i16 iPKey;           /* If not negative, use aCol[iPKey] as the rowid */
2272   i16 nCol;            /* Number of columns in this table */
2273   i16 nNVCol;          /* Number of columns that are not VIRTUAL */
2274   LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
2275   LogEst szTabRow;     /* Estimated size of each table row in bytes */
2276 #ifdef SQLITE_ENABLE_COSTMULT
2277   LogEst costMult;     /* Cost multiplier for using this table */
2278 #endif
2279   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
2280   u8 eTabType;         /* 0: normal, 1: virtual, 2: view */
2281   union {
2282     struct {             /* Used by ordinary tables: */
2283       int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
2284       FKey *pFKey;         /* Linked list of all foreign keys in this table */
2285       ExprList *pDfltList; /* DEFAULT clauses on various columns.
2286                            ** Or the AS clause for generated columns. */
2287     } tab;
2288     struct {             /* Used by views: */
2289       Select *pSelect;     /* View definition */
2290     } view;
2291     struct {             /* Used by virtual tables only: */
2292       int nArg;            /* Number of arguments to the module */
2293       char **azArg;        /* 0: module 1: schema 2: vtab name 3...: args */
2294       VTable *p;           /* List of VTable objects. */
2295     } vtab;
2296   } u;
2297   Trigger *pTrigger;   /* List of triggers on this object */
2298   Schema *pSchema;     /* Schema that contains this table */
2299 };
2300 
2301 /*
2302 ** Allowed values for Table.tabFlags.
2303 **
2304 ** TF_OOOHidden applies to tables or view that have hidden columns that are
2305 ** followed by non-hidden columns.  Example:  "CREATE VIRTUAL TABLE x USING
2306 ** vtab1(a HIDDEN, b);".  Since "b" is a non-hidden column but "a" is hidden,
2307 ** the TF_OOOHidden attribute would apply in this case.  Such tables require
2308 ** special handling during INSERT processing. The "OOO" means "Out Of Order".
2309 **
2310 ** Constraints:
2311 **
2312 **         TF_HasVirtual == COLFLAG_VIRTUAL
2313 **         TF_HasStored  == COLFLAG_STORED
2314 **         TF_HasHidden  == COLFLAG_HIDDEN
2315 */
2316 #define TF_Readonly       0x00000001 /* Read-only system table */
2317 #define TF_HasHidden      0x00000002 /* Has one or more hidden columns */
2318 #define TF_HasPrimaryKey  0x00000004 /* Table has a primary key */
2319 #define TF_Autoincrement  0x00000008 /* Integer primary key is autoincrement */
2320 #define TF_HasStat1       0x00000010 /* nRowLogEst set from sqlite_stat1 */
2321 #define TF_HasVirtual     0x00000020 /* Has one or more VIRTUAL columns */
2322 #define TF_HasStored      0x00000040 /* Has one or more STORED columns */
2323 #define TF_HasGenerated   0x00000060 /* Combo: HasVirtual + HasStored */
2324 #define TF_WithoutRowid   0x00000080 /* No rowid.  PRIMARY KEY is the key */
2325 #define TF_StatsUsed      0x00000100 /* Query planner decisions affected by
2326                                      ** Index.aiRowLogEst[] values */
2327 #define TF_NoVisibleRowid 0x00000200 /* No user-visible "rowid" column */
2328 #define TF_OOOHidden      0x00000400 /* Out-of-Order hidden columns */
2329 #define TF_HasNotNull     0x00000800 /* Contains NOT NULL constraints */
2330 #define TF_Shadow         0x00001000 /* True for a shadow table */
2331 #define TF_HasStat4       0x00002000 /* STAT4 info available for this table */
2332 #define TF_Ephemeral      0x00004000 /* An ephemeral table */
2333 #define TF_Eponymous      0x00008000 /* An eponymous virtual table */
2334 #define TF_Strict         0x00010000 /* STRICT mode */
2335 
2336 /*
2337 ** Allowed values for Table.eTabType
2338 */
2339 #define TABTYP_NORM      0     /* Ordinary table */
2340 #define TABTYP_VTAB      1     /* Virtual table */
2341 #define TABTYP_VIEW      2     /* A view */
2342 
2343 #define IsView(X)           ((X)->eTabType==TABTYP_VIEW)
2344 #define IsOrdinaryTable(X)  ((X)->eTabType==TABTYP_NORM)
2345 
2346 /*
2347 ** Test to see whether or not a table is a virtual table.  This is
2348 ** done as a macro so that it will be optimized out when virtual
2349 ** table support is omitted from the build.
2350 */
2351 #ifndef SQLITE_OMIT_VIRTUALTABLE
2352 #  define IsVirtual(X)      ((X)->eTabType==TABTYP_VTAB)
2353 #  define ExprIsVtab(X)  \
2354     ((X)->op==TK_COLUMN && (X)->y.pTab!=0 && (X)->y.pTab->eTabType==TABTYP_VTAB)
2355 #else
2356 #  define IsVirtual(X)      0
2357 #  define ExprIsVtab(X)     0
2358 #endif
2359 
2360 /*
2361 ** Macros to determine if a column is hidden.  IsOrdinaryHiddenColumn()
2362 ** only works for non-virtual tables (ordinary tables and views) and is
2363 ** always false unless SQLITE_ENABLE_HIDDEN_COLUMNS is defined.  The
2364 ** IsHiddenColumn() macro is general purpose.
2365 */
2366 #if defined(SQLITE_ENABLE_HIDDEN_COLUMNS)
2367 #  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
2368 #  define IsOrdinaryHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
2369 #elif !defined(SQLITE_OMIT_VIRTUALTABLE)
2370 #  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
2371 #  define IsOrdinaryHiddenColumn(X) 0
2372 #else
2373 #  define IsHiddenColumn(X)         0
2374 #  define IsOrdinaryHiddenColumn(X) 0
2375 #endif
2376 
2377 
2378 /* Does the table have a rowid */
2379 #define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
2380 #define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)
2381 
2382 /*
2383 ** Each foreign key constraint is an instance of the following structure.
2384 **
2385 ** A foreign key is associated with two tables.  The "from" table is
2386 ** the table that contains the REFERENCES clause that creates the foreign
2387 ** key.  The "to" table is the table that is named in the REFERENCES clause.
2388 ** Consider this example:
2389 **
2390 **     CREATE TABLE ex1(
2391 **       a INTEGER PRIMARY KEY,
2392 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
2393 **     );
2394 **
2395 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
2396 ** Equivalent names:
2397 **
2398 **     from-table == child-table
2399 **       to-table == parent-table
2400 **
2401 ** Each REFERENCES clause generates an instance of the following structure
2402 ** which is attached to the from-table.  The to-table need not exist when
2403 ** the from-table is created.  The existence of the to-table is not checked.
2404 **
2405 ** The list of all parents for child Table X is held at X.pFKey.
2406 **
2407 ** A list of all children for a table named Z (which might not even exist)
2408 ** is held in Schema.fkeyHash with a hash key of Z.
2409 */
2410 struct FKey {
2411   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
2412   FKey *pNextFrom;  /* Next FKey with the same in pFrom. Next parent of pFrom */
2413   char *zTo;        /* Name of table that the key points to (aka: Parent) */
2414   FKey *pNextTo;    /* Next with the same zTo. Next child of zTo. */
2415   FKey *pPrevTo;    /* Previous with the same zTo */
2416   int nCol;         /* Number of columns in this key */
2417   /* EV: R-30323-21917 */
2418   u8 isDeferred;       /* True if constraint checking is deferred till COMMIT */
2419   u8 aAction[2];        /* ON DELETE and ON UPDATE actions, respectively */
2420   Trigger *apTrigger[2];/* Triggers for aAction[] actions */
2421   struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
2422     int iFrom;            /* Index of column in pFrom */
2423     char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
2424   } aCol[1];            /* One entry for each of nCol columns */
2425 };
2426 
2427 /*
2428 ** SQLite supports many different ways to resolve a constraint
2429 ** error.  ROLLBACK processing means that a constraint violation
2430 ** causes the operation in process to fail and for the current transaction
2431 ** to be rolled back.  ABORT processing means the operation in process
2432 ** fails and any prior changes from that one operation are backed out,
2433 ** but the transaction is not rolled back.  FAIL processing means that
2434 ** the operation in progress stops and returns an error code.  But prior
2435 ** changes due to the same operation are not backed out and no rollback
2436 ** occurs.  IGNORE means that the particular row that caused the constraint
2437 ** error is not inserted or updated.  Processing continues and no error
2438 ** is returned.  REPLACE means that preexisting database rows that caused
2439 ** a UNIQUE constraint violation are removed so that the new insert or
2440 ** update can proceed.  Processing continues and no error is reported.
2441 ** UPDATE applies to insert operations only and means that the insert
2442 ** is omitted and the DO UPDATE clause of an upsert is run instead.
2443 **
2444 ** RESTRICT, SETNULL, SETDFLT, and CASCADE actions apply only to foreign keys.
2445 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
2446 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
2447 ** key is set to NULL.  SETDFLT means that the foreign key is set
2448 ** to its default value.  CASCADE means that a DELETE or UPDATE of the
2449 ** referenced table row is propagated into the row that holds the
2450 ** foreign key.
2451 **
2452 ** The OE_Default value is a place holder that means to use whatever
2453 ** conflict resolution algorthm is required from context.
2454 **
2455 ** The following symbolic values are used to record which type
2456 ** of conflict resolution action to take.
2457 */
2458 #define OE_None     0   /* There is no constraint to check */
2459 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
2460 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
2461 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
2462 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
2463 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
2464 #define OE_Update   6   /* Process as a DO UPDATE in an upsert */
2465 #define OE_Restrict 7   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
2466 #define OE_SetNull  8   /* Set the foreign key value to NULL */
2467 #define OE_SetDflt  9   /* Set the foreign key value to its default */
2468 #define OE_Cascade  10  /* Cascade the changes */
2469 #define OE_Default  11  /* Do whatever the default action is */
2470 
2471 
2472 /*
2473 ** An instance of the following structure is passed as the first
2474 ** argument to sqlite3VdbeKeyCompare and is used to control the
2475 ** comparison of the two index keys.
2476 **
2477 ** Note that aSortOrder[] and aColl[] have nField+1 slots.  There
2478 ** are nField slots for the columns of an index then one extra slot
2479 ** for the rowid at the end.
2480 */
2481 struct KeyInfo {
2482   u32 nRef;           /* Number of references to this KeyInfo object */
2483   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
2484   u16 nKeyField;      /* Number of key columns in the index */
2485   u16 nAllField;      /* Total columns, including key plus others */
2486   sqlite3 *db;        /* The database connection */
2487   u8 *aSortFlags;     /* Sort order for each column. */
2488   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
2489 };
2490 
2491 /*
2492 ** Allowed bit values for entries in the KeyInfo.aSortFlags[] array.
2493 */
2494 #define KEYINFO_ORDER_DESC    0x01    /* DESC sort order */
2495 #define KEYINFO_ORDER_BIGNULL 0x02    /* NULL is larger than any other value */
2496 
2497 /*
2498 ** This object holds a record which has been parsed out into individual
2499 ** fields, for the purposes of doing a comparison.
2500 **
2501 ** A record is an object that contains one or more fields of data.
2502 ** Records are used to store the content of a table row and to store
2503 ** the key of an index.  A blob encoding of a record is created by
2504 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
2505 ** OP_Column opcode.
2506 **
2507 ** An instance of this object serves as a "key" for doing a search on
2508 ** an index b+tree. The goal of the search is to find the entry that
2509 ** is closed to the key described by this object.  This object might hold
2510 ** just a prefix of the key.  The number of fields is given by
2511 ** pKeyInfo->nField.
2512 **
2513 ** The r1 and r2 fields are the values to return if this key is less than
2514 ** or greater than a key in the btree, respectively.  These are normally
2515 ** -1 and +1 respectively, but might be inverted to +1 and -1 if the b-tree
2516 ** is in DESC order.
2517 **
2518 ** The key comparison functions actually return default_rc when they find
2519 ** an equals comparison.  default_rc can be -1, 0, or +1.  If there are
2520 ** multiple entries in the b-tree with the same key (when only looking
2521 ** at the first pKeyInfo->nFields,) then default_rc can be set to -1 to
2522 ** cause the search to find the last match, or +1 to cause the search to
2523 ** find the first match.
2524 **
2525 ** The key comparison functions will set eqSeen to true if they ever
2526 ** get and equal results when comparing this structure to a b-tree record.
2527 ** When default_rc!=0, the search might end up on the record immediately
2528 ** before the first match or immediately after the last match.  The
2529 ** eqSeen field will indicate whether or not an exact match exists in the
2530 ** b-tree.
2531 */
2532 struct UnpackedRecord {
2533   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
2534   Mem *aMem;          /* Values */
2535   union {
2536     char *z;            /* Cache of aMem[0].z for vdbeRecordCompareString() */
2537     i64 i;              /* Cache of aMem[0].u.i for vdbeRecordCompareInt() */
2538   } u;
2539   int n;              /* Cache of aMem[0].n used by vdbeRecordCompareString() */
2540   u16 nField;         /* Number of entries in apMem[] */
2541   i8 default_rc;      /* Comparison result if keys are equal */
2542   u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
2543   i8 r1;              /* Value to return if (lhs < rhs) */
2544   i8 r2;              /* Value to return if (lhs > rhs) */
2545   u8 eqSeen;          /* True if an equality comparison has been seen */
2546 };
2547 
2548 
2549 /*
2550 ** Each SQL index is represented in memory by an
2551 ** instance of the following structure.
2552 **
2553 ** The columns of the table that are to be indexed are described
2554 ** by the aiColumn[] field of this structure.  For example, suppose
2555 ** we have the following table and index:
2556 **
2557 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
2558 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
2559 **
2560 ** In the Table structure describing Ex1, nCol==3 because there are
2561 ** three columns in the table.  In the Index structure describing
2562 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
2563 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
2564 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
2565 ** The second column to be indexed (c1) has an index of 0 in
2566 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
2567 **
2568 ** The Index.onError field determines whether or not the indexed columns
2569 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
2570 ** it means this is not a unique index.  Otherwise it is a unique index
2571 ** and the value of Index.onError indicate the which conflict resolution
2572 ** algorithm to employ whenever an attempt is made to insert a non-unique
2573 ** element.
2574 **
2575 ** While parsing a CREATE TABLE or CREATE INDEX statement in order to
2576 ** generate VDBE code (as opposed to parsing one read from an sqlite_schema
2577 ** table as part of parsing an existing database schema), transient instances
2578 ** of this structure may be created. In this case the Index.tnum variable is
2579 ** used to store the address of a VDBE instruction, not a database page
2580 ** number (it cannot - the database page is not allocated until the VDBE
2581 ** program is executed). See convertToWithoutRowidTable() for details.
2582 */
2583 struct Index {
2584   char *zName;             /* Name of this index */
2585   i16 *aiColumn;           /* Which columns are used by this index.  1st is 0 */
2586   LogEst *aiRowLogEst;     /* From ANALYZE: Est. rows selected by each column */
2587   Table *pTable;           /* The SQL table being indexed */
2588   char *zColAff;           /* String defining the affinity of each column */
2589   Index *pNext;            /* The next index associated with the same table */
2590   Schema *pSchema;         /* Schema containing this index */
2591   u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
2592   const char **azColl;     /* Array of collation sequence names for index */
2593   Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
2594   ExprList *aColExpr;      /* Column expressions */
2595   Pgno tnum;               /* DB Page containing root of this index */
2596   LogEst szIdxRow;         /* Estimated average row size in bytes */
2597   u16 nKeyCol;             /* Number of columns forming the key */
2598   u16 nColumn;             /* Number of columns stored in the index */
2599   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
2600   unsigned idxType:2;      /* 0:Normal 1:UNIQUE, 2:PRIMARY KEY, 3:IPK */
2601   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
2602   unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
2603   unsigned isResized:1;    /* True if resizeIndexObject() has been called */
2604   unsigned isCovering:1;   /* True if this is a covering index */
2605   unsigned noSkipScan:1;   /* Do not try to use skip-scan if true */
2606   unsigned hasStat1:1;     /* aiRowLogEst values come from sqlite_stat1 */
2607   unsigned bNoQuery:1;     /* Do not use this index to optimize queries */
2608   unsigned bAscKeyBug:1;   /* True if the bba7b69f9849b5bf bug applies */
2609   unsigned bHasVCol:1;     /* Index references one or more VIRTUAL columns */
2610 #ifdef SQLITE_ENABLE_STAT4
2611   int nSample;             /* Number of elements in aSample[] */
2612   int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
2613   tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
2614   IndexSample *aSample;    /* Samples of the left-most key */
2615   tRowcnt *aiRowEst;       /* Non-logarithmic stat1 data for this index */
2616   tRowcnt nRowEst0;        /* Non-logarithmic number of rows in the index */
2617 #endif
2618   Bitmask colNotIdxed;     /* 0 for unindexed columns in pTab */
2619 };
2620 
2621 /*
2622 ** Allowed values for Index.idxType
2623 */
2624 #define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
2625 #define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */
2626 #define SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */
2627 #define SQLITE_IDXTYPE_IPK         3   /* INTEGER PRIMARY KEY index */
2628 
2629 /* Return true if index X is a PRIMARY KEY index */
2630 #define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
2631 
2632 /* Return true if index X is a UNIQUE index */
2633 #define IsUniqueIndex(X)      ((X)->onError!=OE_None)
2634 
2635 /* The Index.aiColumn[] values are normally positive integer.  But
2636 ** there are some negative values that have special meaning:
2637 */
2638 #define XN_ROWID     (-1)     /* Indexed column is the rowid */
2639 #define XN_EXPR      (-2)     /* Indexed column is an expression */
2640 
2641 /*
2642 ** Each sample stored in the sqlite_stat4 table is represented in memory
2643 ** using a structure of this type.  See documentation at the top of the
2644 ** analyze.c source file for additional information.
2645 */
2646 struct IndexSample {
2647   void *p;          /* Pointer to sampled record */
2648   int n;            /* Size of record in bytes */
2649   tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
2650   tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
2651   tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
2652 };
2653 
2654 /*
2655 ** Possible values to use within the flags argument to sqlite3GetToken().
2656 */
2657 #define SQLITE_TOKEN_QUOTED    0x1 /* Token is a quoted identifier. */
2658 #define SQLITE_TOKEN_KEYWORD   0x2 /* Token is a keyword. */
2659 
2660 /*
2661 ** Each token coming out of the lexer is an instance of
2662 ** this structure.  Tokens are also used as part of an expression.
2663 **
2664 ** The memory that "z" points to is owned by other objects.  Take care
2665 ** that the owner of the "z" string does not deallocate the string before
2666 ** the Token goes out of scope!  Very often, the "z" points to some place
2667 ** in the middle of the Parse.zSql text.  But it might also point to a
2668 ** static string.
2669 */
2670 struct Token {
2671   const char *z;     /* Text of the token.  Not NULL-terminated! */
2672   unsigned int n;    /* Number of characters in this token */
2673 };
2674 
2675 /*
2676 ** An instance of this structure contains information needed to generate
2677 ** code for a SELECT that contains aggregate functions.
2678 **
2679 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
2680 ** pointer to this structure.  The Expr.iAgg field is the index in
2681 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
2682 ** code for that node.
2683 **
2684 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
2685 ** original Select structure that describes the SELECT statement.  These
2686 ** fields do not need to be freed when deallocating the AggInfo structure.
2687 */
2688 struct AggInfo {
2689   u8 directMode;          /* Direct rendering mode means take data directly
2690                           ** from source tables rather than from accumulators */
2691   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
2692                           ** than the source table */
2693   int sortingIdx;         /* Cursor number of the sorting index */
2694   int sortingIdxPTab;     /* Cursor number of pseudo-table */
2695   int nSortingColumn;     /* Number of columns in the sorting index */
2696   int mnReg, mxReg;       /* Range of registers allocated for aCol and aFunc */
2697   ExprList *pGroupBy;     /* The group by clause */
2698   struct AggInfo_col {    /* For each column used in source tables */
2699     Table *pTab;             /* Source table */
2700     Expr *pCExpr;            /* The original expression */
2701     int iTable;              /* Cursor number of the source table */
2702     int iMem;                /* Memory location that acts as accumulator */
2703     i16 iColumn;             /* Column number within the source table */
2704     i16 iSorterColumn;       /* Column number in the sorting index */
2705   } *aCol;
2706   int nColumn;            /* Number of used entries in aCol[] */
2707   int nAccumulator;       /* Number of columns that show through to the output.
2708                           ** Additional columns are used only as parameters to
2709                           ** aggregate functions */
2710   struct AggInfo_func {   /* For each aggregate function */
2711     Expr *pFExpr;            /* Expression encoding the function */
2712     FuncDef *pFunc;          /* The aggregate function implementation */
2713     int iMem;                /* Memory location that acts as accumulator */
2714     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
2715     int iDistAddr;           /* Address of OP_OpenEphemeral */
2716   } *aFunc;
2717   int nFunc;              /* Number of entries in aFunc[] */
2718   u32 selId;              /* Select to which this AggInfo belongs */
2719 };
2720 
2721 /*
2722 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
2723 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
2724 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
2725 ** it uses less memory in the Expr object, which is a big memory user
2726 ** in systems with lots of prepared statements.  And few applications
2727 ** need more than about 10 or 20 variables.  But some extreme users want
2728 ** to have prepared statements with over 32766 variables, and for them
2729 ** the option is available (at compile-time).
2730 */
2731 #if SQLITE_MAX_VARIABLE_NUMBER<32767
2732 typedef i16 ynVar;
2733 #else
2734 typedef int ynVar;
2735 #endif
2736 
2737 /*
2738 ** Each node of an expression in the parse tree is an instance
2739 ** of this structure.
2740 **
2741 ** Expr.op is the opcode. The integer parser token codes are reused
2742 ** as opcodes here. For example, the parser defines TK_GE to be an integer
2743 ** code representing the ">=" operator. This same integer code is reused
2744 ** to represent the greater-than-or-equal-to operator in the expression
2745 ** tree.
2746 **
2747 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
2748 ** or TK_STRING), then Expr.u.zToken contains the text of the SQL literal. If
2749 ** the expression is a variable (TK_VARIABLE), then Expr.u.zToken contains the
2750 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
2751 ** then Expr.u.zToken contains the name of the function.
2752 **
2753 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
2754 ** binary operator. Either or both may be NULL.
2755 **
2756 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
2757 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
2758 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
2759 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
2760 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
2761 ** valid.
2762 **
2763 ** An expression of the form ID or ID.ID refers to a column in a table.
2764 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
2765 ** the integer cursor number of a VDBE cursor pointing to that table and
2766 ** Expr.iColumn is the column number for the specific column.  If the
2767 ** expression is used as a result in an aggregate SELECT, then the
2768 ** value is also stored in the Expr.iAgg column in the aggregate so that
2769 ** it can be accessed after all aggregates are computed.
2770 **
2771 ** If the expression is an unbound variable marker (a question mark
2772 ** character '?' in the original SQL) then the Expr.iTable holds the index
2773 ** number for that variable.
2774 **
2775 ** If the expression is a subquery then Expr.iColumn holds an integer
2776 ** register number containing the result of the subquery.  If the
2777 ** subquery gives a constant result, then iTable is -1.  If the subquery
2778 ** gives a different answer at different times during statement processing
2779 ** then iTable is the address of a subroutine that computes the subquery.
2780 **
2781 ** If the Expr is of type OP_Column, and the table it is selecting from
2782 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
2783 ** corresponding table definition.
2784 **
2785 ** ALLOCATION NOTES:
2786 **
2787 ** Expr objects can use a lot of memory space in database schema.  To
2788 ** help reduce memory requirements, sometimes an Expr object will be
2789 ** truncated.  And to reduce the number of memory allocations, sometimes
2790 ** two or more Expr objects will be stored in a single memory allocation,
2791 ** together with Expr.u.zToken strings.
2792 **
2793 ** If the EP_Reduced and EP_TokenOnly flags are set when
2794 ** an Expr object is truncated.  When EP_Reduced is set, then all
2795 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
2796 ** are contained within the same memory allocation.  Note, however, that
2797 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
2798 ** allocated, regardless of whether or not EP_Reduced is set.
2799 */
2800 struct Expr {
2801   u8 op;                 /* Operation performed by this node */
2802   char affExpr;          /* affinity, or RAISE type */
2803   u8 op2;                /* TK_REGISTER/TK_TRUTH: original value of Expr.op
2804                          ** TK_COLUMN: the value of p5 for OP_Column
2805                          ** TK_AGG_FUNCTION: nesting depth
2806                          ** TK_FUNCTION: NC_SelfRef flag if needs OP_PureFunc */
2807 #ifdef SQLITE_DEBUG
2808   u8 vvaFlags;           /* Verification flags. */
2809 #endif
2810   u32 flags;             /* Various flags.  EP_* See below */
2811   union {
2812     char *zToken;          /* Token value. Zero terminated and dequoted */
2813     int iValue;            /* Non-negative integer value if EP_IntValue */
2814   } u;
2815 
2816   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
2817   ** space is allocated for the fields below this point. An attempt to
2818   ** access them will result in a segfault or malfunction.
2819   *********************************************************************/
2820 
2821   Expr *pLeft;           /* Left subnode */
2822   Expr *pRight;          /* Right subnode */
2823   union {
2824     ExprList *pList;     /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
2825     Select *pSelect;     /* EP_xIsSelect and op = IN, EXISTS, SELECT */
2826   } x;
2827 
2828   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
2829   ** space is allocated for the fields below this point. An attempt to
2830   ** access them will result in a segfault or malfunction.
2831   *********************************************************************/
2832 
2833 #if SQLITE_MAX_EXPR_DEPTH>0
2834   int nHeight;           /* Height of the tree headed by this node */
2835 #endif
2836   int iTable;            /* TK_COLUMN: cursor number of table holding column
2837                          ** TK_REGISTER: register number
2838                          ** TK_TRIGGER: 1 -> new, 0 -> old
2839                          ** EP_Unlikely:  134217728 times likelihood
2840                          ** TK_IN: ephemerial table holding RHS
2841                          ** TK_SELECT_COLUMN: Number of columns on the LHS
2842                          ** TK_SELECT: 1st register of result vector */
2843   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
2844                          ** TK_VARIABLE: variable number (always >= 1).
2845                          ** TK_SELECT_COLUMN: column of the result vector */
2846   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
2847   union {
2848     int iJoin;             /* If EP_FromJoin, the right table of the join */
2849     int iOfst;             /* else: start of token from start of statement */
2850   } w;
2851   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
2852   union {
2853     Table *pTab;           /* TK_COLUMN: Table containing column. Can be NULL
2854                            ** for a column of an index on an expression */
2855     Window *pWin;          /* EP_WinFunc: Window/Filter defn for a function */
2856     struct {               /* TK_IN, TK_SELECT, and TK_EXISTS */
2857       int iAddr;             /* Subroutine entry address */
2858       int regReturn;         /* Register used to hold return address */
2859     } sub;
2860   } y;
2861 };
2862 
2863 /* The following are the meanings of bits in the Expr.flags field.
2864 ** Value restrictions:
2865 **
2866 **          EP_Agg == NC_HasAgg == SF_HasAgg
2867 **          EP_Win == NC_HasWin
2868 */
2869 #define EP_FromJoin   0x000001 /* Originates in ON/USING clause of outer join */
2870 #define EP_Distinct   0x000002 /* Aggregate function with DISTINCT keyword */
2871 #define EP_HasFunc    0x000004 /* Contains one or more functions of any kind */
2872 #define EP_FixedCol   0x000008 /* TK_Column with a known fixed value */
2873 #define EP_Agg        0x000010 /* Contains one or more aggregate functions */
2874 #define EP_VarSelect  0x000020 /* pSelect is correlated, not constant */
2875 #define EP_DblQuoted  0x000040 /* token.z was originally in "..." */
2876 #define EP_InfixFunc  0x000080 /* True for an infix function: LIKE, GLOB, etc */
2877 #define EP_Collate    0x000100 /* Tree contains a TK_COLLATE operator */
2878 #define EP_Commuted   0x000200 /* Comparison operator has been commuted */
2879 #define EP_IntValue   0x000400 /* Integer value contained in u.iValue */
2880 #define EP_xIsSelect  0x000800 /* x.pSelect is valid (otherwise x.pList is) */
2881 #define EP_Skip       0x001000 /* Operator does not contribute to affinity */
2882 #define EP_Reduced    0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
2883 #define EP_TokenOnly  0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
2884 #define EP_Win        0x008000 /* Contains window functions */
2885 #define EP_MemToken   0x010000 /* Need to sqlite3DbFree() Expr.zToken */
2886 #define EP_IfNullRow  0x020000 /* The TK_IF_NULL_ROW opcode */
2887 #define EP_Unlikely   0x040000 /* unlikely() or likelihood() function */
2888 #define EP_ConstFunc  0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
2889 #define EP_CanBeNull  0x100000 /* Can be null despite NOT NULL constraint */
2890 #define EP_Subquery   0x200000 /* Tree contains a TK_SELECT operator */
2891 #define EP_InnerJoin  0x400000 /* Originates in ON/USING of an inner join */
2892 #define EP_Leaf       0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
2893 #define EP_WinFunc   0x1000000 /* TK_FUNCTION with Expr.y.pWin set */
2894 #define EP_Subrtn    0x2000000 /* Uses Expr.y.sub. TK_IN, _SELECT, or _EXISTS */
2895 #define EP_Quoted    0x4000000 /* TK_ID was originally quoted */
2896 #define EP_Static    0x8000000 /* Held in memory not obtained from malloc() */
2897 #define EP_IsTrue   0x10000000 /* Always has boolean value of TRUE */
2898 #define EP_IsFalse  0x20000000 /* Always has boolean value of FALSE */
2899 #define EP_FromDDL  0x40000000 /* Originates from sqlite_schema */
2900                /*   0x80000000 // Available */
2901 
2902 /* The EP_Propagate mask is a set of properties that automatically propagate
2903 ** upwards into parent nodes.
2904 */
2905 #define EP_Propagate (EP_Collate|EP_Subquery|EP_HasFunc)
2906 
2907 /* Macros can be used to test, set, or clear bits in the
2908 ** Expr.flags field.
2909 */
2910 #define ExprHasProperty(E,P)     (((E)->flags&(P))!=0)
2911 #define ExprHasAllProperty(E,P)  (((E)->flags&(P))==(P))
2912 #define ExprSetProperty(E,P)     (E)->flags|=(P)
2913 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
2914 #define ExprAlwaysTrue(E)   (((E)->flags&(EP_FromJoin|EP_IsTrue))==EP_IsTrue)
2915 #define ExprAlwaysFalse(E)  (((E)->flags&(EP_FromJoin|EP_IsFalse))==EP_IsFalse)
2916 
2917 /* Macros used to ensure that the correct members of unions are accessed
2918 ** in Expr.
2919 */
2920 #define ExprUseUToken(E)    (((E)->flags&EP_IntValue)==0)
2921 #define ExprUseUValue(E)    (((E)->flags&EP_IntValue)!=0)
2922 #define ExprUseXList(E)     (((E)->flags&EP_xIsSelect)==0)
2923 #define ExprUseXSelect(E)   (((E)->flags&EP_xIsSelect)!=0)
2924 #define ExprUseYTab(E)      (((E)->flags&(EP_WinFunc|EP_Subrtn))==0)
2925 #define ExprUseYWin(E)      (((E)->flags&EP_WinFunc)!=0)
2926 #define ExprUseYSub(E)      (((E)->flags&EP_Subrtn)!=0)
2927 
2928 /* Flags for use with Expr.vvaFlags
2929 */
2930 #define EP_NoReduce   0x01  /* Cannot EXPRDUP_REDUCE this Expr */
2931 #define EP_Immutable  0x02  /* Do not change this Expr node */
2932 
2933 /* The ExprSetVVAProperty() macro is used for Verification, Validation,
2934 ** and Accreditation only.  It works like ExprSetProperty() during VVA
2935 ** processes but is a no-op for delivery.
2936 */
2937 #ifdef SQLITE_DEBUG
2938 # define ExprSetVVAProperty(E,P)   (E)->vvaFlags|=(P)
2939 # define ExprHasVVAProperty(E,P)   (((E)->vvaFlags&(P))!=0)
2940 # define ExprClearVVAProperties(E) (E)->vvaFlags = 0
2941 #else
2942 # define ExprSetVVAProperty(E,P)
2943 # define ExprHasVVAProperty(E,P)   0
2944 # define ExprClearVVAProperties(E)
2945 #endif
2946 
2947 /*
2948 ** Macros to determine the number of bytes required by a normal Expr
2949 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
2950 ** and an Expr struct with the EP_TokenOnly flag set.
2951 */
2952 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
2953 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
2954 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
2955 
2956 /*
2957 ** Flags passed to the sqlite3ExprDup() function. See the header comment
2958 ** above sqlite3ExprDup() for details.
2959 */
2960 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
2961 
2962 /*
2963 ** True if the expression passed as an argument was a function with
2964 ** an OVER() clause (a window function).
2965 */
2966 #ifdef SQLITE_OMIT_WINDOWFUNC
2967 # define IsWindowFunc(p) 0
2968 #else
2969 # define IsWindowFunc(p) ( \
2970     ExprHasProperty((p), EP_WinFunc) && p->y.pWin->eFrmType!=TK_FILTER \
2971  )
2972 #endif
2973 
2974 /*
2975 ** A list of expressions.  Each expression may optionally have a
2976 ** name.  An expr/name combination can be used in several ways, such
2977 ** as the list of "expr AS ID" fields following a "SELECT" or in the
2978 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
2979 ** also be used as the argument to a function, in which case the a.zName
2980 ** field is not used.
2981 **
2982 ** In order to try to keep memory usage down, the Expr.a.zEName field
2983 ** is used for multiple purposes:
2984 **
2985 **     eEName          Usage
2986 **    ----------       -------------------------
2987 **    ENAME_NAME       (1) the AS of result set column
2988 **                     (2) COLUMN= of an UPDATE
2989 **
2990 **    ENAME_TAB        DB.TABLE.NAME used to resolve names
2991 **                     of subqueries
2992 **
2993 **    ENAME_SPAN       Text of the original result set
2994 **                     expression.
2995 */
2996 struct ExprList {
2997   int nExpr;             /* Number of expressions on the list */
2998   int nAlloc;            /* Number of a[] slots allocated */
2999   struct ExprList_item { /* For each expression in the list */
3000     Expr *pExpr;            /* The parse tree for this expression */
3001     char *zEName;           /* Token associated with this expression */
3002     u8 sortFlags;           /* Mask of KEYINFO_ORDER_* flags */
3003     unsigned eEName :2;     /* Meaning of zEName */
3004     unsigned done :1;       /* A flag to indicate when processing is finished */
3005     unsigned reusable :1;   /* Constant expression is reusable */
3006     unsigned bSorterRef :1; /* Defer evaluation until after sorting */
3007     unsigned bNulls: 1;     /* True if explicit "NULLS FIRST/LAST" */
3008     unsigned bUsed: 1;      /* This column used in a SF_NestedFrom subquery */
3009     union {
3010       struct {             /* Used by any ExprList other than Parse.pConsExpr */
3011         u16 iOrderByCol;      /* For ORDER BY, column number in result set */
3012         u16 iAlias;           /* Index into Parse.aAlias[] for zName */
3013       } x;
3014       int iConstExprReg;   /* Register in which Expr value is cached. Used only
3015                            ** by Parse.pConstExpr */
3016     } u;
3017   } a[1];                  /* One slot for each expression in the list */
3018 };
3019 
3020 /*
3021 ** Allowed values for Expr.a.eEName
3022 */
3023 #define ENAME_NAME  0       /* The AS clause of a result set */
3024 #define ENAME_SPAN  1       /* Complete text of the result set expression */
3025 #define ENAME_TAB   2       /* "DB.TABLE.NAME" for the result set */
3026 
3027 /*
3028 ** An instance of this structure can hold a simple list of identifiers,
3029 ** such as the list "a,b,c" in the following statements:
3030 **
3031 **      INSERT INTO t(a,b,c) VALUES ...;
3032 **      CREATE INDEX idx ON t(a,b,c);
3033 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
3034 **
3035 ** The IdList.a.idx field is used when the IdList represents the list of
3036 ** column names after a table name in an INSERT statement.  In the statement
3037 **
3038 **     INSERT INTO t(a,b,c) ...
3039 **
3040 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
3041 */
3042 struct IdList {
3043   int nId;         /* Number of identifiers on the list */
3044   u8 eU4;          /* Which element of a.u4 is valid */
3045   struct IdList_item {
3046     char *zName;      /* Name of the identifier */
3047     union {
3048       int idx;          /* Index in some Table.aCol[] of a column named zName */
3049       Expr *pExpr;      /* Expr to implement a USING variable -- NOT USED */
3050     } u4;
3051   } a[1];
3052 };
3053 
3054 /*
3055 ** Allowed values for IdList.eType, which determines which value of the a.u4
3056 ** is valid.
3057 */
3058 #define EU4_NONE   0   /* Does not use IdList.a.u4 */
3059 #define EU4_IDX    1   /* Uses IdList.a.u4.idx */
3060 #define EU4_EXPR   2   /* Uses IdList.a.u4.pExpr -- NOT CURRENTLY USED */
3061 
3062 /*
3063 ** The SrcItem object represents a single term in the FROM clause of a query.
3064 ** The SrcList object is mostly an array of SrcItems.
3065 **
3066 ** Union member validity:
3067 **
3068 **    u1.zIndexedBy          fg.isIndexedBy && !fg.isTabFunc
3069 **    u1.pFuncArg            fg.isTabFunc   && !fg.isIndexedBy
3070 **    u2.pIBIndex            fg.isIndexedBy && !fg.isCte
3071 **    u2.pCteUse             fg.isCte       && !fg.isIndexedBy
3072 */
3073 struct SrcItem {
3074   Schema *pSchema;  /* Schema to which this item is fixed */
3075   char *zDatabase;  /* Name of database holding this table */
3076   char *zName;      /* Name of the table */
3077   char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
3078   Table *pTab;      /* An SQL table corresponding to zName */
3079   Select *pSelect;  /* A SELECT statement used in place of a table name */
3080   int addrFillSub;  /* Address of subroutine to manifest a subquery */
3081   int regReturn;    /* Register holding return address of addrFillSub */
3082   int regResult;    /* Registers holding results of a co-routine */
3083   struct {
3084     u8 jointype;      /* Type of join between this table and the previous */
3085     unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
3086     unsigned isIndexedBy :1;   /* True if there is an INDEXED BY clause */
3087     unsigned isTabFunc :1;     /* True if table-valued-function syntax */
3088     unsigned isCorrelated :1;  /* True if sub-query is correlated */
3089     unsigned viaCoroutine :1;  /* Implemented as a co-routine */
3090     unsigned isRecursive :1;   /* True for recursive reference in WITH */
3091     unsigned fromDDL :1;       /* Comes from sqlite_schema */
3092     unsigned isCte :1;         /* This is a CTE */
3093     unsigned notCte :1;        /* This item may not match a CTE */
3094     unsigned isUsing :1;       /* u3.pUsing is valid */
3095     unsigned isSynthUsing :1;  /* u3.pUsing is synthensized from NATURAL */
3096     unsigned isNestedFrom :1;  /* pSelect is a SF_NestedFrom subquery */
3097   } fg;
3098   int iCursor;      /* The VDBE cursor number used to access this table */
3099   union {
3100     Expr *pOn;        /* fg.isUsing==0 =>  The ON clause of a join */
3101     IdList *pUsing;   /* fg.isUsing==1 =>  The USING clause of a join */
3102   } u3;
3103   Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
3104   union {
3105     char *zIndexedBy;    /* Identifier from "INDEXED BY <zIndex>" clause */
3106     ExprList *pFuncArg;  /* Arguments to table-valued-function */
3107   } u1;
3108   union {
3109     Index *pIBIndex;  /* Index structure corresponding to u1.zIndexedBy */
3110     CteUse *pCteUse;  /* CTE Usage info info fg.isCte is true */
3111   } u2;
3112 };
3113 
3114 /*
3115 ** The OnOrUsing object represents either an ON clause or a USING clause.
3116 ** It can never be both at the same time, but it can be neither.
3117 */
3118 struct OnOrUsing {
3119   Expr *pOn;         /* The ON clause of a join */
3120   IdList *pUsing;    /* The USING clause of a join */
3121 };
3122 
3123 /*
3124 ** The following structure describes the FROM clause of a SELECT statement.
3125 ** Each table or subquery in the FROM clause is a separate element of
3126 ** the SrcList.a[] array.
3127 **
3128 ** With the addition of multiple database support, the following structure
3129 ** can also be used to describe a particular table such as the table that
3130 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
3131 ** such a table must be a simple name: ID.  But in SQLite, the table can
3132 ** now be identified by a database name, a dot, then the table name: ID.ID.
3133 **
3134 ** The jointype starts out showing the join type between the current table
3135 ** and the next table on the list.  The parser builds the list this way.
3136 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
3137 ** jointype expresses the join between the table and the previous table.
3138 **
3139 ** In the colUsed field, the high-order bit (bit 63) is set if the table
3140 ** contains more than 63 columns and the 64-th or later column is used.
3141 */
3142 struct SrcList {
3143   int nSrc;        /* Number of tables or subqueries in the FROM clause */
3144   u32 nAlloc;      /* Number of entries allocated in a[] below */
3145   SrcItem a[1];    /* One entry for each identifier on the list */
3146 };
3147 
3148 /*
3149 ** Permitted values of the SrcList.a.jointype field
3150 */
3151 #define JT_INNER     0x01    /* Any kind of inner or cross join */
3152 #define JT_CROSS     0x02    /* Explicit use of the CROSS keyword */
3153 #define JT_NATURAL   0x04    /* True for a "natural" join */
3154 #define JT_LEFT      0x08    /* Left outer join */
3155 #define JT_RIGHT     0x10    /* Right outer join */
3156 #define JT_OUTER     0x20    /* The "OUTER" keyword is present */
3157 #define JT_LTORJ     0x40    /* One of the LEFT operands of a RIGHT JOIN
3158                              ** Mnemonic: Left Table Of Right Join */
3159 #define JT_ERROR     0x80    /* unknown or unsupported join type */
3160 
3161 /*
3162 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
3163 ** and the WhereInfo.wctrlFlags member.
3164 **
3165 ** Value constraints (enforced via assert()):
3166 **     WHERE_USE_LIMIT  == SF_FixedLimit
3167 */
3168 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
3169 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
3170 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
3171 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
3172 #define WHERE_ONEPASS_MULTIROW 0x0008 /* ONEPASS is ok with multiple rows */
3173 #define WHERE_DUPLICATES_OK    0x0010 /* Ok to return a row more than once */
3174 #define WHERE_OR_SUBCLAUSE     0x0020 /* Processing a sub-WHERE as part of
3175                                       ** the OR optimization  */
3176 #define WHERE_GROUPBY          0x0040 /* pOrderBy is really a GROUP BY */
3177 #define WHERE_DISTINCTBY       0x0080 /* pOrderby is really a DISTINCT clause */
3178 #define WHERE_WANT_DISTINCT    0x0100 /* All output needs to be distinct */
3179 #define WHERE_SORTBYGROUP      0x0200 /* Support sqlite3WhereIsSorted() */
3180 #define WHERE_AGG_DISTINCT     0x0400 /* Query is "SELECT agg(DISTINCT ...)" */
3181 #define WHERE_ORDERBY_LIMIT    0x0800 /* ORDERBY+LIMIT on the inner loop */
3182 #define WHERE_RIGHT_JOIN       0x1000 /* Processing a RIGHT JOIN */
3183                         /*     0x2000    not currently used */
3184 #define WHERE_USE_LIMIT        0x4000 /* Use the LIMIT in cost estimates */
3185                         /*     0x8000    not currently used */
3186 
3187 /* Allowed return values from sqlite3WhereIsDistinct()
3188 */
3189 #define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
3190 #define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
3191 #define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
3192 #define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
3193 
3194 /*
3195 ** A NameContext defines a context in which to resolve table and column
3196 ** names.  The context consists of a list of tables (the pSrcList) field and
3197 ** a list of named expression (pEList).  The named expression list may
3198 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
3199 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
3200 ** pEList corresponds to the result set of a SELECT and is NULL for
3201 ** other statements.
3202 **
3203 ** NameContexts can be nested.  When resolving names, the inner-most
3204 ** context is searched first.  If no match is found, the next outer
3205 ** context is checked.  If there is still no match, the next context
3206 ** is checked.  This process continues until either a match is found
3207 ** or all contexts are check.  When a match is found, the nRef member of
3208 ** the context containing the match is incremented.
3209 **
3210 ** Each subquery gets a new NameContext.  The pNext field points to the
3211 ** NameContext in the parent query.  Thus the process of scanning the
3212 ** NameContext list corresponds to searching through successively outer
3213 ** subqueries looking for a match.
3214 */
3215 struct NameContext {
3216   Parse *pParse;       /* The parser */
3217   SrcList *pSrcList;   /* One or more tables used to resolve names */
3218   union {
3219     ExprList *pEList;    /* Optional list of result-set columns */
3220     AggInfo *pAggInfo;   /* Information about aggregates at this level */
3221     Upsert *pUpsert;     /* ON CONFLICT clause information from an upsert */
3222     int iBaseReg;        /* For TK_REGISTER when parsing RETURNING */
3223   } uNC;
3224   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
3225   int nRef;            /* Number of names resolved by this context */
3226   int nNcErr;          /* Number of errors encountered while resolving names */
3227   int ncFlags;         /* Zero or more NC_* flags defined below */
3228   Select *pWinSelect;  /* SELECT statement for any window functions */
3229 };
3230 
3231 /*
3232 ** Allowed values for the NameContext, ncFlags field.
3233 **
3234 ** Value constraints (all checked via assert()):
3235 **    NC_HasAgg    == SF_HasAgg       == EP_Agg
3236 **    NC_MinMaxAgg == SF_MinMaxAgg    == SQLITE_FUNC_MINMAX
3237 **    NC_OrderAgg  == SF_OrderByReqd  == SQLITE_FUNC_ANYORDER
3238 **    NC_HasWin    == EP_Win
3239 **
3240 */
3241 #define NC_AllowAgg  0x000001 /* Aggregate functions are allowed here */
3242 #define NC_PartIdx   0x000002 /* True if resolving a partial index WHERE */
3243 #define NC_IsCheck   0x000004 /* True if resolving a CHECK constraint */
3244 #define NC_GenCol    0x000008 /* True for a GENERATED ALWAYS AS clause */
3245 #define NC_HasAgg    0x000010 /* One or more aggregate functions seen */
3246 #define NC_IdxExpr   0x000020 /* True if resolving columns of CREATE INDEX */
3247 #define NC_SelfRef   0x00002e /* Combo: PartIdx, isCheck, GenCol, and IdxExpr */
3248 #define NC_VarSelect 0x000040 /* A correlated subquery has been seen */
3249 #define NC_UEList    0x000080 /* True if uNC.pEList is used */
3250 #define NC_UAggInfo  0x000100 /* True if uNC.pAggInfo is used */
3251 #define NC_UUpsert   0x000200 /* True if uNC.pUpsert is used */
3252 #define NC_UBaseReg  0x000400 /* True if uNC.iBaseReg is used */
3253 #define NC_MinMaxAgg 0x001000 /* min/max aggregates seen.  See note above */
3254 #define NC_Complex   0x002000 /* True if a function or subquery seen */
3255 #define NC_AllowWin  0x004000 /* Window functions are allowed here */
3256 #define NC_HasWin    0x008000 /* One or more window functions seen */
3257 #define NC_IsDDL     0x010000 /* Resolving names in a CREATE statement */
3258 #define NC_InAggFunc 0x020000 /* True if analyzing arguments to an agg func */
3259 #define NC_FromDDL   0x040000 /* SQL text comes from sqlite_schema */
3260 #define NC_NoSelect  0x080000 /* Do not descend into sub-selects */
3261 #define NC_OrderAgg 0x8000000 /* Has an aggregate other than count/min/max */
3262 
3263 /*
3264 ** An instance of the following object describes a single ON CONFLICT
3265 ** clause in an upsert.
3266 **
3267 ** The pUpsertTarget field is only set if the ON CONFLICT clause includes
3268 ** conflict-target clause.  (In "ON CONFLICT(a,b)" the "(a,b)" is the
3269 ** conflict-target clause.)  The pUpsertTargetWhere is the optional
3270 ** WHERE clause used to identify partial unique indexes.
3271 **
3272 ** pUpsertSet is the list of column=expr terms of the UPDATE statement.
3273 ** The pUpsertSet field is NULL for a ON CONFLICT DO NOTHING.  The
3274 ** pUpsertWhere is the WHERE clause for the UPDATE and is NULL if the
3275 ** WHERE clause is omitted.
3276 */
3277 struct Upsert {
3278   ExprList *pUpsertTarget;  /* Optional description of conflict target */
3279   Expr *pUpsertTargetWhere; /* WHERE clause for partial index targets */
3280   ExprList *pUpsertSet;     /* The SET clause from an ON CONFLICT UPDATE */
3281   Expr *pUpsertWhere;       /* WHERE clause for the ON CONFLICT UPDATE */
3282   Upsert *pNextUpsert;      /* Next ON CONFLICT clause in the list */
3283   u8 isDoUpdate;            /* True for DO UPDATE.  False for DO NOTHING */
3284   /* Above this point is the parse tree for the ON CONFLICT clauses.
3285   ** The next group of fields stores intermediate data. */
3286   void *pToFree;            /* Free memory when deleting the Upsert object */
3287   /* All fields above are owned by the Upsert object and must be freed
3288   ** when the Upsert is destroyed.  The fields below are used to transfer
3289   ** information from the INSERT processing down into the UPDATE processing
3290   ** while generating code.  The fields below are owned by the INSERT
3291   ** statement and will be freed by INSERT processing. */
3292   Index *pUpsertIdx;        /* UNIQUE constraint specified by pUpsertTarget */
3293   SrcList *pUpsertSrc;      /* Table to be updated */
3294   int regData;              /* First register holding array of VALUES */
3295   int iDataCur;             /* Index of the data cursor */
3296   int iIdxCur;              /* Index of the first index cursor */
3297 };
3298 
3299 /*
3300 ** An instance of the following structure contains all information
3301 ** needed to generate code for a single SELECT statement.
3302 **
3303 ** See the header comment on the computeLimitRegisters() routine for a
3304 ** detailed description of the meaning of the iLimit and iOffset fields.
3305 **
3306 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
3307 ** These addresses must be stored so that we can go back and fill in
3308 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
3309 ** the number of columns in P2 can be computed at the same time
3310 ** as the OP_OpenEphm instruction is coded because not
3311 ** enough information about the compound query is known at that point.
3312 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
3313 ** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
3314 ** sequences for the ORDER BY clause.
3315 */
3316 struct Select {
3317   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
3318   LogEst nSelectRow;     /* Estimated number of result rows */
3319   u32 selFlags;          /* Various SF_* values */
3320   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
3321   u32 selId;             /* Unique identifier number for this SELECT */
3322   int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
3323   ExprList *pEList;      /* The fields of the result */
3324   SrcList *pSrc;         /* The FROM clause */
3325   Expr *pWhere;          /* The WHERE clause */
3326   ExprList *pGroupBy;    /* The GROUP BY clause */
3327   Expr *pHaving;         /* The HAVING clause */
3328   ExprList *pOrderBy;    /* The ORDER BY clause */
3329   Select *pPrior;        /* Prior select in a compound select statement */
3330   Select *pNext;         /* Next select to the left in a compound */
3331   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
3332   With *pWith;           /* WITH clause attached to this select. Or NULL. */
3333 #ifndef SQLITE_OMIT_WINDOWFUNC
3334   Window *pWin;          /* List of window functions */
3335   Window *pWinDefn;      /* List of named window definitions */
3336 #endif
3337 };
3338 
3339 /*
3340 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
3341 ** "Select Flag".
3342 **
3343 ** Value constraints (all checked via assert())
3344 **     SF_HasAgg      == NC_HasAgg
3345 **     SF_MinMaxAgg   == NC_MinMaxAgg     == SQLITE_FUNC_MINMAX
3346 **     SF_OrderByReqd == NC_OrderAgg      == SQLITE_FUNC_ANYORDER
3347 **     SF_FixedLimit  == WHERE_USE_LIMIT
3348 */
3349 #define SF_Distinct      0x0000001 /* Output should be DISTINCT */
3350 #define SF_All           0x0000002 /* Includes the ALL keyword */
3351 #define SF_Resolved      0x0000004 /* Identifiers have been resolved */
3352 #define SF_Aggregate     0x0000008 /* Contains agg functions or a GROUP BY */
3353 #define SF_HasAgg        0x0000010 /* Contains aggregate functions */
3354 #define SF_UsesEphemeral 0x0000020 /* Uses the OpenEphemeral opcode */
3355 #define SF_Expanded      0x0000040 /* sqlite3SelectExpand() called on this */
3356 #define SF_HasTypeInfo   0x0000080 /* FROM subqueries have Table metadata */
3357 #define SF_Compound      0x0000100 /* Part of a compound query */
3358 #define SF_Values        0x0000200 /* Synthesized from VALUES clause */
3359 #define SF_MultiValue    0x0000400 /* Single VALUES term with multiple rows */
3360 #define SF_NestedFrom    0x0000800 /* Part of a parenthesized FROM clause */
3361 #define SF_MinMaxAgg     0x0001000 /* Aggregate containing min() or max() */
3362 #define SF_Recursive     0x0002000 /* The recursive part of a recursive CTE */
3363 #define SF_FixedLimit    0x0004000 /* nSelectRow set by a constant LIMIT */
3364 #define SF_MaybeConvert  0x0008000 /* Need convertCompoundSelectToSubquery() */
3365 #define SF_Converted     0x0010000 /* By convertCompoundSelectToSubquery() */
3366 #define SF_IncludeHidden 0x0020000 /* Include hidden columns in output */
3367 #define SF_ComplexResult 0x0040000 /* Result contains subquery or function */
3368 #define SF_WhereBegin    0x0080000 /* Really a WhereBegin() call.  Debug Only */
3369 #define SF_WinRewrite    0x0100000 /* Window function rewrite accomplished */
3370 #define SF_View          0x0200000 /* SELECT statement is a view */
3371 #define SF_NoopOrderBy   0x0400000 /* ORDER BY is ignored for this query */
3372 #define SF_UFSrcCheck    0x0800000 /* Check pSrc as required by UPDATE...FROM */
3373 #define SF_PushDown      0x1000000 /* SELECT has be modified by push-down opt */
3374 #define SF_MultiPart     0x2000000 /* Has multiple incompatible PARTITIONs */
3375 #define SF_CopyCte       0x4000000 /* SELECT statement is a copy of a CTE */
3376 #define SF_OrderByReqd   0x8000000 /* The ORDER BY clause may not be omitted */
3377 
3378 /* True if S exists and has SF_NestedFrom */
3379 #define IsNestedFrom(S) ((S)!=0 && ((S)->selFlags&SF_NestedFrom)!=0)
3380 
3381 /*
3382 ** The results of a SELECT can be distributed in several ways, as defined
3383 ** by one of the following macros.  The "SRT" prefix means "SELECT Result
3384 ** Type".
3385 **
3386 **     SRT_Union       Store results as a key in a temporary index
3387 **                     identified by pDest->iSDParm.
3388 **
3389 **     SRT_Except      Remove results from the temporary index pDest->iSDParm.
3390 **
3391 **     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
3392 **                     set is not empty.
3393 **
3394 **     SRT_Discard     Throw the results away.  This is used by SELECT
3395 **                     statements within triggers whose only purpose is
3396 **                     the side-effects of functions.
3397 **
3398 **     SRT_Output      Generate a row of output (using the OP_ResultRow
3399 **                     opcode) for each row in the result set.
3400 **
3401 **     SRT_Mem         Only valid if the result is a single column.
3402 **                     Store the first column of the first result row
3403 **                     in register pDest->iSDParm then abandon the rest
3404 **                     of the query.  This destination implies "LIMIT 1".
3405 **
3406 **     SRT_Set         The result must be a single column.  Store each
3407 **                     row of result as the key in table pDest->iSDParm.
3408 **                     Apply the affinity pDest->affSdst before storing
3409 **                     results.  Used to implement "IN (SELECT ...)".
3410 **
3411 **     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
3412 **                     the result there. The cursor is left open after
3413 **                     returning.  This is like SRT_Table except that
3414 **                     this destination uses OP_OpenEphemeral to create
3415 **                     the table first.
3416 **
3417 **     SRT_Coroutine   Generate a co-routine that returns a new row of
3418 **                     results each time it is invoked.  The entry point
3419 **                     of the co-routine is stored in register pDest->iSDParm
3420 **                     and the result row is stored in pDest->nDest registers
3421 **                     starting with pDest->iSdst.
3422 **
3423 **     SRT_Table       Store results in temporary table pDest->iSDParm.
3424 **     SRT_Fifo        This is like SRT_EphemTab except that the table
3425 **                     is assumed to already be open.  SRT_Fifo has
3426 **                     the additional property of being able to ignore
3427 **                     the ORDER BY clause.
3428 **
3429 **     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
3430 **                     But also use temporary table pDest->iSDParm+1 as
3431 **                     a record of all prior results and ignore any duplicate
3432 **                     rows.  Name means:  "Distinct Fifo".
3433 **
3434 **     SRT_Queue       Store results in priority queue pDest->iSDParm (really
3435 **                     an index).  Append a sequence number so that all entries
3436 **                     are distinct.
3437 **
3438 **     SRT_DistQueue   Store results in priority queue pDest->iSDParm only if
3439 **                     the same record has never been stored before.  The
3440 **                     index at pDest->iSDParm+1 hold all prior stores.
3441 **
3442 **     SRT_Upfrom      Store results in the temporary table already opened by
3443 **                     pDest->iSDParm. If (pDest->iSDParm<0), then the temp
3444 **                     table is an intkey table - in this case the first
3445 **                     column returned by the SELECT is used as the integer
3446 **                     key. If (pDest->iSDParm>0), then the table is an index
3447 **                     table. (pDest->iSDParm) is the number of key columns in
3448 **                     each index record in this case.
3449 */
3450 #define SRT_Union        1  /* Store result as keys in an index */
3451 #define SRT_Except       2  /* Remove result from a UNION index */
3452 #define SRT_Exists       3  /* Store 1 if the result is not empty */
3453 #define SRT_Discard      4  /* Do not save the results anywhere */
3454 #define SRT_DistFifo     5  /* Like SRT_Fifo, but unique results only */
3455 #define SRT_DistQueue    6  /* Like SRT_Queue, but unique results only */
3456 
3457 /* The DISTINCT clause is ignored for all of the above.  Not that
3458 ** IgnorableDistinct() implies IgnorableOrderby() */
3459 #define IgnorableDistinct(X) ((X->eDest)<=SRT_DistQueue)
3460 
3461 #define SRT_Queue        7  /* Store result in an queue */
3462 #define SRT_Fifo         8  /* Store result as data with an automatic rowid */
3463 
3464 /* The ORDER BY clause is ignored for all of the above */
3465 #define IgnorableOrderby(X) ((X->eDest)<=SRT_Fifo)
3466 
3467 #define SRT_Output       9  /* Output each row of result */
3468 #define SRT_Mem         10  /* Store result in a memory cell */
3469 #define SRT_Set         11  /* Store results as keys in an index */
3470 #define SRT_EphemTab    12  /* Create transient tab and store like SRT_Table */
3471 #define SRT_Coroutine   13  /* Generate a single row of result */
3472 #define SRT_Table       14  /* Store result as data with an automatic rowid */
3473 #define SRT_Upfrom      15  /* Store result as data with rowid */
3474 
3475 /*
3476 ** An instance of this object describes where to put of the results of
3477 ** a SELECT statement.
3478 */
3479 struct SelectDest {
3480   u8 eDest;            /* How to dispose of the results.  One of SRT_* above. */
3481   int iSDParm;         /* A parameter used by the eDest disposal method */
3482   int iSDParm2;        /* A second parameter for the eDest disposal method */
3483   int iSdst;           /* Base register where results are written */
3484   int nSdst;           /* Number of registers allocated */
3485   char *zAffSdst;      /* Affinity used when eDest==SRT_Set */
3486   ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
3487 };
3488 
3489 /*
3490 ** During code generation of statements that do inserts into AUTOINCREMENT
3491 ** tables, the following information is attached to the Table.u.autoInc.p
3492 ** pointer of each autoincrement table to record some side information that
3493 ** the code generator needs.  We have to keep per-table autoincrement
3494 ** information in case inserts are done within triggers.  Triggers do not
3495 ** normally coordinate their activities, but we do need to coordinate the
3496 ** loading and saving of autoincrement information.
3497 */
3498 struct AutoincInfo {
3499   AutoincInfo *pNext;   /* Next info block in a list of them all */
3500   Table *pTab;          /* Table this info block refers to */
3501   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
3502   int regCtr;           /* Memory register holding the rowid counter */
3503 };
3504 
3505 /*
3506 ** At least one instance of the following structure is created for each
3507 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
3508 ** statement. All such objects are stored in the linked list headed at
3509 ** Parse.pTriggerPrg and deleted once statement compilation has been
3510 ** completed.
3511 **
3512 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
3513 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
3514 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
3515 ** The Parse.pTriggerPrg list never contains two entries with the same
3516 ** values for both pTrigger and orconf.
3517 **
3518 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
3519 ** accessed (or set to 0 for triggers fired as a result of INSERT
3520 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
3521 ** a mask of new.* columns used by the program.
3522 */
3523 struct TriggerPrg {
3524   Trigger *pTrigger;      /* Trigger this program was coded from */
3525   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
3526   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
3527   int orconf;             /* Default ON CONFLICT policy */
3528   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
3529 };
3530 
3531 /*
3532 ** The yDbMask datatype for the bitmask of all attached databases.
3533 */
3534 #if SQLITE_MAX_ATTACHED>30
3535   typedef unsigned char yDbMask[(SQLITE_MAX_ATTACHED+9)/8];
3536 # define DbMaskTest(M,I)    (((M)[(I)/8]&(1<<((I)&7)))!=0)
3537 # define DbMaskZero(M)      memset((M),0,sizeof(M))
3538 # define DbMaskSet(M,I)     (M)[(I)/8]|=(1<<((I)&7))
3539 # define DbMaskAllZero(M)   sqlite3DbMaskAllZero(M)
3540 # define DbMaskNonZero(M)   (sqlite3DbMaskAllZero(M)==0)
3541 #else
3542   typedef unsigned int yDbMask;
3543 # define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
3544 # define DbMaskZero(M)      (M)=0
3545 # define DbMaskSet(M,I)     (M)|=(((yDbMask)1)<<(I))
3546 # define DbMaskAllZero(M)   (M)==0
3547 # define DbMaskNonZero(M)   (M)!=0
3548 #endif
3549 
3550 /*
3551 ** An instance of the ParseCleanup object specifies an operation that
3552 ** should be performed after parsing to deallocation resources obtained
3553 ** during the parse and which are no longer needed.
3554 */
3555 struct ParseCleanup {
3556   ParseCleanup *pNext;               /* Next cleanup task */
3557   void *pPtr;                        /* Pointer to object to deallocate */
3558   void (*xCleanup)(sqlite3*,void*);  /* Deallocation routine */
3559 };
3560 
3561 /*
3562 ** An SQL parser context.  A copy of this structure is passed through
3563 ** the parser and down into all the parser action routine in order to
3564 ** carry around information that is global to the entire parse.
3565 **
3566 ** The structure is divided into two parts.  When the parser and code
3567 ** generate call themselves recursively, the first part of the structure
3568 ** is constant but the second part is reset at the beginning and end of
3569 ** each recursion.
3570 **
3571 ** The nTableLock and aTableLock variables are only used if the shared-cache
3572 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
3573 ** used to store the set of table-locks required by the statement being
3574 ** compiled. Function sqlite3TableLock() is used to add entries to the
3575 ** list.
3576 */
3577 struct Parse {
3578   sqlite3 *db;         /* The main database structure */
3579   char *zErrMsg;       /* An error message */
3580   Vdbe *pVdbe;         /* An engine for executing database bytecode */
3581   int rc;              /* Return code from execution */
3582   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
3583   u8 checkSchema;      /* Causes schema cookie check after an error */
3584   u8 nested;           /* Number of nested calls to the parser/code generator */
3585   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
3586   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
3587   u8 mayAbort;         /* True if statement may throw an ABORT exception */
3588   u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
3589   u8 okConstFactor;    /* OK to factor out constants */
3590   u8 disableLookaside; /* Number of times lookaside has been disabled */
3591   u8 disableVtab;      /* Disable all virtual tables for this parse */
3592   u8 withinRJSubrtn;   /* Nesting level for RIGHT JOIN body subroutines */
3593 #if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
3594   u8 earlyCleanup;     /* OOM inside sqlite3ParserAddCleanup() */
3595 #endif
3596   int nRangeReg;       /* Size of the temporary register block */
3597   int iRangeReg;       /* First register in temporary register block */
3598   int nErr;            /* Number of errors seen */
3599   int nTab;            /* Number of previously allocated VDBE cursors */
3600   int nMem;            /* Number of memory cells used so far */
3601   int szOpAlloc;       /* Bytes of memory space allocated for Vdbe.aOp[] */
3602   int iSelfTab;        /* Table associated with an index on expr, or negative
3603                        ** of the base register during check-constraint eval */
3604   int nLabel;          /* The *negative* of the number of labels used */
3605   int nLabelAlloc;     /* Number of slots in aLabel */
3606   int *aLabel;         /* Space to hold the labels */
3607   ExprList *pConstExpr;/* Constant expressions */
3608   Token constraintName;/* Name of the constraint currently being parsed */
3609   yDbMask writeMask;   /* Start a write transaction on these databases */
3610   yDbMask cookieMask;  /* Bitmask of schema verified databases */
3611   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
3612   int regRoot;         /* Register holding root page number for new objects */
3613   int nMaxArg;         /* Max args passed to user function by sub-program */
3614   int nSelect;         /* Number of SELECT stmts. Counter for Select.selId */
3615 #ifndef SQLITE_OMIT_SHARED_CACHE
3616   int nTableLock;        /* Number of locks in aTableLock */
3617   TableLock *aTableLock; /* Required table locks for shared-cache mode */
3618 #endif
3619   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
3620   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
3621   Table *pTriggerTab;  /* Table triggers are being coded for */
3622   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
3623   ParseCleanup *pCleanup;   /* List of cleanup operations to run after parse */
3624   union {
3625     int addrCrTab;         /* Address of OP_CreateBtree on CREATE TABLE */
3626     Returning *pReturning; /* The RETURNING clause */
3627   } u1;
3628   u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
3629   u32 oldmask;         /* Mask of old.* columns referenced */
3630   u32 newmask;         /* Mask of new.* columns referenced */
3631   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
3632   u8 bReturning;       /* Coding a RETURNING trigger */
3633   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
3634   u8 disableTriggers;  /* True to disable triggers */
3635 
3636   /**************************************************************************
3637   ** Fields above must be initialized to zero.  The fields that follow,
3638   ** down to the beginning of the recursive section, do not need to be
3639   ** initialized as they will be set before being used.  The boundary is
3640   ** determined by offsetof(Parse,aTempReg).
3641   **************************************************************************/
3642 
3643   int aTempReg[8];        /* Holding area for temporary registers */
3644   Parse *pOuterParse;     /* Outer Parse object when nested */
3645   Token sNameToken;       /* Token with unqualified schema object name */
3646 
3647   /************************************************************************
3648   ** Above is constant between recursions.  Below is reset before and after
3649   ** each recursion.  The boundary between these two regions is determined
3650   ** using offsetof(Parse,sLastToken) so the sLastToken field must be the
3651   ** first field in the recursive region.
3652   ************************************************************************/
3653 
3654   Token sLastToken;       /* The last token parsed */
3655   ynVar nVar;               /* Number of '?' variables seen in the SQL so far */
3656   u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
3657   u8 explain;               /* True if the EXPLAIN flag is found on the query */
3658   u8 eParseMode;            /* PARSE_MODE_XXX constant */
3659 #ifndef SQLITE_OMIT_VIRTUALTABLE
3660   int nVtabLock;            /* Number of virtual tables to lock */
3661 #endif
3662   int nHeight;              /* Expression tree height of current sub-select */
3663 #ifndef SQLITE_OMIT_EXPLAIN
3664   int addrExplain;          /* Address of current OP_Explain opcode */
3665 #endif
3666   VList *pVList;            /* Mapping between variable names and numbers */
3667   Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
3668   const char *zTail;        /* All SQL text past the last semicolon parsed */
3669   Table *pNewTable;         /* A table being constructed by CREATE TABLE */
3670   Index *pNewIndex;         /* An index being constructed by CREATE INDEX.
3671                             ** Also used to hold redundant UNIQUE constraints
3672                             ** during a RENAME COLUMN */
3673   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
3674   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
3675 #ifndef SQLITE_OMIT_VIRTUALTABLE
3676   Token sArg;               /* Complete text of a module argument */
3677   Table **apVtabLock;       /* Pointer to virtual tables needing locking */
3678 #endif
3679   With *pWith;              /* Current WITH clause, or NULL */
3680 #ifndef SQLITE_OMIT_ALTERTABLE
3681   RenameToken *pRename;     /* Tokens subject to renaming by ALTER TABLE */
3682 #endif
3683 };
3684 
3685 /* Allowed values for Parse.eParseMode
3686 */
3687 #define PARSE_MODE_NORMAL        0
3688 #define PARSE_MODE_DECLARE_VTAB  1
3689 #define PARSE_MODE_RENAME        2
3690 #define PARSE_MODE_UNMAP         3
3691 
3692 /*
3693 ** Sizes and pointers of various parts of the Parse object.
3694 */
3695 #define PARSE_HDR(X)  (((char*)(X))+offsetof(Parse,zErrMsg))
3696 #define PARSE_HDR_SZ (offsetof(Parse,aTempReg)-offsetof(Parse,zErrMsg)) /* Recursive part w/o aColCache*/
3697 #define PARSE_RECURSE_SZ offsetof(Parse,sLastToken)    /* Recursive part */
3698 #define PARSE_TAIL_SZ (sizeof(Parse)-PARSE_RECURSE_SZ) /* Non-recursive part */
3699 #define PARSE_TAIL(X) (((char*)(X))+PARSE_RECURSE_SZ)  /* Pointer to tail */
3700 
3701 /*
3702 ** Return true if currently inside an sqlite3_declare_vtab() call.
3703 */
3704 #ifdef SQLITE_OMIT_VIRTUALTABLE
3705   #define IN_DECLARE_VTAB 0
3706 #else
3707   #define IN_DECLARE_VTAB (pParse->eParseMode==PARSE_MODE_DECLARE_VTAB)
3708 #endif
3709 
3710 #if defined(SQLITE_OMIT_ALTERTABLE)
3711   #define IN_RENAME_OBJECT 0
3712 #else
3713   #define IN_RENAME_OBJECT (pParse->eParseMode>=PARSE_MODE_RENAME)
3714 #endif
3715 
3716 #if defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_OMIT_ALTERTABLE)
3717   #define IN_SPECIAL_PARSE 0
3718 #else
3719   #define IN_SPECIAL_PARSE (pParse->eParseMode!=PARSE_MODE_NORMAL)
3720 #endif
3721 
3722 /*
3723 ** An instance of the following structure can be declared on a stack and used
3724 ** to save the Parse.zAuthContext value so that it can be restored later.
3725 */
3726 struct AuthContext {
3727   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
3728   Parse *pParse;              /* The Parse structure */
3729 };
3730 
3731 /*
3732 ** Bitfield flags for P5 value in various opcodes.
3733 **
3734 ** Value constraints (enforced via assert()):
3735 **    OPFLAG_LENGTHARG    == SQLITE_FUNC_LENGTH
3736 **    OPFLAG_TYPEOFARG    == SQLITE_FUNC_TYPEOF
3737 **    OPFLAG_BULKCSR      == BTREE_BULKLOAD
3738 **    OPFLAG_SEEKEQ       == BTREE_SEEK_EQ
3739 **    OPFLAG_FORDELETE    == BTREE_FORDELETE
3740 **    OPFLAG_SAVEPOSITION == BTREE_SAVEPOSITION
3741 **    OPFLAG_AUXDELETE    == BTREE_AUXDELETE
3742 */
3743 #define OPFLAG_NCHANGE       0x01    /* OP_Insert: Set to update db->nChange */
3744                                      /* Also used in P2 (not P5) of OP_Delete */
3745 #define OPFLAG_NOCHNG        0x01    /* OP_VColumn nochange for UPDATE */
3746 #define OPFLAG_EPHEM         0x01    /* OP_Column: Ephemeral output is ok */
3747 #define OPFLAG_LASTROWID     0x20    /* Set to update db->lastRowid */
3748 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
3749 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
3750 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
3751 #define OPFLAG_ISNOOP        0x40    /* OP_Delete does pre-update-hook only */
3752 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
3753 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
3754 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
3755 #define OPFLAG_SEEKEQ        0x02    /* OP_Open** cursor uses EQ seek only */
3756 #define OPFLAG_FORDELETE     0x08    /* OP_Open should use BTREE_FORDELETE */
3757 #define OPFLAG_P2ISREG       0x10    /* P2 to OP_Open** is a register number */
3758 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
3759 #define OPFLAG_SAVEPOSITION  0x02    /* OP_Delete/Insert: save cursor pos */
3760 #define OPFLAG_AUXDELETE     0x04    /* OP_Delete: index in a DELETE op */
3761 #define OPFLAG_NOCHNG_MAGIC  0x6d    /* OP_MakeRecord: serialtype 10 is ok */
3762 #define OPFLAG_PREFORMAT     0x80    /* OP_Insert uses preformatted cell */
3763 
3764 /*
3765 ** Each trigger present in the database schema is stored as an instance of
3766 ** struct Trigger.
3767 **
3768 ** Pointers to instances of struct Trigger are stored in two ways.
3769 ** 1. In the "trigHash" hash table (part of the sqlite3* that represents the
3770 **    database). This allows Trigger structures to be retrieved by name.
3771 ** 2. All triggers associated with a single table form a linked list, using the
3772 **    pNext member of struct Trigger. A pointer to the first element of the
3773 **    linked list is stored as the "pTrigger" member of the associated
3774 **    struct Table.
3775 **
3776 ** The "step_list" member points to the first element of a linked list
3777 ** containing the SQL statements specified as the trigger program.
3778 */
3779 struct Trigger {
3780   char *zName;            /* The name of the trigger                        */
3781   char *table;            /* The table or view to which the trigger applies */
3782   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
3783   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
3784   u8 bReturning;          /* This trigger implements a RETURNING clause */
3785   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
3786   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
3787                              the <column-list> is stored here */
3788   Schema *pSchema;        /* Schema containing the trigger */
3789   Schema *pTabSchema;     /* Schema containing the table */
3790   TriggerStep *step_list; /* Link list of trigger program steps             */
3791   Trigger *pNext;         /* Next trigger associated with the table */
3792 };
3793 
3794 /*
3795 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
3796 ** determine which.
3797 **
3798 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
3799 ** In that cases, the constants below can be ORed together.
3800 */
3801 #define TRIGGER_BEFORE  1
3802 #define TRIGGER_AFTER   2
3803 
3804 /*
3805 ** An instance of struct TriggerStep is used to store a single SQL statement
3806 ** that is a part of a trigger-program.
3807 **
3808 ** Instances of struct TriggerStep are stored in a singly linked list (linked
3809 ** using the "pNext" member) referenced by the "step_list" member of the
3810 ** associated struct Trigger instance. The first element of the linked list is
3811 ** the first step of the trigger-program.
3812 **
3813 ** The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
3814 ** "SELECT" statement. The meanings of the other members is determined by the
3815 ** value of "op" as follows:
3816 **
3817 ** (op == TK_INSERT)
3818 ** orconf    -> stores the ON CONFLICT algorithm
3819 ** pSelect   -> The content to be inserted - either a SELECT statement or
3820 **              a VALUES clause.
3821 ** zTarget   -> Dequoted name of the table to insert into.
3822 ** pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
3823 **              statement, then this stores the column-names to be
3824 **              inserted into.
3825 ** pUpsert   -> The ON CONFLICT clauses for an Upsert
3826 **
3827 ** (op == TK_DELETE)
3828 ** zTarget   -> Dequoted name of the table to delete from.
3829 ** pWhere    -> The WHERE clause of the DELETE statement if one is specified.
3830 **              Otherwise NULL.
3831 **
3832 ** (op == TK_UPDATE)
3833 ** zTarget   -> Dequoted name of the table to update.
3834 ** pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
3835 **              Otherwise NULL.
3836 ** pExprList -> A list of the columns to update and the expressions to update
3837 **              them to. See sqlite3Update() documentation of "pChanges"
3838 **              argument.
3839 **
3840 ** (op == TK_SELECT)
3841 ** pSelect   -> The SELECT statement
3842 **
3843 ** (op == TK_RETURNING)
3844 ** pExprList -> The list of expressions that follow the RETURNING keyword.
3845 **
3846 */
3847 struct TriggerStep {
3848   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT,
3849                        ** or TK_RETURNING */
3850   u8 orconf;           /* OE_Rollback etc. */
3851   Trigger *pTrig;      /* The trigger that this step is a part of */
3852   Select *pSelect;     /* SELECT statement or RHS of INSERT INTO SELECT ... */
3853   char *zTarget;       /* Target table for DELETE, UPDATE, INSERT */
3854   SrcList *pFrom;      /* FROM clause for UPDATE statement (if any) */
3855   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
3856   ExprList *pExprList; /* SET clause for UPDATE, or RETURNING clause */
3857   IdList *pIdList;     /* Column names for INSERT */
3858   Upsert *pUpsert;     /* Upsert clauses on an INSERT */
3859   char *zSpan;         /* Original SQL text of this command */
3860   TriggerStep *pNext;  /* Next in the link-list */
3861   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
3862 };
3863 
3864 /*
3865 ** Information about a RETURNING clause
3866 */
3867 struct Returning {
3868   Parse *pParse;        /* The parse that includes the RETURNING clause */
3869   ExprList *pReturnEL;  /* List of expressions to return */
3870   Trigger retTrig;      /* The transient trigger that implements RETURNING */
3871   TriggerStep retTStep; /* The trigger step */
3872   int iRetCur;          /* Transient table holding RETURNING results */
3873   int nRetCol;          /* Number of in pReturnEL after expansion */
3874   int iRetReg;          /* Register array for holding a row of RETURNING */
3875 };
3876 
3877 /*
3878 ** An objected used to accumulate the text of a string where we
3879 ** do not necessarily know how big the string will be in the end.
3880 */
3881 struct sqlite3_str {
3882   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
3883   char *zText;         /* The string collected so far */
3884   u32  nAlloc;         /* Amount of space allocated in zText */
3885   u32  mxAlloc;        /* Maximum allowed allocation.  0 for no malloc usage */
3886   u32  nChar;          /* Length of the string so far */
3887   u8   accError;       /* SQLITE_NOMEM or SQLITE_TOOBIG */
3888   u8   printfFlags;    /* SQLITE_PRINTF flags below */
3889 };
3890 #define SQLITE_PRINTF_INTERNAL 0x01  /* Internal-use-only converters allowed */
3891 #define SQLITE_PRINTF_SQLFUNC  0x02  /* SQL function arguments to VXPrintf */
3892 #define SQLITE_PRINTF_MALLOCED 0x04  /* True if xText is allocated space */
3893 
3894 #define isMalloced(X)  (((X)->printfFlags & SQLITE_PRINTF_MALLOCED)!=0)
3895 
3896 
3897 /*
3898 ** A pointer to this structure is used to communicate information
3899 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
3900 */
3901 typedef struct {
3902   sqlite3 *db;        /* The database being initialized */
3903   char **pzErrMsg;    /* Error message stored here */
3904   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
3905   int rc;             /* Result code stored here */
3906   u32 mInitFlags;     /* Flags controlling error messages */
3907   u32 nInitRow;       /* Number of rows processed */
3908   Pgno mxPage;        /* Maximum page number.  0 for no limit. */
3909 } InitData;
3910 
3911 /*
3912 ** Allowed values for mInitFlags
3913 */
3914 #define INITFLAG_AlterMask     0x0003  /* Types of ALTER */
3915 #define INITFLAG_AlterRename   0x0001  /* Reparse after a RENAME */
3916 #define INITFLAG_AlterDrop     0x0002  /* Reparse after a DROP COLUMN */
3917 #define INITFLAG_AlterAdd      0x0003  /* Reparse after an ADD COLUMN */
3918 
3919 /* Tuning parameters are set using SQLITE_TESTCTRL_TUNE and are controlled
3920 ** on debug-builds of the CLI using ".testctrl tune ID VALUE".  Tuning
3921 ** parameters are for temporary use during development, to help find
3922 ** optimial values for parameters in the query planner.  The should not
3923 ** be used on trunk check-ins.  They are a temporary mechanism available
3924 ** for transient development builds only.
3925 **
3926 ** Tuning parameters are numbered starting with 1.
3927 */
3928 #define SQLITE_NTUNE  6             /* Should be zero for all trunk check-ins */
3929 #ifdef SQLITE_DEBUG
3930 # define Tuning(X)  (sqlite3Config.aTune[(X)-1])
3931 #else
3932 # define Tuning(X)  0
3933 #endif
3934 
3935 /*
3936 ** Structure containing global configuration data for the SQLite library.
3937 **
3938 ** This structure also contains some state information.
3939 */
3940 struct Sqlite3Config {
3941   int bMemstat;                     /* True to enable memory status */
3942   u8 bCoreMutex;                    /* True to enable core mutexing */
3943   u8 bFullMutex;                    /* True to enable full mutexing */
3944   u8 bOpenUri;                      /* True to interpret filenames as URIs */
3945   u8 bUseCis;                       /* Use covering indices for full-scans */
3946   u8 bSmallMalloc;                  /* Avoid large memory allocations if true */
3947   u8 bExtraSchemaChecks;            /* Verify type,name,tbl_name in schema */
3948   int mxStrlen;                     /* Maximum string length */
3949   int neverCorrupt;                 /* Database is always well-formed */
3950   int szLookaside;                  /* Default lookaside buffer size */
3951   int nLookaside;                   /* Default lookaside buffer count */
3952   int nStmtSpill;                   /* Stmt-journal spill-to-disk threshold */
3953   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
3954   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
3955   sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
3956   void *pHeap;                      /* Heap storage space */
3957   int nHeap;                        /* Size of pHeap[] */
3958   int mnReq, mxReq;                 /* Min and max heap requests sizes */
3959   sqlite3_int64 szMmap;             /* mmap() space per open file */
3960   sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
3961   void *pPage;                      /* Page cache memory */
3962   int szPage;                       /* Size of each page in pPage[] */
3963   int nPage;                        /* Number of pages in pPage[] */
3964   int mxParserStack;                /* maximum depth of the parser stack */
3965   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
3966   u32 szPma;                        /* Maximum Sorter PMA size */
3967   /* The above might be initialized to non-zero.  The following need to always
3968   ** initially be zero, however. */
3969   int isInit;                       /* True after initialization has finished */
3970   int inProgress;                   /* True while initialization in progress */
3971   int isMutexInit;                  /* True after mutexes are initialized */
3972   int isMallocInit;                 /* True after malloc is initialized */
3973   int isPCacheInit;                 /* True after malloc is initialized */
3974   int nRefInitMutex;                /* Number of users of pInitMutex */
3975   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
3976   void (*xLog)(void*,int,const char*); /* Function for logging */
3977   void *pLogArg;                       /* First argument to xLog() */
3978 #ifdef SQLITE_ENABLE_SQLLOG
3979   void(*xSqllog)(void*,sqlite3*,const char*, int);
3980   void *pSqllogArg;
3981 #endif
3982 #ifdef SQLITE_VDBE_COVERAGE
3983   /* The following callback (if not NULL) is invoked on every VDBE branch
3984   ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
3985   */
3986   void (*xVdbeBranch)(void*,unsigned iSrcLine,u8 eThis,u8 eMx);  /* Callback */
3987   void *pVdbeBranchArg;                                     /* 1st argument */
3988 #endif
3989 #ifndef SQLITE_OMIT_DESERIALIZE
3990   sqlite3_int64 mxMemdbSize;        /* Default max memdb size */
3991 #endif
3992 #ifndef SQLITE_UNTESTABLE
3993   int (*xTestCallback)(int);        /* Invoked by sqlite3FaultSim() */
3994 #endif
3995   int bLocaltimeFault;              /* True to fail localtime() calls */
3996   int (*xAltLocaltime)(const void*,void*); /* Alternative localtime() routine */
3997   int iOnceResetThreshold;          /* When to reset OP_Once counters */
3998   u32 szSorterRef;                  /* Min size in bytes to use sorter-refs */
3999   unsigned int iPrngSeed;           /* Alternative fixed seed for the PRNG */
4000   /* vvvv--- must be last ---vvv */
4001 #ifdef SQLITE_DEBUG
4002   sqlite3_int64 aTune[SQLITE_NTUNE]; /* Tuning parameters */
4003 #endif
4004 };
4005 
4006 /*
4007 ** This macro is used inside of assert() statements to indicate that
4008 ** the assert is only valid on a well-formed database.  Instead of:
4009 **
4010 **     assert( X );
4011 **
4012 ** One writes:
4013 **
4014 **     assert( X || CORRUPT_DB );
4015 **
4016 ** CORRUPT_DB is true during normal operation.  CORRUPT_DB does not indicate
4017 ** that the database is definitely corrupt, only that it might be corrupt.
4018 ** For most test cases, CORRUPT_DB is set to false using a special
4019 ** sqlite3_test_control().  This enables assert() statements to prove
4020 ** things that are always true for well-formed databases.
4021 */
4022 #define CORRUPT_DB  (sqlite3Config.neverCorrupt==0)
4023 
4024 /*
4025 ** Context pointer passed down through the tree-walk.
4026 */
4027 struct Walker {
4028   Parse *pParse;                            /* Parser context.  */
4029   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
4030   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
4031   void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
4032   int walkerDepth;                          /* Number of subqueries */
4033   u16 eCode;                                /* A small processing code */
4034   union {                                   /* Extra data for callback */
4035     NameContext *pNC;                         /* Naming context */
4036     int n;                                    /* A counter */
4037     int iCur;                                 /* A cursor number */
4038     SrcList *pSrcList;                        /* FROM clause */
4039     struct CCurHint *pCCurHint;               /* Used by codeCursorHint() */
4040     struct RefSrcList *pRefSrcList;           /* sqlite3ReferencesSrcList() */
4041     int *aiCol;                               /* array of column indexes */
4042     struct IdxCover *pIdxCover;               /* Check for index coverage */
4043     struct IdxExprTrans *pIdxTrans;           /* Convert idxed expr to column */
4044     ExprList *pGroupBy;                       /* GROUP BY clause */
4045     Select *pSelect;                          /* HAVING to WHERE clause ctx */
4046     struct WindowRewrite *pRewrite;           /* Window rewrite context */
4047     struct WhereConst *pConst;                /* WHERE clause constants */
4048     struct RenameCtx *pRename;                /* RENAME COLUMN context */
4049     struct Table *pTab;                       /* Table of generated column */
4050     SrcItem *pSrcItem;                        /* A single FROM clause item */
4051     DbFixer *pFix;
4052   } u;
4053 };
4054 
4055 /*
4056 ** The following structure contains information used by the sqliteFix...
4057 ** routines as they walk the parse tree to make database references
4058 ** explicit.
4059 */
4060 struct DbFixer {
4061   Parse *pParse;      /* The parsing context.  Error messages written here */
4062   Walker w;           /* Walker object */
4063   Schema *pSchema;    /* Fix items to this schema */
4064   u8 bTemp;           /* True for TEMP schema entries */
4065   const char *zDb;    /* Make sure all objects are contained in this database */
4066   const char *zType;  /* Type of the container - used for error messages */
4067   const Token *pName; /* Name of the container - used for error messages */
4068 };
4069 
4070 /* Forward declarations */
4071 int sqlite3WalkExpr(Walker*, Expr*);
4072 int sqlite3WalkExprList(Walker*, ExprList*);
4073 int sqlite3WalkSelect(Walker*, Select*);
4074 int sqlite3WalkSelectExpr(Walker*, Select*);
4075 int sqlite3WalkSelectFrom(Walker*, Select*);
4076 int sqlite3ExprWalkNoop(Walker*, Expr*);
4077 int sqlite3SelectWalkNoop(Walker*, Select*);
4078 int sqlite3SelectWalkFail(Walker*, Select*);
4079 int sqlite3WalkerDepthIncrease(Walker*,Select*);
4080 void sqlite3WalkerDepthDecrease(Walker*,Select*);
4081 void sqlite3WalkWinDefnDummyCallback(Walker*,Select*);
4082 
4083 #ifdef SQLITE_DEBUG
4084 void sqlite3SelectWalkAssert2(Walker*, Select*);
4085 #endif
4086 
4087 #ifndef SQLITE_OMIT_CTE
4088 void sqlite3SelectPopWith(Walker*, Select*);
4089 #else
4090 # define sqlite3SelectPopWith 0
4091 #endif
4092 
4093 /*
4094 ** Return code from the parse-tree walking primitives and their
4095 ** callbacks.
4096 */
4097 #define WRC_Continue    0   /* Continue down into children */
4098 #define WRC_Prune       1   /* Omit children but continue walking siblings */
4099 #define WRC_Abort       2   /* Abandon the tree walk */
4100 
4101 /*
4102 ** A single common table expression
4103 */
4104 struct Cte {
4105   char *zName;            /* Name of this CTE */
4106   ExprList *pCols;        /* List of explicit column names, or NULL */
4107   Select *pSelect;        /* The definition of this CTE */
4108   const char *zCteErr;    /* Error message for circular references */
4109   CteUse *pUse;           /* Usage information for this CTE */
4110   u8 eM10d;               /* The MATERIALIZED flag */
4111 };
4112 
4113 /*
4114 ** Allowed values for the materialized flag (eM10d):
4115 */
4116 #define M10d_Yes       0  /* AS MATERIALIZED */
4117 #define M10d_Any       1  /* Not specified.  Query planner's choice */
4118 #define M10d_No        2  /* AS NOT MATERIALIZED */
4119 
4120 /*
4121 ** An instance of the With object represents a WITH clause containing
4122 ** one or more CTEs (common table expressions).
4123 */
4124 struct With {
4125   int nCte;               /* Number of CTEs in the WITH clause */
4126   int bView;              /* Belongs to the outermost Select of a view */
4127   With *pOuter;           /* Containing WITH clause, or NULL */
4128   Cte a[1];               /* For each CTE in the WITH clause.... */
4129 };
4130 
4131 /*
4132 ** The Cte object is not guaranteed to persist for the entire duration
4133 ** of code generation.  (The query flattener or other parser tree
4134 ** edits might delete it.)  The following object records information
4135 ** about each Common Table Expression that must be preserved for the
4136 ** duration of the parse.
4137 **
4138 ** The CteUse objects are freed using sqlite3ParserAddCleanup() rather
4139 ** than sqlite3SelectDelete(), which is what enables them to persist
4140 ** until the end of code generation.
4141 */
4142 struct CteUse {
4143   int nUse;              /* Number of users of this CTE */
4144   int addrM9e;           /* Start of subroutine to compute materialization */
4145   int regRtn;            /* Return address register for addrM9e subroutine */
4146   int iCur;              /* Ephemeral table holding the materialization */
4147   LogEst nRowEst;        /* Estimated number of rows in the table */
4148   u8 eM10d;              /* The MATERIALIZED flag */
4149 };
4150 
4151 
4152 #ifdef SQLITE_DEBUG
4153 /*
4154 ** An instance of the TreeView object is used for printing the content of
4155 ** data structures on sqlite3DebugPrintf() using a tree-like view.
4156 */
4157 struct TreeView {
4158   int iLevel;             /* Which level of the tree we are on */
4159   u8  bLine[100];         /* Draw vertical in column i if bLine[i] is true */
4160 };
4161 #endif /* SQLITE_DEBUG */
4162 
4163 /*
4164 ** This object is used in various ways, most (but not all) related to window
4165 ** functions.
4166 **
4167 **   (1) A single instance of this structure is attached to the
4168 **       the Expr.y.pWin field for each window function in an expression tree.
4169 **       This object holds the information contained in the OVER clause,
4170 **       plus additional fields used during code generation.
4171 **
4172 **   (2) All window functions in a single SELECT form a linked-list
4173 **       attached to Select.pWin.  The Window.pFunc and Window.pExpr
4174 **       fields point back to the expression that is the window function.
4175 **
4176 **   (3) The terms of the WINDOW clause of a SELECT are instances of this
4177 **       object on a linked list attached to Select.pWinDefn.
4178 **
4179 **   (4) For an aggregate function with a FILTER clause, an instance
4180 **       of this object is stored in Expr.y.pWin with eFrmType set to
4181 **       TK_FILTER. In this case the only field used is Window.pFilter.
4182 **
4183 ** The uses (1) and (2) are really the same Window object that just happens
4184 ** to be accessible in two different ways.  Use case (3) are separate objects.
4185 */
4186 struct Window {
4187   char *zName;            /* Name of window (may be NULL) */
4188   char *zBase;            /* Name of base window for chaining (may be NULL) */
4189   ExprList *pPartition;   /* PARTITION BY clause */
4190   ExprList *pOrderBy;     /* ORDER BY clause */
4191   u8 eFrmType;            /* TK_RANGE, TK_GROUPS, TK_ROWS, or 0 */
4192   u8 eStart;              /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
4193   u8 eEnd;                /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
4194   u8 bImplicitFrame;      /* True if frame was implicitly specified */
4195   u8 eExclude;            /* TK_NO, TK_CURRENT, TK_TIES, TK_GROUP, or 0 */
4196   Expr *pStart;           /* Expression for "<expr> PRECEDING" */
4197   Expr *pEnd;             /* Expression for "<expr> FOLLOWING" */
4198   Window **ppThis;        /* Pointer to this object in Select.pWin list */
4199   Window *pNextWin;       /* Next window function belonging to this SELECT */
4200   Expr *pFilter;          /* The FILTER expression */
4201   FuncDef *pWFunc;        /* The function */
4202   int iEphCsr;            /* Partition buffer or Peer buffer */
4203   int regAccum;           /* Accumulator */
4204   int regResult;          /* Interim result */
4205   int csrApp;             /* Function cursor (used by min/max) */
4206   int regApp;             /* Function register (also used by min/max) */
4207   int regPart;            /* Array of registers for PARTITION BY values */
4208   Expr *pOwner;           /* Expression object this window is attached to */
4209   int nBufferCol;         /* Number of columns in buffer table */
4210   int iArgCol;            /* Offset of first argument for this function */
4211   int regOne;             /* Register containing constant value 1 */
4212   int regStartRowid;
4213   int regEndRowid;
4214   u8 bExprArgs;           /* Defer evaluation of window function arguments
4215                           ** due to the SQLITE_SUBTYPE flag */
4216 };
4217 
4218 #ifndef SQLITE_OMIT_WINDOWFUNC
4219 void sqlite3WindowDelete(sqlite3*, Window*);
4220 void sqlite3WindowUnlinkFromSelect(Window*);
4221 void sqlite3WindowListDelete(sqlite3 *db, Window *p);
4222 Window *sqlite3WindowAlloc(Parse*, int, int, Expr*, int , Expr*, u8);
4223 void sqlite3WindowAttach(Parse*, Expr*, Window*);
4224 void sqlite3WindowLink(Select *pSel, Window *pWin);
4225 int sqlite3WindowCompare(const Parse*, const Window*, const Window*, int);
4226 void sqlite3WindowCodeInit(Parse*, Select*);
4227 void sqlite3WindowCodeStep(Parse*, Select*, WhereInfo*, int, int);
4228 int sqlite3WindowRewrite(Parse*, Select*);
4229 void sqlite3WindowUpdate(Parse*, Window*, Window*, FuncDef*);
4230 Window *sqlite3WindowDup(sqlite3 *db, Expr *pOwner, Window *p);
4231 Window *sqlite3WindowListDup(sqlite3 *db, Window *p);
4232 void sqlite3WindowFunctions(void);
4233 void sqlite3WindowChain(Parse*, Window*, Window*);
4234 Window *sqlite3WindowAssemble(Parse*, Window*, ExprList*, ExprList*, Token*);
4235 #else
4236 # define sqlite3WindowDelete(a,b)
4237 # define sqlite3WindowFunctions()
4238 # define sqlite3WindowAttach(a,b,c)
4239 #endif
4240 
4241 /*
4242 ** Assuming zIn points to the first byte of a UTF-8 character,
4243 ** advance zIn to point to the first byte of the next UTF-8 character.
4244 */
4245 #define SQLITE_SKIP_UTF8(zIn) {                        \
4246   if( (*(zIn++))>=0xc0 ){                              \
4247     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
4248   }                                                    \
4249 }
4250 
4251 /*
4252 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
4253 ** the same name but without the _BKPT suffix.  These macros invoke
4254 ** routines that report the line-number on which the error originated
4255 ** using sqlite3_log().  The routines also provide a convenient place
4256 ** to set a debugger breakpoint.
4257 */
4258 int sqlite3ReportError(int iErr, int lineno, const char *zType);
4259 int sqlite3CorruptError(int);
4260 int sqlite3MisuseError(int);
4261 int sqlite3CantopenError(int);
4262 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
4263 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
4264 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
4265 #ifdef SQLITE_DEBUG
4266   int sqlite3NomemError(int);
4267   int sqlite3IoerrnomemError(int);
4268 # define SQLITE_NOMEM_BKPT sqlite3NomemError(__LINE__)
4269 # define SQLITE_IOERR_NOMEM_BKPT sqlite3IoerrnomemError(__LINE__)
4270 #else
4271 # define SQLITE_NOMEM_BKPT SQLITE_NOMEM
4272 # define SQLITE_IOERR_NOMEM_BKPT SQLITE_IOERR_NOMEM
4273 #endif
4274 #if defined(SQLITE_DEBUG) || defined(SQLITE_ENABLE_CORRUPT_PGNO)
4275   int sqlite3CorruptPgnoError(int,Pgno);
4276 # define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptPgnoError(__LINE__,(P))
4277 #else
4278 # define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptError(__LINE__)
4279 #endif
4280 
4281 /*
4282 ** FTS3 and FTS4 both require virtual table support
4283 */
4284 #if defined(SQLITE_OMIT_VIRTUALTABLE)
4285 # undef SQLITE_ENABLE_FTS3
4286 # undef SQLITE_ENABLE_FTS4
4287 #endif
4288 
4289 /*
4290 ** FTS4 is really an extension for FTS3.  It is enabled using the
4291 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also call
4292 ** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
4293 */
4294 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
4295 # define SQLITE_ENABLE_FTS3 1
4296 #endif
4297 
4298 /*
4299 ** The ctype.h header is needed for non-ASCII systems.  It is also
4300 ** needed by FTS3 when FTS3 is included in the amalgamation.
4301 */
4302 #if !defined(SQLITE_ASCII) || \
4303     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
4304 # include <ctype.h>
4305 #endif
4306 
4307 /*
4308 ** The following macros mimic the standard library functions toupper(),
4309 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
4310 ** sqlite versions only work for ASCII characters, regardless of locale.
4311 */
4312 #ifdef SQLITE_ASCII
4313 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
4314 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
4315 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
4316 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
4317 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
4318 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
4319 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
4320 # define sqlite3Isquote(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x80)
4321 #else
4322 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
4323 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
4324 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
4325 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
4326 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
4327 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
4328 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
4329 # define sqlite3Isquote(x)   ((x)=='"'||(x)=='\''||(x)=='['||(x)=='`')
4330 #endif
4331 int sqlite3IsIdChar(u8);
4332 
4333 /*
4334 ** Internal function prototypes
4335 */
4336 int sqlite3StrICmp(const char*,const char*);
4337 int sqlite3Strlen30(const char*);
4338 #define sqlite3Strlen30NN(C) (strlen(C)&0x3fffffff)
4339 char *sqlite3ColumnType(Column*,char*);
4340 #define sqlite3StrNICmp sqlite3_strnicmp
4341 
4342 int sqlite3MallocInit(void);
4343 void sqlite3MallocEnd(void);
4344 void *sqlite3Malloc(u64);
4345 void *sqlite3MallocZero(u64);
4346 void *sqlite3DbMallocZero(sqlite3*, u64);
4347 void *sqlite3DbMallocRaw(sqlite3*, u64);
4348 void *sqlite3DbMallocRawNN(sqlite3*, u64);
4349 char *sqlite3DbStrDup(sqlite3*,const char*);
4350 char *sqlite3DbStrNDup(sqlite3*,const char*, u64);
4351 char *sqlite3DbSpanDup(sqlite3*,const char*,const char*);
4352 void *sqlite3Realloc(void*, u64);
4353 void *sqlite3DbReallocOrFree(sqlite3 *, void *, u64);
4354 void *sqlite3DbRealloc(sqlite3 *, void *, u64);
4355 void sqlite3DbFree(sqlite3*, void*);
4356 void sqlite3DbFreeNN(sqlite3*, void*);
4357 int sqlite3MallocSize(const void*);
4358 int sqlite3DbMallocSize(sqlite3*, const void*);
4359 void *sqlite3PageMalloc(int);
4360 void sqlite3PageFree(void*);
4361 void sqlite3MemSetDefault(void);
4362 #ifndef SQLITE_UNTESTABLE
4363 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
4364 #endif
4365 int sqlite3HeapNearlyFull(void);
4366 
4367 /*
4368 ** On systems with ample stack space and that support alloca(), make
4369 ** use of alloca() to obtain space for large automatic objects.  By default,
4370 ** obtain space from malloc().
4371 **
4372 ** The alloca() routine never returns NULL.  This will cause code paths
4373 ** that deal with sqlite3StackAlloc() failures to be unreachable.
4374 */
4375 #ifdef SQLITE_USE_ALLOCA
4376 # define sqlite3StackAllocRaw(D,N)   alloca(N)
4377 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
4378 # define sqlite3StackFree(D,P)
4379 #else
4380 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
4381 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
4382 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
4383 #endif
4384 
4385 /* Do not allow both MEMSYS5 and MEMSYS3 to be defined together.  If they
4386 ** are, disable MEMSYS3
4387 */
4388 #ifdef SQLITE_ENABLE_MEMSYS5
4389 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
4390 #undef SQLITE_ENABLE_MEMSYS3
4391 #endif
4392 #ifdef SQLITE_ENABLE_MEMSYS3
4393 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
4394 #endif
4395 
4396 
4397 #ifndef SQLITE_MUTEX_OMIT
4398   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
4399   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
4400   sqlite3_mutex *sqlite3MutexAlloc(int);
4401   int sqlite3MutexInit(void);
4402   int sqlite3MutexEnd(void);
4403 #endif
4404 #if !defined(SQLITE_MUTEX_OMIT) && !defined(SQLITE_MUTEX_NOOP)
4405   void sqlite3MemoryBarrier(void);
4406 #else
4407 # define sqlite3MemoryBarrier()
4408 #endif
4409 
4410 sqlite3_int64 sqlite3StatusValue(int);
4411 void sqlite3StatusUp(int, int);
4412 void sqlite3StatusDown(int, int);
4413 void sqlite3StatusHighwater(int, int);
4414 int sqlite3LookasideUsed(sqlite3*,int*);
4415 
4416 /* Access to mutexes used by sqlite3_status() */
4417 sqlite3_mutex *sqlite3Pcache1Mutex(void);
4418 sqlite3_mutex *sqlite3MallocMutex(void);
4419 
4420 #if defined(SQLITE_ENABLE_MULTITHREADED_CHECKS) && !defined(SQLITE_MUTEX_OMIT)
4421 void sqlite3MutexWarnOnContention(sqlite3_mutex*);
4422 #else
4423 # define sqlite3MutexWarnOnContention(x)
4424 #endif
4425 
4426 #ifndef SQLITE_OMIT_FLOATING_POINT
4427 # define EXP754 (((u64)0x7ff)<<52)
4428 # define MAN754 ((((u64)1)<<52)-1)
4429 # define IsNaN(X) (((X)&EXP754)==EXP754 && ((X)&MAN754)!=0)
4430   int sqlite3IsNaN(double);
4431 #else
4432 # define IsNaN(X)         0
4433 # define sqlite3IsNaN(X)  0
4434 #endif
4435 
4436 /*
4437 ** An instance of the following structure holds information about SQL
4438 ** functions arguments that are the parameters to the printf() function.
4439 */
4440 struct PrintfArguments {
4441   int nArg;                /* Total number of arguments */
4442   int nUsed;               /* Number of arguments used so far */
4443   sqlite3_value **apArg;   /* The argument values */
4444 };
4445 
4446 char *sqlite3MPrintf(sqlite3*,const char*, ...);
4447 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
4448 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
4449   void sqlite3DebugPrintf(const char*, ...);
4450 #endif
4451 #if defined(SQLITE_TEST)
4452   void *sqlite3TestTextToPtr(const char*);
4453 #endif
4454 
4455 #if defined(SQLITE_DEBUG)
4456   void sqlite3TreeViewLine(TreeView*, const char *zFormat, ...);
4457   void sqlite3TreeViewExpr(TreeView*, const Expr*, u8);
4458   void sqlite3TreeViewBareExprList(TreeView*, const ExprList*, const char*);
4459   void sqlite3TreeViewExprList(TreeView*, const ExprList*, u8, const char*);
4460   void sqlite3TreeViewBareIdList(TreeView*, const IdList*, const char*);
4461   void sqlite3TreeViewIdList(TreeView*, const IdList*, u8, const char*);
4462   void sqlite3TreeViewSrcList(TreeView*, const SrcList*);
4463   void sqlite3TreeViewSelect(TreeView*, const Select*, u8);
4464   void sqlite3TreeViewWith(TreeView*, const With*, u8);
4465   void sqlite3TreeViewUpsert(TreeView*, const Upsert*, u8);
4466   void sqlite3TreeViewDelete(const With*, const SrcList*, const Expr*,
4467                              const ExprList*,const Expr*, const Trigger*);
4468   void sqlite3TreeViewInsert(const With*, const SrcList*,
4469                              const IdList*, const Select*, const ExprList*,
4470                              int, const Upsert*, const Trigger*);
4471   void sqlite3TreeViewUpdate(const With*, const SrcList*, const ExprList*,
4472                              const Expr*, int, const ExprList*, const Expr*,
4473                              const Upsert*, const Trigger*);
4474 #ifndef SQLITE_OMIT_TRIGGER
4475   void sqlite3TreeViewTriggerStep(TreeView*, const TriggerStep*, u8, u8);
4476   void sqlite3TreeViewTrigger(TreeView*, const Trigger*, u8, u8);
4477 #endif
4478 #ifndef SQLITE_OMIT_WINDOWFUNC
4479   void sqlite3TreeViewWindow(TreeView*, const Window*, u8);
4480   void sqlite3TreeViewWinFunc(TreeView*, const Window*, u8);
4481 #endif
4482   void sqlite3ShowExpr(const Expr*);
4483   void sqlite3ShowExprList(const ExprList*);
4484   void sqlite3ShowIdList(const IdList*);
4485   void sqlite3ShowSrcList(const SrcList*);
4486   void sqlite3ShowSelect(const Select*);
4487   void sqlite3ShowWith(const With*);
4488   void sqlite3ShowUpsert(const Upsert*);
4489 #ifndef SQLITE_OMIT_TRIGGER
4490   void sqlite3ShowTriggerStep(const TriggerStep*);
4491   void sqlite3ShowTriggerStepList(const TriggerStep*);
4492   void sqlite3ShowTrigger(const Trigger*);
4493   void sqlite3ShowTriggerList(const Trigger*);
4494 #endif
4495 #ifndef SQLITE_OMIT_WINDOWFUNC
4496   void sqlite3ShowWindow(const Window*);
4497   void sqlite3ShowWinFunc(const Window*);
4498 #endif
4499 #endif
4500 
4501 void sqlite3SetString(char **, sqlite3*, const char*);
4502 void sqlite3ErrorMsg(Parse*, const char*, ...);
4503 int sqlite3ErrorToParser(sqlite3*,int);
4504 void sqlite3Dequote(char*);
4505 void sqlite3DequoteExpr(Expr*);
4506 void sqlite3DequoteToken(Token*);
4507 void sqlite3TokenInit(Token*,char*);
4508 int sqlite3KeywordCode(const unsigned char*, int);
4509 int sqlite3RunParser(Parse*, const char*);
4510 void sqlite3FinishCoding(Parse*);
4511 int sqlite3GetTempReg(Parse*);
4512 void sqlite3ReleaseTempReg(Parse*,int);
4513 int sqlite3GetTempRange(Parse*,int);
4514 void sqlite3ReleaseTempRange(Parse*,int,int);
4515 void sqlite3ClearTempRegCache(Parse*);
4516 #ifdef SQLITE_DEBUG
4517 int sqlite3NoTempsInRange(Parse*,int,int);
4518 #endif
4519 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
4520 Expr *sqlite3Expr(sqlite3*,int,const char*);
4521 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
4522 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*);
4523 void sqlite3PExprAddSelect(Parse*, Expr*, Select*);
4524 Expr *sqlite3ExprAnd(Parse*,Expr*, Expr*);
4525 Expr *sqlite3ExprSimplifiedAndOr(Expr*);
4526 Expr *sqlite3ExprFunction(Parse*,ExprList*, const Token*, int);
4527 void sqlite3ExprFunctionUsable(Parse*,const Expr*,const FuncDef*);
4528 void sqlite3ExprAssignVarNumber(Parse*, Expr*, u32);
4529 void sqlite3ExprDelete(sqlite3*, Expr*);
4530 void sqlite3ExprDeferredDelete(Parse*, Expr*);
4531 void sqlite3ExprUnmapAndDelete(Parse*, Expr*);
4532 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
4533 ExprList *sqlite3ExprListAppendVector(Parse*,ExprList*,IdList*,Expr*);
4534 Select *sqlite3ExprListToValues(Parse*, int, ExprList*);
4535 void sqlite3ExprListSetSortOrder(ExprList*,int,int);
4536 void sqlite3ExprListSetName(Parse*,ExprList*,const Token*,int);
4537 void sqlite3ExprListSetSpan(Parse*,ExprList*,const char*,const char*);
4538 void sqlite3ExprListDelete(sqlite3*, ExprList*);
4539 u32 sqlite3ExprListFlags(const ExprList*);
4540 int sqlite3IndexHasDuplicateRootPage(Index*);
4541 int sqlite3Init(sqlite3*, char**);
4542 int sqlite3InitCallback(void*, int, char**, char**);
4543 int sqlite3InitOne(sqlite3*, int, char**, u32);
4544 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
4545 #ifndef SQLITE_OMIT_VIRTUALTABLE
4546 Module *sqlite3PragmaVtabRegister(sqlite3*,const char *zName);
4547 #endif
4548 void sqlite3ResetAllSchemasOfConnection(sqlite3*);
4549 void sqlite3ResetOneSchema(sqlite3*,int);
4550 void sqlite3CollapseDatabaseArray(sqlite3*);
4551 void sqlite3CommitInternalChanges(sqlite3*);
4552 void sqlite3ColumnSetExpr(Parse*,Table*,Column*,Expr*);
4553 Expr *sqlite3ColumnExpr(Table*,Column*);
4554 void sqlite3ColumnSetColl(sqlite3*,Column*,const char*zColl);
4555 const char *sqlite3ColumnColl(Column*);
4556 void sqlite3DeleteColumnNames(sqlite3*,Table*);
4557 void sqlite3GenerateColumnNames(Parse *pParse, Select *pSelect);
4558 int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
4559 void sqlite3SelectAddColumnTypeAndCollation(Parse*,Table*,Select*,char);
4560 Table *sqlite3ResultSetOfSelect(Parse*,Select*,char);
4561 void sqlite3OpenSchemaTable(Parse *, int);
4562 Index *sqlite3PrimaryKeyIndex(Table*);
4563 i16 sqlite3TableColumnToIndex(Index*, i16);
4564 #ifdef SQLITE_OMIT_GENERATED_COLUMNS
4565 # define sqlite3TableColumnToStorage(T,X) (X)  /* No-op pass-through */
4566 # define sqlite3StorageColumnToTable(T,X) (X)  /* No-op pass-through */
4567 #else
4568   i16 sqlite3TableColumnToStorage(Table*, i16);
4569   i16 sqlite3StorageColumnToTable(Table*, i16);
4570 #endif
4571 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
4572 #if SQLITE_ENABLE_HIDDEN_COLUMNS
4573   void sqlite3ColumnPropertiesFromName(Table*, Column*);
4574 #else
4575 # define sqlite3ColumnPropertiesFromName(T,C) /* no-op */
4576 #endif
4577 void sqlite3AddColumn(Parse*,Token,Token);
4578 void sqlite3AddNotNull(Parse*, int);
4579 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
4580 void sqlite3AddCheckConstraint(Parse*, Expr*, const char*, const char*);
4581 void sqlite3AddDefaultValue(Parse*,Expr*,const char*,const char*);
4582 void sqlite3AddCollateType(Parse*, Token*);
4583 void sqlite3AddGenerated(Parse*,Expr*,Token*);
4584 void sqlite3EndTable(Parse*,Token*,Token*,u32,Select*);
4585 void sqlite3AddReturning(Parse*,ExprList*);
4586 int sqlite3ParseUri(const char*,const char*,unsigned int*,
4587                     sqlite3_vfs**,char**,char **);
4588 #define sqlite3CodecQueryParameters(A,B,C) 0
4589 Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
4590 
4591 #ifdef SQLITE_UNTESTABLE
4592 # define sqlite3FaultSim(X) SQLITE_OK
4593 #else
4594   int sqlite3FaultSim(int);
4595 #endif
4596 
4597 Bitvec *sqlite3BitvecCreate(u32);
4598 int sqlite3BitvecTest(Bitvec*, u32);
4599 int sqlite3BitvecTestNotNull(Bitvec*, u32);
4600 int sqlite3BitvecSet(Bitvec*, u32);
4601 void sqlite3BitvecClear(Bitvec*, u32, void*);
4602 void sqlite3BitvecDestroy(Bitvec*);
4603 u32 sqlite3BitvecSize(Bitvec*);
4604 #ifndef SQLITE_UNTESTABLE
4605 int sqlite3BitvecBuiltinTest(int,int*);
4606 #endif
4607 
4608 RowSet *sqlite3RowSetInit(sqlite3*);
4609 void sqlite3RowSetDelete(void*);
4610 void sqlite3RowSetClear(void*);
4611 void sqlite3RowSetInsert(RowSet*, i64);
4612 int sqlite3RowSetTest(RowSet*, int iBatch, i64);
4613 int sqlite3RowSetNext(RowSet*, i64*);
4614 
4615 void sqlite3CreateView(Parse*,Token*,Token*,Token*,ExprList*,Select*,int,int);
4616 
4617 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
4618   int sqlite3ViewGetColumnNames(Parse*,Table*);
4619 #else
4620 # define sqlite3ViewGetColumnNames(A,B) 0
4621 #endif
4622 
4623 #if SQLITE_MAX_ATTACHED>30
4624   int sqlite3DbMaskAllZero(yDbMask);
4625 #endif
4626 void sqlite3DropTable(Parse*, SrcList*, int, int);
4627 void sqlite3CodeDropTable(Parse*, Table*, int, int);
4628 void sqlite3DeleteTable(sqlite3*, Table*);
4629 void sqlite3FreeIndex(sqlite3*, Index*);
4630 #ifndef SQLITE_OMIT_AUTOINCREMENT
4631   void sqlite3AutoincrementBegin(Parse *pParse);
4632   void sqlite3AutoincrementEnd(Parse *pParse);
4633 #else
4634 # define sqlite3AutoincrementBegin(X)
4635 # define sqlite3AutoincrementEnd(X)
4636 #endif
4637 void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int, Upsert*);
4638 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
4639   void sqlite3ComputeGeneratedColumns(Parse*, int, Table*);
4640 #endif
4641 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
4642 IdList *sqlite3IdListAppend(Parse*, IdList*, Token*);
4643 int sqlite3IdListIndex(IdList*,const char*);
4644 SrcList *sqlite3SrcListEnlarge(Parse*, SrcList*, int, int);
4645 SrcList *sqlite3SrcListAppendList(Parse *pParse, SrcList *p1, SrcList *p2);
4646 SrcList *sqlite3SrcListAppend(Parse*, SrcList*, Token*, Token*);
4647 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
4648                                       Token*, Select*, OnOrUsing*);
4649 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
4650 void sqlite3SrcListFuncArgs(Parse*, SrcList*, ExprList*);
4651 int sqlite3IndexedByLookup(Parse *, SrcItem *);
4652 void sqlite3SrcListShiftJoinType(Parse*,SrcList*);
4653 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
4654 void sqlite3IdListDelete(sqlite3*, IdList*);
4655 void sqlite3ClearOnOrUsing(sqlite3*, OnOrUsing*);
4656 void sqlite3SrcListDelete(sqlite3*, SrcList*);
4657 Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
4658 void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
4659                           Expr*, int, int, u8);
4660 void sqlite3DropIndex(Parse*, SrcList*, int);
4661 int sqlite3Select(Parse*, Select*, SelectDest*);
4662 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
4663                          Expr*,ExprList*,u32,Expr*);
4664 void sqlite3SelectDelete(sqlite3*, Select*);
4665 Table *sqlite3SrcListLookup(Parse*, SrcList*);
4666 int sqlite3IsReadOnly(Parse*, Table*, int);
4667 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
4668 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
4669 Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,char*);
4670 #endif
4671 void sqlite3CodeChangeCount(Vdbe*,int,const char*);
4672 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*, ExprList*, Expr*);
4673 void sqlite3Update(Parse*, SrcList*, ExprList*,Expr*,int,ExprList*,Expr*,
4674                    Upsert*);
4675 WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,
4676                              ExprList*,Select*,u16,int);
4677 void sqlite3WhereEnd(WhereInfo*);
4678 LogEst sqlite3WhereOutputRowCount(WhereInfo*);
4679 int sqlite3WhereIsDistinct(WhereInfo*);
4680 int sqlite3WhereIsOrdered(WhereInfo*);
4681 int sqlite3WhereOrderByLimitOptLabel(WhereInfo*);
4682 void sqlite3WhereMinMaxOptEarlyOut(Vdbe*,WhereInfo*);
4683 int sqlite3WhereIsSorted(WhereInfo*);
4684 int sqlite3WhereContinueLabel(WhereInfo*);
4685 int sqlite3WhereBreakLabel(WhereInfo*);
4686 int sqlite3WhereOkOnePass(WhereInfo*, int*);
4687 #define ONEPASS_OFF      0        /* Use of ONEPASS not allowed */
4688 #define ONEPASS_SINGLE   1        /* ONEPASS valid for a single row update */
4689 #define ONEPASS_MULTI    2        /* ONEPASS is valid for multiple rows */
4690 int sqlite3WhereUsesDeferredSeek(WhereInfo*);
4691 void sqlite3ExprCodeLoadIndexColumn(Parse*, Index*, int, int, int);
4692 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
4693 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
4694 void sqlite3ExprCodeMove(Parse*, int, int, int);
4695 void sqlite3ExprCode(Parse*, Expr*, int);
4696 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
4697 void sqlite3ExprCodeGeneratedColumn(Parse*, Table*, Column*, int);
4698 #endif
4699 void sqlite3ExprCodeCopy(Parse*, Expr*, int);
4700 void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
4701 int sqlite3ExprCodeRunJustOnce(Parse*, Expr*, int);
4702 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
4703 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
4704 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int, u8);
4705 #define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
4706 #define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
4707 #define SQLITE_ECEL_REF      0x04  /* Use ExprList.u.x.iOrderByCol */
4708 #define SQLITE_ECEL_OMITREF  0x08  /* Omit if ExprList.u.x.iOrderByCol */
4709 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
4710 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
4711 void sqlite3ExprIfFalseDup(Parse*, Expr*, int, int);
4712 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
4713 #define LOCATE_VIEW    0x01
4714 #define LOCATE_NOERR   0x02
4715 Table *sqlite3LocateTable(Parse*,u32 flags,const char*, const char*);
4716 const char *sqlite3PreferredTableName(const char*);
4717 Table *sqlite3LocateTableItem(Parse*,u32 flags,SrcItem *);
4718 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
4719 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
4720 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
4721 void sqlite3Vacuum(Parse*,Token*,Expr*);
4722 int sqlite3RunVacuum(char**, sqlite3*, int, sqlite3_value*);
4723 char *sqlite3NameFromToken(sqlite3*, const Token*);
4724 int sqlite3ExprCompare(const Parse*,const Expr*,const Expr*, int);
4725 int sqlite3ExprCompareSkip(Expr*,Expr*,int);
4726 int sqlite3ExprListCompare(const ExprList*,const ExprList*, int);
4727 int sqlite3ExprImpliesExpr(const Parse*,const Expr*,const Expr*, int);
4728 int sqlite3ExprImpliesNonNullRow(Expr*,int);
4729 void sqlite3AggInfoPersistWalkerInit(Walker*,Parse*);
4730 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
4731 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
4732 int sqlite3ExprCoveredByIndex(Expr*, int iCur, Index *pIdx);
4733 int sqlite3ReferencesSrcList(Parse*, Expr*, SrcList*);
4734 Vdbe *sqlite3GetVdbe(Parse*);
4735 #ifndef SQLITE_UNTESTABLE
4736 void sqlite3PrngSaveState(void);
4737 void sqlite3PrngRestoreState(void);
4738 #endif
4739 void sqlite3RollbackAll(sqlite3*,int);
4740 void sqlite3CodeVerifySchema(Parse*, int);
4741 void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
4742 void sqlite3BeginTransaction(Parse*, int);
4743 void sqlite3EndTransaction(Parse*,int);
4744 void sqlite3Savepoint(Parse*, int, Token*);
4745 void sqlite3CloseSavepoints(sqlite3 *);
4746 void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
4747 u32 sqlite3IsTrueOrFalse(const char*);
4748 int sqlite3ExprIdToTrueFalse(Expr*);
4749 int sqlite3ExprTruthValue(const Expr*);
4750 int sqlite3ExprIsConstant(Expr*);
4751 int sqlite3ExprIsConstantNotJoin(Expr*);
4752 int sqlite3ExprIsConstantOrFunction(Expr*, u8);
4753 int sqlite3ExprIsConstantOrGroupBy(Parse*, Expr*, ExprList*);
4754 int sqlite3ExprIsTableConstant(Expr*,int);
4755 int sqlite3ExprIsTableConstraint(Expr*,const SrcItem*);
4756 #ifdef SQLITE_ENABLE_CURSOR_HINTS
4757 int sqlite3ExprContainsSubquery(Expr*);
4758 #endif
4759 int sqlite3ExprIsInteger(const Expr*, int*);
4760 int sqlite3ExprCanBeNull(const Expr*);
4761 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
4762 int sqlite3IsRowid(const char*);
4763 void sqlite3GenerateRowDelete(
4764     Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8,int);
4765 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*, int);
4766 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
4767 void sqlite3ResolvePartIdxLabel(Parse*,int);
4768 int sqlite3ExprReferencesUpdatedColumn(Expr*,int*,int);
4769 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
4770                                      u8,u8,int,int*,int*,Upsert*);
4771 #ifdef SQLITE_ENABLE_NULL_TRIM
4772   void sqlite3SetMakeRecordP5(Vdbe*,Table*);
4773 #else
4774 # define sqlite3SetMakeRecordP5(A,B)
4775 #endif
4776 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
4777 int sqlite3OpenTableAndIndices(Parse*, Table*, int, u8, int, u8*, int*, int*);
4778 void sqlite3BeginWriteOperation(Parse*, int, int);
4779 void sqlite3MultiWrite(Parse*);
4780 void sqlite3MayAbort(Parse*);
4781 void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
4782 void sqlite3UniqueConstraint(Parse*, int, Index*);
4783 void sqlite3RowidConstraint(Parse*, int, Table*);
4784 Expr *sqlite3ExprDup(sqlite3*,const Expr*,int);
4785 ExprList *sqlite3ExprListDup(sqlite3*,const ExprList*,int);
4786 SrcList *sqlite3SrcListDup(sqlite3*,const SrcList*,int);
4787 IdList *sqlite3IdListDup(sqlite3*,const IdList*);
4788 Select *sqlite3SelectDup(sqlite3*,const Select*,int);
4789 FuncDef *sqlite3FunctionSearch(int,const char*);
4790 void sqlite3InsertBuiltinFuncs(FuncDef*,int);
4791 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,u8,u8);
4792 void sqlite3QuoteValue(StrAccum*,sqlite3_value*);
4793 void sqlite3RegisterBuiltinFunctions(void);
4794 void sqlite3RegisterDateTimeFunctions(void);
4795 void sqlite3RegisterJsonFunctions(void);
4796 void sqlite3RegisterPerConnectionBuiltinFunctions(sqlite3*);
4797 #if !defined(SQLITE_OMIT_VIRTUALTABLE) && !defined(SQLITE_OMIT_JSON)
4798   int sqlite3JsonTableFunctions(sqlite3*);
4799 #endif
4800 int sqlite3SafetyCheckOk(sqlite3*);
4801 int sqlite3SafetyCheckSickOrOk(sqlite3*);
4802 void sqlite3ChangeCookie(Parse*, int);
4803 With *sqlite3WithDup(sqlite3 *db, With *p);
4804 
4805 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
4806 void sqlite3MaterializeView(Parse*, Table*, Expr*, ExprList*,Expr*,int);
4807 #endif
4808 
4809 #ifndef SQLITE_OMIT_TRIGGER
4810   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
4811                            Expr*,int, int);
4812   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
4813   void sqlite3DropTrigger(Parse*, SrcList*, int);
4814   void sqlite3DropTriggerPtr(Parse*, Trigger*);
4815   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
4816   Trigger *sqlite3TriggerList(Parse *, Table *);
4817   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
4818                             int, int, int);
4819   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
4820   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
4821   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
4822   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*,
4823                                         const char*,const char*);
4824   TriggerStep *sqlite3TriggerInsertStep(Parse*,Token*, IdList*,
4825                                         Select*,u8,Upsert*,
4826                                         const char*,const char*);
4827   TriggerStep *sqlite3TriggerUpdateStep(Parse*,Token*,SrcList*,ExprList*,
4828                                         Expr*, u8, const char*,const char*);
4829   TriggerStep *sqlite3TriggerDeleteStep(Parse*,Token*, Expr*,
4830                                         const char*,const char*);
4831   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
4832   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
4833   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
4834   SrcList *sqlite3TriggerStepSrc(Parse*, TriggerStep*);
4835 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
4836 # define sqlite3IsToplevel(p) ((p)->pToplevel==0)
4837 #else
4838 # define sqlite3TriggersExist(B,C,D,E,F) 0
4839 # define sqlite3DeleteTrigger(A,B)
4840 # define sqlite3DropTriggerPtr(A,B)
4841 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
4842 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
4843 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
4844 # define sqlite3TriggerList(X, Y) 0
4845 # define sqlite3ParseToplevel(p) p
4846 # define sqlite3IsToplevel(p) 1
4847 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
4848 # define sqlite3TriggerStepSrc(A,B) 0
4849 #endif
4850 
4851 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
4852 int sqlite3ColumnIndex(Table *pTab, const char *zCol);
4853 void sqlite3SrcItemColumnUsed(SrcItem*,int);
4854 void sqlite3SetJoinExpr(Expr*,int,u32);
4855 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
4856 void sqlite3DeferForeignKey(Parse*, int);
4857 #ifndef SQLITE_OMIT_AUTHORIZATION
4858   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
4859   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
4860   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
4861   void sqlite3AuthContextPop(AuthContext*);
4862   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
4863 #else
4864 # define sqlite3AuthRead(a,b,c,d)
4865 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
4866 # define sqlite3AuthContextPush(a,b,c)
4867 # define sqlite3AuthContextPop(a)  ((void)(a))
4868 #endif
4869 int sqlite3DbIsNamed(sqlite3 *db, int iDb, const char *zName);
4870 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
4871 void sqlite3Detach(Parse*, Expr*);
4872 void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
4873 int sqlite3FixSrcList(DbFixer*, SrcList*);
4874 int sqlite3FixSelect(DbFixer*, Select*);
4875 int sqlite3FixExpr(DbFixer*, Expr*);
4876 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
4877 int sqlite3RealSameAsInt(double,sqlite3_int64);
4878 void sqlite3Int64ToText(i64,char*);
4879 int sqlite3AtoF(const char *z, double*, int, u8);
4880 int sqlite3GetInt32(const char *, int*);
4881 int sqlite3GetUInt32(const char*, u32*);
4882 int sqlite3Atoi(const char*);
4883 #ifndef SQLITE_OMIT_UTF16
4884 int sqlite3Utf16ByteLen(const void *pData, int nChar);
4885 #endif
4886 int sqlite3Utf8CharLen(const char *pData, int nByte);
4887 u32 sqlite3Utf8Read(const u8**);
4888 LogEst sqlite3LogEst(u64);
4889 LogEst sqlite3LogEstAdd(LogEst,LogEst);
4890 LogEst sqlite3LogEstFromDouble(double);
4891 u64 sqlite3LogEstToInt(LogEst);
4892 VList *sqlite3VListAdd(sqlite3*,VList*,const char*,int,int);
4893 const char *sqlite3VListNumToName(VList*,int);
4894 int sqlite3VListNameToNum(VList*,const char*,int);
4895 
4896 /*
4897 ** Routines to read and write variable-length integers.  These used to
4898 ** be defined locally, but now we use the varint routines in the util.c
4899 ** file.
4900 */
4901 int sqlite3PutVarint(unsigned char*, u64);
4902 u8 sqlite3GetVarint(const unsigned char *, u64 *);
4903 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
4904 int sqlite3VarintLen(u64 v);
4905 
4906 /*
4907 ** The common case is for a varint to be a single byte.  They following
4908 ** macros handle the common case without a procedure call, but then call
4909 ** the procedure for larger varints.
4910 */
4911 #define getVarint32(A,B)  \
4912   (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
4913 #define getVarint32NR(A,B) \
4914   B=(u32)*(A);if(B>=0x80)sqlite3GetVarint32((A),(u32*)&(B))
4915 #define putVarint32(A,B)  \
4916   (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
4917   sqlite3PutVarint((A),(B)))
4918 #define getVarint    sqlite3GetVarint
4919 #define putVarint    sqlite3PutVarint
4920 
4921 
4922 const char *sqlite3IndexAffinityStr(sqlite3*, Index*);
4923 void sqlite3TableAffinity(Vdbe*, Table*, int);
4924 char sqlite3CompareAffinity(const Expr *pExpr, char aff2);
4925 int sqlite3IndexAffinityOk(const Expr *pExpr, char idx_affinity);
4926 char sqlite3TableColumnAffinity(const Table*,int);
4927 char sqlite3ExprAffinity(const Expr *pExpr);
4928 int sqlite3Atoi64(const char*, i64*, int, u8);
4929 int sqlite3DecOrHexToI64(const char*, i64*);
4930 void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
4931 void sqlite3Error(sqlite3*,int);
4932 void sqlite3ErrorClear(sqlite3*);
4933 void sqlite3SystemError(sqlite3*,int);
4934 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
4935 u8 sqlite3HexToInt(int h);
4936 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
4937 
4938 #if defined(SQLITE_NEED_ERR_NAME)
4939 const char *sqlite3ErrName(int);
4940 #endif
4941 
4942 #ifndef SQLITE_OMIT_DESERIALIZE
4943 int sqlite3MemdbInit(void);
4944 #endif
4945 
4946 const char *sqlite3ErrStr(int);
4947 int sqlite3ReadSchema(Parse *pParse);
4948 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
4949 int sqlite3IsBinary(const CollSeq*);
4950 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
4951 void sqlite3SetTextEncoding(sqlite3 *db, u8);
4952 CollSeq *sqlite3ExprCollSeq(Parse *pParse, const Expr *pExpr);
4953 CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, const Expr *pExpr);
4954 int sqlite3ExprCollSeqMatch(Parse*,const Expr*,const Expr*);
4955 Expr *sqlite3ExprAddCollateToken(const Parse *pParse, Expr*, const Token*, int);
4956 Expr *sqlite3ExprAddCollateString(const Parse*,Expr*,const char*);
4957 Expr *sqlite3ExprSkipCollate(Expr*);
4958 Expr *sqlite3ExprSkipCollateAndLikely(Expr*);
4959 int sqlite3CheckCollSeq(Parse *, CollSeq *);
4960 int sqlite3WritableSchema(sqlite3*);
4961 int sqlite3CheckObjectName(Parse*, const char*,const char*,const char*);
4962 void sqlite3VdbeSetChanges(sqlite3 *, i64);
4963 int sqlite3AddInt64(i64*,i64);
4964 int sqlite3SubInt64(i64*,i64);
4965 int sqlite3MulInt64(i64*,i64);
4966 int sqlite3AbsInt32(int);
4967 #ifdef SQLITE_ENABLE_8_3_NAMES
4968 void sqlite3FileSuffix3(const char*, char*);
4969 #else
4970 # define sqlite3FileSuffix3(X,Y)
4971 #endif
4972 u8 sqlite3GetBoolean(const char *z,u8);
4973 
4974 const void *sqlite3ValueText(sqlite3_value*, u8);
4975 int sqlite3ValueBytes(sqlite3_value*, u8);
4976 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
4977                         void(*)(void*));
4978 void sqlite3ValueSetNull(sqlite3_value*);
4979 void sqlite3ValueFree(sqlite3_value*);
4980 #ifndef SQLITE_UNTESTABLE
4981 void sqlite3ResultIntReal(sqlite3_context*);
4982 #endif
4983 sqlite3_value *sqlite3ValueNew(sqlite3 *);
4984 #ifndef SQLITE_OMIT_UTF16
4985 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
4986 #endif
4987 int sqlite3ValueFromExpr(sqlite3 *, const Expr *, u8, u8, sqlite3_value **);
4988 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
4989 #ifndef SQLITE_AMALGAMATION
4990 extern const unsigned char sqlite3OpcodeProperty[];
4991 extern const char sqlite3StrBINARY[];
4992 extern const unsigned char sqlite3StdTypeLen[];
4993 extern const char sqlite3StdTypeAffinity[];
4994 extern const char sqlite3StdTypeMap[];
4995 extern const char *sqlite3StdType[];
4996 extern const unsigned char sqlite3UpperToLower[];
4997 extern const unsigned char *sqlite3aLTb;
4998 extern const unsigned char *sqlite3aEQb;
4999 extern const unsigned char *sqlite3aGTb;
5000 extern const unsigned char sqlite3CtypeMap[];
5001 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
5002 extern FuncDefHash sqlite3BuiltinFunctions;
5003 #ifndef SQLITE_OMIT_WSD
5004 extern int sqlite3PendingByte;
5005 #endif
5006 #endif /* SQLITE_AMALGAMATION */
5007 #ifdef VDBE_PROFILE
5008 extern sqlite3_uint64 sqlite3NProfileCnt;
5009 #endif
5010 void sqlite3RootPageMoved(sqlite3*, int, Pgno, Pgno);
5011 void sqlite3Reindex(Parse*, Token*, Token*);
5012 void sqlite3AlterFunctions(void);
5013 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
5014 void sqlite3AlterRenameColumn(Parse*, SrcList*, Token*, Token*);
5015 int sqlite3GetToken(const unsigned char *, int *);
5016 void sqlite3NestedParse(Parse*, const char*, ...);
5017 void sqlite3ExpirePreparedStatements(sqlite3*, int);
5018 void sqlite3CodeRhsOfIN(Parse*, Expr*, int);
5019 int sqlite3CodeSubselect(Parse*, Expr*);
5020 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
5021 int sqlite3ExpandSubquery(Parse*, SrcItem*);
5022 void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
5023 int sqlite3MatchEName(
5024   const struct ExprList_item*,
5025   const char*,
5026   const char*,
5027   const char*
5028 );
5029 Bitmask sqlite3ExprColUsed(Expr*);
5030 u8 sqlite3StrIHash(const char*);
5031 int sqlite3ResolveExprNames(NameContext*, Expr*);
5032 int sqlite3ResolveExprListNames(NameContext*, ExprList*);
5033 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
5034 int sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
5035 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
5036 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
5037 void sqlite3AlterFinishAddColumn(Parse *, Token *);
5038 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
5039 void sqlite3AlterDropColumn(Parse*, SrcList*, const Token*);
5040 const void *sqlite3RenameTokenMap(Parse*, const void*, const Token*);
5041 void sqlite3RenameTokenRemap(Parse*, const void *pTo, const void *pFrom);
5042 void sqlite3RenameExprUnmap(Parse*, Expr*);
5043 void sqlite3RenameExprlistUnmap(Parse*, ExprList*);
5044 CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
5045 char sqlite3AffinityType(const char*, Column*);
5046 void sqlite3Analyze(Parse*, Token*, Token*);
5047 int sqlite3InvokeBusyHandler(BusyHandler*);
5048 int sqlite3FindDb(sqlite3*, Token*);
5049 int sqlite3FindDbName(sqlite3 *, const char *);
5050 int sqlite3AnalysisLoad(sqlite3*,int iDB);
5051 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
5052 void sqlite3DefaultRowEst(Index*);
5053 void sqlite3RegisterLikeFunctions(sqlite3*, int);
5054 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
5055 void sqlite3SchemaClear(void *);
5056 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
5057 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
5058 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
5059 void sqlite3KeyInfoUnref(KeyInfo*);
5060 KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
5061 KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
5062 KeyInfo *sqlite3KeyInfoFromExprList(Parse*, ExprList*, int, int);
5063 const char *sqlite3SelectOpName(int);
5064 int sqlite3HasExplicitNulls(Parse*, ExprList*);
5065 
5066 #ifdef SQLITE_DEBUG
5067 int sqlite3KeyInfoIsWriteable(KeyInfo*);
5068 #endif
5069 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
5070   void (*)(sqlite3_context*,int,sqlite3_value **),
5071   void (*)(sqlite3_context*,int,sqlite3_value **),
5072   void (*)(sqlite3_context*),
5073   void (*)(sqlite3_context*),
5074   void (*)(sqlite3_context*,int,sqlite3_value **),
5075   FuncDestructor *pDestructor
5076 );
5077 void sqlite3NoopDestructor(void*);
5078 void *sqlite3OomFault(sqlite3*);
5079 void sqlite3OomClear(sqlite3*);
5080 int sqlite3ApiExit(sqlite3 *db, int);
5081 int sqlite3OpenTempDatabase(Parse *);
5082 
5083 void sqlite3StrAccumInit(StrAccum*, sqlite3*, char*, int, int);
5084 int sqlite3StrAccumEnlarge(StrAccum*, int);
5085 char *sqlite3StrAccumFinish(StrAccum*);
5086 void sqlite3StrAccumSetError(StrAccum*, u8);
5087 void sqlite3ResultStrAccum(sqlite3_context*,StrAccum*);
5088 void sqlite3SelectDestInit(SelectDest*,int,int);
5089 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
5090 void sqlite3RecordErrorByteOffset(sqlite3*,const char*);
5091 void sqlite3RecordErrorOffsetOfExpr(sqlite3*,const Expr*);
5092 
5093 void sqlite3BackupRestart(sqlite3_backup *);
5094 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
5095 
5096 #ifndef SQLITE_OMIT_SUBQUERY
5097 int sqlite3ExprCheckIN(Parse*, Expr*);
5098 #else
5099 # define sqlite3ExprCheckIN(x,y) SQLITE_OK
5100 #endif
5101 
5102 #ifdef SQLITE_ENABLE_STAT4
5103 int sqlite3Stat4ProbeSetValue(
5104     Parse*,Index*,UnpackedRecord**,Expr*,int,int,int*);
5105 int sqlite3Stat4ValueFromExpr(Parse*, Expr*, u8, sqlite3_value**);
5106 void sqlite3Stat4ProbeFree(UnpackedRecord*);
5107 int sqlite3Stat4Column(sqlite3*, const void*, int, int, sqlite3_value**);
5108 char sqlite3IndexColumnAffinity(sqlite3*, Index*, int);
5109 #endif
5110 
5111 /*
5112 ** The interface to the LEMON-generated parser
5113 */
5114 #ifndef SQLITE_AMALGAMATION
5115   void *sqlite3ParserAlloc(void*(*)(u64), Parse*);
5116   void sqlite3ParserFree(void*, void(*)(void*));
5117 #endif
5118 void sqlite3Parser(void*, int, Token);
5119 int sqlite3ParserFallback(int);
5120 #ifdef YYTRACKMAXSTACKDEPTH
5121   int sqlite3ParserStackPeak(void*);
5122 #endif
5123 
5124 void sqlite3AutoLoadExtensions(sqlite3*);
5125 #ifndef SQLITE_OMIT_LOAD_EXTENSION
5126   void sqlite3CloseExtensions(sqlite3*);
5127 #else
5128 # define sqlite3CloseExtensions(X)
5129 #endif
5130 
5131 #ifndef SQLITE_OMIT_SHARED_CACHE
5132   void sqlite3TableLock(Parse *, int, Pgno, u8, const char *);
5133 #else
5134   #define sqlite3TableLock(v,w,x,y,z)
5135 #endif
5136 
5137 #ifdef SQLITE_TEST
5138   int sqlite3Utf8To8(unsigned char*);
5139 #endif
5140 
5141 #ifdef SQLITE_OMIT_VIRTUALTABLE
5142 #  define sqlite3VtabClear(D,T)
5143 #  define sqlite3VtabSync(X,Y) SQLITE_OK
5144 #  define sqlite3VtabRollback(X)
5145 #  define sqlite3VtabCommit(X)
5146 #  define sqlite3VtabInSync(db) 0
5147 #  define sqlite3VtabLock(X)
5148 #  define sqlite3VtabUnlock(X)
5149 #  define sqlite3VtabModuleUnref(D,X)
5150 #  define sqlite3VtabUnlockList(X)
5151 #  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
5152 #  define sqlite3GetVTable(X,Y)  ((VTable*)0)
5153 #else
5154    void sqlite3VtabClear(sqlite3 *db, Table*);
5155    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
5156    int sqlite3VtabSync(sqlite3 *db, Vdbe*);
5157    int sqlite3VtabRollback(sqlite3 *db);
5158    int sqlite3VtabCommit(sqlite3 *db);
5159    void sqlite3VtabLock(VTable *);
5160    void sqlite3VtabUnlock(VTable *);
5161    void sqlite3VtabModuleUnref(sqlite3*,Module*);
5162    void sqlite3VtabUnlockList(sqlite3*);
5163    int sqlite3VtabSavepoint(sqlite3 *, int, int);
5164    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
5165    VTable *sqlite3GetVTable(sqlite3*, Table*);
5166    Module *sqlite3VtabCreateModule(
5167      sqlite3*,
5168      const char*,
5169      const sqlite3_module*,
5170      void*,
5171      void(*)(void*)
5172    );
5173 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
5174 #endif
5175 int sqlite3ReadOnlyShadowTables(sqlite3 *db);
5176 #ifndef SQLITE_OMIT_VIRTUALTABLE
5177   int sqlite3ShadowTableName(sqlite3 *db, const char *zName);
5178   int sqlite3IsShadowTableOf(sqlite3*,Table*,const char*);
5179   void sqlite3MarkAllShadowTablesOf(sqlite3*, Table*);
5180 #else
5181 # define sqlite3ShadowTableName(A,B) 0
5182 # define sqlite3IsShadowTableOf(A,B,C) 0
5183 # define sqlite3MarkAllShadowTablesOf(A,B)
5184 #endif
5185 int sqlite3VtabEponymousTableInit(Parse*,Module*);
5186 void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
5187 void sqlite3VtabMakeWritable(Parse*,Table*);
5188 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
5189 void sqlite3VtabFinishParse(Parse*, Token*);
5190 void sqlite3VtabArgInit(Parse*);
5191 void sqlite3VtabArgExtend(Parse*, Token*);
5192 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
5193 int sqlite3VtabCallConnect(Parse*, Table*);
5194 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
5195 int sqlite3VtabBegin(sqlite3 *, VTable *);
5196 
5197 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
5198 #if (defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)) \
5199     && !defined(SQLITE_OMIT_VIRTUALTABLE)
5200   void sqlite3VtabUsesAllSchemas(sqlite3_index_info*);
5201 #endif
5202 sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
5203 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
5204 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
5205 void sqlite3ParseObjectInit(Parse*,sqlite3*);
5206 void sqlite3ParseObjectReset(Parse*);
5207 void *sqlite3ParserAddCleanup(Parse*,void(*)(sqlite3*,void*),void*);
5208 #ifdef SQLITE_ENABLE_NORMALIZE
5209 char *sqlite3Normalize(Vdbe*, const char*);
5210 #endif
5211 int sqlite3Reprepare(Vdbe*);
5212 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
5213 CollSeq *sqlite3ExprCompareCollSeq(Parse*,const Expr*);
5214 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, const Expr*, const Expr*);
5215 int sqlite3TempInMemory(const sqlite3*);
5216 const char *sqlite3JournalModename(int);
5217 #ifndef SQLITE_OMIT_WAL
5218   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
5219   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
5220 #endif
5221 #ifndef SQLITE_OMIT_CTE
5222   Cte *sqlite3CteNew(Parse*,Token*,ExprList*,Select*,u8);
5223   void sqlite3CteDelete(sqlite3*,Cte*);
5224   With *sqlite3WithAdd(Parse*,With*,Cte*);
5225   void sqlite3WithDelete(sqlite3*,With*);
5226   With *sqlite3WithPush(Parse*, With*, u8);
5227 #else
5228 # define sqlite3CteNew(P,T,E,S)   ((void*)0)
5229 # define sqlite3CteDelete(D,C)
5230 # define sqlite3CteWithAdd(P,W,C) ((void*)0)
5231 # define sqlite3WithDelete(x,y)
5232 # define sqlite3WithPush(x,y,z) ((void*)0)
5233 #endif
5234 #ifndef SQLITE_OMIT_UPSERT
5235   Upsert *sqlite3UpsertNew(sqlite3*,ExprList*,Expr*,ExprList*,Expr*,Upsert*);
5236   void sqlite3UpsertDelete(sqlite3*,Upsert*);
5237   Upsert *sqlite3UpsertDup(sqlite3*,Upsert*);
5238   int sqlite3UpsertAnalyzeTarget(Parse*,SrcList*,Upsert*);
5239   void sqlite3UpsertDoUpdate(Parse*,Upsert*,Table*,Index*,int);
5240   Upsert *sqlite3UpsertOfIndex(Upsert*,Index*);
5241   int sqlite3UpsertNextIsIPK(Upsert*);
5242 #else
5243 #define sqlite3UpsertNew(u,v,w,x,y,z) ((Upsert*)0)
5244 #define sqlite3UpsertDelete(x,y)
5245 #define sqlite3UpsertDup(x,y)         ((Upsert*)0)
5246 #define sqlite3UpsertOfIndex(x,y)     ((Upsert*)0)
5247 #define sqlite3UpsertNextIsIPK(x)     0
5248 #endif
5249 
5250 
5251 /* Declarations for functions in fkey.c. All of these are replaced by
5252 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
5253 ** key functionality is available. If OMIT_TRIGGER is defined but
5254 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
5255 ** this case foreign keys are parsed, but no other functionality is
5256 ** provided (enforcement of FK constraints requires the triggers sub-system).
5257 */
5258 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
5259   void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
5260   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
5261   void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
5262   int sqlite3FkRequired(Parse*, Table*, int*, int);
5263   u32 sqlite3FkOldmask(Parse*, Table*);
5264   FKey *sqlite3FkReferences(Table *);
5265   void sqlite3FkClearTriggerCache(sqlite3*,int);
5266 #else
5267   #define sqlite3FkActions(a,b,c,d,e,f)
5268   #define sqlite3FkCheck(a,b,c,d,e,f)
5269   #define sqlite3FkDropTable(a,b,c)
5270   #define sqlite3FkOldmask(a,b)         0
5271   #define sqlite3FkRequired(a,b,c,d)    0
5272   #define sqlite3FkReferences(a)        0
5273   #define sqlite3FkClearTriggerCache(a,b)
5274 #endif
5275 #ifndef SQLITE_OMIT_FOREIGN_KEY
5276   void sqlite3FkDelete(sqlite3 *, Table*);
5277   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
5278 #else
5279   #define sqlite3FkDelete(a,b)
5280   #define sqlite3FkLocateIndex(a,b,c,d,e)
5281 #endif
5282 
5283 
5284 /*
5285 ** Available fault injectors.  Should be numbered beginning with 0.
5286 */
5287 #define SQLITE_FAULTINJECTOR_MALLOC     0
5288 #define SQLITE_FAULTINJECTOR_COUNT      1
5289 
5290 /*
5291 ** The interface to the code in fault.c used for identifying "benign"
5292 ** malloc failures. This is only present if SQLITE_UNTESTABLE
5293 ** is not defined.
5294 */
5295 #ifndef SQLITE_UNTESTABLE
5296   void sqlite3BeginBenignMalloc(void);
5297   void sqlite3EndBenignMalloc(void);
5298 #else
5299   #define sqlite3BeginBenignMalloc()
5300   #define sqlite3EndBenignMalloc()
5301 #endif
5302 
5303 /*
5304 ** Allowed return values from sqlite3FindInIndex()
5305 */
5306 #define IN_INDEX_ROWID        1   /* Search the rowid of the table */
5307 #define IN_INDEX_EPH          2   /* Search an ephemeral b-tree */
5308 #define IN_INDEX_INDEX_ASC    3   /* Existing index ASCENDING */
5309 #define IN_INDEX_INDEX_DESC   4   /* Existing index DESCENDING */
5310 #define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
5311 /*
5312 ** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
5313 */
5314 #define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
5315 #define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
5316 #define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
5317 int sqlite3FindInIndex(Parse *, Expr *, u32, int*, int*, int*);
5318 
5319 int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
5320 int sqlite3JournalSize(sqlite3_vfs *);
5321 #if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
5322  || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
5323   int sqlite3JournalCreate(sqlite3_file *);
5324 #endif
5325 
5326 int sqlite3JournalIsInMemory(sqlite3_file *p);
5327 void sqlite3MemJournalOpen(sqlite3_file *);
5328 
5329 void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p);
5330 #if SQLITE_MAX_EXPR_DEPTH>0
5331   int sqlite3SelectExprHeight(const Select *);
5332   int sqlite3ExprCheckHeight(Parse*, int);
5333 #else
5334   #define sqlite3SelectExprHeight(x) 0
5335   #define sqlite3ExprCheckHeight(x,y)
5336 #endif
5337 
5338 u32 sqlite3Get4byte(const u8*);
5339 void sqlite3Put4byte(u8*, u32);
5340 
5341 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
5342   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
5343   void sqlite3ConnectionUnlocked(sqlite3 *db);
5344   void sqlite3ConnectionClosed(sqlite3 *db);
5345 #else
5346   #define sqlite3ConnectionBlocked(x,y)
5347   #define sqlite3ConnectionUnlocked(x)
5348   #define sqlite3ConnectionClosed(x)
5349 #endif
5350 
5351 #ifdef SQLITE_DEBUG
5352   void sqlite3ParserTrace(FILE*, char *);
5353 #endif
5354 #if defined(YYCOVERAGE)
5355   int sqlite3ParserCoverage(FILE*);
5356 #endif
5357 
5358 /*
5359 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
5360 ** sqlite3IoTrace is a pointer to a printf-like routine used to
5361 ** print I/O tracing messages.
5362 */
5363 #ifdef SQLITE_ENABLE_IOTRACE
5364 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
5365   void sqlite3VdbeIOTraceSql(Vdbe*);
5366 SQLITE_API SQLITE_EXTERN void (SQLITE_CDECL *sqlite3IoTrace)(const char*,...);
5367 #else
5368 # define IOTRACE(A)
5369 # define sqlite3VdbeIOTraceSql(X)
5370 #endif
5371 
5372 /*
5373 ** These routines are available for the mem2.c debugging memory allocator
5374 ** only.  They are used to verify that different "types" of memory
5375 ** allocations are properly tracked by the system.
5376 **
5377 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
5378 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
5379 ** a single bit set.
5380 **
5381 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
5382 ** argument match the type set by the previous sqlite3MemdebugSetType().
5383 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
5384 **
5385 ** sqlite3MemdebugNoType() returns true if none of the bits in its second
5386 ** argument match the type set by the previous sqlite3MemdebugSetType().
5387 **
5388 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
5389 ** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
5390 ** it might have been allocated by lookaside, except the allocation was
5391 ** too large or lookaside was already full.  It is important to verify
5392 ** that allocations that might have been satisfied by lookaside are not
5393 ** passed back to non-lookaside free() routines.  Asserts such as the
5394 ** example above are placed on the non-lookaside free() routines to verify
5395 ** this constraint.
5396 **
5397 ** All of this is no-op for a production build.  It only comes into
5398 ** play when the SQLITE_MEMDEBUG compile-time option is used.
5399 */
5400 #ifdef SQLITE_MEMDEBUG
5401   void sqlite3MemdebugSetType(void*,u8);
5402   int sqlite3MemdebugHasType(const void*,u8);
5403   int sqlite3MemdebugNoType(const void*,u8);
5404 #else
5405 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
5406 # define sqlite3MemdebugHasType(X,Y)  1
5407 # define sqlite3MemdebugNoType(X,Y)   1
5408 #endif
5409 #define MEMTYPE_HEAP       0x01  /* General heap allocations */
5410 #define MEMTYPE_LOOKASIDE  0x02  /* Heap that might have been lookaside */
5411 #define MEMTYPE_PCACHE     0x04  /* Page cache allocations */
5412 
5413 /*
5414 ** Threading interface
5415 */
5416 #if SQLITE_MAX_WORKER_THREADS>0
5417 int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
5418 int sqlite3ThreadJoin(SQLiteThread*, void**);
5419 #endif
5420 
5421 #if defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)
5422 int sqlite3DbpageRegister(sqlite3*);
5423 #endif
5424 #if defined(SQLITE_ENABLE_DBSTAT_VTAB) || defined(SQLITE_TEST)
5425 int sqlite3DbstatRegister(sqlite3*);
5426 #endif
5427 
5428 int sqlite3ExprVectorSize(const Expr *pExpr);
5429 int sqlite3ExprIsVector(const Expr *pExpr);
5430 Expr *sqlite3VectorFieldSubexpr(Expr*, int);
5431 Expr *sqlite3ExprForVectorField(Parse*,Expr*,int,int);
5432 void sqlite3VectorErrorMsg(Parse*, Expr*);
5433 
5434 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
5435 const char **sqlite3CompileOptions(int *pnOpt);
5436 #endif
5437 
5438 #endif /* SQLITEINT_H */
5439