xref: /sqlite-3.40.0/src/sqliteInt.h (revision 0cb735b9)
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 /* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
185 ** first in QNX.  Also, the _USE_32BIT_TIME_T macro must appear first for
186 ** MinGW.
187 */
188 #include "sqlite3.h"
189 
190 /*
191 ** Include the configuration header output by 'configure' if we're using the
192 ** autoconf-based build
193 */
194 #if defined(_HAVE_SQLITE_CONFIG_H) && !defined(SQLITECONFIG_H)
195 #include "config.h"
196 #define SQLITECONFIG_H 1
197 #endif
198 
199 #include "sqliteLimit.h"
200 
201 /* Disable nuisance warnings on Borland compilers */
202 #if defined(__BORLANDC__)
203 #pragma warn -rch /* unreachable code */
204 #pragma warn -ccc /* Condition is always true or false */
205 #pragma warn -aus /* Assigned value is never used */
206 #pragma warn -csu /* Comparing signed and unsigned */
207 #pragma warn -spa /* Suspicious pointer arithmetic */
208 #endif
209 
210 /*
211 ** WAL mode depends on atomic aligned 32-bit loads and stores in a few
212 ** places.  The following macros try to make this explicit.
213 */
214 #ifndef __has_extension
215 # define __has_extension(x) 0     /* compatibility with non-clang compilers */
216 #endif
217 #if GCC_VERSION>=4007000 || __has_extension(c_atomic)
218 # define AtomicLoad(PTR)       __atomic_load_n((PTR),__ATOMIC_RELAXED)
219 # define AtomicStore(PTR,VAL)  __atomic_store_n((PTR),(VAL),__ATOMIC_RELAXED)
220 #else
221 # define AtomicLoad(PTR)       (*(PTR))
222 # define AtomicStore(PTR,VAL)  (*(PTR) = (VAL))
223 #endif
224 
225 /*
226 ** Include standard header files as necessary
227 */
228 #ifdef HAVE_STDINT_H
229 #include <stdint.h>
230 #endif
231 #ifdef HAVE_INTTYPES_H
232 #include <inttypes.h>
233 #endif
234 
235 /*
236 ** The following macros are used to cast pointers to integers and
237 ** integers to pointers.  The way you do this varies from one compiler
238 ** to the next, so we have developed the following set of #if statements
239 ** to generate appropriate macros for a wide range of compilers.
240 **
241 ** The correct "ANSI" way to do this is to use the intptr_t type.
242 ** Unfortunately, that typedef is not available on all compilers, or
243 ** if it is available, it requires an #include of specific headers
244 ** that vary from one machine to the next.
245 **
246 ** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
247 ** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
248 ** So we have to define the macros in different ways depending on the
249 ** compiler.
250 */
251 #if defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
252 # define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
253 # define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
254 #elif defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
255 # define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
256 # define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
257 #elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
258 # define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
259 # define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
260 #else                          /* Generates a warning - but it always works */
261 # define SQLITE_INT_TO_PTR(X)  ((void*)(X))
262 # define SQLITE_PTR_TO_INT(X)  ((int)(X))
263 #endif
264 
265 /*
266 ** A macro to hint to the compiler that a function should not be
267 ** inlined.
268 */
269 #if defined(__GNUC__)
270 #  define SQLITE_NOINLINE  __attribute__((noinline))
271 #elif defined(_MSC_VER) && _MSC_VER>=1310
272 #  define SQLITE_NOINLINE  __declspec(noinline)
273 #else
274 #  define SQLITE_NOINLINE
275 #endif
276 
277 /*
278 ** Make sure that the compiler intrinsics we desire are enabled when
279 ** compiling with an appropriate version of MSVC unless prevented by
280 ** the SQLITE_DISABLE_INTRINSIC define.
281 */
282 #if !defined(SQLITE_DISABLE_INTRINSIC)
283 #  if defined(_MSC_VER) && _MSC_VER>=1400
284 #    if !defined(_WIN32_WCE)
285 #      include <intrin.h>
286 #      pragma intrinsic(_byteswap_ushort)
287 #      pragma intrinsic(_byteswap_ulong)
288 #      pragma intrinsic(_byteswap_uint64)
289 #      pragma intrinsic(_ReadWriteBarrier)
290 #    else
291 #      include <cmnintrin.h>
292 #    endif
293 #  endif
294 #endif
295 
296 /*
297 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
298 ** 0 means mutexes are permanently disable and the library is never
299 ** threadsafe.  1 means the library is serialized which is the highest
300 ** level of threadsafety.  2 means the library is multithreaded - multiple
301 ** threads can use SQLite as long as no two threads try to use the same
302 ** database connection at the same time.
303 **
304 ** Older versions of SQLite used an optional THREADSAFE macro.
305 ** We support that for legacy.
306 **
307 ** To ensure that the correct value of "THREADSAFE" is reported when querying
308 ** for compile-time options at runtime (e.g. "PRAGMA compile_options"), this
309 ** logic is partially replicated in ctime.c. If it is updated here, it should
310 ** also be updated there.
311 */
312 #if !defined(SQLITE_THREADSAFE)
313 # if defined(THREADSAFE)
314 #   define SQLITE_THREADSAFE THREADSAFE
315 # else
316 #   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
317 # endif
318 #endif
319 
320 /*
321 ** Powersafe overwrite is on by default.  But can be turned off using
322 ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
323 */
324 #ifndef SQLITE_POWERSAFE_OVERWRITE
325 # define SQLITE_POWERSAFE_OVERWRITE 1
326 #endif
327 
328 /*
329 ** EVIDENCE-OF: R-25715-37072 Memory allocation statistics are enabled by
330 ** default unless SQLite is compiled with SQLITE_DEFAULT_MEMSTATUS=0 in
331 ** which case memory allocation statistics are disabled by default.
332 */
333 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
334 # define SQLITE_DEFAULT_MEMSTATUS 1
335 #endif
336 
337 /*
338 ** Exactly one of the following macros must be defined in order to
339 ** specify which memory allocation subsystem to use.
340 **
341 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
342 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
343 **     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
344 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
345 **
346 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
347 ** assert() macro is enabled, each call into the Win32 native heap subsystem
348 ** will cause HeapValidate to be called.  If heap validation should fail, an
349 ** assertion will be triggered.
350 **
351 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
352 ** the default.
353 */
354 #if defined(SQLITE_SYSTEM_MALLOC) \
355   + defined(SQLITE_WIN32_MALLOC) \
356   + defined(SQLITE_ZERO_MALLOC) \
357   + defined(SQLITE_MEMDEBUG)>1
358 # error "Two or more of the following compile-time configuration options\
359  are defined but at most one is allowed:\
360  SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
361  SQLITE_ZERO_MALLOC"
362 #endif
363 #if defined(SQLITE_SYSTEM_MALLOC) \
364   + defined(SQLITE_WIN32_MALLOC) \
365   + defined(SQLITE_ZERO_MALLOC) \
366   + defined(SQLITE_MEMDEBUG)==0
367 # define SQLITE_SYSTEM_MALLOC 1
368 #endif
369 
370 /*
371 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
372 ** sizes of memory allocations below this value where possible.
373 */
374 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
375 # define SQLITE_MALLOC_SOFT_LIMIT 1024
376 #endif
377 
378 /*
379 ** We need to define _XOPEN_SOURCE as follows in order to enable
380 ** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
381 ** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
382 ** it.
383 */
384 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
385 #  define _XOPEN_SOURCE 600
386 #endif
387 
388 /*
389 ** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
390 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
391 ** make it true by defining or undefining NDEBUG.
392 **
393 ** Setting NDEBUG makes the code smaller and faster by disabling the
394 ** assert() statements in the code.  So we want the default action
395 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
396 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
397 ** feature.
398 */
399 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
400 # define NDEBUG 1
401 #endif
402 #if defined(NDEBUG) && defined(SQLITE_DEBUG)
403 # undef NDEBUG
404 #endif
405 
406 /*
407 ** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
408 */
409 #if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
410 # define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
411 #endif
412 
413 /*
414 ** The testcase() macro is used to aid in coverage testing.  When
415 ** doing coverage testing, the condition inside the argument to
416 ** testcase() must be evaluated both true and false in order to
417 ** get full branch coverage.  The testcase() macro is inserted
418 ** to help ensure adequate test coverage in places where simple
419 ** condition/decision coverage is inadequate.  For example, testcase()
420 ** can be used to make sure boundary values are tested.  For
421 ** bitmask tests, testcase() can be used to make sure each bit
422 ** is significant and used at least once.  On switch statements
423 ** where multiple cases go to the same block of code, testcase()
424 ** can insure that all cases are evaluated.
425 **
426 */
427 #ifdef SQLITE_COVERAGE_TEST
428   void sqlite3Coverage(int);
429 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
430 #else
431 # define testcase(X)
432 #endif
433 
434 /*
435 ** The TESTONLY macro is used to enclose variable declarations or
436 ** other bits of code that are needed to support the arguments
437 ** within testcase() and assert() macros.
438 */
439 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
440 # define TESTONLY(X)  X
441 #else
442 # define TESTONLY(X)
443 #endif
444 
445 /*
446 ** Sometimes we need a small amount of code such as a variable initialization
447 ** to setup for a later assert() statement.  We do not want this code to
448 ** appear when assert() is disabled.  The following macro is therefore
449 ** used to contain that setup code.  The "VVA" acronym stands for
450 ** "Verification, Validation, and Accreditation".  In other words, the
451 ** code within VVA_ONLY() will only run during verification processes.
452 */
453 #ifndef NDEBUG
454 # define VVA_ONLY(X)  X
455 #else
456 # define VVA_ONLY(X)
457 #endif
458 
459 /*
460 ** The ALWAYS and NEVER macros surround boolean expressions which
461 ** are intended to always be true or false, respectively.  Such
462 ** expressions could be omitted from the code completely.  But they
463 ** are included in a few cases in order to enhance the resilience
464 ** of SQLite to unexpected behavior - to make the code "self-healing"
465 ** or "ductile" rather than being "brittle" and crashing at the first
466 ** hint of unplanned behavior.
467 **
468 ** In other words, ALWAYS and NEVER are added for defensive code.
469 **
470 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
471 ** be true and false so that the unreachable code they specify will
472 ** not be counted as untested code.
473 */
474 #if defined(SQLITE_COVERAGE_TEST) || defined(SQLITE_MUTATION_TEST)
475 # define ALWAYS(X)      (1)
476 # define NEVER(X)       (0)
477 #elif !defined(NDEBUG)
478 # define ALWAYS(X)      ((X)?1:(assert(0),0))
479 # define NEVER(X)       ((X)?(assert(0),1):0)
480 #else
481 # define ALWAYS(X)      (X)
482 # define NEVER(X)       (X)
483 #endif
484 
485 /*
486 ** The harmless(X) macro indicates that expression X is usually false
487 ** but can be true without causing any problems, but we don't know of
488 ** any way to cause X to be true.
489 **
490 ** In debugging and testing builds, this macro will abort if X is ever
491 ** true.  In this way, developers are alerted to a possible test case
492 ** that causes X to be true.  If a harmless macro ever fails, that is
493 ** an opportunity to change the macro into a testcase() and add a new
494 ** test case to the test suite.
495 **
496 ** For normal production builds, harmless(X) is a no-op, since it does
497 ** not matter whether expression X is true or false.
498 */
499 #ifdef SQLITE_DEBUG
500 # define harmless(X)  assert(!(X));
501 #else
502 # define harmless(X)
503 #endif
504 
505 /*
506 ** Some conditionals are optimizations only.  In other words, if the
507 ** conditionals are replaced with a constant 1 (true) or 0 (false) then
508 ** the correct answer is still obtained, though perhaps not as quickly.
509 **
510 ** The following macros mark these optimizations conditionals.
511 */
512 #if defined(SQLITE_MUTATION_TEST)
513 # define OK_IF_ALWAYS_TRUE(X)  (1)
514 # define OK_IF_ALWAYS_FALSE(X) (0)
515 #else
516 # define OK_IF_ALWAYS_TRUE(X)  (X)
517 # define OK_IF_ALWAYS_FALSE(X) (X)
518 #endif
519 
520 /*
521 ** Some malloc failures are only possible if SQLITE_TEST_REALLOC_STRESS is
522 ** defined.  We need to defend against those failures when testing with
523 ** SQLITE_TEST_REALLOC_STRESS, but we don't want the unreachable branches
524 ** during a normal build.  The following macro can be used to disable tests
525 ** that are always false except when SQLITE_TEST_REALLOC_STRESS is set.
526 */
527 #if defined(SQLITE_TEST_REALLOC_STRESS)
528 # define ONLY_IF_REALLOC_STRESS(X)  (X)
529 #elif !defined(NDEBUG)
530 # define ONLY_IF_REALLOC_STRESS(X)  ((X)?(assert(0),1):0)
531 #else
532 # define ONLY_IF_REALLOC_STRESS(X)  (0)
533 #endif
534 
535 /*
536 ** Declarations used for tracing the operating system interfaces.
537 */
538 #if defined(SQLITE_FORCE_OS_TRACE) || defined(SQLITE_TEST) || \
539     (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
540   extern int sqlite3OSTrace;
541 # define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
542 # define SQLITE_HAVE_OS_TRACE
543 #else
544 # define OSTRACE(X)
545 # undef  SQLITE_HAVE_OS_TRACE
546 #endif
547 
548 /*
549 ** Is the sqlite3ErrName() function needed in the build?  Currently,
550 ** it is needed by "mutex_w32.c" (when debugging), "os_win.c" (when
551 ** OSTRACE is enabled), and by several "test*.c" files (which are
552 ** compiled using SQLITE_TEST).
553 */
554 #if defined(SQLITE_HAVE_OS_TRACE) || defined(SQLITE_TEST) || \
555     (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
556 # define SQLITE_NEED_ERR_NAME
557 #else
558 # undef  SQLITE_NEED_ERR_NAME
559 #endif
560 
561 /*
562 ** SQLITE_ENABLE_EXPLAIN_COMMENTS is incompatible with SQLITE_OMIT_EXPLAIN
563 */
564 #ifdef SQLITE_OMIT_EXPLAIN
565 # undef SQLITE_ENABLE_EXPLAIN_COMMENTS
566 #endif
567 
568 /*
569 ** Return true (non-zero) if the input is an integer that is too large
570 ** to fit in 32-bits.  This macro is used inside of various testcase()
571 ** macros to verify that we have tested SQLite for large-file support.
572 */
573 #define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
574 
575 /*
576 ** The macro unlikely() is a hint that surrounds a boolean
577 ** expression that is usually false.  Macro likely() surrounds
578 ** a boolean expression that is usually true.  These hints could,
579 ** in theory, be used by the compiler to generate better code, but
580 ** currently they are just comments for human readers.
581 */
582 #define likely(X)    (X)
583 #define unlikely(X)  (X)
584 
585 #include "hash.h"
586 #include "parse.h"
587 #include <stdio.h>
588 #include <stdlib.h>
589 #include <string.h>
590 #include <assert.h>
591 #include <stddef.h>
592 
593 /*
594 ** Use a macro to replace memcpy() if compiled with SQLITE_INLINE_MEMCPY.
595 ** This allows better measurements of where memcpy() is used when running
596 ** cachegrind.  But this macro version of memcpy() is very slow so it
597 ** should not be used in production.  This is a performance measurement
598 ** hack only.
599 */
600 #ifdef SQLITE_INLINE_MEMCPY
601 # define memcpy(D,S,N) {char*xxd=(char*)(D);const char*xxs=(const char*)(S);\
602                         int xxn=(N);while(xxn-->0)*(xxd++)=*(xxs++);}
603 #endif
604 
605 /*
606 ** If compiling for a processor that lacks floating point support,
607 ** substitute integer for floating-point
608 */
609 #ifdef SQLITE_OMIT_FLOATING_POINT
610 # define double sqlite_int64
611 # define float sqlite_int64
612 # define LONGDOUBLE_TYPE sqlite_int64
613 # ifndef SQLITE_BIG_DBL
614 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
615 # endif
616 # define SQLITE_OMIT_DATETIME_FUNCS 1
617 # define SQLITE_OMIT_TRACE 1
618 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
619 # undef SQLITE_HAVE_ISNAN
620 #endif
621 #ifndef SQLITE_BIG_DBL
622 # define SQLITE_BIG_DBL (1e99)
623 #endif
624 
625 /*
626 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
627 ** afterward. Having this macro allows us to cause the C compiler
628 ** to omit code used by TEMP tables without messy #ifndef statements.
629 */
630 #ifdef SQLITE_OMIT_TEMPDB
631 #define OMIT_TEMPDB 1
632 #else
633 #define OMIT_TEMPDB 0
634 #endif
635 
636 /*
637 ** The "file format" number is an integer that is incremented whenever
638 ** the VDBE-level file format changes.  The following macros define the
639 ** the default file format for new databases and the maximum file format
640 ** that the library can read.
641 */
642 #define SQLITE_MAX_FILE_FORMAT 4
643 #ifndef SQLITE_DEFAULT_FILE_FORMAT
644 # define SQLITE_DEFAULT_FILE_FORMAT 4
645 #endif
646 
647 /*
648 ** Determine whether triggers are recursive by default.  This can be
649 ** changed at run-time using a pragma.
650 */
651 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
652 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
653 #endif
654 
655 /*
656 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
657 ** on the command-line
658 */
659 #ifndef SQLITE_TEMP_STORE
660 # define SQLITE_TEMP_STORE 1
661 #endif
662 
663 /*
664 ** If no value has been provided for SQLITE_MAX_WORKER_THREADS, or if
665 ** SQLITE_TEMP_STORE is set to 3 (never use temporary files), set it
666 ** to zero.
667 */
668 #if SQLITE_TEMP_STORE==3 || SQLITE_THREADSAFE==0
669 # undef SQLITE_MAX_WORKER_THREADS
670 # define SQLITE_MAX_WORKER_THREADS 0
671 #endif
672 #ifndef SQLITE_MAX_WORKER_THREADS
673 # define SQLITE_MAX_WORKER_THREADS 8
674 #endif
675 #ifndef SQLITE_DEFAULT_WORKER_THREADS
676 # define SQLITE_DEFAULT_WORKER_THREADS 0
677 #endif
678 #if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
679 # undef SQLITE_MAX_WORKER_THREADS
680 # define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
681 #endif
682 
683 /*
684 ** The default initial allocation for the pagecache when using separate
685 ** pagecaches for each database connection.  A positive number is the
686 ** number of pages.  A negative number N translations means that a buffer
687 ** of -1024*N bytes is allocated and used for as many pages as it will hold.
688 **
689 ** The default value of "20" was choosen to minimize the run-time of the
690 ** speedtest1 test program with options: --shrink-memory --reprepare
691 */
692 #ifndef SQLITE_DEFAULT_PCACHE_INITSZ
693 # define SQLITE_DEFAULT_PCACHE_INITSZ 20
694 #endif
695 
696 /*
697 ** Default value for the SQLITE_CONFIG_SORTERREF_SIZE option.
698 */
699 #ifndef SQLITE_DEFAULT_SORTERREF_SIZE
700 # define SQLITE_DEFAULT_SORTERREF_SIZE 0x7fffffff
701 #endif
702 
703 /*
704 ** The compile-time options SQLITE_MMAP_READWRITE and
705 ** SQLITE_ENABLE_BATCH_ATOMIC_WRITE are not compatible with one another.
706 ** You must choose one or the other (or neither) but not both.
707 */
708 #if defined(SQLITE_MMAP_READWRITE) && defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
709 #error Cannot use both SQLITE_MMAP_READWRITE and SQLITE_ENABLE_BATCH_ATOMIC_WRITE
710 #endif
711 
712 /*
713 ** GCC does not define the offsetof() macro so we'll have to do it
714 ** ourselves.
715 */
716 #ifndef offsetof
717 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
718 #endif
719 
720 /*
721 ** Macros to compute minimum and maximum of two numbers.
722 */
723 #ifndef MIN
724 # define MIN(A,B) ((A)<(B)?(A):(B))
725 #endif
726 #ifndef MAX
727 # define MAX(A,B) ((A)>(B)?(A):(B))
728 #endif
729 
730 /*
731 ** Swap two objects of type TYPE.
732 */
733 #define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
734 
735 /*
736 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
737 ** not, there are still machines out there that use EBCDIC.)
738 */
739 #if 'A' == '\301'
740 # define SQLITE_EBCDIC 1
741 #else
742 # define SQLITE_ASCII 1
743 #endif
744 
745 /*
746 ** Integers of known sizes.  These typedefs might change for architectures
747 ** where the sizes very.  Preprocessor macros are available so that the
748 ** types can be conveniently redefined at compile-type.  Like this:
749 **
750 **         cc '-DUINTPTR_TYPE=long long int' ...
751 */
752 #ifndef UINT32_TYPE
753 # ifdef HAVE_UINT32_T
754 #  define UINT32_TYPE uint32_t
755 # else
756 #  define UINT32_TYPE unsigned int
757 # endif
758 #endif
759 #ifndef UINT16_TYPE
760 # ifdef HAVE_UINT16_T
761 #  define UINT16_TYPE uint16_t
762 # else
763 #  define UINT16_TYPE unsigned short int
764 # endif
765 #endif
766 #ifndef INT16_TYPE
767 # ifdef HAVE_INT16_T
768 #  define INT16_TYPE int16_t
769 # else
770 #  define INT16_TYPE short int
771 # endif
772 #endif
773 #ifndef UINT8_TYPE
774 # ifdef HAVE_UINT8_T
775 #  define UINT8_TYPE uint8_t
776 # else
777 #  define UINT8_TYPE unsigned char
778 # endif
779 #endif
780 #ifndef INT8_TYPE
781 # ifdef HAVE_INT8_T
782 #  define INT8_TYPE int8_t
783 # else
784 #  define INT8_TYPE signed char
785 # endif
786 #endif
787 #ifndef LONGDOUBLE_TYPE
788 # define LONGDOUBLE_TYPE long double
789 #endif
790 typedef sqlite_int64 i64;          /* 8-byte signed integer */
791 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
792 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
793 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
794 typedef INT16_TYPE i16;            /* 2-byte signed integer */
795 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
796 typedef INT8_TYPE i8;              /* 1-byte signed integer */
797 
798 /*
799 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
800 ** that can be stored in a u32 without loss of data.  The value
801 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
802 ** have to specify the value in the less intuitive manner shown:
803 */
804 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
805 
806 /*
807 ** The datatype used to store estimates of the number of rows in a
808 ** table or index.  This is an unsigned integer type.  For 99.9% of
809 ** the world, a 32-bit integer is sufficient.  But a 64-bit integer
810 ** can be used at compile-time if desired.
811 */
812 #ifdef SQLITE_64BIT_STATS
813  typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
814 #else
815  typedef u32 tRowcnt;    /* 32-bit is the default */
816 #endif
817 
818 /*
819 ** Estimated quantities used for query planning are stored as 16-bit
820 ** logarithms.  For quantity X, the value stored is 10*log2(X).  This
821 ** gives a possible range of values of approximately 1.0e986 to 1e-986.
822 ** But the allowed values are "grainy".  Not every value is representable.
823 ** For example, quantities 16 and 17 are both represented by a LogEst
824 ** of 40.  However, since LogEst quantities are suppose to be estimates,
825 ** not exact values, this imprecision is not a problem.
826 **
827 ** "LogEst" is short for "Logarithmic Estimate".
828 **
829 ** Examples:
830 **      1 -> 0              20 -> 43          10000 -> 132
831 **      2 -> 10             25 -> 46          25000 -> 146
832 **      3 -> 16            100 -> 66        1000000 -> 199
833 **      4 -> 20           1000 -> 99        1048576 -> 200
834 **     10 -> 33           1024 -> 100    4294967296 -> 320
835 **
836 ** The LogEst can be negative to indicate fractional values.
837 ** Examples:
838 **
839 **    0.5 -> -10           0.1 -> -33        0.0625 -> -40
840 */
841 typedef INT16_TYPE LogEst;
842 
843 /*
844 ** Set the SQLITE_PTRSIZE macro to the number of bytes in a pointer
845 */
846 #ifndef SQLITE_PTRSIZE
847 # if defined(__SIZEOF_POINTER__)
848 #   define SQLITE_PTRSIZE __SIZEOF_POINTER__
849 # elif defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
850        defined(_M_ARM)   || defined(__arm__)    || defined(__x86)   ||    \
851       (defined(__TOS_AIX__) && !defined(__64BIT__))
852 #   define SQLITE_PTRSIZE 4
853 # else
854 #   define SQLITE_PTRSIZE 8
855 # endif
856 #endif
857 
858 /* The uptr type is an unsigned integer large enough to hold a pointer
859 */
860 #if defined(HAVE_STDINT_H)
861   typedef uintptr_t uptr;
862 #elif SQLITE_PTRSIZE==4
863   typedef u32 uptr;
864 #else
865   typedef u64 uptr;
866 #endif
867 
868 /*
869 ** The SQLITE_WITHIN(P,S,E) macro checks to see if pointer P points to
870 ** something between S (inclusive) and E (exclusive).
871 **
872 ** In other words, S is a buffer and E is a pointer to the first byte after
873 ** the end of buffer S.  This macro returns true if P points to something
874 ** contained within the buffer S.
875 */
876 #define SQLITE_WITHIN(P,S,E) (((uptr)(P)>=(uptr)(S))&&((uptr)(P)<(uptr)(E)))
877 
878 
879 /*
880 ** Macros to determine whether the machine is big or little endian,
881 ** and whether or not that determination is run-time or compile-time.
882 **
883 ** For best performance, an attempt is made to guess at the byte-order
884 ** using C-preprocessor macros.  If that is unsuccessful, or if
885 ** -DSQLITE_BYTEORDER=0 is set, then byte-order is determined
886 ** at run-time.
887 */
888 #ifndef SQLITE_BYTEORDER
889 # if defined(i386)      || defined(__i386__)      || defined(_M_IX86) ||    \
890      defined(__x86_64)  || defined(__x86_64__)    || defined(_M_X64)  ||    \
891      defined(_M_AMD64)  || defined(_M_ARM)        || defined(__x86)   ||    \
892      defined(__ARMEL__) || defined(__AARCH64EL__) || defined(_M_ARM64)
893 #   define SQLITE_BYTEORDER    1234
894 # elif defined(sparc)     || defined(__ppc__) || \
895        defined(__ARMEB__) || defined(__AARCH64EB__)
896 #   define SQLITE_BYTEORDER    4321
897 # else
898 #   define SQLITE_BYTEORDER 0
899 # endif
900 #endif
901 #if SQLITE_BYTEORDER==4321
902 # define SQLITE_BIGENDIAN    1
903 # define SQLITE_LITTLEENDIAN 0
904 # define SQLITE_UTF16NATIVE  SQLITE_UTF16BE
905 #elif SQLITE_BYTEORDER==1234
906 # define SQLITE_BIGENDIAN    0
907 # define SQLITE_LITTLEENDIAN 1
908 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
909 #else
910 # ifdef SQLITE_AMALGAMATION
911   const int sqlite3one = 1;
912 # else
913   extern const int sqlite3one;
914 # endif
915 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
916 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
917 # define SQLITE_UTF16NATIVE  (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
918 #endif
919 
920 /*
921 ** Constants for the largest and smallest possible 64-bit signed integers.
922 ** These macros are designed to work correctly on both 32-bit and 64-bit
923 ** compilers.
924 */
925 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
926 #define LARGEST_UINT64 (0xffffffff|(((u64)0xffffffff)<<32))
927 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
928 
929 /*
930 ** Round up a number to the next larger multiple of 8.  This is used
931 ** to force 8-byte alignment on 64-bit architectures.
932 */
933 #define ROUND8(x)     (((x)+7)&~7)
934 
935 /*
936 ** Round down to the nearest multiple of 8
937 */
938 #define ROUNDDOWN8(x) ((x)&~7)
939 
940 /*
941 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
942 ** macro is used only within assert() to verify that the code gets
943 ** all alignment restrictions correct.
944 **
945 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
946 ** underlying malloc() implementation might return us 4-byte aligned
947 ** pointers.  In that case, only verify 4-byte alignment.
948 */
949 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
950 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
951 #else
952 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
953 #endif
954 
955 /*
956 ** Disable MMAP on platforms where it is known to not work
957 */
958 #if defined(__OpenBSD__) || defined(__QNXNTO__)
959 # undef SQLITE_MAX_MMAP_SIZE
960 # define SQLITE_MAX_MMAP_SIZE 0
961 #endif
962 
963 /*
964 ** Default maximum size of memory used by memory-mapped I/O in the VFS
965 */
966 #ifdef __APPLE__
967 # include <TargetConditionals.h>
968 #endif
969 #ifndef SQLITE_MAX_MMAP_SIZE
970 # if defined(__linux__) \
971   || defined(_WIN32) \
972   || (defined(__APPLE__) && defined(__MACH__)) \
973   || defined(__sun) \
974   || defined(__FreeBSD__) \
975   || defined(__DragonFly__)
976 #   define SQLITE_MAX_MMAP_SIZE 0x7fff0000  /* 2147418112 */
977 # else
978 #   define SQLITE_MAX_MMAP_SIZE 0
979 # endif
980 #endif
981 
982 /*
983 ** The default MMAP_SIZE is zero on all platforms.  Or, even if a larger
984 ** default MMAP_SIZE is specified at compile-time, make sure that it does
985 ** not exceed the maximum mmap size.
986 */
987 #ifndef SQLITE_DEFAULT_MMAP_SIZE
988 # define SQLITE_DEFAULT_MMAP_SIZE 0
989 #endif
990 #if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
991 # undef SQLITE_DEFAULT_MMAP_SIZE
992 # define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
993 #endif
994 
995 /*
996 ** SELECTTRACE_ENABLED will be either 1 or 0 depending on whether or not
997 ** the Select query generator tracing logic is turned on.
998 */
999 #if !defined(SQLITE_AMALGAMATION)
1000 extern u32 sqlite3SelectTrace;
1001 #endif
1002 #if defined(SQLITE_DEBUG) \
1003     && (defined(SQLITE_TEST) || defined(SQLITE_ENABLE_SELECTTRACE))
1004 # define SELECTTRACE_ENABLED 1
1005 # define SELECTTRACE(K,P,S,X)  \
1006   if(sqlite3SelectTrace&(K))   \
1007     sqlite3DebugPrintf("%u/%d/%p: ",(S)->selId,(P)->addrExplain,(S)),\
1008     sqlite3DebugPrintf X
1009 #else
1010 # define SELECTTRACE(K,P,S,X)
1011 # define SELECTTRACE_ENABLED 0
1012 #endif
1013 
1014 /*
1015 ** Macros for "wheretrace"
1016 */
1017 extern u32 sqlite3WhereTrace;
1018 #if defined(SQLITE_DEBUG) \
1019     && (defined(SQLITE_TEST) || defined(SQLITE_ENABLE_WHERETRACE))
1020 # define WHERETRACE(K,X)  if(sqlite3WhereTrace&(K)) sqlite3DebugPrintf X
1021 # define WHERETRACE_ENABLED 1
1022 #else
1023 # define WHERETRACE(K,X)
1024 #endif
1025 
1026 
1027 /*
1028 ** An instance of the following structure is used to store the busy-handler
1029 ** callback for a given sqlite handle.
1030 **
1031 ** The sqlite.busyHandler member of the sqlite struct contains the busy
1032 ** callback for the database handle. Each pager opened via the sqlite
1033 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
1034 ** callback is currently invoked only from within pager.c.
1035 */
1036 typedef struct BusyHandler BusyHandler;
1037 struct BusyHandler {
1038   int (*xBusyHandler)(void *,int);  /* The busy callback */
1039   void *pBusyArg;                   /* First arg to busy callback */
1040   int nBusy;                        /* Incremented with each busy call */
1041 };
1042 
1043 /*
1044 ** Name of table that holds the database schema.
1045 */
1046 #define DFLT_SCHEMA_TABLE          "sqlite_master"
1047 #define DFLT_TEMP_SCHEMA_TABLE     "sqlite_temp_master"
1048 #define ALT_SCHEMA_TABLE           "sqlite_schema"
1049 #define ALT_TEMP_SCHEMA_TABLE      "sqlite_temp_schema"
1050 
1051 
1052 /*
1053 ** The root-page of the schema table.
1054 */
1055 #define SCHEMA_ROOT    1
1056 
1057 /*
1058 ** The name of the schema table.  The name is different for TEMP.
1059 */
1060 #define SCHEMA_TABLE(x) \
1061     ((!OMIT_TEMPDB)&&(x==1)?DFLT_TEMP_SCHEMA_TABLE:DFLT_SCHEMA_TABLE)
1062 
1063 /*
1064 ** A convenience macro that returns the number of elements in
1065 ** an array.
1066 */
1067 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
1068 
1069 /*
1070 ** Determine if the argument is a power of two
1071 */
1072 #define IsPowerOfTwo(X) (((X)&((X)-1))==0)
1073 
1074 /*
1075 ** The following value as a destructor means to use sqlite3DbFree().
1076 ** The sqlite3DbFree() routine requires two parameters instead of the
1077 ** one parameter that destructors normally want.  So we have to introduce
1078 ** this magic value that the code knows to handle differently.  Any
1079 ** pointer will work here as long as it is distinct from SQLITE_STATIC
1080 ** and SQLITE_TRANSIENT.
1081 */
1082 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3OomFault)
1083 
1084 /*
1085 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
1086 ** not support Writable Static Data (WSD) such as global and static variables.
1087 ** All variables must either be on the stack or dynamically allocated from
1088 ** the heap.  When WSD is unsupported, the variable declarations scattered
1089 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
1090 ** macro is used for this purpose.  And instead of referencing the variable
1091 ** directly, we use its constant as a key to lookup the run-time allocated
1092 ** buffer that holds real variable.  The constant is also the initializer
1093 ** for the run-time allocated buffer.
1094 **
1095 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
1096 ** macros become no-ops and have zero performance impact.
1097 */
1098 #ifdef SQLITE_OMIT_WSD
1099   #define SQLITE_WSD const
1100   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
1101   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
1102   int sqlite3_wsd_init(int N, int J);
1103   void *sqlite3_wsd_find(void *K, int L);
1104 #else
1105   #define SQLITE_WSD
1106   #define GLOBAL(t,v) v
1107   #define sqlite3GlobalConfig sqlite3Config
1108 #endif
1109 
1110 /*
1111 ** The following macros are used to suppress compiler warnings and to
1112 ** make it clear to human readers when a function parameter is deliberately
1113 ** left unused within the body of a function. This usually happens when
1114 ** a function is called via a function pointer. For example the
1115 ** implementation of an SQL aggregate step callback may not use the
1116 ** parameter indicating the number of arguments passed to the aggregate,
1117 ** if it knows that this is enforced elsewhere.
1118 **
1119 ** When a function parameter is not used at all within the body of a function,
1120 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
1121 ** However, these macros may also be used to suppress warnings related to
1122 ** parameters that may or may not be used depending on compilation options.
1123 ** For example those parameters only used in assert() statements. In these
1124 ** cases the parameters are named as per the usual conventions.
1125 */
1126 #define UNUSED_PARAMETER(x) (void)(x)
1127 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
1128 
1129 /*
1130 ** Forward references to structures
1131 */
1132 typedef struct AggInfo AggInfo;
1133 typedef struct AuthContext AuthContext;
1134 typedef struct AutoincInfo AutoincInfo;
1135 typedef struct Bitvec Bitvec;
1136 typedef struct CollSeq CollSeq;
1137 typedef struct Column Column;
1138 typedef struct Db Db;
1139 typedef struct Schema Schema;
1140 typedef struct Expr Expr;
1141 typedef struct ExprList ExprList;
1142 typedef struct FKey FKey;
1143 typedef struct FuncDestructor FuncDestructor;
1144 typedef struct FuncDef FuncDef;
1145 typedef struct FuncDefHash FuncDefHash;
1146 typedef struct IdList IdList;
1147 typedef struct Index Index;
1148 typedef struct IndexSample IndexSample;
1149 typedef struct KeyClass KeyClass;
1150 typedef struct KeyInfo KeyInfo;
1151 typedef struct Lookaside Lookaside;
1152 typedef struct LookasideSlot LookasideSlot;
1153 typedef struct Module Module;
1154 typedef struct NameContext NameContext;
1155 typedef struct Parse Parse;
1156 typedef struct PreUpdate PreUpdate;
1157 typedef struct PrintfArguments PrintfArguments;
1158 typedef struct RenameToken RenameToken;
1159 typedef struct RowSet RowSet;
1160 typedef struct Savepoint Savepoint;
1161 typedef struct Select Select;
1162 typedef struct SQLiteThread SQLiteThread;
1163 typedef struct SelectDest SelectDest;
1164 typedef struct SrcList SrcList;
1165 typedef struct sqlite3_str StrAccum; /* Internal alias for sqlite3_str */
1166 typedef struct Table Table;
1167 typedef struct TableLock TableLock;
1168 typedef struct Token Token;
1169 typedef struct TreeView TreeView;
1170 typedef struct Trigger Trigger;
1171 typedef struct TriggerPrg TriggerPrg;
1172 typedef struct TriggerStep TriggerStep;
1173 typedef struct UnpackedRecord UnpackedRecord;
1174 typedef struct Upsert Upsert;
1175 typedef struct VTable VTable;
1176 typedef struct VtabCtx VtabCtx;
1177 typedef struct Walker Walker;
1178 typedef struct WhereInfo WhereInfo;
1179 typedef struct Window Window;
1180 typedef struct With With;
1181 
1182 
1183 /*
1184 ** The bitmask datatype defined below is used for various optimizations.
1185 **
1186 ** Changing this from a 64-bit to a 32-bit type limits the number of
1187 ** tables in a join to 32 instead of 64.  But it also reduces the size
1188 ** of the library by 738 bytes on ix86.
1189 */
1190 #ifdef SQLITE_BITMASK_TYPE
1191   typedef SQLITE_BITMASK_TYPE Bitmask;
1192 #else
1193   typedef u64 Bitmask;
1194 #endif
1195 
1196 /*
1197 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
1198 */
1199 #define BMS  ((int)(sizeof(Bitmask)*8))
1200 
1201 /*
1202 ** A bit in a Bitmask
1203 */
1204 #define MASKBIT(n)   (((Bitmask)1)<<(n))
1205 #define MASKBIT64(n) (((u64)1)<<(n))
1206 #define MASKBIT32(n) (((unsigned int)1)<<(n))
1207 #define ALLBITS      ((Bitmask)-1)
1208 
1209 /* A VList object records a mapping between parameters/variables/wildcards
1210 ** in the SQL statement (such as $abc, @pqr, or :xyz) and the integer
1211 ** variable number associated with that parameter.  See the format description
1212 ** on the sqlite3VListAdd() routine for more information.  A VList is really
1213 ** just an array of integers.
1214 */
1215 typedef int VList;
1216 
1217 /*
1218 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
1219 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
1220 ** pointer types (i.e. FuncDef) defined above.
1221 */
1222 #include "pager.h"
1223 #include "btree.h"
1224 #include "vdbe.h"
1225 #include "pcache.h"
1226 #include "os.h"
1227 #include "mutex.h"
1228 
1229 /* The SQLITE_EXTRA_DURABLE compile-time option used to set the default
1230 ** synchronous setting to EXTRA.  It is no longer supported.
1231 */
1232 #ifdef SQLITE_EXTRA_DURABLE
1233 # warning Use SQLITE_DEFAULT_SYNCHRONOUS=3 instead of SQLITE_EXTRA_DURABLE
1234 # define SQLITE_DEFAULT_SYNCHRONOUS 3
1235 #endif
1236 
1237 /*
1238 ** Default synchronous levels.
1239 **
1240 ** Note that (for historcal reasons) the PAGER_SYNCHRONOUS_* macros differ
1241 ** from the SQLITE_DEFAULT_SYNCHRONOUS value by 1.
1242 **
1243 **           PAGER_SYNCHRONOUS       DEFAULT_SYNCHRONOUS
1244 **   OFF           1                         0
1245 **   NORMAL        2                         1
1246 **   FULL          3                         2
1247 **   EXTRA         4                         3
1248 **
1249 ** The "PRAGMA synchronous" statement also uses the zero-based numbers.
1250 ** In other words, the zero-based numbers are used for all external interfaces
1251 ** and the one-based values are used internally.
1252 */
1253 #ifndef SQLITE_DEFAULT_SYNCHRONOUS
1254 # define SQLITE_DEFAULT_SYNCHRONOUS 2
1255 #endif
1256 #ifndef SQLITE_DEFAULT_WAL_SYNCHRONOUS
1257 # define SQLITE_DEFAULT_WAL_SYNCHRONOUS SQLITE_DEFAULT_SYNCHRONOUS
1258 #endif
1259 
1260 /*
1261 ** Each database file to be accessed by the system is an instance
1262 ** of the following structure.  There are normally two of these structures
1263 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
1264 ** aDb[1] is the database file used to hold temporary tables.  Additional
1265 ** databases may be attached.
1266 */
1267 struct Db {
1268   char *zDbSName;      /* Name of this database. (schema name, not filename) */
1269   Btree *pBt;          /* The B*Tree structure for this database file */
1270   u8 safety_level;     /* How aggressive at syncing data to disk */
1271   u8 bSyncSet;         /* True if "PRAGMA synchronous=N" has been run */
1272   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
1273 };
1274 
1275 /*
1276 ** An instance of the following structure stores a database schema.
1277 **
1278 ** Most Schema objects are associated with a Btree.  The exception is
1279 ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
1280 ** In shared cache mode, a single Schema object can be shared by multiple
1281 ** Btrees that refer to the same underlying BtShared object.
1282 **
1283 ** Schema objects are automatically deallocated when the last Btree that
1284 ** references them is destroyed.   The TEMP Schema is manually freed by
1285 ** sqlite3_close().
1286 *
1287 ** A thread must be holding a mutex on the corresponding Btree in order
1288 ** to access Schema content.  This implies that the thread must also be
1289 ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
1290 ** For a TEMP Schema, only the connection mutex is required.
1291 */
1292 struct Schema {
1293   int schema_cookie;   /* Database schema version number for this file */
1294   int iGeneration;     /* Generation counter.  Incremented with each change */
1295   Hash tblHash;        /* All tables indexed by name */
1296   Hash idxHash;        /* All (named) indices indexed by name */
1297   Hash trigHash;       /* All triggers indexed by name */
1298   Hash fkeyHash;       /* All foreign keys by referenced table name */
1299   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
1300   u8 file_format;      /* Schema format version for this file */
1301   u8 enc;              /* Text encoding used by this database */
1302   u16 schemaFlags;     /* Flags associated with this schema */
1303   int cache_size;      /* Number of pages to use in the cache */
1304 };
1305 
1306 /*
1307 ** These macros can be used to test, set, or clear bits in the
1308 ** Db.pSchema->flags field.
1309 */
1310 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))
1311 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->schemaFlags&(P))!=0)
1312 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->schemaFlags|=(P)
1313 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->schemaFlags&=~(P)
1314 
1315 /*
1316 ** Allowed values for the DB.pSchema->flags field.
1317 **
1318 ** The DB_SchemaLoaded flag is set after the database schema has been
1319 ** read into internal hash tables.
1320 **
1321 ** DB_UnresetViews means that one or more views have column names that
1322 ** have been filled out.  If the schema changes, these column names might
1323 ** changes and so the view will need to be reset.
1324 */
1325 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
1326 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
1327 #define DB_ResetWanted     0x0008  /* Reset the schema when nSchemaLock==0 */
1328 
1329 /*
1330 ** The number of different kinds of things that can be limited
1331 ** using the sqlite3_limit() interface.
1332 */
1333 #define SQLITE_N_LIMIT (SQLITE_LIMIT_WORKER_THREADS+1)
1334 
1335 /*
1336 ** Lookaside malloc is a set of fixed-size buffers that can be used
1337 ** to satisfy small transient memory allocation requests for objects
1338 ** associated with a particular database connection.  The use of
1339 ** lookaside malloc provides a significant performance enhancement
1340 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
1341 ** SQL statements.
1342 **
1343 ** The Lookaside structure holds configuration information about the
1344 ** lookaside malloc subsystem.  Each available memory allocation in
1345 ** the lookaside subsystem is stored on a linked list of LookasideSlot
1346 ** objects.
1347 **
1348 ** Lookaside allocations are only allowed for objects that are associated
1349 ** with a particular database connection.  Hence, schema information cannot
1350 ** be stored in lookaside because in shared cache mode the schema information
1351 ** is shared by multiple database connections.  Therefore, while parsing
1352 ** schema information, the Lookaside.bEnabled flag is cleared so that
1353 ** lookaside allocations are not used to construct the schema objects.
1354 **
1355 ** New lookaside allocations are only allowed if bDisable==0.  When
1356 ** bDisable is greater than zero, sz is set to zero which effectively
1357 ** disables lookaside without adding a new test for the bDisable flag
1358 ** in a performance-critical path.  sz should be set by to szTrue whenever
1359 ** bDisable changes back to zero.
1360 **
1361 ** Lookaside buffers are initially held on the pInit list.  As they are
1362 ** used and freed, they are added back to the pFree list.  New allocations
1363 ** come off of pFree first, then pInit as a fallback.  This dual-list
1364 ** allows use to compute a high-water mark - the maximum number of allocations
1365 ** outstanding at any point in the past - by subtracting the number of
1366 ** allocations on the pInit list from the total number of allocations.
1367 **
1368 ** Enhancement on 2019-12-12:  Two-size-lookaside
1369 ** The default lookaside configuration is 100 slots of 1200 bytes each.
1370 ** The larger slot sizes are important for performance, but they waste
1371 ** a lot of space, as most lookaside allocations are less than 128 bytes.
1372 ** The two-size-lookaside enhancement breaks up the lookaside allocation
1373 ** into two pools:  One of 128-byte slots and the other of the default size
1374 ** (1200-byte) slots.   Allocations are filled from the small-pool first,
1375 ** failing over to the full-size pool if that does not work.  Thus more
1376 ** lookaside slots are available while also using less memory.
1377 ** This enhancement can be omitted by compiling with
1378 ** SQLITE_OMIT_TWOSIZE_LOOKASIDE.
1379 */
1380 struct Lookaside {
1381   u32 bDisable;           /* Only operate the lookaside when zero */
1382   u16 sz;                 /* Size of each buffer in bytes */
1383   u16 szTrue;             /* True value of sz, even if disabled */
1384   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
1385   u32 nSlot;              /* Number of lookaside slots allocated */
1386   u32 anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
1387   LookasideSlot *pInit;   /* List of buffers not previously used */
1388   LookasideSlot *pFree;   /* List of available buffers */
1389 #ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
1390   LookasideSlot *pSmallInit; /* List of small buffers not prediously used */
1391   LookasideSlot *pSmallFree; /* List of available small buffers */
1392   void *pMiddle;          /* First byte past end of full-size buffers and
1393                           ** the first byte of LOOKASIDE_SMALL buffers */
1394 #endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
1395   void *pStart;           /* First byte of available memory space */
1396   void *pEnd;             /* First byte past end of available space */
1397 };
1398 struct LookasideSlot {
1399   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
1400 };
1401 
1402 #define DisableLookaside  db->lookaside.bDisable++;db->lookaside.sz=0
1403 #define EnableLookaside   db->lookaside.bDisable--;\
1404    db->lookaside.sz=db->lookaside.bDisable?0:db->lookaside.szTrue
1405 
1406 /* Size of the smaller allocations in two-size lookside */
1407 #ifdef SQLITE_OMIT_TWOSIZE_LOOKASIDE
1408 #  define LOOKASIDE_SMALL           0
1409 #else
1410 #  define LOOKASIDE_SMALL         128
1411 #endif
1412 
1413 /*
1414 ** A hash table for built-in function definitions.  (Application-defined
1415 ** functions use a regular table table from hash.h.)
1416 **
1417 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
1418 ** Collisions are on the FuncDef.u.pHash chain.  Use the SQLITE_FUNC_HASH()
1419 ** macro to compute a hash on the function name.
1420 */
1421 #define SQLITE_FUNC_HASH_SZ 23
1422 struct FuncDefHash {
1423   FuncDef *a[SQLITE_FUNC_HASH_SZ];       /* Hash table for functions */
1424 };
1425 #define SQLITE_FUNC_HASH(C,L) (((C)+(L))%SQLITE_FUNC_HASH_SZ)
1426 
1427 #ifdef SQLITE_USER_AUTHENTICATION
1428 /*
1429 ** Information held in the "sqlite3" database connection object and used
1430 ** to manage user authentication.
1431 */
1432 typedef struct sqlite3_userauth sqlite3_userauth;
1433 struct sqlite3_userauth {
1434   u8 authLevel;                 /* Current authentication level */
1435   int nAuthPW;                  /* Size of the zAuthPW in bytes */
1436   char *zAuthPW;                /* Password used to authenticate */
1437   char *zAuthUser;              /* User name used to authenticate */
1438 };
1439 
1440 /* Allowed values for sqlite3_userauth.authLevel */
1441 #define UAUTH_Unknown     0     /* Authentication not yet checked */
1442 #define UAUTH_Fail        1     /* User authentication failed */
1443 #define UAUTH_User        2     /* Authenticated as a normal user */
1444 #define UAUTH_Admin       3     /* Authenticated as an administrator */
1445 
1446 /* Functions used only by user authorization logic */
1447 int sqlite3UserAuthTable(const char*);
1448 int sqlite3UserAuthCheckLogin(sqlite3*,const char*,u8*);
1449 void sqlite3UserAuthInit(sqlite3*);
1450 void sqlite3CryptFunc(sqlite3_context*,int,sqlite3_value**);
1451 
1452 #endif /* SQLITE_USER_AUTHENTICATION */
1453 
1454 /*
1455 ** typedef for the authorization callback function.
1456 */
1457 #ifdef SQLITE_USER_AUTHENTICATION
1458   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1459                                const char*, const char*);
1460 #else
1461   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1462                                const char*);
1463 #endif
1464 
1465 #ifndef SQLITE_OMIT_DEPRECATED
1466 /* This is an extra SQLITE_TRACE macro that indicates "legacy" tracing
1467 ** in the style of sqlite3_trace()
1468 */
1469 #define SQLITE_TRACE_LEGACY          0x40     /* Use the legacy xTrace */
1470 #define SQLITE_TRACE_XPROFILE        0x80     /* Use the legacy xProfile */
1471 #else
1472 #define SQLITE_TRACE_LEGACY          0
1473 #define SQLITE_TRACE_XPROFILE        0
1474 #endif /* SQLITE_OMIT_DEPRECATED */
1475 #define SQLITE_TRACE_NONLEGACY_MASK  0x0f     /* Normal flags */
1476 
1477 
1478 /*
1479 ** Each database connection is an instance of the following structure.
1480 */
1481 struct sqlite3 {
1482   sqlite3_vfs *pVfs;            /* OS Interface */
1483   struct Vdbe *pVdbe;           /* List of active virtual machines */
1484   CollSeq *pDfltColl;           /* BINARY collseq for the database encoding */
1485   sqlite3_mutex *mutex;         /* Connection mutex */
1486   Db *aDb;                      /* All backends */
1487   int nDb;                      /* Number of backends currently in use */
1488   u32 mDbFlags;                 /* flags recording internal state */
1489   u64 flags;                    /* flags settable by pragmas. See below */
1490   i64 lastRowid;                /* ROWID of most recent insert (see above) */
1491   i64 szMmap;                   /* Default mmap_size setting */
1492   u32 nSchemaLock;              /* Do not reset the schema when non-zero */
1493   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
1494   int errCode;                  /* Most recent error code (SQLITE_*) */
1495   int errMask;                  /* & result codes with this before returning */
1496   int iSysErrno;                /* Errno value from last system error */
1497   u16 dbOptFlags;               /* Flags to enable/disable optimizations */
1498   u8 enc;                       /* Text encoding */
1499   u8 autoCommit;                /* The auto-commit flag. */
1500   u8 temp_store;                /* 1: file 2: memory 0: default */
1501   u8 mallocFailed;              /* True if we have seen a malloc failure */
1502   u8 bBenignMalloc;             /* Do not require OOMs if true */
1503   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
1504   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
1505   u8 suppressErr;               /* Do not issue error messages if true */
1506   u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
1507   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
1508   u8 mTrace;                    /* zero or more SQLITE_TRACE flags */
1509   u8 noSharedCache;             /* True if no shared-cache backends */
1510   u8 nSqlExec;                  /* Number of pending OP_SqlExec opcodes */
1511   int nextPagesize;             /* Pagesize after VACUUM if >0 */
1512   u32 magic;                    /* Magic number for detect library misuse */
1513   int nChange;                  /* Value returned by sqlite3_changes() */
1514   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
1515   int aLimit[SQLITE_N_LIMIT];   /* Limits */
1516   int nMaxSorterMmap;           /* Maximum size of regions mapped by sorter */
1517   struct sqlite3InitInfo {      /* Information used during initialization */
1518     Pgno newTnum;               /* Rootpage of table being initialized */
1519     u8 iDb;                     /* Which db file is being initialized */
1520     u8 busy;                    /* TRUE if currently initializing */
1521     unsigned orphanTrigger : 1; /* Last statement is orphaned TEMP trigger */
1522     unsigned imposterTable : 1; /* Building an imposter table */
1523     unsigned reopenMemdb : 1;   /* ATTACH is really a reopen using MemDB */
1524     char **azInit;              /* "type", "name", and "tbl_name" columns */
1525   } init;
1526   int nVdbeActive;              /* Number of VDBEs currently running */
1527   int nVdbeRead;                /* Number of active VDBEs that read or write */
1528   int nVdbeWrite;               /* Number of active VDBEs that read and write */
1529   int nVdbeExec;                /* Number of nested calls to VdbeExec() */
1530   int nVDestroy;                /* Number of active OP_VDestroy operations */
1531   int nExtension;               /* Number of loaded extensions */
1532   void **aExtension;            /* Array of shared library handles */
1533   union {
1534     void (*xLegacy)(void*,const char*);     /* Legacy trace function */
1535     int (*xV2)(u32,void*,void*,void*);      /* V2 Trace function */
1536   } trace;
1537   void *pTraceArg;                          /* Argument to the trace function */
1538 #ifndef SQLITE_OMIT_DEPRECATED
1539   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
1540   void *pProfileArg;                        /* Argument to profile function */
1541 #endif
1542   void *pCommitArg;                 /* Argument to xCommitCallback() */
1543   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
1544   void *pRollbackArg;               /* Argument to xRollbackCallback() */
1545   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
1546   void *pUpdateArg;
1547   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
1548   Parse *pParse;                /* Current parse */
1549 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
1550   void *pPreUpdateArg;          /* First argument to xPreUpdateCallback */
1551   void (*xPreUpdateCallback)(   /* Registered using sqlite3_preupdate_hook() */
1552     void*,sqlite3*,int,char const*,char const*,sqlite3_int64,sqlite3_int64
1553   );
1554   PreUpdate *pPreUpdate;        /* Context for active pre-update callback */
1555 #endif /* SQLITE_ENABLE_PREUPDATE_HOOK */
1556 #ifndef SQLITE_OMIT_WAL
1557   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
1558   void *pWalArg;
1559 #endif
1560   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
1561   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
1562   void *pCollNeededArg;
1563   sqlite3_value *pErr;          /* Most recent error message */
1564   union {
1565     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
1566     double notUsed1;            /* Spacer */
1567   } u1;
1568   Lookaside lookaside;          /* Lookaside malloc configuration */
1569 #ifndef SQLITE_OMIT_AUTHORIZATION
1570   sqlite3_xauth xAuth;          /* Access authorization function */
1571   void *pAuthArg;               /* 1st argument to the access auth function */
1572 #endif
1573 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
1574   int (*xProgress)(void *);     /* The progress callback */
1575   void *pProgressArg;           /* Argument to the progress callback */
1576   unsigned nProgressOps;        /* Number of opcodes for progress callback */
1577 #endif
1578 #ifndef SQLITE_OMIT_VIRTUALTABLE
1579   int nVTrans;                  /* Allocated size of aVTrans */
1580   Hash aModule;                 /* populated by sqlite3_create_module() */
1581   VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
1582   VTable **aVTrans;             /* Virtual tables with open transactions */
1583   VTable *pDisconnect;          /* Disconnect these in next sqlite3_prepare() */
1584 #endif
1585   Hash aFunc;                   /* Hash table of connection functions */
1586   Hash aCollSeq;                /* All collating sequences */
1587   BusyHandler busyHandler;      /* Busy callback */
1588   Db aDbStatic[2];              /* Static space for the 2 default backends */
1589   Savepoint *pSavepoint;        /* List of active savepoints */
1590   int nAnalysisLimit;           /* Number of index rows to ANALYZE */
1591   int busyTimeout;              /* Busy handler timeout, in msec */
1592   int nSavepoint;               /* Number of non-transaction savepoints */
1593   int nStatement;               /* Number of nested statement-transactions  */
1594   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
1595   i64 nDeferredImmCons;         /* Net deferred immediate constraints */
1596   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
1597 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
1598   /* The following variables are all protected by the STATIC_MAIN
1599   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
1600   **
1601   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
1602   ** unlock so that it can proceed.
1603   **
1604   ** When X.pBlockingConnection==Y, that means that something that X tried
1605   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
1606   ** held by Y.
1607   */
1608   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
1609   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
1610   void *pUnlockArg;                     /* Argument to xUnlockNotify */
1611   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
1612   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
1613 #endif
1614 #ifdef SQLITE_USER_AUTHENTICATION
1615   sqlite3_userauth auth;        /* User authentication information */
1616 #endif
1617 };
1618 
1619 /*
1620 ** A macro to discover the encoding of a database.
1621 */
1622 #define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
1623 #define ENC(db)        ((db)->enc)
1624 
1625 /*
1626 ** A u64 constant where the lower 32 bits are all zeros.  Only the
1627 ** upper 32 bits are included in the argument.  Necessary because some
1628 ** C-compilers still do not accept LL integer literals.
1629 */
1630 #define HI(X)  ((u64)(X)<<32)
1631 
1632 /*
1633 ** Possible values for the sqlite3.flags.
1634 **
1635 ** Value constraints (enforced via assert()):
1636 **      SQLITE_FullFSync     == PAGER_FULLFSYNC
1637 **      SQLITE_CkptFullFSync == PAGER_CKPT_FULLFSYNC
1638 **      SQLITE_CacheSpill    == PAGER_CACHE_SPILL
1639 */
1640 #define SQLITE_WriteSchema    0x00000001  /* OK to update SQLITE_SCHEMA */
1641 #define SQLITE_LegacyFileFmt  0x00000002  /* Create new databases in format 1 */
1642 #define SQLITE_FullColNames   0x00000004  /* Show full column names on SELECT */
1643 #define SQLITE_FullFSync      0x00000008  /* Use full fsync on the backend */
1644 #define SQLITE_CkptFullFSync  0x00000010  /* Use full fsync for checkpoint */
1645 #define SQLITE_CacheSpill     0x00000020  /* OK to spill pager cache */
1646 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
1647 #define SQLITE_TrustedSchema  0x00000080  /* Allow unsafe functions and
1648                                           ** vtabs in the schema definition */
1649 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
1650                                           /*   result set is empty */
1651 #define SQLITE_IgnoreChecks   0x00000200  /* Do not enforce check constraints */
1652 #define SQLITE_ReadUncommit   0x00000400  /* READ UNCOMMITTED in shared-cache */
1653 #define SQLITE_NoCkptOnClose  0x00000800  /* No checkpoint on close()/DETACH */
1654 #define SQLITE_ReverseOrder   0x00001000  /* Reverse unordered SELECTs */
1655 #define SQLITE_RecTriggers    0x00002000  /* Enable recursive triggers */
1656 #define SQLITE_ForeignKeys    0x00004000  /* Enforce foreign key constraints  */
1657 #define SQLITE_AutoIndex      0x00008000  /* Enable automatic indexes */
1658 #define SQLITE_LoadExtension  0x00010000  /* Enable load_extension */
1659 #define SQLITE_LoadExtFunc    0x00020000  /* Enable load_extension() SQL func */
1660 #define SQLITE_EnableTrigger  0x00040000  /* True to enable triggers */
1661 #define SQLITE_DeferFKs       0x00080000  /* Defer all FK constraints */
1662 #define SQLITE_QueryOnly      0x00100000  /* Disable database changes */
1663 #define SQLITE_CellSizeCk     0x00200000  /* Check btree cell sizes on load */
1664 #define SQLITE_Fts3Tokenizer  0x00400000  /* Enable fts3_tokenizer(2) */
1665 #define SQLITE_EnableQPSG     0x00800000  /* Query Planner Stability Guarantee*/
1666 #define SQLITE_TriggerEQP     0x01000000  /* Show trigger EXPLAIN QUERY PLAN */
1667 #define SQLITE_ResetDatabase  0x02000000  /* Reset the database */
1668 #define SQLITE_LegacyAlter    0x04000000  /* Legacy ALTER TABLE behaviour */
1669 #define SQLITE_NoSchemaError  0x08000000  /* Do not report schema parse errors*/
1670 #define SQLITE_Defensive      0x10000000  /* Input SQL is likely hostile */
1671 #define SQLITE_DqsDDL         0x20000000  /* dbl-quoted strings allowed in DDL*/
1672 #define SQLITE_DqsDML         0x40000000  /* dbl-quoted strings allowed in DML*/
1673 #define SQLITE_EnableView     0x80000000  /* Enable the use of views */
1674 #define SQLITE_CountRows      HI(0x00001) /* Count rows changed by INSERT, */
1675                                           /*   DELETE, or UPDATE and return */
1676                                           /*   the count using a callback. */
1677 
1678 /* Flags used only if debugging */
1679 #ifdef SQLITE_DEBUG
1680 #define SQLITE_SqlTrace       HI(0x0100000) /* Debug print SQL as it executes */
1681 #define SQLITE_VdbeListing    HI(0x0200000) /* Debug listings of VDBE progs */
1682 #define SQLITE_VdbeTrace      HI(0x0400000) /* True to trace VDBE execution */
1683 #define SQLITE_VdbeAddopTrace HI(0x0800000) /* Trace sqlite3VdbeAddOp() calls */
1684 #define SQLITE_VdbeEQP        HI(0x1000000) /* Debug EXPLAIN QUERY PLAN */
1685 #define SQLITE_ParserTrace    HI(0x2000000) /* PRAGMA parser_trace=ON */
1686 #endif
1687 
1688 /*
1689 ** Allowed values for sqlite3.mDbFlags
1690 */
1691 #define DBFLAG_SchemaChange   0x0001  /* Uncommitted Hash table changes */
1692 #define DBFLAG_PreferBuiltin  0x0002  /* Preference to built-in funcs */
1693 #define DBFLAG_Vacuum         0x0004  /* Currently in a VACUUM */
1694 #define DBFLAG_VacuumInto     0x0008  /* Currently running VACUUM INTO */
1695 #define DBFLAG_SchemaKnownOk  0x0010  /* Schema is known to be valid */
1696 #define DBFLAG_InternalFunc   0x0020  /* Allow use of internal functions */
1697 #define DBFLAG_EncodingFixed  0x0040  /* No longer possible to change enc. */
1698 
1699 /*
1700 ** Bits of the sqlite3.dbOptFlags field that are used by the
1701 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
1702 ** selectively disable various optimizations.
1703 */
1704 #define SQLITE_QueryFlattener 0x0001   /* Query flattening */
1705 #define SQLITE_WindowFunc     0x0002   /* Use xInverse for window functions */
1706 #define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
1707 #define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
1708 #define SQLITE_DistinctOpt    0x0010   /* DISTINCT using indexes */
1709 #define SQLITE_CoverIdxScan   0x0020   /* Covering index scans */
1710 #define SQLITE_OrderByIdxJoin 0x0040   /* ORDER BY of joins via index */
1711 #define SQLITE_Transitive     0x0080   /* Transitive constraints */
1712 #define SQLITE_OmitNoopJoin   0x0100   /* Omit unused tables in joins */
1713 #define SQLITE_CountOfView    0x0200   /* The count-of-view optimization */
1714 #define SQLITE_CursorHints    0x0400   /* Add OP_CursorHint opcodes */
1715 #define SQLITE_Stat4          0x0800   /* Use STAT4 data */
1716    /* TH3 expects the Stat4   ^^^^^^ value to be 0x0800.  Don't change it */
1717 #define SQLITE_PushDown       0x1000   /* The push-down optimization */
1718 #define SQLITE_SimplifyJoin   0x2000   /* Convert LEFT JOIN to JOIN */
1719 #define SQLITE_SkipScan       0x4000   /* Skip-scans */
1720 #define SQLITE_PropagateConst 0x8000   /* The constant propagation opt */
1721 #define SQLITE_AllOpts        0xffff   /* All optimizations */
1722 
1723 /*
1724 ** Macros for testing whether or not optimizations are enabled or disabled.
1725 */
1726 #define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
1727 #define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
1728 
1729 /*
1730 ** Return true if it OK to factor constant expressions into the initialization
1731 ** code. The argument is a Parse object for the code generator.
1732 */
1733 #define ConstFactorOk(P) ((P)->okConstFactor)
1734 
1735 /*
1736 ** Possible values for the sqlite.magic field.
1737 ** The numbers are obtained at random and have no special meaning, other
1738 ** than being distinct from one another.
1739 */
1740 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
1741 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
1742 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
1743 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
1744 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
1745 #define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */
1746 
1747 /*
1748 ** Each SQL function is defined by an instance of the following
1749 ** structure.  For global built-in functions (ex: substr(), max(), count())
1750 ** a pointer to this structure is held in the sqlite3BuiltinFunctions object.
1751 ** For per-connection application-defined functions, a pointer to this
1752 ** structure is held in the db->aHash hash table.
1753 **
1754 ** The u.pHash field is used by the global built-ins.  The u.pDestructor
1755 ** field is used by per-connection app-def functions.
1756 */
1757 struct FuncDef {
1758   i8 nArg;             /* Number of arguments.  -1 means unlimited */
1759   u32 funcFlags;       /* Some combination of SQLITE_FUNC_* */
1760   void *pUserData;     /* User data parameter */
1761   FuncDef *pNext;      /* Next function with same name */
1762   void (*xSFunc)(sqlite3_context*,int,sqlite3_value**); /* func or agg-step */
1763   void (*xFinalize)(sqlite3_context*);                  /* Agg finalizer */
1764   void (*xValue)(sqlite3_context*);                     /* Current agg value */
1765   void (*xInverse)(sqlite3_context*,int,sqlite3_value**); /* inverse agg-step */
1766   const char *zName;   /* SQL name of the function. */
1767   union {
1768     FuncDef *pHash;      /* Next with a different name but the same hash */
1769     FuncDestructor *pDestructor;   /* Reference counted destructor function */
1770   } u;
1771 };
1772 
1773 /*
1774 ** This structure encapsulates a user-function destructor callback (as
1775 ** configured using create_function_v2()) and a reference counter. When
1776 ** create_function_v2() is called to create a function with a destructor,
1777 ** a single object of this type is allocated. FuncDestructor.nRef is set to
1778 ** the number of FuncDef objects created (either 1 or 3, depending on whether
1779 ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
1780 ** member of each of the new FuncDef objects is set to point to the allocated
1781 ** FuncDestructor.
1782 **
1783 ** Thereafter, when one of the FuncDef objects is deleted, the reference
1784 ** count on this object is decremented. When it reaches 0, the destructor
1785 ** is invoked and the FuncDestructor structure freed.
1786 */
1787 struct FuncDestructor {
1788   int nRef;
1789   void (*xDestroy)(void *);
1790   void *pUserData;
1791 };
1792 
1793 /*
1794 ** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
1795 ** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  And
1796 ** SQLITE_FUNC_CONSTANT must be the same as SQLITE_DETERMINISTIC.  There
1797 ** are assert() statements in the code to verify this.
1798 **
1799 ** Value constraints (enforced via assert()):
1800 **     SQLITE_FUNC_MINMAX    ==  NC_MinMaxAgg      == SF_MinMaxAgg
1801 **     SQLITE_FUNC_LENGTH    ==  OPFLAG_LENGTHARG
1802 **     SQLITE_FUNC_TYPEOF    ==  OPFLAG_TYPEOFARG
1803 **     SQLITE_FUNC_CONSTANT  ==  SQLITE_DETERMINISTIC from the API
1804 **     SQLITE_FUNC_DIRECT    ==  SQLITE_DIRECTONLY from the API
1805 **     SQLITE_FUNC_UNSAFE    ==  SQLITE_INNOCUOUS
1806 **     SQLITE_FUNC_ENCMASK   depends on SQLITE_UTF* macros in the API
1807 */
1808 #define SQLITE_FUNC_ENCMASK  0x0003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
1809 #define SQLITE_FUNC_LIKE     0x0004 /* Candidate for the LIKE optimization */
1810 #define SQLITE_FUNC_CASE     0x0008 /* Case-sensitive LIKE-type function */
1811 #define SQLITE_FUNC_EPHEM    0x0010 /* Ephemeral.  Delete with VDBE */
1812 #define SQLITE_FUNC_NEEDCOLL 0x0020 /* sqlite3GetFuncCollSeq() might be called*/
1813 #define SQLITE_FUNC_LENGTH   0x0040 /* Built-in length() function */
1814 #define SQLITE_FUNC_TYPEOF   0x0080 /* Built-in typeof() function */
1815 #define SQLITE_FUNC_COUNT    0x0100 /* Built-in count(*) aggregate */
1816 /*                           0x0200 -- available for reuse */
1817 #define SQLITE_FUNC_UNLIKELY 0x0400 /* Built-in unlikely() function */
1818 #define SQLITE_FUNC_CONSTANT 0x0800 /* Constant inputs give a constant output */
1819 #define SQLITE_FUNC_MINMAX   0x1000 /* True for min() and max() aggregates */
1820 #define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
1821                                     ** single query - might change over time */
1822 #define SQLITE_FUNC_TEST     0x4000 /* Built-in testing functions */
1823 #define SQLITE_FUNC_OFFSET   0x8000 /* Built-in sqlite_offset() function */
1824 #define SQLITE_FUNC_WINDOW   0x00010000 /* Built-in window-only function */
1825 #define SQLITE_FUNC_INTERNAL 0x00040000 /* For use by NestedParse() only */
1826 #define SQLITE_FUNC_DIRECT   0x00080000 /* Not for use in TRIGGERs or VIEWs */
1827 #define SQLITE_FUNC_SUBTYPE  0x00100000 /* Result likely to have sub-type */
1828 #define SQLITE_FUNC_UNSAFE   0x00200000 /* Function has side effects */
1829 #define SQLITE_FUNC_INLINE   0x00400000 /* Functions implemented in-line */
1830 
1831 /* Identifier numbers for each in-line function */
1832 #define INLINEFUNC_coalesce             0
1833 #define INLINEFUNC_implies_nonnull_row  1
1834 #define INLINEFUNC_expr_implies_expr    2
1835 #define INLINEFUNC_expr_compare         3
1836 #define INLINEFUNC_affinity             4
1837 #define INLINEFUNC_iif                  5
1838 #define INLINEFUNC_unlikely            99  /* Default case */
1839 
1840 /*
1841 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
1842 ** used to create the initializers for the FuncDef structures.
1843 **
1844 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
1845 **     Used to create a scalar function definition of a function zName
1846 **     implemented by C function xFunc that accepts nArg arguments. The
1847 **     value passed as iArg is cast to a (void*) and made available
1848 **     as the user-data (sqlite3_user_data()) for the function. If
1849 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
1850 **
1851 **   VFUNCTION(zName, nArg, iArg, bNC, xFunc)
1852 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
1853 **
1854 **   SFUNCTION(zName, nArg, iArg, bNC, xFunc)
1855 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
1856 **     adds the SQLITE_DIRECTONLY flag.
1857 **
1858 **   INLINE_FUNC(zName, nArg, iFuncId, mFlags)
1859 **     zName is the name of a function that is implemented by in-line
1860 **     byte code rather than by the usual callbacks. The iFuncId
1861 **     parameter determines the function id.  The mFlags parameter is
1862 **     optional SQLITE_FUNC_ flags for this function.
1863 **
1864 **   TEST_FUNC(zName, nArg, iFuncId, mFlags)
1865 **     zName is the name of a test-only function implemented by in-line
1866 **     byte code rather than by the usual callbacks. The iFuncId
1867 **     parameter determines the function id.  The mFlags parameter is
1868 **     optional SQLITE_FUNC_ flags for this function.
1869 **
1870 **   DFUNCTION(zName, nArg, iArg, bNC, xFunc)
1871 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
1872 **     adds the SQLITE_FUNC_SLOCHNG flag.  Used for date & time functions
1873 **     and functions like sqlite_version() that can change, but not during
1874 **     a single query.  The iArg is ignored.  The user-data is always set
1875 **     to a NULL pointer.  The bNC parameter is not used.
1876 **
1877 **   MFUNCTION(zName, nArg, xPtr, xFunc)
1878 **     For math-library functions.  xPtr is an arbitrary pointer.
1879 **
1880 **   PURE_DATE(zName, nArg, iArg, bNC, xFunc)
1881 **     Used for "pure" date/time functions, this macro is like DFUNCTION
1882 **     except that it does set the SQLITE_FUNC_CONSTANT flags.  iArg is
1883 **     ignored and the user-data for these functions is set to an
1884 **     arbitrary non-NULL pointer.  The bNC parameter is not used.
1885 **
1886 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
1887 **     Used to create an aggregate function definition implemented by
1888 **     the C functions xStep and xFinal. The first four parameters
1889 **     are interpreted in the same way as the first 4 parameters to
1890 **     FUNCTION().
1891 **
1892 **   WFUNCTION(zName, nArg, iArg, xStep, xFinal, xValue, xInverse)
1893 **     Used to create an aggregate function definition implemented by
1894 **     the C functions xStep and xFinal. The first four parameters
1895 **     are interpreted in the same way as the first 4 parameters to
1896 **     FUNCTION().
1897 **
1898 **   LIKEFUNC(zName, nArg, pArg, flags)
1899 **     Used to create a scalar function definition of a function zName
1900 **     that accepts nArg arguments and is implemented by a call to C
1901 **     function likeFunc. Argument pArg is cast to a (void *) and made
1902 **     available as the function user-data (sqlite3_user_data()). The
1903 **     FuncDef.flags variable is set to the value passed as the flags
1904 **     parameter.
1905 */
1906 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1907   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1908    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
1909 #define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1910   {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1911    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
1912 #define SFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1913   {nArg, SQLITE_UTF8|SQLITE_DIRECTONLY|SQLITE_FUNC_UNSAFE, \
1914    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
1915 #define MFUNCTION(zName, nArg, xPtr, xFunc) \
1916   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
1917    xPtr, 0, xFunc, 0, 0, 0, #zName, {0} }
1918 #define INLINE_FUNC(zName, nArg, iArg, mFlags) \
1919   {nArg, SQLITE_UTF8|SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
1920    SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
1921 #define TEST_FUNC(zName, nArg, iArg, mFlags) \
1922   {nArg, SQLITE_UTF8|SQLITE_FUNC_INTERNAL|SQLITE_FUNC_TEST| \
1923          SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
1924    SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
1925 #define DFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1926   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8, \
1927    0, 0, xFunc, 0, 0, 0, #zName, {0} }
1928 #define PURE_DATE(zName, nArg, iArg, bNC, xFunc) \
1929   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|SQLITE_FUNC_CONSTANT, \
1930    (void*)&sqlite3Config, 0, xFunc, 0, 0, 0, #zName, {0} }
1931 #define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
1932   {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
1933    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
1934 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
1935   {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1936    pArg, 0, xFunc, 0, 0, 0, #zName, }
1937 #define LIKEFUNC(zName, nArg, arg, flags) \
1938   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
1939    (void *)arg, 0, likeFunc, 0, 0, 0, #zName, {0} }
1940 #define WAGGREGATE(zName, nArg, arg, nc, xStep, xFinal, xValue, xInverse, f) \
1941   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|f, \
1942    SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,xValue,xInverse,#zName, {0}}
1943 #define INTERNAL_FUNCTION(zName, nArg, xFunc) \
1944   {nArg, SQLITE_FUNC_INTERNAL|SQLITE_UTF8|SQLITE_FUNC_CONSTANT, \
1945    0, 0, xFunc, 0, 0, 0, #zName, {0} }
1946 
1947 
1948 /*
1949 ** All current savepoints are stored in a linked list starting at
1950 ** sqlite3.pSavepoint. The first element in the list is the most recently
1951 ** opened savepoint. Savepoints are added to the list by the vdbe
1952 ** OP_Savepoint instruction.
1953 */
1954 struct Savepoint {
1955   char *zName;                        /* Savepoint name (nul-terminated) */
1956   i64 nDeferredCons;                  /* Number of deferred fk violations */
1957   i64 nDeferredImmCons;               /* Number of deferred imm fk. */
1958   Savepoint *pNext;                   /* Parent savepoint (if any) */
1959 };
1960 
1961 /*
1962 ** The following are used as the second parameter to sqlite3Savepoint(),
1963 ** and as the P1 argument to the OP_Savepoint instruction.
1964 */
1965 #define SAVEPOINT_BEGIN      0
1966 #define SAVEPOINT_RELEASE    1
1967 #define SAVEPOINT_ROLLBACK   2
1968 
1969 
1970 /*
1971 ** Each SQLite module (virtual table definition) is defined by an
1972 ** instance of the following structure, stored in the sqlite3.aModule
1973 ** hash table.
1974 */
1975 struct Module {
1976   const sqlite3_module *pModule;       /* Callback pointers */
1977   const char *zName;                   /* Name passed to create_module() */
1978   int nRefModule;                      /* Number of pointers to this object */
1979   void *pAux;                          /* pAux passed to create_module() */
1980   void (*xDestroy)(void *);            /* Module destructor function */
1981   Table *pEpoTab;                      /* Eponymous table for this module */
1982 };
1983 
1984 /*
1985 ** Information about each column of an SQL table is held in an instance
1986 ** of the Column structure, in the Table.aCol[] array.
1987 **
1988 ** Definitions:
1989 **
1990 **   "table column index"     This is the index of the column in the
1991 **                            Table.aCol[] array, and also the index of
1992 **                            the column in the original CREATE TABLE stmt.
1993 **
1994 **   "storage column index"   This is the index of the column in the
1995 **                            record BLOB generated by the OP_MakeRecord
1996 **                            opcode.  The storage column index is less than
1997 **                            or equal to the table column index.  It is
1998 **                            equal if and only if there are no VIRTUAL
1999 **                            columns to the left.
2000 */
2001 struct Column {
2002   char *zName;     /* Name of this column, \000, then the type */
2003   Expr *pDflt;     /* Default value or GENERATED ALWAYS AS value */
2004   char *zColl;     /* Collating sequence.  If NULL, use the default */
2005   u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
2006   char affinity;   /* One of the SQLITE_AFF_... values */
2007   u8 szEst;        /* Estimated size of value in this column. sizeof(INT)==1 */
2008   u8 hName;        /* Column name hash for faster lookup */
2009   u16 colFlags;    /* Boolean properties.  See COLFLAG_ defines below */
2010 };
2011 
2012 /* Allowed values for Column.colFlags:
2013 */
2014 #define COLFLAG_PRIMKEY   0x0001   /* Column is part of the primary key */
2015 #define COLFLAG_HIDDEN    0x0002   /* A hidden column in a virtual table */
2016 #define COLFLAG_HASTYPE   0x0004   /* Type name follows column name */
2017 #define COLFLAG_UNIQUE    0x0008   /* Column def contains "UNIQUE" or "PK" */
2018 #define COLFLAG_SORTERREF 0x0010   /* Use sorter-refs with this column */
2019 #define COLFLAG_VIRTUAL   0x0020   /* GENERATED ALWAYS AS ... VIRTUAL */
2020 #define COLFLAG_STORED    0x0040   /* GENERATED ALWAYS AS ... STORED */
2021 #define COLFLAG_NOTAVAIL  0x0080   /* STORED column not yet calculated */
2022 #define COLFLAG_BUSY      0x0100   /* Blocks recursion on GENERATED columns */
2023 #define COLFLAG_GENERATED 0x0060   /* Combo: _STORED, _VIRTUAL */
2024 #define COLFLAG_NOINSERT  0x0062   /* Combo: _HIDDEN, _STORED, _VIRTUAL */
2025 
2026 /*
2027 ** A "Collating Sequence" is defined by an instance of the following
2028 ** structure. Conceptually, a collating sequence consists of a name and
2029 ** a comparison routine that defines the order of that sequence.
2030 **
2031 ** If CollSeq.xCmp is NULL, it means that the
2032 ** collating sequence is undefined.  Indices built on an undefined
2033 ** collating sequence may not be read or written.
2034 */
2035 struct CollSeq {
2036   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
2037   u8 enc;               /* Text encoding handled by xCmp() */
2038   void *pUser;          /* First argument to xCmp() */
2039   int (*xCmp)(void*,int, const void*, int, const void*);
2040   void (*xDel)(void*);  /* Destructor for pUser */
2041 };
2042 
2043 /*
2044 ** A sort order can be either ASC or DESC.
2045 */
2046 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
2047 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
2048 #define SQLITE_SO_UNDEFINED -1 /* No sort order specified */
2049 
2050 /*
2051 ** Column affinity types.
2052 **
2053 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
2054 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
2055 ** the speed a little by numbering the values consecutively.
2056 **
2057 ** But rather than start with 0 or 1, we begin with 'A'.  That way,
2058 ** when multiple affinity types are concatenated into a string and
2059 ** used as the P4 operand, they will be more readable.
2060 **
2061 ** Note also that the numeric types are grouped together so that testing
2062 ** for a numeric type is a single comparison.  And the BLOB type is first.
2063 */
2064 #define SQLITE_AFF_NONE     0x40  /* '@' */
2065 #define SQLITE_AFF_BLOB     0x41  /* 'A' */
2066 #define SQLITE_AFF_TEXT     0x42  /* 'B' */
2067 #define SQLITE_AFF_NUMERIC  0x43  /* 'C' */
2068 #define SQLITE_AFF_INTEGER  0x44  /* 'D' */
2069 #define SQLITE_AFF_REAL     0x45  /* 'E' */
2070 
2071 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
2072 
2073 /*
2074 ** The SQLITE_AFF_MASK values masks off the significant bits of an
2075 ** affinity value.
2076 */
2077 #define SQLITE_AFF_MASK     0x47
2078 
2079 /*
2080 ** Additional bit values that can be ORed with an affinity without
2081 ** changing the affinity.
2082 **
2083 ** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
2084 ** It causes an assert() to fire if either operand to a comparison
2085 ** operator is NULL.  It is added to certain comparison operators to
2086 ** prove that the operands are always NOT NULL.
2087 */
2088 #define SQLITE_KEEPNULL     0x08  /* Used by vector == or <> */
2089 #define SQLITE_JUMPIFNULL   0x10  /* jumps if either operand is NULL */
2090 #define SQLITE_STOREP2      0x20  /* Store result in reg[P2] rather than jump */
2091 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
2092 #define SQLITE_NOTNULL      0x90  /* Assert that operands are never NULL */
2093 
2094 /*
2095 ** An object of this type is created for each virtual table present in
2096 ** the database schema.
2097 **
2098 ** If the database schema is shared, then there is one instance of this
2099 ** structure for each database connection (sqlite3*) that uses the shared
2100 ** schema. This is because each database connection requires its own unique
2101 ** instance of the sqlite3_vtab* handle used to access the virtual table
2102 ** implementation. sqlite3_vtab* handles can not be shared between
2103 ** database connections, even when the rest of the in-memory database
2104 ** schema is shared, as the implementation often stores the database
2105 ** connection handle passed to it via the xConnect() or xCreate() method
2106 ** during initialization internally. This database connection handle may
2107 ** then be used by the virtual table implementation to access real tables
2108 ** within the database. So that they appear as part of the callers
2109 ** transaction, these accesses need to be made via the same database
2110 ** connection as that used to execute SQL operations on the virtual table.
2111 **
2112 ** All VTable objects that correspond to a single table in a shared
2113 ** database schema are initially stored in a linked-list pointed to by
2114 ** the Table.pVTable member variable of the corresponding Table object.
2115 ** When an sqlite3_prepare() operation is required to access the virtual
2116 ** table, it searches the list for the VTable that corresponds to the
2117 ** database connection doing the preparing so as to use the correct
2118 ** sqlite3_vtab* handle in the compiled query.
2119 **
2120 ** When an in-memory Table object is deleted (for example when the
2121 ** schema is being reloaded for some reason), the VTable objects are not
2122 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
2123 ** immediately. Instead, they are moved from the Table.pVTable list to
2124 ** another linked list headed by the sqlite3.pDisconnect member of the
2125 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
2126 ** next time a statement is prepared using said sqlite3*. This is done
2127 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
2128 ** Refer to comments above function sqlite3VtabUnlockList() for an
2129 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
2130 ** list without holding the corresponding sqlite3.mutex mutex.
2131 **
2132 ** The memory for objects of this type is always allocated by
2133 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
2134 ** the first argument.
2135 */
2136 struct VTable {
2137   sqlite3 *db;              /* Database connection associated with this table */
2138   Module *pMod;             /* Pointer to module implementation */
2139   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
2140   int nRef;                 /* Number of pointers to this structure */
2141   u8 bConstraint;           /* True if constraints are supported */
2142   u8 eVtabRisk;             /* Riskiness of allowing hacker access */
2143   int iSavepoint;           /* Depth of the SAVEPOINT stack */
2144   VTable *pNext;            /* Next in linked list (see above) */
2145 };
2146 
2147 /* Allowed values for VTable.eVtabRisk
2148 */
2149 #define SQLITE_VTABRISK_Low          0
2150 #define SQLITE_VTABRISK_Normal       1
2151 #define SQLITE_VTABRISK_High         2
2152 
2153 /*
2154 ** The schema for each SQL table and view is represented in memory
2155 ** by an instance of the following structure.
2156 */
2157 struct Table {
2158   char *zName;         /* Name of the table or view */
2159   Column *aCol;        /* Information about each column */
2160   Index *pIndex;       /* List of SQL indexes on this table. */
2161   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
2162   FKey *pFKey;         /* Linked list of all foreign keys in this table */
2163   char *zColAff;       /* String defining the affinity of each column */
2164   ExprList *pCheck;    /* All CHECK constraints */
2165                        /*   ... also used as column name list in a VIEW */
2166   Pgno tnum;           /* Root BTree page for this table */
2167   u32 nTabRef;         /* Number of pointers to this Table */
2168   u32 tabFlags;        /* Mask of TF_* values */
2169   i16 iPKey;           /* If not negative, use aCol[iPKey] as the rowid */
2170   i16 nCol;            /* Number of columns in this table */
2171   i16 nNVCol;          /* Number of columns that are not VIRTUAL */
2172   LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
2173   LogEst szTabRow;     /* Estimated size of each table row in bytes */
2174 #ifdef SQLITE_ENABLE_COSTMULT
2175   LogEst costMult;     /* Cost multiplier for using this table */
2176 #endif
2177   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
2178 #ifndef SQLITE_OMIT_ALTERTABLE
2179   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
2180 #endif
2181 #ifndef SQLITE_OMIT_VIRTUALTABLE
2182   int nModuleArg;      /* Number of arguments to the module */
2183   char **azModuleArg;  /* 0: module 1: schema 2: vtab name 3...: args */
2184   VTable *pVTable;     /* List of VTable objects. */
2185 #endif
2186   Trigger *pTrigger;   /* List of triggers stored in pSchema */
2187   Schema *pSchema;     /* Schema that contains this table */
2188   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
2189 };
2190 
2191 /*
2192 ** Allowed values for Table.tabFlags.
2193 **
2194 ** TF_OOOHidden applies to tables or view that have hidden columns that are
2195 ** followed by non-hidden columns.  Example:  "CREATE VIRTUAL TABLE x USING
2196 ** vtab1(a HIDDEN, b);".  Since "b" is a non-hidden column but "a" is hidden,
2197 ** the TF_OOOHidden attribute would apply in this case.  Such tables require
2198 ** special handling during INSERT processing. The "OOO" means "Out Of Order".
2199 **
2200 ** Constraints:
2201 **
2202 **         TF_HasVirtual == COLFLAG_Virtual
2203 **         TF_HasStored  == COLFLAG_Stored
2204 */
2205 #define TF_Readonly        0x0001    /* Read-only system table */
2206 #define TF_Ephemeral       0x0002    /* An ephemeral table */
2207 #define TF_HasPrimaryKey   0x0004    /* Table has a primary key */
2208 #define TF_Autoincrement   0x0008    /* Integer primary key is autoincrement */
2209 #define TF_HasStat1        0x0010    /* nRowLogEst set from sqlite_stat1 */
2210 #define TF_HasVirtual      0x0020    /* Has one or more VIRTUAL columns */
2211 #define TF_HasStored       0x0040    /* Has one or more STORED columns */
2212 #define TF_HasGenerated    0x0060    /* Combo: HasVirtual + HasStored */
2213 #define TF_WithoutRowid    0x0080    /* No rowid.  PRIMARY KEY is the key */
2214 #define TF_StatsUsed       0x0100    /* Query planner decisions affected by
2215                                      ** Index.aiRowLogEst[] values */
2216 #define TF_NoVisibleRowid  0x0200    /* No user-visible "rowid" column */
2217 #define TF_OOOHidden       0x0400    /* Out-of-Order hidden columns */
2218 #define TF_HasNotNull      0x0800    /* Contains NOT NULL constraints */
2219 #define TF_Shadow          0x1000    /* True for a shadow table */
2220 #define TF_HasStat4        0x2000    /* STAT4 info available for this table */
2221 
2222 /*
2223 ** Test to see whether or not a table is a virtual table.  This is
2224 ** done as a macro so that it will be optimized out when virtual
2225 ** table support is omitted from the build.
2226 */
2227 #ifndef SQLITE_OMIT_VIRTUALTABLE
2228 #  define IsVirtual(X)      ((X)->nModuleArg)
2229 #  define ExprIsVtab(X)  \
2230               ((X)->op==TK_COLUMN && (X)->y.pTab!=0 && (X)->y.pTab->nModuleArg)
2231 #else
2232 #  define IsVirtual(X)      0
2233 #  define ExprIsVtab(X)     0
2234 #endif
2235 
2236 /*
2237 ** Macros to determine if a column is hidden.  IsOrdinaryHiddenColumn()
2238 ** only works for non-virtual tables (ordinary tables and views) and is
2239 ** always false unless SQLITE_ENABLE_HIDDEN_COLUMNS is defined.  The
2240 ** IsHiddenColumn() macro is general purpose.
2241 */
2242 #if defined(SQLITE_ENABLE_HIDDEN_COLUMNS)
2243 #  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
2244 #  define IsOrdinaryHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
2245 #elif !defined(SQLITE_OMIT_VIRTUALTABLE)
2246 #  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
2247 #  define IsOrdinaryHiddenColumn(X) 0
2248 #else
2249 #  define IsHiddenColumn(X)         0
2250 #  define IsOrdinaryHiddenColumn(X) 0
2251 #endif
2252 
2253 
2254 /* Does the table have a rowid */
2255 #define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
2256 #define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)
2257 
2258 /*
2259 ** Each foreign key constraint is an instance of the following structure.
2260 **
2261 ** A foreign key is associated with two tables.  The "from" table is
2262 ** the table that contains the REFERENCES clause that creates the foreign
2263 ** key.  The "to" table is the table that is named in the REFERENCES clause.
2264 ** Consider this example:
2265 **
2266 **     CREATE TABLE ex1(
2267 **       a INTEGER PRIMARY KEY,
2268 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
2269 **     );
2270 **
2271 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
2272 ** Equivalent names:
2273 **
2274 **     from-table == child-table
2275 **       to-table == parent-table
2276 **
2277 ** Each REFERENCES clause generates an instance of the following structure
2278 ** which is attached to the from-table.  The to-table need not exist when
2279 ** the from-table is created.  The existence of the to-table is not checked.
2280 **
2281 ** The list of all parents for child Table X is held at X.pFKey.
2282 **
2283 ** A list of all children for a table named Z (which might not even exist)
2284 ** is held in Schema.fkeyHash with a hash key of Z.
2285 */
2286 struct FKey {
2287   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
2288   FKey *pNextFrom;  /* Next FKey with the same in pFrom. Next parent of pFrom */
2289   char *zTo;        /* Name of table that the key points to (aka: Parent) */
2290   FKey *pNextTo;    /* Next with the same zTo. Next child of zTo. */
2291   FKey *pPrevTo;    /* Previous with the same zTo */
2292   int nCol;         /* Number of columns in this key */
2293   /* EV: R-30323-21917 */
2294   u8 isDeferred;       /* True if constraint checking is deferred till COMMIT */
2295   u8 aAction[2];        /* ON DELETE and ON UPDATE actions, respectively */
2296   Trigger *apTrigger[2];/* Triggers for aAction[] actions */
2297   struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
2298     int iFrom;            /* Index of column in pFrom */
2299     char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
2300   } aCol[1];            /* One entry for each of nCol columns */
2301 };
2302 
2303 /*
2304 ** SQLite supports many different ways to resolve a constraint
2305 ** error.  ROLLBACK processing means that a constraint violation
2306 ** causes the operation in process to fail and for the current transaction
2307 ** to be rolled back.  ABORT processing means the operation in process
2308 ** fails and any prior changes from that one operation are backed out,
2309 ** but the transaction is not rolled back.  FAIL processing means that
2310 ** the operation in progress stops and returns an error code.  But prior
2311 ** changes due to the same operation are not backed out and no rollback
2312 ** occurs.  IGNORE means that the particular row that caused the constraint
2313 ** error is not inserted or updated.  Processing continues and no error
2314 ** is returned.  REPLACE means that preexisting database rows that caused
2315 ** a UNIQUE constraint violation are removed so that the new insert or
2316 ** update can proceed.  Processing continues and no error is reported.
2317 ** UPDATE applies to insert operations only and means that the insert
2318 ** is omitted and the DO UPDATE clause of an upsert is run instead.
2319 **
2320 ** RESTRICT, SETNULL, SETDFLT, and CASCADE actions apply only to foreign keys.
2321 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
2322 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
2323 ** key is set to NULL.  SETDFLT means that the foreign key is set
2324 ** to its default value.  CASCADE means that a DELETE or UPDATE of the
2325 ** referenced table row is propagated into the row that holds the
2326 ** foreign key.
2327 **
2328 ** The OE_Default value is a place holder that means to use whatever
2329 ** conflict resolution algorthm is required from context.
2330 **
2331 ** The following symbolic values are used to record which type
2332 ** of conflict resolution action to take.
2333 */
2334 #define OE_None     0   /* There is no constraint to check */
2335 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
2336 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
2337 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
2338 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
2339 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
2340 #define OE_Update   6   /* Process as a DO UPDATE in an upsert */
2341 #define OE_Restrict 7   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
2342 #define OE_SetNull  8   /* Set the foreign key value to NULL */
2343 #define OE_SetDflt  9   /* Set the foreign key value to its default */
2344 #define OE_Cascade  10  /* Cascade the changes */
2345 #define OE_Default  11  /* Do whatever the default action is */
2346 
2347 
2348 /*
2349 ** An instance of the following structure is passed as the first
2350 ** argument to sqlite3VdbeKeyCompare and is used to control the
2351 ** comparison of the two index keys.
2352 **
2353 ** Note that aSortOrder[] and aColl[] have nField+1 slots.  There
2354 ** are nField slots for the columns of an index then one extra slot
2355 ** for the rowid at the end.
2356 */
2357 struct KeyInfo {
2358   u32 nRef;           /* Number of references to this KeyInfo object */
2359   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
2360   u16 nKeyField;      /* Number of key columns in the index */
2361   u16 nAllField;      /* Total columns, including key plus others */
2362   sqlite3 *db;        /* The database connection */
2363   u8 *aSortFlags;     /* Sort order for each column. */
2364   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
2365 };
2366 
2367 /*
2368 ** Allowed bit values for entries in the KeyInfo.aSortFlags[] array.
2369 */
2370 #define KEYINFO_ORDER_DESC    0x01    /* DESC sort order */
2371 #define KEYINFO_ORDER_BIGNULL 0x02    /* NULL is larger than any other value */
2372 
2373 /*
2374 ** This object holds a record which has been parsed out into individual
2375 ** fields, for the purposes of doing a comparison.
2376 **
2377 ** A record is an object that contains one or more fields of data.
2378 ** Records are used to store the content of a table row and to store
2379 ** the key of an index.  A blob encoding of a record is created by
2380 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
2381 ** OP_Column opcode.
2382 **
2383 ** An instance of this object serves as a "key" for doing a search on
2384 ** an index b+tree. The goal of the search is to find the entry that
2385 ** is closed to the key described by this object.  This object might hold
2386 ** just a prefix of the key.  The number of fields is given by
2387 ** pKeyInfo->nField.
2388 **
2389 ** The r1 and r2 fields are the values to return if this key is less than
2390 ** or greater than a key in the btree, respectively.  These are normally
2391 ** -1 and +1 respectively, but might be inverted to +1 and -1 if the b-tree
2392 ** is in DESC order.
2393 **
2394 ** The key comparison functions actually return default_rc when they find
2395 ** an equals comparison.  default_rc can be -1, 0, or +1.  If there are
2396 ** multiple entries in the b-tree with the same key (when only looking
2397 ** at the first pKeyInfo->nFields,) then default_rc can be set to -1 to
2398 ** cause the search to find the last match, or +1 to cause the search to
2399 ** find the first match.
2400 **
2401 ** The key comparison functions will set eqSeen to true if they ever
2402 ** get and equal results when comparing this structure to a b-tree record.
2403 ** When default_rc!=0, the search might end up on the record immediately
2404 ** before the first match or immediately after the last match.  The
2405 ** eqSeen field will indicate whether or not an exact match exists in the
2406 ** b-tree.
2407 */
2408 struct UnpackedRecord {
2409   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
2410   Mem *aMem;          /* Values */
2411   u16 nField;         /* Number of entries in apMem[] */
2412   i8 default_rc;      /* Comparison result if keys are equal */
2413   u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
2414   i8 r1;              /* Value to return if (lhs < rhs) */
2415   i8 r2;              /* Value to return if (lhs > rhs) */
2416   u8 eqSeen;          /* True if an equality comparison has been seen */
2417 };
2418 
2419 
2420 /*
2421 ** Each SQL index is represented in memory by an
2422 ** instance of the following structure.
2423 **
2424 ** The columns of the table that are to be indexed are described
2425 ** by the aiColumn[] field of this structure.  For example, suppose
2426 ** we have the following table and index:
2427 **
2428 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
2429 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
2430 **
2431 ** In the Table structure describing Ex1, nCol==3 because there are
2432 ** three columns in the table.  In the Index structure describing
2433 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
2434 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
2435 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
2436 ** The second column to be indexed (c1) has an index of 0 in
2437 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
2438 **
2439 ** The Index.onError field determines whether or not the indexed columns
2440 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
2441 ** it means this is not a unique index.  Otherwise it is a unique index
2442 ** and the value of Index.onError indicate the which conflict resolution
2443 ** algorithm to employ whenever an attempt is made to insert a non-unique
2444 ** element.
2445 **
2446 ** While parsing a CREATE TABLE or CREATE INDEX statement in order to
2447 ** generate VDBE code (as opposed to parsing one read from an sqlite_schema
2448 ** table as part of parsing an existing database schema), transient instances
2449 ** of this structure may be created. In this case the Index.tnum variable is
2450 ** used to store the address of a VDBE instruction, not a database page
2451 ** number (it cannot - the database page is not allocated until the VDBE
2452 ** program is executed). See convertToWithoutRowidTable() for details.
2453 */
2454 struct Index {
2455   char *zName;             /* Name of this index */
2456   i16 *aiColumn;           /* Which columns are used by this index.  1st is 0 */
2457   LogEst *aiRowLogEst;     /* From ANALYZE: Est. rows selected by each column */
2458   Table *pTable;           /* The SQL table being indexed */
2459   char *zColAff;           /* String defining the affinity of each column */
2460   Index *pNext;            /* The next index associated with the same table */
2461   Schema *pSchema;         /* Schema containing this index */
2462   u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
2463   const char **azColl;     /* Array of collation sequence names for index */
2464   Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
2465   ExprList *aColExpr;      /* Column expressions */
2466   Pgno tnum;               /* DB Page containing root of this index */
2467   LogEst szIdxRow;         /* Estimated average row size in bytes */
2468   u16 nKeyCol;             /* Number of columns forming the key */
2469   u16 nColumn;             /* Number of columns stored in the index */
2470   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
2471   unsigned idxType:2;      /* 0:Normal 1:UNIQUE, 2:PRIMARY KEY, 3:IPK */
2472   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
2473   unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
2474   unsigned isResized:1;    /* True if resizeIndexObject() has been called */
2475   unsigned isCovering:1;   /* True if this is a covering index */
2476   unsigned noSkipScan:1;   /* Do not try to use skip-scan if true */
2477   unsigned hasStat1:1;     /* aiRowLogEst values come from sqlite_stat1 */
2478   unsigned bNoQuery:1;     /* Do not use this index to optimize queries */
2479   unsigned bAscKeyBug:1;   /* True if the bba7b69f9849b5bf bug applies */
2480   unsigned bHasVCol:1;     /* Index references one or more VIRTUAL columns */
2481 #ifdef SQLITE_ENABLE_STAT4
2482   int nSample;             /* Number of elements in aSample[] */
2483   int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
2484   tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
2485   IndexSample *aSample;    /* Samples of the left-most key */
2486   tRowcnt *aiRowEst;       /* Non-logarithmic stat1 data for this index */
2487   tRowcnt nRowEst0;        /* Non-logarithmic number of rows in the index */
2488 #endif
2489   Bitmask colNotIdxed;     /* 0 for unindexed columns in pTab */
2490 };
2491 
2492 /*
2493 ** Allowed values for Index.idxType
2494 */
2495 #define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
2496 #define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */
2497 #define SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */
2498 #define SQLITE_IDXTYPE_IPK         3   /* INTEGER PRIMARY KEY index */
2499 
2500 /* Return true if index X is a PRIMARY KEY index */
2501 #define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
2502 
2503 /* Return true if index X is a UNIQUE index */
2504 #define IsUniqueIndex(X)      ((X)->onError!=OE_None)
2505 
2506 /* The Index.aiColumn[] values are normally positive integer.  But
2507 ** there are some negative values that have special meaning:
2508 */
2509 #define XN_ROWID     (-1)     /* Indexed column is the rowid */
2510 #define XN_EXPR      (-2)     /* Indexed column is an expression */
2511 
2512 /*
2513 ** Each sample stored in the sqlite_stat4 table is represented in memory
2514 ** using a structure of this type.  See documentation at the top of the
2515 ** analyze.c source file for additional information.
2516 */
2517 struct IndexSample {
2518   void *p;          /* Pointer to sampled record */
2519   int n;            /* Size of record in bytes */
2520   tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
2521   tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
2522   tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
2523 };
2524 
2525 /*
2526 ** Possible values to use within the flags argument to sqlite3GetToken().
2527 */
2528 #define SQLITE_TOKEN_QUOTED    0x1 /* Token is a quoted identifier. */
2529 #define SQLITE_TOKEN_KEYWORD   0x2 /* Token is a keyword. */
2530 
2531 /*
2532 ** Each token coming out of the lexer is an instance of
2533 ** this structure.  Tokens are also used as part of an expression.
2534 **
2535 ** The memory that "z" points to is owned by other objects.  Take care
2536 ** that the owner of the "z" string does not deallocate the string before
2537 ** the Token goes out of scope!  Very often, the "z" points to some place
2538 ** in the middle of the Parse.zSql text.  But it might also point to a
2539 ** static string.
2540 */
2541 struct Token {
2542   const char *z;     /* Text of the token.  Not NULL-terminated! */
2543   unsigned int n;    /* Number of characters in this token */
2544 };
2545 
2546 /*
2547 ** An instance of this structure contains information needed to generate
2548 ** code for a SELECT that contains aggregate functions.
2549 **
2550 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
2551 ** pointer to this structure.  The Expr.iAgg field is the index in
2552 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
2553 ** code for that node.
2554 **
2555 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
2556 ** original Select structure that describes the SELECT statement.  These
2557 ** fields do not need to be freed when deallocating the AggInfo structure.
2558 */
2559 struct AggInfo {
2560   u8 directMode;          /* Direct rendering mode means take data directly
2561                           ** from source tables rather than from accumulators */
2562   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
2563                           ** than the source table */
2564   int sortingIdx;         /* Cursor number of the sorting index */
2565   int sortingIdxPTab;     /* Cursor number of pseudo-table */
2566   int nSortingColumn;     /* Number of columns in the sorting index */
2567   int mnReg, mxReg;       /* Range of registers allocated for aCol and aFunc */
2568   ExprList *pGroupBy;     /* The group by clause */
2569   struct AggInfo_col {    /* For each column used in source tables */
2570     Table *pTab;             /* Source table */
2571     Expr *pCExpr;            /* The original expression */
2572     int iTable;              /* Cursor number of the source table */
2573     int iMem;                /* Memory location that acts as accumulator */
2574     i16 iColumn;             /* Column number within the source table */
2575     i16 iSorterColumn;       /* Column number in the sorting index */
2576   } *aCol;
2577   int nColumn;            /* Number of used entries in aCol[] */
2578   int nAccumulator;       /* Number of columns that show through to the output.
2579                           ** Additional columns are used only as parameters to
2580                           ** aggregate functions */
2581   struct AggInfo_func {   /* For each aggregate function */
2582     Expr *pFExpr;            /* Expression encoding the function */
2583     FuncDef *pFunc;          /* The aggregate function implementation */
2584     int iMem;                /* Memory location that acts as accumulator */
2585     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
2586   } *aFunc;
2587   int nFunc;              /* Number of entries in aFunc[] */
2588   u32 selId;              /* Select to which this AggInfo belongs */
2589   AggInfo *pNext;         /* Next in list of them all */
2590 };
2591 
2592 /*
2593 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
2594 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
2595 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
2596 ** it uses less memory in the Expr object, which is a big memory user
2597 ** in systems with lots of prepared statements.  And few applications
2598 ** need more than about 10 or 20 variables.  But some extreme users want
2599 ** to have prepared statements with over 32766 variables, and for them
2600 ** the option is available (at compile-time).
2601 */
2602 #if SQLITE_MAX_VARIABLE_NUMBER<32767
2603 typedef i16 ynVar;
2604 #else
2605 typedef int ynVar;
2606 #endif
2607 
2608 /*
2609 ** Each node of an expression in the parse tree is an instance
2610 ** of this structure.
2611 **
2612 ** Expr.op is the opcode. The integer parser token codes are reused
2613 ** as opcodes here. For example, the parser defines TK_GE to be an integer
2614 ** code representing the ">=" operator. This same integer code is reused
2615 ** to represent the greater-than-or-equal-to operator in the expression
2616 ** tree.
2617 **
2618 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
2619 ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
2620 ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
2621 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
2622 ** then Expr.token contains the name of the function.
2623 **
2624 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
2625 ** binary operator. Either or both may be NULL.
2626 **
2627 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
2628 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
2629 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
2630 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
2631 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
2632 ** valid.
2633 **
2634 ** An expression of the form ID or ID.ID refers to a column in a table.
2635 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
2636 ** the integer cursor number of a VDBE cursor pointing to that table and
2637 ** Expr.iColumn is the column number for the specific column.  If the
2638 ** expression is used as a result in an aggregate SELECT, then the
2639 ** value is also stored in the Expr.iAgg column in the aggregate so that
2640 ** it can be accessed after all aggregates are computed.
2641 **
2642 ** If the expression is an unbound variable marker (a question mark
2643 ** character '?' in the original SQL) then the Expr.iTable holds the index
2644 ** number for that variable.
2645 **
2646 ** If the expression is a subquery then Expr.iColumn holds an integer
2647 ** register number containing the result of the subquery.  If the
2648 ** subquery gives a constant result, then iTable is -1.  If the subquery
2649 ** gives a different answer at different times during statement processing
2650 ** then iTable is the address of a subroutine that computes the subquery.
2651 **
2652 ** If the Expr is of type OP_Column, and the table it is selecting from
2653 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
2654 ** corresponding table definition.
2655 **
2656 ** ALLOCATION NOTES:
2657 **
2658 ** Expr objects can use a lot of memory space in database schema.  To
2659 ** help reduce memory requirements, sometimes an Expr object will be
2660 ** truncated.  And to reduce the number of memory allocations, sometimes
2661 ** two or more Expr objects will be stored in a single memory allocation,
2662 ** together with Expr.zToken strings.
2663 **
2664 ** If the EP_Reduced and EP_TokenOnly flags are set when
2665 ** an Expr object is truncated.  When EP_Reduced is set, then all
2666 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
2667 ** are contained within the same memory allocation.  Note, however, that
2668 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
2669 ** allocated, regardless of whether or not EP_Reduced is set.
2670 */
2671 struct Expr {
2672   u8 op;                 /* Operation performed by this node */
2673   char affExpr;          /* affinity, or RAISE type */
2674   u8 op2;                /* TK_REGISTER/TK_TRUTH: original value of Expr.op
2675                          ** TK_COLUMN: the value of p5 for OP_Column
2676                          ** TK_AGG_FUNCTION: nesting depth
2677                          ** TK_FUNCTION: NC_SelfRef flag if needs OP_PureFunc */
2678 #ifdef SQLITE_DEBUG
2679   u8 vvaFlags;           /* Verification flags. */
2680 #endif
2681   u32 flags;             /* Various flags.  EP_* See below */
2682   union {
2683     char *zToken;          /* Token value. Zero terminated and dequoted */
2684     int iValue;            /* Non-negative integer value if EP_IntValue */
2685   } u;
2686 
2687   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
2688   ** space is allocated for the fields below this point. An attempt to
2689   ** access them will result in a segfault or malfunction.
2690   *********************************************************************/
2691 
2692   Expr *pLeft;           /* Left subnode */
2693   Expr *pRight;          /* Right subnode */
2694   union {
2695     ExprList *pList;     /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
2696     Select *pSelect;     /* EP_xIsSelect and op = IN, EXISTS, SELECT */
2697   } x;
2698 
2699   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
2700   ** space is allocated for the fields below this point. An attempt to
2701   ** access them will result in a segfault or malfunction.
2702   *********************************************************************/
2703 
2704 #if SQLITE_MAX_EXPR_DEPTH>0
2705   int nHeight;           /* Height of the tree headed by this node */
2706 #endif
2707   int iTable;            /* TK_COLUMN: cursor number of table holding column
2708                          ** TK_REGISTER: register number
2709                          ** TK_TRIGGER: 1 -> new, 0 -> old
2710                          ** EP_Unlikely:  134217728 times likelihood
2711                          ** TK_IN: ephemerial table holding RHS
2712                          ** TK_SELECT_COLUMN: Number of columns on the LHS
2713                          ** TK_SELECT: 1st register of result vector */
2714   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
2715                          ** TK_VARIABLE: variable number (always >= 1).
2716                          ** TK_SELECT_COLUMN: column of the result vector */
2717   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
2718   int iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
2719   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
2720   union {
2721     Table *pTab;           /* TK_COLUMN: Table containing column. Can be NULL
2722                            ** for a column of an index on an expression */
2723     Window *pWin;          /* EP_WinFunc: Window/Filter defn for a function */
2724     struct {               /* TK_IN, TK_SELECT, and TK_EXISTS */
2725       int iAddr;             /* Subroutine entry address */
2726       int regReturn;         /* Register used to hold return address */
2727     } sub;
2728   } y;
2729 };
2730 
2731 /*
2732 ** The following are the meanings of bits in the Expr.flags field.
2733 ** Value restrictions:
2734 **
2735 **          EP_Agg == NC_HasAgg == SF_HasAgg
2736 **          EP_Win == NC_HasWin
2737 */
2738 #define EP_FromJoin   0x000001 /* Originates in ON/USING clause of outer join */
2739 #define EP_Distinct   0x000002 /* Aggregate function with DISTINCT keyword */
2740 #define EP_HasFunc    0x000004 /* Contains one or more functions of any kind */
2741 #define EP_FixedCol   0x000008 /* TK_Column with a known fixed value */
2742 #define EP_Agg        0x000010 /* Contains one or more aggregate functions */
2743 #define EP_VarSelect  0x000020 /* pSelect is correlated, not constant */
2744 #define EP_DblQuoted  0x000040 /* token.z was originally in "..." */
2745 #define EP_InfixFunc  0x000080 /* True for an infix function: LIKE, GLOB, etc */
2746 #define EP_Collate    0x000100 /* Tree contains a TK_COLLATE operator */
2747 #define EP_Commuted   0x000200 /* Comparison operator has been commuted */
2748 #define EP_IntValue   0x000400 /* Integer value contained in u.iValue */
2749 #define EP_xIsSelect  0x000800 /* x.pSelect is valid (otherwise x.pList is) */
2750 #define EP_Skip       0x001000 /* Operator does not contribute to affinity */
2751 #define EP_Reduced    0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
2752 #define EP_TokenOnly  0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
2753 #define EP_Win        0x008000 /* Contains window functions */
2754 #define EP_MemToken   0x010000 /* Need to sqlite3DbFree() Expr.zToken */
2755 #define EP_IfNullRow  0x020000 /* The TK_IF_NULL_ROW opcode */
2756 #define EP_Unlikely   0x040000 /* unlikely() or likelihood() function */
2757 #define EP_ConstFunc  0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
2758 #define EP_CanBeNull  0x100000 /* Can be null despite NOT NULL constraint */
2759 #define EP_Subquery   0x200000 /* Tree contains a TK_SELECT operator */
2760 #define EP_Alias      0x400000 /* Is an alias for a result set column */
2761 #define EP_Leaf       0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
2762 #define EP_WinFunc   0x1000000 /* TK_FUNCTION with Expr.y.pWin set */
2763 #define EP_Subrtn    0x2000000 /* Uses Expr.y.sub. TK_IN, _SELECT, or _EXISTS */
2764 #define EP_Quoted    0x4000000 /* TK_ID was originally quoted */
2765 #define EP_Static    0x8000000 /* Held in memory not obtained from malloc() */
2766 #define EP_IsTrue   0x10000000 /* Always has boolean value of TRUE */
2767 #define EP_IsFalse  0x20000000 /* Always has boolean value of FALSE */
2768 #define EP_FromDDL  0x40000000 /* Originates from sqlite_schema */
2769                /*   0x80000000 // Available */
2770 
2771 /*
2772 ** The EP_Propagate mask is a set of properties that automatically propagate
2773 ** upwards into parent nodes.
2774 */
2775 #define EP_Propagate (EP_Collate|EP_Subquery|EP_HasFunc)
2776 
2777 /*
2778 ** These macros can be used to test, set, or clear bits in the
2779 ** Expr.flags field.
2780 */
2781 #define ExprHasProperty(E,P)     (((E)->flags&(P))!=0)
2782 #define ExprHasAllProperty(E,P)  (((E)->flags&(P))==(P))
2783 #define ExprSetProperty(E,P)     (E)->flags|=(P)
2784 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
2785 #define ExprAlwaysTrue(E)   (((E)->flags&(EP_FromJoin|EP_IsTrue))==EP_IsTrue)
2786 #define ExprAlwaysFalse(E)  (((E)->flags&(EP_FromJoin|EP_IsFalse))==EP_IsFalse)
2787 
2788 
2789 /* Flags for use with Expr.vvaFlags
2790 */
2791 #define EP_NoReduce   0x01  /* Cannot EXPRDUP_REDUCE this Expr */
2792 #define EP_Immutable  0x02  /* Do not change this Expr node */
2793 
2794 /* The ExprSetVVAProperty() macro is used for Verification, Validation,
2795 ** and Accreditation only.  It works like ExprSetProperty() during VVA
2796 ** processes but is a no-op for delivery.
2797 */
2798 #ifdef SQLITE_DEBUG
2799 # define ExprSetVVAProperty(E,P)   (E)->vvaFlags|=(P)
2800 # define ExprHasVVAProperty(E,P)   (((E)->vvaFlags&(P))!=0)
2801 # define ExprClearVVAProperties(E) (E)->vvaFlags = 0
2802 #else
2803 # define ExprSetVVAProperty(E,P)
2804 # define ExprHasVVAProperty(E,P)   0
2805 # define ExprClearVVAProperties(E)
2806 #endif
2807 
2808 /*
2809 ** Macros to determine the number of bytes required by a normal Expr
2810 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
2811 ** and an Expr struct with the EP_TokenOnly flag set.
2812 */
2813 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
2814 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
2815 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
2816 
2817 /*
2818 ** Flags passed to the sqlite3ExprDup() function. See the header comment
2819 ** above sqlite3ExprDup() for details.
2820 */
2821 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
2822 
2823 /*
2824 ** True if the expression passed as an argument was a function with
2825 ** an OVER() clause (a window function).
2826 */
2827 #ifdef SQLITE_OMIT_WINDOWFUNC
2828 # define IsWindowFunc(p) 0
2829 #else
2830 # define IsWindowFunc(p) ( \
2831     ExprHasProperty((p), EP_WinFunc) && p->y.pWin->eFrmType!=TK_FILTER \
2832  )
2833 #endif
2834 
2835 /*
2836 ** A list of expressions.  Each expression may optionally have a
2837 ** name.  An expr/name combination can be used in several ways, such
2838 ** as the list of "expr AS ID" fields following a "SELECT" or in the
2839 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
2840 ** also be used as the argument to a function, in which case the a.zName
2841 ** field is not used.
2842 **
2843 ** In order to try to keep memory usage down, the Expr.a.zEName field
2844 ** is used for multiple purposes:
2845 **
2846 **     eEName          Usage
2847 **    ----------       -------------------------
2848 **    ENAME_NAME       (1) the AS of result set column
2849 **                     (2) COLUMN= of an UPDATE
2850 **
2851 **    ENAME_TAB        DB.TABLE.NAME used to resolve names
2852 **                     of subqueries
2853 **
2854 **    ENAME_SPAN       Text of the original result set
2855 **                     expression.
2856 */
2857 struct ExprList {
2858   int nExpr;             /* Number of expressions on the list */
2859   struct ExprList_item { /* For each expression in the list */
2860     Expr *pExpr;            /* The parse tree for this expression */
2861     char *zEName;           /* Token associated with this expression */
2862     u8 sortFlags;           /* Mask of KEYINFO_ORDER_* flags */
2863     unsigned eEName :2;     /* Meaning of zEName */
2864     unsigned done :1;       /* A flag to indicate when processing is finished */
2865     unsigned reusable :1;   /* Constant expression is reusable */
2866     unsigned bSorterRef :1; /* Defer evaluation until after sorting */
2867     unsigned bNulls: 1;     /* True if explicit "NULLS FIRST/LAST" */
2868     union {
2869       struct {
2870         u16 iOrderByCol;      /* For ORDER BY, column number in result set */
2871         u16 iAlias;           /* Index into Parse.aAlias[] for zName */
2872       } x;
2873       int iConstExprReg;      /* Register in which Expr value is cached */
2874     } u;
2875   } a[1];                  /* One slot for each expression in the list */
2876 };
2877 
2878 /*
2879 ** Allowed values for Expr.a.eEName
2880 */
2881 #define ENAME_NAME  0       /* The AS clause of a result set */
2882 #define ENAME_SPAN  1       /* Complete text of the result set expression */
2883 #define ENAME_TAB   2       /* "DB.TABLE.NAME" for the result set */
2884 
2885 /*
2886 ** An instance of this structure can hold a simple list of identifiers,
2887 ** such as the list "a,b,c" in the following statements:
2888 **
2889 **      INSERT INTO t(a,b,c) VALUES ...;
2890 **      CREATE INDEX idx ON t(a,b,c);
2891 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
2892 **
2893 ** The IdList.a.idx field is used when the IdList represents the list of
2894 ** column names after a table name in an INSERT statement.  In the statement
2895 **
2896 **     INSERT INTO t(a,b,c) ...
2897 **
2898 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
2899 */
2900 struct IdList {
2901   struct IdList_item {
2902     char *zName;      /* Name of the identifier */
2903     int idx;          /* Index in some Table.aCol[] of a column named zName */
2904   } *a;
2905   int nId;         /* Number of identifiers on the list */
2906 };
2907 
2908 /*
2909 ** The following structure describes the FROM clause of a SELECT statement.
2910 ** Each table or subquery in the FROM clause is a separate element of
2911 ** the SrcList.a[] array.
2912 **
2913 ** With the addition of multiple database support, the following structure
2914 ** can also be used to describe a particular table such as the table that
2915 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
2916 ** such a table must be a simple name: ID.  But in SQLite, the table can
2917 ** now be identified by a database name, a dot, then the table name: ID.ID.
2918 **
2919 ** The jointype starts out showing the join type between the current table
2920 ** and the next table on the list.  The parser builds the list this way.
2921 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
2922 ** jointype expresses the join between the table and the previous table.
2923 **
2924 ** In the colUsed field, the high-order bit (bit 63) is set if the table
2925 ** contains more than 63 columns and the 64-th or later column is used.
2926 */
2927 struct SrcList {
2928   int nSrc;        /* Number of tables or subqueries in the FROM clause */
2929   u32 nAlloc;      /* Number of entries allocated in a[] below */
2930   struct SrcList_item {
2931     Schema *pSchema;  /* Schema to which this item is fixed */
2932     char *zDatabase;  /* Name of database holding this table */
2933     char *zName;      /* Name of the table */
2934     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
2935     Table *pTab;      /* An SQL table corresponding to zName */
2936     Select *pSelect;  /* A SELECT statement used in place of a table name */
2937     int addrFillSub;  /* Address of subroutine to manifest a subquery */
2938     int regReturn;    /* Register holding return address of addrFillSub */
2939     int regResult;    /* Registers holding results of a co-routine */
2940     struct {
2941       u8 jointype;      /* Type of join between this table and the previous */
2942       unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
2943       unsigned isIndexedBy :1;   /* True if there is an INDEXED BY clause */
2944       unsigned isTabFunc :1;     /* True if table-valued-function syntax */
2945       unsigned isCorrelated :1;  /* True if sub-query is correlated */
2946       unsigned viaCoroutine :1;  /* Implemented as a co-routine */
2947       unsigned isRecursive :1;   /* True for recursive reference in WITH */
2948       unsigned fromDDL :1;       /* Comes from sqlite_schema */
2949     } fg;
2950     int iCursor;      /* The VDBE cursor number used to access this table */
2951     Expr *pOn;        /* The ON clause of a join */
2952     IdList *pUsing;   /* The USING clause of a join */
2953     Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
2954     union {
2955       char *zIndexedBy;    /* Identifier from "INDEXED BY <zIndex>" clause */
2956       ExprList *pFuncArg;  /* Arguments to table-valued-function */
2957     } u1;
2958     Index *pIBIndex;  /* Index structure corresponding to u1.zIndexedBy */
2959   } a[1];             /* One entry for each identifier on the list */
2960 };
2961 
2962 /*
2963 ** Permitted values of the SrcList.a.jointype field
2964 */
2965 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
2966 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
2967 #define JT_NATURAL   0x0004    /* True for a "natural" join */
2968 #define JT_LEFT      0x0008    /* Left outer join */
2969 #define JT_RIGHT     0x0010    /* Right outer join */
2970 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
2971 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
2972 
2973 
2974 /*
2975 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
2976 ** and the WhereInfo.wctrlFlags member.
2977 **
2978 ** Value constraints (enforced via assert()):
2979 **     WHERE_USE_LIMIT  == SF_FixedLimit
2980 */
2981 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
2982 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
2983 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
2984 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
2985 #define WHERE_ONEPASS_MULTIROW 0x0008 /* ONEPASS is ok with multiple rows */
2986 #define WHERE_DUPLICATES_OK    0x0010 /* Ok to return a row more than once */
2987 #define WHERE_OR_SUBCLAUSE     0x0020 /* Processing a sub-WHERE as part of
2988                                       ** the OR optimization  */
2989 #define WHERE_GROUPBY          0x0040 /* pOrderBy is really a GROUP BY */
2990 #define WHERE_DISTINCTBY       0x0080 /* pOrderby is really a DISTINCT clause */
2991 #define WHERE_WANT_DISTINCT    0x0100 /* All output needs to be distinct */
2992 #define WHERE_SORTBYGROUP      0x0200 /* Support sqlite3WhereIsSorted() */
2993                         /*     0x0400    not currently used */
2994 #define WHERE_ORDERBY_LIMIT    0x0800 /* ORDERBY+LIMIT on the inner loop */
2995                         /*     0x1000    not currently used */
2996                         /*     0x2000    not currently used */
2997 #define WHERE_USE_LIMIT        0x4000 /* Use the LIMIT in cost estimates */
2998                         /*     0x8000    not currently used */
2999 
3000 /* Allowed return values from sqlite3WhereIsDistinct()
3001 */
3002 #define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
3003 #define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
3004 #define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
3005 #define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
3006 
3007 /*
3008 ** A NameContext defines a context in which to resolve table and column
3009 ** names.  The context consists of a list of tables (the pSrcList) field and
3010 ** a list of named expression (pEList).  The named expression list may
3011 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
3012 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
3013 ** pEList corresponds to the result set of a SELECT and is NULL for
3014 ** other statements.
3015 **
3016 ** NameContexts can be nested.  When resolving names, the inner-most
3017 ** context is searched first.  If no match is found, the next outer
3018 ** context is checked.  If there is still no match, the next context
3019 ** is checked.  This process continues until either a match is found
3020 ** or all contexts are check.  When a match is found, the nRef member of
3021 ** the context containing the match is incremented.
3022 **
3023 ** Each subquery gets a new NameContext.  The pNext field points to the
3024 ** NameContext in the parent query.  Thus the process of scanning the
3025 ** NameContext list corresponds to searching through successively outer
3026 ** subqueries looking for a match.
3027 */
3028 struct NameContext {
3029   Parse *pParse;       /* The parser */
3030   SrcList *pSrcList;   /* One or more tables used to resolve names */
3031   union {
3032     ExprList *pEList;    /* Optional list of result-set columns */
3033     AggInfo *pAggInfo;   /* Information about aggregates at this level */
3034     Upsert *pUpsert;     /* ON CONFLICT clause information from an upsert */
3035   } uNC;
3036   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
3037   int nRef;            /* Number of names resolved by this context */
3038   int nErr;            /* Number of errors encountered while resolving names */
3039   int ncFlags;         /* Zero or more NC_* flags defined below */
3040   Select *pWinSelect;  /* SELECT statement for any window functions */
3041 };
3042 
3043 /*
3044 ** Allowed values for the NameContext, ncFlags field.
3045 **
3046 ** Value constraints (all checked via assert()):
3047 **    NC_HasAgg    == SF_HasAgg    == EP_Agg
3048 **    NC_MinMaxAgg == SF_MinMaxAgg == SQLITE_FUNC_MINMAX
3049 **    NC_HasWin    == EP_Win
3050 **
3051 */
3052 #define NC_AllowAgg  0x00001  /* Aggregate functions are allowed here */
3053 #define NC_PartIdx   0x00002  /* True if resolving a partial index WHERE */
3054 #define NC_IsCheck   0x00004  /* True if resolving a CHECK constraint */
3055 #define NC_GenCol    0x00008  /* True for a GENERATED ALWAYS AS clause */
3056 #define NC_HasAgg    0x00010  /* One or more aggregate functions seen */
3057 #define NC_IdxExpr   0x00020  /* True if resolving columns of CREATE INDEX */
3058 #define NC_SelfRef   0x0002e  /* Combo: PartIdx, isCheck, GenCol, and IdxExpr */
3059 #define NC_VarSelect 0x00040  /* A correlated subquery has been seen */
3060 #define NC_UEList    0x00080  /* True if uNC.pEList is used */
3061 #define NC_UAggInfo  0x00100  /* True if uNC.pAggInfo is used */
3062 #define NC_UUpsert   0x00200  /* True if uNC.pUpsert is used */
3063 #define NC_MinMaxAgg 0x01000  /* min/max aggregates seen.  See note above */
3064 #define NC_Complex   0x02000  /* True if a function or subquery seen */
3065 #define NC_AllowWin  0x04000  /* Window functions are allowed here */
3066 #define NC_HasWin    0x08000  /* One or more window functions seen */
3067 #define NC_IsDDL     0x10000  /* Resolving names in a CREATE statement */
3068 #define NC_InAggFunc 0x20000  /* True if analyzing arguments to an agg func */
3069 #define NC_FromDDL   0x40000  /* SQL text comes from sqlite_schema */
3070 
3071 /*
3072 ** An instance of the following object describes a single ON CONFLICT
3073 ** clause in an upsert.
3074 **
3075 ** The pUpsertTarget field is only set if the ON CONFLICT clause includes
3076 ** conflict-target clause.  (In "ON CONFLICT(a,b)" the "(a,b)" is the
3077 ** conflict-target clause.)  The pUpsertTargetWhere is the optional
3078 ** WHERE clause used to identify partial unique indexes.
3079 **
3080 ** pUpsertSet is the list of column=expr terms of the UPDATE statement.
3081 ** The pUpsertSet field is NULL for a ON CONFLICT DO NOTHING.  The
3082 ** pUpsertWhere is the WHERE clause for the UPDATE and is NULL if the
3083 ** WHERE clause is omitted.
3084 */
3085 struct Upsert {
3086   ExprList *pUpsertTarget;  /* Optional description of conflict target */
3087   Expr *pUpsertTargetWhere; /* WHERE clause for partial index targets */
3088   ExprList *pUpsertSet;     /* The SET clause from an ON CONFLICT UPDATE */
3089   Expr *pUpsertWhere;       /* WHERE clause for the ON CONFLICT UPDATE */
3090   Upsert *pNextUpsert;      /* Next ON CONFLICT clause in the list */
3091   u8 isDoUpdate;            /* True for DO UPDATE.  False for DO NOTHING */
3092   /* Above this point is the parse tree for the ON CONFLICT clauses.
3093   ** The next group of fields stores intermediate data. */
3094   void *pToFree;            /* Free memory when deleting the Upsert object */
3095   /* All fields above are owned by the Upsert object and must be freed
3096   ** when the Upsert is destroyed.  The fields below are used to transfer
3097   ** information from the INSERT processing down into the UPDATE processing
3098   ** while generating code.  The fields below are owned by the INSERT
3099   ** statement and will be freed by INSERT processing. */
3100   Index *pUpsertIdx;        /* UNIQUE constraint specified by pUpsertTarget */
3101   SrcList *pUpsertSrc;      /* Table to be updated */
3102   int regData;              /* First register holding array of VALUES */
3103   int iDataCur;             /* Index of the data cursor */
3104   int iIdxCur;              /* Index of the first index cursor */
3105 };
3106 
3107 /*
3108 ** An instance of the following structure contains all information
3109 ** needed to generate code for a single SELECT statement.
3110 **
3111 ** See the header comment on the computeLimitRegisters() routine for a
3112 ** detailed description of the meaning of the iLimit and iOffset fields.
3113 **
3114 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
3115 ** These addresses must be stored so that we can go back and fill in
3116 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
3117 ** the number of columns in P2 can be computed at the same time
3118 ** as the OP_OpenEphm instruction is coded because not
3119 ** enough information about the compound query is known at that point.
3120 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
3121 ** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
3122 ** sequences for the ORDER BY clause.
3123 */
3124 struct Select {
3125   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
3126   LogEst nSelectRow;     /* Estimated number of result rows */
3127   u32 selFlags;          /* Various SF_* values */
3128   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
3129   u32 selId;             /* Unique identifier number for this SELECT */
3130   int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
3131   ExprList *pEList;      /* The fields of the result */
3132   SrcList *pSrc;         /* The FROM clause */
3133   Expr *pWhere;          /* The WHERE clause */
3134   ExprList *pGroupBy;    /* The GROUP BY clause */
3135   Expr *pHaving;         /* The HAVING clause */
3136   ExprList *pOrderBy;    /* The ORDER BY clause */
3137   Select *pPrior;        /* Prior select in a compound select statement */
3138   Select *pNext;         /* Next select to the left in a compound */
3139   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
3140   With *pWith;           /* WITH clause attached to this select. Or NULL. */
3141 #ifndef SQLITE_OMIT_WINDOWFUNC
3142   Window *pWin;          /* List of window functions */
3143   Window *pWinDefn;      /* List of named window definitions */
3144 #endif
3145 };
3146 
3147 /*
3148 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
3149 ** "Select Flag".
3150 **
3151 ** Value constraints (all checked via assert())
3152 **     SF_HasAgg     == NC_HasAgg
3153 **     SF_MinMaxAgg  == NC_MinMaxAgg     == SQLITE_FUNC_MINMAX
3154 **     SF_FixedLimit == WHERE_USE_LIMIT
3155 */
3156 #define SF_Distinct      0x0000001 /* Output should be DISTINCT */
3157 #define SF_All           0x0000002 /* Includes the ALL keyword */
3158 #define SF_Resolved      0x0000004 /* Identifiers have been resolved */
3159 #define SF_Aggregate     0x0000008 /* Contains agg functions or a GROUP BY */
3160 #define SF_HasAgg        0x0000010 /* Contains aggregate functions */
3161 #define SF_UsesEphemeral 0x0000020 /* Uses the OpenEphemeral opcode */
3162 #define SF_Expanded      0x0000040 /* sqlite3SelectExpand() called on this */
3163 #define SF_HasTypeInfo   0x0000080 /* FROM subqueries have Table metadata */
3164 #define SF_Compound      0x0000100 /* Part of a compound query */
3165 #define SF_Values        0x0000200 /* Synthesized from VALUES clause */
3166 #define SF_MultiValue    0x0000400 /* Single VALUES term with multiple rows */
3167 #define SF_NestedFrom    0x0000800 /* Part of a parenthesized FROM clause */
3168 #define SF_MinMaxAgg     0x0001000 /* Aggregate containing min() or max() */
3169 #define SF_Recursive     0x0002000 /* The recursive part of a recursive CTE */
3170 #define SF_FixedLimit    0x0004000 /* nSelectRow set by a constant LIMIT */
3171 #define SF_MaybeConvert  0x0008000 /* Need convertCompoundSelectToSubquery() */
3172 #define SF_Converted     0x0010000 /* By convertCompoundSelectToSubquery() */
3173 #define SF_IncludeHidden 0x0020000 /* Include hidden columns in output */
3174 #define SF_ComplexResult 0x0040000 /* Result contains subquery or function */
3175 #define SF_WhereBegin    0x0080000 /* Really a WhereBegin() call.  Debug Only */
3176 #define SF_WinRewrite    0x0100000 /* Window function rewrite accomplished */
3177 #define SF_View          0x0200000 /* SELECT statement is a view */
3178 #define SF_NoopOrderBy   0x0400000 /* ORDER BY is ignored for this query */
3179 #define SF_UpdateFrom    0x0800000 /* Statement is an UPDATE...FROM */
3180 
3181 /*
3182 ** The results of a SELECT can be distributed in several ways, as defined
3183 ** by one of the following macros.  The "SRT" prefix means "SELECT Result
3184 ** Type".
3185 **
3186 **     SRT_Union       Store results as a key in a temporary index
3187 **                     identified by pDest->iSDParm.
3188 **
3189 **     SRT_Except      Remove results from the temporary index pDest->iSDParm.
3190 **
3191 **     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
3192 **                     set is not empty.
3193 **
3194 **     SRT_Discard     Throw the results away.  This is used by SELECT
3195 **                     statements within triggers whose only purpose is
3196 **                     the side-effects of functions.
3197 **
3198 **     SRT_Output      Generate a row of output (using the OP_ResultRow
3199 **                     opcode) for each row in the result set.
3200 **
3201 **     SRT_Mem         Only valid if the result is a single column.
3202 **                     Store the first column of the first result row
3203 **                     in register pDest->iSDParm then abandon the rest
3204 **                     of the query.  This destination implies "LIMIT 1".
3205 **
3206 **     SRT_Set         The result must be a single column.  Store each
3207 **                     row of result as the key in table pDest->iSDParm.
3208 **                     Apply the affinity pDest->affSdst before storing
3209 **                     results.  Used to implement "IN (SELECT ...)".
3210 **
3211 **     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
3212 **                     the result there. The cursor is left open after
3213 **                     returning.  This is like SRT_Table except that
3214 **                     this destination uses OP_OpenEphemeral to create
3215 **                     the table first.
3216 **
3217 **     SRT_Coroutine   Generate a co-routine that returns a new row of
3218 **                     results each time it is invoked.  The entry point
3219 **                     of the co-routine is stored in register pDest->iSDParm
3220 **                     and the result row is stored in pDest->nDest registers
3221 **                     starting with pDest->iSdst.
3222 **
3223 **     SRT_Table       Store results in temporary table pDest->iSDParm.
3224 **     SRT_Fifo        This is like SRT_EphemTab except that the table
3225 **                     is assumed to already be open.  SRT_Fifo has
3226 **                     the additional property of being able to ignore
3227 **                     the ORDER BY clause.
3228 **
3229 **     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
3230 **                     But also use temporary table pDest->iSDParm+1 as
3231 **                     a record of all prior results and ignore any duplicate
3232 **                     rows.  Name means:  "Distinct Fifo".
3233 **
3234 **     SRT_Queue       Store results in priority queue pDest->iSDParm (really
3235 **                     an index).  Append a sequence number so that all entries
3236 **                     are distinct.
3237 **
3238 **     SRT_DistQueue   Store results in priority queue pDest->iSDParm only if
3239 **                     the same record has never been stored before.  The
3240 **                     index at pDest->iSDParm+1 hold all prior stores.
3241 **
3242 **     SRT_Upfrom      Store results in the temporary table already opened by
3243 **                     pDest->iSDParm. If (pDest->iSDParm<0), then the temp
3244 **                     table is an intkey table - in this case the first
3245 **                     column returned by the SELECT is used as the integer
3246 **                     key. If (pDest->iSDParm>0), then the table is an index
3247 **                     table. (pDest->iSDParm) is the number of key columns in
3248 **                     each index record in this case.
3249 */
3250 #define SRT_Union        1  /* Store result as keys in an index */
3251 #define SRT_Except       2  /* Remove result from a UNION index */
3252 #define SRT_Exists       3  /* Store 1 if the result is not empty */
3253 #define SRT_Discard      4  /* Do not save the results anywhere */
3254 #define SRT_DistFifo     5  /* Like SRT_Fifo, but unique results only */
3255 #define SRT_DistQueue    6  /* Like SRT_Queue, but unique results only */
3256 
3257 /* The DISTINCT clause is ignored for all of the above.  Not that
3258 ** IgnorableDistinct() implies IgnorableOrderby() */
3259 #define IgnorableDistinct(X) ((X->eDest)<=SRT_DistQueue)
3260 
3261 #define SRT_Queue        7  /* Store result in an queue */
3262 #define SRT_Fifo         8  /* Store result as data with an automatic rowid */
3263 
3264 /* The ORDER BY clause is ignored for all of the above */
3265 #define IgnorableOrderby(X) ((X->eDest)<=SRT_Fifo)
3266 
3267 #define SRT_Output       9  /* Output each row of result */
3268 #define SRT_Mem         10  /* Store result in a memory cell */
3269 #define SRT_Set         11  /* Store results as keys in an index */
3270 #define SRT_EphemTab    12  /* Create transient tab and store like SRT_Table */
3271 #define SRT_Coroutine   13  /* Generate a single row of result */
3272 #define SRT_Table       14  /* Store result as data with an automatic rowid */
3273 #define SRT_Upfrom      15  /* Store result as data with rowid */
3274 
3275 /*
3276 ** An instance of this object describes where to put of the results of
3277 ** a SELECT statement.
3278 */
3279 struct SelectDest {
3280   u8 eDest;            /* How to dispose of the results.  One of SRT_* above. */
3281   int iSDParm;         /* A parameter used by the eDest disposal method */
3282   int iSDParm2;        /* A second parameter for the eDest disposal method */
3283   int iSdst;           /* Base register where results are written */
3284   int nSdst;           /* Number of registers allocated */
3285   char *zAffSdst;      /* Affinity used when eDest==SRT_Set */
3286   ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
3287 };
3288 
3289 /*
3290 ** During code generation of statements that do inserts into AUTOINCREMENT
3291 ** tables, the following information is attached to the Table.u.autoInc.p
3292 ** pointer of each autoincrement table to record some side information that
3293 ** the code generator needs.  We have to keep per-table autoincrement
3294 ** information in case inserts are done within triggers.  Triggers do not
3295 ** normally coordinate their activities, but we do need to coordinate the
3296 ** loading and saving of autoincrement information.
3297 */
3298 struct AutoincInfo {
3299   AutoincInfo *pNext;   /* Next info block in a list of them all */
3300   Table *pTab;          /* Table this info block refers to */
3301   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
3302   int regCtr;           /* Memory register holding the rowid counter */
3303 };
3304 
3305 /*
3306 ** At least one instance of the following structure is created for each
3307 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
3308 ** statement. All such objects are stored in the linked list headed at
3309 ** Parse.pTriggerPrg and deleted once statement compilation has been
3310 ** completed.
3311 **
3312 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
3313 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
3314 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
3315 ** The Parse.pTriggerPrg list never contains two entries with the same
3316 ** values for both pTrigger and orconf.
3317 **
3318 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
3319 ** accessed (or set to 0 for triggers fired as a result of INSERT
3320 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
3321 ** a mask of new.* columns used by the program.
3322 */
3323 struct TriggerPrg {
3324   Trigger *pTrigger;      /* Trigger this program was coded from */
3325   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
3326   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
3327   int orconf;             /* Default ON CONFLICT policy */
3328   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
3329 };
3330 
3331 /*
3332 ** The yDbMask datatype for the bitmask of all attached databases.
3333 */
3334 #if SQLITE_MAX_ATTACHED>30
3335   typedef unsigned char yDbMask[(SQLITE_MAX_ATTACHED+9)/8];
3336 # define DbMaskTest(M,I)    (((M)[(I)/8]&(1<<((I)&7)))!=0)
3337 # define DbMaskZero(M)      memset((M),0,sizeof(M))
3338 # define DbMaskSet(M,I)     (M)[(I)/8]|=(1<<((I)&7))
3339 # define DbMaskAllZero(M)   sqlite3DbMaskAllZero(M)
3340 # define DbMaskNonZero(M)   (sqlite3DbMaskAllZero(M)==0)
3341 #else
3342   typedef unsigned int yDbMask;
3343 # define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
3344 # define DbMaskZero(M)      (M)=0
3345 # define DbMaskSet(M,I)     (M)|=(((yDbMask)1)<<(I))
3346 # define DbMaskAllZero(M)   (M)==0
3347 # define DbMaskNonZero(M)   (M)!=0
3348 #endif
3349 
3350 /*
3351 ** An SQL parser context.  A copy of this structure is passed through
3352 ** the parser and down into all the parser action routine in order to
3353 ** carry around information that is global to the entire parse.
3354 **
3355 ** The structure is divided into two parts.  When the parser and code
3356 ** generate call themselves recursively, the first part of the structure
3357 ** is constant but the second part is reset at the beginning and end of
3358 ** each recursion.
3359 **
3360 ** The nTableLock and aTableLock variables are only used if the shared-cache
3361 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
3362 ** used to store the set of table-locks required by the statement being
3363 ** compiled. Function sqlite3TableLock() is used to add entries to the
3364 ** list.
3365 */
3366 struct Parse {
3367   sqlite3 *db;         /* The main database structure */
3368   char *zErrMsg;       /* An error message */
3369   Vdbe *pVdbe;         /* An engine for executing database bytecode */
3370   int rc;              /* Return code from execution */
3371   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
3372   u8 checkSchema;      /* Causes schema cookie check after an error */
3373   u8 nested;           /* Number of nested calls to the parser/code generator */
3374   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
3375   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
3376   u8 mayAbort;         /* True if statement may throw an ABORT exception */
3377   u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
3378   u8 okConstFactor;    /* OK to factor out constants */
3379   u8 disableLookaside; /* Number of times lookaside has been disabled */
3380   u8 disableVtab;      /* Disable all virtual tables for this parse */
3381   int nRangeReg;       /* Size of the temporary register block */
3382   int iRangeReg;       /* First register in temporary register block */
3383   int nErr;            /* Number of errors seen */
3384   int nTab;            /* Number of previously allocated VDBE cursors */
3385   int nMem;            /* Number of memory cells used so far */
3386   int szOpAlloc;       /* Bytes of memory space allocated for Vdbe.aOp[] */
3387   int iSelfTab;        /* Table associated with an index on expr, or negative
3388                        ** of the base register during check-constraint eval */
3389   int nLabel;          /* The *negative* of the number of labels used */
3390   int nLabelAlloc;     /* Number of slots in aLabel */
3391   int *aLabel;         /* Space to hold the labels */
3392   ExprList *pConstExpr;/* Constant expressions */
3393   Token constraintName;/* Name of the constraint currently being parsed */
3394   yDbMask writeMask;   /* Start a write transaction on these databases */
3395   yDbMask cookieMask;  /* Bitmask of schema verified databases */
3396   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
3397   int regRoot;         /* Register holding root page number for new objects */
3398   int nMaxArg;         /* Max args passed to user function by sub-program */
3399   int nSelect;         /* Number of SELECT stmts. Counter for Select.selId */
3400 #ifndef SQLITE_OMIT_SHARED_CACHE
3401   int nTableLock;        /* Number of locks in aTableLock */
3402   TableLock *aTableLock; /* Required table locks for shared-cache mode */
3403 #endif
3404   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
3405   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
3406   Table *pTriggerTab;  /* Table triggers are being coded for */
3407   Parse *pParentParse; /* Parent parser if this parser is nested */
3408   AggInfo *pAggList;   /* List of all AggInfo objects */
3409   int addrCrTab;       /* Address of OP_CreateBtree opcode on CREATE TABLE */
3410   u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
3411   u32 oldmask;         /* Mask of old.* columns referenced */
3412   u32 newmask;         /* Mask of new.* columns referenced */
3413   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
3414   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
3415   u8 disableTriggers;  /* True to disable triggers */
3416 
3417   /**************************************************************************
3418   ** Fields above must be initialized to zero.  The fields that follow,
3419   ** down to the beginning of the recursive section, do not need to be
3420   ** initialized as they will be set before being used.  The boundary is
3421   ** determined by offsetof(Parse,aTempReg).
3422   **************************************************************************/
3423 
3424   int aTempReg[8];        /* Holding area for temporary registers */
3425   Token sNameToken;       /* Token with unqualified schema object name */
3426 
3427   /************************************************************************
3428   ** Above is constant between recursions.  Below is reset before and after
3429   ** each recursion.  The boundary between these two regions is determined
3430   ** using offsetof(Parse,sLastToken) so the sLastToken field must be the
3431   ** first field in the recursive region.
3432   ************************************************************************/
3433 
3434   Token sLastToken;       /* The last token parsed */
3435   ynVar nVar;               /* Number of '?' variables seen in the SQL so far */
3436   u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
3437   u8 explain;               /* True if the EXPLAIN flag is found on the query */
3438   u8 eParseMode;            /* PARSE_MODE_XXX constant */
3439 #ifndef SQLITE_OMIT_VIRTUALTABLE
3440   int nVtabLock;            /* Number of virtual tables to lock */
3441 #endif
3442   int nHeight;              /* Expression tree height of current sub-select */
3443 #ifndef SQLITE_OMIT_EXPLAIN
3444   int addrExplain;          /* Address of current OP_Explain opcode */
3445 #endif
3446   VList *pVList;            /* Mapping between variable names and numbers */
3447   Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
3448   const char *zTail;        /* All SQL text past the last semicolon parsed */
3449   Table *pNewTable;         /* A table being constructed by CREATE TABLE */
3450   Index *pNewIndex;         /* An index being constructed by CREATE INDEX.
3451                             ** Also used to hold redundant UNIQUE constraints
3452                             ** during a RENAME COLUMN */
3453   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
3454   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
3455 #ifndef SQLITE_OMIT_VIRTUALTABLE
3456   Token sArg;               /* Complete text of a module argument */
3457   Table **apVtabLock;       /* Pointer to virtual tables needing locking */
3458 #endif
3459   Table *pZombieTab;        /* List of Table objects to delete after code gen */
3460   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
3461   With *pWith;              /* Current WITH clause, or NULL */
3462   With *pWithToFree;        /* Free this WITH object at the end of the parse */
3463 #ifndef SQLITE_OMIT_ALTERTABLE
3464   RenameToken *pRename;     /* Tokens subject to renaming by ALTER TABLE */
3465 #endif
3466 };
3467 
3468 #define PARSE_MODE_NORMAL        0
3469 #define PARSE_MODE_DECLARE_VTAB  1
3470 #define PARSE_MODE_RENAME        2
3471 #define PARSE_MODE_UNMAP         3
3472 
3473 /*
3474 ** Sizes and pointers of various parts of the Parse object.
3475 */
3476 #define PARSE_HDR_SZ offsetof(Parse,aTempReg) /* Recursive part w/o aColCache*/
3477 #define PARSE_RECURSE_SZ offsetof(Parse,sLastToken)    /* Recursive part */
3478 #define PARSE_TAIL_SZ (sizeof(Parse)-PARSE_RECURSE_SZ) /* Non-recursive part */
3479 #define PARSE_TAIL(X) (((char*)(X))+PARSE_RECURSE_SZ)  /* Pointer to tail */
3480 
3481 /*
3482 ** Return true if currently inside an sqlite3_declare_vtab() call.
3483 */
3484 #ifdef SQLITE_OMIT_VIRTUALTABLE
3485   #define IN_DECLARE_VTAB 0
3486 #else
3487   #define IN_DECLARE_VTAB (pParse->eParseMode==PARSE_MODE_DECLARE_VTAB)
3488 #endif
3489 
3490 #if defined(SQLITE_OMIT_ALTERTABLE)
3491   #define IN_RENAME_OBJECT 0
3492 #else
3493   #define IN_RENAME_OBJECT (pParse->eParseMode>=PARSE_MODE_RENAME)
3494 #endif
3495 
3496 #if defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_OMIT_ALTERTABLE)
3497   #define IN_SPECIAL_PARSE 0
3498 #else
3499   #define IN_SPECIAL_PARSE (pParse->eParseMode!=PARSE_MODE_NORMAL)
3500 #endif
3501 
3502 /*
3503 ** An instance of the following structure can be declared on a stack and used
3504 ** to save the Parse.zAuthContext value so that it can be restored later.
3505 */
3506 struct AuthContext {
3507   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
3508   Parse *pParse;              /* The Parse structure */
3509 };
3510 
3511 /*
3512 ** Bitfield flags for P5 value in various opcodes.
3513 **
3514 ** Value constraints (enforced via assert()):
3515 **    OPFLAG_LENGTHARG    == SQLITE_FUNC_LENGTH
3516 **    OPFLAG_TYPEOFARG    == SQLITE_FUNC_TYPEOF
3517 **    OPFLAG_BULKCSR      == BTREE_BULKLOAD
3518 **    OPFLAG_SEEKEQ       == BTREE_SEEK_EQ
3519 **    OPFLAG_FORDELETE    == BTREE_FORDELETE
3520 **    OPFLAG_SAVEPOSITION == BTREE_SAVEPOSITION
3521 **    OPFLAG_AUXDELETE    == BTREE_AUXDELETE
3522 */
3523 #define OPFLAG_NCHANGE       0x01    /* OP_Insert: Set to update db->nChange */
3524                                      /* Also used in P2 (not P5) of OP_Delete */
3525 #define OPFLAG_NOCHNG        0x01    /* OP_VColumn nochange for UPDATE */
3526 #define OPFLAG_EPHEM         0x01    /* OP_Column: Ephemeral output is ok */
3527 #define OPFLAG_LASTROWID     0x20    /* Set to update db->lastRowid */
3528 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
3529 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
3530 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
3531 #define OPFLAG_ISNOOP        0x40    /* OP_Delete does pre-update-hook only */
3532 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
3533 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
3534 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
3535 #define OPFLAG_SEEKEQ        0x02    /* OP_Open** cursor uses EQ seek only */
3536 #define OPFLAG_FORDELETE     0x08    /* OP_Open should use BTREE_FORDELETE */
3537 #define OPFLAG_P2ISREG       0x10    /* P2 to OP_Open** is a register number */
3538 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
3539 #define OPFLAG_SAVEPOSITION  0x02    /* OP_Delete/Insert: save cursor pos */
3540 #define OPFLAG_AUXDELETE     0x04    /* OP_Delete: index in a DELETE op */
3541 #define OPFLAG_NOCHNG_MAGIC  0x6d    /* OP_MakeRecord: serialtype 10 is ok */
3542 #define OPFLAG_PREFORMAT     0x80    /* OP_Insert uses preformatted cell */
3543 
3544 /*
3545  * Each trigger present in the database schema is stored as an instance of
3546  * struct Trigger.
3547  *
3548  * Pointers to instances of struct Trigger are stored in two ways.
3549  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
3550  *    database). This allows Trigger structures to be retrieved by name.
3551  * 2. All triggers associated with a single table form a linked list, using the
3552  *    pNext member of struct Trigger. A pointer to the first element of the
3553  *    linked list is stored as the "pTrigger" member of the associated
3554  *    struct Table.
3555  *
3556  * The "step_list" member points to the first element of a linked list
3557  * containing the SQL statements specified as the trigger program.
3558  */
3559 struct Trigger {
3560   char *zName;            /* The name of the trigger                        */
3561   char *table;            /* The table or view to which the trigger applies */
3562   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
3563   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
3564   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
3565   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
3566                              the <column-list> is stored here */
3567   Schema *pSchema;        /* Schema containing the trigger */
3568   Schema *pTabSchema;     /* Schema containing the table */
3569   TriggerStep *step_list; /* Link list of trigger program steps             */
3570   Trigger *pNext;         /* Next trigger associated with the table */
3571 };
3572 
3573 /*
3574 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
3575 ** determine which.
3576 **
3577 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
3578 ** In that cases, the constants below can be ORed together.
3579 */
3580 #define TRIGGER_BEFORE  1
3581 #define TRIGGER_AFTER   2
3582 
3583 /*
3584  * An instance of struct TriggerStep is used to store a single SQL statement
3585  * that is a part of a trigger-program.
3586  *
3587  * Instances of struct TriggerStep are stored in a singly linked list (linked
3588  * using the "pNext" member) referenced by the "step_list" member of the
3589  * associated struct Trigger instance. The first element of the linked list is
3590  * the first step of the trigger-program.
3591  *
3592  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
3593  * "SELECT" statement. The meanings of the other members is determined by the
3594  * value of "op" as follows:
3595  *
3596  * (op == TK_INSERT)
3597  * orconf    -> stores the ON CONFLICT algorithm
3598  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
3599  *              this stores a pointer to the SELECT statement. Otherwise NULL.
3600  * zTarget   -> Dequoted name of the table to insert into.
3601  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
3602  *              this stores values to be inserted. Otherwise NULL.
3603  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
3604  *              statement, then this stores the column-names to be
3605  *              inserted into.
3606  *
3607  * (op == TK_DELETE)
3608  * zTarget   -> Dequoted name of the table to delete from.
3609  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
3610  *              Otherwise NULL.
3611  *
3612  * (op == TK_UPDATE)
3613  * zTarget   -> Dequoted name of the table to update.
3614  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
3615  *              Otherwise NULL.
3616  * pExprList -> A list of the columns to update and the expressions to update
3617  *              them to. See sqlite3Update() documentation of "pChanges"
3618  *              argument.
3619  *
3620  */
3621 struct TriggerStep {
3622   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
3623   u8 orconf;           /* OE_Rollback etc. */
3624   Trigger *pTrig;      /* The trigger that this step is a part of */
3625   Select *pSelect;     /* SELECT statement or RHS of INSERT INTO SELECT ... */
3626   char *zTarget;       /* Target table for DELETE, UPDATE, INSERT */
3627   SrcList *pFrom;      /* FROM clause for UPDATE statement (if any) */
3628   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
3629   ExprList *pExprList; /* SET clause for UPDATE */
3630   IdList *pIdList;     /* Column names for INSERT */
3631   Upsert *pUpsert;     /* Upsert clauses on an INSERT */
3632   char *zSpan;         /* Original SQL text of this command */
3633   TriggerStep *pNext;  /* Next in the link-list */
3634   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
3635 };
3636 
3637 /*
3638 ** The following structure contains information used by the sqliteFix...
3639 ** routines as they walk the parse tree to make database references
3640 ** explicit.
3641 */
3642 typedef struct DbFixer DbFixer;
3643 struct DbFixer {
3644   Parse *pParse;      /* The parsing context.  Error messages written here */
3645   Schema *pSchema;    /* Fix items to this schema */
3646   u8 bTemp;           /* True for TEMP schema entries */
3647   const char *zDb;    /* Make sure all objects are contained in this database */
3648   const char *zType;  /* Type of the container - used for error messages */
3649   const Token *pName; /* Name of the container - used for error messages */
3650 };
3651 
3652 /*
3653 ** An objected used to accumulate the text of a string where we
3654 ** do not necessarily know how big the string will be in the end.
3655 */
3656 struct sqlite3_str {
3657   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
3658   char *zText;         /* The string collected so far */
3659   u32  nAlloc;         /* Amount of space allocated in zText */
3660   u32  mxAlloc;        /* Maximum allowed allocation.  0 for no malloc usage */
3661   u32  nChar;          /* Length of the string so far */
3662   u8   accError;       /* SQLITE_NOMEM or SQLITE_TOOBIG */
3663   u8   printfFlags;    /* SQLITE_PRINTF flags below */
3664 };
3665 #define SQLITE_PRINTF_INTERNAL 0x01  /* Internal-use-only converters allowed */
3666 #define SQLITE_PRINTF_SQLFUNC  0x02  /* SQL function arguments to VXPrintf */
3667 #define SQLITE_PRINTF_MALLOCED 0x04  /* True if xText is allocated space */
3668 
3669 #define isMalloced(X)  (((X)->printfFlags & SQLITE_PRINTF_MALLOCED)!=0)
3670 
3671 
3672 /*
3673 ** A pointer to this structure is used to communicate information
3674 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
3675 */
3676 typedef struct {
3677   sqlite3 *db;        /* The database being initialized */
3678   char **pzErrMsg;    /* Error message stored here */
3679   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
3680   int rc;             /* Result code stored here */
3681   u32 mInitFlags;     /* Flags controlling error messages */
3682   u32 nInitRow;       /* Number of rows processed */
3683   Pgno mxPage;        /* Maximum page number.  0 for no limit. */
3684 } InitData;
3685 
3686 /*
3687 ** Allowed values for mInitFlags
3688 */
3689 #define INITFLAG_AlterTable   0x0001  /* This is a reparse after ALTER TABLE */
3690 
3691 /*
3692 ** Structure containing global configuration data for the SQLite library.
3693 **
3694 ** This structure also contains some state information.
3695 */
3696 struct Sqlite3Config {
3697   int bMemstat;                     /* True to enable memory status */
3698   u8 bCoreMutex;                    /* True to enable core mutexing */
3699   u8 bFullMutex;                    /* True to enable full mutexing */
3700   u8 bOpenUri;                      /* True to interpret filenames as URIs */
3701   u8 bUseCis;                       /* Use covering indices for full-scans */
3702   u8 bSmallMalloc;                  /* Avoid large memory allocations if true */
3703   u8 bExtraSchemaChecks;            /* Verify type,name,tbl_name in schema */
3704   int mxStrlen;                     /* Maximum string length */
3705   int neverCorrupt;                 /* Database is always well-formed */
3706   int szLookaside;                  /* Default lookaside buffer size */
3707   int nLookaside;                   /* Default lookaside buffer count */
3708   int nStmtSpill;                   /* Stmt-journal spill-to-disk threshold */
3709   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
3710   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
3711   sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
3712   void *pHeap;                      /* Heap storage space */
3713   int nHeap;                        /* Size of pHeap[] */
3714   int mnReq, mxReq;                 /* Min and max heap requests sizes */
3715   sqlite3_int64 szMmap;             /* mmap() space per open file */
3716   sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
3717   void *pPage;                      /* Page cache memory */
3718   int szPage;                       /* Size of each page in pPage[] */
3719   int nPage;                        /* Number of pages in pPage[] */
3720   int mxParserStack;                /* maximum depth of the parser stack */
3721   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
3722   u32 szPma;                        /* Maximum Sorter PMA size */
3723   /* The above might be initialized to non-zero.  The following need to always
3724   ** initially be zero, however. */
3725   int isInit;                       /* True after initialization has finished */
3726   int inProgress;                   /* True while initialization in progress */
3727   int isMutexInit;                  /* True after mutexes are initialized */
3728   int isMallocInit;                 /* True after malloc is initialized */
3729   int isPCacheInit;                 /* True after malloc is initialized */
3730   int nRefInitMutex;                /* Number of users of pInitMutex */
3731   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
3732   void (*xLog)(void*,int,const char*); /* Function for logging */
3733   void *pLogArg;                       /* First argument to xLog() */
3734 #ifdef SQLITE_ENABLE_SQLLOG
3735   void(*xSqllog)(void*,sqlite3*,const char*, int);
3736   void *pSqllogArg;
3737 #endif
3738 #ifdef SQLITE_VDBE_COVERAGE
3739   /* The following callback (if not NULL) is invoked on every VDBE branch
3740   ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
3741   */
3742   void (*xVdbeBranch)(void*,unsigned iSrcLine,u8 eThis,u8 eMx);  /* Callback */
3743   void *pVdbeBranchArg;                                     /* 1st argument */
3744 #endif
3745 #ifdef SQLITE_ENABLE_DESERIALIZE
3746   sqlite3_int64 mxMemdbSize;        /* Default max memdb size */
3747 #endif
3748 #ifndef SQLITE_UNTESTABLE
3749   int (*xTestCallback)(int);        /* Invoked by sqlite3FaultSim() */
3750 #endif
3751   int bLocaltimeFault;              /* True to fail localtime() calls */
3752   int iOnceResetThreshold;          /* When to reset OP_Once counters */
3753   u32 szSorterRef;                  /* Min size in bytes to use sorter-refs */
3754   unsigned int iPrngSeed;           /* Alternative fixed seed for the PRNG */
3755 };
3756 
3757 /*
3758 ** This macro is used inside of assert() statements to indicate that
3759 ** the assert is only valid on a well-formed database.  Instead of:
3760 **
3761 **     assert( X );
3762 **
3763 ** One writes:
3764 **
3765 **     assert( X || CORRUPT_DB );
3766 **
3767 ** CORRUPT_DB is true during normal operation.  CORRUPT_DB does not indicate
3768 ** that the database is definitely corrupt, only that it might be corrupt.
3769 ** For most test cases, CORRUPT_DB is set to false using a special
3770 ** sqlite3_test_control().  This enables assert() statements to prove
3771 ** things that are always true for well-formed databases.
3772 */
3773 #define CORRUPT_DB  (sqlite3Config.neverCorrupt==0)
3774 
3775 /*
3776 ** Context pointer passed down through the tree-walk.
3777 */
3778 struct Walker {
3779   Parse *pParse;                            /* Parser context.  */
3780   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
3781   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
3782   void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
3783   int walkerDepth;                          /* Number of subqueries */
3784   u16 eCode;                                /* A small processing code */
3785   union {                                   /* Extra data for callback */
3786     NameContext *pNC;                         /* Naming context */
3787     int n;                                    /* A counter */
3788     int iCur;                                 /* A cursor number */
3789     SrcList *pSrcList;                        /* FROM clause */
3790     struct SrcCount *pSrcCount;               /* Counting column references */
3791     struct CCurHint *pCCurHint;               /* Used by codeCursorHint() */
3792     int *aiCol;                               /* array of column indexes */
3793     struct IdxCover *pIdxCover;               /* Check for index coverage */
3794     struct IdxExprTrans *pIdxTrans;           /* Convert idxed expr to column */
3795     ExprList *pGroupBy;                       /* GROUP BY clause */
3796     Select *pSelect;                          /* HAVING to WHERE clause ctx */
3797     struct WindowRewrite *pRewrite;           /* Window rewrite context */
3798     struct WhereConst *pConst;                /* WHERE clause constants */
3799     struct RenameCtx *pRename;                /* RENAME COLUMN context */
3800     struct Table *pTab;                       /* Table of generated column */
3801     struct SrcList_item *pSrcItem;            /* A single FROM clause item */
3802   } u;
3803 };
3804 
3805 /* Forward declarations */
3806 int sqlite3WalkExpr(Walker*, Expr*);
3807 int sqlite3WalkExprList(Walker*, ExprList*);
3808 int sqlite3WalkSelect(Walker*, Select*);
3809 int sqlite3WalkSelectExpr(Walker*, Select*);
3810 int sqlite3WalkSelectFrom(Walker*, Select*);
3811 int sqlite3ExprWalkNoop(Walker*, Expr*);
3812 int sqlite3SelectWalkNoop(Walker*, Select*);
3813 int sqlite3SelectWalkFail(Walker*, Select*);
3814 int sqlite3WalkerDepthIncrease(Walker*,Select*);
3815 void sqlite3WalkerDepthDecrease(Walker*,Select*);
3816 
3817 #ifdef SQLITE_DEBUG
3818 void sqlite3SelectWalkAssert2(Walker*, Select*);
3819 #endif
3820 
3821 /*
3822 ** Return code from the parse-tree walking primitives and their
3823 ** callbacks.
3824 */
3825 #define WRC_Continue    0   /* Continue down into children */
3826 #define WRC_Prune       1   /* Omit children but continue walking siblings */
3827 #define WRC_Abort       2   /* Abandon the tree walk */
3828 
3829 /*
3830 ** An instance of this structure represents a set of one or more CTEs
3831 ** (common table expressions) created by a single WITH clause.
3832 */
3833 struct With {
3834   int nCte;                       /* Number of CTEs in the WITH clause */
3835   With *pOuter;                   /* Containing WITH clause, or NULL */
3836   struct Cte {                    /* For each CTE in the WITH clause.... */
3837     char *zName;                    /* Name of this CTE */
3838     ExprList *pCols;                /* List of explicit column names, or NULL */
3839     Select *pSelect;                /* The definition of this CTE */
3840     const char *zCteErr;            /* Error message for circular references */
3841   } a[1];
3842 };
3843 
3844 #ifdef SQLITE_DEBUG
3845 /*
3846 ** An instance of the TreeView object is used for printing the content of
3847 ** data structures on sqlite3DebugPrintf() using a tree-like view.
3848 */
3849 struct TreeView {
3850   int iLevel;             /* Which level of the tree we are on */
3851   u8  bLine[100];         /* Draw vertical in column i if bLine[i] is true */
3852 };
3853 #endif /* SQLITE_DEBUG */
3854 
3855 /*
3856 ** This object is used in various ways, most (but not all) related to window
3857 ** functions.
3858 **
3859 **   (1) A single instance of this structure is attached to the
3860 **       the Expr.y.pWin field for each window function in an expression tree.
3861 **       This object holds the information contained in the OVER clause,
3862 **       plus additional fields used during code generation.
3863 **
3864 **   (2) All window functions in a single SELECT form a linked-list
3865 **       attached to Select.pWin.  The Window.pFunc and Window.pExpr
3866 **       fields point back to the expression that is the window function.
3867 **
3868 **   (3) The terms of the WINDOW clause of a SELECT are instances of this
3869 **       object on a linked list attached to Select.pWinDefn.
3870 **
3871 **   (4) For an aggregate function with a FILTER clause, an instance
3872 **       of this object is stored in Expr.y.pWin with eFrmType set to
3873 **       TK_FILTER. In this case the only field used is Window.pFilter.
3874 **
3875 ** The uses (1) and (2) are really the same Window object that just happens
3876 ** to be accessible in two different ways.  Use case (3) are separate objects.
3877 */
3878 struct Window {
3879   char *zName;            /* Name of window (may be NULL) */
3880   char *zBase;            /* Name of base window for chaining (may be NULL) */
3881   ExprList *pPartition;   /* PARTITION BY clause */
3882   ExprList *pOrderBy;     /* ORDER BY clause */
3883   u8 eFrmType;            /* TK_RANGE, TK_GROUPS, TK_ROWS, or 0 */
3884   u8 eStart;              /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
3885   u8 eEnd;                /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
3886   u8 bImplicitFrame;      /* True if frame was implicitly specified */
3887   u8 eExclude;            /* TK_NO, TK_CURRENT, TK_TIES, TK_GROUP, or 0 */
3888   Expr *pStart;           /* Expression for "<expr> PRECEDING" */
3889   Expr *pEnd;             /* Expression for "<expr> FOLLOWING" */
3890   Window **ppThis;        /* Pointer to this object in Select.pWin list */
3891   Window *pNextWin;       /* Next window function belonging to this SELECT */
3892   Expr *pFilter;          /* The FILTER expression */
3893   FuncDef *pFunc;         /* The function */
3894   int iEphCsr;            /* Partition buffer or Peer buffer */
3895   int regAccum;           /* Accumulator */
3896   int regResult;          /* Interim result */
3897   int csrApp;             /* Function cursor (used by min/max) */
3898   int regApp;             /* Function register (also used by min/max) */
3899   int regPart;            /* Array of registers for PARTITION BY values */
3900   Expr *pOwner;           /* Expression object this window is attached to */
3901   int nBufferCol;         /* Number of columns in buffer table */
3902   int iArgCol;            /* Offset of first argument for this function */
3903   int regOne;             /* Register containing constant value 1 */
3904   int regStartRowid;
3905   int regEndRowid;
3906   u8 bExprArgs;           /* Defer evaluation of window function arguments
3907                           ** due to the SQLITE_SUBTYPE flag */
3908 };
3909 
3910 #ifndef SQLITE_OMIT_WINDOWFUNC
3911 void sqlite3WindowDelete(sqlite3*, Window*);
3912 void sqlite3WindowUnlinkFromSelect(Window*);
3913 void sqlite3WindowListDelete(sqlite3 *db, Window *p);
3914 Window *sqlite3WindowAlloc(Parse*, int, int, Expr*, int , Expr*, u8);
3915 void sqlite3WindowAttach(Parse*, Expr*, Window*);
3916 void sqlite3WindowLink(Select *pSel, Window *pWin);
3917 int sqlite3WindowCompare(Parse*, Window*, Window*, int);
3918 void sqlite3WindowCodeInit(Parse*, Select*);
3919 void sqlite3WindowCodeStep(Parse*, Select*, WhereInfo*, int, int);
3920 int sqlite3WindowRewrite(Parse*, Select*);
3921 void sqlite3WindowUpdate(Parse*, Window*, Window*, FuncDef*);
3922 Window *sqlite3WindowDup(sqlite3 *db, Expr *pOwner, Window *p);
3923 Window *sqlite3WindowListDup(sqlite3 *db, Window *p);
3924 void sqlite3WindowFunctions(void);
3925 void sqlite3WindowChain(Parse*, Window*, Window*);
3926 Window *sqlite3WindowAssemble(Parse*, Window*, ExprList*, ExprList*, Token*);
3927 #else
3928 # define sqlite3WindowDelete(a,b)
3929 # define sqlite3WindowFunctions()
3930 # define sqlite3WindowAttach(a,b,c)
3931 #endif
3932 
3933 /*
3934 ** Assuming zIn points to the first byte of a UTF-8 character,
3935 ** advance zIn to point to the first byte of the next UTF-8 character.
3936 */
3937 #define SQLITE_SKIP_UTF8(zIn) {                        \
3938   if( (*(zIn++))>=0xc0 ){                              \
3939     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
3940   }                                                    \
3941 }
3942 
3943 /*
3944 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
3945 ** the same name but without the _BKPT suffix.  These macros invoke
3946 ** routines that report the line-number on which the error originated
3947 ** using sqlite3_log().  The routines also provide a convenient place
3948 ** to set a debugger breakpoint.
3949 */
3950 int sqlite3ReportError(int iErr, int lineno, const char *zType);
3951 int sqlite3CorruptError(int);
3952 int sqlite3MisuseError(int);
3953 int sqlite3CantopenError(int);
3954 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
3955 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
3956 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
3957 #ifdef SQLITE_DEBUG
3958   int sqlite3NomemError(int);
3959   int sqlite3IoerrnomemError(int);
3960 # define SQLITE_NOMEM_BKPT sqlite3NomemError(__LINE__)
3961 # define SQLITE_IOERR_NOMEM_BKPT sqlite3IoerrnomemError(__LINE__)
3962 #else
3963 # define SQLITE_NOMEM_BKPT SQLITE_NOMEM
3964 # define SQLITE_IOERR_NOMEM_BKPT SQLITE_IOERR_NOMEM
3965 #endif
3966 #if defined(SQLITE_DEBUG) || defined(SQLITE_ENABLE_CORRUPT_PGNO)
3967   int sqlite3CorruptPgnoError(int,Pgno);
3968 # define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptPgnoError(__LINE__,(P))
3969 #else
3970 # define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptError(__LINE__)
3971 #endif
3972 
3973 /*
3974 ** FTS3 and FTS4 both require virtual table support
3975 */
3976 #if defined(SQLITE_OMIT_VIRTUALTABLE)
3977 # undef SQLITE_ENABLE_FTS3
3978 # undef SQLITE_ENABLE_FTS4
3979 #endif
3980 
3981 /*
3982 ** FTS4 is really an extension for FTS3.  It is enabled using the
3983 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also call
3984 ** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
3985 */
3986 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
3987 # define SQLITE_ENABLE_FTS3 1
3988 #endif
3989 
3990 /*
3991 ** The ctype.h header is needed for non-ASCII systems.  It is also
3992 ** needed by FTS3 when FTS3 is included in the amalgamation.
3993 */
3994 #if !defined(SQLITE_ASCII) || \
3995     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
3996 # include <ctype.h>
3997 #endif
3998 
3999 /*
4000 ** The following macros mimic the standard library functions toupper(),
4001 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
4002 ** sqlite versions only work for ASCII characters, regardless of locale.
4003 */
4004 #ifdef SQLITE_ASCII
4005 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
4006 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
4007 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
4008 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
4009 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
4010 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
4011 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
4012 # define sqlite3Isquote(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x80)
4013 #else
4014 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
4015 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
4016 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
4017 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
4018 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
4019 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
4020 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
4021 # define sqlite3Isquote(x)   ((x)=='"'||(x)=='\''||(x)=='['||(x)=='`')
4022 #endif
4023 int sqlite3IsIdChar(u8);
4024 
4025 /*
4026 ** Internal function prototypes
4027 */
4028 int sqlite3StrICmp(const char*,const char*);
4029 int sqlite3Strlen30(const char*);
4030 #define sqlite3Strlen30NN(C) (strlen(C)&0x3fffffff)
4031 char *sqlite3ColumnType(Column*,char*);
4032 #define sqlite3StrNICmp sqlite3_strnicmp
4033 
4034 int sqlite3MallocInit(void);
4035 void sqlite3MallocEnd(void);
4036 void *sqlite3Malloc(u64);
4037 void *sqlite3MallocZero(u64);
4038 void *sqlite3DbMallocZero(sqlite3*, u64);
4039 void *sqlite3DbMallocRaw(sqlite3*, u64);
4040 void *sqlite3DbMallocRawNN(sqlite3*, u64);
4041 char *sqlite3DbStrDup(sqlite3*,const char*);
4042 char *sqlite3DbStrNDup(sqlite3*,const char*, u64);
4043 char *sqlite3DbSpanDup(sqlite3*,const char*,const char*);
4044 void *sqlite3Realloc(void*, u64);
4045 void *sqlite3DbReallocOrFree(sqlite3 *, void *, u64);
4046 void *sqlite3DbRealloc(sqlite3 *, void *, u64);
4047 void sqlite3DbFree(sqlite3*, void*);
4048 void sqlite3DbFreeNN(sqlite3*, void*);
4049 int sqlite3MallocSize(void*);
4050 int sqlite3DbMallocSize(sqlite3*, void*);
4051 void *sqlite3PageMalloc(int);
4052 void sqlite3PageFree(void*);
4053 void sqlite3MemSetDefault(void);
4054 #ifndef SQLITE_UNTESTABLE
4055 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
4056 #endif
4057 int sqlite3HeapNearlyFull(void);
4058 
4059 /*
4060 ** On systems with ample stack space and that support alloca(), make
4061 ** use of alloca() to obtain space for large automatic objects.  By default,
4062 ** obtain space from malloc().
4063 **
4064 ** The alloca() routine never returns NULL.  This will cause code paths
4065 ** that deal with sqlite3StackAlloc() failures to be unreachable.
4066 */
4067 #ifdef SQLITE_USE_ALLOCA
4068 # define sqlite3StackAllocRaw(D,N)   alloca(N)
4069 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
4070 # define sqlite3StackFree(D,P)
4071 #else
4072 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
4073 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
4074 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
4075 #endif
4076 
4077 /* Do not allow both MEMSYS5 and MEMSYS3 to be defined together.  If they
4078 ** are, disable MEMSYS3
4079 */
4080 #ifdef SQLITE_ENABLE_MEMSYS5
4081 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
4082 #undef SQLITE_ENABLE_MEMSYS3
4083 #endif
4084 #ifdef SQLITE_ENABLE_MEMSYS3
4085 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
4086 #endif
4087 
4088 
4089 #ifndef SQLITE_MUTEX_OMIT
4090   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
4091   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
4092   sqlite3_mutex *sqlite3MutexAlloc(int);
4093   int sqlite3MutexInit(void);
4094   int sqlite3MutexEnd(void);
4095 #endif
4096 #if !defined(SQLITE_MUTEX_OMIT) && !defined(SQLITE_MUTEX_NOOP)
4097   void sqlite3MemoryBarrier(void);
4098 #else
4099 # define sqlite3MemoryBarrier()
4100 #endif
4101 
4102 sqlite3_int64 sqlite3StatusValue(int);
4103 void sqlite3StatusUp(int, int);
4104 void sqlite3StatusDown(int, int);
4105 void sqlite3StatusHighwater(int, int);
4106 int sqlite3LookasideUsed(sqlite3*,int*);
4107 
4108 /* Access to mutexes used by sqlite3_status() */
4109 sqlite3_mutex *sqlite3Pcache1Mutex(void);
4110 sqlite3_mutex *sqlite3MallocMutex(void);
4111 
4112 #if defined(SQLITE_ENABLE_MULTITHREADED_CHECKS) && !defined(SQLITE_MUTEX_OMIT)
4113 void sqlite3MutexWarnOnContention(sqlite3_mutex*);
4114 #else
4115 # define sqlite3MutexWarnOnContention(x)
4116 #endif
4117 
4118 #ifndef SQLITE_OMIT_FLOATING_POINT
4119 # define EXP754 (((u64)0x7ff)<<52)
4120 # define MAN754 ((((u64)1)<<52)-1)
4121 # define IsNaN(X) (((X)&EXP754)==EXP754 && ((X)&MAN754)!=0)
4122   int sqlite3IsNaN(double);
4123 #else
4124 # define IsNaN(X)         0
4125 # define sqlite3IsNaN(X)  0
4126 #endif
4127 
4128 /*
4129 ** An instance of the following structure holds information about SQL
4130 ** functions arguments that are the parameters to the printf() function.
4131 */
4132 struct PrintfArguments {
4133   int nArg;                /* Total number of arguments */
4134   int nUsed;               /* Number of arguments used so far */
4135   sqlite3_value **apArg;   /* The argument values */
4136 };
4137 
4138 char *sqlite3MPrintf(sqlite3*,const char*, ...);
4139 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
4140 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
4141   void sqlite3DebugPrintf(const char*, ...);
4142 #endif
4143 #if defined(SQLITE_TEST)
4144   void *sqlite3TestTextToPtr(const char*);
4145 #endif
4146 
4147 #if defined(SQLITE_DEBUG)
4148   void sqlite3TreeViewExpr(TreeView*, const Expr*, u8);
4149   void sqlite3TreeViewBareExprList(TreeView*, const ExprList*, const char*);
4150   void sqlite3TreeViewExprList(TreeView*, const ExprList*, u8, const char*);
4151   void sqlite3TreeViewSrcList(TreeView*, const SrcList*);
4152   void sqlite3TreeViewSelect(TreeView*, const Select*, u8);
4153   void sqlite3TreeViewWith(TreeView*, const With*, u8);
4154 #ifndef SQLITE_OMIT_WINDOWFUNC
4155   void sqlite3TreeViewWindow(TreeView*, const Window*, u8);
4156   void sqlite3TreeViewWinFunc(TreeView*, const Window*, u8);
4157 #endif
4158 #endif
4159 
4160 
4161 void sqlite3SetString(char **, sqlite3*, const char*);
4162 void sqlite3ErrorMsg(Parse*, const char*, ...);
4163 int sqlite3ErrorToParser(sqlite3*,int);
4164 void sqlite3Dequote(char*);
4165 void sqlite3DequoteExpr(Expr*);
4166 void sqlite3TokenInit(Token*,char*);
4167 int sqlite3KeywordCode(const unsigned char*, int);
4168 int sqlite3RunParser(Parse*, const char*, char **);
4169 void sqlite3FinishCoding(Parse*);
4170 int sqlite3GetTempReg(Parse*);
4171 void sqlite3ReleaseTempReg(Parse*,int);
4172 int sqlite3GetTempRange(Parse*,int);
4173 void sqlite3ReleaseTempRange(Parse*,int,int);
4174 void sqlite3ClearTempRegCache(Parse*);
4175 #ifdef SQLITE_DEBUG
4176 int sqlite3NoTempsInRange(Parse*,int,int);
4177 #endif
4178 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
4179 Expr *sqlite3Expr(sqlite3*,int,const char*);
4180 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
4181 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*);
4182 void sqlite3PExprAddSelect(Parse*, Expr*, Select*);
4183 Expr *sqlite3ExprAnd(Parse*,Expr*, Expr*);
4184 Expr *sqlite3ExprSimplifiedAndOr(Expr*);
4185 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*, int);
4186 void sqlite3ExprFunctionUsable(Parse*,Expr*,FuncDef*);
4187 void sqlite3ExprAssignVarNumber(Parse*, Expr*, u32);
4188 void sqlite3ExprDelete(sqlite3*, Expr*);
4189 void sqlite3ExprUnmapAndDelete(Parse*, Expr*);
4190 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
4191 ExprList *sqlite3ExprListAppendVector(Parse*,ExprList*,IdList*,Expr*);
4192 void sqlite3ExprListSetSortOrder(ExprList*,int,int);
4193 void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
4194 void sqlite3ExprListSetSpan(Parse*,ExprList*,const char*,const char*);
4195 void sqlite3ExprListDelete(sqlite3*, ExprList*);
4196 u32 sqlite3ExprListFlags(const ExprList*);
4197 int sqlite3IndexHasDuplicateRootPage(Index*);
4198 int sqlite3Init(sqlite3*, char**);
4199 int sqlite3InitCallback(void*, int, char**, char**);
4200 int sqlite3InitOne(sqlite3*, int, char**, u32);
4201 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
4202 #ifndef SQLITE_OMIT_VIRTUALTABLE
4203 Module *sqlite3PragmaVtabRegister(sqlite3*,const char *zName);
4204 #endif
4205 void sqlite3ResetAllSchemasOfConnection(sqlite3*);
4206 void sqlite3ResetOneSchema(sqlite3*,int);
4207 void sqlite3CollapseDatabaseArray(sqlite3*);
4208 void sqlite3CommitInternalChanges(sqlite3*);
4209 void sqlite3DeleteColumnNames(sqlite3*,Table*);
4210 int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
4211 void sqlite3SelectAddColumnTypeAndCollation(Parse*,Table*,Select*,char);
4212 Table *sqlite3ResultSetOfSelect(Parse*,Select*,char);
4213 void sqlite3OpenSchemaTable(Parse *, int);
4214 Index *sqlite3PrimaryKeyIndex(Table*);
4215 i16 sqlite3TableColumnToIndex(Index*, i16);
4216 #ifdef SQLITE_OMIT_GENERATED_COLUMNS
4217 # define sqlite3TableColumnToStorage(T,X) (X)  /* No-op pass-through */
4218 # define sqlite3StorageColumnToTable(T,X) (X)  /* No-op pass-through */
4219 #else
4220   i16 sqlite3TableColumnToStorage(Table*, i16);
4221   i16 sqlite3StorageColumnToTable(Table*, i16);
4222 #endif
4223 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
4224 #if SQLITE_ENABLE_HIDDEN_COLUMNS
4225   void sqlite3ColumnPropertiesFromName(Table*, Column*);
4226 #else
4227 # define sqlite3ColumnPropertiesFromName(T,C) /* no-op */
4228 #endif
4229 void sqlite3AddColumn(Parse*,Token*,Token*);
4230 void sqlite3AddNotNull(Parse*, int);
4231 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
4232 void sqlite3AddCheckConstraint(Parse*, Expr*, const char*, const char*);
4233 void sqlite3AddDefaultValue(Parse*,Expr*,const char*,const char*);
4234 void sqlite3AddCollateType(Parse*, Token*);
4235 void sqlite3AddGenerated(Parse*,Expr*,Token*);
4236 void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
4237 int sqlite3ParseUri(const char*,const char*,unsigned int*,
4238                     sqlite3_vfs**,char**,char **);
4239 #define sqlite3CodecQueryParameters(A,B,C) 0
4240 Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
4241 
4242 #ifdef SQLITE_UNTESTABLE
4243 # define sqlite3FaultSim(X) SQLITE_OK
4244 #else
4245   int sqlite3FaultSim(int);
4246 #endif
4247 
4248 Bitvec *sqlite3BitvecCreate(u32);
4249 int sqlite3BitvecTest(Bitvec*, u32);
4250 int sqlite3BitvecTestNotNull(Bitvec*, u32);
4251 int sqlite3BitvecSet(Bitvec*, u32);
4252 void sqlite3BitvecClear(Bitvec*, u32, void*);
4253 void sqlite3BitvecDestroy(Bitvec*);
4254 u32 sqlite3BitvecSize(Bitvec*);
4255 #ifndef SQLITE_UNTESTABLE
4256 int sqlite3BitvecBuiltinTest(int,int*);
4257 #endif
4258 
4259 RowSet *sqlite3RowSetInit(sqlite3*);
4260 void sqlite3RowSetDelete(void*);
4261 void sqlite3RowSetClear(void*);
4262 void sqlite3RowSetInsert(RowSet*, i64);
4263 int sqlite3RowSetTest(RowSet*, int iBatch, i64);
4264 int sqlite3RowSetNext(RowSet*, i64*);
4265 
4266 void sqlite3CreateView(Parse*,Token*,Token*,Token*,ExprList*,Select*,int,int);
4267 
4268 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
4269   int sqlite3ViewGetColumnNames(Parse*,Table*);
4270 #else
4271 # define sqlite3ViewGetColumnNames(A,B) 0
4272 #endif
4273 
4274 #if SQLITE_MAX_ATTACHED>30
4275   int sqlite3DbMaskAllZero(yDbMask);
4276 #endif
4277 void sqlite3DropTable(Parse*, SrcList*, int, int);
4278 void sqlite3CodeDropTable(Parse*, Table*, int, int);
4279 void sqlite3DeleteTable(sqlite3*, Table*);
4280 void sqlite3FreeIndex(sqlite3*, Index*);
4281 #ifndef SQLITE_OMIT_AUTOINCREMENT
4282   void sqlite3AutoincrementBegin(Parse *pParse);
4283   void sqlite3AutoincrementEnd(Parse *pParse);
4284 #else
4285 # define sqlite3AutoincrementBegin(X)
4286 # define sqlite3AutoincrementEnd(X)
4287 #endif
4288 void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int, Upsert*);
4289 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
4290   void sqlite3ComputeGeneratedColumns(Parse*, int, Table*);
4291 #endif
4292 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
4293 IdList *sqlite3IdListAppend(Parse*, IdList*, Token*);
4294 int sqlite3IdListIndex(IdList*,const char*);
4295 SrcList *sqlite3SrcListEnlarge(Parse*, SrcList*, int, int);
4296 SrcList *sqlite3SrcListAppendList(Parse *pParse, SrcList *p1, SrcList *p2);
4297 SrcList *sqlite3SrcListAppend(Parse*, SrcList*, Token*, Token*);
4298 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
4299                                       Token*, Select*, Expr*, IdList*);
4300 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
4301 void sqlite3SrcListFuncArgs(Parse*, SrcList*, ExprList*);
4302 int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
4303 void sqlite3SrcListShiftJoinType(SrcList*);
4304 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
4305 void sqlite3IdListDelete(sqlite3*, IdList*);
4306 void sqlite3SrcListDelete(sqlite3*, SrcList*);
4307 Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
4308 void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
4309                           Expr*, int, int, u8);
4310 void sqlite3DropIndex(Parse*, SrcList*, int);
4311 int sqlite3Select(Parse*, Select*, SelectDest*);
4312 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
4313                          Expr*,ExprList*,u32,Expr*);
4314 void sqlite3SelectDelete(sqlite3*, Select*);
4315 Table *sqlite3SrcListLookup(Parse*, SrcList*);
4316 int sqlite3IsReadOnly(Parse*, Table*, int);
4317 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
4318 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
4319 Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,char*);
4320 #endif
4321 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*, ExprList*, Expr*);
4322 void sqlite3Update(Parse*, SrcList*, ExprList*,Expr*,int,ExprList*,Expr*,
4323                    Upsert*);
4324 WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
4325 void sqlite3WhereEnd(WhereInfo*);
4326 LogEst sqlite3WhereOutputRowCount(WhereInfo*);
4327 int sqlite3WhereIsDistinct(WhereInfo*);
4328 int sqlite3WhereIsOrdered(WhereInfo*);
4329 int sqlite3WhereOrderByLimitOptLabel(WhereInfo*);
4330 int sqlite3WhereIsSorted(WhereInfo*);
4331 int sqlite3WhereContinueLabel(WhereInfo*);
4332 int sqlite3WhereBreakLabel(WhereInfo*);
4333 int sqlite3WhereOkOnePass(WhereInfo*, int*);
4334 #define ONEPASS_OFF      0        /* Use of ONEPASS not allowed */
4335 #define ONEPASS_SINGLE   1        /* ONEPASS valid for a single row update */
4336 #define ONEPASS_MULTI    2        /* ONEPASS is valid for multiple rows */
4337 int sqlite3WhereUsesDeferredSeek(WhereInfo*);
4338 void sqlite3ExprCodeLoadIndexColumn(Parse*, Index*, int, int, int);
4339 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
4340 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
4341 void sqlite3ExprCodeMove(Parse*, int, int, int);
4342 void sqlite3ExprCode(Parse*, Expr*, int);
4343 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
4344 void sqlite3ExprCodeGeneratedColumn(Parse*, Column*, int);
4345 #endif
4346 void sqlite3ExprCodeCopy(Parse*, Expr*, int);
4347 void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
4348 int sqlite3ExprCodeRunJustOnce(Parse*, Expr*, int);
4349 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
4350 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
4351 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int, u8);
4352 #define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
4353 #define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
4354 #define SQLITE_ECEL_REF      0x04  /* Use ExprList.u.x.iOrderByCol */
4355 #define SQLITE_ECEL_OMITREF  0x08  /* Omit if ExprList.u.x.iOrderByCol */
4356 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
4357 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
4358 void sqlite3ExprIfFalseDup(Parse*, Expr*, int, int);
4359 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
4360 #define LOCATE_VIEW    0x01
4361 #define LOCATE_NOERR   0x02
4362 Table *sqlite3LocateTable(Parse*,u32 flags,const char*, const char*);
4363 Table *sqlite3LocateTableItem(Parse*,u32 flags,struct SrcList_item *);
4364 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
4365 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
4366 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
4367 void sqlite3Vacuum(Parse*,Token*,Expr*);
4368 int sqlite3RunVacuum(char**, sqlite3*, int, sqlite3_value*);
4369 char *sqlite3NameFromToken(sqlite3*, Token*);
4370 int sqlite3ExprCompare(Parse*,Expr*, Expr*, int);
4371 int sqlite3ExprCompareSkip(Expr*, Expr*, int);
4372 int sqlite3ExprListCompare(ExprList*, ExprList*, int);
4373 int sqlite3ExprImpliesExpr(Parse*,Expr*, Expr*, int);
4374 int sqlite3ExprImpliesNonNullRow(Expr*,int);
4375 void sqlite3AggInfoPersistWalkerInit(Walker*,Parse*);
4376 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
4377 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
4378 int sqlite3ExprCoveredByIndex(Expr*, int iCur, Index *pIdx);
4379 int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
4380 Vdbe *sqlite3GetVdbe(Parse*);
4381 #ifndef SQLITE_UNTESTABLE
4382 void sqlite3PrngSaveState(void);
4383 void sqlite3PrngRestoreState(void);
4384 #endif
4385 void sqlite3RollbackAll(sqlite3*,int);
4386 void sqlite3CodeVerifySchema(Parse*, int);
4387 void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
4388 void sqlite3BeginTransaction(Parse*, int);
4389 void sqlite3EndTransaction(Parse*,int);
4390 void sqlite3Savepoint(Parse*, int, Token*);
4391 void sqlite3CloseSavepoints(sqlite3 *);
4392 void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
4393 u32 sqlite3IsTrueOrFalse(const char*);
4394 int sqlite3ExprIdToTrueFalse(Expr*);
4395 int sqlite3ExprTruthValue(const Expr*);
4396 int sqlite3ExprIsConstant(Expr*);
4397 int sqlite3ExprIsConstantNotJoin(Expr*);
4398 int sqlite3ExprIsConstantOrFunction(Expr*, u8);
4399 int sqlite3ExprIsConstantOrGroupBy(Parse*, Expr*, ExprList*);
4400 int sqlite3ExprIsTableConstant(Expr*,int);
4401 #ifdef SQLITE_ENABLE_CURSOR_HINTS
4402 int sqlite3ExprContainsSubquery(Expr*);
4403 #endif
4404 int sqlite3ExprIsInteger(Expr*, int*);
4405 int sqlite3ExprCanBeNull(const Expr*);
4406 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
4407 int sqlite3IsRowid(const char*);
4408 void sqlite3GenerateRowDelete(
4409     Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8,int);
4410 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*, int);
4411 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
4412 void sqlite3ResolvePartIdxLabel(Parse*,int);
4413 int sqlite3ExprReferencesUpdatedColumn(Expr*,int*,int);
4414 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
4415                                      u8,u8,int,int*,int*,Upsert*);
4416 #ifdef SQLITE_ENABLE_NULL_TRIM
4417   void sqlite3SetMakeRecordP5(Vdbe*,Table*);
4418 #else
4419 # define sqlite3SetMakeRecordP5(A,B)
4420 #endif
4421 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
4422 int sqlite3OpenTableAndIndices(Parse*, Table*, int, u8, int, u8*, int*, int*);
4423 void sqlite3BeginWriteOperation(Parse*, int, int);
4424 void sqlite3MultiWrite(Parse*);
4425 void sqlite3MayAbort(Parse*);
4426 void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
4427 void sqlite3UniqueConstraint(Parse*, int, Index*);
4428 void sqlite3RowidConstraint(Parse*, int, Table*);
4429 Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
4430 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
4431 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
4432 IdList *sqlite3IdListDup(sqlite3*,IdList*);
4433 Select *sqlite3SelectDup(sqlite3*,Select*,int);
4434 FuncDef *sqlite3FunctionSearch(int,const char*);
4435 void sqlite3InsertBuiltinFuncs(FuncDef*,int);
4436 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,u8,u8);
4437 void sqlite3RegisterBuiltinFunctions(void);
4438 void sqlite3RegisterDateTimeFunctions(void);
4439 void sqlite3RegisterPerConnectionBuiltinFunctions(sqlite3*);
4440 int sqlite3SafetyCheckOk(sqlite3*);
4441 int sqlite3SafetyCheckSickOrOk(sqlite3*);
4442 void sqlite3ChangeCookie(Parse*, int);
4443 
4444 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
4445 void sqlite3MaterializeView(Parse*, Table*, Expr*, ExprList*,Expr*,int);
4446 #endif
4447 
4448 #ifndef SQLITE_OMIT_TRIGGER
4449   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
4450                            Expr*,int, int);
4451   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
4452   void sqlite3DropTrigger(Parse*, SrcList*, int);
4453   void sqlite3DropTriggerPtr(Parse*, Trigger*);
4454   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
4455   Trigger *sqlite3TriggerList(Parse *, Table *);
4456   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
4457                             int, int, int);
4458   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
4459   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
4460   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
4461   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*,
4462                                         const char*,const char*);
4463   TriggerStep *sqlite3TriggerInsertStep(Parse*,Token*, IdList*,
4464                                         Select*,u8,Upsert*,
4465                                         const char*,const char*);
4466   TriggerStep *sqlite3TriggerUpdateStep(Parse*,Token*,SrcList*,ExprList*,
4467                                         Expr*, u8, const char*,const char*);
4468   TriggerStep *sqlite3TriggerDeleteStep(Parse*,Token*, Expr*,
4469                                         const char*,const char*);
4470   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
4471   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
4472   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
4473   SrcList *sqlite3TriggerStepSrc(Parse*, TriggerStep*);
4474 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
4475 # define sqlite3IsToplevel(p) ((p)->pToplevel==0)
4476 #else
4477 # define sqlite3TriggersExist(B,C,D,E,F) 0
4478 # define sqlite3DeleteTrigger(A,B)
4479 # define sqlite3DropTriggerPtr(A,B)
4480 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
4481 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
4482 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
4483 # define sqlite3TriggerList(X, Y) 0
4484 # define sqlite3ParseToplevel(p) p
4485 # define sqlite3IsToplevel(p) 1
4486 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
4487 # define sqlite3TriggerStepSrc(A,B) 0
4488 #endif
4489 
4490 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
4491 void sqlite3SetJoinExpr(Expr*,int);
4492 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
4493 void sqlite3DeferForeignKey(Parse*, int);
4494 #ifndef SQLITE_OMIT_AUTHORIZATION
4495   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
4496   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
4497   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
4498   void sqlite3AuthContextPop(AuthContext*);
4499   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
4500 #else
4501 # define sqlite3AuthRead(a,b,c,d)
4502 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
4503 # define sqlite3AuthContextPush(a,b,c)
4504 # define sqlite3AuthContextPop(a)  ((void)(a))
4505 #endif
4506 int sqlite3DbIsNamed(sqlite3 *db, int iDb, const char *zName);
4507 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
4508 void sqlite3Detach(Parse*, Expr*);
4509 void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
4510 int sqlite3FixSrcList(DbFixer*, SrcList*);
4511 int sqlite3FixSelect(DbFixer*, Select*);
4512 int sqlite3FixExpr(DbFixer*, Expr*);
4513 int sqlite3FixExprList(DbFixer*, ExprList*);
4514 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
4515 int sqlite3RealSameAsInt(double,sqlite3_int64);
4516 void sqlite3Int64ToText(i64,char*);
4517 int sqlite3AtoF(const char *z, double*, int, u8);
4518 int sqlite3GetInt32(const char *, int*);
4519 int sqlite3GetUInt32(const char*, u32*);
4520 int sqlite3Atoi(const char*);
4521 #ifndef SQLITE_OMIT_UTF16
4522 int sqlite3Utf16ByteLen(const void *pData, int nChar);
4523 #endif
4524 int sqlite3Utf8CharLen(const char *pData, int nByte);
4525 u32 sqlite3Utf8Read(const u8**);
4526 LogEst sqlite3LogEst(u64);
4527 LogEst sqlite3LogEstAdd(LogEst,LogEst);
4528 #ifndef SQLITE_OMIT_VIRTUALTABLE
4529 LogEst sqlite3LogEstFromDouble(double);
4530 #endif
4531 #if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \
4532     defined(SQLITE_ENABLE_STAT4) || \
4533     defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
4534 u64 sqlite3LogEstToInt(LogEst);
4535 #endif
4536 VList *sqlite3VListAdd(sqlite3*,VList*,const char*,int,int);
4537 const char *sqlite3VListNumToName(VList*,int);
4538 int sqlite3VListNameToNum(VList*,const char*,int);
4539 
4540 /*
4541 ** Routines to read and write variable-length integers.  These used to
4542 ** be defined locally, but now we use the varint routines in the util.c
4543 ** file.
4544 */
4545 int sqlite3PutVarint(unsigned char*, u64);
4546 u8 sqlite3GetVarint(const unsigned char *, u64 *);
4547 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
4548 int sqlite3VarintLen(u64 v);
4549 
4550 /*
4551 ** The common case is for a varint to be a single byte.  They following
4552 ** macros handle the common case without a procedure call, but then call
4553 ** the procedure for larger varints.
4554 */
4555 #define getVarint32(A,B)  \
4556   (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
4557 #define getVarint32NR(A,B) \
4558   B=(u32)*(A);if(B>=0x80)sqlite3GetVarint32((A),(u32*)&(B))
4559 #define putVarint32(A,B)  \
4560   (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
4561   sqlite3PutVarint((A),(B)))
4562 #define getVarint    sqlite3GetVarint
4563 #define putVarint    sqlite3PutVarint
4564 
4565 
4566 const char *sqlite3IndexAffinityStr(sqlite3*, Index*);
4567 void sqlite3TableAffinity(Vdbe*, Table*, int);
4568 char sqlite3CompareAffinity(const Expr *pExpr, char aff2);
4569 int sqlite3IndexAffinityOk(const Expr *pExpr, char idx_affinity);
4570 char sqlite3TableColumnAffinity(Table*,int);
4571 char sqlite3ExprAffinity(const Expr *pExpr);
4572 int sqlite3Atoi64(const char*, i64*, int, u8);
4573 int sqlite3DecOrHexToI64(const char*, i64*);
4574 void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
4575 void sqlite3Error(sqlite3*,int);
4576 void sqlite3SystemError(sqlite3*,int);
4577 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
4578 u8 sqlite3HexToInt(int h);
4579 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
4580 
4581 #if defined(SQLITE_NEED_ERR_NAME)
4582 const char *sqlite3ErrName(int);
4583 #endif
4584 
4585 #ifdef SQLITE_ENABLE_DESERIALIZE
4586 int sqlite3MemdbInit(void);
4587 #endif
4588 
4589 const char *sqlite3ErrStr(int);
4590 int sqlite3ReadSchema(Parse *pParse);
4591 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
4592 int sqlite3IsBinary(const CollSeq*);
4593 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
4594 void sqlite3SetTextEncoding(sqlite3 *db, u8);
4595 CollSeq *sqlite3ExprCollSeq(Parse *pParse, const Expr *pExpr);
4596 CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, const Expr *pExpr);
4597 int sqlite3ExprCollSeqMatch(Parse*,const Expr*,const Expr*);
4598 Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*, int);
4599 Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
4600 Expr *sqlite3ExprSkipCollate(Expr*);
4601 Expr *sqlite3ExprSkipCollateAndLikely(Expr*);
4602 int sqlite3CheckCollSeq(Parse *, CollSeq *);
4603 int sqlite3WritableSchema(sqlite3*);
4604 int sqlite3CheckObjectName(Parse*, const char*,const char*,const char*);
4605 void sqlite3VdbeSetChanges(sqlite3 *, int);
4606 int sqlite3AddInt64(i64*,i64);
4607 int sqlite3SubInt64(i64*,i64);
4608 int sqlite3MulInt64(i64*,i64);
4609 int sqlite3AbsInt32(int);
4610 #ifdef SQLITE_ENABLE_8_3_NAMES
4611 void sqlite3FileSuffix3(const char*, char*);
4612 #else
4613 # define sqlite3FileSuffix3(X,Y)
4614 #endif
4615 u8 sqlite3GetBoolean(const char *z,u8);
4616 
4617 const void *sqlite3ValueText(sqlite3_value*, u8);
4618 int sqlite3ValueBytes(sqlite3_value*, u8);
4619 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
4620                         void(*)(void*));
4621 void sqlite3ValueSetNull(sqlite3_value*);
4622 void sqlite3ValueFree(sqlite3_value*);
4623 #ifndef SQLITE_UNTESTABLE
4624 void sqlite3ResultIntReal(sqlite3_context*);
4625 #endif
4626 sqlite3_value *sqlite3ValueNew(sqlite3 *);
4627 #ifndef SQLITE_OMIT_UTF16
4628 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
4629 #endif
4630 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
4631 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
4632 #ifndef SQLITE_AMALGAMATION
4633 extern const unsigned char sqlite3OpcodeProperty[];
4634 extern const char sqlite3StrBINARY[];
4635 extern const unsigned char sqlite3UpperToLower[];
4636 extern const unsigned char sqlite3CtypeMap[];
4637 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
4638 extern FuncDefHash sqlite3BuiltinFunctions;
4639 #ifndef SQLITE_OMIT_WSD
4640 extern int sqlite3PendingByte;
4641 #endif
4642 #endif /* SQLITE_AMALGAMATION */
4643 #ifdef VDBE_PROFILE
4644 extern sqlite3_uint64 sqlite3NProfileCnt;
4645 #endif
4646 void sqlite3RootPageMoved(sqlite3*, int, Pgno, Pgno);
4647 void sqlite3Reindex(Parse*, Token*, Token*);
4648 void sqlite3AlterFunctions(void);
4649 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
4650 void sqlite3AlterRenameColumn(Parse*, SrcList*, Token*, Token*);
4651 int sqlite3GetToken(const unsigned char *, int *);
4652 void sqlite3NestedParse(Parse*, const char*, ...);
4653 void sqlite3ExpirePreparedStatements(sqlite3*, int);
4654 void sqlite3CodeRhsOfIN(Parse*, Expr*, int);
4655 int sqlite3CodeSubselect(Parse*, Expr*);
4656 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
4657 int sqlite3ExpandSubquery(Parse*, struct SrcList_item*);
4658 void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
4659 int sqlite3MatchEName(
4660   const struct ExprList_item*,
4661   const char*,
4662   const char*,
4663   const char*
4664 );
4665 Bitmask sqlite3ExprColUsed(Expr*);
4666 u8 sqlite3StrIHash(const char*);
4667 int sqlite3ResolveExprNames(NameContext*, Expr*);
4668 int sqlite3ResolveExprListNames(NameContext*, ExprList*);
4669 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
4670 int sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
4671 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
4672 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
4673 void sqlite3AlterFinishAddColumn(Parse *, Token *);
4674 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
4675 void *sqlite3RenameTokenMap(Parse*, void*, Token*);
4676 void sqlite3RenameTokenRemap(Parse*, void *pTo, void *pFrom);
4677 void sqlite3RenameExprUnmap(Parse*, Expr*);
4678 void sqlite3RenameExprlistUnmap(Parse*, ExprList*);
4679 CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
4680 char sqlite3AffinityType(const char*, Column*);
4681 void sqlite3Analyze(Parse*, Token*, Token*);
4682 int sqlite3InvokeBusyHandler(BusyHandler*);
4683 int sqlite3FindDb(sqlite3*, Token*);
4684 int sqlite3FindDbName(sqlite3 *, const char *);
4685 int sqlite3AnalysisLoad(sqlite3*,int iDB);
4686 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
4687 void sqlite3DefaultRowEst(Index*);
4688 void sqlite3RegisterLikeFunctions(sqlite3*, int);
4689 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
4690 void sqlite3SchemaClear(void *);
4691 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
4692 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
4693 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
4694 void sqlite3KeyInfoUnref(KeyInfo*);
4695 KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
4696 KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
4697 KeyInfo *sqlite3KeyInfoFromExprList(Parse*, ExprList*, int, int);
4698 int sqlite3HasExplicitNulls(Parse*, ExprList*);
4699 
4700 #ifdef SQLITE_DEBUG
4701 int sqlite3KeyInfoIsWriteable(KeyInfo*);
4702 #endif
4703 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
4704   void (*)(sqlite3_context*,int,sqlite3_value **),
4705   void (*)(sqlite3_context*,int,sqlite3_value **),
4706   void (*)(sqlite3_context*),
4707   void (*)(sqlite3_context*),
4708   void (*)(sqlite3_context*,int,sqlite3_value **),
4709   FuncDestructor *pDestructor
4710 );
4711 void sqlite3NoopDestructor(void*);
4712 void sqlite3OomFault(sqlite3*);
4713 void sqlite3OomClear(sqlite3*);
4714 int sqlite3ApiExit(sqlite3 *db, int);
4715 int sqlite3OpenTempDatabase(Parse *);
4716 
4717 void sqlite3StrAccumInit(StrAccum*, sqlite3*, char*, int, int);
4718 char *sqlite3StrAccumFinish(StrAccum*);
4719 void sqlite3SelectDestInit(SelectDest*,int,int);
4720 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
4721 
4722 void sqlite3BackupRestart(sqlite3_backup *);
4723 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
4724 
4725 #ifndef SQLITE_OMIT_SUBQUERY
4726 int sqlite3ExprCheckIN(Parse*, Expr*);
4727 #else
4728 # define sqlite3ExprCheckIN(x,y) SQLITE_OK
4729 #endif
4730 
4731 #ifdef SQLITE_ENABLE_STAT4
4732 int sqlite3Stat4ProbeSetValue(
4733     Parse*,Index*,UnpackedRecord**,Expr*,int,int,int*);
4734 int sqlite3Stat4ValueFromExpr(Parse*, Expr*, u8, sqlite3_value**);
4735 void sqlite3Stat4ProbeFree(UnpackedRecord*);
4736 int sqlite3Stat4Column(sqlite3*, const void*, int, int, sqlite3_value**);
4737 char sqlite3IndexColumnAffinity(sqlite3*, Index*, int);
4738 #endif
4739 
4740 /*
4741 ** The interface to the LEMON-generated parser
4742 */
4743 #ifndef SQLITE_AMALGAMATION
4744   void *sqlite3ParserAlloc(void*(*)(u64), Parse*);
4745   void sqlite3ParserFree(void*, void(*)(void*));
4746 #endif
4747 void sqlite3Parser(void*, int, Token);
4748 int sqlite3ParserFallback(int);
4749 #ifdef YYTRACKMAXSTACKDEPTH
4750   int sqlite3ParserStackPeak(void*);
4751 #endif
4752 
4753 void sqlite3AutoLoadExtensions(sqlite3*);
4754 #ifndef SQLITE_OMIT_LOAD_EXTENSION
4755   void sqlite3CloseExtensions(sqlite3*);
4756 #else
4757 # define sqlite3CloseExtensions(X)
4758 #endif
4759 
4760 #ifndef SQLITE_OMIT_SHARED_CACHE
4761   void sqlite3TableLock(Parse *, int, Pgno, u8, const char *);
4762 #else
4763   #define sqlite3TableLock(v,w,x,y,z)
4764 #endif
4765 
4766 #ifdef SQLITE_TEST
4767   int sqlite3Utf8To8(unsigned char*);
4768 #endif
4769 
4770 #ifdef SQLITE_OMIT_VIRTUALTABLE
4771 #  define sqlite3VtabClear(Y)
4772 #  define sqlite3VtabSync(X,Y) SQLITE_OK
4773 #  define sqlite3VtabRollback(X)
4774 #  define sqlite3VtabCommit(X)
4775 #  define sqlite3VtabInSync(db) 0
4776 #  define sqlite3VtabLock(X)
4777 #  define sqlite3VtabUnlock(X)
4778 #  define sqlite3VtabModuleUnref(D,X)
4779 #  define sqlite3VtabUnlockList(X)
4780 #  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
4781 #  define sqlite3GetVTable(X,Y)  ((VTable*)0)
4782 #else
4783    void sqlite3VtabClear(sqlite3 *db, Table*);
4784    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
4785    int sqlite3VtabSync(sqlite3 *db, Vdbe*);
4786    int sqlite3VtabRollback(sqlite3 *db);
4787    int sqlite3VtabCommit(sqlite3 *db);
4788    void sqlite3VtabLock(VTable *);
4789    void sqlite3VtabUnlock(VTable *);
4790    void sqlite3VtabModuleUnref(sqlite3*,Module*);
4791    void sqlite3VtabUnlockList(sqlite3*);
4792    int sqlite3VtabSavepoint(sqlite3 *, int, int);
4793    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
4794    VTable *sqlite3GetVTable(sqlite3*, Table*);
4795    Module *sqlite3VtabCreateModule(
4796      sqlite3*,
4797      const char*,
4798      const sqlite3_module*,
4799      void*,
4800      void(*)(void*)
4801    );
4802 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
4803 #endif
4804 int sqlite3ReadOnlyShadowTables(sqlite3 *db);
4805 #ifndef SQLITE_OMIT_VIRTUALTABLE
4806   int sqlite3ShadowTableName(sqlite3 *db, const char *zName);
4807   int sqlite3IsShadowTableOf(sqlite3*,Table*,const char*);
4808 #else
4809 # define sqlite3ShadowTableName(A,B) 0
4810 # define sqlite3IsShadowTableOf(A,B,C) 0
4811 #endif
4812 int sqlite3VtabEponymousTableInit(Parse*,Module*);
4813 void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
4814 void sqlite3VtabMakeWritable(Parse*,Table*);
4815 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
4816 void sqlite3VtabFinishParse(Parse*, Token*);
4817 void sqlite3VtabArgInit(Parse*);
4818 void sqlite3VtabArgExtend(Parse*, Token*);
4819 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
4820 int sqlite3VtabCallConnect(Parse*, Table*);
4821 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
4822 int sqlite3VtabBegin(sqlite3 *, VTable *);
4823 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
4824 sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
4825 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
4826 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
4827 void sqlite3ParserReset(Parse*);
4828 #ifdef SQLITE_ENABLE_NORMALIZE
4829 char *sqlite3Normalize(Vdbe*, const char*);
4830 #endif
4831 int sqlite3Reprepare(Vdbe*);
4832 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
4833 CollSeq *sqlite3ExprCompareCollSeq(Parse*,const Expr*);
4834 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, const Expr*, const Expr*);
4835 int sqlite3TempInMemory(const sqlite3*);
4836 const char *sqlite3JournalModename(int);
4837 #ifndef SQLITE_OMIT_WAL
4838   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
4839   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
4840 #endif
4841 #ifndef SQLITE_OMIT_CTE
4842   With *sqlite3WithAdd(Parse*,With*,Token*,ExprList*,Select*);
4843   void sqlite3WithDelete(sqlite3*,With*);
4844   void sqlite3WithPush(Parse*, With*, u8);
4845 #else
4846 #define sqlite3WithPush(x,y,z)
4847 #define sqlite3WithDelete(x,y)
4848 #endif
4849 #ifndef SQLITE_OMIT_UPSERT
4850   Upsert *sqlite3UpsertNew(sqlite3*,ExprList*,Expr*,ExprList*,Expr*,Upsert*);
4851   void sqlite3UpsertDelete(sqlite3*,Upsert*);
4852   Upsert *sqlite3UpsertDup(sqlite3*,Upsert*);
4853   int sqlite3UpsertAnalyzeTarget(Parse*,SrcList*,Upsert*);
4854   void sqlite3UpsertDoUpdate(Parse*,Upsert*,Table*,Index*,int);
4855   Upsert *sqlite3UpsertOfIndex(Upsert*,Index*);
4856   int sqlite3UpsertNextIsIPK(Upsert*);
4857 #else
4858 #define sqlite3UpsertNew(u,v,w,x,y,z) ((Upsert*)0)
4859 #define sqlite3UpsertDelete(x,y)
4860 #define sqlite3UpsertDup(x,y)         ((Upsert*)0)
4861 #define sqlite3UpsertOfIndex(x,y)     ((Upsert*)0)
4862 #define sqlite3UpsertNextIsIPK(x)     0
4863 #endif
4864 
4865 
4866 /* Declarations for functions in fkey.c. All of these are replaced by
4867 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
4868 ** key functionality is available. If OMIT_TRIGGER is defined but
4869 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
4870 ** this case foreign keys are parsed, but no other functionality is
4871 ** provided (enforcement of FK constraints requires the triggers sub-system).
4872 */
4873 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
4874   void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
4875   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
4876   void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
4877   int sqlite3FkRequired(Parse*, Table*, int*, int);
4878   u32 sqlite3FkOldmask(Parse*, Table*);
4879   FKey *sqlite3FkReferences(Table *);
4880 #else
4881   #define sqlite3FkActions(a,b,c,d,e,f)
4882   #define sqlite3FkCheck(a,b,c,d,e,f)
4883   #define sqlite3FkDropTable(a,b,c)
4884   #define sqlite3FkOldmask(a,b)         0
4885   #define sqlite3FkRequired(a,b,c,d)    0
4886   #define sqlite3FkReferences(a)        0
4887 #endif
4888 #ifndef SQLITE_OMIT_FOREIGN_KEY
4889   void sqlite3FkDelete(sqlite3 *, Table*);
4890   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
4891 #else
4892   #define sqlite3FkDelete(a,b)
4893   #define sqlite3FkLocateIndex(a,b,c,d,e)
4894 #endif
4895 
4896 
4897 /*
4898 ** Available fault injectors.  Should be numbered beginning with 0.
4899 */
4900 #define SQLITE_FAULTINJECTOR_MALLOC     0
4901 #define SQLITE_FAULTINJECTOR_COUNT      1
4902 
4903 /*
4904 ** The interface to the code in fault.c used for identifying "benign"
4905 ** malloc failures. This is only present if SQLITE_UNTESTABLE
4906 ** is not defined.
4907 */
4908 #ifndef SQLITE_UNTESTABLE
4909   void sqlite3BeginBenignMalloc(void);
4910   void sqlite3EndBenignMalloc(void);
4911 #else
4912   #define sqlite3BeginBenignMalloc()
4913   #define sqlite3EndBenignMalloc()
4914 #endif
4915 
4916 /*
4917 ** Allowed return values from sqlite3FindInIndex()
4918 */
4919 #define IN_INDEX_ROWID        1   /* Search the rowid of the table */
4920 #define IN_INDEX_EPH          2   /* Search an ephemeral b-tree */
4921 #define IN_INDEX_INDEX_ASC    3   /* Existing index ASCENDING */
4922 #define IN_INDEX_INDEX_DESC   4   /* Existing index DESCENDING */
4923 #define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
4924 /*
4925 ** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
4926 */
4927 #define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
4928 #define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
4929 #define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
4930 int sqlite3FindInIndex(Parse *, Expr *, u32, int*, int*, int*);
4931 
4932 int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
4933 int sqlite3JournalSize(sqlite3_vfs *);
4934 #if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
4935  || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
4936   int sqlite3JournalCreate(sqlite3_file *);
4937 #endif
4938 
4939 int sqlite3JournalIsInMemory(sqlite3_file *p);
4940 void sqlite3MemJournalOpen(sqlite3_file *);
4941 
4942 void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p);
4943 #if SQLITE_MAX_EXPR_DEPTH>0
4944   int sqlite3SelectExprHeight(Select *);
4945   int sqlite3ExprCheckHeight(Parse*, int);
4946 #else
4947   #define sqlite3SelectExprHeight(x) 0
4948   #define sqlite3ExprCheckHeight(x,y)
4949 #endif
4950 
4951 u32 sqlite3Get4byte(const u8*);
4952 void sqlite3Put4byte(u8*, u32);
4953 
4954 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
4955   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
4956   void sqlite3ConnectionUnlocked(sqlite3 *db);
4957   void sqlite3ConnectionClosed(sqlite3 *db);
4958 #else
4959   #define sqlite3ConnectionBlocked(x,y)
4960   #define sqlite3ConnectionUnlocked(x)
4961   #define sqlite3ConnectionClosed(x)
4962 #endif
4963 
4964 #ifdef SQLITE_DEBUG
4965   void sqlite3ParserTrace(FILE*, char *);
4966 #endif
4967 #if defined(YYCOVERAGE)
4968   int sqlite3ParserCoverage(FILE*);
4969 #endif
4970 
4971 /*
4972 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
4973 ** sqlite3IoTrace is a pointer to a printf-like routine used to
4974 ** print I/O tracing messages.
4975 */
4976 #ifdef SQLITE_ENABLE_IOTRACE
4977 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
4978   void sqlite3VdbeIOTraceSql(Vdbe*);
4979 SQLITE_API SQLITE_EXTERN void (SQLITE_CDECL *sqlite3IoTrace)(const char*,...);
4980 #else
4981 # define IOTRACE(A)
4982 # define sqlite3VdbeIOTraceSql(X)
4983 #endif
4984 
4985 /*
4986 ** These routines are available for the mem2.c debugging memory allocator
4987 ** only.  They are used to verify that different "types" of memory
4988 ** allocations are properly tracked by the system.
4989 **
4990 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
4991 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
4992 ** a single bit set.
4993 **
4994 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
4995 ** argument match the type set by the previous sqlite3MemdebugSetType().
4996 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
4997 **
4998 ** sqlite3MemdebugNoType() returns true if none of the bits in its second
4999 ** argument match the type set by the previous sqlite3MemdebugSetType().
5000 **
5001 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
5002 ** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
5003 ** it might have been allocated by lookaside, except the allocation was
5004 ** too large or lookaside was already full.  It is important to verify
5005 ** that allocations that might have been satisfied by lookaside are not
5006 ** passed back to non-lookaside free() routines.  Asserts such as the
5007 ** example above are placed on the non-lookaside free() routines to verify
5008 ** this constraint.
5009 **
5010 ** All of this is no-op for a production build.  It only comes into
5011 ** play when the SQLITE_MEMDEBUG compile-time option is used.
5012 */
5013 #ifdef SQLITE_MEMDEBUG
5014   void sqlite3MemdebugSetType(void*,u8);
5015   int sqlite3MemdebugHasType(void*,u8);
5016   int sqlite3MemdebugNoType(void*,u8);
5017 #else
5018 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
5019 # define sqlite3MemdebugHasType(X,Y)  1
5020 # define sqlite3MemdebugNoType(X,Y)   1
5021 #endif
5022 #define MEMTYPE_HEAP       0x01  /* General heap allocations */
5023 #define MEMTYPE_LOOKASIDE  0x02  /* Heap that might have been lookaside */
5024 #define MEMTYPE_PCACHE     0x04  /* Page cache allocations */
5025 
5026 /*
5027 ** Threading interface
5028 */
5029 #if SQLITE_MAX_WORKER_THREADS>0
5030 int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
5031 int sqlite3ThreadJoin(SQLiteThread*, void**);
5032 #endif
5033 
5034 #if defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)
5035 int sqlite3DbpageRegister(sqlite3*);
5036 #endif
5037 #if defined(SQLITE_ENABLE_DBSTAT_VTAB) || defined(SQLITE_TEST)
5038 int sqlite3DbstatRegister(sqlite3*);
5039 #endif
5040 
5041 int sqlite3ExprVectorSize(Expr *pExpr);
5042 int sqlite3ExprIsVector(Expr *pExpr);
5043 Expr *sqlite3VectorFieldSubexpr(Expr*, int);
5044 Expr *sqlite3ExprForVectorField(Parse*,Expr*,int);
5045 void sqlite3VectorErrorMsg(Parse*, Expr*);
5046 
5047 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
5048 const char **sqlite3CompileOptions(int *pnOpt);
5049 #endif
5050 
5051 #endif /* SQLITEINT_H */
5052