xref: /sqlite-3.40.0/src/sqliteInt.h (revision eb48b062)
1 /*
2 ** 2001 September 15
3 **
4 ** The author disclaims copyright to this source code.  In place of
5 ** a legal notice, here is a blessing:
6 **
7 **    May you do good and not evil.
8 **    May you find forgiveness for yourself and forgive others.
9 **    May you share freely, never taking more than you give.
10 **
11 *************************************************************************
12 ** Internal interface definitions for SQLite.
13 **
14 */
15 #ifndef _SQLITEINT_H_
16 #define _SQLITEINT_H_
17 
18 /*
19 ** Include the header file used to customize the compiler options for MSVC.
20 ** This should be done first so that it can successfully prevent spurious
21 ** compiler warnings due to subsequent content in this file and other files
22 ** that are included by this file.
23 */
24 #include "msvc.h"
25 
26 /*
27 ** Special setup for VxWorks
28 */
29 #include "vxworks.h"
30 
31 /*
32 ** These #defines should enable >2GB file support on POSIX if the
33 ** underlying operating system supports it.  If the OS lacks
34 ** large file support, or if the OS is windows, these should be no-ops.
35 **
36 ** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
37 ** system #includes.  Hence, this block of code must be the very first
38 ** code in all source files.
39 **
40 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
41 ** on the compiler command line.  This is necessary if you are compiling
42 ** on a recent machine (ex: Red Hat 7.2) but you want your code to work
43 ** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
44 ** without this option, LFS is enable.  But LFS does not exist in the kernel
45 ** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
46 ** portability you should omit LFS.
47 **
48 ** The previous paragraph was written in 2005.  (This paragraph is written
49 ** on 2008-11-28.) These days, all Linux kernels support large files, so
50 ** you should probably leave LFS enabled.  But some embedded platforms might
51 ** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
52 **
53 ** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
54 */
55 #ifndef SQLITE_DISABLE_LFS
56 # define _LARGE_FILE       1
57 # ifndef _FILE_OFFSET_BITS
58 #   define _FILE_OFFSET_BITS 64
59 # endif
60 # define _LARGEFILE_SOURCE 1
61 #endif
62 
63 /* Needed for various definitions... */
64 #if defined(__GNUC__) && !defined(_GNU_SOURCE)
65 # define _GNU_SOURCE
66 #endif
67 
68 #if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
69 # define _BSD_SOURCE
70 #endif
71 
72 /*
73 ** For MinGW, check to see if we can include the header file containing its
74 ** version information, among other things.  Normally, this internal MinGW
75 ** header file would [only] be included automatically by other MinGW header
76 ** files; however, the contained version information is now required by this
77 ** header file to work around binary compatibility issues (see below) and
78 ** this is the only known way to reliably obtain it.  This entire #if block
79 ** would be completely unnecessary if there was any other way of detecting
80 ** MinGW via their preprocessor (e.g. if they customized their GCC to define
81 ** some MinGW-specific macros).  When compiling for MinGW, either the
82 ** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
83 ** defined; otherwise, detection of conditions specific to MinGW will be
84 ** disabled.
85 */
86 #if defined(_HAVE_MINGW_H)
87 # include "mingw.h"
88 #elif defined(_HAVE__MINGW_H)
89 # include "_mingw.h"
90 #endif
91 
92 /*
93 ** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
94 ** define is required to maintain binary compatibility with the MSVC runtime
95 ** library in use (e.g. for Windows XP).
96 */
97 #if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
98     defined(_WIN32) && !defined(_WIN64) && \
99     defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
100     defined(__MSVCRT__)
101 # define _USE_32BIT_TIME_T
102 #endif
103 
104 /* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
105 ** first in QNX.  Also, the _USE_32BIT_TIME_T macro must appear first for
106 ** MinGW.
107 */
108 #include "sqlite3.h"
109 
110 /*
111 ** Include the configuration header output by 'configure' if we're using the
112 ** autoconf-based build
113 */
114 #ifdef _HAVE_SQLITE_CONFIG_H
115 #include "config.h"
116 #endif
117 
118 #include "sqliteLimit.h"
119 
120 /* Disable nuisance warnings on Borland compilers */
121 #if defined(__BORLANDC__)
122 #pragma warn -rch /* unreachable code */
123 #pragma warn -ccc /* Condition is always true or false */
124 #pragma warn -aus /* Assigned value is never used */
125 #pragma warn -csu /* Comparing signed and unsigned */
126 #pragma warn -spa /* Suspicious pointer arithmetic */
127 #endif
128 
129 /*
130 ** Include standard header files as necessary
131 */
132 #ifdef HAVE_STDINT_H
133 #include <stdint.h>
134 #endif
135 #ifdef HAVE_INTTYPES_H
136 #include <inttypes.h>
137 #endif
138 
139 /*
140 ** The following macros are used to cast pointers to integers and
141 ** integers to pointers.  The way you do this varies from one compiler
142 ** to the next, so we have developed the following set of #if statements
143 ** to generate appropriate macros for a wide range of compilers.
144 **
145 ** The correct "ANSI" way to do this is to use the intptr_t type.
146 ** Unfortunately, that typedef is not available on all compilers, or
147 ** if it is available, it requires an #include of specific headers
148 ** that vary from one machine to the next.
149 **
150 ** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
151 ** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
152 ** So we have to define the macros in different ways depending on the
153 ** compiler.
154 */
155 #if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
156 # define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
157 # define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
158 #elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
159 # define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
160 # define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
161 #elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
162 # define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
163 # define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
164 #else                          /* Generates a warning - but it always works */
165 # define SQLITE_INT_TO_PTR(X)  ((void*)(X))
166 # define SQLITE_PTR_TO_INT(X)  ((int)(X))
167 #endif
168 
169 /*
170 ** A macro to hint to the compiler that a function should not be
171 ** inlined.
172 */
173 #if defined(__GNUC__)
174 #  define SQLITE_NOINLINE  __attribute__((noinline))
175 #elif defined(_MSC_VER) && _MSC_VER>=1310
176 #  define SQLITE_NOINLINE  __declspec(noinline)
177 #else
178 #  define SQLITE_NOINLINE
179 #endif
180 
181 /*
182 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
183 ** 0 means mutexes are permanently disable and the library is never
184 ** threadsafe.  1 means the library is serialized which is the highest
185 ** level of threadsafety.  2 means the library is multithreaded - multiple
186 ** threads can use SQLite as long as no two threads try to use the same
187 ** database connection at the same time.
188 **
189 ** Older versions of SQLite used an optional THREADSAFE macro.
190 ** We support that for legacy.
191 */
192 #if !defined(SQLITE_THREADSAFE)
193 # if defined(THREADSAFE)
194 #   define SQLITE_THREADSAFE THREADSAFE
195 # else
196 #   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
197 # endif
198 #endif
199 
200 /*
201 ** Powersafe overwrite is on by default.  But can be turned off using
202 ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
203 */
204 #ifndef SQLITE_POWERSAFE_OVERWRITE
205 # define SQLITE_POWERSAFE_OVERWRITE 1
206 #endif
207 
208 /*
209 ** EVIDENCE-OF: R-25715-37072 Memory allocation statistics are enabled by
210 ** default unless SQLite is compiled with SQLITE_DEFAULT_MEMSTATUS=0 in
211 ** which case memory allocation statistics are disabled by default.
212 */
213 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
214 # define SQLITE_DEFAULT_MEMSTATUS 1
215 #endif
216 
217 /*
218 ** Exactly one of the following macros must be defined in order to
219 ** specify which memory allocation subsystem to use.
220 **
221 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
222 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
223 **     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
224 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
225 **
226 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
227 ** assert() macro is enabled, each call into the Win32 native heap subsystem
228 ** will cause HeapValidate to be called.  If heap validation should fail, an
229 ** assertion will be triggered.
230 **
231 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
232 ** the default.
233 */
234 #if defined(SQLITE_SYSTEM_MALLOC) \
235   + defined(SQLITE_WIN32_MALLOC) \
236   + defined(SQLITE_ZERO_MALLOC) \
237   + defined(SQLITE_MEMDEBUG)>1
238 # error "Two or more of the following compile-time configuration options\
239  are defined but at most one is allowed:\
240  SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
241  SQLITE_ZERO_MALLOC"
242 #endif
243 #if defined(SQLITE_SYSTEM_MALLOC) \
244   + defined(SQLITE_WIN32_MALLOC) \
245   + defined(SQLITE_ZERO_MALLOC) \
246   + defined(SQLITE_MEMDEBUG)==0
247 # define SQLITE_SYSTEM_MALLOC 1
248 #endif
249 
250 /*
251 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
252 ** sizes of memory allocations below this value where possible.
253 */
254 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
255 # define SQLITE_MALLOC_SOFT_LIMIT 1024
256 #endif
257 
258 /*
259 ** We need to define _XOPEN_SOURCE as follows in order to enable
260 ** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
261 ** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
262 ** it.
263 */
264 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
265 #  define _XOPEN_SOURCE 600
266 #endif
267 
268 /*
269 ** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
270 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
271 ** make it true by defining or undefining NDEBUG.
272 **
273 ** Setting NDEBUG makes the code smaller and faster by disabling the
274 ** assert() statements in the code.  So we want the default action
275 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
276 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
277 ** feature.
278 */
279 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
280 # define NDEBUG 1
281 #endif
282 #if defined(NDEBUG) && defined(SQLITE_DEBUG)
283 # undef NDEBUG
284 #endif
285 
286 /*
287 ** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
288 */
289 #if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
290 # define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
291 #endif
292 
293 /*
294 ** The testcase() macro is used to aid in coverage testing.  When
295 ** doing coverage testing, the condition inside the argument to
296 ** testcase() must be evaluated both true and false in order to
297 ** get full branch coverage.  The testcase() macro is inserted
298 ** to help ensure adequate test coverage in places where simple
299 ** condition/decision coverage is inadequate.  For example, testcase()
300 ** can be used to make sure boundary values are tested.  For
301 ** bitmask tests, testcase() can be used to make sure each bit
302 ** is significant and used at least once.  On switch statements
303 ** where multiple cases go to the same block of code, testcase()
304 ** can insure that all cases are evaluated.
305 **
306 */
307 #ifdef SQLITE_COVERAGE_TEST
308   void sqlite3Coverage(int);
309 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
310 #else
311 # define testcase(X)
312 #endif
313 
314 /*
315 ** The TESTONLY macro is used to enclose variable declarations or
316 ** other bits of code that are needed to support the arguments
317 ** within testcase() and assert() macros.
318 */
319 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
320 # define TESTONLY(X)  X
321 #else
322 # define TESTONLY(X)
323 #endif
324 
325 /*
326 ** Sometimes we need a small amount of code such as a variable initialization
327 ** to setup for a later assert() statement.  We do not want this code to
328 ** appear when assert() is disabled.  The following macro is therefore
329 ** used to contain that setup code.  The "VVA" acronym stands for
330 ** "Verification, Validation, and Accreditation".  In other words, the
331 ** code within VVA_ONLY() will only run during verification processes.
332 */
333 #ifndef NDEBUG
334 # define VVA_ONLY(X)  X
335 #else
336 # define VVA_ONLY(X)
337 #endif
338 
339 /*
340 ** The ALWAYS and NEVER macros surround boolean expressions which
341 ** are intended to always be true or false, respectively.  Such
342 ** expressions could be omitted from the code completely.  But they
343 ** are included in a few cases in order to enhance the resilience
344 ** of SQLite to unexpected behavior - to make the code "self-healing"
345 ** or "ductile" rather than being "brittle" and crashing at the first
346 ** hint of unplanned behavior.
347 **
348 ** In other words, ALWAYS and NEVER are added for defensive code.
349 **
350 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
351 ** be true and false so that the unreachable code they specify will
352 ** not be counted as untested code.
353 */
354 #if defined(SQLITE_COVERAGE_TEST)
355 # define ALWAYS(X)      (1)
356 # define NEVER(X)       (0)
357 #elif !defined(NDEBUG)
358 # define ALWAYS(X)      ((X)?1:(assert(0),0))
359 # define NEVER(X)       ((X)?(assert(0),1):0)
360 #else
361 # define ALWAYS(X)      (X)
362 # define NEVER(X)       (X)
363 #endif
364 
365 /*
366 ** Return true (non-zero) if the input is an integer that is too large
367 ** to fit in 32-bits.  This macro is used inside of various testcase()
368 ** macros to verify that we have tested SQLite for large-file support.
369 */
370 #define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
371 
372 /*
373 ** The macro unlikely() is a hint that surrounds a boolean
374 ** expression that is usually false.  Macro likely() surrounds
375 ** a boolean expression that is usually true.  These hints could,
376 ** in theory, be used by the compiler to generate better code, but
377 ** currently they are just comments for human readers.
378 */
379 #define likely(X)    (X)
380 #define unlikely(X)  (X)
381 
382 #include "hash.h"
383 #include "parse.h"
384 #include <stdio.h>
385 #include <stdlib.h>
386 #include <string.h>
387 #include <assert.h>
388 #include <stddef.h>
389 
390 /*
391 ** If compiling for a processor that lacks floating point support,
392 ** substitute integer for floating-point
393 */
394 #ifdef SQLITE_OMIT_FLOATING_POINT
395 # define double sqlite_int64
396 # define float sqlite_int64
397 # define LONGDOUBLE_TYPE sqlite_int64
398 # ifndef SQLITE_BIG_DBL
399 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
400 # endif
401 # define SQLITE_OMIT_DATETIME_FUNCS 1
402 # define SQLITE_OMIT_TRACE 1
403 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
404 # undef SQLITE_HAVE_ISNAN
405 #endif
406 #ifndef SQLITE_BIG_DBL
407 # define SQLITE_BIG_DBL (1e99)
408 #endif
409 
410 /*
411 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
412 ** afterward. Having this macro allows us to cause the C compiler
413 ** to omit code used by TEMP tables without messy #ifndef statements.
414 */
415 #ifdef SQLITE_OMIT_TEMPDB
416 #define OMIT_TEMPDB 1
417 #else
418 #define OMIT_TEMPDB 0
419 #endif
420 
421 /*
422 ** The "file format" number is an integer that is incremented whenever
423 ** the VDBE-level file format changes.  The following macros define the
424 ** the default file format for new databases and the maximum file format
425 ** that the library can read.
426 */
427 #define SQLITE_MAX_FILE_FORMAT 4
428 #ifndef SQLITE_DEFAULT_FILE_FORMAT
429 # define SQLITE_DEFAULT_FILE_FORMAT 4
430 #endif
431 
432 /*
433 ** Determine whether triggers are recursive by default.  This can be
434 ** changed at run-time using a pragma.
435 */
436 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
437 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
438 #endif
439 
440 /*
441 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
442 ** on the command-line
443 */
444 #ifndef SQLITE_TEMP_STORE
445 # define SQLITE_TEMP_STORE 1
446 # define SQLITE_TEMP_STORE_xc 1  /* Exclude from ctime.c */
447 #endif
448 
449 /*
450 ** If no value has been provided for SQLITE_MAX_WORKER_THREADS, or if
451 ** SQLITE_TEMP_STORE is set to 3 (never use temporary files), set it
452 ** to zero.
453 */
454 #if SQLITE_TEMP_STORE==3 || SQLITE_THREADSAFE==0
455 # undef SQLITE_MAX_WORKER_THREADS
456 # define SQLITE_MAX_WORKER_THREADS 0
457 #endif
458 #ifndef SQLITE_MAX_WORKER_THREADS
459 # define SQLITE_MAX_WORKER_THREADS 8
460 #endif
461 #ifndef SQLITE_DEFAULT_WORKER_THREADS
462 # define SQLITE_DEFAULT_WORKER_THREADS 0
463 #endif
464 #if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
465 # undef SQLITE_MAX_WORKER_THREADS
466 # define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
467 #endif
468 
469 
470 /*
471 ** GCC does not define the offsetof() macro so we'll have to do it
472 ** ourselves.
473 */
474 #ifndef offsetof
475 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
476 #endif
477 
478 /*
479 ** Macros to compute minimum and maximum of two numbers.
480 */
481 #define MIN(A,B) ((A)<(B)?(A):(B))
482 #define MAX(A,B) ((A)>(B)?(A):(B))
483 
484 /*
485 ** Swap two objects of type TYPE.
486 */
487 #define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
488 
489 /*
490 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
491 ** not, there are still machines out there that use EBCDIC.)
492 */
493 #if 'A' == '\301'
494 # define SQLITE_EBCDIC 1
495 #else
496 # define SQLITE_ASCII 1
497 #endif
498 
499 /*
500 ** Integers of known sizes.  These typedefs might change for architectures
501 ** where the sizes very.  Preprocessor macros are available so that the
502 ** types can be conveniently redefined at compile-type.  Like this:
503 **
504 **         cc '-DUINTPTR_TYPE=long long int' ...
505 */
506 #ifndef UINT32_TYPE
507 # ifdef HAVE_UINT32_T
508 #  define UINT32_TYPE uint32_t
509 # else
510 #  define UINT32_TYPE unsigned int
511 # endif
512 #endif
513 #ifndef UINT16_TYPE
514 # ifdef HAVE_UINT16_T
515 #  define UINT16_TYPE uint16_t
516 # else
517 #  define UINT16_TYPE unsigned short int
518 # endif
519 #endif
520 #ifndef INT16_TYPE
521 # ifdef HAVE_INT16_T
522 #  define INT16_TYPE int16_t
523 # else
524 #  define INT16_TYPE short int
525 # endif
526 #endif
527 #ifndef UINT8_TYPE
528 # ifdef HAVE_UINT8_T
529 #  define UINT8_TYPE uint8_t
530 # else
531 #  define UINT8_TYPE unsigned char
532 # endif
533 #endif
534 #ifndef INT8_TYPE
535 # ifdef HAVE_INT8_T
536 #  define INT8_TYPE int8_t
537 # else
538 #  define INT8_TYPE signed char
539 # endif
540 #endif
541 #ifndef LONGDOUBLE_TYPE
542 # define LONGDOUBLE_TYPE long double
543 #endif
544 typedef sqlite_int64 i64;          /* 8-byte signed integer */
545 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
546 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
547 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
548 typedef INT16_TYPE i16;            /* 2-byte signed integer */
549 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
550 typedef INT8_TYPE i8;              /* 1-byte signed integer */
551 
552 /*
553 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
554 ** that can be stored in a u32 without loss of data.  The value
555 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
556 ** have to specify the value in the less intuitive manner shown:
557 */
558 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
559 
560 /*
561 ** The datatype used to store estimates of the number of rows in a
562 ** table or index.  This is an unsigned integer type.  For 99.9% of
563 ** the world, a 32-bit integer is sufficient.  But a 64-bit integer
564 ** can be used at compile-time if desired.
565 */
566 #ifdef SQLITE_64BIT_STATS
567  typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
568 #else
569  typedef u32 tRowcnt;    /* 32-bit is the default */
570 #endif
571 
572 /*
573 ** Estimated quantities used for query planning are stored as 16-bit
574 ** logarithms.  For quantity X, the value stored is 10*log2(X).  This
575 ** gives a possible range of values of approximately 1.0e986 to 1e-986.
576 ** But the allowed values are "grainy".  Not every value is representable.
577 ** For example, quantities 16 and 17 are both represented by a LogEst
578 ** of 40.  However, since LogEst quantities are suppose to be estimates,
579 ** not exact values, this imprecision is not a problem.
580 **
581 ** "LogEst" is short for "Logarithmic Estimate".
582 **
583 ** Examples:
584 **      1 -> 0              20 -> 43          10000 -> 132
585 **      2 -> 10             25 -> 46          25000 -> 146
586 **      3 -> 16            100 -> 66        1000000 -> 199
587 **      4 -> 20           1000 -> 99        1048576 -> 200
588 **     10 -> 33           1024 -> 100    4294967296 -> 320
589 **
590 ** The LogEst can be negative to indicate fractional values.
591 ** Examples:
592 **
593 **    0.5 -> -10           0.1 -> -33        0.0625 -> -40
594 */
595 typedef INT16_TYPE LogEst;
596 
597 /*
598 ** Set the SQLITE_PTRSIZE macro to the number of bytes in a pointer
599 */
600 #ifndef SQLITE_PTRSIZE
601 # if defined(__SIZEOF_POINTER__)
602 #   define SQLITE_PTRSIZE __SIZEOF_POINTER__
603 # elif defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
604        defined(_M_ARM)   || defined(__arm__)    || defined(__x86)
605 #   define SQLITE_PTRSIZE 4
606 # else
607 #   define SQLITE_PTRSIZE 8
608 # endif
609 #endif
610 
611 /*
612 ** Macros to determine whether the machine is big or little endian,
613 ** and whether or not that determination is run-time or compile-time.
614 **
615 ** For best performance, an attempt is made to guess at the byte-order
616 ** using C-preprocessor macros.  If that is unsuccessful, or if
617 ** -DSQLITE_RUNTIME_BYTEORDER=1 is set, then byte-order is determined
618 ** at run-time.
619 */
620 #ifdef SQLITE_AMALGAMATION
621 const int sqlite3one = 1;
622 #else
623 extern const int sqlite3one;
624 #endif
625 #if (defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
626      defined(__x86_64) || defined(__x86_64__) || defined(_M_X64)  ||    \
627      defined(_M_AMD64) || defined(_M_ARM)     || defined(__x86)   ||    \
628      defined(__arm__)) && !defined(SQLITE_RUNTIME_BYTEORDER)
629 # define SQLITE_BYTEORDER    1234
630 # define SQLITE_BIGENDIAN    0
631 # define SQLITE_LITTLEENDIAN 1
632 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
633 #endif
634 #if (defined(sparc)    || defined(__ppc__))  \
635     && !defined(SQLITE_RUNTIME_BYTEORDER)
636 # define SQLITE_BYTEORDER    4321
637 # define SQLITE_BIGENDIAN    1
638 # define SQLITE_LITTLEENDIAN 0
639 # define SQLITE_UTF16NATIVE  SQLITE_UTF16BE
640 #endif
641 #if !defined(SQLITE_BYTEORDER)
642 # define SQLITE_BYTEORDER    0     /* 0 means "unknown at compile-time" */
643 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
644 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
645 # define SQLITE_UTF16NATIVE  (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
646 #endif
647 
648 /*
649 ** Constants for the largest and smallest possible 64-bit signed integers.
650 ** These macros are designed to work correctly on both 32-bit and 64-bit
651 ** compilers.
652 */
653 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
654 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
655 
656 /*
657 ** Round up a number to the next larger multiple of 8.  This is used
658 ** to force 8-byte alignment on 64-bit architectures.
659 */
660 #define ROUND8(x)     (((x)+7)&~7)
661 
662 /*
663 ** Round down to the nearest multiple of 8
664 */
665 #define ROUNDDOWN8(x) ((x)&~7)
666 
667 /*
668 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
669 ** macro is used only within assert() to verify that the code gets
670 ** all alignment restrictions correct.
671 **
672 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
673 ** underlying malloc() implementation might return us 4-byte aligned
674 ** pointers.  In that case, only verify 4-byte alignment.
675 */
676 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
677 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
678 #else
679 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
680 #endif
681 
682 /*
683 ** Disable MMAP on platforms where it is known to not work
684 */
685 #if defined(__OpenBSD__) || defined(__QNXNTO__)
686 # undef SQLITE_MAX_MMAP_SIZE
687 # define SQLITE_MAX_MMAP_SIZE 0
688 #endif
689 
690 /*
691 ** Default maximum size of memory used by memory-mapped I/O in the VFS
692 */
693 #ifdef __APPLE__
694 # include <TargetConditionals.h>
695 # if TARGET_OS_IPHONE
696 #   undef SQLITE_MAX_MMAP_SIZE
697 #   define SQLITE_MAX_MMAP_SIZE 0
698 # endif
699 #endif
700 #ifndef SQLITE_MAX_MMAP_SIZE
701 # if defined(__linux__) \
702   || defined(_WIN32) \
703   || (defined(__APPLE__) && defined(__MACH__)) \
704   || defined(__sun)
705 #   define SQLITE_MAX_MMAP_SIZE 0x7fff0000  /* 2147418112 */
706 # else
707 #   define SQLITE_MAX_MMAP_SIZE 0
708 # endif
709 # define SQLITE_MAX_MMAP_SIZE_xc 1 /* exclude from ctime.c */
710 #endif
711 
712 /*
713 ** The default MMAP_SIZE is zero on all platforms.  Or, even if a larger
714 ** default MMAP_SIZE is specified at compile-time, make sure that it does
715 ** not exceed the maximum mmap size.
716 */
717 #ifndef SQLITE_DEFAULT_MMAP_SIZE
718 # define SQLITE_DEFAULT_MMAP_SIZE 0
719 # define SQLITE_DEFAULT_MMAP_SIZE_xc 1  /* Exclude from ctime.c */
720 #endif
721 #if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
722 # undef SQLITE_DEFAULT_MMAP_SIZE
723 # define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
724 #endif
725 
726 /*
727 ** Only one of SQLITE_ENABLE_STAT3 or SQLITE_ENABLE_STAT4 can be defined.
728 ** Priority is given to SQLITE_ENABLE_STAT4.  If either are defined, also
729 ** define SQLITE_ENABLE_STAT3_OR_STAT4
730 */
731 #ifdef SQLITE_ENABLE_STAT4
732 # undef SQLITE_ENABLE_STAT3
733 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
734 #elif SQLITE_ENABLE_STAT3
735 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
736 #elif SQLITE_ENABLE_STAT3_OR_STAT4
737 # undef SQLITE_ENABLE_STAT3_OR_STAT4
738 #endif
739 
740 /*
741 ** SELECTTRACE_ENABLED will be either 1 or 0 depending on whether or not
742 ** the Select query generator tracing logic is turned on.
743 */
744 #if defined(SQLITE_DEBUG) || defined(SQLITE_ENABLE_SELECTTRACE)
745 # define SELECTTRACE_ENABLED 1
746 #else
747 # define SELECTTRACE_ENABLED 0
748 #endif
749 
750 /*
751 ** An instance of the following structure is used to store the busy-handler
752 ** callback for a given sqlite handle.
753 **
754 ** The sqlite.busyHandler member of the sqlite struct contains the busy
755 ** callback for the database handle. Each pager opened via the sqlite
756 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
757 ** callback is currently invoked only from within pager.c.
758 */
759 typedef struct BusyHandler BusyHandler;
760 struct BusyHandler {
761   int (*xFunc)(void *,int);  /* The busy callback */
762   void *pArg;                /* First arg to busy callback */
763   int nBusy;                 /* Incremented with each busy call */
764 };
765 
766 /*
767 ** Name of the master database table.  The master database table
768 ** is a special table that holds the names and attributes of all
769 ** user tables and indices.
770 */
771 #define MASTER_NAME       "sqlite_master"
772 #define TEMP_MASTER_NAME  "sqlite_temp_master"
773 
774 /*
775 ** The root-page of the master database table.
776 */
777 #define MASTER_ROOT       1
778 
779 /*
780 ** The name of the schema table.
781 */
782 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
783 
784 /*
785 ** A convenience macro that returns the number of elements in
786 ** an array.
787 */
788 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
789 
790 /*
791 ** Determine if the argument is a power of two
792 */
793 #define IsPowerOfTwo(X) (((X)&((X)-1))==0)
794 
795 /*
796 ** The following value as a destructor means to use sqlite3DbFree().
797 ** The sqlite3DbFree() routine requires two parameters instead of the
798 ** one parameter that destructors normally want.  So we have to introduce
799 ** this magic value that the code knows to handle differently.  Any
800 ** pointer will work here as long as it is distinct from SQLITE_STATIC
801 ** and SQLITE_TRANSIENT.
802 */
803 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3MallocSize)
804 
805 /*
806 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
807 ** not support Writable Static Data (WSD) such as global and static variables.
808 ** All variables must either be on the stack or dynamically allocated from
809 ** the heap.  When WSD is unsupported, the variable declarations scattered
810 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
811 ** macro is used for this purpose.  And instead of referencing the variable
812 ** directly, we use its constant as a key to lookup the run-time allocated
813 ** buffer that holds real variable.  The constant is also the initializer
814 ** for the run-time allocated buffer.
815 **
816 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
817 ** macros become no-ops and have zero performance impact.
818 */
819 #ifdef SQLITE_OMIT_WSD
820   #define SQLITE_WSD const
821   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
822   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
823   int sqlite3_wsd_init(int N, int J);
824   void *sqlite3_wsd_find(void *K, int L);
825 #else
826   #define SQLITE_WSD
827   #define GLOBAL(t,v) v
828   #define sqlite3GlobalConfig sqlite3Config
829 #endif
830 
831 /*
832 ** The following macros are used to suppress compiler warnings and to
833 ** make it clear to human readers when a function parameter is deliberately
834 ** left unused within the body of a function. This usually happens when
835 ** a function is called via a function pointer. For example the
836 ** implementation of an SQL aggregate step callback may not use the
837 ** parameter indicating the number of arguments passed to the aggregate,
838 ** if it knows that this is enforced elsewhere.
839 **
840 ** When a function parameter is not used at all within the body of a function,
841 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
842 ** However, these macros may also be used to suppress warnings related to
843 ** parameters that may or may not be used depending on compilation options.
844 ** For example those parameters only used in assert() statements. In these
845 ** cases the parameters are named as per the usual conventions.
846 */
847 #define UNUSED_PARAMETER(x) (void)(x)
848 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
849 
850 /*
851 ** Forward references to structures
852 */
853 typedef struct AggInfo AggInfo;
854 typedef struct AuthContext AuthContext;
855 typedef struct AutoincInfo AutoincInfo;
856 typedef struct Bitvec Bitvec;
857 typedef struct CollSeq CollSeq;
858 typedef struct Column Column;
859 typedef struct Db Db;
860 typedef struct Schema Schema;
861 typedef struct Expr Expr;
862 typedef struct ExprList ExprList;
863 typedef struct ExprSpan ExprSpan;
864 typedef struct FKey FKey;
865 typedef struct FuncDestructor FuncDestructor;
866 typedef struct FuncDef FuncDef;
867 typedef struct FuncDefHash FuncDefHash;
868 typedef struct IdList IdList;
869 typedef struct Index Index;
870 typedef struct IndexSample IndexSample;
871 typedef struct KeyClass KeyClass;
872 typedef struct KeyInfo KeyInfo;
873 typedef struct Lookaside Lookaside;
874 typedef struct LookasideSlot LookasideSlot;
875 typedef struct Module Module;
876 typedef struct NameContext NameContext;
877 typedef struct Parse Parse;
878 typedef struct PrintfArguments PrintfArguments;
879 typedef struct RowSet RowSet;
880 typedef struct Savepoint Savepoint;
881 typedef struct Select Select;
882 typedef struct SQLiteThread SQLiteThread;
883 typedef struct SelectDest SelectDest;
884 typedef struct SrcList SrcList;
885 typedef struct StrAccum StrAccum;
886 typedef struct Table Table;
887 typedef struct TableLock TableLock;
888 typedef struct Token Token;
889 typedef struct TreeView TreeView;
890 typedef struct Trigger Trigger;
891 typedef struct TriggerPrg TriggerPrg;
892 typedef struct TriggerStep TriggerStep;
893 typedef struct UnpackedRecord UnpackedRecord;
894 typedef struct VTable VTable;
895 typedef struct VtabCtx VtabCtx;
896 typedef struct Walker Walker;
897 typedef struct WhereInfo WhereInfo;
898 typedef struct With With;
899 
900 /*
901 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
902 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
903 ** pointer types (i.e. FuncDef) defined above.
904 */
905 #include "btree.h"
906 #include "vdbe.h"
907 #include "pager.h"
908 #include "pcache.h"
909 
910 #include "os.h"
911 #include "mutex.h"
912 
913 
914 /*
915 ** Each database file to be accessed by the system is an instance
916 ** of the following structure.  There are normally two of these structures
917 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
918 ** aDb[1] is the database file used to hold temporary tables.  Additional
919 ** databases may be attached.
920 */
921 struct Db {
922   char *zName;         /* Name of this database */
923   Btree *pBt;          /* The B*Tree structure for this database file */
924   u8 safety_level;     /* How aggressive at syncing data to disk */
925   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
926 };
927 
928 /*
929 ** An instance of the following structure stores a database schema.
930 **
931 ** Most Schema objects are associated with a Btree.  The exception is
932 ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
933 ** In shared cache mode, a single Schema object can be shared by multiple
934 ** Btrees that refer to the same underlying BtShared object.
935 **
936 ** Schema objects are automatically deallocated when the last Btree that
937 ** references them is destroyed.   The TEMP Schema is manually freed by
938 ** sqlite3_close().
939 *
940 ** A thread must be holding a mutex on the corresponding Btree in order
941 ** to access Schema content.  This implies that the thread must also be
942 ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
943 ** For a TEMP Schema, only the connection mutex is required.
944 */
945 struct Schema {
946   int schema_cookie;   /* Database schema version number for this file */
947   int iGeneration;     /* Generation counter.  Incremented with each change */
948   Hash tblHash;        /* All tables indexed by name */
949   Hash idxHash;        /* All (named) indices indexed by name */
950   Hash trigHash;       /* All triggers indexed by name */
951   Hash fkeyHash;       /* All foreign keys by referenced table name */
952   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
953   u8 file_format;      /* Schema format version for this file */
954   u8 enc;              /* Text encoding used by this database */
955   u16 schemaFlags;     /* Flags associated with this schema */
956   int cache_size;      /* Number of pages to use in the cache */
957 };
958 
959 /*
960 ** These macros can be used to test, set, or clear bits in the
961 ** Db.pSchema->flags field.
962 */
963 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))
964 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->schemaFlags&(P))!=0)
965 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->schemaFlags|=(P)
966 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->schemaFlags&=~(P)
967 
968 /*
969 ** Allowed values for the DB.pSchema->flags field.
970 **
971 ** The DB_SchemaLoaded flag is set after the database schema has been
972 ** read into internal hash tables.
973 **
974 ** DB_UnresetViews means that one or more views have column names that
975 ** have been filled out.  If the schema changes, these column names might
976 ** changes and so the view will need to be reset.
977 */
978 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
979 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
980 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
981 
982 /*
983 ** The number of different kinds of things that can be limited
984 ** using the sqlite3_limit() interface.
985 */
986 #define SQLITE_N_LIMIT (SQLITE_LIMIT_WORKER_THREADS+1)
987 
988 /*
989 ** Lookaside malloc is a set of fixed-size buffers that can be used
990 ** to satisfy small transient memory allocation requests for objects
991 ** associated with a particular database connection.  The use of
992 ** lookaside malloc provides a significant performance enhancement
993 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
994 ** SQL statements.
995 **
996 ** The Lookaside structure holds configuration information about the
997 ** lookaside malloc subsystem.  Each available memory allocation in
998 ** the lookaside subsystem is stored on a linked list of LookasideSlot
999 ** objects.
1000 **
1001 ** Lookaside allocations are only allowed for objects that are associated
1002 ** with a particular database connection.  Hence, schema information cannot
1003 ** be stored in lookaside because in shared cache mode the schema information
1004 ** is shared by multiple database connections.  Therefore, while parsing
1005 ** schema information, the Lookaside.bEnabled flag is cleared so that
1006 ** lookaside allocations are not used to construct the schema objects.
1007 */
1008 struct Lookaside {
1009   u16 sz;                 /* Size of each buffer in bytes */
1010   u8 bEnabled;            /* False to disable new lookaside allocations */
1011   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
1012   int nOut;               /* Number of buffers currently checked out */
1013   int mxOut;              /* Highwater mark for nOut */
1014   int anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
1015   LookasideSlot *pFree;   /* List of available buffers */
1016   void *pStart;           /* First byte of available memory space */
1017   void *pEnd;             /* First byte past end of available space */
1018 };
1019 struct LookasideSlot {
1020   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
1021 };
1022 
1023 /*
1024 ** A hash table for function definitions.
1025 **
1026 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
1027 ** Collisions are on the FuncDef.pHash chain.
1028 */
1029 struct FuncDefHash {
1030   FuncDef *a[23];       /* Hash table for functions */
1031 };
1032 
1033 #ifdef SQLITE_USER_AUTHENTICATION
1034 /*
1035 ** Information held in the "sqlite3" database connection object and used
1036 ** to manage user authentication.
1037 */
1038 typedef struct sqlite3_userauth sqlite3_userauth;
1039 struct sqlite3_userauth {
1040   u8 authLevel;                 /* Current authentication level */
1041   int nAuthPW;                  /* Size of the zAuthPW in bytes */
1042   char *zAuthPW;                /* Password used to authenticate */
1043   char *zAuthUser;              /* User name used to authenticate */
1044 };
1045 
1046 /* Allowed values for sqlite3_userauth.authLevel */
1047 #define UAUTH_Unknown     0     /* Authentication not yet checked */
1048 #define UAUTH_Fail        1     /* User authentication failed */
1049 #define UAUTH_User        2     /* Authenticated as a normal user */
1050 #define UAUTH_Admin       3     /* Authenticated as an administrator */
1051 
1052 /* Functions used only by user authorization logic */
1053 int sqlite3UserAuthTable(const char*);
1054 int sqlite3UserAuthCheckLogin(sqlite3*,const char*,u8*);
1055 void sqlite3UserAuthInit(sqlite3*);
1056 void sqlite3CryptFunc(sqlite3_context*,int,sqlite3_value**);
1057 
1058 #endif /* SQLITE_USER_AUTHENTICATION */
1059 
1060 /*
1061 ** typedef for the authorization callback function.
1062 */
1063 #ifdef SQLITE_USER_AUTHENTICATION
1064   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1065                                const char*, const char*);
1066 #else
1067   typedef int (*sqlite3_xauth)(void*,int,const char*,const char*,const char*,
1068                                const char*);
1069 #endif
1070 
1071 
1072 /*
1073 ** Each database connection is an instance of the following structure.
1074 */
1075 struct sqlite3 {
1076   sqlite3_vfs *pVfs;            /* OS Interface */
1077   struct Vdbe *pVdbe;           /* List of active virtual machines */
1078   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
1079   sqlite3_mutex *mutex;         /* Connection mutex */
1080   Db *aDb;                      /* All backends */
1081   int nDb;                      /* Number of backends currently in use */
1082   int flags;                    /* Miscellaneous flags. See below */
1083   i64 lastRowid;                /* ROWID of most recent insert (see above) */
1084   i64 szMmap;                   /* Default mmap_size setting */
1085   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
1086   int errCode;                  /* Most recent error code (SQLITE_*) */
1087   int errMask;                  /* & result codes with this before returning */
1088   u16 dbOptFlags;               /* Flags to enable/disable optimizations */
1089   u8 enc;                       /* Text encoding */
1090   u8 autoCommit;                /* The auto-commit flag. */
1091   u8 temp_store;                /* 1: file 2: memory 0: default */
1092   u8 mallocFailed;              /* True if we have seen a malloc failure */
1093   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
1094   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
1095   u8 suppressErr;               /* Do not issue error messages if true */
1096   u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
1097   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
1098   int nextPagesize;             /* Pagesize after VACUUM if >0 */
1099   u32 magic;                    /* Magic number for detect library misuse */
1100   int nChange;                  /* Value returned by sqlite3_changes() */
1101   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
1102   int aLimit[SQLITE_N_LIMIT];   /* Limits */
1103   int nMaxSorterMmap;           /* Maximum size of regions mapped by sorter */
1104   struct sqlite3InitInfo {      /* Information used during initialization */
1105     int newTnum;                /* Rootpage of table being initialized */
1106     u8 iDb;                     /* Which db file is being initialized */
1107     u8 busy;                    /* TRUE if currently initializing */
1108     u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
1109     u8 imposterTable;           /* Building an imposter table */
1110   } init;
1111   int nVdbeActive;              /* Number of VDBEs currently running */
1112   int nVdbeRead;                /* Number of active VDBEs that read or write */
1113   int nVdbeWrite;               /* Number of active VDBEs that read and write */
1114   int nVdbeExec;                /* Number of nested calls to VdbeExec() */
1115   int nVDestroy;                /* Number of active OP_VDestroy operations */
1116   int nExtension;               /* Number of loaded extensions */
1117   void **aExtension;            /* Array of shared library handles */
1118   void (*xTrace)(void*,const char*);        /* Trace function */
1119   void *pTraceArg;                          /* Argument to the trace function */
1120   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
1121   void *pProfileArg;                        /* Argument to profile function */
1122   void *pCommitArg;                 /* Argument to xCommitCallback() */
1123   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
1124   void *pRollbackArg;               /* Argument to xRollbackCallback() */
1125   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
1126   void *pUpdateArg;
1127   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
1128 #ifndef SQLITE_OMIT_WAL
1129   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
1130   void *pWalArg;
1131 #endif
1132   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
1133   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
1134   void *pCollNeededArg;
1135   sqlite3_value *pErr;          /* Most recent error message */
1136   union {
1137     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
1138     double notUsed1;            /* Spacer */
1139   } u1;
1140   Lookaside lookaside;          /* Lookaside malloc configuration */
1141 #ifndef SQLITE_OMIT_AUTHORIZATION
1142   sqlite3_xauth xAuth;          /* Access authorization function */
1143   void *pAuthArg;               /* 1st argument to the access auth function */
1144 #endif
1145 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
1146   int (*xProgress)(void *);     /* The progress callback */
1147   void *pProgressArg;           /* Argument to the progress callback */
1148   unsigned nProgressOps;        /* Number of opcodes for progress callback */
1149 #endif
1150 #ifndef SQLITE_OMIT_VIRTUALTABLE
1151   int nVTrans;                  /* Allocated size of aVTrans */
1152   Hash aModule;                 /* populated by sqlite3_create_module() */
1153   VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
1154   VTable **aVTrans;             /* Virtual tables with open transactions */
1155   VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
1156 #endif
1157   FuncDefHash aFunc;            /* Hash table of connection functions */
1158   Hash aCollSeq;                /* All collating sequences */
1159   BusyHandler busyHandler;      /* Busy callback */
1160   Db aDbStatic[2];              /* Static space for the 2 default backends */
1161   Savepoint *pSavepoint;        /* List of active savepoints */
1162   int busyTimeout;              /* Busy handler timeout, in msec */
1163   int nSavepoint;               /* Number of non-transaction savepoints */
1164   int nStatement;               /* Number of nested statement-transactions  */
1165   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
1166   i64 nDeferredImmCons;         /* Net deferred immediate constraints */
1167   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
1168 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
1169   /* The following variables are all protected by the STATIC_MASTER
1170   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
1171   **
1172   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
1173   ** unlock so that it can proceed.
1174   **
1175   ** When X.pBlockingConnection==Y, that means that something that X tried
1176   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
1177   ** held by Y.
1178   */
1179   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
1180   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
1181   void *pUnlockArg;                     /* Argument to xUnlockNotify */
1182   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
1183   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
1184 #endif
1185 #ifdef SQLITE_USER_AUTHENTICATION
1186   sqlite3_userauth auth;        /* User authentication information */
1187 #endif
1188 };
1189 
1190 /*
1191 ** A macro to discover the encoding of a database.
1192 */
1193 #define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
1194 #define ENC(db)        ((db)->enc)
1195 
1196 /*
1197 ** Possible values for the sqlite3.flags.
1198 */
1199 #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
1200 #define SQLITE_InternChanges  0x00000002  /* Uncommitted Hash table changes */
1201 #define SQLITE_FullFSync      0x00000004  /* Use full fsync on the backend */
1202 #define SQLITE_CkptFullFSync  0x00000008  /* Use full fsync for checkpoint */
1203 #define SQLITE_CacheSpill     0x00000010  /* OK to spill pager cache */
1204 #define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
1205 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
1206 #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
1207                                           /*   DELETE, or UPDATE and return */
1208                                           /*   the count using a callback. */
1209 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
1210                                           /*   result set is empty */
1211 #define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
1212 #define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
1213 #define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
1214 #define SQLITE_VdbeAddopTrace 0x00001000  /* Trace sqlite3VdbeAddOp() calls */
1215 #define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
1216 #define SQLITE_ReadUncommitted 0x0004000  /* For shared-cache mode */
1217 #define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
1218 #define SQLITE_RecoveryMode   0x00010000  /* Ignore schema errors */
1219 #define SQLITE_ReverseOrder   0x00020000  /* Reverse unordered SELECTs */
1220 #define SQLITE_RecTriggers    0x00040000  /* Enable recursive triggers */
1221 #define SQLITE_ForeignKeys    0x00080000  /* Enforce foreign key constraints  */
1222 #define SQLITE_AutoIndex      0x00100000  /* Enable automatic indexes */
1223 #define SQLITE_PreferBuiltin  0x00200000  /* Preference to built-in funcs */
1224 #define SQLITE_LoadExtension  0x00400000  /* Enable load_extension */
1225 #define SQLITE_EnableTrigger  0x00800000  /* True to enable triggers */
1226 #define SQLITE_DeferFKs       0x01000000  /* Defer all FK constraints */
1227 #define SQLITE_QueryOnly      0x02000000  /* Disable database changes */
1228 #define SQLITE_VdbeEQP        0x04000000  /* Debug EXPLAIN QUERY PLAN */
1229 
1230 
1231 /*
1232 ** Bits of the sqlite3.dbOptFlags field that are used by the
1233 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
1234 ** selectively disable various optimizations.
1235 */
1236 #define SQLITE_QueryFlattener 0x0001   /* Query flattening */
1237 #define SQLITE_ColumnCache    0x0002   /* Column cache */
1238 #define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
1239 #define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
1240 /*                not used    0x0010   // Was: SQLITE_IdxRealAsInt */
1241 #define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
1242 #define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
1243 #define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
1244 #define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
1245 #define SQLITE_Transitive     0x0200   /* Transitive constraints */
1246 #define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
1247 #define SQLITE_Stat34         0x0800   /* Use STAT3 or STAT4 data */
1248 #define SQLITE_AllOpts        0xffff   /* All optimizations */
1249 
1250 /*
1251 ** Macros for testing whether or not optimizations are enabled or disabled.
1252 */
1253 #ifndef SQLITE_OMIT_BUILTIN_TEST
1254 #define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
1255 #define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
1256 #else
1257 #define OptimizationDisabled(db, mask)  0
1258 #define OptimizationEnabled(db, mask)   1
1259 #endif
1260 
1261 /*
1262 ** Return true if it OK to factor constant expressions into the initialization
1263 ** code. The argument is a Parse object for the code generator.
1264 */
1265 #define ConstFactorOk(P) ((P)->okConstFactor)
1266 
1267 /*
1268 ** Possible values for the sqlite.magic field.
1269 ** The numbers are obtained at random and have no special meaning, other
1270 ** than being distinct from one another.
1271 */
1272 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
1273 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
1274 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
1275 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
1276 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
1277 #define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */
1278 
1279 /*
1280 ** Each SQL function is defined by an instance of the following
1281 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
1282 ** hash table.  When multiple functions have the same name, the hash table
1283 ** points to a linked list of these structures.
1284 */
1285 struct FuncDef {
1286   i16 nArg;            /* Number of arguments.  -1 means unlimited */
1287   u16 funcFlags;       /* Some combination of SQLITE_FUNC_* */
1288   void *pUserData;     /* User data parameter */
1289   FuncDef *pNext;      /* Next function with same name */
1290   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
1291   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
1292   void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
1293   char *zName;         /* SQL name of the function. */
1294   FuncDef *pHash;      /* Next with a different name but the same hash */
1295   FuncDestructor *pDestructor;   /* Reference counted destructor function */
1296 };
1297 
1298 /*
1299 ** This structure encapsulates a user-function destructor callback (as
1300 ** configured using create_function_v2()) and a reference counter. When
1301 ** create_function_v2() is called to create a function with a destructor,
1302 ** a single object of this type is allocated. FuncDestructor.nRef is set to
1303 ** the number of FuncDef objects created (either 1 or 3, depending on whether
1304 ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
1305 ** member of each of the new FuncDef objects is set to point to the allocated
1306 ** FuncDestructor.
1307 **
1308 ** Thereafter, when one of the FuncDef objects is deleted, the reference
1309 ** count on this object is decremented. When it reaches 0, the destructor
1310 ** is invoked and the FuncDestructor structure freed.
1311 */
1312 struct FuncDestructor {
1313   int nRef;
1314   void (*xDestroy)(void *);
1315   void *pUserData;
1316 };
1317 
1318 /*
1319 ** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
1320 ** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  There
1321 ** are assert() statements in the code to verify this.
1322 */
1323 #define SQLITE_FUNC_ENCMASK  0x003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
1324 #define SQLITE_FUNC_LIKE     0x004 /* Candidate for the LIKE optimization */
1325 #define SQLITE_FUNC_CASE     0x008 /* Case-sensitive LIKE-type function */
1326 #define SQLITE_FUNC_EPHEM    0x010 /* Ephemeral.  Delete with VDBE */
1327 #define SQLITE_FUNC_NEEDCOLL 0x020 /* sqlite3GetFuncCollSeq() might be called */
1328 #define SQLITE_FUNC_LENGTH   0x040 /* Built-in length() function */
1329 #define SQLITE_FUNC_TYPEOF   0x080 /* Built-in typeof() function */
1330 #define SQLITE_FUNC_COUNT    0x100 /* Built-in count(*) aggregate */
1331 #define SQLITE_FUNC_COALESCE 0x200 /* Built-in coalesce() or ifnull() */
1332 #define SQLITE_FUNC_UNLIKELY 0x400 /* Built-in unlikely() function */
1333 #define SQLITE_FUNC_CONSTANT 0x800 /* Constant inputs give a constant output */
1334 #define SQLITE_FUNC_MINMAX  0x1000 /* True for min() and max() aggregates */
1335 
1336 /*
1337 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
1338 ** used to create the initializers for the FuncDef structures.
1339 **
1340 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
1341 **     Used to create a scalar function definition of a function zName
1342 **     implemented by C function xFunc that accepts nArg arguments. The
1343 **     value passed as iArg is cast to a (void*) and made available
1344 **     as the user-data (sqlite3_user_data()) for the function. If
1345 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
1346 **
1347 **   VFUNCTION(zName, nArg, iArg, bNC, xFunc)
1348 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
1349 **
1350 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
1351 **     Used to create an aggregate function definition implemented by
1352 **     the C functions xStep and xFinal. The first four parameters
1353 **     are interpreted in the same way as the first 4 parameters to
1354 **     FUNCTION().
1355 **
1356 **   LIKEFUNC(zName, nArg, pArg, flags)
1357 **     Used to create a scalar function definition of a function zName
1358 **     that accepts nArg arguments and is implemented by a call to C
1359 **     function likeFunc. Argument pArg is cast to a (void *) and made
1360 **     available as the function user-data (sqlite3_user_data()). The
1361 **     FuncDef.flags variable is set to the value passed as the flags
1362 **     parameter.
1363 */
1364 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1365   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1366    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1367 #define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1368   {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1369    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1370 #define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
1371   {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
1372    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1373 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
1374   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1375    pArg, 0, xFunc, 0, 0, #zName, 0, 0}
1376 #define LIKEFUNC(zName, nArg, arg, flags) \
1377   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
1378    (void *)arg, 0, likeFunc, 0, 0, #zName, 0, 0}
1379 #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
1380   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
1381    SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}
1382 #define AGGREGATE2(zName, nArg, arg, nc, xStep, xFinal, extraFlags) \
1383   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|extraFlags, \
1384    SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}
1385 
1386 /*
1387 ** All current savepoints are stored in a linked list starting at
1388 ** sqlite3.pSavepoint. The first element in the list is the most recently
1389 ** opened savepoint. Savepoints are added to the list by the vdbe
1390 ** OP_Savepoint instruction.
1391 */
1392 struct Savepoint {
1393   char *zName;                        /* Savepoint name (nul-terminated) */
1394   i64 nDeferredCons;                  /* Number of deferred fk violations */
1395   i64 nDeferredImmCons;               /* Number of deferred imm fk. */
1396   Savepoint *pNext;                   /* Parent savepoint (if any) */
1397 };
1398 
1399 /*
1400 ** The following are used as the second parameter to sqlite3Savepoint(),
1401 ** and as the P1 argument to the OP_Savepoint instruction.
1402 */
1403 #define SAVEPOINT_BEGIN      0
1404 #define SAVEPOINT_RELEASE    1
1405 #define SAVEPOINT_ROLLBACK   2
1406 
1407 
1408 /*
1409 ** Each SQLite module (virtual table definition) is defined by an
1410 ** instance of the following structure, stored in the sqlite3.aModule
1411 ** hash table.
1412 */
1413 struct Module {
1414   const sqlite3_module *pModule;       /* Callback pointers */
1415   const char *zName;                   /* Name passed to create_module() */
1416   void *pAux;                          /* pAux passed to create_module() */
1417   void (*xDestroy)(void *);            /* Module destructor function */
1418 };
1419 
1420 /*
1421 ** information about each column of an SQL table is held in an instance
1422 ** of this structure.
1423 */
1424 struct Column {
1425   char *zName;     /* Name of this column */
1426   Expr *pDflt;     /* Default value of this column */
1427   char *zDflt;     /* Original text of the default value */
1428   char *zType;     /* Data type for this column */
1429   char *zColl;     /* Collating sequence.  If NULL, use the default */
1430   u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
1431   char affinity;   /* One of the SQLITE_AFF_... values */
1432   u8 szEst;        /* Estimated size of this column.  INT==1 */
1433   u8 colFlags;     /* Boolean properties.  See COLFLAG_ defines below */
1434 };
1435 
1436 /* Allowed values for Column.colFlags:
1437 */
1438 #define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
1439 #define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */
1440 
1441 /*
1442 ** A "Collating Sequence" is defined by an instance of the following
1443 ** structure. Conceptually, a collating sequence consists of a name and
1444 ** a comparison routine that defines the order of that sequence.
1445 **
1446 ** If CollSeq.xCmp is NULL, it means that the
1447 ** collating sequence is undefined.  Indices built on an undefined
1448 ** collating sequence may not be read or written.
1449 */
1450 struct CollSeq {
1451   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
1452   u8 enc;               /* Text encoding handled by xCmp() */
1453   void *pUser;          /* First argument to xCmp() */
1454   int (*xCmp)(void*,int, const void*, int, const void*);
1455   void (*xDel)(void*);  /* Destructor for pUser */
1456 };
1457 
1458 /*
1459 ** A sort order can be either ASC or DESC.
1460 */
1461 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
1462 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
1463 
1464 /*
1465 ** Column affinity types.
1466 **
1467 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
1468 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
1469 ** the speed a little by numbering the values consecutively.
1470 **
1471 ** But rather than start with 0 or 1, we begin with 'A'.  That way,
1472 ** when multiple affinity types are concatenated into a string and
1473 ** used as the P4 operand, they will be more readable.
1474 **
1475 ** Note also that the numeric types are grouped together so that testing
1476 ** for a numeric type is a single comparison.  And the NONE type is first.
1477 */
1478 #define SQLITE_AFF_NONE     'A'
1479 #define SQLITE_AFF_TEXT     'B'
1480 #define SQLITE_AFF_NUMERIC  'C'
1481 #define SQLITE_AFF_INTEGER  'D'
1482 #define SQLITE_AFF_REAL     'E'
1483 
1484 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
1485 
1486 /*
1487 ** The SQLITE_AFF_MASK values masks off the significant bits of an
1488 ** affinity value.
1489 */
1490 #define SQLITE_AFF_MASK     0x47
1491 
1492 /*
1493 ** Additional bit values that can be ORed with an affinity without
1494 ** changing the affinity.
1495 **
1496 ** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
1497 ** It causes an assert() to fire if either operand to a comparison
1498 ** operator is NULL.  It is added to certain comparison operators to
1499 ** prove that the operands are always NOT NULL.
1500 */
1501 #define SQLITE_JUMPIFNULL   0x10  /* jumps if either operand is NULL */
1502 #define SQLITE_STOREP2      0x20  /* Store result in reg[P2] rather than jump */
1503 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
1504 #define SQLITE_NOTNULL      0x90  /* Assert that operands are never NULL */
1505 
1506 /*
1507 ** An object of this type is created for each virtual table present in
1508 ** the database schema.
1509 **
1510 ** If the database schema is shared, then there is one instance of this
1511 ** structure for each database connection (sqlite3*) that uses the shared
1512 ** schema. This is because each database connection requires its own unique
1513 ** instance of the sqlite3_vtab* handle used to access the virtual table
1514 ** implementation. sqlite3_vtab* handles can not be shared between
1515 ** database connections, even when the rest of the in-memory database
1516 ** schema is shared, as the implementation often stores the database
1517 ** connection handle passed to it via the xConnect() or xCreate() method
1518 ** during initialization internally. This database connection handle may
1519 ** then be used by the virtual table implementation to access real tables
1520 ** within the database. So that they appear as part of the callers
1521 ** transaction, these accesses need to be made via the same database
1522 ** connection as that used to execute SQL operations on the virtual table.
1523 **
1524 ** All VTable objects that correspond to a single table in a shared
1525 ** database schema are initially stored in a linked-list pointed to by
1526 ** the Table.pVTable member variable of the corresponding Table object.
1527 ** When an sqlite3_prepare() operation is required to access the virtual
1528 ** table, it searches the list for the VTable that corresponds to the
1529 ** database connection doing the preparing so as to use the correct
1530 ** sqlite3_vtab* handle in the compiled query.
1531 **
1532 ** When an in-memory Table object is deleted (for example when the
1533 ** schema is being reloaded for some reason), the VTable objects are not
1534 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
1535 ** immediately. Instead, they are moved from the Table.pVTable list to
1536 ** another linked list headed by the sqlite3.pDisconnect member of the
1537 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
1538 ** next time a statement is prepared using said sqlite3*. This is done
1539 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
1540 ** Refer to comments above function sqlite3VtabUnlockList() for an
1541 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
1542 ** list without holding the corresponding sqlite3.mutex mutex.
1543 **
1544 ** The memory for objects of this type is always allocated by
1545 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
1546 ** the first argument.
1547 */
1548 struct VTable {
1549   sqlite3 *db;              /* Database connection associated with this table */
1550   Module *pMod;             /* Pointer to module implementation */
1551   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
1552   int nRef;                 /* Number of pointers to this structure */
1553   u8 bConstraint;           /* True if constraints are supported */
1554   int iSavepoint;           /* Depth of the SAVEPOINT stack */
1555   VTable *pNext;            /* Next in linked list (see above) */
1556 };
1557 
1558 /*
1559 ** Each SQL table is represented in memory by an instance of the
1560 ** following structure.
1561 **
1562 ** Table.zName is the name of the table.  The case of the original
1563 ** CREATE TABLE statement is stored, but case is not significant for
1564 ** comparisons.
1565 **
1566 ** Table.nCol is the number of columns in this table.  Table.aCol is a
1567 ** pointer to an array of Column structures, one for each column.
1568 **
1569 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
1570 ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
1571 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
1572 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
1573 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
1574 ** is generated for each row of the table.  TF_HasPrimaryKey is set if
1575 ** the table has any PRIMARY KEY, INTEGER or otherwise.
1576 **
1577 ** Table.tnum is the page number for the root BTree page of the table in the
1578 ** database file.  If Table.iDb is the index of the database table backend
1579 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
1580 ** holds temporary tables and indices.  If TF_Ephemeral is set
1581 ** then the table is stored in a file that is automatically deleted
1582 ** when the VDBE cursor to the table is closed.  In this case Table.tnum
1583 ** refers VDBE cursor number that holds the table open, not to the root
1584 ** page number.  Transient tables are used to hold the results of a
1585 ** sub-query that appears instead of a real table name in the FROM clause
1586 ** of a SELECT statement.
1587 */
1588 struct Table {
1589   char *zName;         /* Name of the table or view */
1590   Column *aCol;        /* Information about each column */
1591   Index *pIndex;       /* List of SQL indexes on this table. */
1592   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
1593   FKey *pFKey;         /* Linked list of all foreign keys in this table */
1594   char *zColAff;       /* String defining the affinity of each column */
1595 #ifndef SQLITE_OMIT_CHECK
1596   ExprList *pCheck;    /* All CHECK constraints */
1597 #endif
1598   LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
1599   int tnum;            /* Root BTree node for this table (see note above) */
1600   i16 iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
1601   i16 nCol;            /* Number of columns in this table */
1602   u16 nRef;            /* Number of pointers to this Table */
1603   LogEst szTabRow;     /* Estimated size of each table row in bytes */
1604 #ifdef SQLITE_ENABLE_COSTMULT
1605   LogEst costMult;     /* Cost multiplier for using this table */
1606 #endif
1607   u8 tabFlags;         /* Mask of TF_* values */
1608   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
1609 #ifndef SQLITE_OMIT_ALTERTABLE
1610   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
1611 #endif
1612 #ifndef SQLITE_OMIT_VIRTUALTABLE
1613   int nModuleArg;      /* Number of arguments to the module */
1614   char **azModuleArg;  /* Text of all module args. [0] is module name */
1615   VTable *pVTable;     /* List of VTable objects. */
1616 #endif
1617   Trigger *pTrigger;   /* List of triggers stored in pSchema */
1618   Schema *pSchema;     /* Schema that contains this table */
1619   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
1620 };
1621 
1622 /*
1623 ** Allowed values for Table.tabFlags.
1624 */
1625 #define TF_Readonly        0x01    /* Read-only system table */
1626 #define TF_Ephemeral       0x02    /* An ephemeral table */
1627 #define TF_HasPrimaryKey   0x04    /* Table has a primary key */
1628 #define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
1629 #define TF_Virtual         0x10    /* Is a virtual table */
1630 #define TF_WithoutRowid    0x20    /* No rowid used. PRIMARY KEY is the key */
1631 
1632 
1633 /*
1634 ** Test to see whether or not a table is a virtual table.  This is
1635 ** done as a macro so that it will be optimized out when virtual
1636 ** table support is omitted from the build.
1637 */
1638 #ifndef SQLITE_OMIT_VIRTUALTABLE
1639 #  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
1640 #  define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1641 #else
1642 #  define IsVirtual(X)      0
1643 #  define IsHiddenColumn(X) 0
1644 #endif
1645 
1646 /* Does the table have a rowid */
1647 #define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
1648 
1649 /*
1650 ** Each foreign key constraint is an instance of the following structure.
1651 **
1652 ** A foreign key is associated with two tables.  The "from" table is
1653 ** the table that contains the REFERENCES clause that creates the foreign
1654 ** key.  The "to" table is the table that is named in the REFERENCES clause.
1655 ** Consider this example:
1656 **
1657 **     CREATE TABLE ex1(
1658 **       a INTEGER PRIMARY KEY,
1659 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
1660 **     );
1661 **
1662 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
1663 ** Equivalent names:
1664 **
1665 **     from-table == child-table
1666 **       to-table == parent-table
1667 **
1668 ** Each REFERENCES clause generates an instance of the following structure
1669 ** which is attached to the from-table.  The to-table need not exist when
1670 ** the from-table is created.  The existence of the to-table is not checked.
1671 **
1672 ** The list of all parents for child Table X is held at X.pFKey.
1673 **
1674 ** A list of all children for a table named Z (which might not even exist)
1675 ** is held in Schema.fkeyHash with a hash key of Z.
1676 */
1677 struct FKey {
1678   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
1679   FKey *pNextFrom;  /* Next FKey with the same in pFrom. Next parent of pFrom */
1680   char *zTo;        /* Name of table that the key points to (aka: Parent) */
1681   FKey *pNextTo;    /* Next with the same zTo. Next child of zTo. */
1682   FKey *pPrevTo;    /* Previous with the same zTo */
1683   int nCol;         /* Number of columns in this key */
1684   /* EV: R-30323-21917 */
1685   u8 isDeferred;       /* True if constraint checking is deferred till COMMIT */
1686   u8 aAction[2];        /* ON DELETE and ON UPDATE actions, respectively */
1687   Trigger *apTrigger[2];/* Triggers for aAction[] actions */
1688   struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
1689     int iFrom;            /* Index of column in pFrom */
1690     char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
1691   } aCol[1];            /* One entry for each of nCol columns */
1692 };
1693 
1694 /*
1695 ** SQLite supports many different ways to resolve a constraint
1696 ** error.  ROLLBACK processing means that a constraint violation
1697 ** causes the operation in process to fail and for the current transaction
1698 ** to be rolled back.  ABORT processing means the operation in process
1699 ** fails and any prior changes from that one operation are backed out,
1700 ** but the transaction is not rolled back.  FAIL processing means that
1701 ** the operation in progress stops and returns an error code.  But prior
1702 ** changes due to the same operation are not backed out and no rollback
1703 ** occurs.  IGNORE means that the particular row that caused the constraint
1704 ** error is not inserted or updated.  Processing continues and no error
1705 ** is returned.  REPLACE means that preexisting database rows that caused
1706 ** a UNIQUE constraint violation are removed so that the new insert or
1707 ** update can proceed.  Processing continues and no error is reported.
1708 **
1709 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
1710 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
1711 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
1712 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
1713 ** referenced table row is propagated into the row that holds the
1714 ** foreign key.
1715 **
1716 ** The following symbolic values are used to record which type
1717 ** of action to take.
1718 */
1719 #define OE_None     0   /* There is no constraint to check */
1720 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
1721 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
1722 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
1723 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
1724 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
1725 
1726 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
1727 #define OE_SetNull  7   /* Set the foreign key value to NULL */
1728 #define OE_SetDflt  8   /* Set the foreign key value to its default */
1729 #define OE_Cascade  9   /* Cascade the changes */
1730 
1731 #define OE_Default  10  /* Do whatever the default action is */
1732 
1733 
1734 /*
1735 ** An instance of the following structure is passed as the first
1736 ** argument to sqlite3VdbeKeyCompare and is used to control the
1737 ** comparison of the two index keys.
1738 **
1739 ** Note that aSortOrder[] and aColl[] have nField+1 slots.  There
1740 ** are nField slots for the columns of an index then one extra slot
1741 ** for the rowid at the end.
1742 */
1743 struct KeyInfo {
1744   u32 nRef;           /* Number of references to this KeyInfo object */
1745   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
1746   u16 nField;         /* Number of key columns in the index */
1747   u16 nXField;        /* Number of columns beyond the key columns */
1748   sqlite3 *db;        /* The database connection */
1749   u8 *aSortOrder;     /* Sort order for each column. */
1750   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
1751 };
1752 
1753 /*
1754 ** An instance of the following structure holds information about a
1755 ** single index record that has already been parsed out into individual
1756 ** values.
1757 **
1758 ** A record is an object that contains one or more fields of data.
1759 ** Records are used to store the content of a table row and to store
1760 ** the key of an index.  A blob encoding of a record is created by
1761 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
1762 ** OP_Column opcode.
1763 **
1764 ** This structure holds a record that has already been disassembled
1765 ** into its constituent fields.
1766 **
1767 ** The r1 and r2 member variables are only used by the optimized comparison
1768 ** functions vdbeRecordCompareInt() and vdbeRecordCompareString().
1769 */
1770 struct UnpackedRecord {
1771   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
1772   u16 nField;         /* Number of entries in apMem[] */
1773   i8 default_rc;      /* Comparison result if keys are equal */
1774   u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
1775   Mem *aMem;          /* Values */
1776   int r1;             /* Value to return if (lhs > rhs) */
1777   int r2;             /* Value to return if (rhs < lhs) */
1778 };
1779 
1780 
1781 /*
1782 ** Each SQL index is represented in memory by an
1783 ** instance of the following structure.
1784 **
1785 ** The columns of the table that are to be indexed are described
1786 ** by the aiColumn[] field of this structure.  For example, suppose
1787 ** we have the following table and index:
1788 **
1789 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
1790 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
1791 **
1792 ** In the Table structure describing Ex1, nCol==3 because there are
1793 ** three columns in the table.  In the Index structure describing
1794 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
1795 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
1796 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
1797 ** The second column to be indexed (c1) has an index of 0 in
1798 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
1799 **
1800 ** The Index.onError field determines whether or not the indexed columns
1801 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
1802 ** it means this is not a unique index.  Otherwise it is a unique index
1803 ** and the value of Index.onError indicate the which conflict resolution
1804 ** algorithm to employ whenever an attempt is made to insert a non-unique
1805 ** element.
1806 */
1807 struct Index {
1808   char *zName;             /* Name of this index */
1809   i16 *aiColumn;           /* Which columns are used by this index.  1st is 0 */
1810   LogEst *aiRowLogEst;     /* From ANALYZE: Est. rows selected by each column */
1811   Table *pTable;           /* The SQL table being indexed */
1812   char *zColAff;           /* String defining the affinity of each column */
1813   Index *pNext;            /* The next index associated with the same table */
1814   Schema *pSchema;         /* Schema containing this index */
1815   u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
1816   char **azColl;           /* Array of collation sequence names for index */
1817   Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
1818   int tnum;                /* DB Page containing root of this index */
1819   LogEst szIdxRow;         /* Estimated average row size in bytes */
1820   u16 nKeyCol;             /* Number of columns forming the key */
1821   u16 nColumn;             /* Number of columns stored in the index */
1822   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
1823   unsigned idxType:2;      /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
1824   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
1825   unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
1826   unsigned isResized:1;    /* True if resizeIndexObject() has been called */
1827   unsigned isCovering:1;   /* True if this is a covering index */
1828   unsigned noSkipScan:1;   /* Do not try to use skip-scan if true */
1829 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
1830   int nSample;             /* Number of elements in aSample[] */
1831   int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
1832   tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
1833   IndexSample *aSample;    /* Samples of the left-most key */
1834   tRowcnt *aiRowEst;       /* Non-logarithmic stat1 data for this index */
1835   tRowcnt nRowEst0;        /* Non-logarithmic number of rows in the index */
1836 #endif
1837 };
1838 
1839 /*
1840 ** Allowed values for Index.idxType
1841 */
1842 #define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
1843 #define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */
1844 #define SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */
1845 
1846 /* Return true if index X is a PRIMARY KEY index */
1847 #define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
1848 
1849 /* Return true if index X is a UNIQUE index */
1850 #define IsUniqueIndex(X)      ((X)->onError!=OE_None)
1851 
1852 /*
1853 ** Each sample stored in the sqlite_stat3 table is represented in memory
1854 ** using a structure of this type.  See documentation at the top of the
1855 ** analyze.c source file for additional information.
1856 */
1857 struct IndexSample {
1858   void *p;          /* Pointer to sampled record */
1859   int n;            /* Size of record in bytes */
1860   tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
1861   tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
1862   tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
1863 };
1864 
1865 /*
1866 ** Each token coming out of the lexer is an instance of
1867 ** this structure.  Tokens are also used as part of an expression.
1868 **
1869 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
1870 ** may contain random values.  Do not make any assumptions about Token.dyn
1871 ** and Token.n when Token.z==0.
1872 */
1873 struct Token {
1874   const char *z;     /* Text of the token.  Not NULL-terminated! */
1875   unsigned int n;    /* Number of characters in this token */
1876 };
1877 
1878 /*
1879 ** An instance of this structure contains information needed to generate
1880 ** code for a SELECT that contains aggregate functions.
1881 **
1882 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
1883 ** pointer to this structure.  The Expr.iColumn field is the index in
1884 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
1885 ** code for that node.
1886 **
1887 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
1888 ** original Select structure that describes the SELECT statement.  These
1889 ** fields do not need to be freed when deallocating the AggInfo structure.
1890 */
1891 struct AggInfo {
1892   u8 directMode;          /* Direct rendering mode means take data directly
1893                           ** from source tables rather than from accumulators */
1894   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
1895                           ** than the source table */
1896   int sortingIdx;         /* Cursor number of the sorting index */
1897   int sortingIdxPTab;     /* Cursor number of pseudo-table */
1898   int nSortingColumn;     /* Number of columns in the sorting index */
1899   int mnReg, mxReg;       /* Range of registers allocated for aCol and aFunc */
1900   ExprList *pGroupBy;     /* The group by clause */
1901   struct AggInfo_col {    /* For each column used in source tables */
1902     Table *pTab;             /* Source table */
1903     int iTable;              /* Cursor number of the source table */
1904     int iColumn;             /* Column number within the source table */
1905     int iSorterColumn;       /* Column number in the sorting index */
1906     int iMem;                /* Memory location that acts as accumulator */
1907     Expr *pExpr;             /* The original expression */
1908   } *aCol;
1909   int nColumn;            /* Number of used entries in aCol[] */
1910   int nAccumulator;       /* Number of columns that show through to the output.
1911                           ** Additional columns are used only as parameters to
1912                           ** aggregate functions */
1913   struct AggInfo_func {   /* For each aggregate function */
1914     Expr *pExpr;             /* Expression encoding the function */
1915     FuncDef *pFunc;          /* The aggregate function implementation */
1916     int iMem;                /* Memory location that acts as accumulator */
1917     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
1918   } *aFunc;
1919   int nFunc;              /* Number of entries in aFunc[] */
1920 };
1921 
1922 /*
1923 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
1924 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
1925 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
1926 ** it uses less memory in the Expr object, which is a big memory user
1927 ** in systems with lots of prepared statements.  And few applications
1928 ** need more than about 10 or 20 variables.  But some extreme users want
1929 ** to have prepared statements with over 32767 variables, and for them
1930 ** the option is available (at compile-time).
1931 */
1932 #if SQLITE_MAX_VARIABLE_NUMBER<=32767
1933 typedef i16 ynVar;
1934 #else
1935 typedef int ynVar;
1936 #endif
1937 
1938 /*
1939 ** Each node of an expression in the parse tree is an instance
1940 ** of this structure.
1941 **
1942 ** Expr.op is the opcode. The integer parser token codes are reused
1943 ** as opcodes here. For example, the parser defines TK_GE to be an integer
1944 ** code representing the ">=" operator. This same integer code is reused
1945 ** to represent the greater-than-or-equal-to operator in the expression
1946 ** tree.
1947 **
1948 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
1949 ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
1950 ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
1951 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
1952 ** then Expr.token contains the name of the function.
1953 **
1954 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
1955 ** binary operator. Either or both may be NULL.
1956 **
1957 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
1958 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
1959 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
1960 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
1961 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
1962 ** valid.
1963 **
1964 ** An expression of the form ID or ID.ID refers to a column in a table.
1965 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
1966 ** the integer cursor number of a VDBE cursor pointing to that table and
1967 ** Expr.iColumn is the column number for the specific column.  If the
1968 ** expression is used as a result in an aggregate SELECT, then the
1969 ** value is also stored in the Expr.iAgg column in the aggregate so that
1970 ** it can be accessed after all aggregates are computed.
1971 **
1972 ** If the expression is an unbound variable marker (a question mark
1973 ** character '?' in the original SQL) then the Expr.iTable holds the index
1974 ** number for that variable.
1975 **
1976 ** If the expression is a subquery then Expr.iColumn holds an integer
1977 ** register number containing the result of the subquery.  If the
1978 ** subquery gives a constant result, then iTable is -1.  If the subquery
1979 ** gives a different answer at different times during statement processing
1980 ** then iTable is the address of a subroutine that computes the subquery.
1981 **
1982 ** If the Expr is of type OP_Column, and the table it is selecting from
1983 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
1984 ** corresponding table definition.
1985 **
1986 ** ALLOCATION NOTES:
1987 **
1988 ** Expr objects can use a lot of memory space in database schema.  To
1989 ** help reduce memory requirements, sometimes an Expr object will be
1990 ** truncated.  And to reduce the number of memory allocations, sometimes
1991 ** two or more Expr objects will be stored in a single memory allocation,
1992 ** together with Expr.zToken strings.
1993 **
1994 ** If the EP_Reduced and EP_TokenOnly flags are set when
1995 ** an Expr object is truncated.  When EP_Reduced is set, then all
1996 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
1997 ** are contained within the same memory allocation.  Note, however, that
1998 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
1999 ** allocated, regardless of whether or not EP_Reduced is set.
2000 */
2001 struct Expr {
2002   u8 op;                 /* Operation performed by this node */
2003   char affinity;         /* The affinity of the column or 0 if not a column */
2004   u32 flags;             /* Various flags.  EP_* See below */
2005   union {
2006     char *zToken;          /* Token value. Zero terminated and dequoted */
2007     int iValue;            /* Non-negative integer value if EP_IntValue */
2008   } u;
2009 
2010   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
2011   ** space is allocated for the fields below this point. An attempt to
2012   ** access them will result in a segfault or malfunction.
2013   *********************************************************************/
2014 
2015   Expr *pLeft;           /* Left subnode */
2016   Expr *pRight;          /* Right subnode */
2017   union {
2018     ExprList *pList;     /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
2019     Select *pSelect;     /* EP_xIsSelect and op = IN, EXISTS, SELECT */
2020   } x;
2021 
2022   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
2023   ** space is allocated for the fields below this point. An attempt to
2024   ** access them will result in a segfault or malfunction.
2025   *********************************************************************/
2026 
2027 #if SQLITE_MAX_EXPR_DEPTH>0
2028   int nHeight;           /* Height of the tree headed by this node */
2029 #endif
2030   int iTable;            /* TK_COLUMN: cursor number of table holding column
2031                          ** TK_REGISTER: register number
2032                          ** TK_TRIGGER: 1 -> new, 0 -> old
2033                          ** EP_Unlikely:  134217728 times likelihood */
2034   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
2035                          ** TK_VARIABLE: variable number (always >= 1). */
2036   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
2037   i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
2038   u8 op2;                /* TK_REGISTER: original value of Expr.op
2039                          ** TK_COLUMN: the value of p5 for OP_Column
2040                          ** TK_AGG_FUNCTION: nesting depth */
2041   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
2042   Table *pTab;           /* Table for TK_COLUMN expressions. */
2043 };
2044 
2045 /*
2046 ** The following are the meanings of bits in the Expr.flags field.
2047 */
2048 #define EP_FromJoin  0x000001 /* Originates in ON/USING clause of outer join */
2049 #define EP_Agg       0x000002 /* Contains one or more aggregate functions */
2050 #define EP_Resolved  0x000004 /* IDs have been resolved to COLUMNs */
2051 #define EP_Error     0x000008 /* Expression contains one or more errors */
2052 #define EP_Distinct  0x000010 /* Aggregate function with DISTINCT keyword */
2053 #define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
2054 #define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
2055 #define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
2056 #define EP_Collate   0x000100 /* Tree contains a TK_COLLATE operator */
2057 #define EP_Generic   0x000200 /* Ignore COLLATE or affinity on this tree */
2058 #define EP_IntValue  0x000400 /* Integer value contained in u.iValue */
2059 #define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
2060 #define EP_Skip      0x001000 /* COLLATE, AS, or UNLIKELY */
2061 #define EP_Reduced   0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
2062 #define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
2063 #define EP_Static    0x008000 /* Held in memory not obtained from malloc() */
2064 #define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
2065 #define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
2066 #define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
2067 #define EP_ConstFunc 0x080000 /* Node is a SQLITE_FUNC_CONSTANT function */
2068 #define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
2069 #define EP_Subquery  0x200000 /* Tree contains a TK_SELECT operator */
2070 
2071 /*
2072 ** Combinations of two or more EP_* flags
2073 */
2074 #define EP_Propagate (EP_Collate|EP_Subquery) /* Propagate these bits up tree */
2075 
2076 /*
2077 ** These macros can be used to test, set, or clear bits in the
2078 ** Expr.flags field.
2079 */
2080 #define ExprHasProperty(E,P)     (((E)->flags&(P))!=0)
2081 #define ExprHasAllProperty(E,P)  (((E)->flags&(P))==(P))
2082 #define ExprSetProperty(E,P)     (E)->flags|=(P)
2083 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
2084 
2085 /* The ExprSetVVAProperty() macro is used for Verification, Validation,
2086 ** and Accreditation only.  It works like ExprSetProperty() during VVA
2087 ** processes but is a no-op for delivery.
2088 */
2089 #ifdef SQLITE_DEBUG
2090 # define ExprSetVVAProperty(E,P)  (E)->flags|=(P)
2091 #else
2092 # define ExprSetVVAProperty(E,P)
2093 #endif
2094 
2095 /*
2096 ** Macros to determine the number of bytes required by a normal Expr
2097 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
2098 ** and an Expr struct with the EP_TokenOnly flag set.
2099 */
2100 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
2101 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
2102 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
2103 
2104 /*
2105 ** Flags passed to the sqlite3ExprDup() function. See the header comment
2106 ** above sqlite3ExprDup() for details.
2107 */
2108 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
2109 
2110 /*
2111 ** A list of expressions.  Each expression may optionally have a
2112 ** name.  An expr/name combination can be used in several ways, such
2113 ** as the list of "expr AS ID" fields following a "SELECT" or in the
2114 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
2115 ** also be used as the argument to a function, in which case the a.zName
2116 ** field is not used.
2117 **
2118 ** By default the Expr.zSpan field holds a human-readable description of
2119 ** the expression that is used in the generation of error messages and
2120 ** column labels.  In this case, Expr.zSpan is typically the text of a
2121 ** column expression as it exists in a SELECT statement.  However, if
2122 ** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
2123 ** of the result column in the form: DATABASE.TABLE.COLUMN.  This later
2124 ** form is used for name resolution with nested FROM clauses.
2125 */
2126 struct ExprList {
2127   int nExpr;             /* Number of expressions on the list */
2128   struct ExprList_item { /* For each expression in the list */
2129     Expr *pExpr;            /* The list of expressions */
2130     char *zName;            /* Token associated with this expression */
2131     char *zSpan;            /* Original text of the expression */
2132     u8 sortOrder;           /* 1 for DESC or 0 for ASC */
2133     unsigned done :1;       /* A flag to indicate when processing is finished */
2134     unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
2135     unsigned reusable :1;   /* Constant expression is reusable */
2136     union {
2137       struct {
2138         u16 iOrderByCol;      /* For ORDER BY, column number in result set */
2139         u16 iAlias;           /* Index into Parse.aAlias[] for zName */
2140       } x;
2141       int iConstExprReg;      /* Register in which Expr value is cached */
2142     } u;
2143   } *a;                  /* Alloc a power of two greater or equal to nExpr */
2144 };
2145 
2146 /*
2147 ** An instance of this structure is used by the parser to record both
2148 ** the parse tree for an expression and the span of input text for an
2149 ** expression.
2150 */
2151 struct ExprSpan {
2152   Expr *pExpr;          /* The expression parse tree */
2153   const char *zStart;   /* First character of input text */
2154   const char *zEnd;     /* One character past the end of input text */
2155 };
2156 
2157 /*
2158 ** An instance of this structure can hold a simple list of identifiers,
2159 ** such as the list "a,b,c" in the following statements:
2160 **
2161 **      INSERT INTO t(a,b,c) VALUES ...;
2162 **      CREATE INDEX idx ON t(a,b,c);
2163 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
2164 **
2165 ** The IdList.a.idx field is used when the IdList represents the list of
2166 ** column names after a table name in an INSERT statement.  In the statement
2167 **
2168 **     INSERT INTO t(a,b,c) ...
2169 **
2170 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
2171 */
2172 struct IdList {
2173   struct IdList_item {
2174     char *zName;      /* Name of the identifier */
2175     int idx;          /* Index in some Table.aCol[] of a column named zName */
2176   } *a;
2177   int nId;         /* Number of identifiers on the list */
2178 };
2179 
2180 /*
2181 ** The bitmask datatype defined below is used for various optimizations.
2182 **
2183 ** Changing this from a 64-bit to a 32-bit type limits the number of
2184 ** tables in a join to 32 instead of 64.  But it also reduces the size
2185 ** of the library by 738 bytes on ix86.
2186 */
2187 typedef u64 Bitmask;
2188 
2189 /*
2190 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
2191 */
2192 #define BMS  ((int)(sizeof(Bitmask)*8))
2193 
2194 /*
2195 ** A bit in a Bitmask
2196 */
2197 #define MASKBIT(n)   (((Bitmask)1)<<(n))
2198 #define MASKBIT32(n) (((unsigned int)1)<<(n))
2199 
2200 /*
2201 ** The following structure describes the FROM clause of a SELECT statement.
2202 ** Each table or subquery in the FROM clause is a separate element of
2203 ** the SrcList.a[] array.
2204 **
2205 ** With the addition of multiple database support, the following structure
2206 ** can also be used to describe a particular table such as the table that
2207 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
2208 ** such a table must be a simple name: ID.  But in SQLite, the table can
2209 ** now be identified by a database name, a dot, then the table name: ID.ID.
2210 **
2211 ** The jointype starts out showing the join type between the current table
2212 ** and the next table on the list.  The parser builds the list this way.
2213 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
2214 ** jointype expresses the join between the table and the previous table.
2215 **
2216 ** In the colUsed field, the high-order bit (bit 63) is set if the table
2217 ** contains more than 63 columns and the 64-th or later column is used.
2218 */
2219 struct SrcList {
2220   int nSrc;        /* Number of tables or subqueries in the FROM clause */
2221   u32 nAlloc;      /* Number of entries allocated in a[] below */
2222   struct SrcList_item {
2223     Schema *pSchema;  /* Schema to which this item is fixed */
2224     char *zDatabase;  /* Name of database holding this table */
2225     char *zName;      /* Name of the table */
2226     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
2227     Table *pTab;      /* An SQL table corresponding to zName */
2228     Select *pSelect;  /* A SELECT statement used in place of a table name */
2229     int addrFillSub;  /* Address of subroutine to manifest a subquery */
2230     int regReturn;    /* Register holding return address of addrFillSub */
2231     int regResult;    /* Registers holding results of a co-routine */
2232     u8 jointype;      /* Type of join between this able and the previous */
2233     unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
2234     unsigned isCorrelated :1;  /* True if sub-query is correlated */
2235     unsigned viaCoroutine :1;  /* Implemented as a co-routine */
2236     unsigned isRecursive :1;   /* True for recursive reference in WITH */
2237 #ifndef SQLITE_OMIT_EXPLAIN
2238     u8 iSelectId;     /* If pSelect!=0, the id of the sub-select in EQP */
2239 #endif
2240     int iCursor;      /* The VDBE cursor number used to access this table */
2241     Expr *pOn;        /* The ON clause of a join */
2242     IdList *pUsing;   /* The USING clause of a join */
2243     Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
2244     char *zIndex;     /* Identifier from "INDEXED BY <zIndex>" clause */
2245     Index *pIndex;    /* Index structure corresponding to zIndex, if any */
2246   } a[1];             /* One entry for each identifier on the list */
2247 };
2248 
2249 /*
2250 ** Permitted values of the SrcList.a.jointype field
2251 */
2252 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
2253 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
2254 #define JT_NATURAL   0x0004    /* True for a "natural" join */
2255 #define JT_LEFT      0x0008    /* Left outer join */
2256 #define JT_RIGHT     0x0010    /* Right outer join */
2257 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
2258 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
2259 
2260 
2261 /*
2262 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
2263 ** and the WhereInfo.wctrlFlags member.
2264 */
2265 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
2266 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
2267 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
2268 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
2269 #define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
2270 #define WHERE_OMIT_OPEN_CLOSE  0x0010 /* Table cursors are already open */
2271 #define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
2272 #define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
2273 #define WHERE_NO_AUTOINDEX     0x0080 /* Disallow automatic indexes */
2274 #define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
2275 #define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
2276 #define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
2277 #define WHERE_SORTBYGROUP      0x0800 /* Support sqlite3WhereIsSorted() */
2278 #define WHERE_REOPEN_IDX       0x1000 /* Try to use OP_ReopenIdx */
2279 
2280 /* Allowed return values from sqlite3WhereIsDistinct()
2281 */
2282 #define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
2283 #define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
2284 #define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
2285 #define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
2286 
2287 /*
2288 ** A NameContext defines a context in which to resolve table and column
2289 ** names.  The context consists of a list of tables (the pSrcList) field and
2290 ** a list of named expression (pEList).  The named expression list may
2291 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
2292 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
2293 ** pEList corresponds to the result set of a SELECT and is NULL for
2294 ** other statements.
2295 **
2296 ** NameContexts can be nested.  When resolving names, the inner-most
2297 ** context is searched first.  If no match is found, the next outer
2298 ** context is checked.  If there is still no match, the next context
2299 ** is checked.  This process continues until either a match is found
2300 ** or all contexts are check.  When a match is found, the nRef member of
2301 ** the context containing the match is incremented.
2302 **
2303 ** Each subquery gets a new NameContext.  The pNext field points to the
2304 ** NameContext in the parent query.  Thus the process of scanning the
2305 ** NameContext list corresponds to searching through successively outer
2306 ** subqueries looking for a match.
2307 */
2308 struct NameContext {
2309   Parse *pParse;       /* The parser */
2310   SrcList *pSrcList;   /* One or more tables used to resolve names */
2311   ExprList *pEList;    /* Optional list of result-set columns */
2312   AggInfo *pAggInfo;   /* Information about aggregates at this level */
2313   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
2314   int nRef;            /* Number of names resolved by this context */
2315   int nErr;            /* Number of errors encountered while resolving names */
2316   u16 ncFlags;         /* Zero or more NC_* flags defined below */
2317 };
2318 
2319 /*
2320 ** Allowed values for the NameContext, ncFlags field.
2321 **
2322 ** Note:  NC_MinMaxAgg must have the same value as SF_MinMaxAgg and
2323 ** SQLITE_FUNC_MINMAX.
2324 **
2325 */
2326 #define NC_AllowAgg  0x0001  /* Aggregate functions are allowed here */
2327 #define NC_HasAgg    0x0002  /* One or more aggregate functions seen */
2328 #define NC_IsCheck   0x0004  /* True if resolving names in a CHECK constraint */
2329 #define NC_InAggFunc 0x0008  /* True if analyzing arguments to an agg func */
2330 #define NC_PartIdx   0x0010  /* True if resolving a partial index WHERE */
2331 #define NC_MinMaxAgg 0x1000  /* min/max aggregates seen.  See note above */
2332 
2333 /*
2334 ** An instance of the following structure contains all information
2335 ** needed to generate code for a single SELECT statement.
2336 **
2337 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
2338 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
2339 ** limit and nOffset to the value of the offset (or 0 if there is not
2340 ** offset).  But later on, nLimit and nOffset become the memory locations
2341 ** in the VDBE that record the limit and offset counters.
2342 **
2343 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
2344 ** These addresses must be stored so that we can go back and fill in
2345 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
2346 ** the number of columns in P2 can be computed at the same time
2347 ** as the OP_OpenEphm instruction is coded because not
2348 ** enough information about the compound query is known at that point.
2349 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
2350 ** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
2351 ** sequences for the ORDER BY clause.
2352 */
2353 struct Select {
2354   ExprList *pEList;      /* The fields of the result */
2355   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
2356   u16 selFlags;          /* Various SF_* values */
2357   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
2358 #if SELECTTRACE_ENABLED
2359   char zSelName[12];     /* Symbolic name of this SELECT use for debugging */
2360 #endif
2361   int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
2362   u64 nSelectRow;        /* Estimated number of result rows */
2363   SrcList *pSrc;         /* The FROM clause */
2364   Expr *pWhere;          /* The WHERE clause */
2365   ExprList *pGroupBy;    /* The GROUP BY clause */
2366   Expr *pHaving;         /* The HAVING clause */
2367   ExprList *pOrderBy;    /* The ORDER BY clause */
2368   Select *pPrior;        /* Prior select in a compound select statement */
2369   Select *pNext;         /* Next select to the left in a compound */
2370   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
2371   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
2372   With *pWith;           /* WITH clause attached to this select. Or NULL. */
2373 };
2374 
2375 /*
2376 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
2377 ** "Select Flag".
2378 */
2379 #define SF_Distinct        0x0001  /* Output should be DISTINCT */
2380 #define SF_Resolved        0x0002  /* Identifiers have been resolved */
2381 #define SF_Aggregate       0x0004  /* Contains aggregate functions */
2382 #define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
2383 #define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
2384 #define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
2385 #define SF_Compound        0x0040  /* Part of a compound query */
2386 #define SF_Values          0x0080  /* Synthesized from VALUES clause */
2387 #define SF_AllValues       0x0100  /* All terms of compound are VALUES */
2388 #define SF_NestedFrom      0x0200  /* Part of a parenthesized FROM clause */
2389 #define SF_MaybeConvert    0x0400  /* Need convertCompoundSelectToSubquery() */
2390 #define SF_Recursive       0x0800  /* The recursive part of a recursive CTE */
2391 #define SF_MinMaxAgg       0x1000  /* Aggregate containing min() or max() */
2392 
2393 
2394 /*
2395 ** The results of a SELECT can be distributed in several ways, as defined
2396 ** by one of the following macros.  The "SRT" prefix means "SELECT Result
2397 ** Type".
2398 **
2399 **     SRT_Union       Store results as a key in a temporary index
2400 **                     identified by pDest->iSDParm.
2401 **
2402 **     SRT_Except      Remove results from the temporary index pDest->iSDParm.
2403 **
2404 **     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
2405 **                     set is not empty.
2406 **
2407 **     SRT_Discard     Throw the results away.  This is used by SELECT
2408 **                     statements within triggers whose only purpose is
2409 **                     the side-effects of functions.
2410 **
2411 ** All of the above are free to ignore their ORDER BY clause. Those that
2412 ** follow must honor the ORDER BY clause.
2413 **
2414 **     SRT_Output      Generate a row of output (using the OP_ResultRow
2415 **                     opcode) for each row in the result set.
2416 **
2417 **     SRT_Mem         Only valid if the result is a single column.
2418 **                     Store the first column of the first result row
2419 **                     in register pDest->iSDParm then abandon the rest
2420 **                     of the query.  This destination implies "LIMIT 1".
2421 **
2422 **     SRT_Set         The result must be a single column.  Store each
2423 **                     row of result as the key in table pDest->iSDParm.
2424 **                     Apply the affinity pDest->affSdst before storing
2425 **                     results.  Used to implement "IN (SELECT ...)".
2426 **
2427 **     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
2428 **                     the result there. The cursor is left open after
2429 **                     returning.  This is like SRT_Table except that
2430 **                     this destination uses OP_OpenEphemeral to create
2431 **                     the table first.
2432 **
2433 **     SRT_Coroutine   Generate a co-routine that returns a new row of
2434 **                     results each time it is invoked.  The entry point
2435 **                     of the co-routine is stored in register pDest->iSDParm
2436 **                     and the result row is stored in pDest->nDest registers
2437 **                     starting with pDest->iSdst.
2438 **
2439 **     SRT_Table       Store results in temporary table pDest->iSDParm.
2440 **     SRT_Fifo        This is like SRT_EphemTab except that the table
2441 **                     is assumed to already be open.  SRT_Fifo has
2442 **                     the additional property of being able to ignore
2443 **                     the ORDER BY clause.
2444 **
2445 **     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
2446 **                     But also use temporary table pDest->iSDParm+1 as
2447 **                     a record of all prior results and ignore any duplicate
2448 **                     rows.  Name means:  "Distinct Fifo".
2449 **
2450 **     SRT_Queue       Store results in priority queue pDest->iSDParm (really
2451 **                     an index).  Append a sequence number so that all entries
2452 **                     are distinct.
2453 **
2454 **     SRT_DistQueue   Store results in priority queue pDest->iSDParm only if
2455 **                     the same record has never been stored before.  The
2456 **                     index at pDest->iSDParm+1 hold all prior stores.
2457 */
2458 #define SRT_Union        1  /* Store result as keys in an index */
2459 #define SRT_Except       2  /* Remove result from a UNION index */
2460 #define SRT_Exists       3  /* Store 1 if the result is not empty */
2461 #define SRT_Discard      4  /* Do not save the results anywhere */
2462 #define SRT_Fifo         5  /* Store result as data with an automatic rowid */
2463 #define SRT_DistFifo     6  /* Like SRT_Fifo, but unique results only */
2464 #define SRT_Queue        7  /* Store result in an queue */
2465 #define SRT_DistQueue    8  /* Like SRT_Queue, but unique results only */
2466 
2467 /* The ORDER BY clause is ignored for all of the above */
2468 #define IgnorableOrderby(X) ((X->eDest)<=SRT_DistQueue)
2469 
2470 #define SRT_Output       9  /* Output each row of result */
2471 #define SRT_Mem         10  /* Store result in a memory cell */
2472 #define SRT_Set         11  /* Store results as keys in an index */
2473 #define SRT_EphemTab    12  /* Create transient tab and store like SRT_Table */
2474 #define SRT_Coroutine   13  /* Generate a single row of result */
2475 #define SRT_Table       14  /* Store result as data with an automatic rowid */
2476 
2477 /*
2478 ** An instance of this object describes where to put of the results of
2479 ** a SELECT statement.
2480 */
2481 struct SelectDest {
2482   u8 eDest;            /* How to dispose of the results.  On of SRT_* above. */
2483   char affSdst;        /* Affinity used when eDest==SRT_Set */
2484   int iSDParm;         /* A parameter used by the eDest disposal method */
2485   int iSdst;           /* Base register where results are written */
2486   int nSdst;           /* Number of registers allocated */
2487   ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
2488 };
2489 
2490 /*
2491 ** During code generation of statements that do inserts into AUTOINCREMENT
2492 ** tables, the following information is attached to the Table.u.autoInc.p
2493 ** pointer of each autoincrement table to record some side information that
2494 ** the code generator needs.  We have to keep per-table autoincrement
2495 ** information in case inserts are down within triggers.  Triggers do not
2496 ** normally coordinate their activities, but we do need to coordinate the
2497 ** loading and saving of autoincrement information.
2498 */
2499 struct AutoincInfo {
2500   AutoincInfo *pNext;   /* Next info block in a list of them all */
2501   Table *pTab;          /* Table this info block refers to */
2502   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
2503   int regCtr;           /* Memory register holding the rowid counter */
2504 };
2505 
2506 /*
2507 ** Size of the column cache
2508 */
2509 #ifndef SQLITE_N_COLCACHE
2510 # define SQLITE_N_COLCACHE 10
2511 #endif
2512 
2513 /*
2514 ** At least one instance of the following structure is created for each
2515 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
2516 ** statement. All such objects are stored in the linked list headed at
2517 ** Parse.pTriggerPrg and deleted once statement compilation has been
2518 ** completed.
2519 **
2520 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
2521 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
2522 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
2523 ** The Parse.pTriggerPrg list never contains two entries with the same
2524 ** values for both pTrigger and orconf.
2525 **
2526 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
2527 ** accessed (or set to 0 for triggers fired as a result of INSERT
2528 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
2529 ** a mask of new.* columns used by the program.
2530 */
2531 struct TriggerPrg {
2532   Trigger *pTrigger;      /* Trigger this program was coded from */
2533   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
2534   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
2535   int orconf;             /* Default ON CONFLICT policy */
2536   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
2537 };
2538 
2539 /*
2540 ** The yDbMask datatype for the bitmask of all attached databases.
2541 */
2542 #if SQLITE_MAX_ATTACHED>30
2543   typedef unsigned char yDbMask[(SQLITE_MAX_ATTACHED+9)/8];
2544 # define DbMaskTest(M,I)    (((M)[(I)/8]&(1<<((I)&7)))!=0)
2545 # define DbMaskZero(M)      memset((M),0,sizeof(M))
2546 # define DbMaskSet(M,I)     (M)[(I)/8]|=(1<<((I)&7))
2547 # define DbMaskAllZero(M)   sqlite3DbMaskAllZero(M)
2548 # define DbMaskNonZero(M)   (sqlite3DbMaskAllZero(M)==0)
2549 #else
2550   typedef unsigned int yDbMask;
2551 # define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
2552 # define DbMaskZero(M)      (M)=0
2553 # define DbMaskSet(M,I)     (M)|=(((yDbMask)1)<<(I))
2554 # define DbMaskAllZero(M)   (M)==0
2555 # define DbMaskNonZero(M)   (M)!=0
2556 #endif
2557 
2558 /*
2559 ** An SQL parser context.  A copy of this structure is passed through
2560 ** the parser and down into all the parser action routine in order to
2561 ** carry around information that is global to the entire parse.
2562 **
2563 ** The structure is divided into two parts.  When the parser and code
2564 ** generate call themselves recursively, the first part of the structure
2565 ** is constant but the second part is reset at the beginning and end of
2566 ** each recursion.
2567 **
2568 ** The nTableLock and aTableLock variables are only used if the shared-cache
2569 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
2570 ** used to store the set of table-locks required by the statement being
2571 ** compiled. Function sqlite3TableLock() is used to add entries to the
2572 ** list.
2573 */
2574 struct Parse {
2575   sqlite3 *db;         /* The main database structure */
2576   char *zErrMsg;       /* An error message */
2577   Vdbe *pVdbe;         /* An engine for executing database bytecode */
2578   int rc;              /* Return code from execution */
2579   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
2580   u8 checkSchema;      /* Causes schema cookie check after an error */
2581   u8 nested;           /* Number of nested calls to the parser/code generator */
2582   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
2583   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
2584   u8 mayAbort;         /* True if statement may throw an ABORT exception */
2585   u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
2586   u8 okConstFactor;    /* OK to factor out constants */
2587   int aTempReg[8];     /* Holding area for temporary registers */
2588   int nRangeReg;       /* Size of the temporary register block */
2589   int iRangeReg;       /* First register in temporary register block */
2590   int nErr;            /* Number of errors seen */
2591   int nTab;            /* Number of previously allocated VDBE cursors */
2592   int nMem;            /* Number of memory cells used so far */
2593   int nSet;            /* Number of sets used so far */
2594   int nOnce;           /* Number of OP_Once instructions so far */
2595   int nOpAlloc;        /* Number of slots allocated for Vdbe.aOp[] */
2596   int iFixedOp;        /* Never back out opcodes iFixedOp-1 or earlier */
2597   int ckBase;          /* Base register of data during check constraints */
2598   int iPartIdxTab;     /* Table corresponding to a partial index */
2599   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
2600   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
2601   int nLabel;          /* Number of labels used */
2602   int *aLabel;         /* Space to hold the labels */
2603   struct yColCache {
2604     int iTable;           /* Table cursor number */
2605     i16 iColumn;          /* Table column number */
2606     u8 tempReg;           /* iReg is a temp register that needs to be freed */
2607     int iLevel;           /* Nesting level */
2608     int iReg;             /* Reg with value of this column. 0 means none. */
2609     int lru;              /* Least recently used entry has the smallest value */
2610   } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
2611   ExprList *pConstExpr;/* Constant expressions */
2612   Token constraintName;/* Name of the constraint currently being parsed */
2613   yDbMask writeMask;   /* Start a write transaction on these databases */
2614   yDbMask cookieMask;  /* Bitmask of schema verified databases */
2615   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
2616   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
2617   int regRoot;         /* Register holding root page number for new objects */
2618   int nMaxArg;         /* Max args passed to user function by sub-program */
2619 #if SELECTTRACE_ENABLED
2620   int nSelect;         /* Number of SELECT statements seen */
2621   int nSelectIndent;   /* How far to indent SELECTTRACE() output */
2622 #endif
2623 #ifndef SQLITE_OMIT_SHARED_CACHE
2624   int nTableLock;        /* Number of locks in aTableLock */
2625   TableLock *aTableLock; /* Required table locks for shared-cache mode */
2626 #endif
2627   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
2628 
2629   /* Information used while coding trigger programs. */
2630   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
2631   Table *pTriggerTab;  /* Table triggers are being coded for */
2632   int addrCrTab;       /* Address of OP_CreateTable opcode on CREATE TABLE */
2633   int addrSkipPK;      /* Address of instruction to skip PRIMARY KEY index */
2634   u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
2635   u32 oldmask;         /* Mask of old.* columns referenced */
2636   u32 newmask;         /* Mask of new.* columns referenced */
2637   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
2638   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
2639   u8 disableTriggers;  /* True to disable triggers */
2640 
2641   /************************************************************************
2642   ** Above is constant between recursions.  Below is reset before and after
2643   ** each recursion.  The boundary between these two regions is determined
2644   ** using offsetof(Parse,nVar) so the nVar field must be the first field
2645   ** in the recursive region.
2646   ************************************************************************/
2647 
2648   int nVar;                 /* Number of '?' variables seen in the SQL so far */
2649   int nzVar;                /* Number of available slots in azVar[] */
2650   u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
2651   u8 bFreeWith;             /* True if pWith should be freed with parser */
2652   u8 explain;               /* True if the EXPLAIN flag is found on the query */
2653 #ifndef SQLITE_OMIT_VIRTUALTABLE
2654   u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
2655   int nVtabLock;            /* Number of virtual tables to lock */
2656 #endif
2657   int nAlias;               /* Number of aliased result set columns */
2658   int nHeight;              /* Expression tree height of current sub-select */
2659 #ifndef SQLITE_OMIT_EXPLAIN
2660   int iSelectId;            /* ID of current select for EXPLAIN output */
2661   int iNextSelectId;        /* Next available select ID for EXPLAIN output */
2662 #endif
2663   char **azVar;             /* Pointers to names of parameters */
2664   Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
2665   const char *zTail;        /* All SQL text past the last semicolon parsed */
2666   Table *pNewTable;         /* A table being constructed by CREATE TABLE */
2667   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
2668   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
2669   Token sNameToken;         /* Token with unqualified schema object name */
2670   Token sLastToken;         /* The last token parsed */
2671 #ifndef SQLITE_OMIT_VIRTUALTABLE
2672   Token sArg;               /* Complete text of a module argument */
2673   Table **apVtabLock;       /* Pointer to virtual tables needing locking */
2674 #endif
2675   Table *pZombieTab;        /* List of Table objects to delete after code gen */
2676   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
2677   With *pWith;              /* Current WITH clause, or NULL */
2678 };
2679 
2680 /*
2681 ** Return true if currently inside an sqlite3_declare_vtab() call.
2682 */
2683 #ifdef SQLITE_OMIT_VIRTUALTABLE
2684   #define IN_DECLARE_VTAB 0
2685 #else
2686   #define IN_DECLARE_VTAB (pParse->declareVtab)
2687 #endif
2688 
2689 /*
2690 ** An instance of the following structure can be declared on a stack and used
2691 ** to save the Parse.zAuthContext value so that it can be restored later.
2692 */
2693 struct AuthContext {
2694   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
2695   Parse *pParse;              /* The Parse structure */
2696 };
2697 
2698 /*
2699 ** Bitfield flags for P5 value in various opcodes.
2700 */
2701 #define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
2702 #define OPFLAG_EPHEM         0x01    /* OP_Column: Ephemeral output is ok */
2703 #define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
2704 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
2705 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
2706 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
2707 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
2708 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
2709 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
2710 #define OPFLAG_SEEKEQ        0x02    /* OP_Open** cursor uses EQ seek only */
2711 #define OPFLAG_P2ISREG       0x04    /* P2 to OP_Open** is a register number */
2712 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
2713 
2714 /*
2715  * Each trigger present in the database schema is stored as an instance of
2716  * struct Trigger.
2717  *
2718  * Pointers to instances of struct Trigger are stored in two ways.
2719  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
2720  *    database). This allows Trigger structures to be retrieved by name.
2721  * 2. All triggers associated with a single table form a linked list, using the
2722  *    pNext member of struct Trigger. A pointer to the first element of the
2723  *    linked list is stored as the "pTrigger" member of the associated
2724  *    struct Table.
2725  *
2726  * The "step_list" member points to the first element of a linked list
2727  * containing the SQL statements specified as the trigger program.
2728  */
2729 struct Trigger {
2730   char *zName;            /* The name of the trigger                        */
2731   char *table;            /* The table or view to which the trigger applies */
2732   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
2733   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
2734   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
2735   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
2736                              the <column-list> is stored here */
2737   Schema *pSchema;        /* Schema containing the trigger */
2738   Schema *pTabSchema;     /* Schema containing the table */
2739   TriggerStep *step_list; /* Link list of trigger program steps             */
2740   Trigger *pNext;         /* Next trigger associated with the table */
2741 };
2742 
2743 /*
2744 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
2745 ** determine which.
2746 **
2747 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
2748 ** In that cases, the constants below can be ORed together.
2749 */
2750 #define TRIGGER_BEFORE  1
2751 #define TRIGGER_AFTER   2
2752 
2753 /*
2754  * An instance of struct TriggerStep is used to store a single SQL statement
2755  * that is a part of a trigger-program.
2756  *
2757  * Instances of struct TriggerStep are stored in a singly linked list (linked
2758  * using the "pNext" member) referenced by the "step_list" member of the
2759  * associated struct Trigger instance. The first element of the linked list is
2760  * the first step of the trigger-program.
2761  *
2762  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
2763  * "SELECT" statement. The meanings of the other members is determined by the
2764  * value of "op" as follows:
2765  *
2766  * (op == TK_INSERT)
2767  * orconf    -> stores the ON CONFLICT algorithm
2768  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
2769  *              this stores a pointer to the SELECT statement. Otherwise NULL.
2770  * target    -> A token holding the quoted name of the table to insert into.
2771  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
2772  *              this stores values to be inserted. Otherwise NULL.
2773  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
2774  *              statement, then this stores the column-names to be
2775  *              inserted into.
2776  *
2777  * (op == TK_DELETE)
2778  * target    -> A token holding the quoted name of the table to delete from.
2779  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
2780  *              Otherwise NULL.
2781  *
2782  * (op == TK_UPDATE)
2783  * target    -> A token holding the quoted name of the table to update rows of.
2784  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
2785  *              Otherwise NULL.
2786  * pExprList -> A list of the columns to update and the expressions to update
2787  *              them to. See sqlite3Update() documentation of "pChanges"
2788  *              argument.
2789  *
2790  */
2791 struct TriggerStep {
2792   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
2793   u8 orconf;           /* OE_Rollback etc. */
2794   Trigger *pTrig;      /* The trigger that this step is a part of */
2795   Select *pSelect;     /* SELECT statment or RHS of INSERT INTO .. SELECT ... */
2796   Token target;        /* Target table for DELETE, UPDATE, INSERT */
2797   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
2798   ExprList *pExprList; /* SET clause for UPDATE. */
2799   IdList *pIdList;     /* Column names for INSERT */
2800   TriggerStep *pNext;  /* Next in the link-list */
2801   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
2802 };
2803 
2804 /*
2805 ** The following structure contains information used by the sqliteFix...
2806 ** routines as they walk the parse tree to make database references
2807 ** explicit.
2808 */
2809 typedef struct DbFixer DbFixer;
2810 struct DbFixer {
2811   Parse *pParse;      /* The parsing context.  Error messages written here */
2812   Schema *pSchema;    /* Fix items to this schema */
2813   int bVarOnly;       /* Check for variable references only */
2814   const char *zDb;    /* Make sure all objects are contained in this database */
2815   const char *zType;  /* Type of the container - used for error messages */
2816   const Token *pName; /* Name of the container - used for error messages */
2817 };
2818 
2819 /*
2820 ** An objected used to accumulate the text of a string where we
2821 ** do not necessarily know how big the string will be in the end.
2822 */
2823 struct StrAccum {
2824   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
2825   char *zBase;         /* A base allocation.  Not from malloc. */
2826   char *zText;         /* The string collected so far */
2827   int  nChar;          /* Length of the string so far */
2828   int  nAlloc;         /* Amount of space allocated in zText */
2829   int  mxAlloc;        /* Maximum allowed string length */
2830   u8   useMalloc;      /* 0: none,  1: sqlite3DbMalloc,  2: sqlite3_malloc */
2831   u8   accError;       /* STRACCUM_NOMEM or STRACCUM_TOOBIG */
2832 };
2833 #define STRACCUM_NOMEM   1
2834 #define STRACCUM_TOOBIG  2
2835 
2836 /*
2837 ** A pointer to this structure is used to communicate information
2838 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
2839 */
2840 typedef struct {
2841   sqlite3 *db;        /* The database being initialized */
2842   char **pzErrMsg;    /* Error message stored here */
2843   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
2844   int rc;             /* Result code stored here */
2845 } InitData;
2846 
2847 /*
2848 ** Structure containing global configuration data for the SQLite library.
2849 **
2850 ** This structure also contains some state information.
2851 */
2852 struct Sqlite3Config {
2853   int bMemstat;                     /* True to enable memory status */
2854   int bCoreMutex;                   /* True to enable core mutexing */
2855   int bFullMutex;                   /* True to enable full mutexing */
2856   int bOpenUri;                     /* True to interpret filenames as URIs */
2857   int bUseCis;                      /* Use covering indices for full-scans */
2858   int mxStrlen;                     /* Maximum string length */
2859   int neverCorrupt;                 /* Database is always well-formed */
2860   int szLookaside;                  /* Default lookaside buffer size */
2861   int nLookaside;                   /* Default lookaside buffer count */
2862   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
2863   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
2864   sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
2865   void *pHeap;                      /* Heap storage space */
2866   int nHeap;                        /* Size of pHeap[] */
2867   int mnReq, mxReq;                 /* Min and max heap requests sizes */
2868   sqlite3_int64 szMmap;             /* mmap() space per open file */
2869   sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
2870   void *pScratch;                   /* Scratch memory */
2871   int szScratch;                    /* Size of each scratch buffer */
2872   int nScratch;                     /* Number of scratch buffers */
2873   void *pPage;                      /* Page cache memory */
2874   int szPage;                       /* Size of each page in pPage[] */
2875   int nPage;                        /* Number of pages in pPage[] */
2876   int mxParserStack;                /* maximum depth of the parser stack */
2877   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
2878   u32 szPma;                        /* Maximum Sorter PMA size */
2879   /* The above might be initialized to non-zero.  The following need to always
2880   ** initially be zero, however. */
2881   int isInit;                       /* True after initialization has finished */
2882   int inProgress;                   /* True while initialization in progress */
2883   int isMutexInit;                  /* True after mutexes are initialized */
2884   int isMallocInit;                 /* True after malloc is initialized */
2885   int isPCacheInit;                 /* True after malloc is initialized */
2886   int nRefInitMutex;                /* Number of users of pInitMutex */
2887   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
2888   void (*xLog)(void*,int,const char*); /* Function for logging */
2889   void *pLogArg;                       /* First argument to xLog() */
2890 #ifdef SQLITE_ENABLE_SQLLOG
2891   void(*xSqllog)(void*,sqlite3*,const char*, int);
2892   void *pSqllogArg;
2893 #endif
2894 #ifdef SQLITE_VDBE_COVERAGE
2895   /* The following callback (if not NULL) is invoked on every VDBE branch
2896   ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
2897   */
2898   void (*xVdbeBranch)(void*,int iSrcLine,u8 eThis,u8 eMx);  /* Callback */
2899   void *pVdbeBranchArg;                                     /* 1st argument */
2900 #endif
2901 #ifndef SQLITE_OMIT_BUILTIN_TEST
2902   int (*xTestCallback)(int);        /* Invoked by sqlite3FaultSim() */
2903 #endif
2904   int bLocaltimeFault;              /* True to fail localtime() calls */
2905 };
2906 
2907 /*
2908 ** This macro is used inside of assert() statements to indicate that
2909 ** the assert is only valid on a well-formed database.  Instead of:
2910 **
2911 **     assert( X );
2912 **
2913 ** One writes:
2914 **
2915 **     assert( X || CORRUPT_DB );
2916 **
2917 ** CORRUPT_DB is true during normal operation.  CORRUPT_DB does not indicate
2918 ** that the database is definitely corrupt, only that it might be corrupt.
2919 ** For most test cases, CORRUPT_DB is set to false using a special
2920 ** sqlite3_test_control().  This enables assert() statements to prove
2921 ** things that are always true for well-formed databases.
2922 */
2923 #define CORRUPT_DB  (sqlite3Config.neverCorrupt==0)
2924 
2925 /*
2926 ** Context pointer passed down through the tree-walk.
2927 */
2928 struct Walker {
2929   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
2930   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
2931   void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
2932   Parse *pParse;                            /* Parser context.  */
2933   int walkerDepth;                          /* Number of subqueries */
2934   u8 eCode;                                 /* A small processing code */
2935   union {                                   /* Extra data for callback */
2936     NameContext *pNC;                          /* Naming context */
2937     int n;                                     /* A counter */
2938     int iCur;                                  /* A cursor number */
2939     SrcList *pSrcList;                         /* FROM clause */
2940     struct SrcCount *pSrcCount;                /* Counting column references */
2941   } u;
2942 };
2943 
2944 /* Forward declarations */
2945 int sqlite3WalkExpr(Walker*, Expr*);
2946 int sqlite3WalkExprList(Walker*, ExprList*);
2947 int sqlite3WalkSelect(Walker*, Select*);
2948 int sqlite3WalkSelectExpr(Walker*, Select*);
2949 int sqlite3WalkSelectFrom(Walker*, Select*);
2950 
2951 /*
2952 ** Return code from the parse-tree walking primitives and their
2953 ** callbacks.
2954 */
2955 #define WRC_Continue    0   /* Continue down into children */
2956 #define WRC_Prune       1   /* Omit children but continue walking siblings */
2957 #define WRC_Abort       2   /* Abandon the tree walk */
2958 
2959 /*
2960 ** An instance of this structure represents a set of one or more CTEs
2961 ** (common table expressions) created by a single WITH clause.
2962 */
2963 struct With {
2964   int nCte;                       /* Number of CTEs in the WITH clause */
2965   With *pOuter;                   /* Containing WITH clause, or NULL */
2966   struct Cte {                    /* For each CTE in the WITH clause.... */
2967     char *zName;                    /* Name of this CTE */
2968     ExprList *pCols;                /* List of explicit column names, or NULL */
2969     Select *pSelect;                /* The definition of this CTE */
2970     const char *zErr;               /* Error message for circular references */
2971   } a[1];
2972 };
2973 
2974 #ifdef SQLITE_DEBUG
2975 /*
2976 ** An instance of the TreeView object is used for printing the content of
2977 ** data structures on sqlite3DebugPrintf() using a tree-like view.
2978 */
2979 struct TreeView {
2980   int iLevel;             /* Which level of the tree we are on */
2981   u8  bLine[100];         /* Draw vertical in column i if bLine[i] is true */
2982 };
2983 #endif /* SQLITE_DEBUG */
2984 
2985 /*
2986 ** Assuming zIn points to the first byte of a UTF-8 character,
2987 ** advance zIn to point to the first byte of the next UTF-8 character.
2988 */
2989 #define SQLITE_SKIP_UTF8(zIn) {                        \
2990   if( (*(zIn++))>=0xc0 ){                              \
2991     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
2992   }                                                    \
2993 }
2994 
2995 /*
2996 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
2997 ** the same name but without the _BKPT suffix.  These macros invoke
2998 ** routines that report the line-number on which the error originated
2999 ** using sqlite3_log().  The routines also provide a convenient place
3000 ** to set a debugger breakpoint.
3001 */
3002 int sqlite3CorruptError(int);
3003 int sqlite3MisuseError(int);
3004 int sqlite3CantopenError(int);
3005 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
3006 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
3007 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
3008 
3009 
3010 /*
3011 ** FTS4 is really an extension for FTS3.  It is enabled using the
3012 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also call
3013 ** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
3014 */
3015 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
3016 # define SQLITE_ENABLE_FTS3 1
3017 #endif
3018 
3019 /*
3020 ** The ctype.h header is needed for non-ASCII systems.  It is also
3021 ** needed by FTS3 when FTS3 is included in the amalgamation.
3022 */
3023 #if !defined(SQLITE_ASCII) || \
3024     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
3025 # include <ctype.h>
3026 #endif
3027 
3028 /*
3029 ** The following macros mimic the standard library functions toupper(),
3030 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
3031 ** sqlite versions only work for ASCII characters, regardless of locale.
3032 */
3033 #ifdef SQLITE_ASCII
3034 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
3035 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
3036 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
3037 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
3038 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
3039 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
3040 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
3041 #else
3042 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
3043 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
3044 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
3045 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
3046 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
3047 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
3048 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
3049 #endif
3050 int sqlite3IsIdChar(u8);
3051 
3052 /*
3053 ** Internal function prototypes
3054 */
3055 #define sqlite3StrICmp sqlite3_stricmp
3056 int sqlite3Strlen30(const char*);
3057 #define sqlite3StrNICmp sqlite3_strnicmp
3058 
3059 int sqlite3MallocInit(void);
3060 void sqlite3MallocEnd(void);
3061 void *sqlite3Malloc(u64);
3062 void *sqlite3MallocZero(u64);
3063 void *sqlite3DbMallocZero(sqlite3*, u64);
3064 void *sqlite3DbMallocRaw(sqlite3*, u64);
3065 char *sqlite3DbStrDup(sqlite3*,const char*);
3066 char *sqlite3DbStrNDup(sqlite3*,const char*, u64);
3067 void *sqlite3Realloc(void*, u64);
3068 void *sqlite3DbReallocOrFree(sqlite3 *, void *, u64);
3069 void *sqlite3DbRealloc(sqlite3 *, void *, u64);
3070 void sqlite3DbFree(sqlite3*, void*);
3071 int sqlite3MallocSize(void*);
3072 int sqlite3DbMallocSize(sqlite3*, void*);
3073 void *sqlite3ScratchMalloc(int);
3074 void sqlite3ScratchFree(void*);
3075 void *sqlite3PageMalloc(int);
3076 void sqlite3PageFree(void*);
3077 void sqlite3MemSetDefault(void);
3078 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
3079 int sqlite3HeapNearlyFull(void);
3080 
3081 /*
3082 ** On systems with ample stack space and that support alloca(), make
3083 ** use of alloca() to obtain space for large automatic objects.  By default,
3084 ** obtain space from malloc().
3085 **
3086 ** The alloca() routine never returns NULL.  This will cause code paths
3087 ** that deal with sqlite3StackAlloc() failures to be unreachable.
3088 */
3089 #ifdef SQLITE_USE_ALLOCA
3090 # define sqlite3StackAllocRaw(D,N)   alloca(N)
3091 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
3092 # define sqlite3StackFree(D,P)
3093 #else
3094 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
3095 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
3096 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
3097 #endif
3098 
3099 #ifdef SQLITE_ENABLE_MEMSYS3
3100 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
3101 #endif
3102 #ifdef SQLITE_ENABLE_MEMSYS5
3103 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
3104 #endif
3105 
3106 
3107 #ifndef SQLITE_MUTEX_OMIT
3108   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
3109   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
3110   sqlite3_mutex *sqlite3MutexAlloc(int);
3111   int sqlite3MutexInit(void);
3112   int sqlite3MutexEnd(void);
3113 #endif
3114 
3115 sqlite3_int64 sqlite3StatusValue(int);
3116 void sqlite3StatusUp(int, int);
3117 void sqlite3StatusDown(int, int);
3118 void sqlite3StatusSet(int, int);
3119 
3120 /* Access to mutexes used by sqlite3_status() */
3121 sqlite3_mutex *sqlite3Pcache1Mutex(void);
3122 sqlite3_mutex *sqlite3MallocMutex(void);
3123 
3124 #ifndef SQLITE_OMIT_FLOATING_POINT
3125   int sqlite3IsNaN(double);
3126 #else
3127 # define sqlite3IsNaN(X)  0
3128 #endif
3129 
3130 /*
3131 ** An instance of the following structure holds information about SQL
3132 ** functions arguments that are the parameters to the printf() function.
3133 */
3134 struct PrintfArguments {
3135   int nArg;                /* Total number of arguments */
3136   int nUsed;               /* Number of arguments used so far */
3137   sqlite3_value **apArg;   /* The argument values */
3138 };
3139 
3140 #define SQLITE_PRINTF_INTERNAL 0x01
3141 #define SQLITE_PRINTF_SQLFUNC  0x02
3142 void sqlite3VXPrintf(StrAccum*, u32, const char*, va_list);
3143 void sqlite3XPrintf(StrAccum*, u32, const char*, ...);
3144 char *sqlite3MPrintf(sqlite3*,const char*, ...);
3145 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
3146 char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
3147 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
3148   void sqlite3DebugPrintf(const char*, ...);
3149 #endif
3150 #if defined(SQLITE_TEST)
3151   void *sqlite3TestTextToPtr(const char*);
3152 #endif
3153 
3154 #if defined(SQLITE_DEBUG)
3155   TreeView *sqlite3TreeViewPush(TreeView*,u8);
3156   void sqlite3TreeViewPop(TreeView*);
3157   void sqlite3TreeViewLine(TreeView*, const char*, ...);
3158   void sqlite3TreeViewItem(TreeView*, const char*, u8);
3159   void sqlite3TreeViewExpr(TreeView*, const Expr*, u8);
3160   void sqlite3TreeViewExprList(TreeView*, const ExprList*, u8, const char*);
3161   void sqlite3TreeViewSelect(TreeView*, const Select*, u8);
3162 #endif
3163 
3164 
3165 void sqlite3SetString(char **, sqlite3*, const char*, ...);
3166 void sqlite3ErrorMsg(Parse*, const char*, ...);
3167 int sqlite3Dequote(char*);
3168 int sqlite3KeywordCode(const unsigned char*, int);
3169 int sqlite3RunParser(Parse*, const char*, char **);
3170 void sqlite3FinishCoding(Parse*);
3171 int sqlite3GetTempReg(Parse*);
3172 void sqlite3ReleaseTempReg(Parse*,int);
3173 int sqlite3GetTempRange(Parse*,int);
3174 void sqlite3ReleaseTempRange(Parse*,int,int);
3175 void sqlite3ClearTempRegCache(Parse*);
3176 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
3177 Expr *sqlite3Expr(sqlite3*,int,const char*);
3178 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
3179 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
3180 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
3181 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
3182 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
3183 void sqlite3ExprDelete(sqlite3*, Expr*);
3184 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
3185 void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
3186 void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
3187 void sqlite3ExprListDelete(sqlite3*, ExprList*);
3188 u32 sqlite3ExprListFlags(const ExprList*);
3189 int sqlite3Init(sqlite3*, char**);
3190 int sqlite3InitCallback(void*, int, char**, char**);
3191 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
3192 void sqlite3ResetAllSchemasOfConnection(sqlite3*);
3193 void sqlite3ResetOneSchema(sqlite3*,int);
3194 void sqlite3CollapseDatabaseArray(sqlite3*);
3195 void sqlite3BeginParse(Parse*,int);
3196 void sqlite3CommitInternalChanges(sqlite3*);
3197 Table *sqlite3ResultSetOfSelect(Parse*,Select*);
3198 void sqlite3OpenMasterTable(Parse *, int);
3199 Index *sqlite3PrimaryKeyIndex(Table*);
3200 i16 sqlite3ColumnOfIndex(Index*, i16);
3201 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
3202 void sqlite3AddColumn(Parse*,Token*);
3203 void sqlite3AddNotNull(Parse*, int);
3204 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
3205 void sqlite3AddCheckConstraint(Parse*, Expr*);
3206 void sqlite3AddColumnType(Parse*,Token*);
3207 void sqlite3AddDefaultValue(Parse*,ExprSpan*);
3208 void sqlite3AddCollateType(Parse*, Token*);
3209 void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
3210 int sqlite3ParseUri(const char*,const char*,unsigned int*,
3211                     sqlite3_vfs**,char**,char **);
3212 Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
3213 int sqlite3CodeOnce(Parse *);
3214 
3215 #ifdef SQLITE_OMIT_BUILTIN_TEST
3216 # define sqlite3FaultSim(X) SQLITE_OK
3217 #else
3218   int sqlite3FaultSim(int);
3219 #endif
3220 
3221 Bitvec *sqlite3BitvecCreate(u32);
3222 int sqlite3BitvecTest(Bitvec*, u32);
3223 int sqlite3BitvecSet(Bitvec*, u32);
3224 void sqlite3BitvecClear(Bitvec*, u32, void*);
3225 void sqlite3BitvecDestroy(Bitvec*);
3226 u32 sqlite3BitvecSize(Bitvec*);
3227 int sqlite3BitvecBuiltinTest(int,int*);
3228 
3229 RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
3230 void sqlite3RowSetClear(RowSet*);
3231 void sqlite3RowSetInsert(RowSet*, i64);
3232 int sqlite3RowSetTest(RowSet*, int iBatch, i64);
3233 int sqlite3RowSetNext(RowSet*, i64*);
3234 
3235 void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
3236 
3237 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
3238   int sqlite3ViewGetColumnNames(Parse*,Table*);
3239 #else
3240 # define sqlite3ViewGetColumnNames(A,B) 0
3241 #endif
3242 
3243 #if SQLITE_MAX_ATTACHED>30
3244   int sqlite3DbMaskAllZero(yDbMask);
3245 #endif
3246 void sqlite3DropTable(Parse*, SrcList*, int, int);
3247 void sqlite3CodeDropTable(Parse*, Table*, int, int);
3248 void sqlite3DeleteTable(sqlite3*, Table*);
3249 #ifndef SQLITE_OMIT_AUTOINCREMENT
3250   void sqlite3AutoincrementBegin(Parse *pParse);
3251   void sqlite3AutoincrementEnd(Parse *pParse);
3252 #else
3253 # define sqlite3AutoincrementBegin(X)
3254 # define sqlite3AutoincrementEnd(X)
3255 #endif
3256 void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int);
3257 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
3258 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
3259 int sqlite3IdListIndex(IdList*,const char*);
3260 SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
3261 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
3262 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
3263                                       Token*, Select*, Expr*, IdList*);
3264 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
3265 int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
3266 void sqlite3SrcListShiftJoinType(SrcList*);
3267 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
3268 void sqlite3IdListDelete(sqlite3*, IdList*);
3269 void sqlite3SrcListDelete(sqlite3*, SrcList*);
3270 Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
3271 Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
3272                           Expr*, int, int);
3273 void sqlite3DropIndex(Parse*, SrcList*, int);
3274 int sqlite3Select(Parse*, Select*, SelectDest*);
3275 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
3276                          Expr*,ExprList*,u16,Expr*,Expr*);
3277 void sqlite3SelectDelete(sqlite3*, Select*);
3278 Table *sqlite3SrcListLookup(Parse*, SrcList*);
3279 int sqlite3IsReadOnly(Parse*, Table*, int);
3280 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
3281 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
3282 Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,Expr*,char*);
3283 #endif
3284 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
3285 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
3286 WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
3287 void sqlite3WhereEnd(WhereInfo*);
3288 u64 sqlite3WhereOutputRowCount(WhereInfo*);
3289 int sqlite3WhereIsDistinct(WhereInfo*);
3290 int sqlite3WhereIsOrdered(WhereInfo*);
3291 int sqlite3WhereIsSorted(WhereInfo*);
3292 int sqlite3WhereContinueLabel(WhereInfo*);
3293 int sqlite3WhereBreakLabel(WhereInfo*);
3294 int sqlite3WhereOkOnePass(WhereInfo*, int*);
3295 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
3296 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
3297 void sqlite3ExprCodeMove(Parse*, int, int, int);
3298 void sqlite3ExprCacheStore(Parse*, int, int, int);
3299 void sqlite3ExprCachePush(Parse*);
3300 void sqlite3ExprCachePop(Parse*);
3301 void sqlite3ExprCacheRemove(Parse*, int, int);
3302 void sqlite3ExprCacheClear(Parse*);
3303 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
3304 void sqlite3ExprCode(Parse*, Expr*, int);
3305 void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
3306 void sqlite3ExprCodeAtInit(Parse*, Expr*, int, u8);
3307 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
3308 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
3309 void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
3310 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, u8);
3311 #define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
3312 #define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
3313 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
3314 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
3315 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
3316 Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
3317 Table *sqlite3LocateTableItem(Parse*,int isView,struct SrcList_item *);
3318 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
3319 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
3320 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
3321 void sqlite3Vacuum(Parse*);
3322 int sqlite3RunVacuum(char**, sqlite3*);
3323 char *sqlite3NameFromToken(sqlite3*, Token*);
3324 int sqlite3ExprCompare(Expr*, Expr*, int);
3325 int sqlite3ExprListCompare(ExprList*, ExprList*, int);
3326 int sqlite3ExprImpliesExpr(Expr*, Expr*, int);
3327 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
3328 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
3329 int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
3330 Vdbe *sqlite3GetVdbe(Parse*);
3331 void sqlite3PrngSaveState(void);
3332 void sqlite3PrngRestoreState(void);
3333 void sqlite3RollbackAll(sqlite3*,int);
3334 void sqlite3CodeVerifySchema(Parse*, int);
3335 void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
3336 void sqlite3BeginTransaction(Parse*, int);
3337 void sqlite3CommitTransaction(Parse*);
3338 void sqlite3RollbackTransaction(Parse*);
3339 void sqlite3Savepoint(Parse*, int, Token*);
3340 void sqlite3CloseSavepoints(sqlite3 *);
3341 void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
3342 int sqlite3ExprIsConstant(Expr*);
3343 int sqlite3ExprIsConstantNotJoin(Expr*);
3344 int sqlite3ExprIsConstantOrFunction(Expr*, u8);
3345 int sqlite3ExprIsTableConstant(Expr*,int);
3346 int sqlite3ExprIsInteger(Expr*, int*);
3347 int sqlite3ExprCanBeNull(const Expr*);
3348 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
3349 int sqlite3IsRowid(const char*);
3350 void sqlite3GenerateRowDelete(Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8);
3351 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*);
3352 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
3353 void sqlite3ResolvePartIdxLabel(Parse*,int);
3354 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
3355                                      u8,u8,int,int*);
3356 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
3357 int sqlite3OpenTableAndIndices(Parse*, Table*, int, int, u8*, int*, int*);
3358 void sqlite3BeginWriteOperation(Parse*, int, int);
3359 void sqlite3MultiWrite(Parse*);
3360 void sqlite3MayAbort(Parse*);
3361 void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
3362 void sqlite3UniqueConstraint(Parse*, int, Index*);
3363 void sqlite3RowidConstraint(Parse*, int, Table*);
3364 Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
3365 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
3366 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
3367 IdList *sqlite3IdListDup(sqlite3*,IdList*);
3368 Select *sqlite3SelectDup(sqlite3*,Select*,int);
3369 #if SELECTTRACE_ENABLED
3370 void sqlite3SelectSetName(Select*,const char*);
3371 #else
3372 # define sqlite3SelectSetName(A,B)
3373 #endif
3374 void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
3375 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
3376 void sqlite3RegisterBuiltinFunctions(sqlite3*);
3377 void sqlite3RegisterDateTimeFunctions(void);
3378 void sqlite3RegisterGlobalFunctions(void);
3379 int sqlite3SafetyCheckOk(sqlite3*);
3380 int sqlite3SafetyCheckSickOrOk(sqlite3*);
3381 void sqlite3ChangeCookie(Parse*, int);
3382 
3383 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
3384 void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
3385 #endif
3386 
3387 #ifndef SQLITE_OMIT_TRIGGER
3388   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
3389                            Expr*,int, int);
3390   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
3391   void sqlite3DropTrigger(Parse*, SrcList*, int);
3392   void sqlite3DropTriggerPtr(Parse*, Trigger*);
3393   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
3394   Trigger *sqlite3TriggerList(Parse *, Table *);
3395   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
3396                             int, int, int);
3397   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
3398   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
3399   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
3400   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
3401   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
3402                                         Select*,u8);
3403   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
3404   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
3405   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
3406   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
3407   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
3408 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
3409 #else
3410 # define sqlite3TriggersExist(B,C,D,E,F) 0
3411 # define sqlite3DeleteTrigger(A,B)
3412 # define sqlite3DropTriggerPtr(A,B)
3413 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
3414 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
3415 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
3416 # define sqlite3TriggerList(X, Y) 0
3417 # define sqlite3ParseToplevel(p) p
3418 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
3419 #endif
3420 
3421 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
3422 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
3423 void sqlite3DeferForeignKey(Parse*, int);
3424 #ifndef SQLITE_OMIT_AUTHORIZATION
3425   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
3426   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
3427   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
3428   void sqlite3AuthContextPop(AuthContext*);
3429   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
3430 #else
3431 # define sqlite3AuthRead(a,b,c,d)
3432 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
3433 # define sqlite3AuthContextPush(a,b,c)
3434 # define sqlite3AuthContextPop(a)  ((void)(a))
3435 #endif
3436 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
3437 void sqlite3Detach(Parse*, Expr*);
3438 void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
3439 int sqlite3FixSrcList(DbFixer*, SrcList*);
3440 int sqlite3FixSelect(DbFixer*, Select*);
3441 int sqlite3FixExpr(DbFixer*, Expr*);
3442 int sqlite3FixExprList(DbFixer*, ExprList*);
3443 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
3444 int sqlite3AtoF(const char *z, double*, int, u8);
3445 int sqlite3GetInt32(const char *, int*);
3446 int sqlite3Atoi(const char*);
3447 int sqlite3Utf16ByteLen(const void *pData, int nChar);
3448 int sqlite3Utf8CharLen(const char *pData, int nByte);
3449 u32 sqlite3Utf8Read(const u8**);
3450 LogEst sqlite3LogEst(u64);
3451 LogEst sqlite3LogEstAdd(LogEst,LogEst);
3452 #ifndef SQLITE_OMIT_VIRTUALTABLE
3453 LogEst sqlite3LogEstFromDouble(double);
3454 #endif
3455 u64 sqlite3LogEstToInt(LogEst);
3456 
3457 /*
3458 ** Routines to read and write variable-length integers.  These used to
3459 ** be defined locally, but now we use the varint routines in the util.c
3460 ** file.
3461 */
3462 int sqlite3PutVarint(unsigned char*, u64);
3463 u8 sqlite3GetVarint(const unsigned char *, u64 *);
3464 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
3465 int sqlite3VarintLen(u64 v);
3466 
3467 /*
3468 ** The common case is for a varint to be a single byte.  They following
3469 ** macros handle the common case without a procedure call, but then call
3470 ** the procedure for larger varints.
3471 */
3472 #define getVarint32(A,B)  \
3473   (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
3474 #define putVarint32(A,B)  \
3475   (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
3476   sqlite3PutVarint((A),(B)))
3477 #define getVarint    sqlite3GetVarint
3478 #define putVarint    sqlite3PutVarint
3479 
3480 
3481 const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
3482 void sqlite3TableAffinity(Vdbe*, Table*, int);
3483 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
3484 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
3485 char sqlite3ExprAffinity(Expr *pExpr);
3486 int sqlite3Atoi64(const char*, i64*, int, u8);
3487 int sqlite3DecOrHexToI64(const char*, i64*);
3488 void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
3489 void sqlite3Error(sqlite3*,int);
3490 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
3491 u8 sqlite3HexToInt(int h);
3492 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
3493 
3494 #if defined(SQLITE_DEBUG) && \
3495     (defined(SQLITE_TEST) || defined(SQLITE_FORCE_OS_TRACE))
3496 const char *sqlite3ErrName(int);
3497 #endif
3498 
3499 const char *sqlite3ErrStr(int);
3500 int sqlite3ReadSchema(Parse *pParse);
3501 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
3502 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
3503 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
3504 Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*, int);
3505 Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
3506 Expr *sqlite3ExprSkipCollate(Expr*);
3507 int sqlite3CheckCollSeq(Parse *, CollSeq *);
3508 int sqlite3CheckObjectName(Parse *, const char *);
3509 void sqlite3VdbeSetChanges(sqlite3 *, int);
3510 int sqlite3AddInt64(i64*,i64);
3511 int sqlite3SubInt64(i64*,i64);
3512 int sqlite3MulInt64(i64*,i64);
3513 int sqlite3AbsInt32(int);
3514 #ifdef SQLITE_ENABLE_8_3_NAMES
3515 void sqlite3FileSuffix3(const char*, char*);
3516 #else
3517 # define sqlite3FileSuffix3(X,Y)
3518 #endif
3519 u8 sqlite3GetBoolean(const char *z,u8);
3520 
3521 const void *sqlite3ValueText(sqlite3_value*, u8);
3522 int sqlite3ValueBytes(sqlite3_value*, u8);
3523 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
3524                         void(*)(void*));
3525 void sqlite3ValueSetNull(sqlite3_value*);
3526 void sqlite3ValueFree(sqlite3_value*);
3527 sqlite3_value *sqlite3ValueNew(sqlite3 *);
3528 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
3529 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
3530 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
3531 #ifndef SQLITE_AMALGAMATION
3532 extern const unsigned char sqlite3OpcodeProperty[];
3533 extern const unsigned char sqlite3UpperToLower[];
3534 extern const unsigned char sqlite3CtypeMap[];
3535 extern const Token sqlite3IntTokens[];
3536 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
3537 extern SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
3538 #ifndef SQLITE_OMIT_WSD
3539 extern int sqlite3PendingByte;
3540 #endif
3541 #endif
3542 void sqlite3RootPageMoved(sqlite3*, int, int, int);
3543 void sqlite3Reindex(Parse*, Token*, Token*);
3544 void sqlite3AlterFunctions(void);
3545 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
3546 int sqlite3GetToken(const unsigned char *, int *);
3547 void sqlite3NestedParse(Parse*, const char*, ...);
3548 void sqlite3ExpirePreparedStatements(sqlite3*);
3549 int sqlite3CodeSubselect(Parse *, Expr *, int, int);
3550 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
3551 int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
3552 int sqlite3ResolveExprNames(NameContext*, Expr*);
3553 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
3554 void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
3555 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
3556 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
3557 void sqlite3AlterFinishAddColumn(Parse *, Token *);
3558 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
3559 CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
3560 char sqlite3AffinityType(const char*, u8*);
3561 void sqlite3Analyze(Parse*, Token*, Token*);
3562 int sqlite3InvokeBusyHandler(BusyHandler*);
3563 int sqlite3FindDb(sqlite3*, Token*);
3564 int sqlite3FindDbName(sqlite3 *, const char *);
3565 int sqlite3AnalysisLoad(sqlite3*,int iDB);
3566 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
3567 void sqlite3DefaultRowEst(Index*);
3568 void sqlite3RegisterLikeFunctions(sqlite3*, int);
3569 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
3570 void sqlite3MinimumFileFormat(Parse*, int, int);
3571 void sqlite3SchemaClear(void *);
3572 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
3573 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
3574 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
3575 void sqlite3KeyInfoUnref(KeyInfo*);
3576 KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
3577 KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
3578 #ifdef SQLITE_DEBUG
3579 int sqlite3KeyInfoIsWriteable(KeyInfo*);
3580 #endif
3581 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
3582   void (*)(sqlite3_context*,int,sqlite3_value **),
3583   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
3584   FuncDestructor *pDestructor
3585 );
3586 int sqlite3ApiExit(sqlite3 *db, int);
3587 int sqlite3OpenTempDatabase(Parse *);
3588 
3589 void sqlite3StrAccumInit(StrAccum*, char*, int, int);
3590 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
3591 void sqlite3StrAccumAppendAll(StrAccum*,const char*);
3592 void sqlite3AppendChar(StrAccum*,int,char);
3593 char *sqlite3StrAccumFinish(StrAccum*);
3594 void sqlite3StrAccumReset(StrAccum*);
3595 void sqlite3SelectDestInit(SelectDest*,int,int);
3596 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
3597 
3598 void sqlite3BackupRestart(sqlite3_backup *);
3599 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
3600 
3601 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
3602 void sqlite3AnalyzeFunctions(void);
3603 int sqlite3Stat4ProbeSetValue(Parse*,Index*,UnpackedRecord**,Expr*,u8,int,int*);
3604 int sqlite3Stat4ValueFromExpr(Parse*, Expr*, u8, sqlite3_value**);
3605 void sqlite3Stat4ProbeFree(UnpackedRecord*);
3606 int sqlite3Stat4Column(sqlite3*, const void*, int, int, sqlite3_value**);
3607 #endif
3608 
3609 /*
3610 ** The interface to the LEMON-generated parser
3611 */
3612 void *sqlite3ParserAlloc(void*(*)(u64));
3613 void sqlite3ParserFree(void*, void(*)(void*));
3614 void sqlite3Parser(void*, int, Token, Parse*);
3615 #ifdef YYTRACKMAXSTACKDEPTH
3616   int sqlite3ParserStackPeak(void*);
3617 #endif
3618 
3619 void sqlite3AutoLoadExtensions(sqlite3*);
3620 #ifndef SQLITE_OMIT_LOAD_EXTENSION
3621   void sqlite3CloseExtensions(sqlite3*);
3622 #else
3623 # define sqlite3CloseExtensions(X)
3624 #endif
3625 
3626 #ifndef SQLITE_OMIT_SHARED_CACHE
3627   void sqlite3TableLock(Parse *, int, int, u8, const char *);
3628 #else
3629   #define sqlite3TableLock(v,w,x,y,z)
3630 #endif
3631 
3632 #ifdef SQLITE_TEST
3633   int sqlite3Utf8To8(unsigned char*);
3634 #endif
3635 
3636 #ifdef SQLITE_OMIT_VIRTUALTABLE
3637 #  define sqlite3VtabClear(Y)
3638 #  define sqlite3VtabSync(X,Y) SQLITE_OK
3639 #  define sqlite3VtabRollback(X)
3640 #  define sqlite3VtabCommit(X)
3641 #  define sqlite3VtabInSync(db) 0
3642 #  define sqlite3VtabLock(X)
3643 #  define sqlite3VtabUnlock(X)
3644 #  define sqlite3VtabUnlockList(X)
3645 #  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
3646 #  define sqlite3GetVTable(X,Y)  ((VTable*)0)
3647 #else
3648    void sqlite3VtabClear(sqlite3 *db, Table*);
3649    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
3650    int sqlite3VtabSync(sqlite3 *db, Vdbe*);
3651    int sqlite3VtabRollback(sqlite3 *db);
3652    int sqlite3VtabCommit(sqlite3 *db);
3653    void sqlite3VtabLock(VTable *);
3654    void sqlite3VtabUnlock(VTable *);
3655    void sqlite3VtabUnlockList(sqlite3*);
3656    int sqlite3VtabSavepoint(sqlite3 *, int, int);
3657    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
3658    VTable *sqlite3GetVTable(sqlite3*, Table*);
3659 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
3660 #endif
3661 void sqlite3VtabMakeWritable(Parse*,Table*);
3662 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
3663 void sqlite3VtabFinishParse(Parse*, Token*);
3664 void sqlite3VtabArgInit(Parse*);
3665 void sqlite3VtabArgExtend(Parse*, Token*);
3666 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
3667 int sqlite3VtabCallConnect(Parse*, Table*);
3668 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
3669 int sqlite3VtabBegin(sqlite3 *, VTable *);
3670 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
3671 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
3672 sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
3673 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
3674 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
3675 void sqlite3ParserReset(Parse*);
3676 int sqlite3Reprepare(Vdbe*);
3677 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
3678 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
3679 int sqlite3TempInMemory(const sqlite3*);
3680 const char *sqlite3JournalModename(int);
3681 #ifndef SQLITE_OMIT_WAL
3682   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
3683   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
3684 #endif
3685 #ifndef SQLITE_OMIT_CTE
3686   With *sqlite3WithAdd(Parse*,With*,Token*,ExprList*,Select*);
3687   void sqlite3WithDelete(sqlite3*,With*);
3688   void sqlite3WithPush(Parse*, With*, u8);
3689 #else
3690 #define sqlite3WithPush(x,y,z)
3691 #define sqlite3WithDelete(x,y)
3692 #endif
3693 
3694 /* Declarations for functions in fkey.c. All of these are replaced by
3695 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
3696 ** key functionality is available. If OMIT_TRIGGER is defined but
3697 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
3698 ** this case foreign keys are parsed, but no other functionality is
3699 ** provided (enforcement of FK constraints requires the triggers sub-system).
3700 */
3701 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
3702   void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
3703   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
3704   void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
3705   int sqlite3FkRequired(Parse*, Table*, int*, int);
3706   u32 sqlite3FkOldmask(Parse*, Table*);
3707   FKey *sqlite3FkReferences(Table *);
3708 #else
3709   #define sqlite3FkActions(a,b,c,d,e,f)
3710   #define sqlite3FkCheck(a,b,c,d,e,f)
3711   #define sqlite3FkDropTable(a,b,c)
3712   #define sqlite3FkOldmask(a,b)         0
3713   #define sqlite3FkRequired(a,b,c,d)    0
3714 #endif
3715 #ifndef SQLITE_OMIT_FOREIGN_KEY
3716   void sqlite3FkDelete(sqlite3 *, Table*);
3717   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
3718 #else
3719   #define sqlite3FkDelete(a,b)
3720   #define sqlite3FkLocateIndex(a,b,c,d,e)
3721 #endif
3722 
3723 
3724 /*
3725 ** Available fault injectors.  Should be numbered beginning with 0.
3726 */
3727 #define SQLITE_FAULTINJECTOR_MALLOC     0
3728 #define SQLITE_FAULTINJECTOR_COUNT      1
3729 
3730 /*
3731 ** The interface to the code in fault.c used for identifying "benign"
3732 ** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
3733 ** is not defined.
3734 */
3735 #ifndef SQLITE_OMIT_BUILTIN_TEST
3736   void sqlite3BeginBenignMalloc(void);
3737   void sqlite3EndBenignMalloc(void);
3738 #else
3739   #define sqlite3BeginBenignMalloc()
3740   #define sqlite3EndBenignMalloc()
3741 #endif
3742 
3743 /*
3744 ** Allowed return values from sqlite3FindInIndex()
3745 */
3746 #define IN_INDEX_ROWID        1   /* Search the rowid of the table */
3747 #define IN_INDEX_EPH          2   /* Search an ephemeral b-tree */
3748 #define IN_INDEX_INDEX_ASC    3   /* Existing index ASCENDING */
3749 #define IN_INDEX_INDEX_DESC   4   /* Existing index DESCENDING */
3750 #define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
3751 /*
3752 ** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
3753 */
3754 #define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
3755 #define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
3756 #define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
3757 int sqlite3FindInIndex(Parse *, Expr *, u32, int*);
3758 
3759 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
3760   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
3761   int sqlite3JournalSize(sqlite3_vfs *);
3762   int sqlite3JournalCreate(sqlite3_file *);
3763   int sqlite3JournalExists(sqlite3_file *p);
3764 #else
3765   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
3766   #define sqlite3JournalExists(p) 1
3767 #endif
3768 
3769 void sqlite3MemJournalOpen(sqlite3_file *);
3770 int sqlite3MemJournalSize(void);
3771 int sqlite3IsMemJournal(sqlite3_file *);
3772 
3773 void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p);
3774 #if SQLITE_MAX_EXPR_DEPTH>0
3775   int sqlite3SelectExprHeight(Select *);
3776   int sqlite3ExprCheckHeight(Parse*, int);
3777 #else
3778   #define sqlite3SelectExprHeight(x) 0
3779   #define sqlite3ExprCheckHeight(x,y)
3780 #endif
3781 
3782 u32 sqlite3Get4byte(const u8*);
3783 void sqlite3Put4byte(u8*, u32);
3784 
3785 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
3786   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
3787   void sqlite3ConnectionUnlocked(sqlite3 *db);
3788   void sqlite3ConnectionClosed(sqlite3 *db);
3789 #else
3790   #define sqlite3ConnectionBlocked(x,y)
3791   #define sqlite3ConnectionUnlocked(x)
3792   #define sqlite3ConnectionClosed(x)
3793 #endif
3794 
3795 #ifdef SQLITE_DEBUG
3796   void sqlite3ParserTrace(FILE*, char *);
3797 #endif
3798 
3799 /*
3800 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
3801 ** sqlite3IoTrace is a pointer to a printf-like routine used to
3802 ** print I/O tracing messages.
3803 */
3804 #ifdef SQLITE_ENABLE_IOTRACE
3805 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
3806   void sqlite3VdbeIOTraceSql(Vdbe*);
3807 SQLITE_API SQLITE_EXTERN void (SQLITE_CDECL *sqlite3IoTrace)(const char*,...);
3808 #else
3809 # define IOTRACE(A)
3810 # define sqlite3VdbeIOTraceSql(X)
3811 #endif
3812 
3813 /*
3814 ** These routines are available for the mem2.c debugging memory allocator
3815 ** only.  They are used to verify that different "types" of memory
3816 ** allocations are properly tracked by the system.
3817 **
3818 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
3819 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
3820 ** a single bit set.
3821 **
3822 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
3823 ** argument match the type set by the previous sqlite3MemdebugSetType().
3824 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
3825 **
3826 ** sqlite3MemdebugNoType() returns true if none of the bits in its second
3827 ** argument match the type set by the previous sqlite3MemdebugSetType().
3828 **
3829 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
3830 ** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
3831 ** it might have been allocated by lookaside, except the allocation was
3832 ** too large or lookaside was already full.  It is important to verify
3833 ** that allocations that might have been satisfied by lookaside are not
3834 ** passed back to non-lookaside free() routines.  Asserts such as the
3835 ** example above are placed on the non-lookaside free() routines to verify
3836 ** this constraint.
3837 **
3838 ** All of this is no-op for a production build.  It only comes into
3839 ** play when the SQLITE_MEMDEBUG compile-time option is used.
3840 */
3841 #ifdef SQLITE_MEMDEBUG
3842   void sqlite3MemdebugSetType(void*,u8);
3843   int sqlite3MemdebugHasType(void*,u8);
3844   int sqlite3MemdebugNoType(void*,u8);
3845 #else
3846 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
3847 # define sqlite3MemdebugHasType(X,Y)  1
3848 # define sqlite3MemdebugNoType(X,Y)   1
3849 #endif
3850 #define MEMTYPE_HEAP       0x01  /* General heap allocations */
3851 #define MEMTYPE_LOOKASIDE  0x02  /* Heap that might have been lookaside */
3852 #define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
3853 #define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
3854 
3855 /*
3856 ** Threading interface
3857 */
3858 #if SQLITE_MAX_WORKER_THREADS>0
3859 int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
3860 int sqlite3ThreadJoin(SQLiteThread*, void**);
3861 #endif
3862 
3863 #endif /* _SQLITEINT_H_ */
3864