xref: /sqlite-3.40.0/src/sqliteInt.h (revision 6117272e)
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 ** These #defines should enable >2GB file support on POSIX if the
20 ** underlying operating system supports it.  If the OS lacks
21 ** large file support, or if the OS is windows, these should be no-ops.
22 **
23 ** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
24 ** system #includes.  Hence, this block of code must be the very first
25 ** code in all source files.
26 **
27 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
28 ** on the compiler command line.  This is necessary if you are compiling
29 ** on a recent machine (ex: Red Hat 7.2) but you want your code to work
30 ** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
31 ** without this option, LFS is enable.  But LFS does not exist in the kernel
32 ** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
33 ** portability you should omit LFS.
34 **
35 ** The previous paragraph was written in 2005.  (This paragraph is written
36 ** on 2008-11-28.) These days, all Linux kernels support large files, so
37 ** you should probably leave LFS enabled.  But some embedded platforms might
38 ** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
39 **
40 ** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
41 */
42 #ifndef SQLITE_DISABLE_LFS
43 # define _LARGE_FILE       1
44 # ifndef _FILE_OFFSET_BITS
45 #   define _FILE_OFFSET_BITS 64
46 # endif
47 # define _LARGEFILE_SOURCE 1
48 #endif
49 
50 /*
51 ** For MinGW, check to see if we can include the header file containing its
52 ** version information, among other things.  Normally, this internal MinGW
53 ** header file would [only] be included automatically by other MinGW header
54 ** files; however, the contained version information is now required by this
55 ** header file to work around binary compatibility issues (see below) and
56 ** this is the only known way to reliably obtain it.  This entire #if block
57 ** would be completely unnecessary if there was any other way of detecting
58 ** MinGW via their preprocessor (e.g. if they customized their GCC to define
59 ** some MinGW-specific macros).  When compiling for MinGW, either the
60 ** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
61 ** defined; otherwise, detection of conditions specific to MinGW will be
62 ** disabled.
63 */
64 #if defined(_HAVE_MINGW_H)
65 # include "mingw.h"
66 #elif defined(_HAVE__MINGW_H)
67 # include "_mingw.h"
68 #endif
69 
70 /*
71 ** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
72 ** define is required to maintain binary compatibility with the MSVC runtime
73 ** library in use (e.g. for Windows XP).
74 */
75 #if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
76     defined(_WIN32) && !defined(_WIN64) && \
77     defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
78     defined(__MSVCRT__)
79 # define _USE_32BIT_TIME_T
80 #endif
81 
82 /* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
83 ** first in QNX.  Also, the _USE_32BIT_TIME_T macro must appear first for
84 ** MinGW.
85 */
86 #include "sqlite3.h"
87 
88 /*
89 ** Include the configuration header output by 'configure' if we're using the
90 ** autoconf-based build
91 */
92 #ifdef _HAVE_SQLITE_CONFIG_H
93 #include "config.h"
94 #endif
95 
96 #include "sqliteLimit.h"
97 
98 /* Disable nuisance warnings on Borland compilers */
99 #if defined(__BORLANDC__)
100 #pragma warn -rch /* unreachable code */
101 #pragma warn -ccc /* Condition is always true or false */
102 #pragma warn -aus /* Assigned value is never used */
103 #pragma warn -csu /* Comparing signed and unsigned */
104 #pragma warn -spa /* Suspicious pointer arithmetic */
105 #endif
106 
107 /* Needed for various definitions... */
108 #ifndef _GNU_SOURCE
109 # define _GNU_SOURCE
110 #endif
111 
112 #if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
113 # define _BSD_SOURCE
114 #endif
115 
116 /*
117 ** Include standard header files as necessary
118 */
119 #ifdef HAVE_STDINT_H
120 #include <stdint.h>
121 #endif
122 #ifdef HAVE_INTTYPES_H
123 #include <inttypes.h>
124 #endif
125 
126 /*
127 ** The following macros are used to cast pointers to integers and
128 ** integers to pointers.  The way you do this varies from one compiler
129 ** to the next, so we have developed the following set of #if statements
130 ** to generate appropriate macros for a wide range of compilers.
131 **
132 ** The correct "ANSI" way to do this is to use the intptr_t type.
133 ** Unfortunately, that typedef is not available on all compilers, or
134 ** if it is available, it requires an #include of specific headers
135 ** that vary from one machine to the next.
136 **
137 ** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
138 ** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
139 ** So we have to define the macros in different ways depending on the
140 ** compiler.
141 */
142 #if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
143 # define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
144 # define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
145 #elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
146 # define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
147 # define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
148 #elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
149 # define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
150 # define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
151 #else                          /* Generates a warning - but it always works */
152 # define SQLITE_INT_TO_PTR(X)  ((void*)(X))
153 # define SQLITE_PTR_TO_INT(X)  ((int)(X))
154 #endif
155 
156 /*
157 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
158 ** 0 means mutexes are permanently disable and the library is never
159 ** threadsafe.  1 means the library is serialized which is the highest
160 ** level of threadsafety.  2 means the library is multithreaded - multiple
161 ** threads can use SQLite as long as no two threads try to use the same
162 ** database connection at the same time.
163 **
164 ** Older versions of SQLite used an optional THREADSAFE macro.
165 ** We support that for legacy.
166 */
167 #if !defined(SQLITE_THREADSAFE)
168 # if defined(THREADSAFE)
169 #   define SQLITE_THREADSAFE THREADSAFE
170 # else
171 #   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
172 # endif
173 #endif
174 
175 /*
176 ** Powersafe overwrite is on by default.  But can be turned off using
177 ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
178 */
179 #ifndef SQLITE_POWERSAFE_OVERWRITE
180 # define SQLITE_POWERSAFE_OVERWRITE 1
181 #endif
182 
183 /*
184 ** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
185 ** It determines whether or not the features related to
186 ** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
187 ** be overridden at runtime using the sqlite3_config() API.
188 */
189 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
190 # define SQLITE_DEFAULT_MEMSTATUS 1
191 #endif
192 
193 /*
194 ** Exactly one of the following macros must be defined in order to
195 ** specify which memory allocation subsystem to use.
196 **
197 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
198 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
199 **     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
200 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
201 **
202 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
203 ** assert() macro is enabled, each call into the Win32 native heap subsystem
204 ** will cause HeapValidate to be called.  If heap validation should fail, an
205 ** assertion will be triggered.
206 **
207 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
208 ** the default.
209 */
210 #if defined(SQLITE_SYSTEM_MALLOC) \
211   + defined(SQLITE_WIN32_MALLOC) \
212   + defined(SQLITE_ZERO_MALLOC) \
213   + defined(SQLITE_MEMDEBUG)>1
214 # error "Two or more of the following compile-time configuration options\
215  are defined but at most one is allowed:\
216  SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
217  SQLITE_ZERO_MALLOC"
218 #endif
219 #if defined(SQLITE_SYSTEM_MALLOC) \
220   + defined(SQLITE_WIN32_MALLOC) \
221   + defined(SQLITE_ZERO_MALLOC) \
222   + defined(SQLITE_MEMDEBUG)==0
223 # define SQLITE_SYSTEM_MALLOC 1
224 #endif
225 
226 /*
227 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
228 ** sizes of memory allocations below this value where possible.
229 */
230 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
231 # define SQLITE_MALLOC_SOFT_LIMIT 1024
232 #endif
233 
234 /*
235 ** We need to define _XOPEN_SOURCE as follows in order to enable
236 ** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
237 ** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
238 ** it.
239 */
240 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
241 #  define _XOPEN_SOURCE 600
242 #endif
243 
244 /*
245 ** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
246 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
247 ** make it true by defining or undefining NDEBUG.
248 **
249 ** Setting NDEBUG makes the code smaller and faster by disabling the
250 ** assert() statements in the code.  So we want the default action
251 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
252 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
253 ** feature.
254 */
255 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
256 # define NDEBUG 1
257 #endif
258 #if defined(NDEBUG) && defined(SQLITE_DEBUG)
259 # undef NDEBUG
260 #endif
261 
262 /*
263 ** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
264 */
265 #if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
266 # define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
267 #endif
268 
269 /*
270 ** The testcase() macro is used to aid in coverage testing.  When
271 ** doing coverage testing, the condition inside the argument to
272 ** testcase() must be evaluated both true and false in order to
273 ** get full branch coverage.  The testcase() macro is inserted
274 ** to help ensure adequate test coverage in places where simple
275 ** condition/decision coverage is inadequate.  For example, testcase()
276 ** can be used to make sure boundary values are tested.  For
277 ** bitmask tests, testcase() can be used to make sure each bit
278 ** is significant and used at least once.  On switch statements
279 ** where multiple cases go to the same block of code, testcase()
280 ** can insure that all cases are evaluated.
281 **
282 */
283 #ifdef SQLITE_COVERAGE_TEST
284   void sqlite3Coverage(int);
285 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
286 #else
287 # define testcase(X)
288 #endif
289 
290 /*
291 ** The TESTONLY macro is used to enclose variable declarations or
292 ** other bits of code that are needed to support the arguments
293 ** within testcase() and assert() macros.
294 */
295 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
296 # define TESTONLY(X)  X
297 #else
298 # define TESTONLY(X)
299 #endif
300 
301 /*
302 ** Sometimes we need a small amount of code such as a variable initialization
303 ** to setup for a later assert() statement.  We do not want this code to
304 ** appear when assert() is disabled.  The following macro is therefore
305 ** used to contain that setup code.  The "VVA" acronym stands for
306 ** "Verification, Validation, and Accreditation".  In other words, the
307 ** code within VVA_ONLY() will only run during verification processes.
308 */
309 #ifndef NDEBUG
310 # define VVA_ONLY(X)  X
311 #else
312 # define VVA_ONLY(X)
313 #endif
314 
315 /*
316 ** The ALWAYS and NEVER macros surround boolean expressions which
317 ** are intended to always be true or false, respectively.  Such
318 ** expressions could be omitted from the code completely.  But they
319 ** are included in a few cases in order to enhance the resilience
320 ** of SQLite to unexpected behavior - to make the code "self-healing"
321 ** or "ductile" rather than being "brittle" and crashing at the first
322 ** hint of unplanned behavior.
323 **
324 ** In other words, ALWAYS and NEVER are added for defensive code.
325 **
326 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
327 ** be true and false so that the unreachable code they specify will
328 ** not be counted as untested code.
329 */
330 #if defined(SQLITE_COVERAGE_TEST)
331 # define ALWAYS(X)      (1)
332 # define NEVER(X)       (0)
333 #elif !defined(NDEBUG)
334 # define ALWAYS(X)      ((X)?1:(assert(0),0))
335 # define NEVER(X)       ((X)?(assert(0),1):0)
336 #else
337 # define ALWAYS(X)      (X)
338 # define NEVER(X)       (X)
339 #endif
340 
341 /*
342 ** Return true (non-zero) if the input is a integer that is too large
343 ** to fit in 32-bits.  This macro is used inside of various testcase()
344 ** macros to verify that we have tested SQLite for large-file support.
345 */
346 #define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
347 
348 /*
349 ** The macro unlikely() is a hint that surrounds a boolean
350 ** expression that is usually false.  Macro likely() surrounds
351 ** a boolean expression that is usually true.  These hints could,
352 ** in theory, be used by the compiler to generate better code, but
353 ** currently they are just comments for human readers.
354 */
355 #define likely(X)    (X)
356 #define unlikely(X)  (X)
357 
358 #include "hash.h"
359 #include "parse.h"
360 #include <stdio.h>
361 #include <stdlib.h>
362 #include <string.h>
363 #include <assert.h>
364 #include <stddef.h>
365 
366 /*
367 ** If compiling for a processor that lacks floating point support,
368 ** substitute integer for floating-point
369 */
370 #ifdef SQLITE_OMIT_FLOATING_POINT
371 # define double sqlite_int64
372 # define float sqlite_int64
373 # define LONGDOUBLE_TYPE sqlite_int64
374 # ifndef SQLITE_BIG_DBL
375 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
376 # endif
377 # define SQLITE_OMIT_DATETIME_FUNCS 1
378 # define SQLITE_OMIT_TRACE 1
379 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
380 # undef SQLITE_HAVE_ISNAN
381 #endif
382 #ifndef SQLITE_BIG_DBL
383 # define SQLITE_BIG_DBL (1e99)
384 #endif
385 
386 /*
387 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
388 ** afterward. Having this macro allows us to cause the C compiler
389 ** to omit code used by TEMP tables without messy #ifndef statements.
390 */
391 #ifdef SQLITE_OMIT_TEMPDB
392 #define OMIT_TEMPDB 1
393 #else
394 #define OMIT_TEMPDB 0
395 #endif
396 
397 /*
398 ** The "file format" number is an integer that is incremented whenever
399 ** the VDBE-level file format changes.  The following macros define the
400 ** the default file format for new databases and the maximum file format
401 ** that the library can read.
402 */
403 #define SQLITE_MAX_FILE_FORMAT 4
404 #ifndef SQLITE_DEFAULT_FILE_FORMAT
405 # define SQLITE_DEFAULT_FILE_FORMAT 4
406 #endif
407 
408 /*
409 ** Determine whether triggers are recursive by default.  This can be
410 ** changed at run-time using a pragma.
411 */
412 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
413 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
414 #endif
415 
416 /*
417 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
418 ** on the command-line
419 */
420 #ifndef SQLITE_TEMP_STORE
421 # define SQLITE_TEMP_STORE 1
422 # define SQLITE_TEMP_STORE_xc 1  /* Exclude from ctime.c */
423 #endif
424 
425 /*
426 ** GCC does not define the offsetof() macro so we'll have to do it
427 ** ourselves.
428 */
429 #ifndef offsetof
430 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
431 #endif
432 
433 /*
434 ** Macros to compute minimum and maximum of two numbers.
435 */
436 #define MIN(A,B) ((A)<(B)?(A):(B))
437 #define MAX(A,B) ((A)>(B)?(A):(B))
438 
439 /*
440 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
441 ** not, there are still machines out there that use EBCDIC.)
442 */
443 #if 'A' == '\301'
444 # define SQLITE_EBCDIC 1
445 #else
446 # define SQLITE_ASCII 1
447 #endif
448 
449 /*
450 ** Integers of known sizes.  These typedefs might change for architectures
451 ** where the sizes very.  Preprocessor macros are available so that the
452 ** types can be conveniently redefined at compile-type.  Like this:
453 **
454 **         cc '-DUINTPTR_TYPE=long long int' ...
455 */
456 #ifndef UINT32_TYPE
457 # ifdef HAVE_UINT32_T
458 #  define UINT32_TYPE uint32_t
459 # else
460 #  define UINT32_TYPE unsigned int
461 # endif
462 #endif
463 #ifndef UINT16_TYPE
464 # ifdef HAVE_UINT16_T
465 #  define UINT16_TYPE uint16_t
466 # else
467 #  define UINT16_TYPE unsigned short int
468 # endif
469 #endif
470 #ifndef INT16_TYPE
471 # ifdef HAVE_INT16_T
472 #  define INT16_TYPE int16_t
473 # else
474 #  define INT16_TYPE short int
475 # endif
476 #endif
477 #ifndef UINT8_TYPE
478 # ifdef HAVE_UINT8_T
479 #  define UINT8_TYPE uint8_t
480 # else
481 #  define UINT8_TYPE unsigned char
482 # endif
483 #endif
484 #ifndef INT8_TYPE
485 # ifdef HAVE_INT8_T
486 #  define INT8_TYPE int8_t
487 # else
488 #  define INT8_TYPE signed char
489 # endif
490 #endif
491 #ifndef LONGDOUBLE_TYPE
492 # define LONGDOUBLE_TYPE long double
493 #endif
494 typedef sqlite_int64 i64;          /* 8-byte signed integer */
495 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
496 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
497 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
498 typedef INT16_TYPE i16;            /* 2-byte signed integer */
499 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
500 typedef INT8_TYPE i8;              /* 1-byte signed integer */
501 
502 /*
503 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
504 ** that can be stored in a u32 without loss of data.  The value
505 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
506 ** have to specify the value in the less intuitive manner shown:
507 */
508 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
509 
510 /*
511 ** The datatype used to store estimates of the number of rows in a
512 ** table or index.  This is an unsigned integer type.  For 99.9% of
513 ** the world, a 32-bit integer is sufficient.  But a 64-bit integer
514 ** can be used at compile-time if desired.
515 */
516 #ifdef SQLITE_64BIT_STATS
517  typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
518 #else
519  typedef u32 tRowcnt;    /* 32-bit is the default */
520 #endif
521 
522 /*
523 ** Estimated quantities used for query planning are stored as 16-bit
524 ** logarithms.  For quantity X, the value stored is 10*log2(X).  This
525 ** gives a possible range of values of approximately 1.0e986 to 1e-986.
526 ** But the allowed values are "grainy".  Not every value is representable.
527 ** For example, quantities 16 and 17 are both represented by a LogEst
528 ** of 40.  However, since LogEst quantaties are suppose to be estimates,
529 ** not exact values, this imprecision is not a problem.
530 **
531 ** "LogEst" is short for "Logarithmic Estimate".
532 **
533 ** Examples:
534 **      1 -> 0              20 -> 43          10000 -> 132
535 **      2 -> 10             25 -> 46          25000 -> 146
536 **      3 -> 16            100 -> 66        1000000 -> 199
537 **      4 -> 20           1000 -> 99        1048576 -> 200
538 **     10 -> 33           1024 -> 100    4294967296 -> 320
539 **
540 ** The LogEst can be negative to indicate fractional values.
541 ** Examples:
542 **
543 **    0.5 -> -10           0.1 -> -33        0.0625 -> -40
544 */
545 typedef INT16_TYPE LogEst;
546 
547 /*
548 ** Macros to determine whether the machine is big or little endian,
549 ** and whether or not that determination is run-time or compile-time.
550 **
551 ** For best performance, an attempt is made to guess at the byte-order
552 ** using C-preprocessor macros.  If that is unsuccessful, or if
553 ** -DSQLITE_RUNTIME_BYTEORDER=1 is set, then byte-order is determined
554 ** at run-time.
555 */
556 #ifdef SQLITE_AMALGAMATION
557 const int sqlite3one = 1;
558 #else
559 extern const int sqlite3one;
560 #endif
561 #if (defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
562      defined(__x86_64) || defined(__x86_64__) || defined(_M_X64)  ||    \
563      defined(_M_AMD64) || defined(_M_ARM)     || defined(__x86)   ||    \
564      defined(__arm__)) && !defined(SQLITE_RUNTIME_BYTEORDER)
565 # define SQLITE_BYTEORDER    1234
566 # define SQLITE_BIGENDIAN    0
567 # define SQLITE_LITTLEENDIAN 1
568 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
569 #endif
570 #if (defined(sparc)    || defined(__ppc__))  \
571     && !defined(SQLITE_RUNTIME_BYTEORDER)
572 # define SQLITE_BYTEORDER    4321
573 # define SQLITE_BIGENDIAN    1
574 # define SQLITE_LITTLEENDIAN 0
575 # define SQLITE_UTF16NATIVE  SQLITE_UTF16BE
576 #endif
577 #if !defined(SQLITE_BYTEORDER)
578 # define SQLITE_BYTEORDER    0     /* 0 means "unknown at compile-time" */
579 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
580 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
581 # define SQLITE_UTF16NATIVE  (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
582 #endif
583 
584 /*
585 ** Constants for the largest and smallest possible 64-bit signed integers.
586 ** These macros are designed to work correctly on both 32-bit and 64-bit
587 ** compilers.
588 */
589 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
590 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
591 
592 /*
593 ** Round up a number to the next larger multiple of 8.  This is used
594 ** to force 8-byte alignment on 64-bit architectures.
595 */
596 #define ROUND8(x)     (((x)+7)&~7)
597 
598 /*
599 ** Round down to the nearest multiple of 8
600 */
601 #define ROUNDDOWN8(x) ((x)&~7)
602 
603 /*
604 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
605 ** macro is used only within assert() to verify that the code gets
606 ** all alignment restrictions correct.
607 **
608 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
609 ** underlying malloc() implemention might return us 4-byte aligned
610 ** pointers.  In that case, only verify 4-byte alignment.
611 */
612 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
613 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
614 #else
615 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
616 #endif
617 
618 /*
619 ** Disable MMAP on platforms where it is known to not work
620 */
621 #if defined(__OpenBSD__) || defined(__QNXNTO__)
622 # undef SQLITE_MAX_MMAP_SIZE
623 # define SQLITE_MAX_MMAP_SIZE 0
624 #endif
625 
626 /*
627 ** Default maximum size of memory used by memory-mapped I/O in the VFS
628 */
629 #ifdef __APPLE__
630 # include <TargetConditionals.h>
631 # if TARGET_OS_IPHONE
632 #   undef SQLITE_MAX_MMAP_SIZE
633 #   define SQLITE_MAX_MMAP_SIZE 0
634 # endif
635 #endif
636 #ifndef SQLITE_MAX_MMAP_SIZE
637 # if defined(__linux__) \
638   || defined(_WIN32) \
639   || (defined(__APPLE__) && defined(__MACH__)) \
640   || defined(__sun)
641 #   define SQLITE_MAX_MMAP_SIZE 0x7fff0000  /* 2147418112 */
642 # else
643 #   define SQLITE_MAX_MMAP_SIZE 0
644 # endif
645 # define SQLITE_MAX_MMAP_SIZE_xc 1 /* exclude from ctime.c */
646 #endif
647 
648 /*
649 ** The default MMAP_SIZE is zero on all platforms.  Or, even if a larger
650 ** default MMAP_SIZE is specified at compile-time, make sure that it does
651 ** not exceed the maximum mmap size.
652 */
653 #ifndef SQLITE_DEFAULT_MMAP_SIZE
654 # define SQLITE_DEFAULT_MMAP_SIZE 0
655 # define SQLITE_DEFAULT_MMAP_SIZE_xc 1  /* Exclude from ctime.c */
656 #endif
657 #if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
658 # undef SQLITE_DEFAULT_MMAP_SIZE
659 # define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
660 #endif
661 
662 /*
663 ** Only one of SQLITE_ENABLE_STAT3 or SQLITE_ENABLE_STAT4 can be defined.
664 ** Priority is given to SQLITE_ENABLE_STAT4.  If either are defined, also
665 ** define SQLITE_ENABLE_STAT3_OR_STAT4
666 */
667 #ifdef SQLITE_ENABLE_STAT4
668 # undef SQLITE_ENABLE_STAT3
669 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
670 #elif SQLITE_ENABLE_STAT3
671 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
672 #elif SQLITE_ENABLE_STAT3_OR_STAT4
673 # undef SQLITE_ENABLE_STAT3_OR_STAT4
674 #endif
675 
676 /*
677 ** An instance of the following structure is used to store the busy-handler
678 ** callback for a given sqlite handle.
679 **
680 ** The sqlite.busyHandler member of the sqlite struct contains the busy
681 ** callback for the database handle. Each pager opened via the sqlite
682 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
683 ** callback is currently invoked only from within pager.c.
684 */
685 typedef struct BusyHandler BusyHandler;
686 struct BusyHandler {
687   int (*xFunc)(void *,int);  /* The busy callback */
688   void *pArg;                /* First arg to busy callback */
689   int nBusy;                 /* Incremented with each busy call */
690 };
691 
692 /*
693 ** Name of the master database table.  The master database table
694 ** is a special table that holds the names and attributes of all
695 ** user tables and indices.
696 */
697 #define MASTER_NAME       "sqlite_master"
698 #define TEMP_MASTER_NAME  "sqlite_temp_master"
699 
700 /*
701 ** The root-page of the master database table.
702 */
703 #define MASTER_ROOT       1
704 
705 /*
706 ** The name of the schema table.
707 */
708 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
709 
710 /*
711 ** A convenience macro that returns the number of elements in
712 ** an array.
713 */
714 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
715 
716 /*
717 ** Determine if the argument is a power of two
718 */
719 #define IsPowerOfTwo(X) (((X)&((X)-1))==0)
720 
721 /*
722 ** The following value as a destructor means to use sqlite3DbFree().
723 ** The sqlite3DbFree() routine requires two parameters instead of the
724 ** one parameter that destructors normally want.  So we have to introduce
725 ** this magic value that the code knows to handle differently.  Any
726 ** pointer will work here as long as it is distinct from SQLITE_STATIC
727 ** and SQLITE_TRANSIENT.
728 */
729 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3MallocSize)
730 
731 /*
732 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
733 ** not support Writable Static Data (WSD) such as global and static variables.
734 ** All variables must either be on the stack or dynamically allocated from
735 ** the heap.  When WSD is unsupported, the variable declarations scattered
736 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
737 ** macro is used for this purpose.  And instead of referencing the variable
738 ** directly, we use its constant as a key to lookup the run-time allocated
739 ** buffer that holds real variable.  The constant is also the initializer
740 ** for the run-time allocated buffer.
741 **
742 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
743 ** macros become no-ops and have zero performance impact.
744 */
745 #ifdef SQLITE_OMIT_WSD
746   #define SQLITE_WSD const
747   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
748   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
749   int sqlite3_wsd_init(int N, int J);
750   void *sqlite3_wsd_find(void *K, int L);
751 #else
752   #define SQLITE_WSD
753   #define GLOBAL(t,v) v
754   #define sqlite3GlobalConfig sqlite3Config
755 #endif
756 
757 /*
758 ** The following macros are used to suppress compiler warnings and to
759 ** make it clear to human readers when a function parameter is deliberately
760 ** left unused within the body of a function. This usually happens when
761 ** a function is called via a function pointer. For example the
762 ** implementation of an SQL aggregate step callback may not use the
763 ** parameter indicating the number of arguments passed to the aggregate,
764 ** if it knows that this is enforced elsewhere.
765 **
766 ** When a function parameter is not used at all within the body of a function,
767 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
768 ** However, these macros may also be used to suppress warnings related to
769 ** parameters that may or may not be used depending on compilation options.
770 ** For example those parameters only used in assert() statements. In these
771 ** cases the parameters are named as per the usual conventions.
772 */
773 #define UNUSED_PARAMETER(x) (void)(x)
774 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
775 
776 /*
777 ** Forward references to structures
778 */
779 typedef struct AggInfo AggInfo;
780 typedef struct AuthContext AuthContext;
781 typedef struct AutoincInfo AutoincInfo;
782 typedef struct Bitvec Bitvec;
783 typedef struct CollSeq CollSeq;
784 typedef struct Column Column;
785 typedef struct Db Db;
786 typedef struct Schema Schema;
787 typedef struct Expr Expr;
788 typedef struct ExprList ExprList;
789 typedef struct ExprSpan ExprSpan;
790 typedef struct FKey FKey;
791 typedef struct FuncDestructor FuncDestructor;
792 typedef struct FuncDef FuncDef;
793 typedef struct FuncDefHash FuncDefHash;
794 typedef struct IdList IdList;
795 typedef struct Index Index;
796 typedef struct IndexSample IndexSample;
797 typedef struct KeyClass KeyClass;
798 typedef struct KeyInfo KeyInfo;
799 typedef struct Lookaside Lookaside;
800 typedef struct LookasideSlot LookasideSlot;
801 typedef struct Module Module;
802 typedef struct NameContext NameContext;
803 typedef struct Parse Parse;
804 typedef struct PrintfArguments PrintfArguments;
805 typedef struct RowSet RowSet;
806 typedef struct Savepoint Savepoint;
807 typedef struct Select Select;
808 typedef struct SelectDest SelectDest;
809 typedef struct SrcList SrcList;
810 typedef struct StrAccum StrAccum;
811 typedef struct Table Table;
812 typedef struct TableLock TableLock;
813 typedef struct Token Token;
814 typedef struct Trigger Trigger;
815 typedef struct TriggerPrg TriggerPrg;
816 typedef struct TriggerStep TriggerStep;
817 typedef struct UnpackedRecord UnpackedRecord;
818 typedef struct VTable VTable;
819 typedef struct VtabCtx VtabCtx;
820 typedef struct Walker Walker;
821 typedef struct WhereInfo WhereInfo;
822 typedef struct With With;
823 
824 /*
825 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
826 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
827 ** pointer types (i.e. FuncDef) defined above.
828 */
829 #include "btree.h"
830 #include "vdbe.h"
831 #include "pager.h"
832 #include "pcache.h"
833 
834 #include "os.h"
835 #include "mutex.h"
836 
837 
838 /*
839 ** Each database file to be accessed by the system is an instance
840 ** of the following structure.  There are normally two of these structures
841 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
842 ** aDb[1] is the database file used to hold temporary tables.  Additional
843 ** databases may be attached.
844 */
845 struct Db {
846   char *zName;         /* Name of this database */
847   Btree *pBt;          /* The B*Tree structure for this database file */
848   u8 safety_level;     /* How aggressive at syncing data to disk */
849   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
850 };
851 
852 /*
853 ** An instance of the following structure stores a database schema.
854 **
855 ** Most Schema objects are associated with a Btree.  The exception is
856 ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
857 ** In shared cache mode, a single Schema object can be shared by multiple
858 ** Btrees that refer to the same underlying BtShared object.
859 **
860 ** Schema objects are automatically deallocated when the last Btree that
861 ** references them is destroyed.   The TEMP Schema is manually freed by
862 ** sqlite3_close().
863 *
864 ** A thread must be holding a mutex on the corresponding Btree in order
865 ** to access Schema content.  This implies that the thread must also be
866 ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
867 ** For a TEMP Schema, only the connection mutex is required.
868 */
869 struct Schema {
870   int schema_cookie;   /* Database schema version number for this file */
871   int iGeneration;     /* Generation counter.  Incremented with each change */
872   Hash tblHash;        /* All tables indexed by name */
873   Hash idxHash;        /* All (named) indices indexed by name */
874   Hash trigHash;       /* All triggers indexed by name */
875   Hash fkeyHash;       /* All foreign keys by referenced table name */
876   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
877   u8 file_format;      /* Schema format version for this file */
878   u8 enc;              /* Text encoding used by this database */
879   u16 flags;           /* Flags associated with this schema */
880   int cache_size;      /* Number of pages to use in the cache */
881 };
882 
883 /*
884 ** These macros can be used to test, set, or clear bits in the
885 ** Db.pSchema->flags field.
886 */
887 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->flags&(P))==(P))
888 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->flags&(P))!=0)
889 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->flags|=(P)
890 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->flags&=~(P)
891 
892 /*
893 ** Allowed values for the DB.pSchema->flags field.
894 **
895 ** The DB_SchemaLoaded flag is set after the database schema has been
896 ** read into internal hash tables.
897 **
898 ** DB_UnresetViews means that one or more views have column names that
899 ** have been filled out.  If the schema changes, these column names might
900 ** changes and so the view will need to be reset.
901 */
902 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
903 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
904 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
905 
906 /*
907 ** The number of different kinds of things that can be limited
908 ** using the sqlite3_limit() interface.
909 */
910 #define SQLITE_N_LIMIT (SQLITE_LIMIT_TRIGGER_DEPTH+1)
911 
912 /*
913 ** Lookaside malloc is a set of fixed-size buffers that can be used
914 ** to satisfy small transient memory allocation requests for objects
915 ** associated with a particular database connection.  The use of
916 ** lookaside malloc provides a significant performance enhancement
917 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
918 ** SQL statements.
919 **
920 ** The Lookaside structure holds configuration information about the
921 ** lookaside malloc subsystem.  Each available memory allocation in
922 ** the lookaside subsystem is stored on a linked list of LookasideSlot
923 ** objects.
924 **
925 ** Lookaside allocations are only allowed for objects that are associated
926 ** with a particular database connection.  Hence, schema information cannot
927 ** be stored in lookaside because in shared cache mode the schema information
928 ** is shared by multiple database connections.  Therefore, while parsing
929 ** schema information, the Lookaside.bEnabled flag is cleared so that
930 ** lookaside allocations are not used to construct the schema objects.
931 */
932 struct Lookaside {
933   u16 sz;                 /* Size of each buffer in bytes */
934   u8 bEnabled;            /* False to disable new lookaside allocations */
935   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
936   int nOut;               /* Number of buffers currently checked out */
937   int mxOut;              /* Highwater mark for nOut */
938   int anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
939   LookasideSlot *pFree;   /* List of available buffers */
940   void *pStart;           /* First byte of available memory space */
941   void *pEnd;             /* First byte past end of available space */
942 };
943 struct LookasideSlot {
944   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
945 };
946 
947 /*
948 ** A hash table for function definitions.
949 **
950 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
951 ** Collisions are on the FuncDef.pHash chain.
952 */
953 struct FuncDefHash {
954   FuncDef *a[23];       /* Hash table for functions */
955 };
956 
957 /*
958 ** Each database connection is an instance of the following structure.
959 */
960 struct sqlite3 {
961   sqlite3_vfs *pVfs;            /* OS Interface */
962   struct Vdbe *pVdbe;           /* List of active virtual machines */
963   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
964   sqlite3_mutex *mutex;         /* Connection mutex */
965   Db *aDb;                      /* All backends */
966   int nDb;                      /* Number of backends currently in use */
967   int flags;                    /* Miscellaneous flags. See below */
968   i64 lastRowid;                /* ROWID of most recent insert (see above) */
969   i64 szMmap;                   /* Default mmap_size setting */
970   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
971   int errCode;                  /* Most recent error code (SQLITE_*) */
972   int errMask;                  /* & result codes with this before returning */
973   u16 dbOptFlags;               /* Flags to enable/disable optimizations */
974   u8 autoCommit;                /* The auto-commit flag. */
975   u8 temp_store;                /* 1: file 2: memory 0: default */
976   u8 mallocFailed;              /* True if we have seen a malloc failure */
977   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
978   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
979   u8 suppressErr;               /* Do not issue error messages if true */
980   u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
981   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
982   int nextPagesize;             /* Pagesize after VACUUM if >0 */
983   u32 magic;                    /* Magic number for detect library misuse */
984   int nChange;                  /* Value returned by sqlite3_changes() */
985   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
986   int aLimit[SQLITE_N_LIMIT];   /* Limits */
987   struct sqlite3InitInfo {      /* Information used during initialization */
988     int newTnum;                /* Rootpage of table being initialized */
989     u8 iDb;                     /* Which db file is being initialized */
990     u8 busy;                    /* TRUE if currently initializing */
991     u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
992   } init;
993   int nVdbeActive;              /* Number of VDBEs currently running */
994   int nVdbeRead;                /* Number of active VDBEs that read or write */
995   int nVdbeWrite;               /* Number of active VDBEs that read and write */
996   int nVdbeExec;                /* Number of nested calls to VdbeExec() */
997   int nExtension;               /* Number of loaded extensions */
998   void **aExtension;            /* Array of shared library handles */
999   void (*xTrace)(void*,const char*);        /* Trace function */
1000   void *pTraceArg;                          /* Argument to the trace function */
1001   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
1002   void *pProfileArg;                        /* Argument to profile function */
1003   void *pCommitArg;                 /* Argument to xCommitCallback() */
1004   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
1005   void *pRollbackArg;               /* Argument to xRollbackCallback() */
1006   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
1007   void *pUpdateArg;
1008   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
1009 #ifndef SQLITE_OMIT_WAL
1010   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
1011   void *pWalArg;
1012 #endif
1013   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
1014   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
1015   void *pCollNeededArg;
1016   sqlite3_value *pErr;          /* Most recent error message */
1017   union {
1018     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
1019     double notUsed1;            /* Spacer */
1020   } u1;
1021   Lookaside lookaside;          /* Lookaside malloc configuration */
1022 #ifndef SQLITE_OMIT_AUTHORIZATION
1023   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
1024                                 /* Access authorization function */
1025   void *pAuthArg;               /* 1st argument to the access auth function */
1026 #endif
1027 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
1028   int (*xProgress)(void *);     /* The progress callback */
1029   void *pProgressArg;           /* Argument to the progress callback */
1030   unsigned nProgressOps;        /* Number of opcodes for progress callback */
1031 #endif
1032 #ifndef SQLITE_OMIT_VIRTUALTABLE
1033   int nVTrans;                  /* Allocated size of aVTrans */
1034   Hash aModule;                 /* populated by sqlite3_create_module() */
1035   VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
1036   VTable **aVTrans;             /* Virtual tables with open transactions */
1037   VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
1038 #endif
1039   FuncDefHash aFunc;            /* Hash table of connection functions */
1040   Hash aCollSeq;                /* All collating sequences */
1041   BusyHandler busyHandler;      /* Busy callback */
1042   Db aDbStatic[2];              /* Static space for the 2 default backends */
1043   Savepoint *pSavepoint;        /* List of active savepoints */
1044   int busyTimeout;              /* Busy handler timeout, in msec */
1045   int nSavepoint;               /* Number of non-transaction savepoints */
1046   int nStatement;               /* Number of nested statement-transactions  */
1047   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
1048   i64 nDeferredImmCons;         /* Net deferred immediate constraints */
1049   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
1050 
1051 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
1052   /* The following variables are all protected by the STATIC_MASTER
1053   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
1054   **
1055   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
1056   ** unlock so that it can proceed.
1057   **
1058   ** When X.pBlockingConnection==Y, that means that something that X tried
1059   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
1060   ** held by Y.
1061   */
1062   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
1063   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
1064   void *pUnlockArg;                     /* Argument to xUnlockNotify */
1065   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
1066   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
1067 #endif
1068 };
1069 
1070 /*
1071 ** A macro to discover the encoding of a database.
1072 */
1073 #define ENC(db) ((db)->aDb[0].pSchema->enc)
1074 
1075 /*
1076 ** Possible values for the sqlite3.flags.
1077 */
1078 #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
1079 #define SQLITE_InternChanges  0x00000002  /* Uncommitted Hash table changes */
1080 #define SQLITE_FullFSync      0x00000004  /* Use full fsync on the backend */
1081 #define SQLITE_CkptFullFSync  0x00000008  /* Use full fsync for checkpoint */
1082 #define SQLITE_CacheSpill     0x00000010  /* OK to spill pager cache */
1083 #define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
1084 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
1085 #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
1086                                           /*   DELETE, or UPDATE and return */
1087                                           /*   the count using a callback. */
1088 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
1089                                           /*   result set is empty */
1090 #define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
1091 #define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
1092 #define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
1093 #define SQLITE_VdbeAddopTrace 0x00001000  /* Trace sqlite3VdbeAddOp() calls */
1094 #define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
1095 #define SQLITE_ReadUncommitted 0x0004000  /* For shared-cache mode */
1096 #define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
1097 #define SQLITE_RecoveryMode   0x00010000  /* Ignore schema errors */
1098 #define SQLITE_ReverseOrder   0x00020000  /* Reverse unordered SELECTs */
1099 #define SQLITE_RecTriggers    0x00040000  /* Enable recursive triggers */
1100 #define SQLITE_ForeignKeys    0x00080000  /* Enforce foreign key constraints  */
1101 #define SQLITE_AutoIndex      0x00100000  /* Enable automatic indexes */
1102 #define SQLITE_PreferBuiltin  0x00200000  /* Preference to built-in funcs */
1103 #define SQLITE_LoadExtension  0x00400000  /* Enable load_extension */
1104 #define SQLITE_EnableTrigger  0x00800000  /* True to enable triggers */
1105 #define SQLITE_DeferFKs       0x01000000  /* Defer all FK constraints */
1106 #define SQLITE_QueryOnly      0x02000000  /* Disable database changes */
1107 #define SQLITE_VdbeEQP        0x04000000  /* Debug EXPLAIN QUERY PLAN */
1108 
1109 
1110 /*
1111 ** Bits of the sqlite3.dbOptFlags field that are used by the
1112 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
1113 ** selectively disable various optimizations.
1114 */
1115 #define SQLITE_QueryFlattener 0x0001   /* Query flattening */
1116 #define SQLITE_ColumnCache    0x0002   /* Column cache */
1117 #define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
1118 #define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
1119 /*                not used    0x0010   // Was: SQLITE_IdxRealAsInt */
1120 #define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
1121 #define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
1122 #define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
1123 #define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
1124 #define SQLITE_Transitive     0x0200   /* Transitive constraints */
1125 #define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
1126 #define SQLITE_Stat3          0x0800   /* Use the SQLITE_STAT3 table */
1127 #define SQLITE_AdjustOutEst   0x1000   /* Adjust output estimates using WHERE */
1128 #define SQLITE_AllOpts        0xffff   /* All optimizations */
1129 
1130 /*
1131 ** Macros for testing whether or not optimizations are enabled or disabled.
1132 */
1133 #ifndef SQLITE_OMIT_BUILTIN_TEST
1134 #define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
1135 #define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
1136 #else
1137 #define OptimizationDisabled(db, mask)  0
1138 #define OptimizationEnabled(db, mask)   1
1139 #endif
1140 
1141 /*
1142 ** Return true if it OK to factor constant expressions into the initialization
1143 ** code. The argument is a Parse object for the code generator.
1144 */
1145 #define ConstFactorOk(P) ((P)->okConstFactor)
1146 
1147 /*
1148 ** Possible values for the sqlite.magic field.
1149 ** The numbers are obtained at random and have no special meaning, other
1150 ** than being distinct from one another.
1151 */
1152 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
1153 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
1154 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
1155 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
1156 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
1157 #define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */
1158 
1159 /*
1160 ** Each SQL function is defined by an instance of the following
1161 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
1162 ** hash table.  When multiple functions have the same name, the hash table
1163 ** points to a linked list of these structures.
1164 */
1165 struct FuncDef {
1166   i16 nArg;            /* Number of arguments.  -1 means unlimited */
1167   u16 funcFlags;       /* Some combination of SQLITE_FUNC_* */
1168   void *pUserData;     /* User data parameter */
1169   FuncDef *pNext;      /* Next function with same name */
1170   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
1171   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
1172   void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
1173   char *zName;         /* SQL name of the function. */
1174   FuncDef *pHash;      /* Next with a different name but the same hash */
1175   FuncDestructor *pDestructor;   /* Reference counted destructor function */
1176 };
1177 
1178 /*
1179 ** This structure encapsulates a user-function destructor callback (as
1180 ** configured using create_function_v2()) and a reference counter. When
1181 ** create_function_v2() is called to create a function with a destructor,
1182 ** a single object of this type is allocated. FuncDestructor.nRef is set to
1183 ** the number of FuncDef objects created (either 1 or 3, depending on whether
1184 ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
1185 ** member of each of the new FuncDef objects is set to point to the allocated
1186 ** FuncDestructor.
1187 **
1188 ** Thereafter, when one of the FuncDef objects is deleted, the reference
1189 ** count on this object is decremented. When it reaches 0, the destructor
1190 ** is invoked and the FuncDestructor structure freed.
1191 */
1192 struct FuncDestructor {
1193   int nRef;
1194   void (*xDestroy)(void *);
1195   void *pUserData;
1196 };
1197 
1198 /*
1199 ** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
1200 ** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  There
1201 ** are assert() statements in the code to verify this.
1202 */
1203 #define SQLITE_FUNC_ENCMASK  0x003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
1204 #define SQLITE_FUNC_LIKE     0x004 /* Candidate for the LIKE optimization */
1205 #define SQLITE_FUNC_CASE     0x008 /* Case-sensitive LIKE-type function */
1206 #define SQLITE_FUNC_EPHEM    0x010 /* Ephemeral.  Delete with VDBE */
1207 #define SQLITE_FUNC_NEEDCOLL 0x020 /* sqlite3GetFuncCollSeq() might be called */
1208 #define SQLITE_FUNC_LENGTH   0x040 /* Built-in length() function */
1209 #define SQLITE_FUNC_TYPEOF   0x080 /* Built-in typeof() function */
1210 #define SQLITE_FUNC_COUNT    0x100 /* Built-in count(*) aggregate */
1211 #define SQLITE_FUNC_COALESCE 0x200 /* Built-in coalesce() or ifnull() */
1212 #define SQLITE_FUNC_UNLIKELY 0x400 /* Built-in unlikely() function */
1213 #define SQLITE_FUNC_CONSTANT 0x800 /* Constant inputs give a constant output */
1214 
1215 /*
1216 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
1217 ** used to create the initializers for the FuncDef structures.
1218 **
1219 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
1220 **     Used to create a scalar function definition of a function zName
1221 **     implemented by C function xFunc that accepts nArg arguments. The
1222 **     value passed as iArg is cast to a (void*) and made available
1223 **     as the user-data (sqlite3_user_data()) for the function. If
1224 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
1225 **
1226 **   VFUNCTION(zName, nArg, iArg, bNC, xFunc)
1227 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
1228 **
1229 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
1230 **     Used to create an aggregate function definition implemented by
1231 **     the C functions xStep and xFinal. The first four parameters
1232 **     are interpreted in the same way as the first 4 parameters to
1233 **     FUNCTION().
1234 **
1235 **   LIKEFUNC(zName, nArg, pArg, flags)
1236 **     Used to create a scalar function definition of a function zName
1237 **     that accepts nArg arguments and is implemented by a call to C
1238 **     function likeFunc. Argument pArg is cast to a (void *) and made
1239 **     available as the function user-data (sqlite3_user_data()). The
1240 **     FuncDef.flags variable is set to the value passed as the flags
1241 **     parameter.
1242 */
1243 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1244   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1245    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1246 #define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1247   {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1248    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1249 #define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
1250   {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
1251    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1252 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
1253   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1254    pArg, 0, xFunc, 0, 0, #zName, 0, 0}
1255 #define LIKEFUNC(zName, nArg, arg, flags) \
1256   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
1257    (void *)arg, 0, likeFunc, 0, 0, #zName, 0, 0}
1258 #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
1259   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
1260    SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}
1261 
1262 /*
1263 ** All current savepoints are stored in a linked list starting at
1264 ** sqlite3.pSavepoint. The first element in the list is the most recently
1265 ** opened savepoint. Savepoints are added to the list by the vdbe
1266 ** OP_Savepoint instruction.
1267 */
1268 struct Savepoint {
1269   char *zName;                        /* Savepoint name (nul-terminated) */
1270   i64 nDeferredCons;                  /* Number of deferred fk violations */
1271   i64 nDeferredImmCons;               /* Number of deferred imm fk. */
1272   Savepoint *pNext;                   /* Parent savepoint (if any) */
1273 };
1274 
1275 /*
1276 ** The following are used as the second parameter to sqlite3Savepoint(),
1277 ** and as the P1 argument to the OP_Savepoint instruction.
1278 */
1279 #define SAVEPOINT_BEGIN      0
1280 #define SAVEPOINT_RELEASE    1
1281 #define SAVEPOINT_ROLLBACK   2
1282 
1283 
1284 /*
1285 ** Each SQLite module (virtual table definition) is defined by an
1286 ** instance of the following structure, stored in the sqlite3.aModule
1287 ** hash table.
1288 */
1289 struct Module {
1290   const sqlite3_module *pModule;       /* Callback pointers */
1291   const char *zName;                   /* Name passed to create_module() */
1292   void *pAux;                          /* pAux passed to create_module() */
1293   void (*xDestroy)(void *);            /* Module destructor function */
1294 };
1295 
1296 /*
1297 ** information about each column of an SQL table is held in an instance
1298 ** of this structure.
1299 */
1300 struct Column {
1301   char *zName;     /* Name of this column */
1302   Expr *pDflt;     /* Default value of this column */
1303   char *zDflt;     /* Original text of the default value */
1304   char *zType;     /* Data type for this column */
1305   char *zColl;     /* Collating sequence.  If NULL, use the default */
1306   u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
1307   char affinity;   /* One of the SQLITE_AFF_... values */
1308   u8 szEst;        /* Estimated size of this column.  INT==1 */
1309   u8 colFlags;     /* Boolean properties.  See COLFLAG_ defines below */
1310 };
1311 
1312 /* Allowed values for Column.colFlags:
1313 */
1314 #define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
1315 #define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */
1316 
1317 /*
1318 ** A "Collating Sequence" is defined by an instance of the following
1319 ** structure. Conceptually, a collating sequence consists of a name and
1320 ** a comparison routine that defines the order of that sequence.
1321 **
1322 ** If CollSeq.xCmp is NULL, it means that the
1323 ** collating sequence is undefined.  Indices built on an undefined
1324 ** collating sequence may not be read or written.
1325 */
1326 struct CollSeq {
1327   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
1328   u8 enc;               /* Text encoding handled by xCmp() */
1329   void *pUser;          /* First argument to xCmp() */
1330   int (*xCmp)(void*,int, const void*, int, const void*);
1331   void (*xDel)(void*);  /* Destructor for pUser */
1332 };
1333 
1334 /*
1335 ** A sort order can be either ASC or DESC.
1336 */
1337 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
1338 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
1339 
1340 /*
1341 ** Column affinity types.
1342 **
1343 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
1344 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
1345 ** the speed a little by numbering the values consecutively.
1346 **
1347 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
1348 ** when multiple affinity types are concatenated into a string and
1349 ** used as the P4 operand, they will be more readable.
1350 **
1351 ** Note also that the numeric types are grouped together so that testing
1352 ** for a numeric type is a single comparison.
1353 */
1354 #define SQLITE_AFF_TEXT     'a'
1355 #define SQLITE_AFF_NONE     'b'
1356 #define SQLITE_AFF_NUMERIC  'c'
1357 #define SQLITE_AFF_INTEGER  'd'
1358 #define SQLITE_AFF_REAL     'e'
1359 
1360 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
1361 
1362 /*
1363 ** The SQLITE_AFF_MASK values masks off the significant bits of an
1364 ** affinity value.
1365 */
1366 #define SQLITE_AFF_MASK     0x67
1367 
1368 /*
1369 ** Additional bit values that can be ORed with an affinity without
1370 ** changing the affinity.
1371 **
1372 ** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
1373 ** It causes an assert() to fire if either operand to a comparison
1374 ** operator is NULL.  It is added to certain comparison operators to
1375 ** prove that the operands are always NOT NULL.
1376 */
1377 #define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
1378 #define SQLITE_STOREP2      0x10  /* Store result in reg[P2] rather than jump */
1379 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
1380 #define SQLITE_NOTNULL      0x88  /* Assert that operands are never NULL */
1381 
1382 /*
1383 ** An object of this type is created for each virtual table present in
1384 ** the database schema.
1385 **
1386 ** If the database schema is shared, then there is one instance of this
1387 ** structure for each database connection (sqlite3*) that uses the shared
1388 ** schema. This is because each database connection requires its own unique
1389 ** instance of the sqlite3_vtab* handle used to access the virtual table
1390 ** implementation. sqlite3_vtab* handles can not be shared between
1391 ** database connections, even when the rest of the in-memory database
1392 ** schema is shared, as the implementation often stores the database
1393 ** connection handle passed to it via the xConnect() or xCreate() method
1394 ** during initialization internally. This database connection handle may
1395 ** then be used by the virtual table implementation to access real tables
1396 ** within the database. So that they appear as part of the callers
1397 ** transaction, these accesses need to be made via the same database
1398 ** connection as that used to execute SQL operations on the virtual table.
1399 **
1400 ** All VTable objects that correspond to a single table in a shared
1401 ** database schema are initially stored in a linked-list pointed to by
1402 ** the Table.pVTable member variable of the corresponding Table object.
1403 ** When an sqlite3_prepare() operation is required to access the virtual
1404 ** table, it searches the list for the VTable that corresponds to the
1405 ** database connection doing the preparing so as to use the correct
1406 ** sqlite3_vtab* handle in the compiled query.
1407 **
1408 ** When an in-memory Table object is deleted (for example when the
1409 ** schema is being reloaded for some reason), the VTable objects are not
1410 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
1411 ** immediately. Instead, they are moved from the Table.pVTable list to
1412 ** another linked list headed by the sqlite3.pDisconnect member of the
1413 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
1414 ** next time a statement is prepared using said sqlite3*. This is done
1415 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
1416 ** Refer to comments above function sqlite3VtabUnlockList() for an
1417 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
1418 ** list without holding the corresponding sqlite3.mutex mutex.
1419 **
1420 ** The memory for objects of this type is always allocated by
1421 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
1422 ** the first argument.
1423 */
1424 struct VTable {
1425   sqlite3 *db;              /* Database connection associated with this table */
1426   Module *pMod;             /* Pointer to module implementation */
1427   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
1428   int nRef;                 /* Number of pointers to this structure */
1429   u8 bConstraint;           /* True if constraints are supported */
1430   int iSavepoint;           /* Depth of the SAVEPOINT stack */
1431   VTable *pNext;            /* Next in linked list (see above) */
1432 };
1433 
1434 /*
1435 ** Each SQL table is represented in memory by an instance of the
1436 ** following structure.
1437 **
1438 ** Table.zName is the name of the table.  The case of the original
1439 ** CREATE TABLE statement is stored, but case is not significant for
1440 ** comparisons.
1441 **
1442 ** Table.nCol is the number of columns in this table.  Table.aCol is a
1443 ** pointer to an array of Column structures, one for each column.
1444 **
1445 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
1446 ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
1447 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
1448 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
1449 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
1450 ** is generated for each row of the table.  TF_HasPrimaryKey is set if
1451 ** the table has any PRIMARY KEY, INTEGER or otherwise.
1452 **
1453 ** Table.tnum is the page number for the root BTree page of the table in the
1454 ** database file.  If Table.iDb is the index of the database table backend
1455 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
1456 ** holds temporary tables and indices.  If TF_Ephemeral is set
1457 ** then the table is stored in a file that is automatically deleted
1458 ** when the VDBE cursor to the table is closed.  In this case Table.tnum
1459 ** refers VDBE cursor number that holds the table open, not to the root
1460 ** page number.  Transient tables are used to hold the results of a
1461 ** sub-query that appears instead of a real table name in the FROM clause
1462 ** of a SELECT statement.
1463 */
1464 struct Table {
1465   char *zName;         /* Name of the table or view */
1466   Column *aCol;        /* Information about each column */
1467   Index *pIndex;       /* List of SQL indexes on this table. */
1468   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
1469   FKey *pFKey;         /* Linked list of all foreign keys in this table */
1470   char *zColAff;       /* String defining the affinity of each column */
1471 #ifndef SQLITE_OMIT_CHECK
1472   ExprList *pCheck;    /* All CHECK constraints */
1473 #endif
1474   LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
1475   int tnum;            /* Root BTree node for this table (see note above) */
1476   i16 iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
1477   i16 nCol;            /* Number of columns in this table */
1478   u16 nRef;            /* Number of pointers to this Table */
1479   LogEst szTabRow;     /* Estimated size of each table row in bytes */
1480   u8 tabFlags;         /* Mask of TF_* values */
1481   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
1482 #ifndef SQLITE_OMIT_ALTERTABLE
1483   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
1484 #endif
1485 #ifndef SQLITE_OMIT_VIRTUALTABLE
1486   int nModuleArg;      /* Number of arguments to the module */
1487   char **azModuleArg;  /* Text of all module args. [0] is module name */
1488   VTable *pVTable;     /* List of VTable objects. */
1489 #endif
1490   Trigger *pTrigger;   /* List of triggers stored in pSchema */
1491   Schema *pSchema;     /* Schema that contains this table */
1492   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
1493 };
1494 
1495 /*
1496 ** Allowed values for Table.tabFlags.
1497 */
1498 #define TF_Readonly        0x01    /* Read-only system table */
1499 #define TF_Ephemeral       0x02    /* An ephemeral table */
1500 #define TF_HasPrimaryKey   0x04    /* Table has a primary key */
1501 #define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
1502 #define TF_Virtual         0x10    /* Is a virtual table */
1503 #define TF_WithoutRowid    0x20    /* No rowid used. PRIMARY KEY is the key */
1504 
1505 
1506 /*
1507 ** Test to see whether or not a table is a virtual table.  This is
1508 ** done as a macro so that it will be optimized out when virtual
1509 ** table support is omitted from the build.
1510 */
1511 #ifndef SQLITE_OMIT_VIRTUALTABLE
1512 #  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
1513 #  define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1514 #else
1515 #  define IsVirtual(X)      0
1516 #  define IsHiddenColumn(X) 0
1517 #endif
1518 
1519 /* Does the table have a rowid */
1520 #define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
1521 
1522 /*
1523 ** Each foreign key constraint is an instance of the following structure.
1524 **
1525 ** A foreign key is associated with two tables.  The "from" table is
1526 ** the table that contains the REFERENCES clause that creates the foreign
1527 ** key.  The "to" table is the table that is named in the REFERENCES clause.
1528 ** Consider this example:
1529 **
1530 **     CREATE TABLE ex1(
1531 **       a INTEGER PRIMARY KEY,
1532 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
1533 **     );
1534 **
1535 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
1536 ** Equivalent names:
1537 **
1538 **     from-table == child-table
1539 **       to-table == parent-table
1540 **
1541 ** Each REFERENCES clause generates an instance of the following structure
1542 ** which is attached to the from-table.  The to-table need not exist when
1543 ** the from-table is created.  The existence of the to-table is not checked.
1544 **
1545 ** The list of all parents for child Table X is held at X.pFKey.
1546 **
1547 ** A list of all children for a table named Z (which might not even exist)
1548 ** is held in Schema.fkeyHash with a hash key of Z.
1549 */
1550 struct FKey {
1551   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
1552   FKey *pNextFrom;  /* Next FKey with the same in pFrom. Next parent of pFrom */
1553   char *zTo;        /* Name of table that the key points to (aka: Parent) */
1554   FKey *pNextTo;    /* Next with the same zTo. Next child of zTo. */
1555   FKey *pPrevTo;    /* Previous with the same zTo */
1556   int nCol;         /* Number of columns in this key */
1557   /* EV: R-30323-21917 */
1558   u8 isDeferred;       /* True if constraint checking is deferred till COMMIT */
1559   u8 aAction[2];        /* ON DELETE and ON UPDATE actions, respectively */
1560   Trigger *apTrigger[2];/* Triggers for aAction[] actions */
1561   struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
1562     int iFrom;            /* Index of column in pFrom */
1563     char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
1564   } aCol[1];            /* One entry for each of nCol columns */
1565 };
1566 
1567 /*
1568 ** SQLite supports many different ways to resolve a constraint
1569 ** error.  ROLLBACK processing means that a constraint violation
1570 ** causes the operation in process to fail and for the current transaction
1571 ** to be rolled back.  ABORT processing means the operation in process
1572 ** fails and any prior changes from that one operation are backed out,
1573 ** but the transaction is not rolled back.  FAIL processing means that
1574 ** the operation in progress stops and returns an error code.  But prior
1575 ** changes due to the same operation are not backed out and no rollback
1576 ** occurs.  IGNORE means that the particular row that caused the constraint
1577 ** error is not inserted or updated.  Processing continues and no error
1578 ** is returned.  REPLACE means that preexisting database rows that caused
1579 ** a UNIQUE constraint violation are removed so that the new insert or
1580 ** update can proceed.  Processing continues and no error is reported.
1581 **
1582 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
1583 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
1584 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
1585 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
1586 ** referenced table row is propagated into the row that holds the
1587 ** foreign key.
1588 **
1589 ** The following symbolic values are used to record which type
1590 ** of action to take.
1591 */
1592 #define OE_None     0   /* There is no constraint to check */
1593 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
1594 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
1595 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
1596 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
1597 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
1598 
1599 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
1600 #define OE_SetNull  7   /* Set the foreign key value to NULL */
1601 #define OE_SetDflt  8   /* Set the foreign key value to its default */
1602 #define OE_Cascade  9   /* Cascade the changes */
1603 
1604 #define OE_Default  10  /* Do whatever the default action is */
1605 
1606 
1607 /*
1608 ** An instance of the following structure is passed as the first
1609 ** argument to sqlite3VdbeKeyCompare and is used to control the
1610 ** comparison of the two index keys.
1611 **
1612 ** Note that aSortOrder[] and aColl[] have nField+1 slots.  There
1613 ** are nField slots for the columns of an index then one extra slot
1614 ** for the rowid at the end.
1615 */
1616 struct KeyInfo {
1617   u32 nRef;           /* Number of references to this KeyInfo object */
1618   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
1619   u16 nField;         /* Number of key columns in the index */
1620   u16 nXField;        /* Number of columns beyond the key columns */
1621   sqlite3 *db;        /* The database connection */
1622   u8 *aSortOrder;     /* Sort order for each column. */
1623   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
1624 };
1625 
1626 /*
1627 ** An instance of the following structure holds information about a
1628 ** single index record that has already been parsed out into individual
1629 ** values.
1630 **
1631 ** A record is an object that contains one or more fields of data.
1632 ** Records are used to store the content of a table row and to store
1633 ** the key of an index.  A blob encoding of a record is created by
1634 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
1635 ** OP_Column opcode.
1636 **
1637 ** This structure holds a record that has already been disassembled
1638 ** into its constituent fields.
1639 **
1640 ** The r1 and r2 member variables are only used by the optimized comparison
1641 ** functions vdbeRecordCompareInt() and vdbeRecordCompareString().
1642 */
1643 struct UnpackedRecord {
1644   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
1645   u16 nField;         /* Number of entries in apMem[] */
1646   i8 default_rc;      /* Comparison result if keys are equal */
1647   u8 isCorrupt;       /* Corruption detected by xRecordCompare() */
1648   Mem *aMem;          /* Values */
1649   int r1;             /* Value to return if (lhs > rhs) */
1650   int r2;             /* Value to return if (rhs < lhs) */
1651 };
1652 
1653 
1654 /*
1655 ** Each SQL index is represented in memory by an
1656 ** instance of the following structure.
1657 **
1658 ** The columns of the table that are to be indexed are described
1659 ** by the aiColumn[] field of this structure.  For example, suppose
1660 ** we have the following table and index:
1661 **
1662 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
1663 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
1664 **
1665 ** In the Table structure describing Ex1, nCol==3 because there are
1666 ** three columns in the table.  In the Index structure describing
1667 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
1668 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
1669 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
1670 ** The second column to be indexed (c1) has an index of 0 in
1671 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
1672 **
1673 ** The Index.onError field determines whether or not the indexed columns
1674 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
1675 ** it means this is not a unique index.  Otherwise it is a unique index
1676 ** and the value of Index.onError indicate the which conflict resolution
1677 ** algorithm to employ whenever an attempt is made to insert a non-unique
1678 ** element.
1679 */
1680 struct Index {
1681   char *zName;             /* Name of this index */
1682   i16 *aiColumn;           /* Which columns are used by this index.  1st is 0 */
1683   LogEst *aiRowLogEst;     /* From ANALYZE: Est. rows selected by each column */
1684   Table *pTable;           /* The SQL table being indexed */
1685   char *zColAff;           /* String defining the affinity of each column */
1686   Index *pNext;            /* The next index associated with the same table */
1687   Schema *pSchema;         /* Schema containing this index */
1688   u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
1689   char **azColl;           /* Array of collation sequence names for index */
1690   Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
1691   KeyInfo *pKeyInfo;       /* A KeyInfo object suitable for this index */
1692   int tnum;                /* DB Page containing root of this index */
1693   LogEst szIdxRow;         /* Estimated average row size in bytes */
1694   u16 nKeyCol;             /* Number of columns forming the key */
1695   u16 nColumn;             /* Number of columns stored in the index */
1696   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
1697   unsigned autoIndex:2;    /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
1698   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
1699   unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
1700   unsigned isResized:1;    /* True if resizeIndexObject() has been called */
1701   unsigned isCovering:1;   /* True if this is a covering index */
1702 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
1703   int nSample;             /* Number of elements in aSample[] */
1704   int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
1705   tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
1706   IndexSample *aSample;    /* Samples of the left-most key */
1707 #endif
1708 };
1709 
1710 /*
1711 ** Each sample stored in the sqlite_stat3 table is represented in memory
1712 ** using a structure of this type.  See documentation at the top of the
1713 ** analyze.c source file for additional information.
1714 */
1715 struct IndexSample {
1716   void *p;          /* Pointer to sampled record */
1717   int n;            /* Size of record in bytes */
1718   tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
1719   tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
1720   tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
1721 };
1722 
1723 /*
1724 ** Each token coming out of the lexer is an instance of
1725 ** this structure.  Tokens are also used as part of an expression.
1726 **
1727 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
1728 ** may contain random values.  Do not make any assumptions about Token.dyn
1729 ** and Token.n when Token.z==0.
1730 */
1731 struct Token {
1732   const char *z;     /* Text of the token.  Not NULL-terminated! */
1733   unsigned int n;    /* Number of characters in this token */
1734 };
1735 
1736 /*
1737 ** An instance of this structure contains information needed to generate
1738 ** code for a SELECT that contains aggregate functions.
1739 **
1740 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
1741 ** pointer to this structure.  The Expr.iColumn field is the index in
1742 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
1743 ** code for that node.
1744 **
1745 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
1746 ** original Select structure that describes the SELECT statement.  These
1747 ** fields do not need to be freed when deallocating the AggInfo structure.
1748 */
1749 struct AggInfo {
1750   u8 directMode;          /* Direct rendering mode means take data directly
1751                           ** from source tables rather than from accumulators */
1752   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
1753                           ** than the source table */
1754   int sortingIdx;         /* Cursor number of the sorting index */
1755   int sortingIdxPTab;     /* Cursor number of pseudo-table */
1756   int nSortingColumn;     /* Number of columns in the sorting index */
1757   int mnReg, mxReg;       /* Range of registers allocated for aCol and aFunc */
1758   ExprList *pGroupBy;     /* The group by clause */
1759   struct AggInfo_col {    /* For each column used in source tables */
1760     Table *pTab;             /* Source table */
1761     int iTable;              /* Cursor number of the source table */
1762     int iColumn;             /* Column number within the source table */
1763     int iSorterColumn;       /* Column number in the sorting index */
1764     int iMem;                /* Memory location that acts as accumulator */
1765     Expr *pExpr;             /* The original expression */
1766   } *aCol;
1767   int nColumn;            /* Number of used entries in aCol[] */
1768   int nAccumulator;       /* Number of columns that show through to the output.
1769                           ** Additional columns are used only as parameters to
1770                           ** aggregate functions */
1771   struct AggInfo_func {   /* For each aggregate function */
1772     Expr *pExpr;             /* Expression encoding the function */
1773     FuncDef *pFunc;          /* The aggregate function implementation */
1774     int iMem;                /* Memory location that acts as accumulator */
1775     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
1776   } *aFunc;
1777   int nFunc;              /* Number of entries in aFunc[] */
1778 };
1779 
1780 /*
1781 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
1782 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
1783 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
1784 ** it uses less memory in the Expr object, which is a big memory user
1785 ** in systems with lots of prepared statements.  And few applications
1786 ** need more than about 10 or 20 variables.  But some extreme users want
1787 ** to have prepared statements with over 32767 variables, and for them
1788 ** the option is available (at compile-time).
1789 */
1790 #if SQLITE_MAX_VARIABLE_NUMBER<=32767
1791 typedef i16 ynVar;
1792 #else
1793 typedef int ynVar;
1794 #endif
1795 
1796 /*
1797 ** Each node of an expression in the parse tree is an instance
1798 ** of this structure.
1799 **
1800 ** Expr.op is the opcode. The integer parser token codes are reused
1801 ** as opcodes here. For example, the parser defines TK_GE to be an integer
1802 ** code representing the ">=" operator. This same integer code is reused
1803 ** to represent the greater-than-or-equal-to operator in the expression
1804 ** tree.
1805 **
1806 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
1807 ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
1808 ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
1809 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
1810 ** then Expr.token contains the name of the function.
1811 **
1812 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
1813 ** binary operator. Either or both may be NULL.
1814 **
1815 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
1816 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
1817 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
1818 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
1819 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
1820 ** valid.
1821 **
1822 ** An expression of the form ID or ID.ID refers to a column in a table.
1823 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
1824 ** the integer cursor number of a VDBE cursor pointing to that table and
1825 ** Expr.iColumn is the column number for the specific column.  If the
1826 ** expression is used as a result in an aggregate SELECT, then the
1827 ** value is also stored in the Expr.iAgg column in the aggregate so that
1828 ** it can be accessed after all aggregates are computed.
1829 **
1830 ** If the expression is an unbound variable marker (a question mark
1831 ** character '?' in the original SQL) then the Expr.iTable holds the index
1832 ** number for that variable.
1833 **
1834 ** If the expression is a subquery then Expr.iColumn holds an integer
1835 ** register number containing the result of the subquery.  If the
1836 ** subquery gives a constant result, then iTable is -1.  If the subquery
1837 ** gives a different answer at different times during statement processing
1838 ** then iTable is the address of a subroutine that computes the subquery.
1839 **
1840 ** If the Expr is of type OP_Column, and the table it is selecting from
1841 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
1842 ** corresponding table definition.
1843 **
1844 ** ALLOCATION NOTES:
1845 **
1846 ** Expr objects can use a lot of memory space in database schema.  To
1847 ** help reduce memory requirements, sometimes an Expr object will be
1848 ** truncated.  And to reduce the number of memory allocations, sometimes
1849 ** two or more Expr objects will be stored in a single memory allocation,
1850 ** together with Expr.zToken strings.
1851 **
1852 ** If the EP_Reduced and EP_TokenOnly flags are set when
1853 ** an Expr object is truncated.  When EP_Reduced is set, then all
1854 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
1855 ** are contained within the same memory allocation.  Note, however, that
1856 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
1857 ** allocated, regardless of whether or not EP_Reduced is set.
1858 */
1859 struct Expr {
1860   u8 op;                 /* Operation performed by this node */
1861   char affinity;         /* The affinity of the column or 0 if not a column */
1862   u32 flags;             /* Various flags.  EP_* See below */
1863   union {
1864     char *zToken;          /* Token value. Zero terminated and dequoted */
1865     int iValue;            /* Non-negative integer value if EP_IntValue */
1866   } u;
1867 
1868   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
1869   ** space is allocated for the fields below this point. An attempt to
1870   ** access them will result in a segfault or malfunction.
1871   *********************************************************************/
1872 
1873   Expr *pLeft;           /* Left subnode */
1874   Expr *pRight;          /* Right subnode */
1875   union {
1876     ExprList *pList;     /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
1877     Select *pSelect;     /* EP_xIsSelect and op = IN, EXISTS, SELECT */
1878   } x;
1879 
1880   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
1881   ** space is allocated for the fields below this point. An attempt to
1882   ** access them will result in a segfault or malfunction.
1883   *********************************************************************/
1884 
1885 #if SQLITE_MAX_EXPR_DEPTH>0
1886   int nHeight;           /* Height of the tree headed by this node */
1887 #endif
1888   int iTable;            /* TK_COLUMN: cursor number of table holding column
1889                          ** TK_REGISTER: register number
1890                          ** TK_TRIGGER: 1 -> new, 0 -> old
1891                          ** EP_Unlikely:  1000 times likelihood */
1892   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
1893                          ** TK_VARIABLE: variable number (always >= 1). */
1894   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
1895   i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
1896   u8 op2;                /* TK_REGISTER: original value of Expr.op
1897                          ** TK_COLUMN: the value of p5 for OP_Column
1898                          ** TK_AGG_FUNCTION: nesting depth */
1899   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
1900   Table *pTab;           /* Table for TK_COLUMN expressions. */
1901 };
1902 
1903 /*
1904 ** The following are the meanings of bits in the Expr.flags field.
1905 */
1906 #define EP_FromJoin  0x000001 /* Originated in ON or USING clause of a join */
1907 #define EP_Agg       0x000002 /* Contains one or more aggregate functions */
1908 #define EP_Resolved  0x000004 /* IDs have been resolved to COLUMNs */
1909 #define EP_Error     0x000008 /* Expression contains one or more errors */
1910 #define EP_Distinct  0x000010 /* Aggregate function with DISTINCT keyword */
1911 #define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
1912 #define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
1913 #define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
1914 #define EP_Collate   0x000100 /* Tree contains a TK_COLLATE operator */
1915 #define EP_Generic   0x000200 /* Ignore COLLATE or affinity on this tree */
1916 #define EP_IntValue  0x000400 /* Integer value contained in u.iValue */
1917 #define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
1918 #define EP_Skip      0x001000 /* COLLATE, AS, or UNLIKELY */
1919 #define EP_Reduced   0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
1920 #define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
1921 #define EP_Static    0x008000 /* Held in memory not obtained from malloc() */
1922 #define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
1923 #define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
1924 #define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
1925 #define EP_Constant  0x080000 /* Node is a constant */
1926 
1927 /*
1928 ** These macros can be used to test, set, or clear bits in the
1929 ** Expr.flags field.
1930 */
1931 #define ExprHasProperty(E,P)     (((E)->flags&(P))!=0)
1932 #define ExprHasAllProperty(E,P)  (((E)->flags&(P))==(P))
1933 #define ExprSetProperty(E,P)     (E)->flags|=(P)
1934 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
1935 
1936 /* The ExprSetVVAProperty() macro is used for Verification, Validation,
1937 ** and Accreditation only.  It works like ExprSetProperty() during VVA
1938 ** processes but is a no-op for delivery.
1939 */
1940 #ifdef SQLITE_DEBUG
1941 # define ExprSetVVAProperty(E,P)  (E)->flags|=(P)
1942 #else
1943 # define ExprSetVVAProperty(E,P)
1944 #endif
1945 
1946 /*
1947 ** Macros to determine the number of bytes required by a normal Expr
1948 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
1949 ** and an Expr struct with the EP_TokenOnly flag set.
1950 */
1951 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
1952 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
1953 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
1954 
1955 /*
1956 ** Flags passed to the sqlite3ExprDup() function. See the header comment
1957 ** above sqlite3ExprDup() for details.
1958 */
1959 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
1960 
1961 /*
1962 ** A list of expressions.  Each expression may optionally have a
1963 ** name.  An expr/name combination can be used in several ways, such
1964 ** as the list of "expr AS ID" fields following a "SELECT" or in the
1965 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
1966 ** also be used as the argument to a function, in which case the a.zName
1967 ** field is not used.
1968 **
1969 ** By default the Expr.zSpan field holds a human-readable description of
1970 ** the expression that is used in the generation of error messages and
1971 ** column labels.  In this case, Expr.zSpan is typically the text of a
1972 ** column expression as it exists in a SELECT statement.  However, if
1973 ** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
1974 ** of the result column in the form: DATABASE.TABLE.COLUMN.  This later
1975 ** form is used for name resolution with nested FROM clauses.
1976 */
1977 struct ExprList {
1978   int nExpr;             /* Number of expressions on the list */
1979   struct ExprList_item { /* For each expression in the list */
1980     Expr *pExpr;            /* The list of expressions */
1981     char *zName;            /* Token associated with this expression */
1982     char *zSpan;            /* Original text of the expression */
1983     u8 sortOrder;           /* 1 for DESC or 0 for ASC */
1984     unsigned done :1;       /* A flag to indicate when processing is finished */
1985     unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
1986     unsigned reusable :1;   /* Constant expression is reusable */
1987     union {
1988       struct {
1989         u16 iOrderByCol;      /* For ORDER BY, column number in result set */
1990         u16 iAlias;           /* Index into Parse.aAlias[] for zName */
1991       } x;
1992       int iConstExprReg;      /* Register in which Expr value is cached */
1993     } u;
1994   } *a;                  /* Alloc a power of two greater or equal to nExpr */
1995 };
1996 
1997 /*
1998 ** An instance of this structure is used by the parser to record both
1999 ** the parse tree for an expression and the span of input text for an
2000 ** expression.
2001 */
2002 struct ExprSpan {
2003   Expr *pExpr;          /* The expression parse tree */
2004   const char *zStart;   /* First character of input text */
2005   const char *zEnd;     /* One character past the end of input text */
2006 };
2007 
2008 /*
2009 ** An instance of this structure can hold a simple list of identifiers,
2010 ** such as the list "a,b,c" in the following statements:
2011 **
2012 **      INSERT INTO t(a,b,c) VALUES ...;
2013 **      CREATE INDEX idx ON t(a,b,c);
2014 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
2015 **
2016 ** The IdList.a.idx field is used when the IdList represents the list of
2017 ** column names after a table name in an INSERT statement.  In the statement
2018 **
2019 **     INSERT INTO t(a,b,c) ...
2020 **
2021 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
2022 */
2023 struct IdList {
2024   struct IdList_item {
2025     char *zName;      /* Name of the identifier */
2026     int idx;          /* Index in some Table.aCol[] of a column named zName */
2027   } *a;
2028   int nId;         /* Number of identifiers on the list */
2029 };
2030 
2031 /*
2032 ** The bitmask datatype defined below is used for various optimizations.
2033 **
2034 ** Changing this from a 64-bit to a 32-bit type limits the number of
2035 ** tables in a join to 32 instead of 64.  But it also reduces the size
2036 ** of the library by 738 bytes on ix86.
2037 */
2038 typedef u64 Bitmask;
2039 
2040 /*
2041 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
2042 */
2043 #define BMS  ((int)(sizeof(Bitmask)*8))
2044 
2045 /*
2046 ** A bit in a Bitmask
2047 */
2048 #define MASKBIT(n)   (((Bitmask)1)<<(n))
2049 #define MASKBIT32(n) (((unsigned int)1)<<(n))
2050 
2051 /*
2052 ** The following structure describes the FROM clause of a SELECT statement.
2053 ** Each table or subquery in the FROM clause is a separate element of
2054 ** the SrcList.a[] array.
2055 **
2056 ** With the addition of multiple database support, the following structure
2057 ** can also be used to describe a particular table such as the table that
2058 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
2059 ** such a table must be a simple name: ID.  But in SQLite, the table can
2060 ** now be identified by a database name, a dot, then the table name: ID.ID.
2061 **
2062 ** The jointype starts out showing the join type between the current table
2063 ** and the next table on the list.  The parser builds the list this way.
2064 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
2065 ** jointype expresses the join between the table and the previous table.
2066 **
2067 ** In the colUsed field, the high-order bit (bit 63) is set if the table
2068 ** contains more than 63 columns and the 64-th or later column is used.
2069 */
2070 struct SrcList {
2071   int nSrc;        /* Number of tables or subqueries in the FROM clause */
2072   u32 nAlloc;      /* Number of entries allocated in a[] below */
2073   struct SrcList_item {
2074     Schema *pSchema;  /* Schema to which this item is fixed */
2075     char *zDatabase;  /* Name of database holding this table */
2076     char *zName;      /* Name of the table */
2077     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
2078     Table *pTab;      /* An SQL table corresponding to zName */
2079     Select *pSelect;  /* A SELECT statement used in place of a table name */
2080     int addrFillSub;  /* Address of subroutine to manifest a subquery */
2081     int regReturn;    /* Register holding return address of addrFillSub */
2082     int regResult;    /* Registers holding results of a co-routine */
2083     u8 jointype;      /* Type of join between this able and the previous */
2084     unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
2085     unsigned isCorrelated :1;  /* True if sub-query is correlated */
2086     unsigned viaCoroutine :1;  /* Implemented as a co-routine */
2087     unsigned isRecursive :1;   /* True for recursive reference in WITH */
2088 #ifndef SQLITE_OMIT_EXPLAIN
2089     u8 iSelectId;     /* If pSelect!=0, the id of the sub-select in EQP */
2090 #endif
2091     int iCursor;      /* The VDBE cursor number used to access this table */
2092     Expr *pOn;        /* The ON clause of a join */
2093     IdList *pUsing;   /* The USING clause of a join */
2094     Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
2095     char *zIndex;     /* Identifier from "INDEXED BY <zIndex>" clause */
2096     Index *pIndex;    /* Index structure corresponding to zIndex, if any */
2097   } a[1];             /* One entry for each identifier on the list */
2098 };
2099 
2100 /*
2101 ** Permitted values of the SrcList.a.jointype field
2102 */
2103 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
2104 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
2105 #define JT_NATURAL   0x0004    /* True for a "natural" join */
2106 #define JT_LEFT      0x0008    /* Left outer join */
2107 #define JT_RIGHT     0x0010    /* Right outer join */
2108 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
2109 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
2110 
2111 
2112 /*
2113 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
2114 ** and the WhereInfo.wctrlFlags member.
2115 */
2116 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
2117 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
2118 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
2119 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
2120 #define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
2121 #define WHERE_OMIT_OPEN_CLOSE  0x0010 /* Table cursors are already open */
2122 #define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
2123 #define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
2124 #define WHERE_AND_ONLY         0x0080 /* Don't use indices for OR terms */
2125 #define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
2126 #define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
2127 #define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
2128 #define WHERE_SORTBYGROUP      0x0800 /* Support sqlite3WhereIsSorted() */
2129 
2130 /* Allowed return values from sqlite3WhereIsDistinct()
2131 */
2132 #define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
2133 #define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
2134 #define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
2135 #define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
2136 
2137 /*
2138 ** A NameContext defines a context in which to resolve table and column
2139 ** names.  The context consists of a list of tables (the pSrcList) field and
2140 ** a list of named expression (pEList).  The named expression list may
2141 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
2142 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
2143 ** pEList corresponds to the result set of a SELECT and is NULL for
2144 ** other statements.
2145 **
2146 ** NameContexts can be nested.  When resolving names, the inner-most
2147 ** context is searched first.  If no match is found, the next outer
2148 ** context is checked.  If there is still no match, the next context
2149 ** is checked.  This process continues until either a match is found
2150 ** or all contexts are check.  When a match is found, the nRef member of
2151 ** the context containing the match is incremented.
2152 **
2153 ** Each subquery gets a new NameContext.  The pNext field points to the
2154 ** NameContext in the parent query.  Thus the process of scanning the
2155 ** NameContext list corresponds to searching through successively outer
2156 ** subqueries looking for a match.
2157 */
2158 struct NameContext {
2159   Parse *pParse;       /* The parser */
2160   SrcList *pSrcList;   /* One or more tables used to resolve names */
2161   ExprList *pEList;    /* Optional list of result-set columns */
2162   AggInfo *pAggInfo;   /* Information about aggregates at this level */
2163   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
2164   int nRef;            /* Number of names resolved by this context */
2165   int nErr;            /* Number of errors encountered while resolving names */
2166   u8 ncFlags;          /* Zero or more NC_* flags defined below */
2167 };
2168 
2169 /*
2170 ** Allowed values for the NameContext, ncFlags field.
2171 */
2172 #define NC_AllowAgg  0x01    /* Aggregate functions are allowed here */
2173 #define NC_HasAgg    0x02    /* One or more aggregate functions seen */
2174 #define NC_IsCheck   0x04    /* True if resolving names in a CHECK constraint */
2175 #define NC_InAggFunc 0x08    /* True if analyzing arguments to an agg func */
2176 #define NC_PartIdx   0x10    /* True if resolving a partial index WHERE */
2177 
2178 /*
2179 ** An instance of the following structure contains all information
2180 ** needed to generate code for a single SELECT statement.
2181 **
2182 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
2183 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
2184 ** limit and nOffset to the value of the offset (or 0 if there is not
2185 ** offset).  But later on, nLimit and nOffset become the memory locations
2186 ** in the VDBE that record the limit and offset counters.
2187 **
2188 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
2189 ** These addresses must be stored so that we can go back and fill in
2190 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
2191 ** the number of columns in P2 can be computed at the same time
2192 ** as the OP_OpenEphm instruction is coded because not
2193 ** enough information about the compound query is known at that point.
2194 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
2195 ** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
2196 ** sequences for the ORDER BY clause.
2197 */
2198 struct Select {
2199   ExprList *pEList;      /* The fields of the result */
2200   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
2201   u16 selFlags;          /* Various SF_* values */
2202   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
2203   int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
2204   u64 nSelectRow;        /* Estimated number of result rows */
2205   SrcList *pSrc;         /* The FROM clause */
2206   Expr *pWhere;          /* The WHERE clause */
2207   ExprList *pGroupBy;    /* The GROUP BY clause */
2208   Expr *pHaving;         /* The HAVING clause */
2209   ExprList *pOrderBy;    /* The ORDER BY clause */
2210   Select *pPrior;        /* Prior select in a compound select statement */
2211   Select *pNext;         /* Next select to the left in a compound */
2212   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
2213   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
2214   With *pWith;           /* WITH clause attached to this select. Or NULL. */
2215 };
2216 
2217 /*
2218 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
2219 ** "Select Flag".
2220 */
2221 #define SF_Distinct        0x0001  /* Output should be DISTINCT */
2222 #define SF_Resolved        0x0002  /* Identifiers have been resolved */
2223 #define SF_Aggregate       0x0004  /* Contains aggregate functions */
2224 #define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
2225 #define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
2226 #define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
2227                     /*     0x0040  NOT USED */
2228 #define SF_Values          0x0080  /* Synthesized from VALUES clause */
2229                     /*     0x0100  NOT USED */
2230 #define SF_NestedFrom      0x0200  /* Part of a parenthesized FROM clause */
2231 #define SF_MaybeConvert    0x0400  /* Need convertCompoundSelectToSubquery() */
2232 #define SF_Recursive       0x0800  /* The recursive part of a recursive CTE */
2233 #define SF_Compound        0x1000  /* Part of a compound query */
2234 
2235 
2236 /*
2237 ** The results of a SELECT can be distributed in several ways, as defined
2238 ** by one of the following macros.  The "SRT" prefix means "SELECT Result
2239 ** Type".
2240 **
2241 **     SRT_Union       Store results as a key in a temporary index
2242 **                     identified by pDest->iSDParm.
2243 **
2244 **     SRT_Except      Remove results from the temporary index pDest->iSDParm.
2245 **
2246 **     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
2247 **                     set is not empty.
2248 **
2249 **     SRT_Discard     Throw the results away.  This is used by SELECT
2250 **                     statements within triggers whose only purpose is
2251 **                     the side-effects of functions.
2252 **
2253 ** All of the above are free to ignore their ORDER BY clause. Those that
2254 ** follow must honor the ORDER BY clause.
2255 **
2256 **     SRT_Output      Generate a row of output (using the OP_ResultRow
2257 **                     opcode) for each row in the result set.
2258 **
2259 **     SRT_Mem         Only valid if the result is a single column.
2260 **                     Store the first column of the first result row
2261 **                     in register pDest->iSDParm then abandon the rest
2262 **                     of the query.  This destination implies "LIMIT 1".
2263 **
2264 **     SRT_Set         The result must be a single column.  Store each
2265 **                     row of result as the key in table pDest->iSDParm.
2266 **                     Apply the affinity pDest->affSdst before storing
2267 **                     results.  Used to implement "IN (SELECT ...)".
2268 **
2269 **     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
2270 **                     the result there. The cursor is left open after
2271 **                     returning.  This is like SRT_Table except that
2272 **                     this destination uses OP_OpenEphemeral to create
2273 **                     the table first.
2274 **
2275 **     SRT_Coroutine   Generate a co-routine that returns a new row of
2276 **                     results each time it is invoked.  The entry point
2277 **                     of the co-routine is stored in register pDest->iSDParm
2278 **                     and the result row is stored in pDest->nDest registers
2279 **                     starting with pDest->iSdst.
2280 **
2281 **     SRT_Table       Store results in temporary table pDest->iSDParm.
2282 **     SRT_Fifo        This is like SRT_EphemTab except that the table
2283 **                     is assumed to already be open.  SRT_Fifo has
2284 **                     the additional property of being able to ignore
2285 **                     the ORDER BY clause.
2286 **
2287 **     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
2288 **                     But also use temporary table pDest->iSDParm+1 as
2289 **                     a record of all prior results and ignore any duplicate
2290 **                     rows.  Name means:  "Distinct Fifo".
2291 **
2292 **     SRT_Queue       Store results in priority queue pDest->iSDParm (really
2293 **                     an index).  Append a sequence number so that all entries
2294 **                     are distinct.
2295 **
2296 **     SRT_DistQueue   Store results in priority queue pDest->iSDParm only if
2297 **                     the same record has never been stored before.  The
2298 **                     index at pDest->iSDParm+1 hold all prior stores.
2299 */
2300 #define SRT_Union        1  /* Store result as keys in an index */
2301 #define SRT_Except       2  /* Remove result from a UNION index */
2302 #define SRT_Exists       3  /* Store 1 if the result is not empty */
2303 #define SRT_Discard      4  /* Do not save the results anywhere */
2304 #define SRT_Fifo         5  /* Store result as data with an automatic rowid */
2305 #define SRT_DistFifo     6  /* Like SRT_Fifo, but unique results only */
2306 #define SRT_Queue        7  /* Store result in an queue */
2307 #define SRT_DistQueue    8  /* Like SRT_Queue, but unique results only */
2308 
2309 /* The ORDER BY clause is ignored for all of the above */
2310 #define IgnorableOrderby(X) ((X->eDest)<=SRT_DistQueue)
2311 
2312 #define SRT_Output       9  /* Output each row of result */
2313 #define SRT_Mem         10  /* Store result in a memory cell */
2314 #define SRT_Set         11  /* Store results as keys in an index */
2315 #define SRT_EphemTab    12  /* Create transient tab and store like SRT_Table */
2316 #define SRT_Coroutine   13  /* Generate a single row of result */
2317 #define SRT_Table       14  /* Store result as data with an automatic rowid */
2318 
2319 /*
2320 ** An instance of this object describes where to put of the results of
2321 ** a SELECT statement.
2322 */
2323 struct SelectDest {
2324   u8 eDest;            /* How to dispose of the results.  On of SRT_* above. */
2325   char affSdst;        /* Affinity used when eDest==SRT_Set */
2326   int iSDParm;         /* A parameter used by the eDest disposal method */
2327   int iSdst;           /* Base register where results are written */
2328   int nSdst;           /* Number of registers allocated */
2329   ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
2330 };
2331 
2332 /*
2333 ** During code generation of statements that do inserts into AUTOINCREMENT
2334 ** tables, the following information is attached to the Table.u.autoInc.p
2335 ** pointer of each autoincrement table to record some side information that
2336 ** the code generator needs.  We have to keep per-table autoincrement
2337 ** information in case inserts are down within triggers.  Triggers do not
2338 ** normally coordinate their activities, but we do need to coordinate the
2339 ** loading and saving of autoincrement information.
2340 */
2341 struct AutoincInfo {
2342   AutoincInfo *pNext;   /* Next info block in a list of them all */
2343   Table *pTab;          /* Table this info block refers to */
2344   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
2345   int regCtr;           /* Memory register holding the rowid counter */
2346 };
2347 
2348 /*
2349 ** Size of the column cache
2350 */
2351 #ifndef SQLITE_N_COLCACHE
2352 # define SQLITE_N_COLCACHE 10
2353 #endif
2354 
2355 /*
2356 ** At least one instance of the following structure is created for each
2357 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
2358 ** statement. All such objects are stored in the linked list headed at
2359 ** Parse.pTriggerPrg and deleted once statement compilation has been
2360 ** completed.
2361 **
2362 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
2363 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
2364 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
2365 ** The Parse.pTriggerPrg list never contains two entries with the same
2366 ** values for both pTrigger and orconf.
2367 **
2368 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
2369 ** accessed (or set to 0 for triggers fired as a result of INSERT
2370 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
2371 ** a mask of new.* columns used by the program.
2372 */
2373 struct TriggerPrg {
2374   Trigger *pTrigger;      /* Trigger this program was coded from */
2375   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
2376   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
2377   int orconf;             /* Default ON CONFLICT policy */
2378   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
2379 };
2380 
2381 /*
2382 ** The yDbMask datatype for the bitmask of all attached databases.
2383 */
2384 #if SQLITE_MAX_ATTACHED>30
2385   typedef sqlite3_uint64 yDbMask;
2386 #else
2387   typedef unsigned int yDbMask;
2388 #endif
2389 
2390 /*
2391 ** An SQL parser context.  A copy of this structure is passed through
2392 ** the parser and down into all the parser action routine in order to
2393 ** carry around information that is global to the entire parse.
2394 **
2395 ** The structure is divided into two parts.  When the parser and code
2396 ** generate call themselves recursively, the first part of the structure
2397 ** is constant but the second part is reset at the beginning and end of
2398 ** each recursion.
2399 **
2400 ** The nTableLock and aTableLock variables are only used if the shared-cache
2401 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
2402 ** used to store the set of table-locks required by the statement being
2403 ** compiled. Function sqlite3TableLock() is used to add entries to the
2404 ** list.
2405 */
2406 struct Parse {
2407   sqlite3 *db;         /* The main database structure */
2408   char *zErrMsg;       /* An error message */
2409   Vdbe *pVdbe;         /* An engine for executing database bytecode */
2410   int rc;              /* Return code from execution */
2411   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
2412   u8 checkSchema;      /* Causes schema cookie check after an error */
2413   u8 nested;           /* Number of nested calls to the parser/code generator */
2414   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
2415   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
2416   u8 mayAbort;         /* True if statement may throw an ABORT exception */
2417   u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
2418   u8 okConstFactor;    /* OK to factor out constants */
2419   int aTempReg[8];     /* Holding area for temporary registers */
2420   int nRangeReg;       /* Size of the temporary register block */
2421   int iRangeReg;       /* First register in temporary register block */
2422   int nErr;            /* Number of errors seen */
2423   int nTab;            /* Number of previously allocated VDBE cursors */
2424   int nMem;            /* Number of memory cells used so far */
2425   int nSet;            /* Number of sets used so far */
2426   int nOnce;           /* Number of OP_Once instructions so far */
2427   int nOpAlloc;        /* Number of slots allocated for Vdbe.aOp[] */
2428   int iFixedOp;        /* Never back out opcodes iFixedOp-1 or earlier */
2429   int ckBase;          /* Base register of data during check constraints */
2430   int iPartIdxTab;     /* Table corresponding to a partial index */
2431   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
2432   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
2433   int nLabel;          /* Number of labels used */
2434   int *aLabel;         /* Space to hold the labels */
2435   struct yColCache {
2436     int iTable;           /* Table cursor number */
2437     i16 iColumn;          /* Table column number */
2438     u8 tempReg;           /* iReg is a temp register that needs to be freed */
2439     int iLevel;           /* Nesting level */
2440     int iReg;             /* Reg with value of this column. 0 means none. */
2441     int lru;              /* Least recently used entry has the smallest value */
2442   } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
2443   ExprList *pConstExpr;/* Constant expressions */
2444   Token constraintName;/* Name of the constraint currently being parsed */
2445   yDbMask writeMask;   /* Start a write transaction on these databases */
2446   yDbMask cookieMask;  /* Bitmask of schema verified databases */
2447   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
2448   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
2449   int regRoot;         /* Register holding root page number for new objects */
2450   int nMaxArg;         /* Max args passed to user function by sub-program */
2451 #ifndef SQLITE_OMIT_SHARED_CACHE
2452   int nTableLock;        /* Number of locks in aTableLock */
2453   TableLock *aTableLock; /* Required table locks for shared-cache mode */
2454 #endif
2455   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
2456 
2457   /* Information used while coding trigger programs. */
2458   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
2459   Table *pTriggerTab;  /* Table triggers are being coded for */
2460   int addrCrTab;       /* Address of OP_CreateTable opcode on CREATE TABLE */
2461   int addrSkipPK;      /* Address of instruction to skip PRIMARY KEY index */
2462   u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
2463   u32 oldmask;         /* Mask of old.* columns referenced */
2464   u32 newmask;         /* Mask of new.* columns referenced */
2465   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
2466   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
2467   u8 disableTriggers;  /* True to disable triggers */
2468 
2469   /************************************************************************
2470   ** Above is constant between recursions.  Below is reset before and after
2471   ** each recursion.  The boundary between these two regions is determined
2472   ** using offsetof(Parse,nVar) so the nVar field must be the first field
2473   ** in the recursive region.
2474   ************************************************************************/
2475 
2476   int nVar;                 /* Number of '?' variables seen in the SQL so far */
2477   int nzVar;                /* Number of available slots in azVar[] */
2478   u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
2479   u8 bFreeWith;             /* True if pWith should be freed with parser */
2480   u8 explain;               /* True if the EXPLAIN flag is found on the query */
2481 #ifndef SQLITE_OMIT_VIRTUALTABLE
2482   u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
2483   int nVtabLock;            /* Number of virtual tables to lock */
2484 #endif
2485   int nAlias;               /* Number of aliased result set columns */
2486   int nHeight;              /* Expression tree height of current sub-select */
2487 #ifndef SQLITE_OMIT_EXPLAIN
2488   int iSelectId;            /* ID of current select for EXPLAIN output */
2489   int iNextSelectId;        /* Next available select ID for EXPLAIN output */
2490 #endif
2491   char **azVar;             /* Pointers to names of parameters */
2492   Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
2493   const char *zTail;        /* All SQL text past the last semicolon parsed */
2494   Table *pNewTable;         /* A table being constructed by CREATE TABLE */
2495   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
2496   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
2497   Token sNameToken;         /* Token with unqualified schema object name */
2498   Token sLastToken;         /* The last token parsed */
2499 #ifndef SQLITE_OMIT_VIRTUALTABLE
2500   Token sArg;               /* Complete text of a module argument */
2501   Table **apVtabLock;       /* Pointer to virtual tables needing locking */
2502 #endif
2503   Table *pZombieTab;        /* List of Table objects to delete after code gen */
2504   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
2505   With *pWith;              /* Current WITH clause, or NULL */
2506 };
2507 
2508 /*
2509 ** Return true if currently inside an sqlite3_declare_vtab() call.
2510 */
2511 #ifdef SQLITE_OMIT_VIRTUALTABLE
2512   #define IN_DECLARE_VTAB 0
2513 #else
2514   #define IN_DECLARE_VTAB (pParse->declareVtab)
2515 #endif
2516 
2517 /*
2518 ** An instance of the following structure can be declared on a stack and used
2519 ** to save the Parse.zAuthContext value so that it can be restored later.
2520 */
2521 struct AuthContext {
2522   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
2523   Parse *pParse;              /* The Parse structure */
2524 };
2525 
2526 /*
2527 ** Bitfield flags for P5 value in various opcodes.
2528 */
2529 #define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
2530 #define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
2531 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
2532 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
2533 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
2534 #define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
2535 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
2536 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
2537 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
2538 #define OPFLAG_P2ISREG       0x02    /* P2 to OP_Open** is a register number */
2539 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
2540 
2541 /*
2542  * Each trigger present in the database schema is stored as an instance of
2543  * struct Trigger.
2544  *
2545  * Pointers to instances of struct Trigger are stored in two ways.
2546  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
2547  *    database). This allows Trigger structures to be retrieved by name.
2548  * 2. All triggers associated with a single table form a linked list, using the
2549  *    pNext member of struct Trigger. A pointer to the first element of the
2550  *    linked list is stored as the "pTrigger" member of the associated
2551  *    struct Table.
2552  *
2553  * The "step_list" member points to the first element of a linked list
2554  * containing the SQL statements specified as the trigger program.
2555  */
2556 struct Trigger {
2557   char *zName;            /* The name of the trigger                        */
2558   char *table;            /* The table or view to which the trigger applies */
2559   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
2560   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
2561   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
2562   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
2563                              the <column-list> is stored here */
2564   Schema *pSchema;        /* Schema containing the trigger */
2565   Schema *pTabSchema;     /* Schema containing the table */
2566   TriggerStep *step_list; /* Link list of trigger program steps             */
2567   Trigger *pNext;         /* Next trigger associated with the table */
2568 };
2569 
2570 /*
2571 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
2572 ** determine which.
2573 **
2574 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
2575 ** In that cases, the constants below can be ORed together.
2576 */
2577 #define TRIGGER_BEFORE  1
2578 #define TRIGGER_AFTER   2
2579 
2580 /*
2581  * An instance of struct TriggerStep is used to store a single SQL statement
2582  * that is a part of a trigger-program.
2583  *
2584  * Instances of struct TriggerStep are stored in a singly linked list (linked
2585  * using the "pNext" member) referenced by the "step_list" member of the
2586  * associated struct Trigger instance. The first element of the linked list is
2587  * the first step of the trigger-program.
2588  *
2589  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
2590  * "SELECT" statement. The meanings of the other members is determined by the
2591  * value of "op" as follows:
2592  *
2593  * (op == TK_INSERT)
2594  * orconf    -> stores the ON CONFLICT algorithm
2595  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
2596  *              this stores a pointer to the SELECT statement. Otherwise NULL.
2597  * target    -> A token holding the quoted name of the table to insert into.
2598  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
2599  *              this stores values to be inserted. Otherwise NULL.
2600  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
2601  *              statement, then this stores the column-names to be
2602  *              inserted into.
2603  *
2604  * (op == TK_DELETE)
2605  * target    -> A token holding the quoted name of the table to delete from.
2606  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
2607  *              Otherwise NULL.
2608  *
2609  * (op == TK_UPDATE)
2610  * target    -> A token holding the quoted name of the table to update rows of.
2611  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
2612  *              Otherwise NULL.
2613  * pExprList -> A list of the columns to update and the expressions to update
2614  *              them to. See sqlite3Update() documentation of "pChanges"
2615  *              argument.
2616  *
2617  */
2618 struct TriggerStep {
2619   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
2620   u8 orconf;           /* OE_Rollback etc. */
2621   Trigger *pTrig;      /* The trigger that this step is a part of */
2622   Select *pSelect;     /* SELECT statment or RHS of INSERT INTO .. SELECT ... */
2623   Token target;        /* Target table for DELETE, UPDATE, INSERT */
2624   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
2625   ExprList *pExprList; /* SET clause for UPDATE. */
2626   IdList *pIdList;     /* Column names for INSERT */
2627   TriggerStep *pNext;  /* Next in the link-list */
2628   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
2629 };
2630 
2631 /*
2632 ** The following structure contains information used by the sqliteFix...
2633 ** routines as they walk the parse tree to make database references
2634 ** explicit.
2635 */
2636 typedef struct DbFixer DbFixer;
2637 struct DbFixer {
2638   Parse *pParse;      /* The parsing context.  Error messages written here */
2639   Schema *pSchema;    /* Fix items to this schema */
2640   int bVarOnly;       /* Check for variable references only */
2641   const char *zDb;    /* Make sure all objects are contained in this database */
2642   const char *zType;  /* Type of the container - used for error messages */
2643   const Token *pName; /* Name of the container - used for error messages */
2644 };
2645 
2646 /*
2647 ** An objected used to accumulate the text of a string where we
2648 ** do not necessarily know how big the string will be in the end.
2649 */
2650 struct StrAccum {
2651   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
2652   char *zBase;         /* A base allocation.  Not from malloc. */
2653   char *zText;         /* The string collected so far */
2654   int  nChar;          /* Length of the string so far */
2655   int  nAlloc;         /* Amount of space allocated in zText */
2656   int  mxAlloc;        /* Maximum allowed string length */
2657   u8   useMalloc;      /* 0: none,  1: sqlite3DbMalloc,  2: sqlite3_malloc */
2658   u8   accError;       /* STRACCUM_NOMEM or STRACCUM_TOOBIG */
2659 };
2660 #define STRACCUM_NOMEM   1
2661 #define STRACCUM_TOOBIG  2
2662 
2663 /*
2664 ** A pointer to this structure is used to communicate information
2665 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
2666 */
2667 typedef struct {
2668   sqlite3 *db;        /* The database being initialized */
2669   char **pzErrMsg;    /* Error message stored here */
2670   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
2671   int rc;             /* Result code stored here */
2672 } InitData;
2673 
2674 /*
2675 ** Structure containing global configuration data for the SQLite library.
2676 **
2677 ** This structure also contains some state information.
2678 */
2679 struct Sqlite3Config {
2680   int bMemstat;                     /* True to enable memory status */
2681   int bCoreMutex;                   /* True to enable core mutexing */
2682   int bFullMutex;                   /* True to enable full mutexing */
2683   int bOpenUri;                     /* True to interpret filenames as URIs */
2684   int bUseCis;                      /* Use covering indices for full-scans */
2685   int mxStrlen;                     /* Maximum string length */
2686   int neverCorrupt;                 /* Database is always well-formed */
2687   int szLookaside;                  /* Default lookaside buffer size */
2688   int nLookaside;                   /* Default lookaside buffer count */
2689   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
2690   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
2691   sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
2692   void *pHeap;                      /* Heap storage space */
2693   int nHeap;                        /* Size of pHeap[] */
2694   int mnReq, mxReq;                 /* Min and max heap requests sizes */
2695   sqlite3_int64 szMmap;             /* mmap() space per open file */
2696   sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
2697   void *pScratch;                   /* Scratch memory */
2698   int szScratch;                    /* Size of each scratch buffer */
2699   int nScratch;                     /* Number of scratch buffers */
2700   void *pPage;                      /* Page cache memory */
2701   int szPage;                       /* Size of each page in pPage[] */
2702   int nPage;                        /* Number of pages in pPage[] */
2703   int mxParserStack;                /* maximum depth of the parser stack */
2704   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
2705   /* The above might be initialized to non-zero.  The following need to always
2706   ** initially be zero, however. */
2707   int isInit;                       /* True after initialization has finished */
2708   int inProgress;                   /* True while initialization in progress */
2709   int isMutexInit;                  /* True after mutexes are initialized */
2710   int isMallocInit;                 /* True after malloc is initialized */
2711   int isPCacheInit;                 /* True after malloc is initialized */
2712   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
2713   int nRefInitMutex;                /* Number of users of pInitMutex */
2714   void (*xLog)(void*,int,const char*); /* Function for logging */
2715   void *pLogArg;                       /* First argument to xLog() */
2716   int bLocaltimeFault;              /* True to fail localtime() calls */
2717 #ifdef SQLITE_ENABLE_SQLLOG
2718   void(*xSqllog)(void*,sqlite3*,const char*, int);
2719   void *pSqllogArg;
2720 #endif
2721 #ifdef SQLITE_VDBE_COVERAGE
2722   /* The following callback (if not NULL) is invoked on every VDBE branch
2723   ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
2724   */
2725   void (*xVdbeBranch)(void*,int iSrcLine,u8 eThis,u8 eMx);  /* Callback */
2726   void *pVdbeBranchArg;                                     /* 1st argument */
2727 #endif
2728 };
2729 
2730 /*
2731 ** This macro is used inside of assert() statements to indicate that
2732 ** the assert is only valid on a well-formed database.  Instead of:
2733 **
2734 **     assert( X );
2735 **
2736 ** One writes:
2737 **
2738 **     assert( X || CORRUPT_DB );
2739 **
2740 ** CORRUPT_DB is true during normal operation.  CORRUPT_DB does not indicate
2741 ** that the database is definitely corrupt, only that it might be corrupt.
2742 ** For most test cases, CORRUPT_DB is set to false using a special
2743 ** sqlite3_test_control().  This enables assert() statements to prove
2744 ** things that are always true for well-formed databases.
2745 */
2746 #define CORRUPT_DB  (sqlite3Config.neverCorrupt==0)
2747 
2748 /*
2749 ** Context pointer passed down through the tree-walk.
2750 */
2751 struct Walker {
2752   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
2753   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
2754   void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
2755   Parse *pParse;                            /* Parser context.  */
2756   int walkerDepth;                          /* Number of subqueries */
2757   union {                                   /* Extra data for callback */
2758     NameContext *pNC;                          /* Naming context */
2759     int i;                                     /* Integer value */
2760     SrcList *pSrcList;                         /* FROM clause */
2761     struct SrcCount *pSrcCount;                /* Counting column references */
2762   } u;
2763 };
2764 
2765 /* Forward declarations */
2766 int sqlite3WalkExpr(Walker*, Expr*);
2767 int sqlite3WalkExprList(Walker*, ExprList*);
2768 int sqlite3WalkSelect(Walker*, Select*);
2769 int sqlite3WalkSelectExpr(Walker*, Select*);
2770 int sqlite3WalkSelectFrom(Walker*, Select*);
2771 
2772 /*
2773 ** Return code from the parse-tree walking primitives and their
2774 ** callbacks.
2775 */
2776 #define WRC_Continue    0   /* Continue down into children */
2777 #define WRC_Prune       1   /* Omit children but continue walking siblings */
2778 #define WRC_Abort       2   /* Abandon the tree walk */
2779 
2780 /*
2781 ** An instance of this structure represents a set of one or more CTEs
2782 ** (common table expressions) created by a single WITH clause.
2783 */
2784 struct With {
2785   int nCte;                       /* Number of CTEs in the WITH clause */
2786   With *pOuter;                   /* Containing WITH clause, or NULL */
2787   struct Cte {                    /* For each CTE in the WITH clause.... */
2788     char *zName;                    /* Name of this CTE */
2789     ExprList *pCols;                /* List of explicit column names, or NULL */
2790     Select *pSelect;                /* The definition of this CTE */
2791     const char *zErr;               /* Error message for circular references */
2792   } a[1];
2793 };
2794 
2795 /*
2796 ** Assuming zIn points to the first byte of a UTF-8 character,
2797 ** advance zIn to point to the first byte of the next UTF-8 character.
2798 */
2799 #define SQLITE_SKIP_UTF8(zIn) {                        \
2800   if( (*(zIn++))>=0xc0 ){                              \
2801     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
2802   }                                                    \
2803 }
2804 
2805 /*
2806 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
2807 ** the same name but without the _BKPT suffix.  These macros invoke
2808 ** routines that report the line-number on which the error originated
2809 ** using sqlite3_log().  The routines also provide a convenient place
2810 ** to set a debugger breakpoint.
2811 */
2812 int sqlite3CorruptError(int);
2813 int sqlite3MisuseError(int);
2814 int sqlite3CantopenError(int);
2815 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
2816 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
2817 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
2818 
2819 
2820 /*
2821 ** FTS4 is really an extension for FTS3.  It is enabled using the
2822 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also all
2823 ** the SQLITE_ENABLE_FTS4 macro to serve as an alisse for SQLITE_ENABLE_FTS3.
2824 */
2825 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
2826 # define SQLITE_ENABLE_FTS3
2827 #endif
2828 
2829 /*
2830 ** The ctype.h header is needed for non-ASCII systems.  It is also
2831 ** needed by FTS3 when FTS3 is included in the amalgamation.
2832 */
2833 #if !defined(SQLITE_ASCII) || \
2834     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
2835 # include <ctype.h>
2836 #endif
2837 
2838 /*
2839 ** The following macros mimic the standard library functions toupper(),
2840 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
2841 ** sqlite versions only work for ASCII characters, regardless of locale.
2842 */
2843 #ifdef SQLITE_ASCII
2844 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
2845 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
2846 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
2847 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
2848 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
2849 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
2850 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
2851 #else
2852 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
2853 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
2854 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
2855 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
2856 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
2857 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
2858 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
2859 #endif
2860 
2861 /*
2862 ** Internal function prototypes
2863 */
2864 #define sqlite3StrICmp sqlite3_stricmp
2865 int sqlite3Strlen30(const char*);
2866 #define sqlite3StrNICmp sqlite3_strnicmp
2867 
2868 int sqlite3MallocInit(void);
2869 void sqlite3MallocEnd(void);
2870 void *sqlite3Malloc(int);
2871 void *sqlite3MallocZero(int);
2872 void *sqlite3DbMallocZero(sqlite3*, int);
2873 void *sqlite3DbMallocRaw(sqlite3*, int);
2874 char *sqlite3DbStrDup(sqlite3*,const char*);
2875 char *sqlite3DbStrNDup(sqlite3*,const char*, int);
2876 void *sqlite3Realloc(void*, int);
2877 void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
2878 void *sqlite3DbRealloc(sqlite3 *, void *, int);
2879 void sqlite3DbFree(sqlite3*, void*);
2880 int sqlite3MallocSize(void*);
2881 int sqlite3DbMallocSize(sqlite3*, void*);
2882 void *sqlite3ScratchMalloc(int);
2883 void sqlite3ScratchFree(void*);
2884 void *sqlite3PageMalloc(int);
2885 void sqlite3PageFree(void*);
2886 void sqlite3MemSetDefault(void);
2887 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
2888 int sqlite3HeapNearlyFull(void);
2889 
2890 /*
2891 ** On systems with ample stack space and that support alloca(), make
2892 ** use of alloca() to obtain space for large automatic objects.  By default,
2893 ** obtain space from malloc().
2894 **
2895 ** The alloca() routine never returns NULL.  This will cause code paths
2896 ** that deal with sqlite3StackAlloc() failures to be unreachable.
2897 */
2898 #ifdef SQLITE_USE_ALLOCA
2899 # define sqlite3StackAllocRaw(D,N)   alloca(N)
2900 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
2901 # define sqlite3StackFree(D,P)
2902 #else
2903 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
2904 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
2905 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
2906 #endif
2907 
2908 #ifdef SQLITE_ENABLE_MEMSYS3
2909 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
2910 #endif
2911 #ifdef SQLITE_ENABLE_MEMSYS5
2912 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
2913 #endif
2914 
2915 
2916 #ifndef SQLITE_MUTEX_OMIT
2917   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
2918   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
2919   sqlite3_mutex *sqlite3MutexAlloc(int);
2920   int sqlite3MutexInit(void);
2921   int sqlite3MutexEnd(void);
2922 #endif
2923 
2924 int sqlite3StatusValue(int);
2925 void sqlite3StatusAdd(int, int);
2926 void sqlite3StatusSet(int, int);
2927 
2928 #ifndef SQLITE_OMIT_FLOATING_POINT
2929   int sqlite3IsNaN(double);
2930 #else
2931 # define sqlite3IsNaN(X)  0
2932 #endif
2933 
2934 /*
2935 ** An instance of the following structure holds information about SQL
2936 ** functions arguments that are the parameters to the printf() function.
2937 */
2938 struct PrintfArguments {
2939   int nArg;                /* Total number of arguments */
2940   int nUsed;               /* Number of arguments used so far */
2941   sqlite3_value **apArg;   /* The argument values */
2942 };
2943 
2944 #define SQLITE_PRINTF_INTERNAL 0x01
2945 #define SQLITE_PRINTF_SQLFUNC  0x02
2946 void sqlite3VXPrintf(StrAccum*, u32, const char*, va_list);
2947 void sqlite3XPrintf(StrAccum*, u32, const char*, ...);
2948 char *sqlite3MPrintf(sqlite3*,const char*, ...);
2949 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
2950 char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
2951 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
2952   void sqlite3DebugPrintf(const char*, ...);
2953 #endif
2954 #if defined(SQLITE_TEST)
2955   void *sqlite3TestTextToPtr(const char*);
2956 #endif
2957 
2958 /* Output formatting for SQLITE_TESTCTRL_EXPLAIN */
2959 #if defined(SQLITE_ENABLE_TREE_EXPLAIN)
2960   void sqlite3ExplainBegin(Vdbe*);
2961   void sqlite3ExplainPrintf(Vdbe*, const char*, ...);
2962   void sqlite3ExplainNL(Vdbe*);
2963   void sqlite3ExplainPush(Vdbe*);
2964   void sqlite3ExplainPop(Vdbe*);
2965   void sqlite3ExplainFinish(Vdbe*);
2966   void sqlite3ExplainSelect(Vdbe*, Select*);
2967   void sqlite3ExplainExpr(Vdbe*, Expr*);
2968   void sqlite3ExplainExprList(Vdbe*, ExprList*);
2969   const char *sqlite3VdbeExplanation(Vdbe*);
2970 #else
2971 # define sqlite3ExplainBegin(X)
2972 # define sqlite3ExplainSelect(A,B)
2973 # define sqlite3ExplainExpr(A,B)
2974 # define sqlite3ExplainExprList(A,B)
2975 # define sqlite3ExplainFinish(X)
2976 # define sqlite3VdbeExplanation(X) 0
2977 #endif
2978 
2979 
2980 void sqlite3SetString(char **, sqlite3*, const char*, ...);
2981 void sqlite3ErrorMsg(Parse*, const char*, ...);
2982 int sqlite3Dequote(char*);
2983 int sqlite3KeywordCode(const unsigned char*, int);
2984 int sqlite3RunParser(Parse*, const char*, char **);
2985 void sqlite3FinishCoding(Parse*);
2986 int sqlite3GetTempReg(Parse*);
2987 void sqlite3ReleaseTempReg(Parse*,int);
2988 int sqlite3GetTempRange(Parse*,int);
2989 void sqlite3ReleaseTempRange(Parse*,int,int);
2990 void sqlite3ClearTempRegCache(Parse*);
2991 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
2992 Expr *sqlite3Expr(sqlite3*,int,const char*);
2993 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
2994 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
2995 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
2996 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
2997 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
2998 void sqlite3ExprDelete(sqlite3*, Expr*);
2999 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
3000 void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
3001 void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
3002 void sqlite3ExprListDelete(sqlite3*, ExprList*);
3003 int sqlite3Init(sqlite3*, char**);
3004 int sqlite3InitCallback(void*, int, char**, char**);
3005 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
3006 void sqlite3ResetAllSchemasOfConnection(sqlite3*);
3007 void sqlite3ResetOneSchema(sqlite3*,int);
3008 void sqlite3CollapseDatabaseArray(sqlite3*);
3009 void sqlite3BeginParse(Parse*,int);
3010 void sqlite3CommitInternalChanges(sqlite3*);
3011 Table *sqlite3ResultSetOfSelect(Parse*,Select*);
3012 void sqlite3OpenMasterTable(Parse *, int);
3013 Index *sqlite3PrimaryKeyIndex(Table*);
3014 i16 sqlite3ColumnOfIndex(Index*, i16);
3015 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
3016 void sqlite3AddColumn(Parse*,Token*);
3017 void sqlite3AddNotNull(Parse*, int);
3018 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
3019 void sqlite3AddCheckConstraint(Parse*, Expr*);
3020 void sqlite3AddColumnType(Parse*,Token*);
3021 void sqlite3AddDefaultValue(Parse*,ExprSpan*);
3022 void sqlite3AddCollateType(Parse*, Token*);
3023 void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
3024 int sqlite3ParseUri(const char*,const char*,unsigned int*,
3025                     sqlite3_vfs**,char**,char **);
3026 Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
3027 int sqlite3CodeOnce(Parse *);
3028 
3029 Bitvec *sqlite3BitvecCreate(u32);
3030 int sqlite3BitvecTest(Bitvec*, u32);
3031 int sqlite3BitvecSet(Bitvec*, u32);
3032 void sqlite3BitvecClear(Bitvec*, u32, void*);
3033 void sqlite3BitvecDestroy(Bitvec*);
3034 u32 sqlite3BitvecSize(Bitvec*);
3035 int sqlite3BitvecBuiltinTest(int,int*);
3036 
3037 RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
3038 void sqlite3RowSetClear(RowSet*);
3039 void sqlite3RowSetInsert(RowSet*, i64);
3040 int sqlite3RowSetTest(RowSet*, int iBatch, i64);
3041 int sqlite3RowSetNext(RowSet*, i64*);
3042 
3043 void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
3044 
3045 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
3046   int sqlite3ViewGetColumnNames(Parse*,Table*);
3047 #else
3048 # define sqlite3ViewGetColumnNames(A,B) 0
3049 #endif
3050 
3051 void sqlite3DropTable(Parse*, SrcList*, int, int);
3052 void sqlite3CodeDropTable(Parse*, Table*, int, int);
3053 void sqlite3DeleteTable(sqlite3*, Table*);
3054 #ifndef SQLITE_OMIT_AUTOINCREMENT
3055   void sqlite3AutoincrementBegin(Parse *pParse);
3056   void sqlite3AutoincrementEnd(Parse *pParse);
3057 #else
3058 # define sqlite3AutoincrementBegin(X)
3059 # define sqlite3AutoincrementEnd(X)
3060 #endif
3061 void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int);
3062 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
3063 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
3064 int sqlite3IdListIndex(IdList*,const char*);
3065 SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
3066 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
3067 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
3068                                       Token*, Select*, Expr*, IdList*);
3069 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
3070 int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
3071 void sqlite3SrcListShiftJoinType(SrcList*);
3072 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
3073 void sqlite3IdListDelete(sqlite3*, IdList*);
3074 void sqlite3SrcListDelete(sqlite3*, SrcList*);
3075 Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
3076 Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
3077                           Expr*, int, int);
3078 void sqlite3DropIndex(Parse*, SrcList*, int);
3079 int sqlite3Select(Parse*, Select*, SelectDest*);
3080 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
3081                          Expr*,ExprList*,u16,Expr*,Expr*);
3082 void sqlite3SelectDelete(sqlite3*, Select*);
3083 Table *sqlite3SrcListLookup(Parse*, SrcList*);
3084 int sqlite3IsReadOnly(Parse*, Table*, int);
3085 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
3086 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
3087 Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,Expr*,char*);
3088 #endif
3089 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
3090 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
3091 WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
3092 void sqlite3WhereEnd(WhereInfo*);
3093 u64 sqlite3WhereOutputRowCount(WhereInfo*);
3094 int sqlite3WhereIsDistinct(WhereInfo*);
3095 int sqlite3WhereIsOrdered(WhereInfo*);
3096 int sqlite3WhereIsSorted(WhereInfo*);
3097 int sqlite3WhereContinueLabel(WhereInfo*);
3098 int sqlite3WhereBreakLabel(WhereInfo*);
3099 int sqlite3WhereOkOnePass(WhereInfo*, int*);
3100 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
3101 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
3102 void sqlite3ExprCodeMove(Parse*, int, int, int);
3103 void sqlite3ExprCacheStore(Parse*, int, int, int);
3104 void sqlite3ExprCachePush(Parse*);
3105 void sqlite3ExprCachePop(Parse*);
3106 void sqlite3ExprCacheRemove(Parse*, int, int);
3107 void sqlite3ExprCacheClear(Parse*);
3108 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
3109 void sqlite3ExprCode(Parse*, Expr*, int);
3110 void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
3111 void sqlite3ExprCodeAtInit(Parse*, Expr*, int, u8);
3112 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
3113 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
3114 void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
3115 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, u8);
3116 #define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
3117 #define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
3118 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
3119 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
3120 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
3121 Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
3122 Table *sqlite3LocateTableItem(Parse*,int isView,struct SrcList_item *);
3123 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
3124 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
3125 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
3126 void sqlite3Vacuum(Parse*);
3127 int sqlite3RunVacuum(char**, sqlite3*);
3128 char *sqlite3NameFromToken(sqlite3*, Token*);
3129 int sqlite3ExprCompare(Expr*, Expr*, int);
3130 int sqlite3ExprListCompare(ExprList*, ExprList*, int);
3131 int sqlite3ExprImpliesExpr(Expr*, Expr*, int);
3132 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
3133 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
3134 int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
3135 Vdbe *sqlite3GetVdbe(Parse*);
3136 void sqlite3PrngSaveState(void);
3137 void sqlite3PrngRestoreState(void);
3138 void sqlite3RollbackAll(sqlite3*,int);
3139 void sqlite3CodeVerifySchema(Parse*, int);
3140 void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
3141 void sqlite3BeginTransaction(Parse*, int);
3142 void sqlite3CommitTransaction(Parse*);
3143 void sqlite3RollbackTransaction(Parse*);
3144 void sqlite3Savepoint(Parse*, int, Token*);
3145 void sqlite3CloseSavepoints(sqlite3 *);
3146 void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
3147 int sqlite3ExprIsConstant(Expr*);
3148 int sqlite3ExprIsConstantNotJoin(Expr*);
3149 int sqlite3ExprIsConstantOrFunction(Expr*);
3150 int sqlite3ExprIsInteger(Expr*, int*);
3151 int sqlite3ExprCanBeNull(const Expr*);
3152 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
3153 int sqlite3IsRowid(const char*);
3154 void sqlite3GenerateRowDelete(Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8);
3155 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*);
3156 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
3157 void sqlite3ResolvePartIdxLabel(Parse*,int);
3158 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
3159                                      u8,u8,int,int*);
3160 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
3161 int sqlite3OpenTableAndIndices(Parse*, Table*, int, int, u8*, int*, int*);
3162 void sqlite3BeginWriteOperation(Parse*, int, int);
3163 void sqlite3MultiWrite(Parse*);
3164 void sqlite3MayAbort(Parse*);
3165 void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
3166 void sqlite3UniqueConstraint(Parse*, int, Index*);
3167 void sqlite3RowidConstraint(Parse*, int, Table*);
3168 Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
3169 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
3170 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
3171 IdList *sqlite3IdListDup(sqlite3*,IdList*);
3172 Select *sqlite3SelectDup(sqlite3*,Select*,int);
3173 void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
3174 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
3175 void sqlite3RegisterBuiltinFunctions(sqlite3*);
3176 void sqlite3RegisterDateTimeFunctions(void);
3177 void sqlite3RegisterGlobalFunctions(void);
3178 int sqlite3SafetyCheckOk(sqlite3*);
3179 int sqlite3SafetyCheckSickOrOk(sqlite3*);
3180 void sqlite3ChangeCookie(Parse*, int);
3181 
3182 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
3183 void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
3184 #endif
3185 
3186 #ifndef SQLITE_OMIT_TRIGGER
3187   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
3188                            Expr*,int, int);
3189   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
3190   void sqlite3DropTrigger(Parse*, SrcList*, int);
3191   void sqlite3DropTriggerPtr(Parse*, Trigger*);
3192   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
3193   Trigger *sqlite3TriggerList(Parse *, Table *);
3194   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
3195                             int, int, int);
3196   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
3197   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
3198   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
3199   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
3200   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
3201                                         Select*,u8);
3202   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
3203   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
3204   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
3205   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
3206   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
3207 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
3208 #else
3209 # define sqlite3TriggersExist(B,C,D,E,F) 0
3210 # define sqlite3DeleteTrigger(A,B)
3211 # define sqlite3DropTriggerPtr(A,B)
3212 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
3213 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
3214 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
3215 # define sqlite3TriggerList(X, Y) 0
3216 # define sqlite3ParseToplevel(p) p
3217 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
3218 #endif
3219 
3220 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
3221 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
3222 void sqlite3DeferForeignKey(Parse*, int);
3223 #ifndef SQLITE_OMIT_AUTHORIZATION
3224   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
3225   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
3226   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
3227   void sqlite3AuthContextPop(AuthContext*);
3228   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
3229 #else
3230 # define sqlite3AuthRead(a,b,c,d)
3231 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
3232 # define sqlite3AuthContextPush(a,b,c)
3233 # define sqlite3AuthContextPop(a)  ((void)(a))
3234 #endif
3235 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
3236 void sqlite3Detach(Parse*, Expr*);
3237 void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
3238 int sqlite3FixSrcList(DbFixer*, SrcList*);
3239 int sqlite3FixSelect(DbFixer*, Select*);
3240 int sqlite3FixExpr(DbFixer*, Expr*);
3241 int sqlite3FixExprList(DbFixer*, ExprList*);
3242 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
3243 int sqlite3AtoF(const char *z, double*, int, u8);
3244 int sqlite3GetInt32(const char *, int*);
3245 int sqlite3Atoi(const char*);
3246 int sqlite3Utf16ByteLen(const void *pData, int nChar);
3247 int sqlite3Utf8CharLen(const char *pData, int nByte);
3248 u32 sqlite3Utf8Read(const u8**);
3249 LogEst sqlite3LogEst(u64);
3250 LogEst sqlite3LogEstAdd(LogEst,LogEst);
3251 #ifndef SQLITE_OMIT_VIRTUALTABLE
3252 LogEst sqlite3LogEstFromDouble(double);
3253 #endif
3254 u64 sqlite3LogEstToInt(LogEst);
3255 
3256 /*
3257 ** Routines to read and write variable-length integers.  These used to
3258 ** be defined locally, but now we use the varint routines in the util.c
3259 ** file.  Code should use the MACRO forms below, as the Varint32 versions
3260 ** are coded to assume the single byte case is already handled (which
3261 ** the MACRO form does).
3262 */
3263 int sqlite3PutVarint(unsigned char*, u64);
3264 int sqlite3PutVarint32(unsigned char*, u32);
3265 u8 sqlite3GetVarint(const unsigned char *, u64 *);
3266 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
3267 int sqlite3VarintLen(u64 v);
3268 
3269 /*
3270 ** The header of a record consists of a sequence variable-length integers.
3271 ** These integers are almost always small and are encoded as a single byte.
3272 ** The following macros take advantage this fact to provide a fast encode
3273 ** and decode of the integers in a record header.  It is faster for the common
3274 ** case where the integer is a single byte.  It is a little slower when the
3275 ** integer is two or more bytes.  But overall it is faster.
3276 **
3277 ** The following expressions are equivalent:
3278 **
3279 **     x = sqlite3GetVarint32( A, &B );
3280 **     x = sqlite3PutVarint32( A, B );
3281 **
3282 **     x = getVarint32( A, B );
3283 **     x = putVarint32( A, B );
3284 **
3285 */
3286 #define getVarint32(A,B)  \
3287   (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
3288 #define putVarint32(A,B)  \
3289   (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
3290   sqlite3PutVarint32((A),(B)))
3291 #define getVarint    sqlite3GetVarint
3292 #define putVarint    sqlite3PutVarint
3293 
3294 
3295 const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
3296 void sqlite3TableAffinity(Vdbe*, Table*, int);
3297 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
3298 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
3299 char sqlite3ExprAffinity(Expr *pExpr);
3300 int sqlite3Atoi64(const char*, i64*, int, u8);
3301 void sqlite3Error(sqlite3*, int, const char*,...);
3302 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
3303 u8 sqlite3HexToInt(int h);
3304 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
3305 
3306 #if defined(SQLITE_TEST)
3307 const char *sqlite3ErrName(int);
3308 #endif
3309 
3310 const char *sqlite3ErrStr(int);
3311 int sqlite3ReadSchema(Parse *pParse);
3312 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
3313 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
3314 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
3315 Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*);
3316 Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
3317 Expr *sqlite3ExprSkipCollate(Expr*);
3318 int sqlite3CheckCollSeq(Parse *, CollSeq *);
3319 int sqlite3CheckObjectName(Parse *, const char *);
3320 void sqlite3VdbeSetChanges(sqlite3 *, int);
3321 int sqlite3AddInt64(i64*,i64);
3322 int sqlite3SubInt64(i64*,i64);
3323 int sqlite3MulInt64(i64*,i64);
3324 int sqlite3AbsInt32(int);
3325 #ifdef SQLITE_ENABLE_8_3_NAMES
3326 void sqlite3FileSuffix3(const char*, char*);
3327 #else
3328 # define sqlite3FileSuffix3(X,Y)
3329 #endif
3330 u8 sqlite3GetBoolean(const char *z,int);
3331 
3332 const void *sqlite3ValueText(sqlite3_value*, u8);
3333 int sqlite3ValueBytes(sqlite3_value*, u8);
3334 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
3335                         void(*)(void*));
3336 void sqlite3ValueSetNull(sqlite3_value*);
3337 void sqlite3ValueFree(sqlite3_value*);
3338 sqlite3_value *sqlite3ValueNew(sqlite3 *);
3339 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
3340 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
3341 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
3342 #ifndef SQLITE_AMALGAMATION
3343 extern const unsigned char sqlite3OpcodeProperty[];
3344 extern const unsigned char sqlite3UpperToLower[];
3345 extern const unsigned char sqlite3CtypeMap[];
3346 extern const Token sqlite3IntTokens[];
3347 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
3348 extern SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
3349 #ifndef SQLITE_OMIT_WSD
3350 extern int sqlite3PendingByte;
3351 #endif
3352 #endif
3353 void sqlite3RootPageMoved(sqlite3*, int, int, int);
3354 void sqlite3Reindex(Parse*, Token*, Token*);
3355 void sqlite3AlterFunctions(void);
3356 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
3357 int sqlite3GetToken(const unsigned char *, int *);
3358 void sqlite3NestedParse(Parse*, const char*, ...);
3359 void sqlite3ExpirePreparedStatements(sqlite3*);
3360 int sqlite3CodeSubselect(Parse *, Expr *, int, int);
3361 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
3362 int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
3363 int sqlite3ResolveExprNames(NameContext*, Expr*);
3364 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
3365 void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
3366 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
3367 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
3368 void sqlite3AlterFinishAddColumn(Parse *, Token *);
3369 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
3370 CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
3371 char sqlite3AffinityType(const char*, u8*);
3372 void sqlite3Analyze(Parse*, Token*, Token*);
3373 int sqlite3InvokeBusyHandler(BusyHandler*);
3374 int sqlite3FindDb(sqlite3*, Token*);
3375 int sqlite3FindDbName(sqlite3 *, const char *);
3376 int sqlite3AnalysisLoad(sqlite3*,int iDB);
3377 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
3378 void sqlite3DefaultRowEst(Index*);
3379 void sqlite3RegisterLikeFunctions(sqlite3*, int);
3380 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
3381 void sqlite3MinimumFileFormat(Parse*, int, int);
3382 void sqlite3SchemaClear(void *);
3383 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
3384 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
3385 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
3386 void sqlite3KeyInfoUnref(KeyInfo*);
3387 KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
3388 KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
3389 #ifdef SQLITE_DEBUG
3390 int sqlite3KeyInfoIsWriteable(KeyInfo*);
3391 #endif
3392 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
3393   void (*)(sqlite3_context*,int,sqlite3_value **),
3394   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
3395   FuncDestructor *pDestructor
3396 );
3397 int sqlite3ApiExit(sqlite3 *db, int);
3398 int sqlite3OpenTempDatabase(Parse *);
3399 
3400 void sqlite3StrAccumInit(StrAccum*, char*, int, int);
3401 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
3402 void sqlite3StrAccumAppendAll(StrAccum*,const char*);
3403 void sqlite3AppendSpace(StrAccum*,int);
3404 char *sqlite3StrAccumFinish(StrAccum*);
3405 void sqlite3StrAccumReset(StrAccum*);
3406 void sqlite3SelectDestInit(SelectDest*,int,int);
3407 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
3408 
3409 void sqlite3BackupRestart(sqlite3_backup *);
3410 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
3411 
3412 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
3413 void sqlite3AnalyzeFunctions(void);
3414 int sqlite3Stat4ProbeSetValue(Parse*,Index*,UnpackedRecord**,Expr*,u8,int,int*);
3415 void sqlite3Stat4ProbeFree(UnpackedRecord*);
3416 #endif
3417 
3418 /*
3419 ** The interface to the LEMON-generated parser
3420 */
3421 void *sqlite3ParserAlloc(void*(*)(size_t));
3422 void sqlite3ParserFree(void*, void(*)(void*));
3423 void sqlite3Parser(void*, int, Token, Parse*);
3424 #ifdef YYTRACKMAXSTACKDEPTH
3425   int sqlite3ParserStackPeak(void*);
3426 #endif
3427 
3428 void sqlite3AutoLoadExtensions(sqlite3*);
3429 #ifndef SQLITE_OMIT_LOAD_EXTENSION
3430   void sqlite3CloseExtensions(sqlite3*);
3431 #else
3432 # define sqlite3CloseExtensions(X)
3433 #endif
3434 
3435 #ifndef SQLITE_OMIT_SHARED_CACHE
3436   void sqlite3TableLock(Parse *, int, int, u8, const char *);
3437 #else
3438   #define sqlite3TableLock(v,w,x,y,z)
3439 #endif
3440 
3441 #ifdef SQLITE_TEST
3442   int sqlite3Utf8To8(unsigned char*);
3443 #endif
3444 
3445 #ifdef SQLITE_OMIT_VIRTUALTABLE
3446 #  define sqlite3VtabClear(Y)
3447 #  define sqlite3VtabSync(X,Y) SQLITE_OK
3448 #  define sqlite3VtabRollback(X)
3449 #  define sqlite3VtabCommit(X)
3450 #  define sqlite3VtabInSync(db) 0
3451 #  define sqlite3VtabLock(X)
3452 #  define sqlite3VtabUnlock(X)
3453 #  define sqlite3VtabUnlockList(X)
3454 #  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
3455 #  define sqlite3GetVTable(X,Y)  ((VTable*)0)
3456 #else
3457    void sqlite3VtabClear(sqlite3 *db, Table*);
3458    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
3459    int sqlite3VtabSync(sqlite3 *db, Vdbe*);
3460    int sqlite3VtabRollback(sqlite3 *db);
3461    int sqlite3VtabCommit(sqlite3 *db);
3462    void sqlite3VtabLock(VTable *);
3463    void sqlite3VtabUnlock(VTable *);
3464    void sqlite3VtabUnlockList(sqlite3*);
3465    int sqlite3VtabSavepoint(sqlite3 *, int, int);
3466    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
3467    VTable *sqlite3GetVTable(sqlite3*, Table*);
3468 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
3469 #endif
3470 void sqlite3VtabMakeWritable(Parse*,Table*);
3471 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
3472 void sqlite3VtabFinishParse(Parse*, Token*);
3473 void sqlite3VtabArgInit(Parse*);
3474 void sqlite3VtabArgExtend(Parse*, Token*);
3475 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
3476 int sqlite3VtabCallConnect(Parse*, Table*);
3477 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
3478 int sqlite3VtabBegin(sqlite3 *, VTable *);
3479 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
3480 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
3481 sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
3482 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
3483 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
3484 void sqlite3ParserReset(Parse*);
3485 int sqlite3Reprepare(Vdbe*);
3486 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
3487 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
3488 int sqlite3TempInMemory(const sqlite3*);
3489 const char *sqlite3JournalModename(int);
3490 #ifndef SQLITE_OMIT_WAL
3491   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
3492   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
3493 #endif
3494 #ifndef SQLITE_OMIT_CTE
3495   With *sqlite3WithAdd(Parse*,With*,Token*,ExprList*,Select*);
3496   void sqlite3WithDelete(sqlite3*,With*);
3497   void sqlite3WithPush(Parse*, With*, u8);
3498 #else
3499 #define sqlite3WithPush(x,y,z)
3500 #define sqlite3WithDelete(x,y)
3501 #endif
3502 
3503 /* Declarations for functions in fkey.c. All of these are replaced by
3504 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
3505 ** key functionality is available. If OMIT_TRIGGER is defined but
3506 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
3507 ** this case foreign keys are parsed, but no other functionality is
3508 ** provided (enforcement of FK constraints requires the triggers sub-system).
3509 */
3510 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
3511   void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
3512   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
3513   void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
3514   int sqlite3FkRequired(Parse*, Table*, int*, int);
3515   u32 sqlite3FkOldmask(Parse*, Table*);
3516   FKey *sqlite3FkReferences(Table *);
3517 #else
3518   #define sqlite3FkActions(a,b,c,d,e,f)
3519   #define sqlite3FkCheck(a,b,c,d,e,f)
3520   #define sqlite3FkDropTable(a,b,c)
3521   #define sqlite3FkOldmask(a,b)         0
3522   #define sqlite3FkRequired(a,b,c,d)    0
3523 #endif
3524 #ifndef SQLITE_OMIT_FOREIGN_KEY
3525   void sqlite3FkDelete(sqlite3 *, Table*);
3526   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
3527 #else
3528   #define sqlite3FkDelete(a,b)
3529   #define sqlite3FkLocateIndex(a,b,c,d,e)
3530 #endif
3531 
3532 
3533 /*
3534 ** Available fault injectors.  Should be numbered beginning with 0.
3535 */
3536 #define SQLITE_FAULTINJECTOR_MALLOC     0
3537 #define SQLITE_FAULTINJECTOR_COUNT      1
3538 
3539 /*
3540 ** The interface to the code in fault.c used for identifying "benign"
3541 ** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
3542 ** is not defined.
3543 */
3544 #ifndef SQLITE_OMIT_BUILTIN_TEST
3545   void sqlite3BeginBenignMalloc(void);
3546   void sqlite3EndBenignMalloc(void);
3547 #else
3548   #define sqlite3BeginBenignMalloc()
3549   #define sqlite3EndBenignMalloc()
3550 #endif
3551 
3552 #define IN_INDEX_ROWID           1
3553 #define IN_INDEX_EPH             2
3554 #define IN_INDEX_INDEX_ASC       3
3555 #define IN_INDEX_INDEX_DESC      4
3556 int sqlite3FindInIndex(Parse *, Expr *, int*);
3557 
3558 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
3559   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
3560   int sqlite3JournalSize(sqlite3_vfs *);
3561   int sqlite3JournalCreate(sqlite3_file *);
3562   int sqlite3JournalExists(sqlite3_file *p);
3563 #else
3564   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
3565   #define sqlite3JournalExists(p) 1
3566 #endif
3567 
3568 void sqlite3MemJournalOpen(sqlite3_file *);
3569 int sqlite3MemJournalSize(void);
3570 int sqlite3IsMemJournal(sqlite3_file *);
3571 
3572 #if SQLITE_MAX_EXPR_DEPTH>0
3573   void sqlite3ExprSetHeight(Parse *pParse, Expr *p);
3574   int sqlite3SelectExprHeight(Select *);
3575   int sqlite3ExprCheckHeight(Parse*, int);
3576 #else
3577   #define sqlite3ExprSetHeight(x,y)
3578   #define sqlite3SelectExprHeight(x) 0
3579   #define sqlite3ExprCheckHeight(x,y)
3580 #endif
3581 
3582 u32 sqlite3Get4byte(const u8*);
3583 void sqlite3Put4byte(u8*, u32);
3584 
3585 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
3586   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
3587   void sqlite3ConnectionUnlocked(sqlite3 *db);
3588   void sqlite3ConnectionClosed(sqlite3 *db);
3589 #else
3590   #define sqlite3ConnectionBlocked(x,y)
3591   #define sqlite3ConnectionUnlocked(x)
3592   #define sqlite3ConnectionClosed(x)
3593 #endif
3594 
3595 #ifdef SQLITE_DEBUG
3596   void sqlite3ParserTrace(FILE*, char *);
3597 #endif
3598 
3599 /*
3600 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
3601 ** sqlite3IoTrace is a pointer to a printf-like routine used to
3602 ** print I/O tracing messages.
3603 */
3604 #ifdef SQLITE_ENABLE_IOTRACE
3605 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
3606   void sqlite3VdbeIOTraceSql(Vdbe*);
3607 SQLITE_EXTERN void (*sqlite3IoTrace)(const char*,...);
3608 #else
3609 # define IOTRACE(A)
3610 # define sqlite3VdbeIOTraceSql(X)
3611 #endif
3612 
3613 /*
3614 ** These routines are available for the mem2.c debugging memory allocator
3615 ** only.  They are used to verify that different "types" of memory
3616 ** allocations are properly tracked by the system.
3617 **
3618 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
3619 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
3620 ** a single bit set.
3621 **
3622 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
3623 ** argument match the type set by the previous sqlite3MemdebugSetType().
3624 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
3625 **
3626 ** sqlite3MemdebugNoType() returns true if none of the bits in its second
3627 ** argument match the type set by the previous sqlite3MemdebugSetType().
3628 **
3629 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
3630 ** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
3631 ** it might have been allocated by lookaside, except the allocation was
3632 ** too large or lookaside was already full.  It is important to verify
3633 ** that allocations that might have been satisfied by lookaside are not
3634 ** passed back to non-lookaside free() routines.  Asserts such as the
3635 ** example above are placed on the non-lookaside free() routines to verify
3636 ** this constraint.
3637 **
3638 ** All of this is no-op for a production build.  It only comes into
3639 ** play when the SQLITE_MEMDEBUG compile-time option is used.
3640 */
3641 #ifdef SQLITE_MEMDEBUG
3642   void sqlite3MemdebugSetType(void*,u8);
3643   int sqlite3MemdebugHasType(void*,u8);
3644   int sqlite3MemdebugNoType(void*,u8);
3645 #else
3646 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
3647 # define sqlite3MemdebugHasType(X,Y)  1
3648 # define sqlite3MemdebugNoType(X,Y)   1
3649 #endif
3650 #define MEMTYPE_HEAP       0x01  /* General heap allocations */
3651 #define MEMTYPE_LOOKASIDE  0x02  /* Might have been lookaside memory */
3652 #define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
3653 #define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
3654 #define MEMTYPE_DB         0x10  /* Uses sqlite3DbMalloc, not sqlite_malloc */
3655 
3656 #endif /* _SQLITEINT_H_ */
3657