xref: /sqlite-3.40.0/src/sqliteInt.h (revision d4530979)
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 ** A macro to hint to the compiler that a function should not be
158 ** inlined.
159 */
160 #if defined(__GNUC__)
161 #  define SQLITE_NOINLINE  __attribute__((noinline))
162 #elif defined(_MSC_VER)
163 #  define SQLITE_NOINLINE  __declspec(noinline)
164 #else
165 #  define SQLITE_NOINLINE
166 #endif
167 
168 /*
169 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
170 ** 0 means mutexes are permanently disable and the library is never
171 ** threadsafe.  1 means the library is serialized which is the highest
172 ** level of threadsafety.  2 means the library is multithreaded - multiple
173 ** threads can use SQLite as long as no two threads try to use the same
174 ** database connection at the same time.
175 **
176 ** Older versions of SQLite used an optional THREADSAFE macro.
177 ** We support that for legacy.
178 */
179 #if !defined(SQLITE_THREADSAFE)
180 # if defined(THREADSAFE)
181 #   define SQLITE_THREADSAFE THREADSAFE
182 # else
183 #   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
184 # endif
185 #endif
186 
187 /*
188 ** Powersafe overwrite is on by default.  But can be turned off using
189 ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
190 */
191 #ifndef SQLITE_POWERSAFE_OVERWRITE
192 # define SQLITE_POWERSAFE_OVERWRITE 1
193 #endif
194 
195 /*
196 ** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
197 ** It determines whether or not the features related to
198 ** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
199 ** be overridden at runtime using the sqlite3_config() API.
200 */
201 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
202 # define SQLITE_DEFAULT_MEMSTATUS 1
203 #endif
204 
205 /*
206 ** Exactly one of the following macros must be defined in order to
207 ** specify which memory allocation subsystem to use.
208 **
209 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
210 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
211 **     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
212 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
213 **
214 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
215 ** assert() macro is enabled, each call into the Win32 native heap subsystem
216 ** will cause HeapValidate to be called.  If heap validation should fail, an
217 ** assertion will be triggered.
218 **
219 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
220 ** the default.
221 */
222 #if defined(SQLITE_SYSTEM_MALLOC) \
223   + defined(SQLITE_WIN32_MALLOC) \
224   + defined(SQLITE_ZERO_MALLOC) \
225   + defined(SQLITE_MEMDEBUG)>1
226 # error "Two or more of the following compile-time configuration options\
227  are defined but at most one is allowed:\
228  SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
229  SQLITE_ZERO_MALLOC"
230 #endif
231 #if defined(SQLITE_SYSTEM_MALLOC) \
232   + defined(SQLITE_WIN32_MALLOC) \
233   + defined(SQLITE_ZERO_MALLOC) \
234   + defined(SQLITE_MEMDEBUG)==0
235 # define SQLITE_SYSTEM_MALLOC 1
236 #endif
237 
238 /*
239 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
240 ** sizes of memory allocations below this value where possible.
241 */
242 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
243 # define SQLITE_MALLOC_SOFT_LIMIT 1024
244 #endif
245 
246 /*
247 ** We need to define _XOPEN_SOURCE as follows in order to enable
248 ** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
249 ** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
250 ** it.
251 */
252 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
253 #  define _XOPEN_SOURCE 600
254 #endif
255 
256 /*
257 ** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
258 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
259 ** make it true by defining or undefining NDEBUG.
260 **
261 ** Setting NDEBUG makes the code smaller and faster by disabling the
262 ** assert() statements in the code.  So we want the default action
263 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
264 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
265 ** feature.
266 */
267 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
268 # define NDEBUG 1
269 #endif
270 #if defined(NDEBUG) && defined(SQLITE_DEBUG)
271 # undef NDEBUG
272 #endif
273 
274 /*
275 ** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
276 */
277 #if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
278 # define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
279 #endif
280 
281 /*
282 ** The testcase() macro is used to aid in coverage testing.  When
283 ** doing coverage testing, the condition inside the argument to
284 ** testcase() must be evaluated both true and false in order to
285 ** get full branch coverage.  The testcase() macro is inserted
286 ** to help ensure adequate test coverage in places where simple
287 ** condition/decision coverage is inadequate.  For example, testcase()
288 ** can be used to make sure boundary values are tested.  For
289 ** bitmask tests, testcase() can be used to make sure each bit
290 ** is significant and used at least once.  On switch statements
291 ** where multiple cases go to the same block of code, testcase()
292 ** can insure that all cases are evaluated.
293 **
294 */
295 #ifdef SQLITE_COVERAGE_TEST
296   void sqlite3Coverage(int);
297 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
298 #else
299 # define testcase(X)
300 #endif
301 
302 /*
303 ** The TESTONLY macro is used to enclose variable declarations or
304 ** other bits of code that are needed to support the arguments
305 ** within testcase() and assert() macros.
306 */
307 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
308 # define TESTONLY(X)  X
309 #else
310 # define TESTONLY(X)
311 #endif
312 
313 /*
314 ** Sometimes we need a small amount of code such as a variable initialization
315 ** to setup for a later assert() statement.  We do not want this code to
316 ** appear when assert() is disabled.  The following macro is therefore
317 ** used to contain that setup code.  The "VVA" acronym stands for
318 ** "Verification, Validation, and Accreditation".  In other words, the
319 ** code within VVA_ONLY() will only run during verification processes.
320 */
321 #ifndef NDEBUG
322 # define VVA_ONLY(X)  X
323 #else
324 # define VVA_ONLY(X)
325 #endif
326 
327 /*
328 ** The ALWAYS and NEVER macros surround boolean expressions which
329 ** are intended to always be true or false, respectively.  Such
330 ** expressions could be omitted from the code completely.  But they
331 ** are included in a few cases in order to enhance the resilience
332 ** of SQLite to unexpected behavior - to make the code "self-healing"
333 ** or "ductile" rather than being "brittle" and crashing at the first
334 ** hint of unplanned behavior.
335 **
336 ** In other words, ALWAYS and NEVER are added for defensive code.
337 **
338 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
339 ** be true and false so that the unreachable code they specify will
340 ** not be counted as untested code.
341 */
342 #if defined(SQLITE_COVERAGE_TEST)
343 # define ALWAYS(X)      (1)
344 # define NEVER(X)       (0)
345 #elif !defined(NDEBUG)
346 # define ALWAYS(X)      ((X)?1:(assert(0),0))
347 # define NEVER(X)       ((X)?(assert(0),1):0)
348 #else
349 # define ALWAYS(X)      (X)
350 # define NEVER(X)       (X)
351 #endif
352 
353 /*
354 ** Return true (non-zero) if the input is an integer that is too large
355 ** to fit in 32-bits.  This macro is used inside of various testcase()
356 ** macros to verify that we have tested SQLite for large-file support.
357 */
358 #define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
359 
360 /*
361 ** The macro unlikely() is a hint that surrounds a boolean
362 ** expression that is usually false.  Macro likely() surrounds
363 ** a boolean expression that is usually true.  These hints could,
364 ** in theory, be used by the compiler to generate better code, but
365 ** currently they are just comments for human readers.
366 */
367 #define likely(X)    (X)
368 #define unlikely(X)  (X)
369 
370 #include "hash.h"
371 #include "parse.h"
372 #include <stdio.h>
373 #include <stdlib.h>
374 #include <string.h>
375 #include <assert.h>
376 #include <stddef.h>
377 
378 /*
379 ** If compiling for a processor that lacks floating point support,
380 ** substitute integer for floating-point
381 */
382 #ifdef SQLITE_OMIT_FLOATING_POINT
383 # define double sqlite_int64
384 # define float sqlite_int64
385 # define LONGDOUBLE_TYPE sqlite_int64
386 # ifndef SQLITE_BIG_DBL
387 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
388 # endif
389 # define SQLITE_OMIT_DATETIME_FUNCS 1
390 # define SQLITE_OMIT_TRACE 1
391 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
392 # undef SQLITE_HAVE_ISNAN
393 #endif
394 #ifndef SQLITE_BIG_DBL
395 # define SQLITE_BIG_DBL (1e99)
396 #endif
397 
398 /*
399 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
400 ** afterward. Having this macro allows us to cause the C compiler
401 ** to omit code used by TEMP tables without messy #ifndef statements.
402 */
403 #ifdef SQLITE_OMIT_TEMPDB
404 #define OMIT_TEMPDB 1
405 #else
406 #define OMIT_TEMPDB 0
407 #endif
408 
409 /*
410 ** The "file format" number is an integer that is incremented whenever
411 ** the VDBE-level file format changes.  The following macros define the
412 ** the default file format for new databases and the maximum file format
413 ** that the library can read.
414 */
415 #define SQLITE_MAX_FILE_FORMAT 4
416 #ifndef SQLITE_DEFAULT_FILE_FORMAT
417 # define SQLITE_DEFAULT_FILE_FORMAT 4
418 #endif
419 
420 /*
421 ** Determine whether triggers are recursive by default.  This can be
422 ** changed at run-time using a pragma.
423 */
424 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
425 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
426 #endif
427 
428 /*
429 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
430 ** on the command-line
431 */
432 #ifndef SQLITE_TEMP_STORE
433 # define SQLITE_TEMP_STORE 1
434 # define SQLITE_TEMP_STORE_xc 1  /* Exclude from ctime.c */
435 #endif
436 
437 /*
438 ** If no value has been provided for SQLITE_MAX_WORKER_THREADS, or if
439 ** SQLITE_TEMP_STORE is set to 3 (never use temporary files), set it
440 ** to zero.
441 */
442 #if SQLITE_TEMP_STORE==3 || SQLITE_THREADSAFE==0
443 # undef SQLITE_MAX_WORKER_THREADS
444 # define SQLITE_MAX_WORKER_THREADS 0
445 #endif
446 #ifndef SQLITE_MAX_WORKER_THREADS
447 # define SQLITE_MAX_WORKER_THREADS 8
448 #endif
449 #ifndef SQLITE_DEFAULT_WORKER_THREADS
450 # define SQLITE_DEFAULT_WORKER_THREADS 0
451 #endif
452 #if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
453 # undef SQLITE_MAX_WORKER_THREADS
454 # define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
455 #endif
456 
457 
458 /*
459 ** GCC does not define the offsetof() macro so we'll have to do it
460 ** ourselves.
461 */
462 #ifndef offsetof
463 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
464 #endif
465 
466 /*
467 ** Macros to compute minimum and maximum of two numbers.
468 */
469 #define MIN(A,B) ((A)<(B)?(A):(B))
470 #define MAX(A,B) ((A)>(B)?(A):(B))
471 
472 /*
473 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
474 ** not, there are still machines out there that use EBCDIC.)
475 */
476 #if 'A' == '\301'
477 # define SQLITE_EBCDIC 1
478 #else
479 # define SQLITE_ASCII 1
480 #endif
481 
482 /*
483 ** Integers of known sizes.  These typedefs might change for architectures
484 ** where the sizes very.  Preprocessor macros are available so that the
485 ** types can be conveniently redefined at compile-type.  Like this:
486 **
487 **         cc '-DUINTPTR_TYPE=long long int' ...
488 */
489 #ifndef UINT32_TYPE
490 # ifdef HAVE_UINT32_T
491 #  define UINT32_TYPE uint32_t
492 # else
493 #  define UINT32_TYPE unsigned int
494 # endif
495 #endif
496 #ifndef UINT16_TYPE
497 # ifdef HAVE_UINT16_T
498 #  define UINT16_TYPE uint16_t
499 # else
500 #  define UINT16_TYPE unsigned short int
501 # endif
502 #endif
503 #ifndef INT16_TYPE
504 # ifdef HAVE_INT16_T
505 #  define INT16_TYPE int16_t
506 # else
507 #  define INT16_TYPE short int
508 # endif
509 #endif
510 #ifndef UINT8_TYPE
511 # ifdef HAVE_UINT8_T
512 #  define UINT8_TYPE uint8_t
513 # else
514 #  define UINT8_TYPE unsigned char
515 # endif
516 #endif
517 #ifndef INT8_TYPE
518 # ifdef HAVE_INT8_T
519 #  define INT8_TYPE int8_t
520 # else
521 #  define INT8_TYPE signed char
522 # endif
523 #endif
524 #ifndef LONGDOUBLE_TYPE
525 # define LONGDOUBLE_TYPE long double
526 #endif
527 typedef sqlite_int64 i64;          /* 8-byte signed integer */
528 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
529 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
530 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
531 typedef INT16_TYPE i16;            /* 2-byte signed integer */
532 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
533 typedef INT8_TYPE i8;              /* 1-byte signed integer */
534 
535 /*
536 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
537 ** that can be stored in a u32 without loss of data.  The value
538 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
539 ** have to specify the value in the less intuitive manner shown:
540 */
541 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
542 
543 /*
544 ** The datatype used to store estimates of the number of rows in a
545 ** table or index.  This is an unsigned integer type.  For 99.9% of
546 ** the world, a 32-bit integer is sufficient.  But a 64-bit integer
547 ** can be used at compile-time if desired.
548 */
549 #ifdef SQLITE_64BIT_STATS
550  typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
551 #else
552  typedef u32 tRowcnt;    /* 32-bit is the default */
553 #endif
554 
555 /*
556 ** Estimated quantities used for query planning are stored as 16-bit
557 ** logarithms.  For quantity X, the value stored is 10*log2(X).  This
558 ** gives a possible range of values of approximately 1.0e986 to 1e-986.
559 ** But the allowed values are "grainy".  Not every value is representable.
560 ** For example, quantities 16 and 17 are both represented by a LogEst
561 ** of 40.  However, since LogEst quantaties are suppose to be estimates,
562 ** not exact values, this imprecision is not a problem.
563 **
564 ** "LogEst" is short for "Logarithmic Estimate".
565 **
566 ** Examples:
567 **      1 -> 0              20 -> 43          10000 -> 132
568 **      2 -> 10             25 -> 46          25000 -> 146
569 **      3 -> 16            100 -> 66        1000000 -> 199
570 **      4 -> 20           1000 -> 99        1048576 -> 200
571 **     10 -> 33           1024 -> 100    4294967296 -> 320
572 **
573 ** The LogEst can be negative to indicate fractional values.
574 ** Examples:
575 **
576 **    0.5 -> -10           0.1 -> -33        0.0625 -> -40
577 */
578 typedef INT16_TYPE LogEst;
579 
580 /*
581 ** Macros to determine whether the machine is big or little endian,
582 ** and whether or not that determination is run-time or compile-time.
583 **
584 ** For best performance, an attempt is made to guess at the byte-order
585 ** using C-preprocessor macros.  If that is unsuccessful, or if
586 ** -DSQLITE_RUNTIME_BYTEORDER=1 is set, then byte-order is determined
587 ** at run-time.
588 */
589 #ifdef SQLITE_AMALGAMATION
590 const int sqlite3one = 1;
591 #else
592 extern const int sqlite3one;
593 #endif
594 #if (defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
595      defined(__x86_64) || defined(__x86_64__) || defined(_M_X64)  ||    \
596      defined(_M_AMD64) || defined(_M_ARM)     || defined(__x86)   ||    \
597      defined(__arm__)) && !defined(SQLITE_RUNTIME_BYTEORDER)
598 # define SQLITE_BYTEORDER    1234
599 # define SQLITE_BIGENDIAN    0
600 # define SQLITE_LITTLEENDIAN 1
601 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
602 #endif
603 #if (defined(sparc)    || defined(__ppc__))  \
604     && !defined(SQLITE_RUNTIME_BYTEORDER)
605 # define SQLITE_BYTEORDER    4321
606 # define SQLITE_BIGENDIAN    1
607 # define SQLITE_LITTLEENDIAN 0
608 # define SQLITE_UTF16NATIVE  SQLITE_UTF16BE
609 #endif
610 #if !defined(SQLITE_BYTEORDER)
611 # define SQLITE_BYTEORDER    0     /* 0 means "unknown at compile-time" */
612 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
613 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
614 # define SQLITE_UTF16NATIVE  (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
615 #endif
616 
617 /*
618 ** Constants for the largest and smallest possible 64-bit signed integers.
619 ** These macros are designed to work correctly on both 32-bit and 64-bit
620 ** compilers.
621 */
622 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
623 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
624 
625 /*
626 ** Round up a number to the next larger multiple of 8.  This is used
627 ** to force 8-byte alignment on 64-bit architectures.
628 */
629 #define ROUND8(x)     (((x)+7)&~7)
630 
631 /*
632 ** Round down to the nearest multiple of 8
633 */
634 #define ROUNDDOWN8(x) ((x)&~7)
635 
636 /*
637 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
638 ** macro is used only within assert() to verify that the code gets
639 ** all alignment restrictions correct.
640 **
641 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
642 ** underlying malloc() implementation might return us 4-byte aligned
643 ** pointers.  In that case, only verify 4-byte alignment.
644 */
645 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
646 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
647 #else
648 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
649 #endif
650 
651 /*
652 ** Disable MMAP on platforms where it is known to not work
653 */
654 #if defined(__OpenBSD__) || defined(__QNXNTO__)
655 # undef SQLITE_MAX_MMAP_SIZE
656 # define SQLITE_MAX_MMAP_SIZE 0
657 #endif
658 
659 /*
660 ** Default maximum size of memory used by memory-mapped I/O in the VFS
661 */
662 #ifdef __APPLE__
663 # include <TargetConditionals.h>
664 # if TARGET_OS_IPHONE
665 #   undef SQLITE_MAX_MMAP_SIZE
666 #   define SQLITE_MAX_MMAP_SIZE 0
667 # endif
668 #endif
669 #ifndef SQLITE_MAX_MMAP_SIZE
670 # if defined(__linux__) \
671   || defined(_WIN32) \
672   || (defined(__APPLE__) && defined(__MACH__)) \
673   || defined(__sun)
674 #   define SQLITE_MAX_MMAP_SIZE 0x7fff0000  /* 2147418112 */
675 # else
676 #   define SQLITE_MAX_MMAP_SIZE 0
677 # endif
678 # define SQLITE_MAX_MMAP_SIZE_xc 1 /* exclude from ctime.c */
679 #endif
680 
681 /*
682 ** The default MMAP_SIZE is zero on all platforms.  Or, even if a larger
683 ** default MMAP_SIZE is specified at compile-time, make sure that it does
684 ** not exceed the maximum mmap size.
685 */
686 #ifndef SQLITE_DEFAULT_MMAP_SIZE
687 # define SQLITE_DEFAULT_MMAP_SIZE 0
688 # define SQLITE_DEFAULT_MMAP_SIZE_xc 1  /* Exclude from ctime.c */
689 #endif
690 #if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
691 # undef SQLITE_DEFAULT_MMAP_SIZE
692 # define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
693 #endif
694 
695 /*
696 ** Only one of SQLITE_ENABLE_STAT3 or SQLITE_ENABLE_STAT4 can be defined.
697 ** Priority is given to SQLITE_ENABLE_STAT4.  If either are defined, also
698 ** define SQLITE_ENABLE_STAT3_OR_STAT4
699 */
700 #ifdef SQLITE_ENABLE_STAT4
701 # undef SQLITE_ENABLE_STAT3
702 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
703 #elif SQLITE_ENABLE_STAT3
704 # define SQLITE_ENABLE_STAT3_OR_STAT4 1
705 #elif SQLITE_ENABLE_STAT3_OR_STAT4
706 # undef SQLITE_ENABLE_STAT3_OR_STAT4
707 #endif
708 
709 /*
710 ** An instance of the following structure is used to store the busy-handler
711 ** callback for a given sqlite handle.
712 **
713 ** The sqlite.busyHandler member of the sqlite struct contains the busy
714 ** callback for the database handle. Each pager opened via the sqlite
715 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
716 ** callback is currently invoked only from within pager.c.
717 */
718 typedef struct BusyHandler BusyHandler;
719 struct BusyHandler {
720   int (*xFunc)(void *,int);  /* The busy callback */
721   void *pArg;                /* First arg to busy callback */
722   int nBusy;                 /* Incremented with each busy call */
723 };
724 
725 /*
726 ** Name of the master database table.  The master database table
727 ** is a special table that holds the names and attributes of all
728 ** user tables and indices.
729 */
730 #define MASTER_NAME       "sqlite_master"
731 #define TEMP_MASTER_NAME  "sqlite_temp_master"
732 
733 /*
734 ** The root-page of the master database table.
735 */
736 #define MASTER_ROOT       1
737 
738 /*
739 ** The name of the schema table.
740 */
741 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
742 
743 /*
744 ** A convenience macro that returns the number of elements in
745 ** an array.
746 */
747 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
748 
749 /*
750 ** Determine if the argument is a power of two
751 */
752 #define IsPowerOfTwo(X) (((X)&((X)-1))==0)
753 
754 /*
755 ** The following value as a destructor means to use sqlite3DbFree().
756 ** The sqlite3DbFree() routine requires two parameters instead of the
757 ** one parameter that destructors normally want.  So we have to introduce
758 ** this magic value that the code knows to handle differently.  Any
759 ** pointer will work here as long as it is distinct from SQLITE_STATIC
760 ** and SQLITE_TRANSIENT.
761 */
762 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3MallocSize)
763 
764 /*
765 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
766 ** not support Writable Static Data (WSD) such as global and static variables.
767 ** All variables must either be on the stack or dynamically allocated from
768 ** the heap.  When WSD is unsupported, the variable declarations scattered
769 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
770 ** macro is used for this purpose.  And instead of referencing the variable
771 ** directly, we use its constant as a key to lookup the run-time allocated
772 ** buffer that holds real variable.  The constant is also the initializer
773 ** for the run-time allocated buffer.
774 **
775 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
776 ** macros become no-ops and have zero performance impact.
777 */
778 #ifdef SQLITE_OMIT_WSD
779   #define SQLITE_WSD const
780   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
781   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
782   int sqlite3_wsd_init(int N, int J);
783   void *sqlite3_wsd_find(void *K, int L);
784 #else
785   #define SQLITE_WSD
786   #define GLOBAL(t,v) v
787   #define sqlite3GlobalConfig sqlite3Config
788 #endif
789 
790 /*
791 ** The following macros are used to suppress compiler warnings and to
792 ** make it clear to human readers when a function parameter is deliberately
793 ** left unused within the body of a function. This usually happens when
794 ** a function is called via a function pointer. For example the
795 ** implementation of an SQL aggregate step callback may not use the
796 ** parameter indicating the number of arguments passed to the aggregate,
797 ** if it knows that this is enforced elsewhere.
798 **
799 ** When a function parameter is not used at all within the body of a function,
800 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
801 ** However, these macros may also be used to suppress warnings related to
802 ** parameters that may or may not be used depending on compilation options.
803 ** For example those parameters only used in assert() statements. In these
804 ** cases the parameters are named as per the usual conventions.
805 */
806 #define UNUSED_PARAMETER(x) (void)(x)
807 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
808 
809 /*
810 ** Forward references to structures
811 */
812 typedef struct AggInfo AggInfo;
813 typedef struct AuthContext AuthContext;
814 typedef struct AutoincInfo AutoincInfo;
815 typedef struct Bitvec Bitvec;
816 typedef struct CollSeq CollSeq;
817 typedef struct Column Column;
818 typedef struct Db Db;
819 typedef struct Schema Schema;
820 typedef struct Expr Expr;
821 typedef struct ExprList ExprList;
822 typedef struct ExprSpan ExprSpan;
823 typedef struct FKey FKey;
824 typedef struct FuncDestructor FuncDestructor;
825 typedef struct FuncDef FuncDef;
826 typedef struct FuncDefHash FuncDefHash;
827 typedef struct IdList IdList;
828 typedef struct Index Index;
829 typedef struct IndexSample IndexSample;
830 typedef struct KeyClass KeyClass;
831 typedef struct KeyInfo KeyInfo;
832 typedef struct Lookaside Lookaside;
833 typedef struct LookasideSlot LookasideSlot;
834 typedef struct Module Module;
835 typedef struct NameContext NameContext;
836 typedef struct Parse Parse;
837 typedef struct PrintfArguments PrintfArguments;
838 typedef struct RowSet RowSet;
839 typedef struct Savepoint Savepoint;
840 typedef struct Select Select;
841 typedef struct SQLiteThread SQLiteThread;
842 typedef struct SelectDest SelectDest;
843 typedef struct SrcList SrcList;
844 typedef struct StrAccum StrAccum;
845 typedef struct Table Table;
846 typedef struct TableLock TableLock;
847 typedef struct Token Token;
848 typedef struct Trigger Trigger;
849 typedef struct TriggerPrg TriggerPrg;
850 typedef struct TriggerStep TriggerStep;
851 typedef struct UnpackedRecord UnpackedRecord;
852 typedef struct VTable VTable;
853 typedef struct VtabCtx VtabCtx;
854 typedef struct Walker Walker;
855 typedef struct WhereInfo WhereInfo;
856 typedef struct With With;
857 
858 /*
859 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
860 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
861 ** pointer types (i.e. FuncDef) defined above.
862 */
863 #include "btree.h"
864 #include "vdbe.h"
865 #include "pager.h"
866 #include "pcache.h"
867 
868 #include "os.h"
869 #include "mutex.h"
870 
871 
872 /*
873 ** Each database file to be accessed by the system is an instance
874 ** of the following structure.  There are normally two of these structures
875 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
876 ** aDb[1] is the database file used to hold temporary tables.  Additional
877 ** databases may be attached.
878 */
879 struct Db {
880   char *zName;         /* Name of this database */
881   Btree *pBt;          /* The B*Tree structure for this database file */
882   u8 safety_level;     /* How aggressive at syncing data to disk */
883   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
884 };
885 
886 /*
887 ** An instance of the following structure stores a database schema.
888 **
889 ** Most Schema objects are associated with a Btree.  The exception is
890 ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
891 ** In shared cache mode, a single Schema object can be shared by multiple
892 ** Btrees that refer to the same underlying BtShared object.
893 **
894 ** Schema objects are automatically deallocated when the last Btree that
895 ** references them is destroyed.   The TEMP Schema is manually freed by
896 ** sqlite3_close().
897 *
898 ** A thread must be holding a mutex on the corresponding Btree in order
899 ** to access Schema content.  This implies that the thread must also be
900 ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
901 ** For a TEMP Schema, only the connection mutex is required.
902 */
903 struct Schema {
904   int schema_cookie;   /* Database schema version number for this file */
905   int iGeneration;     /* Generation counter.  Incremented with each change */
906   Hash tblHash;        /* All tables indexed by name */
907   Hash idxHash;        /* All (named) indices indexed by name */
908   Hash trigHash;       /* All triggers indexed by name */
909   Hash fkeyHash;       /* All foreign keys by referenced table name */
910   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
911   u8 file_format;      /* Schema format version for this file */
912   u8 enc;              /* Text encoding used by this database */
913   u16 schemaFlags;     /* Flags associated with this schema */
914   int cache_size;      /* Number of pages to use in the cache */
915 };
916 
917 /*
918 ** These macros can be used to test, set, or clear bits in the
919 ** Db.pSchema->flags field.
920 */
921 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))
922 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->schemaFlags&(P))!=0)
923 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->schemaFlags|=(P)
924 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->schemaFlags&=~(P)
925 
926 /*
927 ** Allowed values for the DB.pSchema->flags field.
928 **
929 ** The DB_SchemaLoaded flag is set after the database schema has been
930 ** read into internal hash tables.
931 **
932 ** DB_UnresetViews means that one or more views have column names that
933 ** have been filled out.  If the schema changes, these column names might
934 ** changes and so the view will need to be reset.
935 */
936 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
937 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
938 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
939 
940 /*
941 ** The number of different kinds of things that can be limited
942 ** using the sqlite3_limit() interface.
943 */
944 #define SQLITE_N_LIMIT (SQLITE_LIMIT_WORKER_THREADS+1)
945 
946 /*
947 ** Lookaside malloc is a set of fixed-size buffers that can be used
948 ** to satisfy small transient memory allocation requests for objects
949 ** associated with a particular database connection.  The use of
950 ** lookaside malloc provides a significant performance enhancement
951 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
952 ** SQL statements.
953 **
954 ** The Lookaside structure holds configuration information about the
955 ** lookaside malloc subsystem.  Each available memory allocation in
956 ** the lookaside subsystem is stored on a linked list of LookasideSlot
957 ** objects.
958 **
959 ** Lookaside allocations are only allowed for objects that are associated
960 ** with a particular database connection.  Hence, schema information cannot
961 ** be stored in lookaside because in shared cache mode the schema information
962 ** is shared by multiple database connections.  Therefore, while parsing
963 ** schema information, the Lookaside.bEnabled flag is cleared so that
964 ** lookaside allocations are not used to construct the schema objects.
965 */
966 struct Lookaside {
967   u16 sz;                 /* Size of each buffer in bytes */
968   u8 bEnabled;            /* False to disable new lookaside allocations */
969   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
970   int nOut;               /* Number of buffers currently checked out */
971   int mxOut;              /* Highwater mark for nOut */
972   int anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
973   LookasideSlot *pFree;   /* List of available buffers */
974   void *pStart;           /* First byte of available memory space */
975   void *pEnd;             /* First byte past end of available space */
976 };
977 struct LookasideSlot {
978   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
979 };
980 
981 /*
982 ** A hash table for function definitions.
983 **
984 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
985 ** Collisions are on the FuncDef.pHash chain.
986 */
987 struct FuncDefHash {
988   FuncDef *a[23];       /* Hash table for functions */
989 };
990 
991 #ifdef SQLITE_USER_AUTHENTICATION
992 /*
993 ** Information held in the "sqlite3" database connection object and used
994 ** to manage user authentication.
995 */
996 typedef struct sqlite3_userauth sqlite3_userauth;
997 struct sqlite3_userauth {
998   u8 authFlags;                 /* Status flags for user authentication */
999   int nAuthPW;                  /* Size of the zAuthPW in bytes */
1000   char *zAuthPW;                /* Password used to authenticate */
1001   char *zAuthUser;              /* User name used to authenticate */
1002 };
1003 
1004 /* Allowed values for sqlite3_userauth.authFlags */
1005 #define UAUTH_Ovrd        0x01  /* Do not enforce access restrictions */
1006 #define UAUTH_Auth        0x02  /* True if the user has authenticated */
1007 #define UAUTH_Admin       0x04  /* True if the user is an administrator */
1008 #define UAUTH_AuthReqd    0x08  /* True if main has an sqlite_user table */
1009 
1010 /* Macros for accessing sqlite3.auth.authFlags */
1011 #define DbIsAuth(D)       (((D)->auth.authFlags&UAUTH_Auth)!=0)
1012 #define DbIsAdmin(D)      (((D)->auth.authFlags&UAUTH_Admin)!=0)
1013 
1014 /* Functions used only by user authorization logic */
1015 int sqlite3UserAuthTable(const char*);
1016 
1017 #endif /* SQLITE_USER_AUTHENTICATION */
1018 
1019 
1020 /*
1021 ** Each database connection is an instance of the following structure.
1022 */
1023 struct sqlite3 {
1024   sqlite3_vfs *pVfs;            /* OS Interface */
1025   struct Vdbe *pVdbe;           /* List of active virtual machines */
1026   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
1027   sqlite3_mutex *mutex;         /* Connection mutex */
1028   Db *aDb;                      /* All backends */
1029   int nDb;                      /* Number of backends currently in use */
1030   int flags;                    /* Miscellaneous flags. See below */
1031   i64 lastRowid;                /* ROWID of most recent insert (see above) */
1032   i64 szMmap;                   /* Default mmap_size setting */
1033   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
1034   int errCode;                  /* Most recent error code (SQLITE_*) */
1035   int errMask;                  /* & result codes with this before returning */
1036   u16 dbOptFlags;               /* Flags to enable/disable optimizations */
1037   u8 autoCommit;                /* The auto-commit flag. */
1038   u8 temp_store;                /* 1: file 2: memory 0: default */
1039   u8 mallocFailed;              /* True if we have seen a malloc failure */
1040   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
1041   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
1042   u8 suppressErr;               /* Do not issue error messages if true */
1043   u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
1044   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
1045   int nextPagesize;             /* Pagesize after VACUUM if >0 */
1046   u32 magic;                    /* Magic number for detect library misuse */
1047   int nChange;                  /* Value returned by sqlite3_changes() */
1048   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
1049   int aLimit[SQLITE_N_LIMIT];   /* Limits */
1050   int nMaxSorterMmap;           /* Maximum size of regions mapped by sorter */
1051   struct sqlite3InitInfo {      /* Information used during initialization */
1052     int newTnum;                /* Rootpage of table being initialized */
1053     u8 iDb;                     /* Which db file is being initialized */
1054     u8 busy;                    /* TRUE if currently initializing */
1055     u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
1056   } init;
1057   int nVdbeActive;              /* Number of VDBEs currently running */
1058   int nVdbeRead;                /* Number of active VDBEs that read or write */
1059   int nVdbeWrite;               /* Number of active VDBEs that read and write */
1060   int nVdbeExec;                /* Number of nested calls to VdbeExec() */
1061   int nExtension;               /* Number of loaded extensions */
1062   void **aExtension;            /* Array of shared library handles */
1063   void (*xTrace)(void*,const char*);        /* Trace function */
1064   void *pTraceArg;                          /* Argument to the trace function */
1065   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
1066   void *pProfileArg;                        /* Argument to profile function */
1067   void *pCommitArg;                 /* Argument to xCommitCallback() */
1068   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
1069   void *pRollbackArg;               /* Argument to xRollbackCallback() */
1070   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
1071   void *pUpdateArg;
1072   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
1073 #ifndef SQLITE_OMIT_WAL
1074   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
1075   void *pWalArg;
1076 #endif
1077   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
1078   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
1079   void *pCollNeededArg;
1080   sqlite3_value *pErr;          /* Most recent error message */
1081   union {
1082     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
1083     double notUsed1;            /* Spacer */
1084   } u1;
1085   Lookaside lookaside;          /* Lookaside malloc configuration */
1086 #ifndef SQLITE_OMIT_AUTHORIZATION
1087   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
1088                                 /* Access authorization function */
1089   void *pAuthArg;               /* 1st argument to the access auth function */
1090 #endif
1091 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
1092   int (*xProgress)(void *);     /* The progress callback */
1093   void *pProgressArg;           /* Argument to the progress callback */
1094   unsigned nProgressOps;        /* Number of opcodes for progress callback */
1095 #endif
1096 #ifndef SQLITE_OMIT_VIRTUALTABLE
1097   int nVTrans;                  /* Allocated size of aVTrans */
1098   Hash aModule;                 /* populated by sqlite3_create_module() */
1099   VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
1100   VTable **aVTrans;             /* Virtual tables with open transactions */
1101   VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
1102 #endif
1103   FuncDefHash aFunc;            /* Hash table of connection functions */
1104   Hash aCollSeq;                /* All collating sequences */
1105   BusyHandler busyHandler;      /* Busy callback */
1106   Db aDbStatic[2];              /* Static space for the 2 default backends */
1107   Savepoint *pSavepoint;        /* List of active savepoints */
1108   int busyTimeout;              /* Busy handler timeout, in msec */
1109   int nSavepoint;               /* Number of non-transaction savepoints */
1110   int nStatement;               /* Number of nested statement-transactions  */
1111   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
1112   i64 nDeferredImmCons;         /* Net deferred immediate constraints */
1113   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
1114 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
1115   /* The following variables are all protected by the STATIC_MASTER
1116   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
1117   **
1118   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
1119   ** unlock so that it can proceed.
1120   **
1121   ** When X.pBlockingConnection==Y, that means that something that X tried
1122   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
1123   ** held by Y.
1124   */
1125   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
1126   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
1127   void *pUnlockArg;                     /* Argument to xUnlockNotify */
1128   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
1129   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
1130 #endif
1131 #ifdef SQLITE_USER_AUTHENTICATION
1132   sqlite3_userauth auth;        /* User authentication information */
1133 #endif
1134 };
1135 
1136 /*
1137 ** A macro to discover the encoding of a database.
1138 */
1139 #define ENC(db) ((db)->aDb[0].pSchema->enc)
1140 
1141 /*
1142 ** Possible values for the sqlite3.flags.
1143 */
1144 #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
1145 #define SQLITE_InternChanges  0x00000002  /* Uncommitted Hash table changes */
1146 #define SQLITE_FullFSync      0x00000004  /* Use full fsync on the backend */
1147 #define SQLITE_CkptFullFSync  0x00000008  /* Use full fsync for checkpoint */
1148 #define SQLITE_CacheSpill     0x00000010  /* OK to spill pager cache */
1149 #define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
1150 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
1151 #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
1152                                           /*   DELETE, or UPDATE and return */
1153                                           /*   the count using a callback. */
1154 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
1155                                           /*   result set is empty */
1156 #define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
1157 #define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
1158 #define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
1159 #define SQLITE_VdbeAddopTrace 0x00001000  /* Trace sqlite3VdbeAddOp() calls */
1160 #define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
1161 #define SQLITE_ReadUncommitted 0x0004000  /* For shared-cache mode */
1162 #define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
1163 #define SQLITE_RecoveryMode   0x00010000  /* Ignore schema errors */
1164 #define SQLITE_ReverseOrder   0x00020000  /* Reverse unordered SELECTs */
1165 #define SQLITE_RecTriggers    0x00040000  /* Enable recursive triggers */
1166 #define SQLITE_ForeignKeys    0x00080000  /* Enforce foreign key constraints  */
1167 #define SQLITE_AutoIndex      0x00100000  /* Enable automatic indexes */
1168 #define SQLITE_PreferBuiltin  0x00200000  /* Preference to built-in funcs */
1169 #define SQLITE_LoadExtension  0x00400000  /* Enable load_extension */
1170 #define SQLITE_EnableTrigger  0x00800000  /* True to enable triggers */
1171 #define SQLITE_DeferFKs       0x01000000  /* Defer all FK constraints */
1172 #define SQLITE_QueryOnly      0x02000000  /* Disable database changes */
1173 #define SQLITE_VdbeEQP        0x04000000  /* Debug EXPLAIN QUERY PLAN */
1174 
1175 
1176 /*
1177 ** Bits of the sqlite3.dbOptFlags field that are used by the
1178 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
1179 ** selectively disable various optimizations.
1180 */
1181 #define SQLITE_QueryFlattener 0x0001   /* Query flattening */
1182 #define SQLITE_ColumnCache    0x0002   /* Column cache */
1183 #define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
1184 #define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
1185 /*                not used    0x0010   // Was: SQLITE_IdxRealAsInt */
1186 #define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
1187 #define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
1188 #define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
1189 #define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
1190 #define SQLITE_Transitive     0x0200   /* Transitive constraints */
1191 #define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
1192 #define SQLITE_Stat3          0x0800   /* Use the SQLITE_STAT3 table */
1193 #define SQLITE_AllOpts        0xffff   /* All optimizations */
1194 
1195 /*
1196 ** Macros for testing whether or not optimizations are enabled or disabled.
1197 */
1198 #ifndef SQLITE_OMIT_BUILTIN_TEST
1199 #define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
1200 #define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
1201 #else
1202 #define OptimizationDisabled(db, mask)  0
1203 #define OptimizationEnabled(db, mask)   1
1204 #endif
1205 
1206 /*
1207 ** Return true if it OK to factor constant expressions into the initialization
1208 ** code. The argument is a Parse object for the code generator.
1209 */
1210 #define ConstFactorOk(P) ((P)->okConstFactor)
1211 
1212 /*
1213 ** Possible values for the sqlite.magic field.
1214 ** The numbers are obtained at random and have no special meaning, other
1215 ** than being distinct from one another.
1216 */
1217 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
1218 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
1219 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
1220 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
1221 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
1222 #define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */
1223 
1224 /*
1225 ** Each SQL function is defined by an instance of the following
1226 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
1227 ** hash table.  When multiple functions have the same name, the hash table
1228 ** points to a linked list of these structures.
1229 */
1230 struct FuncDef {
1231   i16 nArg;            /* Number of arguments.  -1 means unlimited */
1232   u16 funcFlags;       /* Some combination of SQLITE_FUNC_* */
1233   void *pUserData;     /* User data parameter */
1234   FuncDef *pNext;      /* Next function with same name */
1235   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
1236   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
1237   void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
1238   char *zName;         /* SQL name of the function. */
1239   FuncDef *pHash;      /* Next with a different name but the same hash */
1240   FuncDestructor *pDestructor;   /* Reference counted destructor function */
1241 };
1242 
1243 /*
1244 ** This structure encapsulates a user-function destructor callback (as
1245 ** configured using create_function_v2()) and a reference counter. When
1246 ** create_function_v2() is called to create a function with a destructor,
1247 ** a single object of this type is allocated. FuncDestructor.nRef is set to
1248 ** the number of FuncDef objects created (either 1 or 3, depending on whether
1249 ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
1250 ** member of each of the new FuncDef objects is set to point to the allocated
1251 ** FuncDestructor.
1252 **
1253 ** Thereafter, when one of the FuncDef objects is deleted, the reference
1254 ** count on this object is decremented. When it reaches 0, the destructor
1255 ** is invoked and the FuncDestructor structure freed.
1256 */
1257 struct FuncDestructor {
1258   int nRef;
1259   void (*xDestroy)(void *);
1260   void *pUserData;
1261 };
1262 
1263 /*
1264 ** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
1265 ** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  There
1266 ** are assert() statements in the code to verify this.
1267 */
1268 #define SQLITE_FUNC_ENCMASK  0x003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
1269 #define SQLITE_FUNC_LIKE     0x004 /* Candidate for the LIKE optimization */
1270 #define SQLITE_FUNC_CASE     0x008 /* Case-sensitive LIKE-type function */
1271 #define SQLITE_FUNC_EPHEM    0x010 /* Ephemeral.  Delete with VDBE */
1272 #define SQLITE_FUNC_NEEDCOLL 0x020 /* sqlite3GetFuncCollSeq() might be called */
1273 #define SQLITE_FUNC_LENGTH   0x040 /* Built-in length() function */
1274 #define SQLITE_FUNC_TYPEOF   0x080 /* Built-in typeof() function */
1275 #define SQLITE_FUNC_COUNT    0x100 /* Built-in count(*) aggregate */
1276 #define SQLITE_FUNC_COALESCE 0x200 /* Built-in coalesce() or ifnull() */
1277 #define SQLITE_FUNC_UNLIKELY 0x400 /* Built-in unlikely() function */
1278 #define SQLITE_FUNC_CONSTANT 0x800 /* Constant inputs give a constant output */
1279 
1280 /*
1281 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
1282 ** used to create the initializers for the FuncDef structures.
1283 **
1284 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
1285 **     Used to create a scalar function definition of a function zName
1286 **     implemented by C function xFunc that accepts nArg arguments. The
1287 **     value passed as iArg is cast to a (void*) and made available
1288 **     as the user-data (sqlite3_user_data()) for the function. If
1289 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
1290 **
1291 **   VFUNCTION(zName, nArg, iArg, bNC, xFunc)
1292 **     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
1293 **
1294 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
1295 **     Used to create an aggregate function definition implemented by
1296 **     the C functions xStep and xFinal. The first four parameters
1297 **     are interpreted in the same way as the first 4 parameters to
1298 **     FUNCTION().
1299 **
1300 **   LIKEFUNC(zName, nArg, pArg, flags)
1301 **     Used to create a scalar function definition of a function zName
1302 **     that accepts nArg arguments and is implemented by a call to C
1303 **     function likeFunc. Argument pArg is cast to a (void *) and made
1304 **     available as the function user-data (sqlite3_user_data()). The
1305 **     FuncDef.flags variable is set to the value passed as the flags
1306 **     parameter.
1307 */
1308 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1309   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1310    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1311 #define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
1312   {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1313    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1314 #define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
1315   {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
1316    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1317 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
1318   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
1319    pArg, 0, xFunc, 0, 0, #zName, 0, 0}
1320 #define LIKEFUNC(zName, nArg, arg, flags) \
1321   {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
1322    (void *)arg, 0, likeFunc, 0, 0, #zName, 0, 0}
1323 #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
1324   {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
1325    SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}
1326 
1327 /*
1328 ** All current savepoints are stored in a linked list starting at
1329 ** sqlite3.pSavepoint. The first element in the list is the most recently
1330 ** opened savepoint. Savepoints are added to the list by the vdbe
1331 ** OP_Savepoint instruction.
1332 */
1333 struct Savepoint {
1334   char *zName;                        /* Savepoint name (nul-terminated) */
1335   i64 nDeferredCons;                  /* Number of deferred fk violations */
1336   i64 nDeferredImmCons;               /* Number of deferred imm fk. */
1337   Savepoint *pNext;                   /* Parent savepoint (if any) */
1338 };
1339 
1340 /*
1341 ** The following are used as the second parameter to sqlite3Savepoint(),
1342 ** and as the P1 argument to the OP_Savepoint instruction.
1343 */
1344 #define SAVEPOINT_BEGIN      0
1345 #define SAVEPOINT_RELEASE    1
1346 #define SAVEPOINT_ROLLBACK   2
1347 
1348 
1349 /*
1350 ** Each SQLite module (virtual table definition) is defined by an
1351 ** instance of the following structure, stored in the sqlite3.aModule
1352 ** hash table.
1353 */
1354 struct Module {
1355   const sqlite3_module *pModule;       /* Callback pointers */
1356   const char *zName;                   /* Name passed to create_module() */
1357   void *pAux;                          /* pAux passed to create_module() */
1358   void (*xDestroy)(void *);            /* Module destructor function */
1359 };
1360 
1361 /*
1362 ** information about each column of an SQL table is held in an instance
1363 ** of this structure.
1364 */
1365 struct Column {
1366   char *zName;     /* Name of this column */
1367   Expr *pDflt;     /* Default value of this column */
1368   char *zDflt;     /* Original text of the default value */
1369   char *zType;     /* Data type for this column */
1370   char *zColl;     /* Collating sequence.  If NULL, use the default */
1371   u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
1372   char affinity;   /* One of the SQLITE_AFF_... values */
1373   u8 szEst;        /* Estimated size of this column.  INT==1 */
1374   u8 colFlags;     /* Boolean properties.  See COLFLAG_ defines below */
1375 };
1376 
1377 /* Allowed values for Column.colFlags:
1378 */
1379 #define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
1380 #define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */
1381 
1382 /*
1383 ** A "Collating Sequence" is defined by an instance of the following
1384 ** structure. Conceptually, a collating sequence consists of a name and
1385 ** a comparison routine that defines the order of that sequence.
1386 **
1387 ** If CollSeq.xCmp is NULL, it means that the
1388 ** collating sequence is undefined.  Indices built on an undefined
1389 ** collating sequence may not be read or written.
1390 */
1391 struct CollSeq {
1392   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
1393   u8 enc;               /* Text encoding handled by xCmp() */
1394   void *pUser;          /* First argument to xCmp() */
1395   int (*xCmp)(void*,int, const void*, int, const void*);
1396   void (*xDel)(void*);  /* Destructor for pUser */
1397 };
1398 
1399 /*
1400 ** A sort order can be either ASC or DESC.
1401 */
1402 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
1403 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
1404 
1405 /*
1406 ** Column affinity types.
1407 **
1408 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
1409 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
1410 ** the speed a little by numbering the values consecutively.
1411 **
1412 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
1413 ** when multiple affinity types are concatenated into a string and
1414 ** used as the P4 operand, they will be more readable.
1415 **
1416 ** Note also that the numeric types are grouped together so that testing
1417 ** for a numeric type is a single comparison.
1418 */
1419 #define SQLITE_AFF_TEXT     'a'
1420 #define SQLITE_AFF_NONE     'b'
1421 #define SQLITE_AFF_NUMERIC  'c'
1422 #define SQLITE_AFF_INTEGER  'd'
1423 #define SQLITE_AFF_REAL     'e'
1424 
1425 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
1426 
1427 /*
1428 ** The SQLITE_AFF_MASK values masks off the significant bits of an
1429 ** affinity value.
1430 */
1431 #define SQLITE_AFF_MASK     0x67
1432 
1433 /*
1434 ** Additional bit values that can be ORed with an affinity without
1435 ** changing the affinity.
1436 **
1437 ** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
1438 ** It causes an assert() to fire if either operand to a comparison
1439 ** operator is NULL.  It is added to certain comparison operators to
1440 ** prove that the operands are always NOT NULL.
1441 */
1442 #define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
1443 #define SQLITE_STOREP2      0x10  /* Store result in reg[P2] rather than jump */
1444 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
1445 #define SQLITE_NOTNULL      0x88  /* Assert that operands are never NULL */
1446 
1447 /*
1448 ** An object of this type is created for each virtual table present in
1449 ** the database schema.
1450 **
1451 ** If the database schema is shared, then there is one instance of this
1452 ** structure for each database connection (sqlite3*) that uses the shared
1453 ** schema. This is because each database connection requires its own unique
1454 ** instance of the sqlite3_vtab* handle used to access the virtual table
1455 ** implementation. sqlite3_vtab* handles can not be shared between
1456 ** database connections, even when the rest of the in-memory database
1457 ** schema is shared, as the implementation often stores the database
1458 ** connection handle passed to it via the xConnect() or xCreate() method
1459 ** during initialization internally. This database connection handle may
1460 ** then be used by the virtual table implementation to access real tables
1461 ** within the database. So that they appear as part of the callers
1462 ** transaction, these accesses need to be made via the same database
1463 ** connection as that used to execute SQL operations on the virtual table.
1464 **
1465 ** All VTable objects that correspond to a single table in a shared
1466 ** database schema are initially stored in a linked-list pointed to by
1467 ** the Table.pVTable member variable of the corresponding Table object.
1468 ** When an sqlite3_prepare() operation is required to access the virtual
1469 ** table, it searches the list for the VTable that corresponds to the
1470 ** database connection doing the preparing so as to use the correct
1471 ** sqlite3_vtab* handle in the compiled query.
1472 **
1473 ** When an in-memory Table object is deleted (for example when the
1474 ** schema is being reloaded for some reason), the VTable objects are not
1475 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
1476 ** immediately. Instead, they are moved from the Table.pVTable list to
1477 ** another linked list headed by the sqlite3.pDisconnect member of the
1478 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
1479 ** next time a statement is prepared using said sqlite3*. This is done
1480 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
1481 ** Refer to comments above function sqlite3VtabUnlockList() for an
1482 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
1483 ** list without holding the corresponding sqlite3.mutex mutex.
1484 **
1485 ** The memory for objects of this type is always allocated by
1486 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
1487 ** the first argument.
1488 */
1489 struct VTable {
1490   sqlite3 *db;              /* Database connection associated with this table */
1491   Module *pMod;             /* Pointer to module implementation */
1492   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
1493   int nRef;                 /* Number of pointers to this structure */
1494   u8 bConstraint;           /* True if constraints are supported */
1495   int iSavepoint;           /* Depth of the SAVEPOINT stack */
1496   VTable *pNext;            /* Next in linked list (see above) */
1497 };
1498 
1499 /*
1500 ** Each SQL table is represented in memory by an instance of the
1501 ** following structure.
1502 **
1503 ** Table.zName is the name of the table.  The case of the original
1504 ** CREATE TABLE statement is stored, but case is not significant for
1505 ** comparisons.
1506 **
1507 ** Table.nCol is the number of columns in this table.  Table.aCol is a
1508 ** pointer to an array of Column structures, one for each column.
1509 **
1510 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
1511 ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
1512 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
1513 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
1514 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
1515 ** is generated for each row of the table.  TF_HasPrimaryKey is set if
1516 ** the table has any PRIMARY KEY, INTEGER or otherwise.
1517 **
1518 ** Table.tnum is the page number for the root BTree page of the table in the
1519 ** database file.  If Table.iDb is the index of the database table backend
1520 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
1521 ** holds temporary tables and indices.  If TF_Ephemeral is set
1522 ** then the table is stored in a file that is automatically deleted
1523 ** when the VDBE cursor to the table is closed.  In this case Table.tnum
1524 ** refers VDBE cursor number that holds the table open, not to the root
1525 ** page number.  Transient tables are used to hold the results of a
1526 ** sub-query that appears instead of a real table name in the FROM clause
1527 ** of a SELECT statement.
1528 */
1529 struct Table {
1530   char *zName;         /* Name of the table or view */
1531   Column *aCol;        /* Information about each column */
1532   Index *pIndex;       /* List of SQL indexes on this table. */
1533   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
1534   FKey *pFKey;         /* Linked list of all foreign keys in this table */
1535   char *zColAff;       /* String defining the affinity of each column */
1536 #ifndef SQLITE_OMIT_CHECK
1537   ExprList *pCheck;    /* All CHECK constraints */
1538 #endif
1539   LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
1540   int tnum;            /* Root BTree node for this table (see note above) */
1541   i16 iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
1542   i16 nCol;            /* Number of columns in this table */
1543   u16 nRef;            /* Number of pointers to this Table */
1544   LogEst szTabRow;     /* Estimated size of each table row in bytes */
1545 #ifdef SQLITE_ENABLE_COSTMULT
1546   LogEst costMult;     /* Cost multiplier for using this table */
1547 #endif
1548   u8 tabFlags;         /* Mask of TF_* values */
1549   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
1550 #ifndef SQLITE_OMIT_ALTERTABLE
1551   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
1552 #endif
1553 #ifndef SQLITE_OMIT_VIRTUALTABLE
1554   int nModuleArg;      /* Number of arguments to the module */
1555   char **azModuleArg;  /* Text of all module args. [0] is module name */
1556   VTable *pVTable;     /* List of VTable objects. */
1557 #endif
1558   Trigger *pTrigger;   /* List of triggers stored in pSchema */
1559   Schema *pSchema;     /* Schema that contains this table */
1560   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
1561 };
1562 
1563 /*
1564 ** Allowed values for Table.tabFlags.
1565 */
1566 #define TF_Readonly        0x01    /* Read-only system table */
1567 #define TF_Ephemeral       0x02    /* An ephemeral table */
1568 #define TF_HasPrimaryKey   0x04    /* Table has a primary key */
1569 #define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
1570 #define TF_Virtual         0x10    /* Is a virtual table */
1571 #define TF_WithoutRowid    0x20    /* No rowid used. PRIMARY KEY is the key */
1572 
1573 
1574 /*
1575 ** Test to see whether or not a table is a virtual table.  This is
1576 ** done as a macro so that it will be optimized out when virtual
1577 ** table support is omitted from the build.
1578 */
1579 #ifndef SQLITE_OMIT_VIRTUALTABLE
1580 #  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
1581 #  define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1582 #else
1583 #  define IsVirtual(X)      0
1584 #  define IsHiddenColumn(X) 0
1585 #endif
1586 
1587 /* Does the table have a rowid */
1588 #define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
1589 
1590 /*
1591 ** Each foreign key constraint is an instance of the following structure.
1592 **
1593 ** A foreign key is associated with two tables.  The "from" table is
1594 ** the table that contains the REFERENCES clause that creates the foreign
1595 ** key.  The "to" table is the table that is named in the REFERENCES clause.
1596 ** Consider this example:
1597 **
1598 **     CREATE TABLE ex1(
1599 **       a INTEGER PRIMARY KEY,
1600 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
1601 **     );
1602 **
1603 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
1604 ** Equivalent names:
1605 **
1606 **     from-table == child-table
1607 **       to-table == parent-table
1608 **
1609 ** Each REFERENCES clause generates an instance of the following structure
1610 ** which is attached to the from-table.  The to-table need not exist when
1611 ** the from-table is created.  The existence of the to-table is not checked.
1612 **
1613 ** The list of all parents for child Table X is held at X.pFKey.
1614 **
1615 ** A list of all children for a table named Z (which might not even exist)
1616 ** is held in Schema.fkeyHash with a hash key of Z.
1617 */
1618 struct FKey {
1619   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
1620   FKey *pNextFrom;  /* Next FKey with the same in pFrom. Next parent of pFrom */
1621   char *zTo;        /* Name of table that the key points to (aka: Parent) */
1622   FKey *pNextTo;    /* Next with the same zTo. Next child of zTo. */
1623   FKey *pPrevTo;    /* Previous with the same zTo */
1624   int nCol;         /* Number of columns in this key */
1625   /* EV: R-30323-21917 */
1626   u8 isDeferred;       /* True if constraint checking is deferred till COMMIT */
1627   u8 aAction[2];        /* ON DELETE and ON UPDATE actions, respectively */
1628   Trigger *apTrigger[2];/* Triggers for aAction[] actions */
1629   struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
1630     int iFrom;            /* Index of column in pFrom */
1631     char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
1632   } aCol[1];            /* One entry for each of nCol columns */
1633 };
1634 
1635 /*
1636 ** SQLite supports many different ways to resolve a constraint
1637 ** error.  ROLLBACK processing means that a constraint violation
1638 ** causes the operation in process to fail and for the current transaction
1639 ** to be rolled back.  ABORT processing means the operation in process
1640 ** fails and any prior changes from that one operation are backed out,
1641 ** but the transaction is not rolled back.  FAIL processing means that
1642 ** the operation in progress stops and returns an error code.  But prior
1643 ** changes due to the same operation are not backed out and no rollback
1644 ** occurs.  IGNORE means that the particular row that caused the constraint
1645 ** error is not inserted or updated.  Processing continues and no error
1646 ** is returned.  REPLACE means that preexisting database rows that caused
1647 ** a UNIQUE constraint violation are removed so that the new insert or
1648 ** update can proceed.  Processing continues and no error is reported.
1649 **
1650 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
1651 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
1652 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
1653 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
1654 ** referenced table row is propagated into the row that holds the
1655 ** foreign key.
1656 **
1657 ** The following symbolic values are used to record which type
1658 ** of action to take.
1659 */
1660 #define OE_None     0   /* There is no constraint to check */
1661 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
1662 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
1663 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
1664 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
1665 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
1666 
1667 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
1668 #define OE_SetNull  7   /* Set the foreign key value to NULL */
1669 #define OE_SetDflt  8   /* Set the foreign key value to its default */
1670 #define OE_Cascade  9   /* Cascade the changes */
1671 
1672 #define OE_Default  10  /* Do whatever the default action is */
1673 
1674 
1675 /*
1676 ** An instance of the following structure is passed as the first
1677 ** argument to sqlite3VdbeKeyCompare and is used to control the
1678 ** comparison of the two index keys.
1679 **
1680 ** Note that aSortOrder[] and aColl[] have nField+1 slots.  There
1681 ** are nField slots for the columns of an index then one extra slot
1682 ** for the rowid at the end.
1683 */
1684 struct KeyInfo {
1685   u32 nRef;           /* Number of references to this KeyInfo object */
1686   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
1687   u16 nField;         /* Number of key columns in the index */
1688   u16 nXField;        /* Number of columns beyond the key columns */
1689   sqlite3 *db;        /* The database connection */
1690   u8 *aSortOrder;     /* Sort order for each column. */
1691   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
1692 };
1693 
1694 /*
1695 ** An instance of the following structure holds information about a
1696 ** single index record that has already been parsed out into individual
1697 ** values.
1698 **
1699 ** A record is an object that contains one or more fields of data.
1700 ** Records are used to store the content of a table row and to store
1701 ** the key of an index.  A blob encoding of a record is created by
1702 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
1703 ** OP_Column opcode.
1704 **
1705 ** This structure holds a record that has already been disassembled
1706 ** into its constituent fields.
1707 **
1708 ** The r1 and r2 member variables are only used by the optimized comparison
1709 ** functions vdbeRecordCompareInt() and vdbeRecordCompareString().
1710 */
1711 struct UnpackedRecord {
1712   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
1713   u16 nField;         /* Number of entries in apMem[] */
1714   i8 default_rc;      /* Comparison result if keys are equal */
1715   u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
1716   Mem *aMem;          /* Values */
1717   int r1;             /* Value to return if (lhs > rhs) */
1718   int r2;             /* Value to return if (rhs < lhs) */
1719 };
1720 
1721 
1722 /*
1723 ** Each SQL index is represented in memory by an
1724 ** instance of the following structure.
1725 **
1726 ** The columns of the table that are to be indexed are described
1727 ** by the aiColumn[] field of this structure.  For example, suppose
1728 ** we have the following table and index:
1729 **
1730 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
1731 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
1732 **
1733 ** In the Table structure describing Ex1, nCol==3 because there are
1734 ** three columns in the table.  In the Index structure describing
1735 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
1736 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
1737 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
1738 ** The second column to be indexed (c1) has an index of 0 in
1739 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
1740 **
1741 ** The Index.onError field determines whether or not the indexed columns
1742 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
1743 ** it means this is not a unique index.  Otherwise it is a unique index
1744 ** and the value of Index.onError indicate the which conflict resolution
1745 ** algorithm to employ whenever an attempt is made to insert a non-unique
1746 ** element.
1747 */
1748 struct Index {
1749   char *zName;             /* Name of this index */
1750   i16 *aiColumn;           /* Which columns are used by this index.  1st is 0 */
1751   LogEst *aiRowLogEst;     /* From ANALYZE: Est. rows selected by each column */
1752   Table *pTable;           /* The SQL table being indexed */
1753   char *zColAff;           /* String defining the affinity of each column */
1754   Index *pNext;            /* The next index associated with the same table */
1755   Schema *pSchema;         /* Schema containing this index */
1756   u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
1757   char **azColl;           /* Array of collation sequence names for index */
1758   Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
1759   KeyInfo *pKeyInfo;       /* A KeyInfo object suitable for this index */
1760   int tnum;                /* DB Page containing root of this index */
1761   LogEst szIdxRow;         /* Estimated average row size in bytes */
1762   u16 nKeyCol;             /* Number of columns forming the key */
1763   u16 nColumn;             /* Number of columns stored in the index */
1764   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
1765   unsigned idxType:2;      /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
1766   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
1767   unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
1768   unsigned isResized:1;    /* True if resizeIndexObject() has been called */
1769   unsigned isCovering:1;   /* True if this is a covering index */
1770 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
1771   int nSample;             /* Number of elements in aSample[] */
1772   int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
1773   tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
1774   IndexSample *aSample;    /* Samples of the left-most key */
1775 #endif
1776 };
1777 
1778 /*
1779 ** Allowed values for Index.idxType
1780 */
1781 #define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
1782 #define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */
1783 #define SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */
1784 
1785 /* Return true if index X is a PRIMARY KEY index */
1786 #define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
1787 
1788 /* Return true if index X is a UNIQUE index */
1789 #define IsUniqueIndex(X)      ((X)->onError!=OE_None)
1790 
1791 /*
1792 ** Each sample stored in the sqlite_stat3 table is represented in memory
1793 ** using a structure of this type.  See documentation at the top of the
1794 ** analyze.c source file for additional information.
1795 */
1796 struct IndexSample {
1797   void *p;          /* Pointer to sampled record */
1798   int n;            /* Size of record in bytes */
1799   tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
1800   tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
1801   tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
1802 };
1803 
1804 /*
1805 ** Each token coming out of the lexer is an instance of
1806 ** this structure.  Tokens are also used as part of an expression.
1807 **
1808 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
1809 ** may contain random values.  Do not make any assumptions about Token.dyn
1810 ** and Token.n when Token.z==0.
1811 */
1812 struct Token {
1813   const char *z;     /* Text of the token.  Not NULL-terminated! */
1814   unsigned int n;    /* Number of characters in this token */
1815 };
1816 
1817 /*
1818 ** An instance of this structure contains information needed to generate
1819 ** code for a SELECT that contains aggregate functions.
1820 **
1821 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
1822 ** pointer to this structure.  The Expr.iColumn field is the index in
1823 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
1824 ** code for that node.
1825 **
1826 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
1827 ** original Select structure that describes the SELECT statement.  These
1828 ** fields do not need to be freed when deallocating the AggInfo structure.
1829 */
1830 struct AggInfo {
1831   u8 directMode;          /* Direct rendering mode means take data directly
1832                           ** from source tables rather than from accumulators */
1833   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
1834                           ** than the source table */
1835   int sortingIdx;         /* Cursor number of the sorting index */
1836   int sortingIdxPTab;     /* Cursor number of pseudo-table */
1837   int nSortingColumn;     /* Number of columns in the sorting index */
1838   int mnReg, mxReg;       /* Range of registers allocated for aCol and aFunc */
1839   ExprList *pGroupBy;     /* The group by clause */
1840   struct AggInfo_col {    /* For each column used in source tables */
1841     Table *pTab;             /* Source table */
1842     int iTable;              /* Cursor number of the source table */
1843     int iColumn;             /* Column number within the source table */
1844     int iSorterColumn;       /* Column number in the sorting index */
1845     int iMem;                /* Memory location that acts as accumulator */
1846     Expr *pExpr;             /* The original expression */
1847   } *aCol;
1848   int nColumn;            /* Number of used entries in aCol[] */
1849   int nAccumulator;       /* Number of columns that show through to the output.
1850                           ** Additional columns are used only as parameters to
1851                           ** aggregate functions */
1852   struct AggInfo_func {   /* For each aggregate function */
1853     Expr *pExpr;             /* Expression encoding the function */
1854     FuncDef *pFunc;          /* The aggregate function implementation */
1855     int iMem;                /* Memory location that acts as accumulator */
1856     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
1857   } *aFunc;
1858   int nFunc;              /* Number of entries in aFunc[] */
1859 };
1860 
1861 /*
1862 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
1863 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
1864 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
1865 ** it uses less memory in the Expr object, which is a big memory user
1866 ** in systems with lots of prepared statements.  And few applications
1867 ** need more than about 10 or 20 variables.  But some extreme users want
1868 ** to have prepared statements with over 32767 variables, and for them
1869 ** the option is available (at compile-time).
1870 */
1871 #if SQLITE_MAX_VARIABLE_NUMBER<=32767
1872 typedef i16 ynVar;
1873 #else
1874 typedef int ynVar;
1875 #endif
1876 
1877 /*
1878 ** Each node of an expression in the parse tree is an instance
1879 ** of this structure.
1880 **
1881 ** Expr.op is the opcode. The integer parser token codes are reused
1882 ** as opcodes here. For example, the parser defines TK_GE to be an integer
1883 ** code representing the ">=" operator. This same integer code is reused
1884 ** to represent the greater-than-or-equal-to operator in the expression
1885 ** tree.
1886 **
1887 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
1888 ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
1889 ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
1890 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
1891 ** then Expr.token contains the name of the function.
1892 **
1893 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
1894 ** binary operator. Either or both may be NULL.
1895 **
1896 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
1897 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
1898 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
1899 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
1900 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
1901 ** valid.
1902 **
1903 ** An expression of the form ID or ID.ID refers to a column in a table.
1904 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
1905 ** the integer cursor number of a VDBE cursor pointing to that table and
1906 ** Expr.iColumn is the column number for the specific column.  If the
1907 ** expression is used as a result in an aggregate SELECT, then the
1908 ** value is also stored in the Expr.iAgg column in the aggregate so that
1909 ** it can be accessed after all aggregates are computed.
1910 **
1911 ** If the expression is an unbound variable marker (a question mark
1912 ** character '?' in the original SQL) then the Expr.iTable holds the index
1913 ** number for that variable.
1914 **
1915 ** If the expression is a subquery then Expr.iColumn holds an integer
1916 ** register number containing the result of the subquery.  If the
1917 ** subquery gives a constant result, then iTable is -1.  If the subquery
1918 ** gives a different answer at different times during statement processing
1919 ** then iTable is the address of a subroutine that computes the subquery.
1920 **
1921 ** If the Expr is of type OP_Column, and the table it is selecting from
1922 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
1923 ** corresponding table definition.
1924 **
1925 ** ALLOCATION NOTES:
1926 **
1927 ** Expr objects can use a lot of memory space in database schema.  To
1928 ** help reduce memory requirements, sometimes an Expr object will be
1929 ** truncated.  And to reduce the number of memory allocations, sometimes
1930 ** two or more Expr objects will be stored in a single memory allocation,
1931 ** together with Expr.zToken strings.
1932 **
1933 ** If the EP_Reduced and EP_TokenOnly flags are set when
1934 ** an Expr object is truncated.  When EP_Reduced is set, then all
1935 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
1936 ** are contained within the same memory allocation.  Note, however, that
1937 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
1938 ** allocated, regardless of whether or not EP_Reduced is set.
1939 */
1940 struct Expr {
1941   u8 op;                 /* Operation performed by this node */
1942   char affinity;         /* The affinity of the column or 0 if not a column */
1943   u32 flags;             /* Various flags.  EP_* See below */
1944   union {
1945     char *zToken;          /* Token value. Zero terminated and dequoted */
1946     int iValue;            /* Non-negative integer value if EP_IntValue */
1947   } u;
1948 
1949   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
1950   ** space is allocated for the fields below this point. An attempt to
1951   ** access them will result in a segfault or malfunction.
1952   *********************************************************************/
1953 
1954   Expr *pLeft;           /* Left subnode */
1955   Expr *pRight;          /* Right subnode */
1956   union {
1957     ExprList *pList;     /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
1958     Select *pSelect;     /* EP_xIsSelect and op = IN, EXISTS, SELECT */
1959   } x;
1960 
1961   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
1962   ** space is allocated for the fields below this point. An attempt to
1963   ** access them will result in a segfault or malfunction.
1964   *********************************************************************/
1965 
1966 #if SQLITE_MAX_EXPR_DEPTH>0
1967   int nHeight;           /* Height of the tree headed by this node */
1968 #endif
1969   int iTable;            /* TK_COLUMN: cursor number of table holding column
1970                          ** TK_REGISTER: register number
1971                          ** TK_TRIGGER: 1 -> new, 0 -> old
1972                          ** EP_Unlikely:  1000 times likelihood */
1973   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
1974                          ** TK_VARIABLE: variable number (always >= 1). */
1975   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
1976   i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
1977   u8 op2;                /* TK_REGISTER: original value of Expr.op
1978                          ** TK_COLUMN: the value of p5 for OP_Column
1979                          ** TK_AGG_FUNCTION: nesting depth */
1980   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
1981   Table *pTab;           /* Table for TK_COLUMN expressions. */
1982 };
1983 
1984 /*
1985 ** The following are the meanings of bits in the Expr.flags field.
1986 */
1987 #define EP_FromJoin  0x000001 /* Originated in ON or USING clause of a join */
1988 #define EP_Agg       0x000002 /* Contains one or more aggregate functions */
1989 #define EP_Resolved  0x000004 /* IDs have been resolved to COLUMNs */
1990 #define EP_Error     0x000008 /* Expression contains one or more errors */
1991 #define EP_Distinct  0x000010 /* Aggregate function with DISTINCT keyword */
1992 #define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
1993 #define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
1994 #define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
1995 #define EP_Collate   0x000100 /* Tree contains a TK_COLLATE operator */
1996 #define EP_Generic   0x000200 /* Ignore COLLATE or affinity on this tree */
1997 #define EP_IntValue  0x000400 /* Integer value contained in u.iValue */
1998 #define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
1999 #define EP_Skip      0x001000 /* COLLATE, AS, or UNLIKELY */
2000 #define EP_Reduced   0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
2001 #define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
2002 #define EP_Static    0x008000 /* Held in memory not obtained from malloc() */
2003 #define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
2004 #define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
2005 #define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
2006 #define EP_Constant  0x080000 /* Node is a constant */
2007 
2008 /*
2009 ** These macros can be used to test, set, or clear bits in the
2010 ** Expr.flags field.
2011 */
2012 #define ExprHasProperty(E,P)     (((E)->flags&(P))!=0)
2013 #define ExprHasAllProperty(E,P)  (((E)->flags&(P))==(P))
2014 #define ExprSetProperty(E,P)     (E)->flags|=(P)
2015 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
2016 
2017 /* The ExprSetVVAProperty() macro is used for Verification, Validation,
2018 ** and Accreditation only.  It works like ExprSetProperty() during VVA
2019 ** processes but is a no-op for delivery.
2020 */
2021 #ifdef SQLITE_DEBUG
2022 # define ExprSetVVAProperty(E,P)  (E)->flags|=(P)
2023 #else
2024 # define ExprSetVVAProperty(E,P)
2025 #endif
2026 
2027 /*
2028 ** Macros to determine the number of bytes required by a normal Expr
2029 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
2030 ** and an Expr struct with the EP_TokenOnly flag set.
2031 */
2032 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
2033 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
2034 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
2035 
2036 /*
2037 ** Flags passed to the sqlite3ExprDup() function. See the header comment
2038 ** above sqlite3ExprDup() for details.
2039 */
2040 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
2041 
2042 /*
2043 ** A list of expressions.  Each expression may optionally have a
2044 ** name.  An expr/name combination can be used in several ways, such
2045 ** as the list of "expr AS ID" fields following a "SELECT" or in the
2046 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
2047 ** also be used as the argument to a function, in which case the a.zName
2048 ** field is not used.
2049 **
2050 ** By default the Expr.zSpan field holds a human-readable description of
2051 ** the expression that is used in the generation of error messages and
2052 ** column labels.  In this case, Expr.zSpan is typically the text of a
2053 ** column expression as it exists in a SELECT statement.  However, if
2054 ** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
2055 ** of the result column in the form: DATABASE.TABLE.COLUMN.  This later
2056 ** form is used for name resolution with nested FROM clauses.
2057 */
2058 struct ExprList {
2059   int nExpr;             /* Number of expressions on the list */
2060   struct ExprList_item { /* For each expression in the list */
2061     Expr *pExpr;            /* The list of expressions */
2062     char *zName;            /* Token associated with this expression */
2063     char *zSpan;            /* Original text of the expression */
2064     u8 sortOrder;           /* 1 for DESC or 0 for ASC */
2065     unsigned done :1;       /* A flag to indicate when processing is finished */
2066     unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
2067     unsigned reusable :1;   /* Constant expression is reusable */
2068     union {
2069       struct {
2070         u16 iOrderByCol;      /* For ORDER BY, column number in result set */
2071         u16 iAlias;           /* Index into Parse.aAlias[] for zName */
2072       } x;
2073       int iConstExprReg;      /* Register in which Expr value is cached */
2074     } u;
2075   } *a;                  /* Alloc a power of two greater or equal to nExpr */
2076 };
2077 
2078 /*
2079 ** An instance of this structure is used by the parser to record both
2080 ** the parse tree for an expression and the span of input text for an
2081 ** expression.
2082 */
2083 struct ExprSpan {
2084   Expr *pExpr;          /* The expression parse tree */
2085   const char *zStart;   /* First character of input text */
2086   const char *zEnd;     /* One character past the end of input text */
2087 };
2088 
2089 /*
2090 ** An instance of this structure can hold a simple list of identifiers,
2091 ** such as the list "a,b,c" in the following statements:
2092 **
2093 **      INSERT INTO t(a,b,c) VALUES ...;
2094 **      CREATE INDEX idx ON t(a,b,c);
2095 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
2096 **
2097 ** The IdList.a.idx field is used when the IdList represents the list of
2098 ** column names after a table name in an INSERT statement.  In the statement
2099 **
2100 **     INSERT INTO t(a,b,c) ...
2101 **
2102 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
2103 */
2104 struct IdList {
2105   struct IdList_item {
2106     char *zName;      /* Name of the identifier */
2107     int idx;          /* Index in some Table.aCol[] of a column named zName */
2108   } *a;
2109   int nId;         /* Number of identifiers on the list */
2110 };
2111 
2112 /*
2113 ** The bitmask datatype defined below is used for various optimizations.
2114 **
2115 ** Changing this from a 64-bit to a 32-bit type limits the number of
2116 ** tables in a join to 32 instead of 64.  But it also reduces the size
2117 ** of the library by 738 bytes on ix86.
2118 */
2119 typedef u64 Bitmask;
2120 
2121 /*
2122 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
2123 */
2124 #define BMS  ((int)(sizeof(Bitmask)*8))
2125 
2126 /*
2127 ** A bit in a Bitmask
2128 */
2129 #define MASKBIT(n)   (((Bitmask)1)<<(n))
2130 #define MASKBIT32(n) (((unsigned int)1)<<(n))
2131 
2132 /*
2133 ** The following structure describes the FROM clause of a SELECT statement.
2134 ** Each table or subquery in the FROM clause is a separate element of
2135 ** the SrcList.a[] array.
2136 **
2137 ** With the addition of multiple database support, the following structure
2138 ** can also be used to describe a particular table such as the table that
2139 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
2140 ** such a table must be a simple name: ID.  But in SQLite, the table can
2141 ** now be identified by a database name, a dot, then the table name: ID.ID.
2142 **
2143 ** The jointype starts out showing the join type between the current table
2144 ** and the next table on the list.  The parser builds the list this way.
2145 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
2146 ** jointype expresses the join between the table and the previous table.
2147 **
2148 ** In the colUsed field, the high-order bit (bit 63) is set if the table
2149 ** contains more than 63 columns and the 64-th or later column is used.
2150 */
2151 struct SrcList {
2152   int nSrc;        /* Number of tables or subqueries in the FROM clause */
2153   u32 nAlloc;      /* Number of entries allocated in a[] below */
2154   struct SrcList_item {
2155     Schema *pSchema;  /* Schema to which this item is fixed */
2156     char *zDatabase;  /* Name of database holding this table */
2157     char *zName;      /* Name of the table */
2158     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
2159     Table *pTab;      /* An SQL table corresponding to zName */
2160     Select *pSelect;  /* A SELECT statement used in place of a table name */
2161     int addrFillSub;  /* Address of subroutine to manifest a subquery */
2162     int regReturn;    /* Register holding return address of addrFillSub */
2163     int regResult;    /* Registers holding results of a co-routine */
2164     u8 jointype;      /* Type of join between this able and the previous */
2165     unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
2166     unsigned isCorrelated :1;  /* True if sub-query is correlated */
2167     unsigned viaCoroutine :1;  /* Implemented as a co-routine */
2168     unsigned isRecursive :1;   /* True for recursive reference in WITH */
2169 #ifndef SQLITE_OMIT_EXPLAIN
2170     u8 iSelectId;     /* If pSelect!=0, the id of the sub-select in EQP */
2171 #endif
2172     int iCursor;      /* The VDBE cursor number used to access this table */
2173     Expr *pOn;        /* The ON clause of a join */
2174     IdList *pUsing;   /* The USING clause of a join */
2175     Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
2176     char *zIndex;     /* Identifier from "INDEXED BY <zIndex>" clause */
2177     Index *pIndex;    /* Index structure corresponding to zIndex, if any */
2178   } a[1];             /* One entry for each identifier on the list */
2179 };
2180 
2181 /*
2182 ** Permitted values of the SrcList.a.jointype field
2183 */
2184 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
2185 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
2186 #define JT_NATURAL   0x0004    /* True for a "natural" join */
2187 #define JT_LEFT      0x0008    /* Left outer join */
2188 #define JT_RIGHT     0x0010    /* Right outer join */
2189 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
2190 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
2191 
2192 
2193 /*
2194 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
2195 ** and the WhereInfo.wctrlFlags member.
2196 */
2197 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
2198 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
2199 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
2200 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
2201 #define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
2202 #define WHERE_OMIT_OPEN_CLOSE  0x0010 /* Table cursors are already open */
2203 #define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
2204 #define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
2205 #define WHERE_AND_ONLY         0x0080 /* Don't use indices for OR terms */
2206 #define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
2207 #define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
2208 #define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
2209 #define WHERE_SORTBYGROUP      0x0800 /* Support sqlite3WhereIsSorted() */
2210 #define WHERE_REOPEN_IDX       0x1000 /* Try to use OP_ReopenIdx */
2211 
2212 /* Allowed return values from sqlite3WhereIsDistinct()
2213 */
2214 #define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
2215 #define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
2216 #define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
2217 #define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
2218 
2219 /*
2220 ** A NameContext defines a context in which to resolve table and column
2221 ** names.  The context consists of a list of tables (the pSrcList) field and
2222 ** a list of named expression (pEList).  The named expression list may
2223 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
2224 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
2225 ** pEList corresponds to the result set of a SELECT and is NULL for
2226 ** other statements.
2227 **
2228 ** NameContexts can be nested.  When resolving names, the inner-most
2229 ** context is searched first.  If no match is found, the next outer
2230 ** context is checked.  If there is still no match, the next context
2231 ** is checked.  This process continues until either a match is found
2232 ** or all contexts are check.  When a match is found, the nRef member of
2233 ** the context containing the match is incremented.
2234 **
2235 ** Each subquery gets a new NameContext.  The pNext field points to the
2236 ** NameContext in the parent query.  Thus the process of scanning the
2237 ** NameContext list corresponds to searching through successively outer
2238 ** subqueries looking for a match.
2239 */
2240 struct NameContext {
2241   Parse *pParse;       /* The parser */
2242   SrcList *pSrcList;   /* One or more tables used to resolve names */
2243   ExprList *pEList;    /* Optional list of result-set columns */
2244   AggInfo *pAggInfo;   /* Information about aggregates at this level */
2245   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
2246   int nRef;            /* Number of names resolved by this context */
2247   int nErr;            /* Number of errors encountered while resolving names */
2248   u8 ncFlags;          /* Zero or more NC_* flags defined below */
2249 };
2250 
2251 /*
2252 ** Allowed values for the NameContext, ncFlags field.
2253 */
2254 #define NC_AllowAgg  0x01    /* Aggregate functions are allowed here */
2255 #define NC_HasAgg    0x02    /* One or more aggregate functions seen */
2256 #define NC_IsCheck   0x04    /* True if resolving names in a CHECK constraint */
2257 #define NC_InAggFunc 0x08    /* True if analyzing arguments to an agg func */
2258 #define NC_PartIdx   0x10    /* True if resolving a partial index WHERE */
2259 
2260 /*
2261 ** An instance of the following structure contains all information
2262 ** needed to generate code for a single SELECT statement.
2263 **
2264 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
2265 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
2266 ** limit and nOffset to the value of the offset (or 0 if there is not
2267 ** offset).  But later on, nLimit and nOffset become the memory locations
2268 ** in the VDBE that record the limit and offset counters.
2269 **
2270 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
2271 ** These addresses must be stored so that we can go back and fill in
2272 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
2273 ** the number of columns in P2 can be computed at the same time
2274 ** as the OP_OpenEphm instruction is coded because not
2275 ** enough information about the compound query is known at that point.
2276 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
2277 ** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
2278 ** sequences for the ORDER BY clause.
2279 */
2280 struct Select {
2281   ExprList *pEList;      /* The fields of the result */
2282   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
2283   u16 selFlags;          /* Various SF_* values */
2284   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
2285   int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
2286   u64 nSelectRow;        /* Estimated number of result rows */
2287   SrcList *pSrc;         /* The FROM clause */
2288   Expr *pWhere;          /* The WHERE clause */
2289   ExprList *pGroupBy;    /* The GROUP BY clause */
2290   Expr *pHaving;         /* The HAVING clause */
2291   ExprList *pOrderBy;    /* The ORDER BY clause */
2292   Select *pPrior;        /* Prior select in a compound select statement */
2293   Select *pNext;         /* Next select to the left in a compound */
2294   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
2295   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
2296   With *pWith;           /* WITH clause attached to this select. Or NULL. */
2297 };
2298 
2299 /*
2300 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
2301 ** "Select Flag".
2302 */
2303 #define SF_Distinct        0x0001  /* Output should be DISTINCT */
2304 #define SF_Resolved        0x0002  /* Identifiers have been resolved */
2305 #define SF_Aggregate       0x0004  /* Contains aggregate functions */
2306 #define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
2307 #define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
2308 #define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
2309                     /*     0x0040  NOT USED */
2310 #define SF_Values          0x0080  /* Synthesized from VALUES clause */
2311                     /*     0x0100  NOT USED */
2312 #define SF_NestedFrom      0x0200  /* Part of a parenthesized FROM clause */
2313 #define SF_MaybeConvert    0x0400  /* Need convertCompoundSelectToSubquery() */
2314 #define SF_Recursive       0x0800  /* The recursive part of a recursive CTE */
2315 #define SF_Compound        0x1000  /* Part of a compound query */
2316 
2317 
2318 /*
2319 ** The results of a SELECT can be distributed in several ways, as defined
2320 ** by one of the following macros.  The "SRT" prefix means "SELECT Result
2321 ** Type".
2322 **
2323 **     SRT_Union       Store results as a key in a temporary index
2324 **                     identified by pDest->iSDParm.
2325 **
2326 **     SRT_Except      Remove results from the temporary index pDest->iSDParm.
2327 **
2328 **     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
2329 **                     set is not empty.
2330 **
2331 **     SRT_Discard     Throw the results away.  This is used by SELECT
2332 **                     statements within triggers whose only purpose is
2333 **                     the side-effects of functions.
2334 **
2335 ** All of the above are free to ignore their ORDER BY clause. Those that
2336 ** follow must honor the ORDER BY clause.
2337 **
2338 **     SRT_Output      Generate a row of output (using the OP_ResultRow
2339 **                     opcode) for each row in the result set.
2340 **
2341 **     SRT_Mem         Only valid if the result is a single column.
2342 **                     Store the first column of the first result row
2343 **                     in register pDest->iSDParm then abandon the rest
2344 **                     of the query.  This destination implies "LIMIT 1".
2345 **
2346 **     SRT_Set         The result must be a single column.  Store each
2347 **                     row of result as the key in table pDest->iSDParm.
2348 **                     Apply the affinity pDest->affSdst before storing
2349 **                     results.  Used to implement "IN (SELECT ...)".
2350 **
2351 **     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
2352 **                     the result there. The cursor is left open after
2353 **                     returning.  This is like SRT_Table except that
2354 **                     this destination uses OP_OpenEphemeral to create
2355 **                     the table first.
2356 **
2357 **     SRT_Coroutine   Generate a co-routine that returns a new row of
2358 **                     results each time it is invoked.  The entry point
2359 **                     of the co-routine is stored in register pDest->iSDParm
2360 **                     and the result row is stored in pDest->nDest registers
2361 **                     starting with pDest->iSdst.
2362 **
2363 **     SRT_Table       Store results in temporary table pDest->iSDParm.
2364 **     SRT_Fifo        This is like SRT_EphemTab except that the table
2365 **                     is assumed to already be open.  SRT_Fifo has
2366 **                     the additional property of being able to ignore
2367 **                     the ORDER BY clause.
2368 **
2369 **     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
2370 **                     But also use temporary table pDest->iSDParm+1 as
2371 **                     a record of all prior results and ignore any duplicate
2372 **                     rows.  Name means:  "Distinct Fifo".
2373 **
2374 **     SRT_Queue       Store results in priority queue pDest->iSDParm (really
2375 **                     an index).  Append a sequence number so that all entries
2376 **                     are distinct.
2377 **
2378 **     SRT_DistQueue   Store results in priority queue pDest->iSDParm only if
2379 **                     the same record has never been stored before.  The
2380 **                     index at pDest->iSDParm+1 hold all prior stores.
2381 */
2382 #define SRT_Union        1  /* Store result as keys in an index */
2383 #define SRT_Except       2  /* Remove result from a UNION index */
2384 #define SRT_Exists       3  /* Store 1 if the result is not empty */
2385 #define SRT_Discard      4  /* Do not save the results anywhere */
2386 #define SRT_Fifo         5  /* Store result as data with an automatic rowid */
2387 #define SRT_DistFifo     6  /* Like SRT_Fifo, but unique results only */
2388 #define SRT_Queue        7  /* Store result in an queue */
2389 #define SRT_DistQueue    8  /* Like SRT_Queue, but unique results only */
2390 
2391 /* The ORDER BY clause is ignored for all of the above */
2392 #define IgnorableOrderby(X) ((X->eDest)<=SRT_DistQueue)
2393 
2394 #define SRT_Output       9  /* Output each row of result */
2395 #define SRT_Mem         10  /* Store result in a memory cell */
2396 #define SRT_Set         11  /* Store results as keys in an index */
2397 #define SRT_EphemTab    12  /* Create transient tab and store like SRT_Table */
2398 #define SRT_Coroutine   13  /* Generate a single row of result */
2399 #define SRT_Table       14  /* Store result as data with an automatic rowid */
2400 
2401 /*
2402 ** An instance of this object describes where to put of the results of
2403 ** a SELECT statement.
2404 */
2405 struct SelectDest {
2406   u8 eDest;            /* How to dispose of the results.  On of SRT_* above. */
2407   char affSdst;        /* Affinity used when eDest==SRT_Set */
2408   int iSDParm;         /* A parameter used by the eDest disposal method */
2409   int iSdst;           /* Base register where results are written */
2410   int nSdst;           /* Number of registers allocated */
2411   ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
2412 };
2413 
2414 /*
2415 ** During code generation of statements that do inserts into AUTOINCREMENT
2416 ** tables, the following information is attached to the Table.u.autoInc.p
2417 ** pointer of each autoincrement table to record some side information that
2418 ** the code generator needs.  We have to keep per-table autoincrement
2419 ** information in case inserts are down within triggers.  Triggers do not
2420 ** normally coordinate their activities, but we do need to coordinate the
2421 ** loading and saving of autoincrement information.
2422 */
2423 struct AutoincInfo {
2424   AutoincInfo *pNext;   /* Next info block in a list of them all */
2425   Table *pTab;          /* Table this info block refers to */
2426   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
2427   int regCtr;           /* Memory register holding the rowid counter */
2428 };
2429 
2430 /*
2431 ** Size of the column cache
2432 */
2433 #ifndef SQLITE_N_COLCACHE
2434 # define SQLITE_N_COLCACHE 10
2435 #endif
2436 
2437 /*
2438 ** At least one instance of the following structure is created for each
2439 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
2440 ** statement. All such objects are stored in the linked list headed at
2441 ** Parse.pTriggerPrg and deleted once statement compilation has been
2442 ** completed.
2443 **
2444 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
2445 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
2446 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
2447 ** The Parse.pTriggerPrg list never contains two entries with the same
2448 ** values for both pTrigger and orconf.
2449 **
2450 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
2451 ** accessed (or set to 0 for triggers fired as a result of INSERT
2452 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
2453 ** a mask of new.* columns used by the program.
2454 */
2455 struct TriggerPrg {
2456   Trigger *pTrigger;      /* Trigger this program was coded from */
2457   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
2458   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
2459   int orconf;             /* Default ON CONFLICT policy */
2460   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
2461 };
2462 
2463 /*
2464 ** The yDbMask datatype for the bitmask of all attached databases.
2465 */
2466 #if SQLITE_MAX_ATTACHED>30
2467   typedef unsigned char yDbMask[(SQLITE_MAX_ATTACHED+9)/8];
2468 # define DbMaskTest(M,I)    (((M)[(I)/8]&(1<<((I)&7)))!=0)
2469 # define DbMaskZero(M)      memset((M),0,sizeof(M))
2470 # define DbMaskSet(M,I)     (M)[(I)/8]|=(1<<((I)&7))
2471 # define DbMaskAllZero(M)   sqlite3DbMaskAllZero(M)
2472 # define DbMaskNonZero(M)   (sqlite3DbMaskAllZero(M)==0)
2473 #else
2474   typedef unsigned int yDbMask;
2475 # define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
2476 # define DbMaskZero(M)      (M)=0
2477 # define DbMaskSet(M,I)     (M)|=(((yDbMask)1)<<(I))
2478 # define DbMaskAllZero(M)   (M)==0
2479 # define DbMaskNonZero(M)   (M)!=0
2480 #endif
2481 
2482 /*
2483 ** An SQL parser context.  A copy of this structure is passed through
2484 ** the parser and down into all the parser action routine in order to
2485 ** carry around information that is global to the entire parse.
2486 **
2487 ** The structure is divided into two parts.  When the parser and code
2488 ** generate call themselves recursively, the first part of the structure
2489 ** is constant but the second part is reset at the beginning and end of
2490 ** each recursion.
2491 **
2492 ** The nTableLock and aTableLock variables are only used if the shared-cache
2493 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
2494 ** used to store the set of table-locks required by the statement being
2495 ** compiled. Function sqlite3TableLock() is used to add entries to the
2496 ** list.
2497 */
2498 struct Parse {
2499   sqlite3 *db;         /* The main database structure */
2500   char *zErrMsg;       /* An error message */
2501   Vdbe *pVdbe;         /* An engine for executing database bytecode */
2502   int rc;              /* Return code from execution */
2503   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
2504   u8 checkSchema;      /* Causes schema cookie check after an error */
2505   u8 nested;           /* Number of nested calls to the parser/code generator */
2506   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
2507   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
2508   u8 mayAbort;         /* True if statement may throw an ABORT exception */
2509   u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
2510   u8 okConstFactor;    /* OK to factor out constants */
2511   int aTempReg[8];     /* Holding area for temporary registers */
2512   int nRangeReg;       /* Size of the temporary register block */
2513   int iRangeReg;       /* First register in temporary register block */
2514   int nErr;            /* Number of errors seen */
2515   int nTab;            /* Number of previously allocated VDBE cursors */
2516   int nMem;            /* Number of memory cells used so far */
2517   int nSet;            /* Number of sets used so far */
2518   int nOnce;           /* Number of OP_Once instructions so far */
2519   int nOpAlloc;        /* Number of slots allocated for Vdbe.aOp[] */
2520   int iFixedOp;        /* Never back out opcodes iFixedOp-1 or earlier */
2521   int ckBase;          /* Base register of data during check constraints */
2522   int iPartIdxTab;     /* Table corresponding to a partial index */
2523   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
2524   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
2525   int nLabel;          /* Number of labels used */
2526   int *aLabel;         /* Space to hold the labels */
2527   struct yColCache {
2528     int iTable;           /* Table cursor number */
2529     i16 iColumn;          /* Table column number */
2530     u8 tempReg;           /* iReg is a temp register that needs to be freed */
2531     int iLevel;           /* Nesting level */
2532     int iReg;             /* Reg with value of this column. 0 means none. */
2533     int lru;              /* Least recently used entry has the smallest value */
2534   } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
2535   ExprList *pConstExpr;/* Constant expressions */
2536   Token constraintName;/* Name of the constraint currently being parsed */
2537   yDbMask writeMask;   /* Start a write transaction on these databases */
2538   yDbMask cookieMask;  /* Bitmask of schema verified databases */
2539   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
2540   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
2541   int regRoot;         /* Register holding root page number for new objects */
2542   int nMaxArg;         /* Max args passed to user function by sub-program */
2543 #ifndef SQLITE_OMIT_SHARED_CACHE
2544   int nTableLock;        /* Number of locks in aTableLock */
2545   TableLock *aTableLock; /* Required table locks for shared-cache mode */
2546 #endif
2547   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
2548 
2549   /* Information used while coding trigger programs. */
2550   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
2551   Table *pTriggerTab;  /* Table triggers are being coded for */
2552   int addrCrTab;       /* Address of OP_CreateTable opcode on CREATE TABLE */
2553   int addrSkipPK;      /* Address of instruction to skip PRIMARY KEY index */
2554   u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
2555   u32 oldmask;         /* Mask of old.* columns referenced */
2556   u32 newmask;         /* Mask of new.* columns referenced */
2557   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
2558   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
2559   u8 disableTriggers;  /* True to disable triggers */
2560 
2561   /************************************************************************
2562   ** Above is constant between recursions.  Below is reset before and after
2563   ** each recursion.  The boundary between these two regions is determined
2564   ** using offsetof(Parse,nVar) so the nVar field must be the first field
2565   ** in the recursive region.
2566   ************************************************************************/
2567 
2568   int nVar;                 /* Number of '?' variables seen in the SQL so far */
2569   int nzVar;                /* Number of available slots in azVar[] */
2570   u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
2571   u8 bFreeWith;             /* True if pWith should be freed with parser */
2572   u8 explain;               /* True if the EXPLAIN flag is found on the query */
2573 #ifndef SQLITE_OMIT_VIRTUALTABLE
2574   u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
2575   int nVtabLock;            /* Number of virtual tables to lock */
2576 #endif
2577   int nAlias;               /* Number of aliased result set columns */
2578   int nHeight;              /* Expression tree height of current sub-select */
2579 #ifndef SQLITE_OMIT_EXPLAIN
2580   int iSelectId;            /* ID of current select for EXPLAIN output */
2581   int iNextSelectId;        /* Next available select ID for EXPLAIN output */
2582 #endif
2583   char **azVar;             /* Pointers to names of parameters */
2584   Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
2585   const char *zTail;        /* All SQL text past the last semicolon parsed */
2586   Table *pNewTable;         /* A table being constructed by CREATE TABLE */
2587   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
2588   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
2589   Token sNameToken;         /* Token with unqualified schema object name */
2590   Token sLastToken;         /* The last token parsed */
2591 #ifndef SQLITE_OMIT_VIRTUALTABLE
2592   Token sArg;               /* Complete text of a module argument */
2593   Table **apVtabLock;       /* Pointer to virtual tables needing locking */
2594 #endif
2595   Table *pZombieTab;        /* List of Table objects to delete after code gen */
2596   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
2597   With *pWith;              /* Current WITH clause, or NULL */
2598 };
2599 
2600 /*
2601 ** Return true if currently inside an sqlite3_declare_vtab() call.
2602 */
2603 #ifdef SQLITE_OMIT_VIRTUALTABLE
2604   #define IN_DECLARE_VTAB 0
2605 #else
2606   #define IN_DECLARE_VTAB (pParse->declareVtab)
2607 #endif
2608 
2609 /*
2610 ** An instance of the following structure can be declared on a stack and used
2611 ** to save the Parse.zAuthContext value so that it can be restored later.
2612 */
2613 struct AuthContext {
2614   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
2615   Parse *pParse;              /* The Parse structure */
2616 };
2617 
2618 /*
2619 ** Bitfield flags for P5 value in various opcodes.
2620 */
2621 #define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
2622 #define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
2623 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
2624 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
2625 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
2626 #define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
2627 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
2628 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
2629 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
2630 #define OPFLAG_P2ISREG       0x02    /* P2 to OP_Open** is a register number */
2631 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
2632 
2633 /*
2634  * Each trigger present in the database schema is stored as an instance of
2635  * struct Trigger.
2636  *
2637  * Pointers to instances of struct Trigger are stored in two ways.
2638  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
2639  *    database). This allows Trigger structures to be retrieved by name.
2640  * 2. All triggers associated with a single table form a linked list, using the
2641  *    pNext member of struct Trigger. A pointer to the first element of the
2642  *    linked list is stored as the "pTrigger" member of the associated
2643  *    struct Table.
2644  *
2645  * The "step_list" member points to the first element of a linked list
2646  * containing the SQL statements specified as the trigger program.
2647  */
2648 struct Trigger {
2649   char *zName;            /* The name of the trigger                        */
2650   char *table;            /* The table or view to which the trigger applies */
2651   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
2652   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
2653   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
2654   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
2655                              the <column-list> is stored here */
2656   Schema *pSchema;        /* Schema containing the trigger */
2657   Schema *pTabSchema;     /* Schema containing the table */
2658   TriggerStep *step_list; /* Link list of trigger program steps             */
2659   Trigger *pNext;         /* Next trigger associated with the table */
2660 };
2661 
2662 /*
2663 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
2664 ** determine which.
2665 **
2666 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
2667 ** In that cases, the constants below can be ORed together.
2668 */
2669 #define TRIGGER_BEFORE  1
2670 #define TRIGGER_AFTER   2
2671 
2672 /*
2673  * An instance of struct TriggerStep is used to store a single SQL statement
2674  * that is a part of a trigger-program.
2675  *
2676  * Instances of struct TriggerStep are stored in a singly linked list (linked
2677  * using the "pNext" member) referenced by the "step_list" member of the
2678  * associated struct Trigger instance. The first element of the linked list is
2679  * the first step of the trigger-program.
2680  *
2681  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
2682  * "SELECT" statement. The meanings of the other members is determined by the
2683  * value of "op" as follows:
2684  *
2685  * (op == TK_INSERT)
2686  * orconf    -> stores the ON CONFLICT algorithm
2687  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
2688  *              this stores a pointer to the SELECT statement. Otherwise NULL.
2689  * target    -> A token holding the quoted name of the table to insert into.
2690  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
2691  *              this stores values to be inserted. Otherwise NULL.
2692  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
2693  *              statement, then this stores the column-names to be
2694  *              inserted into.
2695  *
2696  * (op == TK_DELETE)
2697  * target    -> A token holding the quoted name of the table to delete from.
2698  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
2699  *              Otherwise NULL.
2700  *
2701  * (op == TK_UPDATE)
2702  * target    -> A token holding the quoted name of the table to update rows of.
2703  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
2704  *              Otherwise NULL.
2705  * pExprList -> A list of the columns to update and the expressions to update
2706  *              them to. See sqlite3Update() documentation of "pChanges"
2707  *              argument.
2708  *
2709  */
2710 struct TriggerStep {
2711   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
2712   u8 orconf;           /* OE_Rollback etc. */
2713   Trigger *pTrig;      /* The trigger that this step is a part of */
2714   Select *pSelect;     /* SELECT statment or RHS of INSERT INTO .. SELECT ... */
2715   Token target;        /* Target table for DELETE, UPDATE, INSERT */
2716   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
2717   ExprList *pExprList; /* SET clause for UPDATE. */
2718   IdList *pIdList;     /* Column names for INSERT */
2719   TriggerStep *pNext;  /* Next in the link-list */
2720   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
2721 };
2722 
2723 /*
2724 ** The following structure contains information used by the sqliteFix...
2725 ** routines as they walk the parse tree to make database references
2726 ** explicit.
2727 */
2728 typedef struct DbFixer DbFixer;
2729 struct DbFixer {
2730   Parse *pParse;      /* The parsing context.  Error messages written here */
2731   Schema *pSchema;    /* Fix items to this schema */
2732   int bVarOnly;       /* Check for variable references only */
2733   const char *zDb;    /* Make sure all objects are contained in this database */
2734   const char *zType;  /* Type of the container - used for error messages */
2735   const Token *pName; /* Name of the container - used for error messages */
2736 };
2737 
2738 /*
2739 ** An objected used to accumulate the text of a string where we
2740 ** do not necessarily know how big the string will be in the end.
2741 */
2742 struct StrAccum {
2743   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
2744   char *zBase;         /* A base allocation.  Not from malloc. */
2745   char *zText;         /* The string collected so far */
2746   int  nChar;          /* Length of the string so far */
2747   int  nAlloc;         /* Amount of space allocated in zText */
2748   int  mxAlloc;        /* Maximum allowed string length */
2749   u8   useMalloc;      /* 0: none,  1: sqlite3DbMalloc,  2: sqlite3_malloc */
2750   u8   accError;       /* STRACCUM_NOMEM or STRACCUM_TOOBIG */
2751 };
2752 #define STRACCUM_NOMEM   1
2753 #define STRACCUM_TOOBIG  2
2754 
2755 /*
2756 ** A pointer to this structure is used to communicate information
2757 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
2758 */
2759 typedef struct {
2760   sqlite3 *db;        /* The database being initialized */
2761   char **pzErrMsg;    /* Error message stored here */
2762   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
2763   int rc;             /* Result code stored here */
2764 } InitData;
2765 
2766 /*
2767 ** Structure containing global configuration data for the SQLite library.
2768 **
2769 ** This structure also contains some state information.
2770 */
2771 struct Sqlite3Config {
2772   int bMemstat;                     /* True to enable memory status */
2773   int bCoreMutex;                   /* True to enable core mutexing */
2774   int bFullMutex;                   /* True to enable full mutexing */
2775   int bOpenUri;                     /* True to interpret filenames as URIs */
2776   int bUseCis;                      /* Use covering indices for full-scans */
2777   int mxStrlen;                     /* Maximum string length */
2778   int neverCorrupt;                 /* Database is always well-formed */
2779   int szLookaside;                  /* Default lookaside buffer size */
2780   int nLookaside;                   /* Default lookaside buffer count */
2781   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
2782   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
2783   sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
2784   void *pHeap;                      /* Heap storage space */
2785   int nHeap;                        /* Size of pHeap[] */
2786   int mnReq, mxReq;                 /* Min and max heap requests sizes */
2787   sqlite3_int64 szMmap;             /* mmap() space per open file */
2788   sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
2789   void *pScratch;                   /* Scratch memory */
2790   int szScratch;                    /* Size of each scratch buffer */
2791   int nScratch;                     /* Number of scratch buffers */
2792   void *pPage;                      /* Page cache memory */
2793   int szPage;                       /* Size of each page in pPage[] */
2794   int nPage;                        /* Number of pages in pPage[] */
2795   int mxParserStack;                /* maximum depth of the parser stack */
2796   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
2797   /* The above might be initialized to non-zero.  The following need to always
2798   ** initially be zero, however. */
2799   int isInit;                       /* True after initialization has finished */
2800   int inProgress;                   /* True while initialization in progress */
2801   int isMutexInit;                  /* True after mutexes are initialized */
2802   int isMallocInit;                 /* True after malloc is initialized */
2803   int isPCacheInit;                 /* True after malloc is initialized */
2804   int nRefInitMutex;                /* Number of users of pInitMutex */
2805   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
2806   void (*xLog)(void*,int,const char*); /* Function for logging */
2807   void *pLogArg;                       /* First argument to xLog() */
2808 #ifdef SQLITE_ENABLE_SQLLOG
2809   void(*xSqllog)(void*,sqlite3*,const char*, int);
2810   void *pSqllogArg;
2811 #endif
2812 #ifdef SQLITE_VDBE_COVERAGE
2813   /* The following callback (if not NULL) is invoked on every VDBE branch
2814   ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
2815   */
2816   void (*xVdbeBranch)(void*,int iSrcLine,u8 eThis,u8 eMx);  /* Callback */
2817   void *pVdbeBranchArg;                                     /* 1st argument */
2818 #endif
2819 #ifndef SQLITE_OMIT_BUILTIN_TEST
2820   int (*xTestCallback)(int);        /* Invoked by sqlite3FaultSim() */
2821 #endif
2822   int bLocaltimeFault;              /* True to fail localtime() calls */
2823 };
2824 
2825 /*
2826 ** This macro is used inside of assert() statements to indicate that
2827 ** the assert is only valid on a well-formed database.  Instead of:
2828 **
2829 **     assert( X );
2830 **
2831 ** One writes:
2832 **
2833 **     assert( X || CORRUPT_DB );
2834 **
2835 ** CORRUPT_DB is true during normal operation.  CORRUPT_DB does not indicate
2836 ** that the database is definitely corrupt, only that it might be corrupt.
2837 ** For most test cases, CORRUPT_DB is set to false using a special
2838 ** sqlite3_test_control().  This enables assert() statements to prove
2839 ** things that are always true for well-formed databases.
2840 */
2841 #define CORRUPT_DB  (sqlite3Config.neverCorrupt==0)
2842 
2843 /*
2844 ** Context pointer passed down through the tree-walk.
2845 */
2846 struct Walker {
2847   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
2848   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
2849   void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
2850   Parse *pParse;                            /* Parser context.  */
2851   int walkerDepth;                          /* Number of subqueries */
2852   union {                                   /* Extra data for callback */
2853     NameContext *pNC;                          /* Naming context */
2854     int i;                                     /* Integer value */
2855     SrcList *pSrcList;                         /* FROM clause */
2856     struct SrcCount *pSrcCount;                /* Counting column references */
2857   } u;
2858 };
2859 
2860 /* Forward declarations */
2861 int sqlite3WalkExpr(Walker*, Expr*);
2862 int sqlite3WalkExprList(Walker*, ExprList*);
2863 int sqlite3WalkSelect(Walker*, Select*);
2864 int sqlite3WalkSelectExpr(Walker*, Select*);
2865 int sqlite3WalkSelectFrom(Walker*, Select*);
2866 
2867 /*
2868 ** Return code from the parse-tree walking primitives and their
2869 ** callbacks.
2870 */
2871 #define WRC_Continue    0   /* Continue down into children */
2872 #define WRC_Prune       1   /* Omit children but continue walking siblings */
2873 #define WRC_Abort       2   /* Abandon the tree walk */
2874 
2875 /*
2876 ** An instance of this structure represents a set of one or more CTEs
2877 ** (common table expressions) created by a single WITH clause.
2878 */
2879 struct With {
2880   int nCte;                       /* Number of CTEs in the WITH clause */
2881   With *pOuter;                   /* Containing WITH clause, or NULL */
2882   struct Cte {                    /* For each CTE in the WITH clause.... */
2883     char *zName;                    /* Name of this CTE */
2884     ExprList *pCols;                /* List of explicit column names, or NULL */
2885     Select *pSelect;                /* The definition of this CTE */
2886     const char *zErr;               /* Error message for circular references */
2887   } a[1];
2888 };
2889 
2890 /*
2891 ** Assuming zIn points to the first byte of a UTF-8 character,
2892 ** advance zIn to point to the first byte of the next UTF-8 character.
2893 */
2894 #define SQLITE_SKIP_UTF8(zIn) {                        \
2895   if( (*(zIn++))>=0xc0 ){                              \
2896     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
2897   }                                                    \
2898 }
2899 
2900 /*
2901 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
2902 ** the same name but without the _BKPT suffix.  These macros invoke
2903 ** routines that report the line-number on which the error originated
2904 ** using sqlite3_log().  The routines also provide a convenient place
2905 ** to set a debugger breakpoint.
2906 */
2907 int sqlite3CorruptError(int);
2908 int sqlite3MisuseError(int);
2909 int sqlite3CantopenError(int);
2910 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
2911 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
2912 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
2913 
2914 
2915 /*
2916 ** FTS4 is really an extension for FTS3.  It is enabled using the
2917 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also call
2918 ** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
2919 */
2920 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
2921 # define SQLITE_ENABLE_FTS3
2922 #endif
2923 
2924 /*
2925 ** The ctype.h header is needed for non-ASCII systems.  It is also
2926 ** needed by FTS3 when FTS3 is included in the amalgamation.
2927 */
2928 #if !defined(SQLITE_ASCII) || \
2929     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
2930 # include <ctype.h>
2931 #endif
2932 
2933 /*
2934 ** The following macros mimic the standard library functions toupper(),
2935 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
2936 ** sqlite versions only work for ASCII characters, regardless of locale.
2937 */
2938 #ifdef SQLITE_ASCII
2939 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
2940 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
2941 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
2942 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
2943 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
2944 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
2945 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
2946 #else
2947 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
2948 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
2949 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
2950 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
2951 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
2952 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
2953 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
2954 #endif
2955 
2956 /*
2957 ** Internal function prototypes
2958 */
2959 #define sqlite3StrICmp sqlite3_stricmp
2960 int sqlite3Strlen30(const char*);
2961 #define sqlite3StrNICmp sqlite3_strnicmp
2962 
2963 int sqlite3MallocInit(void);
2964 void sqlite3MallocEnd(void);
2965 void *sqlite3Malloc(int);
2966 void *sqlite3MallocZero(int);
2967 void *sqlite3DbMallocZero(sqlite3*, int);
2968 void *sqlite3DbMallocRaw(sqlite3*, int);
2969 char *sqlite3DbStrDup(sqlite3*,const char*);
2970 char *sqlite3DbStrNDup(sqlite3*,const char*, int);
2971 void *sqlite3Realloc(void*, int);
2972 void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
2973 void *sqlite3DbRealloc(sqlite3 *, void *, int);
2974 void sqlite3DbFree(sqlite3*, void*);
2975 int sqlite3MallocSize(void*);
2976 int sqlite3DbMallocSize(sqlite3*, void*);
2977 void *sqlite3ScratchMalloc(int);
2978 void sqlite3ScratchFree(void*);
2979 void *sqlite3PageMalloc(int);
2980 void sqlite3PageFree(void*);
2981 void sqlite3MemSetDefault(void);
2982 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
2983 int sqlite3HeapNearlyFull(void);
2984 
2985 /*
2986 ** On systems with ample stack space and that support alloca(), make
2987 ** use of alloca() to obtain space for large automatic objects.  By default,
2988 ** obtain space from malloc().
2989 **
2990 ** The alloca() routine never returns NULL.  This will cause code paths
2991 ** that deal with sqlite3StackAlloc() failures to be unreachable.
2992 */
2993 #ifdef SQLITE_USE_ALLOCA
2994 # define sqlite3StackAllocRaw(D,N)   alloca(N)
2995 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
2996 # define sqlite3StackFree(D,P)
2997 #else
2998 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
2999 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
3000 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
3001 #endif
3002 
3003 #ifdef SQLITE_ENABLE_MEMSYS3
3004 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
3005 #endif
3006 #ifdef SQLITE_ENABLE_MEMSYS5
3007 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
3008 #endif
3009 
3010 
3011 #ifndef SQLITE_MUTEX_OMIT
3012   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
3013   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
3014   sqlite3_mutex *sqlite3MutexAlloc(int);
3015   int sqlite3MutexInit(void);
3016   int sqlite3MutexEnd(void);
3017 #endif
3018 
3019 int sqlite3StatusValue(int);
3020 void sqlite3StatusAdd(int, int);
3021 void sqlite3StatusSet(int, int);
3022 
3023 #ifndef SQLITE_OMIT_FLOATING_POINT
3024   int sqlite3IsNaN(double);
3025 #else
3026 # define sqlite3IsNaN(X)  0
3027 #endif
3028 
3029 /*
3030 ** An instance of the following structure holds information about SQL
3031 ** functions arguments that are the parameters to the printf() function.
3032 */
3033 struct PrintfArguments {
3034   int nArg;                /* Total number of arguments */
3035   int nUsed;               /* Number of arguments used so far */
3036   sqlite3_value **apArg;   /* The argument values */
3037 };
3038 
3039 #define SQLITE_PRINTF_INTERNAL 0x01
3040 #define SQLITE_PRINTF_SQLFUNC  0x02
3041 void sqlite3VXPrintf(StrAccum*, u32, const char*, va_list);
3042 void sqlite3XPrintf(StrAccum*, u32, const char*, ...);
3043 char *sqlite3MPrintf(sqlite3*,const char*, ...);
3044 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
3045 char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
3046 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
3047   void sqlite3DebugPrintf(const char*, ...);
3048 #endif
3049 #if defined(SQLITE_TEST)
3050   void *sqlite3TestTextToPtr(const char*);
3051 #endif
3052 
3053 /* Output formatting for SQLITE_TESTCTRL_EXPLAIN */
3054 #if defined(SQLITE_ENABLE_TREE_EXPLAIN)
3055   void sqlite3ExplainBegin(Vdbe*);
3056   void sqlite3ExplainPrintf(Vdbe*, const char*, ...);
3057   void sqlite3ExplainNL(Vdbe*);
3058   void sqlite3ExplainPush(Vdbe*);
3059   void sqlite3ExplainPop(Vdbe*);
3060   void sqlite3ExplainFinish(Vdbe*);
3061   void sqlite3ExplainSelect(Vdbe*, Select*);
3062   void sqlite3ExplainExpr(Vdbe*, Expr*);
3063   void sqlite3ExplainExprList(Vdbe*, ExprList*);
3064   const char *sqlite3VdbeExplanation(Vdbe*);
3065 #else
3066 # define sqlite3ExplainBegin(X)
3067 # define sqlite3ExplainSelect(A,B)
3068 # define sqlite3ExplainExpr(A,B)
3069 # define sqlite3ExplainExprList(A,B)
3070 # define sqlite3ExplainFinish(X)
3071 # define sqlite3VdbeExplanation(X) 0
3072 #endif
3073 
3074 
3075 void sqlite3SetString(char **, sqlite3*, const char*, ...);
3076 void sqlite3ErrorMsg(Parse*, const char*, ...);
3077 int sqlite3Dequote(char*);
3078 int sqlite3KeywordCode(const unsigned char*, int);
3079 int sqlite3RunParser(Parse*, const char*, char **);
3080 void sqlite3FinishCoding(Parse*);
3081 int sqlite3GetTempReg(Parse*);
3082 void sqlite3ReleaseTempReg(Parse*,int);
3083 int sqlite3GetTempRange(Parse*,int);
3084 void sqlite3ReleaseTempRange(Parse*,int,int);
3085 void sqlite3ClearTempRegCache(Parse*);
3086 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
3087 Expr *sqlite3Expr(sqlite3*,int,const char*);
3088 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
3089 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
3090 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
3091 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
3092 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
3093 void sqlite3ExprDelete(sqlite3*, Expr*);
3094 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
3095 void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
3096 void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
3097 void sqlite3ExprListDelete(sqlite3*, ExprList*);
3098 int sqlite3Init(sqlite3*, char**);
3099 int sqlite3InitCallback(void*, int, char**, char**);
3100 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
3101 void sqlite3ResetAllSchemasOfConnection(sqlite3*);
3102 void sqlite3ResetOneSchema(sqlite3*,int);
3103 void sqlite3CollapseDatabaseArray(sqlite3*);
3104 void sqlite3BeginParse(Parse*,int);
3105 void sqlite3CommitInternalChanges(sqlite3*);
3106 Table *sqlite3ResultSetOfSelect(Parse*,Select*);
3107 void sqlite3OpenMasterTable(Parse *, int);
3108 Index *sqlite3PrimaryKeyIndex(Table*);
3109 i16 sqlite3ColumnOfIndex(Index*, i16);
3110 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
3111 void sqlite3AddColumn(Parse*,Token*);
3112 void sqlite3AddNotNull(Parse*, int);
3113 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
3114 void sqlite3AddCheckConstraint(Parse*, Expr*);
3115 void sqlite3AddColumnType(Parse*,Token*);
3116 void sqlite3AddDefaultValue(Parse*,ExprSpan*);
3117 void sqlite3AddCollateType(Parse*, Token*);
3118 void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
3119 int sqlite3ParseUri(const char*,const char*,unsigned int*,
3120                     sqlite3_vfs**,char**,char **);
3121 Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
3122 int sqlite3CodeOnce(Parse *);
3123 
3124 #ifdef SQLITE_OMIT_BUILTIN_TEST
3125 # define sqlite3FaultSim(X) SQLITE_OK
3126 #else
3127   int sqlite3FaultSim(int);
3128 #endif
3129 
3130 Bitvec *sqlite3BitvecCreate(u32);
3131 int sqlite3BitvecTest(Bitvec*, u32);
3132 int sqlite3BitvecSet(Bitvec*, u32);
3133 void sqlite3BitvecClear(Bitvec*, u32, void*);
3134 void sqlite3BitvecDestroy(Bitvec*);
3135 u32 sqlite3BitvecSize(Bitvec*);
3136 int sqlite3BitvecBuiltinTest(int,int*);
3137 
3138 RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
3139 void sqlite3RowSetClear(RowSet*);
3140 void sqlite3RowSetInsert(RowSet*, i64);
3141 int sqlite3RowSetTest(RowSet*, int iBatch, i64);
3142 int sqlite3RowSetNext(RowSet*, i64*);
3143 
3144 void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
3145 
3146 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
3147   int sqlite3ViewGetColumnNames(Parse*,Table*);
3148 #else
3149 # define sqlite3ViewGetColumnNames(A,B) 0
3150 #endif
3151 
3152 #if SQLITE_MAX_ATTACHED>30
3153   int sqlite3DbMaskAllZero(yDbMask);
3154 #endif
3155 void sqlite3DropTable(Parse*, SrcList*, int, int);
3156 void sqlite3CodeDropTable(Parse*, Table*, int, int);
3157 void sqlite3DeleteTable(sqlite3*, Table*);
3158 #ifndef SQLITE_OMIT_AUTOINCREMENT
3159   void sqlite3AutoincrementBegin(Parse *pParse);
3160   void sqlite3AutoincrementEnd(Parse *pParse);
3161 #else
3162 # define sqlite3AutoincrementBegin(X)
3163 # define sqlite3AutoincrementEnd(X)
3164 #endif
3165 void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int);
3166 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
3167 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
3168 int sqlite3IdListIndex(IdList*,const char*);
3169 SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
3170 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
3171 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
3172                                       Token*, Select*, Expr*, IdList*);
3173 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
3174 int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
3175 void sqlite3SrcListShiftJoinType(SrcList*);
3176 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
3177 void sqlite3IdListDelete(sqlite3*, IdList*);
3178 void sqlite3SrcListDelete(sqlite3*, SrcList*);
3179 Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
3180 Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
3181                           Expr*, int, int);
3182 void sqlite3DropIndex(Parse*, SrcList*, int);
3183 int sqlite3Select(Parse*, Select*, SelectDest*);
3184 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
3185                          Expr*,ExprList*,u16,Expr*,Expr*);
3186 void sqlite3SelectDelete(sqlite3*, Select*);
3187 Table *sqlite3SrcListLookup(Parse*, SrcList*);
3188 int sqlite3IsReadOnly(Parse*, Table*, int);
3189 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
3190 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
3191 Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,Expr*,char*);
3192 #endif
3193 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
3194 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
3195 WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
3196 void sqlite3WhereEnd(WhereInfo*);
3197 u64 sqlite3WhereOutputRowCount(WhereInfo*);
3198 int sqlite3WhereIsDistinct(WhereInfo*);
3199 int sqlite3WhereIsOrdered(WhereInfo*);
3200 int sqlite3WhereIsSorted(WhereInfo*);
3201 int sqlite3WhereContinueLabel(WhereInfo*);
3202 int sqlite3WhereBreakLabel(WhereInfo*);
3203 int sqlite3WhereOkOnePass(WhereInfo*, int*);
3204 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
3205 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
3206 void sqlite3ExprCodeMove(Parse*, int, int, int);
3207 void sqlite3ExprCacheStore(Parse*, int, int, int);
3208 void sqlite3ExprCachePush(Parse*);
3209 void sqlite3ExprCachePop(Parse*);
3210 void sqlite3ExprCacheRemove(Parse*, int, int);
3211 void sqlite3ExprCacheClear(Parse*);
3212 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
3213 void sqlite3ExprCode(Parse*, Expr*, int);
3214 void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
3215 void sqlite3ExprCodeAtInit(Parse*, Expr*, int, u8);
3216 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
3217 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
3218 void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
3219 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, u8);
3220 #define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
3221 #define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
3222 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
3223 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
3224 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
3225 Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
3226 Table *sqlite3LocateTableItem(Parse*,int isView,struct SrcList_item *);
3227 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
3228 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
3229 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
3230 void sqlite3Vacuum(Parse*);
3231 int sqlite3RunVacuum(char**, sqlite3*);
3232 char *sqlite3NameFromToken(sqlite3*, Token*);
3233 int sqlite3ExprCompare(Expr*, Expr*, int);
3234 int sqlite3ExprListCompare(ExprList*, ExprList*, int);
3235 int sqlite3ExprImpliesExpr(Expr*, Expr*, int);
3236 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
3237 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
3238 int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
3239 Vdbe *sqlite3GetVdbe(Parse*);
3240 void sqlite3PrngSaveState(void);
3241 void sqlite3PrngRestoreState(void);
3242 void sqlite3RollbackAll(sqlite3*,int);
3243 void sqlite3CodeVerifySchema(Parse*, int);
3244 void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
3245 void sqlite3BeginTransaction(Parse*, int);
3246 void sqlite3CommitTransaction(Parse*);
3247 void sqlite3RollbackTransaction(Parse*);
3248 void sqlite3Savepoint(Parse*, int, Token*);
3249 void sqlite3CloseSavepoints(sqlite3 *);
3250 void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
3251 int sqlite3ExprIsConstant(Expr*);
3252 int sqlite3ExprIsConstantNotJoin(Expr*);
3253 int sqlite3ExprIsConstantOrFunction(Expr*);
3254 int sqlite3ExprIsInteger(Expr*, int*);
3255 int sqlite3ExprCanBeNull(const Expr*);
3256 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
3257 int sqlite3IsRowid(const char*);
3258 void sqlite3GenerateRowDelete(Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8);
3259 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*);
3260 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
3261 void sqlite3ResolvePartIdxLabel(Parse*,int);
3262 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
3263                                      u8,u8,int,int*);
3264 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
3265 int sqlite3OpenTableAndIndices(Parse*, Table*, int, int, u8*, int*, int*);
3266 void sqlite3BeginWriteOperation(Parse*, int, int);
3267 void sqlite3MultiWrite(Parse*);
3268 void sqlite3MayAbort(Parse*);
3269 void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
3270 void sqlite3UniqueConstraint(Parse*, int, Index*);
3271 void sqlite3RowidConstraint(Parse*, int, Table*);
3272 Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
3273 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
3274 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
3275 IdList *sqlite3IdListDup(sqlite3*,IdList*);
3276 Select *sqlite3SelectDup(sqlite3*,Select*,int);
3277 void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
3278 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
3279 void sqlite3RegisterBuiltinFunctions(sqlite3*);
3280 void sqlite3RegisterDateTimeFunctions(void);
3281 void sqlite3RegisterGlobalFunctions(void);
3282 int sqlite3SafetyCheckOk(sqlite3*);
3283 int sqlite3SafetyCheckSickOrOk(sqlite3*);
3284 void sqlite3ChangeCookie(Parse*, int);
3285 
3286 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
3287 void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
3288 #endif
3289 
3290 #ifndef SQLITE_OMIT_TRIGGER
3291   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
3292                            Expr*,int, int);
3293   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
3294   void sqlite3DropTrigger(Parse*, SrcList*, int);
3295   void sqlite3DropTriggerPtr(Parse*, Trigger*);
3296   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
3297   Trigger *sqlite3TriggerList(Parse *, Table *);
3298   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
3299                             int, int, int);
3300   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
3301   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
3302   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
3303   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
3304   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
3305                                         Select*,u8);
3306   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
3307   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
3308   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
3309   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
3310   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
3311 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
3312 #else
3313 # define sqlite3TriggersExist(B,C,D,E,F) 0
3314 # define sqlite3DeleteTrigger(A,B)
3315 # define sqlite3DropTriggerPtr(A,B)
3316 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
3317 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
3318 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
3319 # define sqlite3TriggerList(X, Y) 0
3320 # define sqlite3ParseToplevel(p) p
3321 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
3322 #endif
3323 
3324 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
3325 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
3326 void sqlite3DeferForeignKey(Parse*, int);
3327 #ifndef SQLITE_OMIT_AUTHORIZATION
3328   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
3329   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
3330   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
3331   void sqlite3AuthContextPop(AuthContext*);
3332   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
3333 #else
3334 # define sqlite3AuthRead(a,b,c,d)
3335 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
3336 # define sqlite3AuthContextPush(a,b,c)
3337 # define sqlite3AuthContextPop(a)  ((void)(a))
3338 #endif
3339 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
3340 void sqlite3Detach(Parse*, Expr*);
3341 void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
3342 int sqlite3FixSrcList(DbFixer*, SrcList*);
3343 int sqlite3FixSelect(DbFixer*, Select*);
3344 int sqlite3FixExpr(DbFixer*, Expr*);
3345 int sqlite3FixExprList(DbFixer*, ExprList*);
3346 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
3347 int sqlite3AtoF(const char *z, double*, int, u8);
3348 int sqlite3GetInt32(const char *, int*);
3349 int sqlite3Atoi(const char*);
3350 int sqlite3Utf16ByteLen(const void *pData, int nChar);
3351 int sqlite3Utf8CharLen(const char *pData, int nByte);
3352 u32 sqlite3Utf8Read(const u8**);
3353 LogEst sqlite3LogEst(u64);
3354 LogEst sqlite3LogEstAdd(LogEst,LogEst);
3355 #ifndef SQLITE_OMIT_VIRTUALTABLE
3356 LogEst sqlite3LogEstFromDouble(double);
3357 #endif
3358 u64 sqlite3LogEstToInt(LogEst);
3359 
3360 /*
3361 ** Routines to read and write variable-length integers.  These used to
3362 ** be defined locally, but now we use the varint routines in the util.c
3363 ** file.
3364 */
3365 int sqlite3PutVarint(unsigned char*, u64);
3366 u8 sqlite3GetVarint(const unsigned char *, u64 *);
3367 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
3368 int sqlite3VarintLen(u64 v);
3369 
3370 /*
3371 ** The common case is for a varint to be a single byte.  They following
3372 ** macros handle the common case without a procedure call, but then call
3373 ** the procedure for larger varints.
3374 */
3375 #define getVarint32(A,B)  \
3376   (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
3377 #define putVarint32(A,B)  \
3378   (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
3379   sqlite3PutVarint((A),(B)))
3380 #define getVarint    sqlite3GetVarint
3381 #define putVarint    sqlite3PutVarint
3382 
3383 
3384 const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
3385 void sqlite3TableAffinity(Vdbe*, Table*, int);
3386 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
3387 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
3388 char sqlite3ExprAffinity(Expr *pExpr);
3389 int sqlite3Atoi64(const char*, i64*, int, u8);
3390 int sqlite3DecOrHexToI64(const char*, i64*);
3391 void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
3392 void sqlite3Error(sqlite3*,int);
3393 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
3394 u8 sqlite3HexToInt(int h);
3395 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
3396 
3397 #if defined(SQLITE_TEST)
3398 const char *sqlite3ErrName(int);
3399 #endif
3400 
3401 const char *sqlite3ErrStr(int);
3402 int sqlite3ReadSchema(Parse *pParse);
3403 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
3404 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
3405 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
3406 Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*);
3407 Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
3408 Expr *sqlite3ExprSkipCollate(Expr*);
3409 int sqlite3CheckCollSeq(Parse *, CollSeq *);
3410 int sqlite3CheckObjectName(Parse *, const char *);
3411 void sqlite3VdbeSetChanges(sqlite3 *, int);
3412 int sqlite3AddInt64(i64*,i64);
3413 int sqlite3SubInt64(i64*,i64);
3414 int sqlite3MulInt64(i64*,i64);
3415 int sqlite3AbsInt32(int);
3416 #ifdef SQLITE_ENABLE_8_3_NAMES
3417 void sqlite3FileSuffix3(const char*, char*);
3418 #else
3419 # define sqlite3FileSuffix3(X,Y)
3420 #endif
3421 u8 sqlite3GetBoolean(const char *z,u8);
3422 
3423 const void *sqlite3ValueText(sqlite3_value*, u8);
3424 int sqlite3ValueBytes(sqlite3_value*, u8);
3425 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
3426                         void(*)(void*));
3427 void sqlite3ValueSetNull(sqlite3_value*);
3428 void sqlite3ValueFree(sqlite3_value*);
3429 sqlite3_value *sqlite3ValueNew(sqlite3 *);
3430 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
3431 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
3432 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
3433 #ifndef SQLITE_AMALGAMATION
3434 extern const unsigned char sqlite3OpcodeProperty[];
3435 extern const unsigned char sqlite3UpperToLower[];
3436 extern const unsigned char sqlite3CtypeMap[];
3437 extern const Token sqlite3IntTokens[];
3438 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
3439 extern SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
3440 #ifndef SQLITE_OMIT_WSD
3441 extern int sqlite3PendingByte;
3442 #endif
3443 #endif
3444 void sqlite3RootPageMoved(sqlite3*, int, int, int);
3445 void sqlite3Reindex(Parse*, Token*, Token*);
3446 void sqlite3AlterFunctions(void);
3447 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
3448 int sqlite3GetToken(const unsigned char *, int *);
3449 void sqlite3NestedParse(Parse*, const char*, ...);
3450 void sqlite3ExpirePreparedStatements(sqlite3*);
3451 int sqlite3CodeSubselect(Parse *, Expr *, int, int);
3452 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
3453 int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
3454 int sqlite3ResolveExprNames(NameContext*, Expr*);
3455 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
3456 void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
3457 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
3458 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
3459 void sqlite3AlterFinishAddColumn(Parse *, Token *);
3460 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
3461 CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
3462 char sqlite3AffinityType(const char*, u8*);
3463 void sqlite3Analyze(Parse*, Token*, Token*);
3464 int sqlite3InvokeBusyHandler(BusyHandler*);
3465 int sqlite3FindDb(sqlite3*, Token*);
3466 int sqlite3FindDbName(sqlite3 *, const char *);
3467 int sqlite3AnalysisLoad(sqlite3*,int iDB);
3468 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
3469 void sqlite3DefaultRowEst(Index*);
3470 void sqlite3RegisterLikeFunctions(sqlite3*, int);
3471 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
3472 void sqlite3MinimumFileFormat(Parse*, int, int);
3473 void sqlite3SchemaClear(void *);
3474 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
3475 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
3476 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
3477 void sqlite3KeyInfoUnref(KeyInfo*);
3478 KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
3479 KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
3480 #ifdef SQLITE_DEBUG
3481 int sqlite3KeyInfoIsWriteable(KeyInfo*);
3482 #endif
3483 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
3484   void (*)(sqlite3_context*,int,sqlite3_value **),
3485   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
3486   FuncDestructor *pDestructor
3487 );
3488 int sqlite3ApiExit(sqlite3 *db, int);
3489 int sqlite3OpenTempDatabase(Parse *);
3490 
3491 void sqlite3StrAccumInit(StrAccum*, char*, int, int);
3492 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
3493 void sqlite3StrAccumAppendAll(StrAccum*,const char*);
3494 void sqlite3AppendSpace(StrAccum*,int);
3495 char *sqlite3StrAccumFinish(StrAccum*);
3496 void sqlite3StrAccumReset(StrAccum*);
3497 void sqlite3SelectDestInit(SelectDest*,int,int);
3498 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
3499 
3500 void sqlite3BackupRestart(sqlite3_backup *);
3501 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
3502 
3503 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4
3504 void sqlite3AnalyzeFunctions(void);
3505 int sqlite3Stat4ProbeSetValue(Parse*,Index*,UnpackedRecord**,Expr*,u8,int,int*);
3506 int sqlite3Stat4ValueFromExpr(Parse*, Expr*, u8, sqlite3_value**);
3507 void sqlite3Stat4ProbeFree(UnpackedRecord*);
3508 int sqlite3Stat4Column(sqlite3*, const void*, int, int, sqlite3_value**);
3509 #endif
3510 
3511 /*
3512 ** The interface to the LEMON-generated parser
3513 */
3514 void *sqlite3ParserAlloc(void*(*)(size_t));
3515 void sqlite3ParserFree(void*, void(*)(void*));
3516 void sqlite3Parser(void*, int, Token, Parse*);
3517 #ifdef YYTRACKMAXSTACKDEPTH
3518   int sqlite3ParserStackPeak(void*);
3519 #endif
3520 
3521 void sqlite3AutoLoadExtensions(sqlite3*);
3522 #ifndef SQLITE_OMIT_LOAD_EXTENSION
3523   void sqlite3CloseExtensions(sqlite3*);
3524 #else
3525 # define sqlite3CloseExtensions(X)
3526 #endif
3527 
3528 #ifndef SQLITE_OMIT_SHARED_CACHE
3529   void sqlite3TableLock(Parse *, int, int, u8, const char *);
3530 #else
3531   #define sqlite3TableLock(v,w,x,y,z)
3532 #endif
3533 
3534 #ifdef SQLITE_TEST
3535   int sqlite3Utf8To8(unsigned char*);
3536 #endif
3537 
3538 #ifdef SQLITE_OMIT_VIRTUALTABLE
3539 #  define sqlite3VtabClear(Y)
3540 #  define sqlite3VtabSync(X,Y) SQLITE_OK
3541 #  define sqlite3VtabRollback(X)
3542 #  define sqlite3VtabCommit(X)
3543 #  define sqlite3VtabInSync(db) 0
3544 #  define sqlite3VtabLock(X)
3545 #  define sqlite3VtabUnlock(X)
3546 #  define sqlite3VtabUnlockList(X)
3547 #  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
3548 #  define sqlite3GetVTable(X,Y)  ((VTable*)0)
3549 #else
3550    void sqlite3VtabClear(sqlite3 *db, Table*);
3551    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
3552    int sqlite3VtabSync(sqlite3 *db, Vdbe*);
3553    int sqlite3VtabRollback(sqlite3 *db);
3554    int sqlite3VtabCommit(sqlite3 *db);
3555    void sqlite3VtabLock(VTable *);
3556    void sqlite3VtabUnlock(VTable *);
3557    void sqlite3VtabUnlockList(sqlite3*);
3558    int sqlite3VtabSavepoint(sqlite3 *, int, int);
3559    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
3560    VTable *sqlite3GetVTable(sqlite3*, Table*);
3561 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
3562 #endif
3563 void sqlite3VtabMakeWritable(Parse*,Table*);
3564 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
3565 void sqlite3VtabFinishParse(Parse*, Token*);
3566 void sqlite3VtabArgInit(Parse*);
3567 void sqlite3VtabArgExtend(Parse*, Token*);
3568 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
3569 int sqlite3VtabCallConnect(Parse*, Table*);
3570 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
3571 int sqlite3VtabBegin(sqlite3 *, VTable *);
3572 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
3573 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
3574 sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
3575 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
3576 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
3577 void sqlite3ParserReset(Parse*);
3578 int sqlite3Reprepare(Vdbe*);
3579 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
3580 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
3581 int sqlite3TempInMemory(const sqlite3*);
3582 const char *sqlite3JournalModename(int);
3583 #ifndef SQLITE_OMIT_WAL
3584   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
3585   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
3586 #endif
3587 #ifndef SQLITE_OMIT_CTE
3588   With *sqlite3WithAdd(Parse*,With*,Token*,ExprList*,Select*);
3589   void sqlite3WithDelete(sqlite3*,With*);
3590   void sqlite3WithPush(Parse*, With*, u8);
3591 #else
3592 #define sqlite3WithPush(x,y,z)
3593 #define sqlite3WithDelete(x,y)
3594 #endif
3595 
3596 /* Declarations for functions in fkey.c. All of these are replaced by
3597 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
3598 ** key functionality is available. If OMIT_TRIGGER is defined but
3599 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
3600 ** this case foreign keys are parsed, but no other functionality is
3601 ** provided (enforcement of FK constraints requires the triggers sub-system).
3602 */
3603 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
3604   void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
3605   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
3606   void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
3607   int sqlite3FkRequired(Parse*, Table*, int*, int);
3608   u32 sqlite3FkOldmask(Parse*, Table*);
3609   FKey *sqlite3FkReferences(Table *);
3610 #else
3611   #define sqlite3FkActions(a,b,c,d,e,f)
3612   #define sqlite3FkCheck(a,b,c,d,e,f)
3613   #define sqlite3FkDropTable(a,b,c)
3614   #define sqlite3FkOldmask(a,b)         0
3615   #define sqlite3FkRequired(a,b,c,d)    0
3616 #endif
3617 #ifndef SQLITE_OMIT_FOREIGN_KEY
3618   void sqlite3FkDelete(sqlite3 *, Table*);
3619   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
3620 #else
3621   #define sqlite3FkDelete(a,b)
3622   #define sqlite3FkLocateIndex(a,b,c,d,e)
3623 #endif
3624 
3625 
3626 /*
3627 ** Available fault injectors.  Should be numbered beginning with 0.
3628 */
3629 #define SQLITE_FAULTINJECTOR_MALLOC     0
3630 #define SQLITE_FAULTINJECTOR_COUNT      1
3631 
3632 /*
3633 ** The interface to the code in fault.c used for identifying "benign"
3634 ** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
3635 ** is not defined.
3636 */
3637 #ifndef SQLITE_OMIT_BUILTIN_TEST
3638   void sqlite3BeginBenignMalloc(void);
3639   void sqlite3EndBenignMalloc(void);
3640 #else
3641   #define sqlite3BeginBenignMalloc()
3642   #define sqlite3EndBenignMalloc()
3643 #endif
3644 
3645 /*
3646 ** Allowed return values from sqlite3FindInIndex()
3647 */
3648 #define IN_INDEX_ROWID        1   /* Search the rowid of the table */
3649 #define IN_INDEX_EPH          2   /* Search an ephemeral b-tree */
3650 #define IN_INDEX_INDEX_ASC    3   /* Existing index ASCENDING */
3651 #define IN_INDEX_INDEX_DESC   4   /* Existing index DESCENDING */
3652 #define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
3653 /*
3654 ** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
3655 */
3656 #define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
3657 #define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
3658 #define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
3659 int sqlite3FindInIndex(Parse *, Expr *, u32, int*);
3660 
3661 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
3662   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
3663   int sqlite3JournalSize(sqlite3_vfs *);
3664   int sqlite3JournalCreate(sqlite3_file *);
3665   int sqlite3JournalExists(sqlite3_file *p);
3666 #else
3667   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
3668   #define sqlite3JournalExists(p) 1
3669 #endif
3670 
3671 void sqlite3MemJournalOpen(sqlite3_file *);
3672 int sqlite3MemJournalSize(void);
3673 int sqlite3IsMemJournal(sqlite3_file *);
3674 
3675 #if SQLITE_MAX_EXPR_DEPTH>0
3676   void sqlite3ExprSetHeight(Parse *pParse, Expr *p);
3677   int sqlite3SelectExprHeight(Select *);
3678   int sqlite3ExprCheckHeight(Parse*, int);
3679 #else
3680   #define sqlite3ExprSetHeight(x,y)
3681   #define sqlite3SelectExprHeight(x) 0
3682   #define sqlite3ExprCheckHeight(x,y)
3683 #endif
3684 
3685 u32 sqlite3Get4byte(const u8*);
3686 void sqlite3Put4byte(u8*, u32);
3687 
3688 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
3689   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
3690   void sqlite3ConnectionUnlocked(sqlite3 *db);
3691   void sqlite3ConnectionClosed(sqlite3 *db);
3692 #else
3693   #define sqlite3ConnectionBlocked(x,y)
3694   #define sqlite3ConnectionUnlocked(x)
3695   #define sqlite3ConnectionClosed(x)
3696 #endif
3697 
3698 #ifdef SQLITE_DEBUG
3699   void sqlite3ParserTrace(FILE*, char *);
3700 #endif
3701 
3702 /*
3703 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
3704 ** sqlite3IoTrace is a pointer to a printf-like routine used to
3705 ** print I/O tracing messages.
3706 */
3707 #ifdef SQLITE_ENABLE_IOTRACE
3708 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
3709   void sqlite3VdbeIOTraceSql(Vdbe*);
3710 SQLITE_EXTERN void (*sqlite3IoTrace)(const char*,...);
3711 #else
3712 # define IOTRACE(A)
3713 # define sqlite3VdbeIOTraceSql(X)
3714 #endif
3715 
3716 /*
3717 ** These routines are available for the mem2.c debugging memory allocator
3718 ** only.  They are used to verify that different "types" of memory
3719 ** allocations are properly tracked by the system.
3720 **
3721 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
3722 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
3723 ** a single bit set.
3724 **
3725 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
3726 ** argument match the type set by the previous sqlite3MemdebugSetType().
3727 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
3728 **
3729 ** sqlite3MemdebugNoType() returns true if none of the bits in its second
3730 ** argument match the type set by the previous sqlite3MemdebugSetType().
3731 **
3732 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
3733 ** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
3734 ** it might have been allocated by lookaside, except the allocation was
3735 ** too large or lookaside was already full.  It is important to verify
3736 ** that allocations that might have been satisfied by lookaside are not
3737 ** passed back to non-lookaside free() routines.  Asserts such as the
3738 ** example above are placed on the non-lookaside free() routines to verify
3739 ** this constraint.
3740 **
3741 ** All of this is no-op for a production build.  It only comes into
3742 ** play when the SQLITE_MEMDEBUG compile-time option is used.
3743 */
3744 #ifdef SQLITE_MEMDEBUG
3745   void sqlite3MemdebugSetType(void*,u8);
3746   int sqlite3MemdebugHasType(void*,u8);
3747   int sqlite3MemdebugNoType(void*,u8);
3748 #else
3749 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
3750 # define sqlite3MemdebugHasType(X,Y)  1
3751 # define sqlite3MemdebugNoType(X,Y)   1
3752 #endif
3753 #define MEMTYPE_HEAP       0x01  /* General heap allocations */
3754 #define MEMTYPE_LOOKASIDE  0x02  /* Might have been lookaside memory */
3755 #define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
3756 #define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
3757 #define MEMTYPE_DB         0x10  /* Uses sqlite3DbMalloc, not sqlite_malloc */
3758 
3759 /*
3760 ** Threading interface
3761 */
3762 #if SQLITE_MAX_WORKER_THREADS>0
3763 int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
3764 int sqlite3ThreadJoin(SQLiteThread*, void**);
3765 #endif
3766 
3767 #endif /* _SQLITEINT_H_ */
3768