xref: /sqlite-3.40.0/src/sqliteInt.h (revision 48864df9)
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 ** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
36 */
37 #ifndef SQLITE_DISABLE_LFS
38 # define _LARGE_FILE       1
39 # ifndef _FILE_OFFSET_BITS
40 #   define _FILE_OFFSET_BITS 64
41 # endif
42 # define _LARGEFILE_SOURCE 1
43 #endif
44 
45 /*
46 ** Include the configuration header output by 'configure' if we're using the
47 ** autoconf-based build
48 */
49 #ifdef _HAVE_SQLITE_CONFIG_H
50 #include "config.h"
51 #endif
52 
53 #include "sqliteLimit.h"
54 
55 /* Disable nuisance warnings on Borland compilers */
56 #if defined(__BORLANDC__)
57 #pragma warn -rch /* unreachable code */
58 #pragma warn -ccc /* Condition is always true or false */
59 #pragma warn -aus /* Assigned value is never used */
60 #pragma warn -csu /* Comparing signed and unsigned */
61 #pragma warn -spa /* Suspicious pointer arithmetic */
62 #endif
63 
64 /* Needed for various definitions... */
65 #ifndef _GNU_SOURCE
66 # define _GNU_SOURCE
67 #endif
68 
69 #if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
70 # define _BSD_SOURCE
71 #endif
72 
73 /*
74 ** Include standard header files as necessary
75 */
76 #ifdef HAVE_STDINT_H
77 #include <stdint.h>
78 #endif
79 #ifdef HAVE_INTTYPES_H
80 #include <inttypes.h>
81 #endif
82 
83 /*
84 ** The following macros are used to cast pointers to integers and
85 ** integers to pointers.  The way you do this varies from one compiler
86 ** to the next, so we have developed the following set of #if statements
87 ** to generate appropriate macros for a wide range of compilers.
88 **
89 ** The correct "ANSI" way to do this is to use the intptr_t type.
90 ** Unfortunately, that typedef is not available on all compilers, or
91 ** if it is available, it requires an #include of specific headers
92 ** that vary from one machine to the next.
93 **
94 ** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
95 ** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
96 ** So we have to define the macros in different ways depending on the
97 ** compiler.
98 */
99 #if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
100 # define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
101 # define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
102 #elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
103 # define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
104 # define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
105 #elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
106 # define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
107 # define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
108 #else                          /* Generates a warning - but it always works */
109 # define SQLITE_INT_TO_PTR(X)  ((void*)(X))
110 # define SQLITE_PTR_TO_INT(X)  ((int)(X))
111 #endif
112 
113 /*
114 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
115 ** 0 means mutexes are permanently disable and the library is never
116 ** threadsafe.  1 means the library is serialized which is the highest
117 ** level of threadsafety.  2 means the libary is multithreaded - multiple
118 ** threads can use SQLite as long as no two threads try to use the same
119 ** database connection at the same time.
120 **
121 ** Older versions of SQLite used an optional THREADSAFE macro.
122 ** We support that for legacy.
123 */
124 #if !defined(SQLITE_THREADSAFE)
125 #if defined(THREADSAFE)
126 # define SQLITE_THREADSAFE THREADSAFE
127 #else
128 # define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
129 #endif
130 #endif
131 
132 /*
133 ** Powersafe overwrite is on by default.  But can be turned off using
134 ** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
135 */
136 #ifndef SQLITE_POWERSAFE_OVERWRITE
137 # define SQLITE_POWERSAFE_OVERWRITE 1
138 #endif
139 
140 /*
141 ** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
142 ** It determines whether or not the features related to
143 ** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
144 ** be overridden at runtime using the sqlite3_config() API.
145 */
146 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
147 # define SQLITE_DEFAULT_MEMSTATUS 1
148 #endif
149 
150 /*
151 ** Exactly one of the following macros must be defined in order to
152 ** specify which memory allocation subsystem to use.
153 **
154 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
155 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
156 **     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
157 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
158 **
159 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
160 ** assert() macro is enabled, each call into the Win32 native heap subsystem
161 ** will cause HeapValidate to be called.  If heap validation should fail, an
162 ** assertion will be triggered.
163 **
164 ** (Historical note:  There used to be several other options, but we've
165 ** pared it down to just these three.)
166 **
167 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
168 ** the default.
169 */
170 #if defined(SQLITE_SYSTEM_MALLOC) \
171   + defined(SQLITE_WIN32_MALLOC) \
172   + defined(SQLITE_ZERO_MALLOC) \
173   + defined(SQLITE_MEMDEBUG)>1
174 # error "Two or more of the following compile-time configuration options\
175  are defined but at most one is allowed:\
176  SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
177  SQLITE_ZERO_MALLOC"
178 #endif
179 #if defined(SQLITE_SYSTEM_MALLOC) \
180   + defined(SQLITE_WIN32_MALLOC) \
181   + defined(SQLITE_ZERO_MALLOC) \
182   + defined(SQLITE_MEMDEBUG)==0
183 # define SQLITE_SYSTEM_MALLOC 1
184 #endif
185 
186 /*
187 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
188 ** sizes of memory allocations below this value where possible.
189 */
190 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
191 # define SQLITE_MALLOC_SOFT_LIMIT 1024
192 #endif
193 
194 /*
195 ** We need to define _XOPEN_SOURCE as follows in order to enable
196 ** recursive mutexes on most Unix systems.  But Mac OS X is different.
197 ** The _XOPEN_SOURCE define causes problems for Mac OS X we are told,
198 ** so it is omitted there.  See ticket #2673.
199 **
200 ** Later we learn that _XOPEN_SOURCE is poorly or incorrectly
201 ** implemented on some systems.  So we avoid defining it at all
202 ** if it is already defined or if it is unneeded because we are
203 ** not doing a threadsafe build.  Ticket #2681.
204 **
205 ** See also ticket #2741.
206 */
207 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) \
208  && !defined(__APPLE__) && SQLITE_THREADSAFE
209 #  define _XOPEN_SOURCE 500  /* Needed to enable pthread recursive mutexes */
210 #endif
211 
212 /*
213 ** The TCL headers are only needed when compiling the TCL bindings.
214 */
215 #if defined(SQLITE_TCL) || defined(TCLSH)
216 # include <tcl.h>
217 #endif
218 
219 /*
220 ** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
221 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
222 ** make it true by defining or undefining NDEBUG.
223 **
224 ** Setting NDEBUG makes the code smaller and run faster by disabling the
225 ** number assert() statements in the code.  So we want the default action
226 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
227 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
228 ** feature.
229 */
230 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
231 # define NDEBUG 1
232 #endif
233 #if defined(NDEBUG) && defined(SQLITE_DEBUG)
234 # undef NDEBUG
235 #endif
236 
237 /*
238 ** The testcase() macro is used to aid in coverage testing.  When
239 ** doing coverage testing, the condition inside the argument to
240 ** testcase() must be evaluated both true and false in order to
241 ** get full branch coverage.  The testcase() macro is inserted
242 ** to help ensure adequate test coverage in places where simple
243 ** condition/decision coverage is inadequate.  For example, testcase()
244 ** can be used to make sure boundary values are tested.  For
245 ** bitmask tests, testcase() can be used to make sure each bit
246 ** is significant and used at least once.  On switch statements
247 ** where multiple cases go to the same block of code, testcase()
248 ** can insure that all cases are evaluated.
249 **
250 */
251 #ifdef SQLITE_COVERAGE_TEST
252   void sqlite3Coverage(int);
253 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
254 #else
255 # define testcase(X)
256 #endif
257 
258 /*
259 ** The TESTONLY macro is used to enclose variable declarations or
260 ** other bits of code that are needed to support the arguments
261 ** within testcase() and assert() macros.
262 */
263 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
264 # define TESTONLY(X)  X
265 #else
266 # define TESTONLY(X)
267 #endif
268 
269 /*
270 ** Sometimes we need a small amount of code such as a variable initialization
271 ** to setup for a later assert() statement.  We do not want this code to
272 ** appear when assert() is disabled.  The following macro is therefore
273 ** used to contain that setup code.  The "VVA" acronym stands for
274 ** "Verification, Validation, and Accreditation".  In other words, the
275 ** code within VVA_ONLY() will only run during verification processes.
276 */
277 #ifndef NDEBUG
278 # define VVA_ONLY(X)  X
279 #else
280 # define VVA_ONLY(X)
281 #endif
282 
283 /*
284 ** The ALWAYS and NEVER macros surround boolean expressions which
285 ** are intended to always be true or false, respectively.  Such
286 ** expressions could be omitted from the code completely.  But they
287 ** are included in a few cases in order to enhance the resilience
288 ** of SQLite to unexpected behavior - to make the code "self-healing"
289 ** or "ductile" rather than being "brittle" and crashing at the first
290 ** hint of unplanned behavior.
291 **
292 ** In other words, ALWAYS and NEVER are added for defensive code.
293 **
294 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
295 ** be true and false so that the unreachable code then specify will
296 ** not be counted as untested code.
297 */
298 #if defined(SQLITE_COVERAGE_TEST)
299 # define ALWAYS(X)      (1)
300 # define NEVER(X)       (0)
301 #elif !defined(NDEBUG)
302 # define ALWAYS(X)      ((X)?1:(assert(0),0))
303 # define NEVER(X)       ((X)?(assert(0),1):0)
304 #else
305 # define ALWAYS(X)      (X)
306 # define NEVER(X)       (X)
307 #endif
308 
309 /*
310 ** Return true (non-zero) if the input is a integer that is too large
311 ** to fit in 32-bits.  This macro is used inside of various testcase()
312 ** macros to verify that we have tested SQLite for large-file support.
313 */
314 #define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
315 
316 /*
317 ** The macro unlikely() is a hint that surrounds a boolean
318 ** expression that is usually false.  Macro likely() surrounds
319 ** a boolean expression that is usually true.  GCC is able to
320 ** use these hints to generate better code, sometimes.
321 */
322 #if defined(__GNUC__) && 0
323 # define likely(X)    __builtin_expect((X),1)
324 # define unlikely(X)  __builtin_expect((X),0)
325 #else
326 # define likely(X)    !!(X)
327 # define unlikely(X)  !!(X)
328 #endif
329 
330 #include "sqlite3.h"
331 #include "hash.h"
332 #include "parse.h"
333 #include <stdio.h>
334 #include <stdlib.h>
335 #include <string.h>
336 #include <assert.h>
337 #include <stddef.h>
338 
339 /*
340 ** If compiling for a processor that lacks floating point support,
341 ** substitute integer for floating-point
342 */
343 #ifdef SQLITE_OMIT_FLOATING_POINT
344 # define double sqlite_int64
345 # define float sqlite_int64
346 # define LONGDOUBLE_TYPE sqlite_int64
347 # ifndef SQLITE_BIG_DBL
348 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
349 # endif
350 # define SQLITE_OMIT_DATETIME_FUNCS 1
351 # define SQLITE_OMIT_TRACE 1
352 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
353 # undef SQLITE_HAVE_ISNAN
354 #endif
355 #ifndef SQLITE_BIG_DBL
356 # define SQLITE_BIG_DBL (1e99)
357 #endif
358 
359 /*
360 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
361 ** afterward. Having this macro allows us to cause the C compiler
362 ** to omit code used by TEMP tables without messy #ifndef statements.
363 */
364 #ifdef SQLITE_OMIT_TEMPDB
365 #define OMIT_TEMPDB 1
366 #else
367 #define OMIT_TEMPDB 0
368 #endif
369 
370 /*
371 ** The "file format" number is an integer that is incremented whenever
372 ** the VDBE-level file format changes.  The following macros define the
373 ** the default file format for new databases and the maximum file format
374 ** that the library can read.
375 */
376 #define SQLITE_MAX_FILE_FORMAT 4
377 #ifndef SQLITE_DEFAULT_FILE_FORMAT
378 # define SQLITE_DEFAULT_FILE_FORMAT 4
379 #endif
380 
381 /*
382 ** Determine whether triggers are recursive by default.  This can be
383 ** changed at run-time using a pragma.
384 */
385 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
386 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
387 #endif
388 
389 /*
390 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
391 ** on the command-line
392 */
393 #ifndef SQLITE_TEMP_STORE
394 # define SQLITE_TEMP_STORE 1
395 #endif
396 
397 /*
398 ** GCC does not define the offsetof() macro so we'll have to do it
399 ** ourselves.
400 */
401 #ifndef offsetof
402 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
403 #endif
404 
405 /*
406 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
407 ** not, there are still machines out there that use EBCDIC.)
408 */
409 #if 'A' == '\301'
410 # define SQLITE_EBCDIC 1
411 #else
412 # define SQLITE_ASCII 1
413 #endif
414 
415 /*
416 ** Integers of known sizes.  These typedefs might change for architectures
417 ** where the sizes very.  Preprocessor macros are available so that the
418 ** types can be conveniently redefined at compile-type.  Like this:
419 **
420 **         cc '-DUINTPTR_TYPE=long long int' ...
421 */
422 #ifndef UINT32_TYPE
423 # ifdef HAVE_UINT32_T
424 #  define UINT32_TYPE uint32_t
425 # else
426 #  define UINT32_TYPE unsigned int
427 # endif
428 #endif
429 #ifndef UINT16_TYPE
430 # ifdef HAVE_UINT16_T
431 #  define UINT16_TYPE uint16_t
432 # else
433 #  define UINT16_TYPE unsigned short int
434 # endif
435 #endif
436 #ifndef INT16_TYPE
437 # ifdef HAVE_INT16_T
438 #  define INT16_TYPE int16_t
439 # else
440 #  define INT16_TYPE short int
441 # endif
442 #endif
443 #ifndef UINT8_TYPE
444 # ifdef HAVE_UINT8_T
445 #  define UINT8_TYPE uint8_t
446 # else
447 #  define UINT8_TYPE unsigned char
448 # endif
449 #endif
450 #ifndef INT8_TYPE
451 # ifdef HAVE_INT8_T
452 #  define INT8_TYPE int8_t
453 # else
454 #  define INT8_TYPE signed char
455 # endif
456 #endif
457 #ifndef LONGDOUBLE_TYPE
458 # define LONGDOUBLE_TYPE long double
459 #endif
460 typedef sqlite_int64 i64;          /* 8-byte signed integer */
461 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
462 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
463 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
464 typedef INT16_TYPE i16;            /* 2-byte signed integer */
465 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
466 typedef INT8_TYPE i8;              /* 1-byte signed integer */
467 
468 /*
469 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
470 ** that can be stored in a u32 without loss of data.  The value
471 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
472 ** have to specify the value in the less intuitive manner shown:
473 */
474 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
475 
476 /*
477 ** The datatype used to store estimates of the number of rows in a
478 ** table or index.  This is an unsigned integer type.  For 99.9% of
479 ** the world, a 32-bit integer is sufficient.  But a 64-bit integer
480 ** can be used at compile-time if desired.
481 */
482 #ifdef SQLITE_64BIT_STATS
483  typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
484 #else
485  typedef u32 tRowcnt;    /* 32-bit is the default */
486 #endif
487 
488 /*
489 ** Macros to determine whether the machine is big or little endian,
490 ** evaluated at runtime.
491 */
492 #ifdef SQLITE_AMALGAMATION
493 const int sqlite3one = 1;
494 #else
495 extern const int sqlite3one;
496 #endif
497 #if defined(i386) || defined(__i386__) || defined(_M_IX86)\
498                              || defined(__x86_64) || defined(__x86_64__)
499 # define SQLITE_BIGENDIAN    0
500 # define SQLITE_LITTLEENDIAN 1
501 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
502 #else
503 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
504 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
505 # define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
506 #endif
507 
508 /*
509 ** Constants for the largest and smallest possible 64-bit signed integers.
510 ** These macros are designed to work correctly on both 32-bit and 64-bit
511 ** compilers.
512 */
513 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
514 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
515 
516 /*
517 ** Round up a number to the next larger multiple of 8.  This is used
518 ** to force 8-byte alignment on 64-bit architectures.
519 */
520 #define ROUND8(x)     (((x)+7)&~7)
521 
522 /*
523 ** Round down to the nearest multiple of 8
524 */
525 #define ROUNDDOWN8(x) ((x)&~7)
526 
527 /*
528 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
529 ** macro is used only within assert() to verify that the code gets
530 ** all alignment restrictions correct.
531 **
532 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
533 ** underlying malloc() implemention might return us 4-byte aligned
534 ** pointers.  In that case, only verify 4-byte alignment.
535 */
536 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
537 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
538 #else
539 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
540 #endif
541 
542 
543 /*
544 ** An instance of the following structure is used to store the busy-handler
545 ** callback for a given sqlite handle.
546 **
547 ** The sqlite.busyHandler member of the sqlite struct contains the busy
548 ** callback for the database handle. Each pager opened via the sqlite
549 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
550 ** callback is currently invoked only from within pager.c.
551 */
552 typedef struct BusyHandler BusyHandler;
553 struct BusyHandler {
554   int (*xFunc)(void *,int);  /* The busy callback */
555   void *pArg;                /* First arg to busy callback */
556   int nBusy;                 /* Incremented with each busy call */
557 };
558 
559 /*
560 ** Name of the master database table.  The master database table
561 ** is a special table that holds the names and attributes of all
562 ** user tables and indices.
563 */
564 #define MASTER_NAME       "sqlite_master"
565 #define TEMP_MASTER_NAME  "sqlite_temp_master"
566 
567 /*
568 ** The root-page of the master database table.
569 */
570 #define MASTER_ROOT       1
571 
572 /*
573 ** The name of the schema table.
574 */
575 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
576 
577 /*
578 ** A convenience macro that returns the number of elements in
579 ** an array.
580 */
581 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
582 
583 /*
584 ** Determine if the argument is a power of two
585 */
586 #define IsPowerOfTwo(X) (((X)&((X)-1))==0)
587 
588 /*
589 ** The following value as a destructor means to use sqlite3DbFree().
590 ** The sqlite3DbFree() routine requires two parameters instead of the
591 ** one parameter that destructors normally want.  So we have to introduce
592 ** this magic value that the code knows to handle differently.  Any
593 ** pointer will work here as long as it is distinct from SQLITE_STATIC
594 ** and SQLITE_TRANSIENT.
595 */
596 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3MallocSize)
597 
598 /*
599 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
600 ** not support Writable Static Data (WSD) such as global and static variables.
601 ** All variables must either be on the stack or dynamically allocated from
602 ** the heap.  When WSD is unsupported, the variable declarations scattered
603 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
604 ** macro is used for this purpose.  And instead of referencing the variable
605 ** directly, we use its constant as a key to lookup the run-time allocated
606 ** buffer that holds real variable.  The constant is also the initializer
607 ** for the run-time allocated buffer.
608 **
609 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
610 ** macros become no-ops and have zero performance impact.
611 */
612 #ifdef SQLITE_OMIT_WSD
613   #define SQLITE_WSD const
614   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
615   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
616   int sqlite3_wsd_init(int N, int J);
617   void *sqlite3_wsd_find(void *K, int L);
618 #else
619   #define SQLITE_WSD
620   #define GLOBAL(t,v) v
621   #define sqlite3GlobalConfig sqlite3Config
622 #endif
623 
624 /*
625 ** The following macros are used to suppress compiler warnings and to
626 ** make it clear to human readers when a function parameter is deliberately
627 ** left unused within the body of a function. This usually happens when
628 ** a function is called via a function pointer. For example the
629 ** implementation of an SQL aggregate step callback may not use the
630 ** parameter indicating the number of arguments passed to the aggregate,
631 ** if it knows that this is enforced elsewhere.
632 **
633 ** When a function parameter is not used at all within the body of a function,
634 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
635 ** However, these macros may also be used to suppress warnings related to
636 ** parameters that may or may not be used depending on compilation options.
637 ** For example those parameters only used in assert() statements. In these
638 ** cases the parameters are named as per the usual conventions.
639 */
640 #define UNUSED_PARAMETER(x) (void)(x)
641 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
642 
643 /*
644 ** Forward references to structures
645 */
646 typedef struct AggInfo AggInfo;
647 typedef struct AuthContext AuthContext;
648 typedef struct AutoincInfo AutoincInfo;
649 typedef struct Bitvec Bitvec;
650 typedef struct CollSeq CollSeq;
651 typedef struct Column Column;
652 typedef struct Db Db;
653 typedef struct Schema Schema;
654 typedef struct Expr Expr;
655 typedef struct ExprList ExprList;
656 typedef struct ExprSpan ExprSpan;
657 typedef struct FKey FKey;
658 typedef struct FuncDestructor FuncDestructor;
659 typedef struct FuncDef FuncDef;
660 typedef struct FuncDefHash FuncDefHash;
661 typedef struct IdList IdList;
662 typedef struct Index Index;
663 typedef struct IndexSample IndexSample;
664 typedef struct KeyClass KeyClass;
665 typedef struct KeyInfo KeyInfo;
666 typedef struct Lookaside Lookaside;
667 typedef struct LookasideSlot LookasideSlot;
668 typedef struct Module Module;
669 typedef struct NameContext NameContext;
670 typedef struct Parse Parse;
671 typedef struct RowSet RowSet;
672 typedef struct Savepoint Savepoint;
673 typedef struct Select Select;
674 typedef struct SelectDest SelectDest;
675 typedef struct SrcList SrcList;
676 typedef struct StrAccum StrAccum;
677 typedef struct Table Table;
678 typedef struct TableLock TableLock;
679 typedef struct Token Token;
680 typedef struct Trigger Trigger;
681 typedef struct TriggerPrg TriggerPrg;
682 typedef struct TriggerStep TriggerStep;
683 typedef struct UnpackedRecord UnpackedRecord;
684 typedef struct VTable VTable;
685 typedef struct VtabCtx VtabCtx;
686 typedef struct Walker Walker;
687 typedef struct WherePlan WherePlan;
688 typedef struct WhereInfo WhereInfo;
689 typedef struct WhereLevel WhereLevel;
690 
691 /*
692 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
693 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
694 ** pointer types (i.e. FuncDef) defined above.
695 */
696 #include "btree.h"
697 #include "vdbe.h"
698 #include "pager.h"
699 #include "pcache.h"
700 
701 #include "os.h"
702 #include "mutex.h"
703 
704 
705 /*
706 ** Each database file to be accessed by the system is an instance
707 ** of the following structure.  There are normally two of these structures
708 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
709 ** aDb[1] is the database file used to hold temporary tables.  Additional
710 ** databases may be attached.
711 */
712 struct Db {
713   char *zName;         /* Name of this database */
714   Btree *pBt;          /* The B*Tree structure for this database file */
715   u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
716   u8 safety_level;     /* How aggressive at syncing data to disk */
717   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
718 };
719 
720 /*
721 ** An instance of the following structure stores a database schema.
722 **
723 ** Most Schema objects are associated with a Btree.  The exception is
724 ** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
725 ** In shared cache mode, a single Schema object can be shared by multiple
726 ** Btrees that refer to the same underlying BtShared object.
727 **
728 ** Schema objects are automatically deallocated when the last Btree that
729 ** references them is destroyed.   The TEMP Schema is manually freed by
730 ** sqlite3_close().
731 *
732 ** A thread must be holding a mutex on the corresponding Btree in order
733 ** to access Schema content.  This implies that the thread must also be
734 ** holding a mutex on the sqlite3 connection pointer that owns the Btree.
735 ** For a TEMP Schema, only the connection mutex is required.
736 */
737 struct Schema {
738   int schema_cookie;   /* Database schema version number for this file */
739   int iGeneration;     /* Generation counter.  Incremented with each change */
740   Hash tblHash;        /* All tables indexed by name */
741   Hash idxHash;        /* All (named) indices indexed by name */
742   Hash trigHash;       /* All triggers indexed by name */
743   Hash fkeyHash;       /* All foreign keys by referenced table name */
744   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
745   u8 file_format;      /* Schema format version for this file */
746   u8 enc;              /* Text encoding used by this database */
747   u16 flags;           /* Flags associated with this schema */
748   int cache_size;      /* Number of pages to use in the cache */
749 };
750 
751 /*
752 ** These macros can be used to test, set, or clear bits in the
753 ** Db.pSchema->flags field.
754 */
755 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->flags&(P))==(P))
756 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->flags&(P))!=0)
757 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->flags|=(P)
758 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->flags&=~(P)
759 
760 /*
761 ** Allowed values for the DB.pSchema->flags field.
762 **
763 ** The DB_SchemaLoaded flag is set after the database schema has been
764 ** read into internal hash tables.
765 **
766 ** DB_UnresetViews means that one or more views have column names that
767 ** have been filled out.  If the schema changes, these column names might
768 ** changes and so the view will need to be reset.
769 */
770 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
771 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
772 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
773 
774 /*
775 ** The number of different kinds of things that can be limited
776 ** using the sqlite3_limit() interface.
777 */
778 #define SQLITE_N_LIMIT (SQLITE_LIMIT_TRIGGER_DEPTH+1)
779 
780 /*
781 ** Lookaside malloc is a set of fixed-size buffers that can be used
782 ** to satisfy small transient memory allocation requests for objects
783 ** associated with a particular database connection.  The use of
784 ** lookaside malloc provides a significant performance enhancement
785 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
786 ** SQL statements.
787 **
788 ** The Lookaside structure holds configuration information about the
789 ** lookaside malloc subsystem.  Each available memory allocation in
790 ** the lookaside subsystem is stored on a linked list of LookasideSlot
791 ** objects.
792 **
793 ** Lookaside allocations are only allowed for objects that are associated
794 ** with a particular database connection.  Hence, schema information cannot
795 ** be stored in lookaside because in shared cache mode the schema information
796 ** is shared by multiple database connections.  Therefore, while parsing
797 ** schema information, the Lookaside.bEnabled flag is cleared so that
798 ** lookaside allocations are not used to construct the schema objects.
799 */
800 struct Lookaside {
801   u16 sz;                 /* Size of each buffer in bytes */
802   u8 bEnabled;            /* False to disable new lookaside allocations */
803   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
804   int nOut;               /* Number of buffers currently checked out */
805   int mxOut;              /* Highwater mark for nOut */
806   int anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
807   LookasideSlot *pFree;   /* List of available buffers */
808   void *pStart;           /* First byte of available memory space */
809   void *pEnd;             /* First byte past end of available space */
810 };
811 struct LookasideSlot {
812   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
813 };
814 
815 /*
816 ** A hash table for function definitions.
817 **
818 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
819 ** Collisions are on the FuncDef.pHash chain.
820 */
821 struct FuncDefHash {
822   FuncDef *a[23];       /* Hash table for functions */
823 };
824 
825 /*
826 ** Each database connection is an instance of the following structure.
827 */
828 struct sqlite3 {
829   sqlite3_vfs *pVfs;            /* OS Interface */
830   struct Vdbe *pVdbe;           /* List of active virtual machines */
831   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
832   sqlite3_mutex *mutex;         /* Connection mutex */
833   Db *aDb;                      /* All backends */
834   int nDb;                      /* Number of backends currently in use */
835   int flags;                    /* Miscellaneous flags. See below */
836   i64 lastRowid;                /* ROWID of most recent insert (see above) */
837   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
838   int errCode;                  /* Most recent error code (SQLITE_*) */
839   int errMask;                  /* & result codes with this before returning */
840   u16 dbOptFlags;               /* Flags to enable/disable optimizations */
841   u8 autoCommit;                /* The auto-commit flag. */
842   u8 temp_store;                /* 1: file 2: memory 0: default */
843   u8 mallocFailed;              /* True if we have seen a malloc failure */
844   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
845   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
846   u8 suppressErr;               /* Do not issue error messages if true */
847   u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
848   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
849   int nextPagesize;             /* Pagesize after VACUUM if >0 */
850   u32 magic;                    /* Magic number for detect library misuse */
851   int nChange;                  /* Value returned by sqlite3_changes() */
852   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
853   int aLimit[SQLITE_N_LIMIT];   /* Limits */
854   struct sqlite3InitInfo {      /* Information used during initialization */
855     int newTnum;                /* Rootpage of table being initialized */
856     u8 iDb;                     /* Which db file is being initialized */
857     u8 busy;                    /* TRUE if currently initializing */
858     u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
859   } init;
860   int activeVdbeCnt;            /* Number of VDBEs currently executing */
861   int writeVdbeCnt;             /* Number of active VDBEs that are writing */
862   int vdbeExecCnt;              /* Number of nested calls to VdbeExec() */
863   int nExtension;               /* Number of loaded extensions */
864   void **aExtension;            /* Array of shared library handles */
865   void (*xTrace)(void*,const char*);        /* Trace function */
866   void *pTraceArg;                          /* Argument to the trace function */
867   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
868   void *pProfileArg;                        /* Argument to profile function */
869   void *pCommitArg;                 /* Argument to xCommitCallback() */
870   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
871   void *pRollbackArg;               /* Argument to xRollbackCallback() */
872   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
873   void *pUpdateArg;
874   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
875 #ifndef SQLITE_OMIT_WAL
876   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
877   void *pWalArg;
878 #endif
879   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
880   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
881   void *pCollNeededArg;
882   sqlite3_value *pErr;          /* Most recent error message */
883   char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
884   char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
885   union {
886     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
887     double notUsed1;            /* Spacer */
888   } u1;
889   Lookaside lookaside;          /* Lookaside malloc configuration */
890 #ifndef SQLITE_OMIT_AUTHORIZATION
891   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
892                                 /* Access authorization function */
893   void *pAuthArg;               /* 1st argument to the access auth function */
894 #endif
895 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
896   int (*xProgress)(void *);     /* The progress callback */
897   void *pProgressArg;           /* Argument to the progress callback */
898   int nProgressOps;             /* Number of opcodes for progress callback */
899 #endif
900 #ifndef SQLITE_OMIT_VIRTUALTABLE
901   int nVTrans;                  /* Allocated size of aVTrans */
902   Hash aModule;                 /* populated by sqlite3_create_module() */
903   VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
904   VTable **aVTrans;             /* Virtual tables with open transactions */
905   VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
906 #endif
907   FuncDefHash aFunc;            /* Hash table of connection functions */
908   Hash aCollSeq;                /* All collating sequences */
909   BusyHandler busyHandler;      /* Busy callback */
910   Db aDbStatic[2];              /* Static space for the 2 default backends */
911   Savepoint *pSavepoint;        /* List of active savepoints */
912   int busyTimeout;              /* Busy handler timeout, in msec */
913   int nSavepoint;               /* Number of non-transaction savepoints */
914   int nStatement;               /* Number of nested statement-transactions  */
915   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
916   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
917 
918 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
919   /* The following variables are all protected by the STATIC_MASTER
920   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
921   **
922   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
923   ** unlock so that it can proceed.
924   **
925   ** When X.pBlockingConnection==Y, that means that something that X tried
926   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
927   ** held by Y.
928   */
929   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
930   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
931   void *pUnlockArg;                     /* Argument to xUnlockNotify */
932   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
933   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
934 #endif
935 };
936 
937 /*
938 ** A macro to discover the encoding of a database.
939 */
940 #define ENC(db) ((db)->aDb[0].pSchema->enc)
941 
942 /*
943 ** Possible values for the sqlite3.flags.
944 */
945 #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
946 #define SQLITE_InternChanges  0x00000002  /* Uncommitted Hash table changes */
947 #define SQLITE_FullColNames   0x00000004  /* Show full column names on SELECT */
948 #define SQLITE_ShortColNames  0x00000008  /* Show short columns names */
949 #define SQLITE_CountRows      0x00000010  /* Count rows changed by INSERT, */
950                                           /*   DELETE, or UPDATE and return */
951                                           /*   the count using a callback. */
952 #define SQLITE_NullCallback   0x00000020  /* Invoke the callback once if the */
953                                           /*   result set is empty */
954 #define SQLITE_SqlTrace       0x00000040  /* Debug print SQL as it executes */
955 #define SQLITE_VdbeListing    0x00000080  /* Debug listings of VDBE programs */
956 #define SQLITE_WriteSchema    0x00000100  /* OK to update SQLITE_MASTER */
957 #define SQLITE_VdbeAddopTrace 0x00000200  /* Trace sqlite3VdbeAddOp() calls */
958 #define SQLITE_IgnoreChecks   0x00000400  /* Do not enforce check constraints */
959 #define SQLITE_ReadUncommitted 0x0000800  /* For shared-cache mode */
960 #define SQLITE_LegacyFileFmt  0x00001000  /* Create new databases in format 1 */
961 #define SQLITE_FullFSync      0x00002000  /* Use full fsync on the backend */
962 #define SQLITE_CkptFullFSync  0x00004000  /* Use full fsync for checkpoint */
963 #define SQLITE_RecoveryMode   0x00008000  /* Ignore schema errors */
964 #define SQLITE_ReverseOrder   0x00010000  /* Reverse unordered SELECTs */
965 #define SQLITE_RecTriggers    0x00020000  /* Enable recursive triggers */
966 #define SQLITE_ForeignKeys    0x00040000  /* Enforce foreign key constraints  */
967 #define SQLITE_AutoIndex      0x00080000  /* Enable automatic indexes */
968 #define SQLITE_PreferBuiltin  0x00100000  /* Preference to built-in funcs */
969 #define SQLITE_LoadExtension  0x00200000  /* Enable load_extension */
970 #define SQLITE_EnableTrigger  0x00400000  /* True to enable triggers */
971 
972 /*
973 ** Bits of the sqlite3.dbOptFlags field that are used by the
974 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
975 ** selectively disable various optimizations.
976 */
977 #define SQLITE_QueryFlattener 0x0001   /* Query flattening */
978 #define SQLITE_ColumnCache    0x0002   /* Column cache */
979 #define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
980 #define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
981 #define SQLITE_IdxRealAsInt   0x0010   /* Store REAL as INT in indices */
982 #define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
983 #define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
984 #define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
985 #define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
986 #define SQLITE_Transitive     0x0200   /* Transitive constraints */
987 #define SQLITE_AllOpts        0xffff   /* All optimizations */
988 
989 /*
990 ** Macros for testing whether or not optimizations are enabled or disabled.
991 */
992 #ifndef SQLITE_OMIT_BUILTIN_TEST
993 #define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
994 #define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
995 #else
996 #define OptimizationDisabled(db, mask)  0
997 #define OptimizationEnabled(db, mask)   1
998 #endif
999 
1000 /*
1001 ** Possible values for the sqlite.magic field.
1002 ** The numbers are obtained at random and have no special meaning, other
1003 ** than being distinct from one another.
1004 */
1005 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
1006 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
1007 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
1008 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
1009 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
1010 #define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */
1011 
1012 /*
1013 ** Each SQL function is defined by an instance of the following
1014 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
1015 ** hash table.  When multiple functions have the same name, the hash table
1016 ** points to a linked list of these structures.
1017 */
1018 struct FuncDef {
1019   i16 nArg;            /* Number of arguments.  -1 means unlimited */
1020   u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
1021   u8 flags;            /* Some combination of SQLITE_FUNC_* */
1022   void *pUserData;     /* User data parameter */
1023   FuncDef *pNext;      /* Next function with same name */
1024   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
1025   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
1026   void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
1027   char *zName;         /* SQL name of the function. */
1028   FuncDef *pHash;      /* Next with a different name but the same hash */
1029   FuncDestructor *pDestructor;   /* Reference counted destructor function */
1030 };
1031 
1032 /*
1033 ** This structure encapsulates a user-function destructor callback (as
1034 ** configured using create_function_v2()) and a reference counter. When
1035 ** create_function_v2() is called to create a function with a destructor,
1036 ** a single object of this type is allocated. FuncDestructor.nRef is set to
1037 ** the number of FuncDef objects created (either 1 or 3, depending on whether
1038 ** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
1039 ** member of each of the new FuncDef objects is set to point to the allocated
1040 ** FuncDestructor.
1041 **
1042 ** Thereafter, when one of the FuncDef objects is deleted, the reference
1043 ** count on this object is decremented. When it reaches 0, the destructor
1044 ** is invoked and the FuncDestructor structure freed.
1045 */
1046 struct FuncDestructor {
1047   int nRef;
1048   void (*xDestroy)(void *);
1049   void *pUserData;
1050 };
1051 
1052 /*
1053 ** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
1054 ** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  There
1055 ** are assert() statements in the code to verify this.
1056 */
1057 #define SQLITE_FUNC_LIKE     0x01 /* Candidate for the LIKE optimization */
1058 #define SQLITE_FUNC_CASE     0x02 /* Case-sensitive LIKE-type function */
1059 #define SQLITE_FUNC_EPHEM    0x04 /* Ephemeral.  Delete with VDBE */
1060 #define SQLITE_FUNC_NEEDCOLL 0x08 /* sqlite3GetFuncCollSeq() might be called */
1061 #define SQLITE_FUNC_COUNT    0x10 /* Built-in count(*) aggregate */
1062 #define SQLITE_FUNC_COALESCE 0x20 /* Built-in coalesce() or ifnull() function */
1063 #define SQLITE_FUNC_LENGTH   0x40 /* Built-in length() function */
1064 #define SQLITE_FUNC_TYPEOF   0x80 /* Built-in typeof() function */
1065 
1066 /*
1067 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
1068 ** used to create the initializers for the FuncDef structures.
1069 **
1070 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
1071 **     Used to create a scalar function definition of a function zName
1072 **     implemented by C function xFunc that accepts nArg arguments. The
1073 **     value passed as iArg is cast to a (void*) and made available
1074 **     as the user-data (sqlite3_user_data()) for the function. If
1075 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
1076 **
1077 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
1078 **     Used to create an aggregate function definition implemented by
1079 **     the C functions xStep and xFinal. The first four parameters
1080 **     are interpreted in the same way as the first 4 parameters to
1081 **     FUNCTION().
1082 **
1083 **   LIKEFUNC(zName, nArg, pArg, flags)
1084 **     Used to create a scalar function definition of a function zName
1085 **     that accepts nArg arguments and is implemented by a call to C
1086 **     function likeFunc. Argument pArg is cast to a (void *) and made
1087 **     available as the function user-data (sqlite3_user_data()). The
1088 **     FuncDef.flags variable is set to the value passed as the flags
1089 **     parameter.
1090 */
1091 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1092   {nArg, SQLITE_UTF8, (bNC*SQLITE_FUNC_NEEDCOLL), \
1093    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1094 #define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
1095   {nArg, SQLITE_UTF8, (bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags, \
1096    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
1097 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
1098   {nArg, SQLITE_UTF8, bNC*SQLITE_FUNC_NEEDCOLL, \
1099    pArg, 0, xFunc, 0, 0, #zName, 0, 0}
1100 #define LIKEFUNC(zName, nArg, arg, flags) \
1101   {nArg, SQLITE_UTF8, flags, (void *)arg, 0, likeFunc, 0, 0, #zName, 0, 0}
1102 #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
1103   {nArg, SQLITE_UTF8, nc*SQLITE_FUNC_NEEDCOLL, \
1104    SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}
1105 
1106 /*
1107 ** All current savepoints are stored in a linked list starting at
1108 ** sqlite3.pSavepoint. The first element in the list is the most recently
1109 ** opened savepoint. Savepoints are added to the list by the vdbe
1110 ** OP_Savepoint instruction.
1111 */
1112 struct Savepoint {
1113   char *zName;                        /* Savepoint name (nul-terminated) */
1114   i64 nDeferredCons;                  /* Number of deferred fk violations */
1115   Savepoint *pNext;                   /* Parent savepoint (if any) */
1116 };
1117 
1118 /*
1119 ** The following are used as the second parameter to sqlite3Savepoint(),
1120 ** and as the P1 argument to the OP_Savepoint instruction.
1121 */
1122 #define SAVEPOINT_BEGIN      0
1123 #define SAVEPOINT_RELEASE    1
1124 #define SAVEPOINT_ROLLBACK   2
1125 
1126 
1127 /*
1128 ** Each SQLite module (virtual table definition) is defined by an
1129 ** instance of the following structure, stored in the sqlite3.aModule
1130 ** hash table.
1131 */
1132 struct Module {
1133   const sqlite3_module *pModule;       /* Callback pointers */
1134   const char *zName;                   /* Name passed to create_module() */
1135   void *pAux;                          /* pAux passed to create_module() */
1136   void (*xDestroy)(void *);            /* Module destructor function */
1137 };
1138 
1139 /*
1140 ** information about each column of an SQL table is held in an instance
1141 ** of this structure.
1142 */
1143 struct Column {
1144   char *zName;     /* Name of this column */
1145   Expr *pDflt;     /* Default value of this column */
1146   char *zDflt;     /* Original text of the default value */
1147   char *zType;     /* Data type for this column */
1148   char *zColl;     /* Collating sequence.  If NULL, use the default */
1149   u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
1150   char affinity;   /* One of the SQLITE_AFF_... values */
1151   u16 colFlags;    /* Boolean properties.  See COLFLAG_ defines below */
1152 };
1153 
1154 /* Allowed values for Column.colFlags:
1155 */
1156 #define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
1157 #define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */
1158 
1159 /*
1160 ** A "Collating Sequence" is defined by an instance of the following
1161 ** structure. Conceptually, a collating sequence consists of a name and
1162 ** a comparison routine that defines the order of that sequence.
1163 **
1164 ** If CollSeq.xCmp is NULL, it means that the
1165 ** collating sequence is undefined.  Indices built on an undefined
1166 ** collating sequence may not be read or written.
1167 */
1168 struct CollSeq {
1169   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
1170   u8 enc;               /* Text encoding handled by xCmp() */
1171   void *pUser;          /* First argument to xCmp() */
1172   int (*xCmp)(void*,int, const void*, int, const void*);
1173   void (*xDel)(void*);  /* Destructor for pUser */
1174 };
1175 
1176 /*
1177 ** A sort order can be either ASC or DESC.
1178 */
1179 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
1180 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
1181 
1182 /*
1183 ** Column affinity types.
1184 **
1185 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
1186 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
1187 ** the speed a little by numbering the values consecutively.
1188 **
1189 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
1190 ** when multiple affinity types are concatenated into a string and
1191 ** used as the P4 operand, they will be more readable.
1192 **
1193 ** Note also that the numeric types are grouped together so that testing
1194 ** for a numeric type is a single comparison.
1195 */
1196 #define SQLITE_AFF_TEXT     'a'
1197 #define SQLITE_AFF_NONE     'b'
1198 #define SQLITE_AFF_NUMERIC  'c'
1199 #define SQLITE_AFF_INTEGER  'd'
1200 #define SQLITE_AFF_REAL     'e'
1201 
1202 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
1203 
1204 /*
1205 ** The SQLITE_AFF_MASK values masks off the significant bits of an
1206 ** affinity value.
1207 */
1208 #define SQLITE_AFF_MASK     0x67
1209 
1210 /*
1211 ** Additional bit values that can be ORed with an affinity without
1212 ** changing the affinity.
1213 */
1214 #define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
1215 #define SQLITE_STOREP2      0x10  /* Store result in reg[P2] rather than jump */
1216 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
1217 
1218 /*
1219 ** An object of this type is created for each virtual table present in
1220 ** the database schema.
1221 **
1222 ** If the database schema is shared, then there is one instance of this
1223 ** structure for each database connection (sqlite3*) that uses the shared
1224 ** schema. This is because each database connection requires its own unique
1225 ** instance of the sqlite3_vtab* handle used to access the virtual table
1226 ** implementation. sqlite3_vtab* handles can not be shared between
1227 ** database connections, even when the rest of the in-memory database
1228 ** schema is shared, as the implementation often stores the database
1229 ** connection handle passed to it via the xConnect() or xCreate() method
1230 ** during initialization internally. This database connection handle may
1231 ** then be used by the virtual table implementation to access real tables
1232 ** within the database. So that they appear as part of the callers
1233 ** transaction, these accesses need to be made via the same database
1234 ** connection as that used to execute SQL operations on the virtual table.
1235 **
1236 ** All VTable objects that correspond to a single table in a shared
1237 ** database schema are initially stored in a linked-list pointed to by
1238 ** the Table.pVTable member variable of the corresponding Table object.
1239 ** When an sqlite3_prepare() operation is required to access the virtual
1240 ** table, it searches the list for the VTable that corresponds to the
1241 ** database connection doing the preparing so as to use the correct
1242 ** sqlite3_vtab* handle in the compiled query.
1243 **
1244 ** When an in-memory Table object is deleted (for example when the
1245 ** schema is being reloaded for some reason), the VTable objects are not
1246 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
1247 ** immediately. Instead, they are moved from the Table.pVTable list to
1248 ** another linked list headed by the sqlite3.pDisconnect member of the
1249 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
1250 ** next time a statement is prepared using said sqlite3*. This is done
1251 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
1252 ** Refer to comments above function sqlite3VtabUnlockList() for an
1253 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
1254 ** list without holding the corresponding sqlite3.mutex mutex.
1255 **
1256 ** The memory for objects of this type is always allocated by
1257 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
1258 ** the first argument.
1259 */
1260 struct VTable {
1261   sqlite3 *db;              /* Database connection associated with this table */
1262   Module *pMod;             /* Pointer to module implementation */
1263   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
1264   int nRef;                 /* Number of pointers to this structure */
1265   u8 bConstraint;           /* True if constraints are supported */
1266   int iSavepoint;           /* Depth of the SAVEPOINT stack */
1267   VTable *pNext;            /* Next in linked list (see above) */
1268 };
1269 
1270 /*
1271 ** Each SQL table is represented in memory by an instance of the
1272 ** following structure.
1273 **
1274 ** Table.zName is the name of the table.  The case of the original
1275 ** CREATE TABLE statement is stored, but case is not significant for
1276 ** comparisons.
1277 **
1278 ** Table.nCol is the number of columns in this table.  Table.aCol is a
1279 ** pointer to an array of Column structures, one for each column.
1280 **
1281 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
1282 ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
1283 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
1284 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
1285 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
1286 ** is generated for each row of the table.  TF_HasPrimaryKey is set if
1287 ** the table has any PRIMARY KEY, INTEGER or otherwise.
1288 **
1289 ** Table.tnum is the page number for the root BTree page of the table in the
1290 ** database file.  If Table.iDb is the index of the database table backend
1291 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
1292 ** holds temporary tables and indices.  If TF_Ephemeral is set
1293 ** then the table is stored in a file that is automatically deleted
1294 ** when the VDBE cursor to the table is closed.  In this case Table.tnum
1295 ** refers VDBE cursor number that holds the table open, not to the root
1296 ** page number.  Transient tables are used to hold the results of a
1297 ** sub-query that appears instead of a real table name in the FROM clause
1298 ** of a SELECT statement.
1299 */
1300 struct Table {
1301   char *zName;         /* Name of the table or view */
1302   Column *aCol;        /* Information about each column */
1303   Index *pIndex;       /* List of SQL indexes on this table. */
1304   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
1305   FKey *pFKey;         /* Linked list of all foreign keys in this table */
1306   char *zColAff;       /* String defining the affinity of each column */
1307 #ifndef SQLITE_OMIT_CHECK
1308   ExprList *pCheck;    /* All CHECK constraints */
1309 #endif
1310   tRowcnt nRowEst;     /* Estimated rows in table - from sqlite_stat1 table */
1311   int tnum;            /* Root BTree node for this table (see note above) */
1312   i16 iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
1313   i16 nCol;            /* Number of columns in this table */
1314   u16 nRef;            /* Number of pointers to this Table */
1315   u8 tabFlags;         /* Mask of TF_* values */
1316   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
1317 #ifndef SQLITE_OMIT_ALTERTABLE
1318   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
1319 #endif
1320 #ifndef SQLITE_OMIT_VIRTUALTABLE
1321   int nModuleArg;      /* Number of arguments to the module */
1322   char **azModuleArg;  /* Text of all module args. [0] is module name */
1323   VTable *pVTable;     /* List of VTable objects. */
1324 #endif
1325   Trigger *pTrigger;   /* List of triggers stored in pSchema */
1326   Schema *pSchema;     /* Schema that contains this table */
1327   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
1328 };
1329 
1330 /*
1331 ** Allowed values for Tabe.tabFlags.
1332 */
1333 #define TF_Readonly        0x01    /* Read-only system table */
1334 #define TF_Ephemeral       0x02    /* An ephemeral table */
1335 #define TF_HasPrimaryKey   0x04    /* Table has a primary key */
1336 #define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
1337 #define TF_Virtual         0x10    /* Is a virtual table */
1338 
1339 
1340 /*
1341 ** Test to see whether or not a table is a virtual table.  This is
1342 ** done as a macro so that it will be optimized out when virtual
1343 ** table support is omitted from the build.
1344 */
1345 #ifndef SQLITE_OMIT_VIRTUALTABLE
1346 #  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
1347 #  define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
1348 #else
1349 #  define IsVirtual(X)      0
1350 #  define IsHiddenColumn(X) 0
1351 #endif
1352 
1353 /*
1354 ** Each foreign key constraint is an instance of the following structure.
1355 **
1356 ** A foreign key is associated with two tables.  The "from" table is
1357 ** the table that contains the REFERENCES clause that creates the foreign
1358 ** key.  The "to" table is the table that is named in the REFERENCES clause.
1359 ** Consider this example:
1360 **
1361 **     CREATE TABLE ex1(
1362 **       a INTEGER PRIMARY KEY,
1363 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
1364 **     );
1365 **
1366 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
1367 **
1368 ** Each REFERENCES clause generates an instance of the following structure
1369 ** which is attached to the from-table.  The to-table need not exist when
1370 ** the from-table is created.  The existence of the to-table is not checked.
1371 */
1372 struct FKey {
1373   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
1374   FKey *pNextFrom;  /* Next foreign key in pFrom */
1375   char *zTo;        /* Name of table that the key points to (aka: Parent) */
1376   FKey *pNextTo;    /* Next foreign key on table named zTo */
1377   FKey *pPrevTo;    /* Previous foreign key on table named zTo */
1378   int nCol;         /* Number of columns in this key */
1379   /* EV: R-30323-21917 */
1380   u8 isDeferred;    /* True if constraint checking is deferred till COMMIT */
1381   u8 aAction[2];          /* ON DELETE and ON UPDATE actions, respectively */
1382   Trigger *apTrigger[2];  /* Triggers for aAction[] actions */
1383   struct sColMap {  /* Mapping of columns in pFrom to columns in zTo */
1384     int iFrom;         /* Index of column in pFrom */
1385     char *zCol;        /* Name of column in zTo.  If 0 use PRIMARY KEY */
1386   } aCol[1];        /* One entry for each of nCol column s */
1387 };
1388 
1389 /*
1390 ** SQLite supports many different ways to resolve a constraint
1391 ** error.  ROLLBACK processing means that a constraint violation
1392 ** causes the operation in process to fail and for the current transaction
1393 ** to be rolled back.  ABORT processing means the operation in process
1394 ** fails and any prior changes from that one operation are backed out,
1395 ** but the transaction is not rolled back.  FAIL processing means that
1396 ** the operation in progress stops and returns an error code.  But prior
1397 ** changes due to the same operation are not backed out and no rollback
1398 ** occurs.  IGNORE means that the particular row that caused the constraint
1399 ** error is not inserted or updated.  Processing continues and no error
1400 ** is returned.  REPLACE means that preexisting database rows that caused
1401 ** a UNIQUE constraint violation are removed so that the new insert or
1402 ** update can proceed.  Processing continues and no error is reported.
1403 **
1404 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
1405 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
1406 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
1407 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
1408 ** referenced table row is propagated into the row that holds the
1409 ** foreign key.
1410 **
1411 ** The following symbolic values are used to record which type
1412 ** of action to take.
1413 */
1414 #define OE_None     0   /* There is no constraint to check */
1415 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
1416 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
1417 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
1418 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
1419 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
1420 
1421 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
1422 #define OE_SetNull  7   /* Set the foreign key value to NULL */
1423 #define OE_SetDflt  8   /* Set the foreign key value to its default */
1424 #define OE_Cascade  9   /* Cascade the changes */
1425 
1426 #define OE_Default  99  /* Do whatever the default action is */
1427 
1428 
1429 /*
1430 ** An instance of the following structure is passed as the first
1431 ** argument to sqlite3VdbeKeyCompare and is used to control the
1432 ** comparison of the two index keys.
1433 */
1434 struct KeyInfo {
1435   sqlite3 *db;        /* The database connection */
1436   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
1437   u16 nField;         /* Number of entries in aColl[] */
1438   u8 *aSortOrder;     /* Sort order for each column.  May be NULL */
1439   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
1440 };
1441 
1442 /*
1443 ** An instance of the following structure holds information about a
1444 ** single index record that has already been parsed out into individual
1445 ** values.
1446 **
1447 ** A record is an object that contains one or more fields of data.
1448 ** Records are used to store the content of a table row and to store
1449 ** the key of an index.  A blob encoding of a record is created by
1450 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
1451 ** OP_Column opcode.
1452 **
1453 ** This structure holds a record that has already been disassembled
1454 ** into its constituent fields.
1455 */
1456 struct UnpackedRecord {
1457   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
1458   u16 nField;         /* Number of entries in apMem[] */
1459   u8 flags;           /* Boolean settings.  UNPACKED_... below */
1460   i64 rowid;          /* Used by UNPACKED_PREFIX_SEARCH */
1461   Mem *aMem;          /* Values */
1462 };
1463 
1464 /*
1465 ** Allowed values of UnpackedRecord.flags
1466 */
1467 #define UNPACKED_INCRKEY       0x01  /* Make this key an epsilon larger */
1468 #define UNPACKED_PREFIX_MATCH  0x02  /* A prefix match is considered OK */
1469 #define UNPACKED_PREFIX_SEARCH 0x04  /* Ignore final (rowid) field */
1470 
1471 /*
1472 ** Each SQL index is represented in memory by an
1473 ** instance of the following structure.
1474 **
1475 ** The columns of the table that are to be indexed are described
1476 ** by the aiColumn[] field of this structure.  For example, suppose
1477 ** we have the following table and index:
1478 **
1479 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
1480 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
1481 **
1482 ** In the Table structure describing Ex1, nCol==3 because there are
1483 ** three columns in the table.  In the Index structure describing
1484 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
1485 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
1486 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
1487 ** The second column to be indexed (c1) has an index of 0 in
1488 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
1489 **
1490 ** The Index.onError field determines whether or not the indexed columns
1491 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
1492 ** it means this is not a unique index.  Otherwise it is a unique index
1493 ** and the value of Index.onError indicate the which conflict resolution
1494 ** algorithm to employ whenever an attempt is made to insert a non-unique
1495 ** element.
1496 */
1497 struct Index {
1498   char *zName;             /* Name of this index */
1499   int *aiColumn;           /* Which columns are used by this index.  1st is 0 */
1500   tRowcnt *aiRowEst;       /* From ANALYZE: Est. rows selected by each column */
1501   Table *pTable;           /* The SQL table being indexed */
1502   char *zColAff;           /* String defining the affinity of each column */
1503   Index *pNext;            /* The next index associated with the same table */
1504   Schema *pSchema;         /* Schema containing this index */
1505   u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
1506   char **azColl;           /* Array of collation sequence names for index */
1507   int tnum;                /* DB Page containing root of this index */
1508   u16 nColumn;             /* Number of columns in table used by this index */
1509   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
1510   unsigned autoIndex:2;    /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
1511   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
1512 #ifdef SQLITE_ENABLE_STAT3
1513   int nSample;             /* Number of elements in aSample[] */
1514   tRowcnt avgEq;           /* Average nEq value for key values not in aSample */
1515   IndexSample *aSample;    /* Samples of the left-most key */
1516 #endif
1517 };
1518 
1519 /*
1520 ** Each sample stored in the sqlite_stat3 table is represented in memory
1521 ** using a structure of this type.  See documentation at the top of the
1522 ** analyze.c source file for additional information.
1523 */
1524 struct IndexSample {
1525   union {
1526     char *z;        /* Value if eType is SQLITE_TEXT or SQLITE_BLOB */
1527     double r;       /* Value if eType is SQLITE_FLOAT */
1528     i64 i;          /* Value if eType is SQLITE_INTEGER */
1529   } u;
1530   u8 eType;         /* SQLITE_NULL, SQLITE_INTEGER ... etc. */
1531   int nByte;        /* Size in byte of text or blob. */
1532   tRowcnt nEq;      /* Est. number of rows where the key equals this sample */
1533   tRowcnt nLt;      /* Est. number of rows where key is less than this sample */
1534   tRowcnt nDLt;     /* Est. number of distinct keys less than this sample */
1535 };
1536 
1537 /*
1538 ** Each token coming out of the lexer is an instance of
1539 ** this structure.  Tokens are also used as part of an expression.
1540 **
1541 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
1542 ** may contain random values.  Do not make any assumptions about Token.dyn
1543 ** and Token.n when Token.z==0.
1544 */
1545 struct Token {
1546   const char *z;     /* Text of the token.  Not NULL-terminated! */
1547   unsigned int n;    /* Number of characters in this token */
1548 };
1549 
1550 /*
1551 ** An instance of this structure contains information needed to generate
1552 ** code for a SELECT that contains aggregate functions.
1553 **
1554 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
1555 ** pointer to this structure.  The Expr.iColumn field is the index in
1556 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
1557 ** code for that node.
1558 **
1559 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
1560 ** original Select structure that describes the SELECT statement.  These
1561 ** fields do not need to be freed when deallocating the AggInfo structure.
1562 */
1563 struct AggInfo {
1564   u8 directMode;          /* Direct rendering mode means take data directly
1565                           ** from source tables rather than from accumulators */
1566   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
1567                           ** than the source table */
1568   int sortingIdx;         /* Cursor number of the sorting index */
1569   int sortingIdxPTab;     /* Cursor number of pseudo-table */
1570   int nSortingColumn;     /* Number of columns in the sorting index */
1571   ExprList *pGroupBy;     /* The group by clause */
1572   struct AggInfo_col {    /* For each column used in source tables */
1573     Table *pTab;             /* Source table */
1574     int iTable;              /* Cursor number of the source table */
1575     int iColumn;             /* Column number within the source table */
1576     int iSorterColumn;       /* Column number in the sorting index */
1577     int iMem;                /* Memory location that acts as accumulator */
1578     Expr *pExpr;             /* The original expression */
1579   } *aCol;
1580   int nColumn;            /* Number of used entries in aCol[] */
1581   int nAccumulator;       /* Number of columns that show through to the output.
1582                           ** Additional columns are used only as parameters to
1583                           ** aggregate functions */
1584   struct AggInfo_func {   /* For each aggregate function */
1585     Expr *pExpr;             /* Expression encoding the function */
1586     FuncDef *pFunc;          /* The aggregate function implementation */
1587     int iMem;                /* Memory location that acts as accumulator */
1588     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
1589   } *aFunc;
1590   int nFunc;              /* Number of entries in aFunc[] */
1591 };
1592 
1593 /*
1594 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
1595 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
1596 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
1597 ** it uses less memory in the Expr object, which is a big memory user
1598 ** in systems with lots of prepared statements.  And few applications
1599 ** need more than about 10 or 20 variables.  But some extreme users want
1600 ** to have prepared statements with over 32767 variables, and for them
1601 ** the option is available (at compile-time).
1602 */
1603 #if SQLITE_MAX_VARIABLE_NUMBER<=32767
1604 typedef i16 ynVar;
1605 #else
1606 typedef int ynVar;
1607 #endif
1608 
1609 /*
1610 ** Each node of an expression in the parse tree is an instance
1611 ** of this structure.
1612 **
1613 ** Expr.op is the opcode. The integer parser token codes are reused
1614 ** as opcodes here. For example, the parser defines TK_GE to be an integer
1615 ** code representing the ">=" operator. This same integer code is reused
1616 ** to represent the greater-than-or-equal-to operator in the expression
1617 ** tree.
1618 **
1619 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
1620 ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
1621 ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
1622 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
1623 ** then Expr.token contains the name of the function.
1624 **
1625 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
1626 ** binary operator. Either or both may be NULL.
1627 **
1628 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
1629 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
1630 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
1631 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
1632 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
1633 ** valid.
1634 **
1635 ** An expression of the form ID or ID.ID refers to a column in a table.
1636 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
1637 ** the integer cursor number of a VDBE cursor pointing to that table and
1638 ** Expr.iColumn is the column number for the specific column.  If the
1639 ** expression is used as a result in an aggregate SELECT, then the
1640 ** value is also stored in the Expr.iAgg column in the aggregate so that
1641 ** it can be accessed after all aggregates are computed.
1642 **
1643 ** If the expression is an unbound variable marker (a question mark
1644 ** character '?' in the original SQL) then the Expr.iTable holds the index
1645 ** number for that variable.
1646 **
1647 ** If the expression is a subquery then Expr.iColumn holds an integer
1648 ** register number containing the result of the subquery.  If the
1649 ** subquery gives a constant result, then iTable is -1.  If the subquery
1650 ** gives a different answer at different times during statement processing
1651 ** then iTable is the address of a subroutine that computes the subquery.
1652 **
1653 ** If the Expr is of type OP_Column, and the table it is selecting from
1654 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
1655 ** corresponding table definition.
1656 **
1657 ** ALLOCATION NOTES:
1658 **
1659 ** Expr objects can use a lot of memory space in database schema.  To
1660 ** help reduce memory requirements, sometimes an Expr object will be
1661 ** truncated.  And to reduce the number of memory allocations, sometimes
1662 ** two or more Expr objects will be stored in a single memory allocation,
1663 ** together with Expr.zToken strings.
1664 **
1665 ** If the EP_Reduced and EP_TokenOnly flags are set when
1666 ** an Expr object is truncated.  When EP_Reduced is set, then all
1667 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
1668 ** are contained within the same memory allocation.  Note, however, that
1669 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
1670 ** allocated, regardless of whether or not EP_Reduced is set.
1671 */
1672 struct Expr {
1673   u8 op;                 /* Operation performed by this node */
1674   char affinity;         /* The affinity of the column or 0 if not a column */
1675   u16 flags;             /* Various flags.  EP_* See below */
1676   union {
1677     char *zToken;          /* Token value. Zero terminated and dequoted */
1678     int iValue;            /* Non-negative integer value if EP_IntValue */
1679   } u;
1680 
1681   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
1682   ** space is allocated for the fields below this point. An attempt to
1683   ** access them will result in a segfault or malfunction.
1684   *********************************************************************/
1685 
1686   Expr *pLeft;           /* Left subnode */
1687   Expr *pRight;          /* Right subnode */
1688   union {
1689     ExprList *pList;     /* Function arguments or in "<expr> IN (<expr-list)" */
1690     Select *pSelect;     /* Used for sub-selects and "<expr> IN (<select>)" */
1691   } x;
1692 
1693   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
1694   ** space is allocated for the fields below this point. An attempt to
1695   ** access them will result in a segfault or malfunction.
1696   *********************************************************************/
1697 
1698 #if SQLITE_MAX_EXPR_DEPTH>0
1699   int nHeight;           /* Height of the tree headed by this node */
1700 #endif
1701   int iTable;            /* TK_COLUMN: cursor number of table holding column
1702                          ** TK_REGISTER: register number
1703                          ** TK_TRIGGER: 1 -> new, 0 -> old */
1704   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
1705                          ** TK_VARIABLE: variable number (always >= 1). */
1706   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
1707   i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
1708   u8 flags2;             /* Second set of flags.  EP2_... */
1709   u8 op2;                /* TK_REGISTER: original value of Expr.op
1710                          ** TK_COLUMN: the value of p5 for OP_Column
1711                          ** TK_AGG_FUNCTION: nesting depth */
1712   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
1713   Table *pTab;           /* Table for TK_COLUMN expressions. */
1714 };
1715 
1716 /*
1717 ** The following are the meanings of bits in the Expr.flags field.
1718 */
1719 #define EP_FromJoin   0x0001  /* Originated in ON or USING clause of a join */
1720 #define EP_Agg        0x0002  /* Contains one or more aggregate functions */
1721 #define EP_Resolved   0x0004  /* IDs have been resolved to COLUMNs */
1722 #define EP_Error      0x0008  /* Expression contains one or more errors */
1723 #define EP_Distinct   0x0010  /* Aggregate function with DISTINCT keyword */
1724 #define EP_VarSelect  0x0020  /* pSelect is correlated, not constant */
1725 #define EP_DblQuoted  0x0040  /* token.z was originally in "..." */
1726 #define EP_InfixFunc  0x0080  /* True for an infix function: LIKE, GLOB, etc */
1727 #define EP_Collate    0x0100  /* Tree contains a TK_COLLATE opeartor */
1728 #define EP_FixedDest  0x0200  /* Result needed in a specific register */
1729 #define EP_IntValue   0x0400  /* Integer value contained in u.iValue */
1730 #define EP_xIsSelect  0x0800  /* x.pSelect is valid (otherwise x.pList is) */
1731 #define EP_Hint       0x1000  /* Not used */
1732 #define EP_Reduced    0x2000  /* Expr struct is EXPR_REDUCEDSIZE bytes only */
1733 #define EP_TokenOnly  0x4000  /* Expr struct is EXPR_TOKENONLYSIZE bytes only */
1734 #define EP_Static     0x8000  /* Held in memory not obtained from malloc() */
1735 
1736 /*
1737 ** The following are the meanings of bits in the Expr.flags2 field.
1738 */
1739 #define EP2_MallocedToken  0x0001  /* Need to sqlite3DbFree() Expr.zToken */
1740 #define EP2_Irreducible    0x0002  /* Cannot EXPRDUP_REDUCE this Expr */
1741 
1742 /*
1743 ** The pseudo-routine sqlite3ExprSetIrreducible sets the EP2_Irreducible
1744 ** flag on an expression structure.  This flag is used for VV&A only.  The
1745 ** routine is implemented as a macro that only works when in debugging mode,
1746 ** so as not to burden production code.
1747 */
1748 #ifdef SQLITE_DEBUG
1749 # define ExprSetIrreducible(X)  (X)->flags2 |= EP2_Irreducible
1750 #else
1751 # define ExprSetIrreducible(X)
1752 #endif
1753 
1754 /*
1755 ** These macros can be used to test, set, or clear bits in the
1756 ** Expr.flags field.
1757 */
1758 #define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
1759 #define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
1760 #define ExprSetProperty(E,P)     (E)->flags|=(P)
1761 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
1762 
1763 /*
1764 ** Macros to determine the number of bytes required by a normal Expr
1765 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
1766 ** and an Expr struct with the EP_TokenOnly flag set.
1767 */
1768 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
1769 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
1770 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
1771 
1772 /*
1773 ** Flags passed to the sqlite3ExprDup() function. See the header comment
1774 ** above sqlite3ExprDup() for details.
1775 */
1776 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
1777 
1778 /*
1779 ** A list of expressions.  Each expression may optionally have a
1780 ** name.  An expr/name combination can be used in several ways, such
1781 ** as the list of "expr AS ID" fields following a "SELECT" or in the
1782 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
1783 ** also be used as the argument to a function, in which case the a.zName
1784 ** field is not used.
1785 **
1786 ** By default the Expr.zSpan field holds a human-readable description of
1787 ** the expression that is used in the generation of error messages and
1788 ** column labels.  In this case, Expr.zSpan is typically the text of a
1789 ** column expression as it exists in a SELECT statement.  However, if
1790 ** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
1791 ** of the result column in the form: DATABASE.TABLE.COLUMN.  This later
1792 ** form is used for name resolution with nested FROM clauses.
1793 */
1794 struct ExprList {
1795   int nExpr;             /* Number of expressions on the list */
1796   int iECursor;          /* VDBE Cursor associated with this ExprList */
1797   struct ExprList_item { /* For each expression in the list */
1798     Expr *pExpr;            /* The list of expressions */
1799     char *zName;            /* Token associated with this expression */
1800     char *zSpan;            /* Original text of the expression */
1801     u8 sortOrder;           /* 1 for DESC or 0 for ASC */
1802     unsigned done :1;       /* A flag to indicate when processing is finished */
1803     unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
1804     u16 iOrderByCol;        /* For ORDER BY, column number in result set */
1805     u16 iAlias;             /* Index into Parse.aAlias[] for zName */
1806   } *a;                  /* Alloc a power of two greater or equal to nExpr */
1807 };
1808 
1809 /*
1810 ** An instance of this structure is used by the parser to record both
1811 ** the parse tree for an expression and the span of input text for an
1812 ** expression.
1813 */
1814 struct ExprSpan {
1815   Expr *pExpr;          /* The expression parse tree */
1816   const char *zStart;   /* First character of input text */
1817   const char *zEnd;     /* One character past the end of input text */
1818 };
1819 
1820 /*
1821 ** An instance of this structure can hold a simple list of identifiers,
1822 ** such as the list "a,b,c" in the following statements:
1823 **
1824 **      INSERT INTO t(a,b,c) VALUES ...;
1825 **      CREATE INDEX idx ON t(a,b,c);
1826 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
1827 **
1828 ** The IdList.a.idx field is used when the IdList represents the list of
1829 ** column names after a table name in an INSERT statement.  In the statement
1830 **
1831 **     INSERT INTO t(a,b,c) ...
1832 **
1833 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
1834 */
1835 struct IdList {
1836   struct IdList_item {
1837     char *zName;      /* Name of the identifier */
1838     int idx;          /* Index in some Table.aCol[] of a column named zName */
1839   } *a;
1840   int nId;         /* Number of identifiers on the list */
1841 };
1842 
1843 /*
1844 ** The bitmask datatype defined below is used for various optimizations.
1845 **
1846 ** Changing this from a 64-bit to a 32-bit type limits the number of
1847 ** tables in a join to 32 instead of 64.  But it also reduces the size
1848 ** of the library by 738 bytes on ix86.
1849 */
1850 typedef u64 Bitmask;
1851 
1852 /*
1853 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
1854 */
1855 #define BMS  ((int)(sizeof(Bitmask)*8))
1856 
1857 /*
1858 ** The following structure describes the FROM clause of a SELECT statement.
1859 ** Each table or subquery in the FROM clause is a separate element of
1860 ** the SrcList.a[] array.
1861 **
1862 ** With the addition of multiple database support, the following structure
1863 ** can also be used to describe a particular table such as the table that
1864 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
1865 ** such a table must be a simple name: ID.  But in SQLite, the table can
1866 ** now be identified by a database name, a dot, then the table name: ID.ID.
1867 **
1868 ** The jointype starts out showing the join type between the current table
1869 ** and the next table on the list.  The parser builds the list this way.
1870 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
1871 ** jointype expresses the join between the table and the previous table.
1872 **
1873 ** In the colUsed field, the high-order bit (bit 63) is set if the table
1874 ** contains more than 63 columns and the 64-th or later column is used.
1875 */
1876 struct SrcList {
1877   i16 nSrc;        /* Number of tables or subqueries in the FROM clause */
1878   i16 nAlloc;      /* Number of entries allocated in a[] below */
1879   struct SrcList_item {
1880     Schema *pSchema;  /* Schema to which this item is fixed */
1881     char *zDatabase;  /* Name of database holding this table */
1882     char *zName;      /* Name of the table */
1883     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
1884     Table *pTab;      /* An SQL table corresponding to zName */
1885     Select *pSelect;  /* A SELECT statement used in place of a table name */
1886     int addrFillSub;  /* Address of subroutine to manifest a subquery */
1887     int regReturn;    /* Register holding return address of addrFillSub */
1888     u8 jointype;      /* Type of join between this able and the previous */
1889     unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
1890     unsigned isCorrelated :1;  /* True if sub-query is correlated */
1891     unsigned viaCoroutine :1;  /* Implemented as a co-routine */
1892 #ifndef SQLITE_OMIT_EXPLAIN
1893     u8 iSelectId;     /* If pSelect!=0, the id of the sub-select in EQP */
1894 #endif
1895     int iCursor;      /* The VDBE cursor number used to access this table */
1896     Expr *pOn;        /* The ON clause of a join */
1897     IdList *pUsing;   /* The USING clause of a join */
1898     Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
1899     char *zIndex;     /* Identifier from "INDEXED BY <zIndex>" clause */
1900     Index *pIndex;    /* Index structure corresponding to zIndex, if any */
1901   } a[1];             /* One entry for each identifier on the list */
1902 };
1903 
1904 /*
1905 ** Permitted values of the SrcList.a.jointype field
1906 */
1907 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
1908 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
1909 #define JT_NATURAL   0x0004    /* True for a "natural" join */
1910 #define JT_LEFT      0x0008    /* Left outer join */
1911 #define JT_RIGHT     0x0010    /* Right outer join */
1912 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
1913 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
1914 
1915 
1916 /*
1917 ** A WherePlan object holds information that describes a lookup
1918 ** strategy.
1919 **
1920 ** This object is intended to be opaque outside of the where.c module.
1921 ** It is included here only so that that compiler will know how big it
1922 ** is.  None of the fields in this object should be used outside of
1923 ** the where.c module.
1924 **
1925 ** Within the union, pIdx is only used when wsFlags&WHERE_INDEXED is true.
1926 ** pTerm is only used when wsFlags&WHERE_MULTI_OR is true.  And pVtabIdx
1927 ** is only used when wsFlags&WHERE_VIRTUALTABLE is true.  It is never the
1928 ** case that more than one of these conditions is true.
1929 */
1930 struct WherePlan {
1931   u32 wsFlags;                   /* WHERE_* flags that describe the strategy */
1932   u16 nEq;                       /* Number of == constraints */
1933   u16 nOBSat;                    /* Number of ORDER BY terms satisfied */
1934   double nRow;                   /* Estimated number of rows (for EQP) */
1935   union {
1936     Index *pIdx;                   /* Index when WHERE_INDEXED is true */
1937     struct WhereTerm *pTerm;       /* WHERE clause term for OR-search */
1938     sqlite3_index_info *pVtabIdx;  /* Virtual table index to use */
1939   } u;
1940 };
1941 
1942 /*
1943 ** For each nested loop in a WHERE clause implementation, the WhereInfo
1944 ** structure contains a single instance of this structure.  This structure
1945 ** is intended to be private to the where.c module and should not be
1946 ** access or modified by other modules.
1947 **
1948 ** The pIdxInfo field is used to help pick the best index on a
1949 ** virtual table.  The pIdxInfo pointer contains indexing
1950 ** information for the i-th table in the FROM clause before reordering.
1951 ** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
1952 ** All other information in the i-th WhereLevel object for the i-th table
1953 ** after FROM clause ordering.
1954 */
1955 struct WhereLevel {
1956   WherePlan plan;       /* query plan for this element of the FROM clause */
1957   int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
1958   int iTabCur;          /* The VDBE cursor used to access the table */
1959   int iIdxCur;          /* The VDBE cursor used to access pIdx */
1960   int addrBrk;          /* Jump here to break out of the loop */
1961   int addrNxt;          /* Jump here to start the next IN combination */
1962   int addrCont;         /* Jump here to continue with the next loop cycle */
1963   int addrFirst;        /* First instruction of interior of the loop */
1964   u8 iFrom;             /* Which entry in the FROM clause */
1965   u8 op, p5;            /* Opcode and P5 of the opcode that ends the loop */
1966   int p1, p2;           /* Operands of the opcode used to ends the loop */
1967   union {               /* Information that depends on plan.wsFlags */
1968     struct {
1969       int nIn;              /* Number of entries in aInLoop[] */
1970       struct InLoop {
1971         int iCur;              /* The VDBE cursor used by this IN operator */
1972         int addrInTop;         /* Top of the IN loop */
1973         u8 eEndLoopOp;         /* IN Loop terminator. OP_Next or OP_Prev */
1974       } *aInLoop;           /* Information about each nested IN operator */
1975     } in;                 /* Used when plan.wsFlags&WHERE_IN_ABLE */
1976     Index *pCovidx;       /* Possible covering index for WHERE_MULTI_OR */
1977   } u;
1978   double rOptCost;      /* "Optimal" cost for this level */
1979 
1980   /* The following field is really not part of the current level.  But
1981   ** we need a place to cache virtual table index information for each
1982   ** virtual table in the FROM clause and the WhereLevel structure is
1983   ** a convenient place since there is one WhereLevel for each FROM clause
1984   ** element.
1985   */
1986   sqlite3_index_info *pIdxInfo;  /* Index info for n-th source table */
1987 };
1988 
1989 /*
1990 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
1991 ** and the WhereInfo.wctrlFlags member.
1992 */
1993 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
1994 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
1995 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
1996 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
1997 #define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
1998 #define WHERE_OMIT_OPEN_CLOSE  0x0010 /* Table cursors are already open */
1999 #define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
2000 #define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
2001 #define WHERE_AND_ONLY         0x0080 /* Don't use indices for OR terms */
2002 
2003 /*
2004 ** The WHERE clause processing routine has two halves.  The
2005 ** first part does the start of the WHERE loop and the second
2006 ** half does the tail of the WHERE loop.  An instance of
2007 ** this structure is returned by the first half and passed
2008 ** into the second half to give some continuity.
2009 */
2010 struct WhereInfo {
2011   Parse *pParse;            /* Parsing and code generating context */
2012   SrcList *pTabList;        /* List of tables in the join */
2013   u16 nOBSat;               /* Number of ORDER BY terms satisfied by indices */
2014   u16 wctrlFlags;           /* Flags originally passed to sqlite3WhereBegin() */
2015   u8 okOnePass;             /* Ok to use one-pass algorithm for UPDATE/DELETE */
2016   u8 untestedTerms;         /* Not all WHERE terms resolved by outer loop */
2017   u8 eDistinct;             /* One of the WHERE_DISTINCT_* values below */
2018   int iTop;                 /* The very beginning of the WHERE loop */
2019   int iContinue;            /* Jump here to continue with next record */
2020   int iBreak;               /* Jump here to break out of the loop */
2021   int nLevel;               /* Number of nested loop */
2022   struct WhereClause *pWC;  /* Decomposition of the WHERE clause */
2023   double savedNQueryLoop;   /* pParse->nQueryLoop outside the WHERE loop */
2024   double nRowOut;           /* Estimated number of output rows */
2025   WhereLevel a[1];          /* Information about each nest loop in WHERE */
2026 };
2027 
2028 /* Allowed values for WhereInfo.eDistinct and DistinctCtx.eTnctType */
2029 #define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
2030 #define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
2031 #define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
2032 #define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
2033 
2034 /*
2035 ** A NameContext defines a context in which to resolve table and column
2036 ** names.  The context consists of a list of tables (the pSrcList) field and
2037 ** a list of named expression (pEList).  The named expression list may
2038 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
2039 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
2040 ** pEList corresponds to the result set of a SELECT and is NULL for
2041 ** other statements.
2042 **
2043 ** NameContexts can be nested.  When resolving names, the inner-most
2044 ** context is searched first.  If no match is found, the next outer
2045 ** context is checked.  If there is still no match, the next context
2046 ** is checked.  This process continues until either a match is found
2047 ** or all contexts are check.  When a match is found, the nRef member of
2048 ** the context containing the match is incremented.
2049 **
2050 ** Each subquery gets a new NameContext.  The pNext field points to the
2051 ** NameContext in the parent query.  Thus the process of scanning the
2052 ** NameContext list corresponds to searching through successively outer
2053 ** subqueries looking for a match.
2054 */
2055 struct NameContext {
2056   Parse *pParse;       /* The parser */
2057   SrcList *pSrcList;   /* One or more tables used to resolve names */
2058   ExprList *pEList;    /* Optional list of named expressions */
2059   AggInfo *pAggInfo;   /* Information about aggregates at this level */
2060   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
2061   int nRef;            /* Number of names resolved by this context */
2062   int nErr;            /* Number of errors encountered while resolving names */
2063   u8 ncFlags;          /* Zero or more NC_* flags defined below */
2064 };
2065 
2066 /*
2067 ** Allowed values for the NameContext, ncFlags field.
2068 */
2069 #define NC_AllowAgg  0x01    /* Aggregate functions are allowed here */
2070 #define NC_HasAgg    0x02    /* One or more aggregate functions seen */
2071 #define NC_IsCheck   0x04    /* True if resolving names in a CHECK constraint */
2072 #define NC_InAggFunc 0x08    /* True if analyzing arguments to an agg func */
2073 
2074 /*
2075 ** An instance of the following structure contains all information
2076 ** needed to generate code for a single SELECT statement.
2077 **
2078 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
2079 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
2080 ** limit and nOffset to the value of the offset (or 0 if there is not
2081 ** offset).  But later on, nLimit and nOffset become the memory locations
2082 ** in the VDBE that record the limit and offset counters.
2083 **
2084 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
2085 ** These addresses must be stored so that we can go back and fill in
2086 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
2087 ** the number of columns in P2 can be computed at the same time
2088 ** as the OP_OpenEphm instruction is coded because not
2089 ** enough information about the compound query is known at that point.
2090 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
2091 ** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
2092 ** sequences for the ORDER BY clause.
2093 */
2094 struct Select {
2095   ExprList *pEList;      /* The fields of the result */
2096   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
2097   u16 selFlags;          /* Various SF_* values */
2098   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
2099   int addrOpenEphm[3];   /* OP_OpenEphem opcodes related to this select */
2100   double nSelectRow;     /* Estimated number of result rows */
2101   SrcList *pSrc;         /* The FROM clause */
2102   Expr *pWhere;          /* The WHERE clause */
2103   ExprList *pGroupBy;    /* The GROUP BY clause */
2104   Expr *pHaving;         /* The HAVING clause */
2105   ExprList *pOrderBy;    /* The ORDER BY clause */
2106   Select *pPrior;        /* Prior select in a compound select statement */
2107   Select *pNext;         /* Next select to the left in a compound */
2108   Select *pRightmost;    /* Right-most select in a compound select statement */
2109   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
2110   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
2111 };
2112 
2113 /*
2114 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
2115 ** "Select Flag".
2116 */
2117 #define SF_Distinct        0x0001  /* Output should be DISTINCT */
2118 #define SF_Resolved        0x0002  /* Identifiers have been resolved */
2119 #define SF_Aggregate       0x0004  /* Contains aggregate functions */
2120 #define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
2121 #define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
2122 #define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
2123 #define SF_UseSorter       0x0040  /* Sort using a sorter */
2124 #define SF_Values          0x0080  /* Synthesized from VALUES clause */
2125 #define SF_Materialize     0x0100  /* Force materialization of views */
2126 #define SF_NestedFrom      0x0200  /* Part of a parenthesized FROM clause */
2127 
2128 
2129 /*
2130 ** The results of a select can be distributed in several ways.  The
2131 ** "SRT" prefix means "SELECT Result Type".
2132 */
2133 #define SRT_Union        1  /* Store result as keys in an index */
2134 #define SRT_Except       2  /* Remove result from a UNION index */
2135 #define SRT_Exists       3  /* Store 1 if the result is not empty */
2136 #define SRT_Discard      4  /* Do not save the results anywhere */
2137 
2138 /* The ORDER BY clause is ignored for all of the above */
2139 #define IgnorableOrderby(X) ((X->eDest)<=SRT_Discard)
2140 
2141 #define SRT_Output       5  /* Output each row of result */
2142 #define SRT_Mem          6  /* Store result in a memory cell */
2143 #define SRT_Set          7  /* Store results as keys in an index */
2144 #define SRT_Table        8  /* Store result as data with an automatic rowid */
2145 #define SRT_EphemTab     9  /* Create transient tab and store like SRT_Table */
2146 #define SRT_Coroutine   10  /* Generate a single row of result */
2147 
2148 /*
2149 ** An instance of this object describes where to put of the results of
2150 ** a SELECT statement.
2151 */
2152 struct SelectDest {
2153   u8 eDest;         /* How to dispose of the results.  On of SRT_* above. */
2154   char affSdst;     /* Affinity used when eDest==SRT_Set */
2155   int iSDParm;      /* A parameter used by the eDest disposal method */
2156   int iSdst;        /* Base register where results are written */
2157   int nSdst;        /* Number of registers allocated */
2158 };
2159 
2160 /*
2161 ** During code generation of statements that do inserts into AUTOINCREMENT
2162 ** tables, the following information is attached to the Table.u.autoInc.p
2163 ** pointer of each autoincrement table to record some side information that
2164 ** the code generator needs.  We have to keep per-table autoincrement
2165 ** information in case inserts are down within triggers.  Triggers do not
2166 ** normally coordinate their activities, but we do need to coordinate the
2167 ** loading and saving of autoincrement information.
2168 */
2169 struct AutoincInfo {
2170   AutoincInfo *pNext;   /* Next info block in a list of them all */
2171   Table *pTab;          /* Table this info block refers to */
2172   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
2173   int regCtr;           /* Memory register holding the rowid counter */
2174 };
2175 
2176 /*
2177 ** Size of the column cache
2178 */
2179 #ifndef SQLITE_N_COLCACHE
2180 # define SQLITE_N_COLCACHE 10
2181 #endif
2182 
2183 /*
2184 ** At least one instance of the following structure is created for each
2185 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
2186 ** statement. All such objects are stored in the linked list headed at
2187 ** Parse.pTriggerPrg and deleted once statement compilation has been
2188 ** completed.
2189 **
2190 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
2191 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
2192 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
2193 ** The Parse.pTriggerPrg list never contains two entries with the same
2194 ** values for both pTrigger and orconf.
2195 **
2196 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
2197 ** accessed (or set to 0 for triggers fired as a result of INSERT
2198 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
2199 ** a mask of new.* columns used by the program.
2200 */
2201 struct TriggerPrg {
2202   Trigger *pTrigger;      /* Trigger this program was coded from */
2203   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
2204   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
2205   int orconf;             /* Default ON CONFLICT policy */
2206   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
2207 };
2208 
2209 /*
2210 ** The yDbMask datatype for the bitmask of all attached databases.
2211 */
2212 #if SQLITE_MAX_ATTACHED>30
2213   typedef sqlite3_uint64 yDbMask;
2214 #else
2215   typedef unsigned int yDbMask;
2216 #endif
2217 
2218 /*
2219 ** An SQL parser context.  A copy of this structure is passed through
2220 ** the parser and down into all the parser action routine in order to
2221 ** carry around information that is global to the entire parse.
2222 **
2223 ** The structure is divided into two parts.  When the parser and code
2224 ** generate call themselves recursively, the first part of the structure
2225 ** is constant but the second part is reset at the beginning and end of
2226 ** each recursion.
2227 **
2228 ** The nTableLock and aTableLock variables are only used if the shared-cache
2229 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
2230 ** used to store the set of table-locks required by the statement being
2231 ** compiled. Function sqlite3TableLock() is used to add entries to the
2232 ** list.
2233 */
2234 struct Parse {
2235   sqlite3 *db;         /* The main database structure */
2236   char *zErrMsg;       /* An error message */
2237   Vdbe *pVdbe;         /* An engine for executing database bytecode */
2238   int rc;              /* Return code from execution */
2239   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
2240   u8 checkSchema;      /* Causes schema cookie check after an error */
2241   u8 nested;           /* Number of nested calls to the parser/code generator */
2242   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
2243   u8 nTempInUse;       /* Number of aTempReg[] currently checked out */
2244   u8 nColCache;        /* Number of entries in aColCache[] */
2245   u8 iColCache;        /* Next entry in aColCache[] to replace */
2246   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
2247   u8 mayAbort;         /* True if statement may throw an ABORT exception */
2248   int aTempReg[8];     /* Holding area for temporary registers */
2249   int nRangeReg;       /* Size of the temporary register block */
2250   int iRangeReg;       /* First register in temporary register block */
2251   int nErr;            /* Number of errors seen */
2252   int nTab;            /* Number of previously allocated VDBE cursors */
2253   int nMem;            /* Number of memory cells used so far */
2254   int nSet;            /* Number of sets used so far */
2255   int nOnce;           /* Number of OP_Once instructions so far */
2256   int ckBase;          /* Base register of data during check constraints */
2257   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
2258   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
2259   struct yColCache {
2260     int iTable;           /* Table cursor number */
2261     int iColumn;          /* Table column number */
2262     u8 tempReg;           /* iReg is a temp register that needs to be freed */
2263     int iLevel;           /* Nesting level */
2264     int iReg;             /* Reg with value of this column. 0 means none. */
2265     int lru;              /* Least recently used entry has the smallest value */
2266   } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
2267   yDbMask writeMask;   /* Start a write transaction on these databases */
2268   yDbMask cookieMask;  /* Bitmask of schema verified databases */
2269   int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
2270   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
2271   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
2272   int regRoot;         /* Register holding root page number for new objects */
2273   int nMaxArg;         /* Max args passed to user function by sub-program */
2274   Token constraintName;/* Name of the constraint currently being parsed */
2275 #ifndef SQLITE_OMIT_SHARED_CACHE
2276   int nTableLock;        /* Number of locks in aTableLock */
2277   TableLock *aTableLock; /* Required table locks for shared-cache mode */
2278 #endif
2279   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
2280 
2281   /* Information used while coding trigger programs. */
2282   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
2283   Table *pTriggerTab;  /* Table triggers are being coded for */
2284   double nQueryLoop;   /* Estimated number of iterations of a query */
2285   u32 oldmask;         /* Mask of old.* columns referenced */
2286   u32 newmask;         /* Mask of new.* columns referenced */
2287   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
2288   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
2289   u8 disableTriggers;  /* True to disable triggers */
2290 
2291   /* Above is constant between recursions.  Below is reset before and after
2292   ** each recursion */
2293 
2294   int nVar;                 /* Number of '?' variables seen in the SQL so far */
2295   int nzVar;                /* Number of available slots in azVar[] */
2296   u8 explain;               /* True if the EXPLAIN flag is found on the query */
2297 #ifndef SQLITE_OMIT_VIRTUALTABLE
2298   u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
2299   int nVtabLock;            /* Number of virtual tables to lock */
2300 #endif
2301   int nAlias;               /* Number of aliased result set columns */
2302   int nHeight;              /* Expression tree height of current sub-select */
2303 #ifndef SQLITE_OMIT_EXPLAIN
2304   int iSelectId;            /* ID of current select for EXPLAIN output */
2305   int iNextSelectId;        /* Next available select ID for EXPLAIN output */
2306 #endif
2307   char **azVar;             /* Pointers to names of parameters */
2308   Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
2309   int *aAlias;              /* Register used to hold aliased result */
2310   const char *zTail;        /* All SQL text past the last semicolon parsed */
2311   Table *pNewTable;         /* A table being constructed by CREATE TABLE */
2312   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
2313   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
2314   Token sNameToken;         /* Token with unqualified schema object name */
2315   Token sLastToken;         /* The last token parsed */
2316 #ifndef SQLITE_OMIT_VIRTUALTABLE
2317   Token sArg;               /* Complete text of a module argument */
2318   Table **apVtabLock;       /* Pointer to virtual tables needing locking */
2319 #endif
2320   Table *pZombieTab;        /* List of Table objects to delete after code gen */
2321   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
2322 };
2323 
2324 /*
2325 ** Return true if currently inside an sqlite3_declare_vtab() call.
2326 */
2327 #ifdef SQLITE_OMIT_VIRTUALTABLE
2328   #define IN_DECLARE_VTAB 0
2329 #else
2330   #define IN_DECLARE_VTAB (pParse->declareVtab)
2331 #endif
2332 
2333 /*
2334 ** An instance of the following structure can be declared on a stack and used
2335 ** to save the Parse.zAuthContext value so that it can be restored later.
2336 */
2337 struct AuthContext {
2338   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
2339   Parse *pParse;              /* The Parse structure */
2340 };
2341 
2342 /*
2343 ** Bitfield flags for P5 value in various opcodes.
2344 */
2345 #define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
2346 #define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
2347 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
2348 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
2349 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
2350 #define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
2351 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
2352 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
2353 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
2354 #define OPFLAG_P2ISREG       0x02    /* P2 to OP_Open** is a register number */
2355 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
2356 
2357 /*
2358  * Each trigger present in the database schema is stored as an instance of
2359  * struct Trigger.
2360  *
2361  * Pointers to instances of struct Trigger are stored in two ways.
2362  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
2363  *    database). This allows Trigger structures to be retrieved by name.
2364  * 2. All triggers associated with a single table form a linked list, using the
2365  *    pNext member of struct Trigger. A pointer to the first element of the
2366  *    linked list is stored as the "pTrigger" member of the associated
2367  *    struct Table.
2368  *
2369  * The "step_list" member points to the first element of a linked list
2370  * containing the SQL statements specified as the trigger program.
2371  */
2372 struct Trigger {
2373   char *zName;            /* The name of the trigger                        */
2374   char *table;            /* The table or view to which the trigger applies */
2375   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
2376   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
2377   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
2378   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
2379                              the <column-list> is stored here */
2380   Schema *pSchema;        /* Schema containing the trigger */
2381   Schema *pTabSchema;     /* Schema containing the table */
2382   TriggerStep *step_list; /* Link list of trigger program steps             */
2383   Trigger *pNext;         /* Next trigger associated with the table */
2384 };
2385 
2386 /*
2387 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
2388 ** determine which.
2389 **
2390 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
2391 ** In that cases, the constants below can be ORed together.
2392 */
2393 #define TRIGGER_BEFORE  1
2394 #define TRIGGER_AFTER   2
2395 
2396 /*
2397  * An instance of struct TriggerStep is used to store a single SQL statement
2398  * that is a part of a trigger-program.
2399  *
2400  * Instances of struct TriggerStep are stored in a singly linked list (linked
2401  * using the "pNext" member) referenced by the "step_list" member of the
2402  * associated struct Trigger instance. The first element of the linked list is
2403  * the first step of the trigger-program.
2404  *
2405  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
2406  * "SELECT" statement. The meanings of the other members is determined by the
2407  * value of "op" as follows:
2408  *
2409  * (op == TK_INSERT)
2410  * orconf    -> stores the ON CONFLICT algorithm
2411  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
2412  *              this stores a pointer to the SELECT statement. Otherwise NULL.
2413  * target    -> A token holding the quoted name of the table to insert into.
2414  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
2415  *              this stores values to be inserted. Otherwise NULL.
2416  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
2417  *              statement, then this stores the column-names to be
2418  *              inserted into.
2419  *
2420  * (op == TK_DELETE)
2421  * target    -> A token holding the quoted name of the table to delete from.
2422  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
2423  *              Otherwise NULL.
2424  *
2425  * (op == TK_UPDATE)
2426  * target    -> A token holding the quoted name of the table to update rows of.
2427  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
2428  *              Otherwise NULL.
2429  * pExprList -> A list of the columns to update and the expressions to update
2430  *              them to. See sqlite3Update() documentation of "pChanges"
2431  *              argument.
2432  *
2433  */
2434 struct TriggerStep {
2435   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
2436   u8 orconf;           /* OE_Rollback etc. */
2437   Trigger *pTrig;      /* The trigger that this step is a part of */
2438   Select *pSelect;     /* SELECT statment or RHS of INSERT INTO .. SELECT ... */
2439   Token target;        /* Target table for DELETE, UPDATE, INSERT */
2440   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
2441   ExprList *pExprList; /* SET clause for UPDATE.  VALUES clause for INSERT */
2442   IdList *pIdList;     /* Column names for INSERT */
2443   TriggerStep *pNext;  /* Next in the link-list */
2444   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
2445 };
2446 
2447 /*
2448 ** The following structure contains information used by the sqliteFix...
2449 ** routines as they walk the parse tree to make database references
2450 ** explicit.
2451 */
2452 typedef struct DbFixer DbFixer;
2453 struct DbFixer {
2454   Parse *pParse;      /* The parsing context.  Error messages written here */
2455   Schema *pSchema;    /* Fix items to this schema */
2456   const char *zDb;    /* Make sure all objects are contained in this database */
2457   const char *zType;  /* Type of the container - used for error messages */
2458   const Token *pName; /* Name of the container - used for error messages */
2459 };
2460 
2461 /*
2462 ** An objected used to accumulate the text of a string where we
2463 ** do not necessarily know how big the string will be in the end.
2464 */
2465 struct StrAccum {
2466   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
2467   char *zBase;         /* A base allocation.  Not from malloc. */
2468   char *zText;         /* The string collected so far */
2469   int  nChar;          /* Length of the string so far */
2470   int  nAlloc;         /* Amount of space allocated in zText */
2471   int  mxAlloc;        /* Maximum allowed string length */
2472   u8   mallocFailed;   /* Becomes true if any memory allocation fails */
2473   u8   useMalloc;      /* 0: none,  1: sqlite3DbMalloc,  2: sqlite3_malloc */
2474   u8   tooBig;         /* Becomes true if string size exceeds limits */
2475 };
2476 
2477 /*
2478 ** A pointer to this structure is used to communicate information
2479 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
2480 */
2481 typedef struct {
2482   sqlite3 *db;        /* The database being initialized */
2483   char **pzErrMsg;    /* Error message stored here */
2484   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
2485   int rc;             /* Result code stored here */
2486 } InitData;
2487 
2488 /*
2489 ** Structure containing global configuration data for the SQLite library.
2490 **
2491 ** This structure also contains some state information.
2492 */
2493 struct Sqlite3Config {
2494   int bMemstat;                     /* True to enable memory status */
2495   int bCoreMutex;                   /* True to enable core mutexing */
2496   int bFullMutex;                   /* True to enable full mutexing */
2497   int bOpenUri;                     /* True to interpret filenames as URIs */
2498   int bUseCis;                      /* Use covering indices for full-scans */
2499   int mxStrlen;                     /* Maximum string length */
2500   int szLookaside;                  /* Default lookaside buffer size */
2501   int nLookaside;                   /* Default lookaside buffer count */
2502   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
2503   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
2504   sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
2505   void *pHeap;                      /* Heap storage space */
2506   int nHeap;                        /* Size of pHeap[] */
2507   int mnReq, mxReq;                 /* Min and max heap requests sizes */
2508   void *pScratch;                   /* Scratch memory */
2509   int szScratch;                    /* Size of each scratch buffer */
2510   int nScratch;                     /* Number of scratch buffers */
2511   void *pPage;                      /* Page cache memory */
2512   int szPage;                       /* Size of each page in pPage[] */
2513   int nPage;                        /* Number of pages in pPage[] */
2514   int mxParserStack;                /* maximum depth of the parser stack */
2515   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
2516   /* The above might be initialized to non-zero.  The following need to always
2517   ** initially be zero, however. */
2518   int isInit;                       /* True after initialization has finished */
2519   int inProgress;                   /* True while initialization in progress */
2520   int isMutexInit;                  /* True after mutexes are initialized */
2521   int isMallocInit;                 /* True after malloc is initialized */
2522   int isPCacheInit;                 /* True after malloc is initialized */
2523   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
2524   int nRefInitMutex;                /* Number of users of pInitMutex */
2525   void (*xLog)(void*,int,const char*); /* Function for logging */
2526   void *pLogArg;                       /* First argument to xLog() */
2527   int bLocaltimeFault;              /* True to fail localtime() calls */
2528 #ifdef SQLITE_ENABLE_SQLLOG
2529   void(*xSqllog)(void*,sqlite3*,const char*, int);
2530   void *pSqllogArg;
2531 #endif
2532 };
2533 
2534 /*
2535 ** Context pointer passed down through the tree-walk.
2536 */
2537 struct Walker {
2538   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
2539   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
2540   Parse *pParse;                            /* Parser context.  */
2541   int walkerDepth;                          /* Number of subqueries */
2542   union {                                   /* Extra data for callback */
2543     NameContext *pNC;                          /* Naming context */
2544     int i;                                     /* Integer value */
2545     SrcList *pSrcList;                         /* FROM clause */
2546     struct SrcCount *pSrcCount;                /* Counting column references */
2547   } u;
2548 };
2549 
2550 /* Forward declarations */
2551 int sqlite3WalkExpr(Walker*, Expr*);
2552 int sqlite3WalkExprList(Walker*, ExprList*);
2553 int sqlite3WalkSelect(Walker*, Select*);
2554 int sqlite3WalkSelectExpr(Walker*, Select*);
2555 int sqlite3WalkSelectFrom(Walker*, Select*);
2556 
2557 /*
2558 ** Return code from the parse-tree walking primitives and their
2559 ** callbacks.
2560 */
2561 #define WRC_Continue    0   /* Continue down into children */
2562 #define WRC_Prune       1   /* Omit children but continue walking siblings */
2563 #define WRC_Abort       2   /* Abandon the tree walk */
2564 
2565 /*
2566 ** Assuming zIn points to the first byte of a UTF-8 character,
2567 ** advance zIn to point to the first byte of the next UTF-8 character.
2568 */
2569 #define SQLITE_SKIP_UTF8(zIn) {                        \
2570   if( (*(zIn++))>=0xc0 ){                              \
2571     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
2572   }                                                    \
2573 }
2574 
2575 /*
2576 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
2577 ** the same name but without the _BKPT suffix.  These macros invoke
2578 ** routines that report the line-number on which the error originated
2579 ** using sqlite3_log().  The routines also provide a convenient place
2580 ** to set a debugger breakpoint.
2581 */
2582 int sqlite3CorruptError(int);
2583 int sqlite3MisuseError(int);
2584 int sqlite3CantopenError(int);
2585 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
2586 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
2587 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
2588 
2589 
2590 /*
2591 ** FTS4 is really an extension for FTS3.  It is enabled using the
2592 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also all
2593 ** the SQLITE_ENABLE_FTS4 macro to serve as an alisse for SQLITE_ENABLE_FTS3.
2594 */
2595 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
2596 # define SQLITE_ENABLE_FTS3
2597 #endif
2598 
2599 /*
2600 ** The ctype.h header is needed for non-ASCII systems.  It is also
2601 ** needed by FTS3 when FTS3 is included in the amalgamation.
2602 */
2603 #if !defined(SQLITE_ASCII) || \
2604     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
2605 # include <ctype.h>
2606 #endif
2607 
2608 /*
2609 ** The following macros mimic the standard library functions toupper(),
2610 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
2611 ** sqlite versions only work for ASCII characters, regardless of locale.
2612 */
2613 #ifdef SQLITE_ASCII
2614 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
2615 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
2616 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
2617 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
2618 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
2619 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
2620 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
2621 #else
2622 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
2623 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
2624 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
2625 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
2626 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
2627 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
2628 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
2629 #endif
2630 
2631 /*
2632 ** Internal function prototypes
2633 */
2634 #define sqlite3StrICmp sqlite3_stricmp
2635 int sqlite3Strlen30(const char*);
2636 #define sqlite3StrNICmp sqlite3_strnicmp
2637 
2638 int sqlite3MallocInit(void);
2639 void sqlite3MallocEnd(void);
2640 void *sqlite3Malloc(int);
2641 void *sqlite3MallocZero(int);
2642 void *sqlite3DbMallocZero(sqlite3*, int);
2643 void *sqlite3DbMallocRaw(sqlite3*, int);
2644 char *sqlite3DbStrDup(sqlite3*,const char*);
2645 char *sqlite3DbStrNDup(sqlite3*,const char*, int);
2646 void *sqlite3Realloc(void*, int);
2647 void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
2648 void *sqlite3DbRealloc(sqlite3 *, void *, int);
2649 void sqlite3DbFree(sqlite3*, void*);
2650 int sqlite3MallocSize(void*);
2651 int sqlite3DbMallocSize(sqlite3*, void*);
2652 void *sqlite3ScratchMalloc(int);
2653 void sqlite3ScratchFree(void*);
2654 void *sqlite3PageMalloc(int);
2655 void sqlite3PageFree(void*);
2656 void sqlite3MemSetDefault(void);
2657 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
2658 int sqlite3HeapNearlyFull(void);
2659 
2660 /*
2661 ** On systems with ample stack space and that support alloca(), make
2662 ** use of alloca() to obtain space for large automatic objects.  By default,
2663 ** obtain space from malloc().
2664 **
2665 ** The alloca() routine never returns NULL.  This will cause code paths
2666 ** that deal with sqlite3StackAlloc() failures to be unreachable.
2667 */
2668 #ifdef SQLITE_USE_ALLOCA
2669 # define sqlite3StackAllocRaw(D,N)   alloca(N)
2670 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
2671 # define sqlite3StackFree(D,P)
2672 #else
2673 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
2674 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
2675 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
2676 #endif
2677 
2678 #ifdef SQLITE_ENABLE_MEMSYS3
2679 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
2680 #endif
2681 #ifdef SQLITE_ENABLE_MEMSYS5
2682 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
2683 #endif
2684 
2685 
2686 #ifndef SQLITE_MUTEX_OMIT
2687   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
2688   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
2689   sqlite3_mutex *sqlite3MutexAlloc(int);
2690   int sqlite3MutexInit(void);
2691   int sqlite3MutexEnd(void);
2692 #endif
2693 
2694 int sqlite3StatusValue(int);
2695 void sqlite3StatusAdd(int, int);
2696 void sqlite3StatusSet(int, int);
2697 
2698 #ifndef SQLITE_OMIT_FLOATING_POINT
2699   int sqlite3IsNaN(double);
2700 #else
2701 # define sqlite3IsNaN(X)  0
2702 #endif
2703 
2704 void sqlite3VXPrintf(StrAccum*, int, const char*, va_list);
2705 #ifndef SQLITE_OMIT_TRACE
2706 void sqlite3XPrintf(StrAccum*, const char*, ...);
2707 #endif
2708 char *sqlite3MPrintf(sqlite3*,const char*, ...);
2709 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
2710 char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
2711 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
2712   void sqlite3DebugPrintf(const char*, ...);
2713 #endif
2714 #if defined(SQLITE_TEST)
2715   void *sqlite3TestTextToPtr(const char*);
2716 #endif
2717 
2718 /* Output formatting for SQLITE_TESTCTRL_EXPLAIN */
2719 #if defined(SQLITE_ENABLE_TREE_EXPLAIN)
2720   void sqlite3ExplainBegin(Vdbe*);
2721   void sqlite3ExplainPrintf(Vdbe*, const char*, ...);
2722   void sqlite3ExplainNL(Vdbe*);
2723   void sqlite3ExplainPush(Vdbe*);
2724   void sqlite3ExplainPop(Vdbe*);
2725   void sqlite3ExplainFinish(Vdbe*);
2726   void sqlite3ExplainSelect(Vdbe*, Select*);
2727   void sqlite3ExplainExpr(Vdbe*, Expr*);
2728   void sqlite3ExplainExprList(Vdbe*, ExprList*);
2729   const char *sqlite3VdbeExplanation(Vdbe*);
2730 #else
2731 # define sqlite3ExplainBegin(X)
2732 # define sqlite3ExplainSelect(A,B)
2733 # define sqlite3ExplainExpr(A,B)
2734 # define sqlite3ExplainExprList(A,B)
2735 # define sqlite3ExplainFinish(X)
2736 # define sqlite3VdbeExplanation(X) 0
2737 #endif
2738 
2739 
2740 void sqlite3SetString(char **, sqlite3*, const char*, ...);
2741 void sqlite3ErrorMsg(Parse*, const char*, ...);
2742 int sqlite3Dequote(char*);
2743 int sqlite3KeywordCode(const unsigned char*, int);
2744 int sqlite3RunParser(Parse*, const char*, char **);
2745 void sqlite3FinishCoding(Parse*);
2746 int sqlite3GetTempReg(Parse*);
2747 void sqlite3ReleaseTempReg(Parse*,int);
2748 int sqlite3GetTempRange(Parse*,int);
2749 void sqlite3ReleaseTempRange(Parse*,int,int);
2750 void sqlite3ClearTempRegCache(Parse*);
2751 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
2752 Expr *sqlite3Expr(sqlite3*,int,const char*);
2753 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
2754 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
2755 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
2756 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
2757 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
2758 void sqlite3ExprDelete(sqlite3*, Expr*);
2759 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
2760 void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
2761 void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
2762 void sqlite3ExprListDelete(sqlite3*, ExprList*);
2763 int sqlite3Init(sqlite3*, char**);
2764 int sqlite3InitCallback(void*, int, char**, char**);
2765 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
2766 void sqlite3ResetAllSchemasOfConnection(sqlite3*);
2767 void sqlite3ResetOneSchema(sqlite3*,int);
2768 void sqlite3CollapseDatabaseArray(sqlite3*);
2769 void sqlite3BeginParse(Parse*,int);
2770 void sqlite3CommitInternalChanges(sqlite3*);
2771 Table *sqlite3ResultSetOfSelect(Parse*,Select*);
2772 void sqlite3OpenMasterTable(Parse *, int);
2773 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
2774 void sqlite3AddColumn(Parse*,Token*);
2775 void sqlite3AddNotNull(Parse*, int);
2776 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
2777 void sqlite3AddCheckConstraint(Parse*, Expr*);
2778 void sqlite3AddColumnType(Parse*,Token*);
2779 void sqlite3AddDefaultValue(Parse*,ExprSpan*);
2780 void sqlite3AddCollateType(Parse*, Token*);
2781 void sqlite3EndTable(Parse*,Token*,Token*,Select*);
2782 int sqlite3ParseUri(const char*,const char*,unsigned int*,
2783                     sqlite3_vfs**,char**,char **);
2784 Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
2785 int sqlite3CodeOnce(Parse *);
2786 
2787 Bitvec *sqlite3BitvecCreate(u32);
2788 int sqlite3BitvecTest(Bitvec*, u32);
2789 int sqlite3BitvecSet(Bitvec*, u32);
2790 void sqlite3BitvecClear(Bitvec*, u32, void*);
2791 void sqlite3BitvecDestroy(Bitvec*);
2792 u32 sqlite3BitvecSize(Bitvec*);
2793 int sqlite3BitvecBuiltinTest(int,int*);
2794 
2795 RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
2796 void sqlite3RowSetClear(RowSet*);
2797 void sqlite3RowSetInsert(RowSet*, i64);
2798 int sqlite3RowSetTest(RowSet*, u8 iBatch, i64);
2799 int sqlite3RowSetNext(RowSet*, i64*);
2800 
2801 void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
2802 
2803 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
2804   int sqlite3ViewGetColumnNames(Parse*,Table*);
2805 #else
2806 # define sqlite3ViewGetColumnNames(A,B) 0
2807 #endif
2808 
2809 void sqlite3DropTable(Parse*, SrcList*, int, int);
2810 void sqlite3CodeDropTable(Parse*, Table*, int, int);
2811 void sqlite3DeleteTable(sqlite3*, Table*);
2812 #ifndef SQLITE_OMIT_AUTOINCREMENT
2813   void sqlite3AutoincrementBegin(Parse *pParse);
2814   void sqlite3AutoincrementEnd(Parse *pParse);
2815 #else
2816 # define sqlite3AutoincrementBegin(X)
2817 # define sqlite3AutoincrementEnd(X)
2818 #endif
2819 int sqlite3CodeCoroutine(Parse*, Select*, SelectDest*);
2820 void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
2821 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
2822 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
2823 int sqlite3IdListIndex(IdList*,const char*);
2824 SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
2825 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
2826 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
2827                                       Token*, Select*, Expr*, IdList*);
2828 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
2829 int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
2830 void sqlite3SrcListShiftJoinType(SrcList*);
2831 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
2832 void sqlite3IdListDelete(sqlite3*, IdList*);
2833 void sqlite3SrcListDelete(sqlite3*, SrcList*);
2834 Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
2835                         Token*, int, int);
2836 void sqlite3DropIndex(Parse*, SrcList*, int);
2837 int sqlite3Select(Parse*, Select*, SelectDest*);
2838 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
2839                          Expr*,ExprList*,u16,Expr*,Expr*);
2840 void sqlite3SelectDelete(sqlite3*, Select*);
2841 Table *sqlite3SrcListLookup(Parse*, SrcList*);
2842 int sqlite3IsReadOnly(Parse*, Table*, int);
2843 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
2844 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
2845 Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,Expr*,char*);
2846 #endif
2847 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
2848 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
2849 WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
2850 void sqlite3WhereEnd(WhereInfo*);
2851 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
2852 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
2853 void sqlite3ExprCodeMove(Parse*, int, int, int);
2854 void sqlite3ExprCacheStore(Parse*, int, int, int);
2855 void sqlite3ExprCachePush(Parse*);
2856 void sqlite3ExprCachePop(Parse*, int);
2857 void sqlite3ExprCacheRemove(Parse*, int, int);
2858 void sqlite3ExprCacheClear(Parse*);
2859 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
2860 int sqlite3ExprCode(Parse*, Expr*, int);
2861 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
2862 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
2863 int sqlite3ExprCodeAndCache(Parse*, Expr*, int);
2864 void sqlite3ExprCodeConstants(Parse*, Expr*);
2865 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int);
2866 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
2867 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
2868 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
2869 Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
2870 Table *sqlite3LocateTableItem(Parse*,int isView,struct SrcList_item *);
2871 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
2872 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
2873 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
2874 void sqlite3Vacuum(Parse*);
2875 int sqlite3RunVacuum(char**, sqlite3*);
2876 char *sqlite3NameFromToken(sqlite3*, Token*);
2877 int sqlite3ExprCompare(Expr*, Expr*);
2878 int sqlite3ExprListCompare(ExprList*, ExprList*);
2879 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
2880 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
2881 int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
2882 Vdbe *sqlite3GetVdbe(Parse*);
2883 void sqlite3PrngSaveState(void);
2884 void sqlite3PrngRestoreState(void);
2885 void sqlite3PrngResetState(void);
2886 void sqlite3RollbackAll(sqlite3*,int);
2887 void sqlite3CodeVerifySchema(Parse*, int);
2888 void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
2889 void sqlite3BeginTransaction(Parse*, int);
2890 void sqlite3CommitTransaction(Parse*);
2891 void sqlite3RollbackTransaction(Parse*);
2892 void sqlite3Savepoint(Parse*, int, Token*);
2893 void sqlite3CloseSavepoints(sqlite3 *);
2894 void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
2895 int sqlite3ExprIsConstant(Expr*);
2896 int sqlite3ExprIsConstantNotJoin(Expr*);
2897 int sqlite3ExprIsConstantOrFunction(Expr*);
2898 int sqlite3ExprIsInteger(Expr*, int*);
2899 int sqlite3ExprCanBeNull(const Expr*);
2900 void sqlite3ExprCodeIsNullJump(Vdbe*, const Expr*, int, int);
2901 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
2902 int sqlite3IsRowid(const char*);
2903 void sqlite3GenerateRowDelete(Parse*, Table*, int, int, int, Trigger *, int);
2904 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int*);
2905 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int);
2906 void sqlite3GenerateConstraintChecks(Parse*,Table*,int,int,
2907                                      int*,int,int,int,int,int*);
2908 void sqlite3CompleteInsertion(Parse*, Table*, int, int, int*, int, int, int);
2909 int sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
2910 void sqlite3BeginWriteOperation(Parse*, int, int);
2911 void sqlite3MultiWrite(Parse*);
2912 void sqlite3MayAbort(Parse*);
2913 void sqlite3HaltConstraint(Parse*, int, int, char*, int);
2914 Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
2915 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
2916 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
2917 IdList *sqlite3IdListDup(sqlite3*,IdList*);
2918 Select *sqlite3SelectDup(sqlite3*,Select*,int);
2919 void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
2920 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
2921 void sqlite3RegisterBuiltinFunctions(sqlite3*);
2922 void sqlite3RegisterDateTimeFunctions(void);
2923 void sqlite3RegisterGlobalFunctions(void);
2924 int sqlite3SafetyCheckOk(sqlite3*);
2925 int sqlite3SafetyCheckSickOrOk(sqlite3*);
2926 void sqlite3ChangeCookie(Parse*, int);
2927 
2928 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
2929 void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
2930 #endif
2931 
2932 #ifndef SQLITE_OMIT_TRIGGER
2933   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
2934                            Expr*,int, int);
2935   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
2936   void sqlite3DropTrigger(Parse*, SrcList*, int);
2937   void sqlite3DropTriggerPtr(Parse*, Trigger*);
2938   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
2939   Trigger *sqlite3TriggerList(Parse *, Table *);
2940   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
2941                             int, int, int);
2942   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
2943   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
2944   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
2945   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
2946   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
2947                                         ExprList*,Select*,u8);
2948   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
2949   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
2950   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
2951   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
2952   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
2953 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
2954 #else
2955 # define sqlite3TriggersExist(B,C,D,E,F) 0
2956 # define sqlite3DeleteTrigger(A,B)
2957 # define sqlite3DropTriggerPtr(A,B)
2958 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
2959 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
2960 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
2961 # define sqlite3TriggerList(X, Y) 0
2962 # define sqlite3ParseToplevel(p) p
2963 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
2964 #endif
2965 
2966 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
2967 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
2968 void sqlite3DeferForeignKey(Parse*, int);
2969 #ifndef SQLITE_OMIT_AUTHORIZATION
2970   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
2971   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
2972   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
2973   void sqlite3AuthContextPop(AuthContext*);
2974   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
2975 #else
2976 # define sqlite3AuthRead(a,b,c,d)
2977 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
2978 # define sqlite3AuthContextPush(a,b,c)
2979 # define sqlite3AuthContextPop(a)  ((void)(a))
2980 #endif
2981 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
2982 void sqlite3Detach(Parse*, Expr*);
2983 int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
2984 int sqlite3FixSrcList(DbFixer*, SrcList*);
2985 int sqlite3FixSelect(DbFixer*, Select*);
2986 int sqlite3FixExpr(DbFixer*, Expr*);
2987 int sqlite3FixExprList(DbFixer*, ExprList*);
2988 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
2989 int sqlite3AtoF(const char *z, double*, int, u8);
2990 int sqlite3GetInt32(const char *, int*);
2991 int sqlite3Atoi(const char*);
2992 int sqlite3Utf16ByteLen(const void *pData, int nChar);
2993 int sqlite3Utf8CharLen(const char *pData, int nByte);
2994 u32 sqlite3Utf8Read(const u8**);
2995 
2996 /*
2997 ** Routines to read and write variable-length integers.  These used to
2998 ** be defined locally, but now we use the varint routines in the util.c
2999 ** file.  Code should use the MACRO forms below, as the Varint32 versions
3000 ** are coded to assume the single byte case is already handled (which
3001 ** the MACRO form does).
3002 */
3003 int sqlite3PutVarint(unsigned char*, u64);
3004 int sqlite3PutVarint32(unsigned char*, u32);
3005 u8 sqlite3GetVarint(const unsigned char *, u64 *);
3006 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
3007 int sqlite3VarintLen(u64 v);
3008 
3009 /*
3010 ** The header of a record consists of a sequence variable-length integers.
3011 ** These integers are almost always small and are encoded as a single byte.
3012 ** The following macros take advantage this fact to provide a fast encode
3013 ** and decode of the integers in a record header.  It is faster for the common
3014 ** case where the integer is a single byte.  It is a little slower when the
3015 ** integer is two or more bytes.  But overall it is faster.
3016 **
3017 ** The following expressions are equivalent:
3018 **
3019 **     x = sqlite3GetVarint32( A, &B );
3020 **     x = sqlite3PutVarint32( A, B );
3021 **
3022 **     x = getVarint32( A, B );
3023 **     x = putVarint32( A, B );
3024 **
3025 */
3026 #define getVarint32(A,B)  \
3027   (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
3028 #define putVarint32(A,B)  \
3029   (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
3030   sqlite3PutVarint32((A),(B)))
3031 #define getVarint    sqlite3GetVarint
3032 #define putVarint    sqlite3PutVarint
3033 
3034 
3035 const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
3036 void sqlite3TableAffinityStr(Vdbe *, Table *);
3037 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
3038 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
3039 char sqlite3ExprAffinity(Expr *pExpr);
3040 int sqlite3Atoi64(const char*, i64*, int, u8);
3041 void sqlite3Error(sqlite3*, int, const char*,...);
3042 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
3043 u8 sqlite3HexToInt(int h);
3044 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
3045 const char *sqlite3ErrStr(int);
3046 int sqlite3ReadSchema(Parse *pParse);
3047 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
3048 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
3049 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
3050 Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, Token*);
3051 Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
3052 Expr *sqlite3ExprSkipCollate(Expr*);
3053 int sqlite3CheckCollSeq(Parse *, CollSeq *);
3054 int sqlite3CheckObjectName(Parse *, const char *);
3055 void sqlite3VdbeSetChanges(sqlite3 *, int);
3056 int sqlite3AddInt64(i64*,i64);
3057 int sqlite3SubInt64(i64*,i64);
3058 int sqlite3MulInt64(i64*,i64);
3059 int sqlite3AbsInt32(int);
3060 #ifdef SQLITE_ENABLE_8_3_NAMES
3061 void sqlite3FileSuffix3(const char*, char*);
3062 #else
3063 # define sqlite3FileSuffix3(X,Y)
3064 #endif
3065 u8 sqlite3GetBoolean(const char *z,int);
3066 
3067 const void *sqlite3ValueText(sqlite3_value*, u8);
3068 int sqlite3ValueBytes(sqlite3_value*, u8);
3069 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
3070                         void(*)(void*));
3071 void sqlite3ValueFree(sqlite3_value*);
3072 sqlite3_value *sqlite3ValueNew(sqlite3 *);
3073 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
3074 #ifdef SQLITE_ENABLE_STAT3
3075 char *sqlite3Utf8to16(sqlite3 *, u8, char *, int, int *);
3076 #endif
3077 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
3078 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
3079 #ifndef SQLITE_AMALGAMATION
3080 extern const unsigned char sqlite3OpcodeProperty[];
3081 extern const unsigned char sqlite3UpperToLower[];
3082 extern const unsigned char sqlite3CtypeMap[];
3083 extern const Token sqlite3IntTokens[];
3084 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
3085 extern SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
3086 #ifndef SQLITE_OMIT_WSD
3087 extern int sqlite3PendingByte;
3088 #endif
3089 #endif
3090 void sqlite3RootPageMoved(sqlite3*, int, int, int);
3091 void sqlite3Reindex(Parse*, Token*, Token*);
3092 void sqlite3AlterFunctions(void);
3093 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
3094 int sqlite3GetToken(const unsigned char *, int *);
3095 void sqlite3NestedParse(Parse*, const char*, ...);
3096 void sqlite3ExpirePreparedStatements(sqlite3*);
3097 int sqlite3CodeSubselect(Parse *, Expr *, int, int);
3098 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
3099 int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
3100 int sqlite3ResolveExprNames(NameContext*, Expr*);
3101 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
3102 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
3103 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
3104 void sqlite3AlterFinishAddColumn(Parse *, Token *);
3105 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
3106 CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
3107 char sqlite3AffinityType(const char*);
3108 void sqlite3Analyze(Parse*, Token*, Token*);
3109 int sqlite3InvokeBusyHandler(BusyHandler*);
3110 int sqlite3FindDb(sqlite3*, Token*);
3111 int sqlite3FindDbName(sqlite3 *, const char *);
3112 int sqlite3AnalysisLoad(sqlite3*,int iDB);
3113 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
3114 void sqlite3DefaultRowEst(Index*);
3115 void sqlite3RegisterLikeFunctions(sqlite3*, int);
3116 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
3117 void sqlite3MinimumFileFormat(Parse*, int, int);
3118 void sqlite3SchemaClear(void *);
3119 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
3120 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
3121 KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
3122 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
3123   void (*)(sqlite3_context*,int,sqlite3_value **),
3124   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
3125   FuncDestructor *pDestructor
3126 );
3127 int sqlite3ApiExit(sqlite3 *db, int);
3128 int sqlite3OpenTempDatabase(Parse *);
3129 
3130 void sqlite3StrAccumInit(StrAccum*, char*, int, int);
3131 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
3132 void sqlite3AppendSpace(StrAccum*,int);
3133 char *sqlite3StrAccumFinish(StrAccum*);
3134 void sqlite3StrAccumReset(StrAccum*);
3135 void sqlite3SelectDestInit(SelectDest*,int,int);
3136 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
3137 
3138 void sqlite3BackupRestart(sqlite3_backup *);
3139 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
3140 
3141 /*
3142 ** The interface to the LEMON-generated parser
3143 */
3144 void *sqlite3ParserAlloc(void*(*)(size_t));
3145 void sqlite3ParserFree(void*, void(*)(void*));
3146 void sqlite3Parser(void*, int, Token, Parse*);
3147 #ifdef YYTRACKMAXSTACKDEPTH
3148   int sqlite3ParserStackPeak(void*);
3149 #endif
3150 
3151 void sqlite3AutoLoadExtensions(sqlite3*);
3152 #ifndef SQLITE_OMIT_LOAD_EXTENSION
3153   void sqlite3CloseExtensions(sqlite3*);
3154 #else
3155 # define sqlite3CloseExtensions(X)
3156 #endif
3157 
3158 #ifndef SQLITE_OMIT_SHARED_CACHE
3159   void sqlite3TableLock(Parse *, int, int, u8, const char *);
3160 #else
3161   #define sqlite3TableLock(v,w,x,y,z)
3162 #endif
3163 
3164 #ifdef SQLITE_TEST
3165   int sqlite3Utf8To8(unsigned char*);
3166 #endif
3167 
3168 #ifdef SQLITE_OMIT_VIRTUALTABLE
3169 #  define sqlite3VtabClear(Y)
3170 #  define sqlite3VtabSync(X,Y) SQLITE_OK
3171 #  define sqlite3VtabRollback(X)
3172 #  define sqlite3VtabCommit(X)
3173 #  define sqlite3VtabInSync(db) 0
3174 #  define sqlite3VtabLock(X)
3175 #  define sqlite3VtabUnlock(X)
3176 #  define sqlite3VtabUnlockList(X)
3177 #  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
3178 #  define sqlite3GetVTable(X,Y)  ((VTable*)0)
3179 #else
3180    void sqlite3VtabClear(sqlite3 *db, Table*);
3181    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
3182    int sqlite3VtabSync(sqlite3 *db, char **);
3183    int sqlite3VtabRollback(sqlite3 *db);
3184    int sqlite3VtabCommit(sqlite3 *db);
3185    void sqlite3VtabLock(VTable *);
3186    void sqlite3VtabUnlock(VTable *);
3187    void sqlite3VtabUnlockList(sqlite3*);
3188    int sqlite3VtabSavepoint(sqlite3 *, int, int);
3189    VTable *sqlite3GetVTable(sqlite3*, Table*);
3190 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
3191 #endif
3192 void sqlite3VtabMakeWritable(Parse*,Table*);
3193 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
3194 void sqlite3VtabFinishParse(Parse*, Token*);
3195 void sqlite3VtabArgInit(Parse*);
3196 void sqlite3VtabArgExtend(Parse*, Token*);
3197 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
3198 int sqlite3VtabCallConnect(Parse*, Table*);
3199 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
3200 int sqlite3VtabBegin(sqlite3 *, VTable *);
3201 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
3202 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
3203 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
3204 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
3205 int sqlite3Reprepare(Vdbe*);
3206 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
3207 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
3208 int sqlite3TempInMemory(const sqlite3*);
3209 const char *sqlite3JournalModename(int);
3210 #ifndef SQLITE_OMIT_WAL
3211   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
3212   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
3213 #endif
3214 
3215 /* Declarations for functions in fkey.c. All of these are replaced by
3216 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
3217 ** key functionality is available. If OMIT_TRIGGER is defined but
3218 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
3219 ** this case foreign keys are parsed, but no other functionality is
3220 ** provided (enforcement of FK constraints requires the triggers sub-system).
3221 */
3222 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
3223   void sqlite3FkCheck(Parse*, Table*, int, int);
3224   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
3225   void sqlite3FkActions(Parse*, Table*, ExprList*, int);
3226   int sqlite3FkRequired(Parse*, Table*, int*, int);
3227   u32 sqlite3FkOldmask(Parse*, Table*);
3228   FKey *sqlite3FkReferences(Table *);
3229 #else
3230   #define sqlite3FkActions(a,b,c,d)
3231   #define sqlite3FkCheck(a,b,c,d)
3232   #define sqlite3FkDropTable(a,b,c)
3233   #define sqlite3FkOldmask(a,b)      0
3234   #define sqlite3FkRequired(a,b,c,d) 0
3235 #endif
3236 #ifndef SQLITE_OMIT_FOREIGN_KEY
3237   void sqlite3FkDelete(sqlite3 *, Table*);
3238   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
3239 #else
3240   #define sqlite3FkDelete(a,b)
3241   #define sqlite3FkLocateIndex(a,b,c,d,e)
3242 #endif
3243 
3244 
3245 /*
3246 ** Available fault injectors.  Should be numbered beginning with 0.
3247 */
3248 #define SQLITE_FAULTINJECTOR_MALLOC     0
3249 #define SQLITE_FAULTINJECTOR_COUNT      1
3250 
3251 /*
3252 ** The interface to the code in fault.c used for identifying "benign"
3253 ** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
3254 ** is not defined.
3255 */
3256 #ifndef SQLITE_OMIT_BUILTIN_TEST
3257   void sqlite3BeginBenignMalloc(void);
3258   void sqlite3EndBenignMalloc(void);
3259 #else
3260   #define sqlite3BeginBenignMalloc()
3261   #define sqlite3EndBenignMalloc()
3262 #endif
3263 
3264 #define IN_INDEX_ROWID           1
3265 #define IN_INDEX_EPH             2
3266 #define IN_INDEX_INDEX_ASC       3
3267 #define IN_INDEX_INDEX_DESC      4
3268 int sqlite3FindInIndex(Parse *, Expr *, int*);
3269 
3270 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
3271   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
3272   int sqlite3JournalSize(sqlite3_vfs *);
3273   int sqlite3JournalCreate(sqlite3_file *);
3274   int sqlite3JournalExists(sqlite3_file *p);
3275 #else
3276   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
3277   #define sqlite3JournalExists(p) 1
3278 #endif
3279 
3280 void sqlite3MemJournalOpen(sqlite3_file *);
3281 int sqlite3MemJournalSize(void);
3282 int sqlite3IsMemJournal(sqlite3_file *);
3283 
3284 #if SQLITE_MAX_EXPR_DEPTH>0
3285   void sqlite3ExprSetHeight(Parse *pParse, Expr *p);
3286   int sqlite3SelectExprHeight(Select *);
3287   int sqlite3ExprCheckHeight(Parse*, int);
3288 #else
3289   #define sqlite3ExprSetHeight(x,y)
3290   #define sqlite3SelectExprHeight(x) 0
3291   #define sqlite3ExprCheckHeight(x,y)
3292 #endif
3293 
3294 u32 sqlite3Get4byte(const u8*);
3295 void sqlite3Put4byte(u8*, u32);
3296 
3297 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
3298   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
3299   void sqlite3ConnectionUnlocked(sqlite3 *db);
3300   void sqlite3ConnectionClosed(sqlite3 *db);
3301 #else
3302   #define sqlite3ConnectionBlocked(x,y)
3303   #define sqlite3ConnectionUnlocked(x)
3304   #define sqlite3ConnectionClosed(x)
3305 #endif
3306 
3307 #ifdef SQLITE_DEBUG
3308   void sqlite3ParserTrace(FILE*, char *);
3309 #endif
3310 
3311 /*
3312 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
3313 ** sqlite3IoTrace is a pointer to a printf-like routine used to
3314 ** print I/O tracing messages.
3315 */
3316 #ifdef SQLITE_ENABLE_IOTRACE
3317 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
3318   void sqlite3VdbeIOTraceSql(Vdbe*);
3319 SQLITE_EXTERN void (*sqlite3IoTrace)(const char*,...);
3320 #else
3321 # define IOTRACE(A)
3322 # define sqlite3VdbeIOTraceSql(X)
3323 #endif
3324 
3325 /*
3326 ** These routines are available for the mem2.c debugging memory allocator
3327 ** only.  They are used to verify that different "types" of memory
3328 ** allocations are properly tracked by the system.
3329 **
3330 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
3331 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
3332 ** a single bit set.
3333 **
3334 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
3335 ** argument match the type set by the previous sqlite3MemdebugSetType().
3336 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
3337 **
3338 ** sqlite3MemdebugNoType() returns true if none of the bits in its second
3339 ** argument match the type set by the previous sqlite3MemdebugSetType().
3340 **
3341 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
3342 ** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
3343 ** it might have been allocated by lookaside, except the allocation was
3344 ** too large or lookaside was already full.  It is important to verify
3345 ** that allocations that might have been satisfied by lookaside are not
3346 ** passed back to non-lookaside free() routines.  Asserts such as the
3347 ** example above are placed on the non-lookaside free() routines to verify
3348 ** this constraint.
3349 **
3350 ** All of this is no-op for a production build.  It only comes into
3351 ** play when the SQLITE_MEMDEBUG compile-time option is used.
3352 */
3353 #ifdef SQLITE_MEMDEBUG
3354   void sqlite3MemdebugSetType(void*,u8);
3355   int sqlite3MemdebugHasType(void*,u8);
3356   int sqlite3MemdebugNoType(void*,u8);
3357 #else
3358 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
3359 # define sqlite3MemdebugHasType(X,Y)  1
3360 # define sqlite3MemdebugNoType(X,Y)   1
3361 #endif
3362 #define MEMTYPE_HEAP       0x01  /* General heap allocations */
3363 #define MEMTYPE_LOOKASIDE  0x02  /* Might have been lookaside memory */
3364 #define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
3365 #define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
3366 #define MEMTYPE_DB         0x10  /* Uses sqlite3DbMalloc, not sqlite_malloc */
3367 
3368 #endif /* _SQLITEINT_H_ */
3369