xref: /sqlite-3.40.0/src/sqliteInt.h (revision 1c826650)
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 ** @(#) $Id: sqliteInt.h,v 1.771 2008/09/04 17:17:39 danielk1977 Exp $
15 */
16 #ifndef _SQLITEINT_H_
17 #define _SQLITEINT_H_
18 
19 /*
20 ** Include the configuration header output by 'configure' if we're using the
21 ** autoconf-based build
22 */
23 #ifdef _HAVE_SQLITE_CONFIG_H
24 #include "config.h"
25 #endif
26 
27 #include "sqliteLimit.h"
28 
29 /* Disable nuisance warnings on Borland compilers */
30 #if defined(__BORLANDC__)
31 #pragma warn -rch /* unreachable code */
32 #pragma warn -ccc /* Condition is always true or false */
33 #pragma warn -aus /* Assigned value is never used */
34 #pragma warn -csu /* Comparing signed and unsigned */
35 #pragma warn -spa /* Suspicous pointer arithmetic */
36 #endif
37 
38 /* Needed for various definitions... */
39 #ifndef _GNU_SOURCE
40 # define _GNU_SOURCE
41 #endif
42 
43 /*
44 ** Include standard header files as necessary
45 */
46 #ifdef HAVE_STDINT_H
47 #include <stdint.h>
48 #endif
49 #ifdef HAVE_INTTYPES_H
50 #include <inttypes.h>
51 #endif
52 
53 /*
54 ** A macro used to aid in coverage testing.  When doing coverage
55 ** testing, the condition inside the argument must be evaluated
56 ** both true and false in order to get full branch coverage.
57 ** This macro can be inserted to ensure adequate test coverage
58 ** in places where simple condition/decision coverage is inadequate.
59 */
60 #ifdef SQLITE_COVERAGE_TEST
61   void sqlite3Coverage(int);
62 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
63 #else
64 # define testcase(X)
65 #endif
66 
67 /*
68 ** The ALWAYS and NEVER macros surround boolean expressions which
69 ** are intended to always be true or false, respectively.  Such
70 ** expressions could be omitted from the code completely.  But they
71 ** are included in a few cases in order to enhance the resilience
72 ** of SQLite to unexpected behavior - to make the code "self-healing"
73 ** or "ductile" rather than being "brittle" and crashing at the first
74 ** hint of unplanned behavior.
75 **
76 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
77 ** be true and false so that the unreachable code then specify will
78 ** not be counted as untested code.
79 */
80 #ifdef SQLITE_COVERAGE_TEST
81 # define ALWAYS(X)      (1)
82 # define NEVER(X)       (0)
83 #else
84 # define ALWAYS(X)      (X)
85 # define NEVER(X)       (X)
86 #endif
87 
88 /*
89 ** The macro unlikely() is a hint that surrounds a boolean
90 ** expression that is usually false.  Macro likely() surrounds
91 ** a boolean expression that is usually true.  GCC is able to
92 ** use these hints to generate better code, sometimes.
93 */
94 #if defined(__GNUC__) && 0
95 # define likely(X)    __builtin_expect((X),1)
96 # define unlikely(X)  __builtin_expect((X),0)
97 #else
98 # define likely(X)    !!(X)
99 # define unlikely(X)  !!(X)
100 #endif
101 
102 /*
103  * This macro is used to "hide" some ugliness in casting an int
104  * value to a ptr value under the MSVC 64-bit compiler.   Casting
105  * non 64-bit values to ptr types results in a "hard" error with
106  * the MSVC 64-bit compiler which this attempts to avoid.
107  *
108  * A simple compiler pragma or casting sequence could not be found
109  * to correct this in all situations, so this macro was introduced.
110  *
111  * It could be argued that the intptr_t type could be used in this
112  * case, but that type is not available on all compilers, or
113  * requires the #include of specific headers which differs between
114  * platforms.
115  */
116 #define SQLITE_INT_TO_PTR(X)   ((void*)&((char*)0)[X])
117 #define SQLITE_PTR_TO_INT(X)   ((int)(((char*)X)-(char*)0))
118 
119 /*
120 ** These #defines should enable >2GB file support on Posix if the
121 ** underlying operating system supports it.  If the OS lacks
122 ** large file support, or if the OS is windows, these should be no-ops.
123 **
124 ** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
125 ** system #includes.  Hence, this block of code must be the very first
126 ** code in all source files.
127 **
128 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
129 ** on the compiler command line.  This is necessary if you are compiling
130 ** on a recent machine (ex: RedHat 7.2) but you want your code to work
131 ** on an older machine (ex: RedHat 6.0).  If you compile on RedHat 7.2
132 ** without this option, LFS is enable.  But LFS does not exist in the kernel
133 ** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
134 ** portability you should omit LFS.
135 **
136 ** Similar is true for MacOS.  LFS is only supported on MacOS 9 and later.
137 */
138 #ifndef SQLITE_DISABLE_LFS
139 # define _LARGE_FILE       1
140 # ifndef _FILE_OFFSET_BITS
141 #   define _FILE_OFFSET_BITS 64
142 # endif
143 # define _LARGEFILE_SOURCE 1
144 #endif
145 
146 
147 /*
148 ** The SQLITE_THREADSAFE macro must be defined as either 0 or 1.
149 ** Older versions of SQLite used an optional THREADSAFE macro.
150 ** We support that for legacy
151 */
152 #if !defined(SQLITE_THREADSAFE)
153 #if defined(THREADSAFE)
154 # define SQLITE_THREADSAFE THREADSAFE
155 #else
156 # define SQLITE_THREADSAFE 1
157 #endif
158 #endif
159 
160 /*
161 ** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
162 ** It determines whether or not the features related to
163 ** SQLITE_CONFIG_MEMSTATUS are availabe by default or not. This value can
164 ** be overridden at runtime using the sqlite3_config() API.
165 */
166 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
167 # define SQLITE_DEFAULT_MEMSTATUS 1
168 #endif
169 
170 /*
171 ** Exactly one of the following macros must be defined in order to
172 ** specify which memory allocation subsystem to use.
173 **
174 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
175 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
176 **     SQLITE_MEMORY_SIZE            // internal allocator #1
177 **     SQLITE_MMAP_HEAP_SIZE         // internal mmap() allocator
178 **     SQLITE_POW2_MEMORY_SIZE       // internal power-of-two allocator
179 **
180 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
181 ** the default.
182 */
183 #if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_MEMDEBUG)+\
184     defined(SQLITE_MEMORY_SIZE)+defined(SQLITE_MMAP_HEAP_SIZE)+\
185     defined(SQLITE_POW2_MEMORY_SIZE)>1
186 # error "At most one of the following compile-time configuration options\
187  is allows: SQLITE_SYSTEM_MALLOC, SQLITE_MEMDEBUG, SQLITE_MEMORY_SIZE,\
188  SQLITE_MMAP_HEAP_SIZE, SQLITE_POW2_MEMORY_SIZE"
189 #endif
190 #if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_MEMDEBUG)+\
191     defined(SQLITE_MEMORY_SIZE)+defined(SQLITE_MMAP_HEAP_SIZE)+\
192     defined(SQLITE_POW2_MEMORY_SIZE)==0
193 # define SQLITE_SYSTEM_MALLOC 1
194 #endif
195 
196 /*
197 ** If SQLITE_MALLOC_SOFT_LIMIT is defined, then try to keep the
198 ** sizes of memory allocations below this value where possible.
199 */
200 #if defined(SQLITE_POW2_MEMORY_SIZE) && !defined(SQLITE_MALLOC_SOFT_LIMIT)
201 # define SQLITE_MALLOC_SOFT_LIMIT 1024
202 #endif
203 
204 /*
205 ** We need to define _XOPEN_SOURCE as follows in order to enable
206 ** recursive mutexes on most unix systems.  But Mac OS X is different.
207 ** The _XOPEN_SOURCE define causes problems for Mac OS X we are told,
208 ** so it is omitted there.  See ticket #2673.
209 **
210 ** Later we learn that _XOPEN_SOURCE is poorly or incorrectly
211 ** implemented on some systems.  So we avoid defining it at all
212 ** if it is already defined or if it is unneeded because we are
213 ** not doing a threadsafe build.  Ticket #2681.
214 **
215 ** See also ticket #2741.
216 */
217 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE
218 #  define _XOPEN_SOURCE 500  /* Needed to enable pthread recursive mutexes */
219 #endif
220 
221 /*
222 ** The TCL headers are only needed when compiling the TCL bindings.
223 */
224 #if defined(SQLITE_TCL) || defined(TCLSH)
225 # include <tcl.h>
226 #endif
227 
228 /*
229 ** Many people are failing to set -DNDEBUG=1 when compiling SQLite.
230 ** Setting NDEBUG makes the code smaller and run faster.  So the following
231 ** lines are added to automatically set NDEBUG unless the -DSQLITE_DEBUG=1
232 ** option is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
233 ** feature.
234 */
235 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
236 # define NDEBUG 1
237 #endif
238 
239 #include "sqlite3.h"
240 #include "hash.h"
241 #include "parse.h"
242 #include <stdio.h>
243 #include <stdlib.h>
244 #include <string.h>
245 #include <assert.h>
246 #include <stddef.h>
247 
248 /*
249 ** If compiling for a processor that lacks floating point support,
250 ** substitute integer for floating-point
251 */
252 #ifdef SQLITE_OMIT_FLOATING_POINT
253 # define double sqlite_int64
254 # define LONGDOUBLE_TYPE sqlite_int64
255 # ifndef SQLITE_BIG_DBL
256 #   define SQLITE_BIG_DBL (0x7fffffffffffffff)
257 # endif
258 # define SQLITE_OMIT_DATETIME_FUNCS 1
259 # define SQLITE_OMIT_TRACE 1
260 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
261 #endif
262 #ifndef SQLITE_BIG_DBL
263 # define SQLITE_BIG_DBL (1e99)
264 #endif
265 
266 /*
267 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
268 ** afterward. Having this macro allows us to cause the C compiler
269 ** to omit code used by TEMP tables without messy #ifndef statements.
270 */
271 #ifdef SQLITE_OMIT_TEMPDB
272 #define OMIT_TEMPDB 1
273 #else
274 #define OMIT_TEMPDB 0
275 #endif
276 
277 /*
278 ** If the following macro is set to 1, then NULL values are considered
279 ** distinct when determining whether or not two entries are the same
280 ** in a UNIQUE index.  This is the way PostgreSQL, Oracle, DB2, MySQL,
281 ** OCELOT, and Firebird all work.  The SQL92 spec explicitly says this
282 ** is the way things are suppose to work.
283 **
284 ** If the following macro is set to 0, the NULLs are indistinct for
285 ** a UNIQUE index.  In this mode, you can only have a single NULL entry
286 ** for a column declared UNIQUE.  This is the way Informix and SQL Server
287 ** work.
288 */
289 #define NULL_DISTINCT_FOR_UNIQUE 1
290 
291 /*
292 ** The "file format" number is an integer that is incremented whenever
293 ** the VDBE-level file format changes.  The following macros define the
294 ** the default file format for new databases and the maximum file format
295 ** that the library can read.
296 */
297 #define SQLITE_MAX_FILE_FORMAT 4
298 #ifndef SQLITE_DEFAULT_FILE_FORMAT
299 # define SQLITE_DEFAULT_FILE_FORMAT 1
300 #endif
301 
302 /*
303 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
304 ** on the command-line
305 */
306 #ifndef SQLITE_TEMP_STORE
307 # define SQLITE_TEMP_STORE 1
308 #endif
309 
310 /*
311 ** GCC does not define the offsetof() macro so we'll have to do it
312 ** ourselves.
313 */
314 #ifndef offsetof
315 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
316 #endif
317 
318 /*
319 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
320 ** not, there are still machines out there that use EBCDIC.)
321 */
322 #if 'A' == '\301'
323 # define SQLITE_EBCDIC 1
324 #else
325 # define SQLITE_ASCII 1
326 #endif
327 
328 /*
329 ** Integers of known sizes.  These typedefs might change for architectures
330 ** where the sizes very.  Preprocessor macros are available so that the
331 ** types can be conveniently redefined at compile-type.  Like this:
332 **
333 **         cc '-DUINTPTR_TYPE=long long int' ...
334 */
335 #ifndef UINT32_TYPE
336 # ifdef HAVE_UINT32_T
337 #  define UINT32_TYPE uint32_t
338 # else
339 #  define UINT32_TYPE unsigned int
340 # endif
341 #endif
342 #ifndef UINT16_TYPE
343 # ifdef HAVE_UINT16_T
344 #  define UINT16_TYPE uint16_t
345 # else
346 #  define UINT16_TYPE unsigned short int
347 # endif
348 #endif
349 #ifndef INT16_TYPE
350 # ifdef HAVE_INT16_T
351 #  define INT16_TYPE int16_t
352 # else
353 #  define INT16_TYPE short int
354 # endif
355 #endif
356 #ifndef UINT8_TYPE
357 # ifdef HAVE_UINT8_T
358 #  define UINT8_TYPE uint8_t
359 # else
360 #  define UINT8_TYPE unsigned char
361 # endif
362 #endif
363 #ifndef INT8_TYPE
364 # ifdef HAVE_INT8_T
365 #  define INT8_TYPE int8_t
366 # else
367 #  define INT8_TYPE signed char
368 # endif
369 #endif
370 #ifndef LONGDOUBLE_TYPE
371 # define LONGDOUBLE_TYPE long double
372 #endif
373 typedef sqlite_int64 i64;          /* 8-byte signed integer */
374 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
375 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
376 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
377 typedef INT16_TYPE i16;            /* 2-byte signed integer */
378 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
379 typedef INT8_TYPE i8;              /* 1-byte signed integer */
380 
381 /*
382 ** Macros to determine whether the machine is big or little endian,
383 ** evaluated at runtime.
384 */
385 #ifdef SQLITE_AMALGAMATION
386 const int sqlite3one;
387 #else
388 extern const int sqlite3one;
389 #endif
390 #if defined(i386) || defined(__i386__) || defined(_M_IX86)
391 # define SQLITE_BIGENDIAN    0
392 # define SQLITE_LITTLEENDIAN 1
393 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
394 #else
395 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
396 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
397 # define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
398 #endif
399 
400 /*
401 ** Constants for the largest and smallest possible 64-bit signed integers.
402 ** These macros are designed to work correctly on both 32-bit and 64-bit
403 ** compilers.
404 */
405 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
406 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
407 
408 /*
409 ** An instance of the following structure is used to store the busy-handler
410 ** callback for a given sqlite handle.
411 **
412 ** The sqlite.busyHandler member of the sqlite struct contains the busy
413 ** callback for the database handle. Each pager opened via the sqlite
414 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
415 ** callback is currently invoked only from within pager.c.
416 */
417 typedef struct BusyHandler BusyHandler;
418 struct BusyHandler {
419   int (*xFunc)(void *,int);  /* The busy callback */
420   void *pArg;                /* First arg to busy callback */
421   int nBusy;                 /* Incremented with each busy call */
422 };
423 
424 /*
425 ** Name of the master database table.  The master database table
426 ** is a special table that holds the names and attributes of all
427 ** user tables and indices.
428 */
429 #define MASTER_NAME       "sqlite_master"
430 #define TEMP_MASTER_NAME  "sqlite_temp_master"
431 
432 /*
433 ** The root-page of the master database table.
434 */
435 #define MASTER_ROOT       1
436 
437 /*
438 ** The name of the schema table.
439 */
440 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
441 
442 /*
443 ** A convenience macro that returns the number of elements in
444 ** an array.
445 */
446 #define ArraySize(X)    (sizeof(X)/sizeof(X[0]))
447 
448 /*
449 ** The following value as a destructor means to use sqlite3DbFree().
450 ** This is an internal extension to SQLITE_STATIC and SQLITE_TRANSIENT.
451 */
452 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3DbFree)
453 
454 /*
455 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
456 ** not support Writable Static Data (WSD) such as global and static variables.
457 ** All variables must either be on the stack or dynamically allocated from
458 ** the heap.  When WSD is unsupported, the variable declarations scattered
459 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
460 ** macro is used for this purpose.  And instead of referencing the variable
461 ** directly, we use its constant as a key to lookup the run-time allocated
462 ** buffer that holds real variable.  The constant is also the initializer
463 ** for the run-time allocated buffer.
464 **
465 ** In the usually case where WSD is supported, the SQLITE_WSD and GLOBAL
466 ** macros become no-ops and have zero performance impact.
467 */
468 #ifdef SQLITE_OMIT_WSD
469   #define SQLITE_WSD const
470   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
471   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
472 #else
473   #define SQLITE_WSD
474   #define GLOBAL(t,v) v
475   #define sqlite3GlobalConfig sqlite3Config
476 #endif
477 
478 /*
479 ** Forward references to structures
480 */
481 typedef struct AggInfo AggInfo;
482 typedef struct AuthContext AuthContext;
483 typedef struct Bitvec Bitvec;
484 typedef struct CollSeq CollSeq;
485 typedef struct Column Column;
486 typedef struct Db Db;
487 typedef struct Schema Schema;
488 typedef struct Expr Expr;
489 typedef struct ExprList ExprList;
490 typedef struct FKey FKey;
491 typedef struct FuncDef FuncDef;
492 typedef struct FuncDefHash FuncDefHash;
493 typedef struct IdList IdList;
494 typedef struct Index Index;
495 typedef struct KeyClass KeyClass;
496 typedef struct KeyInfo KeyInfo;
497 typedef struct Lookaside Lookaside;
498 typedef struct LookasideSlot LookasideSlot;
499 typedef struct Module Module;
500 typedef struct NameContext NameContext;
501 typedef struct Parse Parse;
502 typedef struct Select Select;
503 typedef struct SrcList SrcList;
504 typedef struct StrAccum StrAccum;
505 typedef struct Table Table;
506 typedef struct TableLock TableLock;
507 typedef struct Token Token;
508 typedef struct TriggerStack TriggerStack;
509 typedef struct TriggerStep TriggerStep;
510 typedef struct Trigger Trigger;
511 typedef struct UnpackedRecord UnpackedRecord;
512 typedef struct Walker Walker;
513 typedef struct WhereInfo WhereInfo;
514 typedef struct WhereLevel WhereLevel;
515 
516 /*
517 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
518 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
519 ** pointer types (i.e. FuncDef) defined above.
520 */
521 #include "btree.h"
522 #include "vdbe.h"
523 #include "pager.h"
524 #include "pcache.h"
525 
526 #include "os.h"
527 #include "mutex.h"
528 
529 
530 /*
531 ** Each database file to be accessed by the system is an instance
532 ** of the following structure.  There are normally two of these structures
533 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
534 ** aDb[1] is the database file used to hold temporary tables.  Additional
535 ** databases may be attached.
536 */
537 struct Db {
538   char *zName;         /* Name of this database */
539   Btree *pBt;          /* The B*Tree structure for this database file */
540   u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
541   u8 safety_level;     /* How aggressive at synching data to disk */
542   void *pAux;               /* Auxiliary data.  Usually NULL */
543   void (*xFreeAux)(void*);  /* Routine to free pAux */
544   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
545 };
546 
547 /*
548 ** An instance of the following structure stores a database schema.
549 **
550 ** If there are no virtual tables configured in this schema, the
551 ** Schema.db variable is set to NULL. After the first virtual table
552 ** has been added, it is set to point to the database connection
553 ** used to create the connection. Once a virtual table has been
554 ** added to the Schema structure and the Schema.db variable populated,
555 ** only that database connection may use the Schema to prepare
556 ** statements.
557 */
558 struct Schema {
559   int schema_cookie;   /* Database schema version number for this file */
560   Hash tblHash;        /* All tables indexed by name */
561   Hash idxHash;        /* All (named) indices indexed by name */
562   Hash trigHash;       /* All triggers indexed by name */
563   Hash aFKey;          /* Foreign keys indexed by to-table */
564   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
565   u8 file_format;      /* Schema format version for this file */
566   u8 enc;              /* Text encoding used by this database */
567   u16 flags;           /* Flags associated with this schema */
568   int cache_size;      /* Number of pages to use in the cache */
569 #ifndef SQLITE_OMIT_VIRTUALTABLE
570   sqlite3 *db;         /* "Owner" connection. See comment above */
571 #endif
572 };
573 
574 /*
575 ** These macros can be used to test, set, or clear bits in the
576 ** Db.flags field.
577 */
578 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->flags&(P))==(P))
579 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->flags&(P))!=0)
580 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->flags|=(P)
581 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->flags&=~(P)
582 
583 /*
584 ** Allowed values for the DB.flags field.
585 **
586 ** The DB_SchemaLoaded flag is set after the database schema has been
587 ** read into internal hash tables.
588 **
589 ** DB_UnresetViews means that one or more views have column names that
590 ** have been filled out.  If the schema changes, these column names might
591 ** changes and so the view will need to be reset.
592 */
593 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
594 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
595 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
596 
597 /*
598 ** The number of different kinds of things that can be limited
599 ** using the sqlite3_limit() interface.
600 */
601 #define SQLITE_N_LIMIT (SQLITE_LIMIT_VARIABLE_NUMBER+1)
602 
603 /*
604 ** Lookaside malloc is a set of fixed-size buffers that can be used
605 ** to satisify small transient memory allocation requests for objects
606 ** associated with a particular database connection.  The use of
607 ** lookaside malloc provides a significant performance enhancement
608 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
609 ** SQL statements.
610 **
611 ** The Lookaside structure holds configuration information about the
612 ** lookaside malloc subsystem.  Each available memory allocation in
613 ** the lookaside subsystem is stored on a linked list of LookasideSlot
614 ** objects.
615 */
616 struct Lookaside {
617   u16 sz;                 /* Size of each buffer in bytes */
618   u8 bEnabled;            /* True if use lookaside.  False to ignore it */
619   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
620   int nOut;               /* Number of buffers currently checked out */
621   int mxOut;              /* Highwater mark for nOut */
622   LookasideSlot *pFree;   /* List of available buffers */
623   void *pStart;           /* First byte of available memory space */
624   void *pEnd;             /* First byte past end of available space */
625 };
626 struct LookasideSlot {
627   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
628 };
629 
630 /*
631 ** A hash table for function definitions.
632 **
633 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
634 ** Collisions are on the FuncDef.pHash chain.
635 */
636 struct FuncDefHash {
637   FuncDef *a[23];       /* Hash table for functions */
638 };
639 
640 /*
641 ** Each database is an instance of the following structure.
642 **
643 ** The sqlite.lastRowid records the last insert rowid generated by an
644 ** insert statement.  Inserts on views do not affect its value.  Each
645 ** trigger has its own context, so that lastRowid can be updated inside
646 ** triggers as usual.  The previous value will be restored once the trigger
647 ** exits.  Upon entering a before or instead of trigger, lastRowid is no
648 ** longer (since after version 2.8.12) reset to -1.
649 **
650 ** The sqlite.nChange does not count changes within triggers and keeps no
651 ** context.  It is reset at start of sqlite3_exec.
652 ** The sqlite.lsChange represents the number of changes made by the last
653 ** insert, update, or delete statement.  It remains constant throughout the
654 ** length of a statement and is then updated by OP_SetCounts.  It keeps a
655 ** context stack just like lastRowid so that the count of changes
656 ** within a trigger is not seen outside the trigger.  Changes to views do not
657 ** affect the value of lsChange.
658 ** The sqlite.csChange keeps track of the number of current changes (since
659 ** the last statement) and is used to update sqlite_lsChange.
660 **
661 ** The member variables sqlite.errCode, sqlite.zErrMsg and sqlite.zErrMsg16
662 ** store the most recent error code and, if applicable, string. The
663 ** internal function sqlite3Error() is used to set these variables
664 ** consistently.
665 */
666 struct sqlite3 {
667   sqlite3_vfs *pVfs;            /* OS Interface */
668   int nDb;                      /* Number of backends currently in use */
669   Db *aDb;                      /* All backends */
670   int flags;                    /* Miscellanous flags. See below */
671   int openFlags;                /* Flags passed to sqlite3_vfs.xOpen() */
672   int errCode;                  /* Most recent error code (SQLITE_*) */
673   int errMask;                  /* & result codes with this before returning */
674   u8 autoCommit;                /* The auto-commit flag. */
675   u8 temp_store;                /* 1: file 2: memory 0: default */
676   u8 mallocFailed;              /* True if we have seen a malloc failure */
677   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
678   u8 dfltJournalMode;           /* Default journal mode for attached dbs */
679   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
680   int nextPagesize;             /* Pagesize after VACUUM if >0 */
681   int nTable;                   /* Number of tables in the database */
682   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
683   i64 lastRowid;                /* ROWID of most recent insert (see above) */
684   i64 priorNewRowid;            /* Last randomly generated ROWID */
685   int magic;                    /* Magic number for detect library misuse */
686   int nChange;                  /* Value returned by sqlite3_changes() */
687   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
688   sqlite3_mutex *mutex;         /* Connection mutex */
689   int aLimit[SQLITE_N_LIMIT];   /* Limits */
690   struct sqlite3InitInfo {      /* Information used during initialization */
691     int iDb;                    /* When back is being initialized */
692     int newTnum;                /* Rootpage of table being initialized */
693     u8 busy;                    /* TRUE if currently initializing */
694   } init;
695   int nExtension;               /* Number of loaded extensions */
696   void **aExtension;            /* Array of shared libraray handles */
697   struct Vdbe *pVdbe;           /* List of active virtual machines */
698   int activeVdbeCnt;            /* Number of vdbes currently executing */
699   void (*xTrace)(void*,const char*);        /* Trace function */
700   void *pTraceArg;                          /* Argument to the trace function */
701   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
702   void *pProfileArg;                        /* Argument to profile function */
703   void *pCommitArg;                 /* Argument to xCommitCallback() */
704   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
705   void *pRollbackArg;               /* Argument to xRollbackCallback() */
706   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
707   void *pUpdateArg;
708   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
709   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
710   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
711   void *pCollNeededArg;
712   sqlite3_value *pErr;          /* Most recent error message */
713   char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
714   char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
715   union {
716     int isInterrupted;          /* True if sqlite3_interrupt has been called */
717     double notUsed1;            /* Spacer */
718   } u1;
719   Lookaside lookaside;          /* Lookaside malloc configuration */
720 #ifndef SQLITE_OMIT_AUTHORIZATION
721   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
722                                 /* Access authorization function */
723   void *pAuthArg;               /* 1st argument to the access auth function */
724 #endif
725 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
726   int (*xProgress)(void *);     /* The progress callback */
727   void *pProgressArg;           /* Argument to the progress callback */
728   int nProgressOps;             /* Number of opcodes for progress callback */
729 #endif
730 #ifndef SQLITE_OMIT_VIRTUALTABLE
731   Hash aModule;                 /* populated by sqlite3_create_module() */
732   Table *pVTab;                 /* vtab with active Connect/Create method */
733   sqlite3_vtab **aVTrans;       /* Virtual tables with open transactions */
734   int nVTrans;                  /* Allocated size of aVTrans */
735 #endif
736   FuncDefHash aFunc;            /* Hash table of connection functions */
737   Hash aCollSeq;                /* All collating sequences */
738   BusyHandler busyHandler;      /* Busy callback */
739   int busyTimeout;              /* Busy handler timeout, in msec */
740   Db aDbStatic[2];              /* Static space for the 2 default backends */
741 #ifdef SQLITE_SSE
742   sqlite3_stmt *pFetch;         /* Used by SSE to fetch stored statements */
743 #endif
744 };
745 
746 /*
747 ** A macro to discover the encoding of a database.
748 */
749 #define ENC(db) ((db)->aDb[0].pSchema->enc)
750 
751 /*
752 ** Possible values for the sqlite.flags and or Db.flags fields.
753 **
754 ** On sqlite.flags, the SQLITE_InTrans value means that we have
755 ** executed a BEGIN.  On Db.flags, SQLITE_InTrans means a statement
756 ** transaction is active on that particular database file.
757 */
758 #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
759 #define SQLITE_InTrans        0x00000008  /* True if in a transaction */
760 #define SQLITE_InternChanges  0x00000010  /* Uncommitted Hash table changes */
761 #define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
762 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
763 #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
764                                           /*   DELETE, or UPDATE and return */
765                                           /*   the count using a callback. */
766 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
767                                           /*   result set is empty */
768 #define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
769 #define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
770 #define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
771 #define SQLITE_NoReadlock     0x00001000  /* Readlocks are omitted when
772                                           ** accessing read-only databases */
773 #define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
774 #define SQLITE_ReadUncommitted 0x00004000 /* For shared-cache mode */
775 #define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
776 #define SQLITE_FullFSync      0x00010000  /* Use full fsync on the backend */
777 #define SQLITE_LoadExtension  0x00020000  /* Enable load_extension */
778 
779 #define SQLITE_RecoveryMode   0x00040000  /* Ignore schema errors */
780 #define SQLITE_SharedCache    0x00080000  /* Cache sharing is enabled */
781 #define SQLITE_Vtab           0x00100000  /* There exists a virtual table */
782 
783 /*
784 ** Possible values for the sqlite.magic field.
785 ** The numbers are obtained at random and have no special meaning, other
786 ** than being distinct from one another.
787 */
788 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
789 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
790 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
791 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
792 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
793 
794 /*
795 ** Each SQL function is defined by an instance of the following
796 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
797 ** hash table.  When multiple functions have the same name, the hash table
798 ** points to a linked list of these structures.
799 */
800 struct FuncDef {
801   i8 nArg;             /* Number of arguments.  -1 means unlimited */
802   u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
803   u8 needCollSeq;      /* True if sqlite3GetFuncCollSeq() might be called */
804   u8 flags;            /* Some combination of SQLITE_FUNC_* */
805   void *pUserData;     /* User data parameter */
806   FuncDef *pNext;      /* Next function with same name */
807   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
808   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
809   void (*xFinalize)(sqlite3_context*);                /* Aggregate finializer */
810   char *zName;         /* SQL name of the function. */
811   FuncDef *pHash;      /* Next with a different name but the same hash */
812 };
813 
814 /*
815 ** Possible values for FuncDef.flags
816 */
817 #define SQLITE_FUNC_LIKE     0x01  /* Candidate for the LIKE optimization */
818 #define SQLITE_FUNC_CASE     0x02  /* Case-sensitive LIKE-type function */
819 #define SQLITE_FUNC_EPHEM    0x04  /* Ephermeral.  Delete with VDBE */
820 
821 /*
822 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
823 ** used to create the initializers for the FuncDef structures.
824 **
825 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
826 **     Used to create a scalar function definition of a function zName
827 **     implemented by C function xFunc that accepts nArg arguments. The
828 **     value passed as iArg is cast to a (void*) and made available
829 **     as the user-data (sqlite3_user_data()) for the function. If
830 **     argument bNC is true, then the FuncDef.needCollate flag is set.
831 **
832 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
833 **     Used to create an aggregate function definition implemented by
834 **     the C functions xStep and xFinal. The first four parameters
835 **     are interpreted in the same way as the first 4 parameters to
836 **     FUNCTION().
837 **
838 **   LIKEFUNC(zName, nArg, pArg, flags)
839 **     Used to create a scalar function definition of a function zName
840 **     that accepts nArg arguments and is implemented by a call to C
841 **     function likeFunc. Argument pArg is cast to a (void *) and made
842 **     available as the function user-data (sqlite3_user_data()). The
843 **     FuncDef.flags variable is set to the value passed as the flags
844 **     parameter.
845 */
846 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
847   {nArg, SQLITE_UTF8, bNC, 0, SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName}
848 #define LIKEFUNC(zName, nArg, arg, flags) \
849   {nArg, SQLITE_UTF8, 0, flags, (void *)arg, 0, likeFunc, 0, 0, #zName}
850 #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
851   {nArg, SQLITE_UTF8, nc, 0, SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal, #zName}
852 
853 
854 /*
855 ** Each SQLite module (virtual table definition) is defined by an
856 ** instance of the following structure, stored in the sqlite3.aModule
857 ** hash table.
858 */
859 struct Module {
860   const sqlite3_module *pModule;       /* Callback pointers */
861   const char *zName;                   /* Name passed to create_module() */
862   void *pAux;                          /* pAux passed to create_module() */
863   void (*xDestroy)(void *);            /* Module destructor function */
864 };
865 
866 /*
867 ** information about each column of an SQL table is held in an instance
868 ** of this structure.
869 */
870 struct Column {
871   char *zName;     /* Name of this column */
872   Expr *pDflt;     /* Default value of this column */
873   char *zType;     /* Data type for this column */
874   char *zColl;     /* Collating sequence.  If NULL, use the default */
875   u8 notNull;      /* True if there is a NOT NULL constraint */
876   u8 isPrimKey;    /* True if this column is part of the PRIMARY KEY */
877   char affinity;   /* One of the SQLITE_AFF_... values */
878 #ifndef SQLITE_OMIT_VIRTUALTABLE
879   u8 isHidden;     /* True if this column is 'hidden' */
880 #endif
881 };
882 
883 /*
884 ** A "Collating Sequence" is defined by an instance of the following
885 ** structure. Conceptually, a collating sequence consists of a name and
886 ** a comparison routine that defines the order of that sequence.
887 **
888 ** There may two seperate implementations of the collation function, one
889 ** that processes text in UTF-8 encoding (CollSeq.xCmp) and another that
890 ** processes text encoded in UTF-16 (CollSeq.xCmp16), using the machine
891 ** native byte order. When a collation sequence is invoked, SQLite selects
892 ** the version that will require the least expensive encoding
893 ** translations, if any.
894 **
895 ** The CollSeq.pUser member variable is an extra parameter that passed in
896 ** as the first argument to the UTF-8 comparison function, xCmp.
897 ** CollSeq.pUser16 is the equivalent for the UTF-16 comparison function,
898 ** xCmp16.
899 **
900 ** If both CollSeq.xCmp and CollSeq.xCmp16 are NULL, it means that the
901 ** collating sequence is undefined.  Indices built on an undefined
902 ** collating sequence may not be read or written.
903 */
904 struct CollSeq {
905   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
906   u8 enc;               /* Text encoding handled by xCmp() */
907   u8 type;              /* One of the SQLITE_COLL_... values below */
908   void *pUser;          /* First argument to xCmp() */
909   int (*xCmp)(void*,int, const void*, int, const void*);
910   void (*xDel)(void*);  /* Destructor for pUser */
911 };
912 
913 /*
914 ** Allowed values of CollSeq.type:
915 */
916 #define SQLITE_COLL_BINARY  1  /* The default memcmp() collating sequence */
917 #define SQLITE_COLL_NOCASE  2  /* The built-in NOCASE collating sequence */
918 #define SQLITE_COLL_REVERSE 3  /* The built-in REVERSE collating sequence */
919 #define SQLITE_COLL_USER    0  /* Any other user-defined collating sequence */
920 
921 /*
922 ** A sort order can be either ASC or DESC.
923 */
924 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
925 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
926 
927 /*
928 ** Column affinity types.
929 **
930 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
931 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
932 ** the speed a little by numbering the values consecutively.
933 **
934 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
935 ** when multiple affinity types are concatenated into a string and
936 ** used as the P4 operand, they will be more readable.
937 **
938 ** Note also that the numeric types are grouped together so that testing
939 ** for a numeric type is a single comparison.
940 */
941 #define SQLITE_AFF_TEXT     'a'
942 #define SQLITE_AFF_NONE     'b'
943 #define SQLITE_AFF_NUMERIC  'c'
944 #define SQLITE_AFF_INTEGER  'd'
945 #define SQLITE_AFF_REAL     'e'
946 
947 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
948 
949 /*
950 ** The SQLITE_AFF_MASK values masks off the significant bits of an
951 ** affinity value.
952 */
953 #define SQLITE_AFF_MASK     0x67
954 
955 /*
956 ** Additional bit values that can be ORed with an affinity without
957 ** changing the affinity.
958 */
959 #define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
960 #define SQLITE_STOREP2      0x10  /* Store result in reg[P2] rather than jump */
961 
962 /*
963 ** Each SQL table is represented in memory by an instance of the
964 ** following structure.
965 **
966 ** Table.zName is the name of the table.  The case of the original
967 ** CREATE TABLE statement is stored, but case is not significant for
968 ** comparisons.
969 **
970 ** Table.nCol is the number of columns in this table.  Table.aCol is a
971 ** pointer to an array of Column structures, one for each column.
972 **
973 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
974 ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
975 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
976 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
977 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
978 ** is generated for each row of the table.  TF_HasPrimaryKey is set if
979 ** the table has any PRIMARY KEY, INTEGER or otherwise.
980 **
981 ** Table.tnum is the page number for the root BTree page of the table in the
982 ** database file.  If Table.iDb is the index of the database table backend
983 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
984 ** holds temporary tables and indices.  If TF_Ephemeral is set
985 ** then the table is stored in a file that is automatically deleted
986 ** when the VDBE cursor to the table is closed.  In this case Table.tnum
987 ** refers VDBE cursor number that holds the table open, not to the root
988 ** page number.  Transient tables are used to hold the results of a
989 ** sub-query that appears instead of a real table name in the FROM clause
990 ** of a SELECT statement.
991 */
992 struct Table {
993   sqlite3 *db;         /* Associated database connection.  Might be NULL. */
994   char *zName;         /* Name of the table or view */
995   int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
996   int nCol;            /* Number of columns in this table */
997   Column *aCol;        /* Information about each column */
998   Index *pIndex;       /* List of SQL indexes on this table. */
999   int tnum;            /* Root BTree node for this table (see note above) */
1000   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
1001   u16 nRef;            /* Number of pointers to this Table */
1002   u8 tabFlags;         /* Mask of TF_* values */
1003   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
1004   Trigger *pTrigger;   /* List of SQL triggers on this table */
1005   FKey *pFKey;         /* Linked list of all foreign keys in this table */
1006   char *zColAff;       /* String defining the affinity of each column */
1007 #ifndef SQLITE_OMIT_CHECK
1008   Expr *pCheck;        /* The AND of all CHECK constraints */
1009 #endif
1010 #ifndef SQLITE_OMIT_ALTERTABLE
1011   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
1012 #endif
1013 #ifndef SQLITE_OMIT_VIRTUALTABLE
1014   Module *pMod;        /* Pointer to the implementation of the module */
1015   sqlite3_vtab *pVtab; /* Pointer to the module instance */
1016   int nModuleArg;      /* Number of arguments to the module */
1017   char **azModuleArg;  /* Text of all module args. [0] is module name */
1018 #endif
1019   Schema *pSchema;     /* Schema that contains this table */
1020   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
1021 };
1022 
1023 /*
1024 ** Allowed values for Tabe.tabFlags.
1025 */
1026 #define TF_Readonly        0x01    /* Read-only system table */
1027 #define TF_Ephemeral       0x02    /* An emphermal table */
1028 #define TF_HasPrimaryKey   0x04    /* Table has a primary key */
1029 #define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
1030 #define TF_Virtual         0x10    /* Is a virtual table */
1031 #define TF_NeedMetadata    0x20    /* aCol[].zType and aCol[].pColl missing */
1032 
1033 
1034 
1035 /*
1036 ** Test to see whether or not a table is a virtual table.  This is
1037 ** done as a macro so that it will be optimized out when virtual
1038 ** table support is omitted from the build.
1039 */
1040 #ifndef SQLITE_OMIT_VIRTUALTABLE
1041 #  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
1042 #  define IsHiddenColumn(X) ((X)->isHidden)
1043 #else
1044 #  define IsVirtual(X)      0
1045 #  define IsHiddenColumn(X) 0
1046 #endif
1047 
1048 /*
1049 ** Each foreign key constraint is an instance of the following structure.
1050 **
1051 ** A foreign key is associated with two tables.  The "from" table is
1052 ** the table that contains the REFERENCES clause that creates the foreign
1053 ** key.  The "to" table is the table that is named in the REFERENCES clause.
1054 ** Consider this example:
1055 **
1056 **     CREATE TABLE ex1(
1057 **       a INTEGER PRIMARY KEY,
1058 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
1059 **     );
1060 **
1061 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
1062 **
1063 ** Each REFERENCES clause generates an instance of the following structure
1064 ** which is attached to the from-table.  The to-table need not exist when
1065 ** the from-table is created.  The existance of the to-table is not checked
1066 ** until an attempt is made to insert data into the from-table.
1067 **
1068 ** The sqlite.aFKey hash table stores pointers to this structure
1069 ** given the name of a to-table.  For each to-table, all foreign keys
1070 ** associated with that table are on a linked list using the FKey.pNextTo
1071 ** field.
1072 */
1073 struct FKey {
1074   Table *pFrom;     /* The table that constains the REFERENCES clause */
1075   FKey *pNextFrom;  /* Next foreign key in pFrom */
1076   char *zTo;        /* Name of table that the key points to */
1077   FKey *pNextTo;    /* Next foreign key that points to zTo */
1078   int nCol;         /* Number of columns in this key */
1079   struct sColMap {  /* Mapping of columns in pFrom to columns in zTo */
1080     int iFrom;         /* Index of column in pFrom */
1081     char *zCol;        /* Name of column in zTo.  If 0 use PRIMARY KEY */
1082   } *aCol;          /* One entry for each of nCol column s */
1083   u8 isDeferred;    /* True if constraint checking is deferred till COMMIT */
1084   u8 updateConf;    /* How to resolve conflicts that occur on UPDATE */
1085   u8 deleteConf;    /* How to resolve conflicts that occur on DELETE */
1086   u8 insertConf;    /* How to resolve conflicts that occur on INSERT */
1087 };
1088 
1089 /*
1090 ** SQLite supports many different ways to resolve a constraint
1091 ** error.  ROLLBACK processing means that a constraint violation
1092 ** causes the operation in process to fail and for the current transaction
1093 ** to be rolled back.  ABORT processing means the operation in process
1094 ** fails and any prior changes from that one operation are backed out,
1095 ** but the transaction is not rolled back.  FAIL processing means that
1096 ** the operation in progress stops and returns an error code.  But prior
1097 ** changes due to the same operation are not backed out and no rollback
1098 ** occurs.  IGNORE means that the particular row that caused the constraint
1099 ** error is not inserted or updated.  Processing continues and no error
1100 ** is returned.  REPLACE means that preexisting database rows that caused
1101 ** a UNIQUE constraint violation are removed so that the new insert or
1102 ** update can proceed.  Processing continues and no error is reported.
1103 **
1104 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
1105 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
1106 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
1107 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
1108 ** referenced table row is propagated into the row that holds the
1109 ** foreign key.
1110 **
1111 ** The following symbolic values are used to record which type
1112 ** of action to take.
1113 */
1114 #define OE_None     0   /* There is no constraint to check */
1115 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
1116 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
1117 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
1118 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
1119 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
1120 
1121 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
1122 #define OE_SetNull  7   /* Set the foreign key value to NULL */
1123 #define OE_SetDflt  8   /* Set the foreign key value to its default */
1124 #define OE_Cascade  9   /* Cascade the changes */
1125 
1126 #define OE_Default  99  /* Do whatever the default action is */
1127 
1128 
1129 /*
1130 ** An instance of the following structure is passed as the first
1131 ** argument to sqlite3VdbeKeyCompare and is used to control the
1132 ** comparison of the two index keys.
1133 */
1134 struct KeyInfo {
1135   sqlite3 *db;        /* The database connection */
1136   u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
1137   u16 nField;         /* Number of entries in aColl[] */
1138   u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
1139   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
1140 };
1141 
1142 /*
1143 ** An instance of the following structure holds information about a
1144 ** single index record that has already been parsed out into individual
1145 ** values.
1146 **
1147 ** A record is an object that contains one or more fields of data.
1148 ** Records are used to store the content of a table row and to store
1149 ** the key of an index.  A blob encoding of a record is created by
1150 ** the OP_MakeRecord opcode of the VDBE and is disassemblied by the
1151 ** OP_Column opcode.
1152 **
1153 ** This structure holds a record that has already been disassembled
1154 ** into its constitutent fields.
1155 */
1156 struct UnpackedRecord {
1157   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
1158   u16 nField;         /* Number of entries in apMem[] */
1159   u16 flags;          /* Boolean settings.  UNPACKED_... below */
1160   Mem *aMem;          /* Values */
1161 };
1162 
1163 /*
1164 ** Allowed values of UnpackedRecord.flags
1165 */
1166 #define UNPACKED_NEED_FREE     0x0001  /* Memory is from sqlite3Malloc() */
1167 #define UNPACKED_NEED_DESTROY  0x0002  /* apMem[]s should all be destroyed */
1168 #define UNPACKED_IGNORE_ROWID  0x0004  /* Ignore trailing rowid on key1 */
1169 #define UNPACKED_INCRKEY       0x0008  /* Make this key an epsilon larger */
1170 #define UNPACKED_PREFIX_MATCH  0x0010  /* A prefix match is considered OK */
1171 
1172 /*
1173 ** Each SQL index is represented in memory by an
1174 ** instance of the following structure.
1175 **
1176 ** The columns of the table that are to be indexed are described
1177 ** by the aiColumn[] field of this structure.  For example, suppose
1178 ** we have the following table and index:
1179 **
1180 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
1181 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
1182 **
1183 ** In the Table structure describing Ex1, nCol==3 because there are
1184 ** three columns in the table.  In the Index structure describing
1185 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
1186 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
1187 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
1188 ** The second column to be indexed (c1) has an index of 0 in
1189 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
1190 **
1191 ** The Index.onError field determines whether or not the indexed columns
1192 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
1193 ** it means this is not a unique index.  Otherwise it is a unique index
1194 ** and the value of Index.onError indicate the which conflict resolution
1195 ** algorithm to employ whenever an attempt is made to insert a non-unique
1196 ** element.
1197 */
1198 struct Index {
1199   char *zName;     /* Name of this index */
1200   int nColumn;     /* Number of columns in the table used by this index */
1201   int *aiColumn;   /* Which columns are used by this index.  1st is 0 */
1202   unsigned *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
1203   Table *pTable;   /* The SQL table being indexed */
1204   int tnum;        /* Page containing root of this index in database file */
1205   u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
1206   u8 autoIndex;    /* True if is automatically created (ex: by UNIQUE) */
1207   char *zColAff;   /* String defining the affinity of each column */
1208   Index *pNext;    /* The next index associated with the same table */
1209   Schema *pSchema; /* Schema containing this index */
1210   u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
1211   char **azColl;   /* Array of collation sequence names for index */
1212 };
1213 
1214 /*
1215 ** Each token coming out of the lexer is an instance of
1216 ** this structure.  Tokens are also used as part of an expression.
1217 **
1218 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
1219 ** may contain random values.  Do not make any assuptions about Token.dyn
1220 ** and Token.n when Token.z==0.
1221 */
1222 struct Token {
1223   const unsigned char *z; /* Text of the token.  Not NULL-terminated! */
1224   unsigned dyn  : 1;      /* True for malloced memory, false for static */
1225   unsigned n    : 31;     /* Number of characters in this token */
1226 };
1227 
1228 /*
1229 ** An instance of this structure contains information needed to generate
1230 ** code for a SELECT that contains aggregate functions.
1231 **
1232 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
1233 ** pointer to this structure.  The Expr.iColumn field is the index in
1234 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
1235 ** code for that node.
1236 **
1237 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
1238 ** original Select structure that describes the SELECT statement.  These
1239 ** fields do not need to be freed when deallocating the AggInfo structure.
1240 */
1241 struct AggInfo {
1242   u8 directMode;          /* Direct rendering mode means take data directly
1243                           ** from source tables rather than from accumulators */
1244   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
1245                           ** than the source table */
1246   int sortingIdx;         /* Cursor number of the sorting index */
1247   ExprList *pGroupBy;     /* The group by clause */
1248   int nSortingColumn;     /* Number of columns in the sorting index */
1249   struct AggInfo_col {    /* For each column used in source tables */
1250     Table *pTab;             /* Source table */
1251     int iTable;              /* Cursor number of the source table */
1252     int iColumn;             /* Column number within the source table */
1253     int iSorterColumn;       /* Column number in the sorting index */
1254     int iMem;                /* Memory location that acts as accumulator */
1255     Expr *pExpr;             /* The original expression */
1256   } *aCol;
1257   int nColumn;            /* Number of used entries in aCol[] */
1258   int nColumnAlloc;       /* Number of slots allocated for aCol[] */
1259   int nAccumulator;       /* Number of columns that show through to the output.
1260                           ** Additional columns are used only as parameters to
1261                           ** aggregate functions */
1262   struct AggInfo_func {   /* For each aggregate function */
1263     Expr *pExpr;             /* Expression encoding the function */
1264     FuncDef *pFunc;          /* The aggregate function implementation */
1265     int iMem;                /* Memory location that acts as accumulator */
1266     int iDistinct;           /* Ephermeral table used to enforce DISTINCT */
1267   } *aFunc;
1268   int nFunc;              /* Number of entries in aFunc[] */
1269   int nFuncAlloc;         /* Number of slots allocated for aFunc[] */
1270 };
1271 
1272 /*
1273 ** Each node of an expression in the parse tree is an instance
1274 ** of this structure.
1275 **
1276 ** Expr.op is the opcode.  The integer parser token codes are reused
1277 ** as opcodes here.  For example, the parser defines TK_GE to be an integer
1278 ** code representing the ">=" operator.  This same integer code is reused
1279 ** to represent the greater-than-or-equal-to operator in the expression
1280 ** tree.
1281 **
1282 ** Expr.pRight and Expr.pLeft are subexpressions.  Expr.pList is a list
1283 ** of argument if the expression is a function.
1284 **
1285 ** Expr.token is the operator token for this node.  For some expressions
1286 ** that have subexpressions, Expr.token can be the complete text that gave
1287 ** rise to the Expr.  In the latter case, the token is marked as being
1288 ** a compound token.
1289 **
1290 ** An expression of the form ID or ID.ID refers to a column in a table.
1291 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
1292 ** the integer cursor number of a VDBE cursor pointing to that table and
1293 ** Expr.iColumn is the column number for the specific column.  If the
1294 ** expression is used as a result in an aggregate SELECT, then the
1295 ** value is also stored in the Expr.iAgg column in the aggregate so that
1296 ** it can be accessed after all aggregates are computed.
1297 **
1298 ** If the expression is a function, the Expr.iTable is an integer code
1299 ** representing which function.  If the expression is an unbound variable
1300 ** marker (a question mark character '?' in the original SQL) then the
1301 ** Expr.iTable holds the index number for that variable.
1302 **
1303 ** If the expression is a subquery then Expr.iColumn holds an integer
1304 ** register number containing the result of the subquery.  If the
1305 ** subquery gives a constant result, then iTable is -1.  If the subquery
1306 ** gives a different answer at different times during statement processing
1307 ** then iTable is the address of a subroutine that computes the subquery.
1308 **
1309 ** The Expr.pSelect field points to a SELECT statement.  The SELECT might
1310 ** be the right operand of an IN operator.  Or, if a scalar SELECT appears
1311 ** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
1312 ** operand.
1313 **
1314 ** If the Expr is of type OP_Column, and the table it is selecting from
1315 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
1316 ** corresponding table definition.
1317 */
1318 struct Expr {
1319   u8 op;                 /* Operation performed by this node */
1320   char affinity;         /* The affinity of the column or 0 if not a column */
1321   u16 flags;             /* Various flags.  See below */
1322   CollSeq *pColl;        /* The collation type of the column or 0 */
1323   Expr *pLeft, *pRight;  /* Left and right subnodes */
1324   ExprList *pList;       /* A list of expressions used as function arguments
1325                          ** or in "<expr> IN (<expr-list)" */
1326   Token token;           /* An operand token */
1327   Token span;            /* Complete text of the expression */
1328   int iTable, iColumn;   /* When op==TK_COLUMN, then this expr node means the
1329                          ** iColumn-th field of the iTable-th table. */
1330   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
1331   int iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
1332   int iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
1333   Select *pSelect;       /* When the expression is a sub-select.  Also the
1334                          ** right side of "<expr> IN (<select>)" */
1335   Table *pTab;           /* Table for TK_COLUMN expressions. */
1336 #if SQLITE_MAX_EXPR_DEPTH>0
1337   int nHeight;           /* Height of the tree headed by this node */
1338 #endif
1339 };
1340 
1341 /*
1342 ** The following are the meanings of bits in the Expr.flags field.
1343 */
1344 #define EP_FromJoin   0x0001  /* Originated in ON or USING clause of a join */
1345 #define EP_Agg        0x0002  /* Contains one or more aggregate functions */
1346 #define EP_Resolved   0x0004  /* IDs have been resolved to COLUMNs */
1347 #define EP_Error      0x0008  /* Expression contains one or more errors */
1348 #define EP_Distinct   0x0010  /* Aggregate function with DISTINCT keyword */
1349 #define EP_VarSelect  0x0020  /* pSelect is correlated, not constant */
1350 #define EP_Dequoted   0x0040  /* True if the string has been dequoted */
1351 #define EP_InfixFunc  0x0080  /* True for an infix function: LIKE, GLOB, etc */
1352 #define EP_ExpCollate 0x0100  /* Collating sequence specified explicitly */
1353 #define EP_AnyAff     0x0200  /* Can take a cached column of any affinity */
1354 #define EP_FixedDest  0x0400  /* Result needed in a specific register */
1355 #define EP_IntValue   0x0800  /* Integer value contained in iTable */
1356 /*
1357 ** These macros can be used to test, set, or clear bits in the
1358 ** Expr.flags field.
1359 */
1360 #define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
1361 #define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
1362 #define ExprSetProperty(E,P)     (E)->flags|=(P)
1363 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
1364 
1365 /*
1366 ** A list of expressions.  Each expression may optionally have a
1367 ** name.  An expr/name combination can be used in several ways, such
1368 ** as the list of "expr AS ID" fields following a "SELECT" or in the
1369 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
1370 ** also be used as the argument to a function, in which case the a.zName
1371 ** field is not used.
1372 */
1373 struct ExprList {
1374   int nExpr;             /* Number of expressions on the list */
1375   int nAlloc;            /* Number of entries allocated below */
1376   int iECursor;          /* VDBE Cursor associated with this ExprList */
1377   struct ExprList_item {
1378     Expr *pExpr;           /* The list of expressions */
1379     char *zName;           /* Token associated with this expression */
1380     u8 sortOrder;          /* 1 for DESC or 0 for ASC */
1381     u8 done;               /* A flag to indicate when processing is finished */
1382     u16 iCol;              /* For ORDER BY, column number in result set */
1383     u16 iAlias;            /* Index into Parse.aAlias[] for zName */
1384   } *a;                  /* One entry for each expression */
1385 };
1386 
1387 /*
1388 ** An instance of this structure can hold a simple list of identifiers,
1389 ** such as the list "a,b,c" in the following statements:
1390 **
1391 **      INSERT INTO t(a,b,c) VALUES ...;
1392 **      CREATE INDEX idx ON t(a,b,c);
1393 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
1394 **
1395 ** The IdList.a.idx field is used when the IdList represents the list of
1396 ** column names after a table name in an INSERT statement.  In the statement
1397 **
1398 **     INSERT INTO t(a,b,c) ...
1399 **
1400 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
1401 */
1402 struct IdList {
1403   struct IdList_item {
1404     char *zName;      /* Name of the identifier */
1405     int idx;          /* Index in some Table.aCol[] of a column named zName */
1406   } *a;
1407   int nId;         /* Number of identifiers on the list */
1408   int nAlloc;      /* Number of entries allocated for a[] below */
1409 };
1410 
1411 /*
1412 ** The bitmask datatype defined below is used for various optimizations.
1413 **
1414 ** Changing this from a 64-bit to a 32-bit type limits the number of
1415 ** tables in a join to 32 instead of 64.  But it also reduces the size
1416 ** of the library by 738 bytes on ix86.
1417 */
1418 typedef u64 Bitmask;
1419 
1420 /*
1421 ** The following structure describes the FROM clause of a SELECT statement.
1422 ** Each table or subquery in the FROM clause is a separate element of
1423 ** the SrcList.a[] array.
1424 **
1425 ** With the addition of multiple database support, the following structure
1426 ** can also be used to describe a particular table such as the table that
1427 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
1428 ** such a table must be a simple name: ID.  But in SQLite, the table can
1429 ** now be identified by a database name, a dot, then the table name: ID.ID.
1430 **
1431 ** The jointype starts out showing the join type between the current table
1432 ** and the next table on the list.  The parser builds the list this way.
1433 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
1434 ** jointype expresses the join between the table and the previous table.
1435 */
1436 struct SrcList {
1437   i16 nSrc;        /* Number of tables or subqueries in the FROM clause */
1438   i16 nAlloc;      /* Number of entries allocated in a[] below */
1439   struct SrcList_item {
1440     char *zDatabase;  /* Name of database holding this table */
1441     char *zName;      /* Name of the table */
1442     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
1443     Table *pTab;      /* An SQL table corresponding to zName */
1444     Select *pSelect;  /* A SELECT statement used in place of a table name */
1445     u8 isPopulated;   /* Temporary table associated with SELECT is populated */
1446     u8 jointype;      /* Type of join between this able and the previous */
1447     int iCursor;      /* The VDBE cursor number used to access this table */
1448     Expr *pOn;        /* The ON clause of a join */
1449     IdList *pUsing;   /* The USING clause of a join */
1450     Bitmask colUsed;  /* Bit N (1<<N) set if column N or pTab is used */
1451   } a[1];             /* One entry for each identifier on the list */
1452 };
1453 
1454 /*
1455 ** Permitted values of the SrcList.a.jointype field
1456 */
1457 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
1458 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
1459 #define JT_NATURAL   0x0004    /* True for a "natural" join */
1460 #define JT_LEFT      0x0008    /* Left outer join */
1461 #define JT_RIGHT     0x0010    /* Right outer join */
1462 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
1463 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
1464 
1465 /*
1466 ** For each nested loop in a WHERE clause implementation, the WhereInfo
1467 ** structure contains a single instance of this structure.  This structure
1468 ** is intended to be private the the where.c module and should not be
1469 ** access or modified by other modules.
1470 **
1471 ** The pIdxInfo and pBestIdx fields are used to help pick the best
1472 ** index on a virtual table.  The pIdxInfo pointer contains indexing
1473 ** information for the i-th table in the FROM clause before reordering.
1474 ** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
1475 ** The pBestIdx pointer is a copy of pIdxInfo for the i-th table after
1476 ** FROM clause ordering.  This is a little confusing so I will repeat
1477 ** it in different words.  WhereInfo.a[i].pIdxInfo is index information
1478 ** for WhereInfo.pTabList.a[i].  WhereInfo.a[i].pBestInfo is the
1479 ** index information for the i-th loop of the join.  pBestInfo is always
1480 ** either NULL or a copy of some pIdxInfo.  So for cleanup it is
1481 ** sufficient to free all of the pIdxInfo pointers.
1482 **
1483 */
1484 struct WhereLevel {
1485   int iFrom;            /* Which entry in the FROM clause */
1486   int flags;            /* Flags associated with this level */
1487   int iMem;             /* First memory cell used by this level */
1488   int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
1489   Index *pIdx;          /* Index used.  NULL if no index */
1490   int iTabCur;          /* The VDBE cursor used to access the table */
1491   int iIdxCur;          /* The VDBE cursor used to acesss pIdx */
1492   int brk;              /* Jump here to break out of the loop */
1493   int nxt;              /* Jump here to start the next IN combination */
1494   int cont;             /* Jump here to continue with the next loop cycle */
1495   int top;              /* First instruction of interior of the loop */
1496   int op, p1, p2;       /* Opcode used to terminate the loop */
1497   int nEq;              /* Number of == or IN constraints on this loop */
1498   int nIn;              /* Number of IN operators constraining this loop */
1499   struct InLoop {
1500     int iCur;              /* The VDBE cursor used by this IN operator */
1501     int topAddr;           /* Top of the IN loop */
1502   } *aInLoop;           /* Information about each nested IN operator */
1503   sqlite3_index_info *pBestIdx;  /* Index information for this level */
1504 
1505   /* The following field is really not part of the current level.  But
1506   ** we need a place to cache index information for each table in the
1507   ** FROM clause and the WhereLevel structure is a convenient place.
1508   */
1509   sqlite3_index_info *pIdxInfo;  /* Index info for n-th source table */
1510 };
1511 
1512 /*
1513 ** Flags appropriate for the wflags parameter of sqlite3WhereBegin().
1514 */
1515 #define WHERE_ORDERBY_NORMAL     0   /* No-op */
1516 #define WHERE_ORDERBY_MIN        1   /* ORDER BY processing for min() func */
1517 #define WHERE_ORDERBY_MAX        2   /* ORDER BY processing for max() func */
1518 #define WHERE_ONEPASS_DESIRED    4   /* Want to do one-pass UPDATE/DELETE */
1519 
1520 /*
1521 ** The WHERE clause processing routine has two halves.  The
1522 ** first part does the start of the WHERE loop and the second
1523 ** half does the tail of the WHERE loop.  An instance of
1524 ** this structure is returned by the first half and passed
1525 ** into the second half to give some continuity.
1526 */
1527 struct WhereInfo {
1528   Parse *pParse;       /* Parsing and code generating context */
1529   u8 okOnePass;        /* Ok to use one-pass algorithm for UPDATE or DELETE */
1530   SrcList *pTabList;   /* List of tables in the join */
1531   int iTop;            /* The very beginning of the WHERE loop */
1532   int iContinue;       /* Jump here to continue with next record */
1533   int iBreak;          /* Jump here to break out of the loop */
1534   int nLevel;          /* Number of nested loop */
1535   sqlite3_index_info **apInfo;  /* Array of pointers to index info structures */
1536   WhereLevel a[1];     /* Information about each nest loop in the WHERE */
1537 };
1538 
1539 /*
1540 ** A NameContext defines a context in which to resolve table and column
1541 ** names.  The context consists of a list of tables (the pSrcList) field and
1542 ** a list of named expression (pEList).  The named expression list may
1543 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
1544 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
1545 ** pEList corresponds to the result set of a SELECT and is NULL for
1546 ** other statements.
1547 **
1548 ** NameContexts can be nested.  When resolving names, the inner-most
1549 ** context is searched first.  If no match is found, the next outer
1550 ** context is checked.  If there is still no match, the next context
1551 ** is checked.  This process continues until either a match is found
1552 ** or all contexts are check.  When a match is found, the nRef member of
1553 ** the context containing the match is incremented.
1554 **
1555 ** Each subquery gets a new NameContext.  The pNext field points to the
1556 ** NameContext in the parent query.  Thus the process of scanning the
1557 ** NameContext list corresponds to searching through successively outer
1558 ** subqueries looking for a match.
1559 */
1560 struct NameContext {
1561   Parse *pParse;       /* The parser */
1562   SrcList *pSrcList;   /* One or more tables used to resolve names */
1563   ExprList *pEList;    /* Optional list of named expressions */
1564   int nRef;            /* Number of names resolved by this context */
1565   int nErr;            /* Number of errors encountered while resolving names */
1566   u8 allowAgg;         /* Aggregate functions allowed here */
1567   u8 hasAgg;           /* True if aggregates are seen */
1568   u8 isCheck;          /* True if resolving names in a CHECK constraint */
1569   int nDepth;          /* Depth of subquery recursion. 1 for no recursion */
1570   AggInfo *pAggInfo;   /* Information about aggregates at this level */
1571   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
1572 };
1573 
1574 /*
1575 ** An instance of the following structure contains all information
1576 ** needed to generate code for a single SELECT statement.
1577 **
1578 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
1579 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
1580 ** limit and nOffset to the value of the offset (or 0 if there is not
1581 ** offset).  But later on, nLimit and nOffset become the memory locations
1582 ** in the VDBE that record the limit and offset counters.
1583 **
1584 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
1585 ** These addresses must be stored so that we can go back and fill in
1586 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
1587 ** the number of columns in P2 can be computed at the same time
1588 ** as the OP_OpenEphm instruction is coded because not
1589 ** enough information about the compound query is known at that point.
1590 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
1591 ** for the result set.  The KeyInfo for addrOpenTran[2] contains collating
1592 ** sequences for the ORDER BY clause.
1593 */
1594 struct Select {
1595   ExprList *pEList;      /* The fields of the result */
1596   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
1597   char affinity;         /* MakeRecord with this affinity for SRT_Set */
1598   u16 selFlags;          /* Various SF_* values */
1599   SrcList *pSrc;         /* The FROM clause */
1600   Expr *pWhere;          /* The WHERE clause */
1601   ExprList *pGroupBy;    /* The GROUP BY clause */
1602   Expr *pHaving;         /* The HAVING clause */
1603   ExprList *pOrderBy;    /* The ORDER BY clause */
1604   Select *pPrior;        /* Prior select in a compound select statement */
1605   Select *pNext;         /* Next select to the left in a compound */
1606   Select *pRightmost;    /* Right-most select in a compound select statement */
1607   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
1608   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
1609   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
1610   int addrOpenEphm[3];   /* OP_OpenEphem opcodes related to this select */
1611 };
1612 
1613 /*
1614 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
1615 ** "Select Flag".
1616 */
1617 #define SF_Distinct        0x0001  /* Output should be DISTINCT */
1618 #define SF_Resolved        0x0002  /* Identifiers have been resolved */
1619 #define SF_Aggregate       0x0004  /* Contains aggregate functions */
1620 #define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
1621 #define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
1622 #define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
1623 
1624 
1625 /*
1626 ** The results of a select can be distributed in several ways.  The
1627 ** "SRT" prefix means "SELECT Result Type".
1628 */
1629 #define SRT_Union        1  /* Store result as keys in an index */
1630 #define SRT_Except       2  /* Remove result from a UNION index */
1631 #define SRT_Exists       3  /* Store 1 if the result is not empty */
1632 #define SRT_Discard      4  /* Do not save the results anywhere */
1633 
1634 /* The ORDER BY clause is ignored for all of the above */
1635 #define IgnorableOrderby(X) ((X->eDest)<=SRT_Discard)
1636 
1637 #define SRT_Output       5  /* Output each row of result */
1638 #define SRT_Mem          6  /* Store result in a memory cell */
1639 #define SRT_Set          7  /* Store results as keys in an index */
1640 #define SRT_Table        8  /* Store result as data with an automatic rowid */
1641 #define SRT_EphemTab     9  /* Create transient tab and store like SRT_Table */
1642 #define SRT_Coroutine   10  /* Generate a single row of result */
1643 
1644 /*
1645 ** A structure used to customize the behaviour of sqlite3Select(). See
1646 ** comments above sqlite3Select() for details.
1647 */
1648 typedef struct SelectDest SelectDest;
1649 struct SelectDest {
1650   u8 eDest;         /* How to dispose of the results */
1651   u8 affinity;      /* Affinity used when eDest==SRT_Set */
1652   int iParm;        /* A parameter used by the eDest disposal method */
1653   int iMem;         /* Base register where results are written */
1654   int nMem;         /* Number of registers allocated */
1655 };
1656 
1657 /*
1658 ** An SQL parser context.  A copy of this structure is passed through
1659 ** the parser and down into all the parser action routine in order to
1660 ** carry around information that is global to the entire parse.
1661 **
1662 ** The structure is divided into two parts.  When the parser and code
1663 ** generate call themselves recursively, the first part of the structure
1664 ** is constant but the second part is reset at the beginning and end of
1665 ** each recursion.
1666 **
1667 ** The nTableLock and aTableLock variables are only used if the shared-cache
1668 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
1669 ** used to store the set of table-locks required by the statement being
1670 ** compiled. Function sqlite3TableLock() is used to add entries to the
1671 ** list.
1672 */
1673 struct Parse {
1674   sqlite3 *db;         /* The main database structure */
1675   int rc;              /* Return code from execution */
1676   char *zErrMsg;       /* An error message */
1677   Vdbe *pVdbe;         /* An engine for executing database bytecode */
1678   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
1679   u8 nameClash;        /* A permanent table name clashes with temp table name */
1680   u8 checkSchema;      /* Causes schema cookie check after an error */
1681   u8 nested;           /* Number of nested calls to the parser/code generator */
1682   u8 parseError;       /* True after a parsing error.  Ticket #1794 */
1683   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
1684   u8 nTempInUse;       /* Number of aTempReg[] currently checked out */
1685   int aTempReg[8];     /* Holding area for temporary registers */
1686   int nRangeReg;       /* Size of the temporary register block */
1687   int iRangeReg;       /* First register in temporary register block */
1688   int nErr;            /* Number of errors seen */
1689   int nTab;            /* Number of previously allocated VDBE cursors */
1690   int nMem;            /* Number of memory cells used so far */
1691   int nSet;            /* Number of sets used so far */
1692   int ckBase;          /* Base register of data during check constraints */
1693   int disableColCache; /* True to disable adding to column cache */
1694   int nColCache;       /* Number of entries in the column cache */
1695   int iColCache;       /* Next entry of the cache to replace */
1696   struct yColCache {
1697     int iTable;           /* Table cursor number */
1698     int iColumn;          /* Table column number */
1699     char affChange;       /* True if this register has had an affinity change */
1700     int iReg;             /* Register holding value of this column */
1701   } aColCache[10];     /* One for each valid column cache entry */
1702   u32 writeMask;       /* Start a write transaction on these databases */
1703   u32 cookieMask;      /* Bitmask of schema verified databases */
1704   int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
1705   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
1706 #ifndef SQLITE_OMIT_SHARED_CACHE
1707   int nTableLock;        /* Number of locks in aTableLock */
1708   TableLock *aTableLock; /* Required table locks for shared-cache mode */
1709 #endif
1710   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
1711   int regRoot;         /* Register holding root page number for new objects */
1712 
1713   /* Above is constant between recursions.  Below is reset before and after
1714   ** each recursion */
1715 
1716   int nVar;            /* Number of '?' variables seen in the SQL so far */
1717   int nVarExpr;        /* Number of used slots in apVarExpr[] */
1718   int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
1719   Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
1720   int nAlias;          /* Number of aliased result set columns */
1721   int *aAlias;         /* Register used to hold aliased result */
1722   u8 explain;          /* True if the EXPLAIN flag is found on the query */
1723   Token sErrToken;     /* The token at which the error occurred */
1724   Token sNameToken;    /* Token with unqualified schema object name */
1725   Token sLastToken;    /* The last token parsed */
1726   const char *zSql;    /* All SQL text */
1727   const char *zTail;   /* All SQL text past the last semicolon parsed */
1728   Table *pNewTable;    /* A table being constructed by CREATE TABLE */
1729   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
1730   TriggerStack *trigStack;  /* Trigger actions being coded */
1731   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
1732 #ifndef SQLITE_OMIT_VIRTUALTABLE
1733   Token sArg;                /* Complete text of a module argument */
1734   u8 declareVtab;            /* True if inside sqlite3_declare_vtab() */
1735   int nVtabLock;             /* Number of virtual tables to lock */
1736   Table **apVtabLock;        /* Pointer to virtual tables needing locking */
1737 #endif
1738   int nHeight;            /* Expression tree height of current sub-select */
1739   Table *pZombieTab;      /* List of Table objects to delete after code gen */
1740 };
1741 
1742 #ifdef SQLITE_OMIT_VIRTUALTABLE
1743   #define IN_DECLARE_VTAB 0
1744 #else
1745   #define IN_DECLARE_VTAB (pParse->declareVtab)
1746 #endif
1747 
1748 /*
1749 ** An instance of the following structure can be declared on a stack and used
1750 ** to save the Parse.zAuthContext value so that it can be restored later.
1751 */
1752 struct AuthContext {
1753   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
1754   Parse *pParse;              /* The Parse structure */
1755 };
1756 
1757 /*
1758 ** Bitfield flags for P2 value in OP_Insert and OP_Delete
1759 */
1760 #define OPFLAG_NCHANGE   1    /* Set to update db->nChange */
1761 #define OPFLAG_LASTROWID 2    /* Set to update db->lastRowid */
1762 #define OPFLAG_ISUPDATE  4    /* This OP_Insert is an sql UPDATE */
1763 #define OPFLAG_APPEND    8    /* This is likely to be an append */
1764 
1765 /*
1766  * Each trigger present in the database schema is stored as an instance of
1767  * struct Trigger.
1768  *
1769  * Pointers to instances of struct Trigger are stored in two ways.
1770  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
1771  *    database). This allows Trigger structures to be retrieved by name.
1772  * 2. All triggers associated with a single table form a linked list, using the
1773  *    pNext member of struct Trigger. A pointer to the first element of the
1774  *    linked list is stored as the "pTrigger" member of the associated
1775  *    struct Table.
1776  *
1777  * The "step_list" member points to the first element of a linked list
1778  * containing the SQL statements specified as the trigger program.
1779  */
1780 struct Trigger {
1781   char *name;             /* The name of the trigger                        */
1782   char *table;            /* The table or view to which the trigger applies */
1783   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
1784   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
1785   Expr *pWhen;            /* The WHEN clause of the expresion (may be NULL) */
1786   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
1787                              the <column-list> is stored here */
1788   Token nameToken;        /* Token containing zName. Use during parsing only */
1789   Schema *pSchema;        /* Schema containing the trigger */
1790   Schema *pTabSchema;     /* Schema containing the table */
1791   TriggerStep *step_list; /* Link list of trigger program steps             */
1792   Trigger *pNext;         /* Next trigger associated with the table */
1793 };
1794 
1795 /*
1796 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
1797 ** determine which.
1798 **
1799 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
1800 ** In that cases, the constants below can be ORed together.
1801 */
1802 #define TRIGGER_BEFORE  1
1803 #define TRIGGER_AFTER   2
1804 
1805 /*
1806  * An instance of struct TriggerStep is used to store a single SQL statement
1807  * that is a part of a trigger-program.
1808  *
1809  * Instances of struct TriggerStep are stored in a singly linked list (linked
1810  * using the "pNext" member) referenced by the "step_list" member of the
1811  * associated struct Trigger instance. The first element of the linked list is
1812  * the first step of the trigger-program.
1813  *
1814  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
1815  * "SELECT" statement. The meanings of the other members is determined by the
1816  * value of "op" as follows:
1817  *
1818  * (op == TK_INSERT)
1819  * orconf    -> stores the ON CONFLICT algorithm
1820  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
1821  *              this stores a pointer to the SELECT statement. Otherwise NULL.
1822  * target    -> A token holding the name of the table to insert into.
1823  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
1824  *              this stores values to be inserted. Otherwise NULL.
1825  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
1826  *              statement, then this stores the column-names to be
1827  *              inserted into.
1828  *
1829  * (op == TK_DELETE)
1830  * target    -> A token holding the name of the table to delete from.
1831  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
1832  *              Otherwise NULL.
1833  *
1834  * (op == TK_UPDATE)
1835  * target    -> A token holding the name of the table to update rows of.
1836  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
1837  *              Otherwise NULL.
1838  * pExprList -> A list of the columns to update and the expressions to update
1839  *              them to. See sqlite3Update() documentation of "pChanges"
1840  *              argument.
1841  *
1842  */
1843 struct TriggerStep {
1844   int op;              /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
1845   int orconf;          /* OE_Rollback etc. */
1846   Trigger *pTrig;      /* The trigger that this step is a part of */
1847 
1848   Select *pSelect;     /* Valid for SELECT and sometimes
1849                           INSERT steps (when pExprList == 0) */
1850   Token target;        /* Valid for DELETE, UPDATE, INSERT steps */
1851   Expr *pWhere;        /* Valid for DELETE, UPDATE steps */
1852   ExprList *pExprList; /* Valid for UPDATE statements and sometimes
1853                            INSERT steps (when pSelect == 0)         */
1854   IdList *pIdList;     /* Valid for INSERT statements only */
1855   TriggerStep *pNext;  /* Next in the link-list */
1856   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
1857 };
1858 
1859 /*
1860  * An instance of struct TriggerStack stores information required during code
1861  * generation of a single trigger program. While the trigger program is being
1862  * coded, its associated TriggerStack instance is pointed to by the
1863  * "pTriggerStack" member of the Parse structure.
1864  *
1865  * The pTab member points to the table that triggers are being coded on. The
1866  * newIdx member contains the index of the vdbe cursor that points at the temp
1867  * table that stores the new.* references. If new.* references are not valid
1868  * for the trigger being coded (for example an ON DELETE trigger), then newIdx
1869  * is set to -1. The oldIdx member is analogous to newIdx, for old.* references.
1870  *
1871  * The ON CONFLICT policy to be used for the trigger program steps is stored
1872  * as the orconf member. If this is OE_Default, then the ON CONFLICT clause
1873  * specified for individual triggers steps is used.
1874  *
1875  * struct TriggerStack has a "pNext" member, to allow linked lists to be
1876  * constructed. When coding nested triggers (triggers fired by other triggers)
1877  * each nested trigger stores its parent trigger's TriggerStack as the "pNext"
1878  * pointer. Once the nested trigger has been coded, the pNext value is restored
1879  * to the pTriggerStack member of the Parse stucture and coding of the parent
1880  * trigger continues.
1881  *
1882  * Before a nested trigger is coded, the linked list pointed to by the
1883  * pTriggerStack is scanned to ensure that the trigger is not about to be coded
1884  * recursively. If this condition is detected, the nested trigger is not coded.
1885  */
1886 struct TriggerStack {
1887   Table *pTab;         /* Table that triggers are currently being coded on */
1888   int newIdx;          /* Index of vdbe cursor to "new" temp table */
1889   int oldIdx;          /* Index of vdbe cursor to "old" temp table */
1890   u32 newColMask;
1891   u32 oldColMask;
1892   int orconf;          /* Current orconf policy */
1893   int ignoreJump;      /* where to jump to for a RAISE(IGNORE) */
1894   Trigger *pTrigger;   /* The trigger currently being coded */
1895   TriggerStack *pNext; /* Next trigger down on the trigger stack */
1896 };
1897 
1898 /*
1899 ** The following structure contains information used by the sqliteFix...
1900 ** routines as they walk the parse tree to make database references
1901 ** explicit.
1902 */
1903 typedef struct DbFixer DbFixer;
1904 struct DbFixer {
1905   Parse *pParse;      /* The parsing context.  Error messages written here */
1906   const char *zDb;    /* Make sure all objects are contained in this database */
1907   const char *zType;  /* Type of the container - used for error messages */
1908   const Token *pName; /* Name of the container - used for error messages */
1909 };
1910 
1911 /*
1912 ** An objected used to accumulate the text of a string where we
1913 ** do not necessarily know how big the string will be in the end.
1914 */
1915 struct StrAccum {
1916   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
1917   char *zBase;         /* A base allocation.  Not from malloc. */
1918   char *zText;         /* The string collected so far */
1919   int  nChar;          /* Length of the string so far */
1920   int  nAlloc;         /* Amount of space allocated in zText */
1921   int  mxAlloc;        /* Maximum allowed string length */
1922   u8   mallocFailed;   /* Becomes true if any memory allocation fails */
1923   u8   useMalloc;      /* True if zText is enlargable using realloc */
1924   u8   tooBig;         /* Becomes true if string size exceeds limits */
1925 };
1926 
1927 /*
1928 ** A pointer to this structure is used to communicate information
1929 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
1930 */
1931 typedef struct {
1932   sqlite3 *db;        /* The database being initialized */
1933   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
1934   char **pzErrMsg;    /* Error message stored here */
1935   int rc;             /* Result code stored here */
1936 } InitData;
1937 
1938 /*
1939 ** Structure containing global configuration data for the SQLite library.
1940 **
1941 ** This structure also contains some state information.
1942 */
1943 struct Sqlite3Config {
1944   int bMemstat;                     /* True to enable memory status */
1945   int bCoreMutex;                   /* True to enable core mutexing */
1946   int bFullMutex;                   /* True to enable full mutexing */
1947   int mxStrlen;                     /* Maximum string length */
1948   int szLookaside;                  /* Default lookaside buffer size */
1949   int nLookaside;                   /* Default lookaside buffer count */
1950   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
1951   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
1952   void *pHeap;                      /* Heap storage space */
1953   int nHeap;                        /* Size of pHeap[] */
1954   int mnReq, mxReq;                 /* Min and max heap requests sizes */
1955   void *pScratch;                   /* Scratch memory */
1956   int szScratch;                    /* Size of each scratch buffer */
1957   int nScratch;                     /* Number of scratch buffers */
1958   void *pPage;                      /* Page cache memory */
1959   int szPage;                       /* Size of each page in pPage[] */
1960   int nPage;                        /* Number of pages in pPage[] */
1961   int isInit;                       /* True after initialization has finished */
1962   int inProgress;                   /* True while initialization in progress */
1963   int isMallocInit;                 /* True after malloc is initialized */
1964   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
1965   int nRefInitMutex;                /* Number of users of pInitMutex */
1966   int nSmall;                       /* alloc size threshold used by mem6.c */
1967   int mxParserStack;                /* maximum depth of the parser stack */
1968   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
1969 };
1970 
1971 /*
1972 ** Context pointer passed down through the tree-walk.
1973 */
1974 struct Walker {
1975   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
1976   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
1977   Parse *pParse;                            /* Parser context.  */
1978   union {                                   /* Extra data for callback */
1979     NameContext *pNC;                          /* Naming context */
1980     int i;                                     /* Integer value */
1981   } u;
1982 };
1983 
1984 /* Forward declarations */
1985 int sqlite3WalkExpr(Walker*, Expr*);
1986 int sqlite3WalkExprList(Walker*, ExprList*);
1987 int sqlite3WalkSelect(Walker*, Select*);
1988 int sqlite3WalkSelectExpr(Walker*, Select*);
1989 int sqlite3WalkSelectFrom(Walker*, Select*);
1990 
1991 /*
1992 ** Return code from the parse-tree walking primitives and their
1993 ** callbacks.
1994 */
1995 #define WRC_Continue    0
1996 #define WRC_Prune       1
1997 #define WRC_Abort       2
1998 
1999 /*
2000 ** Assuming zIn points to the first byte of a UTF-8 character,
2001 ** advance zIn to point to the first byte of the next UTF-8 character.
2002 */
2003 #define SQLITE_SKIP_UTF8(zIn) {                        \
2004   if( (*(zIn++))>=0xc0 ){                              \
2005     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
2006   }                                                    \
2007 }
2008 
2009 /*
2010 ** The SQLITE_CORRUPT_BKPT macro can be either a constant (for production
2011 ** builds) or a function call (for debugging).  If it is a function call,
2012 ** it allows the operator to set a breakpoint at the spot where database
2013 ** corruption is first detected.
2014 */
2015 #ifdef SQLITE_DEBUG
2016   int sqlite3Corrupt(void);
2017 # define SQLITE_CORRUPT_BKPT sqlite3Corrupt()
2018 #else
2019 # define SQLITE_CORRUPT_BKPT SQLITE_CORRUPT
2020 #endif
2021 
2022 /*
2023 ** Internal function prototypes
2024 */
2025 int sqlite3StrICmp(const char *, const char *);
2026 int sqlite3StrNICmp(const char *, const char *, int);
2027 int sqlite3IsNumber(const char*, int*, u8);
2028 int sqlite3Strlen(sqlite3*, const char*);
2029 
2030 int sqlite3MallocInit(void);
2031 void sqlite3MallocEnd(void);
2032 void *sqlite3Malloc(int);
2033 void *sqlite3MallocZero(int);
2034 void *sqlite3DbMallocZero(sqlite3*, int);
2035 void *sqlite3DbMallocRaw(sqlite3*, int);
2036 char *sqlite3DbStrDup(sqlite3*,const char*);
2037 char *sqlite3DbStrNDup(sqlite3*,const char*, int);
2038 void *sqlite3Realloc(void*, int);
2039 void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
2040 void *sqlite3DbRealloc(sqlite3 *, void *, int);
2041 void sqlite3DbFree(sqlite3*, void*);
2042 int sqlite3MallocSize(void*);
2043 int sqlite3DbMallocSize(sqlite3*, void*);
2044 void *sqlite3ScratchMalloc(int);
2045 void sqlite3ScratchFree(void*);
2046 void *sqlite3PageMalloc(int);
2047 void sqlite3PageFree(void*);
2048 void sqlite3MemSetDefault(void);
2049 const sqlite3_mem_methods *sqlite3MemGetDefault(void);
2050 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
2051 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
2052 const sqlite3_mem_methods *sqlite3MemGetMemsys6(void);
2053 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
2054 int sqlite3MemoryAlarm(void (*)(void*, sqlite3_int64, int), void*, sqlite3_int64);
2055 
2056 #ifndef SQLITE_MUTEX_NOOP
2057   sqlite3_mutex_methods *sqlite3DefaultMutex(void);
2058   sqlite3_mutex *sqlite3MutexAlloc(int);
2059   int sqlite3MutexInit(void);
2060   int sqlite3MutexEnd(void);
2061 #endif
2062 
2063 int sqlite3StatusValue(int);
2064 void sqlite3StatusAdd(int, int);
2065 void sqlite3StatusSet(int, int);
2066 
2067 int sqlite3IsNaN(double);
2068 
2069 void sqlite3VXPrintf(StrAccum*, int, const char*, va_list);
2070 char *sqlite3MPrintf(sqlite3*,const char*, ...);
2071 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
2072 char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
2073 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
2074   void sqlite3DebugPrintf(const char*, ...);
2075 #endif
2076 #if defined(SQLITE_TEST)
2077   void *sqlite3TestTextToPtr(const char*);
2078 #endif
2079 void sqlite3SetString(char **, sqlite3*, const char*, ...);
2080 void sqlite3ErrorMsg(Parse*, const char*, ...);
2081 void sqlite3ErrorClear(Parse*);
2082 void sqlite3Dequote(char*);
2083 void sqlite3DequoteExpr(sqlite3*, Expr*);
2084 int sqlite3KeywordCode(const unsigned char*, int);
2085 int sqlite3RunParser(Parse*, const char*, char **);
2086 void sqlite3FinishCoding(Parse*);
2087 int sqlite3GetTempReg(Parse*);
2088 void sqlite3ReleaseTempReg(Parse*,int);
2089 int sqlite3GetTempRange(Parse*,int);
2090 void sqlite3ReleaseTempRange(Parse*,int,int);
2091 Expr *sqlite3Expr(sqlite3*, int, Expr*, Expr*, const Token*);
2092 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
2093 Expr *sqlite3RegisterExpr(Parse*,Token*);
2094 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
2095 void sqlite3ExprSpan(Expr*,Token*,Token*);
2096 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
2097 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
2098 void sqlite3ExprDelete(sqlite3*, Expr*);
2099 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*,Token*);
2100 void sqlite3ExprListDelete(sqlite3*, ExprList*);
2101 int sqlite3Init(sqlite3*, char**);
2102 int sqlite3InitCallback(void*, int, char**, char**);
2103 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
2104 void sqlite3ResetInternalSchema(sqlite3*, int);
2105 void sqlite3BeginParse(Parse*,int);
2106 void sqlite3CommitInternalChanges(sqlite3*);
2107 Table *sqlite3ResultSetOfSelect(Parse*,Select*);
2108 void sqlite3OpenMasterTable(Parse *, int);
2109 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
2110 void sqlite3AddColumn(Parse*,Token*);
2111 void sqlite3AddNotNull(Parse*, int);
2112 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
2113 void sqlite3AddCheckConstraint(Parse*, Expr*);
2114 void sqlite3AddColumnType(Parse*,Token*);
2115 void sqlite3AddDefaultValue(Parse*,Expr*);
2116 void sqlite3AddCollateType(Parse*, Token*);
2117 void sqlite3EndTable(Parse*,Token*,Token*,Select*);
2118 
2119 Bitvec *sqlite3BitvecCreate(u32);
2120 int sqlite3BitvecTest(Bitvec*, u32);
2121 int sqlite3BitvecSet(Bitvec*, u32);
2122 void sqlite3BitvecClear(Bitvec*, u32);
2123 void sqlite3BitvecDestroy(Bitvec*);
2124 int sqlite3BitvecBuiltinTest(int,int*);
2125 
2126 void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
2127 
2128 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
2129   int sqlite3ViewGetColumnNames(Parse*,Table*);
2130 #else
2131 # define sqlite3ViewGetColumnNames(A,B) 0
2132 #endif
2133 
2134 void sqlite3DropTable(Parse*, SrcList*, int, int);
2135 void sqlite3DeleteTable(Table*);
2136 void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
2137 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int,int*,int*,int*);
2138 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
2139 int sqlite3IdListIndex(IdList*,const char*);
2140 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
2141 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*, Token*,
2142                                       Select*, Expr*, IdList*);
2143 void sqlite3SrcListShiftJoinType(SrcList*);
2144 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
2145 void sqlite3IdListDelete(sqlite3*, IdList*);
2146 void sqlite3SrcListDelete(sqlite3*, SrcList*);
2147 void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
2148                         Token*, int, int);
2149 void sqlite3DropIndex(Parse*, SrcList*, int);
2150 int sqlite3Select(Parse*, Select*, SelectDest*);
2151 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
2152                          Expr*,ExprList*,int,Expr*,Expr*);
2153 void sqlite3SelectDelete(sqlite3*, Select*);
2154 Table *sqlite3SrcListLookup(Parse*, SrcList*);
2155 int sqlite3IsReadOnly(Parse*, Table*, int);
2156 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
2157 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
2158 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
2159 WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**, u8);
2160 void sqlite3WhereEnd(WhereInfo*);
2161 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, int);
2162 void sqlite3ExprCodeMove(Parse*, int, int, int);
2163 void sqlite3ExprCodeCopy(Parse*, int, int, int);
2164 void sqlite3ExprClearColumnCache(Parse*, int);
2165 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
2166 int sqlite3ExprWritableRegister(Parse*,int,int);
2167 void sqlite3ExprHardCopy(Parse*,int,int);
2168 int sqlite3ExprCode(Parse*, Expr*, int);
2169 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
2170 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
2171 int sqlite3ExprCodeAndCache(Parse*, Expr*, int);
2172 void sqlite3ExprCodeConstants(Parse*, Expr*);
2173 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int);
2174 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
2175 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
2176 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
2177 Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
2178 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
2179 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
2180 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
2181 void sqlite3Vacuum(Parse*);
2182 int sqlite3RunVacuum(char**, sqlite3*);
2183 char *sqlite3NameFromToken(sqlite3*, Token*);
2184 int sqlite3ExprCompare(Expr*, Expr*);
2185 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
2186 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
2187 Vdbe *sqlite3GetVdbe(Parse*);
2188 Expr *sqlite3CreateIdExpr(Parse *, const char*);
2189 void sqlite3PrngSaveState(void);
2190 void sqlite3PrngRestoreState(void);
2191 void sqlite3PrngResetState(void);
2192 void sqlite3RollbackAll(sqlite3*);
2193 void sqlite3CodeVerifySchema(Parse*, int);
2194 void sqlite3BeginTransaction(Parse*, int);
2195 void sqlite3CommitTransaction(Parse*);
2196 void sqlite3RollbackTransaction(Parse*);
2197 int sqlite3ExprIsConstant(Expr*);
2198 int sqlite3ExprIsConstantNotJoin(Expr*);
2199 int sqlite3ExprIsConstantOrFunction(Expr*);
2200 int sqlite3ExprIsInteger(Expr*, int*);
2201 int sqlite3IsRowid(const char*);
2202 void sqlite3GenerateRowDelete(Parse*, Table*, int, int, int);
2203 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int*);
2204 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int);
2205 void sqlite3GenerateConstraintChecks(Parse*,Table*,int,int,
2206                                      int*,int,int,int,int);
2207 void sqlite3CompleteInsertion(Parse*, Table*, int, int, int*,int,int,int,int);
2208 int sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
2209 void sqlite3BeginWriteOperation(Parse*, int, int);
2210 Expr *sqlite3ExprDup(sqlite3*,Expr*);
2211 void sqlite3TokenCopy(sqlite3*,Token*, Token*);
2212 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*);
2213 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*);
2214 IdList *sqlite3IdListDup(sqlite3*,IdList*);
2215 Select *sqlite3SelectDup(sqlite3*,Select*);
2216 void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
2217 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);
2218 void sqlite3RegisterBuiltinFunctions(sqlite3*);
2219 void sqlite3RegisterDateTimeFunctions(void);
2220 void sqlite3RegisterGlobalFunctions(void);
2221 int sqlite3GetBuiltinFunction(const char *, int, FuncDef **);
2222 #ifdef SQLITE_DEBUG
2223   int sqlite3SafetyOn(sqlite3*);
2224   int sqlite3SafetyOff(sqlite3*);
2225 #else
2226 # define sqlite3SafetyOn(A) 0
2227 # define sqlite3SafetyOff(A) 0
2228 #endif
2229 int sqlite3SafetyCheckOk(sqlite3*);
2230 int sqlite3SafetyCheckSickOrOk(sqlite3*);
2231 void sqlite3ChangeCookie(Parse*, int);
2232 
2233 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
2234 void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
2235 #endif
2236 
2237 #ifndef SQLITE_OMIT_TRIGGER
2238   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
2239                            Expr*,int, int);
2240   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
2241   void sqlite3DropTrigger(Parse*, SrcList*, int);
2242   void sqlite3DropTriggerPtr(Parse*, Trigger*);
2243   int sqlite3TriggersExist(Parse*, Table*, int, ExprList*);
2244   int sqlite3CodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int,
2245                            int, int, u32*, u32*);
2246   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
2247   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
2248   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
2249   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
2250                                         ExprList*,Select*,int);
2251   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, int);
2252   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
2253   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
2254   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
2255 #else
2256 # define sqlite3TriggersExist(A,B,C,D,E,F) 0
2257 # define sqlite3DeleteTrigger(A,B)
2258 # define sqlite3DropTriggerPtr(A,B)
2259 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
2260 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I,J,K) 0
2261 #endif
2262 
2263 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
2264 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
2265 void sqlite3DeferForeignKey(Parse*, int);
2266 #ifndef SQLITE_OMIT_AUTHORIZATION
2267   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
2268   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
2269   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
2270   void sqlite3AuthContextPop(AuthContext*);
2271 #else
2272 # define sqlite3AuthRead(a,b,c,d)
2273 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
2274 # define sqlite3AuthContextPush(a,b,c)
2275 # define sqlite3AuthContextPop(a)  ((void)(a))
2276 #endif
2277 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
2278 void sqlite3Detach(Parse*, Expr*);
2279 int sqlite3BtreeFactory(const sqlite3 *db, const char *zFilename,
2280                        int omitJournal, int nCache, int flags, Btree **ppBtree);
2281 int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
2282 int sqlite3FixSrcList(DbFixer*, SrcList*);
2283 int sqlite3FixSelect(DbFixer*, Select*);
2284 int sqlite3FixExpr(DbFixer*, Expr*);
2285 int sqlite3FixExprList(DbFixer*, ExprList*);
2286 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
2287 int sqlite3AtoF(const char *z, double*);
2288 int sqlite3GetInt32(const char *, int*);
2289 int sqlite3FitsIn64Bits(const char *, int);
2290 int sqlite3Utf16ByteLen(const void *pData, int nChar);
2291 int sqlite3Utf8CharLen(const char *pData, int nByte);
2292 int sqlite3Utf8Read(const u8*, const u8*, const u8**);
2293 
2294 /*
2295 ** Routines to read and write variable-length integers.  These used to
2296 ** be defined locally, but now we use the varint routines in the util.c
2297 ** file.  Code should use the MACRO forms below, as the Varint32 versions
2298 ** are coded to assume the single byte case is already handled (which
2299 ** the MACRO form does).
2300 */
2301 int sqlite3PutVarint(unsigned char*, u64);
2302 int sqlite3PutVarint32(unsigned char*, u32);
2303 int sqlite3GetVarint(const unsigned char *, u64 *);
2304 int sqlite3GetVarint32(const unsigned char *, u32 *);
2305 int sqlite3VarintLen(u64 v);
2306 
2307 /*
2308 ** The header of a record consists of a sequence variable-length integers.
2309 ** These integers are almost always small and are encoded as a single byte.
2310 ** The following macros take advantage this fact to provide a fast encode
2311 ** and decode of the integers in a record header.  It is faster for the common
2312 ** case where the integer is a single byte.  It is a little slower when the
2313 ** integer is two or more bytes.  But overall it is faster.
2314 **
2315 ** The following expressions are equivalent:
2316 **
2317 **     x = sqlite3GetVarint32( A, &B );
2318 **     x = sqlite3PutVarint32( A, B );
2319 **
2320 **     x = getVarint32( A, B );
2321 **     x = putVarint32( A, B );
2322 **
2323 */
2324 #define getVarint32(A,B)  ((*(A)<(unsigned char)0x80) ? ((B) = (u32)*(A)),1 : sqlite3GetVarint32((A), &(B)))
2325 #define putVarint32(A,B)  (((B)<(u32)0x80) ? (*(A) = (unsigned char)(B)),1 : sqlite3PutVarint32((A), (B)))
2326 #define getVarint    sqlite3GetVarint
2327 #define putVarint    sqlite3PutVarint
2328 
2329 
2330 void sqlite3IndexAffinityStr(Vdbe *, Index *);
2331 void sqlite3TableAffinityStr(Vdbe *, Table *);
2332 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
2333 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
2334 char sqlite3ExprAffinity(Expr *pExpr);
2335 int sqlite3Atoi64(const char*, i64*);
2336 void sqlite3Error(sqlite3*, int, const char*,...);
2337 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
2338 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
2339 const char *sqlite3ErrStr(int);
2340 int sqlite3ReadSchema(Parse *pParse);
2341 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char *,int,int);
2342 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName, int nName);
2343 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
2344 Expr *sqlite3ExprSetColl(Parse *pParse, Expr *, Token *);
2345 int sqlite3CheckCollSeq(Parse *, CollSeq *);
2346 int sqlite3CheckObjectName(Parse *, const char *);
2347 void sqlite3VdbeSetChanges(sqlite3 *, int);
2348 
2349 const void *sqlite3ValueText(sqlite3_value*, u8);
2350 int sqlite3ValueBytes(sqlite3_value*, u8);
2351 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
2352                         void(*)(void*));
2353 void sqlite3ValueFree(sqlite3_value*);
2354 sqlite3_value *sqlite3ValueNew(sqlite3 *);
2355 char *sqlite3Utf16to8(sqlite3 *, const void*, int);
2356 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
2357 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
2358 #ifndef SQLITE_AMALGAMATION
2359 extern const unsigned char sqlite3UpperToLower[];
2360 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
2361 extern SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
2362 #endif
2363 void sqlite3RootPageMoved(Db*, int, int);
2364 void sqlite3Reindex(Parse*, Token*, Token*);
2365 void sqlite3AlterFunctions(sqlite3*);
2366 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
2367 int sqlite3GetToken(const unsigned char *, int *);
2368 void sqlite3NestedParse(Parse*, const char*, ...);
2369 void sqlite3ExpirePreparedStatements(sqlite3*);
2370 void sqlite3CodeSubselect(Parse *, Expr *, int);
2371 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
2372 int sqlite3ResolveExprNames(NameContext*, Expr*);
2373 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
2374 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
2375 void sqlite3ColumnDefault(Vdbe *, Table *, int);
2376 void sqlite3AlterFinishAddColumn(Parse *, Token *);
2377 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
2378 CollSeq *sqlite3GetCollSeq(sqlite3*, CollSeq *, const char *, int);
2379 char sqlite3AffinityType(const Token*);
2380 void sqlite3Analyze(Parse*, Token*, Token*);
2381 int sqlite3InvokeBusyHandler(BusyHandler*);
2382 int sqlite3FindDb(sqlite3*, Token*);
2383 int sqlite3AnalysisLoad(sqlite3*,int iDB);
2384 void sqlite3DefaultRowEst(Index*);
2385 void sqlite3RegisterLikeFunctions(sqlite3*, int);
2386 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
2387 void sqlite3AttachFunctions(sqlite3 *);
2388 void sqlite3MinimumFileFormat(Parse*, int, int);
2389 void sqlite3SchemaFree(void *);
2390 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
2391 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
2392 KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
2393 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
2394   void (*)(sqlite3_context*,int,sqlite3_value **),
2395   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*));
2396 int sqlite3ApiExit(sqlite3 *db, int);
2397 int sqlite3OpenTempDatabase(Parse *);
2398 
2399 void sqlite3StrAccumInit(StrAccum*, char*, int, int);
2400 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
2401 char *sqlite3StrAccumFinish(StrAccum*);
2402 void sqlite3StrAccumReset(StrAccum*);
2403 void sqlite3SelectDestInit(SelectDest*,int,int);
2404 
2405 /*
2406 ** The interface to the LEMON-generated parser
2407 */
2408 void *sqlite3ParserAlloc(void*(*)(size_t));
2409 void sqlite3ParserFree(void*, void(*)(void*));
2410 void sqlite3Parser(void*, int, Token, Parse*);
2411 #ifdef YYTRACKMAXSTACKDEPTH
2412   int sqlite3ParserStackPeak(void*);
2413 #endif
2414 
2415 int sqlite3AutoLoadExtensions(sqlite3*);
2416 #ifndef SQLITE_OMIT_LOAD_EXTENSION
2417   void sqlite3CloseExtensions(sqlite3*);
2418 #else
2419 # define sqlite3CloseExtensions(X)
2420 #endif
2421 
2422 #ifndef SQLITE_OMIT_SHARED_CACHE
2423   void sqlite3TableLock(Parse *, int, int, u8, const char *);
2424 #else
2425   #define sqlite3TableLock(v,w,x,y,z)
2426 #endif
2427 
2428 #ifdef SQLITE_TEST
2429   int sqlite3Utf8To8(unsigned char*);
2430 #endif
2431 
2432 #ifdef SQLITE_OMIT_VIRTUALTABLE
2433 #  define sqlite3VtabClear(X)
2434 #  define sqlite3VtabSync(X,Y) SQLITE_OK
2435 #  define sqlite3VtabRollback(X)
2436 #  define sqlite3VtabCommit(X)
2437 #else
2438    void sqlite3VtabClear(Table*);
2439    int sqlite3VtabSync(sqlite3 *db, char **);
2440    int sqlite3VtabRollback(sqlite3 *db);
2441    int sqlite3VtabCommit(sqlite3 *db);
2442 #endif
2443 void sqlite3VtabMakeWritable(Parse*,Table*);
2444 void sqlite3VtabLock(sqlite3_vtab*);
2445 void sqlite3VtabUnlock(sqlite3*, sqlite3_vtab*);
2446 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*);
2447 void sqlite3VtabFinishParse(Parse*, Token*);
2448 void sqlite3VtabArgInit(Parse*);
2449 void sqlite3VtabArgExtend(Parse*, Token*);
2450 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
2451 int sqlite3VtabCallConnect(Parse*, Table*);
2452 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
2453 int sqlite3VtabBegin(sqlite3 *, sqlite3_vtab *);
2454 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
2455 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
2456 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
2457 int sqlite3Reprepare(Vdbe*);
2458 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
2459 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
2460 
2461 
2462 /*
2463 ** Available fault injectors.  Should be numbered beginning with 0.
2464 */
2465 #define SQLITE_FAULTINJECTOR_MALLOC     0
2466 #define SQLITE_FAULTINJECTOR_COUNT      1
2467 
2468 /*
2469 ** The interface to the code in fault.c used for identifying "benign"
2470 ** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
2471 ** is not defined.
2472 */
2473 #ifndef SQLITE_OMIT_BUILTIN_TEST
2474   void sqlite3BeginBenignMalloc(void);
2475   void sqlite3EndBenignMalloc(void);
2476 #else
2477   #define sqlite3BeginBenignMalloc()
2478   #define sqlite3EndBenignMalloc()
2479 #endif
2480 
2481 #define IN_INDEX_ROWID           1
2482 #define IN_INDEX_EPH             2
2483 #define IN_INDEX_INDEX           3
2484 int sqlite3FindInIndex(Parse *, Expr *, int*);
2485 
2486 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
2487   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
2488   int sqlite3JournalSize(sqlite3_vfs *);
2489   int sqlite3JournalCreate(sqlite3_file *);
2490 #else
2491   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
2492 #endif
2493 
2494 #if SQLITE_MAX_EXPR_DEPTH>0
2495   void sqlite3ExprSetHeight(Parse *pParse, Expr *p);
2496   int sqlite3SelectExprHeight(Select *);
2497   int sqlite3ExprCheckHeight(Parse*, int);
2498 #else
2499   #define sqlite3ExprSetHeight(x,y)
2500   #define sqlite3SelectExprHeight(x) 0
2501   #define sqlite3ExprCheckHeight(x,y)
2502 #endif
2503 
2504 u32 sqlite3Get4byte(const u8*);
2505 void sqlite3Put4byte(u8*, u32);
2506 
2507 #ifdef SQLITE_SSE
2508 #include "sseInt.h"
2509 #endif
2510 
2511 #ifdef SQLITE_DEBUG
2512   void sqlite3ParserTrace(FILE*, char *);
2513 #endif
2514 
2515 /*
2516 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
2517 ** sqlite3IoTrace is a pointer to a printf-like routine used to
2518 ** print I/O tracing messages.
2519 */
2520 #ifdef SQLITE_ENABLE_IOTRACE
2521 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
2522   void sqlite3VdbeIOTraceSql(Vdbe*);
2523 SQLITE_EXTERN void (*sqlite3IoTrace)(const char*,...);
2524 #else
2525 # define IOTRACE(A)
2526 # define sqlite3VdbeIOTraceSql(X)
2527 #endif
2528 
2529 #endif
2530