xref: /sqlite-3.40.0/src/sqliteInt.h (revision 85b623f2)
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 1.626 2007/12/13 03:45:08 drh Exp $
15 */
16 #ifndef _SQLITEINT_H_
17 #define _SQLITEINT_H_
18 
19 /*
20 ** The macro unlikely() is a hint that surrounds a boolean
21 ** expression that is usually false.  Macro likely() surrounds
22 ** a boolean expression that is usually true.  GCC is able to
23 ** use these hints to generate better code, sometimes.
24 */
25 #if defined(__GNUC__)
26 # define likely(X)    __builtin_expect((X),1)
27 # define unlikely(X)  __builtin_expect((X),0)
28 #else
29 # define likely(X)    !!(X)
30 # define unlikely(X)  !!(X)
31 #endif
32 
33 
34 /*
35 ** These #defines should enable >2GB file support on Posix if the
36 ** underlying operating system supports it.  If the OS lacks
37 ** large file support, or if the OS is windows, these should be no-ops.
38 **
39 ** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
40 ** system #includes.  Hence, this block of code must be the very first
41 ** code in all source files.
42 **
43 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
44 ** on the compiler command line.  This is necessary if you are compiling
45 ** on a recent machine (ex: RedHat 7.2) but you want your code to work
46 ** on an older machine (ex: RedHat 6.0).  If you compile on RedHat 7.2
47 ** without this option, LFS is enable.  But LFS does not exist in the kernel
48 ** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
49 ** portability you should omit LFS.
50 **
51 ** Similar is true for MacOS.  LFS is only supported on MacOS 9 and later.
52 */
53 #ifndef SQLITE_DISABLE_LFS
54 # define _LARGE_FILE       1
55 # ifndef _FILE_OFFSET_BITS
56 #   define _FILE_OFFSET_BITS 64
57 # endif
58 # define _LARGEFILE_SOURCE 1
59 #endif
60 
61 
62 #include "sqliteLimit.h"
63 
64 /*
65 ** For testing purposes, the various size limit constants are really
66 ** variables that we can modify in the testfixture.
67 */
68 #ifdef SQLITE_TEST
69   #undef SQLITE_MAX_LENGTH
70   #undef SQLITE_MAX_COLUMN
71   #undef SQLITE_MAX_SQL_LENGTH
72   #undef SQLITE_MAX_EXPR_DEPTH
73   #undef SQLITE_MAX_COMPOUND_SELECT
74   #undef SQLITE_MAX_VDBE_OP
75   #undef SQLITE_MAX_FUNCTION_ARG
76   #undef SQLITE_MAX_VARIABLE_NUMBER
77   #undef SQLITE_MAX_PAGE_SIZE
78   #undef SQLITE_MAX_PAGE_COUNT
79   #undef SQLITE_MAX_LIKE_PATTERN_LENGTH
80 
81   #define SQLITE_MAX_LENGTH              sqlite3MAX_LENGTH
82   #define SQLITE_MAX_COLUMN              sqlite3MAX_COLUMN
83   #define SQLITE_MAX_SQL_LENGTH          sqlite3MAX_SQL_LENGTH
84   #define SQLITE_MAX_EXPR_DEPTH          sqlite3MAX_EXPR_DEPTH
85   #define SQLITE_MAX_COMPOUND_SELECT     sqlite3MAX_COMPOUND_SELECT
86   #define SQLITE_MAX_VDBE_OP             sqlite3MAX_VDBE_OP
87   #define SQLITE_MAX_FUNCTION_ARG        sqlite3MAX_FUNCTION_ARG
88   #define SQLITE_MAX_VARIABLE_NUMBER     sqlite3MAX_VARIABLE_NUMBER
89   #define SQLITE_MAX_PAGE_SIZE           sqlite3MAX_PAGE_SIZE
90   #define SQLITE_MAX_PAGE_COUNT          sqlite3MAX_PAGE_COUNT
91   #define SQLITE_MAX_LIKE_PATTERN_LENGTH sqlite3MAX_LIKE_PATTERN_LENGTH
92 
93   extern int sqlite3MAX_LENGTH;
94   extern int sqlite3MAX_COLUMN;
95   extern int sqlite3MAX_SQL_LENGTH;
96   extern int sqlite3MAX_EXPR_DEPTH;
97   extern int sqlite3MAX_COMPOUND_SELECT;
98   extern int sqlite3MAX_VDBE_OP;
99   extern int sqlite3MAX_FUNCTION_ARG;
100   extern int sqlite3MAX_VARIABLE_NUMBER;
101   extern int sqlite3MAX_PAGE_SIZE;
102   extern int sqlite3MAX_PAGE_COUNT;
103   extern int sqlite3MAX_LIKE_PATTERN_LENGTH;
104 #endif
105 
106 
107 /*
108 ** The SQLITE_THREADSAFE macro must be defined as either 0 or 1.
109 ** Older versions of SQLite used an optional THREADSAFE macro.
110 ** We support that for legacy
111 */
112 #if !defined(SQLITE_THREADSAFE)
113 #if defined(THREADSAFE)
114 # define SQLITE_THREADSAFE THREADSAFE
115 #else
116 # define SQLITE_THREADSAFE 1
117 #endif
118 #endif
119 
120 /*
121 ** We need to define _XOPEN_SOURCE as follows in order to enable
122 ** recursive mutexes on most unix systems.  But Mac OS X is different.
123 ** The _XOPEN_SOURCE define causes problems for Mac OS X we are told,
124 ** so it is omitted there.  See ticket #2673.
125 **
126 ** Later we learn that _XOPEN_SOURCE is poorly or incorrectly
127 ** implemented on some systems.  So we avoid defining it at all
128 ** if it is already defined or if it is unneeded because we are
129 ** not doing a threadsafe build.  Ticket #2681.
130 **
131 ** See also ticket #2741.
132 */
133 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && SQLITE_THREADSAFE
134 #  define _XOPEN_SOURCE 500  /* Needed to enable pthread recursive mutexes */
135 #endif
136 
137 #if defined(SQLITE_TCL) || defined(TCLSH)
138 # include <tcl.h>
139 #endif
140 
141 /*
142 ** Many people are failing to set -DNDEBUG=1 when compiling SQLite.
143 ** Setting NDEBUG makes the code smaller and run faster.  So the following
144 ** lines are added to automatically set NDEBUG unless the -DSQLITE_DEBUG=1
145 ** option is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
146 ** feature.
147 */
148 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
149 # define NDEBUG 1
150 #endif
151 
152 #include "sqlite3.h"
153 #include "hash.h"
154 #include "parse.h"
155 #include <stdio.h>
156 #include <stdlib.h>
157 #include <string.h>
158 #include <assert.h>
159 #include <stddef.h>
160 
161 #define sqlite3_isnan(X)  ((X)!=(X))
162 
163 /*
164 ** If compiling for a processor that lacks floating point support,
165 ** substitute integer for floating-point
166 */
167 #ifdef SQLITE_OMIT_FLOATING_POINT
168 # define double sqlite_int64
169 # define LONGDOUBLE_TYPE sqlite_int64
170 # ifndef SQLITE_BIG_DBL
171 #   define SQLITE_BIG_DBL (0x7fffffffffffffff)
172 # endif
173 # define SQLITE_OMIT_DATETIME_FUNCS 1
174 # define SQLITE_OMIT_TRACE 1
175 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
176 #endif
177 #ifndef SQLITE_BIG_DBL
178 # define SQLITE_BIG_DBL (1e99)
179 #endif
180 
181 /*
182 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
183 ** afterward. Having this macro allows us to cause the C compiler
184 ** to omit code used by TEMP tables without messy #ifndef statements.
185 */
186 #ifdef SQLITE_OMIT_TEMPDB
187 #define OMIT_TEMPDB 1
188 #else
189 #define OMIT_TEMPDB 0
190 #endif
191 
192 /*
193 ** If the following macro is set to 1, then NULL values are considered
194 ** distinct when determining whether or not two entries are the same
195 ** in a UNIQUE index.  This is the way PostgreSQL, Oracle, DB2, MySQL,
196 ** OCELOT, and Firebird all work.  The SQL92 spec explicitly says this
197 ** is the way things are suppose to work.
198 **
199 ** If the following macro is set to 0, the NULLs are indistinct for
200 ** a UNIQUE index.  In this mode, you can only have a single NULL entry
201 ** for a column declared UNIQUE.  This is the way Informix and SQL Server
202 ** work.
203 */
204 #define NULL_DISTINCT_FOR_UNIQUE 1
205 
206 /*
207 ** The "file format" number is an integer that is incremented whenever
208 ** the VDBE-level file format changes.  The following macros define the
209 ** the default file format for new databases and the maximum file format
210 ** that the library can read.
211 */
212 #define SQLITE_MAX_FILE_FORMAT 4
213 #ifndef SQLITE_DEFAULT_FILE_FORMAT
214 # define SQLITE_DEFAULT_FILE_FORMAT 1
215 #endif
216 
217 /*
218 ** Provide a default value for TEMP_STORE in case it is not specified
219 ** on the command-line
220 */
221 #ifndef TEMP_STORE
222 # define TEMP_STORE 1
223 #endif
224 
225 /*
226 ** GCC does not define the offsetof() macro so we'll have to do it
227 ** ourselves.
228 */
229 #ifndef offsetof
230 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
231 #endif
232 
233 /*
234 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
235 ** not, there are still machines out there that use EBCDIC.)
236 */
237 #if 'A' == '\301'
238 # define SQLITE_EBCDIC 1
239 #else
240 # define SQLITE_ASCII 1
241 #endif
242 
243 /*
244 ** Integers of known sizes.  These typedefs might change for architectures
245 ** where the sizes very.  Preprocessor macros are available so that the
246 ** types can be conveniently redefined at compile-type.  Like this:
247 **
248 **         cc '-DUINTPTR_TYPE=long long int' ...
249 */
250 #ifndef UINT32_TYPE
251 # define UINT32_TYPE unsigned int
252 #endif
253 #ifndef UINT16_TYPE
254 # define UINT16_TYPE unsigned short int
255 #endif
256 #ifndef INT16_TYPE
257 # define INT16_TYPE short int
258 #endif
259 #ifndef UINT8_TYPE
260 # define UINT8_TYPE unsigned char
261 #endif
262 #ifndef INT8_TYPE
263 # define INT8_TYPE signed char
264 #endif
265 #ifndef LONGDOUBLE_TYPE
266 # define LONGDOUBLE_TYPE long double
267 #endif
268 typedef sqlite_int64 i64;          /* 8-byte signed integer */
269 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
270 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
271 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
272 typedef INT16_TYPE i16;            /* 2-byte signed integer */
273 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
274 typedef UINT8_TYPE i8;             /* 1-byte signed integer */
275 
276 /*
277 ** Macros to determine whether the machine is big or little endian,
278 ** evaluated at runtime.
279 */
280 #ifdef SQLITE_AMALGAMATION
281 const int sqlite3One;
282 #else
283 extern const int sqlite3one;
284 #endif
285 #if defined(i386) || defined(__i386__) || defined(_M_IX86)
286 # define SQLITE_BIGENDIAN    0
287 # define SQLITE_LITTLEENDIAN 1
288 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
289 #else
290 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
291 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
292 # define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
293 #endif
294 
295 /*
296 ** An instance of the following structure is used to store the busy-handler
297 ** callback for a given sqlite handle.
298 **
299 ** The sqlite.busyHandler member of the sqlite struct contains the busy
300 ** callback for the database handle. Each pager opened via the sqlite
301 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
302 ** callback is currently invoked only from within pager.c.
303 */
304 typedef struct BusyHandler BusyHandler;
305 struct BusyHandler {
306   int (*xFunc)(void *,int);  /* The busy callback */
307   void *pArg;                /* First arg to busy callback */
308   int nBusy;                 /* Incremented with each busy call */
309 };
310 
311 /*
312 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
313 ** "BusyHandler typedefs.
314 */
315 #include "btree.h"
316 #include "vdbe.h"
317 #include "pager.h"
318 
319 
320 /*
321 ** Name of the master database table.  The master database table
322 ** is a special table that holds the names and attributes of all
323 ** user tables and indices.
324 */
325 #define MASTER_NAME       "sqlite_master"
326 #define TEMP_MASTER_NAME  "sqlite_temp_master"
327 
328 /*
329 ** The root-page of the master database table.
330 */
331 #define MASTER_ROOT       1
332 
333 /*
334 ** The name of the schema table.
335 */
336 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
337 
338 /*
339 ** A convenience macro that returns the number of elements in
340 ** an array.
341 */
342 #define ArraySize(X)    (sizeof(X)/sizeof(X[0]))
343 
344 /*
345 ** Forward references to structures
346 */
347 typedef struct AggInfo AggInfo;
348 typedef struct AuthContext AuthContext;
349 typedef struct CollSeq CollSeq;
350 typedef struct Column Column;
351 typedef struct Db Db;
352 typedef struct Schema Schema;
353 typedef struct Expr Expr;
354 typedef struct ExprList ExprList;
355 typedef struct FKey FKey;
356 typedef struct FuncDef FuncDef;
357 typedef struct IdList IdList;
358 typedef struct Index Index;
359 typedef struct KeyClass KeyClass;
360 typedef struct KeyInfo KeyInfo;
361 typedef struct Module Module;
362 typedef struct NameContext NameContext;
363 typedef struct Parse Parse;
364 typedef struct Select Select;
365 typedef struct SrcList SrcList;
366 typedef struct StrAccum StrAccum;
367 typedef struct Table Table;
368 typedef struct TableLock TableLock;
369 typedef struct Token Token;
370 typedef struct TriggerStack TriggerStack;
371 typedef struct TriggerStep TriggerStep;
372 typedef struct Trigger Trigger;
373 typedef struct WhereInfo WhereInfo;
374 typedef struct WhereLevel WhereLevel;
375 
376 #include "os.h"
377 #include "mutex.h"
378 
379 /*
380 ** Each database file to be accessed by the system is an instance
381 ** of the following structure.  There are normally two of these structures
382 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
383 ** aDb[1] is the database file used to hold temporary tables.  Additional
384 ** databases may be attached.
385 */
386 struct Db {
387   char *zName;         /* Name of this database */
388   Btree *pBt;          /* The B*Tree structure for this database file */
389   u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
390   u8 safety_level;     /* How aggressive at synching data to disk */
391   void *pAux;               /* Auxiliary data.  Usually NULL */
392   void (*xFreeAux)(void*);  /* Routine to free pAux */
393   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
394 };
395 
396 /*
397 ** An instance of the following structure stores a database schema.
398 **
399 ** If there are no virtual tables configured in this schema, the
400 ** Schema.db variable is set to NULL. After the first virtual table
401 ** has been added, it is set to point to the database connection
402 ** used to create the connection. Once a virtual table has been
403 ** added to the Schema structure and the Schema.db variable populated,
404 ** only that database connection may use the Schema to prepare
405 ** statements.
406 */
407 struct Schema {
408   int schema_cookie;   /* Database schema version number for this file */
409   Hash tblHash;        /* All tables indexed by name */
410   Hash idxHash;        /* All (named) indices indexed by name */
411   Hash trigHash;       /* All triggers indexed by name */
412   Hash aFKey;          /* Foreign keys indexed by to-table */
413   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
414   u8 file_format;      /* Schema format version for this file */
415   u8 enc;              /* Text encoding used by this database */
416   u16 flags;           /* Flags associated with this schema */
417   int cache_size;      /* Number of pages to use in the cache */
418 #ifndef SQLITE_OMIT_VIRTUALTABLE
419   sqlite3 *db;         /* "Owner" connection. See comment above */
420 #endif
421 };
422 
423 /*
424 ** These macros can be used to test, set, or clear bits in the
425 ** Db.flags field.
426 */
427 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->flags&(P))==(P))
428 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->flags&(P))!=0)
429 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->flags|=(P)
430 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->flags&=~(P)
431 
432 /*
433 ** Allowed values for the DB.flags field.
434 **
435 ** The DB_SchemaLoaded flag is set after the database schema has been
436 ** read into internal hash tables.
437 **
438 ** DB_UnresetViews means that one or more views have column names that
439 ** have been filled out.  If the schema changes, these column names might
440 ** changes and so the view will need to be reset.
441 */
442 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
443 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
444 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
445 
446 
447 /*
448 ** Each database is an instance of the following structure.
449 **
450 ** The sqlite.lastRowid records the last insert rowid generated by an
451 ** insert statement.  Inserts on views do not affect its value.  Each
452 ** trigger has its own context, so that lastRowid can be updated inside
453 ** triggers as usual.  The previous value will be restored once the trigger
454 ** exits.  Upon entering a before or instead of trigger, lastRowid is no
455 ** longer (since after version 2.8.12) reset to -1.
456 **
457 ** The sqlite.nChange does not count changes within triggers and keeps no
458 ** context.  It is reset at start of sqlite3_exec.
459 ** The sqlite.lsChange represents the number of changes made by the last
460 ** insert, update, or delete statement.  It remains constant throughout the
461 ** length of a statement and is then updated by OP_SetCounts.  It keeps a
462 ** context stack just like lastRowid so that the count of changes
463 ** within a trigger is not seen outside the trigger.  Changes to views do not
464 ** affect the value of lsChange.
465 ** The sqlite.csChange keeps track of the number of current changes (since
466 ** the last statement) and is used to update sqlite_lsChange.
467 **
468 ** The member variables sqlite.errCode, sqlite.zErrMsg and sqlite.zErrMsg16
469 ** store the most recent error code and, if applicable, string. The
470 ** internal function sqlite3Error() is used to set these variables
471 ** consistently.
472 */
473 struct sqlite3 {
474   sqlite3_vfs *pVfs;            /* OS Interface */
475   int nDb;                      /* Number of backends currently in use */
476   Db *aDb;                      /* All backends */
477   int flags;                    /* Miscellanous flags. See below */
478   int openFlags;                /* Flags passed to sqlite3_vfs.xOpen() */
479   int errCode;                  /* Most recent error code (SQLITE_*) */
480   int errMask;                  /* & result codes with this before returning */
481   u8 autoCommit;                /* The auto-commit flag. */
482   u8 temp_store;                /* 1: file 2: memory 0: default */
483   u8 mallocFailed;              /* True if we have seen a malloc failure */
484   char nextAutovac;             /* Autovac setting after VACUUM if >=0 */
485   int nTable;                   /* Number of tables in the database */
486   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
487   i64 lastRowid;                /* ROWID of most recent insert (see above) */
488   i64 priorNewRowid;            /* Last randomly generated ROWID */
489   int magic;                    /* Magic number for detect library misuse */
490   int nChange;                  /* Value returned by sqlite3_changes() */
491   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
492   sqlite3_mutex *mutex;         /* Connection mutex */
493   struct sqlite3InitInfo {      /* Information used during initialization */
494     int iDb;                    /* When back is being initialized */
495     int newTnum;                /* Rootpage of table being initialized */
496     u8 busy;                    /* TRUE if currently initializing */
497   } init;
498   int nExtension;               /* Number of loaded extensions */
499   void **aExtension;            /* Array of shared libraray handles */
500   struct Vdbe *pVdbe;           /* List of active virtual machines */
501   int activeVdbeCnt;            /* Number of vdbes currently executing */
502   void (*xTrace)(void*,const char*);        /* Trace function */
503   void *pTraceArg;                          /* Argument to the trace function */
504   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
505   void *pProfileArg;                        /* Argument to profile function */
506   void *pCommitArg;                 /* Argument to xCommitCallback() */
507   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
508   void *pRollbackArg;               /* Argument to xRollbackCallback() */
509   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
510   void *pUpdateArg;
511   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
512   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
513   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
514   void *pCollNeededArg;
515   sqlite3_value *pErr;          /* Most recent error message */
516   char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
517   char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
518   union {
519     int isInterrupted;          /* True if sqlite3_interrupt has been called */
520     double notUsed1;            /* Spacer */
521   } u1;
522 #ifndef SQLITE_OMIT_AUTHORIZATION
523   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
524                                 /* Access authorization function */
525   void *pAuthArg;               /* 1st argument to the access auth function */
526 #endif
527 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
528   int (*xProgress)(void *);     /* The progress callback */
529   void *pProgressArg;           /* Argument to the progress callback */
530   int nProgressOps;             /* Number of opcodes for progress callback */
531 #endif
532 #ifndef SQLITE_OMIT_VIRTUALTABLE
533   Hash aModule;                 /* populated by sqlite3_create_module() */
534   Table *pVTab;                 /* vtab with active Connect/Create method */
535   sqlite3_vtab **aVTrans;       /* Virtual tables with open transactions */
536   int nVTrans;                  /* Allocated size of aVTrans */
537 #endif
538   Hash aFunc;                   /* All functions that can be in SQL exprs */
539   Hash aCollSeq;                /* All collating sequences */
540   BusyHandler busyHandler;      /* Busy callback */
541   int busyTimeout;              /* Busy handler timeout, in msec */
542   Db aDbStatic[2];              /* Static space for the 2 default backends */
543 #ifdef SQLITE_SSE
544   sqlite3_stmt *pFetch;         /* Used by SSE to fetch stored statements */
545 #endif
546   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
547 };
548 
549 /*
550 ** A macro to discover the encoding of a database.
551 */
552 #define ENC(db) ((db)->aDb[0].pSchema->enc)
553 
554 /*
555 ** Possible values for the sqlite.flags and or Db.flags fields.
556 **
557 ** On sqlite.flags, the SQLITE_InTrans value means that we have
558 ** executed a BEGIN.  On Db.flags, SQLITE_InTrans means a statement
559 ** transaction is active on that particular database file.
560 */
561 #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
562 #define SQLITE_InTrans        0x00000008  /* True if in a transaction */
563 #define SQLITE_InternChanges  0x00000010  /* Uncommitted Hash table changes */
564 #define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
565 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
566 #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
567                                           /*   DELETE, or UPDATE and return */
568                                           /*   the count using a callback. */
569 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
570                                           /*   result set is empty */
571 #define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
572 #define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
573 #define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
574 #define SQLITE_NoReadlock     0x00001000  /* Readlocks are omitted when
575                                           ** accessing read-only databases */
576 #define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
577 #define SQLITE_ReadUncommitted 0x00004000 /* For shared-cache mode */
578 #define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
579 #define SQLITE_FullFSync      0x00010000  /* Use full fsync on the backend */
580 #define SQLITE_LoadExtension  0x00020000  /* Enable load_extension */
581 
582 #define SQLITE_RecoveryMode   0x00040000  /* Ignore schema errors */
583 #define SQLITE_SharedCache    0x00080000  /* Cache sharing is enabled */
584 #define SQLITE_Vtab           0x00100000  /* There exists a virtual table */
585 
586 /*
587 ** Possible values for the sqlite.magic field.
588 ** The numbers are obtained at random and have no special meaning, other
589 ** than being distinct from one another.
590 */
591 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
592 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
593 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
594 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
595 
596 /*
597 ** Each SQL function is defined by an instance of the following
598 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
599 ** hash table.  When multiple functions have the same name, the hash table
600 ** points to a linked list of these structures.
601 */
602 struct FuncDef {
603   i16 nArg;            /* Number of arguments.  -1 means unlimited */
604   u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
605   u8 needCollSeq;      /* True if sqlite3GetFuncCollSeq() might be called */
606   u8 flags;            /* Some combination of SQLITE_FUNC_* */
607   void *pUserData;     /* User data parameter */
608   FuncDef *pNext;      /* Next function with same name */
609   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
610   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
611   void (*xFinalize)(sqlite3_context*);                /* Aggregate finializer */
612   char zName[1];       /* SQL name of the function.  MUST BE LAST */
613 };
614 
615 /*
616 ** Each SQLite module (virtual table definition) is defined by an
617 ** instance of the following structure, stored in the sqlite3.aModule
618 ** hash table.
619 */
620 struct Module {
621   const sqlite3_module *pModule;       /* Callback pointers */
622   const char *zName;                   /* Name passed to create_module() */
623   void *pAux;                          /* pAux passed to create_module() */
624   void (*xDestroy)(void *);            /* Module destructor function */
625 };
626 
627 /*
628 ** Possible values for FuncDef.flags
629 */
630 #define SQLITE_FUNC_LIKE   0x01  /* Candidate for the LIKE optimization */
631 #define SQLITE_FUNC_CASE   0x02  /* Case-sensitive LIKE-type function */
632 #define SQLITE_FUNC_EPHEM  0x04  /* Ephermeral.  Delete with VDBE */
633 
634 /*
635 ** information about each column of an SQL table is held in an instance
636 ** of this structure.
637 */
638 struct Column {
639   char *zName;     /* Name of this column */
640   Expr *pDflt;     /* Default value of this column */
641   char *zType;     /* Data type for this column */
642   char *zColl;     /* Collating sequence.  If NULL, use the default */
643   u8 notNull;      /* True if there is a NOT NULL constraint */
644   u8 isPrimKey;    /* True if this column is part of the PRIMARY KEY */
645   char affinity;   /* One of the SQLITE_AFF_... values */
646 #ifndef SQLITE_OMIT_VIRTUALTABLE
647   u8 isHidden;     /* True if this column is 'hidden' */
648 #endif
649 };
650 
651 /*
652 ** A "Collating Sequence" is defined by an instance of the following
653 ** structure. Conceptually, a collating sequence consists of a name and
654 ** a comparison routine that defines the order of that sequence.
655 **
656 ** There may two seperate implementations of the collation function, one
657 ** that processes text in UTF-8 encoding (CollSeq.xCmp) and another that
658 ** processes text encoded in UTF-16 (CollSeq.xCmp16), using the machine
659 ** native byte order. When a collation sequence is invoked, SQLite selects
660 ** the version that will require the least expensive encoding
661 ** translations, if any.
662 **
663 ** The CollSeq.pUser member variable is an extra parameter that passed in
664 ** as the first argument to the UTF-8 comparison function, xCmp.
665 ** CollSeq.pUser16 is the equivalent for the UTF-16 comparison function,
666 ** xCmp16.
667 **
668 ** If both CollSeq.xCmp and CollSeq.xCmp16 are NULL, it means that the
669 ** collating sequence is undefined.  Indices built on an undefined
670 ** collating sequence may not be read or written.
671 */
672 struct CollSeq {
673   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
674   u8 enc;               /* Text encoding handled by xCmp() */
675   u8 type;              /* One of the SQLITE_COLL_... values below */
676   void *pUser;          /* First argument to xCmp() */
677   int (*xCmp)(void*,int, const void*, int, const void*);
678   void (*xDel)(void*);  /* Destructor for pUser */
679 };
680 
681 /*
682 ** Allowed values of CollSeq flags:
683 */
684 #define SQLITE_COLL_BINARY  1  /* The default memcmp() collating sequence */
685 #define SQLITE_COLL_NOCASE  2  /* The built-in NOCASE collating sequence */
686 #define SQLITE_COLL_REVERSE 3  /* The built-in REVERSE collating sequence */
687 #define SQLITE_COLL_USER    0  /* Any other user-defined collating sequence */
688 
689 /*
690 ** A sort order can be either ASC or DESC.
691 */
692 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
693 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
694 
695 /*
696 ** Column affinity types.
697 **
698 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
699 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
700 ** the speed a little by number the values consecutively.
701 **
702 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
703 ** when multiple affinity types are concatenated into a string and
704 ** used as the P3 operand, they will be more readable.
705 **
706 ** Note also that the numeric types are grouped together so that testing
707 ** for a numeric type is a single comparison.
708 */
709 #define SQLITE_AFF_TEXT     'a'
710 #define SQLITE_AFF_NONE     'b'
711 #define SQLITE_AFF_NUMERIC  'c'
712 #define SQLITE_AFF_INTEGER  'd'
713 #define SQLITE_AFF_REAL     'e'
714 
715 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
716 
717 /*
718 ** Each SQL table is represented in memory by an instance of the
719 ** following structure.
720 **
721 ** Table.zName is the name of the table.  The case of the original
722 ** CREATE TABLE statement is stored, but case is not significant for
723 ** comparisons.
724 **
725 ** Table.nCol is the number of columns in this table.  Table.aCol is a
726 ** pointer to an array of Column structures, one for each column.
727 **
728 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
729 ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
730 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
731 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
732 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
733 ** is generated for each row of the table.  Table.hasPrimKey is true if
734 ** the table has any PRIMARY KEY, INTEGER or otherwise.
735 **
736 ** Table.tnum is the page number for the root BTree page of the table in the
737 ** database file.  If Table.iDb is the index of the database table backend
738 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
739 ** holds temporary tables and indices.  If Table.isEphem
740 ** is true, then the table is stored in a file that is automatically deleted
741 ** when the VDBE cursor to the table is closed.  In this case Table.tnum
742 ** refers VDBE cursor number that holds the table open, not to the root
743 ** page number.  Transient tables are used to hold the results of a
744 ** sub-query that appears instead of a real table name in the FROM clause
745 ** of a SELECT statement.
746 */
747 struct Table {
748   char *zName;     /* Name of the table */
749   int nCol;        /* Number of columns in this table */
750   Column *aCol;    /* Information about each column */
751   int iPKey;       /* If not less then 0, use aCol[iPKey] as the primary key */
752   Index *pIndex;   /* List of SQL indexes on this table. */
753   int tnum;        /* Root BTree node for this table (see note above) */
754   Select *pSelect; /* NULL for tables.  Points to definition if a view. */
755   int nRef;          /* Number of pointers to this Table */
756   Trigger *pTrigger; /* List of SQL triggers on this table */
757   FKey *pFKey;       /* Linked list of all foreign keys in this table */
758   char *zColAff;     /* String defining the affinity of each column */
759 #ifndef SQLITE_OMIT_CHECK
760   Expr *pCheck;      /* The AND of all CHECK constraints */
761 #endif
762 #ifndef SQLITE_OMIT_ALTERTABLE
763   int addColOffset;  /* Offset in CREATE TABLE statement to add a new column */
764 #endif
765   u8 readOnly;     /* True if this table should not be written by the user */
766   u8 isEphem;      /* True if created using OP_OpenEphermeral */
767   u8 hasPrimKey;   /* True if there exists a primary key */
768   u8 keyConf;      /* What to do in case of uniqueness conflict on iPKey */
769   u8 autoInc;      /* True if the integer primary key is autoincrement */
770 #ifndef SQLITE_OMIT_VIRTUALTABLE
771   u8 isVirtual;             /* True if this is a virtual table */
772   u8 isCommit;              /* True once the CREATE TABLE has been committed */
773   Module *pMod;             /* Pointer to the implementation of the module */
774   sqlite3_vtab *pVtab;      /* Pointer to the module instance */
775   int nModuleArg;           /* Number of arguments to the module */
776   char **azModuleArg;       /* Text of all module args. [0] is module name */
777 #endif
778   Schema *pSchema;          /* Schema that contains this table */
779 };
780 
781 /*
782 ** Test to see whether or not a table is a virtual table.  This is
783 ** done as a macro so that it will be optimized out when virtual
784 ** table support is omitted from the build.
785 */
786 #ifndef SQLITE_OMIT_VIRTUALTABLE
787 #  define IsVirtual(X)      ((X)->isVirtual)
788 #  define IsHiddenColumn(X) ((X)->isHidden)
789 #else
790 #  define IsVirtual(X)      0
791 #  define IsHiddenColumn(X) 0
792 #endif
793 
794 /*
795 ** Each foreign key constraint is an instance of the following structure.
796 **
797 ** A foreign key is associated with two tables.  The "from" table is
798 ** the table that contains the REFERENCES clause that creates the foreign
799 ** key.  The "to" table is the table that is named in the REFERENCES clause.
800 ** Consider this example:
801 **
802 **     CREATE TABLE ex1(
803 **       a INTEGER PRIMARY KEY,
804 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
805 **     );
806 **
807 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
808 **
809 ** Each REFERENCES clause generates an instance of the following structure
810 ** which is attached to the from-table.  The to-table need not exist when
811 ** the from-table is created.  The existance of the to-table is not checked
812 ** until an attempt is made to insert data into the from-table.
813 **
814 ** The sqlite.aFKey hash table stores pointers to this structure
815 ** given the name of a to-table.  For each to-table, all foreign keys
816 ** associated with that table are on a linked list using the FKey.pNextTo
817 ** field.
818 */
819 struct FKey {
820   Table *pFrom;     /* The table that constains the REFERENCES clause */
821   FKey *pNextFrom;  /* Next foreign key in pFrom */
822   char *zTo;        /* Name of table that the key points to */
823   FKey *pNextTo;    /* Next foreign key that points to zTo */
824   int nCol;         /* Number of columns in this key */
825   struct sColMap {  /* Mapping of columns in pFrom to columns in zTo */
826     int iFrom;         /* Index of column in pFrom */
827     char *zCol;        /* Name of column in zTo.  If 0 use PRIMARY KEY */
828   } *aCol;          /* One entry for each of nCol column s */
829   u8 isDeferred;    /* True if constraint checking is deferred till COMMIT */
830   u8 updateConf;    /* How to resolve conflicts that occur on UPDATE */
831   u8 deleteConf;    /* How to resolve conflicts that occur on DELETE */
832   u8 insertConf;    /* How to resolve conflicts that occur on INSERT */
833 };
834 
835 /*
836 ** SQLite supports many different ways to resolve a constraint
837 ** error.  ROLLBACK processing means that a constraint violation
838 ** causes the operation in process to fail and for the current transaction
839 ** to be rolled back.  ABORT processing means the operation in process
840 ** fails and any prior changes from that one operation are backed out,
841 ** but the transaction is not rolled back.  FAIL processing means that
842 ** the operation in progress stops and returns an error code.  But prior
843 ** changes due to the same operation are not backed out and no rollback
844 ** occurs.  IGNORE means that the particular row that caused the constraint
845 ** error is not inserted or updated.  Processing continues and no error
846 ** is returned.  REPLACE means that preexisting database rows that caused
847 ** a UNIQUE constraint violation are removed so that the new insert or
848 ** update can proceed.  Processing continues and no error is reported.
849 **
850 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
851 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
852 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
853 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
854 ** referenced table row is propagated into the row that holds the
855 ** foreign key.
856 **
857 ** The following symbolic values are used to record which type
858 ** of action to take.
859 */
860 #define OE_None     0   /* There is no constraint to check */
861 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
862 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
863 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
864 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
865 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
866 
867 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
868 #define OE_SetNull  7   /* Set the foreign key value to NULL */
869 #define OE_SetDflt  8   /* Set the foreign key value to its default */
870 #define OE_Cascade  9   /* Cascade the changes */
871 
872 #define OE_Default  99  /* Do whatever the default action is */
873 
874 
875 /*
876 ** An instance of the following structure is passed as the first
877 ** argument to sqlite3VdbeKeyCompare and is used to control the
878 ** comparison of the two index keys.
879 **
880 ** If the KeyInfo.incrKey value is true and the comparison would
881 ** otherwise be equal, then return a result as if the second key
882 ** were larger.
883 */
884 struct KeyInfo {
885   sqlite3 *db;        /* The database connection */
886   u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
887   u8 incrKey;         /* Increase 2nd key by epsilon before comparison */
888   u8 prefixIsEqual;   /* Treat a prefix as equal */
889   int nField;         /* Number of entries in aColl[] */
890   u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
891   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
892 };
893 
894 /*
895 ** Each SQL index is represented in memory by an
896 ** instance of the following structure.
897 **
898 ** The columns of the table that are to be indexed are described
899 ** by the aiColumn[] field of this structure.  For example, suppose
900 ** we have the following table and index:
901 **
902 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
903 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
904 **
905 ** In the Table structure describing Ex1, nCol==3 because there are
906 ** three columns in the table.  In the Index structure describing
907 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
908 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
909 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
910 ** The second column to be indexed (c1) has an index of 0 in
911 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
912 **
913 ** The Index.onError field determines whether or not the indexed columns
914 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
915 ** it means this is not a unique index.  Otherwise it is a unique index
916 ** and the value of Index.onError indicate the which conflict resolution
917 ** algorithm to employ whenever an attempt is made to insert a non-unique
918 ** element.
919 */
920 struct Index {
921   char *zName;     /* Name of this index */
922   int nColumn;     /* Number of columns in the table used by this index */
923   int *aiColumn;   /* Which columns are used by this index.  1st is 0 */
924   unsigned *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
925   Table *pTable;   /* The SQL table being indexed */
926   int tnum;        /* Page containing root of this index in database file */
927   u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
928   u8 autoIndex;    /* True if is automatically created (ex: by UNIQUE) */
929   char *zColAff;   /* String defining the affinity of each column */
930   Index *pNext;    /* The next index associated with the same table */
931   Schema *pSchema; /* Schema containing this index */
932   u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
933   char **azColl;   /* Array of collation sequence names for index */
934 };
935 
936 /*
937 ** Each token coming out of the lexer is an instance of
938 ** this structure.  Tokens are also used as part of an expression.
939 **
940 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
941 ** may contain random values.  Do not make any assuptions about Token.dyn
942 ** and Token.n when Token.z==0.
943 */
944 struct Token {
945   const unsigned char *z; /* Text of the token.  Not NULL-terminated! */
946   unsigned dyn  : 1;      /* True for malloced memory, false for static */
947   unsigned n    : 31;     /* Number of characters in this token */
948 };
949 
950 /*
951 ** An instance of this structure contains information needed to generate
952 ** code for a SELECT that contains aggregate functions.
953 **
954 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
955 ** pointer to this structure.  The Expr.iColumn field is the index in
956 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
957 ** code for that node.
958 **
959 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
960 ** original Select structure that describes the SELECT statement.  These
961 ** fields do not need to be freed when deallocating the AggInfo structure.
962 */
963 struct AggInfo {
964   u8 directMode;          /* Direct rendering mode means take data directly
965                           ** from source tables rather than from accumulators */
966   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
967                           ** than the source table */
968   int sortingIdx;         /* Cursor number of the sorting index */
969   ExprList *pGroupBy;     /* The group by clause */
970   int nSortingColumn;     /* Number of columns in the sorting index */
971   struct AggInfo_col {    /* For each column used in source tables */
972     Table *pTab;             /* Source table */
973     int iTable;              /* Cursor number of the source table */
974     int iColumn;             /* Column number within the source table */
975     int iSorterColumn;       /* Column number in the sorting index */
976     int iMem;                /* Memory location that acts as accumulator */
977     Expr *pExpr;             /* The original expression */
978   } *aCol;
979   int nColumn;            /* Number of used entries in aCol[] */
980   int nColumnAlloc;       /* Number of slots allocated for aCol[] */
981   int nAccumulator;       /* Number of columns that show through to the output.
982                           ** Additional columns are used only as parameters to
983                           ** aggregate functions */
984   struct AggInfo_func {   /* For each aggregate function */
985     Expr *pExpr;             /* Expression encoding the function */
986     FuncDef *pFunc;          /* The aggregate function implementation */
987     int iMem;                /* Memory location that acts as accumulator */
988     int iDistinct;           /* Ephermeral table used to enforce DISTINCT */
989   } *aFunc;
990   int nFunc;              /* Number of entries in aFunc[] */
991   int nFuncAlloc;         /* Number of slots allocated for aFunc[] */
992 };
993 
994 /*
995 ** Each node of an expression in the parse tree is an instance
996 ** of this structure.
997 **
998 ** Expr.op is the opcode.  The integer parser token codes are reused
999 ** as opcodes here.  For example, the parser defines TK_GE to be an integer
1000 ** code representing the ">=" operator.  This same integer code is reused
1001 ** to represent the greater-than-or-equal-to operator in the expression
1002 ** tree.
1003 **
1004 ** Expr.pRight and Expr.pLeft are subexpressions.  Expr.pList is a list
1005 ** of argument if the expression is a function.
1006 **
1007 ** Expr.token is the operator token for this node.  For some expressions
1008 ** that have subexpressions, Expr.token can be the complete text that gave
1009 ** rise to the Expr.  In the latter case, the token is marked as being
1010 ** a compound token.
1011 **
1012 ** An expression of the form ID or ID.ID refers to a column in a table.
1013 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
1014 ** the integer cursor number of a VDBE cursor pointing to that table and
1015 ** Expr.iColumn is the column number for the specific column.  If the
1016 ** expression is used as a result in an aggregate SELECT, then the
1017 ** value is also stored in the Expr.iAgg column in the aggregate so that
1018 ** it can be accessed after all aggregates are computed.
1019 **
1020 ** If the expression is a function, the Expr.iTable is an integer code
1021 ** representing which function.  If the expression is an unbound variable
1022 ** marker (a question mark character '?' in the original SQL) then the
1023 ** Expr.iTable holds the index number for that variable.
1024 **
1025 ** If the expression is a subquery then Expr.iColumn holds an integer
1026 ** register number containing the result of the subquery.  If the
1027 ** subquery gives a constant result, then iTable is -1.  If the subquery
1028 ** gives a different answer at different times during statement processing
1029 ** then iTable is the address of a subroutine that computes the subquery.
1030 **
1031 ** The Expr.pSelect field points to a SELECT statement.  The SELECT might
1032 ** be the right operand of an IN operator.  Or, if a scalar SELECT appears
1033 ** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
1034 ** operand.
1035 **
1036 ** If the Expr is of type OP_Column, and the table it is selecting from
1037 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
1038 ** corresponding table definition.
1039 */
1040 struct Expr {
1041   u8 op;                 /* Operation performed by this node */
1042   char affinity;         /* The affinity of the column or 0 if not a column */
1043   u16 flags;             /* Various flags.  See below */
1044   CollSeq *pColl;        /* The collation type of the column or 0 */
1045   Expr *pLeft, *pRight;  /* Left and right subnodes */
1046   ExprList *pList;       /* A list of expressions used as function arguments
1047                          ** or in "<expr> IN (<expr-list)" */
1048   Token token;           /* An operand token */
1049   Token span;            /* Complete text of the expression */
1050   int iTable, iColumn;   /* When op==TK_COLUMN, then this expr node means the
1051                          ** iColumn-th field of the iTable-th table. */
1052   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
1053   int iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
1054   int iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
1055   Select *pSelect;       /* When the expression is a sub-select.  Also the
1056                          ** right side of "<expr> IN (<select>)" */
1057   Table *pTab;           /* Table for OP_Column expressions. */
1058 /*  Schema *pSchema; */
1059 #if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
1060   int nHeight;           /* Height of the tree headed by this node */
1061 #endif
1062 };
1063 
1064 /*
1065 ** The following are the meanings of bits in the Expr.flags field.
1066 */
1067 #define EP_FromJoin     0x01  /* Originated in ON or USING clause of a join */
1068 #define EP_Agg          0x02  /* Contains one or more aggregate functions */
1069 #define EP_Resolved     0x04  /* IDs have been resolved to COLUMNs */
1070 #define EP_Error        0x08  /* Expression contains one or more errors */
1071 #define EP_Distinct     0x10  /* Aggregate function with DISTINCT keyword */
1072 #define EP_VarSelect    0x20  /* pSelect is correlated, not constant */
1073 #define EP_Dequoted     0x40  /* True if the string has been dequoted */
1074 #define EP_InfixFunc    0x80  /* True for an infix function: LIKE, GLOB, etc */
1075 #define EP_ExpCollate  0x100  /* Collating sequence specified explicitly */
1076 
1077 /*
1078 ** These macros can be used to test, set, or clear bits in the
1079 ** Expr.flags field.
1080 */
1081 #define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
1082 #define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
1083 #define ExprSetProperty(E,P)     (E)->flags|=(P)
1084 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
1085 
1086 /*
1087 ** A list of expressions.  Each expression may optionally have a
1088 ** name.  An expr/name combination can be used in several ways, such
1089 ** as the list of "expr AS ID" fields following a "SELECT" or in the
1090 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
1091 ** also be used as the argument to a function, in which case the a.zName
1092 ** field is not used.
1093 */
1094 struct ExprList {
1095   int nExpr;             /* Number of expressions on the list */
1096   int nAlloc;            /* Number of entries allocated below */
1097   int iECursor;          /* VDBE Cursor associated with this ExprList */
1098   struct ExprList_item {
1099     Expr *pExpr;           /* The list of expressions */
1100     char *zName;           /* Token associated with this expression */
1101     u8 sortOrder;          /* 1 for DESC or 0 for ASC */
1102     u8 isAgg;              /* True if this is an aggregate like count(*) */
1103     u8 done;               /* A flag to indicate when processing is finished */
1104   } *a;                  /* One entry for each expression */
1105 };
1106 
1107 /*
1108 ** An instance of this structure can hold a simple list of identifiers,
1109 ** such as the list "a,b,c" in the following statements:
1110 **
1111 **      INSERT INTO t(a,b,c) VALUES ...;
1112 **      CREATE INDEX idx ON t(a,b,c);
1113 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
1114 **
1115 ** The IdList.a.idx field is used when the IdList represents the list of
1116 ** column names after a table name in an INSERT statement.  In the statement
1117 **
1118 **     INSERT INTO t(a,b,c) ...
1119 **
1120 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
1121 */
1122 struct IdList {
1123   struct IdList_item {
1124     char *zName;      /* Name of the identifier */
1125     int idx;          /* Index in some Table.aCol[] of a column named zName */
1126   } *a;
1127   int nId;         /* Number of identifiers on the list */
1128   int nAlloc;      /* Number of entries allocated for a[] below */
1129 };
1130 
1131 /*
1132 ** The bitmask datatype defined below is used for various optimizations.
1133 **
1134 ** Changing this from a 64-bit to a 32-bit type limits the number of
1135 ** tables in a join to 32 instead of 64.  But it also reduces the size
1136 ** of the library by 738 bytes on ix86.
1137 */
1138 typedef u64 Bitmask;
1139 
1140 /*
1141 ** The following structure describes the FROM clause of a SELECT statement.
1142 ** Each table or subquery in the FROM clause is a separate element of
1143 ** the SrcList.a[] array.
1144 **
1145 ** With the addition of multiple database support, the following structure
1146 ** can also be used to describe a particular table such as the table that
1147 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
1148 ** such a table must be a simple name: ID.  But in SQLite, the table can
1149 ** now be identified by a database name, a dot, then the table name: ID.ID.
1150 **
1151 ** The jointype starts out showing the join type between the current table
1152 ** and the next table on the list.  The parser builds the list this way.
1153 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
1154 ** jointype expresses the join between the table and the previous table.
1155 */
1156 struct SrcList {
1157   i16 nSrc;        /* Number of tables or subqueries in the FROM clause */
1158   i16 nAlloc;      /* Number of entries allocated in a[] below */
1159   struct SrcList_item {
1160     char *zDatabase;  /* Name of database holding this table */
1161     char *zName;      /* Name of the table */
1162     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
1163     Table *pTab;      /* An SQL table corresponding to zName */
1164     Select *pSelect;  /* A SELECT statement used in place of a table name */
1165     u8 isPopulated;   /* Temporary table associated with SELECT is populated */
1166     u8 jointype;      /* Type of join between this able and the previous */
1167     int iCursor;      /* The VDBE cursor number used to access this table */
1168     Expr *pOn;        /* The ON clause of a join */
1169     IdList *pUsing;   /* The USING clause of a join */
1170     Bitmask colUsed;  /* Bit N (1<<N) set if column N or pTab is used */
1171   } a[1];             /* One entry for each identifier on the list */
1172 };
1173 
1174 /*
1175 ** Permitted values of the SrcList.a.jointype field
1176 */
1177 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
1178 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
1179 #define JT_NATURAL   0x0004    /* True for a "natural" join */
1180 #define JT_LEFT      0x0008    /* Left outer join */
1181 #define JT_RIGHT     0x0010    /* Right outer join */
1182 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
1183 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
1184 
1185 /*
1186 ** For each nested loop in a WHERE clause implementation, the WhereInfo
1187 ** structure contains a single instance of this structure.  This structure
1188 ** is intended to be private the the where.c module and should not be
1189 ** access or modified by other modules.
1190 **
1191 ** The pIdxInfo and pBestIdx fields are used to help pick the best
1192 ** index on a virtual table.  The pIdxInfo pointer contains indexing
1193 ** information for the i-th table in the FROM clause before reordering.
1194 ** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
1195 ** The pBestIdx pointer is a copy of pIdxInfo for the i-th table after
1196 ** FROM clause ordering.  This is a little confusing so I will repeat
1197 ** it in different words.  WhereInfo.a[i].pIdxInfo is index information
1198 ** for WhereInfo.pTabList.a[i].  WhereInfo.a[i].pBestInfo is the
1199 ** index information for the i-th loop of the join.  pBestInfo is always
1200 ** either NULL or a copy of some pIdxInfo.  So for cleanup it is
1201 ** sufficient to free all of the pIdxInfo pointers.
1202 **
1203 */
1204 struct WhereLevel {
1205   int iFrom;            /* Which entry in the FROM clause */
1206   int flags;            /* Flags associated with this level */
1207   int iMem;             /* First memory cell used by this level */
1208   int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
1209   Index *pIdx;          /* Index used.  NULL if no index */
1210   int iTabCur;          /* The VDBE cursor used to access the table */
1211   int iIdxCur;          /* The VDBE cursor used to acesss pIdx */
1212   int brk;              /* Jump here to break out of the loop */
1213   int nxt;              /* Jump here to start the next IN combination */
1214   int cont;             /* Jump here to continue with the next loop cycle */
1215   int top;              /* First instruction of interior of the loop */
1216   int op, p1, p2;       /* Opcode used to terminate the loop */
1217   int nEq;              /* Number of == or IN constraints on this loop */
1218   int nIn;              /* Number of IN operators constraining this loop */
1219   struct InLoop {
1220     int iCur;              /* The VDBE cursor used by this IN operator */
1221     int topAddr;           /* Top of the IN loop */
1222   } *aInLoop;           /* Information about each nested IN operator */
1223   sqlite3_index_info *pBestIdx;  /* Index information for this level */
1224 
1225   /* The following field is really not part of the current level.  But
1226   ** we need a place to cache index information for each table in the
1227   ** FROM clause and the WhereLevel structure is a convenient place.
1228   */
1229   sqlite3_index_info *pIdxInfo;  /* Index info for n-th source table */
1230 };
1231 
1232 /*
1233 ** The WHERE clause processing routine has two halves.  The
1234 ** first part does the start of the WHERE loop and the second
1235 ** half does the tail of the WHERE loop.  An instance of
1236 ** this structure is returned by the first half and passed
1237 ** into the second half to give some continuity.
1238 */
1239 struct WhereInfo {
1240   Parse *pParse;
1241   SrcList *pTabList;   /* List of tables in the join */
1242   int iTop;            /* The very beginning of the WHERE loop */
1243   int iContinue;       /* Jump here to continue with next record */
1244   int iBreak;          /* Jump here to break out of the loop */
1245   int nLevel;          /* Number of nested loop */
1246   sqlite3_index_info **apInfo;  /* Array of pointers to index info structures */
1247   WhereLevel a[1];     /* Information about each nest loop in the WHERE */
1248 };
1249 
1250 /*
1251 ** A NameContext defines a context in which to resolve table and column
1252 ** names.  The context consists of a list of tables (the pSrcList) field and
1253 ** a list of named expression (pEList).  The named expression list may
1254 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
1255 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
1256 ** pEList corresponds to the result set of a SELECT and is NULL for
1257 ** other statements.
1258 **
1259 ** NameContexts can be nested.  When resolving names, the inner-most
1260 ** context is searched first.  If no match is found, the next outer
1261 ** context is checked.  If there is still no match, the next context
1262 ** is checked.  This process continues until either a match is found
1263 ** or all contexts are check.  When a match is found, the nRef member of
1264 ** the context containing the match is incremented.
1265 **
1266 ** Each subquery gets a new NameContext.  The pNext field points to the
1267 ** NameContext in the parent query.  Thus the process of scanning the
1268 ** NameContext list corresponds to searching through successively outer
1269 ** subqueries looking for a match.
1270 */
1271 struct NameContext {
1272   Parse *pParse;       /* The parser */
1273   SrcList *pSrcList;   /* One or more tables used to resolve names */
1274   ExprList *pEList;    /* Optional list of named expressions */
1275   int nRef;            /* Number of names resolved by this context */
1276   int nErr;            /* Number of errors encountered while resolving names */
1277   u8 allowAgg;         /* Aggregate functions allowed here */
1278   u8 hasAgg;           /* True if aggregates are seen */
1279   u8 isCheck;          /* True if resolving names in a CHECK constraint */
1280   int nDepth;          /* Depth of subquery recursion. 1 for no recursion */
1281   AggInfo *pAggInfo;   /* Information about aggregates at this level */
1282   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
1283 };
1284 
1285 /*
1286 ** An instance of the following structure contains all information
1287 ** needed to generate code for a single SELECT statement.
1288 **
1289 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
1290 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
1291 ** limit and nOffset to the value of the offset (or 0 if there is not
1292 ** offset).  But later on, nLimit and nOffset become the memory locations
1293 ** in the VDBE that record the limit and offset counters.
1294 **
1295 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
1296 ** These addresses must be stored so that we can go back and fill in
1297 ** the P3_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
1298 ** the number of columns in P2 can be computed at the same time
1299 ** as the OP_OpenEphm instruction is coded because not
1300 ** enough information about the compound query is known at that point.
1301 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
1302 ** for the result set.  The KeyInfo for addrOpenTran[2] contains collating
1303 ** sequences for the ORDER BY clause.
1304 */
1305 struct Select {
1306   ExprList *pEList;      /* The fields of the result */
1307   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
1308   u8 isDistinct;         /* True if the DISTINCT keyword is present */
1309   u8 isResolved;         /* True once sqlite3SelectResolve() has run. */
1310   u8 isAgg;              /* True if this is an aggregate query */
1311   u8 usesEphm;           /* True if uses an OpenEphemeral opcode */
1312   u8 disallowOrderBy;    /* Do not allow an ORDER BY to be attached if TRUE */
1313   char affinity;         /* MakeRecord with this affinity for SRT_Set */
1314   SrcList *pSrc;         /* The FROM clause */
1315   Expr *pWhere;          /* The WHERE clause */
1316   ExprList *pGroupBy;    /* The GROUP BY clause */
1317   Expr *pHaving;         /* The HAVING clause */
1318   ExprList *pOrderBy;    /* The ORDER BY clause */
1319   Select *pPrior;        /* Prior select in a compound select statement */
1320   Select *pNext;         /* Next select to the left in a compound */
1321   Select *pRightmost;    /* Right-most select in a compound select statement */
1322   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
1323   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
1324   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
1325   int addrOpenEphm[3];   /* OP_OpenEphem opcodes related to this select */
1326 };
1327 
1328 /*
1329 ** The results of a select can be distributed in several ways.
1330 */
1331 #define SRT_Union        1  /* Store result as keys in an index */
1332 #define SRT_Except       2  /* Remove result from a UNION index */
1333 #define SRT_Discard      3  /* Do not save the results anywhere */
1334 
1335 /* The ORDER BY clause is ignored for all of the above */
1336 #define IgnorableOrderby(X) (X<=SRT_Discard)
1337 
1338 #define SRT_Callback     4  /* Invoke a callback with each row of result */
1339 #define SRT_Mem          5  /* Store result in a memory cell */
1340 #define SRT_Set          6  /* Store non-null results as keys in an index */
1341 #define SRT_Table        7  /* Store result as data with an automatic rowid */
1342 #define SRT_EphemTab     8  /* Create transient tab and store like SRT_Table */
1343 #define SRT_Subroutine   9  /* Call a subroutine to handle results */
1344 #define SRT_Exists      10  /* Store 1 if the result is not empty */
1345 
1346 /*
1347 ** An SQL parser context.  A copy of this structure is passed through
1348 ** the parser and down into all the parser action routine in order to
1349 ** carry around information that is global to the entire parse.
1350 **
1351 ** The structure is divided into two parts.  When the parser and code
1352 ** generate call themselves recursively, the first part of the structure
1353 ** is constant but the second part is reset at the beginning and end of
1354 ** each recursion.
1355 **
1356 ** The nTableLock and aTableLock variables are only used if the shared-cache
1357 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
1358 ** used to store the set of table-locks required by the statement being
1359 ** compiled. Function sqlite3TableLock() is used to add entries to the
1360 ** list.
1361 */
1362 struct Parse {
1363   sqlite3 *db;         /* The main database structure */
1364   int rc;              /* Return code from execution */
1365   char *zErrMsg;       /* An error message */
1366   Vdbe *pVdbe;         /* An engine for executing database bytecode */
1367   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
1368   u8 nameClash;        /* A permanent table name clashes with temp table name */
1369   u8 checkSchema;      /* Causes schema cookie check after an error */
1370   u8 nested;           /* Number of nested calls to the parser/code generator */
1371   u8 parseError;       /* True after a parsing error.  Ticket #1794 */
1372   int nErr;            /* Number of errors seen */
1373   int nTab;            /* Number of previously allocated VDBE cursors */
1374   int nMem;            /* Number of memory cells used so far */
1375   int nSet;            /* Number of sets used so far */
1376   int ckOffset;        /* Stack offset to data used by CHECK constraints */
1377   u32 writeMask;       /* Start a write transaction on these databases */
1378   u32 cookieMask;      /* Bitmask of schema verified databases */
1379   int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
1380   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
1381 #ifndef SQLITE_OMIT_SHARED_CACHE
1382   int nTableLock;        /* Number of locks in aTableLock */
1383   TableLock *aTableLock; /* Required table locks for shared-cache mode */
1384 #endif
1385 
1386   /* Above is constant between recursions.  Below is reset before and after
1387   ** each recursion */
1388 
1389   int nVar;            /* Number of '?' variables seen in the SQL so far */
1390   int nVarExpr;        /* Number of used slots in apVarExpr[] */
1391   int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
1392   Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
1393   u8 explain;          /* True if the EXPLAIN flag is found on the query */
1394   Token sErrToken;     /* The token at which the error occurred */
1395   Token sNameToken;    /* Token with unqualified schema object name */
1396   Token sLastToken;    /* The last token parsed */
1397   const char *zSql;    /* All SQL text */
1398   const char *zTail;   /* All SQL text past the last semicolon parsed */
1399   Table *pNewTable;    /* A table being constructed by CREATE TABLE */
1400   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
1401   TriggerStack *trigStack;  /* Trigger actions being coded */
1402   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
1403 #ifndef SQLITE_OMIT_VIRTUALTABLE
1404   Token sArg;                /* Complete text of a module argument */
1405   u8 declareVtab;            /* True if inside sqlite3_declare_vtab() */
1406   Table *pVirtualLock;       /* Require virtual table lock on this table */
1407 #endif
1408 #if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
1409   int nHeight;            /* Expression tree height of current sub-select */
1410 #endif
1411 };
1412 
1413 #ifdef SQLITE_OMIT_VIRTUALTABLE
1414   #define IN_DECLARE_VTAB 0
1415 #else
1416   #define IN_DECLARE_VTAB (pParse->declareVtab)
1417 #endif
1418 
1419 /*
1420 ** An instance of the following structure can be declared on a stack and used
1421 ** to save the Parse.zAuthContext value so that it can be restored later.
1422 */
1423 struct AuthContext {
1424   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
1425   Parse *pParse;              /* The Parse structure */
1426 };
1427 
1428 /*
1429 ** Bitfield flags for P2 value in OP_Insert and OP_Delete
1430 */
1431 #define OPFLAG_NCHANGE   1    /* Set to update db->nChange */
1432 #define OPFLAG_LASTROWID 2    /* Set to update db->lastRowid */
1433 #define OPFLAG_ISUPDATE  4    /* This OP_Insert is an sql UPDATE */
1434 #define OPFLAG_APPEND    8    /* This is likely to be an append */
1435 
1436 /*
1437  * Each trigger present in the database schema is stored as an instance of
1438  * struct Trigger.
1439  *
1440  * Pointers to instances of struct Trigger are stored in two ways.
1441  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
1442  *    database). This allows Trigger structures to be retrieved by name.
1443  * 2. All triggers associated with a single table form a linked list, using the
1444  *    pNext member of struct Trigger. A pointer to the first element of the
1445  *    linked list is stored as the "pTrigger" member of the associated
1446  *    struct Table.
1447  *
1448  * The "step_list" member points to the first element of a linked list
1449  * containing the SQL statements specified as the trigger program.
1450  */
1451 struct Trigger {
1452   char *name;             /* The name of the trigger                        */
1453   char *table;            /* The table or view to which the trigger applies */
1454   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
1455   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
1456   Expr *pWhen;            /* The WHEN clause of the expresion (may be NULL) */
1457   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
1458                              the <column-list> is stored here */
1459   Token nameToken;        /* Token containing zName. Use during parsing only */
1460   Schema *pSchema;        /* Schema containing the trigger */
1461   Schema *pTabSchema;     /* Schema containing the table */
1462   TriggerStep *step_list; /* Link list of trigger program steps             */
1463   Trigger *pNext;         /* Next trigger associated with the table */
1464 };
1465 
1466 /*
1467 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
1468 ** determine which.
1469 **
1470 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
1471 ** In that cases, the constants below can be ORed together.
1472 */
1473 #define TRIGGER_BEFORE  1
1474 #define TRIGGER_AFTER   2
1475 
1476 /*
1477  * An instance of struct TriggerStep is used to store a single SQL statement
1478  * that is a part of a trigger-program.
1479  *
1480  * Instances of struct TriggerStep are stored in a singly linked list (linked
1481  * using the "pNext" member) referenced by the "step_list" member of the
1482  * associated struct Trigger instance. The first element of the linked list is
1483  * the first step of the trigger-program.
1484  *
1485  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
1486  * "SELECT" statement. The meanings of the other members is determined by the
1487  * value of "op" as follows:
1488  *
1489  * (op == TK_INSERT)
1490  * orconf    -> stores the ON CONFLICT algorithm
1491  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
1492  *              this stores a pointer to the SELECT statement. Otherwise NULL.
1493  * target    -> A token holding the name of the table to insert into.
1494  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
1495  *              this stores values to be inserted. Otherwise NULL.
1496  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
1497  *              statement, then this stores the column-names to be
1498  *              inserted into.
1499  *
1500  * (op == TK_DELETE)
1501  * target    -> A token holding the name of the table to delete from.
1502  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
1503  *              Otherwise NULL.
1504  *
1505  * (op == TK_UPDATE)
1506  * target    -> A token holding the name of the table to update rows of.
1507  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
1508  *              Otherwise NULL.
1509  * pExprList -> A list of the columns to update and the expressions to update
1510  *              them to. See sqlite3Update() documentation of "pChanges"
1511  *              argument.
1512  *
1513  */
1514 struct TriggerStep {
1515   int op;              /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
1516   int orconf;          /* OE_Rollback etc. */
1517   Trigger *pTrig;      /* The trigger that this step is a part of */
1518 
1519   Select *pSelect;     /* Valid for SELECT and sometimes
1520                           INSERT steps (when pExprList == 0) */
1521   Token target;        /* Valid for DELETE, UPDATE, INSERT steps */
1522   Expr *pWhere;        /* Valid for DELETE, UPDATE steps */
1523   ExprList *pExprList; /* Valid for UPDATE statements and sometimes
1524                            INSERT steps (when pSelect == 0)         */
1525   IdList *pIdList;     /* Valid for INSERT statements only */
1526   TriggerStep *pNext;  /* Next in the link-list */
1527   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
1528 };
1529 
1530 /*
1531  * An instance of struct TriggerStack stores information required during code
1532  * generation of a single trigger program. While the trigger program is being
1533  * coded, its associated TriggerStack instance is pointed to by the
1534  * "pTriggerStack" member of the Parse structure.
1535  *
1536  * The pTab member points to the table that triggers are being coded on. The
1537  * newIdx member contains the index of the vdbe cursor that points at the temp
1538  * table that stores the new.* references. If new.* references are not valid
1539  * for the trigger being coded (for example an ON DELETE trigger), then newIdx
1540  * is set to -1. The oldIdx member is analogous to newIdx, for old.* references.
1541  *
1542  * The ON CONFLICT policy to be used for the trigger program steps is stored
1543  * as the orconf member. If this is OE_Default, then the ON CONFLICT clause
1544  * specified for individual triggers steps is used.
1545  *
1546  * struct TriggerStack has a "pNext" member, to allow linked lists to be
1547  * constructed. When coding nested triggers (triggers fired by other triggers)
1548  * each nested trigger stores its parent trigger's TriggerStack as the "pNext"
1549  * pointer. Once the nested trigger has been coded, the pNext value is restored
1550  * to the pTriggerStack member of the Parse stucture and coding of the parent
1551  * trigger continues.
1552  *
1553  * Before a nested trigger is coded, the linked list pointed to by the
1554  * pTriggerStack is scanned to ensure that the trigger is not about to be coded
1555  * recursively. If this condition is detected, the nested trigger is not coded.
1556  */
1557 struct TriggerStack {
1558   Table *pTab;         /* Table that triggers are currently being coded on */
1559   int newIdx;          /* Index of vdbe cursor to "new" temp table */
1560   int oldIdx;          /* Index of vdbe cursor to "old" temp table */
1561   int orconf;          /* Current orconf policy */
1562   int ignoreJump;      /* where to jump to for a RAISE(IGNORE) */
1563   Trigger *pTrigger;   /* The trigger currently being coded */
1564   TriggerStack *pNext; /* Next trigger down on the trigger stack */
1565 };
1566 
1567 /*
1568 ** The following structure contains information used by the sqliteFix...
1569 ** routines as they walk the parse tree to make database references
1570 ** explicit.
1571 */
1572 typedef struct DbFixer DbFixer;
1573 struct DbFixer {
1574   Parse *pParse;      /* The parsing context.  Error messages written here */
1575   const char *zDb;    /* Make sure all objects are contained in this database */
1576   const char *zType;  /* Type of the container - used for error messages */
1577   const Token *pName; /* Name of the container - used for error messages */
1578 };
1579 
1580 /*
1581 ** An objected used to accumulate the text of a string where we
1582 ** do not necessarily know how big the string will be in the end.
1583 */
1584 struct StrAccum {
1585   char *zBase;     /* A base allocation.  Not from malloc. */
1586   char *zText;     /* The string collected so far */
1587   int  nChar;      /* Length of the string so far */
1588   int  nAlloc;     /* Amount of space allocated in zText */
1589   u8   mallocFailed;   /* Becomes true if any memory allocation fails */
1590   u8   useMalloc;      /* True if zText is enlargable using realloc */
1591   u8   tooBig;         /* Becomes true if string size exceeds limits */
1592 };
1593 
1594 /*
1595 ** A pointer to this structure is used to communicate information
1596 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
1597 */
1598 typedef struct {
1599   sqlite3 *db;        /* The database being initialized */
1600   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
1601   char **pzErrMsg;    /* Error message stored here */
1602   int rc;             /* Result code stored here */
1603 } InitData;
1604 
1605 /*
1606 ** Assuming zIn points to the first byte of a UTF-8 character,
1607 ** advance zIn to point to the first byte of the next UTF-8 character.
1608 */
1609 #define SQLITE_SKIP_UTF8(zIn) {                        \
1610   if( (*(zIn++))>=0xc0 ){                              \
1611     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
1612   }                                                    \
1613 }
1614 
1615 /*
1616 ** The SQLITE_CORRUPT_BKPT macro can be either a constant (for production
1617 ** builds) or a function call (for debugging).  If it is a function call,
1618 ** it allows the operator to set a breakpoint at the spot where database
1619 ** corruption is first detected.
1620 */
1621 #ifdef SQLITE_DEBUG
1622   int sqlite3Corrupt(void);
1623 # define SQLITE_CORRUPT_BKPT sqlite3Corrupt()
1624 # define DEBUGONLY(X)        X
1625 #else
1626 # define SQLITE_CORRUPT_BKPT SQLITE_CORRUPT
1627 # define DEBUGONLY(X)
1628 #endif
1629 
1630 /*
1631 ** Internal function prototypes
1632 */
1633 int sqlite3StrICmp(const char *, const char *);
1634 int sqlite3StrNICmp(const char *, const char *, int);
1635 int sqlite3IsNumber(const char*, int*, u8);
1636 
1637 void *sqlite3MallocZero(unsigned);
1638 void *sqlite3DbMallocZero(sqlite3*, unsigned);
1639 void *sqlite3DbMallocRaw(sqlite3*, unsigned);
1640 char *sqlite3StrDup(const char*);
1641 char *sqlite3StrNDup(const char*, int);
1642 char *sqlite3DbStrDup(sqlite3*,const char*);
1643 char *sqlite3DbStrNDup(sqlite3*,const char*, int);
1644 void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
1645 void *sqlite3DbRealloc(sqlite3 *, void *, int);
1646 
1647 char *sqlite3MPrintf(sqlite3*,const char*, ...);
1648 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
1649 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
1650   void sqlite3DebugPrintf(const char*, ...);
1651 #endif
1652 #if defined(SQLITE_TEST)
1653   void *sqlite3TextToPtr(const char*);
1654 #endif
1655 void sqlite3SetString(char **, ...);
1656 void sqlite3ErrorMsg(Parse*, const char*, ...);
1657 void sqlite3ErrorClear(Parse*);
1658 void sqlite3Dequote(char*);
1659 void sqlite3DequoteExpr(sqlite3*, Expr*);
1660 int sqlite3KeywordCode(const unsigned char*, int);
1661 int sqlite3RunParser(Parse*, const char*, char **);
1662 void sqlite3FinishCoding(Parse*);
1663 Expr *sqlite3Expr(sqlite3*, int, Expr*, Expr*, const Token*);
1664 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
1665 Expr *sqlite3RegisterExpr(Parse*,Token*);
1666 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
1667 void sqlite3ExprSpan(Expr*,Token*,Token*);
1668 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
1669 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
1670 void sqlite3ExprDelete(Expr*);
1671 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*,Token*);
1672 void sqlite3ExprListDelete(ExprList*);
1673 int sqlite3Init(sqlite3*, char**);
1674 int sqlite3InitCallback(void*, int, char**, char**);
1675 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
1676 void sqlite3ResetInternalSchema(sqlite3*, int);
1677 void sqlite3BeginParse(Parse*,int);
1678 void sqlite3CommitInternalChanges(sqlite3*);
1679 Table *sqlite3ResultSetOfSelect(Parse*,char*,Select*);
1680 void sqlite3OpenMasterTable(Parse *, int);
1681 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
1682 void sqlite3AddColumn(Parse*,Token*);
1683 void sqlite3AddNotNull(Parse*, int);
1684 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
1685 void sqlite3AddCheckConstraint(Parse*, Expr*);
1686 void sqlite3AddColumnType(Parse*,Token*);
1687 void sqlite3AddDefaultValue(Parse*,Expr*);
1688 void sqlite3AddCollateType(Parse*, Token*);
1689 void sqlite3EndTable(Parse*,Token*,Token*,Select*);
1690 
1691 void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
1692 
1693 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
1694   int sqlite3ViewGetColumnNames(Parse*,Table*);
1695 #else
1696 # define sqlite3ViewGetColumnNames(A,B) 0
1697 #endif
1698 
1699 void sqlite3DropTable(Parse*, SrcList*, int, int);
1700 void sqlite3DeleteTable(Table*);
1701 void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
1702 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int,int*,int*,int*);
1703 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
1704 int sqlite3IdListIndex(IdList*,const char*);
1705 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
1706 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*, Token*,
1707                                       Select*, Expr*, IdList*);
1708 void sqlite3SrcListShiftJoinType(SrcList*);
1709 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
1710 void sqlite3IdListDelete(IdList*);
1711 void sqlite3SrcListDelete(SrcList*);
1712 void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
1713                         Token*, int, int);
1714 void sqlite3DropIndex(Parse*, SrcList*, int);
1715 int sqlite3Select(Parse*, Select*, int, int, Select*, int, int*, char *aff);
1716 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
1717                          Expr*,ExprList*,int,Expr*,Expr*);
1718 void sqlite3SelectDelete(Select*);
1719 Table *sqlite3SrcListLookup(Parse*, SrcList*);
1720 int sqlite3IsReadOnly(Parse*, Table*, int);
1721 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
1722 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
1723 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
1724 WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**);
1725 void sqlite3WhereEnd(WhereInfo*);
1726 void sqlite3ExprCodeGetColumn(Vdbe*, Table*, int, int);
1727 void sqlite3ExprCode(Parse*, Expr*);
1728 void sqlite3ExprCodeAndCache(Parse*, Expr*);
1729 int sqlite3ExprCodeExprList(Parse*, ExprList*);
1730 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
1731 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
1732 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
1733 Table *sqlite3LocateTable(Parse*,const char*, const char*);
1734 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
1735 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
1736 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
1737 void sqlite3Vacuum(Parse*);
1738 int sqlite3RunVacuum(char**, sqlite3*);
1739 char *sqlite3NameFromToken(sqlite3*, Token*);
1740 int sqlite3ExprCompare(Expr*, Expr*);
1741 int sqlite3ExprResolveNames(NameContext *, Expr *);
1742 int sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
1743 int sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
1744 Vdbe *sqlite3GetVdbe(Parse*);
1745 Expr *sqlite3CreateIdExpr(Parse *, const char*);
1746 void sqlite3Randomness(int, void*);
1747 void sqlite3RollbackAll(sqlite3*);
1748 void sqlite3CodeVerifySchema(Parse*, int);
1749 void sqlite3BeginTransaction(Parse*, int);
1750 void sqlite3CommitTransaction(Parse*);
1751 void sqlite3RollbackTransaction(Parse*);
1752 int sqlite3ExprIsConstant(Expr*);
1753 int sqlite3ExprIsConstantNotJoin(Expr*);
1754 int sqlite3ExprIsConstantOrFunction(Expr*);
1755 int sqlite3ExprIsInteger(Expr*, int*);
1756 int sqlite3IsRowid(const char*);
1757 void sqlite3GenerateRowDelete(sqlite3*, Vdbe*, Table*, int, int);
1758 void sqlite3GenerateRowIndexDelete(Vdbe*, Table*, int, char*);
1759 void sqlite3GenerateIndexKey(Vdbe*, Index*, int);
1760 void sqlite3GenerateConstraintChecks(Parse*,Table*,int,char*,int,int,int,int);
1761 void sqlite3CompleteInsertion(Parse*, Table*, int, char*, int, int, int, int);
1762 void sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
1763 void sqlite3BeginWriteOperation(Parse*, int, int);
1764 Expr *sqlite3ExprDup(sqlite3*,Expr*);
1765 void sqlite3TokenCopy(sqlite3*,Token*, Token*);
1766 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*);
1767 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*);
1768 IdList *sqlite3IdListDup(sqlite3*,IdList*);
1769 Select *sqlite3SelectDup(sqlite3*,Select*);
1770 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);
1771 void sqlite3RegisterBuiltinFunctions(sqlite3*);
1772 void sqlite3RegisterDateTimeFunctions(sqlite3*);
1773 int sqlite3SafetyOn(sqlite3*);
1774 int sqlite3SafetyOff(sqlite3*);
1775 int sqlite3SafetyCheck(sqlite3*);
1776 void sqlite3ChangeCookie(sqlite3*, Vdbe*, int);
1777 
1778 #ifndef SQLITE_OMIT_TRIGGER
1779   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
1780                            Expr*,int, int);
1781   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
1782   void sqlite3DropTrigger(Parse*, SrcList*, int);
1783   void sqlite3DropTriggerPtr(Parse*, Trigger*);
1784   int sqlite3TriggersExist(Parse*, Table*, int, ExprList*);
1785   int sqlite3CodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int,
1786                            int, int);
1787   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
1788   void sqlite3DeleteTriggerStep(TriggerStep*);
1789   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
1790   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
1791                                         ExprList*,Select*,int);
1792   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, int);
1793   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
1794   void sqlite3DeleteTrigger(Trigger*);
1795   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
1796 #else
1797 # define sqlite3TriggersExist(A,B,C,D,E,F) 0
1798 # define sqlite3DeleteTrigger(A)
1799 # define sqlite3DropTriggerPtr(A,B)
1800 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
1801 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I) 0
1802 #endif
1803 
1804 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
1805 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
1806 void sqlite3DeferForeignKey(Parse*, int);
1807 #ifndef SQLITE_OMIT_AUTHORIZATION
1808   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
1809   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
1810   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
1811   void sqlite3AuthContextPop(AuthContext*);
1812 #else
1813 # define sqlite3AuthRead(a,b,c,d)
1814 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
1815 # define sqlite3AuthContextPush(a,b,c)
1816 # define sqlite3AuthContextPop(a)  ((void)(a))
1817 #endif
1818 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
1819 void sqlite3Detach(Parse*, Expr*);
1820 int sqlite3BtreeFactory(const sqlite3 *db, const char *zFilename,
1821                        int omitJournal, int nCache, int flags, Btree **ppBtree);
1822 int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
1823 int sqlite3FixSrcList(DbFixer*, SrcList*);
1824 int sqlite3FixSelect(DbFixer*, Select*);
1825 int sqlite3FixExpr(DbFixer*, Expr*);
1826 int sqlite3FixExprList(DbFixer*, ExprList*);
1827 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
1828 int sqlite3AtoF(const char *z, double*);
1829 char *sqlite3_snprintf(int,char*,const char*,...);
1830 int sqlite3GetInt32(const char *, int*);
1831 int sqlite3FitsIn64Bits(const char *, int);
1832 int sqlite3Utf16ByteLen(const void *pData, int nChar);
1833 int sqlite3Utf8CharLen(const char *pData, int nByte);
1834 int sqlite3Utf8Read(const u8*, const u8*, const u8**);
1835 int sqlite3PutVarint(unsigned char *, u64);
1836 int sqlite3GetVarint(const unsigned char *, u64 *);
1837 int sqlite3GetVarint32(const unsigned char *, u32 *);
1838 int sqlite3VarintLen(u64 v);
1839 void sqlite3IndexAffinityStr(Vdbe *, Index *);
1840 void sqlite3TableAffinityStr(Vdbe *, Table *);
1841 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
1842 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
1843 char sqlite3ExprAffinity(Expr *pExpr);
1844 int sqlite3Atoi64(const char*, i64*);
1845 void sqlite3Error(sqlite3*, int, const char*,...);
1846 void *sqlite3HexToBlob(sqlite3*, const char *z);
1847 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
1848 const char *sqlite3ErrStr(int);
1849 int sqlite3ReadSchema(Parse *pParse);
1850 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char *,int,int);
1851 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName, int nName);
1852 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
1853 Expr *sqlite3ExprSetColl(Parse *pParse, Expr *, Token *);
1854 int sqlite3CheckCollSeq(Parse *, CollSeq *);
1855 int sqlite3CheckObjectName(Parse *, const char *);
1856 void sqlite3VdbeSetChanges(sqlite3 *, int);
1857 
1858 const void *sqlite3ValueText(sqlite3_value*, u8);
1859 int sqlite3ValueBytes(sqlite3_value*, u8);
1860 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
1861                         void(*)(void*));
1862 void sqlite3ValueFree(sqlite3_value*);
1863 sqlite3_value *sqlite3ValueNew(sqlite3 *);
1864 char *sqlite3Utf16to8(sqlite3 *, const void*, int);
1865 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
1866 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
1867 #ifndef SQLITE_AMALGAMATION
1868 extern const unsigned char sqlite3UpperToLower[];
1869 #endif
1870 void sqlite3RootPageMoved(Db*, int, int);
1871 void sqlite3Reindex(Parse*, Token*, Token*);
1872 void sqlite3AlterFunctions(sqlite3*);
1873 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
1874 int sqlite3GetToken(const unsigned char *, int *);
1875 void sqlite3NestedParse(Parse*, const char*, ...);
1876 void sqlite3ExpirePreparedStatements(sqlite3*);
1877 void sqlite3CodeSubselect(Parse *, Expr *);
1878 int sqlite3SelectResolve(Parse *, Select *, NameContext *);
1879 void sqlite3ColumnDefault(Vdbe *, Table *, int);
1880 void sqlite3AlterFinishAddColumn(Parse *, Token *);
1881 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
1882 CollSeq *sqlite3GetCollSeq(sqlite3*, CollSeq *, const char *, int);
1883 char sqlite3AffinityType(const Token*);
1884 void sqlite3Analyze(Parse*, Token*, Token*);
1885 int sqlite3InvokeBusyHandler(BusyHandler*);
1886 int sqlite3FindDb(sqlite3*, Token*);
1887 int sqlite3AnalysisLoad(sqlite3*,int iDB);
1888 void sqlite3DefaultRowEst(Index*);
1889 void sqlite3RegisterLikeFunctions(sqlite3*, int);
1890 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
1891 void sqlite3AttachFunctions(sqlite3 *);
1892 void sqlite3MinimumFileFormat(Parse*, int, int);
1893 void sqlite3SchemaFree(void *);
1894 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
1895 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
1896 KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
1897 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
1898   void (*)(sqlite3_context*,int,sqlite3_value **),
1899   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*));
1900 int sqlite3ApiExit(sqlite3 *db, int);
1901 int sqlite3OpenTempDatabase(Parse *);
1902 
1903 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
1904 char *sqlite3StrAccumFinish(StrAccum*);
1905 void sqlite3StrAccumReset(StrAccum*);
1906 
1907 
1908 /*
1909 ** The interface to the LEMON-generated parser
1910 */
1911 void *sqlite3ParserAlloc(void*(*)(size_t));
1912 void sqlite3ParserFree(void*, void(*)(void*));
1913 void sqlite3Parser(void*, int, Token, Parse*);
1914 
1915 #ifndef SQLITE_OMIT_LOAD_EXTENSION
1916   void sqlite3CloseExtensions(sqlite3*);
1917   int sqlite3AutoLoadExtensions(sqlite3*);
1918 #else
1919 # define sqlite3CloseExtensions(X)
1920 # define sqlite3AutoLoadExtensions(X)  SQLITE_OK
1921 #endif
1922 
1923 #ifndef SQLITE_OMIT_SHARED_CACHE
1924   void sqlite3TableLock(Parse *, int, int, u8, const char *);
1925 #else
1926   #define sqlite3TableLock(v,w,x,y,z)
1927 #endif
1928 
1929 #ifdef SQLITE_TEST
1930   int sqlite3Utf8To8(unsigned char*);
1931 #endif
1932 
1933 /*
1934 ** The MallocDisallow() and MallocAllow() routines are like asserts.
1935 ** Call them around a section of code that you do not expect to do
1936 ** any memory allocation.
1937 */
1938 #ifdef SQLITE_MEMDEBUG
1939   void sqlite3MallocDisallow(void);
1940   void sqlite3MallocAllow(void);
1941   void sqlite3MallocBenignFailure(int);
1942   void sqlite3MallocEnterBenignBlock(int isBenign);
1943   void sqlite3MallocLeaveBenignBlock();
1944 #else
1945 # define sqlite3MallocDisallow()
1946 # define sqlite3MallocAllow()
1947 # define sqlite3MallocBenignFailure(x)
1948 # define sqlite3MallocEnterBenignBlock(x);
1949 # define sqlite3MallocLeaveBenignBlock();
1950 #endif
1951 
1952 
1953 #ifdef SQLITE_OMIT_VIRTUALTABLE
1954 #  define sqlite3VtabClear(X)
1955 #  define sqlite3VtabSync(X,Y) (Y)
1956 #  define sqlite3VtabRollback(X)
1957 #  define sqlite3VtabCommit(X)
1958 #else
1959    void sqlite3VtabClear(Table*);
1960    int sqlite3VtabSync(sqlite3 *db, int rc);
1961    int sqlite3VtabRollback(sqlite3 *db);
1962    int sqlite3VtabCommit(sqlite3 *db);
1963 #endif
1964 void sqlite3VtabLock(sqlite3_vtab*);
1965 void sqlite3VtabUnlock(sqlite3*, sqlite3_vtab*);
1966 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*);
1967 void sqlite3VtabFinishParse(Parse*, Token*);
1968 void sqlite3VtabArgInit(Parse*);
1969 void sqlite3VtabArgExtend(Parse*, Token*);
1970 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
1971 int sqlite3VtabCallConnect(Parse*, Table*);
1972 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
1973 int sqlite3VtabBegin(sqlite3 *, sqlite3_vtab *);
1974 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
1975 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
1976 int sqlite3Reprepare(Vdbe*);
1977 void sqlite3ExprListCheckLength(Parse*, ExprList*, int, const char*);
1978 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
1979 
1980 #define IN_INDEX_ROWID           1
1981 #define IN_INDEX_EPH             2
1982 #define IN_INDEX_INDEX           3
1983 int sqlite3FindInIndex(Parse *, Expr *, int);
1984 
1985 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
1986   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
1987   int sqlite3JournalSize(sqlite3_vfs *);
1988   int sqlite3JournalCreate(sqlite3_file *);
1989 #else
1990   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
1991 #endif
1992 
1993 #if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
1994   void sqlite3ExprSetHeight(Expr *);
1995   int sqlite3SelectExprHeight(Select *);
1996 #else
1997   #define sqlite3ExprSetHeight(x)
1998 #endif
1999 
2000 u32 sqlite3Get4byte(const u8*);
2001 void sqlite3Put4byte(u8*, u32);
2002 
2003 #ifdef SQLITE_SSE
2004 #include "sseInt.h"
2005 #endif
2006 
2007 #ifdef SQLITE_DEBUG
2008   void sqlite3ParserTrace(FILE*, char *);
2009 #endif
2010 
2011 /*
2012 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
2013 ** sqlite3_io_trace is a pointer to a printf-like routine used to
2014 ** print I/O tracing messages.
2015 */
2016 #ifdef SQLITE_ENABLE_IOTRACE
2017 # define IOTRACE(A)  if( sqlite3_io_trace ){ sqlite3_io_trace A; }
2018   void sqlite3VdbeIOTraceSql(Vdbe*);
2019 #else
2020 # define IOTRACE(A)
2021 # define sqlite3VdbeIOTraceSql(X)
2022 #endif
2023 SQLITE_EXTERN void (*sqlite3_io_trace)(const char*,...);
2024 
2025 #endif
2026