xref: /sqlite-3.40.0/src/sqliteInt.h (revision 8a29dfde)
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 1.691 2008/04/10 16:47:42 drh Exp $
15 */
16 #ifndef _SQLITEINT_H_
17 #define _SQLITEINT_H_
18 
19 /*
20 ** Include the configuration header output by 'configure' if it was run
21 ** (otherwise we get an empty default).
22 */
23 #include "config.h"
24 #include "sqliteLimit.h"
25 
26 /* Disable nuisance warnings on Borland compilers */
27 #if defined(__BORLANDC__)
28 #pragma warn -rch /* unreachable code */
29 #pragma warn -ccc /* Condition is always true or false */
30 #pragma warn -aus /* Assigned value is never used */
31 #pragma warn -csu /* Comparing signed and unsigned */
32 #pragma warn -spa /* Suspicous pointer arithmetic */
33 #endif
34 
35 /* Needed for various definitions... */
36 #define _GNU_SOURCE
37 
38 /*
39 ** Include standard header files as necessary
40 */
41 #ifdef HAVE_STDINT_H
42 #include <stdint.h>
43 #endif
44 #ifdef HAVE_INTTYPES_H
45 #include <inttypes.h>
46 #endif
47 
48 /*
49 ** If possible, use the C99 intptr_t type to define an integral type of
50 ** equivalent size to a pointer.  (Technically it's >= sizeof(void *), but
51 ** practically it's == sizeof(void *)).  We fall back to an int if this type
52 ** isn't defined.
53 */
54 #ifdef HAVE_INTPTR_T
55   typedef intptr_t sqlite3_intptr_t;
56 #else
57   typedef int sqlite3_intptr_t;
58 #endif
59 
60 /*
61 ** A macro used to aid in coverage testing.  When doing coverage
62 ** testing, the condition inside the argument must be evaluated
63 ** both true and false in order to get full branch coverage.
64 ** This macro can be inserted to ensure adequate test coverage
65 ** in places where simple condition/decision coverage is inadequate.
66 */
67 #ifdef SQLITE_COVERAGE_TEST
68   void sqlite3Coverage(int);
69 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
70 #else
71 # define testcase(X)
72 #endif
73 
74 
75 /*
76 ** The macro unlikely() is a hint that surrounds a boolean
77 ** expression that is usually false.  Macro likely() surrounds
78 ** a boolean expression that is usually true.  GCC is able to
79 ** use these hints to generate better code, sometimes.
80 */
81 #if defined(__GNUC__) && 0
82 # define likely(X)    __builtin_expect((X),1)
83 # define unlikely(X)  __builtin_expect((X),0)
84 #else
85 # define likely(X)    !!(X)
86 # define unlikely(X)  !!(X)
87 #endif
88 
89 
90 /*
91 ** These #defines should enable >2GB file support on Posix if the
92 ** underlying operating system supports it.  If the OS lacks
93 ** large file support, or if the OS is windows, these should be no-ops.
94 **
95 ** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
96 ** system #includes.  Hence, this block of code must be the very first
97 ** code in all source files.
98 **
99 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
100 ** on the compiler command line.  This is necessary if you are compiling
101 ** on a recent machine (ex: RedHat 7.2) but you want your code to work
102 ** on an older machine (ex: RedHat 6.0).  If you compile on RedHat 7.2
103 ** without this option, LFS is enable.  But LFS does not exist in the kernel
104 ** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
105 ** portability you should omit LFS.
106 **
107 ** Similar is true for MacOS.  LFS is only supported on MacOS 9 and later.
108 */
109 #ifndef SQLITE_DISABLE_LFS
110 # define _LARGE_FILE       1
111 # ifndef _FILE_OFFSET_BITS
112 #   define _FILE_OFFSET_BITS 64
113 # endif
114 # define _LARGEFILE_SOURCE 1
115 #endif
116 
117 
118 /*
119 ** The SQLITE_THREADSAFE macro must be defined as either 0 or 1.
120 ** Older versions of SQLite used an optional THREADSAFE macro.
121 ** We support that for legacy
122 */
123 #if !defined(SQLITE_THREADSAFE)
124 #if defined(THREADSAFE)
125 # define SQLITE_THREADSAFE THREADSAFE
126 #else
127 # define SQLITE_THREADSAFE 1
128 #endif
129 #endif
130 
131 /*
132 ** Exactly one of the following macros must be defined in order to
133 ** specify which memory allocation subsystem to use.
134 **
135 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
136 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
137 **     SQLITE_MEMORY_SIZE            // internal allocator #1
138 **     SQLITE_MMAP_HEAP_SIZE         // internal mmap() allocator
139 **     SQLITE_POW2_MEMORY_SIZE       // internal power-of-two allocator
140 **
141 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
142 ** the default.
143 */
144 #if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_MEMDEBUG)+\
145     defined(SQLITE_MEMORY_SIZE)+defined(SQLITE_MMAP_HEAP_SIZE)+\
146     defined(SQLITE_POW2_MEMORY_SIZE)>1
147 # error "At most one of the following compile-time configuration options\
148  is allows: SQLITE_SYSTEM_MALLOC, SQLITE_MEMDEBUG, SQLITE_MEMORY_SIZE,\
149  SQLITE_MMAP_HEAP_SIZE, SQLITE_POW2_MEMORY_SIZE"
150 #endif
151 #if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_MEMDEBUG)+\
152     defined(SQLITE_MEMORY_SIZE)+defined(SQLITE_MMAP_HEAP_SIZE)+\
153     defined(SQLITE_POW2_MEMORY_SIZE)==0
154 # define SQLITE_SYSTEM_MALLOC 1
155 #endif
156 
157 /*
158 ** If SQLITE_MALLOC_SOFT_LIMIT is defined, then try to keep the
159 ** sizes of memory allocations below this value where possible.
160 */
161 #if defined(SQLITE_POW2_MEMORY_SIZE) && !defined(SQLITE_MALLOC_SOFT_LIMIT)
162 # define SQLITE_MALLOC_SOFT_LIMIT 1024
163 #endif
164 
165 /*
166 ** We need to define _XOPEN_SOURCE as follows in order to enable
167 ** recursive mutexes on most unix systems.  But Mac OS X is different.
168 ** The _XOPEN_SOURCE define causes problems for Mac OS X we are told,
169 ** so it is omitted there.  See ticket #2673.
170 **
171 ** Later we learn that _XOPEN_SOURCE is poorly or incorrectly
172 ** implemented on some systems.  So we avoid defining it at all
173 ** if it is already defined or if it is unneeded because we are
174 ** not doing a threadsafe build.  Ticket #2681.
175 **
176 ** See also ticket #2741.
177 */
178 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE
179 #  define _XOPEN_SOURCE 500  /* Needed to enable pthread recursive mutexes */
180 #endif
181 
182 #if defined(SQLITE_TCL) || defined(TCLSH)
183 # include <tcl.h>
184 #endif
185 
186 /*
187 ** Many people are failing to set -DNDEBUG=1 when compiling SQLite.
188 ** Setting NDEBUG makes the code smaller and run faster.  So the following
189 ** lines are added to automatically set NDEBUG unless the -DSQLITE_DEBUG=1
190 ** option is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
191 ** feature.
192 */
193 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
194 # define NDEBUG 1
195 #endif
196 
197 #include "sqlite3.h"
198 #include "hash.h"
199 #include "parse.h"
200 #include <stdio.h>
201 #include <stdlib.h>
202 #include <string.h>
203 #include <assert.h>
204 #include <stddef.h>
205 
206 #define sqlite3_isnan(X)  ((X)!=(X))
207 
208 /*
209 ** If compiling for a processor that lacks floating point support,
210 ** substitute integer for floating-point
211 */
212 #ifdef SQLITE_OMIT_FLOATING_POINT
213 # define double sqlite_int64
214 # define LONGDOUBLE_TYPE sqlite_int64
215 # ifndef SQLITE_BIG_DBL
216 #   define SQLITE_BIG_DBL (0x7fffffffffffffff)
217 # endif
218 # define SQLITE_OMIT_DATETIME_FUNCS 1
219 # define SQLITE_OMIT_TRACE 1
220 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
221 #endif
222 #ifndef SQLITE_BIG_DBL
223 # define SQLITE_BIG_DBL (1e99)
224 #endif
225 
226 /*
227 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
228 ** afterward. Having this macro allows us to cause the C compiler
229 ** to omit code used by TEMP tables without messy #ifndef statements.
230 */
231 #ifdef SQLITE_OMIT_TEMPDB
232 #define OMIT_TEMPDB 1
233 #else
234 #define OMIT_TEMPDB 0
235 #endif
236 
237 /*
238 ** If the following macro is set to 1, then NULL values are considered
239 ** distinct when determining whether or not two entries are the same
240 ** in a UNIQUE index.  This is the way PostgreSQL, Oracle, DB2, MySQL,
241 ** OCELOT, and Firebird all work.  The SQL92 spec explicitly says this
242 ** is the way things are suppose to work.
243 **
244 ** If the following macro is set to 0, the NULLs are indistinct for
245 ** a UNIQUE index.  In this mode, you can only have a single NULL entry
246 ** for a column declared UNIQUE.  This is the way Informix and SQL Server
247 ** work.
248 */
249 #define NULL_DISTINCT_FOR_UNIQUE 1
250 
251 /*
252 ** The "file format" number is an integer that is incremented whenever
253 ** the VDBE-level file format changes.  The following macros define the
254 ** the default file format for new databases and the maximum file format
255 ** that the library can read.
256 */
257 #define SQLITE_MAX_FILE_FORMAT 4
258 #ifndef SQLITE_DEFAULT_FILE_FORMAT
259 # define SQLITE_DEFAULT_FILE_FORMAT 1
260 #endif
261 
262 /*
263 ** Provide a default value for TEMP_STORE in case it is not specified
264 ** on the command-line
265 */
266 #ifndef TEMP_STORE
267 # define TEMP_STORE 1
268 #endif
269 
270 /*
271 ** GCC does not define the offsetof() macro so we'll have to do it
272 ** ourselves.
273 */
274 #ifndef offsetof
275 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
276 #endif
277 
278 /*
279 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
280 ** not, there are still machines out there that use EBCDIC.)
281 */
282 #if 'A' == '\301'
283 # define SQLITE_EBCDIC 1
284 #else
285 # define SQLITE_ASCII 1
286 #endif
287 
288 /*
289 ** Integers of known sizes.  These typedefs might change for architectures
290 ** where the sizes very.  Preprocessor macros are available so that the
291 ** types can be conveniently redefined at compile-type.  Like this:
292 **
293 **         cc '-DUINTPTR_TYPE=long long int' ...
294 */
295 #ifndef UINT32_TYPE
296 # ifdef HAVE_UINT32_T
297 #  define UINT32_TYPE uint32_t
298 # else
299 #  define UINT32_TYPE unsigned int
300 # endif
301 #endif
302 #ifndef UINT16_TYPE
303 # ifdef HAVE_UINT16_T
304 #  define UINT16_TYPE uint16_t
305 # else
306 #  define UINT16_TYPE unsigned short int
307 # endif
308 #endif
309 #ifndef INT16_TYPE
310 # ifdef HAVE_INT16_T
311 #  define INT16_TYPE int16_t
312 # else
313 #  define INT16_TYPE short int
314 # endif
315 #endif
316 #ifndef UINT8_TYPE
317 # ifdef HAVE_UINT8_T
318 #  define UINT8_TYPE uint8_t
319 # else
320 #  define UINT8_TYPE unsigned char
321 # endif
322 #endif
323 #ifndef INT8_TYPE
324 # ifdef HAVE_INT8_T
325 #  define INT8_TYPE int8_t
326 # else
327 #  define INT8_TYPE signed char
328 # endif
329 #endif
330 #ifndef LONGDOUBLE_TYPE
331 # define LONGDOUBLE_TYPE long double
332 #endif
333 typedef sqlite_int64 i64;          /* 8-byte signed integer */
334 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
335 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
336 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
337 typedef INT16_TYPE i16;            /* 2-byte signed integer */
338 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
339 typedef UINT8_TYPE i8;             /* 1-byte signed integer */
340 
341 /*
342 ** Macros to determine whether the machine is big or little endian,
343 ** evaluated at runtime.
344 */
345 #ifdef SQLITE_AMALGAMATION
346 const int sqlite3one;
347 #else
348 extern const int sqlite3one;
349 #endif
350 #if defined(i386) || defined(__i386__) || defined(_M_IX86)
351 # define SQLITE_BIGENDIAN    0
352 # define SQLITE_LITTLEENDIAN 1
353 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
354 #else
355 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
356 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
357 # define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
358 #endif
359 
360 /*
361 ** An instance of the following structure is used to store the busy-handler
362 ** callback for a given sqlite handle.
363 **
364 ** The sqlite.busyHandler member of the sqlite struct contains the busy
365 ** callback for the database handle. Each pager opened via the sqlite
366 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
367 ** callback is currently invoked only from within pager.c.
368 */
369 typedef struct BusyHandler BusyHandler;
370 struct BusyHandler {
371   int (*xFunc)(void *,int);  /* The busy callback */
372   void *pArg;                /* First arg to busy callback */
373   int nBusy;                 /* Incremented with each busy call */
374 };
375 
376 /*
377 ** Name of the master database table.  The master database table
378 ** is a special table that holds the names and attributes of all
379 ** user tables and indices.
380 */
381 #define MASTER_NAME       "sqlite_master"
382 #define TEMP_MASTER_NAME  "sqlite_temp_master"
383 
384 /*
385 ** The root-page of the master database table.
386 */
387 #define MASTER_ROOT       1
388 
389 /*
390 ** The name of the schema table.
391 */
392 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
393 
394 /*
395 ** A convenience macro that returns the number of elements in
396 ** an array.
397 */
398 #define ArraySize(X)    (sizeof(X)/sizeof(X[0]))
399 
400 /*
401 ** Forward references to structures
402 */
403 typedef struct AggInfo AggInfo;
404 typedef struct AuthContext AuthContext;
405 typedef struct Bitvec Bitvec;
406 typedef struct CollSeq CollSeq;
407 typedef struct Column Column;
408 typedef struct Db Db;
409 typedef struct Schema Schema;
410 typedef struct Expr Expr;
411 typedef struct ExprList ExprList;
412 typedef struct FKey FKey;
413 typedef struct FuncDef FuncDef;
414 typedef struct IdList IdList;
415 typedef struct Index Index;
416 typedef struct KeyClass KeyClass;
417 typedef struct KeyInfo KeyInfo;
418 typedef struct Module Module;
419 typedef struct NameContext NameContext;
420 typedef struct Parse Parse;
421 typedef struct Select Select;
422 typedef struct SrcList SrcList;
423 typedef struct StrAccum StrAccum;
424 typedef struct Table Table;
425 typedef struct TableLock TableLock;
426 typedef struct Token Token;
427 typedef struct TriggerStack TriggerStack;
428 typedef struct TriggerStep TriggerStep;
429 typedef struct Trigger Trigger;
430 typedef struct WhereInfo WhereInfo;
431 typedef struct WhereLevel WhereLevel;
432 
433 /*
434 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
435 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
436 ** pointer types (i.e. FuncDef) defined above.
437 */
438 #include "btree.h"
439 #include "vdbe.h"
440 #include "pager.h"
441 
442 #include "os.h"
443 #include "mutex.h"
444 
445 
446 /*
447 ** Each database file to be accessed by the system is an instance
448 ** of the following structure.  There are normally two of these structures
449 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
450 ** aDb[1] is the database file used to hold temporary tables.  Additional
451 ** databases may be attached.
452 */
453 struct Db {
454   char *zName;         /* Name of this database */
455   Btree *pBt;          /* The B*Tree structure for this database file */
456   u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
457   u8 safety_level;     /* How aggressive at synching data to disk */
458   void *pAux;               /* Auxiliary data.  Usually NULL */
459   void (*xFreeAux)(void*);  /* Routine to free pAux */
460   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
461 };
462 
463 /*
464 ** An instance of the following structure stores a database schema.
465 **
466 ** If there are no virtual tables configured in this schema, the
467 ** Schema.db variable is set to NULL. After the first virtual table
468 ** has been added, it is set to point to the database connection
469 ** used to create the connection. Once a virtual table has been
470 ** added to the Schema structure and the Schema.db variable populated,
471 ** only that database connection may use the Schema to prepare
472 ** statements.
473 */
474 struct Schema {
475   int schema_cookie;   /* Database schema version number for this file */
476   Hash tblHash;        /* All tables indexed by name */
477   Hash idxHash;        /* All (named) indices indexed by name */
478   Hash trigHash;       /* All triggers indexed by name */
479   Hash aFKey;          /* Foreign keys indexed by to-table */
480   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
481   u8 file_format;      /* Schema format version for this file */
482   u8 enc;              /* Text encoding used by this database */
483   u16 flags;           /* Flags associated with this schema */
484   int cache_size;      /* Number of pages to use in the cache */
485 #ifndef SQLITE_OMIT_VIRTUALTABLE
486   sqlite3 *db;         /* "Owner" connection. See comment above */
487 #endif
488 };
489 
490 /*
491 ** These macros can be used to test, set, or clear bits in the
492 ** Db.flags field.
493 */
494 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->flags&(P))==(P))
495 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->flags&(P))!=0)
496 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->flags|=(P)
497 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->flags&=~(P)
498 
499 /*
500 ** Allowed values for the DB.flags field.
501 **
502 ** The DB_SchemaLoaded flag is set after the database schema has been
503 ** read into internal hash tables.
504 **
505 ** DB_UnresetViews means that one or more views have column names that
506 ** have been filled out.  If the schema changes, these column names might
507 ** changes and so the view will need to be reset.
508 */
509 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
510 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
511 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
512 
513 /*
514 ** The number of different kinds of things that can be limited
515 ** using the sqlite3_limit() interface.
516 */
517 #define SQLITE_N_LIMIT (SQLITE_LIMIT_VARIABLE_NUMBER+1)
518 
519 /*
520 ** Each database is an instance of the following structure.
521 **
522 ** The sqlite.lastRowid records the last insert rowid generated by an
523 ** insert statement.  Inserts on views do not affect its value.  Each
524 ** trigger has its own context, so that lastRowid can be updated inside
525 ** triggers as usual.  The previous value will be restored once the trigger
526 ** exits.  Upon entering a before or instead of trigger, lastRowid is no
527 ** longer (since after version 2.8.12) reset to -1.
528 **
529 ** The sqlite.nChange does not count changes within triggers and keeps no
530 ** context.  It is reset at start of sqlite3_exec.
531 ** The sqlite.lsChange represents the number of changes made by the last
532 ** insert, update, or delete statement.  It remains constant throughout the
533 ** length of a statement and is then updated by OP_SetCounts.  It keeps a
534 ** context stack just like lastRowid so that the count of changes
535 ** within a trigger is not seen outside the trigger.  Changes to views do not
536 ** affect the value of lsChange.
537 ** The sqlite.csChange keeps track of the number of current changes (since
538 ** the last statement) and is used to update sqlite_lsChange.
539 **
540 ** The member variables sqlite.errCode, sqlite.zErrMsg and sqlite.zErrMsg16
541 ** store the most recent error code and, if applicable, string. The
542 ** internal function sqlite3Error() is used to set these variables
543 ** consistently.
544 */
545 struct sqlite3 {
546   sqlite3_vfs *pVfs;            /* OS Interface */
547   int nDb;                      /* Number of backends currently in use */
548   Db *aDb;                      /* All backends */
549   int flags;                    /* Miscellanous flags. See below */
550   int openFlags;                /* Flags passed to sqlite3_vfs.xOpen() */
551   int errCode;                  /* Most recent error code (SQLITE_*) */
552   int errMask;                  /* & result codes with this before returning */
553   u8 autoCommit;                /* The auto-commit flag. */
554   u8 temp_store;                /* 1: file 2: memory 0: default */
555   u8 mallocFailed;              /* True if we have seen a malloc failure */
556   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
557   int nextPagesize;             /* Pagesize after VACUUM if >0 */
558   int nTable;                   /* Number of tables in the database */
559   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
560   i64 lastRowid;                /* ROWID of most recent insert (see above) */
561   i64 priorNewRowid;            /* Last randomly generated ROWID */
562   int magic;                    /* Magic number for detect library misuse */
563   int nChange;                  /* Value returned by sqlite3_changes() */
564   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
565   sqlite3_mutex *mutex;         /* Connection mutex */
566   int aLimit[SQLITE_N_LIMIT];   /* Limits */
567   struct sqlite3InitInfo {      /* Information used during initialization */
568     int iDb;                    /* When back is being initialized */
569     int newTnum;                /* Rootpage of table being initialized */
570     u8 busy;                    /* TRUE if currently initializing */
571   } init;
572   int nExtension;               /* Number of loaded extensions */
573   void **aExtension;            /* Array of shared libraray handles */
574   struct Vdbe *pVdbe;           /* List of active virtual machines */
575   int activeVdbeCnt;            /* Number of vdbes currently executing */
576   void (*xTrace)(void*,const char*);        /* Trace function */
577   void *pTraceArg;                          /* Argument to the trace function */
578   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
579   void *pProfileArg;                        /* Argument to profile function */
580   void *pCommitArg;                 /* Argument to xCommitCallback() */
581   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
582   void *pRollbackArg;               /* Argument to xRollbackCallback() */
583   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
584   void *pUpdateArg;
585   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
586   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
587   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
588   void *pCollNeededArg;
589   sqlite3_value *pErr;          /* Most recent error message */
590   char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
591   char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
592   union {
593     int isInterrupted;          /* True if sqlite3_interrupt has been called */
594     double notUsed1;            /* Spacer */
595   } u1;
596 #ifndef SQLITE_OMIT_AUTHORIZATION
597   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
598                                 /* Access authorization function */
599   void *pAuthArg;               /* 1st argument to the access auth function */
600 #endif
601 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
602   int (*xProgress)(void *);     /* The progress callback */
603   void *pProgressArg;           /* Argument to the progress callback */
604   int nProgressOps;             /* Number of opcodes for progress callback */
605 #endif
606 #ifndef SQLITE_OMIT_VIRTUALTABLE
607   Hash aModule;                 /* populated by sqlite3_create_module() */
608   Table *pVTab;                 /* vtab with active Connect/Create method */
609   sqlite3_vtab **aVTrans;       /* Virtual tables with open transactions */
610   int nVTrans;                  /* Allocated size of aVTrans */
611 #endif
612   Hash aFunc;                   /* All functions that can be in SQL exprs */
613   Hash aCollSeq;                /* All collating sequences */
614   BusyHandler busyHandler;      /* Busy callback */
615   int busyTimeout;              /* Busy handler timeout, in msec */
616   Db aDbStatic[2];              /* Static space for the 2 default backends */
617 #ifdef SQLITE_SSE
618   sqlite3_stmt *pFetch;         /* Used by SSE to fetch stored statements */
619 #endif
620   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
621 };
622 
623 /*
624 ** A macro to discover the encoding of a database.
625 */
626 #define ENC(db) ((db)->aDb[0].pSchema->enc)
627 
628 /*
629 ** Possible values for the sqlite.flags and or Db.flags fields.
630 **
631 ** On sqlite.flags, the SQLITE_InTrans value means that we have
632 ** executed a BEGIN.  On Db.flags, SQLITE_InTrans means a statement
633 ** transaction is active on that particular database file.
634 */
635 #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
636 #define SQLITE_InTrans        0x00000008  /* True if in a transaction */
637 #define SQLITE_InternChanges  0x00000010  /* Uncommitted Hash table changes */
638 #define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
639 #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
640 #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
641                                           /*   DELETE, or UPDATE and return */
642                                           /*   the count using a callback. */
643 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
644                                           /*   result set is empty */
645 #define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
646 #define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
647 #define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
648 #define SQLITE_NoReadlock     0x00001000  /* Readlocks are omitted when
649                                           ** accessing read-only databases */
650 #define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
651 #define SQLITE_ReadUncommitted 0x00004000 /* For shared-cache mode */
652 #define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
653 #define SQLITE_FullFSync      0x00010000  /* Use full fsync on the backend */
654 #define SQLITE_LoadExtension  0x00020000  /* Enable load_extension */
655 
656 #define SQLITE_RecoveryMode   0x00040000  /* Ignore schema errors */
657 #define SQLITE_SharedCache    0x00080000  /* Cache sharing is enabled */
658 #define SQLITE_Vtab           0x00100000  /* There exists a virtual table */
659 
660 /*
661 ** Possible values for the sqlite.magic field.
662 ** The numbers are obtained at random and have no special meaning, other
663 ** than being distinct from one another.
664 */
665 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
666 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
667 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
668 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
669 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
670 
671 /*
672 ** Each SQL function is defined by an instance of the following
673 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
674 ** hash table.  When multiple functions have the same name, the hash table
675 ** points to a linked list of these structures.
676 */
677 struct FuncDef {
678   i16 nArg;            /* Number of arguments.  -1 means unlimited */
679   u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
680   u8 needCollSeq;      /* True if sqlite3GetFuncCollSeq() might be called */
681   u8 flags;            /* Some combination of SQLITE_FUNC_* */
682   void *pUserData;     /* User data parameter */
683   FuncDef *pNext;      /* Next function with same name */
684   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
685   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
686   void (*xFinalize)(sqlite3_context*);                /* Aggregate finializer */
687   char zName[1];       /* SQL name of the function.  MUST BE LAST */
688 };
689 
690 /*
691 ** Each SQLite module (virtual table definition) is defined by an
692 ** instance of the following structure, stored in the sqlite3.aModule
693 ** hash table.
694 */
695 struct Module {
696   const sqlite3_module *pModule;       /* Callback pointers */
697   const char *zName;                   /* Name passed to create_module() */
698   void *pAux;                          /* pAux passed to create_module() */
699   void (*xDestroy)(void *);            /* Module destructor function */
700 };
701 
702 /*
703 ** Possible values for FuncDef.flags
704 */
705 #define SQLITE_FUNC_LIKE   0x01  /* Candidate for the LIKE optimization */
706 #define SQLITE_FUNC_CASE   0x02  /* Case-sensitive LIKE-type function */
707 #define SQLITE_FUNC_EPHEM  0x04  /* Ephermeral.  Delete with VDBE */
708 
709 /*
710 ** information about each column of an SQL table is held in an instance
711 ** of this structure.
712 */
713 struct Column {
714   char *zName;     /* Name of this column */
715   Expr *pDflt;     /* Default value of this column */
716   char *zType;     /* Data type for this column */
717   char *zColl;     /* Collating sequence.  If NULL, use the default */
718   u8 notNull;      /* True if there is a NOT NULL constraint */
719   u8 isPrimKey;    /* True if this column is part of the PRIMARY KEY */
720   char affinity;   /* One of the SQLITE_AFF_... values */
721 #ifndef SQLITE_OMIT_VIRTUALTABLE
722   u8 isHidden;     /* True if this column is 'hidden' */
723 #endif
724 };
725 
726 /*
727 ** A "Collating Sequence" is defined by an instance of the following
728 ** structure. Conceptually, a collating sequence consists of a name and
729 ** a comparison routine that defines the order of that sequence.
730 **
731 ** There may two seperate implementations of the collation function, one
732 ** that processes text in UTF-8 encoding (CollSeq.xCmp) and another that
733 ** processes text encoded in UTF-16 (CollSeq.xCmp16), using the machine
734 ** native byte order. When a collation sequence is invoked, SQLite selects
735 ** the version that will require the least expensive encoding
736 ** translations, if any.
737 **
738 ** The CollSeq.pUser member variable is an extra parameter that passed in
739 ** as the first argument to the UTF-8 comparison function, xCmp.
740 ** CollSeq.pUser16 is the equivalent for the UTF-16 comparison function,
741 ** xCmp16.
742 **
743 ** If both CollSeq.xCmp and CollSeq.xCmp16 are NULL, it means that the
744 ** collating sequence is undefined.  Indices built on an undefined
745 ** collating sequence may not be read or written.
746 */
747 struct CollSeq {
748   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
749   u8 enc;               /* Text encoding handled by xCmp() */
750   u8 type;              /* One of the SQLITE_COLL_... values below */
751   void *pUser;          /* First argument to xCmp() */
752   int (*xCmp)(void*,int, const void*, int, const void*);
753   void (*xDel)(void*);  /* Destructor for pUser */
754 };
755 
756 /*
757 ** Allowed values of CollSeq flags:
758 */
759 #define SQLITE_COLL_BINARY  1  /* The default memcmp() collating sequence */
760 #define SQLITE_COLL_NOCASE  2  /* The built-in NOCASE collating sequence */
761 #define SQLITE_COLL_REVERSE 3  /* The built-in REVERSE collating sequence */
762 #define SQLITE_COLL_USER    0  /* Any other user-defined collating sequence */
763 
764 /*
765 ** A sort order can be either ASC or DESC.
766 */
767 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
768 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
769 
770 /*
771 ** Column affinity types.
772 **
773 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
774 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
775 ** the speed a little by number the values consecutively.
776 **
777 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
778 ** when multiple affinity types are concatenated into a string and
779 ** used as the P4 operand, they will be more readable.
780 **
781 ** Note also that the numeric types are grouped together so that testing
782 ** for a numeric type is a single comparison.
783 */
784 #define SQLITE_AFF_TEXT     'a'
785 #define SQLITE_AFF_NONE     'b'
786 #define SQLITE_AFF_NUMERIC  'c'
787 #define SQLITE_AFF_INTEGER  'd'
788 #define SQLITE_AFF_REAL     'e'
789 
790 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
791 
792 /*
793 ** The SQLITE_AFF_MASK values masks off the significant bits of an
794 ** affinity value.
795 */
796 #define SQLITE_AFF_MASK     0x67
797 
798 /*
799 ** Additional bit values that can be ORed with an affinity without
800 ** changing the affinity.
801 */
802 #define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
803 #define SQLITE_NULLEQUAL    0x10  /* compare NULLs equal */
804 #define SQLITE_STOREP2      0x80  /* Store result in reg[P2] rather than jump */
805 
806 /*
807 ** Each SQL table is represented in memory by an instance of the
808 ** following structure.
809 **
810 ** Table.zName is the name of the table.  The case of the original
811 ** CREATE TABLE statement is stored, but case is not significant for
812 ** comparisons.
813 **
814 ** Table.nCol is the number of columns in this table.  Table.aCol is a
815 ** pointer to an array of Column structures, one for each column.
816 **
817 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
818 ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
819 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
820 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
821 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
822 ** is generated for each row of the table.  Table.hasPrimKey is true if
823 ** the table has any PRIMARY KEY, INTEGER or otherwise.
824 **
825 ** Table.tnum is the page number for the root BTree page of the table in the
826 ** database file.  If Table.iDb is the index of the database table backend
827 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
828 ** holds temporary tables and indices.  If Table.isEphem
829 ** is true, then the table is stored in a file that is automatically deleted
830 ** when the VDBE cursor to the table is closed.  In this case Table.tnum
831 ** refers VDBE cursor number that holds the table open, not to the root
832 ** page number.  Transient tables are used to hold the results of a
833 ** sub-query that appears instead of a real table name in the FROM clause
834 ** of a SELECT statement.
835 */
836 struct Table {
837   char *zName;     /* Name of the table */
838   int nCol;        /* Number of columns in this table */
839   Column *aCol;    /* Information about each column */
840   int iPKey;       /* If not less then 0, use aCol[iPKey] as the primary key */
841   Index *pIndex;   /* List of SQL indexes on this table. */
842   int tnum;        /* Root BTree node for this table (see note above) */
843   Select *pSelect; /* NULL for tables.  Points to definition if a view. */
844   int nRef;          /* Number of pointers to this Table */
845   Trigger *pTrigger; /* List of SQL triggers on this table */
846   FKey *pFKey;       /* Linked list of all foreign keys in this table */
847   char *zColAff;     /* String defining the affinity of each column */
848 #ifndef SQLITE_OMIT_CHECK
849   Expr *pCheck;      /* The AND of all CHECK constraints */
850 #endif
851 #ifndef SQLITE_OMIT_ALTERTABLE
852   int addColOffset;  /* Offset in CREATE TABLE statement to add a new column */
853 #endif
854   u8 readOnly;     /* True if this table should not be written by the user */
855   u8 isEphem;      /* True if created using OP_OpenEphermeral */
856   u8 hasPrimKey;   /* True if there exists a primary key */
857   u8 keyConf;      /* What to do in case of uniqueness conflict on iPKey */
858   u8 autoInc;      /* True if the integer primary key is autoincrement */
859 #ifndef SQLITE_OMIT_VIRTUALTABLE
860   u8 isVirtual;             /* True if this is a virtual table */
861   u8 isCommit;              /* True once the CREATE TABLE has been committed */
862   Module *pMod;             /* Pointer to the implementation of the module */
863   sqlite3_vtab *pVtab;      /* Pointer to the module instance */
864   int nModuleArg;           /* Number of arguments to the module */
865   char **azModuleArg;       /* Text of all module args. [0] is module name */
866 #endif
867   Schema *pSchema;          /* Schema that contains this table */
868 };
869 
870 /*
871 ** Test to see whether or not a table is a virtual table.  This is
872 ** done as a macro so that it will be optimized out when virtual
873 ** table support is omitted from the build.
874 */
875 #ifndef SQLITE_OMIT_VIRTUALTABLE
876 #  define IsVirtual(X)      ((X)->isVirtual)
877 #  define IsHiddenColumn(X) ((X)->isHidden)
878 #else
879 #  define IsVirtual(X)      0
880 #  define IsHiddenColumn(X) 0
881 #endif
882 
883 /*
884 ** Each foreign key constraint is an instance of the following structure.
885 **
886 ** A foreign key is associated with two tables.  The "from" table is
887 ** the table that contains the REFERENCES clause that creates the foreign
888 ** key.  The "to" table is the table that is named in the REFERENCES clause.
889 ** Consider this example:
890 **
891 **     CREATE TABLE ex1(
892 **       a INTEGER PRIMARY KEY,
893 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
894 **     );
895 **
896 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
897 **
898 ** Each REFERENCES clause generates an instance of the following structure
899 ** which is attached to the from-table.  The to-table need not exist when
900 ** the from-table is created.  The existance of the to-table is not checked
901 ** until an attempt is made to insert data into the from-table.
902 **
903 ** The sqlite.aFKey hash table stores pointers to this structure
904 ** given the name of a to-table.  For each to-table, all foreign keys
905 ** associated with that table are on a linked list using the FKey.pNextTo
906 ** field.
907 */
908 struct FKey {
909   Table *pFrom;     /* The table that constains the REFERENCES clause */
910   FKey *pNextFrom;  /* Next foreign key in pFrom */
911   char *zTo;        /* Name of table that the key points to */
912   FKey *pNextTo;    /* Next foreign key that points to zTo */
913   int nCol;         /* Number of columns in this key */
914   struct sColMap {  /* Mapping of columns in pFrom to columns in zTo */
915     int iFrom;         /* Index of column in pFrom */
916     char *zCol;        /* Name of column in zTo.  If 0 use PRIMARY KEY */
917   } *aCol;          /* One entry for each of nCol column s */
918   u8 isDeferred;    /* True if constraint checking is deferred till COMMIT */
919   u8 updateConf;    /* How to resolve conflicts that occur on UPDATE */
920   u8 deleteConf;    /* How to resolve conflicts that occur on DELETE */
921   u8 insertConf;    /* How to resolve conflicts that occur on INSERT */
922 };
923 
924 /*
925 ** SQLite supports many different ways to resolve a constraint
926 ** error.  ROLLBACK processing means that a constraint violation
927 ** causes the operation in process to fail and for the current transaction
928 ** to be rolled back.  ABORT processing means the operation in process
929 ** fails and any prior changes from that one operation are backed out,
930 ** but the transaction is not rolled back.  FAIL processing means that
931 ** the operation in progress stops and returns an error code.  But prior
932 ** changes due to the same operation are not backed out and no rollback
933 ** occurs.  IGNORE means that the particular row that caused the constraint
934 ** error is not inserted or updated.  Processing continues and no error
935 ** is returned.  REPLACE means that preexisting database rows that caused
936 ** a UNIQUE constraint violation are removed so that the new insert or
937 ** update can proceed.  Processing continues and no error is reported.
938 **
939 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
940 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
941 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
942 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
943 ** referenced table row is propagated into the row that holds the
944 ** foreign key.
945 **
946 ** The following symbolic values are used to record which type
947 ** of action to take.
948 */
949 #define OE_None     0   /* There is no constraint to check */
950 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
951 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
952 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
953 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
954 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
955 
956 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
957 #define OE_SetNull  7   /* Set the foreign key value to NULL */
958 #define OE_SetDflt  8   /* Set the foreign key value to its default */
959 #define OE_Cascade  9   /* Cascade the changes */
960 
961 #define OE_Default  99  /* Do whatever the default action is */
962 
963 
964 /*
965 ** An instance of the following structure is passed as the first
966 ** argument to sqlite3VdbeKeyCompare and is used to control the
967 ** comparison of the two index keys.
968 **
969 ** If the KeyInfo.incrKey value is true and the comparison would
970 ** otherwise be equal, then return a result as if the second key
971 ** were larger.
972 */
973 struct KeyInfo {
974   sqlite3 *db;        /* The database connection */
975   u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
976   u8 incrKey;         /* Increase 2nd key by epsilon before comparison */
977   u8 prefixIsEqual;   /* Treat a prefix as equal */
978   int nField;         /* Number of entries in aColl[] */
979   u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
980   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
981 };
982 
983 /*
984 ** Each SQL index is represented in memory by an
985 ** instance of the following structure.
986 **
987 ** The columns of the table that are to be indexed are described
988 ** by the aiColumn[] field of this structure.  For example, suppose
989 ** we have the following table and index:
990 **
991 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
992 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
993 **
994 ** In the Table structure describing Ex1, nCol==3 because there are
995 ** three columns in the table.  In the Index structure describing
996 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
997 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
998 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
999 ** The second column to be indexed (c1) has an index of 0 in
1000 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
1001 **
1002 ** The Index.onError field determines whether or not the indexed columns
1003 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
1004 ** it means this is not a unique index.  Otherwise it is a unique index
1005 ** and the value of Index.onError indicate the which conflict resolution
1006 ** algorithm to employ whenever an attempt is made to insert a non-unique
1007 ** element.
1008 */
1009 struct Index {
1010   char *zName;     /* Name of this index */
1011   int nColumn;     /* Number of columns in the table used by this index */
1012   int *aiColumn;   /* Which columns are used by this index.  1st is 0 */
1013   unsigned *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
1014   Table *pTable;   /* The SQL table being indexed */
1015   int tnum;        /* Page containing root of this index in database file */
1016   u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
1017   u8 autoIndex;    /* True if is automatically created (ex: by UNIQUE) */
1018   char *zColAff;   /* String defining the affinity of each column */
1019   Index *pNext;    /* The next index associated with the same table */
1020   Schema *pSchema; /* Schema containing this index */
1021   u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
1022   char **azColl;   /* Array of collation sequence names for index */
1023 };
1024 
1025 /*
1026 ** Each token coming out of the lexer is an instance of
1027 ** this structure.  Tokens are also used as part of an expression.
1028 **
1029 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
1030 ** may contain random values.  Do not make any assuptions about Token.dyn
1031 ** and Token.n when Token.z==0.
1032 */
1033 struct Token {
1034   const unsigned char *z; /* Text of the token.  Not NULL-terminated! */
1035   unsigned dyn  : 1;      /* True for malloced memory, false for static */
1036   unsigned n    : 31;     /* Number of characters in this token */
1037 };
1038 
1039 /*
1040 ** An instance of this structure contains information needed to generate
1041 ** code for a SELECT that contains aggregate functions.
1042 **
1043 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
1044 ** pointer to this structure.  The Expr.iColumn field is the index in
1045 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
1046 ** code for that node.
1047 **
1048 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
1049 ** original Select structure that describes the SELECT statement.  These
1050 ** fields do not need to be freed when deallocating the AggInfo structure.
1051 */
1052 struct AggInfo {
1053   u8 directMode;          /* Direct rendering mode means take data directly
1054                           ** from source tables rather than from accumulators */
1055   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
1056                           ** than the source table */
1057   int sortingIdx;         /* Cursor number of the sorting index */
1058   ExprList *pGroupBy;     /* The group by clause */
1059   int nSortingColumn;     /* Number of columns in the sorting index */
1060   struct AggInfo_col {    /* For each column used in source tables */
1061     Table *pTab;             /* Source table */
1062     int iTable;              /* Cursor number of the source table */
1063     int iColumn;             /* Column number within the source table */
1064     int iSorterColumn;       /* Column number in the sorting index */
1065     int iMem;                /* Memory location that acts as accumulator */
1066     Expr *pExpr;             /* The original expression */
1067   } *aCol;
1068   int nColumn;            /* Number of used entries in aCol[] */
1069   int nColumnAlloc;       /* Number of slots allocated for aCol[] */
1070   int nAccumulator;       /* Number of columns that show through to the output.
1071                           ** Additional columns are used only as parameters to
1072                           ** aggregate functions */
1073   struct AggInfo_func {   /* For each aggregate function */
1074     Expr *pExpr;             /* Expression encoding the function */
1075     FuncDef *pFunc;          /* The aggregate function implementation */
1076     int iMem;                /* Memory location that acts as accumulator */
1077     int iDistinct;           /* Ephermeral table used to enforce DISTINCT */
1078   } *aFunc;
1079   int nFunc;              /* Number of entries in aFunc[] */
1080   int nFuncAlloc;         /* Number of slots allocated for aFunc[] */
1081 };
1082 
1083 /*
1084 ** Each node of an expression in the parse tree is an instance
1085 ** of this structure.
1086 **
1087 ** Expr.op is the opcode.  The integer parser token codes are reused
1088 ** as opcodes here.  For example, the parser defines TK_GE to be an integer
1089 ** code representing the ">=" operator.  This same integer code is reused
1090 ** to represent the greater-than-or-equal-to operator in the expression
1091 ** tree.
1092 **
1093 ** Expr.pRight and Expr.pLeft are subexpressions.  Expr.pList is a list
1094 ** of argument if the expression is a function.
1095 **
1096 ** Expr.token is the operator token for this node.  For some expressions
1097 ** that have subexpressions, Expr.token can be the complete text that gave
1098 ** rise to the Expr.  In the latter case, the token is marked as being
1099 ** a compound token.
1100 **
1101 ** An expression of the form ID or ID.ID refers to a column in a table.
1102 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
1103 ** the integer cursor number of a VDBE cursor pointing to that table and
1104 ** Expr.iColumn is the column number for the specific column.  If the
1105 ** expression is used as a result in an aggregate SELECT, then the
1106 ** value is also stored in the Expr.iAgg column in the aggregate so that
1107 ** it can be accessed after all aggregates are computed.
1108 **
1109 ** If the expression is a function, the Expr.iTable is an integer code
1110 ** representing which function.  If the expression is an unbound variable
1111 ** marker (a question mark character '?' in the original SQL) then the
1112 ** Expr.iTable holds the index number for that variable.
1113 **
1114 ** If the expression is a subquery then Expr.iColumn holds an integer
1115 ** register number containing the result of the subquery.  If the
1116 ** subquery gives a constant result, then iTable is -1.  If the subquery
1117 ** gives a different answer at different times during statement processing
1118 ** then iTable is the address of a subroutine that computes the subquery.
1119 **
1120 ** The Expr.pSelect field points to a SELECT statement.  The SELECT might
1121 ** be the right operand of an IN operator.  Or, if a scalar SELECT appears
1122 ** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
1123 ** operand.
1124 **
1125 ** If the Expr is of type OP_Column, and the table it is selecting from
1126 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
1127 ** corresponding table definition.
1128 */
1129 struct Expr {
1130   u8 op;                 /* Operation performed by this node */
1131   char affinity;         /* The affinity of the column or 0 if not a column */
1132   u16 flags;             /* Various flags.  See below */
1133   CollSeq *pColl;        /* The collation type of the column or 0 */
1134   Expr *pLeft, *pRight;  /* Left and right subnodes */
1135   ExprList *pList;       /* A list of expressions used as function arguments
1136                          ** or in "<expr> IN (<expr-list)" */
1137   Token token;           /* An operand token */
1138   Token span;            /* Complete text of the expression */
1139   int iTable, iColumn;   /* When op==TK_COLUMN, then this expr node means the
1140                          ** iColumn-th field of the iTable-th table. */
1141   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
1142   int iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
1143   int iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
1144   Select *pSelect;       /* When the expression is a sub-select.  Also the
1145                          ** right side of "<expr> IN (<select>)" */
1146   Table *pTab;           /* Table for OP_Column expressions. */
1147 /*  Schema *pSchema; */
1148 #if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
1149   int nHeight;           /* Height of the tree headed by this node */
1150 #endif
1151 };
1152 
1153 /*
1154 ** The following are the meanings of bits in the Expr.flags field.
1155 */
1156 #define EP_FromJoin   0x0001  /* Originated in ON or USING clause of a join */
1157 #define EP_Agg        0x0002  /* Contains one or more aggregate functions */
1158 #define EP_Resolved   0x0004  /* IDs have been resolved to COLUMNs */
1159 #define EP_Error      0x0008  /* Expression contains one or more errors */
1160 #define EP_Distinct   0x0010  /* Aggregate function with DISTINCT keyword */
1161 #define EP_VarSelect  0x0020  /* pSelect is correlated, not constant */
1162 #define EP_Dequoted   0x0040  /* True if the string has been dequoted */
1163 #define EP_InfixFunc  0x0080  /* True for an infix function: LIKE, GLOB, etc */
1164 #define EP_ExpCollate 0x0100  /* Collating sequence specified explicitly */
1165 #define EP_AnyAff     0x0200  /* Can take a cached column of any affinity */
1166 #define EP_FixedDest  0x0400  /* Result needed in a specific register */
1167 
1168 /*
1169 ** These macros can be used to test, set, or clear bits in the
1170 ** Expr.flags field.
1171 */
1172 #define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
1173 #define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
1174 #define ExprSetProperty(E,P)     (E)->flags|=(P)
1175 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
1176 
1177 /*
1178 ** A list of expressions.  Each expression may optionally have a
1179 ** name.  An expr/name combination can be used in several ways, such
1180 ** as the list of "expr AS ID" fields following a "SELECT" or in the
1181 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
1182 ** also be used as the argument to a function, in which case the a.zName
1183 ** field is not used.
1184 */
1185 struct ExprList {
1186   int nExpr;             /* Number of expressions on the list */
1187   int nAlloc;            /* Number of entries allocated below */
1188   int iECursor;          /* VDBE Cursor associated with this ExprList */
1189   struct ExprList_item {
1190     Expr *pExpr;           /* The list of expressions */
1191     char *zName;           /* Token associated with this expression */
1192     u8 sortOrder;          /* 1 for DESC or 0 for ASC */
1193     u8 isAgg;              /* True if this is an aggregate like count(*) */
1194     u8 done;               /* A flag to indicate when processing is finished */
1195   } *a;                  /* One entry for each expression */
1196 };
1197 
1198 /*
1199 ** An instance of this structure can hold a simple list of identifiers,
1200 ** such as the list "a,b,c" in the following statements:
1201 **
1202 **      INSERT INTO t(a,b,c) VALUES ...;
1203 **      CREATE INDEX idx ON t(a,b,c);
1204 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
1205 **
1206 ** The IdList.a.idx field is used when the IdList represents the list of
1207 ** column names after a table name in an INSERT statement.  In the statement
1208 **
1209 **     INSERT INTO t(a,b,c) ...
1210 **
1211 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
1212 */
1213 struct IdList {
1214   struct IdList_item {
1215     char *zName;      /* Name of the identifier */
1216     int idx;          /* Index in some Table.aCol[] of a column named zName */
1217   } *a;
1218   int nId;         /* Number of identifiers on the list */
1219   int nAlloc;      /* Number of entries allocated for a[] below */
1220 };
1221 
1222 /*
1223 ** The bitmask datatype defined below is used for various optimizations.
1224 **
1225 ** Changing this from a 64-bit to a 32-bit type limits the number of
1226 ** tables in a join to 32 instead of 64.  But it also reduces the size
1227 ** of the library by 738 bytes on ix86.
1228 */
1229 typedef u64 Bitmask;
1230 
1231 /*
1232 ** The following structure describes the FROM clause of a SELECT statement.
1233 ** Each table or subquery in the FROM clause is a separate element of
1234 ** the SrcList.a[] array.
1235 **
1236 ** With the addition of multiple database support, the following structure
1237 ** can also be used to describe a particular table such as the table that
1238 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
1239 ** such a table must be a simple name: ID.  But in SQLite, the table can
1240 ** now be identified by a database name, a dot, then the table name: ID.ID.
1241 **
1242 ** The jointype starts out showing the join type between the current table
1243 ** and the next table on the list.  The parser builds the list this way.
1244 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
1245 ** jointype expresses the join between the table and the previous table.
1246 */
1247 struct SrcList {
1248   i16 nSrc;        /* Number of tables or subqueries in the FROM clause */
1249   i16 nAlloc;      /* Number of entries allocated in a[] below */
1250   struct SrcList_item {
1251     char *zDatabase;  /* Name of database holding this table */
1252     char *zName;      /* Name of the table */
1253     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
1254     Table *pTab;      /* An SQL table corresponding to zName */
1255     Select *pSelect;  /* A SELECT statement used in place of a table name */
1256     u8 isPopulated;   /* Temporary table associated with SELECT is populated */
1257     u8 jointype;      /* Type of join between this able and the previous */
1258     int iCursor;      /* The VDBE cursor number used to access this table */
1259     Expr *pOn;        /* The ON clause of a join */
1260     IdList *pUsing;   /* The USING clause of a join */
1261     Bitmask colUsed;  /* Bit N (1<<N) set if column N or pTab is used */
1262   } a[1];             /* One entry for each identifier on the list */
1263 };
1264 
1265 /*
1266 ** Permitted values of the SrcList.a.jointype field
1267 */
1268 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
1269 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
1270 #define JT_NATURAL   0x0004    /* True for a "natural" join */
1271 #define JT_LEFT      0x0008    /* Left outer join */
1272 #define JT_RIGHT     0x0010    /* Right outer join */
1273 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
1274 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
1275 
1276 /*
1277 ** For each nested loop in a WHERE clause implementation, the WhereInfo
1278 ** structure contains a single instance of this structure.  This structure
1279 ** is intended to be private the the where.c module and should not be
1280 ** access or modified by other modules.
1281 **
1282 ** The pIdxInfo and pBestIdx fields are used to help pick the best
1283 ** index on a virtual table.  The pIdxInfo pointer contains indexing
1284 ** information for the i-th table in the FROM clause before reordering.
1285 ** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
1286 ** The pBestIdx pointer is a copy of pIdxInfo for the i-th table after
1287 ** FROM clause ordering.  This is a little confusing so I will repeat
1288 ** it in different words.  WhereInfo.a[i].pIdxInfo is index information
1289 ** for WhereInfo.pTabList.a[i].  WhereInfo.a[i].pBestInfo is the
1290 ** index information for the i-th loop of the join.  pBestInfo is always
1291 ** either NULL or a copy of some pIdxInfo.  So for cleanup it is
1292 ** sufficient to free all of the pIdxInfo pointers.
1293 **
1294 */
1295 struct WhereLevel {
1296   int iFrom;            /* Which entry in the FROM clause */
1297   int flags;            /* Flags associated with this level */
1298   int iMem;             /* First memory cell used by this level */
1299   int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
1300   Index *pIdx;          /* Index used.  NULL if no index */
1301   int iTabCur;          /* The VDBE cursor used to access the table */
1302   int iIdxCur;          /* The VDBE cursor used to acesss pIdx */
1303   int brk;              /* Jump here to break out of the loop */
1304   int nxt;              /* Jump here to start the next IN combination */
1305   int cont;             /* Jump here to continue with the next loop cycle */
1306   int top;              /* First instruction of interior of the loop */
1307   int op, p1, p2;       /* Opcode used to terminate the loop */
1308   int nEq;              /* Number of == or IN constraints on this loop */
1309   int nIn;              /* Number of IN operators constraining this loop */
1310   struct InLoop {
1311     int iCur;              /* The VDBE cursor used by this IN operator */
1312     int topAddr;           /* Top of the IN loop */
1313   } *aInLoop;           /* Information about each nested IN operator */
1314   sqlite3_index_info *pBestIdx;  /* Index information for this level */
1315 
1316   /* The following field is really not part of the current level.  But
1317   ** we need a place to cache index information for each table in the
1318   ** FROM clause and the WhereLevel structure is a convenient place.
1319   */
1320   sqlite3_index_info *pIdxInfo;  /* Index info for n-th source table */
1321 };
1322 
1323 /*
1324 ** Flags appropriate for the wflags parameter of sqlite3WhereBegin().
1325 */
1326 #define WHERE_ORDERBY_NORMAL     0   /* No-op */
1327 #define WHERE_ORDERBY_MIN        1   /* ORDER BY processing for min() func */
1328 #define WHERE_ORDERBY_MAX        2   /* ORDER BY processing for max() func */
1329 #define WHERE_ONEPASS_DESIRED    4   /* Want to do one-pass UPDATE/DELETE */
1330 
1331 /*
1332 ** The WHERE clause processing routine has two halves.  The
1333 ** first part does the start of the WHERE loop and the second
1334 ** half does the tail of the WHERE loop.  An instance of
1335 ** this structure is returned by the first half and passed
1336 ** into the second half to give some continuity.
1337 */
1338 struct WhereInfo {
1339   Parse *pParse;       /* Parsing and code generating context */
1340   u8 okOnePass;        /* Ok to use one-pass algorithm for UPDATE or DELETE */
1341   SrcList *pTabList;   /* List of tables in the join */
1342   int iTop;            /* The very beginning of the WHERE loop */
1343   int iContinue;       /* Jump here to continue with next record */
1344   int iBreak;          /* Jump here to break out of the loop */
1345   int nLevel;          /* Number of nested loop */
1346   sqlite3_index_info **apInfo;  /* Array of pointers to index info structures */
1347   WhereLevel a[1];     /* Information about each nest loop in the WHERE */
1348 };
1349 
1350 /*
1351 ** A NameContext defines a context in which to resolve table and column
1352 ** names.  The context consists of a list of tables (the pSrcList) field and
1353 ** a list of named expression (pEList).  The named expression list may
1354 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
1355 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
1356 ** pEList corresponds to the result set of a SELECT and is NULL for
1357 ** other statements.
1358 **
1359 ** NameContexts can be nested.  When resolving names, the inner-most
1360 ** context is searched first.  If no match is found, the next outer
1361 ** context is checked.  If there is still no match, the next context
1362 ** is checked.  This process continues until either a match is found
1363 ** or all contexts are check.  When a match is found, the nRef member of
1364 ** the context containing the match is incremented.
1365 **
1366 ** Each subquery gets a new NameContext.  The pNext field points to the
1367 ** NameContext in the parent query.  Thus the process of scanning the
1368 ** NameContext list corresponds to searching through successively outer
1369 ** subqueries looking for a match.
1370 */
1371 struct NameContext {
1372   Parse *pParse;       /* The parser */
1373   SrcList *pSrcList;   /* One or more tables used to resolve names */
1374   ExprList *pEList;    /* Optional list of named expressions */
1375   int nRef;            /* Number of names resolved by this context */
1376   int nErr;            /* Number of errors encountered while resolving names */
1377   u8 allowAgg;         /* Aggregate functions allowed here */
1378   u8 hasAgg;           /* True if aggregates are seen */
1379   u8 isCheck;          /* True if resolving names in a CHECK constraint */
1380   int nDepth;          /* Depth of subquery recursion. 1 for no recursion */
1381   AggInfo *pAggInfo;   /* Information about aggregates at this level */
1382   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
1383 };
1384 
1385 /*
1386 ** An instance of the following structure contains all information
1387 ** needed to generate code for a single SELECT statement.
1388 **
1389 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
1390 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
1391 ** limit and nOffset to the value of the offset (or 0 if there is not
1392 ** offset).  But later on, nLimit and nOffset become the memory locations
1393 ** in the VDBE that record the limit and offset counters.
1394 **
1395 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
1396 ** These addresses must be stored so that we can go back and fill in
1397 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
1398 ** the number of columns in P2 can be computed at the same time
1399 ** as the OP_OpenEphm instruction is coded because not
1400 ** enough information about the compound query is known at that point.
1401 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
1402 ** for the result set.  The KeyInfo for addrOpenTran[2] contains collating
1403 ** sequences for the ORDER BY clause.
1404 */
1405 struct Select {
1406   ExprList *pEList;      /* The fields of the result */
1407   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
1408   u8 isDistinct;         /* True if the DISTINCT keyword is present */
1409   u8 isResolved;         /* True once sqlite3SelectResolve() has run. */
1410   u8 isAgg;              /* True if this is an aggregate query */
1411   u8 usesEphm;           /* True if uses an OpenEphemeral opcode */
1412   u8 disallowOrderBy;    /* Do not allow an ORDER BY to be attached if TRUE */
1413   char affinity;         /* MakeRecord with this affinity for SRT_Set */
1414   SrcList *pSrc;         /* The FROM clause */
1415   Expr *pWhere;          /* The WHERE clause */
1416   ExprList *pGroupBy;    /* The GROUP BY clause */
1417   Expr *pHaving;         /* The HAVING clause */
1418   ExprList *pOrderBy;    /* The ORDER BY clause */
1419   Select *pPrior;        /* Prior select in a compound select statement */
1420   Select *pNext;         /* Next select to the left in a compound */
1421   Select *pRightmost;    /* Right-most select in a compound select statement */
1422   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
1423   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
1424   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
1425   int addrOpenEphm[3];   /* OP_OpenEphem opcodes related to this select */
1426 };
1427 
1428 /*
1429 ** The results of a select can be distributed in several ways.
1430 */
1431 #define SRT_Union        1  /* Store result as keys in an index */
1432 #define SRT_Except       2  /* Remove result from a UNION index */
1433 #define SRT_Exists       3  /* Store 1 if the result is not empty */
1434 #define SRT_Discard      4  /* Do not save the results anywhere */
1435 
1436 /* The ORDER BY clause is ignored for all of the above */
1437 #define IgnorableOrderby(X) ((X->eDest)<=SRT_Discard)
1438 
1439 #define SRT_Callback     5  /* Invoke a callback with each row of result */
1440 #define SRT_Mem          6  /* Store result in a memory cell */
1441 #define SRT_Set          7  /* Store non-null results as keys in an index */
1442 #define SRT_Table        8  /* Store result as data with an automatic rowid */
1443 #define SRT_EphemTab     9  /* Create transient tab and store like SRT_Table */
1444 #define SRT_Subroutine  10  /* Call a subroutine to handle results */
1445 
1446 /*
1447 ** A structure used to customize the behaviour of sqlite3Select(). See
1448 ** comments above sqlite3Select() for details.
1449 */
1450 typedef struct SelectDest SelectDest;
1451 struct SelectDest {
1452   u8 eDest;         /* How to dispose of the results */
1453   u8 affinity;      /* Affinity used when eDest==SRT_Set */
1454   int iParm;        /* A parameter used by the eDest disposal method */
1455   int iMem;         /* Base register where results are written */
1456   int nMem;         /* Number of registers allocated */
1457 };
1458 
1459 /*
1460 ** An SQL parser context.  A copy of this structure is passed through
1461 ** the parser and down into all the parser action routine in order to
1462 ** carry around information that is global to the entire parse.
1463 **
1464 ** The structure is divided into two parts.  When the parser and code
1465 ** generate call themselves recursively, the first part of the structure
1466 ** is constant but the second part is reset at the beginning and end of
1467 ** each recursion.
1468 **
1469 ** The nTableLock and aTableLock variables are only used if the shared-cache
1470 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
1471 ** used to store the set of table-locks required by the statement being
1472 ** compiled. Function sqlite3TableLock() is used to add entries to the
1473 ** list.
1474 */
1475 struct Parse {
1476   sqlite3 *db;         /* The main database structure */
1477   int rc;              /* Return code from execution */
1478   char *zErrMsg;       /* An error message */
1479   Vdbe *pVdbe;         /* An engine for executing database bytecode */
1480   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
1481   u8 nameClash;        /* A permanent table name clashes with temp table name */
1482   u8 checkSchema;      /* Causes schema cookie check after an error */
1483   u8 nested;           /* Number of nested calls to the parser/code generator */
1484   u8 parseError;       /* True after a parsing error.  Ticket #1794 */
1485   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
1486   u8 nTempInUse;       /* Number of aTempReg[] currently checked out */
1487   int aTempReg[8];     /* Holding area for temporary registers */
1488   int nRangeReg;       /* Size of the temporary register block */
1489   int iRangeReg;       /* First register in temporary register block */
1490   int nErr;            /* Number of errors seen */
1491   int nTab;            /* Number of previously allocated VDBE cursors */
1492   int nMem;            /* Number of memory cells used so far */
1493   int nSet;            /* Number of sets used so far */
1494   int ckBase;          /* Base register of data during check constraints */
1495   int disableColCache; /* True to disable adding to column cache */
1496   int nColCache;       /* Number of entries in the column cache */
1497   int iColCache;       /* Next entry of the cache to replace */
1498   struct yColCache {
1499     int iTable;           /* Table cursor number */
1500     int iColumn;          /* Table column number */
1501     char affChange;       /* True if this register has had an affinity change */
1502     int iReg;             /* Register holding value of this column */
1503   } aColCache[10];     /* One for each valid column cache entry */
1504   u32 writeMask;       /* Start a write transaction on these databases */
1505   u32 cookieMask;      /* Bitmask of schema verified databases */
1506   int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
1507   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
1508 #ifndef SQLITE_OMIT_SHARED_CACHE
1509   int nTableLock;        /* Number of locks in aTableLock */
1510   TableLock *aTableLock; /* Required table locks for shared-cache mode */
1511 #endif
1512   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
1513   int regRoot;         /* Register holding root page number for new objects */
1514 
1515   /* Above is constant between recursions.  Below is reset before and after
1516   ** each recursion */
1517 
1518   int nVar;            /* Number of '?' variables seen in the SQL so far */
1519   int nVarExpr;        /* Number of used slots in apVarExpr[] */
1520   int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
1521   Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
1522   u8 explain;          /* True if the EXPLAIN flag is found on the query */
1523   Token sErrToken;     /* The token at which the error occurred */
1524   Token sNameToken;    /* Token with unqualified schema object name */
1525   Token sLastToken;    /* The last token parsed */
1526   const char *zSql;    /* All SQL text */
1527   const char *zTail;   /* All SQL text past the last semicolon parsed */
1528   Table *pNewTable;    /* A table being constructed by CREATE TABLE */
1529   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
1530   TriggerStack *trigStack;  /* Trigger actions being coded */
1531   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
1532 #ifndef SQLITE_OMIT_VIRTUALTABLE
1533   Token sArg;                /* Complete text of a module argument */
1534   u8 declareVtab;            /* True if inside sqlite3_declare_vtab() */
1535   Table *pVirtualLock;       /* Require virtual table lock on this table */
1536 #endif
1537 #if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
1538   int nHeight;            /* Expression tree height of current sub-select */
1539 #endif
1540 };
1541 
1542 #ifdef SQLITE_OMIT_VIRTUALTABLE
1543   #define IN_DECLARE_VTAB 0
1544 #else
1545   #define IN_DECLARE_VTAB (pParse->declareVtab)
1546 #endif
1547 
1548 /*
1549 ** An instance of the following structure can be declared on a stack and used
1550 ** to save the Parse.zAuthContext value so that it can be restored later.
1551 */
1552 struct AuthContext {
1553   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
1554   Parse *pParse;              /* The Parse structure */
1555 };
1556 
1557 /*
1558 ** Bitfield flags for P2 value in OP_Insert and OP_Delete
1559 */
1560 #define OPFLAG_NCHANGE   1    /* Set to update db->nChange */
1561 #define OPFLAG_LASTROWID 2    /* Set to update db->lastRowid */
1562 #define OPFLAG_ISUPDATE  4    /* This OP_Insert is an sql UPDATE */
1563 #define OPFLAG_APPEND    8    /* This is likely to be an append */
1564 
1565 /*
1566  * Each trigger present in the database schema is stored as an instance of
1567  * struct Trigger.
1568  *
1569  * Pointers to instances of struct Trigger are stored in two ways.
1570  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
1571  *    database). This allows Trigger structures to be retrieved by name.
1572  * 2. All triggers associated with a single table form a linked list, using the
1573  *    pNext member of struct Trigger. A pointer to the first element of the
1574  *    linked list is stored as the "pTrigger" member of the associated
1575  *    struct Table.
1576  *
1577  * The "step_list" member points to the first element of a linked list
1578  * containing the SQL statements specified as the trigger program.
1579  */
1580 struct Trigger {
1581   char *name;             /* The name of the trigger                        */
1582   char *table;            /* The table or view to which the trigger applies */
1583   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
1584   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
1585   Expr *pWhen;            /* The WHEN clause of the expresion (may be NULL) */
1586   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
1587                              the <column-list> is stored here */
1588   Token nameToken;        /* Token containing zName. Use during parsing only */
1589   Schema *pSchema;        /* Schema containing the trigger */
1590   Schema *pTabSchema;     /* Schema containing the table */
1591   TriggerStep *step_list; /* Link list of trigger program steps             */
1592   Trigger *pNext;         /* Next trigger associated with the table */
1593 };
1594 
1595 /*
1596 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
1597 ** determine which.
1598 **
1599 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
1600 ** In that cases, the constants below can be ORed together.
1601 */
1602 #define TRIGGER_BEFORE  1
1603 #define TRIGGER_AFTER   2
1604 
1605 /*
1606  * An instance of struct TriggerStep is used to store a single SQL statement
1607  * that is a part of a trigger-program.
1608  *
1609  * Instances of struct TriggerStep are stored in a singly linked list (linked
1610  * using the "pNext" member) referenced by the "step_list" member of the
1611  * associated struct Trigger instance. The first element of the linked list is
1612  * the first step of the trigger-program.
1613  *
1614  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
1615  * "SELECT" statement. The meanings of the other members is determined by the
1616  * value of "op" as follows:
1617  *
1618  * (op == TK_INSERT)
1619  * orconf    -> stores the ON CONFLICT algorithm
1620  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
1621  *              this stores a pointer to the SELECT statement. Otherwise NULL.
1622  * target    -> A token holding the name of the table to insert into.
1623  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
1624  *              this stores values to be inserted. Otherwise NULL.
1625  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
1626  *              statement, then this stores the column-names to be
1627  *              inserted into.
1628  *
1629  * (op == TK_DELETE)
1630  * target    -> A token holding the name of the table to delete from.
1631  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
1632  *              Otherwise NULL.
1633  *
1634  * (op == TK_UPDATE)
1635  * target    -> A token holding the name of the table to update rows of.
1636  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
1637  *              Otherwise NULL.
1638  * pExprList -> A list of the columns to update and the expressions to update
1639  *              them to. See sqlite3Update() documentation of "pChanges"
1640  *              argument.
1641  *
1642  */
1643 struct TriggerStep {
1644   int op;              /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
1645   int orconf;          /* OE_Rollback etc. */
1646   Trigger *pTrig;      /* The trigger that this step is a part of */
1647 
1648   Select *pSelect;     /* Valid for SELECT and sometimes
1649                           INSERT steps (when pExprList == 0) */
1650   Token target;        /* Valid for DELETE, UPDATE, INSERT steps */
1651   Expr *pWhere;        /* Valid for DELETE, UPDATE steps */
1652   ExprList *pExprList; /* Valid for UPDATE statements and sometimes
1653                            INSERT steps (when pSelect == 0)         */
1654   IdList *pIdList;     /* Valid for INSERT statements only */
1655   TriggerStep *pNext;  /* Next in the link-list */
1656   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
1657 };
1658 
1659 /*
1660  * An instance of struct TriggerStack stores information required during code
1661  * generation of a single trigger program. While the trigger program is being
1662  * coded, its associated TriggerStack instance is pointed to by the
1663  * "pTriggerStack" member of the Parse structure.
1664  *
1665  * The pTab member points to the table that triggers are being coded on. The
1666  * newIdx member contains the index of the vdbe cursor that points at the temp
1667  * table that stores the new.* references. If new.* references are not valid
1668  * for the trigger being coded (for example an ON DELETE trigger), then newIdx
1669  * is set to -1. The oldIdx member is analogous to newIdx, for old.* references.
1670  *
1671  * The ON CONFLICT policy to be used for the trigger program steps is stored
1672  * as the orconf member. If this is OE_Default, then the ON CONFLICT clause
1673  * specified for individual triggers steps is used.
1674  *
1675  * struct TriggerStack has a "pNext" member, to allow linked lists to be
1676  * constructed. When coding nested triggers (triggers fired by other triggers)
1677  * each nested trigger stores its parent trigger's TriggerStack as the "pNext"
1678  * pointer. Once the nested trigger has been coded, the pNext value is restored
1679  * to the pTriggerStack member of the Parse stucture and coding of the parent
1680  * trigger continues.
1681  *
1682  * Before a nested trigger is coded, the linked list pointed to by the
1683  * pTriggerStack is scanned to ensure that the trigger is not about to be coded
1684  * recursively. If this condition is detected, the nested trigger is not coded.
1685  */
1686 struct TriggerStack {
1687   Table *pTab;         /* Table that triggers are currently being coded on */
1688   int newIdx;          /* Index of vdbe cursor to "new" temp table */
1689   int oldIdx;          /* Index of vdbe cursor to "old" temp table */
1690   u32 newColMask;
1691   u32 oldColMask;
1692   int orconf;          /* Current orconf policy */
1693   int ignoreJump;      /* where to jump to for a RAISE(IGNORE) */
1694   Trigger *pTrigger;   /* The trigger currently being coded */
1695   TriggerStack *pNext; /* Next trigger down on the trigger stack */
1696 };
1697 
1698 /*
1699 ** The following structure contains information used by the sqliteFix...
1700 ** routines as they walk the parse tree to make database references
1701 ** explicit.
1702 */
1703 typedef struct DbFixer DbFixer;
1704 struct DbFixer {
1705   Parse *pParse;      /* The parsing context.  Error messages written here */
1706   const char *zDb;    /* Make sure all objects are contained in this database */
1707   const char *zType;  /* Type of the container - used for error messages */
1708   const Token *pName; /* Name of the container - used for error messages */
1709 };
1710 
1711 /*
1712 ** An objected used to accumulate the text of a string where we
1713 ** do not necessarily know how big the string will be in the end.
1714 */
1715 struct StrAccum {
1716   char *zBase;     /* A base allocation.  Not from malloc. */
1717   char *zText;     /* The string collected so far */
1718   int  nChar;      /* Length of the string so far */
1719   int  nAlloc;     /* Amount of space allocated in zText */
1720   int  mxAlloc;        /* Maximum allowed string length */
1721   u8   mallocFailed;   /* Becomes true if any memory allocation fails */
1722   u8   useMalloc;      /* True if zText is enlargable using realloc */
1723   u8   tooBig;         /* Becomes true if string size exceeds limits */
1724 };
1725 
1726 /*
1727 ** A pointer to this structure is used to communicate information
1728 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
1729 */
1730 typedef struct {
1731   sqlite3 *db;        /* The database being initialized */
1732   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
1733   char **pzErrMsg;    /* Error message stored here */
1734   int rc;             /* Result code stored here */
1735 } InitData;
1736 
1737 /*
1738 ** Assuming zIn points to the first byte of a UTF-8 character,
1739 ** advance zIn to point to the first byte of the next UTF-8 character.
1740 */
1741 #define SQLITE_SKIP_UTF8(zIn) {                        \
1742   if( (*(zIn++))>=0xc0 ){                              \
1743     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
1744   }                                                    \
1745 }
1746 
1747 /*
1748 ** The SQLITE_CORRUPT_BKPT macro can be either a constant (for production
1749 ** builds) or a function call (for debugging).  If it is a function call,
1750 ** it allows the operator to set a breakpoint at the spot where database
1751 ** corruption is first detected.
1752 */
1753 #ifdef SQLITE_DEBUG
1754   int sqlite3Corrupt(void);
1755 # define SQLITE_CORRUPT_BKPT sqlite3Corrupt()
1756 # define DEBUGONLY(X)        X
1757 #else
1758 # define SQLITE_CORRUPT_BKPT SQLITE_CORRUPT
1759 # define DEBUGONLY(X)
1760 #endif
1761 
1762 /*
1763 ** Internal function prototypes
1764 */
1765 int sqlite3StrICmp(const char *, const char *);
1766 int sqlite3StrNICmp(const char *, const char *, int);
1767 int sqlite3IsNumber(const char*, int*, u8);
1768 
1769 void *sqlite3MallocZero(unsigned);
1770 void *sqlite3DbMallocZero(sqlite3*, unsigned);
1771 void *sqlite3DbMallocRaw(sqlite3*, unsigned);
1772 char *sqlite3StrDup(const char*);
1773 char *sqlite3StrNDup(const char*, int);
1774 char *sqlite3DbStrDup(sqlite3*,const char*);
1775 char *sqlite3DbStrNDup(sqlite3*,const char*, int);
1776 void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
1777 void *sqlite3DbRealloc(sqlite3 *, void *, int);
1778 int sqlite3MallocSize(void *);
1779 
1780 char *sqlite3MPrintf(sqlite3*,const char*, ...);
1781 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
1782 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
1783   void sqlite3DebugPrintf(const char*, ...);
1784 #endif
1785 #if defined(SQLITE_TEST)
1786   void *sqlite3TextToPtr(const char*);
1787 #endif
1788 void sqlite3SetString(char **, ...);
1789 void sqlite3ErrorMsg(Parse*, const char*, ...);
1790 void sqlite3ErrorClear(Parse*);
1791 void sqlite3Dequote(char*);
1792 void sqlite3DequoteExpr(sqlite3*, Expr*);
1793 int sqlite3KeywordCode(const unsigned char*, int);
1794 int sqlite3RunParser(Parse*, const char*, char **);
1795 void sqlite3FinishCoding(Parse*);
1796 int sqlite3GetTempReg(Parse*);
1797 void sqlite3ReleaseTempReg(Parse*,int);
1798 int sqlite3GetTempRange(Parse*,int);
1799 void sqlite3ReleaseTempRange(Parse*,int,int);
1800 Expr *sqlite3Expr(sqlite3*, int, Expr*, Expr*, const Token*);
1801 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
1802 Expr *sqlite3RegisterExpr(Parse*,Token*);
1803 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
1804 void sqlite3ExprSpan(Expr*,Token*,Token*);
1805 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
1806 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
1807 void sqlite3ExprDelete(Expr*);
1808 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*,Token*);
1809 void sqlite3ExprListDelete(ExprList*);
1810 int sqlite3Init(sqlite3*, char**);
1811 int sqlite3InitCallback(void*, int, char**, char**);
1812 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
1813 void sqlite3ResetInternalSchema(sqlite3*, int);
1814 void sqlite3BeginParse(Parse*,int);
1815 void sqlite3CommitInternalChanges(sqlite3*);
1816 Table *sqlite3ResultSetOfSelect(Parse*,char*,Select*);
1817 void sqlite3OpenMasterTable(Parse *, int);
1818 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
1819 void sqlite3AddColumn(Parse*,Token*);
1820 void sqlite3AddNotNull(Parse*, int);
1821 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
1822 void sqlite3AddCheckConstraint(Parse*, Expr*);
1823 void sqlite3AddColumnType(Parse*,Token*);
1824 void sqlite3AddDefaultValue(Parse*,Expr*);
1825 void sqlite3AddCollateType(Parse*, Token*);
1826 void sqlite3EndTable(Parse*,Token*,Token*,Select*);
1827 
1828 Bitvec *sqlite3BitvecCreate(u32);
1829 int sqlite3BitvecTest(Bitvec*, u32);
1830 int sqlite3BitvecSet(Bitvec*, u32);
1831 void sqlite3BitvecClear(Bitvec*, u32);
1832 void sqlite3BitvecDestroy(Bitvec*);
1833 int sqlite3BitvecBuiltinTest(int,int*);
1834 
1835 void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
1836 
1837 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
1838   int sqlite3ViewGetColumnNames(Parse*,Table*);
1839 #else
1840 # define sqlite3ViewGetColumnNames(A,B) 0
1841 #endif
1842 
1843 void sqlite3DropTable(Parse*, SrcList*, int, int);
1844 void sqlite3DeleteTable(Table*);
1845 void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
1846 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int,int*,int*,int*);
1847 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
1848 int sqlite3IdListIndex(IdList*,const char*);
1849 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
1850 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*, Token*,
1851                                       Select*, Expr*, IdList*);
1852 void sqlite3SrcListShiftJoinType(SrcList*);
1853 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
1854 void sqlite3IdListDelete(IdList*);
1855 void sqlite3SrcListDelete(SrcList*);
1856 void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
1857                         Token*, int, int);
1858 void sqlite3DropIndex(Parse*, SrcList*, int);
1859 int sqlite3Select(Parse*, Select*, SelectDest*, Select*, int, int*, char *aff);
1860 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
1861                          Expr*,ExprList*,int,Expr*,Expr*);
1862 void sqlite3SelectDelete(Select*);
1863 Table *sqlite3SrcListLookup(Parse*, SrcList*);
1864 int sqlite3IsReadOnly(Parse*, Table*, int);
1865 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
1866 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
1867 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
1868 WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**, u8);
1869 void sqlite3WhereEnd(WhereInfo*);
1870 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, int);
1871 void sqlite3ExprCodeMove(Parse*, int, int);
1872 void sqlite3ExprClearColumnCache(Parse*, int);
1873 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
1874 int sqlite3ExprWritableRegister(Parse*,int,int);
1875 int sqlite3ExprCode(Parse*, Expr*, int);
1876 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
1877 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
1878 int sqlite3ExprCodeAndCache(Parse*, Expr*, int);
1879 void sqlite3ExprCodeConstants(Parse*, Expr*);
1880 int sqlite3ExprCodeExprList(Parse*, ExprList*, int);
1881 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
1882 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
1883 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
1884 Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
1885 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
1886 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
1887 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
1888 void sqlite3Vacuum(Parse*);
1889 int sqlite3RunVacuum(char**, sqlite3*);
1890 char *sqlite3NameFromToken(sqlite3*, Token*);
1891 int sqlite3ExprCompare(Expr*, Expr*);
1892 int sqlite3ExprResolveNames(NameContext *, Expr *);
1893 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
1894 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
1895 Vdbe *sqlite3GetVdbe(Parse*);
1896 Expr *sqlite3CreateIdExpr(Parse *, const char*);
1897 void sqlite3PrngSaveState(void);
1898 void sqlite3PrngRestoreState(void);
1899 void sqlite3PrngResetState(void);
1900 void sqlite3RollbackAll(sqlite3*);
1901 void sqlite3CodeVerifySchema(Parse*, int);
1902 void sqlite3BeginTransaction(Parse*, int);
1903 void sqlite3CommitTransaction(Parse*);
1904 void sqlite3RollbackTransaction(Parse*);
1905 int sqlite3ExprIsConstant(Expr*);
1906 int sqlite3ExprIsConstantNotJoin(Expr*);
1907 int sqlite3ExprIsConstantOrFunction(Expr*);
1908 int sqlite3ExprIsInteger(Expr*, int*);
1909 int sqlite3IsRowid(const char*);
1910 void sqlite3GenerateRowDelete(Parse*, Table*, int, int, int);
1911 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int*);
1912 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int);
1913 void sqlite3GenerateConstraintChecks(Parse*,Table*,int,int,
1914                                      int*,int,int,int,int);
1915 void sqlite3CompleteInsertion(Parse*, Table*, int, int, int*,int,int,int,int);
1916 int sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
1917 void sqlite3BeginWriteOperation(Parse*, int, int);
1918 Expr *sqlite3ExprDup(sqlite3*,Expr*);
1919 void sqlite3TokenCopy(sqlite3*,Token*, Token*);
1920 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*);
1921 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*);
1922 IdList *sqlite3IdListDup(sqlite3*,IdList*);
1923 Select *sqlite3SelectDup(sqlite3*,Select*);
1924 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);
1925 void sqlite3RegisterBuiltinFunctions(sqlite3*);
1926 void sqlite3RegisterDateTimeFunctions(sqlite3*);
1927 #ifdef SQLITE_DEBUG
1928   int sqlite3SafetyOn(sqlite3*);
1929   int sqlite3SafetyOff(sqlite3*);
1930 #else
1931 # define sqlite3SafetyOn(A) 0
1932 # define sqlite3SafetyOff(A) 0
1933 #endif
1934 int sqlite3SafetyCheckOk(sqlite3*);
1935 int sqlite3SafetyCheckSickOrOk(sqlite3*);
1936 void sqlite3ChangeCookie(Parse*, int);
1937 void sqlite3MaterializeView(Parse*, Select*, Expr*, u32, int);
1938 
1939 #ifndef SQLITE_OMIT_TRIGGER
1940   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
1941                            Expr*,int, int);
1942   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
1943   void sqlite3DropTrigger(Parse*, SrcList*, int);
1944   void sqlite3DropTriggerPtr(Parse*, Trigger*);
1945   int sqlite3TriggersExist(Parse*, Table*, int, ExprList*);
1946   int sqlite3CodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int,
1947                            int, int, u32*, u32*);
1948   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
1949   void sqlite3DeleteTriggerStep(TriggerStep*);
1950   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
1951   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
1952                                         ExprList*,Select*,int);
1953   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, int);
1954   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
1955   void sqlite3DeleteTrigger(Trigger*);
1956   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
1957   void sqlite3SelectMask(Parse *, Select *, u32);
1958 #else
1959 # define sqlite3TriggersExist(A,B,C,D,E,F) 0
1960 # define sqlite3DeleteTrigger(A)
1961 # define sqlite3DropTriggerPtr(A,B)
1962 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
1963 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I,J,K) 0
1964 # define sqlite3SelectMask(A, B, C)
1965 #endif
1966 
1967 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
1968 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
1969 void sqlite3DeferForeignKey(Parse*, int);
1970 #ifndef SQLITE_OMIT_AUTHORIZATION
1971   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
1972   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
1973   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
1974   void sqlite3AuthContextPop(AuthContext*);
1975 #else
1976 # define sqlite3AuthRead(a,b,c,d)
1977 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
1978 # define sqlite3AuthContextPush(a,b,c)
1979 # define sqlite3AuthContextPop(a)  ((void)(a))
1980 #endif
1981 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
1982 void sqlite3Detach(Parse*, Expr*);
1983 int sqlite3BtreeFactory(const sqlite3 *db, const char *zFilename,
1984                        int omitJournal, int nCache, int flags, Btree **ppBtree);
1985 int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
1986 int sqlite3FixSrcList(DbFixer*, SrcList*);
1987 int sqlite3FixSelect(DbFixer*, Select*);
1988 int sqlite3FixExpr(DbFixer*, Expr*);
1989 int sqlite3FixExprList(DbFixer*, ExprList*);
1990 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
1991 int sqlite3AtoF(const char *z, double*);
1992 char *sqlite3_snprintf(int,char*,const char*,...);
1993 int sqlite3GetInt32(const char *, int*);
1994 int sqlite3FitsIn64Bits(const char *, int);
1995 int sqlite3Utf16ByteLen(const void *pData, int nChar);
1996 int sqlite3Utf8CharLen(const char *pData, int nByte);
1997 int sqlite3Utf8Read(const u8*, const u8*, const u8**);
1998 int sqlite3PutVarint(unsigned char*, u64);
1999 int sqlite3PutVarint32(unsigned char*, u32);
2000 int sqlite3GetVarint(const unsigned char *, u64 *);
2001 int sqlite3GetVarint32(const unsigned char *, u32 *);
2002 int sqlite3VarintLen(u64 v);
2003 void sqlite3IndexAffinityStr(Vdbe *, Index *);
2004 void sqlite3TableAffinityStr(Vdbe *, Table *);
2005 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
2006 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
2007 char sqlite3ExprAffinity(Expr *pExpr);
2008 int sqlite3Atoi64(const char*, i64*);
2009 void sqlite3Error(sqlite3*, int, const char*,...);
2010 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
2011 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
2012 const char *sqlite3ErrStr(int);
2013 int sqlite3ReadSchema(Parse *pParse);
2014 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char *,int,int);
2015 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName, int nName);
2016 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
2017 Expr *sqlite3ExprSetColl(Parse *pParse, Expr *, Token *);
2018 int sqlite3CheckCollSeq(Parse *, CollSeq *);
2019 int sqlite3CheckObjectName(Parse *, const char *);
2020 void sqlite3VdbeSetChanges(sqlite3 *, int);
2021 
2022 const void *sqlite3ValueText(sqlite3_value*, u8);
2023 int sqlite3ValueBytes(sqlite3_value*, u8);
2024 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
2025                         void(*)(void*));
2026 void sqlite3ValueFree(sqlite3_value*);
2027 sqlite3_value *sqlite3ValueNew(sqlite3 *);
2028 char *sqlite3Utf16to8(sqlite3 *, const void*, int);
2029 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
2030 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
2031 #ifndef SQLITE_AMALGAMATION
2032 extern const unsigned char sqlite3UpperToLower[];
2033 #endif
2034 void sqlite3RootPageMoved(Db*, int, int);
2035 void sqlite3Reindex(Parse*, Token*, Token*);
2036 void sqlite3AlterFunctions(sqlite3*);
2037 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
2038 int sqlite3GetToken(const unsigned char *, int *);
2039 void sqlite3NestedParse(Parse*, const char*, ...);
2040 void sqlite3ExpirePreparedStatements(sqlite3*);
2041 void sqlite3CodeSubselect(Parse *, Expr *);
2042 int sqlite3SelectResolve(Parse *, Select *, NameContext *);
2043 void sqlite3ColumnDefault(Vdbe *, Table *, int);
2044 void sqlite3AlterFinishAddColumn(Parse *, Token *);
2045 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
2046 CollSeq *sqlite3GetCollSeq(sqlite3*, CollSeq *, const char *, int);
2047 char sqlite3AffinityType(const Token*);
2048 void sqlite3Analyze(Parse*, Token*, Token*);
2049 int sqlite3InvokeBusyHandler(BusyHandler*);
2050 int sqlite3FindDb(sqlite3*, Token*);
2051 int sqlite3AnalysisLoad(sqlite3*,int iDB);
2052 void sqlite3DefaultRowEst(Index*);
2053 void sqlite3RegisterLikeFunctions(sqlite3*, int);
2054 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
2055 void sqlite3AttachFunctions(sqlite3 *);
2056 void sqlite3MinimumFileFormat(Parse*, int, int);
2057 void sqlite3SchemaFree(void *);
2058 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
2059 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
2060 KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
2061 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
2062   void (*)(sqlite3_context*,int,sqlite3_value **),
2063   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*));
2064 int sqlite3ApiExit(sqlite3 *db, int);
2065 int sqlite3OpenTempDatabase(Parse *);
2066 
2067 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
2068 char *sqlite3StrAccumFinish(StrAccum*);
2069 void sqlite3StrAccumReset(StrAccum*);
2070 void sqlite3SelectDestInit(SelectDest*,int,int);
2071 
2072 /*
2073 ** The interface to the LEMON-generated parser
2074 */
2075 void *sqlite3ParserAlloc(void*(*)(size_t));
2076 void sqlite3ParserFree(void*, void(*)(void*));
2077 void sqlite3Parser(void*, int, Token, Parse*);
2078 
2079 int sqlite3AutoLoadExtensions(sqlite3*);
2080 #ifndef SQLITE_OMIT_LOAD_EXTENSION
2081   void sqlite3CloseExtensions(sqlite3*);
2082 #else
2083 # define sqlite3CloseExtensions(X)
2084 #endif
2085 
2086 #ifndef SQLITE_OMIT_SHARED_CACHE
2087   void sqlite3TableLock(Parse *, int, int, u8, const char *);
2088 #else
2089   #define sqlite3TableLock(v,w,x,y,z)
2090 #endif
2091 
2092 #ifdef SQLITE_TEST
2093   int sqlite3Utf8To8(unsigned char*);
2094 #endif
2095 
2096 #ifdef SQLITE_OMIT_VIRTUALTABLE
2097 #  define sqlite3VtabClear(X)
2098 #  define sqlite3VtabSync(X,Y) (Y)
2099 #  define sqlite3VtabRollback(X)
2100 #  define sqlite3VtabCommit(X)
2101 #else
2102    void sqlite3VtabClear(Table*);
2103    int sqlite3VtabSync(sqlite3 *db, int rc);
2104    int sqlite3VtabRollback(sqlite3 *db);
2105    int sqlite3VtabCommit(sqlite3 *db);
2106 #endif
2107 void sqlite3VtabLock(sqlite3_vtab*);
2108 void sqlite3VtabUnlock(sqlite3*, sqlite3_vtab*);
2109 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*);
2110 void sqlite3VtabFinishParse(Parse*, Token*);
2111 void sqlite3VtabArgInit(Parse*);
2112 void sqlite3VtabArgExtend(Parse*, Token*);
2113 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
2114 int sqlite3VtabCallConnect(Parse*, Table*);
2115 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
2116 int sqlite3VtabBegin(sqlite3 *, sqlite3_vtab *);
2117 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
2118 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
2119 int sqlite3Reprepare(Vdbe*);
2120 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
2121 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
2122 
2123 
2124 /*
2125 ** Available fault injectors.  Should be numbered beginning with 0.
2126 */
2127 #define SQLITE_FAULTINJECTOR_MALLOC     0
2128 #define SQLITE_FAULTINJECTOR_COUNT      1
2129 
2130 /*
2131 ** The interface to the fault injector subsystem.  If the fault injector
2132 ** mechanism is disabled at compile-time then set up macros so that no
2133 ** unnecessary code is generated.
2134 */
2135 #ifndef SQLITE_OMIT_BUILTIN_TEST
2136   void sqlite3FaultConfig(int,int,int);
2137   int sqlite3FaultFailures(int);
2138   int sqlite3FaultBenignFailures(int);
2139   int sqlite3FaultPending(int);
2140   void sqlite3FaultBenign(int,int);
2141   int sqlite3FaultStep(int);
2142 #else
2143 # define sqlite3FaultConfig(A,B,C)
2144 # define sqlite3FaultFailures(A)         0
2145 # define sqlite3FaultBenignFailures(A)   0
2146 # define sqlite3FaultPending(A)          (-1)
2147 # define sqlite3FaultBenign(A,B)
2148 # define sqlite3FaultStep(A)             0
2149 #endif
2150 
2151 
2152 
2153 #define IN_INDEX_ROWID           1
2154 #define IN_INDEX_EPH             2
2155 #define IN_INDEX_INDEX           3
2156 int sqlite3FindInIndex(Parse *, Expr *, int);
2157 
2158 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
2159   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
2160   int sqlite3JournalSize(sqlite3_vfs *);
2161   int sqlite3JournalCreate(sqlite3_file *);
2162 #else
2163   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
2164 #endif
2165 
2166 #if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
2167   void sqlite3ExprSetHeight(Expr *);
2168   int sqlite3SelectExprHeight(Select *);
2169 #else
2170   #define sqlite3ExprSetHeight(x)
2171 #endif
2172 
2173 u32 sqlite3Get4byte(const u8*);
2174 void sqlite3Put4byte(u8*, u32);
2175 
2176 #ifdef SQLITE_SSE
2177 #include "sseInt.h"
2178 #endif
2179 
2180 #ifdef SQLITE_DEBUG
2181   void sqlite3ParserTrace(FILE*, char *);
2182 #endif
2183 
2184 /*
2185 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
2186 ** sqlite3IoTrace is a pointer to a printf-like routine used to
2187 ** print I/O tracing messages.
2188 */
2189 #ifdef SQLITE_ENABLE_IOTRACE
2190 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
2191   void sqlite3VdbeIOTraceSql(Vdbe*);
2192 #else
2193 # define IOTRACE(A)
2194 # define sqlite3VdbeIOTraceSql(X)
2195 #endif
2196 SQLITE_EXTERN void (*sqlite3IoTrace)(const char*,...);
2197 
2198 #endif
2199