xref: /sqlite-3.40.0/src/sqliteInt.h (revision 5130c31b)
1 /*
2 ** 2001 September 15
3 **
4 ** The author disclaims copyright to this source code.  In place of
5 ** a legal notice, here is a blessing:
6 **
7 **    May you do good and not evil.
8 **    May you find forgiveness for yourself and forgive others.
9 **    May you share freely, never taking more than you give.
10 **
11 *************************************************************************
12 ** Internal interface definitions for SQLite.
13 **
14 */
15 #ifndef _SQLITEINT_H_
16 #define _SQLITEINT_H_
17 
18 /*
19 ** These #defines should enable >2GB file support on POSIX if the
20 ** underlying operating system supports it.  If the OS lacks
21 ** large file support, or if the OS is windows, these should be no-ops.
22 **
23 ** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
24 ** system #includes.  Hence, this block of code must be the very first
25 ** code in all source files.
26 **
27 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
28 ** on the compiler command line.  This is necessary if you are compiling
29 ** on a recent machine (ex: Red Hat 7.2) but you want your code to work
30 ** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
31 ** without this option, LFS is enable.  But LFS does not exist in the kernel
32 ** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
33 ** portability you should omit LFS.
34 **
35 ** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
36 */
37 #ifndef SQLITE_DISABLE_LFS
38 # define _LARGE_FILE       1
39 # ifndef _FILE_OFFSET_BITS
40 #   define _FILE_OFFSET_BITS 64
41 # endif
42 # define _LARGEFILE_SOURCE 1
43 #endif
44 
45 /*
46 ** Include the configuration header output by 'configure' if we're using the
47 ** autoconf-based build
48 */
49 #ifdef _HAVE_SQLITE_CONFIG_H
50 #include "config.h"
51 #endif
52 
53 #include "sqliteLimit.h"
54 
55 /* Disable nuisance warnings on Borland compilers */
56 #if defined(__BORLANDC__)
57 #pragma warn -rch /* unreachable code */
58 #pragma warn -ccc /* Condition is always true or false */
59 #pragma warn -aus /* Assigned value is never used */
60 #pragma warn -csu /* Comparing signed and unsigned */
61 #pragma warn -spa /* Suspicious pointer arithmetic */
62 #endif
63 
64 /* Needed for various definitions... */
65 #ifndef _GNU_SOURCE
66 # define _GNU_SOURCE
67 #endif
68 
69 /*
70 ** Include standard header files as necessary
71 */
72 #ifdef HAVE_STDINT_H
73 #include <stdint.h>
74 #endif
75 #ifdef HAVE_INTTYPES_H
76 #include <inttypes.h>
77 #endif
78 
79 /*
80 ** The number of samples of an index that SQLite takes in order to
81 ** construct a histogram of the table content when running ANALYZE
82 ** and with SQLITE_ENABLE_STAT2
83 */
84 #define SQLITE_INDEX_SAMPLES 10
85 
86 /*
87 ** The following macros are used to cast pointers to integers and
88 ** integers to pointers.  The way you do this varies from one compiler
89 ** to the next, so we have developed the following set of #if statements
90 ** to generate appropriate macros for a wide range of compilers.
91 **
92 ** The correct "ANSI" way to do this is to use the intptr_t type.
93 ** Unfortunately, that typedef is not available on all compilers, or
94 ** if it is available, it requires an #include of specific headers
95 ** that vary from one machine to the next.
96 **
97 ** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
98 ** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
99 ** So we have to define the macros in different ways depending on the
100 ** compiler.
101 */
102 #if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
103 # define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
104 # define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
105 #elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
106 # define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
107 # define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
108 #elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
109 # define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
110 # define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
111 #else                          /* Generates a warning - but it always works */
112 # define SQLITE_INT_TO_PTR(X)  ((void*)(X))
113 # define SQLITE_PTR_TO_INT(X)  ((int)(X))
114 #endif
115 
116 /*
117 ** The SQLITE_THREADSAFE macro must be defined as either 0 or 1.
118 ** Older versions of SQLite used an optional THREADSAFE macro.
119 ** We support that for legacy
120 */
121 #if !defined(SQLITE_THREADSAFE)
122 #if defined(THREADSAFE)
123 # define SQLITE_THREADSAFE THREADSAFE
124 #else
125 # define SQLITE_THREADSAFE 1
126 #endif
127 #endif
128 
129 /*
130 ** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
131 ** It determines whether or not the features related to
132 ** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
133 ** be overridden at runtime using the sqlite3_config() API.
134 */
135 #if !defined(SQLITE_DEFAULT_MEMSTATUS)
136 # define SQLITE_DEFAULT_MEMSTATUS 1
137 #endif
138 
139 /*
140 ** Exactly one of the following macros must be defined in order to
141 ** specify which memory allocation subsystem to use.
142 **
143 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
144 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
145 **
146 ** (Historical note:  There used to be several other options, but we've
147 ** pared it down to just these two.)
148 **
149 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
150 ** the default.
151 */
152 #if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_MEMDEBUG)>1
153 # error "At most one of the following compile-time configuration options\
154  is allows: SQLITE_SYSTEM_MALLOC, SQLITE_MEMDEBUG"
155 #endif
156 #if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_MEMDEBUG)==0
157 # define SQLITE_SYSTEM_MALLOC 1
158 #endif
159 
160 /*
161 ** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
162 ** sizes of memory allocations below this value where possible.
163 */
164 #if !defined(SQLITE_MALLOC_SOFT_LIMIT)
165 # define SQLITE_MALLOC_SOFT_LIMIT 1024
166 #endif
167 
168 /*
169 ** We need to define _XOPEN_SOURCE as follows in order to enable
170 ** recursive mutexes on most Unix systems.  But Mac OS X is different.
171 ** The _XOPEN_SOURCE define causes problems for Mac OS X we are told,
172 ** so it is omitted there.  See ticket #2673.
173 **
174 ** Later we learn that _XOPEN_SOURCE is poorly or incorrectly
175 ** implemented on some systems.  So we avoid defining it at all
176 ** if it is already defined or if it is unneeded because we are
177 ** not doing a threadsafe build.  Ticket #2681.
178 **
179 ** See also ticket #2741.
180 */
181 #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE
182 #  define _XOPEN_SOURCE 500  /* Needed to enable pthread recursive mutexes */
183 #endif
184 
185 /*
186 ** The TCL headers are only needed when compiling the TCL bindings.
187 */
188 #if defined(SQLITE_TCL) || defined(TCLSH)
189 # include <tcl.h>
190 #endif
191 
192 /*
193 ** Many people are failing to set -DNDEBUG=1 when compiling SQLite.
194 ** Setting NDEBUG makes the code smaller and run faster.  So the following
195 ** lines are added to automatically set NDEBUG unless the -DSQLITE_DEBUG=1
196 ** option is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
197 ** feature.
198 */
199 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
200 # define NDEBUG 1
201 #endif
202 
203 /*
204 ** The testcase() macro is used to aid in coverage testing.  When
205 ** doing coverage testing, the condition inside the argument to
206 ** testcase() must be evaluated both true and false in order to
207 ** get full branch coverage.  The testcase() macro is inserted
208 ** to help ensure adequate test coverage in places where simple
209 ** condition/decision coverage is inadequate.  For example, testcase()
210 ** can be used to make sure boundary values are tested.  For
211 ** bitmask tests, testcase() can be used to make sure each bit
212 ** is significant and used at least once.  On switch statements
213 ** where multiple cases go to the same block of code, testcase()
214 ** can insure that all cases are evaluated.
215 **
216 */
217 #ifdef SQLITE_COVERAGE_TEST
218   void sqlite3Coverage(int);
219 # define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
220 #else
221 # define testcase(X)
222 #endif
223 
224 /*
225 ** The TESTONLY macro is used to enclose variable declarations or
226 ** other bits of code that are needed to support the arguments
227 ** within testcase() and assert() macros.
228 */
229 #if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
230 # define TESTONLY(X)  X
231 #else
232 # define TESTONLY(X)
233 #endif
234 
235 /*
236 ** Sometimes we need a small amount of code such as a variable initialization
237 ** to setup for a later assert() statement.  We do not want this code to
238 ** appear when assert() is disabled.  The following macro is therefore
239 ** used to contain that setup code.  The "VVA" acronym stands for
240 ** "Verification, Validation, and Accreditation".  In other words, the
241 ** code within VVA_ONLY() will only run during verification processes.
242 */
243 #ifndef NDEBUG
244 # define VVA_ONLY(X)  X
245 #else
246 # define VVA_ONLY(X)
247 #endif
248 
249 /*
250 ** The ALWAYS and NEVER macros surround boolean expressions which
251 ** are intended to always be true or false, respectively.  Such
252 ** expressions could be omitted from the code completely.  But they
253 ** are included in a few cases in order to enhance the resilience
254 ** of SQLite to unexpected behavior - to make the code "self-healing"
255 ** or "ductile" rather than being "brittle" and crashing at the first
256 ** hint of unplanned behavior.
257 **
258 ** In other words, ALWAYS and NEVER are added for defensive code.
259 **
260 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
261 ** be true and false so that the unreachable code then specify will
262 ** not be counted as untested code.
263 */
264 #if defined(SQLITE_COVERAGE_TEST)
265 # define ALWAYS(X)      (1)
266 # define NEVER(X)       (0)
267 #elif !defined(NDEBUG)
268 # define ALWAYS(X)      ((X)?1:(assert(0),0))
269 # define NEVER(X)       ((X)?(assert(0),1):0)
270 #else
271 # define ALWAYS(X)      (X)
272 # define NEVER(X)       (X)
273 #endif
274 
275 /*
276 ** The macro unlikely() is a hint that surrounds a boolean
277 ** expression that is usually false.  Macro likely() surrounds
278 ** a boolean expression that is usually true.  GCC is able to
279 ** use these hints to generate better code, sometimes.
280 */
281 #if defined(__GNUC__) && 0
282 # define likely(X)    __builtin_expect((X),1)
283 # define unlikely(X)  __builtin_expect((X),0)
284 #else
285 # define likely(X)    !!(X)
286 # define unlikely(X)  !!(X)
287 #endif
288 
289 #include "sqlite3.h"
290 #include "hash.h"
291 #include "parse.h"
292 #include <stdio.h>
293 #include <stdlib.h>
294 #include <string.h>
295 #include <assert.h>
296 #include <stddef.h>
297 
298 /*
299 ** If compiling for a processor that lacks floating point support,
300 ** substitute integer for floating-point
301 */
302 #ifdef SQLITE_OMIT_FLOATING_POINT
303 # define double sqlite_int64
304 # define float sqlite_int64
305 # define LONGDOUBLE_TYPE sqlite_int64
306 # ifndef SQLITE_BIG_DBL
307 #   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
308 # endif
309 # define SQLITE_OMIT_DATETIME_FUNCS 1
310 # define SQLITE_OMIT_TRACE 1
311 # undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
312 # undef SQLITE_HAVE_ISNAN
313 #endif
314 #ifndef SQLITE_BIG_DBL
315 # define SQLITE_BIG_DBL (1e99)
316 #endif
317 
318 /*
319 ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
320 ** afterward. Having this macro allows us to cause the C compiler
321 ** to omit code used by TEMP tables without messy #ifndef statements.
322 */
323 #ifdef SQLITE_OMIT_TEMPDB
324 #define OMIT_TEMPDB 1
325 #else
326 #define OMIT_TEMPDB 0
327 #endif
328 
329 /*
330 ** The "file format" number is an integer that is incremented whenever
331 ** the VDBE-level file format changes.  The following macros define the
332 ** the default file format for new databases and the maximum file format
333 ** that the library can read.
334 */
335 #define SQLITE_MAX_FILE_FORMAT 4
336 #ifndef SQLITE_DEFAULT_FILE_FORMAT
337 # define SQLITE_DEFAULT_FILE_FORMAT 1
338 #endif
339 
340 /*
341 ** Determine whether triggers are recursive by default.  This can be
342 ** changed at run-time using a pragma.
343 */
344 #ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
345 # define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
346 #endif
347 
348 /*
349 ** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
350 ** on the command-line
351 */
352 #ifndef SQLITE_TEMP_STORE
353 # define SQLITE_TEMP_STORE 1
354 #endif
355 
356 /*
357 ** GCC does not define the offsetof() macro so we'll have to do it
358 ** ourselves.
359 */
360 #ifndef offsetof
361 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
362 #endif
363 
364 /*
365 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
366 ** not, there are still machines out there that use EBCDIC.)
367 */
368 #if 'A' == '\301'
369 # define SQLITE_EBCDIC 1
370 #else
371 # define SQLITE_ASCII 1
372 #endif
373 
374 /*
375 ** Integers of known sizes.  These typedefs might change for architectures
376 ** where the sizes very.  Preprocessor macros are available so that the
377 ** types can be conveniently redefined at compile-type.  Like this:
378 **
379 **         cc '-DUINTPTR_TYPE=long long int' ...
380 */
381 #ifndef UINT32_TYPE
382 # ifdef HAVE_UINT32_T
383 #  define UINT32_TYPE uint32_t
384 # else
385 #  define UINT32_TYPE unsigned int
386 # endif
387 #endif
388 #ifndef UINT16_TYPE
389 # ifdef HAVE_UINT16_T
390 #  define UINT16_TYPE uint16_t
391 # else
392 #  define UINT16_TYPE unsigned short int
393 # endif
394 #endif
395 #ifndef INT16_TYPE
396 # ifdef HAVE_INT16_T
397 #  define INT16_TYPE int16_t
398 # else
399 #  define INT16_TYPE short int
400 # endif
401 #endif
402 #ifndef UINT8_TYPE
403 # ifdef HAVE_UINT8_T
404 #  define UINT8_TYPE uint8_t
405 # else
406 #  define UINT8_TYPE unsigned char
407 # endif
408 #endif
409 #ifndef INT8_TYPE
410 # ifdef HAVE_INT8_T
411 #  define INT8_TYPE int8_t
412 # else
413 #  define INT8_TYPE signed char
414 # endif
415 #endif
416 #ifndef LONGDOUBLE_TYPE
417 # define LONGDOUBLE_TYPE long double
418 #endif
419 typedef sqlite_int64 i64;          /* 8-byte signed integer */
420 typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
421 typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
422 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
423 typedef INT16_TYPE i16;            /* 2-byte signed integer */
424 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
425 typedef INT8_TYPE i8;              /* 1-byte signed integer */
426 
427 /*
428 ** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
429 ** that can be stored in a u32 without loss of data.  The value
430 ** is 0x00000000ffffffff.  But because of quirks of some compilers, we
431 ** have to specify the value in the less intuitive manner shown:
432 */
433 #define SQLITE_MAX_U32  ((((u64)1)<<32)-1)
434 
435 /*
436 ** Macros to determine whether the machine is big or little endian,
437 ** evaluated at runtime.
438 */
439 #ifdef SQLITE_AMALGAMATION
440 const int sqlite3one = 1;
441 #else
442 extern const int sqlite3one;
443 #endif
444 #if defined(i386) || defined(__i386__) || defined(_M_IX86)\
445                              || defined(__x86_64) || defined(__x86_64__)
446 # define SQLITE_BIGENDIAN    0
447 # define SQLITE_LITTLEENDIAN 1
448 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
449 #else
450 # define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
451 # define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
452 # define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
453 #endif
454 
455 /*
456 ** Constants for the largest and smallest possible 64-bit signed integers.
457 ** These macros are designed to work correctly on both 32-bit and 64-bit
458 ** compilers.
459 */
460 #define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
461 #define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
462 
463 /*
464 ** Round up a number to the next larger multiple of 8.  This is used
465 ** to force 8-byte alignment on 64-bit architectures.
466 */
467 #define ROUND8(x)     (((x)+7)&~7)
468 
469 /*
470 ** Round down to the nearest multiple of 8
471 */
472 #define ROUNDDOWN8(x) ((x)&~7)
473 
474 /*
475 ** Assert that the pointer X is aligned to an 8-byte boundary.  This
476 ** macro is used only within assert() to verify that the code gets
477 ** all alignment restrictions correct.
478 **
479 ** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
480 ** underlying malloc() implemention might return us 4-byte aligned
481 ** pointers.  In that case, only verify 4-byte alignment.
482 */
483 #ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
484 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&3)==0)
485 #else
486 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
487 #endif
488 
489 
490 /*
491 ** An instance of the following structure is used to store the busy-handler
492 ** callback for a given sqlite handle.
493 **
494 ** The sqlite.busyHandler member of the sqlite struct contains the busy
495 ** callback for the database handle. Each pager opened via the sqlite
496 ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
497 ** callback is currently invoked only from within pager.c.
498 */
499 typedef struct BusyHandler BusyHandler;
500 struct BusyHandler {
501   int (*xFunc)(void *,int);  /* The busy callback */
502   void *pArg;                /* First arg to busy callback */
503   int nBusy;                 /* Incremented with each busy call */
504 };
505 
506 /*
507 ** Name of the master database table.  The master database table
508 ** is a special table that holds the names and attributes of all
509 ** user tables and indices.
510 */
511 #define MASTER_NAME       "sqlite_master"
512 #define TEMP_MASTER_NAME  "sqlite_temp_master"
513 
514 /*
515 ** The root-page of the master database table.
516 */
517 #define MASTER_ROOT       1
518 
519 /*
520 ** The name of the schema table.
521 */
522 #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
523 
524 /*
525 ** A convenience macro that returns the number of elements in
526 ** an array.
527 */
528 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
529 
530 /*
531 ** The following value as a destructor means to use sqlite3DbFree().
532 ** This is an internal extension to SQLITE_STATIC and SQLITE_TRANSIENT.
533 */
534 #define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3DbFree)
535 
536 /*
537 ** When SQLITE_OMIT_WSD is defined, it means that the target platform does
538 ** not support Writable Static Data (WSD) such as global and static variables.
539 ** All variables must either be on the stack or dynamically allocated from
540 ** the heap.  When WSD is unsupported, the variable declarations scattered
541 ** throughout the SQLite code must become constants instead.  The SQLITE_WSD
542 ** macro is used for this purpose.  And instead of referencing the variable
543 ** directly, we use its constant as a key to lookup the run-time allocated
544 ** buffer that holds real variable.  The constant is also the initializer
545 ** for the run-time allocated buffer.
546 **
547 ** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
548 ** macros become no-ops and have zero performance impact.
549 */
550 #ifdef SQLITE_OMIT_WSD
551   #define SQLITE_WSD const
552   #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
553   #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
554   int sqlite3_wsd_init(int N, int J);
555   void *sqlite3_wsd_find(void *K, int L);
556 #else
557   #define SQLITE_WSD
558   #define GLOBAL(t,v) v
559   #define sqlite3GlobalConfig sqlite3Config
560 #endif
561 
562 /*
563 ** The following macros are used to suppress compiler warnings and to
564 ** make it clear to human readers when a function parameter is deliberately
565 ** left unused within the body of a function. This usually happens when
566 ** a function is called via a function pointer. For example the
567 ** implementation of an SQL aggregate step callback may not use the
568 ** parameter indicating the number of arguments passed to the aggregate,
569 ** if it knows that this is enforced elsewhere.
570 **
571 ** When a function parameter is not used at all within the body of a function,
572 ** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
573 ** However, these macros may also be used to suppress warnings related to
574 ** parameters that may or may not be used depending on compilation options.
575 ** For example those parameters only used in assert() statements. In these
576 ** cases the parameters are named as per the usual conventions.
577 */
578 #define UNUSED_PARAMETER(x) (void)(x)
579 #define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
580 
581 /*
582 ** Forward references to structures
583 */
584 typedef struct AggInfo AggInfo;
585 typedef struct AuthContext AuthContext;
586 typedef struct AutoincInfo AutoincInfo;
587 typedef struct Bitvec Bitvec;
588 typedef struct CollSeq CollSeq;
589 typedef struct Column Column;
590 typedef struct Db Db;
591 typedef struct Schema Schema;
592 typedef struct Expr Expr;
593 typedef struct ExprList ExprList;
594 typedef struct ExprSpan ExprSpan;
595 typedef struct FKey FKey;
596 typedef struct FuncDef FuncDef;
597 typedef struct FuncDefHash FuncDefHash;
598 typedef struct IdList IdList;
599 typedef struct Index Index;
600 typedef struct IndexSample IndexSample;
601 typedef struct KeyClass KeyClass;
602 typedef struct KeyInfo KeyInfo;
603 typedef struct Lookaside Lookaside;
604 typedef struct LookasideSlot LookasideSlot;
605 typedef struct Module Module;
606 typedef struct NameContext NameContext;
607 typedef struct Parse Parse;
608 typedef struct RowSet RowSet;
609 typedef struct Savepoint Savepoint;
610 typedef struct Select Select;
611 typedef struct SrcList SrcList;
612 typedef struct StrAccum StrAccum;
613 typedef struct Table Table;
614 typedef struct TableLock TableLock;
615 typedef struct Token Token;
616 typedef struct Trigger Trigger;
617 typedef struct TriggerPrg TriggerPrg;
618 typedef struct TriggerStep TriggerStep;
619 typedef struct UnpackedRecord UnpackedRecord;
620 typedef struct VTable VTable;
621 typedef struct Walker Walker;
622 typedef struct WherePlan WherePlan;
623 typedef struct WhereInfo WhereInfo;
624 typedef struct WhereLevel WhereLevel;
625 
626 /*
627 ** Defer sourcing vdbe.h and btree.h until after the "u8" and
628 ** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
629 ** pointer types (i.e. FuncDef) defined above.
630 */
631 #include "btree.h"
632 #include "vdbe.h"
633 #include "pager.h"
634 #include "pcache.h"
635 
636 #include "os.h"
637 #include "mutex.h"
638 
639 
640 /*
641 ** Each database file to be accessed by the system is an instance
642 ** of the following structure.  There are normally two of these structures
643 ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
644 ** aDb[1] is the database file used to hold temporary tables.  Additional
645 ** databases may be attached.
646 */
647 struct Db {
648   char *zName;         /* Name of this database */
649   Btree *pBt;          /* The B*Tree structure for this database file */
650   u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
651   u8 safety_level;     /* How aggressive at syncing data to disk */
652   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
653 };
654 
655 /*
656 ** An instance of the following structure stores a database schema.
657 **
658 ** If there are no virtual tables configured in this schema, the
659 ** Schema.db variable is set to NULL. After the first virtual table
660 ** has been added, it is set to point to the database connection
661 ** used to create the connection. Once a virtual table has been
662 ** added to the Schema structure and the Schema.db variable populated,
663 ** only that database connection may use the Schema to prepare
664 ** statements.
665 */
666 struct Schema {
667   int schema_cookie;   /* Database schema version number for this file */
668   Hash tblHash;        /* All tables indexed by name */
669   Hash idxHash;        /* All (named) indices indexed by name */
670   Hash trigHash;       /* All triggers indexed by name */
671   Hash fkeyHash;       /* All foreign keys by referenced table name */
672   Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
673   u8 file_format;      /* Schema format version for this file */
674   u8 enc;              /* Text encoding used by this database */
675   u16 flags;           /* Flags associated with this schema */
676   int cache_size;      /* Number of pages to use in the cache */
677 #ifndef SQLITE_OMIT_VIRTUALTABLE
678   sqlite3 *db;         /* "Owner" connection. See comment above */
679 #endif
680 };
681 
682 /*
683 ** These macros can be used to test, set, or clear bits in the
684 ** Db.pSchema->flags field.
685 */
686 #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->flags&(P))==(P))
687 #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->flags&(P))!=0)
688 #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->flags|=(P)
689 #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->flags&=~(P)
690 
691 /*
692 ** Allowed values for the DB.pSchema->flags field.
693 **
694 ** The DB_SchemaLoaded flag is set after the database schema has been
695 ** read into internal hash tables.
696 **
697 ** DB_UnresetViews means that one or more views have column names that
698 ** have been filled out.  If the schema changes, these column names might
699 ** changes and so the view will need to be reset.
700 */
701 #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
702 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
703 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
704 
705 /*
706 ** The number of different kinds of things that can be limited
707 ** using the sqlite3_limit() interface.
708 */
709 #define SQLITE_N_LIMIT (SQLITE_LIMIT_TRIGGER_DEPTH+1)
710 
711 /*
712 ** Lookaside malloc is a set of fixed-size buffers that can be used
713 ** to satisfy small transient memory allocation requests for objects
714 ** associated with a particular database connection.  The use of
715 ** lookaside malloc provides a significant performance enhancement
716 ** (approx 10%) by avoiding numerous malloc/free requests while parsing
717 ** SQL statements.
718 **
719 ** The Lookaside structure holds configuration information about the
720 ** lookaside malloc subsystem.  Each available memory allocation in
721 ** the lookaside subsystem is stored on a linked list of LookasideSlot
722 ** objects.
723 **
724 ** Lookaside allocations are only allowed for objects that are associated
725 ** with a particular database connection.  Hence, schema information cannot
726 ** be stored in lookaside because in shared cache mode the schema information
727 ** is shared by multiple database connections.  Therefore, while parsing
728 ** schema information, the Lookaside.bEnabled flag is cleared so that
729 ** lookaside allocations are not used to construct the schema objects.
730 */
731 struct Lookaside {
732   u16 sz;                 /* Size of each buffer in bytes */
733   u8 bEnabled;            /* False to disable new lookaside allocations */
734   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
735   int nOut;               /* Number of buffers currently checked out */
736   int mxOut;              /* Highwater mark for nOut */
737   LookasideSlot *pFree;   /* List of available buffers */
738   void *pStart;           /* First byte of available memory space */
739   void *pEnd;             /* First byte past end of available space */
740 };
741 struct LookasideSlot {
742   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
743 };
744 
745 /*
746 ** A hash table for function definitions.
747 **
748 ** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
749 ** Collisions are on the FuncDef.pHash chain.
750 */
751 struct FuncDefHash {
752   FuncDef *a[23];       /* Hash table for functions */
753 };
754 
755 /*
756 ** Each database connection is an instance of the following structure.
757 **
758 ** The sqlite.lastRowid records the last insert rowid generated by an
759 ** insert statement.  Inserts on views do not affect its value.  Each
760 ** trigger has its own context, so that lastRowid can be updated inside
761 ** triggers as usual.  The previous value will be restored once the trigger
762 ** exits.  Upon entering a before or instead of trigger, lastRowid is no
763 ** longer (since after version 2.8.12) reset to -1.
764 **
765 ** The sqlite.nChange does not count changes within triggers and keeps no
766 ** context.  It is reset at start of sqlite3_exec.
767 ** The sqlite.lsChange represents the number of changes made by the last
768 ** insert, update, or delete statement.  It remains constant throughout the
769 ** length of a statement and is then updated by OP_SetCounts.  It keeps a
770 ** context stack just like lastRowid so that the count of changes
771 ** within a trigger is not seen outside the trigger.  Changes to views do not
772 ** affect the value of lsChange.
773 ** The sqlite.csChange keeps track of the number of current changes (since
774 ** the last statement) and is used to update sqlite_lsChange.
775 **
776 ** The member variables sqlite.errCode, sqlite.zErrMsg and sqlite.zErrMsg16
777 ** store the most recent error code and, if applicable, string. The
778 ** internal function sqlite3Error() is used to set these variables
779 ** consistently.
780 */
781 struct sqlite3 {
782   sqlite3_vfs *pVfs;            /* OS Interface */
783   int nDb;                      /* Number of backends currently in use */
784   Db *aDb;                      /* All backends */
785   int flags;                    /* Miscellaneous flags. See below */
786   int openFlags;                /* Flags passed to sqlite3_vfs.xOpen() */
787   int errCode;                  /* Most recent error code (SQLITE_*) */
788   int errMask;                  /* & result codes with this before returning */
789   u8 autoCommit;                /* The auto-commit flag. */
790   u8 temp_store;                /* 1: file 2: memory 0: default */
791   u8 mallocFailed;              /* True if we have seen a malloc failure */
792   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
793   u8 dfltJournalMode;           /* Default journal mode for attached dbs */
794   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
795   u8 suppressErr;               /* Do not issue error messages if true */
796   int nextPagesize;             /* Pagesize after VACUUM if >0 */
797   int nTable;                   /* Number of tables in the database */
798   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
799   i64 lastRowid;                /* ROWID of most recent insert (see above) */
800   u32 magic;                    /* Magic number for detect library misuse */
801   int nChange;                  /* Value returned by sqlite3_changes() */
802   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
803   sqlite3_mutex *mutex;         /* Connection mutex */
804   int aLimit[SQLITE_N_LIMIT];   /* Limits */
805   struct sqlite3InitInfo {      /* Information used during initialization */
806     int iDb;                    /* When back is being initialized */
807     int newTnum;                /* Rootpage of table being initialized */
808     u8 busy;                    /* TRUE if currently initializing */
809     u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
810   } init;
811   int nExtension;               /* Number of loaded extensions */
812   void **aExtension;            /* Array of shared library handles */
813   struct Vdbe *pVdbe;           /* List of active virtual machines */
814   int activeVdbeCnt;            /* Number of VDBEs currently executing */
815   int writeVdbeCnt;             /* Number of active VDBEs that are writing */
816   void (*xTrace)(void*,const char*);        /* Trace function */
817   void *pTraceArg;                          /* Argument to the trace function */
818   void (*xProfile)(void*,const char*,u64);  /* Profiling function */
819   void *pProfileArg;                        /* Argument to profile function */
820   void *pCommitArg;                 /* Argument to xCommitCallback() */
821   int (*xCommitCallback)(void*);    /* Invoked at every commit. */
822   void *pRollbackArg;               /* Argument to xRollbackCallback() */
823   void (*xRollbackCallback)(void*); /* Invoked at every commit. */
824   void *pUpdateArg;
825   void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
826 #ifndef SQLITE_OMIT_WAL
827   int (*xWalCallback)(void *, sqlite3 *, const char *, int);
828   void *pWalArg;
829 #endif
830   void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
831   void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
832   void *pCollNeededArg;
833   sqlite3_value *pErr;          /* Most recent error message */
834   char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
835   char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
836   union {
837     volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
838     double notUsed1;            /* Spacer */
839   } u1;
840   Lookaside lookaside;          /* Lookaside malloc configuration */
841 #ifndef SQLITE_OMIT_AUTHORIZATION
842   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
843                                 /* Access authorization function */
844   void *pAuthArg;               /* 1st argument to the access auth function */
845 #endif
846 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
847   int (*xProgress)(void *);     /* The progress callback */
848   void *pProgressArg;           /* Argument to the progress callback */
849   int nProgressOps;             /* Number of opcodes for progress callback */
850 #endif
851 #ifndef SQLITE_OMIT_VIRTUALTABLE
852   Hash aModule;                 /* populated by sqlite3_create_module() */
853   Table *pVTab;                 /* vtab with active Connect/Create method */
854   VTable **aVTrans;             /* Virtual tables with open transactions */
855   int nVTrans;                  /* Allocated size of aVTrans */
856   VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
857 #endif
858   FuncDefHash aFunc;            /* Hash table of connection functions */
859   Hash aCollSeq;                /* All collating sequences */
860   BusyHandler busyHandler;      /* Busy callback */
861   int busyTimeout;              /* Busy handler timeout, in msec */
862   Db aDbStatic[2];              /* Static space for the 2 default backends */
863   Savepoint *pSavepoint;        /* List of active savepoints */
864   int nSavepoint;               /* Number of non-transaction savepoints */
865   int nStatement;               /* Number of nested statement-transactions  */
866   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
867   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
868 
869 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
870   /* The following variables are all protected by the STATIC_MASTER
871   ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
872   **
873   ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
874   ** unlock so that it can proceed.
875   **
876   ** When X.pBlockingConnection==Y, that means that something that X tried
877   ** tried to do recently failed with an SQLITE_LOCKED error due to locks
878   ** held by Y.
879   */
880   sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
881   sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
882   void *pUnlockArg;                     /* Argument to xUnlockNotify */
883   void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
884   sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
885 #endif
886 };
887 
888 /*
889 ** A macro to discover the encoding of a database.
890 */
891 #define ENC(db) ((db)->aDb[0].pSchema->enc)
892 
893 /*
894 ** Possible values for the sqlite3.flags.
895 */
896 #define SQLITE_VdbeTrace      0x00000100  /* True to trace VDBE execution */
897 #define SQLITE_InternChanges  0x00000200  /* Uncommitted Hash table changes */
898 #define SQLITE_FullColNames   0x00000400  /* Show full column names on SELECT */
899 #define SQLITE_ShortColNames  0x00000800  /* Show short columns names */
900 #define SQLITE_CountRows      0x00001000  /* Count rows changed by INSERT, */
901                                           /*   DELETE, or UPDATE and return */
902                                           /*   the count using a callback. */
903 #define SQLITE_NullCallback   0x00002000  /* Invoke the callback once if the */
904                                           /*   result set is empty */
905 #define SQLITE_SqlTrace       0x00004000  /* Debug print SQL as it executes */
906 #define SQLITE_VdbeListing    0x00008000  /* Debug listings of VDBE programs */
907 #define SQLITE_WriteSchema    0x00010000  /* OK to update SQLITE_MASTER */
908 #define SQLITE_NoReadlock     0x00020000  /* Readlocks are omitted when
909                                           ** accessing read-only databases */
910 #define SQLITE_IgnoreChecks   0x00040000  /* Do not enforce check constraints */
911 #define SQLITE_ReadUncommitted 0x0080000  /* For shared-cache mode */
912 #define SQLITE_LegacyFileFmt  0x00100000  /* Create new databases in format 1 */
913 #define SQLITE_FullFSync      0x00200000  /* Use full fsync on the backend */
914 #define SQLITE_LoadExtension  0x00400000  /* Enable load_extension */
915 #define SQLITE_RecoveryMode   0x00800000  /* Ignore schema errors */
916 #define SQLITE_ReverseOrder   0x01000000  /* Reverse unordered SELECTs */
917 #define SQLITE_RecTriggers    0x02000000  /* Enable recursive triggers */
918 #define SQLITE_ForeignKeys    0x04000000  /* Enforce foreign key constraints  */
919 #define SQLITE_AutoIndex      0x08000000  /* Enable automatic indexes */
920 #define SQLITE_PreferBuiltin  0x10000000  /* Preference to built-in funcs */
921 
922 /*
923 ** Bits of the sqlite3.flags field that are used by the
924 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface.
925 ** These must be the low-order bits of the flags field.
926 */
927 #define SQLITE_QueryFlattener 0x01        /* Disable query flattening */
928 #define SQLITE_ColumnCache    0x02        /* Disable the column cache */
929 #define SQLITE_IndexSort      0x04        /* Disable indexes for sorting */
930 #define SQLITE_IndexSearch    0x08        /* Disable indexes for searching */
931 #define SQLITE_IndexCover     0x10        /* Disable index covering table */
932 #define SQLITE_GroupByOrder   0x20        /* Disable GROUPBY cover of ORDERBY */
933 #define SQLITE_OptMask        0xff        /* Mask of all disablable opts */
934 
935 /*
936 ** Possible values for the sqlite.magic field.
937 ** The numbers are obtained at random and have no special meaning, other
938 ** than being distinct from one another.
939 */
940 #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
941 #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
942 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
943 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
944 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
945 
946 /*
947 ** Each SQL function is defined by an instance of the following
948 ** structure.  A pointer to this structure is stored in the sqlite.aFunc
949 ** hash table.  When multiple functions have the same name, the hash table
950 ** points to a linked list of these structures.
951 */
952 struct FuncDef {
953   i16 nArg;            /* Number of arguments.  -1 means unlimited */
954   u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
955   u8 flags;            /* Some combination of SQLITE_FUNC_* */
956   void *pUserData;     /* User data parameter */
957   FuncDef *pNext;      /* Next function with same name */
958   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
959   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
960   void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
961   char *zName;         /* SQL name of the function. */
962   FuncDef *pHash;      /* Next with a different name but the same hash */
963 };
964 
965 /*
966 ** Possible values for FuncDef.flags
967 */
968 #define SQLITE_FUNC_LIKE     0x01 /* Candidate for the LIKE optimization */
969 #define SQLITE_FUNC_CASE     0x02 /* Case-sensitive LIKE-type function */
970 #define SQLITE_FUNC_EPHEM    0x04 /* Ephemeral.  Delete with VDBE */
971 #define SQLITE_FUNC_NEEDCOLL 0x08 /* sqlite3GetFuncCollSeq() might be called */
972 #define SQLITE_FUNC_PRIVATE  0x10 /* Allowed for internal use only */
973 #define SQLITE_FUNC_COUNT    0x20 /* Built-in count(*) aggregate */
974 #define SQLITE_FUNC_COALESCE 0x40 /* Built-in coalesce() or ifnull() function */
975 
976 /*
977 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
978 ** used to create the initializers for the FuncDef structures.
979 **
980 **   FUNCTION(zName, nArg, iArg, bNC, xFunc)
981 **     Used to create a scalar function definition of a function zName
982 **     implemented by C function xFunc that accepts nArg arguments. The
983 **     value passed as iArg is cast to a (void*) and made available
984 **     as the user-data (sqlite3_user_data()) for the function. If
985 **     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
986 **
987 **   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
988 **     Used to create an aggregate function definition implemented by
989 **     the C functions xStep and xFinal. The first four parameters
990 **     are interpreted in the same way as the first 4 parameters to
991 **     FUNCTION().
992 **
993 **   LIKEFUNC(zName, nArg, pArg, flags)
994 **     Used to create a scalar function definition of a function zName
995 **     that accepts nArg arguments and is implemented by a call to C
996 **     function likeFunc. Argument pArg is cast to a (void *) and made
997 **     available as the function user-data (sqlite3_user_data()). The
998 **     FuncDef.flags variable is set to the value passed as the flags
999 **     parameter.
1000 */
1001 #define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
1002   {nArg, SQLITE_UTF8, bNC*SQLITE_FUNC_NEEDCOLL, \
1003    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0}
1004 #define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
1005   {nArg, SQLITE_UTF8, bNC*SQLITE_FUNC_NEEDCOLL, \
1006    pArg, 0, xFunc, 0, 0, #zName, 0}
1007 #define LIKEFUNC(zName, nArg, arg, flags) \
1008   {nArg, SQLITE_UTF8, flags, (void *)arg, 0, likeFunc, 0, 0, #zName, 0}
1009 #define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
1010   {nArg, SQLITE_UTF8, nc*SQLITE_FUNC_NEEDCOLL, \
1011    SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0}
1012 
1013 /*
1014 ** All current savepoints are stored in a linked list starting at
1015 ** sqlite3.pSavepoint. The first element in the list is the most recently
1016 ** opened savepoint. Savepoints are added to the list by the vdbe
1017 ** OP_Savepoint instruction.
1018 */
1019 struct Savepoint {
1020   char *zName;                        /* Savepoint name (nul-terminated) */
1021   i64 nDeferredCons;                  /* Number of deferred fk violations */
1022   Savepoint *pNext;                   /* Parent savepoint (if any) */
1023 };
1024 
1025 /*
1026 ** The following are used as the second parameter to sqlite3Savepoint(),
1027 ** and as the P1 argument to the OP_Savepoint instruction.
1028 */
1029 #define SAVEPOINT_BEGIN      0
1030 #define SAVEPOINT_RELEASE    1
1031 #define SAVEPOINT_ROLLBACK   2
1032 
1033 
1034 /*
1035 ** Each SQLite module (virtual table definition) is defined by an
1036 ** instance of the following structure, stored in the sqlite3.aModule
1037 ** hash table.
1038 */
1039 struct Module {
1040   const sqlite3_module *pModule;       /* Callback pointers */
1041   const char *zName;                   /* Name passed to create_module() */
1042   void *pAux;                          /* pAux passed to create_module() */
1043   void (*xDestroy)(void *);            /* Module destructor function */
1044 };
1045 
1046 /*
1047 ** information about each column of an SQL table is held in an instance
1048 ** of this structure.
1049 */
1050 struct Column {
1051   char *zName;     /* Name of this column */
1052   Expr *pDflt;     /* Default value of this column */
1053   char *zDflt;     /* Original text of the default value */
1054   char *zType;     /* Data type for this column */
1055   char *zColl;     /* Collating sequence.  If NULL, use the default */
1056   u8 notNull;      /* True if there is a NOT NULL constraint */
1057   u8 isPrimKey;    /* True if this column is part of the PRIMARY KEY */
1058   char affinity;   /* One of the SQLITE_AFF_... values */
1059 #ifndef SQLITE_OMIT_VIRTUALTABLE
1060   u8 isHidden;     /* True if this column is 'hidden' */
1061 #endif
1062 };
1063 
1064 /*
1065 ** A "Collating Sequence" is defined by an instance of the following
1066 ** structure. Conceptually, a collating sequence consists of a name and
1067 ** a comparison routine that defines the order of that sequence.
1068 **
1069 ** There may two separate implementations of the collation function, one
1070 ** that processes text in UTF-8 encoding (CollSeq.xCmp) and another that
1071 ** processes text encoded in UTF-16 (CollSeq.xCmp16), using the machine
1072 ** native byte order. When a collation sequence is invoked, SQLite selects
1073 ** the version that will require the least expensive encoding
1074 ** translations, if any.
1075 **
1076 ** The CollSeq.pUser member variable is an extra parameter that passed in
1077 ** as the first argument to the UTF-8 comparison function, xCmp.
1078 ** CollSeq.pUser16 is the equivalent for the UTF-16 comparison function,
1079 ** xCmp16.
1080 **
1081 ** If both CollSeq.xCmp and CollSeq.xCmp16 are NULL, it means that the
1082 ** collating sequence is undefined.  Indices built on an undefined
1083 ** collating sequence may not be read or written.
1084 */
1085 struct CollSeq {
1086   char *zName;          /* Name of the collating sequence, UTF-8 encoded */
1087   u8 enc;               /* Text encoding handled by xCmp() */
1088   u8 type;              /* One of the SQLITE_COLL_... values below */
1089   void *pUser;          /* First argument to xCmp() */
1090   int (*xCmp)(void*,int, const void*, int, const void*);
1091   void (*xDel)(void*);  /* Destructor for pUser */
1092 };
1093 
1094 /*
1095 ** Allowed values of CollSeq.type:
1096 */
1097 #define SQLITE_COLL_BINARY  1  /* The default memcmp() collating sequence */
1098 #define SQLITE_COLL_NOCASE  2  /* The built-in NOCASE collating sequence */
1099 #define SQLITE_COLL_REVERSE 3  /* The built-in REVERSE collating sequence */
1100 #define SQLITE_COLL_USER    0  /* Any other user-defined collating sequence */
1101 
1102 /*
1103 ** A sort order can be either ASC or DESC.
1104 */
1105 #define SQLITE_SO_ASC       0  /* Sort in ascending order */
1106 #define SQLITE_SO_DESC      1  /* Sort in ascending order */
1107 
1108 /*
1109 ** Column affinity types.
1110 **
1111 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
1112 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
1113 ** the speed a little by numbering the values consecutively.
1114 **
1115 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
1116 ** when multiple affinity types are concatenated into a string and
1117 ** used as the P4 operand, they will be more readable.
1118 **
1119 ** Note also that the numeric types are grouped together so that testing
1120 ** for a numeric type is a single comparison.
1121 */
1122 #define SQLITE_AFF_TEXT     'a'
1123 #define SQLITE_AFF_NONE     'b'
1124 #define SQLITE_AFF_NUMERIC  'c'
1125 #define SQLITE_AFF_INTEGER  'd'
1126 #define SQLITE_AFF_REAL     'e'
1127 
1128 #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
1129 
1130 /*
1131 ** The SQLITE_AFF_MASK values masks off the significant bits of an
1132 ** affinity value.
1133 */
1134 #define SQLITE_AFF_MASK     0x67
1135 
1136 /*
1137 ** Additional bit values that can be ORed with an affinity without
1138 ** changing the affinity.
1139 */
1140 #define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
1141 #define SQLITE_STOREP2      0x10  /* Store result in reg[P2] rather than jump */
1142 #define SQLITE_NULLEQ       0x80  /* NULL=NULL */
1143 
1144 /*
1145 ** An object of this type is created for each virtual table present in
1146 ** the database schema.
1147 **
1148 ** If the database schema is shared, then there is one instance of this
1149 ** structure for each database connection (sqlite3*) that uses the shared
1150 ** schema. This is because each database connection requires its own unique
1151 ** instance of the sqlite3_vtab* handle used to access the virtual table
1152 ** implementation. sqlite3_vtab* handles can not be shared between
1153 ** database connections, even when the rest of the in-memory database
1154 ** schema is shared, as the implementation often stores the database
1155 ** connection handle passed to it via the xConnect() or xCreate() method
1156 ** during initialization internally. This database connection handle may
1157 ** then used by the virtual table implementation to access real tables
1158 ** within the database. So that they appear as part of the callers
1159 ** transaction, these accesses need to be made via the same database
1160 ** connection as that used to execute SQL operations on the virtual table.
1161 **
1162 ** All VTable objects that correspond to a single table in a shared
1163 ** database schema are initially stored in a linked-list pointed to by
1164 ** the Table.pVTable member variable of the corresponding Table object.
1165 ** When an sqlite3_prepare() operation is required to access the virtual
1166 ** table, it searches the list for the VTable that corresponds to the
1167 ** database connection doing the preparing so as to use the correct
1168 ** sqlite3_vtab* handle in the compiled query.
1169 **
1170 ** When an in-memory Table object is deleted (for example when the
1171 ** schema is being reloaded for some reason), the VTable objects are not
1172 ** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
1173 ** immediately. Instead, they are moved from the Table.pVTable list to
1174 ** another linked list headed by the sqlite3.pDisconnect member of the
1175 ** corresponding sqlite3 structure. They are then deleted/xDisconnected
1176 ** next time a statement is prepared using said sqlite3*. This is done
1177 ** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
1178 ** Refer to comments above function sqlite3VtabUnlockList() for an
1179 ** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
1180 ** list without holding the corresponding sqlite3.mutex mutex.
1181 **
1182 ** The memory for objects of this type is always allocated by
1183 ** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
1184 ** the first argument.
1185 */
1186 struct VTable {
1187   sqlite3 *db;              /* Database connection associated with this table */
1188   Module *pMod;             /* Pointer to module implementation */
1189   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
1190   int nRef;                 /* Number of pointers to this structure */
1191   VTable *pNext;            /* Next in linked list (see above) */
1192 };
1193 
1194 /*
1195 ** Each SQL table is represented in memory by an instance of the
1196 ** following structure.
1197 **
1198 ** Table.zName is the name of the table.  The case of the original
1199 ** CREATE TABLE statement is stored, but case is not significant for
1200 ** comparisons.
1201 **
1202 ** Table.nCol is the number of columns in this table.  Table.aCol is a
1203 ** pointer to an array of Column structures, one for each column.
1204 **
1205 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
1206 ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
1207 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
1208 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
1209 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
1210 ** is generated for each row of the table.  TF_HasPrimaryKey is set if
1211 ** the table has any PRIMARY KEY, INTEGER or otherwise.
1212 **
1213 ** Table.tnum is the page number for the root BTree page of the table in the
1214 ** database file.  If Table.iDb is the index of the database table backend
1215 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
1216 ** holds temporary tables and indices.  If TF_Ephemeral is set
1217 ** then the table is stored in a file that is automatically deleted
1218 ** when the VDBE cursor to the table is closed.  In this case Table.tnum
1219 ** refers VDBE cursor number that holds the table open, not to the root
1220 ** page number.  Transient tables are used to hold the results of a
1221 ** sub-query that appears instead of a real table name in the FROM clause
1222 ** of a SELECT statement.
1223 */
1224 struct Table {
1225   sqlite3 *dbMem;      /* DB connection used for lookaside allocations. */
1226   char *zName;         /* Name of the table or view */
1227   int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
1228   int nCol;            /* Number of columns in this table */
1229   Column *aCol;        /* Information about each column */
1230   Index *pIndex;       /* List of SQL indexes on this table. */
1231   int tnum;            /* Root BTree node for this table (see note above) */
1232   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
1233   u16 nRef;            /* Number of pointers to this Table */
1234   u8 tabFlags;         /* Mask of TF_* values */
1235   u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
1236   FKey *pFKey;         /* Linked list of all foreign keys in this table */
1237   char *zColAff;       /* String defining the affinity of each column */
1238 #ifndef SQLITE_OMIT_CHECK
1239   Expr *pCheck;        /* The AND of all CHECK constraints */
1240 #endif
1241 #ifndef SQLITE_OMIT_ALTERTABLE
1242   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
1243 #endif
1244 #ifndef SQLITE_OMIT_VIRTUALTABLE
1245   VTable *pVTable;     /* List of VTable objects. */
1246   int nModuleArg;      /* Number of arguments to the module */
1247   char **azModuleArg;  /* Text of all module args. [0] is module name */
1248 #endif
1249   Trigger *pTrigger;   /* List of triggers stored in pSchema */
1250   Schema *pSchema;     /* Schema that contains this table */
1251   Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
1252 };
1253 
1254 /*
1255 ** Allowed values for Tabe.tabFlags.
1256 */
1257 #define TF_Readonly        0x01    /* Read-only system table */
1258 #define TF_Ephemeral       0x02    /* An ephemeral table */
1259 #define TF_HasPrimaryKey   0x04    /* Table has a primary key */
1260 #define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
1261 #define TF_Virtual         0x10    /* Is a virtual table */
1262 #define TF_NeedMetadata    0x20    /* aCol[].zType and aCol[].pColl missing */
1263 
1264 
1265 
1266 /*
1267 ** Test to see whether or not a table is a virtual table.  This is
1268 ** done as a macro so that it will be optimized out when virtual
1269 ** table support is omitted from the build.
1270 */
1271 #ifndef SQLITE_OMIT_VIRTUALTABLE
1272 #  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
1273 #  define IsHiddenColumn(X) ((X)->isHidden)
1274 #else
1275 #  define IsVirtual(X)      0
1276 #  define IsHiddenColumn(X) 0
1277 #endif
1278 
1279 /*
1280 ** Each foreign key constraint is an instance of the following structure.
1281 **
1282 ** A foreign key is associated with two tables.  The "from" table is
1283 ** the table that contains the REFERENCES clause that creates the foreign
1284 ** key.  The "to" table is the table that is named in the REFERENCES clause.
1285 ** Consider this example:
1286 **
1287 **     CREATE TABLE ex1(
1288 **       a INTEGER PRIMARY KEY,
1289 **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
1290 **     );
1291 **
1292 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
1293 **
1294 ** Each REFERENCES clause generates an instance of the following structure
1295 ** which is attached to the from-table.  The to-table need not exist when
1296 ** the from-table is created.  The existence of the to-table is not checked.
1297 */
1298 struct FKey {
1299   Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
1300   FKey *pNextFrom;  /* Next foreign key in pFrom */
1301   char *zTo;        /* Name of table that the key points to (aka: Parent) */
1302   FKey *pNextTo;    /* Next foreign key on table named zTo */
1303   FKey *pPrevTo;    /* Previous foreign key on table named zTo */
1304   int nCol;         /* Number of columns in this key */
1305   /* EV: R-30323-21917 */
1306   u8 isDeferred;    /* True if constraint checking is deferred till COMMIT */
1307   u8 aAction[2];          /* ON DELETE and ON UPDATE actions, respectively */
1308   Trigger *apTrigger[2];  /* Triggers for aAction[] actions */
1309   struct sColMap {  /* Mapping of columns in pFrom to columns in zTo */
1310     int iFrom;         /* Index of column in pFrom */
1311     char *zCol;        /* Name of column in zTo.  If 0 use PRIMARY KEY */
1312   } aCol[1];        /* One entry for each of nCol column s */
1313 };
1314 
1315 /*
1316 ** SQLite supports many different ways to resolve a constraint
1317 ** error.  ROLLBACK processing means that a constraint violation
1318 ** causes the operation in process to fail and for the current transaction
1319 ** to be rolled back.  ABORT processing means the operation in process
1320 ** fails and any prior changes from that one operation are backed out,
1321 ** but the transaction is not rolled back.  FAIL processing means that
1322 ** the operation in progress stops and returns an error code.  But prior
1323 ** changes due to the same operation are not backed out and no rollback
1324 ** occurs.  IGNORE means that the particular row that caused the constraint
1325 ** error is not inserted or updated.  Processing continues and no error
1326 ** is returned.  REPLACE means that preexisting database rows that caused
1327 ** a UNIQUE constraint violation are removed so that the new insert or
1328 ** update can proceed.  Processing continues and no error is reported.
1329 **
1330 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
1331 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
1332 ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
1333 ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
1334 ** referenced table row is propagated into the row that holds the
1335 ** foreign key.
1336 **
1337 ** The following symbolic values are used to record which type
1338 ** of action to take.
1339 */
1340 #define OE_None     0   /* There is no constraint to check */
1341 #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
1342 #define OE_Abort    2   /* Back out changes but do no rollback transaction */
1343 #define OE_Fail     3   /* Stop the operation but leave all prior changes */
1344 #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
1345 #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
1346 
1347 #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
1348 #define OE_SetNull  7   /* Set the foreign key value to NULL */
1349 #define OE_SetDflt  8   /* Set the foreign key value to its default */
1350 #define OE_Cascade  9   /* Cascade the changes */
1351 
1352 #define OE_Default  99  /* Do whatever the default action is */
1353 
1354 
1355 /*
1356 ** An instance of the following structure is passed as the first
1357 ** argument to sqlite3VdbeKeyCompare and is used to control the
1358 ** comparison of the two index keys.
1359 */
1360 struct KeyInfo {
1361   sqlite3 *db;        /* The database connection */
1362   u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
1363   u16 nField;         /* Number of entries in aColl[] */
1364   u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
1365   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
1366 };
1367 
1368 /*
1369 ** An instance of the following structure holds information about a
1370 ** single index record that has already been parsed out into individual
1371 ** values.
1372 **
1373 ** A record is an object that contains one or more fields of data.
1374 ** Records are used to store the content of a table row and to store
1375 ** the key of an index.  A blob encoding of a record is created by
1376 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
1377 ** OP_Column opcode.
1378 **
1379 ** This structure holds a record that has already been disassembled
1380 ** into its constituent fields.
1381 */
1382 struct UnpackedRecord {
1383   KeyInfo *pKeyInfo;  /* Collation and sort-order information */
1384   u16 nField;         /* Number of entries in apMem[] */
1385   u16 flags;          /* Boolean settings.  UNPACKED_... below */
1386   i64 rowid;          /* Used by UNPACKED_PREFIX_SEARCH */
1387   Mem *aMem;          /* Values */
1388 };
1389 
1390 /*
1391 ** Allowed values of UnpackedRecord.flags
1392 */
1393 #define UNPACKED_NEED_FREE     0x0001  /* Memory is from sqlite3Malloc() */
1394 #define UNPACKED_NEED_DESTROY  0x0002  /* apMem[]s should all be destroyed */
1395 #define UNPACKED_IGNORE_ROWID  0x0004  /* Ignore trailing rowid on key1 */
1396 #define UNPACKED_INCRKEY       0x0008  /* Make this key an epsilon larger */
1397 #define UNPACKED_PREFIX_MATCH  0x0010  /* A prefix match is considered OK */
1398 #define UNPACKED_PREFIX_SEARCH 0x0020  /* A prefix match is considered OK */
1399 
1400 /*
1401 ** Each SQL index is represented in memory by an
1402 ** instance of the following structure.
1403 **
1404 ** The columns of the table that are to be indexed are described
1405 ** by the aiColumn[] field of this structure.  For example, suppose
1406 ** we have the following table and index:
1407 **
1408 **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
1409 **     CREATE INDEX Ex2 ON Ex1(c3,c1);
1410 **
1411 ** In the Table structure describing Ex1, nCol==3 because there are
1412 ** three columns in the table.  In the Index structure describing
1413 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
1414 ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
1415 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
1416 ** The second column to be indexed (c1) has an index of 0 in
1417 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
1418 **
1419 ** The Index.onError field determines whether or not the indexed columns
1420 ** must be unique and what to do if they are not.  When Index.onError=OE_None,
1421 ** it means this is not a unique index.  Otherwise it is a unique index
1422 ** and the value of Index.onError indicate the which conflict resolution
1423 ** algorithm to employ whenever an attempt is made to insert a non-unique
1424 ** element.
1425 */
1426 struct Index {
1427   char *zName;     /* Name of this index */
1428   int nColumn;     /* Number of columns in the table used by this index */
1429   int *aiColumn;   /* Which columns are used by this index.  1st is 0 */
1430   unsigned *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
1431   Table *pTable;   /* The SQL table being indexed */
1432   int tnum;        /* Page containing root of this index in database file */
1433   u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
1434   u8 autoIndex;    /* True if is automatically created (ex: by UNIQUE) */
1435   char *zColAff;   /* String defining the affinity of each column */
1436   Index *pNext;    /* The next index associated with the same table */
1437   Schema *pSchema; /* Schema containing this index */
1438   u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
1439   char **azColl;   /* Array of collation sequence names for index */
1440   IndexSample *aSample;    /* Array of SQLITE_INDEX_SAMPLES samples */
1441 };
1442 
1443 /*
1444 ** Each sample stored in the sqlite_stat2 table is represented in memory
1445 ** using a structure of this type.
1446 */
1447 struct IndexSample {
1448   union {
1449     char *z;        /* Value if eType is SQLITE_TEXT or SQLITE_BLOB */
1450     double r;       /* Value if eType is SQLITE_FLOAT or SQLITE_INTEGER */
1451   } u;
1452   u8 eType;         /* SQLITE_NULL, SQLITE_INTEGER ... etc. */
1453   u8 nByte;         /* Size in byte of text or blob. */
1454 };
1455 
1456 /*
1457 ** Each token coming out of the lexer is an instance of
1458 ** this structure.  Tokens are also used as part of an expression.
1459 **
1460 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
1461 ** may contain random values.  Do not make any assumptions about Token.dyn
1462 ** and Token.n when Token.z==0.
1463 */
1464 struct Token {
1465   const char *z;     /* Text of the token.  Not NULL-terminated! */
1466   unsigned int n;    /* Number of characters in this token */
1467 };
1468 
1469 /*
1470 ** An instance of this structure contains information needed to generate
1471 ** code for a SELECT that contains aggregate functions.
1472 **
1473 ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
1474 ** pointer to this structure.  The Expr.iColumn field is the index in
1475 ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
1476 ** code for that node.
1477 **
1478 ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
1479 ** original Select structure that describes the SELECT statement.  These
1480 ** fields do not need to be freed when deallocating the AggInfo structure.
1481 */
1482 struct AggInfo {
1483   u8 directMode;          /* Direct rendering mode means take data directly
1484                           ** from source tables rather than from accumulators */
1485   u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
1486                           ** than the source table */
1487   int sortingIdx;         /* Cursor number of the sorting index */
1488   ExprList *pGroupBy;     /* The group by clause */
1489   int nSortingColumn;     /* Number of columns in the sorting index */
1490   struct AggInfo_col {    /* For each column used in source tables */
1491     Table *pTab;             /* Source table */
1492     int iTable;              /* Cursor number of the source table */
1493     int iColumn;             /* Column number within the source table */
1494     int iSorterColumn;       /* Column number in the sorting index */
1495     int iMem;                /* Memory location that acts as accumulator */
1496     Expr *pExpr;             /* The original expression */
1497   } *aCol;
1498   int nColumn;            /* Number of used entries in aCol[] */
1499   int nColumnAlloc;       /* Number of slots allocated for aCol[] */
1500   int nAccumulator;       /* Number of columns that show through to the output.
1501                           ** Additional columns are used only as parameters to
1502                           ** aggregate functions */
1503   struct AggInfo_func {   /* For each aggregate function */
1504     Expr *pExpr;             /* Expression encoding the function */
1505     FuncDef *pFunc;          /* The aggregate function implementation */
1506     int iMem;                /* Memory location that acts as accumulator */
1507     int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
1508   } *aFunc;
1509   int nFunc;              /* Number of entries in aFunc[] */
1510   int nFuncAlloc;         /* Number of slots allocated for aFunc[] */
1511 };
1512 
1513 /*
1514 ** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
1515 ** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
1516 ** than 32767 we have to make it 32-bit.  16-bit is preferred because
1517 ** it uses less memory in the Expr object, which is a big memory user
1518 ** in systems with lots of prepared statements.  And few applications
1519 ** need more than about 10 or 20 variables.  But some extreme users want
1520 ** to have prepared statements with over 32767 variables, and for them
1521 ** the option is available (at compile-time).
1522 */
1523 #if SQLITE_MAX_VARIABLE_NUMBER<=32767
1524 typedef i16 ynVar;
1525 #else
1526 typedef int ynVar;
1527 #endif
1528 
1529 /*
1530 ** Each node of an expression in the parse tree is an instance
1531 ** of this structure.
1532 **
1533 ** Expr.op is the opcode. The integer parser token codes are reused
1534 ** as opcodes here. For example, the parser defines TK_GE to be an integer
1535 ** code representing the ">=" operator. This same integer code is reused
1536 ** to represent the greater-than-or-equal-to operator in the expression
1537 ** tree.
1538 **
1539 ** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
1540 ** or TK_STRING), then Expr.token contains the text of the SQL literal. If
1541 ** the expression is a variable (TK_VARIABLE), then Expr.token contains the
1542 ** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
1543 ** then Expr.token contains the name of the function.
1544 **
1545 ** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
1546 ** binary operator. Either or both may be NULL.
1547 **
1548 ** Expr.x.pList is a list of arguments if the expression is an SQL function,
1549 ** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
1550 ** Expr.x.pSelect is used if the expression is a sub-select or an expression of
1551 ** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
1552 ** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
1553 ** valid.
1554 **
1555 ** An expression of the form ID or ID.ID refers to a column in a table.
1556 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
1557 ** the integer cursor number of a VDBE cursor pointing to that table and
1558 ** Expr.iColumn is the column number for the specific column.  If the
1559 ** expression is used as a result in an aggregate SELECT, then the
1560 ** value is also stored in the Expr.iAgg column in the aggregate so that
1561 ** it can be accessed after all aggregates are computed.
1562 **
1563 ** If the expression is an unbound variable marker (a question mark
1564 ** character '?' in the original SQL) then the Expr.iTable holds the index
1565 ** number for that variable.
1566 **
1567 ** If the expression is a subquery then Expr.iColumn holds an integer
1568 ** register number containing the result of the subquery.  If the
1569 ** subquery gives a constant result, then iTable is -1.  If the subquery
1570 ** gives a different answer at different times during statement processing
1571 ** then iTable is the address of a subroutine that computes the subquery.
1572 **
1573 ** If the Expr is of type OP_Column, and the table it is selecting from
1574 ** is a disk table or the "old.*" pseudo-table, then pTab points to the
1575 ** corresponding table definition.
1576 **
1577 ** ALLOCATION NOTES:
1578 **
1579 ** Expr objects can use a lot of memory space in database schema.  To
1580 ** help reduce memory requirements, sometimes an Expr object will be
1581 ** truncated.  And to reduce the number of memory allocations, sometimes
1582 ** two or more Expr objects will be stored in a single memory allocation,
1583 ** together with Expr.zToken strings.
1584 **
1585 ** If the EP_Reduced and EP_TokenOnly flags are set when
1586 ** an Expr object is truncated.  When EP_Reduced is set, then all
1587 ** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
1588 ** are contained within the same memory allocation.  Note, however, that
1589 ** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
1590 ** allocated, regardless of whether or not EP_Reduced is set.
1591 */
1592 struct Expr {
1593   u8 op;                 /* Operation performed by this node */
1594   char affinity;         /* The affinity of the column or 0 if not a column */
1595   u16 flags;             /* Various flags.  EP_* See below */
1596   union {
1597     char *zToken;          /* Token value. Zero terminated and dequoted */
1598     int iValue;            /* Integer value if EP_IntValue */
1599   } u;
1600 
1601   /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
1602   ** space is allocated for the fields below this point. An attempt to
1603   ** access them will result in a segfault or malfunction.
1604   *********************************************************************/
1605 
1606   Expr *pLeft;           /* Left subnode */
1607   Expr *pRight;          /* Right subnode */
1608   union {
1609     ExprList *pList;     /* Function arguments or in "<expr> IN (<expr-list)" */
1610     Select *pSelect;     /* Used for sub-selects and "<expr> IN (<select>)" */
1611   } x;
1612   CollSeq *pColl;        /* The collation type of the column or 0 */
1613 
1614   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
1615   ** space is allocated for the fields below this point. An attempt to
1616   ** access them will result in a segfault or malfunction.
1617   *********************************************************************/
1618 
1619   int iTable;            /* TK_COLUMN: cursor number of table holding column
1620                          ** TK_REGISTER: register number
1621                          ** TK_TRIGGER: 1 -> new, 0 -> old */
1622   ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
1623                          ** TK_VARIABLE: variable number (always >= 1). */
1624   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
1625   i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
1626   u8 flags2;             /* Second set of flags.  EP2_... */
1627   u8 op2;                /* If a TK_REGISTER, the original value of Expr.op */
1628   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
1629   Table *pTab;           /* Table for TK_COLUMN expressions. */
1630 #if SQLITE_MAX_EXPR_DEPTH>0
1631   int nHeight;           /* Height of the tree headed by this node */
1632 #endif
1633 };
1634 
1635 /*
1636 ** The following are the meanings of bits in the Expr.flags field.
1637 */
1638 #define EP_FromJoin   0x0001  /* Originated in ON or USING clause of a join */
1639 #define EP_Agg        0x0002  /* Contains one or more aggregate functions */
1640 #define EP_Resolved   0x0004  /* IDs have been resolved to COLUMNs */
1641 #define EP_Error      0x0008  /* Expression contains one or more errors */
1642 #define EP_Distinct   0x0010  /* Aggregate function with DISTINCT keyword */
1643 #define EP_VarSelect  0x0020  /* pSelect is correlated, not constant */
1644 #define EP_DblQuoted  0x0040  /* token.z was originally in "..." */
1645 #define EP_InfixFunc  0x0080  /* True for an infix function: LIKE, GLOB, etc */
1646 #define EP_ExpCollate 0x0100  /* Collating sequence specified explicitly */
1647 #define EP_FixedDest  0x0200  /* Result needed in a specific register */
1648 #define EP_IntValue   0x0400  /* Integer value contained in u.iValue */
1649 #define EP_xIsSelect  0x0800  /* x.pSelect is valid (otherwise x.pList is) */
1650 
1651 #define EP_Reduced    0x1000  /* Expr struct is EXPR_REDUCEDSIZE bytes only */
1652 #define EP_TokenOnly  0x2000  /* Expr struct is EXPR_TOKENONLYSIZE bytes only */
1653 #define EP_Static     0x4000  /* Held in memory not obtained from malloc() */
1654 
1655 /*
1656 ** The following are the meanings of bits in the Expr.flags2 field.
1657 */
1658 #define EP2_MallocedToken  0x0001  /* Need to sqlite3DbFree() Expr.zToken */
1659 #define EP2_Irreducible    0x0002  /* Cannot EXPRDUP_REDUCE this Expr */
1660 
1661 /*
1662 ** The pseudo-routine sqlite3ExprSetIrreducible sets the EP2_Irreducible
1663 ** flag on an expression structure.  This flag is used for VV&A only.  The
1664 ** routine is implemented as a macro that only works when in debugging mode,
1665 ** so as not to burden production code.
1666 */
1667 #ifdef SQLITE_DEBUG
1668 # define ExprSetIrreducible(X)  (X)->flags2 |= EP2_Irreducible
1669 #else
1670 # define ExprSetIrreducible(X)
1671 #endif
1672 
1673 /*
1674 ** These macros can be used to test, set, or clear bits in the
1675 ** Expr.flags field.
1676 */
1677 #define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
1678 #define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
1679 #define ExprSetProperty(E,P)     (E)->flags|=(P)
1680 #define ExprClearProperty(E,P)   (E)->flags&=~(P)
1681 
1682 /*
1683 ** Macros to determine the number of bytes required by a normal Expr
1684 ** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
1685 ** and an Expr struct with the EP_TokenOnly flag set.
1686 */
1687 #define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
1688 #define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
1689 #define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */
1690 
1691 /*
1692 ** Flags passed to the sqlite3ExprDup() function. See the header comment
1693 ** above sqlite3ExprDup() for details.
1694 */
1695 #define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */
1696 
1697 /*
1698 ** A list of expressions.  Each expression may optionally have a
1699 ** name.  An expr/name combination can be used in several ways, such
1700 ** as the list of "expr AS ID" fields following a "SELECT" or in the
1701 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
1702 ** also be used as the argument to a function, in which case the a.zName
1703 ** field is not used.
1704 */
1705 struct ExprList {
1706   int nExpr;             /* Number of expressions on the list */
1707   int nAlloc;            /* Number of entries allocated below */
1708   int iECursor;          /* VDBE Cursor associated with this ExprList */
1709   struct ExprList_item {
1710     Expr *pExpr;           /* The list of expressions */
1711     char *zName;           /* Token associated with this expression */
1712     char *zSpan;           /* Original text of the expression */
1713     u8 sortOrder;          /* 1 for DESC or 0 for ASC */
1714     u8 done;               /* A flag to indicate when processing is finished */
1715     u16 iCol;              /* For ORDER BY, column number in result set */
1716     u16 iAlias;            /* Index into Parse.aAlias[] for zName */
1717   } *a;                  /* One entry for each expression */
1718 };
1719 
1720 /*
1721 ** An instance of this structure is used by the parser to record both
1722 ** the parse tree for an expression and the span of input text for an
1723 ** expression.
1724 */
1725 struct ExprSpan {
1726   Expr *pExpr;          /* The expression parse tree */
1727   const char *zStart;   /* First character of input text */
1728   const char *zEnd;     /* One character past the end of input text */
1729 };
1730 
1731 /*
1732 ** An instance of this structure can hold a simple list of identifiers,
1733 ** such as the list "a,b,c" in the following statements:
1734 **
1735 **      INSERT INTO t(a,b,c) VALUES ...;
1736 **      CREATE INDEX idx ON t(a,b,c);
1737 **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
1738 **
1739 ** The IdList.a.idx field is used when the IdList represents the list of
1740 ** column names after a table name in an INSERT statement.  In the statement
1741 **
1742 **     INSERT INTO t(a,b,c) ...
1743 **
1744 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
1745 */
1746 struct IdList {
1747   struct IdList_item {
1748     char *zName;      /* Name of the identifier */
1749     int idx;          /* Index in some Table.aCol[] of a column named zName */
1750   } *a;
1751   int nId;         /* Number of identifiers on the list */
1752   int nAlloc;      /* Number of entries allocated for a[] below */
1753 };
1754 
1755 /*
1756 ** The bitmask datatype defined below is used for various optimizations.
1757 **
1758 ** Changing this from a 64-bit to a 32-bit type limits the number of
1759 ** tables in a join to 32 instead of 64.  But it also reduces the size
1760 ** of the library by 738 bytes on ix86.
1761 */
1762 typedef u64 Bitmask;
1763 
1764 /*
1765 ** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
1766 */
1767 #define BMS  ((int)(sizeof(Bitmask)*8))
1768 
1769 /*
1770 ** The following structure describes the FROM clause of a SELECT statement.
1771 ** Each table or subquery in the FROM clause is a separate element of
1772 ** the SrcList.a[] array.
1773 **
1774 ** With the addition of multiple database support, the following structure
1775 ** can also be used to describe a particular table such as the table that
1776 ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
1777 ** such a table must be a simple name: ID.  But in SQLite, the table can
1778 ** now be identified by a database name, a dot, then the table name: ID.ID.
1779 **
1780 ** The jointype starts out showing the join type between the current table
1781 ** and the next table on the list.  The parser builds the list this way.
1782 ** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
1783 ** jointype expresses the join between the table and the previous table.
1784 **
1785 ** In the colUsed field, the high-order bit (bit 63) is set if the table
1786 ** contains more than 63 columns and the 64-th or later column is used.
1787 */
1788 struct SrcList {
1789   i16 nSrc;        /* Number of tables or subqueries in the FROM clause */
1790   i16 nAlloc;      /* Number of entries allocated in a[] below */
1791   struct SrcList_item {
1792     char *zDatabase;  /* Name of database holding this table */
1793     char *zName;      /* Name of the table */
1794     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
1795     Table *pTab;      /* An SQL table corresponding to zName */
1796     Select *pSelect;  /* A SELECT statement used in place of a table name */
1797     u8 isPopulated;   /* Temporary table associated with SELECT is populated */
1798     u8 jointype;      /* Type of join between this able and the previous */
1799     u8 notIndexed;    /* True if there is a NOT INDEXED clause */
1800     int iCursor;      /* The VDBE cursor number used to access this table */
1801     Expr *pOn;        /* The ON clause of a join */
1802     IdList *pUsing;   /* The USING clause of a join */
1803     Bitmask colUsed;  /* Bit N (1<<N) set if column N of pTab is used */
1804     char *zIndex;     /* Identifier from "INDEXED BY <zIndex>" clause */
1805     Index *pIndex;    /* Index structure corresponding to zIndex, if any */
1806   } a[1];             /* One entry for each identifier on the list */
1807 };
1808 
1809 /*
1810 ** Permitted values of the SrcList.a.jointype field
1811 */
1812 #define JT_INNER     0x0001    /* Any kind of inner or cross join */
1813 #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
1814 #define JT_NATURAL   0x0004    /* True for a "natural" join */
1815 #define JT_LEFT      0x0008    /* Left outer join */
1816 #define JT_RIGHT     0x0010    /* Right outer join */
1817 #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
1818 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
1819 
1820 
1821 /*
1822 ** A WherePlan object holds information that describes a lookup
1823 ** strategy.
1824 **
1825 ** This object is intended to be opaque outside of the where.c module.
1826 ** It is included here only so that that compiler will know how big it
1827 ** is.  None of the fields in this object should be used outside of
1828 ** the where.c module.
1829 **
1830 ** Within the union, pIdx is only used when wsFlags&WHERE_INDEXED is true.
1831 ** pTerm is only used when wsFlags&WHERE_MULTI_OR is true.  And pVtabIdx
1832 ** is only used when wsFlags&WHERE_VIRTUALTABLE is true.  It is never the
1833 ** case that more than one of these conditions is true.
1834 */
1835 struct WherePlan {
1836   u32 wsFlags;                   /* WHERE_* flags that describe the strategy */
1837   u32 nEq;                       /* Number of == constraints */
1838   union {
1839     Index *pIdx;                   /* Index when WHERE_INDEXED is true */
1840     struct WhereTerm *pTerm;       /* WHERE clause term for OR-search */
1841     sqlite3_index_info *pVtabIdx;  /* Virtual table index to use */
1842   } u;
1843 };
1844 
1845 /*
1846 ** For each nested loop in a WHERE clause implementation, the WhereInfo
1847 ** structure contains a single instance of this structure.  This structure
1848 ** is intended to be private the the where.c module and should not be
1849 ** access or modified by other modules.
1850 **
1851 ** The pIdxInfo field is used to help pick the best index on a
1852 ** virtual table.  The pIdxInfo pointer contains indexing
1853 ** information for the i-th table in the FROM clause before reordering.
1854 ** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
1855 ** All other information in the i-th WhereLevel object for the i-th table
1856 ** after FROM clause ordering.
1857 */
1858 struct WhereLevel {
1859   WherePlan plan;       /* query plan for this element of the FROM clause */
1860   int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
1861   int iTabCur;          /* The VDBE cursor used to access the table */
1862   int iIdxCur;          /* The VDBE cursor used to access pIdx */
1863   int addrBrk;          /* Jump here to break out of the loop */
1864   int addrNxt;          /* Jump here to start the next IN combination */
1865   int addrCont;         /* Jump here to continue with the next loop cycle */
1866   int addrFirst;        /* First instruction of interior of the loop */
1867   u8 iFrom;             /* Which entry in the FROM clause */
1868   u8 op, p5;            /* Opcode and P5 of the opcode that ends the loop */
1869   int p1, p2;           /* Operands of the opcode used to ends the loop */
1870   union {               /* Information that depends on plan.wsFlags */
1871     struct {
1872       int nIn;              /* Number of entries in aInLoop[] */
1873       struct InLoop {
1874         int iCur;              /* The VDBE cursor used by this IN operator */
1875         int addrInTop;         /* Top of the IN loop */
1876       } *aInLoop;           /* Information about each nested IN operator */
1877     } in;                 /* Used when plan.wsFlags&WHERE_IN_ABLE */
1878   } u;
1879 
1880   /* The following field is really not part of the current level.  But
1881   ** we need a place to cache virtual table index information for each
1882   ** virtual table in the FROM clause and the WhereLevel structure is
1883   ** a convenient place since there is one WhereLevel for each FROM clause
1884   ** element.
1885   */
1886   sqlite3_index_info *pIdxInfo;  /* Index info for n-th source table */
1887 };
1888 
1889 /*
1890 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
1891 ** and the WhereInfo.wctrlFlags member.
1892 */
1893 #define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
1894 #define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
1895 #define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
1896 #define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
1897 #define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
1898 #define WHERE_OMIT_OPEN        0x0010 /* Table cursors are already open */
1899 #define WHERE_OMIT_CLOSE       0x0020 /* Omit close of table & index cursors */
1900 #define WHERE_FORCE_TABLE      0x0040 /* Do not use an index-only search */
1901 #define WHERE_ONETABLE_ONLY    0x0080 /* Only code the 1st table in pTabList */
1902 
1903 /*
1904 ** The WHERE clause processing routine has two halves.  The
1905 ** first part does the start of the WHERE loop and the second
1906 ** half does the tail of the WHERE loop.  An instance of
1907 ** this structure is returned by the first half and passed
1908 ** into the second half to give some continuity.
1909 */
1910 struct WhereInfo {
1911   Parse *pParse;       /* Parsing and code generating context */
1912   u16 wctrlFlags;      /* Flags originally passed to sqlite3WhereBegin() */
1913   u8 okOnePass;        /* Ok to use one-pass algorithm for UPDATE or DELETE */
1914   u8 untestedTerms;    /* Not all WHERE terms resolved by outer loop */
1915   SrcList *pTabList;             /* List of tables in the join */
1916   int iTop;                      /* The very beginning of the WHERE loop */
1917   int iContinue;                 /* Jump here to continue with next record */
1918   int iBreak;                    /* Jump here to break out of the loop */
1919   int nLevel;                    /* Number of nested loop */
1920   struct WhereClause *pWC;       /* Decomposition of the WHERE clause */
1921   double savedNQueryLoop;        /* pParse->nQueryLoop outside the WHERE loop */
1922   WhereLevel a[1];               /* Information about each nest loop in WHERE */
1923 };
1924 
1925 /*
1926 ** A NameContext defines a context in which to resolve table and column
1927 ** names.  The context consists of a list of tables (the pSrcList) field and
1928 ** a list of named expression (pEList).  The named expression list may
1929 ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
1930 ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
1931 ** pEList corresponds to the result set of a SELECT and is NULL for
1932 ** other statements.
1933 **
1934 ** NameContexts can be nested.  When resolving names, the inner-most
1935 ** context is searched first.  If no match is found, the next outer
1936 ** context is checked.  If there is still no match, the next context
1937 ** is checked.  This process continues until either a match is found
1938 ** or all contexts are check.  When a match is found, the nRef member of
1939 ** the context containing the match is incremented.
1940 **
1941 ** Each subquery gets a new NameContext.  The pNext field points to the
1942 ** NameContext in the parent query.  Thus the process of scanning the
1943 ** NameContext list corresponds to searching through successively outer
1944 ** subqueries looking for a match.
1945 */
1946 struct NameContext {
1947   Parse *pParse;       /* The parser */
1948   SrcList *pSrcList;   /* One or more tables used to resolve names */
1949   ExprList *pEList;    /* Optional list of named expressions */
1950   int nRef;            /* Number of names resolved by this context */
1951   int nErr;            /* Number of errors encountered while resolving names */
1952   u8 allowAgg;         /* Aggregate functions allowed here */
1953   u8 hasAgg;           /* True if aggregates are seen */
1954   u8 isCheck;          /* True if resolving names in a CHECK constraint */
1955   int nDepth;          /* Depth of subquery recursion. 1 for no recursion */
1956   AggInfo *pAggInfo;   /* Information about aggregates at this level */
1957   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
1958 };
1959 
1960 /*
1961 ** An instance of the following structure contains all information
1962 ** needed to generate code for a single SELECT statement.
1963 **
1964 ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
1965 ** If there is a LIMIT clause, the parser sets nLimit to the value of the
1966 ** limit and nOffset to the value of the offset (or 0 if there is not
1967 ** offset).  But later on, nLimit and nOffset become the memory locations
1968 ** in the VDBE that record the limit and offset counters.
1969 **
1970 ** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
1971 ** These addresses must be stored so that we can go back and fill in
1972 ** the P4_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
1973 ** the number of columns in P2 can be computed at the same time
1974 ** as the OP_OpenEphm instruction is coded because not
1975 ** enough information about the compound query is known at that point.
1976 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
1977 ** for the result set.  The KeyInfo for addrOpenTran[2] contains collating
1978 ** sequences for the ORDER BY clause.
1979 */
1980 struct Select {
1981   ExprList *pEList;      /* The fields of the result */
1982   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
1983   char affinity;         /* MakeRecord with this affinity for SRT_Set */
1984   u16 selFlags;          /* Various SF_* values */
1985   SrcList *pSrc;         /* The FROM clause */
1986   Expr *pWhere;          /* The WHERE clause */
1987   ExprList *pGroupBy;    /* The GROUP BY clause */
1988   Expr *pHaving;         /* The HAVING clause */
1989   ExprList *pOrderBy;    /* The ORDER BY clause */
1990   Select *pPrior;        /* Prior select in a compound select statement */
1991   Select *pNext;         /* Next select to the left in a compound */
1992   Select *pRightmost;    /* Right-most select in a compound select statement */
1993   Expr *pLimit;          /* LIMIT expression. NULL means not used. */
1994   Expr *pOffset;         /* OFFSET expression. NULL means not used. */
1995   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
1996   int addrOpenEphm[3];   /* OP_OpenEphem opcodes related to this select */
1997 };
1998 
1999 /*
2000 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
2001 ** "Select Flag".
2002 */
2003 #define SF_Distinct        0x0001  /* Output should be DISTINCT */
2004 #define SF_Resolved        0x0002  /* Identifiers have been resolved */
2005 #define SF_Aggregate       0x0004  /* Contains aggregate functions */
2006 #define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
2007 #define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
2008 #define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
2009 
2010 
2011 /*
2012 ** The results of a select can be distributed in several ways.  The
2013 ** "SRT" prefix means "SELECT Result Type".
2014 */
2015 #define SRT_Union        1  /* Store result as keys in an index */
2016 #define SRT_Except       2  /* Remove result from a UNION index */
2017 #define SRT_Exists       3  /* Store 1 if the result is not empty */
2018 #define SRT_Discard      4  /* Do not save the results anywhere */
2019 
2020 /* The ORDER BY clause is ignored for all of the above */
2021 #define IgnorableOrderby(X) ((X->eDest)<=SRT_Discard)
2022 
2023 #define SRT_Output       5  /* Output each row of result */
2024 #define SRT_Mem          6  /* Store result in a memory cell */
2025 #define SRT_Set          7  /* Store results as keys in an index */
2026 #define SRT_Table        8  /* Store result as data with an automatic rowid */
2027 #define SRT_EphemTab     9  /* Create transient tab and store like SRT_Table */
2028 #define SRT_Coroutine   10  /* Generate a single row of result */
2029 
2030 /*
2031 ** A structure used to customize the behavior of sqlite3Select(). See
2032 ** comments above sqlite3Select() for details.
2033 */
2034 typedef struct SelectDest SelectDest;
2035 struct SelectDest {
2036   u8 eDest;         /* How to dispose of the results */
2037   u8 affinity;      /* Affinity used when eDest==SRT_Set */
2038   int iParm;        /* A parameter used by the eDest disposal method */
2039   int iMem;         /* Base register where results are written */
2040   int nMem;         /* Number of registers allocated */
2041 };
2042 
2043 /*
2044 ** During code generation of statements that do inserts into AUTOINCREMENT
2045 ** tables, the following information is attached to the Table.u.autoInc.p
2046 ** pointer of each autoincrement table to record some side information that
2047 ** the code generator needs.  We have to keep per-table autoincrement
2048 ** information in case inserts are down within triggers.  Triggers do not
2049 ** normally coordinate their activities, but we do need to coordinate the
2050 ** loading and saving of autoincrement information.
2051 */
2052 struct AutoincInfo {
2053   AutoincInfo *pNext;   /* Next info block in a list of them all */
2054   Table *pTab;          /* Table this info block refers to */
2055   int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
2056   int regCtr;           /* Memory register holding the rowid counter */
2057 };
2058 
2059 /*
2060 ** Size of the column cache
2061 */
2062 #ifndef SQLITE_N_COLCACHE
2063 # define SQLITE_N_COLCACHE 10
2064 #endif
2065 
2066 /*
2067 ** At least one instance of the following structure is created for each
2068 ** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
2069 ** statement. All such objects are stored in the linked list headed at
2070 ** Parse.pTriggerPrg and deleted once statement compilation has been
2071 ** completed.
2072 **
2073 ** A Vdbe sub-program that implements the body and WHEN clause of trigger
2074 ** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
2075 ** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
2076 ** The Parse.pTriggerPrg list never contains two entries with the same
2077 ** values for both pTrigger and orconf.
2078 **
2079 ** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
2080 ** accessed (or set to 0 for triggers fired as a result of INSERT
2081 ** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
2082 ** a mask of new.* columns used by the program.
2083 */
2084 struct TriggerPrg {
2085   Trigger *pTrigger;      /* Trigger this program was coded from */
2086   int orconf;             /* Default ON CONFLICT policy */
2087   SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
2088   u32 aColmask[2];        /* Masks of old.*, new.* columns accessed */
2089   TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
2090 };
2091 
2092 /*
2093 ** An SQL parser context.  A copy of this structure is passed through
2094 ** the parser and down into all the parser action routine in order to
2095 ** carry around information that is global to the entire parse.
2096 **
2097 ** The structure is divided into two parts.  When the parser and code
2098 ** generate call themselves recursively, the first part of the structure
2099 ** is constant but the second part is reset at the beginning and end of
2100 ** each recursion.
2101 **
2102 ** The nTableLock and aTableLock variables are only used if the shared-cache
2103 ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
2104 ** used to store the set of table-locks required by the statement being
2105 ** compiled. Function sqlite3TableLock() is used to add entries to the
2106 ** list.
2107 */
2108 struct Parse {
2109   sqlite3 *db;         /* The main database structure */
2110   int rc;              /* Return code from execution */
2111   char *zErrMsg;       /* An error message */
2112   Vdbe *pVdbe;         /* An engine for executing database bytecode */
2113   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
2114   u8 nameClash;        /* A permanent table name clashes with temp table name */
2115   u8 checkSchema;      /* Causes schema cookie check after an error */
2116   u8 nested;           /* Number of nested calls to the parser/code generator */
2117   u8 parseError;       /* True after a parsing error.  Ticket #1794 */
2118   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
2119   u8 nTempInUse;       /* Number of aTempReg[] currently checked out */
2120   int aTempReg[8];     /* Holding area for temporary registers */
2121   int nRangeReg;       /* Size of the temporary register block */
2122   int iRangeReg;       /* First register in temporary register block */
2123   int nErr;            /* Number of errors seen */
2124   int nTab;            /* Number of previously allocated VDBE cursors */
2125   int nMem;            /* Number of memory cells used so far */
2126   int nSet;            /* Number of sets used so far */
2127   int ckBase;          /* Base register of data during check constraints */
2128   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
2129   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
2130   u8 nColCache;        /* Number of entries in the column cache */
2131   u8 iColCache;        /* Next entry of the cache to replace */
2132   struct yColCache {
2133     int iTable;           /* Table cursor number */
2134     int iColumn;          /* Table column number */
2135     u8 tempReg;           /* iReg is a temp register that needs to be freed */
2136     int iLevel;           /* Nesting level */
2137     int iReg;             /* Reg with value of this column. 0 means none. */
2138     int lru;              /* Least recently used entry has the smallest value */
2139   } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
2140   u32 writeMask;       /* Start a write transaction on these databases */
2141   u32 cookieMask;      /* Bitmask of schema verified databases */
2142   u8 isMultiWrite;     /* True if statement may affect/insert multiple rows */
2143   u8 mayAbort;         /* True if statement may throw an ABORT exception */
2144   int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
2145   int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
2146 #ifndef SQLITE_OMIT_SHARED_CACHE
2147   int nTableLock;        /* Number of locks in aTableLock */
2148   TableLock *aTableLock; /* Required table locks for shared-cache mode */
2149 #endif
2150   int regRowid;        /* Register holding rowid of CREATE TABLE entry */
2151   int regRoot;         /* Register holding root page number for new objects */
2152   AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
2153   int nMaxArg;         /* Max args passed to user function by sub-program */
2154 
2155   /* Information used while coding trigger programs. */
2156   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
2157   Table *pTriggerTab;  /* Table triggers are being coded for */
2158   u32 oldmask;         /* Mask of old.* columns referenced */
2159   u32 newmask;         /* Mask of new.* columns referenced */
2160   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
2161   u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
2162   u8 disableTriggers;  /* True to disable triggers */
2163   double nQueryLoop;   /* Estimated number of iterations of a query */
2164 
2165   /* Above is constant between recursions.  Below is reset before and after
2166   ** each recursion */
2167 
2168   int nVar;            /* Number of '?' variables seen in the SQL so far */
2169   int nVarExpr;        /* Number of used slots in apVarExpr[] */
2170   int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
2171   Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
2172   Vdbe *pReprepare;    /* VM being reprepared (sqlite3Reprepare()) */
2173   int nAlias;          /* Number of aliased result set columns */
2174   int nAliasAlloc;     /* Number of allocated slots for aAlias[] */
2175   int *aAlias;         /* Register used to hold aliased result */
2176   u8 explain;          /* True if the EXPLAIN flag is found on the query */
2177   Token sNameToken;    /* Token with unqualified schema object name */
2178   Token sLastToken;    /* The last token parsed */
2179   const char *zTail;   /* All SQL text past the last semicolon parsed */
2180   Table *pNewTable;    /* A table being constructed by CREATE TABLE */
2181   Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
2182   const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
2183 #ifndef SQLITE_OMIT_VIRTUALTABLE
2184   Token sArg;                /* Complete text of a module argument */
2185   u8 declareVtab;            /* True if inside sqlite3_declare_vtab() */
2186   int nVtabLock;             /* Number of virtual tables to lock */
2187   Table **apVtabLock;        /* Pointer to virtual tables needing locking */
2188 #endif
2189   int nHeight;            /* Expression tree height of current sub-select */
2190   Table *pZombieTab;      /* List of Table objects to delete after code gen */
2191   TriggerPrg *pTriggerPrg;    /* Linked list of coded triggers */
2192 };
2193 
2194 #ifdef SQLITE_OMIT_VIRTUALTABLE
2195   #define IN_DECLARE_VTAB 0
2196 #else
2197   #define IN_DECLARE_VTAB (pParse->declareVtab)
2198 #endif
2199 
2200 /*
2201 ** An instance of the following structure can be declared on a stack and used
2202 ** to save the Parse.zAuthContext value so that it can be restored later.
2203 */
2204 struct AuthContext {
2205   const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
2206   Parse *pParse;              /* The Parse structure */
2207 };
2208 
2209 /*
2210 ** Bitfield flags for P5 value in OP_Insert and OP_Delete
2211 */
2212 #define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
2213 #define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
2214 #define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
2215 #define OPFLAG_APPEND        0x08    /* This is likely to be an append */
2216 #define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
2217 #define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
2218 
2219 /*
2220  * Each trigger present in the database schema is stored as an instance of
2221  * struct Trigger.
2222  *
2223  * Pointers to instances of struct Trigger are stored in two ways.
2224  * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
2225  *    database). This allows Trigger structures to be retrieved by name.
2226  * 2. All triggers associated with a single table form a linked list, using the
2227  *    pNext member of struct Trigger. A pointer to the first element of the
2228  *    linked list is stored as the "pTrigger" member of the associated
2229  *    struct Table.
2230  *
2231  * The "step_list" member points to the first element of a linked list
2232  * containing the SQL statements specified as the trigger program.
2233  */
2234 struct Trigger {
2235   char *zName;            /* The name of the trigger                        */
2236   char *table;            /* The table or view to which the trigger applies */
2237   u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
2238   u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
2239   Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
2240   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
2241                              the <column-list> is stored here */
2242   Schema *pSchema;        /* Schema containing the trigger */
2243   Schema *pTabSchema;     /* Schema containing the table */
2244   TriggerStep *step_list; /* Link list of trigger program steps             */
2245   Trigger *pNext;         /* Next trigger associated with the table */
2246 };
2247 
2248 /*
2249 ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
2250 ** determine which.
2251 **
2252 ** If there are multiple triggers, you might of some BEFORE and some AFTER.
2253 ** In that cases, the constants below can be ORed together.
2254 */
2255 #define TRIGGER_BEFORE  1
2256 #define TRIGGER_AFTER   2
2257 
2258 /*
2259  * An instance of struct TriggerStep is used to store a single SQL statement
2260  * that is a part of a trigger-program.
2261  *
2262  * Instances of struct TriggerStep are stored in a singly linked list (linked
2263  * using the "pNext" member) referenced by the "step_list" member of the
2264  * associated struct Trigger instance. The first element of the linked list is
2265  * the first step of the trigger-program.
2266  *
2267  * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
2268  * "SELECT" statement. The meanings of the other members is determined by the
2269  * value of "op" as follows:
2270  *
2271  * (op == TK_INSERT)
2272  * orconf    -> stores the ON CONFLICT algorithm
2273  * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
2274  *              this stores a pointer to the SELECT statement. Otherwise NULL.
2275  * target    -> A token holding the quoted name of the table to insert into.
2276  * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
2277  *              this stores values to be inserted. Otherwise NULL.
2278  * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ...
2279  *              statement, then this stores the column-names to be
2280  *              inserted into.
2281  *
2282  * (op == TK_DELETE)
2283  * target    -> A token holding the quoted name of the table to delete from.
2284  * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
2285  *              Otherwise NULL.
2286  *
2287  * (op == TK_UPDATE)
2288  * target    -> A token holding the quoted name of the table to update rows of.
2289  * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
2290  *              Otherwise NULL.
2291  * pExprList -> A list of the columns to update and the expressions to update
2292  *              them to. See sqlite3Update() documentation of "pChanges"
2293  *              argument.
2294  *
2295  */
2296 struct TriggerStep {
2297   u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
2298   u8 orconf;           /* OE_Rollback etc. */
2299   Trigger *pTrig;      /* The trigger that this step is a part of */
2300   Select *pSelect;     /* SELECT statment or RHS of INSERT INTO .. SELECT ... */
2301   Token target;        /* Target table for DELETE, UPDATE, INSERT */
2302   Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
2303   ExprList *pExprList; /* SET clause for UPDATE.  VALUES clause for INSERT */
2304   IdList *pIdList;     /* Column names for INSERT */
2305   TriggerStep *pNext;  /* Next in the link-list */
2306   TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
2307 };
2308 
2309 /*
2310 ** The following structure contains information used by the sqliteFix...
2311 ** routines as they walk the parse tree to make database references
2312 ** explicit.
2313 */
2314 typedef struct DbFixer DbFixer;
2315 struct DbFixer {
2316   Parse *pParse;      /* The parsing context.  Error messages written here */
2317   const char *zDb;    /* Make sure all objects are contained in this database */
2318   const char *zType;  /* Type of the container - used for error messages */
2319   const Token *pName; /* Name of the container - used for error messages */
2320 };
2321 
2322 /*
2323 ** An objected used to accumulate the text of a string where we
2324 ** do not necessarily know how big the string will be in the end.
2325 */
2326 struct StrAccum {
2327   sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
2328   char *zBase;         /* A base allocation.  Not from malloc. */
2329   char *zText;         /* The string collected so far */
2330   int  nChar;          /* Length of the string so far */
2331   int  nAlloc;         /* Amount of space allocated in zText */
2332   int  mxAlloc;        /* Maximum allowed string length */
2333   u8   mallocFailed;   /* Becomes true if any memory allocation fails */
2334   u8   useMalloc;      /* True if zText is enlargeable using realloc */
2335   u8   tooBig;         /* Becomes true if string size exceeds limits */
2336 };
2337 
2338 /*
2339 ** A pointer to this structure is used to communicate information
2340 ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
2341 */
2342 typedef struct {
2343   sqlite3 *db;        /* The database being initialized */
2344   int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
2345   char **pzErrMsg;    /* Error message stored here */
2346   int rc;             /* Result code stored here */
2347 } InitData;
2348 
2349 /*
2350 ** Structure containing global configuration data for the SQLite library.
2351 **
2352 ** This structure also contains some state information.
2353 */
2354 struct Sqlite3Config {
2355   int bMemstat;                     /* True to enable memory status */
2356   int bCoreMutex;                   /* True to enable core mutexing */
2357   int bFullMutex;                   /* True to enable full mutexing */
2358   int mxStrlen;                     /* Maximum string length */
2359   int szLookaside;                  /* Default lookaside buffer size */
2360   int nLookaside;                   /* Default lookaside buffer count */
2361   sqlite3_mem_methods m;            /* Low-level memory allocation interface */
2362   sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
2363   sqlite3_pcache_methods pcache;    /* Low-level page-cache interface */
2364   void *pHeap;                      /* Heap storage space */
2365   int nHeap;                        /* Size of pHeap[] */
2366   int mnReq, mxReq;                 /* Min and max heap requests sizes */
2367   void *pScratch;                   /* Scratch memory */
2368   int szScratch;                    /* Size of each scratch buffer */
2369   int nScratch;                     /* Number of scratch buffers */
2370   void *pPage;                      /* Page cache memory */
2371   int szPage;                       /* Size of each page in pPage[] */
2372   int nPage;                        /* Number of pages in pPage[] */
2373   int mxParserStack;                /* maximum depth of the parser stack */
2374   int sharedCacheEnabled;           /* true if shared-cache mode enabled */
2375   /* The above might be initialized to non-zero.  The following need to always
2376   ** initially be zero, however. */
2377   int isInit;                       /* True after initialization has finished */
2378   int inProgress;                   /* True while initialization in progress */
2379   int isMutexInit;                  /* True after mutexes are initialized */
2380   int isMallocInit;                 /* True after malloc is initialized */
2381   int isPCacheInit;                 /* True after malloc is initialized */
2382   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
2383   int nRefInitMutex;                /* Number of users of pInitMutex */
2384   void (*xLog)(void*,int,const char*); /* Function for logging */
2385   void *pLogArg;                       /* First argument to xLog() */
2386 };
2387 
2388 /*
2389 ** Context pointer passed down through the tree-walk.
2390 */
2391 struct Walker {
2392   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
2393   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
2394   Parse *pParse;                            /* Parser context.  */
2395   union {                                   /* Extra data for callback */
2396     NameContext *pNC;                          /* Naming context */
2397     int i;                                     /* Integer value */
2398   } u;
2399 };
2400 
2401 /* Forward declarations */
2402 int sqlite3WalkExpr(Walker*, Expr*);
2403 int sqlite3WalkExprList(Walker*, ExprList*);
2404 int sqlite3WalkSelect(Walker*, Select*);
2405 int sqlite3WalkSelectExpr(Walker*, Select*);
2406 int sqlite3WalkSelectFrom(Walker*, Select*);
2407 
2408 /*
2409 ** Return code from the parse-tree walking primitives and their
2410 ** callbacks.
2411 */
2412 #define WRC_Continue    0   /* Continue down into children */
2413 #define WRC_Prune       1   /* Omit children but continue walking siblings */
2414 #define WRC_Abort       2   /* Abandon the tree walk */
2415 
2416 /*
2417 ** Assuming zIn points to the first byte of a UTF-8 character,
2418 ** advance zIn to point to the first byte of the next UTF-8 character.
2419 */
2420 #define SQLITE_SKIP_UTF8(zIn) {                        \
2421   if( (*(zIn++))>=0xc0 ){                              \
2422     while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
2423   }                                                    \
2424 }
2425 
2426 /*
2427 ** The SQLITE_*_BKPT macros are substitutes for the error codes with
2428 ** the same name but without the _BKPT suffix.  These macros invoke
2429 ** routines that report the line-number on which the error originated
2430 ** using sqlite3_log().  The routines also provide a convenient place
2431 ** to set a debugger breakpoint.
2432 */
2433 int sqlite3CorruptError(int);
2434 int sqlite3MisuseError(int);
2435 int sqlite3CantopenError(int);
2436 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
2437 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
2438 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
2439 
2440 
2441 /*
2442 ** FTS4 is really an extension for FTS3.  It is enabled using the
2443 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also all
2444 ** the SQLITE_ENABLE_FTS4 macro to serve as an alisse for SQLITE_ENABLE_FTS3.
2445 */
2446 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
2447 # define SQLITE_ENABLE_FTS3
2448 #endif
2449 
2450 /*
2451 ** The ctype.h header is needed for non-ASCII systems.  It is also
2452 ** needed by FTS3 when FTS3 is included in the amalgamation.
2453 */
2454 #if !defined(SQLITE_ASCII) || \
2455     (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
2456 # include <ctype.h>
2457 #endif
2458 
2459 /*
2460 ** The following macros mimic the standard library functions toupper(),
2461 ** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
2462 ** sqlite versions only work for ASCII characters, regardless of locale.
2463 */
2464 #ifdef SQLITE_ASCII
2465 # define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
2466 # define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
2467 # define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
2468 # define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
2469 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
2470 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
2471 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
2472 #else
2473 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
2474 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
2475 # define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
2476 # define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
2477 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
2478 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
2479 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
2480 #endif
2481 
2482 /*
2483 ** Internal function prototypes
2484 */
2485 int sqlite3StrICmp(const char *, const char *);
2486 int sqlite3IsNumber(const char*, int*, u8);
2487 int sqlite3Strlen30(const char*);
2488 #define sqlite3StrNICmp sqlite3_strnicmp
2489 
2490 int sqlite3MallocInit(void);
2491 void sqlite3MallocEnd(void);
2492 void *sqlite3Malloc(int);
2493 void *sqlite3MallocZero(int);
2494 void *sqlite3DbMallocZero(sqlite3*, int);
2495 void *sqlite3DbMallocRaw(sqlite3*, int);
2496 char *sqlite3DbStrDup(sqlite3*,const char*);
2497 char *sqlite3DbStrNDup(sqlite3*,const char*, int);
2498 void *sqlite3Realloc(void*, int);
2499 void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
2500 void *sqlite3DbRealloc(sqlite3 *, void *, int);
2501 void sqlite3DbFree(sqlite3*, void*);
2502 int sqlite3MallocSize(void*);
2503 int sqlite3DbMallocSize(sqlite3*, void*);
2504 void *sqlite3ScratchMalloc(int);
2505 void sqlite3ScratchFree(void*);
2506 void *sqlite3PageMalloc(int);
2507 void sqlite3PageFree(void*);
2508 void sqlite3MemSetDefault(void);
2509 void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
2510 int sqlite3MemoryAlarm(void (*)(void*, sqlite3_int64, int), void*, sqlite3_int64);
2511 
2512 /*
2513 ** On systems with ample stack space and that support alloca(), make
2514 ** use of alloca() to obtain space for large automatic objects.  By default,
2515 ** obtain space from malloc().
2516 **
2517 ** The alloca() routine never returns NULL.  This will cause code paths
2518 ** that deal with sqlite3StackAlloc() failures to be unreachable.
2519 */
2520 #ifdef SQLITE_USE_ALLOCA
2521 # define sqlite3StackAllocRaw(D,N)   alloca(N)
2522 # define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
2523 # define sqlite3StackFree(D,P)
2524 #else
2525 # define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
2526 # define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
2527 # define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
2528 #endif
2529 
2530 #ifdef SQLITE_ENABLE_MEMSYS3
2531 const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
2532 #endif
2533 #ifdef SQLITE_ENABLE_MEMSYS5
2534 const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
2535 #endif
2536 
2537 
2538 #ifndef SQLITE_MUTEX_OMIT
2539   sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
2540   sqlite3_mutex_methods const *sqlite3NoopMutex(void);
2541   sqlite3_mutex *sqlite3MutexAlloc(int);
2542   int sqlite3MutexInit(void);
2543   int sqlite3MutexEnd(void);
2544 #endif
2545 
2546 int sqlite3StatusValue(int);
2547 void sqlite3StatusAdd(int, int);
2548 void sqlite3StatusSet(int, int);
2549 
2550 #ifndef SQLITE_OMIT_FLOATING_POINT
2551   int sqlite3IsNaN(double);
2552 #else
2553 # define sqlite3IsNaN(X)  0
2554 #endif
2555 
2556 void sqlite3VXPrintf(StrAccum*, int, const char*, va_list);
2557 #ifndef SQLITE_OMIT_TRACE
2558 void sqlite3XPrintf(StrAccum*, const char*, ...);
2559 #endif
2560 char *sqlite3MPrintf(sqlite3*,const char*, ...);
2561 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
2562 char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
2563 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
2564   void sqlite3DebugPrintf(const char*, ...);
2565 #endif
2566 #if defined(SQLITE_TEST)
2567   void *sqlite3TestTextToPtr(const char*);
2568 #endif
2569 void sqlite3SetString(char **, sqlite3*, const char*, ...);
2570 void sqlite3ErrorMsg(Parse*, const char*, ...);
2571 int sqlite3Dequote(char*);
2572 int sqlite3KeywordCode(const unsigned char*, int);
2573 int sqlite3RunParser(Parse*, const char*, char **);
2574 void sqlite3FinishCoding(Parse*);
2575 int sqlite3GetTempReg(Parse*);
2576 void sqlite3ReleaseTempReg(Parse*,int);
2577 int sqlite3GetTempRange(Parse*,int);
2578 void sqlite3ReleaseTempRange(Parse*,int,int);
2579 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
2580 Expr *sqlite3Expr(sqlite3*,int,const char*);
2581 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
2582 Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
2583 Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
2584 Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
2585 void sqlite3ExprAssignVarNumber(Parse*, Expr*);
2586 void sqlite3ExprDelete(sqlite3*, Expr*);
2587 ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
2588 void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
2589 void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
2590 void sqlite3ExprListDelete(sqlite3*, ExprList*);
2591 int sqlite3Init(sqlite3*, char**);
2592 int sqlite3InitCallback(void*, int, char**, char**);
2593 void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
2594 void sqlite3ResetInternalSchema(sqlite3*, int);
2595 void sqlite3BeginParse(Parse*,int);
2596 void sqlite3CommitInternalChanges(sqlite3*);
2597 Table *sqlite3ResultSetOfSelect(Parse*,Select*);
2598 void sqlite3OpenMasterTable(Parse *, int);
2599 void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
2600 void sqlite3AddColumn(Parse*,Token*);
2601 void sqlite3AddNotNull(Parse*, int);
2602 void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
2603 void sqlite3AddCheckConstraint(Parse*, Expr*);
2604 void sqlite3AddColumnType(Parse*,Token*);
2605 void sqlite3AddDefaultValue(Parse*,ExprSpan*);
2606 void sqlite3AddCollateType(Parse*, Token*);
2607 void sqlite3EndTable(Parse*,Token*,Token*,Select*);
2608 
2609 Bitvec *sqlite3BitvecCreate(u32);
2610 int sqlite3BitvecTest(Bitvec*, u32);
2611 int sqlite3BitvecSet(Bitvec*, u32);
2612 void sqlite3BitvecClear(Bitvec*, u32, void*);
2613 void sqlite3BitvecDestroy(Bitvec*);
2614 u32 sqlite3BitvecSize(Bitvec*);
2615 int sqlite3BitvecBuiltinTest(int,int*);
2616 
2617 RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
2618 void sqlite3RowSetClear(RowSet*);
2619 void sqlite3RowSetInsert(RowSet*, i64);
2620 int sqlite3RowSetTest(RowSet*, u8 iBatch, i64);
2621 int sqlite3RowSetNext(RowSet*, i64*);
2622 
2623 void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
2624 
2625 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
2626   int sqlite3ViewGetColumnNames(Parse*,Table*);
2627 #else
2628 # define sqlite3ViewGetColumnNames(A,B) 0
2629 #endif
2630 
2631 void sqlite3DropTable(Parse*, SrcList*, int, int);
2632 void sqlite3DeleteTable(Table*);
2633 #ifndef SQLITE_OMIT_AUTOINCREMENT
2634   void sqlite3AutoincrementBegin(Parse *pParse);
2635   void sqlite3AutoincrementEnd(Parse *pParse);
2636 #else
2637 # define sqlite3AutoincrementBegin(X)
2638 # define sqlite3AutoincrementEnd(X)
2639 #endif
2640 void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
2641 void *sqlite3ArrayAllocate(sqlite3*,void*,int,int,int*,int*,int*);
2642 IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
2643 int sqlite3IdListIndex(IdList*,const char*);
2644 SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
2645 SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
2646 SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
2647                                       Token*, Select*, Expr*, IdList*);
2648 void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
2649 int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
2650 void sqlite3SrcListShiftJoinType(SrcList*);
2651 void sqlite3SrcListAssignCursors(Parse*, SrcList*);
2652 void sqlite3IdListDelete(sqlite3*, IdList*);
2653 void sqlite3SrcListDelete(sqlite3*, SrcList*);
2654 Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
2655                         Token*, int, int);
2656 void sqlite3DropIndex(Parse*, SrcList*, int);
2657 int sqlite3Select(Parse*, Select*, SelectDest*);
2658 Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
2659                          Expr*,ExprList*,int,Expr*,Expr*);
2660 void sqlite3SelectDelete(sqlite3*, Select*);
2661 Table *sqlite3SrcListLookup(Parse*, SrcList*);
2662 int sqlite3IsReadOnly(Parse*, Table*, int);
2663 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
2664 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
2665 Expr *sqlite3LimitWhere(Parse *, SrcList *, Expr *, ExprList *, Expr *, Expr *, char *);
2666 #endif
2667 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
2668 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
2669 WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**, u16);
2670 void sqlite3WhereEnd(WhereInfo*);
2671 int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int);
2672 void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
2673 void sqlite3ExprCodeMove(Parse*, int, int, int);
2674 void sqlite3ExprCodeCopy(Parse*, int, int, int);
2675 void sqlite3ExprCacheStore(Parse*, int, int, int);
2676 void sqlite3ExprCachePush(Parse*);
2677 void sqlite3ExprCachePop(Parse*, int);
2678 void sqlite3ExprCacheRemove(Parse*, int, int);
2679 void sqlite3ExprCacheClear(Parse*);
2680 void sqlite3ExprCacheAffinityChange(Parse*, int, int);
2681 void sqlite3ExprHardCopy(Parse*,int,int);
2682 int sqlite3ExprCode(Parse*, Expr*, int);
2683 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
2684 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
2685 int sqlite3ExprCodeAndCache(Parse*, Expr*, int);
2686 void sqlite3ExprCodeConstants(Parse*, Expr*);
2687 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int);
2688 void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
2689 void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
2690 Table *sqlite3FindTable(sqlite3*,const char*, const char*);
2691 Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
2692 Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
2693 void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
2694 void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
2695 void sqlite3Vacuum(Parse*);
2696 int sqlite3RunVacuum(char**, sqlite3*);
2697 char *sqlite3NameFromToken(sqlite3*, Token*);
2698 int sqlite3ExprCompare(Expr*, Expr*);
2699 int sqlite3ExprListCompare(ExprList*, ExprList*);
2700 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
2701 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
2702 Vdbe *sqlite3GetVdbe(Parse*);
2703 void sqlite3PrngSaveState(void);
2704 void sqlite3PrngRestoreState(void);
2705 void sqlite3PrngResetState(void);
2706 void sqlite3RollbackAll(sqlite3*);
2707 void sqlite3CodeVerifySchema(Parse*, int);
2708 void sqlite3BeginTransaction(Parse*, int);
2709 void sqlite3CommitTransaction(Parse*);
2710 void sqlite3RollbackTransaction(Parse*);
2711 void sqlite3Savepoint(Parse*, int, Token*);
2712 void sqlite3CloseSavepoints(sqlite3 *);
2713 int sqlite3ExprIsConstant(Expr*);
2714 int sqlite3ExprIsConstantNotJoin(Expr*);
2715 int sqlite3ExprIsConstantOrFunction(Expr*);
2716 int sqlite3ExprIsInteger(Expr*, int*);
2717 int sqlite3ExprCanBeNull(const Expr*);
2718 void sqlite3ExprCodeIsNullJump(Vdbe*, const Expr*, int, int);
2719 int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
2720 int sqlite3IsRowid(const char*);
2721 void sqlite3GenerateRowDelete(Parse*, Table*, int, int, int, Trigger *, int);
2722 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int*);
2723 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int);
2724 void sqlite3GenerateConstraintChecks(Parse*,Table*,int,int,
2725                                      int*,int,int,int,int,int*);
2726 void sqlite3CompleteInsertion(Parse*, Table*, int, int, int*, int, int, int);
2727 int sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
2728 void sqlite3BeginWriteOperation(Parse*, int, int);
2729 void sqlite3MultiWrite(Parse*);
2730 void sqlite3MayAbort(Parse*);
2731 void sqlite3HaltConstraint(Parse*, int, char*, int);
2732 Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
2733 ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
2734 SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
2735 IdList *sqlite3IdListDup(sqlite3*,IdList*);
2736 Select *sqlite3SelectDup(sqlite3*,Select*,int);
2737 void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
2738 FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);
2739 void sqlite3RegisterBuiltinFunctions(sqlite3*);
2740 void sqlite3RegisterDateTimeFunctions(void);
2741 void sqlite3RegisterGlobalFunctions(void);
2742 int sqlite3SafetyCheckOk(sqlite3*);
2743 int sqlite3SafetyCheckSickOrOk(sqlite3*);
2744 void sqlite3ChangeCookie(Parse*, int);
2745 
2746 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
2747 void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
2748 #endif
2749 
2750 #ifndef SQLITE_OMIT_TRIGGER
2751   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
2752                            Expr*,int, int);
2753   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
2754   void sqlite3DropTrigger(Parse*, SrcList*, int);
2755   void sqlite3DropTriggerPtr(Parse*, Trigger*);
2756   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
2757   Trigger *sqlite3TriggerList(Parse *, Table *);
2758   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
2759                             int, int, int);
2760   void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
2761   void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
2762   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
2763   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
2764   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
2765                                         ExprList*,Select*,u8);
2766   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
2767   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
2768   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
2769   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
2770   u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
2771 # define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
2772 #else
2773 # define sqlite3TriggersExist(B,C,D,E,F) 0
2774 # define sqlite3DeleteTrigger(A,B)
2775 # define sqlite3DropTriggerPtr(A,B)
2776 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
2777 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
2778 # define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
2779 # define sqlite3TriggerList(X, Y) 0
2780 # define sqlite3ParseToplevel(p) p
2781 # define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
2782 #endif
2783 
2784 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
2785 void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
2786 void sqlite3DeferForeignKey(Parse*, int);
2787 #ifndef SQLITE_OMIT_AUTHORIZATION
2788   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
2789   int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
2790   void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
2791   void sqlite3AuthContextPop(AuthContext*);
2792   int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
2793 #else
2794 # define sqlite3AuthRead(a,b,c,d)
2795 # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
2796 # define sqlite3AuthContextPush(a,b,c)
2797 # define sqlite3AuthContextPop(a)  ((void)(a))
2798 #endif
2799 void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
2800 void sqlite3Detach(Parse*, Expr*);
2801 int sqlite3BtreeFactory(sqlite3 *db, const char *zFilename,
2802                        int omitJournal, int nCache, int flags, Btree **ppBtree);
2803 int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
2804 int sqlite3FixSrcList(DbFixer*, SrcList*);
2805 int sqlite3FixSelect(DbFixer*, Select*);
2806 int sqlite3FixExpr(DbFixer*, Expr*);
2807 int sqlite3FixExprList(DbFixer*, ExprList*);
2808 int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
2809 int sqlite3AtoF(const char *z, double*);
2810 int sqlite3GetInt32(const char *, int*);
2811 int sqlite3FitsIn64Bits(const char *, int);
2812 int sqlite3Utf16ByteLen(const void *pData, int nChar);
2813 int sqlite3Utf8CharLen(const char *pData, int nByte);
2814 int sqlite3Utf8Read(const u8*, const u8**);
2815 
2816 /*
2817 ** Routines to read and write variable-length integers.  These used to
2818 ** be defined locally, but now we use the varint routines in the util.c
2819 ** file.  Code should use the MACRO forms below, as the Varint32 versions
2820 ** are coded to assume the single byte case is already handled (which
2821 ** the MACRO form does).
2822 */
2823 int sqlite3PutVarint(unsigned char*, u64);
2824 int sqlite3PutVarint32(unsigned char*, u32);
2825 u8 sqlite3GetVarint(const unsigned char *, u64 *);
2826 u8 sqlite3GetVarint32(const unsigned char *, u32 *);
2827 int sqlite3VarintLen(u64 v);
2828 
2829 /*
2830 ** The header of a record consists of a sequence variable-length integers.
2831 ** These integers are almost always small and are encoded as a single byte.
2832 ** The following macros take advantage this fact to provide a fast encode
2833 ** and decode of the integers in a record header.  It is faster for the common
2834 ** case where the integer is a single byte.  It is a little slower when the
2835 ** integer is two or more bytes.  But overall it is faster.
2836 **
2837 ** The following expressions are equivalent:
2838 **
2839 **     x = sqlite3GetVarint32( A, &B );
2840 **     x = sqlite3PutVarint32( A, B );
2841 **
2842 **     x = getVarint32( A, B );
2843 **     x = putVarint32( A, B );
2844 **
2845 */
2846 #define getVarint32(A,B)  (u8)((*(A)<(u8)0x80) ? ((B) = (u32)*(A)),1 : sqlite3GetVarint32((A), (u32 *)&(B)))
2847 #define putVarint32(A,B)  (u8)(((u32)(B)<(u32)0x80) ? (*(A) = (unsigned char)(B)),1 : sqlite3PutVarint32((A), (B)))
2848 #define getVarint    sqlite3GetVarint
2849 #define putVarint    sqlite3PutVarint
2850 
2851 
2852 const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
2853 void sqlite3TableAffinityStr(Vdbe *, Table *);
2854 char sqlite3CompareAffinity(Expr *pExpr, char aff2);
2855 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
2856 char sqlite3ExprAffinity(Expr *pExpr);
2857 int sqlite3Atoi64(const char*, i64*);
2858 void sqlite3Error(sqlite3*, int, const char*,...);
2859 void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
2860 int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
2861 const char *sqlite3ErrStr(int);
2862 int sqlite3ReadSchema(Parse *pParse);
2863 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
2864 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
2865 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
2866 Expr *sqlite3ExprSetColl(Parse *pParse, Expr *, Token *);
2867 int sqlite3CheckCollSeq(Parse *, CollSeq *);
2868 int sqlite3CheckObjectName(Parse *, const char *);
2869 void sqlite3VdbeSetChanges(sqlite3 *, int);
2870 
2871 const void *sqlite3ValueText(sqlite3_value*, u8);
2872 int sqlite3ValueBytes(sqlite3_value*, u8);
2873 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
2874                         void(*)(void*));
2875 void sqlite3ValueFree(sqlite3_value*);
2876 sqlite3_value *sqlite3ValueNew(sqlite3 *);
2877 char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
2878 #ifdef SQLITE_ENABLE_STAT2
2879 char *sqlite3Utf8to16(sqlite3 *, u8, char *, int, int *);
2880 #endif
2881 int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
2882 void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
2883 #ifndef SQLITE_AMALGAMATION
2884 extern const unsigned char sqlite3OpcodeProperty[];
2885 extern const unsigned char sqlite3UpperToLower[];
2886 extern const unsigned char sqlite3CtypeMap[];
2887 extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
2888 extern SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
2889 #ifndef SQLITE_OMIT_WSD
2890 extern int sqlite3PendingByte;
2891 #endif
2892 #endif
2893 void sqlite3RootPageMoved(Db*, int, int);
2894 void sqlite3Reindex(Parse*, Token*, Token*);
2895 void sqlite3AlterFunctions(void);
2896 void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
2897 int sqlite3GetToken(const unsigned char *, int *);
2898 void sqlite3NestedParse(Parse*, const char*, ...);
2899 void sqlite3ExpirePreparedStatements(sqlite3*);
2900 int sqlite3CodeSubselect(Parse *, Expr *, int, int);
2901 void sqlite3SelectPrep(Parse*, Select*, NameContext*);
2902 int sqlite3ResolveExprNames(NameContext*, Expr*);
2903 void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
2904 int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
2905 void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
2906 void sqlite3AlterFinishAddColumn(Parse *, Token *);
2907 void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
2908 CollSeq *sqlite3GetCollSeq(sqlite3*, u8, CollSeq *, const char*);
2909 char sqlite3AffinityType(const char*);
2910 void sqlite3Analyze(Parse*, Token*, Token*);
2911 int sqlite3InvokeBusyHandler(BusyHandler*);
2912 int sqlite3FindDb(sqlite3*, Token*);
2913 int sqlite3FindDbName(sqlite3 *, const char *);
2914 int sqlite3AnalysisLoad(sqlite3*,int iDB);
2915 void sqlite3DeleteIndexSamples(Index*);
2916 void sqlite3DefaultRowEst(Index*);
2917 void sqlite3RegisterLikeFunctions(sqlite3*, int);
2918 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
2919 void sqlite3MinimumFileFormat(Parse*, int, int);
2920 void sqlite3SchemaFree(void *);
2921 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
2922 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
2923 KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
2924 int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
2925   void (*)(sqlite3_context*,int,sqlite3_value **),
2926   void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*));
2927 int sqlite3ApiExit(sqlite3 *db, int);
2928 int sqlite3OpenTempDatabase(Parse *);
2929 
2930 void sqlite3StrAccumInit(StrAccum*, char*, int, int);
2931 void sqlite3StrAccumAppend(StrAccum*,const char*,int);
2932 char *sqlite3StrAccumFinish(StrAccum*);
2933 void sqlite3StrAccumReset(StrAccum*);
2934 void sqlite3SelectDestInit(SelectDest*,int,int);
2935 Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
2936 
2937 void sqlite3BackupRestart(sqlite3_backup *);
2938 void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
2939 
2940 /*
2941 ** The interface to the LEMON-generated parser
2942 */
2943 void *sqlite3ParserAlloc(void*(*)(size_t));
2944 void sqlite3ParserFree(void*, void(*)(void*));
2945 void sqlite3Parser(void*, int, Token, Parse*);
2946 #ifdef YYTRACKMAXSTACKDEPTH
2947   int sqlite3ParserStackPeak(void*);
2948 #endif
2949 
2950 void sqlite3AutoLoadExtensions(sqlite3*);
2951 #ifndef SQLITE_OMIT_LOAD_EXTENSION
2952   void sqlite3CloseExtensions(sqlite3*);
2953 #else
2954 # define sqlite3CloseExtensions(X)
2955 #endif
2956 
2957 #ifndef SQLITE_OMIT_SHARED_CACHE
2958   void sqlite3TableLock(Parse *, int, int, u8, const char *);
2959 #else
2960   #define sqlite3TableLock(v,w,x,y,z)
2961 #endif
2962 
2963 #ifdef SQLITE_TEST
2964   int sqlite3Utf8To8(unsigned char*);
2965 #endif
2966 
2967 #ifdef SQLITE_OMIT_VIRTUALTABLE
2968 #  define sqlite3VtabClear(Y)
2969 #  define sqlite3VtabSync(X,Y) SQLITE_OK
2970 #  define sqlite3VtabRollback(X)
2971 #  define sqlite3VtabCommit(X)
2972 #  define sqlite3VtabInSync(db) 0
2973 #  define sqlite3VtabLock(X)
2974 #  define sqlite3VtabUnlock(X)
2975 #  define sqlite3VtabUnlockList(X)
2976 #else
2977    void sqlite3VtabClear(Table*);
2978    int sqlite3VtabSync(sqlite3 *db, char **);
2979    int sqlite3VtabRollback(sqlite3 *db);
2980    int sqlite3VtabCommit(sqlite3 *db);
2981    void sqlite3VtabLock(VTable *);
2982    void sqlite3VtabUnlock(VTable *);
2983    void sqlite3VtabUnlockList(sqlite3*);
2984 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
2985 #endif
2986 void sqlite3VtabMakeWritable(Parse*,Table*);
2987 void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*);
2988 void sqlite3VtabFinishParse(Parse*, Token*);
2989 void sqlite3VtabArgInit(Parse*);
2990 void sqlite3VtabArgExtend(Parse*, Token*);
2991 int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
2992 int sqlite3VtabCallConnect(Parse*, Table*);
2993 int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
2994 int sqlite3VtabBegin(sqlite3 *, VTable *);
2995 FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
2996 void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
2997 int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
2998 int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
2999 int sqlite3Reprepare(Vdbe*);
3000 void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
3001 CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
3002 int sqlite3TempInMemory(const sqlite3*);
3003 VTable *sqlite3GetVTable(sqlite3*, Table*);
3004 const char *sqlite3JournalModename(int);
3005 int sqlite3Checkpoint(sqlite3*, int);
3006 int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
3007 
3008 /* Declarations for functions in fkey.c. All of these are replaced by
3009 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
3010 ** key functionality is available. If OMIT_TRIGGER is defined but
3011 ** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
3012 ** this case foreign keys are parsed, but no other functionality is
3013 ** provided (enforcement of FK constraints requires the triggers sub-system).
3014 */
3015 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
3016   void sqlite3FkCheck(Parse*, Table*, int, int);
3017   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
3018   void sqlite3FkActions(Parse*, Table*, ExprList*, int);
3019   int sqlite3FkRequired(Parse*, Table*, int*, int);
3020   u32 sqlite3FkOldmask(Parse*, Table*);
3021   FKey *sqlite3FkReferences(Table *);
3022 #else
3023   #define sqlite3FkActions(a,b,c,d)
3024   #define sqlite3FkCheck(a,b,c,d)
3025   #define sqlite3FkDropTable(a,b,c)
3026   #define sqlite3FkOldmask(a,b)      0
3027   #define sqlite3FkRequired(a,b,c,d) 0
3028 #endif
3029 #ifndef SQLITE_OMIT_FOREIGN_KEY
3030   void sqlite3FkDelete(Table*);
3031 #else
3032   #define sqlite3FkDelete(a)
3033 #endif
3034 
3035 
3036 /*
3037 ** Available fault injectors.  Should be numbered beginning with 0.
3038 */
3039 #define SQLITE_FAULTINJECTOR_MALLOC     0
3040 #define SQLITE_FAULTINJECTOR_COUNT      1
3041 
3042 /*
3043 ** The interface to the code in fault.c used for identifying "benign"
3044 ** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
3045 ** is not defined.
3046 */
3047 #ifndef SQLITE_OMIT_BUILTIN_TEST
3048   void sqlite3BeginBenignMalloc(void);
3049   void sqlite3EndBenignMalloc(void);
3050 #else
3051   #define sqlite3BeginBenignMalloc()
3052   #define sqlite3EndBenignMalloc()
3053 #endif
3054 
3055 #define IN_INDEX_ROWID           1
3056 #define IN_INDEX_EPH             2
3057 #define IN_INDEX_INDEX           3
3058 int sqlite3FindInIndex(Parse *, Expr *, int*);
3059 
3060 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
3061   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
3062   int sqlite3JournalSize(sqlite3_vfs *);
3063   int sqlite3JournalCreate(sqlite3_file *);
3064 #else
3065   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
3066 #endif
3067 
3068 void sqlite3MemJournalOpen(sqlite3_file *);
3069 int sqlite3MemJournalSize(void);
3070 int sqlite3IsMemJournal(sqlite3_file *);
3071 
3072 #if SQLITE_MAX_EXPR_DEPTH>0
3073   void sqlite3ExprSetHeight(Parse *pParse, Expr *p);
3074   int sqlite3SelectExprHeight(Select *);
3075   int sqlite3ExprCheckHeight(Parse*, int);
3076 #else
3077   #define sqlite3ExprSetHeight(x,y)
3078   #define sqlite3SelectExprHeight(x) 0
3079   #define sqlite3ExprCheckHeight(x,y)
3080 #endif
3081 
3082 u32 sqlite3Get4byte(const u8*);
3083 void sqlite3Put4byte(u8*, u32);
3084 
3085 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
3086   void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
3087   void sqlite3ConnectionUnlocked(sqlite3 *db);
3088   void sqlite3ConnectionClosed(sqlite3 *db);
3089 #else
3090   #define sqlite3ConnectionBlocked(x,y)
3091   #define sqlite3ConnectionUnlocked(x)
3092   #define sqlite3ConnectionClosed(x)
3093 #endif
3094 
3095 #ifdef SQLITE_DEBUG
3096   void sqlite3ParserTrace(FILE*, char *);
3097 #endif
3098 
3099 /*
3100 ** If the SQLITE_ENABLE IOTRACE exists then the global variable
3101 ** sqlite3IoTrace is a pointer to a printf-like routine used to
3102 ** print I/O tracing messages.
3103 */
3104 #ifdef SQLITE_ENABLE_IOTRACE
3105 # define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
3106   void sqlite3VdbeIOTraceSql(Vdbe*);
3107 SQLITE_EXTERN void (*sqlite3IoTrace)(const char*,...);
3108 #else
3109 # define IOTRACE(A)
3110 # define sqlite3VdbeIOTraceSql(X)
3111 #endif
3112 
3113 /*
3114 ** These routines are available for the mem2.c debugging memory allocator
3115 ** only.  They are used to verify that different "types" of memory
3116 ** allocations are properly tracked by the system.
3117 **
3118 ** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
3119 ** the MEMTYPE_* macros defined below.  The type must be a bitmask with
3120 ** a single bit set.
3121 **
3122 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
3123 ** argument match the type set by the previous sqlite3MemdebugSetType().
3124 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
3125 ** For example:
3126 **
3127 **     assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
3128 **
3129 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
3130 ** and MEMTYPE_DB.  If an allocation is MEMTYPE_DB, that means it might have
3131 ** been allocated by lookaside, except the allocation was too large or
3132 ** lookaside was already full.  It is important to verify that allocations
3133 ** that might have been satisfied by lookaside are not passed back to
3134 ** non-lookaside free() routines.  Asserts such as the example above are
3135 ** placed on the non-lookaside free() routines to verify this constraint.
3136 **
3137 ** All of this is no-op for a production build.  It only comes into
3138 ** play when the SQLITE_MEMDEBUG compile-time option is used.
3139 */
3140 #ifdef SQLITE_MEMDEBUG
3141   void sqlite3MemdebugSetType(void*,u8);
3142   int sqlite3MemdebugHasType(void*,u8);
3143 #else
3144 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
3145 # define sqlite3MemdebugHasType(X,Y)  1
3146 #endif
3147 #define MEMTYPE_HEAP     0x01    /* General heap allocations */
3148 #define MEMTYPE_DB       0x02    /* Associated with a database connection */
3149 #define MEMTYPE_SCRATCH  0x04    /* Scratch allocations */
3150 #define MEMTYPE_PCACHE   0x08    /* Page cache allocations */
3151 
3152 #endif /* _SQLITEINT_H_ */
3153