1 /* 2 ** 2001 September 15 3 ** 4 ** The author disclaims copyright to this source code. In place of 5 ** a legal notice, here is a blessing: 6 ** 7 ** May you do good and not evil. 8 ** May you find forgiveness for yourself and forgive others. 9 ** May you share freely, never taking more than you give. 10 ** 11 ************************************************************************* 12 ** Internal interface definitions for SQLite. 13 ** 14 ** @(#) $Id: sqliteInt.h,v 1.220.2.1 2004/07/15 13:37:05 drh Exp $ 15 */ 16 #include "config.h" 17 #include "sqlite.h" 18 #include "hash.h" 19 #include "parse.h" 20 #include "btree.h" 21 #include <stdio.h> 22 #include <stdlib.h> 23 #include <string.h> 24 #include <assert.h> 25 26 /* 27 ** The maximum number of in-memory pages to use for the main database 28 ** table and for temporary tables. 29 */ 30 #define MAX_PAGES 2000 31 #define TEMP_PAGES 500 32 33 /* 34 ** If the following macro is set to 1, then NULL values are considered 35 ** distinct for the SELECT DISTINCT statement and for UNION or EXCEPT 36 ** compound queries. No other SQL database engine (among those tested) 37 ** works this way except for OCELOT. But the SQL92 spec implies that 38 ** this is how things should work. 39 ** 40 ** If the following macro is set to 0, then NULLs are indistinct for 41 ** SELECT DISTINCT and for UNION. 42 */ 43 #define NULL_ALWAYS_DISTINCT 0 44 45 /* 46 ** If the following macro is set to 1, then NULL values are considered 47 ** distinct when determining whether or not two entries are the same 48 ** in a UNIQUE index. This is the way PostgreSQL, Oracle, DB2, MySQL, 49 ** OCELOT, and Firebird all work. The SQL92 spec explicitly says this 50 ** is the way things are suppose to work. 51 ** 52 ** If the following macro is set to 0, the NULLs are indistinct for 53 ** a UNIQUE index. In this mode, you can only have a single NULL entry 54 ** for a column declared UNIQUE. This is the way Informix and SQL Server 55 ** work. 56 */ 57 #define NULL_DISTINCT_FOR_UNIQUE 1 58 59 /* 60 ** The maximum number of attached databases. This must be at least 2 61 ** in order to support the main database file (0) and the file used to 62 ** hold temporary tables (1). And it must be less than 256 because 63 ** an unsigned character is used to stored the database index. 64 */ 65 #define MAX_ATTACHED 10 66 67 /* 68 ** The next macro is used to determine where TEMP tables and indices 69 ** are stored. Possible values: 70 ** 71 ** 0 Always use a temporary files 72 ** 1 Use a file unless overridden by "PRAGMA temp_store" 73 ** 2 Use memory unless overridden by "PRAGMA temp_store" 74 ** 3 Always use memory 75 */ 76 #ifndef TEMP_STORE 77 # define TEMP_STORE 1 78 #endif 79 80 /* 81 ** When building SQLite for embedded systems where memory is scarce, 82 ** you can define one or more of the following macros to omit extra 83 ** features of the library and thus keep the size of the library to 84 ** a minimum. 85 */ 86 /* #define SQLITE_OMIT_AUTHORIZATION 1 */ 87 /* #define SQLITE_OMIT_INMEMORYDB 1 */ 88 /* #define SQLITE_OMIT_VACUUM 1 */ 89 /* #define SQLITE_OMIT_DATETIME_FUNCS 1 */ 90 /* #define SQLITE_OMIT_PROGRESS_CALLBACK 1 */ 91 92 /* 93 ** Integers of known sizes. These typedefs might change for architectures 94 ** where the sizes very. Preprocessor macros are available so that the 95 ** types can be conveniently redefined at compile-type. Like this: 96 ** 97 ** cc '-DUINTPTR_TYPE=long long int' ... 98 */ 99 #ifndef UINT32_TYPE 100 # define UINT32_TYPE unsigned int 101 #endif 102 #ifndef UINT16_TYPE 103 # define UINT16_TYPE unsigned short int 104 #endif 105 #ifndef INT16_TYPE 106 # define INT16_TYPE short int 107 #endif 108 #ifndef UINT8_TYPE 109 # define UINT8_TYPE unsigned char 110 #endif 111 #ifndef INT8_TYPE 112 # define INT8_TYPE signed char 113 #endif 114 #ifndef INTPTR_TYPE 115 # if SQLITE_PTR_SZ==4 116 # define INTPTR_TYPE int 117 # else 118 # define INTPTR_TYPE long long 119 # endif 120 #endif 121 typedef UINT32_TYPE u32; /* 4-byte unsigned integer */ 122 typedef UINT16_TYPE u16; /* 2-byte unsigned integer */ 123 typedef INT16_TYPE i16; /* 2-byte signed integer */ 124 typedef UINT8_TYPE u8; /* 1-byte unsigned integer */ 125 typedef UINT8_TYPE i8; /* 1-byte signed integer */ 126 typedef INTPTR_TYPE ptr; /* Big enough to hold a pointer */ 127 typedef unsigned INTPTR_TYPE uptr; /* Big enough to hold a pointer */ 128 129 /* 130 ** Defer sourcing vdbe.h until after the "u8" typedef is defined. 131 */ 132 #include "vdbe.h" 133 134 /* 135 ** Most C compilers these days recognize "long double", don't they? 136 ** Just in case we encounter one that does not, we will create a macro 137 ** for long double so that it can be easily changed to just "double". 138 */ 139 #ifndef LONGDOUBLE_TYPE 140 # define LONGDOUBLE_TYPE long double 141 #endif 142 143 /* 144 ** This macro casts a pointer to an integer. Useful for doing 145 ** pointer arithmetic. 146 */ 147 #define Addr(X) ((uptr)X) 148 149 /* 150 ** The maximum number of bytes of data that can be put into a single 151 ** row of a single table. The upper bound on this limit is 16777215 152 ** bytes (or 16MB-1). We have arbitrarily set the limit to just 1MB 153 ** here because the overflow page chain is inefficient for really big 154 ** records and we want to discourage people from thinking that 155 ** multi-megabyte records are OK. If your needs are different, you can 156 ** change this define and recompile to increase or decrease the record 157 ** size. 158 ** 159 ** The 16777198 is computed as follows: 238 bytes of payload on the 160 ** original pages plus 16448 overflow pages each holding 1020 bytes of 161 ** data. 162 */ 163 #define MAX_BYTES_PER_ROW 1048576 164 /* #define MAX_BYTES_PER_ROW 16777198 */ 165 166 /* 167 ** If memory allocation problems are found, recompile with 168 ** 169 ** -DMEMORY_DEBUG=1 170 ** 171 ** to enable some sanity checking on malloc() and free(). To 172 ** check for memory leaks, recompile with 173 ** 174 ** -DMEMORY_DEBUG=2 175 ** 176 ** and a line of text will be written to standard error for 177 ** each malloc() and free(). This output can be analyzed 178 ** by an AWK script to determine if there are any leaks. 179 */ 180 #ifdef MEMORY_DEBUG 181 # define sqliteMalloc(X) sqliteMalloc_(X,1,__FILE__,__LINE__) 182 # define sqliteMallocRaw(X) sqliteMalloc_(X,0,__FILE__,__LINE__) 183 # define sqliteFree(X) sqliteFree_(X,__FILE__,__LINE__) 184 # define sqliteRealloc(X,Y) sqliteRealloc_(X,Y,__FILE__,__LINE__) 185 # define sqliteStrDup(X) sqliteStrDup_(X,__FILE__,__LINE__) 186 # define sqliteStrNDup(X,Y) sqliteStrNDup_(X,Y,__FILE__,__LINE__) 187 void sqliteStrRealloc(char**); 188 #else 189 # define sqliteRealloc_(X,Y) sqliteRealloc(X,Y) 190 # define sqliteStrRealloc(X) 191 #endif 192 193 /* 194 ** This variable gets set if malloc() ever fails. After it gets set, 195 ** the SQLite library shuts down permanently. 196 */ 197 extern int sqlite_malloc_failed; 198 199 /* 200 ** The following global variables are used for testing and debugging 201 ** only. They only work if MEMORY_DEBUG is defined. 202 */ 203 #ifdef MEMORY_DEBUG 204 extern int sqlite_nMalloc; /* Number of sqliteMalloc() calls */ 205 extern int sqlite_nFree; /* Number of sqliteFree() calls */ 206 extern int sqlite_iMallocFail; /* Fail sqliteMalloc() after this many calls */ 207 #endif 208 209 /* 210 ** Name of the master database table. The master database table 211 ** is a special table that holds the names and attributes of all 212 ** user tables and indices. 213 */ 214 #define MASTER_NAME "sqlite_master" 215 #define TEMP_MASTER_NAME "sqlite_temp_master" 216 217 /* 218 ** The name of the schema table. 219 */ 220 #define SCHEMA_TABLE(x) (x?TEMP_MASTER_NAME:MASTER_NAME) 221 222 /* 223 ** A convenience macro that returns the number of elements in 224 ** an array. 225 */ 226 #define ArraySize(X) (sizeof(X)/sizeof(X[0])) 227 228 /* 229 ** Forward references to structures 230 */ 231 typedef struct Column Column; 232 typedef struct Table Table; 233 typedef struct Index Index; 234 typedef struct Instruction Instruction; 235 typedef struct Expr Expr; 236 typedef struct ExprList ExprList; 237 typedef struct Parse Parse; 238 typedef struct Token Token; 239 typedef struct IdList IdList; 240 typedef struct SrcList SrcList; 241 typedef struct WhereInfo WhereInfo; 242 typedef struct WhereLevel WhereLevel; 243 typedef struct Select Select; 244 typedef struct AggExpr AggExpr; 245 typedef struct FuncDef FuncDef; 246 typedef struct Trigger Trigger; 247 typedef struct TriggerStep TriggerStep; 248 typedef struct TriggerStack TriggerStack; 249 typedef struct FKey FKey; 250 typedef struct Db Db; 251 typedef struct AuthContext AuthContext; 252 253 /* 254 ** Each database file to be accessed by the system is an instance 255 ** of the following structure. There are normally two of these structures 256 ** in the sqlite.aDb[] array. aDb[0] is the main database file and 257 ** aDb[1] is the database file used to hold temporary tables. Additional 258 ** databases may be attached. 259 */ 260 struct Db { 261 char *zName; /* Name of this database */ 262 Btree *pBt; /* The B*Tree structure for this database file */ 263 int schema_cookie; /* Database schema version number for this file */ 264 Hash tblHash; /* All tables indexed by name */ 265 Hash idxHash; /* All (named) indices indexed by name */ 266 Hash trigHash; /* All triggers indexed by name */ 267 Hash aFKey; /* Foreign keys indexed by to-table */ 268 u8 inTrans; /* 0: not writable. 1: Transaction. 2: Checkpoint */ 269 u16 flags; /* Flags associated with this database */ 270 void *pAux; /* Auxiliary data. Usually NULL */ 271 void (*xFreeAux)(void*); /* Routine to free pAux */ 272 }; 273 274 /* 275 ** These macros can be used to test, set, or clear bits in the 276 ** Db.flags field. 277 */ 278 #define DbHasProperty(D,I,P) (((D)->aDb[I].flags&(P))==(P)) 279 #define DbHasAnyProperty(D,I,P) (((D)->aDb[I].flags&(P))!=0) 280 #define DbSetProperty(D,I,P) (D)->aDb[I].flags|=(P) 281 #define DbClearProperty(D,I,P) (D)->aDb[I].flags&=~(P) 282 283 /* 284 ** Allowed values for the DB.flags field. 285 ** 286 ** The DB_Locked flag is set when the first OP_Transaction or OP_Checkpoint 287 ** opcode is emitted for a database. This prevents multiple occurances 288 ** of those opcodes for the same database in the same program. Similarly, 289 ** the DB_Cookie flag is set when the OP_VerifyCookie opcode is emitted, 290 ** and prevents duplicate OP_VerifyCookies from taking up space and slowing 291 ** down execution. 292 ** 293 ** The DB_SchemaLoaded flag is set after the database schema has been 294 ** read into internal hash tables. 295 ** 296 ** DB_UnresetViews means that one or more views have column names that 297 ** have been filled out. If the schema changes, these column names might 298 ** changes and so the view will need to be reset. 299 */ 300 #define DB_Locked 0x0001 /* OP_Transaction opcode has been emitted */ 301 #define DB_Cookie 0x0002 /* OP_VerifyCookie opcode has been emiited */ 302 #define DB_SchemaLoaded 0x0004 /* The schema has been loaded */ 303 #define DB_UnresetViews 0x0008 /* Some views have defined column names */ 304 305 306 /* 307 ** Each database is an instance of the following structure. 308 ** 309 ** The sqlite.file_format is initialized by the database file 310 ** and helps determines how the data in the database file is 311 ** represented. This field allows newer versions of the library 312 ** to read and write older databases. The various file formats 313 ** are as follows: 314 ** 315 ** file_format==1 Version 2.1.0. 316 ** file_format==2 Version 2.2.0. Add support for INTEGER PRIMARY KEY. 317 ** file_format==3 Version 2.6.0. Fix empty-string index bug. 318 ** file_format==4 Version 2.7.0. Add support for separate numeric and 319 ** text datatypes. 320 ** 321 ** The sqlite.temp_store determines where temporary database files 322 ** are stored. If 1, then a file is created to hold those tables. If 323 ** 2, then they are held in memory. 0 means use the default value in 324 ** the TEMP_STORE macro. 325 ** 326 ** The sqlite.lastRowid records the last insert rowid generated by an 327 ** insert statement. Inserts on views do not affect its value. Each 328 ** trigger has its own context, so that lastRowid can be updated inside 329 ** triggers as usual. The previous value will be restored once the trigger 330 ** exits. Upon entering a before or instead of trigger, lastRowid is no 331 ** longer (since after version 2.8.12) reset to -1. 332 ** 333 ** The sqlite.nChange does not count changes within triggers and keeps no 334 ** context. It is reset at start of sqlite_exec. 335 ** The sqlite.lsChange represents the number of changes made by the last 336 ** insert, update, or delete statement. It remains constant throughout the 337 ** length of a statement and is then updated by OP_SetCounts. It keeps a 338 ** context stack just like lastRowid so that the count of changes 339 ** within a trigger is not seen outside the trigger. Changes to views do not 340 ** affect the value of lsChange. 341 ** The sqlite.csChange keeps track of the number of current changes (since 342 ** the last statement) and is used to update sqlite_lsChange. 343 */ 344 struct sqlite { 345 int nDb; /* Number of backends currently in use */ 346 Db *aDb; /* All backends */ 347 Db aDbStatic[2]; /* Static space for the 2 default backends */ 348 int flags; /* Miscellanous flags. See below */ 349 u8 file_format; /* What file format version is this database? */ 350 u8 safety_level; /* How aggressive at synching data to disk */ 351 u8 want_to_close; /* Close after all VDBEs are deallocated */ 352 u8 temp_store; /* 1=file, 2=memory, 0=compile-time default */ 353 u8 onError; /* Default conflict algorithm */ 354 int next_cookie; /* Next value of aDb[0].schema_cookie */ 355 int cache_size; /* Number of pages to use in the cache */ 356 int nTable; /* Number of tables in the database */ 357 void *pBusyArg; /* 1st Argument to the busy callback */ 358 int (*xBusyCallback)(void *,const char*,int); /* The busy callback */ 359 void *pCommitArg; /* Argument to xCommitCallback() */ 360 int (*xCommitCallback)(void*);/* Invoked at every commit. */ 361 Hash aFunc; /* All functions that can be in SQL exprs */ 362 int lastRowid; /* ROWID of most recent insert (see above) */ 363 int priorNewRowid; /* Last randomly generated ROWID */ 364 int magic; /* Magic number for detect library misuse */ 365 int nChange; /* Number of rows changed (see above) */ 366 int lsChange; /* Last statement change count (see above) */ 367 int csChange; /* Current statement change count (see above) */ 368 struct sqliteInitInfo { /* Information used during initialization */ 369 int iDb; /* When back is being initialized */ 370 int newTnum; /* Rootpage of table being initialized */ 371 u8 busy; /* TRUE if currently initializing */ 372 } init; 373 struct Vdbe *pVdbe; /* List of active virtual machines */ 374 void (*xTrace)(void*,const char*); /* Trace function */ 375 void *pTraceArg; /* Argument to the trace function */ 376 #ifndef SQLITE_OMIT_AUTHORIZATION 377 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*); 378 /* Access authorization function */ 379 void *pAuthArg; /* 1st argument to the access auth function */ 380 #endif 381 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK 382 int (*xProgress)(void *); /* The progress callback */ 383 void *pProgressArg; /* Argument to the progress callback */ 384 int nProgressOps; /* Number of opcodes for progress callback */ 385 #endif 386 }; 387 388 /* 389 ** Possible values for the sqlite.flags and or Db.flags fields. 390 ** 391 ** On sqlite.flags, the SQLITE_InTrans value means that we have 392 ** executed a BEGIN. On Db.flags, SQLITE_InTrans means a statement 393 ** transaction is active on that particular database file. 394 */ 395 #define SQLITE_VdbeTrace 0x00000001 /* True to trace VDBE execution */ 396 #define SQLITE_Initialized 0x00000002 /* True after initialization */ 397 #define SQLITE_Interrupt 0x00000004 /* Cancel current operation */ 398 #define SQLITE_InTrans 0x00000008 /* True if in a transaction */ 399 #define SQLITE_InternChanges 0x00000010 /* Uncommitted Hash table changes */ 400 #define SQLITE_FullColNames 0x00000020 /* Show full column names on SELECT */ 401 #define SQLITE_ShortColNames 0x00000040 /* Show short columns names */ 402 #define SQLITE_CountRows 0x00000080 /* Count rows changed by INSERT, */ 403 /* DELETE, or UPDATE and return */ 404 /* the count using a callback. */ 405 #define SQLITE_NullCallback 0x00000100 /* Invoke the callback once if the */ 406 /* result set is empty */ 407 #define SQLITE_ReportTypes 0x00000200 /* Include information on datatypes */ 408 /* in 4th argument of callback */ 409 410 /* 411 ** Possible values for the sqlite.magic field. 412 ** The numbers are obtained at random and have no special meaning, other 413 ** than being distinct from one another. 414 */ 415 #define SQLITE_MAGIC_OPEN 0xa029a697 /* Database is open */ 416 #define SQLITE_MAGIC_CLOSED 0x9f3c2d33 /* Database is closed */ 417 #define SQLITE_MAGIC_BUSY 0xf03b7906 /* Database currently in use */ 418 #define SQLITE_MAGIC_ERROR 0xb5357930 /* An SQLITE_MISUSE error occurred */ 419 420 /* 421 ** Each SQL function is defined by an instance of the following 422 ** structure. A pointer to this structure is stored in the sqlite.aFunc 423 ** hash table. When multiple functions have the same name, the hash table 424 ** points to a linked list of these structures. 425 */ 426 struct FuncDef { 427 void (*xFunc)(sqlite_func*,int,const char**); /* Regular function */ 428 void (*xStep)(sqlite_func*,int,const char**); /* Aggregate function step */ 429 void (*xFinalize)(sqlite_func*); /* Aggregate function finializer */ 430 signed char nArg; /* Number of arguments. -1 means unlimited */ 431 signed char dataType; /* Arg that determines datatype. -1=NUMERIC, */ 432 /* -2=TEXT. -3=SQLITE_ARGS */ 433 u8 includeTypes; /* Add datatypes to args of xFunc and xStep */ 434 void *pUserData; /* User data parameter */ 435 FuncDef *pNext; /* Next function with same name */ 436 }; 437 438 /* 439 ** information about each column of an SQL table is held in an instance 440 ** of this structure. 441 */ 442 struct Column { 443 char *zName; /* Name of this column */ 444 char *zDflt; /* Default value of this column */ 445 char *zType; /* Data type for this column */ 446 u8 notNull; /* True if there is a NOT NULL constraint */ 447 u8 isPrimKey; /* True if this column is part of the PRIMARY KEY */ 448 u8 sortOrder; /* Some combination of SQLITE_SO_... values */ 449 u8 dottedName; /* True if zName contains a "." character */ 450 }; 451 452 /* 453 ** The allowed sort orders. 454 ** 455 ** The TEXT and NUM values use bits that do not overlap with DESC and ASC. 456 ** That way the two can be combined into a single number. 457 */ 458 #define SQLITE_SO_UNK 0 /* Use the default collating type. (SCT_NUM) */ 459 #define SQLITE_SO_TEXT 2 /* Sort using memcmp() */ 460 #define SQLITE_SO_NUM 4 /* Sort using sqliteCompare() */ 461 #define SQLITE_SO_TYPEMASK 6 /* Mask to extract the collating sequence */ 462 #define SQLITE_SO_ASC 0 /* Sort in ascending order */ 463 #define SQLITE_SO_DESC 1 /* Sort in descending order */ 464 #define SQLITE_SO_DIRMASK 1 /* Mask to extract the sort direction */ 465 466 /* 467 ** Each SQL table is represented in memory by an instance of the 468 ** following structure. 469 ** 470 ** Table.zName is the name of the table. The case of the original 471 ** CREATE TABLE statement is stored, but case is not significant for 472 ** comparisons. 473 ** 474 ** Table.nCol is the number of columns in this table. Table.aCol is a 475 ** pointer to an array of Column structures, one for each column. 476 ** 477 ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of 478 ** the column that is that key. Otherwise Table.iPKey is negative. Note 479 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to 480 ** be set. An INTEGER PRIMARY KEY is used as the rowid for each row of 481 ** the table. If a table has no INTEGER PRIMARY KEY, then a random rowid 482 ** is generated for each row of the table. Table.hasPrimKey is true if 483 ** the table has any PRIMARY KEY, INTEGER or otherwise. 484 ** 485 ** Table.tnum is the page number for the root BTree page of the table in the 486 ** database file. If Table.iDb is the index of the database table backend 487 ** in sqlite.aDb[]. 0 is for the main database and 1 is for the file that 488 ** holds temporary tables and indices. If Table.isTransient 489 ** is true, then the table is stored in a file that is automatically deleted 490 ** when the VDBE cursor to the table is closed. In this case Table.tnum 491 ** refers VDBE cursor number that holds the table open, not to the root 492 ** page number. Transient tables are used to hold the results of a 493 ** sub-query that appears instead of a real table name in the FROM clause 494 ** of a SELECT statement. 495 */ 496 struct Table { 497 char *zName; /* Name of the table */ 498 int nCol; /* Number of columns in this table */ 499 Column *aCol; /* Information about each column */ 500 int iPKey; /* If not less then 0, use aCol[iPKey] as the primary key */ 501 Index *pIndex; /* List of SQL indexes on this table. */ 502 int tnum; /* Root BTree node for this table (see note above) */ 503 Select *pSelect; /* NULL for tables. Points to definition if a view. */ 504 u8 readOnly; /* True if this table should not be written by the user */ 505 u8 iDb; /* Index into sqlite.aDb[] of the backend for this table */ 506 u8 isTransient; /* True if automatically deleted when VDBE finishes */ 507 u8 hasPrimKey; /* True if there exists a primary key */ 508 u8 keyConf; /* What to do in case of uniqueness conflict on iPKey */ 509 Trigger *pTrigger; /* List of SQL triggers on this table */ 510 FKey *pFKey; /* Linked list of all foreign keys in this table */ 511 }; 512 513 /* 514 ** Each foreign key constraint is an instance of the following structure. 515 ** 516 ** A foreign key is associated with two tables. The "from" table is 517 ** the table that contains the REFERENCES clause that creates the foreign 518 ** key. The "to" table is the table that is named in the REFERENCES clause. 519 ** Consider this example: 520 ** 521 ** CREATE TABLE ex1( 522 ** a INTEGER PRIMARY KEY, 523 ** b INTEGER CONSTRAINT fk1 REFERENCES ex2(x) 524 ** ); 525 ** 526 ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2". 527 ** 528 ** Each REFERENCES clause generates an instance of the following structure 529 ** which is attached to the from-table. The to-table need not exist when 530 ** the from-table is created. The existance of the to-table is not checked 531 ** until an attempt is made to insert data into the from-table. 532 ** 533 ** The sqlite.aFKey hash table stores pointers to this structure 534 ** given the name of a to-table. For each to-table, all foreign keys 535 ** associated with that table are on a linked list using the FKey.pNextTo 536 ** field. 537 */ 538 struct FKey { 539 Table *pFrom; /* The table that constains the REFERENCES clause */ 540 FKey *pNextFrom; /* Next foreign key in pFrom */ 541 char *zTo; /* Name of table that the key points to */ 542 FKey *pNextTo; /* Next foreign key that points to zTo */ 543 int nCol; /* Number of columns in this key */ 544 struct sColMap { /* Mapping of columns in pFrom to columns in zTo */ 545 int iFrom; /* Index of column in pFrom */ 546 char *zCol; /* Name of column in zTo. If 0 use PRIMARY KEY */ 547 } *aCol; /* One entry for each of nCol column s */ 548 u8 isDeferred; /* True if constraint checking is deferred till COMMIT */ 549 u8 updateConf; /* How to resolve conflicts that occur on UPDATE */ 550 u8 deleteConf; /* How to resolve conflicts that occur on DELETE */ 551 u8 insertConf; /* How to resolve conflicts that occur on INSERT */ 552 }; 553 554 /* 555 ** SQLite supports many different ways to resolve a contraint 556 ** error. ROLLBACK processing means that a constraint violation 557 ** causes the operation in process to fail and for the current transaction 558 ** to be rolled back. ABORT processing means the operation in process 559 ** fails and any prior changes from that one operation are backed out, 560 ** but the transaction is not rolled back. FAIL processing means that 561 ** the operation in progress stops and returns an error code. But prior 562 ** changes due to the same operation are not backed out and no rollback 563 ** occurs. IGNORE means that the particular row that caused the constraint 564 ** error is not inserted or updated. Processing continues and no error 565 ** is returned. REPLACE means that preexisting database rows that caused 566 ** a UNIQUE constraint violation are removed so that the new insert or 567 ** update can proceed. Processing continues and no error is reported. 568 ** 569 ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys. 570 ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the 571 ** same as ROLLBACK for DEFERRED keys. SETNULL means that the foreign 572 ** key is set to NULL. CASCADE means that a DELETE or UPDATE of the 573 ** referenced table row is propagated into the row that holds the 574 ** foreign key. 575 ** 576 ** The following symbolic values are used to record which type 577 ** of action to take. 578 */ 579 #define OE_None 0 /* There is no constraint to check */ 580 #define OE_Rollback 1 /* Fail the operation and rollback the transaction */ 581 #define OE_Abort 2 /* Back out changes but do no rollback transaction */ 582 #define OE_Fail 3 /* Stop the operation but leave all prior changes */ 583 #define OE_Ignore 4 /* Ignore the error. Do not do the INSERT or UPDATE */ 584 #define OE_Replace 5 /* Delete existing record, then do INSERT or UPDATE */ 585 586 #define OE_Restrict 6 /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */ 587 #define OE_SetNull 7 /* Set the foreign key value to NULL */ 588 #define OE_SetDflt 8 /* Set the foreign key value to its default */ 589 #define OE_Cascade 9 /* Cascade the changes */ 590 591 #define OE_Default 99 /* Do whatever the default action is */ 592 593 /* 594 ** Each SQL index is represented in memory by an 595 ** instance of the following structure. 596 ** 597 ** The columns of the table that are to be indexed are described 598 ** by the aiColumn[] field of this structure. For example, suppose 599 ** we have the following table and index: 600 ** 601 ** CREATE TABLE Ex1(c1 int, c2 int, c3 text); 602 ** CREATE INDEX Ex2 ON Ex1(c3,c1); 603 ** 604 ** In the Table structure describing Ex1, nCol==3 because there are 605 ** three columns in the table. In the Index structure describing 606 ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed. 607 ** The value of aiColumn is {2, 0}. aiColumn[0]==2 because the 608 ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[]. 609 ** The second column to be indexed (c1) has an index of 0 in 610 ** Ex1.aCol[], hence Ex2.aiColumn[1]==0. 611 ** 612 ** The Index.onError field determines whether or not the indexed columns 613 ** must be unique and what to do if they are not. When Index.onError=OE_None, 614 ** it means this is not a unique index. Otherwise it is a unique index 615 ** and the value of Index.onError indicate the which conflict resolution 616 ** algorithm to employ whenever an attempt is made to insert a non-unique 617 ** element. 618 */ 619 struct Index { 620 char *zName; /* Name of this index */ 621 int nColumn; /* Number of columns in the table used by this index */ 622 int *aiColumn; /* Which columns are used by this index. 1st is 0 */ 623 Table *pTable; /* The SQL table being indexed */ 624 int tnum; /* Page containing root of this index in database file */ 625 u8 onError; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */ 626 u8 autoIndex; /* True if is automatically created (ex: by UNIQUE) */ 627 u8 iDb; /* Index in sqlite.aDb[] of where this index is stored */ 628 Index *pNext; /* The next index associated with the same table */ 629 }; 630 631 /* 632 ** Each token coming out of the lexer is an instance of 633 ** this structure. Tokens are also used as part of an expression. 634 ** 635 ** Note if Token.z==0 then Token.dyn and Token.n are undefined and 636 ** may contain random values. Do not make any assuptions about Token.dyn 637 ** and Token.n when Token.z==0. 638 */ 639 struct Token { 640 const char *z; /* Text of the token. Not NULL-terminated! */ 641 unsigned dyn : 1; /* True for malloced memory, false for static */ 642 unsigned n : 31; /* Number of characters in this token */ 643 }; 644 645 /* 646 ** Each node of an expression in the parse tree is an instance 647 ** of this structure. 648 ** 649 ** Expr.op is the opcode. The integer parser token codes are reused 650 ** as opcodes here. For example, the parser defines TK_GE to be an integer 651 ** code representing the ">=" operator. This same integer code is reused 652 ** to represent the greater-than-or-equal-to operator in the expression 653 ** tree. 654 ** 655 ** Expr.pRight and Expr.pLeft are subexpressions. Expr.pList is a list 656 ** of argument if the expression is a function. 657 ** 658 ** Expr.token is the operator token for this node. For some expressions 659 ** that have subexpressions, Expr.token can be the complete text that gave 660 ** rise to the Expr. In the latter case, the token is marked as being 661 ** a compound token. 662 ** 663 ** An expression of the form ID or ID.ID refers to a column in a table. 664 ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is 665 ** the integer cursor number of a VDBE cursor pointing to that table and 666 ** Expr.iColumn is the column number for the specific column. If the 667 ** expression is used as a result in an aggregate SELECT, then the 668 ** value is also stored in the Expr.iAgg column in the aggregate so that 669 ** it can be accessed after all aggregates are computed. 670 ** 671 ** If the expression is a function, the Expr.iTable is an integer code 672 ** representing which function. If the expression is an unbound variable 673 ** marker (a question mark character '?' in the original SQL) then the 674 ** Expr.iTable holds the index number for that variable. 675 ** 676 ** The Expr.pSelect field points to a SELECT statement. The SELECT might 677 ** be the right operand of an IN operator. Or, if a scalar SELECT appears 678 ** in an expression the opcode is TK_SELECT and Expr.pSelect is the only 679 ** operand. 680 */ 681 struct Expr { 682 u8 op; /* Operation performed by this node */ 683 u8 dataType; /* Either SQLITE_SO_TEXT or SQLITE_SO_NUM */ 684 u8 iDb; /* Database referenced by this expression */ 685 u8 flags; /* Various flags. See below */ 686 Expr *pLeft, *pRight; /* Left and right subnodes */ 687 ExprList *pList; /* A list of expressions used as function arguments 688 ** or in "<expr> IN (<expr-list)" */ 689 Token token; /* An operand token */ 690 Token span; /* Complete text of the expression */ 691 int iTable, iColumn; /* When op==TK_COLUMN, then this expr node means the 692 ** iColumn-th field of the iTable-th table. */ 693 int iAgg; /* When op==TK_COLUMN and pParse->useAgg==TRUE, pull 694 ** result from the iAgg-th element of the aggregator */ 695 Select *pSelect; /* When the expression is a sub-select. Also the 696 ** right side of "<expr> IN (<select>)" */ 697 }; 698 699 /* 700 ** The following are the meanings of bits in the Expr.flags field. 701 */ 702 #define EP_FromJoin 0x0001 /* Originated in ON or USING clause of a join */ 703 704 /* 705 ** These macros can be used to test, set, or clear bits in the 706 ** Expr.flags field. 707 */ 708 #define ExprHasProperty(E,P) (((E)->flags&(P))==(P)) 709 #define ExprHasAnyProperty(E,P) (((E)->flags&(P))!=0) 710 #define ExprSetProperty(E,P) (E)->flags|=(P) 711 #define ExprClearProperty(E,P) (E)->flags&=~(P) 712 713 /* 714 ** A list of expressions. Each expression may optionally have a 715 ** name. An expr/name combination can be used in several ways, such 716 ** as the list of "expr AS ID" fields following a "SELECT" or in the 717 ** list of "ID = expr" items in an UPDATE. A list of expressions can 718 ** also be used as the argument to a function, in which case the a.zName 719 ** field is not used. 720 */ 721 struct ExprList { 722 int nExpr; /* Number of expressions on the list */ 723 int nAlloc; /* Number of entries allocated below */ 724 struct ExprList_item { 725 Expr *pExpr; /* The list of expressions */ 726 char *zName; /* Token associated with this expression */ 727 u8 sortOrder; /* 1 for DESC or 0 for ASC */ 728 u8 isAgg; /* True if this is an aggregate like count(*) */ 729 u8 done; /* A flag to indicate when processing is finished */ 730 } *a; /* One entry for each expression */ 731 }; 732 733 /* 734 ** An instance of this structure can hold a simple list of identifiers, 735 ** such as the list "a,b,c" in the following statements: 736 ** 737 ** INSERT INTO t(a,b,c) VALUES ...; 738 ** CREATE INDEX idx ON t(a,b,c); 739 ** CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...; 740 ** 741 ** The IdList.a.idx field is used when the IdList represents the list of 742 ** column names after a table name in an INSERT statement. In the statement 743 ** 744 ** INSERT INTO t(a,b,c) ... 745 ** 746 ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k. 747 */ 748 struct IdList { 749 int nId; /* Number of identifiers on the list */ 750 int nAlloc; /* Number of entries allocated for a[] below */ 751 struct IdList_item { 752 char *zName; /* Name of the identifier */ 753 int idx; /* Index in some Table.aCol[] of a column named zName */ 754 } *a; 755 }; 756 757 /* 758 ** The following structure describes the FROM clause of a SELECT statement. 759 ** Each table or subquery in the FROM clause is a separate element of 760 ** the SrcList.a[] array. 761 ** 762 ** With the addition of multiple database support, the following structure 763 ** can also be used to describe a particular table such as the table that 764 ** is modified by an INSERT, DELETE, or UPDATE statement. In standard SQL, 765 ** such a table must be a simple name: ID. But in SQLite, the table can 766 ** now be identified by a database name, a dot, then the table name: ID.ID. 767 */ 768 struct SrcList { 769 i16 nSrc; /* Number of tables or subqueries in the FROM clause */ 770 i16 nAlloc; /* Number of entries allocated in a[] below */ 771 struct SrcList_item { 772 char *zDatabase; /* Name of database holding this table */ 773 char *zName; /* Name of the table */ 774 char *zAlias; /* The "B" part of a "A AS B" phrase. zName is the "A" */ 775 Table *pTab; /* An SQL table corresponding to zName */ 776 Select *pSelect; /* A SELECT statement used in place of a table name */ 777 int jointype; /* Type of join between this table and the next */ 778 int iCursor; /* The VDBE cursor number used to access this table */ 779 Expr *pOn; /* The ON clause of a join */ 780 IdList *pUsing; /* The USING clause of a join */ 781 } a[1]; /* One entry for each identifier on the list */ 782 }; 783 784 /* 785 ** Permitted values of the SrcList.a.jointype field 786 */ 787 #define JT_INNER 0x0001 /* Any kind of inner or cross join */ 788 #define JT_NATURAL 0x0002 /* True for a "natural" join */ 789 #define JT_LEFT 0x0004 /* Left outer join */ 790 #define JT_RIGHT 0x0008 /* Right outer join */ 791 #define JT_OUTER 0x0010 /* The "OUTER" keyword is present */ 792 #define JT_ERROR 0x0020 /* unknown or unsupported join type */ 793 794 /* 795 ** For each nested loop in a WHERE clause implementation, the WhereInfo 796 ** structure contains a single instance of this structure. This structure 797 ** is intended to be private the the where.c module and should not be 798 ** access or modified by other modules. 799 */ 800 struct WhereLevel { 801 int iMem; /* Memory cell used by this level */ 802 Index *pIdx; /* Index used */ 803 int iCur; /* Cursor number used for this index */ 804 int score; /* How well this indexed scored */ 805 int brk; /* Jump here to break out of the loop */ 806 int cont; /* Jump here to continue with the next loop cycle */ 807 int op, p1, p2; /* Opcode used to terminate the loop */ 808 int iLeftJoin; /* Memory cell used to implement LEFT OUTER JOIN */ 809 int top; /* First instruction of interior of the loop */ 810 int inOp, inP1, inP2;/* Opcode used to implement an IN operator */ 811 int bRev; /* Do the scan in the reverse direction */ 812 }; 813 814 /* 815 ** The WHERE clause processing routine has two halves. The 816 ** first part does the start of the WHERE loop and the second 817 ** half does the tail of the WHERE loop. An instance of 818 ** this structure is returned by the first half and passed 819 ** into the second half to give some continuity. 820 */ 821 struct WhereInfo { 822 Parse *pParse; 823 SrcList *pTabList; /* List of tables in the join */ 824 int iContinue; /* Jump here to continue with next record */ 825 int iBreak; /* Jump here to break out of the loop */ 826 int nLevel; /* Number of nested loop */ 827 int savedNTab; /* Value of pParse->nTab before WhereBegin() */ 828 int peakNTab; /* Value of pParse->nTab after WhereBegin() */ 829 WhereLevel a[1]; /* Information about each nest loop in the WHERE */ 830 }; 831 832 /* 833 ** An instance of the following structure contains all information 834 ** needed to generate code for a single SELECT statement. 835 ** 836 ** The zSelect field is used when the Select structure must be persistent. 837 ** Normally, the expression tree points to tokens in the original input 838 ** string that encodes the select. But if the Select structure must live 839 ** longer than its input string (for example when it is used to describe 840 ** a VIEW) we have to make a copy of the input string so that the nodes 841 ** of the expression tree will have something to point to. zSelect is used 842 ** to hold that copy. 843 ** 844 ** nLimit is set to -1 if there is no LIMIT clause. nOffset is set to 0. 845 ** If there is a LIMIT clause, the parser sets nLimit to the value of the 846 ** limit and nOffset to the value of the offset (or 0 if there is not 847 ** offset). But later on, nLimit and nOffset become the memory locations 848 ** in the VDBE that record the limit and offset counters. 849 */ 850 struct Select { 851 ExprList *pEList; /* The fields of the result */ 852 u8 op; /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */ 853 u8 isDistinct; /* True if the DISTINCT keyword is present */ 854 SrcList *pSrc; /* The FROM clause */ 855 Expr *pWhere; /* The WHERE clause */ 856 ExprList *pGroupBy; /* The GROUP BY clause */ 857 Expr *pHaving; /* The HAVING clause */ 858 ExprList *pOrderBy; /* The ORDER BY clause */ 859 Select *pPrior; /* Prior select in a compound select statement */ 860 int nLimit, nOffset; /* LIMIT and OFFSET values. -1 means not used */ 861 int iLimit, iOffset; /* Memory registers holding LIMIT & OFFSET counters */ 862 char *zSelect; /* Complete text of the SELECT command */ 863 }; 864 865 /* 866 ** The results of a select can be distributed in several ways. 867 */ 868 #define SRT_Callback 1 /* Invoke a callback with each row of result */ 869 #define SRT_Mem 2 /* Store result in a memory cell */ 870 #define SRT_Set 3 /* Store result as unique keys in a table */ 871 #define SRT_Union 5 /* Store result as keys in a table */ 872 #define SRT_Except 6 /* Remove result from a UNION table */ 873 #define SRT_Table 7 /* Store result as data with a unique key */ 874 #define SRT_TempTable 8 /* Store result in a trasient table */ 875 #define SRT_Discard 9 /* Do not save the results anywhere */ 876 #define SRT_Sorter 10 /* Store results in the sorter */ 877 #define SRT_Subroutine 11 /* Call a subroutine to handle results */ 878 879 /* 880 ** When a SELECT uses aggregate functions (like "count(*)" or "avg(f1)") 881 ** we have to do some additional analysis of expressions. An instance 882 ** of the following structure holds information about a single subexpression 883 ** somewhere in the SELECT statement. An array of these structures holds 884 ** all the information we need to generate code for aggregate 885 ** expressions. 886 ** 887 ** Note that when analyzing a SELECT containing aggregates, both 888 ** non-aggregate field variables and aggregate functions are stored 889 ** in the AggExpr array of the Parser structure. 890 ** 891 ** The pExpr field points to an expression that is part of either the 892 ** field list, the GROUP BY clause, the HAVING clause or the ORDER BY 893 ** clause. The expression will be freed when those clauses are cleaned 894 ** up. Do not try to delete the expression attached to AggExpr.pExpr. 895 ** 896 ** If AggExpr.pExpr==0, that means the expression is "count(*)". 897 */ 898 struct AggExpr { 899 int isAgg; /* if TRUE contains an aggregate function */ 900 Expr *pExpr; /* The expression */ 901 FuncDef *pFunc; /* Information about the aggregate function */ 902 }; 903 904 /* 905 ** An SQL parser context. A copy of this structure is passed through 906 ** the parser and down into all the parser action routine in order to 907 ** carry around information that is global to the entire parse. 908 */ 909 struct Parse { 910 sqlite *db; /* The main database structure */ 911 int rc; /* Return code from execution */ 912 char *zErrMsg; /* An error message */ 913 Token sErrToken; /* The token at which the error occurred */ 914 Token sFirstToken; /* The first token parsed */ 915 Token sLastToken; /* The last token parsed */ 916 const char *zTail; /* All SQL text past the last semicolon parsed */ 917 Table *pNewTable; /* A table being constructed by CREATE TABLE */ 918 Vdbe *pVdbe; /* An engine for executing database bytecode */ 919 u8 colNamesSet; /* TRUE after OP_ColumnName has been issued to pVdbe */ 920 u8 explain; /* True if the EXPLAIN flag is found on the query */ 921 u8 nameClash; /* A permanent table name clashes with temp table name */ 922 u8 useAgg; /* If true, extract field values from the aggregator 923 ** while generating expressions. Normally false */ 924 int nErr; /* Number of errors seen */ 925 int nTab; /* Number of previously allocated VDBE cursors */ 926 int nMem; /* Number of memory cells used so far */ 927 int nSet; /* Number of sets used so far */ 928 int nAgg; /* Number of aggregate expressions */ 929 int nVar; /* Number of '?' variables seen in the SQL so far */ 930 AggExpr *aAgg; /* An array of aggregate expressions */ 931 const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */ 932 Trigger *pNewTrigger; /* Trigger under construct by a CREATE TRIGGER */ 933 TriggerStack *trigStack; /* Trigger actions being coded */ 934 }; 935 936 /* 937 ** An instance of the following structure can be declared on a stack and used 938 ** to save the Parse.zAuthContext value so that it can be restored later. 939 */ 940 struct AuthContext { 941 const char *zAuthContext; /* Put saved Parse.zAuthContext here */ 942 Parse *pParse; /* The Parse structure */ 943 }; 944 945 /* 946 ** Bitfield flags for P2 value in OP_PutIntKey and OP_Delete 947 */ 948 #define OPFLAG_NCHANGE 1 /* Set to update db->nChange */ 949 #define OPFLAG_LASTROWID 2 /* Set to update db->lastRowid */ 950 #define OPFLAG_CSCHANGE 4 /* Set to update db->csChange */ 951 952 /* 953 * Each trigger present in the database schema is stored as an instance of 954 * struct Trigger. 955 * 956 * Pointers to instances of struct Trigger are stored in two ways. 957 * 1. In the "trigHash" hash table (part of the sqlite* that represents the 958 * database). This allows Trigger structures to be retrieved by name. 959 * 2. All triggers associated with a single table form a linked list, using the 960 * pNext member of struct Trigger. A pointer to the first element of the 961 * linked list is stored as the "pTrigger" member of the associated 962 * struct Table. 963 * 964 * The "step_list" member points to the first element of a linked list 965 * containing the SQL statements specified as the trigger program. 966 */ 967 struct Trigger { 968 char *name; /* The name of the trigger */ 969 char *table; /* The table or view to which the trigger applies */ 970 u8 iDb; /* Database containing this trigger */ 971 u8 iTabDb; /* Database containing Trigger.table */ 972 u8 op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT */ 973 u8 tr_tm; /* One of TK_BEFORE, TK_AFTER */ 974 Expr *pWhen; /* The WHEN clause of the expresion (may be NULL) */ 975 IdList *pColumns; /* If this is an UPDATE OF <column-list> trigger, 976 the <column-list> is stored here */ 977 int foreach; /* One of TK_ROW or TK_STATEMENT */ 978 Token nameToken; /* Token containing zName. Use during parsing only */ 979 980 TriggerStep *step_list; /* Link list of trigger program steps */ 981 Trigger *pNext; /* Next trigger associated with the table */ 982 }; 983 984 /* 985 * An instance of struct TriggerStep is used to store a single SQL statement 986 * that is a part of a trigger-program. 987 * 988 * Instances of struct TriggerStep are stored in a singly linked list (linked 989 * using the "pNext" member) referenced by the "step_list" member of the 990 * associated struct Trigger instance. The first element of the linked list is 991 * the first step of the trigger-program. 992 * 993 * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or 994 * "SELECT" statement. The meanings of the other members is determined by the 995 * value of "op" as follows: 996 * 997 * (op == TK_INSERT) 998 * orconf -> stores the ON CONFLICT algorithm 999 * pSelect -> If this is an INSERT INTO ... SELECT ... statement, then 1000 * this stores a pointer to the SELECT statement. Otherwise NULL. 1001 * target -> A token holding the name of the table to insert into. 1002 * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then 1003 * this stores values to be inserted. Otherwise NULL. 1004 * pIdList -> If this is an INSERT INTO ... (<column-names>) VALUES ... 1005 * statement, then this stores the column-names to be 1006 * inserted into. 1007 * 1008 * (op == TK_DELETE) 1009 * target -> A token holding the name of the table to delete from. 1010 * pWhere -> The WHERE clause of the DELETE statement if one is specified. 1011 * Otherwise NULL. 1012 * 1013 * (op == TK_UPDATE) 1014 * target -> A token holding the name of the table to update rows of. 1015 * pWhere -> The WHERE clause of the UPDATE statement if one is specified. 1016 * Otherwise NULL. 1017 * pExprList -> A list of the columns to update and the expressions to update 1018 * them to. See sqliteUpdate() documentation of "pChanges" 1019 * argument. 1020 * 1021 */ 1022 struct TriggerStep { 1023 int op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */ 1024 int orconf; /* OE_Rollback etc. */ 1025 Trigger *pTrig; /* The trigger that this step is a part of */ 1026 1027 Select *pSelect; /* Valid for SELECT and sometimes 1028 INSERT steps (when pExprList == 0) */ 1029 Token target; /* Valid for DELETE, UPDATE, INSERT steps */ 1030 Expr *pWhere; /* Valid for DELETE, UPDATE steps */ 1031 ExprList *pExprList; /* Valid for UPDATE statements and sometimes 1032 INSERT steps (when pSelect == 0) */ 1033 IdList *pIdList; /* Valid for INSERT statements only */ 1034 1035 TriggerStep * pNext; /* Next in the link-list */ 1036 }; 1037 1038 /* 1039 * An instance of struct TriggerStack stores information required during code 1040 * generation of a single trigger program. While the trigger program is being 1041 * coded, its associated TriggerStack instance is pointed to by the 1042 * "pTriggerStack" member of the Parse structure. 1043 * 1044 * The pTab member points to the table that triggers are being coded on. The 1045 * newIdx member contains the index of the vdbe cursor that points at the temp 1046 * table that stores the new.* references. If new.* references are not valid 1047 * for the trigger being coded (for example an ON DELETE trigger), then newIdx 1048 * is set to -1. The oldIdx member is analogous to newIdx, for old.* references. 1049 * 1050 * The ON CONFLICT policy to be used for the trigger program steps is stored 1051 * as the orconf member. If this is OE_Default, then the ON CONFLICT clause 1052 * specified for individual triggers steps is used. 1053 * 1054 * struct TriggerStack has a "pNext" member, to allow linked lists to be 1055 * constructed. When coding nested triggers (triggers fired by other triggers) 1056 * each nested trigger stores its parent trigger's TriggerStack as the "pNext" 1057 * pointer. Once the nested trigger has been coded, the pNext value is restored 1058 * to the pTriggerStack member of the Parse stucture and coding of the parent 1059 * trigger continues. 1060 * 1061 * Before a nested trigger is coded, the linked list pointed to by the 1062 * pTriggerStack is scanned to ensure that the trigger is not about to be coded 1063 * recursively. If this condition is detected, the nested trigger is not coded. 1064 */ 1065 struct TriggerStack { 1066 Table *pTab; /* Table that triggers are currently being coded on */ 1067 int newIdx; /* Index of vdbe cursor to "new" temp table */ 1068 int oldIdx; /* Index of vdbe cursor to "old" temp table */ 1069 int orconf; /* Current orconf policy */ 1070 int ignoreJump; /* where to jump to for a RAISE(IGNORE) */ 1071 Trigger *pTrigger; /* The trigger currently being coded */ 1072 TriggerStack *pNext; /* Next trigger down on the trigger stack */ 1073 }; 1074 1075 /* 1076 ** The following structure contains information used by the sqliteFix... 1077 ** routines as they walk the parse tree to make database references 1078 ** explicit. 1079 */ 1080 typedef struct DbFixer DbFixer; 1081 struct DbFixer { 1082 Parse *pParse; /* The parsing context. Error messages written here */ 1083 const char *zDb; /* Make sure all objects are contained in this database */ 1084 const char *zType; /* Type of the container - used for error messages */ 1085 const Token *pName; /* Name of the container - used for error messages */ 1086 }; 1087 1088 /* 1089 * This global flag is set for performance testing of triggers. When it is set 1090 * SQLite will perform the overhead of building new and old trigger references 1091 * even when no triggers exist 1092 */ 1093 extern int always_code_trigger_setup; 1094 1095 /* 1096 ** Internal function prototypes 1097 */ 1098 int sqliteStrICmp(const char *, const char *); 1099 int sqliteStrNICmp(const char *, const char *, int); 1100 int sqliteHashNoCase(const char *, int); 1101 int sqliteIsNumber(const char*); 1102 int sqliteCompare(const char *, const char *); 1103 int sqliteSortCompare(const char *, const char *); 1104 void sqliteRealToSortable(double r, char *); 1105 #ifdef MEMORY_DEBUG 1106 void *sqliteMalloc_(int,int,char*,int); 1107 void sqliteFree_(void*,char*,int); 1108 void *sqliteRealloc_(void*,int,char*,int); 1109 char *sqliteStrDup_(const char*,char*,int); 1110 char *sqliteStrNDup_(const char*, int,char*,int); 1111 void sqliteCheckMemory(void*,int); 1112 #else 1113 void *sqliteMalloc(int); 1114 void *sqliteMallocRaw(int); 1115 void sqliteFree(void*); 1116 void *sqliteRealloc(void*,int); 1117 char *sqliteStrDup(const char*); 1118 char *sqliteStrNDup(const char*, int); 1119 # define sqliteCheckMemory(a,b) 1120 #endif 1121 char *sqliteMPrintf(const char*, ...); 1122 char *sqliteVMPrintf(const char*, va_list); 1123 void sqliteSetString(char **, const char *, ...); 1124 void sqliteSetNString(char **, ...); 1125 void sqliteErrorMsg(Parse*, const char*, ...); 1126 void sqliteDequote(char*); 1127 int sqliteKeywordCode(const char*, int); 1128 int sqliteRunParser(Parse*, const char*, char **); 1129 void sqliteExec(Parse*); 1130 Expr *sqliteExpr(int, Expr*, Expr*, Token*); 1131 void sqliteExprSpan(Expr*,Token*,Token*); 1132 Expr *sqliteExprFunction(ExprList*, Token*); 1133 void sqliteExprDelete(Expr*); 1134 ExprList *sqliteExprListAppend(ExprList*,Expr*,Token*); 1135 void sqliteExprListDelete(ExprList*); 1136 int sqliteInit(sqlite*, char**); 1137 void sqlitePragma(Parse*,Token*,Token*,int); 1138 void sqliteResetInternalSchema(sqlite*, int); 1139 void sqliteBeginParse(Parse*,int); 1140 void sqliteRollbackInternalChanges(sqlite*); 1141 void sqliteCommitInternalChanges(sqlite*); 1142 Table *sqliteResultSetOfSelect(Parse*,char*,Select*); 1143 void sqliteOpenMasterTable(Vdbe *v, int); 1144 void sqliteStartTable(Parse*,Token*,Token*,int,int); 1145 void sqliteAddColumn(Parse*,Token*); 1146 void sqliteAddNotNull(Parse*, int); 1147 void sqliteAddPrimaryKey(Parse*, IdList*, int); 1148 void sqliteAddColumnType(Parse*,Token*,Token*); 1149 void sqliteAddDefaultValue(Parse*,Token*,int); 1150 int sqliteCollateType(const char*, int); 1151 void sqliteAddCollateType(Parse*, int); 1152 void sqliteEndTable(Parse*,Token*,Select*); 1153 void sqliteCreateView(Parse*,Token*,Token*,Select*,int); 1154 int sqliteViewGetColumnNames(Parse*,Table*); 1155 void sqliteDropTable(Parse*, Token*, int); 1156 void sqliteDeleteTable(sqlite*, Table*); 1157 void sqliteInsert(Parse*, SrcList*, ExprList*, Select*, IdList*, int); 1158 IdList *sqliteIdListAppend(IdList*, Token*); 1159 int sqliteIdListIndex(IdList*,const char*); 1160 SrcList *sqliteSrcListAppend(SrcList*, Token*, Token*); 1161 void sqliteSrcListAddAlias(SrcList*, Token*); 1162 void sqliteSrcListAssignCursors(Parse*, SrcList*); 1163 void sqliteIdListDelete(IdList*); 1164 void sqliteSrcListDelete(SrcList*); 1165 void sqliteCreateIndex(Parse*,Token*,SrcList*,IdList*,int,Token*,Token*); 1166 void sqliteDropIndex(Parse*, SrcList*); 1167 void sqliteAddKeyType(Vdbe*, ExprList*); 1168 void sqliteAddIdxKeyType(Vdbe*, Index*); 1169 int sqliteSelect(Parse*, Select*, int, int, Select*, int, int*); 1170 Select *sqliteSelectNew(ExprList*,SrcList*,Expr*,ExprList*,Expr*,ExprList*, 1171 int,int,int); 1172 void sqliteSelectDelete(Select*); 1173 void sqliteSelectUnbind(Select*); 1174 Table *sqliteSrcListLookup(Parse*, SrcList*); 1175 int sqliteIsReadOnly(Parse*, Table*, int); 1176 void sqliteDeleteFrom(Parse*, SrcList*, Expr*); 1177 void sqliteUpdate(Parse*, SrcList*, ExprList*, Expr*, int); 1178 WhereInfo *sqliteWhereBegin(Parse*, SrcList*, Expr*, int, ExprList**); 1179 void sqliteWhereEnd(WhereInfo*); 1180 void sqliteExprCode(Parse*, Expr*); 1181 int sqliteExprCodeExprList(Parse*, ExprList*, int); 1182 void sqliteExprIfTrue(Parse*, Expr*, int, int); 1183 void sqliteExprIfFalse(Parse*, Expr*, int, int); 1184 Table *sqliteFindTable(sqlite*,const char*, const char*); 1185 Table *sqliteLocateTable(Parse*,const char*, const char*); 1186 Index *sqliteFindIndex(sqlite*,const char*, const char*); 1187 void sqliteUnlinkAndDeleteIndex(sqlite*,Index*); 1188 void sqliteCopy(Parse*, SrcList*, Token*, Token*, int); 1189 void sqliteVacuum(Parse*, Token*); 1190 int sqliteRunVacuum(char**, sqlite*); 1191 int sqliteGlobCompare(const unsigned char*,const unsigned char*); 1192 int sqliteLikeCompare(const unsigned char*,const unsigned char*); 1193 char *sqliteTableNameFromToken(Token*); 1194 int sqliteExprCheck(Parse*, Expr*, int, int*); 1195 int sqliteExprType(Expr*); 1196 int sqliteExprCompare(Expr*, Expr*); 1197 int sqliteFuncId(Token*); 1198 int sqliteExprResolveIds(Parse*, SrcList*, ExprList*, Expr*); 1199 int sqliteExprAnalyzeAggregates(Parse*, Expr*); 1200 Vdbe *sqliteGetVdbe(Parse*); 1201 void sqliteRandomness(int, void*); 1202 void sqliteRollbackAll(sqlite*); 1203 void sqliteCodeVerifySchema(Parse*, int); 1204 void sqliteBeginTransaction(Parse*, int); 1205 void sqliteCommitTransaction(Parse*); 1206 void sqliteRollbackTransaction(Parse*); 1207 int sqliteExprIsConstant(Expr*); 1208 int sqliteExprIsInteger(Expr*, int*); 1209 int sqliteIsRowid(const char*); 1210 void sqliteGenerateRowDelete(sqlite*, Vdbe*, Table*, int, int); 1211 void sqliteGenerateRowIndexDelete(sqlite*, Vdbe*, Table*, int, char*); 1212 void sqliteGenerateConstraintChecks(Parse*,Table*,int,char*,int,int,int,int); 1213 void sqliteCompleteInsertion(Parse*, Table*, int, char*, int, int, int); 1214 int sqliteOpenTableAndIndices(Parse*, Table*, int); 1215 void sqliteBeginWriteOperation(Parse*, int, int); 1216 void sqliteEndWriteOperation(Parse*); 1217 Expr *sqliteExprDup(Expr*); 1218 void sqliteTokenCopy(Token*, Token*); 1219 ExprList *sqliteExprListDup(ExprList*); 1220 SrcList *sqliteSrcListDup(SrcList*); 1221 IdList *sqliteIdListDup(IdList*); 1222 Select *sqliteSelectDup(Select*); 1223 FuncDef *sqliteFindFunction(sqlite*,const char*,int,int,int); 1224 void sqliteRegisterBuiltinFunctions(sqlite*); 1225 void sqliteRegisterDateTimeFunctions(sqlite*); 1226 int sqliteSafetyOn(sqlite*); 1227 int sqliteSafetyOff(sqlite*); 1228 int sqliteSafetyCheck(sqlite*); 1229 void sqliteChangeCookie(sqlite*, Vdbe*); 1230 void sqliteBeginTrigger(Parse*, Token*,int,int,IdList*,SrcList*,int,Expr*,int); 1231 void sqliteFinishTrigger(Parse*, TriggerStep*, Token*); 1232 void sqliteDropTrigger(Parse*, SrcList*); 1233 void sqliteDropTriggerPtr(Parse*, Trigger*, int); 1234 int sqliteTriggersExist(Parse* , Trigger* , int , int , int, ExprList*); 1235 int sqliteCodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int, 1236 int, int); 1237 void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*); 1238 void sqliteDeleteTriggerStep(TriggerStep*); 1239 TriggerStep *sqliteTriggerSelectStep(Select*); 1240 TriggerStep *sqliteTriggerInsertStep(Token*, IdList*, ExprList*, Select*, int); 1241 TriggerStep *sqliteTriggerUpdateStep(Token*, ExprList*, Expr*, int); 1242 TriggerStep *sqliteTriggerDeleteStep(Token*, Expr*); 1243 void sqliteDeleteTrigger(Trigger*); 1244 int sqliteJoinType(Parse*, Token*, Token*, Token*); 1245 void sqliteCreateForeignKey(Parse*, IdList*, Token*, IdList*, int); 1246 void sqliteDeferForeignKey(Parse*, int); 1247 #ifndef SQLITE_OMIT_AUTHORIZATION 1248 void sqliteAuthRead(Parse*,Expr*,SrcList*); 1249 int sqliteAuthCheck(Parse*,int, const char*, const char*, const char*); 1250 void sqliteAuthContextPush(Parse*, AuthContext*, const char*); 1251 void sqliteAuthContextPop(AuthContext*); 1252 #else 1253 # define sqliteAuthRead(a,b,c) 1254 # define sqliteAuthCheck(a,b,c,d,e) SQLITE_OK 1255 # define sqliteAuthContextPush(a,b,c) 1256 # define sqliteAuthContextPop(a) ((void)(a)) 1257 #endif 1258 void sqliteAttach(Parse*, Token*, Token*, Token*); 1259 void sqliteDetach(Parse*, Token*); 1260 int sqliteBtreeFactory(const sqlite *db, const char *zFilename, 1261 int mode, int nPg, Btree **ppBtree); 1262 int sqliteFixInit(DbFixer*, Parse*, int, const char*, const Token*); 1263 int sqliteFixSrcList(DbFixer*, SrcList*); 1264 int sqliteFixSelect(DbFixer*, Select*); 1265 int sqliteFixExpr(DbFixer*, Expr*); 1266 int sqliteFixExprList(DbFixer*, ExprList*); 1267 int sqliteFixTriggerStep(DbFixer*, TriggerStep*); 1268 double sqliteAtoF(const char *z, const char **); 1269 char *sqlite_snprintf(int,char*,const char*,...); 1270 int sqliteFitsIn32Bits(const char *); 1271