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 ** An tokenizer for SQL 13 ** 14 ** This file contains C code that splits an SQL input string up into 15 ** individual tokens and sends those tokens one-by-one over to the 16 ** parser for analysis. 17 */ 18 #include "sqliteInt.h" 19 #include <stdlib.h> 20 21 /* 22 ** The charMap() macro maps alphabetic characters into their 23 ** lower-case ASCII equivalent. On ASCII machines, this is just 24 ** an upper-to-lower case map. On EBCDIC machines we also need 25 ** to adjust the encoding. Only alphabetic characters and underscores 26 ** need to be translated. 27 */ 28 #ifdef SQLITE_ASCII 29 # define charMap(X) sqlite3UpperToLower[(unsigned char)X] 30 #endif 31 #ifdef SQLITE_EBCDIC 32 # define charMap(X) ebcdicToAscii[(unsigned char)X] 33 const unsigned char ebcdicToAscii[] = { 34 /* 0 1 2 3 4 5 6 7 8 9 A B C D E F */ 35 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x */ 36 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 1x */ 37 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 2x */ 38 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 3x */ 39 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 4x */ 40 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 5x */ 41 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 95, 0, 0, /* 6x */ 42 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 7x */ 43 0, 97, 98, 99,100,101,102,103,104,105, 0, 0, 0, 0, 0, 0, /* 8x */ 44 0,106,107,108,109,110,111,112,113,114, 0, 0, 0, 0, 0, 0, /* 9x */ 45 0, 0,115,116,117,118,119,120,121,122, 0, 0, 0, 0, 0, 0, /* Ax */ 46 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* Bx */ 47 0, 97, 98, 99,100,101,102,103,104,105, 0, 0, 0, 0, 0, 0, /* Cx */ 48 0,106,107,108,109,110,111,112,113,114, 0, 0, 0, 0, 0, 0, /* Dx */ 49 0, 0,115,116,117,118,119,120,121,122, 0, 0, 0, 0, 0, 0, /* Ex */ 50 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* Fx */ 51 }; 52 #endif 53 54 /* 55 ** The sqlite3KeywordCode function looks up an identifier to determine if 56 ** it is a keyword. If it is a keyword, the token code of that keyword is 57 ** returned. If the input is not a keyword, TK_ID is returned. 58 ** 59 ** The implementation of this routine was generated by a program, 60 ** mkkeywordhash.h, located in the tool subdirectory of the distribution. 61 ** The output of the mkkeywordhash.c program is written into a file 62 ** named keywordhash.h and then included into this source file by 63 ** the #include below. 64 */ 65 #include "keywordhash.h" 66 67 68 /* 69 ** If X is a character that can be used in an identifier then 70 ** IdChar(X) will be true. Otherwise it is false. 71 ** 72 ** For ASCII, any character with the high-order bit set is 73 ** allowed in an identifier. For 7-bit characters, 74 ** sqlite3IsIdChar[X] must be 1. 75 ** 76 ** For EBCDIC, the rules are more complex but have the same 77 ** end result. 78 ** 79 ** Ticket #1066. the SQL standard does not allow '$' in the 80 ** middle of identfiers. But many SQL implementations do. 81 ** SQLite will allow '$' in identifiers for compatibility. 82 ** But the feature is undocumented. 83 */ 84 #ifdef SQLITE_ASCII 85 #define IdChar(C) ((sqlite3CtypeMap[(unsigned char)C]&0x46)!=0) 86 #endif 87 #ifdef SQLITE_EBCDIC 88 const char sqlite3IsEbcdicIdChar[] = { 89 /* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */ 90 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, /* 4x */ 91 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, /* 5x */ 92 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, /* 6x */ 93 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, /* 7x */ 94 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, /* 8x */ 95 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, /* 9x */ 96 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, /* Ax */ 97 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* Bx */ 98 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, /* Cx */ 99 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, /* Dx */ 100 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, /* Ex */ 101 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, /* Fx */ 102 }; 103 #define IdChar(C) (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40])) 104 #endif 105 106 107 /* 108 ** Return the length of the token that begins at z[0]. 109 ** Store the token type in *tokenType before returning. 110 */ 111 int sqlite3GetToken(const unsigned char *z, int *tokenType){ 112 int i, c; 113 switch( *z ){ 114 case ' ': case '\t': case '\n': case '\f': case '\r': { 115 testcase( z[0]==' ' ); 116 testcase( z[0]=='\t' ); 117 testcase( z[0]=='\n' ); 118 testcase( z[0]=='\f' ); 119 testcase( z[0]=='\r' ); 120 for(i=1; sqlite3Isspace(z[i]); i++){} 121 *tokenType = TK_SPACE; 122 return i; 123 } 124 case '-': { 125 if( z[1]=='-' ){ 126 /* IMP: R-50417-27976 -- syntax diagram for comments */ 127 for(i=2; (c=z[i])!=0 && c!='\n'; i++){} 128 *tokenType = TK_SPACE; /* IMP: R-22934-25134 */ 129 return i; 130 } 131 *tokenType = TK_MINUS; 132 return 1; 133 } 134 case '(': { 135 *tokenType = TK_LP; 136 return 1; 137 } 138 case ')': { 139 *tokenType = TK_RP; 140 return 1; 141 } 142 case ';': { 143 *tokenType = TK_SEMI; 144 return 1; 145 } 146 case '+': { 147 *tokenType = TK_PLUS; 148 return 1; 149 } 150 case '*': { 151 *tokenType = TK_STAR; 152 return 1; 153 } 154 case '/': { 155 if( z[1]!='*' || z[2]==0 ){ 156 *tokenType = TK_SLASH; 157 return 1; 158 } 159 /* IMP: R-50417-27976 -- syntax diagram for comments */ 160 for(i=3, c=z[2]; (c!='*' || z[i]!='/') && (c=z[i])!=0; i++){} 161 if( c ) i++; 162 *tokenType = TK_SPACE; /* IMP: R-22934-25134 */ 163 return i; 164 } 165 case '%': { 166 *tokenType = TK_REM; 167 return 1; 168 } 169 case '=': { 170 *tokenType = TK_EQ; 171 return 1 + (z[1]=='='); 172 } 173 case '<': { 174 if( (c=z[1])=='=' ){ 175 *tokenType = TK_LE; 176 return 2; 177 }else if( c=='>' ){ 178 *tokenType = TK_NE; 179 return 2; 180 }else if( c=='<' ){ 181 *tokenType = TK_LSHIFT; 182 return 2; 183 }else{ 184 *tokenType = TK_LT; 185 return 1; 186 } 187 } 188 case '>': { 189 if( (c=z[1])=='=' ){ 190 *tokenType = TK_GE; 191 return 2; 192 }else if( c=='>' ){ 193 *tokenType = TK_RSHIFT; 194 return 2; 195 }else{ 196 *tokenType = TK_GT; 197 return 1; 198 } 199 } 200 case '!': { 201 if( z[1]!='=' ){ 202 *tokenType = TK_ILLEGAL; 203 return 2; 204 }else{ 205 *tokenType = TK_NE; 206 return 2; 207 } 208 } 209 case '|': { 210 if( z[1]!='|' ){ 211 *tokenType = TK_BITOR; 212 return 1; 213 }else{ 214 *tokenType = TK_CONCAT; 215 return 2; 216 } 217 } 218 case ',': { 219 *tokenType = TK_COMMA; 220 return 1; 221 } 222 case '&': { 223 *tokenType = TK_BITAND; 224 return 1; 225 } 226 case '~': { 227 *tokenType = TK_BITNOT; 228 return 1; 229 } 230 case '`': 231 case '\'': 232 case '"': { 233 int delim = z[0]; 234 testcase( delim=='`' ); 235 testcase( delim=='\'' ); 236 testcase( delim=='"' ); 237 for(i=1; (c=z[i])!=0; i++){ 238 if( c==delim ){ 239 if( z[i+1]==delim ){ 240 i++; 241 }else{ 242 break; 243 } 244 } 245 } 246 if( c=='\'' ){ 247 *tokenType = TK_STRING; 248 return i+1; 249 }else if( c!=0 ){ 250 *tokenType = TK_ID; 251 return i+1; 252 }else{ 253 *tokenType = TK_ILLEGAL; 254 return i; 255 } 256 } 257 case '.': { 258 #ifndef SQLITE_OMIT_FLOATING_POINT 259 if( !sqlite3Isdigit(z[1]) ) 260 #endif 261 { 262 *tokenType = TK_DOT; 263 return 1; 264 } 265 /* If the next character is a digit, this is a floating point 266 ** number that begins with ".". Fall thru into the next case */ 267 } 268 case '0': case '1': case '2': case '3': case '4': 269 case '5': case '6': case '7': case '8': case '9': { 270 testcase( z[0]=='0' ); testcase( z[0]=='1' ); testcase( z[0]=='2' ); 271 testcase( z[0]=='3' ); testcase( z[0]=='4' ); testcase( z[0]=='5' ); 272 testcase( z[0]=='6' ); testcase( z[0]=='7' ); testcase( z[0]=='8' ); 273 testcase( z[0]=='9' ); 274 *tokenType = TK_INTEGER; 275 for(i=0; sqlite3Isdigit(z[i]); i++){} 276 #ifndef SQLITE_OMIT_FLOATING_POINT 277 if( z[i]=='.' ){ 278 i++; 279 while( sqlite3Isdigit(z[i]) ){ i++; } 280 *tokenType = TK_FLOAT; 281 } 282 if( (z[i]=='e' || z[i]=='E') && 283 ( sqlite3Isdigit(z[i+1]) 284 || ((z[i+1]=='+' || z[i+1]=='-') && sqlite3Isdigit(z[i+2])) 285 ) 286 ){ 287 i += 2; 288 while( sqlite3Isdigit(z[i]) ){ i++; } 289 *tokenType = TK_FLOAT; 290 } 291 #endif 292 while( IdChar(z[i]) ){ 293 *tokenType = TK_ILLEGAL; 294 i++; 295 } 296 return i; 297 } 298 case '[': { 299 for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){} 300 *tokenType = c==']' ? TK_ID : TK_ILLEGAL; 301 return i; 302 } 303 case '?': { 304 *tokenType = TK_VARIABLE; 305 for(i=1; sqlite3Isdigit(z[i]); i++){} 306 return i; 307 } 308 case '#': { 309 for(i=1; sqlite3Isdigit(z[i]); i++){} 310 if( i>1 ){ 311 /* Parameters of the form #NNN (where NNN is a number) are used 312 ** internally by sqlite3NestedParse. */ 313 *tokenType = TK_REGISTER; 314 return i; 315 } 316 /* Fall through into the next case if the '#' is not followed by 317 ** a digit. Try to match #AAAA where AAAA is a parameter name. */ 318 } 319 #ifndef SQLITE_OMIT_TCL_VARIABLE 320 case '$': 321 #endif 322 case '@': /* For compatibility with MS SQL Server */ 323 case ':': { 324 int n = 0; 325 testcase( z[0]=='$' ); testcase( z[0]=='@' ); testcase( z[0]==':' ); 326 *tokenType = TK_VARIABLE; 327 for(i=1; (c=z[i])!=0; i++){ 328 if( IdChar(c) ){ 329 n++; 330 #ifndef SQLITE_OMIT_TCL_VARIABLE 331 }else if( c=='(' && n>0 ){ 332 do{ 333 i++; 334 }while( (c=z[i])!=0 && !sqlite3Isspace(c) && c!=')' ); 335 if( c==')' ){ 336 i++; 337 }else{ 338 *tokenType = TK_ILLEGAL; 339 } 340 break; 341 }else if( c==':' && z[i+1]==':' ){ 342 i++; 343 #endif 344 }else{ 345 break; 346 } 347 } 348 if( n==0 ) *tokenType = TK_ILLEGAL; 349 return i; 350 } 351 #ifndef SQLITE_OMIT_BLOB_LITERAL 352 case 'x': case 'X': { 353 testcase( z[0]=='x' ); testcase( z[0]=='X' ); 354 if( z[1]=='\'' ){ 355 *tokenType = TK_BLOB; 356 for(i=2; sqlite3Isxdigit(z[i]); i++){} 357 if( z[i]!='\'' || i%2 ){ 358 *tokenType = TK_ILLEGAL; 359 while( z[i] && z[i]!='\'' ){ i++; } 360 } 361 if( z[i] ) i++; 362 return i; 363 } 364 /* Otherwise fall through to the next case */ 365 } 366 #endif 367 default: { 368 if( !IdChar(*z) ){ 369 break; 370 } 371 for(i=1; IdChar(z[i]); i++){} 372 *tokenType = keywordCode((char*)z, i); 373 return i; 374 } 375 } 376 *tokenType = TK_ILLEGAL; 377 return 1; 378 } 379 380 /* 381 ** Run the parser on the given SQL string. The parser structure is 382 ** passed in. An SQLITE_ status code is returned. If an error occurs 383 ** then an and attempt is made to write an error message into 384 ** memory obtained from sqlite3_malloc() and to make *pzErrMsg point to that 385 ** error message. 386 */ 387 int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){ 388 int nErr = 0; /* Number of errors encountered */ 389 int i; /* Loop counter */ 390 void *pEngine; /* The LEMON-generated LALR(1) parser */ 391 int tokenType; /* type of the next token */ 392 int lastTokenParsed = -1; /* type of the previous token */ 393 u8 enableLookaside; /* Saved value of db->lookaside.bEnabled */ 394 sqlite3 *db = pParse->db; /* The database connection */ 395 int mxSqlLen; /* Max length of an SQL string */ 396 397 398 mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH]; 399 if( db->activeVdbeCnt==0 ){ 400 db->u1.isInterrupted = 0; 401 } 402 pParse->rc = SQLITE_OK; 403 pParse->zTail = zSql; 404 i = 0; 405 assert( pzErrMsg!=0 ); 406 pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3Malloc); 407 if( pEngine==0 ){ 408 db->mallocFailed = 1; 409 return SQLITE_NOMEM; 410 } 411 assert( pParse->pNewTable==0 ); 412 assert( pParse->pNewTrigger==0 ); 413 assert( pParse->nVar==0 ); 414 assert( pParse->nzVar==0 ); 415 assert( pParse->azVar==0 ); 416 enableLookaside = db->lookaside.bEnabled; 417 if( db->lookaside.pStart ) db->lookaside.bEnabled = 1; 418 while( !db->mallocFailed && zSql[i]!=0 ){ 419 assert( i>=0 ); 420 pParse->sLastToken.z = &zSql[i]; 421 pParse->sLastToken.n = sqlite3GetToken((unsigned char*)&zSql[i],&tokenType); 422 i += pParse->sLastToken.n; 423 if( i>mxSqlLen ){ 424 pParse->rc = SQLITE_TOOBIG; 425 break; 426 } 427 switch( tokenType ){ 428 case TK_SPACE: { 429 if( db->u1.isInterrupted ){ 430 sqlite3ErrorMsg(pParse, "interrupt"); 431 pParse->rc = SQLITE_INTERRUPT; 432 goto abort_parse; 433 } 434 break; 435 } 436 case TK_ILLEGAL: { 437 sqlite3DbFree(db, *pzErrMsg); 438 *pzErrMsg = sqlite3MPrintf(db, "unrecognized token: \"%T\"", 439 &pParse->sLastToken); 440 nErr++; 441 goto abort_parse; 442 } 443 case TK_SEMI: { 444 pParse->zTail = &zSql[i]; 445 /* Fall thru into the default case */ 446 } 447 default: { 448 sqlite3Parser(pEngine, tokenType, pParse->sLastToken, pParse); 449 lastTokenParsed = tokenType; 450 if( pParse->rc!=SQLITE_OK ){ 451 goto abort_parse; 452 } 453 break; 454 } 455 } 456 } 457 abort_parse: 458 if( zSql[i]==0 && nErr==0 && pParse->rc==SQLITE_OK ){ 459 if( lastTokenParsed!=TK_SEMI ){ 460 sqlite3Parser(pEngine, TK_SEMI, pParse->sLastToken, pParse); 461 pParse->zTail = &zSql[i]; 462 } 463 sqlite3Parser(pEngine, 0, pParse->sLastToken, pParse); 464 } 465 #ifdef YYTRACKMAXSTACKDEPTH 466 sqlite3StatusSet(SQLITE_STATUS_PARSER_STACK, 467 sqlite3ParserStackPeak(pEngine) 468 ); 469 #endif /* YYDEBUG */ 470 sqlite3ParserFree(pEngine, sqlite3_free); 471 db->lookaside.bEnabled = enableLookaside; 472 if( db->mallocFailed ){ 473 pParse->rc = SQLITE_NOMEM; 474 } 475 if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){ 476 sqlite3SetString(&pParse->zErrMsg, db, "%s", sqlite3ErrStr(pParse->rc)); 477 } 478 assert( pzErrMsg!=0 ); 479 if( pParse->zErrMsg ){ 480 *pzErrMsg = pParse->zErrMsg; 481 sqlite3_log(pParse->rc, "%s", *pzErrMsg); 482 pParse->zErrMsg = 0; 483 nErr++; 484 } 485 if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){ 486 sqlite3VdbeDelete(pParse->pVdbe); 487 pParse->pVdbe = 0; 488 } 489 #ifndef SQLITE_OMIT_SHARED_CACHE 490 if( pParse->nested==0 ){ 491 sqlite3DbFree(db, pParse->aTableLock); 492 pParse->aTableLock = 0; 493 pParse->nTableLock = 0; 494 } 495 #endif 496 #ifndef SQLITE_OMIT_VIRTUALTABLE 497 sqlite3_free(pParse->apVtabLock); 498 #endif 499 500 if( !IN_DECLARE_VTAB ){ 501 /* If the pParse->declareVtab flag is set, do not delete any table 502 ** structure built up in pParse->pNewTable. The calling code (see vtab.c) 503 ** will take responsibility for freeing the Table structure. 504 */ 505 sqlite3DeleteTable(db, pParse->pNewTable); 506 } 507 508 sqlite3DeleteTrigger(db, pParse->pNewTrigger); 509 for(i=pParse->nzVar-1; i>=0; i--) sqlite3DbFree(db, pParse->azVar[i]); 510 sqlite3DbFree(db, pParse->azVar); 511 sqlite3DbFree(db, pParse->aAlias); 512 while( pParse->pAinc ){ 513 AutoincInfo *p = pParse->pAinc; 514 pParse->pAinc = p->pNext; 515 sqlite3DbFree(db, p); 516 } 517 while( pParse->pZombieTab ){ 518 Table *p = pParse->pZombieTab; 519 pParse->pZombieTab = p->pNextZombie; 520 sqlite3DeleteTable(db, p); 521 } 522 if( nErr>0 && pParse->rc==SQLITE_OK ){ 523 pParse->rc = SQLITE_ERROR; 524 } 525 return nErr; 526 } 527