1 /* 2 ** 2002 February 23 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 ** This file contains the C-language implementations for many of the SQL 13 ** functions of SQLite. (Some function, and in particular the date and 14 ** time functions, are implemented separately.) 15 */ 16 #include "sqliteInt.h" 17 #include <stdlib.h> 18 #include <assert.h> 19 #include "vdbeInt.h" 20 21 /* 22 ** Return the collating function associated with a function. 23 */ 24 static CollSeq *sqlite3GetFuncCollSeq(sqlite3_context *context){ 25 VdbeOp *pOp; 26 assert( context->pVdbe!=0 ); 27 pOp = &context->pVdbe->aOp[context->iOp-1]; 28 assert( pOp->opcode==OP_CollSeq ); 29 assert( pOp->p4type==P4_COLLSEQ ); 30 return pOp->p4.pColl; 31 } 32 33 /* 34 ** Indicate that the accumulator load should be skipped on this 35 ** iteration of the aggregate loop. 36 */ 37 static void sqlite3SkipAccumulatorLoad(sqlite3_context *context){ 38 assert( context->isError<=0 ); 39 context->isError = -1; 40 context->skipFlag = 1; 41 } 42 43 /* 44 ** Implementation of the non-aggregate min() and max() functions 45 */ 46 static void minmaxFunc( 47 sqlite3_context *context, 48 int argc, 49 sqlite3_value **argv 50 ){ 51 int i; 52 int mask; /* 0 for min() or 0xffffffff for max() */ 53 int iBest; 54 CollSeq *pColl; 55 56 assert( argc>1 ); 57 mask = sqlite3_user_data(context)==0 ? 0 : -1; 58 pColl = sqlite3GetFuncCollSeq(context); 59 assert( pColl ); 60 assert( mask==-1 || mask==0 ); 61 iBest = 0; 62 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; 63 for(i=1; i<argc; i++){ 64 if( sqlite3_value_type(argv[i])==SQLITE_NULL ) return; 65 if( (sqlite3MemCompare(argv[iBest], argv[i], pColl)^mask)>=0 ){ 66 testcase( mask==0 ); 67 iBest = i; 68 } 69 } 70 sqlite3_result_value(context, argv[iBest]); 71 } 72 73 /* 74 ** Return the type of the argument. 75 */ 76 static void typeofFunc( 77 sqlite3_context *context, 78 int NotUsed, 79 sqlite3_value **argv 80 ){ 81 static const char *azType[] = { "integer", "real", "text", "blob", "null" }; 82 int i = sqlite3_value_type(argv[0]) - 1; 83 UNUSED_PARAMETER(NotUsed); 84 assert( i>=0 && i<ArraySize(azType) ); 85 assert( SQLITE_INTEGER==1 ); 86 assert( SQLITE_FLOAT==2 ); 87 assert( SQLITE_TEXT==3 ); 88 assert( SQLITE_BLOB==4 ); 89 assert( SQLITE_NULL==5 ); 90 /* EVIDENCE-OF: R-01470-60482 The sqlite3_value_type(V) interface returns 91 ** the datatype code for the initial datatype of the sqlite3_value object 92 ** V. The returned value is one of SQLITE_INTEGER, SQLITE_FLOAT, 93 ** SQLITE_TEXT, SQLITE_BLOB, or SQLITE_NULL. */ 94 sqlite3_result_text(context, azType[i], -1, SQLITE_STATIC); 95 } 96 97 98 /* 99 ** Implementation of the length() function 100 */ 101 static void lengthFunc( 102 sqlite3_context *context, 103 int argc, 104 sqlite3_value **argv 105 ){ 106 assert( argc==1 ); 107 UNUSED_PARAMETER(argc); 108 switch( sqlite3_value_type(argv[0]) ){ 109 case SQLITE_BLOB: 110 case SQLITE_INTEGER: 111 case SQLITE_FLOAT: { 112 sqlite3_result_int(context, sqlite3_value_bytes(argv[0])); 113 break; 114 } 115 case SQLITE_TEXT: { 116 const unsigned char *z = sqlite3_value_text(argv[0]); 117 const unsigned char *z0; 118 unsigned char c; 119 if( z==0 ) return; 120 z0 = z; 121 while( (c = *z)!=0 ){ 122 z++; 123 if( c>=0xc0 ){ 124 while( (*z & 0xc0)==0x80 ){ z++; z0++; } 125 } 126 } 127 sqlite3_result_int(context, (int)(z-z0)); 128 break; 129 } 130 default: { 131 sqlite3_result_null(context); 132 break; 133 } 134 } 135 } 136 137 /* 138 ** Implementation of the abs() function. 139 ** 140 ** IMP: R-23979-26855 The abs(X) function returns the absolute value of 141 ** the numeric argument X. 142 */ 143 static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ 144 assert( argc==1 ); 145 UNUSED_PARAMETER(argc); 146 switch( sqlite3_value_type(argv[0]) ){ 147 case SQLITE_INTEGER: { 148 i64 iVal = sqlite3_value_int64(argv[0]); 149 if( iVal<0 ){ 150 if( iVal==SMALLEST_INT64 ){ 151 /* IMP: R-31676-45509 If X is the integer -9223372036854775808 152 ** then abs(X) throws an integer overflow error since there is no 153 ** equivalent positive 64-bit two complement value. */ 154 sqlite3_result_error(context, "integer overflow", -1); 155 return; 156 } 157 iVal = -iVal; 158 } 159 sqlite3_result_int64(context, iVal); 160 break; 161 } 162 case SQLITE_NULL: { 163 /* IMP: R-37434-19929 Abs(X) returns NULL if X is NULL. */ 164 sqlite3_result_null(context); 165 break; 166 } 167 default: { 168 /* Because sqlite3_value_double() returns 0.0 if the argument is not 169 ** something that can be converted into a number, we have: 170 ** IMP: R-01992-00519 Abs(X) returns 0.0 if X is a string or blob 171 ** that cannot be converted to a numeric value. 172 */ 173 double rVal = sqlite3_value_double(argv[0]); 174 if( rVal<0 ) rVal = -rVal; 175 sqlite3_result_double(context, rVal); 176 break; 177 } 178 } 179 } 180 181 /* 182 ** Implementation of the instr() function. 183 ** 184 ** instr(haystack,needle) finds the first occurrence of needle 185 ** in haystack and returns the number of previous characters plus 1, 186 ** or 0 if needle does not occur within haystack. 187 ** 188 ** If both haystack and needle are BLOBs, then the result is one more than 189 ** the number of bytes in haystack prior to the first occurrence of needle, 190 ** or 0 if needle never occurs in haystack. 191 */ 192 static void instrFunc( 193 sqlite3_context *context, 194 int argc, 195 sqlite3_value **argv 196 ){ 197 const unsigned char *zHaystack; 198 const unsigned char *zNeedle; 199 int nHaystack; 200 int nNeedle; 201 int typeHaystack, typeNeedle; 202 int N = 1; 203 int isText; 204 unsigned char firstChar; 205 206 UNUSED_PARAMETER(argc); 207 typeHaystack = sqlite3_value_type(argv[0]); 208 typeNeedle = sqlite3_value_type(argv[1]); 209 if( typeHaystack==SQLITE_NULL || typeNeedle==SQLITE_NULL ) return; 210 nHaystack = sqlite3_value_bytes(argv[0]); 211 nNeedle = sqlite3_value_bytes(argv[1]); 212 if( nNeedle>0 ){ 213 if( typeHaystack==SQLITE_BLOB && typeNeedle==SQLITE_BLOB ){ 214 zHaystack = sqlite3_value_blob(argv[0]); 215 zNeedle = sqlite3_value_blob(argv[1]); 216 isText = 0; 217 }else{ 218 zHaystack = sqlite3_value_text(argv[0]); 219 zNeedle = sqlite3_value_text(argv[1]); 220 isText = 1; 221 } 222 if( zNeedle==0 || (nHaystack && zHaystack==0) ) return; 223 firstChar = zNeedle[0]; 224 while( nNeedle<=nHaystack 225 && (zHaystack[0]!=firstChar || memcmp(zHaystack, zNeedle, nNeedle)!=0) 226 ){ 227 N++; 228 do{ 229 nHaystack--; 230 zHaystack++; 231 }while( isText && (zHaystack[0]&0xc0)==0x80 ); 232 } 233 if( nNeedle>nHaystack ) N = 0; 234 } 235 sqlite3_result_int(context, N); 236 } 237 238 /* 239 ** Implementation of the printf() function. 240 */ 241 static void printfFunc( 242 sqlite3_context *context, 243 int argc, 244 sqlite3_value **argv 245 ){ 246 PrintfArguments x; 247 StrAccum str; 248 const char *zFormat; 249 int n; 250 sqlite3 *db = sqlite3_context_db_handle(context); 251 252 if( argc>=1 && (zFormat = (const char*)sqlite3_value_text(argv[0]))!=0 ){ 253 x.nArg = argc-1; 254 x.nUsed = 0; 255 x.apArg = argv+1; 256 sqlite3StrAccumInit(&str, db, 0, 0, db->aLimit[SQLITE_LIMIT_LENGTH]); 257 str.printfFlags = SQLITE_PRINTF_SQLFUNC; 258 sqlite3_str_appendf(&str, zFormat, &x); 259 n = str.nChar; 260 sqlite3_result_text(context, sqlite3StrAccumFinish(&str), n, 261 SQLITE_DYNAMIC); 262 } 263 } 264 265 /* 266 ** Implementation of the substr() function. 267 ** 268 ** substr(x,p1,p2) returns p2 characters of x[] beginning with p1. 269 ** p1 is 1-indexed. So substr(x,1,1) returns the first character 270 ** of x. If x is text, then we actually count UTF-8 characters. 271 ** If x is a blob, then we count bytes. 272 ** 273 ** If p1 is negative, then we begin abs(p1) from the end of x[]. 274 ** 275 ** If p2 is negative, return the p2 characters preceding p1. 276 */ 277 static void substrFunc( 278 sqlite3_context *context, 279 int argc, 280 sqlite3_value **argv 281 ){ 282 const unsigned char *z; 283 const unsigned char *z2; 284 int len; 285 int p0type; 286 i64 p1, p2; 287 int negP2 = 0; 288 289 assert( argc==3 || argc==2 ); 290 if( sqlite3_value_type(argv[1])==SQLITE_NULL 291 || (argc==3 && sqlite3_value_type(argv[2])==SQLITE_NULL) 292 ){ 293 return; 294 } 295 p0type = sqlite3_value_type(argv[0]); 296 p1 = sqlite3_value_int(argv[1]); 297 if( p0type==SQLITE_BLOB ){ 298 len = sqlite3_value_bytes(argv[0]); 299 z = sqlite3_value_blob(argv[0]); 300 if( z==0 ) return; 301 assert( len==sqlite3_value_bytes(argv[0]) ); 302 }else{ 303 z = sqlite3_value_text(argv[0]); 304 if( z==0 ) return; 305 len = 0; 306 if( p1<0 ){ 307 for(z2=z; *z2; len++){ 308 SQLITE_SKIP_UTF8(z2); 309 } 310 } 311 } 312 #ifdef SQLITE_SUBSTR_COMPATIBILITY 313 /* If SUBSTR_COMPATIBILITY is defined then substr(X,0,N) work the same as 314 ** as substr(X,1,N) - it returns the first N characters of X. This 315 ** is essentially a back-out of the bug-fix in check-in [5fc125d362df4b8] 316 ** from 2009-02-02 for compatibility of applications that exploited the 317 ** old buggy behavior. */ 318 if( p1==0 ) p1 = 1; /* <rdar://problem/6778339> */ 319 #endif 320 if( argc==3 ){ 321 p2 = sqlite3_value_int(argv[2]); 322 if( p2<0 ){ 323 p2 = -p2; 324 negP2 = 1; 325 } 326 }else{ 327 p2 = sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH]; 328 } 329 if( p1<0 ){ 330 p1 += len; 331 if( p1<0 ){ 332 p2 += p1; 333 if( p2<0 ) p2 = 0; 334 p1 = 0; 335 } 336 }else if( p1>0 ){ 337 p1--; 338 }else if( p2>0 ){ 339 p2--; 340 } 341 if( negP2 ){ 342 p1 -= p2; 343 if( p1<0 ){ 344 p2 += p1; 345 p1 = 0; 346 } 347 } 348 assert( p1>=0 && p2>=0 ); 349 if( p0type!=SQLITE_BLOB ){ 350 while( *z && p1 ){ 351 SQLITE_SKIP_UTF8(z); 352 p1--; 353 } 354 for(z2=z; *z2 && p2; p2--){ 355 SQLITE_SKIP_UTF8(z2); 356 } 357 sqlite3_result_text64(context, (char*)z, z2-z, SQLITE_TRANSIENT, 358 SQLITE_UTF8); 359 }else{ 360 if( p1+p2>len ){ 361 p2 = len-p1; 362 if( p2<0 ) p2 = 0; 363 } 364 sqlite3_result_blob64(context, (char*)&z[p1], (u64)p2, SQLITE_TRANSIENT); 365 } 366 } 367 368 /* 369 ** Implementation of the round() function 370 */ 371 #ifndef SQLITE_OMIT_FLOATING_POINT 372 static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ 373 int n = 0; 374 double r; 375 char *zBuf; 376 assert( argc==1 || argc==2 ); 377 if( argc==2 ){ 378 if( SQLITE_NULL==sqlite3_value_type(argv[1]) ) return; 379 n = sqlite3_value_int(argv[1]); 380 if( n>30 ) n = 30; 381 if( n<0 ) n = 0; 382 } 383 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; 384 r = sqlite3_value_double(argv[0]); 385 /* If Y==0 and X will fit in a 64-bit int, 386 ** handle the rounding directly, 387 ** otherwise use printf. 388 */ 389 if( n==0 && r>=0 && r<LARGEST_INT64-1 ){ 390 r = (double)((sqlite_int64)(r+0.5)); 391 }else if( n==0 && r<0 && (-r)<LARGEST_INT64-1 ){ 392 r = -(double)((sqlite_int64)((-r)+0.5)); 393 }else{ 394 zBuf = sqlite3_mprintf("%.*f",n,r); 395 if( zBuf==0 ){ 396 sqlite3_result_error_nomem(context); 397 return; 398 } 399 sqlite3AtoF(zBuf, &r, sqlite3Strlen30(zBuf), SQLITE_UTF8); 400 sqlite3_free(zBuf); 401 } 402 sqlite3_result_double(context, r); 403 } 404 #endif 405 406 /* 407 ** Allocate nByte bytes of space using sqlite3Malloc(). If the 408 ** allocation fails, call sqlite3_result_error_nomem() to notify 409 ** the database handle that malloc() has failed and return NULL. 410 ** If nByte is larger than the maximum string or blob length, then 411 ** raise an SQLITE_TOOBIG exception and return NULL. 412 */ 413 static void *contextMalloc(sqlite3_context *context, i64 nByte){ 414 char *z; 415 sqlite3 *db = sqlite3_context_db_handle(context); 416 assert( nByte>0 ); 417 testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH] ); 418 testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH]+1 ); 419 if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){ 420 sqlite3_result_error_toobig(context); 421 z = 0; 422 }else{ 423 z = sqlite3Malloc(nByte); 424 if( !z ){ 425 sqlite3_result_error_nomem(context); 426 } 427 } 428 return z; 429 } 430 431 /* 432 ** Implementation of the upper() and lower() SQL functions. 433 */ 434 static void upperFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ 435 char *z1; 436 const char *z2; 437 int i, n; 438 UNUSED_PARAMETER(argc); 439 z2 = (char*)sqlite3_value_text(argv[0]); 440 n = sqlite3_value_bytes(argv[0]); 441 /* Verify that the call to _bytes() does not invalidate the _text() pointer */ 442 assert( z2==(char*)sqlite3_value_text(argv[0]) ); 443 if( z2 ){ 444 z1 = contextMalloc(context, ((i64)n)+1); 445 if( z1 ){ 446 for(i=0; i<n; i++){ 447 z1[i] = (char)sqlite3Toupper(z2[i]); 448 } 449 sqlite3_result_text(context, z1, n, sqlite3_free); 450 } 451 } 452 } 453 static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ 454 char *z1; 455 const char *z2; 456 int i, n; 457 UNUSED_PARAMETER(argc); 458 z2 = (char*)sqlite3_value_text(argv[0]); 459 n = sqlite3_value_bytes(argv[0]); 460 /* Verify that the call to _bytes() does not invalidate the _text() pointer */ 461 assert( z2==(char*)sqlite3_value_text(argv[0]) ); 462 if( z2 ){ 463 z1 = contextMalloc(context, ((i64)n)+1); 464 if( z1 ){ 465 for(i=0; i<n; i++){ 466 z1[i] = sqlite3Tolower(z2[i]); 467 } 468 sqlite3_result_text(context, z1, n, sqlite3_free); 469 } 470 } 471 } 472 473 /* 474 ** Some functions like COALESCE() and IFNULL() and UNLIKELY() are implemented 475 ** as VDBE code so that unused argument values do not have to be computed. 476 ** However, we still need some kind of function implementation for this 477 ** routines in the function table. The noopFunc macro provides this. 478 ** noopFunc will never be called so it doesn't matter what the implementation 479 ** is. We might as well use the "version()" function as a substitute. 480 */ 481 #define noopFunc versionFunc /* Substitute function - never called */ 482 483 /* 484 ** Implementation of random(). Return a random integer. 485 */ 486 static void randomFunc( 487 sqlite3_context *context, 488 int NotUsed, 489 sqlite3_value **NotUsed2 490 ){ 491 sqlite_int64 r; 492 UNUSED_PARAMETER2(NotUsed, NotUsed2); 493 sqlite3_randomness(sizeof(r), &r); 494 if( r<0 ){ 495 /* We need to prevent a random number of 0x8000000000000000 496 ** (or -9223372036854775808) since when you do abs() of that 497 ** number of you get the same value back again. To do this 498 ** in a way that is testable, mask the sign bit off of negative 499 ** values, resulting in a positive value. Then take the 500 ** 2s complement of that positive value. The end result can 501 ** therefore be no less than -9223372036854775807. 502 */ 503 r = -(r & LARGEST_INT64); 504 } 505 sqlite3_result_int64(context, r); 506 } 507 508 /* 509 ** Implementation of randomblob(N). Return a random blob 510 ** that is N bytes long. 511 */ 512 static void randomBlob( 513 sqlite3_context *context, 514 int argc, 515 sqlite3_value **argv 516 ){ 517 sqlite3_int64 n; 518 unsigned char *p; 519 assert( argc==1 ); 520 UNUSED_PARAMETER(argc); 521 n = sqlite3_value_int64(argv[0]); 522 if( n<1 ){ 523 n = 1; 524 } 525 p = contextMalloc(context, n); 526 if( p ){ 527 sqlite3_randomness(n, p); 528 sqlite3_result_blob(context, (char*)p, n, sqlite3_free); 529 } 530 } 531 532 /* 533 ** Implementation of the last_insert_rowid() SQL function. The return 534 ** value is the same as the sqlite3_last_insert_rowid() API function. 535 */ 536 static void last_insert_rowid( 537 sqlite3_context *context, 538 int NotUsed, 539 sqlite3_value **NotUsed2 540 ){ 541 sqlite3 *db = sqlite3_context_db_handle(context); 542 UNUSED_PARAMETER2(NotUsed, NotUsed2); 543 /* IMP: R-51513-12026 The last_insert_rowid() SQL function is a 544 ** wrapper around the sqlite3_last_insert_rowid() C/C++ interface 545 ** function. */ 546 sqlite3_result_int64(context, sqlite3_last_insert_rowid(db)); 547 } 548 549 /* 550 ** Implementation of the changes() SQL function. 551 ** 552 ** IMP: R-62073-11209 The changes() SQL function is a wrapper 553 ** around the sqlite3_changes() C/C++ function and hence follows the same 554 ** rules for counting changes. 555 */ 556 static void changes( 557 sqlite3_context *context, 558 int NotUsed, 559 sqlite3_value **NotUsed2 560 ){ 561 sqlite3 *db = sqlite3_context_db_handle(context); 562 UNUSED_PARAMETER2(NotUsed, NotUsed2); 563 sqlite3_result_int(context, sqlite3_changes(db)); 564 } 565 566 /* 567 ** Implementation of the total_changes() SQL function. The return value is 568 ** the same as the sqlite3_total_changes() API function. 569 */ 570 static void total_changes( 571 sqlite3_context *context, 572 int NotUsed, 573 sqlite3_value **NotUsed2 574 ){ 575 sqlite3 *db = sqlite3_context_db_handle(context); 576 UNUSED_PARAMETER2(NotUsed, NotUsed2); 577 /* IMP: R-52756-41993 This function is a wrapper around the 578 ** sqlite3_total_changes() C/C++ interface. */ 579 sqlite3_result_int(context, sqlite3_total_changes(db)); 580 } 581 582 /* 583 ** A structure defining how to do GLOB-style comparisons. 584 */ 585 struct compareInfo { 586 u8 matchAll; /* "*" or "%" */ 587 u8 matchOne; /* "?" or "_" */ 588 u8 matchSet; /* "[" or 0 */ 589 u8 noCase; /* true to ignore case differences */ 590 }; 591 592 /* 593 ** For LIKE and GLOB matching on EBCDIC machines, assume that every 594 ** character is exactly one byte in size. Also, provde the Utf8Read() 595 ** macro for fast reading of the next character in the common case where 596 ** the next character is ASCII. 597 */ 598 #if defined(SQLITE_EBCDIC) 599 # define sqlite3Utf8Read(A) (*((*A)++)) 600 # define Utf8Read(A) (*(A++)) 601 #else 602 # define Utf8Read(A) (A[0]<0x80?*(A++):sqlite3Utf8Read(&A)) 603 #endif 604 605 static const struct compareInfo globInfo = { '*', '?', '[', 0 }; 606 /* The correct SQL-92 behavior is for the LIKE operator to ignore 607 ** case. Thus 'a' LIKE 'A' would be true. */ 608 static const struct compareInfo likeInfoNorm = { '%', '_', 0, 1 }; 609 /* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator 610 ** is case sensitive causing 'a' LIKE 'A' to be false */ 611 static const struct compareInfo likeInfoAlt = { '%', '_', 0, 0 }; 612 613 /* 614 ** Possible error returns from patternMatch() 615 */ 616 #define SQLITE_MATCH 0 617 #define SQLITE_NOMATCH 1 618 #define SQLITE_NOWILDCARDMATCH 2 619 620 /* 621 ** Compare two UTF-8 strings for equality where the first string is 622 ** a GLOB or LIKE expression. Return values: 623 ** 624 ** SQLITE_MATCH: Match 625 ** SQLITE_NOMATCH: No match 626 ** SQLITE_NOWILDCARDMATCH: No match in spite of having * or % wildcards. 627 ** 628 ** Globbing rules: 629 ** 630 ** '*' Matches any sequence of zero or more characters. 631 ** 632 ** '?' Matches exactly one character. 633 ** 634 ** [...] Matches one character from the enclosed list of 635 ** characters. 636 ** 637 ** [^...] Matches one character not in the enclosed list. 638 ** 639 ** With the [...] and [^...] matching, a ']' character can be included 640 ** in the list by making it the first character after '[' or '^'. A 641 ** range of characters can be specified using '-'. Example: 642 ** "[a-z]" matches any single lower-case letter. To match a '-', make 643 ** it the last character in the list. 644 ** 645 ** Like matching rules: 646 ** 647 ** '%' Matches any sequence of zero or more characters 648 ** 649 *** '_' Matches any one character 650 ** 651 ** Ec Where E is the "esc" character and c is any other 652 ** character, including '%', '_', and esc, match exactly c. 653 ** 654 ** The comments within this routine usually assume glob matching. 655 ** 656 ** This routine is usually quick, but can be N**2 in the worst case. 657 */ 658 static int patternCompare( 659 const u8 *zPattern, /* The glob pattern */ 660 const u8 *zString, /* The string to compare against the glob */ 661 const struct compareInfo *pInfo, /* Information about how to do the compare */ 662 u32 matchOther /* The escape char (LIKE) or '[' (GLOB) */ 663 ){ 664 u32 c, c2; /* Next pattern and input string chars */ 665 u32 matchOne = pInfo->matchOne; /* "?" or "_" */ 666 u32 matchAll = pInfo->matchAll; /* "*" or "%" */ 667 u8 noCase = pInfo->noCase; /* True if uppercase==lowercase */ 668 const u8 *zEscaped = 0; /* One past the last escaped input char */ 669 670 while( (c = Utf8Read(zPattern))!=0 ){ 671 if( c==matchAll ){ /* Match "*" */ 672 /* Skip over multiple "*" characters in the pattern. If there 673 ** are also "?" characters, skip those as well, but consume a 674 ** single character of the input string for each "?" skipped */ 675 while( (c=Utf8Read(zPattern)) == matchAll || c == matchOne ){ 676 if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){ 677 return SQLITE_NOWILDCARDMATCH; 678 } 679 } 680 if( c==0 ){ 681 return SQLITE_MATCH; /* "*" at the end of the pattern matches */ 682 }else if( c==matchOther ){ 683 if( pInfo->matchSet==0 ){ 684 c = sqlite3Utf8Read(&zPattern); 685 if( c==0 ) return SQLITE_NOWILDCARDMATCH; 686 }else{ 687 /* "[...]" immediately follows the "*". We have to do a slow 688 ** recursive search in this case, but it is an unusual case. */ 689 assert( matchOther<0x80 ); /* '[' is a single-byte character */ 690 while( *zString ){ 691 int bMatch = patternCompare(&zPattern[-1],zString,pInfo,matchOther); 692 if( bMatch!=SQLITE_NOMATCH ) return bMatch; 693 SQLITE_SKIP_UTF8(zString); 694 } 695 return SQLITE_NOWILDCARDMATCH; 696 } 697 } 698 699 /* At this point variable c contains the first character of the 700 ** pattern string past the "*". Search in the input string for the 701 ** first matching character and recursively continue the match from 702 ** that point. 703 ** 704 ** For a case-insensitive search, set variable cx to be the same as 705 ** c but in the other case and search the input string for either 706 ** c or cx. 707 */ 708 if( c<=0x80 ){ 709 char zStop[3]; 710 int bMatch; 711 if( noCase ){ 712 zStop[0] = sqlite3Toupper(c); 713 zStop[1] = sqlite3Tolower(c); 714 zStop[2] = 0; 715 }else{ 716 zStop[0] = c; 717 zStop[1] = 0; 718 } 719 while(1){ 720 zString += strcspn((const char*)zString, zStop); 721 if( zString[0]==0 ) break; 722 zString++; 723 bMatch = patternCompare(zPattern,zString,pInfo,matchOther); 724 if( bMatch!=SQLITE_NOMATCH ) return bMatch; 725 } 726 }else{ 727 int bMatch; 728 while( (c2 = Utf8Read(zString))!=0 ){ 729 if( c2!=c ) continue; 730 bMatch = patternCompare(zPattern,zString,pInfo,matchOther); 731 if( bMatch!=SQLITE_NOMATCH ) return bMatch; 732 } 733 } 734 return SQLITE_NOWILDCARDMATCH; 735 } 736 if( c==matchOther ){ 737 if( pInfo->matchSet==0 ){ 738 c = sqlite3Utf8Read(&zPattern); 739 if( c==0 ) return SQLITE_NOMATCH; 740 zEscaped = zPattern; 741 }else{ 742 u32 prior_c = 0; 743 int seen = 0; 744 int invert = 0; 745 c = sqlite3Utf8Read(&zString); 746 if( c==0 ) return SQLITE_NOMATCH; 747 c2 = sqlite3Utf8Read(&zPattern); 748 if( c2=='^' ){ 749 invert = 1; 750 c2 = sqlite3Utf8Read(&zPattern); 751 } 752 if( c2==']' ){ 753 if( c==']' ) seen = 1; 754 c2 = sqlite3Utf8Read(&zPattern); 755 } 756 while( c2 && c2!=']' ){ 757 if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){ 758 c2 = sqlite3Utf8Read(&zPattern); 759 if( c>=prior_c && c<=c2 ) seen = 1; 760 prior_c = 0; 761 }else{ 762 if( c==c2 ){ 763 seen = 1; 764 } 765 prior_c = c2; 766 } 767 c2 = sqlite3Utf8Read(&zPattern); 768 } 769 if( c2==0 || (seen ^ invert)==0 ){ 770 return SQLITE_NOMATCH; 771 } 772 continue; 773 } 774 } 775 c2 = Utf8Read(zString); 776 if( c==c2 ) continue; 777 if( noCase && sqlite3Tolower(c)==sqlite3Tolower(c2) && c<0x80 && c2<0x80 ){ 778 continue; 779 } 780 if( c==matchOne && zPattern!=zEscaped && c2!=0 ) continue; 781 return SQLITE_NOMATCH; 782 } 783 return *zString==0 ? SQLITE_MATCH : SQLITE_NOMATCH; 784 } 785 786 /* 787 ** The sqlite3_strglob() interface. Return 0 on a match (like strcmp()) and 788 ** non-zero if there is no match. 789 */ 790 int sqlite3_strglob(const char *zGlobPattern, const char *zString){ 791 return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, '['); 792 } 793 794 /* 795 ** The sqlite3_strlike() interface. Return 0 on a match and non-zero for 796 ** a miss - like strcmp(). 797 */ 798 int sqlite3_strlike(const char *zPattern, const char *zStr, unsigned int esc){ 799 return patternCompare((u8*)zPattern, (u8*)zStr, &likeInfoNorm, esc); 800 } 801 802 /* 803 ** Count the number of times that the LIKE operator (or GLOB which is 804 ** just a variation of LIKE) gets called. This is used for testing 805 ** only. 806 */ 807 #ifdef SQLITE_TEST 808 int sqlite3_like_count = 0; 809 #endif 810 811 812 /* 813 ** Implementation of the like() SQL function. This function implements 814 ** the build-in LIKE operator. The first argument to the function is the 815 ** pattern and the second argument is the string. So, the SQL statements: 816 ** 817 ** A LIKE B 818 ** 819 ** is implemented as like(B,A). 820 ** 821 ** This same function (with a different compareInfo structure) computes 822 ** the GLOB operator. 823 */ 824 static void likeFunc( 825 sqlite3_context *context, 826 int argc, 827 sqlite3_value **argv 828 ){ 829 const unsigned char *zA, *zB; 830 u32 escape; 831 int nPat; 832 sqlite3 *db = sqlite3_context_db_handle(context); 833 struct compareInfo *pInfo = sqlite3_user_data(context); 834 835 #ifdef SQLITE_LIKE_DOESNT_MATCH_BLOBS 836 if( sqlite3_value_type(argv[0])==SQLITE_BLOB 837 || sqlite3_value_type(argv[1])==SQLITE_BLOB 838 ){ 839 #ifdef SQLITE_TEST 840 sqlite3_like_count++; 841 #endif 842 sqlite3_result_int(context, 0); 843 return; 844 } 845 #endif 846 zB = sqlite3_value_text(argv[0]); 847 zA = sqlite3_value_text(argv[1]); 848 849 /* Limit the length of the LIKE or GLOB pattern to avoid problems 850 ** of deep recursion and N*N behavior in patternCompare(). 851 */ 852 nPat = sqlite3_value_bytes(argv[0]); 853 testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ); 854 testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]+1 ); 855 if( nPat > db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ){ 856 sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1); 857 return; 858 } 859 assert( zB==sqlite3_value_text(argv[0]) ); /* Encoding did not change */ 860 861 if( argc==3 ){ 862 /* The escape character string must consist of a single UTF-8 character. 863 ** Otherwise, return an error. 864 */ 865 const unsigned char *zEsc = sqlite3_value_text(argv[2]); 866 if( zEsc==0 ) return; 867 if( sqlite3Utf8CharLen((char*)zEsc, -1)!=1 ){ 868 sqlite3_result_error(context, 869 "ESCAPE expression must be a single character", -1); 870 return; 871 } 872 escape = sqlite3Utf8Read(&zEsc); 873 }else{ 874 escape = pInfo->matchSet; 875 } 876 if( zA && zB ){ 877 #ifdef SQLITE_TEST 878 sqlite3_like_count++; 879 #endif 880 sqlite3_result_int(context, 881 patternCompare(zB, zA, pInfo, escape)==SQLITE_MATCH); 882 } 883 } 884 885 /* 886 ** Implementation of the NULLIF(x,y) function. The result is the first 887 ** argument if the arguments are different. The result is NULL if the 888 ** arguments are equal to each other. 889 */ 890 static void nullifFunc( 891 sqlite3_context *context, 892 int NotUsed, 893 sqlite3_value **argv 894 ){ 895 CollSeq *pColl = sqlite3GetFuncCollSeq(context); 896 UNUSED_PARAMETER(NotUsed); 897 if( sqlite3MemCompare(argv[0], argv[1], pColl)!=0 ){ 898 sqlite3_result_value(context, argv[0]); 899 } 900 } 901 902 /* 903 ** Implementation of the sqlite_version() function. The result is the version 904 ** of the SQLite library that is running. 905 */ 906 static void versionFunc( 907 sqlite3_context *context, 908 int NotUsed, 909 sqlite3_value **NotUsed2 910 ){ 911 UNUSED_PARAMETER2(NotUsed, NotUsed2); 912 /* IMP: R-48699-48617 This function is an SQL wrapper around the 913 ** sqlite3_libversion() C-interface. */ 914 sqlite3_result_text(context, sqlite3_libversion(), -1, SQLITE_STATIC); 915 } 916 917 /* 918 ** Implementation of the sqlite_source_id() function. The result is a string 919 ** that identifies the particular version of the source code used to build 920 ** SQLite. 921 */ 922 static void sourceidFunc( 923 sqlite3_context *context, 924 int NotUsed, 925 sqlite3_value **NotUsed2 926 ){ 927 UNUSED_PARAMETER2(NotUsed, NotUsed2); 928 /* IMP: R-24470-31136 This function is an SQL wrapper around the 929 ** sqlite3_sourceid() C interface. */ 930 sqlite3_result_text(context, sqlite3_sourceid(), -1, SQLITE_STATIC); 931 } 932 933 /* 934 ** Implementation of the sqlite_log() function. This is a wrapper around 935 ** sqlite3_log(). The return value is NULL. The function exists purely for 936 ** its side-effects. 937 */ 938 static void errlogFunc( 939 sqlite3_context *context, 940 int argc, 941 sqlite3_value **argv 942 ){ 943 UNUSED_PARAMETER(argc); 944 UNUSED_PARAMETER(context); 945 sqlite3_log(sqlite3_value_int(argv[0]), "%s", sqlite3_value_text(argv[1])); 946 } 947 948 /* 949 ** Implementation of the sqlite_compileoption_used() function. 950 ** The result is an integer that identifies if the compiler option 951 ** was used to build SQLite. 952 */ 953 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 954 static void compileoptionusedFunc( 955 sqlite3_context *context, 956 int argc, 957 sqlite3_value **argv 958 ){ 959 const char *zOptName; 960 assert( argc==1 ); 961 UNUSED_PARAMETER(argc); 962 /* IMP: R-39564-36305 The sqlite_compileoption_used() SQL 963 ** function is a wrapper around the sqlite3_compileoption_used() C/C++ 964 ** function. 965 */ 966 if( (zOptName = (const char*)sqlite3_value_text(argv[0]))!=0 ){ 967 sqlite3_result_int(context, sqlite3_compileoption_used(zOptName)); 968 } 969 } 970 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ 971 972 /* 973 ** Implementation of the sqlite_compileoption_get() function. 974 ** The result is a string that identifies the compiler options 975 ** used to build SQLite. 976 */ 977 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 978 static void compileoptiongetFunc( 979 sqlite3_context *context, 980 int argc, 981 sqlite3_value **argv 982 ){ 983 int n; 984 assert( argc==1 ); 985 UNUSED_PARAMETER(argc); 986 /* IMP: R-04922-24076 The sqlite_compileoption_get() SQL function 987 ** is a wrapper around the sqlite3_compileoption_get() C/C++ function. 988 */ 989 n = sqlite3_value_int(argv[0]); 990 sqlite3_result_text(context, sqlite3_compileoption_get(n), -1, SQLITE_STATIC); 991 } 992 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ 993 994 /* Array for converting from half-bytes (nybbles) into ASCII hex 995 ** digits. */ 996 static const char hexdigits[] = { 997 '0', '1', '2', '3', '4', '5', '6', '7', 998 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' 999 }; 1000 1001 /* 1002 ** Implementation of the QUOTE() function. This function takes a single 1003 ** argument. If the argument is numeric, the return value is the same as 1004 ** the argument. If the argument is NULL, the return value is the string 1005 ** "NULL". Otherwise, the argument is enclosed in single quotes with 1006 ** single-quote escapes. 1007 */ 1008 static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ 1009 assert( argc==1 ); 1010 UNUSED_PARAMETER(argc); 1011 switch( sqlite3_value_type(argv[0]) ){ 1012 case SQLITE_FLOAT: { 1013 double r1, r2; 1014 char zBuf[50]; 1015 r1 = sqlite3_value_double(argv[0]); 1016 sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.15g", r1); 1017 sqlite3AtoF(zBuf, &r2, 20, SQLITE_UTF8); 1018 if( r1!=r2 ){ 1019 sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.20e", r1); 1020 } 1021 sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT); 1022 break; 1023 } 1024 case SQLITE_INTEGER: { 1025 sqlite3_result_value(context, argv[0]); 1026 break; 1027 } 1028 case SQLITE_BLOB: { 1029 char *zText = 0; 1030 char const *zBlob = sqlite3_value_blob(argv[0]); 1031 int nBlob = sqlite3_value_bytes(argv[0]); 1032 assert( zBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */ 1033 zText = (char *)contextMalloc(context, (2*(i64)nBlob)+4); 1034 if( zText ){ 1035 int i; 1036 for(i=0; i<nBlob; i++){ 1037 zText[(i*2)+2] = hexdigits[(zBlob[i]>>4)&0x0F]; 1038 zText[(i*2)+3] = hexdigits[(zBlob[i])&0x0F]; 1039 } 1040 zText[(nBlob*2)+2] = '\''; 1041 zText[(nBlob*2)+3] = '\0'; 1042 zText[0] = 'X'; 1043 zText[1] = '\''; 1044 sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT); 1045 sqlite3_free(zText); 1046 } 1047 break; 1048 } 1049 case SQLITE_TEXT: { 1050 int i,j; 1051 u64 n; 1052 const unsigned char *zArg = sqlite3_value_text(argv[0]); 1053 char *z; 1054 1055 if( zArg==0 ) return; 1056 for(i=0, n=0; zArg[i]; i++){ if( zArg[i]=='\'' ) n++; } 1057 z = contextMalloc(context, ((i64)i)+((i64)n)+3); 1058 if( z ){ 1059 z[0] = '\''; 1060 for(i=0, j=1; zArg[i]; i++){ 1061 z[j++] = zArg[i]; 1062 if( zArg[i]=='\'' ){ 1063 z[j++] = '\''; 1064 } 1065 } 1066 z[j++] = '\''; 1067 z[j] = 0; 1068 sqlite3_result_text(context, z, j, sqlite3_free); 1069 } 1070 break; 1071 } 1072 default: { 1073 assert( sqlite3_value_type(argv[0])==SQLITE_NULL ); 1074 sqlite3_result_text(context, "NULL", 4, SQLITE_STATIC); 1075 break; 1076 } 1077 } 1078 } 1079 1080 /* 1081 ** The unicode() function. Return the integer unicode code-point value 1082 ** for the first character of the input string. 1083 */ 1084 static void unicodeFunc( 1085 sqlite3_context *context, 1086 int argc, 1087 sqlite3_value **argv 1088 ){ 1089 const unsigned char *z = sqlite3_value_text(argv[0]); 1090 (void)argc; 1091 if( z && z[0] ) sqlite3_result_int(context, sqlite3Utf8Read(&z)); 1092 } 1093 1094 /* 1095 ** The char() function takes zero or more arguments, each of which is 1096 ** an integer. It constructs a string where each character of the string 1097 ** is the unicode character for the corresponding integer argument. 1098 */ 1099 static void charFunc( 1100 sqlite3_context *context, 1101 int argc, 1102 sqlite3_value **argv 1103 ){ 1104 unsigned char *z, *zOut; 1105 int i; 1106 zOut = z = sqlite3_malloc64( argc*4+1 ); 1107 if( z==0 ){ 1108 sqlite3_result_error_nomem(context); 1109 return; 1110 } 1111 for(i=0; i<argc; i++){ 1112 sqlite3_int64 x; 1113 unsigned c; 1114 x = sqlite3_value_int64(argv[i]); 1115 if( x<0 || x>0x10ffff ) x = 0xfffd; 1116 c = (unsigned)(x & 0x1fffff); 1117 if( c<0x00080 ){ 1118 *zOut++ = (u8)(c&0xFF); 1119 }else if( c<0x00800 ){ 1120 *zOut++ = 0xC0 + (u8)((c>>6)&0x1F); 1121 *zOut++ = 0x80 + (u8)(c & 0x3F); 1122 }else if( c<0x10000 ){ 1123 *zOut++ = 0xE0 + (u8)((c>>12)&0x0F); 1124 *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); 1125 *zOut++ = 0x80 + (u8)(c & 0x3F); 1126 }else{ 1127 *zOut++ = 0xF0 + (u8)((c>>18) & 0x07); 1128 *zOut++ = 0x80 + (u8)((c>>12) & 0x3F); 1129 *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); 1130 *zOut++ = 0x80 + (u8)(c & 0x3F); 1131 } \ 1132 } 1133 sqlite3_result_text64(context, (char*)z, zOut-z, sqlite3_free, SQLITE_UTF8); 1134 } 1135 1136 /* 1137 ** The hex() function. Interpret the argument as a blob. Return 1138 ** a hexadecimal rendering as text. 1139 */ 1140 static void hexFunc( 1141 sqlite3_context *context, 1142 int argc, 1143 sqlite3_value **argv 1144 ){ 1145 int i, n; 1146 const unsigned char *pBlob; 1147 char *zHex, *z; 1148 assert( argc==1 ); 1149 UNUSED_PARAMETER(argc); 1150 pBlob = sqlite3_value_blob(argv[0]); 1151 n = sqlite3_value_bytes(argv[0]); 1152 assert( pBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */ 1153 z = zHex = contextMalloc(context, ((i64)n)*2 + 1); 1154 if( zHex ){ 1155 for(i=0; i<n; i++, pBlob++){ 1156 unsigned char c = *pBlob; 1157 *(z++) = hexdigits[(c>>4)&0xf]; 1158 *(z++) = hexdigits[c&0xf]; 1159 } 1160 *z = 0; 1161 sqlite3_result_text(context, zHex, n*2, sqlite3_free); 1162 } 1163 } 1164 1165 /* 1166 ** The zeroblob(N) function returns a zero-filled blob of size N bytes. 1167 */ 1168 static void zeroblobFunc( 1169 sqlite3_context *context, 1170 int argc, 1171 sqlite3_value **argv 1172 ){ 1173 i64 n; 1174 int rc; 1175 assert( argc==1 ); 1176 UNUSED_PARAMETER(argc); 1177 n = sqlite3_value_int64(argv[0]); 1178 if( n<0 ) n = 0; 1179 rc = sqlite3_result_zeroblob64(context, n); /* IMP: R-00293-64994 */ 1180 if( rc ){ 1181 sqlite3_result_error_code(context, rc); 1182 } 1183 } 1184 1185 /* 1186 ** The replace() function. Three arguments are all strings: call 1187 ** them A, B, and C. The result is also a string which is derived 1188 ** from A by replacing every occurrence of B with C. The match 1189 ** must be exact. Collating sequences are not used. 1190 */ 1191 static void replaceFunc( 1192 sqlite3_context *context, 1193 int argc, 1194 sqlite3_value **argv 1195 ){ 1196 const unsigned char *zStr; /* The input string A */ 1197 const unsigned char *zPattern; /* The pattern string B */ 1198 const unsigned char *zRep; /* The replacement string C */ 1199 unsigned char *zOut; /* The output */ 1200 int nStr; /* Size of zStr */ 1201 int nPattern; /* Size of zPattern */ 1202 int nRep; /* Size of zRep */ 1203 i64 nOut; /* Maximum size of zOut */ 1204 int loopLimit; /* Last zStr[] that might match zPattern[] */ 1205 int i, j; /* Loop counters */ 1206 unsigned cntExpand; /* Number zOut expansions */ 1207 sqlite3 *db = sqlite3_context_db_handle(context); 1208 1209 assert( argc==3 ); 1210 UNUSED_PARAMETER(argc); 1211 zStr = sqlite3_value_text(argv[0]); 1212 if( zStr==0 ) return; 1213 nStr = sqlite3_value_bytes(argv[0]); 1214 assert( zStr==sqlite3_value_text(argv[0]) ); /* No encoding change */ 1215 zPattern = sqlite3_value_text(argv[1]); 1216 if( zPattern==0 ){ 1217 assert( sqlite3_value_type(argv[1])==SQLITE_NULL 1218 || sqlite3_context_db_handle(context)->mallocFailed ); 1219 return; 1220 } 1221 if( zPattern[0]==0 ){ 1222 assert( sqlite3_value_type(argv[1])!=SQLITE_NULL ); 1223 sqlite3_result_value(context, argv[0]); 1224 return; 1225 } 1226 nPattern = sqlite3_value_bytes(argv[1]); 1227 assert( zPattern==sqlite3_value_text(argv[1]) ); /* No encoding change */ 1228 zRep = sqlite3_value_text(argv[2]); 1229 if( zRep==0 ) return; 1230 nRep = sqlite3_value_bytes(argv[2]); 1231 assert( zRep==sqlite3_value_text(argv[2]) ); 1232 nOut = nStr + 1; 1233 assert( nOut<SQLITE_MAX_LENGTH ); 1234 zOut = contextMalloc(context, (i64)nOut); 1235 if( zOut==0 ){ 1236 return; 1237 } 1238 loopLimit = nStr - nPattern; 1239 cntExpand = 0; 1240 for(i=j=0; i<=loopLimit; i++){ 1241 if( zStr[i]!=zPattern[0] || memcmp(&zStr[i], zPattern, nPattern) ){ 1242 zOut[j++] = zStr[i]; 1243 }else{ 1244 if( nRep>nPattern ){ 1245 nOut += nRep - nPattern; 1246 testcase( nOut-1==db->aLimit[SQLITE_LIMIT_LENGTH] ); 1247 testcase( nOut-2==db->aLimit[SQLITE_LIMIT_LENGTH] ); 1248 if( nOut-1>db->aLimit[SQLITE_LIMIT_LENGTH] ){ 1249 sqlite3_result_error_toobig(context); 1250 sqlite3_free(zOut); 1251 return; 1252 } 1253 cntExpand++; 1254 if( (cntExpand&(cntExpand-1))==0 ){ 1255 /* Grow the size of the output buffer only on substitutions 1256 ** whose index is a power of two: 1, 2, 4, 8, 16, 32, ... */ 1257 u8 *zOld; 1258 zOld = zOut; 1259 zOut = sqlite3_realloc64(zOut, (int)nOut + (nOut - nStr - 1)); 1260 if( zOut==0 ){ 1261 sqlite3_result_error_nomem(context); 1262 sqlite3_free(zOld); 1263 return; 1264 } 1265 } 1266 } 1267 memcpy(&zOut[j], zRep, nRep); 1268 j += nRep; 1269 i += nPattern-1; 1270 } 1271 } 1272 assert( j+nStr-i+1<=nOut ); 1273 memcpy(&zOut[j], &zStr[i], nStr-i); 1274 j += nStr - i; 1275 assert( j<=nOut ); 1276 zOut[j] = 0; 1277 sqlite3_result_text(context, (char*)zOut, j, sqlite3_free); 1278 } 1279 1280 /* 1281 ** Implementation of the TRIM(), LTRIM(), and RTRIM() functions. 1282 ** The userdata is 0x1 for left trim, 0x2 for right trim, 0x3 for both. 1283 */ 1284 static void trimFunc( 1285 sqlite3_context *context, 1286 int argc, 1287 sqlite3_value **argv 1288 ){ 1289 const unsigned char *zIn; /* Input string */ 1290 const unsigned char *zCharSet; /* Set of characters to trim */ 1291 int nIn; /* Number of bytes in input */ 1292 int flags; /* 1: trimleft 2: trimright 3: trim */ 1293 int i; /* Loop counter */ 1294 unsigned char *aLen = 0; /* Length of each character in zCharSet */ 1295 unsigned char **azChar = 0; /* Individual characters in zCharSet */ 1296 int nChar; /* Number of characters in zCharSet */ 1297 1298 if( sqlite3_value_type(argv[0])==SQLITE_NULL ){ 1299 return; 1300 } 1301 zIn = sqlite3_value_text(argv[0]); 1302 if( zIn==0 ) return; 1303 nIn = sqlite3_value_bytes(argv[0]); 1304 assert( zIn==sqlite3_value_text(argv[0]) ); 1305 if( argc==1 ){ 1306 static const unsigned char lenOne[] = { 1 }; 1307 static unsigned char * const azOne[] = { (u8*)" " }; 1308 nChar = 1; 1309 aLen = (u8*)lenOne; 1310 azChar = (unsigned char **)azOne; 1311 zCharSet = 0; 1312 }else if( (zCharSet = sqlite3_value_text(argv[1]))==0 ){ 1313 return; 1314 }else{ 1315 const unsigned char *z; 1316 for(z=zCharSet, nChar=0; *z; nChar++){ 1317 SQLITE_SKIP_UTF8(z); 1318 } 1319 if( nChar>0 ){ 1320 azChar = contextMalloc(context, ((i64)nChar)*(sizeof(char*)+1)); 1321 if( azChar==0 ){ 1322 return; 1323 } 1324 aLen = (unsigned char*)&azChar[nChar]; 1325 for(z=zCharSet, nChar=0; *z; nChar++){ 1326 azChar[nChar] = (unsigned char *)z; 1327 SQLITE_SKIP_UTF8(z); 1328 aLen[nChar] = (u8)(z - azChar[nChar]); 1329 } 1330 } 1331 } 1332 if( nChar>0 ){ 1333 flags = SQLITE_PTR_TO_INT(sqlite3_user_data(context)); 1334 if( flags & 1 ){ 1335 while( nIn>0 ){ 1336 int len = 0; 1337 for(i=0; i<nChar; i++){ 1338 len = aLen[i]; 1339 if( len<=nIn && memcmp(zIn, azChar[i], len)==0 ) break; 1340 } 1341 if( i>=nChar ) break; 1342 zIn += len; 1343 nIn -= len; 1344 } 1345 } 1346 if( flags & 2 ){ 1347 while( nIn>0 ){ 1348 int len = 0; 1349 for(i=0; i<nChar; i++){ 1350 len = aLen[i]; 1351 if( len<=nIn && memcmp(&zIn[nIn-len],azChar[i],len)==0 ) break; 1352 } 1353 if( i>=nChar ) break; 1354 nIn -= len; 1355 } 1356 } 1357 if( zCharSet ){ 1358 sqlite3_free(azChar); 1359 } 1360 } 1361 sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT); 1362 } 1363 1364 1365 #ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION 1366 /* 1367 ** The "unknown" function is automatically substituted in place of 1368 ** any unrecognized function name when doing an EXPLAIN or EXPLAIN QUERY PLAN 1369 ** when the SQLITE_ENABLE_UNKNOWN_FUNCTION compile-time option is used. 1370 ** When the "sqlite3" command-line shell is built using this functionality, 1371 ** that allows an EXPLAIN or EXPLAIN QUERY PLAN for complex queries 1372 ** involving application-defined functions to be examined in a generic 1373 ** sqlite3 shell. 1374 */ 1375 static void unknownFunc( 1376 sqlite3_context *context, 1377 int argc, 1378 sqlite3_value **argv 1379 ){ 1380 /* no-op */ 1381 } 1382 #endif /*SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION*/ 1383 1384 1385 /* IMP: R-25361-16150 This function is omitted from SQLite by default. It 1386 ** is only available if the SQLITE_SOUNDEX compile-time option is used 1387 ** when SQLite is built. 1388 */ 1389 #ifdef SQLITE_SOUNDEX 1390 /* 1391 ** Compute the soundex encoding of a word. 1392 ** 1393 ** IMP: R-59782-00072 The soundex(X) function returns a string that is the 1394 ** soundex encoding of the string X. 1395 */ 1396 static void soundexFunc( 1397 sqlite3_context *context, 1398 int argc, 1399 sqlite3_value **argv 1400 ){ 1401 char zResult[8]; 1402 const u8 *zIn; 1403 int i, j; 1404 static const unsigned char iCode[] = { 1405 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1406 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1407 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1408 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1409 0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0, 1410 1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0, 1411 0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0, 1412 1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0, 1413 }; 1414 assert( argc==1 ); 1415 zIn = (u8*)sqlite3_value_text(argv[0]); 1416 if( zIn==0 ) zIn = (u8*)""; 1417 for(i=0; zIn[i] && !sqlite3Isalpha(zIn[i]); i++){} 1418 if( zIn[i] ){ 1419 u8 prevcode = iCode[zIn[i]&0x7f]; 1420 zResult[0] = sqlite3Toupper(zIn[i]); 1421 for(j=1; j<4 && zIn[i]; i++){ 1422 int code = iCode[zIn[i]&0x7f]; 1423 if( code>0 ){ 1424 if( code!=prevcode ){ 1425 prevcode = code; 1426 zResult[j++] = code + '0'; 1427 } 1428 }else{ 1429 prevcode = 0; 1430 } 1431 } 1432 while( j<4 ){ 1433 zResult[j++] = '0'; 1434 } 1435 zResult[j] = 0; 1436 sqlite3_result_text(context, zResult, 4, SQLITE_TRANSIENT); 1437 }else{ 1438 /* IMP: R-64894-50321 The string "?000" is returned if the argument 1439 ** is NULL or contains no ASCII alphabetic characters. */ 1440 sqlite3_result_text(context, "?000", 4, SQLITE_STATIC); 1441 } 1442 } 1443 #endif /* SQLITE_SOUNDEX */ 1444 1445 #ifndef SQLITE_OMIT_LOAD_EXTENSION 1446 /* 1447 ** A function that loads a shared-library extension then returns NULL. 1448 */ 1449 static void loadExt(sqlite3_context *context, int argc, sqlite3_value **argv){ 1450 const char *zFile = (const char *)sqlite3_value_text(argv[0]); 1451 const char *zProc; 1452 sqlite3 *db = sqlite3_context_db_handle(context); 1453 char *zErrMsg = 0; 1454 1455 /* Disallow the load_extension() SQL function unless the SQLITE_LoadExtFunc 1456 ** flag is set. See the sqlite3_enable_load_extension() API. 1457 */ 1458 if( (db->flags & SQLITE_LoadExtFunc)==0 ){ 1459 sqlite3_result_error(context, "not authorized", -1); 1460 return; 1461 } 1462 1463 if( argc==2 ){ 1464 zProc = (const char *)sqlite3_value_text(argv[1]); 1465 }else{ 1466 zProc = 0; 1467 } 1468 if( zFile && sqlite3_load_extension(db, zFile, zProc, &zErrMsg) ){ 1469 sqlite3_result_error(context, zErrMsg, -1); 1470 sqlite3_free(zErrMsg); 1471 } 1472 } 1473 #endif 1474 1475 1476 /* 1477 ** An instance of the following structure holds the context of a 1478 ** sum() or avg() aggregate computation. 1479 */ 1480 typedef struct SumCtx SumCtx; 1481 struct SumCtx { 1482 double rSum; /* Floating point sum */ 1483 i64 iSum; /* Integer sum */ 1484 i64 cnt; /* Number of elements summed */ 1485 u8 overflow; /* True if integer overflow seen */ 1486 u8 approx; /* True if non-integer value was input to the sum */ 1487 }; 1488 1489 /* 1490 ** Routines used to compute the sum, average, and total. 1491 ** 1492 ** The SUM() function follows the (broken) SQL standard which means 1493 ** that it returns NULL if it sums over no inputs. TOTAL returns 1494 ** 0.0 in that case. In addition, TOTAL always returns a float where 1495 ** SUM might return an integer if it never encounters a floating point 1496 ** value. TOTAL never fails, but SUM might through an exception if 1497 ** it overflows an integer. 1498 */ 1499 static void sumStep(sqlite3_context *context, int argc, sqlite3_value **argv){ 1500 SumCtx *p; 1501 int type; 1502 assert( argc==1 ); 1503 UNUSED_PARAMETER(argc); 1504 p = sqlite3_aggregate_context(context, sizeof(*p)); 1505 type = sqlite3_value_numeric_type(argv[0]); 1506 if( p && type!=SQLITE_NULL ){ 1507 p->cnt++; 1508 if( type==SQLITE_INTEGER ){ 1509 i64 v = sqlite3_value_int64(argv[0]); 1510 p->rSum += v; 1511 if( (p->approx|p->overflow)==0 && sqlite3AddInt64(&p->iSum, v) ){ 1512 p->approx = p->overflow = 1; 1513 } 1514 }else{ 1515 p->rSum += sqlite3_value_double(argv[0]); 1516 p->approx = 1; 1517 } 1518 } 1519 } 1520 #ifndef SQLITE_OMIT_WINDOWFUNC 1521 static void sumInverse(sqlite3_context *context, int argc, sqlite3_value**argv){ 1522 SumCtx *p; 1523 int type; 1524 assert( argc==1 ); 1525 UNUSED_PARAMETER(argc); 1526 p = sqlite3_aggregate_context(context, sizeof(*p)); 1527 type = sqlite3_value_numeric_type(argv[0]); 1528 /* p is always non-NULL because sumStep() will have been called first 1529 ** to initialize it */ 1530 if( ALWAYS(p) && type!=SQLITE_NULL ){ 1531 assert( p->cnt>0 ); 1532 p->cnt--; 1533 assert( type==SQLITE_INTEGER || p->approx ); 1534 if( type==SQLITE_INTEGER && p->approx==0 ){ 1535 i64 v = sqlite3_value_int64(argv[0]); 1536 p->rSum -= v; 1537 p->iSum -= v; 1538 }else{ 1539 p->rSum -= sqlite3_value_double(argv[0]); 1540 } 1541 } 1542 } 1543 #else 1544 # define sumInverse 0 1545 #endif /* SQLITE_OMIT_WINDOWFUNC */ 1546 static void sumFinalize(sqlite3_context *context){ 1547 SumCtx *p; 1548 p = sqlite3_aggregate_context(context, 0); 1549 if( p && p->cnt>0 ){ 1550 if( p->overflow ){ 1551 sqlite3_result_error(context,"integer overflow",-1); 1552 }else if( p->approx ){ 1553 sqlite3_result_double(context, p->rSum); 1554 }else{ 1555 sqlite3_result_int64(context, p->iSum); 1556 } 1557 } 1558 } 1559 static void avgFinalize(sqlite3_context *context){ 1560 SumCtx *p; 1561 p = sqlite3_aggregate_context(context, 0); 1562 if( p && p->cnt>0 ){ 1563 sqlite3_result_double(context, p->rSum/(double)p->cnt); 1564 } 1565 } 1566 static void totalFinalize(sqlite3_context *context){ 1567 SumCtx *p; 1568 p = sqlite3_aggregate_context(context, 0); 1569 /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */ 1570 sqlite3_result_double(context, p ? p->rSum : (double)0); 1571 } 1572 1573 /* 1574 ** The following structure keeps track of state information for the 1575 ** count() aggregate function. 1576 */ 1577 typedef struct CountCtx CountCtx; 1578 struct CountCtx { 1579 i64 n; 1580 #ifdef SQLITE_DEBUG 1581 int bInverse; /* True if xInverse() ever called */ 1582 #endif 1583 }; 1584 1585 /* 1586 ** Routines to implement the count() aggregate function. 1587 */ 1588 static void countStep(sqlite3_context *context, int argc, sqlite3_value **argv){ 1589 CountCtx *p; 1590 p = sqlite3_aggregate_context(context, sizeof(*p)); 1591 if( (argc==0 || SQLITE_NULL!=sqlite3_value_type(argv[0])) && p ){ 1592 p->n++; 1593 } 1594 1595 #ifndef SQLITE_OMIT_DEPRECATED 1596 /* The sqlite3_aggregate_count() function is deprecated. But just to make 1597 ** sure it still operates correctly, verify that its count agrees with our 1598 ** internal count when using count(*) and when the total count can be 1599 ** expressed as a 32-bit integer. */ 1600 assert( argc==1 || p==0 || p->n>0x7fffffff || p->bInverse 1601 || p->n==sqlite3_aggregate_count(context) ); 1602 #endif 1603 } 1604 static void countFinalize(sqlite3_context *context){ 1605 CountCtx *p; 1606 p = sqlite3_aggregate_context(context, 0); 1607 sqlite3_result_int64(context, p ? p->n : 0); 1608 } 1609 #ifndef SQLITE_OMIT_WINDOWFUNC 1610 static void countInverse(sqlite3_context *ctx, int argc, sqlite3_value **argv){ 1611 CountCtx *p; 1612 p = sqlite3_aggregate_context(ctx, sizeof(*p)); 1613 /* p is always non-NULL since countStep() will have been called first */ 1614 if( (argc==0 || SQLITE_NULL!=sqlite3_value_type(argv[0])) && ALWAYS(p) ){ 1615 p->n--; 1616 #ifdef SQLITE_DEBUG 1617 p->bInverse = 1; 1618 #endif 1619 } 1620 } 1621 #else 1622 # define countInverse 0 1623 #endif /* SQLITE_OMIT_WINDOWFUNC */ 1624 1625 /* 1626 ** Routines to implement min() and max() aggregate functions. 1627 */ 1628 static void minmaxStep( 1629 sqlite3_context *context, 1630 int NotUsed, 1631 sqlite3_value **argv 1632 ){ 1633 Mem *pArg = (Mem *)argv[0]; 1634 Mem *pBest; 1635 UNUSED_PARAMETER(NotUsed); 1636 1637 pBest = (Mem *)sqlite3_aggregate_context(context, sizeof(*pBest)); 1638 if( !pBest ) return; 1639 1640 if( sqlite3_value_type(pArg)==SQLITE_NULL ){ 1641 if( pBest->flags ) sqlite3SkipAccumulatorLoad(context); 1642 }else if( pBest->flags ){ 1643 int max; 1644 int cmp; 1645 CollSeq *pColl = sqlite3GetFuncCollSeq(context); 1646 /* This step function is used for both the min() and max() aggregates, 1647 ** the only difference between the two being that the sense of the 1648 ** comparison is inverted. For the max() aggregate, the 1649 ** sqlite3_user_data() function returns (void *)-1. For min() it 1650 ** returns (void *)db, where db is the sqlite3* database pointer. 1651 ** Therefore the next statement sets variable 'max' to 1 for the max() 1652 ** aggregate, or 0 for min(). 1653 */ 1654 max = sqlite3_user_data(context)!=0; 1655 cmp = sqlite3MemCompare(pBest, pArg, pColl); 1656 if( (max && cmp<0) || (!max && cmp>0) ){ 1657 sqlite3VdbeMemCopy(pBest, pArg); 1658 }else{ 1659 sqlite3SkipAccumulatorLoad(context); 1660 } 1661 }else{ 1662 pBest->db = sqlite3_context_db_handle(context); 1663 sqlite3VdbeMemCopy(pBest, pArg); 1664 } 1665 } 1666 static void minMaxValueFinalize(sqlite3_context *context, int bValue){ 1667 sqlite3_value *pRes; 1668 pRes = (sqlite3_value *)sqlite3_aggregate_context(context, 0); 1669 if( pRes ){ 1670 if( pRes->flags ){ 1671 sqlite3_result_value(context, pRes); 1672 } 1673 if( bValue==0 ) sqlite3VdbeMemRelease(pRes); 1674 } 1675 } 1676 #ifndef SQLITE_OMIT_WINDOWFUNC 1677 static void minMaxValue(sqlite3_context *context){ 1678 minMaxValueFinalize(context, 1); 1679 } 1680 #else 1681 # define minMaxValue 0 1682 #endif /* SQLITE_OMIT_WINDOWFUNC */ 1683 static void minMaxFinalize(sqlite3_context *context){ 1684 minMaxValueFinalize(context, 0); 1685 } 1686 1687 /* 1688 ** group_concat(EXPR, ?SEPARATOR?) 1689 */ 1690 static void groupConcatStep( 1691 sqlite3_context *context, 1692 int argc, 1693 sqlite3_value **argv 1694 ){ 1695 const char *zVal; 1696 StrAccum *pAccum; 1697 const char *zSep; 1698 int nVal, nSep; 1699 assert( argc==1 || argc==2 ); 1700 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; 1701 pAccum = (StrAccum*)sqlite3_aggregate_context(context, sizeof(*pAccum)); 1702 1703 if( pAccum ){ 1704 sqlite3 *db = sqlite3_context_db_handle(context); 1705 int firstTerm = pAccum->mxAlloc==0; 1706 pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH]; 1707 if( !firstTerm ){ 1708 if( argc==2 ){ 1709 zSep = (char*)sqlite3_value_text(argv[1]); 1710 nSep = sqlite3_value_bytes(argv[1]); 1711 }else{ 1712 zSep = ","; 1713 nSep = 1; 1714 } 1715 if( zSep ) sqlite3_str_append(pAccum, zSep, nSep); 1716 } 1717 zVal = (char*)sqlite3_value_text(argv[0]); 1718 nVal = sqlite3_value_bytes(argv[0]); 1719 if( zVal ) sqlite3_str_append(pAccum, zVal, nVal); 1720 } 1721 } 1722 #ifndef SQLITE_OMIT_WINDOWFUNC 1723 static void groupConcatInverse( 1724 sqlite3_context *context, 1725 int argc, 1726 sqlite3_value **argv 1727 ){ 1728 int n; 1729 StrAccum *pAccum; 1730 assert( argc==1 || argc==2 ); 1731 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; 1732 pAccum = (StrAccum*)sqlite3_aggregate_context(context, sizeof(*pAccum)); 1733 /* pAccum is always non-NULL since groupConcatStep() will have always 1734 ** run frist to initialize it */ 1735 if( ALWAYS(pAccum) ){ 1736 n = sqlite3_value_bytes(argv[0]); 1737 if( argc==2 ){ 1738 n += sqlite3_value_bytes(argv[1]); 1739 }else{ 1740 n++; 1741 } 1742 if( n>=(int)pAccum->nChar ){ 1743 pAccum->nChar = 0; 1744 }else{ 1745 pAccum->nChar -= n; 1746 memmove(pAccum->zText, &pAccum->zText[n], pAccum->nChar); 1747 } 1748 if( pAccum->nChar==0 ) pAccum->mxAlloc = 0; 1749 } 1750 } 1751 #else 1752 # define groupConcatInverse 0 1753 #endif /* SQLITE_OMIT_WINDOWFUNC */ 1754 static void groupConcatFinalize(sqlite3_context *context){ 1755 StrAccum *pAccum; 1756 pAccum = sqlite3_aggregate_context(context, 0); 1757 if( pAccum ){ 1758 if( pAccum->accError==SQLITE_TOOBIG ){ 1759 sqlite3_result_error_toobig(context); 1760 }else if( pAccum->accError==SQLITE_NOMEM ){ 1761 sqlite3_result_error_nomem(context); 1762 }else{ 1763 sqlite3_result_text(context, sqlite3StrAccumFinish(pAccum), -1, 1764 sqlite3_free); 1765 } 1766 } 1767 } 1768 #ifndef SQLITE_OMIT_WINDOWFUNC 1769 static void groupConcatValue(sqlite3_context *context){ 1770 sqlite3_str *pAccum; 1771 pAccum = (sqlite3_str*)sqlite3_aggregate_context(context, 0); 1772 if( pAccum ){ 1773 if( pAccum->accError==SQLITE_TOOBIG ){ 1774 sqlite3_result_error_toobig(context); 1775 }else if( pAccum->accError==SQLITE_NOMEM ){ 1776 sqlite3_result_error_nomem(context); 1777 }else{ 1778 const char *zText = sqlite3_str_value(pAccum); 1779 sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT); 1780 } 1781 } 1782 } 1783 #else 1784 # define groupConcatValue 0 1785 #endif /* SQLITE_OMIT_WINDOWFUNC */ 1786 1787 /* 1788 ** This routine does per-connection function registration. Most 1789 ** of the built-in functions above are part of the global function set. 1790 ** This routine only deals with those that are not global. 1791 */ 1792 void sqlite3RegisterPerConnectionBuiltinFunctions(sqlite3 *db){ 1793 int rc = sqlite3_overload_function(db, "MATCH", 2); 1794 assert( rc==SQLITE_NOMEM || rc==SQLITE_OK ); 1795 if( rc==SQLITE_NOMEM ){ 1796 sqlite3OomFault(db); 1797 } 1798 } 1799 1800 /* 1801 ** Set the LIKEOPT flag on the 2-argument function with the given name. 1802 */ 1803 static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){ 1804 FuncDef *pDef; 1805 pDef = sqlite3FindFunction(db, zName, 2, SQLITE_UTF8, 0); 1806 if( ALWAYS(pDef) ){ 1807 pDef->funcFlags |= flagVal; 1808 } 1809 pDef = sqlite3FindFunction(db, zName, 3, SQLITE_UTF8, 0); 1810 if( pDef ){ 1811 pDef->funcFlags |= flagVal; 1812 } 1813 } 1814 1815 /* 1816 ** Register the built-in LIKE and GLOB functions. The caseSensitive 1817 ** parameter determines whether or not the LIKE operator is case 1818 ** sensitive. GLOB is always case sensitive. 1819 */ 1820 void sqlite3RegisterLikeFunctions(sqlite3 *db, int caseSensitive){ 1821 struct compareInfo *pInfo; 1822 if( caseSensitive ){ 1823 pInfo = (struct compareInfo*)&likeInfoAlt; 1824 }else{ 1825 pInfo = (struct compareInfo*)&likeInfoNorm; 1826 } 1827 sqlite3CreateFunc(db, "like", 2, SQLITE_UTF8, pInfo, likeFunc, 0, 0, 0, 0, 0); 1828 sqlite3CreateFunc(db, "like", 3, SQLITE_UTF8, pInfo, likeFunc, 0, 0, 0, 0, 0); 1829 sqlite3CreateFunc(db, "glob", 2, SQLITE_UTF8, 1830 (struct compareInfo*)&globInfo, likeFunc, 0, 0, 0, 0, 0); 1831 setLikeOptFlag(db, "glob", SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE); 1832 setLikeOptFlag(db, "like", 1833 caseSensitive ? (SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE) : SQLITE_FUNC_LIKE); 1834 } 1835 1836 /* 1837 ** pExpr points to an expression which implements a function. If 1838 ** it is appropriate to apply the LIKE optimization to that function 1839 ** then set aWc[0] through aWc[2] to the wildcard characters and the 1840 ** escape character and then return TRUE. If the function is not a 1841 ** LIKE-style function then return FALSE. 1842 ** 1843 ** The expression "a LIKE b ESCAPE c" is only considered a valid LIKE 1844 ** operator if c is a string literal that is exactly one byte in length. 1845 ** That one byte is stored in aWc[3]. aWc[3] is set to zero if there is 1846 ** no ESCAPE clause. 1847 ** 1848 ** *pIsNocase is set to true if uppercase and lowercase are equivalent for 1849 ** the function (default for LIKE). If the function makes the distinction 1850 ** between uppercase and lowercase (as does GLOB) then *pIsNocase is set to 1851 ** false. 1852 */ 1853 int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){ 1854 FuncDef *pDef; 1855 int nExpr; 1856 if( pExpr->op!=TK_FUNCTION || !pExpr->x.pList ){ 1857 return 0; 1858 } 1859 assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); 1860 nExpr = pExpr->x.pList->nExpr; 1861 pDef = sqlite3FindFunction(db, pExpr->u.zToken, nExpr, SQLITE_UTF8, 0); 1862 if( NEVER(pDef==0) || (pDef->funcFlags & SQLITE_FUNC_LIKE)==0 ){ 1863 return 0; 1864 } 1865 if( nExpr<3 ){ 1866 aWc[3] = 0; 1867 }else{ 1868 Expr *pEscape = pExpr->x.pList->a[2].pExpr; 1869 char *zEscape; 1870 if( pEscape->op!=TK_STRING ) return 0; 1871 zEscape = pEscape->u.zToken; 1872 if( zEscape[0]==0 || zEscape[1]!=0 ) return 0; 1873 aWc[3] = zEscape[0]; 1874 } 1875 1876 /* The memcpy() statement assumes that the wildcard characters are 1877 ** the first three statements in the compareInfo structure. The 1878 ** asserts() that follow verify that assumption 1879 */ 1880 memcpy(aWc, pDef->pUserData, 3); 1881 assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll ); 1882 assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne ); 1883 assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet ); 1884 *pIsNocase = (pDef->funcFlags & SQLITE_FUNC_CASE)==0; 1885 return 1; 1886 } 1887 1888 /* 1889 ** All of the FuncDef structures in the aBuiltinFunc[] array above 1890 ** to the global function hash table. This occurs at start-time (as 1891 ** a consequence of calling sqlite3_initialize()). 1892 ** 1893 ** After this routine runs 1894 */ 1895 void sqlite3RegisterBuiltinFunctions(void){ 1896 /* 1897 ** The following array holds FuncDef structures for all of the functions 1898 ** defined in this file. 1899 ** 1900 ** The array cannot be constant since changes are made to the 1901 ** FuncDef.pHash elements at start-time. The elements of this array 1902 ** are read-only after initialization is complete. 1903 ** 1904 ** For peak efficiency, put the most frequently used function last. 1905 */ 1906 static FuncDef aBuiltinFunc[] = { 1907 #ifdef SQLITE_SOUNDEX 1908 FUNCTION(soundex, 1, 0, 0, soundexFunc ), 1909 #endif 1910 #ifndef SQLITE_OMIT_LOAD_EXTENSION 1911 VFUNCTION(load_extension, 1, 0, 0, loadExt ), 1912 VFUNCTION(load_extension, 2, 0, 0, loadExt ), 1913 #endif 1914 #if SQLITE_USER_AUTHENTICATION 1915 FUNCTION(sqlite_crypt, 2, 0, 0, sqlite3CryptFunc ), 1916 #endif 1917 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 1918 DFUNCTION(sqlite_compileoption_used,1, 0, 0, compileoptionusedFunc ), 1919 DFUNCTION(sqlite_compileoption_get, 1, 0, 0, compileoptiongetFunc ), 1920 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ 1921 FUNCTION2(unlikely, 1, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), 1922 FUNCTION2(likelihood, 2, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), 1923 FUNCTION2(likely, 1, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), 1924 #ifdef SQLITE_DEBUG 1925 FUNCTION2(affinity, 1, 0, 0, noopFunc, SQLITE_FUNC_AFFINITY), 1926 #endif 1927 #ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC 1928 FUNCTION2(sqlite_offset, 1, 0, 0, noopFunc, SQLITE_FUNC_OFFSET| 1929 SQLITE_FUNC_TYPEOF), 1930 #endif 1931 FUNCTION(ltrim, 1, 1, 0, trimFunc ), 1932 FUNCTION(ltrim, 2, 1, 0, trimFunc ), 1933 FUNCTION(rtrim, 1, 2, 0, trimFunc ), 1934 FUNCTION(rtrim, 2, 2, 0, trimFunc ), 1935 FUNCTION(trim, 1, 3, 0, trimFunc ), 1936 FUNCTION(trim, 2, 3, 0, trimFunc ), 1937 FUNCTION(min, -1, 0, 1, minmaxFunc ), 1938 FUNCTION(min, 0, 0, 1, 0 ), 1939 WAGGREGATE(min, 1, 0, 1, minmaxStep, minMaxFinalize, minMaxValue, 0, 1940 SQLITE_FUNC_MINMAX ), 1941 FUNCTION(max, -1, 1, 1, minmaxFunc ), 1942 FUNCTION(max, 0, 1, 1, 0 ), 1943 WAGGREGATE(max, 1, 1, 1, minmaxStep, minMaxFinalize, minMaxValue, 0, 1944 SQLITE_FUNC_MINMAX ), 1945 FUNCTION2(typeof, 1, 0, 0, typeofFunc, SQLITE_FUNC_TYPEOF), 1946 FUNCTION2(length, 1, 0, 0, lengthFunc, SQLITE_FUNC_LENGTH), 1947 FUNCTION(instr, 2, 0, 0, instrFunc ), 1948 FUNCTION(printf, -1, 0, 0, printfFunc ), 1949 FUNCTION(unicode, 1, 0, 0, unicodeFunc ), 1950 FUNCTION(char, -1, 0, 0, charFunc ), 1951 FUNCTION(abs, 1, 0, 0, absFunc ), 1952 #ifndef SQLITE_OMIT_FLOATING_POINT 1953 FUNCTION(round, 1, 0, 0, roundFunc ), 1954 FUNCTION(round, 2, 0, 0, roundFunc ), 1955 #endif 1956 FUNCTION(upper, 1, 0, 0, upperFunc ), 1957 FUNCTION(lower, 1, 0, 0, lowerFunc ), 1958 FUNCTION(hex, 1, 0, 0, hexFunc ), 1959 FUNCTION2(ifnull, 2, 0, 0, noopFunc, SQLITE_FUNC_COALESCE), 1960 VFUNCTION(random, 0, 0, 0, randomFunc ), 1961 VFUNCTION(randomblob, 1, 0, 0, randomBlob ), 1962 FUNCTION(nullif, 2, 0, 1, nullifFunc ), 1963 DFUNCTION(sqlite_version, 0, 0, 0, versionFunc ), 1964 DFUNCTION(sqlite_source_id, 0, 0, 0, sourceidFunc ), 1965 FUNCTION(sqlite_log, 2, 0, 0, errlogFunc ), 1966 FUNCTION(quote, 1, 0, 0, quoteFunc ), 1967 VFUNCTION(last_insert_rowid, 0, 0, 0, last_insert_rowid), 1968 VFUNCTION(changes, 0, 0, 0, changes ), 1969 VFUNCTION(total_changes, 0, 0, 0, total_changes ), 1970 FUNCTION(replace, 3, 0, 0, replaceFunc ), 1971 FUNCTION(zeroblob, 1, 0, 0, zeroblobFunc ), 1972 FUNCTION(substr, 2, 0, 0, substrFunc ), 1973 FUNCTION(substr, 3, 0, 0, substrFunc ), 1974 WAGGREGATE(sum, 1,0,0, sumStep, sumFinalize, sumFinalize, sumInverse, 0), 1975 WAGGREGATE(total, 1,0,0, sumStep,totalFinalize,totalFinalize,sumInverse, 0), 1976 WAGGREGATE(avg, 1,0,0, sumStep, avgFinalize, avgFinalize, sumInverse, 0), 1977 WAGGREGATE(count, 0,0,0, countStep, 1978 countFinalize, countFinalize, countInverse, SQLITE_FUNC_COUNT ), 1979 WAGGREGATE(count, 1,0,0, countStep, 1980 countFinalize, countFinalize, countInverse, 0 ), 1981 WAGGREGATE(group_concat, 1, 0, 0, groupConcatStep, 1982 groupConcatFinalize, groupConcatValue, groupConcatInverse, 0), 1983 WAGGREGATE(group_concat, 2, 0, 0, groupConcatStep, 1984 groupConcatFinalize, groupConcatValue, groupConcatInverse, 0), 1985 1986 LIKEFUNC(glob, 2, &globInfo, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), 1987 #ifdef SQLITE_CASE_SENSITIVE_LIKE 1988 LIKEFUNC(like, 2, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), 1989 LIKEFUNC(like, 3, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), 1990 #else 1991 LIKEFUNC(like, 2, &likeInfoNorm, SQLITE_FUNC_LIKE), 1992 LIKEFUNC(like, 3, &likeInfoNorm, SQLITE_FUNC_LIKE), 1993 #endif 1994 #ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION 1995 FUNCTION(unknown, -1, 0, 0, unknownFunc ), 1996 #endif 1997 FUNCTION(coalesce, 1, 0, 0, 0 ), 1998 FUNCTION(coalesce, 0, 0, 0, 0 ), 1999 FUNCTION2(coalesce, -1, 0, 0, noopFunc, SQLITE_FUNC_COALESCE), 2000 }; 2001 #ifndef SQLITE_OMIT_ALTERTABLE 2002 sqlite3AlterFunctions(); 2003 #endif 2004 sqlite3WindowFunctions(); 2005 #if defined(SQLITE_ENABLE_STAT3) || defined(SQLITE_ENABLE_STAT4) 2006 sqlite3AnalyzeFunctions(); 2007 #endif 2008 sqlite3RegisterDateTimeFunctions(); 2009 sqlite3InsertBuiltinFuncs(aBuiltinFunc, ArraySize(aBuiltinFunc)); 2010 2011 #if 0 /* Enable to print out how the built-in functions are hashed */ 2012 { 2013 int i; 2014 FuncDef *p; 2015 for(i=0; i<SQLITE_FUNC_HASH_SZ; i++){ 2016 printf("FUNC-HASH %02d:", i); 2017 for(p=sqlite3BuiltinFunctions.a[i]; p; p=p->u.pHash){ 2018 int n = sqlite3Strlen30(p->zName); 2019 int h = p->zName[0] + n; 2020 printf(" %s(%d)", p->zName, h); 2021 } 2022 printf("\n"); 2023 } 2024 } 2025 #endif 2026 } 2027