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| 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 context->skipFlag = 1; |
| 39 } |
| 40 |
| 41 /* |
| 42 ** Implementation of the non-aggregate min() and max() functions |
| 43 */ |
| 44 static void minmaxFunc( |
| 45 sqlite3_context *context, |
| 46 int argc, |
| 47 sqlite3_value **argv |
| 48 ){ |
| 49 int i; |
| 50 int mask; /* 0 for min() or 0xffffffff for max() */ |
| 51 int iBest; |
| 52 CollSeq *pColl; |
| 53 |
| 54 assert( argc>1 ); |
| 55 mask = sqlite3_user_data(context)==0 ? 0 : -1; |
| 56 pColl = sqlite3GetFuncCollSeq(context); |
| 57 assert( pColl ); |
| 58 assert( mask==-1 || mask==0 ); |
| 59 iBest = 0; |
| 60 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; |
| 61 for(i=1; i<argc; i++){ |
| 62 if( sqlite3_value_type(argv[i])==SQLITE_NULL ) return; |
| 63 if( (sqlite3MemCompare(argv[iBest], argv[i], pColl)^mask)>=0 ){ |
| 64 testcase( mask==0 ); |
| 65 iBest = i; |
| 66 } |
| 67 } |
| 68 sqlite3_result_value(context, argv[iBest]); |
| 69 } |
| 70 |
| 71 /* |
| 72 ** Return the type of the argument. |
| 73 */ |
| 74 static void typeofFunc( |
| 75 sqlite3_context *context, |
| 76 int NotUsed, |
| 77 sqlite3_value **argv |
| 78 ){ |
| 79 const char *z = 0; |
| 80 UNUSED_PARAMETER(NotUsed); |
| 81 switch( sqlite3_value_type(argv[0]) ){ |
| 82 case SQLITE_INTEGER: z = "integer"; break; |
| 83 case SQLITE_TEXT: z = "text"; break; |
| 84 case SQLITE_FLOAT: z = "real"; break; |
| 85 case SQLITE_BLOB: z = "blob"; break; |
| 86 default: z = "null"; break; |
| 87 } |
| 88 sqlite3_result_text(context, z, -1, SQLITE_STATIC); |
| 89 } |
| 90 |
| 91 |
| 92 /* |
| 93 ** Implementation of the length() function |
| 94 */ |
| 95 static void lengthFunc( |
| 96 sqlite3_context *context, |
| 97 int argc, |
| 98 sqlite3_value **argv |
| 99 ){ |
| 100 int len; |
| 101 |
| 102 assert( argc==1 ); |
| 103 UNUSED_PARAMETER(argc); |
| 104 switch( sqlite3_value_type(argv[0]) ){ |
| 105 case SQLITE_BLOB: |
| 106 case SQLITE_INTEGER: |
| 107 case SQLITE_FLOAT: { |
| 108 sqlite3_result_int(context, sqlite3_value_bytes(argv[0])); |
| 109 break; |
| 110 } |
| 111 case SQLITE_TEXT: { |
| 112 const unsigned char *z = sqlite3_value_text(argv[0]); |
| 113 if( z==0 ) return; |
| 114 len = 0; |
| 115 while( *z ){ |
| 116 len++; |
| 117 SQLITE_SKIP_UTF8(z); |
| 118 } |
| 119 sqlite3_result_int(context, len); |
| 120 break; |
| 121 } |
| 122 default: { |
| 123 sqlite3_result_null(context); |
| 124 break; |
| 125 } |
| 126 } |
| 127 } |
| 128 |
| 129 /* |
| 130 ** Implementation of the abs() function. |
| 131 ** |
| 132 ** IMP: R-23979-26855 The abs(X) function returns the absolute value of |
| 133 ** the numeric argument X. |
| 134 */ |
| 135 static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ |
| 136 assert( argc==1 ); |
| 137 UNUSED_PARAMETER(argc); |
| 138 switch( sqlite3_value_type(argv[0]) ){ |
| 139 case SQLITE_INTEGER: { |
| 140 i64 iVal = sqlite3_value_int64(argv[0]); |
| 141 if( iVal<0 ){ |
| 142 if( iVal==SMALLEST_INT64 ){ |
| 143 /* IMP: R-31676-45509 If X is the integer -9223372036854775808 |
| 144 ** then abs(X) throws an integer overflow error since there is no |
| 145 ** equivalent positive 64-bit two complement value. */ |
| 146 sqlite3_result_error(context, "integer overflow", -1); |
| 147 return; |
| 148 } |
| 149 iVal = -iVal; |
| 150 } |
| 151 sqlite3_result_int64(context, iVal); |
| 152 break; |
| 153 } |
| 154 case SQLITE_NULL: { |
| 155 /* IMP: R-37434-19929 Abs(X) returns NULL if X is NULL. */ |
| 156 sqlite3_result_null(context); |
| 157 break; |
| 158 } |
| 159 default: { |
| 160 /* Because sqlite3_value_double() returns 0.0 if the argument is not |
| 161 ** something that can be converted into a number, we have: |
| 162 ** IMP: R-01992-00519 Abs(X) returns 0.0 if X is a string or blob |
| 163 ** that cannot be converted to a numeric value. |
| 164 */ |
| 165 double rVal = sqlite3_value_double(argv[0]); |
| 166 if( rVal<0 ) rVal = -rVal; |
| 167 sqlite3_result_double(context, rVal); |
| 168 break; |
| 169 } |
| 170 } |
| 171 } |
| 172 |
| 173 /* |
| 174 ** Implementation of the instr() function. |
| 175 ** |
| 176 ** instr(haystack,needle) finds the first occurrence of needle |
| 177 ** in haystack and returns the number of previous characters plus 1, |
| 178 ** or 0 if needle does not occur within haystack. |
| 179 ** |
| 180 ** If both haystack and needle are BLOBs, then the result is one more than |
| 181 ** the number of bytes in haystack prior to the first occurrence of needle, |
| 182 ** or 0 if needle never occurs in haystack. |
| 183 */ |
| 184 static void instrFunc( |
| 185 sqlite3_context *context, |
| 186 int argc, |
| 187 sqlite3_value **argv |
| 188 ){ |
| 189 const unsigned char *zHaystack; |
| 190 const unsigned char *zNeedle; |
| 191 int nHaystack; |
| 192 int nNeedle; |
| 193 int typeHaystack, typeNeedle; |
| 194 int N = 1; |
| 195 int isText; |
| 196 |
| 197 UNUSED_PARAMETER(argc); |
| 198 typeHaystack = sqlite3_value_type(argv[0]); |
| 199 typeNeedle = sqlite3_value_type(argv[1]); |
| 200 if( typeHaystack==SQLITE_NULL || typeNeedle==SQLITE_NULL ) return; |
| 201 nHaystack = sqlite3_value_bytes(argv[0]); |
| 202 nNeedle = sqlite3_value_bytes(argv[1]); |
| 203 if( nNeedle>0 ){ |
| 204 if( typeHaystack==SQLITE_BLOB && typeNeedle==SQLITE_BLOB ){ |
| 205 zHaystack = sqlite3_value_blob(argv[0]); |
| 206 zNeedle = sqlite3_value_blob(argv[1]); |
| 207 assert( zNeedle!=0 ); |
| 208 assert( zHaystack!=0 || nHaystack==0 ); |
| 209 isText = 0; |
| 210 }else{ |
| 211 zHaystack = sqlite3_value_text(argv[0]); |
| 212 zNeedle = sqlite3_value_text(argv[1]); |
| 213 isText = 1; |
| 214 if( zHaystack==0 || zNeedle==0 ) return; |
| 215 } |
| 216 while( nNeedle<=nHaystack && memcmp(zHaystack, zNeedle, nNeedle)!=0 ){ |
| 217 N++; |
| 218 do{ |
| 219 nHaystack--; |
| 220 zHaystack++; |
| 221 }while( isText && (zHaystack[0]&0xc0)==0x80 ); |
| 222 } |
| 223 if( nNeedle>nHaystack ) N = 0; |
| 224 } |
| 225 sqlite3_result_int(context, N); |
| 226 } |
| 227 |
| 228 /* |
| 229 ** Implementation of the printf() function. |
| 230 */ |
| 231 static void printfFunc( |
| 232 sqlite3_context *context, |
| 233 int argc, |
| 234 sqlite3_value **argv |
| 235 ){ |
| 236 PrintfArguments x; |
| 237 StrAccum str; |
| 238 const char *zFormat; |
| 239 int n; |
| 240 sqlite3 *db = sqlite3_context_db_handle(context); |
| 241 |
| 242 if( argc>=1 && (zFormat = (const char*)sqlite3_value_text(argv[0]))!=0 ){ |
| 243 x.nArg = argc-1; |
| 244 x.nUsed = 0; |
| 245 x.apArg = argv+1; |
| 246 sqlite3StrAccumInit(&str, db, 0, 0, db->aLimit[SQLITE_LIMIT_LENGTH]); |
| 247 str.printfFlags = SQLITE_PRINTF_SQLFUNC; |
| 248 sqlite3XPrintf(&str, zFormat, &x); |
| 249 n = str.nChar; |
| 250 sqlite3_result_text(context, sqlite3StrAccumFinish(&str), n, |
| 251 SQLITE_DYNAMIC); |
| 252 } |
| 253 } |
| 254 |
| 255 /* |
| 256 ** Implementation of the substr() function. |
| 257 ** |
| 258 ** substr(x,p1,p2) returns p2 characters of x[] beginning with p1. |
| 259 ** p1 is 1-indexed. So substr(x,1,1) returns the first character |
| 260 ** of x. If x is text, then we actually count UTF-8 characters. |
| 261 ** If x is a blob, then we count bytes. |
| 262 ** |
| 263 ** If p1 is negative, then we begin abs(p1) from the end of x[]. |
| 264 ** |
| 265 ** If p2 is negative, return the p2 characters preceding p1. |
| 266 */ |
| 267 static void substrFunc( |
| 268 sqlite3_context *context, |
| 269 int argc, |
| 270 sqlite3_value **argv |
| 271 ){ |
| 272 const unsigned char *z; |
| 273 const unsigned char *z2; |
| 274 int len; |
| 275 int p0type; |
| 276 i64 p1, p2; |
| 277 int negP2 = 0; |
| 278 |
| 279 assert( argc==3 || argc==2 ); |
| 280 if( sqlite3_value_type(argv[1])==SQLITE_NULL |
| 281 || (argc==3 && sqlite3_value_type(argv[2])==SQLITE_NULL) |
| 282 ){ |
| 283 return; |
| 284 } |
| 285 p0type = sqlite3_value_type(argv[0]); |
| 286 p1 = sqlite3_value_int(argv[1]); |
| 287 if( p0type==SQLITE_BLOB ){ |
| 288 len = sqlite3_value_bytes(argv[0]); |
| 289 z = sqlite3_value_blob(argv[0]); |
| 290 if( z==0 ) return; |
| 291 assert( len==sqlite3_value_bytes(argv[0]) ); |
| 292 }else{ |
| 293 z = sqlite3_value_text(argv[0]); |
| 294 if( z==0 ) return; |
| 295 len = 0; |
| 296 if( p1<0 ){ |
| 297 for(z2=z; *z2; len++){ |
| 298 SQLITE_SKIP_UTF8(z2); |
| 299 } |
| 300 } |
| 301 } |
| 302 #ifdef SQLITE_SUBSTR_COMPATIBILITY |
| 303 /* If SUBSTR_COMPATIBILITY is defined then substr(X,0,N) work the same as |
| 304 ** as substr(X,1,N) - it returns the first N characters of X. This |
| 305 ** is essentially a back-out of the bug-fix in check-in [5fc125d362df4b8] |
| 306 ** from 2009-02-02 for compatibility of applications that exploited the |
| 307 ** old buggy behavior. */ |
| 308 if( p1==0 ) p1 = 1; /* <rdar://problem/6778339> */ |
| 309 #endif |
| 310 if( argc==3 ){ |
| 311 p2 = sqlite3_value_int(argv[2]); |
| 312 if( p2<0 ){ |
| 313 p2 = -p2; |
| 314 negP2 = 1; |
| 315 } |
| 316 }else{ |
| 317 p2 = sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH]; |
| 318 } |
| 319 if( p1<0 ){ |
| 320 p1 += len; |
| 321 if( p1<0 ){ |
| 322 p2 += p1; |
| 323 if( p2<0 ) p2 = 0; |
| 324 p1 = 0; |
| 325 } |
| 326 }else if( p1>0 ){ |
| 327 p1--; |
| 328 }else if( p2>0 ){ |
| 329 p2--; |
| 330 } |
| 331 if( negP2 ){ |
| 332 p1 -= p2; |
| 333 if( p1<0 ){ |
| 334 p2 += p1; |
| 335 p1 = 0; |
| 336 } |
| 337 } |
| 338 assert( p1>=0 && p2>=0 ); |
| 339 if( p0type!=SQLITE_BLOB ){ |
| 340 while( *z && p1 ){ |
| 341 SQLITE_SKIP_UTF8(z); |
| 342 p1--; |
| 343 } |
| 344 for(z2=z; *z2 && p2; p2--){ |
| 345 SQLITE_SKIP_UTF8(z2); |
| 346 } |
| 347 sqlite3_result_text64(context, (char*)z, z2-z, SQLITE_TRANSIENT, |
| 348 SQLITE_UTF8); |
| 349 }else{ |
| 350 if( p1+p2>len ){ |
| 351 p2 = len-p1; |
| 352 if( p2<0 ) p2 = 0; |
| 353 } |
| 354 sqlite3_result_blob64(context, (char*)&z[p1], (u64)p2, SQLITE_TRANSIENT); |
| 355 } |
| 356 } |
| 357 |
| 358 /* |
| 359 ** Implementation of the round() function |
| 360 */ |
| 361 #ifndef SQLITE_OMIT_FLOATING_POINT |
| 362 static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ |
| 363 int n = 0; |
| 364 double r; |
| 365 char *zBuf; |
| 366 assert( argc==1 || argc==2 ); |
| 367 if( argc==2 ){ |
| 368 if( SQLITE_NULL==sqlite3_value_type(argv[1]) ) return; |
| 369 n = sqlite3_value_int(argv[1]); |
| 370 if( n>30 ) n = 30; |
| 371 if( n<0 ) n = 0; |
| 372 } |
| 373 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; |
| 374 r = sqlite3_value_double(argv[0]); |
| 375 /* If Y==0 and X will fit in a 64-bit int, |
| 376 ** handle the rounding directly, |
| 377 ** otherwise use printf. |
| 378 */ |
| 379 if( n==0 && r>=0 && r<LARGEST_INT64-1 ){ |
| 380 r = (double)((sqlite_int64)(r+0.5)); |
| 381 }else if( n==0 && r<0 && (-r)<LARGEST_INT64-1 ){ |
| 382 r = -(double)((sqlite_int64)((-r)+0.5)); |
| 383 }else{ |
| 384 zBuf = sqlite3_mprintf("%.*f",n,r); |
| 385 if( zBuf==0 ){ |
| 386 sqlite3_result_error_nomem(context); |
| 387 return; |
| 388 } |
| 389 sqlite3AtoF(zBuf, &r, sqlite3Strlen30(zBuf), SQLITE_UTF8); |
| 390 sqlite3_free(zBuf); |
| 391 } |
| 392 sqlite3_result_double(context, r); |
| 393 } |
| 394 #endif |
| 395 |
| 396 /* |
| 397 ** Allocate nByte bytes of space using sqlite3Malloc(). If the |
| 398 ** allocation fails, call sqlite3_result_error_nomem() to notify |
| 399 ** the database handle that malloc() has failed and return NULL. |
| 400 ** If nByte is larger than the maximum string or blob length, then |
| 401 ** raise an SQLITE_TOOBIG exception and return NULL. |
| 402 */ |
| 403 static void *contextMalloc(sqlite3_context *context, i64 nByte){ |
| 404 char *z; |
| 405 sqlite3 *db = sqlite3_context_db_handle(context); |
| 406 assert( nByte>0 ); |
| 407 testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH] ); |
| 408 testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH]+1 ); |
| 409 if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){ |
| 410 sqlite3_result_error_toobig(context); |
| 411 z = 0; |
| 412 }else{ |
| 413 z = sqlite3Malloc(nByte); |
| 414 if( !z ){ |
| 415 sqlite3_result_error_nomem(context); |
| 416 } |
| 417 } |
| 418 return z; |
| 419 } |
| 420 |
| 421 /* |
| 422 ** Implementation of the upper() and lower() SQL functions. |
| 423 */ |
| 424 static void upperFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ |
| 425 char *z1; |
| 426 const char *z2; |
| 427 int i, n; |
| 428 UNUSED_PARAMETER(argc); |
| 429 z2 = (char*)sqlite3_value_text(argv[0]); |
| 430 n = sqlite3_value_bytes(argv[0]); |
| 431 /* Verify that the call to _bytes() does not invalidate the _text() pointer */ |
| 432 assert( z2==(char*)sqlite3_value_text(argv[0]) ); |
| 433 if( z2 ){ |
| 434 z1 = contextMalloc(context, ((i64)n)+1); |
| 435 if( z1 ){ |
| 436 for(i=0; i<n; i++){ |
| 437 z1[i] = (char)sqlite3Toupper(z2[i]); |
| 438 } |
| 439 sqlite3_result_text(context, z1, n, sqlite3_free); |
| 440 } |
| 441 } |
| 442 } |
| 443 static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ |
| 444 char *z1; |
| 445 const char *z2; |
| 446 int i, n; |
| 447 UNUSED_PARAMETER(argc); |
| 448 z2 = (char*)sqlite3_value_text(argv[0]); |
| 449 n = sqlite3_value_bytes(argv[0]); |
| 450 /* Verify that the call to _bytes() does not invalidate the _text() pointer */ |
| 451 assert( z2==(char*)sqlite3_value_text(argv[0]) ); |
| 452 if( z2 ){ |
| 453 z1 = contextMalloc(context, ((i64)n)+1); |
| 454 if( z1 ){ |
| 455 for(i=0; i<n; i++){ |
| 456 z1[i] = sqlite3Tolower(z2[i]); |
| 457 } |
| 458 sqlite3_result_text(context, z1, n, sqlite3_free); |
| 459 } |
| 460 } |
| 461 } |
| 462 |
| 463 /* |
| 464 ** Some functions like COALESCE() and IFNULL() and UNLIKELY() are implemented |
| 465 ** as VDBE code so that unused argument values do not have to be computed. |
| 466 ** However, we still need some kind of function implementation for this |
| 467 ** routines in the function table. The noopFunc macro provides this. |
| 468 ** noopFunc will never be called so it doesn't matter what the implementation |
| 469 ** is. We might as well use the "version()" function as a substitute. |
| 470 */ |
| 471 #define noopFunc versionFunc /* Substitute function - never called */ |
| 472 |
| 473 /* |
| 474 ** Implementation of random(). Return a random integer. |
| 475 */ |
| 476 static void randomFunc( |
| 477 sqlite3_context *context, |
| 478 int NotUsed, |
| 479 sqlite3_value **NotUsed2 |
| 480 ){ |
| 481 sqlite_int64 r; |
| 482 UNUSED_PARAMETER2(NotUsed, NotUsed2); |
| 483 sqlite3_randomness(sizeof(r), &r); |
| 484 if( r<0 ){ |
| 485 /* We need to prevent a random number of 0x8000000000000000 |
| 486 ** (or -9223372036854775808) since when you do abs() of that |
| 487 ** number of you get the same value back again. To do this |
| 488 ** in a way that is testable, mask the sign bit off of negative |
| 489 ** values, resulting in a positive value. Then take the |
| 490 ** 2s complement of that positive value. The end result can |
| 491 ** therefore be no less than -9223372036854775807. |
| 492 */ |
| 493 r = -(r & LARGEST_INT64); |
| 494 } |
| 495 sqlite3_result_int64(context, r); |
| 496 } |
| 497 |
| 498 /* |
| 499 ** Implementation of randomblob(N). Return a random blob |
| 500 ** that is N bytes long. |
| 501 */ |
| 502 static void randomBlob( |
| 503 sqlite3_context *context, |
| 504 int argc, |
| 505 sqlite3_value **argv |
| 506 ){ |
| 507 int n; |
| 508 unsigned char *p; |
| 509 assert( argc==1 ); |
| 510 UNUSED_PARAMETER(argc); |
| 511 n = sqlite3_value_int(argv[0]); |
| 512 if( n<1 ){ |
| 513 n = 1; |
| 514 } |
| 515 p = contextMalloc(context, n); |
| 516 if( p ){ |
| 517 sqlite3_randomness(n, p); |
| 518 sqlite3_result_blob(context, (char*)p, n, sqlite3_free); |
| 519 } |
| 520 } |
| 521 |
| 522 /* |
| 523 ** Implementation of the last_insert_rowid() SQL function. The return |
| 524 ** value is the same as the sqlite3_last_insert_rowid() API function. |
| 525 */ |
| 526 static void last_insert_rowid( |
| 527 sqlite3_context *context, |
| 528 int NotUsed, |
| 529 sqlite3_value **NotUsed2 |
| 530 ){ |
| 531 sqlite3 *db = sqlite3_context_db_handle(context); |
| 532 UNUSED_PARAMETER2(NotUsed, NotUsed2); |
| 533 /* IMP: R-51513-12026 The last_insert_rowid() SQL function is a |
| 534 ** wrapper around the sqlite3_last_insert_rowid() C/C++ interface |
| 535 ** function. */ |
| 536 sqlite3_result_int64(context, sqlite3_last_insert_rowid(db)); |
| 537 } |
| 538 |
| 539 /* |
| 540 ** Implementation of the changes() SQL function. |
| 541 ** |
| 542 ** IMP: R-62073-11209 The changes() SQL function is a wrapper |
| 543 ** around the sqlite3_changes() C/C++ function and hence follows the same |
| 544 ** rules for counting changes. |
| 545 */ |
| 546 static void changes( |
| 547 sqlite3_context *context, |
| 548 int NotUsed, |
| 549 sqlite3_value **NotUsed2 |
| 550 ){ |
| 551 sqlite3 *db = sqlite3_context_db_handle(context); |
| 552 UNUSED_PARAMETER2(NotUsed, NotUsed2); |
| 553 sqlite3_result_int(context, sqlite3_changes(db)); |
| 554 } |
| 555 |
| 556 /* |
| 557 ** Implementation of the total_changes() SQL function. The return value is |
| 558 ** the same as the sqlite3_total_changes() API function. |
| 559 */ |
| 560 static void total_changes( |
| 561 sqlite3_context *context, |
| 562 int NotUsed, |
| 563 sqlite3_value **NotUsed2 |
| 564 ){ |
| 565 sqlite3 *db = sqlite3_context_db_handle(context); |
| 566 UNUSED_PARAMETER2(NotUsed, NotUsed2); |
| 567 /* IMP: R-52756-41993 This function is a wrapper around the |
| 568 ** sqlite3_total_changes() C/C++ interface. */ |
| 569 sqlite3_result_int(context, sqlite3_total_changes(db)); |
| 570 } |
| 571 |
| 572 /* |
| 573 ** A structure defining how to do GLOB-style comparisons. |
| 574 */ |
| 575 struct compareInfo { |
| 576 u8 matchAll; /* "*" or "%" */ |
| 577 u8 matchOne; /* "?" or "_" */ |
| 578 u8 matchSet; /* "[" or 0 */ |
| 579 u8 noCase; /* true to ignore case differences */ |
| 580 }; |
| 581 |
| 582 /* |
| 583 ** For LIKE and GLOB matching on EBCDIC machines, assume that every |
| 584 ** character is exactly one byte in size. Also, provde the Utf8Read() |
| 585 ** macro for fast reading of the next character in the common case where |
| 586 ** the next character is ASCII. |
| 587 */ |
| 588 #if defined(SQLITE_EBCDIC) |
| 589 # define sqlite3Utf8Read(A) (*((*A)++)) |
| 590 # define Utf8Read(A) (*(A++)) |
| 591 #else |
| 592 # define Utf8Read(A) (A[0]<0x80?*(A++):sqlite3Utf8Read(&A)) |
| 593 #endif |
| 594 |
| 595 static const struct compareInfo globInfo = { '*', '?', '[', 0 }; |
| 596 /* The correct SQL-92 behavior is for the LIKE operator to ignore |
| 597 ** case. Thus 'a' LIKE 'A' would be true. */ |
| 598 static const struct compareInfo likeInfoNorm = { '%', '_', 0, 1 }; |
| 599 /* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator |
| 600 ** is case sensitive causing 'a' LIKE 'A' to be false */ |
| 601 static const struct compareInfo likeInfoAlt = { '%', '_', 0, 0 }; |
| 602 |
| 603 /* |
| 604 ** Possible error returns from patternMatch() |
| 605 */ |
| 606 #define SQLITE_MATCH 0 |
| 607 #define SQLITE_NOMATCH 1 |
| 608 #define SQLITE_NOWILDCARDMATCH 2 |
| 609 |
| 610 /* |
| 611 ** Compare two UTF-8 strings for equality where the first string is |
| 612 ** a GLOB or LIKE expression. Return values: |
| 613 ** |
| 614 ** SQLITE_MATCH: Match |
| 615 ** SQLITE_NOMATCH: No match |
| 616 ** SQLITE_NOWILDCARDMATCH: No match in spite of having * or % wildcards. |
| 617 ** |
| 618 ** Globbing rules: |
| 619 ** |
| 620 ** '*' Matches any sequence of zero or more characters. |
| 621 ** |
| 622 ** '?' Matches exactly one character. |
| 623 ** |
| 624 ** [...] Matches one character from the enclosed list of |
| 625 ** characters. |
| 626 ** |
| 627 ** [^...] Matches one character not in the enclosed list. |
| 628 ** |
| 629 ** With the [...] and [^...] matching, a ']' character can be included |
| 630 ** in the list by making it the first character after '[' or '^'. A |
| 631 ** range of characters can be specified using '-'. Example: |
| 632 ** "[a-z]" matches any single lower-case letter. To match a '-', make |
| 633 ** it the last character in the list. |
| 634 ** |
| 635 ** Like matching rules: |
| 636 ** |
| 637 ** '%' Matches any sequence of zero or more characters |
| 638 ** |
| 639 *** '_' Matches any one character |
| 640 ** |
| 641 ** Ec Where E is the "esc" character and c is any other |
| 642 ** character, including '%', '_', and esc, match exactly c. |
| 643 ** |
| 644 ** The comments within this routine usually assume glob matching. |
| 645 ** |
| 646 ** This routine is usually quick, but can be N**2 in the worst case. |
| 647 */ |
| 648 static int patternCompare( |
| 649 const u8 *zPattern, /* The glob pattern */ |
| 650 const u8 *zString, /* The string to compare against the glob */ |
| 651 const struct compareInfo *pInfo, /* Information about how to do the compare */ |
| 652 u32 matchOther /* The escape char (LIKE) or '[' (GLOB) */ |
| 653 ){ |
| 654 u32 c, c2; /* Next pattern and input string chars */ |
| 655 u32 matchOne = pInfo->matchOne; /* "?" or "_" */ |
| 656 u32 matchAll = pInfo->matchAll; /* "*" or "%" */ |
| 657 u8 noCase = pInfo->noCase; /* True if uppercase==lowercase */ |
| 658 const u8 *zEscaped = 0; /* One past the last escaped input char */ |
| 659 |
| 660 while( (c = Utf8Read(zPattern))!=0 ){ |
| 661 if( c==matchAll ){ /* Match "*" */ |
| 662 /* Skip over multiple "*" characters in the pattern. If there |
| 663 ** are also "?" characters, skip those as well, but consume a |
| 664 ** single character of the input string for each "?" skipped */ |
| 665 while( (c=Utf8Read(zPattern)) == matchAll || c == matchOne ){ |
| 666 if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){ |
| 667 return SQLITE_NOWILDCARDMATCH; |
| 668 } |
| 669 } |
| 670 if( c==0 ){ |
| 671 return SQLITE_MATCH; /* "*" at the end of the pattern matches */ |
| 672 }else if( c==matchOther ){ |
| 673 if( pInfo->matchSet==0 ){ |
| 674 c = sqlite3Utf8Read(&zPattern); |
| 675 if( c==0 ) return SQLITE_NOWILDCARDMATCH; |
| 676 }else{ |
| 677 /* "[...]" immediately follows the "*". We have to do a slow |
| 678 ** recursive search in this case, but it is an unusual case. */ |
| 679 assert( matchOther<0x80 ); /* '[' is a single-byte character */ |
| 680 while( *zString ){ |
| 681 int bMatch = patternCompare(&zPattern[-1],zString,pInfo,matchOther); |
| 682 if( bMatch!=SQLITE_NOMATCH ) return bMatch; |
| 683 SQLITE_SKIP_UTF8(zString); |
| 684 } |
| 685 return SQLITE_NOWILDCARDMATCH; |
| 686 } |
| 687 } |
| 688 |
| 689 /* At this point variable c contains the first character of the |
| 690 ** pattern string past the "*". Search in the input string for the |
| 691 ** first matching character and recursively continue the match from |
| 692 ** that point. |
| 693 ** |
| 694 ** For a case-insensitive search, set variable cx to be the same as |
| 695 ** c but in the other case and search the input string for either |
| 696 ** c or cx. |
| 697 */ |
| 698 if( c<=0x80 ){ |
| 699 u32 cx; |
| 700 int bMatch; |
| 701 if( noCase ){ |
| 702 cx = sqlite3Toupper(c); |
| 703 c = sqlite3Tolower(c); |
| 704 }else{ |
| 705 cx = c; |
| 706 } |
| 707 while( (c2 = *(zString++))!=0 ){ |
| 708 if( c2!=c && c2!=cx ) continue; |
| 709 bMatch = patternCompare(zPattern,zString,pInfo,matchOther); |
| 710 if( bMatch!=SQLITE_NOMATCH ) return bMatch; |
| 711 } |
| 712 }else{ |
| 713 int bMatch; |
| 714 while( (c2 = Utf8Read(zString))!=0 ){ |
| 715 if( c2!=c ) continue; |
| 716 bMatch = patternCompare(zPattern,zString,pInfo,matchOther); |
| 717 if( bMatch!=SQLITE_NOMATCH ) return bMatch; |
| 718 } |
| 719 } |
| 720 return SQLITE_NOWILDCARDMATCH; |
| 721 } |
| 722 if( c==matchOther ){ |
| 723 if( pInfo->matchSet==0 ){ |
| 724 c = sqlite3Utf8Read(&zPattern); |
| 725 if( c==0 ) return SQLITE_NOMATCH; |
| 726 zEscaped = zPattern; |
| 727 }else{ |
| 728 u32 prior_c = 0; |
| 729 int seen = 0; |
| 730 int invert = 0; |
| 731 c = sqlite3Utf8Read(&zString); |
| 732 if( c==0 ) return SQLITE_NOMATCH; |
| 733 c2 = sqlite3Utf8Read(&zPattern); |
| 734 if( c2=='^' ){ |
| 735 invert = 1; |
| 736 c2 = sqlite3Utf8Read(&zPattern); |
| 737 } |
| 738 if( c2==']' ){ |
| 739 if( c==']' ) seen = 1; |
| 740 c2 = sqlite3Utf8Read(&zPattern); |
| 741 } |
| 742 while( c2 && c2!=']' ){ |
| 743 if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){ |
| 744 c2 = sqlite3Utf8Read(&zPattern); |
| 745 if( c>=prior_c && c<=c2 ) seen = 1; |
| 746 prior_c = 0; |
| 747 }else{ |
| 748 if( c==c2 ){ |
| 749 seen = 1; |
| 750 } |
| 751 prior_c = c2; |
| 752 } |
| 753 c2 = sqlite3Utf8Read(&zPattern); |
| 754 } |
| 755 if( c2==0 || (seen ^ invert)==0 ){ |
| 756 return SQLITE_NOMATCH; |
| 757 } |
| 758 continue; |
| 759 } |
| 760 } |
| 761 c2 = Utf8Read(zString); |
| 762 if( c==c2 ) continue; |
| 763 if( noCase && sqlite3Tolower(c)==sqlite3Tolower(c2) && c<0x80 && c2<0x80 ){ |
| 764 continue; |
| 765 } |
| 766 if( c==matchOne && zPattern!=zEscaped && c2!=0 ) continue; |
| 767 return SQLITE_NOMATCH; |
| 768 } |
| 769 return *zString==0 ? SQLITE_MATCH : SQLITE_NOMATCH; |
| 770 } |
| 771 |
| 772 /* |
| 773 ** The sqlite3_strglob() interface. Return 0 on a match (like strcmp()) and |
| 774 ** non-zero if there is no match. |
| 775 */ |
| 776 int sqlite3_strglob(const char *zGlobPattern, const char *zString){ |
| 777 return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, '['); |
| 778 } |
| 779 |
| 780 /* |
| 781 ** The sqlite3_strlike() interface. Return 0 on a match and non-zero for |
| 782 ** a miss - like strcmp(). |
| 783 */ |
| 784 int sqlite3_strlike(const char *zPattern, const char *zStr, unsigned int esc){ |
| 785 return patternCompare((u8*)zPattern, (u8*)zStr, &likeInfoNorm, esc); |
| 786 } |
| 787 |
| 788 /* |
| 789 ** Count the number of times that the LIKE operator (or GLOB which is |
| 790 ** just a variation of LIKE) gets called. This is used for testing |
| 791 ** only. |
| 792 */ |
| 793 #ifdef SQLITE_TEST |
| 794 int sqlite3_like_count = 0; |
| 795 #endif |
| 796 |
| 797 |
| 798 /* |
| 799 ** Implementation of the like() SQL function. This function implements |
| 800 ** the build-in LIKE operator. The first argument to the function is the |
| 801 ** pattern and the second argument is the string. So, the SQL statements: |
| 802 ** |
| 803 ** A LIKE B |
| 804 ** |
| 805 ** is implemented as like(B,A). |
| 806 ** |
| 807 ** This same function (with a different compareInfo structure) computes |
| 808 ** the GLOB operator. |
| 809 */ |
| 810 static void likeFunc( |
| 811 sqlite3_context *context, |
| 812 int argc, |
| 813 sqlite3_value **argv |
| 814 ){ |
| 815 const unsigned char *zA, *zB; |
| 816 u32 escape; |
| 817 int nPat; |
| 818 sqlite3 *db = sqlite3_context_db_handle(context); |
| 819 struct compareInfo *pInfo = sqlite3_user_data(context); |
| 820 |
| 821 #ifdef SQLITE_LIKE_DOESNT_MATCH_BLOBS |
| 822 if( sqlite3_value_type(argv[0])==SQLITE_BLOB |
| 823 || sqlite3_value_type(argv[1])==SQLITE_BLOB |
| 824 ){ |
| 825 #ifdef SQLITE_TEST |
| 826 sqlite3_like_count++; |
| 827 #endif |
| 828 sqlite3_result_int(context, 0); |
| 829 return; |
| 830 } |
| 831 #endif |
| 832 zB = sqlite3_value_text(argv[0]); |
| 833 zA = sqlite3_value_text(argv[1]); |
| 834 |
| 835 /* Limit the length of the LIKE or GLOB pattern to avoid problems |
| 836 ** of deep recursion and N*N behavior in patternCompare(). |
| 837 */ |
| 838 nPat = sqlite3_value_bytes(argv[0]); |
| 839 testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ); |
| 840 testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]+1 ); |
| 841 if( nPat > db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ){ |
| 842 sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1); |
| 843 return; |
| 844 } |
| 845 assert( zB==sqlite3_value_text(argv[0]) ); /* Encoding did not change */ |
| 846 |
| 847 if( argc==3 ){ |
| 848 /* The escape character string must consist of a single UTF-8 character. |
| 849 ** Otherwise, return an error. |
| 850 */ |
| 851 const unsigned char *zEsc = sqlite3_value_text(argv[2]); |
| 852 if( zEsc==0 ) return; |
| 853 if( sqlite3Utf8CharLen((char*)zEsc, -1)!=1 ){ |
| 854 sqlite3_result_error(context, |
| 855 "ESCAPE expression must be a single character", -1); |
| 856 return; |
| 857 } |
| 858 escape = sqlite3Utf8Read(&zEsc); |
| 859 }else{ |
| 860 escape = pInfo->matchSet; |
| 861 } |
| 862 if( zA && zB ){ |
| 863 #ifdef SQLITE_TEST |
| 864 sqlite3_like_count++; |
| 865 #endif |
| 866 sqlite3_result_int(context, patternCompare(zB, zA, pInfo, escape)==SQLITE_MA
TCH); |
| 867 } |
| 868 } |
| 869 |
| 870 /* |
| 871 ** Implementation of the NULLIF(x,y) function. The result is the first |
| 872 ** argument if the arguments are different. The result is NULL if the |
| 873 ** arguments are equal to each other. |
| 874 */ |
| 875 static void nullifFunc( |
| 876 sqlite3_context *context, |
| 877 int NotUsed, |
| 878 sqlite3_value **argv |
| 879 ){ |
| 880 CollSeq *pColl = sqlite3GetFuncCollSeq(context); |
| 881 UNUSED_PARAMETER(NotUsed); |
| 882 if( sqlite3MemCompare(argv[0], argv[1], pColl)!=0 ){ |
| 883 sqlite3_result_value(context, argv[0]); |
| 884 } |
| 885 } |
| 886 |
| 887 /* |
| 888 ** Implementation of the sqlite_version() function. The result is the version |
| 889 ** of the SQLite library that is running. |
| 890 */ |
| 891 static void versionFunc( |
| 892 sqlite3_context *context, |
| 893 int NotUsed, |
| 894 sqlite3_value **NotUsed2 |
| 895 ){ |
| 896 UNUSED_PARAMETER2(NotUsed, NotUsed2); |
| 897 /* IMP: R-48699-48617 This function is an SQL wrapper around the |
| 898 ** sqlite3_libversion() C-interface. */ |
| 899 sqlite3_result_text(context, sqlite3_libversion(), -1, SQLITE_STATIC); |
| 900 } |
| 901 |
| 902 /* |
| 903 ** Implementation of the sqlite_source_id() function. The result is a string |
| 904 ** that identifies the particular version of the source code used to build |
| 905 ** SQLite. |
| 906 */ |
| 907 static void sourceidFunc( |
| 908 sqlite3_context *context, |
| 909 int NotUsed, |
| 910 sqlite3_value **NotUsed2 |
| 911 ){ |
| 912 UNUSED_PARAMETER2(NotUsed, NotUsed2); |
| 913 /* IMP: R-24470-31136 This function is an SQL wrapper around the |
| 914 ** sqlite3_sourceid() C interface. */ |
| 915 sqlite3_result_text(context, sqlite3_sourceid(), -1, SQLITE_STATIC); |
| 916 } |
| 917 |
| 918 /* |
| 919 ** Implementation of the sqlite_log() function. This is a wrapper around |
| 920 ** sqlite3_log(). The return value is NULL. The function exists purely for |
| 921 ** its side-effects. |
| 922 */ |
| 923 static void errlogFunc( |
| 924 sqlite3_context *context, |
| 925 int argc, |
| 926 sqlite3_value **argv |
| 927 ){ |
| 928 UNUSED_PARAMETER(argc); |
| 929 UNUSED_PARAMETER(context); |
| 930 sqlite3_log(sqlite3_value_int(argv[0]), "%s", sqlite3_value_text(argv[1])); |
| 931 } |
| 932 |
| 933 /* |
| 934 ** Implementation of the sqlite_compileoption_used() function. |
| 935 ** The result is an integer that identifies if the compiler option |
| 936 ** was used to build SQLite. |
| 937 */ |
| 938 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS |
| 939 static void compileoptionusedFunc( |
| 940 sqlite3_context *context, |
| 941 int argc, |
| 942 sqlite3_value **argv |
| 943 ){ |
| 944 const char *zOptName; |
| 945 assert( argc==1 ); |
| 946 UNUSED_PARAMETER(argc); |
| 947 /* IMP: R-39564-36305 The sqlite_compileoption_used() SQL |
| 948 ** function is a wrapper around the sqlite3_compileoption_used() C/C++ |
| 949 ** function. |
| 950 */ |
| 951 if( (zOptName = (const char*)sqlite3_value_text(argv[0]))!=0 ){ |
| 952 sqlite3_result_int(context, sqlite3_compileoption_used(zOptName)); |
| 953 } |
| 954 } |
| 955 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ |
| 956 |
| 957 /* |
| 958 ** Implementation of the sqlite_compileoption_get() function. |
| 959 ** The result is a string that identifies the compiler options |
| 960 ** used to build SQLite. |
| 961 */ |
| 962 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS |
| 963 static void compileoptiongetFunc( |
| 964 sqlite3_context *context, |
| 965 int argc, |
| 966 sqlite3_value **argv |
| 967 ){ |
| 968 int n; |
| 969 assert( argc==1 ); |
| 970 UNUSED_PARAMETER(argc); |
| 971 /* IMP: R-04922-24076 The sqlite_compileoption_get() SQL function |
| 972 ** is a wrapper around the sqlite3_compileoption_get() C/C++ function. |
| 973 */ |
| 974 n = sqlite3_value_int(argv[0]); |
| 975 sqlite3_result_text(context, sqlite3_compileoption_get(n), -1, SQLITE_STATIC); |
| 976 } |
| 977 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ |
| 978 |
| 979 /* Array for converting from half-bytes (nybbles) into ASCII hex |
| 980 ** digits. */ |
| 981 static const char hexdigits[] = { |
| 982 '0', '1', '2', '3', '4', '5', '6', '7', |
| 983 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' |
| 984 }; |
| 985 |
| 986 /* |
| 987 ** Implementation of the QUOTE() function. This function takes a single |
| 988 ** argument. If the argument is numeric, the return value is the same as |
| 989 ** the argument. If the argument is NULL, the return value is the string |
| 990 ** "NULL". Otherwise, the argument is enclosed in single quotes with |
| 991 ** single-quote escapes. |
| 992 */ |
| 993 static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ |
| 994 assert( argc==1 ); |
| 995 UNUSED_PARAMETER(argc); |
| 996 switch( sqlite3_value_type(argv[0]) ){ |
| 997 case SQLITE_FLOAT: { |
| 998 double r1, r2; |
| 999 char zBuf[50]; |
| 1000 r1 = sqlite3_value_double(argv[0]); |
| 1001 sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.15g", r1); |
| 1002 sqlite3AtoF(zBuf, &r2, 20, SQLITE_UTF8); |
| 1003 if( r1!=r2 ){ |
| 1004 sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.20e", r1); |
| 1005 } |
| 1006 sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT); |
| 1007 break; |
| 1008 } |
| 1009 case SQLITE_INTEGER: { |
| 1010 sqlite3_result_value(context, argv[0]); |
| 1011 break; |
| 1012 } |
| 1013 case SQLITE_BLOB: { |
| 1014 char *zText = 0; |
| 1015 char const *zBlob = sqlite3_value_blob(argv[0]); |
| 1016 int nBlob = sqlite3_value_bytes(argv[0]); |
| 1017 assert( zBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */ |
| 1018 zText = (char *)contextMalloc(context, (2*(i64)nBlob)+4); |
| 1019 if( zText ){ |
| 1020 int i; |
| 1021 for(i=0; i<nBlob; i++){ |
| 1022 zText[(i*2)+2] = hexdigits[(zBlob[i]>>4)&0x0F]; |
| 1023 zText[(i*2)+3] = hexdigits[(zBlob[i])&0x0F]; |
| 1024 } |
| 1025 zText[(nBlob*2)+2] = '\''; |
| 1026 zText[(nBlob*2)+3] = '\0'; |
| 1027 zText[0] = 'X'; |
| 1028 zText[1] = '\''; |
| 1029 sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT); |
| 1030 sqlite3_free(zText); |
| 1031 } |
| 1032 break; |
| 1033 } |
| 1034 case SQLITE_TEXT: { |
| 1035 int i,j; |
| 1036 u64 n; |
| 1037 const unsigned char *zArg = sqlite3_value_text(argv[0]); |
| 1038 char *z; |
| 1039 |
| 1040 if( zArg==0 ) return; |
| 1041 for(i=0, n=0; zArg[i]; i++){ if( zArg[i]=='\'' ) n++; } |
| 1042 z = contextMalloc(context, ((i64)i)+((i64)n)+3); |
| 1043 if( z ){ |
| 1044 z[0] = '\''; |
| 1045 for(i=0, j=1; zArg[i]; i++){ |
| 1046 z[j++] = zArg[i]; |
| 1047 if( zArg[i]=='\'' ){ |
| 1048 z[j++] = '\''; |
| 1049 } |
| 1050 } |
| 1051 z[j++] = '\''; |
| 1052 z[j] = 0; |
| 1053 sqlite3_result_text(context, z, j, sqlite3_free); |
| 1054 } |
| 1055 break; |
| 1056 } |
| 1057 default: { |
| 1058 assert( sqlite3_value_type(argv[0])==SQLITE_NULL ); |
| 1059 sqlite3_result_text(context, "NULL", 4, SQLITE_STATIC); |
| 1060 break; |
| 1061 } |
| 1062 } |
| 1063 } |
| 1064 |
| 1065 /* |
| 1066 ** The unicode() function. Return the integer unicode code-point value |
| 1067 ** for the first character of the input string. |
| 1068 */ |
| 1069 static void unicodeFunc( |
| 1070 sqlite3_context *context, |
| 1071 int argc, |
| 1072 sqlite3_value **argv |
| 1073 ){ |
| 1074 const unsigned char *z = sqlite3_value_text(argv[0]); |
| 1075 (void)argc; |
| 1076 if( z && z[0] ) sqlite3_result_int(context, sqlite3Utf8Read(&z)); |
| 1077 } |
| 1078 |
| 1079 /* |
| 1080 ** The char() function takes zero or more arguments, each of which is |
| 1081 ** an integer. It constructs a string where each character of the string |
| 1082 ** is the unicode character for the corresponding integer argument. |
| 1083 */ |
| 1084 static void charFunc( |
| 1085 sqlite3_context *context, |
| 1086 int argc, |
| 1087 sqlite3_value **argv |
| 1088 ){ |
| 1089 unsigned char *z, *zOut; |
| 1090 int i; |
| 1091 zOut = z = sqlite3_malloc64( argc*4+1 ); |
| 1092 if( z==0 ){ |
| 1093 sqlite3_result_error_nomem(context); |
| 1094 return; |
| 1095 } |
| 1096 for(i=0; i<argc; i++){ |
| 1097 sqlite3_int64 x; |
| 1098 unsigned c; |
| 1099 x = sqlite3_value_int64(argv[i]); |
| 1100 if( x<0 || x>0x10ffff ) x = 0xfffd; |
| 1101 c = (unsigned)(x & 0x1fffff); |
| 1102 if( c<0x00080 ){ |
| 1103 *zOut++ = (u8)(c&0xFF); |
| 1104 }else if( c<0x00800 ){ |
| 1105 *zOut++ = 0xC0 + (u8)((c>>6)&0x1F); |
| 1106 *zOut++ = 0x80 + (u8)(c & 0x3F); |
| 1107 }else if( c<0x10000 ){ |
| 1108 *zOut++ = 0xE0 + (u8)((c>>12)&0x0F); |
| 1109 *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); |
| 1110 *zOut++ = 0x80 + (u8)(c & 0x3F); |
| 1111 }else{ |
| 1112 *zOut++ = 0xF0 + (u8)((c>>18) & 0x07); |
| 1113 *zOut++ = 0x80 + (u8)((c>>12) & 0x3F); |
| 1114 *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); |
| 1115 *zOut++ = 0x80 + (u8)(c & 0x3F); |
| 1116 } \ |
| 1117 } |
| 1118 sqlite3_result_text64(context, (char*)z, zOut-z, sqlite3_free, SQLITE_UTF8); |
| 1119 } |
| 1120 |
| 1121 /* |
| 1122 ** The hex() function. Interpret the argument as a blob. Return |
| 1123 ** a hexadecimal rendering as text. |
| 1124 */ |
| 1125 static void hexFunc( |
| 1126 sqlite3_context *context, |
| 1127 int argc, |
| 1128 sqlite3_value **argv |
| 1129 ){ |
| 1130 int i, n; |
| 1131 const unsigned char *pBlob; |
| 1132 char *zHex, *z; |
| 1133 assert( argc==1 ); |
| 1134 UNUSED_PARAMETER(argc); |
| 1135 pBlob = sqlite3_value_blob(argv[0]); |
| 1136 n = sqlite3_value_bytes(argv[0]); |
| 1137 assert( pBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */ |
| 1138 z = zHex = contextMalloc(context, ((i64)n)*2 + 1); |
| 1139 if( zHex ){ |
| 1140 for(i=0; i<n; i++, pBlob++){ |
| 1141 unsigned char c = *pBlob; |
| 1142 *(z++) = hexdigits[(c>>4)&0xf]; |
| 1143 *(z++) = hexdigits[c&0xf]; |
| 1144 } |
| 1145 *z = 0; |
| 1146 sqlite3_result_text(context, zHex, n*2, sqlite3_free); |
| 1147 } |
| 1148 } |
| 1149 |
| 1150 /* |
| 1151 ** The zeroblob(N) function returns a zero-filled blob of size N bytes. |
| 1152 */ |
| 1153 static void zeroblobFunc( |
| 1154 sqlite3_context *context, |
| 1155 int argc, |
| 1156 sqlite3_value **argv |
| 1157 ){ |
| 1158 i64 n; |
| 1159 int rc; |
| 1160 assert( argc==1 ); |
| 1161 UNUSED_PARAMETER(argc); |
| 1162 n = sqlite3_value_int64(argv[0]); |
| 1163 if( n<0 ) n = 0; |
| 1164 rc = sqlite3_result_zeroblob64(context, n); /* IMP: R-00293-64994 */ |
| 1165 if( rc ){ |
| 1166 sqlite3_result_error_code(context, rc); |
| 1167 } |
| 1168 } |
| 1169 |
| 1170 /* |
| 1171 ** The replace() function. Three arguments are all strings: call |
| 1172 ** them A, B, and C. The result is also a string which is derived |
| 1173 ** from A by replacing every occurrence of B with C. The match |
| 1174 ** must be exact. Collating sequences are not used. |
| 1175 */ |
| 1176 static void replaceFunc( |
| 1177 sqlite3_context *context, |
| 1178 int argc, |
| 1179 sqlite3_value **argv |
| 1180 ){ |
| 1181 const unsigned char *zStr; /* The input string A */ |
| 1182 const unsigned char *zPattern; /* The pattern string B */ |
| 1183 const unsigned char *zRep; /* The replacement string C */ |
| 1184 unsigned char *zOut; /* The output */ |
| 1185 int nStr; /* Size of zStr */ |
| 1186 int nPattern; /* Size of zPattern */ |
| 1187 int nRep; /* Size of zRep */ |
| 1188 i64 nOut; /* Maximum size of zOut */ |
| 1189 int loopLimit; /* Last zStr[] that might match zPattern[] */ |
| 1190 int i, j; /* Loop counters */ |
| 1191 |
| 1192 assert( argc==3 ); |
| 1193 UNUSED_PARAMETER(argc); |
| 1194 zStr = sqlite3_value_text(argv[0]); |
| 1195 if( zStr==0 ) return; |
| 1196 nStr = sqlite3_value_bytes(argv[0]); |
| 1197 assert( zStr==sqlite3_value_text(argv[0]) ); /* No encoding change */ |
| 1198 zPattern = sqlite3_value_text(argv[1]); |
| 1199 if( zPattern==0 ){ |
| 1200 assert( sqlite3_value_type(argv[1])==SQLITE_NULL |
| 1201 || sqlite3_context_db_handle(context)->mallocFailed ); |
| 1202 return; |
| 1203 } |
| 1204 if( zPattern[0]==0 ){ |
| 1205 assert( sqlite3_value_type(argv[1])!=SQLITE_NULL ); |
| 1206 sqlite3_result_value(context, argv[0]); |
| 1207 return; |
| 1208 } |
| 1209 nPattern = sqlite3_value_bytes(argv[1]); |
| 1210 assert( zPattern==sqlite3_value_text(argv[1]) ); /* No encoding change */ |
| 1211 zRep = sqlite3_value_text(argv[2]); |
| 1212 if( zRep==0 ) return; |
| 1213 nRep = sqlite3_value_bytes(argv[2]); |
| 1214 assert( zRep==sqlite3_value_text(argv[2]) ); |
| 1215 nOut = nStr + 1; |
| 1216 assert( nOut<SQLITE_MAX_LENGTH ); |
| 1217 zOut = contextMalloc(context, (i64)nOut); |
| 1218 if( zOut==0 ){ |
| 1219 return; |
| 1220 } |
| 1221 loopLimit = nStr - nPattern; |
| 1222 for(i=j=0; i<=loopLimit; i++){ |
| 1223 if( zStr[i]!=zPattern[0] || memcmp(&zStr[i], zPattern, nPattern) ){ |
| 1224 zOut[j++] = zStr[i]; |
| 1225 }else{ |
| 1226 u8 *zOld; |
| 1227 sqlite3 *db = sqlite3_context_db_handle(context); |
| 1228 nOut += nRep - nPattern; |
| 1229 testcase( nOut-1==db->aLimit[SQLITE_LIMIT_LENGTH] ); |
| 1230 testcase( nOut-2==db->aLimit[SQLITE_LIMIT_LENGTH] ); |
| 1231 if( nOut-1>db->aLimit[SQLITE_LIMIT_LENGTH] ){ |
| 1232 sqlite3_result_error_toobig(context); |
| 1233 sqlite3_free(zOut); |
| 1234 return; |
| 1235 } |
| 1236 zOld = zOut; |
| 1237 zOut = sqlite3_realloc64(zOut, (int)nOut); |
| 1238 if( zOut==0 ){ |
| 1239 sqlite3_result_error_nomem(context); |
| 1240 sqlite3_free(zOld); |
| 1241 return; |
| 1242 } |
| 1243 memcpy(&zOut[j], zRep, nRep); |
| 1244 j += nRep; |
| 1245 i += nPattern-1; |
| 1246 } |
| 1247 } |
| 1248 assert( j+nStr-i+1==nOut ); |
| 1249 memcpy(&zOut[j], &zStr[i], nStr-i); |
| 1250 j += nStr - i; |
| 1251 assert( j<=nOut ); |
| 1252 zOut[j] = 0; |
| 1253 sqlite3_result_text(context, (char*)zOut, j, sqlite3_free); |
| 1254 } |
| 1255 |
| 1256 /* |
| 1257 ** Implementation of the TRIM(), LTRIM(), and RTRIM() functions. |
| 1258 ** The userdata is 0x1 for left trim, 0x2 for right trim, 0x3 for both. |
| 1259 */ |
| 1260 static void trimFunc( |
| 1261 sqlite3_context *context, |
| 1262 int argc, |
| 1263 sqlite3_value **argv |
| 1264 ){ |
| 1265 const unsigned char *zIn; /* Input string */ |
| 1266 const unsigned char *zCharSet; /* Set of characters to trim */ |
| 1267 int nIn; /* Number of bytes in input */ |
| 1268 int flags; /* 1: trimleft 2: trimright 3: trim */ |
| 1269 int i; /* Loop counter */ |
| 1270 unsigned char *aLen = 0; /* Length of each character in zCharSet */ |
| 1271 unsigned char **azChar = 0; /* Individual characters in zCharSet */ |
| 1272 int nChar; /* Number of characters in zCharSet */ |
| 1273 |
| 1274 if( sqlite3_value_type(argv[0])==SQLITE_NULL ){ |
| 1275 return; |
| 1276 } |
| 1277 zIn = sqlite3_value_text(argv[0]); |
| 1278 if( zIn==0 ) return; |
| 1279 nIn = sqlite3_value_bytes(argv[0]); |
| 1280 assert( zIn==sqlite3_value_text(argv[0]) ); |
| 1281 if( argc==1 ){ |
| 1282 static const unsigned char lenOne[] = { 1 }; |
| 1283 static unsigned char * const azOne[] = { (u8*)" " }; |
| 1284 nChar = 1; |
| 1285 aLen = (u8*)lenOne; |
| 1286 azChar = (unsigned char **)azOne; |
| 1287 zCharSet = 0; |
| 1288 }else if( (zCharSet = sqlite3_value_text(argv[1]))==0 ){ |
| 1289 return; |
| 1290 }else{ |
| 1291 const unsigned char *z; |
| 1292 for(z=zCharSet, nChar=0; *z; nChar++){ |
| 1293 SQLITE_SKIP_UTF8(z); |
| 1294 } |
| 1295 if( nChar>0 ){ |
| 1296 azChar = contextMalloc(context, ((i64)nChar)*(sizeof(char*)+1)); |
| 1297 if( azChar==0 ){ |
| 1298 return; |
| 1299 } |
| 1300 aLen = (unsigned char*)&azChar[nChar]; |
| 1301 for(z=zCharSet, nChar=0; *z; nChar++){ |
| 1302 azChar[nChar] = (unsigned char *)z; |
| 1303 SQLITE_SKIP_UTF8(z); |
| 1304 aLen[nChar] = (u8)(z - azChar[nChar]); |
| 1305 } |
| 1306 } |
| 1307 } |
| 1308 if( nChar>0 ){ |
| 1309 flags = SQLITE_PTR_TO_INT(sqlite3_user_data(context)); |
| 1310 if( flags & 1 ){ |
| 1311 while( nIn>0 ){ |
| 1312 int len = 0; |
| 1313 for(i=0; i<nChar; i++){ |
| 1314 len = aLen[i]; |
| 1315 if( len<=nIn && memcmp(zIn, azChar[i], len)==0 ) break; |
| 1316 } |
| 1317 if( i>=nChar ) break; |
| 1318 zIn += len; |
| 1319 nIn -= len; |
| 1320 } |
| 1321 } |
| 1322 if( flags & 2 ){ |
| 1323 while( nIn>0 ){ |
| 1324 int len = 0; |
| 1325 for(i=0; i<nChar; i++){ |
| 1326 len = aLen[i]; |
| 1327 if( len<=nIn && memcmp(&zIn[nIn-len],azChar[i],len)==0 ) break; |
| 1328 } |
| 1329 if( i>=nChar ) break; |
| 1330 nIn -= len; |
| 1331 } |
| 1332 } |
| 1333 if( zCharSet ){ |
| 1334 sqlite3_free(azChar); |
| 1335 } |
| 1336 } |
| 1337 sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT); |
| 1338 } |
| 1339 |
| 1340 |
| 1341 #ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION |
| 1342 /* |
| 1343 ** The "unknown" function is automatically substituted in place of |
| 1344 ** any unrecognized function name when doing an EXPLAIN or EXPLAIN QUERY PLAN |
| 1345 ** when the SQLITE_ENABLE_UNKNOWN_FUNCTION compile-time option is used. |
| 1346 ** When the "sqlite3" command-line shell is built using this functionality, |
| 1347 ** that allows an EXPLAIN or EXPLAIN QUERY PLAN for complex queries |
| 1348 ** involving application-defined functions to be examined in a generic |
| 1349 ** sqlite3 shell. |
| 1350 */ |
| 1351 static void unknownFunc( |
| 1352 sqlite3_context *context, |
| 1353 int argc, |
| 1354 sqlite3_value **argv |
| 1355 ){ |
| 1356 /* no-op */ |
| 1357 } |
| 1358 #endif /*SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION*/ |
| 1359 |
| 1360 |
| 1361 /* IMP: R-25361-16150 This function is omitted from SQLite by default. It |
| 1362 ** is only available if the SQLITE_SOUNDEX compile-time option is used |
| 1363 ** when SQLite is built. |
| 1364 */ |
| 1365 #ifdef SQLITE_SOUNDEX |
| 1366 /* |
| 1367 ** Compute the soundex encoding of a word. |
| 1368 ** |
| 1369 ** IMP: R-59782-00072 The soundex(X) function returns a string that is the |
| 1370 ** soundex encoding of the string X. |
| 1371 */ |
| 1372 static void soundexFunc( |
| 1373 sqlite3_context *context, |
| 1374 int argc, |
| 1375 sqlite3_value **argv |
| 1376 ){ |
| 1377 char zResult[8]; |
| 1378 const u8 *zIn; |
| 1379 int i, j; |
| 1380 static const unsigned char iCode[] = { |
| 1381 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 1382 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 1383 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 1384 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 1385 0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0, |
| 1386 1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0, |
| 1387 0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0, |
| 1388 1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0, |
| 1389 }; |
| 1390 assert( argc==1 ); |
| 1391 zIn = (u8*)sqlite3_value_text(argv[0]); |
| 1392 if( zIn==0 ) zIn = (u8*)""; |
| 1393 for(i=0; zIn[i] && !sqlite3Isalpha(zIn[i]); i++){} |
| 1394 if( zIn[i] ){ |
| 1395 u8 prevcode = iCode[zIn[i]&0x7f]; |
| 1396 zResult[0] = sqlite3Toupper(zIn[i]); |
| 1397 for(j=1; j<4 && zIn[i]; i++){ |
| 1398 int code = iCode[zIn[i]&0x7f]; |
| 1399 if( code>0 ){ |
| 1400 if( code!=prevcode ){ |
| 1401 prevcode = code; |
| 1402 zResult[j++] = code + '0'; |
| 1403 } |
| 1404 }else{ |
| 1405 prevcode = 0; |
| 1406 } |
| 1407 } |
| 1408 while( j<4 ){ |
| 1409 zResult[j++] = '0'; |
| 1410 } |
| 1411 zResult[j] = 0; |
| 1412 sqlite3_result_text(context, zResult, 4, SQLITE_TRANSIENT); |
| 1413 }else{ |
| 1414 /* IMP: R-64894-50321 The string "?000" is returned if the argument |
| 1415 ** is NULL or contains no ASCII alphabetic characters. */ |
| 1416 sqlite3_result_text(context, "?000", 4, SQLITE_STATIC); |
| 1417 } |
| 1418 } |
| 1419 #endif /* SQLITE_SOUNDEX */ |
| 1420 |
| 1421 #ifndef SQLITE_OMIT_LOAD_EXTENSION |
| 1422 /* |
| 1423 ** A function that loads a shared-library extension then returns NULL. |
| 1424 */ |
| 1425 static void loadExt(sqlite3_context *context, int argc, sqlite3_value **argv){ |
| 1426 const char *zFile = (const char *)sqlite3_value_text(argv[0]); |
| 1427 const char *zProc; |
| 1428 sqlite3 *db = sqlite3_context_db_handle(context); |
| 1429 char *zErrMsg = 0; |
| 1430 |
| 1431 /* Disallow the load_extension() SQL function unless the SQLITE_LoadExtFunc |
| 1432 ** flag is set. See the sqlite3_enable_load_extension() API. |
| 1433 */ |
| 1434 if( (db->flags & SQLITE_LoadExtFunc)==0 ){ |
| 1435 sqlite3_result_error(context, "not authorized", -1); |
| 1436 return; |
| 1437 } |
| 1438 |
| 1439 if( argc==2 ){ |
| 1440 zProc = (const char *)sqlite3_value_text(argv[1]); |
| 1441 }else{ |
| 1442 zProc = 0; |
| 1443 } |
| 1444 if( zFile && sqlite3_load_extension(db, zFile, zProc, &zErrMsg) ){ |
| 1445 sqlite3_result_error(context, zErrMsg, -1); |
| 1446 sqlite3_free(zErrMsg); |
| 1447 } |
| 1448 } |
| 1449 #endif |
| 1450 |
| 1451 |
| 1452 /* |
| 1453 ** An instance of the following structure holds the context of a |
| 1454 ** sum() or avg() aggregate computation. |
| 1455 */ |
| 1456 typedef struct SumCtx SumCtx; |
| 1457 struct SumCtx { |
| 1458 double rSum; /* Floating point sum */ |
| 1459 i64 iSum; /* Integer sum */ |
| 1460 i64 cnt; /* Number of elements summed */ |
| 1461 u8 overflow; /* True if integer overflow seen */ |
| 1462 u8 approx; /* True if non-integer value was input to the sum */ |
| 1463 }; |
| 1464 |
| 1465 /* |
| 1466 ** Routines used to compute the sum, average, and total. |
| 1467 ** |
| 1468 ** The SUM() function follows the (broken) SQL standard which means |
| 1469 ** that it returns NULL if it sums over no inputs. TOTAL returns |
| 1470 ** 0.0 in that case. In addition, TOTAL always returns a float where |
| 1471 ** SUM might return an integer if it never encounters a floating point |
| 1472 ** value. TOTAL never fails, but SUM might through an exception if |
| 1473 ** it overflows an integer. |
| 1474 */ |
| 1475 static void sumStep(sqlite3_context *context, int argc, sqlite3_value **argv){ |
| 1476 SumCtx *p; |
| 1477 int type; |
| 1478 assert( argc==1 ); |
| 1479 UNUSED_PARAMETER(argc); |
| 1480 p = sqlite3_aggregate_context(context, sizeof(*p)); |
| 1481 type = sqlite3_value_numeric_type(argv[0]); |
| 1482 if( p && type!=SQLITE_NULL ){ |
| 1483 p->cnt++; |
| 1484 if( type==SQLITE_INTEGER ){ |
| 1485 i64 v = sqlite3_value_int64(argv[0]); |
| 1486 p->rSum += v; |
| 1487 if( (p->approx|p->overflow)==0 && sqlite3AddInt64(&p->iSum, v) ){ |
| 1488 p->overflow = 1; |
| 1489 } |
| 1490 }else{ |
| 1491 p->rSum += sqlite3_value_double(argv[0]); |
| 1492 p->approx = 1; |
| 1493 } |
| 1494 } |
| 1495 } |
| 1496 static void sumFinalize(sqlite3_context *context){ |
| 1497 SumCtx *p; |
| 1498 p = sqlite3_aggregate_context(context, 0); |
| 1499 if( p && p->cnt>0 ){ |
| 1500 if( p->overflow ){ |
| 1501 sqlite3_result_error(context,"integer overflow",-1); |
| 1502 }else if( p->approx ){ |
| 1503 sqlite3_result_double(context, p->rSum); |
| 1504 }else{ |
| 1505 sqlite3_result_int64(context, p->iSum); |
| 1506 } |
| 1507 } |
| 1508 } |
| 1509 static void avgFinalize(sqlite3_context *context){ |
| 1510 SumCtx *p; |
| 1511 p = sqlite3_aggregate_context(context, 0); |
| 1512 if( p && p->cnt>0 ){ |
| 1513 sqlite3_result_double(context, p->rSum/(double)p->cnt); |
| 1514 } |
| 1515 } |
| 1516 static void totalFinalize(sqlite3_context *context){ |
| 1517 SumCtx *p; |
| 1518 p = sqlite3_aggregate_context(context, 0); |
| 1519 /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */ |
| 1520 sqlite3_result_double(context, p ? p->rSum : (double)0); |
| 1521 } |
| 1522 |
| 1523 /* |
| 1524 ** The following structure keeps track of state information for the |
| 1525 ** count() aggregate function. |
| 1526 */ |
| 1527 typedef struct CountCtx CountCtx; |
| 1528 struct CountCtx { |
| 1529 i64 n; |
| 1530 }; |
| 1531 |
| 1532 /* |
| 1533 ** Routines to implement the count() aggregate function. |
| 1534 */ |
| 1535 static void countStep(sqlite3_context *context, int argc, sqlite3_value **argv){ |
| 1536 CountCtx *p; |
| 1537 p = sqlite3_aggregate_context(context, sizeof(*p)); |
| 1538 if( (argc==0 || SQLITE_NULL!=sqlite3_value_type(argv[0])) && p ){ |
| 1539 p->n++; |
| 1540 } |
| 1541 |
| 1542 #ifndef SQLITE_OMIT_DEPRECATED |
| 1543 /* The sqlite3_aggregate_count() function is deprecated. But just to make |
| 1544 ** sure it still operates correctly, verify that its count agrees with our |
| 1545 ** internal count when using count(*) and when the total count can be |
| 1546 ** expressed as a 32-bit integer. */ |
| 1547 assert( argc==1 || p==0 || p->n>0x7fffffff |
| 1548 || p->n==sqlite3_aggregate_count(context) ); |
| 1549 #endif |
| 1550 } |
| 1551 static void countFinalize(sqlite3_context *context){ |
| 1552 CountCtx *p; |
| 1553 p = sqlite3_aggregate_context(context, 0); |
| 1554 sqlite3_result_int64(context, p ? p->n : 0); |
| 1555 } |
| 1556 |
| 1557 /* |
| 1558 ** Routines to implement min() and max() aggregate functions. |
| 1559 */ |
| 1560 static void minmaxStep( |
| 1561 sqlite3_context *context, |
| 1562 int NotUsed, |
| 1563 sqlite3_value **argv |
| 1564 ){ |
| 1565 Mem *pArg = (Mem *)argv[0]; |
| 1566 Mem *pBest; |
| 1567 UNUSED_PARAMETER(NotUsed); |
| 1568 |
| 1569 pBest = (Mem *)sqlite3_aggregate_context(context, sizeof(*pBest)); |
| 1570 if( !pBest ) return; |
| 1571 |
| 1572 if( sqlite3_value_type(argv[0])==SQLITE_NULL ){ |
| 1573 if( pBest->flags ) sqlite3SkipAccumulatorLoad(context); |
| 1574 }else if( pBest->flags ){ |
| 1575 int max; |
| 1576 int cmp; |
| 1577 CollSeq *pColl = sqlite3GetFuncCollSeq(context); |
| 1578 /* This step function is used for both the min() and max() aggregates, |
| 1579 ** the only difference between the two being that the sense of the |
| 1580 ** comparison is inverted. For the max() aggregate, the |
| 1581 ** sqlite3_user_data() function returns (void *)-1. For min() it |
| 1582 ** returns (void *)db, where db is the sqlite3* database pointer. |
| 1583 ** Therefore the next statement sets variable 'max' to 1 for the max() |
| 1584 ** aggregate, or 0 for min(). |
| 1585 */ |
| 1586 max = sqlite3_user_data(context)!=0; |
| 1587 cmp = sqlite3MemCompare(pBest, pArg, pColl); |
| 1588 if( (max && cmp<0) || (!max && cmp>0) ){ |
| 1589 sqlite3VdbeMemCopy(pBest, pArg); |
| 1590 }else{ |
| 1591 sqlite3SkipAccumulatorLoad(context); |
| 1592 } |
| 1593 }else{ |
| 1594 pBest->db = sqlite3_context_db_handle(context); |
| 1595 sqlite3VdbeMemCopy(pBest, pArg); |
| 1596 } |
| 1597 } |
| 1598 static void minMaxFinalize(sqlite3_context *context){ |
| 1599 sqlite3_value *pRes; |
| 1600 pRes = (sqlite3_value *)sqlite3_aggregate_context(context, 0); |
| 1601 if( pRes ){ |
| 1602 if( pRes->flags ){ |
| 1603 sqlite3_result_value(context, pRes); |
| 1604 } |
| 1605 sqlite3VdbeMemRelease(pRes); |
| 1606 } |
| 1607 } |
| 1608 |
| 1609 /* |
| 1610 ** group_concat(EXPR, ?SEPARATOR?) |
| 1611 */ |
| 1612 static void groupConcatStep( |
| 1613 sqlite3_context *context, |
| 1614 int argc, |
| 1615 sqlite3_value **argv |
| 1616 ){ |
| 1617 const char *zVal; |
| 1618 StrAccum *pAccum; |
| 1619 const char *zSep; |
| 1620 int nVal, nSep; |
| 1621 assert( argc==1 || argc==2 ); |
| 1622 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; |
| 1623 pAccum = (StrAccum*)sqlite3_aggregate_context(context, sizeof(*pAccum)); |
| 1624 |
| 1625 if( pAccum ){ |
| 1626 sqlite3 *db = sqlite3_context_db_handle(context); |
| 1627 int firstTerm = pAccum->mxAlloc==0; |
| 1628 pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH]; |
| 1629 if( !firstTerm ){ |
| 1630 if( argc==2 ){ |
| 1631 zSep = (char*)sqlite3_value_text(argv[1]); |
| 1632 nSep = sqlite3_value_bytes(argv[1]); |
| 1633 }else{ |
| 1634 zSep = ","; |
| 1635 nSep = 1; |
| 1636 } |
| 1637 if( zSep ) sqlite3StrAccumAppend(pAccum, zSep, nSep); |
| 1638 } |
| 1639 zVal = (char*)sqlite3_value_text(argv[0]); |
| 1640 nVal = sqlite3_value_bytes(argv[0]); |
| 1641 if( zVal ) sqlite3StrAccumAppend(pAccum, zVal, nVal); |
| 1642 } |
| 1643 } |
| 1644 static void groupConcatFinalize(sqlite3_context *context){ |
| 1645 StrAccum *pAccum; |
| 1646 pAccum = sqlite3_aggregate_context(context, 0); |
| 1647 if( pAccum ){ |
| 1648 if( pAccum->accError==STRACCUM_TOOBIG ){ |
| 1649 sqlite3_result_error_toobig(context); |
| 1650 }else if( pAccum->accError==STRACCUM_NOMEM ){ |
| 1651 sqlite3_result_error_nomem(context); |
| 1652 }else{ |
| 1653 sqlite3_result_text(context, sqlite3StrAccumFinish(pAccum), -1, |
| 1654 sqlite3_free); |
| 1655 } |
| 1656 } |
| 1657 } |
| 1658 |
| 1659 /* |
| 1660 ** This routine does per-connection function registration. Most |
| 1661 ** of the built-in functions above are part of the global function set. |
| 1662 ** This routine only deals with those that are not global. |
| 1663 */ |
| 1664 void sqlite3RegisterPerConnectionBuiltinFunctions(sqlite3 *db){ |
| 1665 int rc = sqlite3_overload_function(db, "MATCH", 2); |
| 1666 assert( rc==SQLITE_NOMEM || rc==SQLITE_OK ); |
| 1667 if( rc==SQLITE_NOMEM ){ |
| 1668 sqlite3OomFault(db); |
| 1669 } |
| 1670 } |
| 1671 |
| 1672 /* |
| 1673 ** Set the LIKEOPT flag on the 2-argument function with the given name. |
| 1674 */ |
| 1675 static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){ |
| 1676 FuncDef *pDef; |
| 1677 pDef = sqlite3FindFunction(db, zName, 2, SQLITE_UTF8, 0); |
| 1678 if( ALWAYS(pDef) ){ |
| 1679 pDef->funcFlags |= flagVal; |
| 1680 } |
| 1681 } |
| 1682 |
| 1683 /* |
| 1684 ** Register the built-in LIKE and GLOB functions. The caseSensitive |
| 1685 ** parameter determines whether or not the LIKE operator is case |
| 1686 ** sensitive. GLOB is always case sensitive. |
| 1687 */ |
| 1688 void sqlite3RegisterLikeFunctions(sqlite3 *db, int caseSensitive){ |
| 1689 struct compareInfo *pInfo; |
| 1690 if( caseSensitive ){ |
| 1691 pInfo = (struct compareInfo*)&likeInfoAlt; |
| 1692 }else{ |
| 1693 pInfo = (struct compareInfo*)&likeInfoNorm; |
| 1694 } |
| 1695 sqlite3CreateFunc(db, "like", 2, SQLITE_UTF8, pInfo, likeFunc, 0, 0, 0); |
| 1696 sqlite3CreateFunc(db, "like", 3, SQLITE_UTF8, pInfo, likeFunc, 0, 0, 0); |
| 1697 sqlite3CreateFunc(db, "glob", 2, SQLITE_UTF8, |
| 1698 (struct compareInfo*)&globInfo, likeFunc, 0, 0, 0); |
| 1699 setLikeOptFlag(db, "glob", SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE); |
| 1700 setLikeOptFlag(db, "like", |
| 1701 caseSensitive ? (SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE) : SQLITE_FUNC_LIKE); |
| 1702 } |
| 1703 |
| 1704 /* |
| 1705 ** pExpr points to an expression which implements a function. If |
| 1706 ** it is appropriate to apply the LIKE optimization to that function |
| 1707 ** then set aWc[0] through aWc[2] to the wildcard characters and |
| 1708 ** return TRUE. If the function is not a LIKE-style function then |
| 1709 ** return FALSE. |
| 1710 ** |
| 1711 ** *pIsNocase is set to true if uppercase and lowercase are equivalent for |
| 1712 ** the function (default for LIKE). If the function makes the distinction |
| 1713 ** between uppercase and lowercase (as does GLOB) then *pIsNocase is set to |
| 1714 ** false. |
| 1715 */ |
| 1716 int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){ |
| 1717 FuncDef *pDef; |
| 1718 if( pExpr->op!=TK_FUNCTION |
| 1719 || !pExpr->x.pList |
| 1720 || pExpr->x.pList->nExpr!=2 |
| 1721 ){ |
| 1722 return 0; |
| 1723 } |
| 1724 assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); |
| 1725 pDef = sqlite3FindFunction(db, pExpr->u.zToken, 2, SQLITE_UTF8, 0); |
| 1726 if( NEVER(pDef==0) || (pDef->funcFlags & SQLITE_FUNC_LIKE)==0 ){ |
| 1727 return 0; |
| 1728 } |
| 1729 |
| 1730 /* The memcpy() statement assumes that the wildcard characters are |
| 1731 ** the first three statements in the compareInfo structure. The |
| 1732 ** asserts() that follow verify that assumption |
| 1733 */ |
| 1734 memcpy(aWc, pDef->pUserData, 3); |
| 1735 assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll ); |
| 1736 assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne ); |
| 1737 assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet ); |
| 1738 *pIsNocase = (pDef->funcFlags & SQLITE_FUNC_CASE)==0; |
| 1739 return 1; |
| 1740 } |
| 1741 |
| 1742 /* |
| 1743 ** All of the FuncDef structures in the aBuiltinFunc[] array above |
| 1744 ** to the global function hash table. This occurs at start-time (as |
| 1745 ** a consequence of calling sqlite3_initialize()). |
| 1746 ** |
| 1747 ** After this routine runs |
| 1748 */ |
| 1749 void sqlite3RegisterBuiltinFunctions(void){ |
| 1750 /* |
| 1751 ** The following array holds FuncDef structures for all of the functions |
| 1752 ** defined in this file. |
| 1753 ** |
| 1754 ** The array cannot be constant since changes are made to the |
| 1755 ** FuncDef.pHash elements at start-time. The elements of this array |
| 1756 ** are read-only after initialization is complete. |
| 1757 ** |
| 1758 ** For peak efficiency, put the most frequently used function last. |
| 1759 */ |
| 1760 static FuncDef aBuiltinFunc[] = { |
| 1761 #ifdef SQLITE_SOUNDEX |
| 1762 FUNCTION(soundex, 1, 0, 0, soundexFunc ), |
| 1763 #endif |
| 1764 #ifndef SQLITE_OMIT_LOAD_EXTENSION |
| 1765 VFUNCTION(load_extension, 1, 0, 0, loadExt ), |
| 1766 VFUNCTION(load_extension, 2, 0, 0, loadExt ), |
| 1767 #endif |
| 1768 #if SQLITE_USER_AUTHENTICATION |
| 1769 FUNCTION(sqlite_crypt, 2, 0, 0, sqlite3CryptFunc ), |
| 1770 #endif |
| 1771 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS |
| 1772 DFUNCTION(sqlite_compileoption_used,1, 0, 0, compileoptionusedFunc ), |
| 1773 DFUNCTION(sqlite_compileoption_get, 1, 0, 0, compileoptiongetFunc ), |
| 1774 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ |
| 1775 FUNCTION2(unlikely, 1, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), |
| 1776 FUNCTION2(likelihood, 2, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), |
| 1777 FUNCTION2(likely, 1, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), |
| 1778 #ifdef SQLITE_DEBUG |
| 1779 FUNCTION2(affinity, 1, 0, 0, noopFunc, SQLITE_FUNC_AFFINITY), |
| 1780 #endif |
| 1781 FUNCTION(ltrim, 1, 1, 0, trimFunc ), |
| 1782 FUNCTION(ltrim, 2, 1, 0, trimFunc ), |
| 1783 FUNCTION(rtrim, 1, 2, 0, trimFunc ), |
| 1784 FUNCTION(rtrim, 2, 2, 0, trimFunc ), |
| 1785 FUNCTION(trim, 1, 3, 0, trimFunc ), |
| 1786 FUNCTION(trim, 2, 3, 0, trimFunc ), |
| 1787 FUNCTION(min, -1, 0, 1, minmaxFunc ), |
| 1788 FUNCTION(min, 0, 0, 1, 0 ), |
| 1789 AGGREGATE2(min, 1, 0, 1, minmaxStep, minMaxFinalize, |
| 1790 SQLITE_FUNC_MINMAX ), |
| 1791 FUNCTION(max, -1, 1, 1, minmaxFunc ), |
| 1792 FUNCTION(max, 0, 1, 1, 0 ), |
| 1793 AGGREGATE2(max, 1, 1, 1, minmaxStep, minMaxFinalize, |
| 1794 SQLITE_FUNC_MINMAX ), |
| 1795 FUNCTION2(typeof, 1, 0, 0, typeofFunc, SQLITE_FUNC_TYPEOF), |
| 1796 FUNCTION2(length, 1, 0, 0, lengthFunc, SQLITE_FUNC_LENGTH), |
| 1797 FUNCTION(instr, 2, 0, 0, instrFunc ), |
| 1798 FUNCTION(printf, -1, 0, 0, printfFunc ), |
| 1799 FUNCTION(unicode, 1, 0, 0, unicodeFunc ), |
| 1800 FUNCTION(char, -1, 0, 0, charFunc ), |
| 1801 FUNCTION(abs, 1, 0, 0, absFunc ), |
| 1802 #ifndef SQLITE_OMIT_FLOATING_POINT |
| 1803 FUNCTION(round, 1, 0, 0, roundFunc ), |
| 1804 FUNCTION(round, 2, 0, 0, roundFunc ), |
| 1805 #endif |
| 1806 FUNCTION(upper, 1, 0, 0, upperFunc ), |
| 1807 FUNCTION(lower, 1, 0, 0, lowerFunc ), |
| 1808 FUNCTION(hex, 1, 0, 0, hexFunc ), |
| 1809 FUNCTION2(ifnull, 2, 0, 0, noopFunc, SQLITE_FUNC_COALESCE), |
| 1810 VFUNCTION(random, 0, 0, 0, randomFunc ), |
| 1811 VFUNCTION(randomblob, 1, 0, 0, randomBlob ), |
| 1812 FUNCTION(nullif, 2, 0, 1, nullifFunc ), |
| 1813 DFUNCTION(sqlite_version, 0, 0, 0, versionFunc ), |
| 1814 DFUNCTION(sqlite_source_id, 0, 0, 0, sourceidFunc ), |
| 1815 FUNCTION(sqlite_log, 2, 0, 0, errlogFunc ), |
| 1816 FUNCTION(quote, 1, 0, 0, quoteFunc ), |
| 1817 VFUNCTION(last_insert_rowid, 0, 0, 0, last_insert_rowid), |
| 1818 VFUNCTION(changes, 0, 0, 0, changes ), |
| 1819 VFUNCTION(total_changes, 0, 0, 0, total_changes ), |
| 1820 FUNCTION(replace, 3, 0, 0, replaceFunc ), |
| 1821 FUNCTION(zeroblob, 1, 0, 0, zeroblobFunc ), |
| 1822 FUNCTION(substr, 2, 0, 0, substrFunc ), |
| 1823 FUNCTION(substr, 3, 0, 0, substrFunc ), |
| 1824 AGGREGATE(sum, 1, 0, 0, sumStep, sumFinalize ), |
| 1825 AGGREGATE(total, 1, 0, 0, sumStep, totalFinalize ), |
| 1826 AGGREGATE(avg, 1, 0, 0, sumStep, avgFinalize ), |
| 1827 AGGREGATE2(count, 0, 0, 0, countStep, countFinalize, |
| 1828 SQLITE_FUNC_COUNT ), |
| 1829 AGGREGATE(count, 1, 0, 0, countStep, countFinalize ), |
| 1830 AGGREGATE(group_concat, 1, 0, 0, groupConcatStep, groupConcatFinalize), |
| 1831 AGGREGATE(group_concat, 2, 0, 0, groupConcatStep, groupConcatFinalize), |
| 1832 |
| 1833 LIKEFUNC(glob, 2, &globInfo, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), |
| 1834 #ifdef SQLITE_CASE_SENSITIVE_LIKE |
| 1835 LIKEFUNC(like, 2, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), |
| 1836 LIKEFUNC(like, 3, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), |
| 1837 #else |
| 1838 LIKEFUNC(like, 2, &likeInfoNorm, SQLITE_FUNC_LIKE), |
| 1839 LIKEFUNC(like, 3, &likeInfoNorm, SQLITE_FUNC_LIKE), |
| 1840 #endif |
| 1841 #ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION |
| 1842 FUNCTION(unknown, -1, 0, 0, unknownFunc ), |
| 1843 #endif |
| 1844 FUNCTION(coalesce, 1, 0, 0, 0 ), |
| 1845 FUNCTION(coalesce, 0, 0, 0, 0 ), |
| 1846 FUNCTION2(coalesce, -1, 0, 0, noopFunc, SQLITE_FUNC_COALESCE), |
| 1847 }; |
| 1848 #ifndef SQLITE_OMIT_ALTERTABLE |
| 1849 sqlite3AlterFunctions(); |
| 1850 #endif |
| 1851 #if defined(SQLITE_ENABLE_STAT3) || defined(SQLITE_ENABLE_STAT4) |
| 1852 sqlite3AnalyzeFunctions(); |
| 1853 #endif |
| 1854 sqlite3RegisterDateTimeFunctions(); |
| 1855 sqlite3InsertBuiltinFuncs(aBuiltinFunc, ArraySize(aBuiltinFunc)); |
| 1856 |
| 1857 #if 0 /* Enable to print out how the built-in functions are hashed */ |
| 1858 { |
| 1859 int i; |
| 1860 FuncDef *p; |
| 1861 for(i=0; i<SQLITE_FUNC_HASH_SZ; i++){ |
| 1862 printf("FUNC-HASH %02d:", i); |
| 1863 for(p=sqlite3BuiltinFunctions.a[i]; p; p=p->u.pHash){ |
| 1864 int n = sqlite3Strlen30(p->zName); |
| 1865 int h = p->zName[0] + n; |
| 1866 printf(" %s(%d)", p->zName, h); |
| 1867 } |
| 1868 printf("\n"); |
| 1869 } |
| 1870 } |
| 1871 #endif |
| 1872 } |
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