| OLD | NEW |
|---|
| (Empty) |
| 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( typeHaystack==SQLITE_BLOB && typeNeedle==SQLITE_BLOB ){ | |
| 204 zHaystack = sqlite3_value_blob(argv[0]); | |
| 205 zNeedle = sqlite3_value_blob(argv[1]); | |
| 206 isText = 0; | |
| 207 }else{ | |
| 208 zHaystack = sqlite3_value_text(argv[0]); | |
| 209 zNeedle = sqlite3_value_text(argv[1]); | |
| 210 isText = 1; | |
| 211 } | |
| 212 while( nNeedle<=nHaystack && memcmp(zHaystack, zNeedle, nNeedle)!=0 ){ | |
| 213 N++; | |
| 214 do{ | |
| 215 nHaystack--; | |
| 216 zHaystack++; | |
| 217 }while( isText && (zHaystack[0]&0xc0)==0x80 ); | |
| 218 } | |
| 219 if( nNeedle>nHaystack ) N = 0; | |
| 220 sqlite3_result_int(context, N); | |
| 221 } | |
| 222 | |
| 223 /* | |
| 224 ** Implementation of the printf() function. | |
| 225 */ | |
| 226 static void printfFunc( | |
| 227 sqlite3_context *context, | |
| 228 int argc, | |
| 229 sqlite3_value **argv | |
| 230 ){ | |
| 231 PrintfArguments x; | |
| 232 StrAccum str; | |
| 233 const char *zFormat; | |
| 234 int n; | |
| 235 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 236 | |
| 237 if( argc>=1 && (zFormat = (const char*)sqlite3_value_text(argv[0]))!=0 ){ | |
| 238 x.nArg = argc-1; | |
| 239 x.nUsed = 0; | |
| 240 x.apArg = argv+1; | |
| 241 sqlite3StrAccumInit(&str, db, 0, 0, db->aLimit[SQLITE_LIMIT_LENGTH]); | |
| 242 sqlite3XPrintf(&str, SQLITE_PRINTF_SQLFUNC, zFormat, &x); | |
| 243 n = str.nChar; | |
| 244 sqlite3_result_text(context, sqlite3StrAccumFinish(&str), n, | |
| 245 SQLITE_DYNAMIC); | |
| 246 } | |
| 247 } | |
| 248 | |
| 249 /* | |
| 250 ** Implementation of the substr() function. | |
| 251 ** | |
| 252 ** substr(x,p1,p2) returns p2 characters of x[] beginning with p1. | |
| 253 ** p1 is 1-indexed. So substr(x,1,1) returns the first character | |
| 254 ** of x. If x is text, then we actually count UTF-8 characters. | |
| 255 ** If x is a blob, then we count bytes. | |
| 256 ** | |
| 257 ** If p1 is negative, then we begin abs(p1) from the end of x[]. | |
| 258 ** | |
| 259 ** If p2 is negative, return the p2 characters preceding p1. | |
| 260 */ | |
| 261 static void substrFunc( | |
| 262 sqlite3_context *context, | |
| 263 int argc, | |
| 264 sqlite3_value **argv | |
| 265 ){ | |
| 266 const unsigned char *z; | |
| 267 const unsigned char *z2; | |
| 268 int len; | |
| 269 int p0type; | |
| 270 i64 p1, p2; | |
| 271 int negP2 = 0; | |
| 272 | |
| 273 assert( argc==3 || argc==2 ); | |
| 274 if( sqlite3_value_type(argv[1])==SQLITE_NULL | |
| 275 || (argc==3 && sqlite3_value_type(argv[2])==SQLITE_NULL) | |
| 276 ){ | |
| 277 return; | |
| 278 } | |
| 279 p0type = sqlite3_value_type(argv[0]); | |
| 280 p1 = sqlite3_value_int(argv[1]); | |
| 281 if( p0type==SQLITE_BLOB ){ | |
| 282 len = sqlite3_value_bytes(argv[0]); | |
| 283 z = sqlite3_value_blob(argv[0]); | |
| 284 if( z==0 ) return; | |
| 285 assert( len==sqlite3_value_bytes(argv[0]) ); | |
| 286 }else{ | |
| 287 z = sqlite3_value_text(argv[0]); | |
| 288 if( z==0 ) return; | |
| 289 len = 0; | |
| 290 if( p1<0 ){ | |
| 291 for(z2=z; *z2; len++){ | |
| 292 SQLITE_SKIP_UTF8(z2); | |
| 293 } | |
| 294 } | |
| 295 } | |
| 296 #ifdef SQLITE_SUBSTR_COMPATIBILITY | |
| 297 /* If SUBSTR_COMPATIBILITY is defined then substr(X,0,N) work the same as | |
| 298 ** as substr(X,1,N) - it returns the first N characters of X. This | |
| 299 ** is essentially a back-out of the bug-fix in check-in [5fc125d362df4b8] | |
| 300 ** from 2009-02-02 for compatibility of applications that exploited the | |
| 301 ** old buggy behavior. */ | |
| 302 if( p1==0 ) p1 = 1; /* <rdar://problem/6778339> */ | |
| 303 #endif | |
| 304 if( argc==3 ){ | |
| 305 p2 = sqlite3_value_int(argv[2]); | |
| 306 if( p2<0 ){ | |
| 307 p2 = -p2; | |
| 308 negP2 = 1; | |
| 309 } | |
| 310 }else{ | |
| 311 p2 = sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH]; | |
| 312 } | |
| 313 if( p1<0 ){ | |
| 314 p1 += len; | |
| 315 if( p1<0 ){ | |
| 316 p2 += p1; | |
| 317 if( p2<0 ) p2 = 0; | |
| 318 p1 = 0; | |
| 319 } | |
| 320 }else if( p1>0 ){ | |
| 321 p1--; | |
| 322 }else if( p2>0 ){ | |
| 323 p2--; | |
| 324 } | |
| 325 if( negP2 ){ | |
| 326 p1 -= p2; | |
| 327 if( p1<0 ){ | |
| 328 p2 += p1; | |
| 329 p1 = 0; | |
| 330 } | |
| 331 } | |
| 332 assert( p1>=0 && p2>=0 ); | |
| 333 if( p0type!=SQLITE_BLOB ){ | |
| 334 while( *z && p1 ){ | |
| 335 SQLITE_SKIP_UTF8(z); | |
| 336 p1--; | |
| 337 } | |
| 338 for(z2=z; *z2 && p2; p2--){ | |
| 339 SQLITE_SKIP_UTF8(z2); | |
| 340 } | |
| 341 sqlite3_result_text64(context, (char*)z, z2-z, SQLITE_TRANSIENT, | |
| 342 SQLITE_UTF8); | |
| 343 }else{ | |
| 344 if( p1+p2>len ){ | |
| 345 p2 = len-p1; | |
| 346 if( p2<0 ) p2 = 0; | |
| 347 } | |
| 348 sqlite3_result_blob64(context, (char*)&z[p1], (u64)p2, SQLITE_TRANSIENT); | |
| 349 } | |
| 350 } | |
| 351 | |
| 352 /* | |
| 353 ** Implementation of the round() function | |
| 354 */ | |
| 355 #ifndef SQLITE_OMIT_FLOATING_POINT | |
| 356 static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ | |
| 357 int n = 0; | |
| 358 double r; | |
| 359 char *zBuf; | |
| 360 assert( argc==1 || argc==2 ); | |
| 361 if( argc==2 ){ | |
| 362 if( SQLITE_NULL==sqlite3_value_type(argv[1]) ) return; | |
| 363 n = sqlite3_value_int(argv[1]); | |
| 364 if( n>30 ) n = 30; | |
| 365 if( n<0 ) n = 0; | |
| 366 } | |
| 367 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; | |
| 368 r = sqlite3_value_double(argv[0]); | |
| 369 /* If Y==0 and X will fit in a 64-bit int, | |
| 370 ** handle the rounding directly, | |
| 371 ** otherwise use printf. | |
| 372 */ | |
| 373 if( n==0 && r>=0 && r<LARGEST_INT64-1 ){ | |
| 374 r = (double)((sqlite_int64)(r+0.5)); | |
| 375 }else if( n==0 && r<0 && (-r)<LARGEST_INT64-1 ){ | |
| 376 r = -(double)((sqlite_int64)((-r)+0.5)); | |
| 377 }else{ | |
| 378 zBuf = sqlite3_mprintf("%.*f",n,r); | |
| 379 if( zBuf==0 ){ | |
| 380 sqlite3_result_error_nomem(context); | |
| 381 return; | |
| 382 } | |
| 383 sqlite3AtoF(zBuf, &r, sqlite3Strlen30(zBuf), SQLITE_UTF8); | |
| 384 sqlite3_free(zBuf); | |
| 385 } | |
| 386 sqlite3_result_double(context, r); | |
| 387 } | |
| 388 #endif | |
| 389 | |
| 390 /* | |
| 391 ** Allocate nByte bytes of space using sqlite3Malloc(). If the | |
| 392 ** allocation fails, call sqlite3_result_error_nomem() to notify | |
| 393 ** the database handle that malloc() has failed and return NULL. | |
| 394 ** If nByte is larger than the maximum string or blob length, then | |
| 395 ** raise an SQLITE_TOOBIG exception and return NULL. | |
| 396 */ | |
| 397 static void *contextMalloc(sqlite3_context *context, i64 nByte){ | |
| 398 char *z; | |
| 399 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 400 assert( nByte>0 ); | |
| 401 testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH] ); | |
| 402 testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH]+1 ); | |
| 403 if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){ | |
| 404 sqlite3_result_error_toobig(context); | |
| 405 z = 0; | |
| 406 }else{ | |
| 407 z = sqlite3Malloc(nByte); | |
| 408 if( !z ){ | |
| 409 sqlite3_result_error_nomem(context); | |
| 410 } | |
| 411 } | |
| 412 return z; | |
| 413 } | |
| 414 | |
| 415 /* | |
| 416 ** Implementation of the upper() and lower() SQL functions. | |
| 417 */ | |
| 418 static void upperFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ | |
| 419 char *z1; | |
| 420 const char *z2; | |
| 421 int i, n; | |
| 422 UNUSED_PARAMETER(argc); | |
| 423 z2 = (char*)sqlite3_value_text(argv[0]); | |
| 424 n = sqlite3_value_bytes(argv[0]); | |
| 425 /* Verify that the call to _bytes() does not invalidate the _text() pointer */ | |
| 426 assert( z2==(char*)sqlite3_value_text(argv[0]) ); | |
| 427 if( z2 ){ | |
| 428 z1 = contextMalloc(context, ((i64)n)+1); | |
| 429 if( z1 ){ | |
| 430 for(i=0; i<n; i++){ | |
| 431 z1[i] = (char)sqlite3Toupper(z2[i]); | |
| 432 } | |
| 433 sqlite3_result_text(context, z1, n, sqlite3_free); | |
| 434 } | |
| 435 } | |
| 436 } | |
| 437 static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ | |
| 438 char *z1; | |
| 439 const char *z2; | |
| 440 int i, n; | |
| 441 UNUSED_PARAMETER(argc); | |
| 442 z2 = (char*)sqlite3_value_text(argv[0]); | |
| 443 n = sqlite3_value_bytes(argv[0]); | |
| 444 /* Verify that the call to _bytes() does not invalidate the _text() pointer */ | |
| 445 assert( z2==(char*)sqlite3_value_text(argv[0]) ); | |
| 446 if( z2 ){ | |
| 447 z1 = contextMalloc(context, ((i64)n)+1); | |
| 448 if( z1 ){ | |
| 449 for(i=0; i<n; i++){ | |
| 450 z1[i] = sqlite3Tolower(z2[i]); | |
| 451 } | |
| 452 sqlite3_result_text(context, z1, n, sqlite3_free); | |
| 453 } | |
| 454 } | |
| 455 } | |
| 456 | |
| 457 /* | |
| 458 ** Some functions like COALESCE() and IFNULL() and UNLIKELY() are implemented | |
| 459 ** as VDBE code so that unused argument values do not have to be computed. | |
| 460 ** However, we still need some kind of function implementation for this | |
| 461 ** routines in the function table. The noopFunc macro provides this. | |
| 462 ** noopFunc will never be called so it doesn't matter what the implementation | |
| 463 ** is. We might as well use the "version()" function as a substitute. | |
| 464 */ | |
| 465 #define noopFunc versionFunc /* Substitute function - never called */ | |
| 466 | |
| 467 /* | |
| 468 ** Implementation of random(). Return a random integer. | |
| 469 */ | |
| 470 static void randomFunc( | |
| 471 sqlite3_context *context, | |
| 472 int NotUsed, | |
| 473 sqlite3_value **NotUsed2 | |
| 474 ){ | |
| 475 sqlite_int64 r; | |
| 476 UNUSED_PARAMETER2(NotUsed, NotUsed2); | |
| 477 sqlite3_randomness(sizeof(r), &r); | |
| 478 if( r<0 ){ | |
| 479 /* We need to prevent a random number of 0x8000000000000000 | |
| 480 ** (or -9223372036854775808) since when you do abs() of that | |
| 481 ** number of you get the same value back again. To do this | |
| 482 ** in a way that is testable, mask the sign bit off of negative | |
| 483 ** values, resulting in a positive value. Then take the | |
| 484 ** 2s complement of that positive value. The end result can | |
| 485 ** therefore be no less than -9223372036854775807. | |
| 486 */ | |
| 487 r = -(r & LARGEST_INT64); | |
| 488 } | |
| 489 sqlite3_result_int64(context, r); | |
| 490 } | |
| 491 | |
| 492 /* | |
| 493 ** Implementation of randomblob(N). Return a random blob | |
| 494 ** that is N bytes long. | |
| 495 */ | |
| 496 static void randomBlob( | |
| 497 sqlite3_context *context, | |
| 498 int argc, | |
| 499 sqlite3_value **argv | |
| 500 ){ | |
| 501 int n; | |
| 502 unsigned char *p; | |
| 503 assert( argc==1 ); | |
| 504 UNUSED_PARAMETER(argc); | |
| 505 n = sqlite3_value_int(argv[0]); | |
| 506 if( n<1 ){ | |
| 507 n = 1; | |
| 508 } | |
| 509 p = contextMalloc(context, n); | |
| 510 if( p ){ | |
| 511 sqlite3_randomness(n, p); | |
| 512 sqlite3_result_blob(context, (char*)p, n, sqlite3_free); | |
| 513 } | |
| 514 } | |
| 515 | |
| 516 /* | |
| 517 ** Implementation of the last_insert_rowid() SQL function. The return | |
| 518 ** value is the same as the sqlite3_last_insert_rowid() API function. | |
| 519 */ | |
| 520 static void last_insert_rowid( | |
| 521 sqlite3_context *context, | |
| 522 int NotUsed, | |
| 523 sqlite3_value **NotUsed2 | |
| 524 ){ | |
| 525 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 526 UNUSED_PARAMETER2(NotUsed, NotUsed2); | |
| 527 /* IMP: R-51513-12026 The last_insert_rowid() SQL function is a | |
| 528 ** wrapper around the sqlite3_last_insert_rowid() C/C++ interface | |
| 529 ** function. */ | |
| 530 sqlite3_result_int64(context, sqlite3_last_insert_rowid(db)); | |
| 531 } | |
| 532 | |
| 533 /* | |
| 534 ** Implementation of the changes() SQL function. | |
| 535 ** | |
| 536 ** IMP: R-62073-11209 The changes() SQL function is a wrapper | |
| 537 ** around the sqlite3_changes() C/C++ function and hence follows the same | |
| 538 ** rules for counting changes. | |
| 539 */ | |
| 540 static void changes( | |
| 541 sqlite3_context *context, | |
| 542 int NotUsed, | |
| 543 sqlite3_value **NotUsed2 | |
| 544 ){ | |
| 545 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 546 UNUSED_PARAMETER2(NotUsed, NotUsed2); | |
| 547 sqlite3_result_int(context, sqlite3_changes(db)); | |
| 548 } | |
| 549 | |
| 550 /* | |
| 551 ** Implementation of the total_changes() SQL function. The return value is | |
| 552 ** the same as the sqlite3_total_changes() API function. | |
| 553 */ | |
| 554 static void total_changes( | |
| 555 sqlite3_context *context, | |
| 556 int NotUsed, | |
| 557 sqlite3_value **NotUsed2 | |
| 558 ){ | |
| 559 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 560 UNUSED_PARAMETER2(NotUsed, NotUsed2); | |
| 561 /* IMP: R-52756-41993 This function is a wrapper around the | |
| 562 ** sqlite3_total_changes() C/C++ interface. */ | |
| 563 sqlite3_result_int(context, sqlite3_total_changes(db)); | |
| 564 } | |
| 565 | |
| 566 /* | |
| 567 ** A structure defining how to do GLOB-style comparisons. | |
| 568 */ | |
| 569 struct compareInfo { | |
| 570 u8 matchAll; | |
| 571 u8 matchOne; | |
| 572 u8 matchSet; | |
| 573 u8 noCase; | |
| 574 }; | |
| 575 | |
| 576 /* | |
| 577 ** For LIKE and GLOB matching on EBCDIC machines, assume that every | |
| 578 ** character is exactly one byte in size. Also, provde the Utf8Read() | |
| 579 ** macro for fast reading of the next character in the common case where | |
| 580 ** the next character is ASCII. | |
| 581 */ | |
| 582 #if defined(SQLITE_EBCDIC) | |
| 583 # define sqlite3Utf8Read(A) (*((*A)++)) | |
| 584 # define Utf8Read(A) (*(A++)) | |
| 585 #else | |
| 586 # define Utf8Read(A) (A[0]<0x80?*(A++):sqlite3Utf8Read(&A)) | |
| 587 #endif | |
| 588 | |
| 589 static const struct compareInfo globInfo = { '*', '?', '[', 0 }; | |
| 590 /* The correct SQL-92 behavior is for the LIKE operator to ignore | |
| 591 ** case. Thus 'a' LIKE 'A' would be true. */ | |
| 592 static const struct compareInfo likeInfoNorm = { '%', '_', 0, 1 }; | |
| 593 /* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator | |
| 594 ** is case sensitive causing 'a' LIKE 'A' to be false */ | |
| 595 static const struct compareInfo likeInfoAlt = { '%', '_', 0, 0 }; | |
| 596 | |
| 597 /* | |
| 598 ** Compare two UTF-8 strings for equality where the first string can | |
| 599 ** potentially be a "glob" or "like" expression. Return true (1) if they | |
| 600 ** are the same and false (0) if they are different. | |
| 601 ** | |
| 602 ** Globbing rules: | |
| 603 ** | |
| 604 ** '*' Matches any sequence of zero or more characters. | |
| 605 ** | |
| 606 ** '?' Matches exactly one character. | |
| 607 ** | |
| 608 ** [...] Matches one character from the enclosed list of | |
| 609 ** characters. | |
| 610 ** | |
| 611 ** [^...] Matches one character not in the enclosed list. | |
| 612 ** | |
| 613 ** With the [...] and [^...] matching, a ']' character can be included | |
| 614 ** in the list by making it the first character after '[' or '^'. A | |
| 615 ** range of characters can be specified using '-'. Example: | |
| 616 ** "[a-z]" matches any single lower-case letter. To match a '-', make | |
| 617 ** it the last character in the list. | |
| 618 ** | |
| 619 ** Like matching rules: | |
| 620 ** | |
| 621 ** '%' Matches any sequence of zero or more characters | |
| 622 ** | |
| 623 *** '_' Matches any one character | |
| 624 ** | |
| 625 ** Ec Where E is the "esc" character and c is any other | |
| 626 ** character, including '%', '_', and esc, match exactly c. | |
| 627 ** | |
| 628 ** The comments within this routine usually assume glob matching. | |
| 629 ** | |
| 630 ** This routine is usually quick, but can be N**2 in the worst case. | |
| 631 */ | |
| 632 static int patternCompare( | |
| 633 const u8 *zPattern, /* The glob pattern */ | |
| 634 const u8 *zString, /* The string to compare against the glob */ | |
| 635 const struct compareInfo *pInfo, /* Information about how to do the compare */ | |
| 636 u32 esc /* The escape character */ | |
| 637 ){ | |
| 638 u32 c, c2; /* Next pattern and input string chars */ | |
| 639 u32 matchOne = pInfo->matchOne; /* "?" or "_" */ | |
| 640 u32 matchAll = pInfo->matchAll; /* "*" or "%" */ | |
| 641 u32 matchOther; /* "[" or the escape character */ | |
| 642 u8 noCase = pInfo->noCase; /* True if uppercase==lowercase */ | |
| 643 const u8 *zEscaped = 0; /* One past the last escaped input char */ | |
| 644 | |
| 645 /* The GLOB operator does not have an ESCAPE clause. And LIKE does not | |
| 646 ** have the matchSet operator. So we either have to look for one or | |
| 647 ** the other, never both. Hence the single variable matchOther is used | |
| 648 ** to store the one we have to look for. | |
| 649 */ | |
| 650 matchOther = esc ? esc : pInfo->matchSet; | |
| 651 | |
| 652 while( (c = Utf8Read(zPattern))!=0 ){ | |
| 653 if( c==matchAll ){ /* Match "*" */ | |
| 654 /* Skip over multiple "*" characters in the pattern. If there | |
| 655 ** are also "?" characters, skip those as well, but consume a | |
| 656 ** single character of the input string for each "?" skipped */ | |
| 657 while( (c=Utf8Read(zPattern)) == matchAll || c == matchOne ){ | |
| 658 if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){ | |
| 659 return 0; | |
| 660 } | |
| 661 } | |
| 662 if( c==0 ){ | |
| 663 return 1; /* "*" at the end of the pattern matches */ | |
| 664 }else if( c==matchOther ){ | |
| 665 if( esc ){ | |
| 666 c = sqlite3Utf8Read(&zPattern); | |
| 667 if( c==0 ) return 0; | |
| 668 }else{ | |
| 669 /* "[...]" immediately follows the "*". We have to do a slow | |
| 670 ** recursive search in this case, but it is an unusual case. */ | |
| 671 assert( matchOther<0x80 ); /* '[' is a single-byte character */ | |
| 672 while( *zString | |
| 673 && patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){ | |
| 674 SQLITE_SKIP_UTF8(zString); | |
| 675 } | |
| 676 return *zString!=0; | |
| 677 } | |
| 678 } | |
| 679 | |
| 680 /* At this point variable c contains the first character of the | |
| 681 ** pattern string past the "*". Search in the input string for the | |
| 682 ** first matching character and recursively contine the match from | |
| 683 ** that point. | |
| 684 ** | |
| 685 ** For a case-insensitive search, set variable cx to be the same as | |
| 686 ** c but in the other case and search the input string for either | |
| 687 ** c or cx. | |
| 688 */ | |
| 689 if( c<=0x80 ){ | |
| 690 u32 cx; | |
| 691 if( noCase ){ | |
| 692 cx = sqlite3Toupper(c); | |
| 693 c = sqlite3Tolower(c); | |
| 694 }else{ | |
| 695 cx = c; | |
| 696 } | |
| 697 while( (c2 = *(zString++))!=0 ){ | |
| 698 if( c2!=c && c2!=cx ) continue; | |
| 699 if( patternCompare(zPattern,zString,pInfo,esc) ) return 1; | |
| 700 } | |
| 701 }else{ | |
| 702 while( (c2 = Utf8Read(zString))!=0 ){ | |
| 703 if( c2!=c ) continue; | |
| 704 if( patternCompare(zPattern,zString,pInfo,esc) ) return 1; | |
| 705 } | |
| 706 } | |
| 707 return 0; | |
| 708 } | |
| 709 if( c==matchOther ){ | |
| 710 if( esc ){ | |
| 711 c = sqlite3Utf8Read(&zPattern); | |
| 712 if( c==0 ) return 0; | |
| 713 zEscaped = zPattern; | |
| 714 }else{ | |
| 715 u32 prior_c = 0; | |
| 716 int seen = 0; | |
| 717 int invert = 0; | |
| 718 c = sqlite3Utf8Read(&zString); | |
| 719 if( c==0 ) return 0; | |
| 720 c2 = sqlite3Utf8Read(&zPattern); | |
| 721 if( c2=='^' ){ | |
| 722 invert = 1; | |
| 723 c2 = sqlite3Utf8Read(&zPattern); | |
| 724 } | |
| 725 if( c2==']' ){ | |
| 726 if( c==']' ) seen = 1; | |
| 727 c2 = sqlite3Utf8Read(&zPattern); | |
| 728 } | |
| 729 while( c2 && c2!=']' ){ | |
| 730 if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){ | |
| 731 c2 = sqlite3Utf8Read(&zPattern); | |
| 732 if( c>=prior_c && c<=c2 ) seen = 1; | |
| 733 prior_c = 0; | |
| 734 }else{ | |
| 735 if( c==c2 ){ | |
| 736 seen = 1; | |
| 737 } | |
| 738 prior_c = c2; | |
| 739 } | |
| 740 c2 = sqlite3Utf8Read(&zPattern); | |
| 741 } | |
| 742 if( c2==0 || (seen ^ invert)==0 ){ | |
| 743 return 0; | |
| 744 } | |
| 745 continue; | |
| 746 } | |
| 747 } | |
| 748 c2 = Utf8Read(zString); | |
| 749 if( c==c2 ) continue; | |
| 750 if( noCase && c<0x80 && c2<0x80 && sqlite3Tolower(c)==sqlite3Tolower(c2) ){ | |
| 751 continue; | |
| 752 } | |
| 753 if( c==matchOne && zPattern!=zEscaped && c2!=0 ) continue; | |
| 754 return 0; | |
| 755 } | |
| 756 return *zString==0; | |
| 757 } | |
| 758 | |
| 759 /* | |
| 760 ** The sqlite3_strglob() interface. | |
| 761 */ | |
| 762 int sqlite3_strglob(const char *zGlobPattern, const char *zString){ | |
| 763 return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, 0)==0; | |
| 764 } | |
| 765 | |
| 766 /* | |
| 767 ** The sqlite3_strlike() interface. | |
| 768 */ | |
| 769 int sqlite3_strlike(const char *zPattern, const char *zStr, unsigned int esc){ | |
| 770 return patternCompare((u8*)zPattern, (u8*)zStr, &likeInfoNorm, esc)==0; | |
| 771 } | |
| 772 | |
| 773 /* | |
| 774 ** Count the number of times that the LIKE operator (or GLOB which is | |
| 775 ** just a variation of LIKE) gets called. This is used for testing | |
| 776 ** only. | |
| 777 */ | |
| 778 #ifdef SQLITE_TEST | |
| 779 int sqlite3_like_count = 0; | |
| 780 #endif | |
| 781 | |
| 782 | |
| 783 /* | |
| 784 ** Implementation of the like() SQL function. This function implements | |
| 785 ** the build-in LIKE operator. The first argument to the function is the | |
| 786 ** pattern and the second argument is the string. So, the SQL statements: | |
| 787 ** | |
| 788 ** A LIKE B | |
| 789 ** | |
| 790 ** is implemented as like(B,A). | |
| 791 ** | |
| 792 ** This same function (with a different compareInfo structure) computes | |
| 793 ** the GLOB operator. | |
| 794 */ | |
| 795 static void likeFunc( | |
| 796 sqlite3_context *context, | |
| 797 int argc, | |
| 798 sqlite3_value **argv | |
| 799 ){ | |
| 800 const unsigned char *zA, *zB; | |
| 801 u32 escape = 0; | |
| 802 int nPat; | |
| 803 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 804 | |
| 805 #ifdef SQLITE_LIKE_DOESNT_MATCH_BLOBS | |
| 806 if( sqlite3_value_type(argv[0])==SQLITE_BLOB | |
| 807 || sqlite3_value_type(argv[1])==SQLITE_BLOB | |
| 808 ){ | |
| 809 #ifdef SQLITE_TEST | |
| 810 sqlite3_like_count++; | |
| 811 #endif | |
| 812 sqlite3_result_int(context, 0); | |
| 813 return; | |
| 814 } | |
| 815 #endif | |
| 816 zB = sqlite3_value_text(argv[0]); | |
| 817 zA = sqlite3_value_text(argv[1]); | |
| 818 | |
| 819 /* Limit the length of the LIKE or GLOB pattern to avoid problems | |
| 820 ** of deep recursion and N*N behavior in patternCompare(). | |
| 821 */ | |
| 822 nPat = sqlite3_value_bytes(argv[0]); | |
| 823 testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ); | |
| 824 testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]+1 ); | |
| 825 if( nPat > db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ){ | |
| 826 sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1); | |
| 827 return; | |
| 828 } | |
| 829 assert( zB==sqlite3_value_text(argv[0]) ); /* Encoding did not change */ | |
| 830 | |
| 831 if( argc==3 ){ | |
| 832 /* The escape character string must consist of a single UTF-8 character. | |
| 833 ** Otherwise, return an error. | |
| 834 */ | |
| 835 const unsigned char *zEsc = sqlite3_value_text(argv[2]); | |
| 836 if( zEsc==0 ) return; | |
| 837 if( sqlite3Utf8CharLen((char*)zEsc, -1)!=1 ){ | |
| 838 sqlite3_result_error(context, | |
| 839 "ESCAPE expression must be a single character", -1); | |
| 840 return; | |
| 841 } | |
| 842 escape = sqlite3Utf8Read(&zEsc); | |
| 843 } | |
| 844 if( zA && zB ){ | |
| 845 struct compareInfo *pInfo = sqlite3_user_data(context); | |
| 846 #ifdef SQLITE_TEST | |
| 847 sqlite3_like_count++; | |
| 848 #endif | |
| 849 | |
| 850 sqlite3_result_int(context, patternCompare(zB, zA, pInfo, escape)); | |
| 851 } | |
| 852 } | |
| 853 | |
| 854 /* | |
| 855 ** Implementation of the NULLIF(x,y) function. The result is the first | |
| 856 ** argument if the arguments are different. The result is NULL if the | |
| 857 ** arguments are equal to each other. | |
| 858 */ | |
| 859 static void nullifFunc( | |
| 860 sqlite3_context *context, | |
| 861 int NotUsed, | |
| 862 sqlite3_value **argv | |
| 863 ){ | |
| 864 CollSeq *pColl = sqlite3GetFuncCollSeq(context); | |
| 865 UNUSED_PARAMETER(NotUsed); | |
| 866 if( sqlite3MemCompare(argv[0], argv[1], pColl)!=0 ){ | |
| 867 sqlite3_result_value(context, argv[0]); | |
| 868 } | |
| 869 } | |
| 870 | |
| 871 /* | |
| 872 ** Implementation of the sqlite_version() function. The result is the version | |
| 873 ** of the SQLite library that is running. | |
| 874 */ | |
| 875 static void versionFunc( | |
| 876 sqlite3_context *context, | |
| 877 int NotUsed, | |
| 878 sqlite3_value **NotUsed2 | |
| 879 ){ | |
| 880 UNUSED_PARAMETER2(NotUsed, NotUsed2); | |
| 881 /* IMP: R-48699-48617 This function is an SQL wrapper around the | |
| 882 ** sqlite3_libversion() C-interface. */ | |
| 883 sqlite3_result_text(context, sqlite3_libversion(), -1, SQLITE_STATIC); | |
| 884 } | |
| 885 | |
| 886 /* | |
| 887 ** Implementation of the sqlite_source_id() function. The result is a string | |
| 888 ** that identifies the particular version of the source code used to build | |
| 889 ** SQLite. | |
| 890 */ | |
| 891 static void sourceidFunc( | |
| 892 sqlite3_context *context, | |
| 893 int NotUsed, | |
| 894 sqlite3_value **NotUsed2 | |
| 895 ){ | |
| 896 UNUSED_PARAMETER2(NotUsed, NotUsed2); | |
| 897 /* IMP: R-24470-31136 This function is an SQL wrapper around the | |
| 898 ** sqlite3_sourceid() C interface. */ | |
| 899 sqlite3_result_text(context, sqlite3_sourceid(), -1, SQLITE_STATIC); | |
| 900 } | |
| 901 | |
| 902 /* | |
| 903 ** Implementation of the sqlite_log() function. This is a wrapper around | |
| 904 ** sqlite3_log(). The return value is NULL. The function exists purely for | |
| 905 ** its side-effects. | |
| 906 */ | |
| 907 static void errlogFunc( | |
| 908 sqlite3_context *context, | |
| 909 int argc, | |
| 910 sqlite3_value **argv | |
| 911 ){ | |
| 912 UNUSED_PARAMETER(argc); | |
| 913 UNUSED_PARAMETER(context); | |
| 914 sqlite3_log(sqlite3_value_int(argv[0]), "%s", sqlite3_value_text(argv[1])); | |
| 915 } | |
| 916 | |
| 917 /* | |
| 918 ** Implementation of the sqlite_compileoption_used() function. | |
| 919 ** The result is an integer that identifies if the compiler option | |
| 920 ** was used to build SQLite. | |
| 921 */ | |
| 922 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS | |
| 923 static void compileoptionusedFunc( | |
| 924 sqlite3_context *context, | |
| 925 int argc, | |
| 926 sqlite3_value **argv | |
| 927 ){ | |
| 928 const char *zOptName; | |
| 929 assert( argc==1 ); | |
| 930 UNUSED_PARAMETER(argc); | |
| 931 /* IMP: R-39564-36305 The sqlite_compileoption_used() SQL | |
| 932 ** function is a wrapper around the sqlite3_compileoption_used() C/C++ | |
| 933 ** function. | |
| 934 */ | |
| 935 if( (zOptName = (const char*)sqlite3_value_text(argv[0]))!=0 ){ | |
| 936 sqlite3_result_int(context, sqlite3_compileoption_used(zOptName)); | |
| 937 } | |
| 938 } | |
| 939 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ | |
| 940 | |
| 941 /* | |
| 942 ** Implementation of the sqlite_compileoption_get() function. | |
| 943 ** The result is a string that identifies the compiler options | |
| 944 ** used to build SQLite. | |
| 945 */ | |
| 946 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS | |
| 947 static void compileoptiongetFunc( | |
| 948 sqlite3_context *context, | |
| 949 int argc, | |
| 950 sqlite3_value **argv | |
| 951 ){ | |
| 952 int n; | |
| 953 assert( argc==1 ); | |
| 954 UNUSED_PARAMETER(argc); | |
| 955 /* IMP: R-04922-24076 The sqlite_compileoption_get() SQL function | |
| 956 ** is a wrapper around the sqlite3_compileoption_get() C/C++ function. | |
| 957 */ | |
| 958 n = sqlite3_value_int(argv[0]); | |
| 959 sqlite3_result_text(context, sqlite3_compileoption_get(n), -1, SQLITE_STATIC); | |
| 960 } | |
| 961 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ | |
| 962 | |
| 963 /* Array for converting from half-bytes (nybbles) into ASCII hex | |
| 964 ** digits. */ | |
| 965 static const char hexdigits[] = { | |
| 966 '0', '1', '2', '3', '4', '5', '6', '7', | |
| 967 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' | |
| 968 }; | |
| 969 | |
| 970 /* | |
| 971 ** Implementation of the QUOTE() function. This function takes a single | |
| 972 ** argument. If the argument is numeric, the return value is the same as | |
| 973 ** the argument. If the argument is NULL, the return value is the string | |
| 974 ** "NULL". Otherwise, the argument is enclosed in single quotes with | |
| 975 ** single-quote escapes. | |
| 976 */ | |
| 977 static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){ | |
| 978 assert( argc==1 ); | |
| 979 UNUSED_PARAMETER(argc); | |
| 980 switch( sqlite3_value_type(argv[0]) ){ | |
| 981 case SQLITE_FLOAT: { | |
| 982 double r1, r2; | |
| 983 char zBuf[50]; | |
| 984 r1 = sqlite3_value_double(argv[0]); | |
| 985 sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.15g", r1); | |
| 986 sqlite3AtoF(zBuf, &r2, 20, SQLITE_UTF8); | |
| 987 if( r1!=r2 ){ | |
| 988 sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.20e", r1); | |
| 989 } | |
| 990 sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT); | |
| 991 break; | |
| 992 } | |
| 993 case SQLITE_INTEGER: { | |
| 994 sqlite3_result_value(context, argv[0]); | |
| 995 break; | |
| 996 } | |
| 997 case SQLITE_BLOB: { | |
| 998 char *zText = 0; | |
| 999 char const *zBlob = sqlite3_value_blob(argv[0]); | |
| 1000 int nBlob = sqlite3_value_bytes(argv[0]); | |
| 1001 assert( zBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */ | |
| 1002 zText = (char *)contextMalloc(context, (2*(i64)nBlob)+4); | |
| 1003 if( zText ){ | |
| 1004 int i; | |
| 1005 for(i=0; i<nBlob; i++){ | |
| 1006 zText[(i*2)+2] = hexdigits[(zBlob[i]>>4)&0x0F]; | |
| 1007 zText[(i*2)+3] = hexdigits[(zBlob[i])&0x0F]; | |
| 1008 } | |
| 1009 zText[(nBlob*2)+2] = '\''; | |
| 1010 zText[(nBlob*2)+3] = '\0'; | |
| 1011 zText[0] = 'X'; | |
| 1012 zText[1] = '\''; | |
| 1013 sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT); | |
| 1014 sqlite3_free(zText); | |
| 1015 } | |
| 1016 break; | |
| 1017 } | |
| 1018 case SQLITE_TEXT: { | |
| 1019 int i,j; | |
| 1020 u64 n; | |
| 1021 const unsigned char *zArg = sqlite3_value_text(argv[0]); | |
| 1022 char *z; | |
| 1023 | |
| 1024 if( zArg==0 ) return; | |
| 1025 for(i=0, n=0; zArg[i]; i++){ if( zArg[i]=='\'' ) n++; } | |
| 1026 z = contextMalloc(context, ((i64)i)+((i64)n)+3); | |
| 1027 if( z ){ | |
| 1028 z[0] = '\''; | |
| 1029 for(i=0, j=1; zArg[i]; i++){ | |
| 1030 z[j++] = zArg[i]; | |
| 1031 if( zArg[i]=='\'' ){ | |
| 1032 z[j++] = '\''; | |
| 1033 } | |
| 1034 } | |
| 1035 z[j++] = '\''; | |
| 1036 z[j] = 0; | |
| 1037 sqlite3_result_text(context, z, j, sqlite3_free); | |
| 1038 } | |
| 1039 break; | |
| 1040 } | |
| 1041 default: { | |
| 1042 assert( sqlite3_value_type(argv[0])==SQLITE_NULL ); | |
| 1043 sqlite3_result_text(context, "NULL", 4, SQLITE_STATIC); | |
| 1044 break; | |
| 1045 } | |
| 1046 } | |
| 1047 } | |
| 1048 | |
| 1049 /* | |
| 1050 ** The unicode() function. Return the integer unicode code-point value | |
| 1051 ** for the first character of the input string. | |
| 1052 */ | |
| 1053 static void unicodeFunc( | |
| 1054 sqlite3_context *context, | |
| 1055 int argc, | |
| 1056 sqlite3_value **argv | |
| 1057 ){ | |
| 1058 const unsigned char *z = sqlite3_value_text(argv[0]); | |
| 1059 (void)argc; | |
| 1060 if( z && z[0] ) sqlite3_result_int(context, sqlite3Utf8Read(&z)); | |
| 1061 } | |
| 1062 | |
| 1063 /* | |
| 1064 ** The char() function takes zero or more arguments, each of which is | |
| 1065 ** an integer. It constructs a string where each character of the string | |
| 1066 ** is the unicode character for the corresponding integer argument. | |
| 1067 */ | |
| 1068 static void charFunc( | |
| 1069 sqlite3_context *context, | |
| 1070 int argc, | |
| 1071 sqlite3_value **argv | |
| 1072 ){ | |
| 1073 unsigned char *z, *zOut; | |
| 1074 int i; | |
| 1075 zOut = z = sqlite3_malloc64( argc*4+1 ); | |
| 1076 if( z==0 ){ | |
| 1077 sqlite3_result_error_nomem(context); | |
| 1078 return; | |
| 1079 } | |
| 1080 for(i=0; i<argc; i++){ | |
| 1081 sqlite3_int64 x; | |
| 1082 unsigned c; | |
| 1083 x = sqlite3_value_int64(argv[i]); | |
| 1084 if( x<0 || x>0x10ffff ) x = 0xfffd; | |
| 1085 c = (unsigned)(x & 0x1fffff); | |
| 1086 if( c<0x00080 ){ | |
| 1087 *zOut++ = (u8)(c&0xFF); | |
| 1088 }else if( c<0x00800 ){ | |
| 1089 *zOut++ = 0xC0 + (u8)((c>>6)&0x1F); | |
| 1090 *zOut++ = 0x80 + (u8)(c & 0x3F); | |
| 1091 }else if( c<0x10000 ){ | |
| 1092 *zOut++ = 0xE0 + (u8)((c>>12)&0x0F); | |
| 1093 *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); | |
| 1094 *zOut++ = 0x80 + (u8)(c & 0x3F); | |
| 1095 }else{ | |
| 1096 *zOut++ = 0xF0 + (u8)((c>>18) & 0x07); | |
| 1097 *zOut++ = 0x80 + (u8)((c>>12) & 0x3F); | |
| 1098 *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); | |
| 1099 *zOut++ = 0x80 + (u8)(c & 0x3F); | |
| 1100 } \ | |
| 1101 } | |
| 1102 sqlite3_result_text64(context, (char*)z, zOut-z, sqlite3_free, SQLITE_UTF8); | |
| 1103 } | |
| 1104 | |
| 1105 /* | |
| 1106 ** The hex() function. Interpret the argument as a blob. Return | |
| 1107 ** a hexadecimal rendering as text. | |
| 1108 */ | |
| 1109 static void hexFunc( | |
| 1110 sqlite3_context *context, | |
| 1111 int argc, | |
| 1112 sqlite3_value **argv | |
| 1113 ){ | |
| 1114 int i, n; | |
| 1115 const unsigned char *pBlob; | |
| 1116 char *zHex, *z; | |
| 1117 assert( argc==1 ); | |
| 1118 UNUSED_PARAMETER(argc); | |
| 1119 pBlob = sqlite3_value_blob(argv[0]); | |
| 1120 n = sqlite3_value_bytes(argv[0]); | |
| 1121 assert( pBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */ | |
| 1122 z = zHex = contextMalloc(context, ((i64)n)*2 + 1); | |
| 1123 if( zHex ){ | |
| 1124 for(i=0; i<n; i++, pBlob++){ | |
| 1125 unsigned char c = *pBlob; | |
| 1126 *(z++) = hexdigits[(c>>4)&0xf]; | |
| 1127 *(z++) = hexdigits[c&0xf]; | |
| 1128 } | |
| 1129 *z = 0; | |
| 1130 sqlite3_result_text(context, zHex, n*2, sqlite3_free); | |
| 1131 } | |
| 1132 } | |
| 1133 | |
| 1134 /* | |
| 1135 ** The zeroblob(N) function returns a zero-filled blob of size N bytes. | |
| 1136 */ | |
| 1137 static void zeroblobFunc( | |
| 1138 sqlite3_context *context, | |
| 1139 int argc, | |
| 1140 sqlite3_value **argv | |
| 1141 ){ | |
| 1142 i64 n; | |
| 1143 int rc; | |
| 1144 assert( argc==1 ); | |
| 1145 UNUSED_PARAMETER(argc); | |
| 1146 n = sqlite3_value_int64(argv[0]); | |
| 1147 if( n<0 ) n = 0; | |
| 1148 rc = sqlite3_result_zeroblob64(context, n); /* IMP: R-00293-64994 */ | |
| 1149 if( rc ){ | |
| 1150 sqlite3_result_error_code(context, rc); | |
| 1151 } | |
| 1152 } | |
| 1153 | |
| 1154 /* | |
| 1155 ** The replace() function. Three arguments are all strings: call | |
| 1156 ** them A, B, and C. The result is also a string which is derived | |
| 1157 ** from A by replacing every occurrence of B with C. The match | |
| 1158 ** must be exact. Collating sequences are not used. | |
| 1159 */ | |
| 1160 static void replaceFunc( | |
| 1161 sqlite3_context *context, | |
| 1162 int argc, | |
| 1163 sqlite3_value **argv | |
| 1164 ){ | |
| 1165 const unsigned char *zStr; /* The input string A */ | |
| 1166 const unsigned char *zPattern; /* The pattern string B */ | |
| 1167 const unsigned char *zRep; /* The replacement string C */ | |
| 1168 unsigned char *zOut; /* The output */ | |
| 1169 int nStr; /* Size of zStr */ | |
| 1170 int nPattern; /* Size of zPattern */ | |
| 1171 int nRep; /* Size of zRep */ | |
| 1172 i64 nOut; /* Maximum size of zOut */ | |
| 1173 int loopLimit; /* Last zStr[] that might match zPattern[] */ | |
| 1174 int i, j; /* Loop counters */ | |
| 1175 | |
| 1176 assert( argc==3 ); | |
| 1177 UNUSED_PARAMETER(argc); | |
| 1178 zStr = sqlite3_value_text(argv[0]); | |
| 1179 if( zStr==0 ) return; | |
| 1180 nStr = sqlite3_value_bytes(argv[0]); | |
| 1181 assert( zStr==sqlite3_value_text(argv[0]) ); /* No encoding change */ | |
| 1182 zPattern = sqlite3_value_text(argv[1]); | |
| 1183 if( zPattern==0 ){ | |
| 1184 assert( sqlite3_value_type(argv[1])==SQLITE_NULL | |
| 1185 || sqlite3_context_db_handle(context)->mallocFailed ); | |
| 1186 return; | |
| 1187 } | |
| 1188 if( zPattern[0]==0 ){ | |
| 1189 assert( sqlite3_value_type(argv[1])!=SQLITE_NULL ); | |
| 1190 sqlite3_result_value(context, argv[0]); | |
| 1191 return; | |
| 1192 } | |
| 1193 nPattern = sqlite3_value_bytes(argv[1]); | |
| 1194 assert( zPattern==sqlite3_value_text(argv[1]) ); /* No encoding change */ | |
| 1195 zRep = sqlite3_value_text(argv[2]); | |
| 1196 if( zRep==0 ) return; | |
| 1197 nRep = sqlite3_value_bytes(argv[2]); | |
| 1198 assert( zRep==sqlite3_value_text(argv[2]) ); | |
| 1199 nOut = nStr + 1; | |
| 1200 assert( nOut<SQLITE_MAX_LENGTH ); | |
| 1201 zOut = contextMalloc(context, (i64)nOut); | |
| 1202 if( zOut==0 ){ | |
| 1203 return; | |
| 1204 } | |
| 1205 loopLimit = nStr - nPattern; | |
| 1206 for(i=j=0; i<=loopLimit; i++){ | |
| 1207 if( zStr[i]!=zPattern[0] || memcmp(&zStr[i], zPattern, nPattern) ){ | |
| 1208 zOut[j++] = zStr[i]; | |
| 1209 }else{ | |
| 1210 u8 *zOld; | |
| 1211 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 1212 nOut += nRep - nPattern; | |
| 1213 testcase( nOut-1==db->aLimit[SQLITE_LIMIT_LENGTH] ); | |
| 1214 testcase( nOut-2==db->aLimit[SQLITE_LIMIT_LENGTH] ); | |
| 1215 if( nOut-1>db->aLimit[SQLITE_LIMIT_LENGTH] ){ | |
| 1216 sqlite3_result_error_toobig(context); | |
| 1217 sqlite3_free(zOut); | |
| 1218 return; | |
| 1219 } | |
| 1220 zOld = zOut; | |
| 1221 zOut = sqlite3_realloc64(zOut, (int)nOut); | |
| 1222 if( zOut==0 ){ | |
| 1223 sqlite3_result_error_nomem(context); | |
| 1224 sqlite3_free(zOld); | |
| 1225 return; | |
| 1226 } | |
| 1227 memcpy(&zOut[j], zRep, nRep); | |
| 1228 j += nRep; | |
| 1229 i += nPattern-1; | |
| 1230 } | |
| 1231 } | |
| 1232 assert( j+nStr-i+1==nOut ); | |
| 1233 memcpy(&zOut[j], &zStr[i], nStr-i); | |
| 1234 j += nStr - i; | |
| 1235 assert( j<=nOut ); | |
| 1236 zOut[j] = 0; | |
| 1237 sqlite3_result_text(context, (char*)zOut, j, sqlite3_free); | |
| 1238 } | |
| 1239 | |
| 1240 /* | |
| 1241 ** Implementation of the TRIM(), LTRIM(), and RTRIM() functions. | |
| 1242 ** The userdata is 0x1 for left trim, 0x2 for right trim, 0x3 for both. | |
| 1243 */ | |
| 1244 static void trimFunc( | |
| 1245 sqlite3_context *context, | |
| 1246 int argc, | |
| 1247 sqlite3_value **argv | |
| 1248 ){ | |
| 1249 const unsigned char *zIn; /* Input string */ | |
| 1250 const unsigned char *zCharSet; /* Set of characters to trim */ | |
| 1251 int nIn; /* Number of bytes in input */ | |
| 1252 int flags; /* 1: trimleft 2: trimright 3: trim */ | |
| 1253 int i; /* Loop counter */ | |
| 1254 unsigned char *aLen = 0; /* Length of each character in zCharSet */ | |
| 1255 unsigned char **azChar = 0; /* Individual characters in zCharSet */ | |
| 1256 int nChar; /* Number of characters in zCharSet */ | |
| 1257 | |
| 1258 if( sqlite3_value_type(argv[0])==SQLITE_NULL ){ | |
| 1259 return; | |
| 1260 } | |
| 1261 zIn = sqlite3_value_text(argv[0]); | |
| 1262 if( zIn==0 ) return; | |
| 1263 nIn = sqlite3_value_bytes(argv[0]); | |
| 1264 assert( zIn==sqlite3_value_text(argv[0]) ); | |
| 1265 if( argc==1 ){ | |
| 1266 static const unsigned char lenOne[] = { 1 }; | |
| 1267 static unsigned char * const azOne[] = { (u8*)" " }; | |
| 1268 nChar = 1; | |
| 1269 aLen = (u8*)lenOne; | |
| 1270 azChar = (unsigned char **)azOne; | |
| 1271 zCharSet = 0; | |
| 1272 }else if( (zCharSet = sqlite3_value_text(argv[1]))==0 ){ | |
| 1273 return; | |
| 1274 }else{ | |
| 1275 const unsigned char *z; | |
| 1276 for(z=zCharSet, nChar=0; *z; nChar++){ | |
| 1277 SQLITE_SKIP_UTF8(z); | |
| 1278 } | |
| 1279 if( nChar>0 ){ | |
| 1280 azChar = contextMalloc(context, ((i64)nChar)*(sizeof(char*)+1)); | |
| 1281 if( azChar==0 ){ | |
| 1282 return; | |
| 1283 } | |
| 1284 aLen = (unsigned char*)&azChar[nChar]; | |
| 1285 for(z=zCharSet, nChar=0; *z; nChar++){ | |
| 1286 azChar[nChar] = (unsigned char *)z; | |
| 1287 SQLITE_SKIP_UTF8(z); | |
| 1288 aLen[nChar] = (u8)(z - azChar[nChar]); | |
| 1289 } | |
| 1290 } | |
| 1291 } | |
| 1292 if( nChar>0 ){ | |
| 1293 flags = SQLITE_PTR_TO_INT(sqlite3_user_data(context)); | |
| 1294 if( flags & 1 ){ | |
| 1295 while( nIn>0 ){ | |
| 1296 int len = 0; | |
| 1297 for(i=0; i<nChar; i++){ | |
| 1298 len = aLen[i]; | |
| 1299 if( len<=nIn && memcmp(zIn, azChar[i], len)==0 ) break; | |
| 1300 } | |
| 1301 if( i>=nChar ) break; | |
| 1302 zIn += len; | |
| 1303 nIn -= len; | |
| 1304 } | |
| 1305 } | |
| 1306 if( flags & 2 ){ | |
| 1307 while( nIn>0 ){ | |
| 1308 int len = 0; | |
| 1309 for(i=0; i<nChar; i++){ | |
| 1310 len = aLen[i]; | |
| 1311 if( len<=nIn && memcmp(&zIn[nIn-len],azChar[i],len)==0 ) break; | |
| 1312 } | |
| 1313 if( i>=nChar ) break; | |
| 1314 nIn -= len; | |
| 1315 } | |
| 1316 } | |
| 1317 if( zCharSet ){ | |
| 1318 sqlite3_free(azChar); | |
| 1319 } | |
| 1320 } | |
| 1321 sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT); | |
| 1322 } | |
| 1323 | |
| 1324 | |
| 1325 /* IMP: R-25361-16150 This function is omitted from SQLite by default. It | |
| 1326 ** is only available if the SQLITE_SOUNDEX compile-time option is used | |
| 1327 ** when SQLite is built. | |
| 1328 */ | |
| 1329 #ifdef SQLITE_SOUNDEX | |
| 1330 /* | |
| 1331 ** Compute the soundex encoding of a word. | |
| 1332 ** | |
| 1333 ** IMP: R-59782-00072 The soundex(X) function returns a string that is the | |
| 1334 ** soundex encoding of the string X. | |
| 1335 */ | |
| 1336 static void soundexFunc( | |
| 1337 sqlite3_context *context, | |
| 1338 int argc, | |
| 1339 sqlite3_value **argv | |
| 1340 ){ | |
| 1341 char zResult[8]; | |
| 1342 const u8 *zIn; | |
| 1343 int i, j; | |
| 1344 static const unsigned char iCode[] = { | |
| 1345 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | |
| 1346 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | |
| 1347 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | |
| 1348 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | |
| 1349 0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0, | |
| 1350 1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0, | |
| 1351 0, 0, 1, 2, 3, 0, 1, 2, 0, 0, 2, 2, 4, 5, 5, 0, | |
| 1352 1, 2, 6, 2, 3, 0, 1, 0, 2, 0, 2, 0, 0, 0, 0, 0, | |
| 1353 }; | |
| 1354 assert( argc==1 ); | |
| 1355 zIn = (u8*)sqlite3_value_text(argv[0]); | |
| 1356 if( zIn==0 ) zIn = (u8*)""; | |
| 1357 for(i=0; zIn[i] && !sqlite3Isalpha(zIn[i]); i++){} | |
| 1358 if( zIn[i] ){ | |
| 1359 u8 prevcode = iCode[zIn[i]&0x7f]; | |
| 1360 zResult[0] = sqlite3Toupper(zIn[i]); | |
| 1361 for(j=1; j<4 && zIn[i]; i++){ | |
| 1362 int code = iCode[zIn[i]&0x7f]; | |
| 1363 if( code>0 ){ | |
| 1364 if( code!=prevcode ){ | |
| 1365 prevcode = code; | |
| 1366 zResult[j++] = code + '0'; | |
| 1367 } | |
| 1368 }else{ | |
| 1369 prevcode = 0; | |
| 1370 } | |
| 1371 } | |
| 1372 while( j<4 ){ | |
| 1373 zResult[j++] = '0'; | |
| 1374 } | |
| 1375 zResult[j] = 0; | |
| 1376 sqlite3_result_text(context, zResult, 4, SQLITE_TRANSIENT); | |
| 1377 }else{ | |
| 1378 /* IMP: R-64894-50321 The string "?000" is returned if the argument | |
| 1379 ** is NULL or contains no ASCII alphabetic characters. */ | |
| 1380 sqlite3_result_text(context, "?000", 4, SQLITE_STATIC); | |
| 1381 } | |
| 1382 } | |
| 1383 #endif /* SQLITE_SOUNDEX */ | |
| 1384 | |
| 1385 #ifndef SQLITE_OMIT_LOAD_EXTENSION | |
| 1386 /* | |
| 1387 ** A function that loads a shared-library extension then returns NULL. | |
| 1388 */ | |
| 1389 static void loadExt(sqlite3_context *context, int argc, sqlite3_value **argv){ | |
| 1390 const char *zFile = (const char *)sqlite3_value_text(argv[0]); | |
| 1391 const char *zProc; | |
| 1392 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 1393 char *zErrMsg = 0; | |
| 1394 | |
| 1395 if( argc==2 ){ | |
| 1396 zProc = (const char *)sqlite3_value_text(argv[1]); | |
| 1397 }else{ | |
| 1398 zProc = 0; | |
| 1399 } | |
| 1400 if( zFile && sqlite3_load_extension(db, zFile, zProc, &zErrMsg) ){ | |
| 1401 sqlite3_result_error(context, zErrMsg, -1); | |
| 1402 sqlite3_free(zErrMsg); | |
| 1403 } | |
| 1404 } | |
| 1405 #endif | |
| 1406 | |
| 1407 | |
| 1408 /* | |
| 1409 ** An instance of the following structure holds the context of a | |
| 1410 ** sum() or avg() aggregate computation. | |
| 1411 */ | |
| 1412 typedef struct SumCtx SumCtx; | |
| 1413 struct SumCtx { | |
| 1414 double rSum; /* Floating point sum */ | |
| 1415 i64 iSum; /* Integer sum */ | |
| 1416 i64 cnt; /* Number of elements summed */ | |
| 1417 u8 overflow; /* True if integer overflow seen */ | |
| 1418 u8 approx; /* True if non-integer value was input to the sum */ | |
| 1419 }; | |
| 1420 | |
| 1421 /* | |
| 1422 ** Routines used to compute the sum, average, and total. | |
| 1423 ** | |
| 1424 ** The SUM() function follows the (broken) SQL standard which means | |
| 1425 ** that it returns NULL if it sums over no inputs. TOTAL returns | |
| 1426 ** 0.0 in that case. In addition, TOTAL always returns a float where | |
| 1427 ** SUM might return an integer if it never encounters a floating point | |
| 1428 ** value. TOTAL never fails, but SUM might through an exception if | |
| 1429 ** it overflows an integer. | |
| 1430 */ | |
| 1431 static void sumStep(sqlite3_context *context, int argc, sqlite3_value **argv){ | |
| 1432 SumCtx *p; | |
| 1433 int type; | |
| 1434 assert( argc==1 ); | |
| 1435 UNUSED_PARAMETER(argc); | |
| 1436 p = sqlite3_aggregate_context(context, sizeof(*p)); | |
| 1437 type = sqlite3_value_numeric_type(argv[0]); | |
| 1438 if( p && type!=SQLITE_NULL ){ | |
| 1439 p->cnt++; | |
| 1440 if( type==SQLITE_INTEGER ){ | |
| 1441 i64 v = sqlite3_value_int64(argv[0]); | |
| 1442 p->rSum += v; | |
| 1443 if( (p->approx|p->overflow)==0 && sqlite3AddInt64(&p->iSum, v) ){ | |
| 1444 p->overflow = 1; | |
| 1445 } | |
| 1446 }else{ | |
| 1447 p->rSum += sqlite3_value_double(argv[0]); | |
| 1448 p->approx = 1; | |
| 1449 } | |
| 1450 } | |
| 1451 } | |
| 1452 static void sumFinalize(sqlite3_context *context){ | |
| 1453 SumCtx *p; | |
| 1454 p = sqlite3_aggregate_context(context, 0); | |
| 1455 if( p && p->cnt>0 ){ | |
| 1456 if( p->overflow ){ | |
| 1457 sqlite3_result_error(context,"integer overflow",-1); | |
| 1458 }else if( p->approx ){ | |
| 1459 sqlite3_result_double(context, p->rSum); | |
| 1460 }else{ | |
| 1461 sqlite3_result_int64(context, p->iSum); | |
| 1462 } | |
| 1463 } | |
| 1464 } | |
| 1465 static void avgFinalize(sqlite3_context *context){ | |
| 1466 SumCtx *p; | |
| 1467 p = sqlite3_aggregate_context(context, 0); | |
| 1468 if( p && p->cnt>0 ){ | |
| 1469 sqlite3_result_double(context, p->rSum/(double)p->cnt); | |
| 1470 } | |
| 1471 } | |
| 1472 static void totalFinalize(sqlite3_context *context){ | |
| 1473 SumCtx *p; | |
| 1474 p = sqlite3_aggregate_context(context, 0); | |
| 1475 /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */ | |
| 1476 sqlite3_result_double(context, p ? p->rSum : (double)0); | |
| 1477 } | |
| 1478 | |
| 1479 /* | |
| 1480 ** The following structure keeps track of state information for the | |
| 1481 ** count() aggregate function. | |
| 1482 */ | |
| 1483 typedef struct CountCtx CountCtx; | |
| 1484 struct CountCtx { | |
| 1485 i64 n; | |
| 1486 }; | |
| 1487 | |
| 1488 /* | |
| 1489 ** Routines to implement the count() aggregate function. | |
| 1490 */ | |
| 1491 static void countStep(sqlite3_context *context, int argc, sqlite3_value **argv){ | |
| 1492 CountCtx *p; | |
| 1493 p = sqlite3_aggregate_context(context, sizeof(*p)); | |
| 1494 if( (argc==0 || SQLITE_NULL!=sqlite3_value_type(argv[0])) && p ){ | |
| 1495 p->n++; | |
| 1496 } | |
| 1497 | |
| 1498 #ifndef SQLITE_OMIT_DEPRECATED | |
| 1499 /* The sqlite3_aggregate_count() function is deprecated. But just to make | |
| 1500 ** sure it still operates correctly, verify that its count agrees with our | |
| 1501 ** internal count when using count(*) and when the total count can be | |
| 1502 ** expressed as a 32-bit integer. */ | |
| 1503 assert( argc==1 || p==0 || p->n>0x7fffffff | |
| 1504 || p->n==sqlite3_aggregate_count(context) ); | |
| 1505 #endif | |
| 1506 } | |
| 1507 static void countFinalize(sqlite3_context *context){ | |
| 1508 CountCtx *p; | |
| 1509 p = sqlite3_aggregate_context(context, 0); | |
| 1510 sqlite3_result_int64(context, p ? p->n : 0); | |
| 1511 } | |
| 1512 | |
| 1513 /* | |
| 1514 ** Routines to implement min() and max() aggregate functions. | |
| 1515 */ | |
| 1516 static void minmaxStep( | |
| 1517 sqlite3_context *context, | |
| 1518 int NotUsed, | |
| 1519 sqlite3_value **argv | |
| 1520 ){ | |
| 1521 Mem *pArg = (Mem *)argv[0]; | |
| 1522 Mem *pBest; | |
| 1523 UNUSED_PARAMETER(NotUsed); | |
| 1524 | |
| 1525 pBest = (Mem *)sqlite3_aggregate_context(context, sizeof(*pBest)); | |
| 1526 if( !pBest ) return; | |
| 1527 | |
| 1528 if( sqlite3_value_type(argv[0])==SQLITE_NULL ){ | |
| 1529 if( pBest->flags ) sqlite3SkipAccumulatorLoad(context); | |
| 1530 }else if( pBest->flags ){ | |
| 1531 int max; | |
| 1532 int cmp; | |
| 1533 CollSeq *pColl = sqlite3GetFuncCollSeq(context); | |
| 1534 /* This step function is used for both the min() and max() aggregates, | |
| 1535 ** the only difference between the two being that the sense of the | |
| 1536 ** comparison is inverted. For the max() aggregate, the | |
| 1537 ** sqlite3_user_data() function returns (void *)-1. For min() it | |
| 1538 ** returns (void *)db, where db is the sqlite3* database pointer. | |
| 1539 ** Therefore the next statement sets variable 'max' to 1 for the max() | |
| 1540 ** aggregate, or 0 for min(). | |
| 1541 */ | |
| 1542 max = sqlite3_user_data(context)!=0; | |
| 1543 cmp = sqlite3MemCompare(pBest, pArg, pColl); | |
| 1544 if( (max && cmp<0) || (!max && cmp>0) ){ | |
| 1545 sqlite3VdbeMemCopy(pBest, pArg); | |
| 1546 }else{ | |
| 1547 sqlite3SkipAccumulatorLoad(context); | |
| 1548 } | |
| 1549 }else{ | |
| 1550 pBest->db = sqlite3_context_db_handle(context); | |
| 1551 sqlite3VdbeMemCopy(pBest, pArg); | |
| 1552 } | |
| 1553 } | |
| 1554 static void minMaxFinalize(sqlite3_context *context){ | |
| 1555 sqlite3_value *pRes; | |
| 1556 pRes = (sqlite3_value *)sqlite3_aggregate_context(context, 0); | |
| 1557 if( pRes ){ | |
| 1558 if( pRes->flags ){ | |
| 1559 sqlite3_result_value(context, pRes); | |
| 1560 } | |
| 1561 sqlite3VdbeMemRelease(pRes); | |
| 1562 } | |
| 1563 } | |
| 1564 | |
| 1565 /* | |
| 1566 ** group_concat(EXPR, ?SEPARATOR?) | |
| 1567 */ | |
| 1568 static void groupConcatStep( | |
| 1569 sqlite3_context *context, | |
| 1570 int argc, | |
| 1571 sqlite3_value **argv | |
| 1572 ){ | |
| 1573 const char *zVal; | |
| 1574 StrAccum *pAccum; | |
| 1575 const char *zSep; | |
| 1576 int nVal, nSep; | |
| 1577 assert( argc==1 || argc==2 ); | |
| 1578 if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return; | |
| 1579 pAccum = (StrAccum*)sqlite3_aggregate_context(context, sizeof(*pAccum)); | |
| 1580 | |
| 1581 if( pAccum ){ | |
| 1582 sqlite3 *db = sqlite3_context_db_handle(context); | |
| 1583 int firstTerm = pAccum->mxAlloc==0; | |
| 1584 pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH]; | |
| 1585 if( !firstTerm ){ | |
| 1586 if( argc==2 ){ | |
| 1587 zSep = (char*)sqlite3_value_text(argv[1]); | |
| 1588 nSep = sqlite3_value_bytes(argv[1]); | |
| 1589 }else{ | |
| 1590 zSep = ","; | |
| 1591 nSep = 1; | |
| 1592 } | |
| 1593 if( nSep ) sqlite3StrAccumAppend(pAccum, zSep, nSep); | |
| 1594 } | |
| 1595 zVal = (char*)sqlite3_value_text(argv[0]); | |
| 1596 nVal = sqlite3_value_bytes(argv[0]); | |
| 1597 if( zVal ) sqlite3StrAccumAppend(pAccum, zVal, nVal); | |
| 1598 } | |
| 1599 } | |
| 1600 static void groupConcatFinalize(sqlite3_context *context){ | |
| 1601 StrAccum *pAccum; | |
| 1602 pAccum = sqlite3_aggregate_context(context, 0); | |
| 1603 if( pAccum ){ | |
| 1604 if( pAccum->accError==STRACCUM_TOOBIG ){ | |
| 1605 sqlite3_result_error_toobig(context); | |
| 1606 }else if( pAccum->accError==STRACCUM_NOMEM ){ | |
| 1607 sqlite3_result_error_nomem(context); | |
| 1608 }else{ | |
| 1609 sqlite3_result_text(context, sqlite3StrAccumFinish(pAccum), -1, | |
| 1610 sqlite3_free); | |
| 1611 } | |
| 1612 } | |
| 1613 } | |
| 1614 | |
| 1615 /* | |
| 1616 ** This routine does per-connection function registration. Most | |
| 1617 ** of the built-in functions above are part of the global function set. | |
| 1618 ** This routine only deals with those that are not global. | |
| 1619 */ | |
| 1620 void sqlite3RegisterBuiltinFunctions(sqlite3 *db){ | |
| 1621 int rc = sqlite3_overload_function(db, "MATCH", 2); | |
| 1622 assert( rc==SQLITE_NOMEM || rc==SQLITE_OK ); | |
| 1623 if( rc==SQLITE_NOMEM ){ | |
| 1624 db->mallocFailed = 1; | |
| 1625 } | |
| 1626 } | |
| 1627 | |
| 1628 /* | |
| 1629 ** Set the LIKEOPT flag on the 2-argument function with the given name. | |
| 1630 */ | |
| 1631 static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){ | |
| 1632 FuncDef *pDef; | |
| 1633 pDef = sqlite3FindFunction(db, zName, sqlite3Strlen30(zName), | |
| 1634 2, SQLITE_UTF8, 0); | |
| 1635 if( ALWAYS(pDef) ){ | |
| 1636 pDef->funcFlags |= flagVal; | |
| 1637 } | |
| 1638 } | |
| 1639 | |
| 1640 /* | |
| 1641 ** Register the built-in LIKE and GLOB functions. The caseSensitive | |
| 1642 ** parameter determines whether or not the LIKE operator is case | |
| 1643 ** sensitive. GLOB is always case sensitive. | |
| 1644 */ | |
| 1645 void sqlite3RegisterLikeFunctions(sqlite3 *db, int caseSensitive){ | |
| 1646 struct compareInfo *pInfo; | |
| 1647 if( caseSensitive ){ | |
| 1648 pInfo = (struct compareInfo*)&likeInfoAlt; | |
| 1649 }else{ | |
| 1650 pInfo = (struct compareInfo*)&likeInfoNorm; | |
| 1651 } | |
| 1652 sqlite3CreateFunc(db, "like", 2, SQLITE_UTF8, pInfo, likeFunc, 0, 0, 0); | |
| 1653 sqlite3CreateFunc(db, "like", 3, SQLITE_UTF8, pInfo, likeFunc, 0, 0, 0); | |
| 1654 sqlite3CreateFunc(db, "glob", 2, SQLITE_UTF8, | |
| 1655 (struct compareInfo*)&globInfo, likeFunc, 0, 0, 0); | |
| 1656 setLikeOptFlag(db, "glob", SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE); | |
| 1657 setLikeOptFlag(db, "like", | |
| 1658 caseSensitive ? (SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE) : SQLITE_FUNC_LIKE); | |
| 1659 } | |
| 1660 | |
| 1661 /* | |
| 1662 ** pExpr points to an expression which implements a function. If | |
| 1663 ** it is appropriate to apply the LIKE optimization to that function | |
| 1664 ** then set aWc[0] through aWc[2] to the wildcard characters and | |
| 1665 ** return TRUE. If the function is not a LIKE-style function then | |
| 1666 ** return FALSE. | |
| 1667 ** | |
| 1668 ** *pIsNocase is set to true if uppercase and lowercase are equivalent for | |
| 1669 ** the function (default for LIKE). If the function makes the distinction | |
| 1670 ** between uppercase and lowercase (as does GLOB) then *pIsNocase is set to | |
| 1671 ** false. | |
| 1672 */ | |
| 1673 int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){ | |
| 1674 FuncDef *pDef; | |
| 1675 if( pExpr->op!=TK_FUNCTION | |
| 1676 || !pExpr->x.pList | |
| 1677 || pExpr->x.pList->nExpr!=2 | |
| 1678 ){ | |
| 1679 return 0; | |
| 1680 } | |
| 1681 assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); | |
| 1682 pDef = sqlite3FindFunction(db, pExpr->u.zToken, | |
| 1683 sqlite3Strlen30(pExpr->u.zToken), | |
| 1684 2, SQLITE_UTF8, 0); | |
| 1685 if( NEVER(pDef==0) || (pDef->funcFlags & SQLITE_FUNC_LIKE)==0 ){ | |
| 1686 return 0; | |
| 1687 } | |
| 1688 | |
| 1689 /* The memcpy() statement assumes that the wildcard characters are | |
| 1690 ** the first three statements in the compareInfo structure. The | |
| 1691 ** asserts() that follow verify that assumption | |
| 1692 */ | |
| 1693 memcpy(aWc, pDef->pUserData, 3); | |
| 1694 assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll ); | |
| 1695 assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne ); | |
| 1696 assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet ); | |
| 1697 *pIsNocase = (pDef->funcFlags & SQLITE_FUNC_CASE)==0; | |
| 1698 return 1; | |
| 1699 } | |
| 1700 | |
| 1701 /* | |
| 1702 ** All of the FuncDef structures in the aBuiltinFunc[] array above | |
| 1703 ** to the global function hash table. This occurs at start-time (as | |
| 1704 ** a consequence of calling sqlite3_initialize()). | |
| 1705 ** | |
| 1706 ** After this routine runs | |
| 1707 */ | |
| 1708 void sqlite3RegisterGlobalFunctions(void){ | |
| 1709 /* | |
| 1710 ** The following array holds FuncDef structures for all of the functions | |
| 1711 ** defined in this file. | |
| 1712 ** | |
| 1713 ** The array cannot be constant since changes are made to the | |
| 1714 ** FuncDef.pHash elements at start-time. The elements of this array | |
| 1715 ** are read-only after initialization is complete. | |
| 1716 */ | |
| 1717 static SQLITE_WSD FuncDef aBuiltinFunc[] = { | |
| 1718 FUNCTION(ltrim, 1, 1, 0, trimFunc ), | |
| 1719 FUNCTION(ltrim, 2, 1, 0, trimFunc ), | |
| 1720 FUNCTION(rtrim, 1, 2, 0, trimFunc ), | |
| 1721 FUNCTION(rtrim, 2, 2, 0, trimFunc ), | |
| 1722 FUNCTION(trim, 1, 3, 0, trimFunc ), | |
| 1723 FUNCTION(trim, 2, 3, 0, trimFunc ), | |
| 1724 FUNCTION(min, -1, 0, 1, minmaxFunc ), | |
| 1725 FUNCTION(min, 0, 0, 1, 0 ), | |
| 1726 AGGREGATE2(min, 1, 0, 1, minmaxStep, minMaxFinalize, | |
| 1727 SQLITE_FUNC_MINMAX ), | |
| 1728 FUNCTION(max, -1, 1, 1, minmaxFunc ), | |
| 1729 FUNCTION(max, 0, 1, 1, 0 ), | |
| 1730 AGGREGATE2(max, 1, 1, 1, minmaxStep, minMaxFinalize, | |
| 1731 SQLITE_FUNC_MINMAX ), | |
| 1732 FUNCTION2(typeof, 1, 0, 0, typeofFunc, SQLITE_FUNC_TYPEOF), | |
| 1733 FUNCTION2(length, 1, 0, 0, lengthFunc, SQLITE_FUNC_LENGTH), | |
| 1734 FUNCTION(instr, 2, 0, 0, instrFunc ), | |
| 1735 FUNCTION(substr, 2, 0, 0, substrFunc ), | |
| 1736 FUNCTION(substr, 3, 0, 0, substrFunc ), | |
| 1737 FUNCTION(printf, -1, 0, 0, printfFunc ), | |
| 1738 FUNCTION(unicode, 1, 0, 0, unicodeFunc ), | |
| 1739 FUNCTION(char, -1, 0, 0, charFunc ), | |
| 1740 FUNCTION(abs, 1, 0, 0, absFunc ), | |
| 1741 #ifndef SQLITE_OMIT_FLOATING_POINT | |
| 1742 FUNCTION(round, 1, 0, 0, roundFunc ), | |
| 1743 FUNCTION(round, 2, 0, 0, roundFunc ), | |
| 1744 #endif | |
| 1745 FUNCTION(upper, 1, 0, 0, upperFunc ), | |
| 1746 FUNCTION(lower, 1, 0, 0, lowerFunc ), | |
| 1747 FUNCTION(coalesce, 1, 0, 0, 0 ), | |
| 1748 FUNCTION(coalesce, 0, 0, 0, 0 ), | |
| 1749 FUNCTION2(coalesce, -1, 0, 0, noopFunc, SQLITE_FUNC_COALESCE), | |
| 1750 FUNCTION(hex, 1, 0, 0, hexFunc ), | |
| 1751 FUNCTION2(ifnull, 2, 0, 0, noopFunc, SQLITE_FUNC_COALESCE), | |
| 1752 FUNCTION2(unlikely, 1, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), | |
| 1753 FUNCTION2(likelihood, 2, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), | |
| 1754 FUNCTION2(likely, 1, 0, 0, noopFunc, SQLITE_FUNC_UNLIKELY), | |
| 1755 VFUNCTION(random, 0, 0, 0, randomFunc ), | |
| 1756 VFUNCTION(randomblob, 1, 0, 0, randomBlob ), | |
| 1757 FUNCTION(nullif, 2, 0, 1, nullifFunc ), | |
| 1758 DFUNCTION(sqlite_version, 0, 0, 0, versionFunc ), | |
| 1759 DFUNCTION(sqlite_source_id, 0, 0, 0, sourceidFunc ), | |
| 1760 FUNCTION(sqlite_log, 2, 0, 0, errlogFunc ), | |
| 1761 #if SQLITE_USER_AUTHENTICATION | |
| 1762 FUNCTION(sqlite_crypt, 2, 0, 0, sqlite3CryptFunc ), | |
| 1763 #endif | |
| 1764 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS | |
| 1765 DFUNCTION(sqlite_compileoption_used,1, 0, 0, compileoptionusedFunc ), | |
| 1766 DFUNCTION(sqlite_compileoption_get, 1, 0, 0, compileoptiongetFunc ), | |
| 1767 #endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */ | |
| 1768 FUNCTION(quote, 1, 0, 0, quoteFunc ), | |
| 1769 VFUNCTION(last_insert_rowid, 0, 0, 0, last_insert_rowid), | |
| 1770 VFUNCTION(changes, 0, 0, 0, changes ), | |
| 1771 VFUNCTION(total_changes, 0, 0, 0, total_changes ), | |
| 1772 FUNCTION(replace, 3, 0, 0, replaceFunc ), | |
| 1773 FUNCTION(zeroblob, 1, 0, 0, zeroblobFunc ), | |
| 1774 #ifdef SQLITE_SOUNDEX | |
| 1775 FUNCTION(soundex, 1, 0, 0, soundexFunc ), | |
| 1776 #endif | |
| 1777 #ifndef SQLITE_OMIT_LOAD_EXTENSION | |
| 1778 VFUNCTION(load_extension, 1, 0, 0, loadExt ), | |
| 1779 VFUNCTION(load_extension, 2, 0, 0, loadExt ), | |
| 1780 #endif | |
| 1781 AGGREGATE(sum, 1, 0, 0, sumStep, sumFinalize ), | |
| 1782 AGGREGATE(total, 1, 0, 0, sumStep, totalFinalize ), | |
| 1783 AGGREGATE(avg, 1, 0, 0, sumStep, avgFinalize ), | |
| 1784 AGGREGATE2(count, 0, 0, 0, countStep, countFinalize, | |
| 1785 SQLITE_FUNC_COUNT ), | |
| 1786 AGGREGATE(count, 1, 0, 0, countStep, countFinalize ), | |
| 1787 AGGREGATE(group_concat, 1, 0, 0, groupConcatStep, groupConcatFinalize), | |
| 1788 AGGREGATE(group_concat, 2, 0, 0, groupConcatStep, groupConcatFinalize), | |
| 1789 | |
| 1790 LIKEFUNC(glob, 2, &globInfo, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), | |
| 1791 #ifdef SQLITE_CASE_SENSITIVE_LIKE | |
| 1792 LIKEFUNC(like, 2, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), | |
| 1793 LIKEFUNC(like, 3, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE), | |
| 1794 #else | |
| 1795 LIKEFUNC(like, 2, &likeInfoNorm, SQLITE_FUNC_LIKE), | |
| 1796 LIKEFUNC(like, 3, &likeInfoNorm, SQLITE_FUNC_LIKE), | |
| 1797 #endif | |
| 1798 }; | |
| 1799 | |
| 1800 int i; | |
| 1801 FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions); | |
| 1802 FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aBuiltinFunc); | |
| 1803 | |
| 1804 for(i=0; i<ArraySize(aBuiltinFunc); i++){ | |
| 1805 sqlite3FuncDefInsert(pHash, &aFunc[i]); | |
| 1806 } | |
| 1807 sqlite3RegisterDateTimeFunctions(); | |
| 1808 #ifndef SQLITE_OMIT_ALTERTABLE | |
| 1809 sqlite3AlterFunctions(); | |
| 1810 #endif | |
| 1811 #if defined(SQLITE_ENABLE_STAT3) || defined(SQLITE_ENABLE_STAT4) | |
| 1812 sqlite3AnalyzeFunctions(); | |
| 1813 #endif | |
| 1814 } | |
| OLD | NEW |
|---|
Chromium Code Reviews
Issue 2846743003:
[sql] Remove SQLite 3.10.2 reference directory. (Closed)
