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| 1 /* | |
| 2 ** 2007 May 6 | |
| 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 ** $Id: icu.c,v 1.7 2007/12/13 21:54:11 drh Exp $ | |
| 13 ** | |
| 14 ** This file implements an integration between the ICU library | |
| 15 ** ("International Components for Unicode", an open-source library | |
| 16 ** for handling unicode data) and SQLite. The integration uses | |
| 17 ** ICU to provide the following to SQLite: | |
| 18 ** | |
| 19 ** * An implementation of the SQL regexp() function (and hence REGEXP | |
| 20 ** operator) using the ICU uregex_XX() APIs. | |
| 21 ** | |
| 22 ** * Implementations of the SQL scalar upper() and lower() functions | |
| 23 ** for case mapping. | |
| 24 ** | |
| 25 ** * Integration of ICU and SQLite collation sequences. | |
| 26 ** | |
| 27 ** * An implementation of the LIKE operator that uses ICU to | |
| 28 ** provide case-independent matching. | |
| 29 */ | |
| 30 | |
| 31 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_ICU) | |
| 32 | |
| 33 /* Include ICU headers */ | |
| 34 #include <unicode/utypes.h> | |
| 35 #include <unicode/uregex.h> | |
| 36 #include <unicode/ustring.h> | |
| 37 #include <unicode/ucol.h> | |
| 38 | |
| 39 #include <assert.h> | |
| 40 | |
| 41 #ifndef SQLITE_CORE | |
| 42 #include "sqlite3ext.h" | |
| 43 SQLITE_EXTENSION_INIT1 | |
| 44 #else | |
| 45 #include "sqlite3.h" | |
| 46 #endif | |
| 47 | |
| 48 /* | |
| 49 ** Maximum length (in bytes) of the pattern in a LIKE or GLOB | |
| 50 ** operator. | |
| 51 */ | |
| 52 #ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH | |
| 53 # define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000 | |
| 54 #endif | |
| 55 | |
| 56 /* | |
| 57 ** Version of sqlite3_free() that is always a function, never a macro. | |
| 58 */ | |
| 59 static void xFree(void *p){ | |
| 60 sqlite3_free(p); | |
| 61 } | |
| 62 | |
| 63 /* | |
| 64 ** Compare two UTF-8 strings for equality where the first string is | |
| 65 ** a "LIKE" expression. Return true (1) if they are the same and | |
| 66 ** false (0) if they are different. | |
| 67 */ | |
| 68 static int icuLikeCompare( | |
| 69 const uint8_t *zPattern, /* LIKE pattern */ | |
| 70 const uint8_t *zString, /* The UTF-8 string to compare against */ | |
| 71 const UChar32 uEsc /* The escape character */ | |
| 72 ){ | |
| 73 static const int MATCH_ONE = (UChar32)'_'; | |
| 74 static const int MATCH_ALL = (UChar32)'%'; | |
| 75 | |
| 76 int iPattern = 0; /* Current byte index in zPattern */ | |
| 77 int iString = 0; /* Current byte index in zString */ | |
| 78 | |
| 79 int prevEscape = 0; /* True if the previous character was uEsc */ | |
| 80 | |
| 81 while( zPattern[iPattern]!=0 ){ | |
| 82 | |
| 83 /* Read (and consume) the next character from the input pattern. */ | |
| 84 UChar32 uPattern; | |
| 85 U8_NEXT_UNSAFE(zPattern, iPattern, uPattern); | |
| 86 assert(uPattern!=0); | |
| 87 | |
| 88 /* There are now 4 possibilities: | |
| 89 ** | |
| 90 ** 1. uPattern is an unescaped match-all character "%", | |
| 91 ** 2. uPattern is an unescaped match-one character "_", | |
| 92 ** 3. uPattern is an unescaped escape character, or | |
| 93 ** 4. uPattern is to be handled as an ordinary character | |
| 94 */ | |
| 95 if( !prevEscape && uPattern==MATCH_ALL ){ | |
| 96 /* Case 1. */ | |
| 97 uint8_t c; | |
| 98 | |
| 99 /* Skip any MATCH_ALL or MATCH_ONE characters that follow a | |
| 100 ** MATCH_ALL. For each MATCH_ONE, skip one character in the | |
| 101 ** test string. | |
| 102 */ | |
| 103 while( (c=zPattern[iPattern]) == MATCH_ALL || c == MATCH_ONE ){ | |
| 104 if( c==MATCH_ONE ){ | |
| 105 if( zString[iString]==0 ) return 0; | |
| 106 U8_FWD_1_UNSAFE(zString, iString); | |
| 107 } | |
| 108 iPattern++; | |
| 109 } | |
| 110 | |
| 111 if( zPattern[iPattern]==0 ) return 1; | |
| 112 | |
| 113 while( zString[iString] ){ | |
| 114 if( icuLikeCompare(&zPattern[iPattern], &zString[iString], uEsc) ){ | |
| 115 return 1; | |
| 116 } | |
| 117 U8_FWD_1_UNSAFE(zString, iString); | |
| 118 } | |
| 119 return 0; | |
| 120 | |
| 121 }else if( !prevEscape && uPattern==MATCH_ONE ){ | |
| 122 /* Case 2. */ | |
| 123 if( zString[iString]==0 ) return 0; | |
| 124 U8_FWD_1_UNSAFE(zString, iString); | |
| 125 | |
| 126 }else if( !prevEscape && uPattern==uEsc){ | |
| 127 /* Case 3. */ | |
| 128 prevEscape = 1; | |
| 129 | |
| 130 }else{ | |
| 131 /* Case 4. */ | |
| 132 UChar32 uString; | |
| 133 U8_NEXT_UNSAFE(zString, iString, uString); | |
| 134 uString = u_foldCase(uString, U_FOLD_CASE_DEFAULT); | |
| 135 uPattern = u_foldCase(uPattern, U_FOLD_CASE_DEFAULT); | |
| 136 if( uString!=uPattern ){ | |
| 137 return 0; | |
| 138 } | |
| 139 prevEscape = 0; | |
| 140 } | |
| 141 } | |
| 142 | |
| 143 return zString[iString]==0; | |
| 144 } | |
| 145 | |
| 146 /* | |
| 147 ** Implementation of the like() SQL function. This function implements | |
| 148 ** the build-in LIKE operator. The first argument to the function is the | |
| 149 ** pattern and the second argument is the string. So, the SQL statements: | |
| 150 ** | |
| 151 ** A LIKE B | |
| 152 ** | |
| 153 ** is implemented as like(B, A). If there is an escape character E, | |
| 154 ** | |
| 155 ** A LIKE B ESCAPE E | |
| 156 ** | |
| 157 ** is mapped to like(B, A, E). | |
| 158 */ | |
| 159 static void icuLikeFunc( | |
| 160 sqlite3_context *context, | |
| 161 int argc, | |
| 162 sqlite3_value **argv | |
| 163 ){ | |
| 164 const unsigned char *zA = sqlite3_value_text(argv[0]); | |
| 165 const unsigned char *zB = sqlite3_value_text(argv[1]); | |
| 166 UChar32 uEsc = 0; | |
| 167 | |
| 168 /* Limit the length of the LIKE or GLOB pattern to avoid problems | |
| 169 ** of deep recursion and N*N behavior in patternCompare(). | |
| 170 */ | |
| 171 if( sqlite3_value_bytes(argv[0])>SQLITE_MAX_LIKE_PATTERN_LENGTH ){ | |
| 172 sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1); | |
| 173 return; | |
| 174 } | |
| 175 | |
| 176 | |
| 177 if( argc==3 ){ | |
| 178 /* The escape character string must consist of a single UTF-8 character. | |
| 179 ** Otherwise, return an error. | |
| 180 */ | |
| 181 int nE= sqlite3_value_bytes(argv[2]); | |
| 182 const unsigned char *zE = sqlite3_value_text(argv[2]); | |
| 183 int i = 0; | |
| 184 if( zE==0 ) return; | |
| 185 U8_NEXT(zE, i, nE, uEsc); | |
| 186 if( i!=nE){ | |
| 187 sqlite3_result_error(context, | |
| 188 "ESCAPE expression must be a single character", -1); | |
| 189 return; | |
| 190 } | |
| 191 } | |
| 192 | |
| 193 if( zA && zB ){ | |
| 194 sqlite3_result_int(context, icuLikeCompare(zA, zB, uEsc)); | |
| 195 } | |
| 196 } | |
| 197 | |
| 198 /* | |
| 199 ** This function is called when an ICU function called from within | |
| 200 ** the implementation of an SQL scalar function returns an error. | |
| 201 ** | |
| 202 ** The scalar function context passed as the first argument is | |
| 203 ** loaded with an error message based on the following two args. | |
| 204 */ | |
| 205 static void icuFunctionError( | |
| 206 sqlite3_context *pCtx, /* SQLite scalar function context */ | |
| 207 const char *zName, /* Name of ICU function that failed */ | |
| 208 UErrorCode e /* Error code returned by ICU function */ | |
| 209 ){ | |
| 210 char zBuf[128]; | |
| 211 sqlite3_snprintf(128, zBuf, "ICU error: %s(): %s", zName, u_errorName(e)); | |
| 212 zBuf[127] = '\0'; | |
| 213 sqlite3_result_error(pCtx, zBuf, -1); | |
| 214 } | |
| 215 | |
| 216 /* | |
| 217 ** Function to delete compiled regexp objects. Registered as | |
| 218 ** a destructor function with sqlite3_set_auxdata(). | |
| 219 */ | |
| 220 static void icuRegexpDelete(void *p){ | |
| 221 URegularExpression *pExpr = (URegularExpression *)p; | |
| 222 uregex_close(pExpr); | |
| 223 } | |
| 224 | |
| 225 /* | |
| 226 ** Implementation of SQLite REGEXP operator. This scalar function takes | |
| 227 ** two arguments. The first is a regular expression pattern to compile | |
| 228 ** the second is a string to match against that pattern. If either | |
| 229 ** argument is an SQL NULL, then NULL Is returned. Otherwise, the result | |
| 230 ** is 1 if the string matches the pattern, or 0 otherwise. | |
| 231 ** | |
| 232 ** SQLite maps the regexp() function to the regexp() operator such | |
| 233 ** that the following two are equivalent: | |
| 234 ** | |
| 235 ** zString REGEXP zPattern | |
| 236 ** regexp(zPattern, zString) | |
| 237 ** | |
| 238 ** Uses the following ICU regexp APIs: | |
| 239 ** | |
| 240 ** uregex_open() | |
| 241 ** uregex_matches() | |
| 242 ** uregex_close() | |
| 243 */ | |
| 244 static void icuRegexpFunc(sqlite3_context *p, int nArg, sqlite3_value **apArg){ | |
| 245 UErrorCode status = U_ZERO_ERROR; | |
| 246 URegularExpression *pExpr; | |
| 247 UBool res; | |
| 248 const UChar *zString = sqlite3_value_text16(apArg[1]); | |
| 249 | |
| 250 (void)nArg; /* Unused parameter */ | |
| 251 | |
| 252 /* If the left hand side of the regexp operator is NULL, | |
| 253 ** then the result is also NULL. | |
| 254 */ | |
| 255 if( !zString ){ | |
| 256 return; | |
| 257 } | |
| 258 | |
| 259 pExpr = sqlite3_get_auxdata(p, 0); | |
| 260 if( !pExpr ){ | |
| 261 const UChar *zPattern = sqlite3_value_text16(apArg[0]); | |
| 262 if( !zPattern ){ | |
| 263 return; | |
| 264 } | |
| 265 pExpr = uregex_open(zPattern, -1, 0, 0, &status); | |
| 266 | |
| 267 if( U_SUCCESS(status) ){ | |
| 268 sqlite3_set_auxdata(p, 0, pExpr, icuRegexpDelete); | |
| 269 }else{ | |
| 270 assert(!pExpr); | |
| 271 icuFunctionError(p, "uregex_open", status); | |
| 272 return; | |
| 273 } | |
| 274 } | |
| 275 | |
| 276 /* Configure the text that the regular expression operates on. */ | |
| 277 uregex_setText(pExpr, zString, -1, &status); | |
| 278 if( !U_SUCCESS(status) ){ | |
| 279 icuFunctionError(p, "uregex_setText", status); | |
| 280 return; | |
| 281 } | |
| 282 | |
| 283 /* Attempt the match */ | |
| 284 res = uregex_matches(pExpr, 0, &status); | |
| 285 if( !U_SUCCESS(status) ){ | |
| 286 icuFunctionError(p, "uregex_matches", status); | |
| 287 return; | |
| 288 } | |
| 289 | |
| 290 /* Set the text that the regular expression operates on to a NULL | |
| 291 ** pointer. This is not really necessary, but it is tidier than | |
| 292 ** leaving the regular expression object configured with an invalid | |
| 293 ** pointer after this function returns. | |
| 294 */ | |
| 295 uregex_setText(pExpr, 0, 0, &status); | |
| 296 | |
| 297 /* Return 1 or 0. */ | |
| 298 sqlite3_result_int(p, res ? 1 : 0); | |
| 299 } | |
| 300 | |
| 301 /* | |
| 302 ** Implementations of scalar functions for case mapping - upper() and | |
| 303 ** lower(). Function upper() converts its input to upper-case (ABC). | |
| 304 ** Function lower() converts to lower-case (abc). | |
| 305 ** | |
| 306 ** ICU provides two types of case mapping, "general" case mapping and | |
| 307 ** "language specific". Refer to ICU documentation for the differences | |
| 308 ** between the two. | |
| 309 ** | |
| 310 ** To utilise "general" case mapping, the upper() or lower() scalar | |
| 311 ** functions are invoked with one argument: | |
| 312 ** | |
| 313 ** upper('ABC') -> 'abc' | |
| 314 ** lower('abc') -> 'ABC' | |
| 315 ** | |
| 316 ** To access ICU "language specific" case mapping, upper() or lower() | |
| 317 ** should be invoked with two arguments. The second argument is the name | |
| 318 ** of the locale to use. Passing an empty string ("") or SQL NULL value | |
| 319 ** as the second argument is the same as invoking the 1 argument version | |
| 320 ** of upper() or lower(). | |
| 321 ** | |
| 322 ** lower('I', 'en_us') -> 'i' | |
| 323 ** lower('I', 'tr_tr') -> 'ı' (small dotless i) | |
| 324 ** | |
| 325 ** http://www.icu-project.org/userguide/posix.html#case_mappings | |
| 326 */ | |
| 327 static void icuCaseFunc16(sqlite3_context *p, int nArg, sqlite3_value **apArg){ | |
| 328 const UChar *zInput; | |
| 329 UChar *zOutput; | |
| 330 int nInput; | |
| 331 int nOutput; | |
| 332 | |
| 333 UErrorCode status = U_ZERO_ERROR; | |
| 334 const char *zLocale = 0; | |
| 335 | |
| 336 assert(nArg==1 || nArg==2); | |
| 337 if( nArg==2 ){ | |
| 338 zLocale = (const char *)sqlite3_value_text(apArg[1]); | |
| 339 } | |
| 340 | |
| 341 zInput = sqlite3_value_text16(apArg[0]); | |
| 342 if( !zInput ){ | |
| 343 return; | |
| 344 } | |
| 345 nInput = sqlite3_value_bytes16(apArg[0]); | |
| 346 | |
| 347 nOutput = nInput * 2 + 2; | |
| 348 zOutput = sqlite3_malloc(nOutput); | |
| 349 if( !zOutput ){ | |
| 350 return; | |
| 351 } | |
| 352 | |
| 353 if( sqlite3_user_data(p) ){ | |
| 354 u_strToUpper(zOutput, nOutput/2, zInput, nInput/2, zLocale, &status); | |
| 355 }else{ | |
| 356 u_strToLower(zOutput, nOutput/2, zInput, nInput/2, zLocale, &status); | |
| 357 } | |
| 358 | |
| 359 if( !U_SUCCESS(status) ){ | |
| 360 icuFunctionError(p, "u_strToLower()/u_strToUpper", status); | |
| 361 return; | |
| 362 } | |
| 363 | |
| 364 sqlite3_result_text16(p, zOutput, -1, xFree); | |
| 365 } | |
| 366 | |
| 367 /* | |
| 368 ** Collation sequence destructor function. The pCtx argument points to | |
| 369 ** a UCollator structure previously allocated using ucol_open(). | |
| 370 */ | |
| 371 static void icuCollationDel(void *pCtx){ | |
| 372 UCollator *p = (UCollator *)pCtx; | |
| 373 ucol_close(p); | |
| 374 } | |
| 375 | |
| 376 /* | |
| 377 ** Collation sequence comparison function. The pCtx argument points to | |
| 378 ** a UCollator structure previously allocated using ucol_open(). | |
| 379 */ | |
| 380 static int icuCollationColl( | |
| 381 void *pCtx, | |
| 382 int nLeft, | |
| 383 const void *zLeft, | |
| 384 int nRight, | |
| 385 const void *zRight | |
| 386 ){ | |
| 387 UCollationResult res; | |
| 388 UCollator *p = (UCollator *)pCtx; | |
| 389 res = ucol_strcoll(p, (UChar *)zLeft, nLeft/2, (UChar *)zRight, nRight/2); | |
| 390 switch( res ){ | |
| 391 case UCOL_LESS: return -1; | |
| 392 case UCOL_GREATER: return +1; | |
| 393 case UCOL_EQUAL: return 0; | |
| 394 } | |
| 395 assert(!"Unexpected return value from ucol_strcoll()"); | |
| 396 return 0; | |
| 397 } | |
| 398 | |
| 399 /* | |
| 400 ** Implementation of the scalar function icu_load_collation(). | |
| 401 ** | |
| 402 ** This scalar function is used to add ICU collation based collation | |
| 403 ** types to an SQLite database connection. It is intended to be called | |
| 404 ** as follows: | |
| 405 ** | |
| 406 ** SELECT icu_load_collation(<locale>, <collation-name>); | |
| 407 ** | |
| 408 ** Where <locale> is a string containing an ICU locale identifier (i.e. | |
| 409 ** "en_AU", "tr_TR" etc.) and <collation-name> is the name of the | |
| 410 ** collation sequence to create. | |
| 411 */ | |
| 412 static void icuLoadCollation( | |
| 413 sqlite3_context *p, | |
| 414 int nArg, | |
| 415 sqlite3_value **apArg | |
| 416 ){ | |
| 417 sqlite3 *db = (sqlite3 *)sqlite3_user_data(p); | |
| 418 UErrorCode status = U_ZERO_ERROR; | |
| 419 const char *zLocale; /* Locale identifier - (eg. "jp_JP") */ | |
| 420 const char *zName; /* SQL Collation sequence name (eg. "japanese") */ | |
| 421 UCollator *pUCollator; /* ICU library collation object */ | |
| 422 int rc; /* Return code from sqlite3_create_collation_x() */ | |
| 423 | |
| 424 assert(nArg==2); | |
| 425 zLocale = (const char *)sqlite3_value_text(apArg[0]); | |
| 426 zName = (const char *)sqlite3_value_text(apArg[1]); | |
| 427 | |
| 428 if( !zLocale || !zName ){ | |
| 429 return; | |
| 430 } | |
| 431 | |
| 432 pUCollator = ucol_open(zLocale, &status); | |
| 433 if( !U_SUCCESS(status) ){ | |
| 434 icuFunctionError(p, "ucol_open", status); | |
| 435 return; | |
| 436 } | |
| 437 assert(p); | |
| 438 | |
| 439 rc = sqlite3_create_collation_v2(db, zName, SQLITE_UTF16, (void *)pUCollator, | |
| 440 icuCollationColl, icuCollationDel | |
| 441 ); | |
| 442 if( rc!=SQLITE_OK ){ | |
| 443 ucol_close(pUCollator); | |
| 444 sqlite3_result_error(p, "Error registering collation function", -1); | |
| 445 } | |
| 446 } | |
| 447 | |
| 448 /* | |
| 449 ** Register the ICU extension functions with database db. | |
| 450 */ | |
| 451 int sqlite3IcuInit(sqlite3 *db){ | |
| 452 struct IcuScalar { | |
| 453 const char *zName; /* Function name */ | |
| 454 int nArg; /* Number of arguments */ | |
| 455 int enc; /* Optimal text encoding */ | |
| 456 void *pContext; /* sqlite3_user_data() context */ | |
| 457 void (*xFunc)(sqlite3_context*,int,sqlite3_value**); | |
| 458 } scalars[] = { | |
| 459 {"regexp", 2, SQLITE_ANY, 0, icuRegexpFunc}, | |
| 460 | |
| 461 {"lower", 1, SQLITE_UTF16, 0, icuCaseFunc16}, | |
| 462 {"lower", 2, SQLITE_UTF16, 0, icuCaseFunc16}, | |
| 463 {"upper", 1, SQLITE_UTF16, (void*)1, icuCaseFunc16}, | |
| 464 {"upper", 2, SQLITE_UTF16, (void*)1, icuCaseFunc16}, | |
| 465 | |
| 466 {"lower", 1, SQLITE_UTF8, 0, icuCaseFunc16}, | |
| 467 {"lower", 2, SQLITE_UTF8, 0, icuCaseFunc16}, | |
| 468 {"upper", 1, SQLITE_UTF8, (void*)1, icuCaseFunc16}, | |
| 469 {"upper", 2, SQLITE_UTF8, (void*)1, icuCaseFunc16}, | |
| 470 | |
| 471 {"like", 2, SQLITE_UTF8, 0, icuLikeFunc}, | |
| 472 {"like", 3, SQLITE_UTF8, 0, icuLikeFunc}, | |
| 473 | |
| 474 {"icu_load_collation", 2, SQLITE_UTF8, (void*)db, icuLoadCollation}, | |
| 475 }; | |
| 476 | |
| 477 int rc = SQLITE_OK; | |
| 478 int i; | |
| 479 | |
| 480 for(i=0; rc==SQLITE_OK && i<(int)(sizeof(scalars)/sizeof(scalars[0])); i++){ | |
| 481 struct IcuScalar *p = &scalars[i]; | |
| 482 rc = sqlite3_create_function( | |
| 483 db, p->zName, p->nArg, p->enc, p->pContext, p->xFunc, 0, 0 | |
| 484 ); | |
| 485 } | |
| 486 | |
| 487 return rc; | |
| 488 } | |
| 489 | |
| 490 #if !SQLITE_CORE | |
| 491 #ifdef _WIN32 | |
| 492 __declspec(dllexport) | |
| 493 #endif | |
| 494 int sqlite3_icu_init( | |
| 495 sqlite3 *db, | |
| 496 char **pzErrMsg, | |
| 497 const sqlite3_api_routines *pApi | |
| 498 ){ | |
| 499 SQLITE_EXTENSION_INIT2(pApi) | |
| 500 return sqlite3IcuInit(db); | |
| 501 } | |
| 502 #endif | |
| 503 | |
| 504 #endif | |
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Chromium Code Reviews
Issue 2363173002:
[sqlite] Remove obsolete reference version 3.8.7.4. (Closed)
