1 /* 2 ** 2004 April 13 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 routines used to translate between UTF-8, 13 ** UTF-16, UTF-16BE, and UTF-16LE. 14 ** 15 ** $Id: utf.c,v 1.63 2008/07/29 11:25:14 danielk1977 Exp $ 16 ** 17 ** Notes on UTF-8: 18 ** 19 ** Byte-0 Byte-1 Byte-2 Byte-3 Value 20 ** 0xxxxxxx 00000000 00000000 0xxxxxxx 21 ** 110yyyyy 10xxxxxx 00000000 00000yyy yyxxxxxx 22 ** 1110zzzz 10yyyyyy 10xxxxxx 00000000 zzzzyyyy yyxxxxxx 23 ** 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx 000uuuuu zzzzyyyy yyxxxxxx 24 ** 25 ** 26 ** Notes on UTF-16: (with wwww+1==uuuuu) 27 ** 28 ** Word-0 Word-1 Value 29 ** 110110ww wwzzzzyy 110111yy yyxxxxxx 000uuuuu zzzzyyyy yyxxxxxx 30 ** zzzzyyyy yyxxxxxx 00000000 zzzzyyyy yyxxxxxx 31 ** 32 ** 33 ** BOM or Byte Order Mark: 34 ** 0xff 0xfe little-endian utf-16 follows 35 ** 0xfe 0xff big-endian utf-16 follows 36 ** 37 */ 38 #include "sqliteInt.h" 39 #include <assert.h> 40 #include "vdbeInt.h" 41 42 /* 43 ** The following constant value is used by the SQLITE_BIGENDIAN and 44 ** SQLITE_LITTLEENDIAN macros. 45 */ 46 const int sqlite3one = 1; 47 48 /* 49 ** This lookup table is used to help decode the first byte of 50 ** a multi-byte UTF8 character. 51 */ 52 static const unsigned char sqlite3UtfTrans1[] = { 53 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 54 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 55 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 56 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 57 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 58 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 59 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 60 0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00, 61 }; 62 63 64 #define WRITE_UTF8(zOut, c) { \ 65 if( c<0x00080 ){ \ 66 *zOut++ = (c&0xFF); \ 67 } \ 68 else if( c<0x00800 ){ \ 69 *zOut++ = 0xC0 + ((c>>6)&0x1F); \ 70 *zOut++ = 0x80 + (c & 0x3F); \ 71 } \ 72 else if( c<0x10000 ){ \ 73 *zOut++ = 0xE0 + ((c>>12)&0x0F); \ 74 *zOut++ = 0x80 + ((c>>6) & 0x3F); \ 75 *zOut++ = 0x80 + (c & 0x3F); \ 76 }else{ \ 77 *zOut++ = 0xF0 + ((c>>18) & 0x07); \ 78 *zOut++ = 0x80 + ((c>>12) & 0x3F); \ 79 *zOut++ = 0x80 + ((c>>6) & 0x3F); \ 80 *zOut++ = 0x80 + (c & 0x3F); \ 81 } \ 82 } 83 84 #define WRITE_UTF16LE(zOut, c) { \ 85 if( c<=0xFFFF ){ \ 86 *zOut++ = (c&0x00FF); \ 87 *zOut++ = ((c>>8)&0x00FF); \ 88 }else{ \ 89 *zOut++ = (((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \ 90 *zOut++ = (0x00D8 + (((c-0x10000)>>18)&0x03)); \ 91 *zOut++ = (c&0x00FF); \ 92 *zOut++ = (0x00DC + ((c>>8)&0x03)); \ 93 } \ 94 } 95 96 #define WRITE_UTF16BE(zOut, c) { \ 97 if( c<=0xFFFF ){ \ 98 *zOut++ = ((c>>8)&0x00FF); \ 99 *zOut++ = (c&0x00FF); \ 100 }else{ \ 101 *zOut++ = (0x00D8 + (((c-0x10000)>>18)&0x03)); \ 102 *zOut++ = (((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \ 103 *zOut++ = (0x00DC + ((c>>8)&0x03)); \ 104 *zOut++ = (c&0x00FF); \ 105 } \ 106 } 107 108 #define READ_UTF16LE(zIn, c){ \ 109 c = (*zIn++); \ 110 c += ((*zIn++)<<8); \ 111 if( c>=0xD800 && c<0xE000 ){ \ 112 int c2 = (*zIn++); \ 113 c2 += ((*zIn++)<<8); \ 114 c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \ 115 if( (c & 0xFFFF0000)==0 ) c = 0xFFFD; \ 116 } \ 117 } 118 119 #define READ_UTF16BE(zIn, c){ \ 120 c = ((*zIn++)<<8); \ 121 c += (*zIn++); \ 122 if( c>=0xD800 && c<0xE000 ){ \ 123 int c2 = ((*zIn++)<<8); \ 124 c2 += (*zIn++); \ 125 c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \ 126 if( (c & 0xFFFF0000)==0 ) c = 0xFFFD; \ 127 } \ 128 } 129 130 /* 131 ** Translate a single UTF-8 character. Return the unicode value. 132 ** 133 ** During translation, assume that the byte that zTerm points 134 ** is a 0x00. 135 ** 136 ** Write a pointer to the next unread byte back into *pzNext. 137 ** 138 ** Notes On Invalid UTF-8: 139 ** 140 ** * This routine never allows a 7-bit character (0x00 through 0x7f) to 141 ** be encoded as a multi-byte character. Any multi-byte character that 142 ** attempts to encode a value between 0x00 and 0x7f is rendered as 0xfffd. 143 ** 144 ** * This routine never allows a UTF16 surrogate value to be encoded. 145 ** If a multi-byte character attempts to encode a value between 146 ** 0xd800 and 0xe000 then it is rendered as 0xfffd. 147 ** 148 ** * Bytes in the range of 0x80 through 0xbf which occur as the first 149 ** byte of a character are interpreted as single-byte characters 150 ** and rendered as themselves even though they are technically 151 ** invalid characters. 152 ** 153 ** * This routine accepts an infinite number of different UTF8 encodings 154 ** for unicode values 0x80 and greater. It do not change over-length 155 ** encodings to 0xfffd as some systems recommend. 156 */ 157 #define READ_UTF8(zIn, zTerm, c) \ 158 c = *(zIn++); \ 159 if( c>=0xc0 ){ \ 160 c = sqlite3UtfTrans1[c-0xc0]; \ 161 while( zIn!=zTerm && (*zIn & 0xc0)==0x80 ){ \ 162 c = (c<<6) + (0x3f & *(zIn++)); \ 163 } \ 164 if( c<0x80 \ 165 || (c&0xFFFFF800)==0xD800 \ 166 || (c&0xFFFFFFFE)==0xFFFE ){ c = 0xFFFD; } \ 167 } 168 int sqlite3Utf8Read( 169 const unsigned char *z, /* First byte of UTF-8 character */ 170 const unsigned char *zTerm, /* Pretend this byte is 0x00 */ 171 const unsigned char **pzNext /* Write first byte past UTF-8 char here */ 172 ){ 173 int c; 174 READ_UTF8(z, zTerm, c); 175 *pzNext = z; 176 return c; 177 } 178 179 180 181 182 /* 183 ** If the TRANSLATE_TRACE macro is defined, the value of each Mem is 184 ** printed on stderr on the way into and out of sqlite3VdbeMemTranslate(). 185 */ 186 /* #define TRANSLATE_TRACE 1 */ 187 188 #ifndef SQLITE_OMIT_UTF16 189 /* 190 ** This routine transforms the internal text encoding used by pMem to 191 ** desiredEnc. It is an error if the string is already of the desired 192 ** encoding, or if *pMem does not contain a string value. 193 */ 194 int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){ 195 int len; /* Maximum length of output string in bytes */ 196 unsigned char *zOut; /* Output buffer */ 197 unsigned char *zIn; /* Input iterator */ 198 unsigned char *zTerm; /* End of input */ 199 unsigned char *z; /* Output iterator */ 200 unsigned int c; 201 202 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 203 assert( pMem->flags&MEM_Str ); 204 assert( pMem->enc!=desiredEnc ); 205 assert( pMem->enc!=0 ); 206 assert( pMem->n>=0 ); 207 208 #if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG) 209 { 210 char zBuf[100]; 211 sqlite3VdbeMemPrettyPrint(pMem, zBuf); 212 fprintf(stderr, "INPUT: %s\n", zBuf); 213 } 214 #endif 215 216 /* If the translation is between UTF-16 little and big endian, then 217 ** all that is required is to swap the byte order. This case is handled 218 ** differently from the others. 219 */ 220 if( pMem->enc!=SQLITE_UTF8 && desiredEnc!=SQLITE_UTF8 ){ 221 u8 temp; 222 int rc; 223 rc = sqlite3VdbeMemMakeWriteable(pMem); 224 if( rc!=SQLITE_OK ){ 225 assert( rc==SQLITE_NOMEM ); 226 return SQLITE_NOMEM; 227 } 228 zIn = (u8*)pMem->z; 229 zTerm = &zIn[pMem->n]; 230 while( zIn<zTerm ){ 231 temp = *zIn; 232 *zIn = *(zIn+1); 233 zIn++; 234 *zIn++ = temp; 235 } 236 pMem->enc = desiredEnc; 237 goto translate_out; 238 } 239 240 /* Set len to the maximum number of bytes required in the output buffer. */ 241 if( desiredEnc==SQLITE_UTF8 ){ 242 /* When converting from UTF-16, the maximum growth results from 243 ** translating a 2-byte character to a 4-byte UTF-8 character. 244 ** A single byte is required for the output string 245 ** nul-terminator. 246 */ 247 len = pMem->n * 2 + 1; 248 }else{ 249 /* When converting from UTF-8 to UTF-16 the maximum growth is caused 250 ** when a 1-byte UTF-8 character is translated into a 2-byte UTF-16 251 ** character. Two bytes are required in the output buffer for the 252 ** nul-terminator. 253 */ 254 len = pMem->n * 2 + 2; 255 } 256 257 /* Set zIn to point at the start of the input buffer and zTerm to point 1 258 ** byte past the end. 259 ** 260 ** Variable zOut is set to point at the output buffer, space obtained 261 ** from sqlite3_malloc(). 262 */ 263 zIn = (u8*)pMem->z; 264 zTerm = &zIn[pMem->n]; 265 zOut = sqlite3DbMallocRaw(pMem->db, len); 266 if( !zOut ){ 267 return SQLITE_NOMEM; 268 } 269 z = zOut; 270 271 if( pMem->enc==SQLITE_UTF8 ){ 272 if( desiredEnc==SQLITE_UTF16LE ){ 273 /* UTF-8 -> UTF-16 Little-endian */ 274 while( zIn<zTerm ){ 275 /* c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn); */ 276 READ_UTF8(zIn, zTerm, c); 277 WRITE_UTF16LE(z, c); 278 } 279 }else{ 280 assert( desiredEnc==SQLITE_UTF16BE ); 281 /* UTF-8 -> UTF-16 Big-endian */ 282 while( zIn<zTerm ){ 283 /* c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn); */ 284 READ_UTF8(zIn, zTerm, c); 285 WRITE_UTF16BE(z, c); 286 } 287 } 288 pMem->n = z - zOut; 289 *z++ = 0; 290 }else{ 291 assert( desiredEnc==SQLITE_UTF8 ); 292 if( pMem->enc==SQLITE_UTF16LE ){ 293 /* UTF-16 Little-endian -> UTF-8 */ 294 while( zIn<zTerm ){ 295 READ_UTF16LE(zIn, c); 296 WRITE_UTF8(z, c); 297 } 298 }else{ 299 /* UTF-16 Big-endian -> UTF-8 */ 300 while( zIn<zTerm ){ 301 READ_UTF16BE(zIn, c); 302 WRITE_UTF8(z, c); 303 } 304 } 305 pMem->n = z - zOut; 306 } 307 *z = 0; 308 assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len ); 309 310 sqlite3VdbeMemRelease(pMem); 311 pMem->flags &= ~(MEM_Static|MEM_Dyn|MEM_Ephem); 312 pMem->enc = desiredEnc; 313 pMem->flags |= (MEM_Term|MEM_Dyn); 314 pMem->z = (char*)zOut; 315 pMem->zMalloc = pMem->z; 316 317 translate_out: 318 #if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG) 319 { 320 char zBuf[100]; 321 sqlite3VdbeMemPrettyPrint(pMem, zBuf); 322 fprintf(stderr, "OUTPUT: %s\n", zBuf); 323 } 324 #endif 325 return SQLITE_OK; 326 } 327 328 /* 329 ** This routine checks for a byte-order mark at the beginning of the 330 ** UTF-16 string stored in *pMem. If one is present, it is removed and 331 ** the encoding of the Mem adjusted. This routine does not do any 332 ** byte-swapping, it just sets Mem.enc appropriately. 333 ** 334 ** The allocation (static, dynamic etc.) and encoding of the Mem may be 335 ** changed by this function. 336 */ 337 int sqlite3VdbeMemHandleBom(Mem *pMem){ 338 int rc = SQLITE_OK; 339 u8 bom = 0; 340 341 if( pMem->n<0 || pMem->n>1 ){ 342 u8 b1 = *(u8 *)pMem->z; 343 u8 b2 = *(((u8 *)pMem->z) + 1); 344 if( b1==0xFE && b2==0xFF ){ 345 bom = SQLITE_UTF16BE; 346 } 347 if( b1==0xFF && b2==0xFE ){ 348 bom = SQLITE_UTF16LE; 349 } 350 } 351 352 if( bom ){ 353 rc = sqlite3VdbeMemMakeWriteable(pMem); 354 if( rc==SQLITE_OK ){ 355 pMem->n -= 2; 356 memmove(pMem->z, &pMem->z[2], pMem->n); 357 pMem->z[pMem->n] = '\0'; 358 pMem->z[pMem->n+1] = '\0'; 359 pMem->flags |= MEM_Term; 360 pMem->enc = bom; 361 } 362 } 363 return rc; 364 } 365 #endif /* SQLITE_OMIT_UTF16 */ 366 367 /* 368 ** pZ is a UTF-8 encoded unicode string. If nByte is less than zero, 369 ** return the number of unicode characters in pZ up to (but not including) 370 ** the first 0x00 byte. If nByte is not less than zero, return the 371 ** number of unicode characters in the first nByte of pZ (or up to 372 ** the first 0x00, whichever comes first). 373 */ 374 int sqlite3Utf8CharLen(const char *zIn, int nByte){ 375 int r = 0; 376 const u8 *z = (const u8*)zIn; 377 const u8 *zTerm; 378 if( nByte>=0 ){ 379 zTerm = &z[nByte]; 380 }else{ 381 zTerm = (const u8*)(-1); 382 } 383 assert( z<=zTerm ); 384 while( *z!=0 && z<zTerm ){ 385 SQLITE_SKIP_UTF8(z); 386 r++; 387 } 388 return r; 389 } 390 391 /* This test function is not currently used by the automated test-suite. 392 ** Hence it is only available in debug builds. 393 */ 394 #if defined(SQLITE_TEST) && defined(SQLITE_DEBUG) 395 /* 396 ** Translate UTF-8 to UTF-8. 397 ** 398 ** This has the effect of making sure that the string is well-formed 399 ** UTF-8. Miscoded characters are removed. 400 ** 401 ** The translation is done in-place (since it is impossible for the 402 ** correct UTF-8 encoding to be longer than a malformed encoding). 403 */ 404 int sqlite3Utf8To8(unsigned char *zIn){ 405 unsigned char *zOut = zIn; 406 unsigned char *zStart = zIn; 407 unsigned char *zTerm; 408 u32 c; 409 410 while( zIn[0] ){ 411 c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn); 412 if( c!=0xfffd ){ 413 WRITE_UTF8(zOut, c); 414 } 415 } 416 *zOut = 0; 417 return zOut - zStart; 418 } 419 #endif 420 421 #ifndef SQLITE_OMIT_UTF16 422 /* 423 ** Convert a UTF-16 string in the native encoding into a UTF-8 string. 424 ** Memory to hold the UTF-8 string is obtained from sqlite3_malloc and must 425 ** be freed by the calling function. 426 ** 427 ** NULL is returned if there is an allocation error. 428 */ 429 char *sqlite3Utf16to8(sqlite3 *db, const void *z, int nByte){ 430 Mem m; 431 memset(&m, 0, sizeof(m)); 432 m.db = db; 433 sqlite3VdbeMemSetStr(&m, z, nByte, SQLITE_UTF16NATIVE, SQLITE_STATIC); 434 sqlite3VdbeChangeEncoding(&m, SQLITE_UTF8); 435 if( db->mallocFailed ){ 436 sqlite3VdbeMemRelease(&m); 437 m.z = 0; 438 } 439 assert( (m.flags & MEM_Term)!=0 || db->mallocFailed ); 440 assert( (m.flags & MEM_Str)!=0 || db->mallocFailed ); 441 return (m.flags & MEM_Dyn)!=0 ? m.z : sqlite3DbStrDup(db, m.z); 442 } 443 444 /* 445 ** pZ is a UTF-16 encoded unicode string. If nChar is less than zero, 446 ** return the number of bytes up to (but not including), the first pair 447 ** of consecutive 0x00 bytes in pZ. If nChar is not less than zero, 448 ** then return the number of bytes in the first nChar unicode characters 449 ** in pZ (or up until the first pair of 0x00 bytes, whichever comes first). 450 */ 451 int sqlite3Utf16ByteLen(const void *zIn, int nChar){ 452 unsigned int c = 1; 453 char const *z = zIn; 454 int n = 0; 455 if( SQLITE_UTF16NATIVE==SQLITE_UTF16BE ){ 456 /* Using an "if (SQLITE_UTF16NATIVE==SQLITE_UTF16BE)" construct here 457 ** and in other parts of this file means that at one branch will 458 ** not be covered by coverage testing on any single host. But coverage 459 ** will be complete if the tests are run on both a little-endian and 460 ** big-endian host. Because both the UTF16NATIVE and SQLITE_UTF16BE 461 ** macros are constant at compile time the compiler can determine 462 ** which branch will be followed. It is therefore assumed that no runtime 463 ** penalty is paid for this "if" statement. 464 */ 465 while( c && ((nChar<0) || n<nChar) ){ 466 READ_UTF16BE(z, c); 467 n++; 468 } 469 }else{ 470 while( c && ((nChar<0) || n<nChar) ){ 471 READ_UTF16LE(z, c); 472 n++; 473 } 474 } 475 return (z-(char const *)zIn)-((c==0)?2:0); 476 } 477 478 #if defined(SQLITE_TEST) 479 /* 480 ** This routine is called from the TCL test function "translate_selftest". 481 ** It checks that the primitives for serializing and deserializing 482 ** characters in each encoding are inverses of each other. 483 */ 484 void sqlite3UtfSelfTest(){ 485 unsigned int i, t; 486 unsigned char zBuf[20]; 487 unsigned char *z; 488 unsigned char *zTerm; 489 int n; 490 unsigned int c; 491 492 for(i=0; i<0x00110000; i++){ 493 z = zBuf; 494 WRITE_UTF8(z, i); 495 n = z-zBuf; 496 z[0] = 0; 497 zTerm = z; 498 z = zBuf; 499 c = sqlite3Utf8Read(z, zTerm, (const u8**)&z); 500 t = i; 501 if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD; 502 if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD; 503 assert( c==t ); 504 assert( (z-zBuf)==n ); 505 } 506 for(i=0; i<0x00110000; i++){ 507 if( i>=0xD800 && i<0xE000 ) continue; 508 z = zBuf; 509 WRITE_UTF16LE(z, i); 510 n = z-zBuf; 511 z[0] = 0; 512 z = zBuf; 513 READ_UTF16LE(z, c); 514 assert( c==i ); 515 assert( (z-zBuf)==n ); 516 } 517 for(i=0; i<0x00110000; i++){ 518 if( i>=0xD800 && i<0xE000 ) continue; 519 z = zBuf; 520 WRITE_UTF16BE(z, i); 521 n = z-zBuf; 522 z[0] = 0; 523 z = zBuf; 524 READ_UTF16BE(z, c); 525 assert( c==i ); 526 assert( (z-zBuf)==n ); 527 } 528 } 529 #endif /* SQLITE_TEST */ 530 #endif /* SQLITE_OMIT_UTF16 */ 531