/* ** 2004 April 13 ** ** The author disclaims copyright to this source code. In place of ** a legal notice, here is a blessing: ** ** May you do good and not evil. ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ************************************************************************* ** This file contains routines used to translate between UTF-8, ** UTF-16, UTF-16BE, and UTF-16LE. ** ** $Id: utf.c,v 1.1.1.1 2006/02/03 20:35:10 hoganrobert Exp $ ** ** Notes on UTF-8: ** ** Byte-0 Byte-1 Byte-2 Byte-3 Value ** 0xxxxxxx 00000000 00000000 0xxxxxxx ** 110yyyyy 10xxxxxx 00000000 00000yyy yyxxxxxx ** 1110zzzz 10yyyyyy 10xxxxxx 00000000 zzzzyyyy yyxxxxxx ** 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx 000uuuuu zzzzyyyy yyxxxxxx ** ** ** Notes on UTF-16: (with wwww+1==uuuuu) ** ** Word-0 Word-1 Value ** 110110ww wwzzzzyy 110111yy yyxxxxxx 000uuuuu zzzzyyyy yyxxxxxx ** zzzzyyyy yyxxxxxx 00000000 zzzzyyyy yyxxxxxx ** ** ** BOM or Byte Order Mark: ** 0xff 0xfe little-endian utf-16 follows ** 0xfe 0xff big-endian utf-16 follows ** ** ** Handling of malformed strings: ** ** SQLite accepts and processes malformed strings without an error wherever ** possible. However this is not possible when converting between UTF-8 and ** UTF-16. ** ** When converting malformed UTF-8 strings to UTF-16, one instance of the ** replacement character U+FFFD for each byte that cannot be interpeted as ** part of a valid unicode character. ** ** When converting malformed UTF-16 strings to UTF-8, one instance of the ** replacement character U+FFFD for each pair of bytes that cannot be ** interpeted as part of a valid unicode character. ** ** This file contains the following public routines: ** ** sqlite3VdbeMemTranslate() - Translate the encoding used by a Mem* string. ** sqlite3VdbeMemHandleBom() - Handle byte-order-marks in UTF16 Mem* strings. ** sqlite3utf16ByteLen() - Calculate byte-length of a void* UTF16 string. ** sqlite3utf8CharLen() - Calculate char-length of a char* UTF8 string. ** sqlite3utf8LikeCompare() - Do a LIKE match given two UTF8 char* strings. ** */ #include "sqliteInt.h" #include #include "vdbeInt.h" /* ** This table maps from the first byte of a UTF-8 character to the number ** of trailing bytes expected. A value '255' indicates that the table key ** is not a legal first byte for a UTF-8 character. */ static const u8 xtra_utf8_bytes[256] = { /* 0xxxxxxx */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 10wwwwww */ 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, /* 110yyyyy */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 1110zzzz */ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, /* 11110yyy */ 3, 3, 3, 3, 3, 3, 3, 3, 255, 255, 255, 255, 255, 255, 255, 255, }; /* ** This table maps from the number of trailing bytes in a UTF-8 character ** to an integer constant that is effectively calculated for each character ** read by a naive implementation of a UTF-8 character reader. The code ** in the READ_UTF8 macro explains things best. */ static const int xtra_utf8_bits[4] = { 0, 12416, /* (0xC0 << 6) + (0x80) */ 925824, /* (0xE0 << 12) + (0x80 << 6) + (0x80) */ 63447168 /* (0xF0 << 18) + (0x80 << 12) + (0x80 << 6) + 0x80 */ }; #define READ_UTF8(zIn, c) { \ int xtra; \ c = *(zIn)++; \ xtra = xtra_utf8_bytes[c]; \ switch( xtra ){ \ case 255: c = (int)0xFFFD; break; \ case 3: c = (c<<6) + *(zIn)++; \ case 2: c = (c<<6) + *(zIn)++; \ case 1: c = (c<<6) + *(zIn)++; \ c -= xtra_utf8_bits[xtra]; \ } \ } int sqlite3ReadUtf8(const unsigned char *z){ int c; READ_UTF8(z, c); return c; } #define SKIP_UTF8(zIn) { \ zIn += (xtra_utf8_bytes[*(u8 *)zIn] + 1); \ } #define WRITE_UTF8(zOut, c) { \ if( c<0x00080 ){ \ *zOut++ = (c&0xFF); \ } \ else if( c<0x00800 ){ \ *zOut++ = 0xC0 + ((c>>6)&0x1F); \ *zOut++ = 0x80 + (c & 0x3F); \ } \ else if( c<0x10000 ){ \ *zOut++ = 0xE0 + ((c>>12)&0x0F); \ *zOut++ = 0x80 + ((c>>6) & 0x3F); \ *zOut++ = 0x80 + (c & 0x3F); \ }else{ \ *zOut++ = 0xF0 + ((c>>18) & 0x07); \ *zOut++ = 0x80 + ((c>>12) & 0x3F); \ *zOut++ = 0x80 + ((c>>6) & 0x3F); \ *zOut++ = 0x80 + (c & 0x3F); \ } \ } #define WRITE_UTF16LE(zOut, c) { \ if( c<=0xFFFF ){ \ *zOut++ = (c&0x00FF); \ *zOut++ = ((c>>8)&0x00FF); \ }else{ \ *zOut++ = (((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \ *zOut++ = (0x00D8 + (((c-0x10000)>>18)&0x03)); \ *zOut++ = (c&0x00FF); \ *zOut++ = (0x00DC + ((c>>8)&0x03)); \ } \ } #define WRITE_UTF16BE(zOut, c) { \ if( c<=0xFFFF ){ \ *zOut++ = ((c>>8)&0x00FF); \ *zOut++ = (c&0x00FF); \ }else{ \ *zOut++ = (0x00D8 + (((c-0x10000)>>18)&0x03)); \ *zOut++ = (((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \ *zOut++ = (0x00DC + ((c>>8)&0x03)); \ *zOut++ = (c&0x00FF); \ } \ } #define READ_UTF16LE(zIn, c){ \ c = (*zIn++); \ c += ((*zIn++)<<8); \ if( c>=0xD800 && c<=0xE000 ){ \ int c2 = (*zIn++); \ c2 += ((*zIn++)<<8); \ c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \ } \ } #define READ_UTF16BE(zIn, c){ \ c = ((*zIn++)<<8); \ c += (*zIn++); \ if( c>=0xD800 && c<=0xE000 ){ \ int c2 = ((*zIn++)<<8); \ c2 += (*zIn++); \ c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \ } \ } #define SKIP_UTF16BE(zIn){ \ if( *zIn>=0xD8 && (*zIn<0xE0 || (*zIn==0xE0 && *(zIn+1)==0x00)) ){ \ zIn += 4; \ }else{ \ zIn += 2; \ } \ } #define SKIP_UTF16LE(zIn){ \ zIn++; \ if( *zIn>=0xD8 && (*zIn<0xE0 || (*zIn==0xE0 && *(zIn-1)==0x00)) ){ \ zIn += 3; \ }else{ \ zIn += 1; \ } \ } #define RSKIP_UTF16LE(zIn){ \ if( *zIn>=0xD8 && (*zIn<0xE0 || (*zIn==0xE0 && *(zIn-1)==0x00)) ){ \ zIn -= 4; \ }else{ \ zIn -= 2; \ } \ } #define RSKIP_UTF16BE(zIn){ \ zIn--; \ if( *zIn>=0xD8 && (*zIn<0xE0 || (*zIn==0xE0 && *(zIn+1)==0x00)) ){ \ zIn -= 3; \ }else{ \ zIn -= 1; \ } \ } /* ** If the TRANSLATE_TRACE macro is defined, the value of each Mem is ** printed on stderr on the way into and out of sqlite3VdbeMemTranslate(). */ /* #define TRANSLATE_TRACE 1 */ #ifndef SQLITE_OMIT_UTF16 /* ** This routine transforms the internal text encoding used by pMem to ** desiredEnc. It is an error if the string is already of the desired ** encoding, or if *pMem does not contain a string value. */ int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){ unsigned char zShort[NBFS]; /* Temporary short output buffer */ int len; /* Maximum length of output string in bytes */ unsigned char *zOut; /* Output buffer */ unsigned char *zIn; /* Input iterator */ unsigned char *zTerm; /* End of input */ unsigned char *z; /* Output iterator */ int c; assert( pMem->flags&MEM_Str ); assert( pMem->enc!=desiredEnc ); assert( pMem->enc!=0 ); assert( pMem->n>=0 ); #if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG) { char zBuf[100]; sqlite3VdbeMemPrettyPrint(pMem, zBuf, 100); fprintf(stderr, "INPUT: %s\n", zBuf); } #endif /* If the translation is between UTF-16 little and big endian, then ** all that is required is to swap the byte order. This case is handled ** differently from the others. */ if( pMem->enc!=SQLITE_UTF8 && desiredEnc!=SQLITE_UTF8 ){ u8 temp; int rc; rc = sqlite3VdbeMemMakeWriteable(pMem); if( rc!=SQLITE_OK ){ assert( rc==SQLITE_NOMEM ); return SQLITE_NOMEM; } zIn = pMem->z; zTerm = &zIn[pMem->n]; while( zInenc = desiredEnc; goto translate_out; } /* Set len to the maximum number of bytes required in the output buffer. */ if( desiredEnc==SQLITE_UTF8 ){ /* When converting from UTF-16, the maximum growth results from ** translating a 2-byte character to a 3-byte UTF-8 character (i.e. ** code-point 0xFFFC). A single byte is required for the output string ** nul-terminator. */ len = (pMem->n/2) * 3 + 1; }else{ /* When converting from UTF-8 to UTF-16 the maximum growth is caused ** when a 1-byte UTF-8 character is translated into a 2-byte UTF-16 ** character. Two bytes are required in the output buffer for the ** nul-terminator. */ len = pMem->n * 2 + 2; } /* Set zIn to point at the start of the input buffer and zTerm to point 1 ** byte past the end. ** ** Variable zOut is set to point at the output buffer. This may be space ** obtained from malloc(), or Mem.zShort, if it large enough and not in ** use, or the zShort array on the stack (see above). */ zIn = pMem->z; zTerm = &zIn[pMem->n]; if( len>NBFS ){ zOut = sqliteMallocRaw(len); if( !zOut ) return SQLITE_NOMEM; }else{ zOut = zShort; } z = zOut; if( pMem->enc==SQLITE_UTF8 ){ if( desiredEnc==SQLITE_UTF16LE ){ /* UTF-8 -> UTF-16 Little-endian */ while( zIn UTF-16 Big-endian */ while( zInn = z - zOut; *z++ = 0; }else{ assert( desiredEnc==SQLITE_UTF8 ); if( pMem->enc==SQLITE_UTF16LE ){ /* UTF-16 Little-endian -> UTF-8 */ while( zIn UTF-8 */ while( zInn = z - zOut; } *z = 0; assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len ); sqlite3VdbeMemRelease(pMem); pMem->flags &= ~(MEM_Static|MEM_Dyn|MEM_Ephem|MEM_Short); pMem->enc = desiredEnc; if( zOut==zShort ){ memcpy(pMem->zShort, zOut, len); zOut = pMem->zShort; pMem->flags |= (MEM_Term|MEM_Short); }else{ pMem->flags |= (MEM_Term|MEM_Dyn); } pMem->z = zOut; translate_out: #if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG) { char zBuf[100]; sqlite3VdbeMemPrettyPrint(pMem, zBuf, 100); fprintf(stderr, "OUTPUT: %s\n", zBuf); } #endif return SQLITE_OK; } /* ** This routine checks for a byte-order mark at the beginning of the ** UTF-16 string stored in *pMem. If one is present, it is removed and ** the encoding of the Mem adjusted. This routine does not do any ** byte-swapping, it just sets Mem.enc appropriately. ** ** The allocation (static, dynamic etc.) and encoding of the Mem may be ** changed by this function. */ int sqlite3VdbeMemHandleBom(Mem *pMem){ int rc = SQLITE_OK; u8 bom = 0; if( pMem->n<0 || pMem->n>1 ){ u8 b1 = *(u8 *)pMem->z; u8 b2 = *(((u8 *)pMem->z) + 1); if( b1==0xFE && b2==0xFF ){ bom = SQLITE_UTF16BE; } if( b1==0xFF && b2==0xFE ){ bom = SQLITE_UTF16LE; } } if( bom ){ /* This function is called as soon as a string is stored in a Mem*, ** from within sqlite3VdbeMemSetStr(). At that point it is not possible ** for the string to be stored in Mem.zShort, or for it to be stored ** in dynamic memory with no destructor. */ assert( !(pMem->flags&MEM_Short) ); assert( !(pMem->flags&MEM_Dyn) || pMem->xDel ); if( pMem->flags & MEM_Dyn ){ void (*xDel)(void*) = pMem->xDel; char *z = pMem->z; pMem->z = 0; pMem->xDel = 0; rc = sqlite3VdbeMemSetStr(pMem, &z[2], pMem->n-2, bom, SQLITE_TRANSIENT); xDel(z); }else{ rc = sqlite3VdbeMemSetStr(pMem, &pMem->z[2], pMem->n-2, bom, SQLITE_TRANSIENT); } } return rc; } #endif /* SQLITE_OMIT_UTF16 */ /* ** pZ is a UTF-8 encoded unicode string. If nByte is less than zero, ** return the number of unicode characters in pZ up to (but not including) ** the first 0x00 byte. If nByte is not less than zero, return the ** number of unicode characters in the first nByte of pZ (or up to ** the first 0x00, whichever comes first). */ int sqlite3utf8CharLen(const char *z, int nByte){ int r = 0; const char *zTerm; if( nByte>=0 ){ zTerm = &z[nByte]; }else{ zTerm = (const char *)(-1); } assert( z<=zTerm ); while( *z!=0 && z0 ){ y = y-1; zStart = zStr; if( SQLITE_UTF16BE==SQLITE_UTF16NATIVE ){ for(i=0; izStr; i++) RSKIP_UTF16BE(zStart); }else{ for(i=y; i<0 && zStart>zStr; i++) RSKIP_UTF16LE(zStart); } for(; i<0; i++) z -= 1; } zEnd = zStart; if( SQLITE_UTF16BE==SQLITE_UTF16NATIVE ){ for(i=0; i=0xD800 && i<=0xE000 ) continue; z = zBuf; WRITE_UTF16LE(z, i); n = z-zBuf; z = zBuf; READ_UTF16LE(z, c); assert( c==i ); assert( (z-zBuf)==n ); } for(i=0; i<0x00110000; i++){ if( i>=0xD800 && i<=0xE000 ) continue; z = zBuf; WRITE_UTF16BE(z, i); n = z-zBuf; z = zBuf; READ_UTF16BE(z, c); assert( c==i ); assert( (z-zBuf)==n ); } } #endif /* SQLITE_TEST */ #endif /* SQLITE_OMIT_UTF16 */