///* // * Copyright 2001-2004 Unicode, Inc. // * // * Disclaimer // * // * This source code is provided as is by Unicode, Inc. No claims are // * made as to fitness for any particular purpose. No warranties of any // * kind are expressed or implied. The recipient agrees to determine // * applicability of information provided. If this file has been // * purchased on magnetic or optical media from Unicode, Inc., the // * sole remedy for any claim will be exchange of defective media // * within 90 days of receipt. // * // * Limitations on Rights to Redistribute This Code // * // * Unicode, Inc. hereby grants the right to freely use the information // * supplied in this file in the creation of products supporting the // * Unicode Standard, and to make copies of this file in any form // * for internal or external distribution as long as this notice // * remains attached. // */ // ///* --------------------------------------------------------------------- // // Conversions between UTF32, UTF-16, and UTF-8. Source code file. // Author: Mark E. Davis, 1994. // Rev History: Rick McGowan, fixes & updates May 2001. // Sept 2001: fixed const & error conditions per // mods suggested by S. Parent & A. Lillich. // June 2002: Tim Dodd added detection and handling of incomplete // source sequences, enhanced error detection, added casts // to eliminate compiler warnings. // July 2003: slight mods to back out aggressive FFFE detection. // Jan 2004: updated switches in from-UTF8 conversions. // Oct 2004: updated to use UNI_MAX_LEGAL_UTF32 in UTF-32 conversions. // // See the header file "ConvertUTF.h" for complete documentation. // //------------------------------------------------------------------------ */ // // //#include "simpleini/ConvertUTF.h" //#ifdef CVTUTF_DEBUG //#include //#endif // //static const int halfShift = 10; /* used for shifting by 10 bits */ // //static const UTF32 halfBase = 0x0010000UL; //static const UTF32 halfMask = 0x3FFUL; // //#define UNI_SUR_HIGH_START (UTF32)0xD800 //#define UNI_SUR_HIGH_END (UTF32)0xDBFF //#define UNI_SUR_LOW_START (UTF32)0xDC00 //#define UNI_SUR_LOW_END (UTF32)0xDFFF //#define false 0 //#define true 1 // ///* --------------------------------------------------------------------- */ // //ConversionResult ConvertUTF32toUTF16 ( // const UTF32** sourceStart, const UTF32* sourceEnd, // UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags) { // ConversionResult result = conversionOK; // const UTF32* source = *sourceStart; // UTF16* target = *targetStart; // while (source < sourceEnd) { // UTF32 ch; // if (target >= targetEnd) { // result = targetExhausted; break; // } // ch = *source++; // if (ch <= UNI_MAX_BMP) { /* Target is a character <= 0xFFFF */ // /* UTF-16 surrogate values are illegal in UTF-32; 0xffff or 0xfffe are both reserved values */ // if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) { // if (flags == strictConversion) { // --source; /* return to the illegal value itself */ // result = sourceIllegal; // break; // } else { // *target++ = UNI_REPLACEMENT_CHAR; // } // } else { // *target++ = (UTF16)ch; /* normal case */ // } // } else if (ch > UNI_MAX_LEGAL_UTF32) { // if (flags == strictConversion) { // result = sourceIllegal; // } else { // *target++ = UNI_REPLACEMENT_CHAR; // } // } else { // /* target is a character in range 0xFFFF - 0x10FFFF. */ // if (target + 1 >= targetEnd) { // --source; /* Back up source pointer! */ // result = targetExhausted; break; // } // ch -= halfBase; // *target++ = (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START); // *target++ = (UTF16)((ch & halfMask) + UNI_SUR_LOW_START); // } // } // *sourceStart = source; // *targetStart = target; // return result; //} // ///* --------------------------------------------------------------------- */ // //ConversionResult ConvertUTF16toUTF32 ( // const UTF16** sourceStart, const UTF16* sourceEnd, // UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags) { // ConversionResult result = conversionOK; // const UTF16* source = *sourceStart; // UTF32* target = *targetStart; // UTF32 ch, ch2; // while (source < sourceEnd) { // const UTF16* oldSource = source; /* In case we have to back up because of target overflow. */ // ch = *source++; // /* If we have a surrogate pair, convert to UTF32 first. */ // if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) { // /* If the 16 bits following the high surrogate are in the source buffer... */ // if (source < sourceEnd) { // ch2 = *source; // /* If it's a low surrogate, convert to UTF32. */ // if (ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END) { // ch = ((ch - UNI_SUR_HIGH_START) << halfShift) // + (ch2 - UNI_SUR_LOW_START) + halfBase; // ++source; // } else if (flags == strictConversion) { /* it's an unpaired high surrogate */ // --source; /* return to the illegal value itself */ // result = sourceIllegal; // break; // } // } else { /* We don't have the 16 bits following the high surrogate. */ // --source; /* return to the high surrogate */ // result = sourceExhausted; // break; // } // } else if (flags == strictConversion) { // /* UTF-16 surrogate values are illegal in UTF-32 */ // if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) { // --source; /* return to the illegal value itself */ // result = sourceIllegal; // break; // } // } // if (target >= targetEnd) { // source = oldSource; /* Back up source pointer! */ // result = targetExhausted; break; // } // *target++ = ch; // } // *sourceStart = source; // *targetStart = target; //#ifdef CVTUTF_DEBUG //if (result == sourceIllegal) { // fprintf(stderr, "ConvertUTF16toUTF32 illegal seq 0x%04x,%04x\n", ch, ch2); // fflush(stderr); //} //#endif // return result; //} // ///* --------------------------------------------------------------------- */ // ///* // * Index into the table below with the first byte of a UTF-8 sequence to // * get the number of trailing bytes that are supposed to follow it. // * Note that *legal* UTF-8 values can't have 4 or 5-bytes. The table is // * left as-is for anyone who may want to do such conversion, which was // * allowed in earlier algorithms. // */ //static const char trailingBytesForUTF8[256] = { // 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, // 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, // 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, // 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 //}; // ///* // * Magic values subtracted from a buffer value during UTF8 conversion. // * This table contains as many values as there might be trailing bytes // * in a UTF-8 sequence. // */ //static const UTF32 offsetsFromUTF8[6] = { 0x00000000UL, 0x00003080UL, 0x000E2080UL, // 0x03C82080UL, 0xFA082080UL, 0x82082080UL }; // ///* // * Once the bits are split out into bytes of UTF-8, this is a mask OR-ed // * into the first byte, depending on how many bytes follow. There are // * as many entries in this table as there are UTF-8 sequence types. // * (I.e., one byte sequence, two byte... etc.). Remember that sequences // * for *legal* UTF-8 will be 4 or fewer bytes total. // */ //static const UTF8 firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC }; // ///* --------------------------------------------------------------------- */ // ///* The interface converts a whole buffer to avoid function-call overhead. // * Constants have been gathered. Loops & conditionals have been removed as // * much as possible for efficiency, in favor of drop-through switches. // * (See "Note A" at the bottom of the file for equivalent code.) // * If your compiler supports it, the "isLegalUTF8" call can be turned // * into an inline function. // */ // ///* --------------------------------------------------------------------- */ // //ConversionResult ConvertUTF16toUTF8 ( // const UTF16** sourceStart, const UTF16* sourceEnd, // UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags) { // ConversionResult result = conversionOK; // const UTF16* source = *sourceStart; // UTF8* target = *targetStart; // while (source < sourceEnd) { // UTF32 ch; // unsigned short bytesToWrite = 0; // const UTF32 byteMask = 0xBF; // const UTF32 byteMark = 0x80; // const UTF16* oldSource = source; /* In case we have to back up because of target overflow. */ // ch = *source++; // /* If we have a surrogate pair, convert to UTF32 first. */ // if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) { // /* If the 16 bits following the high surrogate are in the source buffer... */ // if (source < sourceEnd) { // UTF32 ch2 = *source; // /* If it's a low surrogate, convert to UTF32. */ // if (ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END) { // ch = ((ch - UNI_SUR_HIGH_START) << halfShift) // + (ch2 - UNI_SUR_LOW_START) + halfBase; // ++source; // } else if (flags == strictConversion) { /* it's an unpaired high surrogate */ // --source; /* return to the illegal value itself */ // result = sourceIllegal; // break; // } // } else { /* We don't have the 16 bits following the high surrogate. */ // --source; /* return to the high surrogate */ // result = sourceExhausted; // break; // } // } else if (flags == strictConversion) { // /* UTF-16 surrogate values are illegal in UTF-32 */ // if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) { // --source; /* return to the illegal value itself */ // result = sourceIllegal; // break; // } // } // /* Figure out how many bytes the result will require */ // if (ch < (UTF32)0x80) { bytesToWrite = 1; // } else if (ch < (UTF32)0x800) { bytesToWrite = 2; // } else if (ch < (UTF32)0x10000) { bytesToWrite = 3; // } else if (ch < (UTF32)0x110000) { bytesToWrite = 4; // } else { bytesToWrite = 3; // ch = UNI_REPLACEMENT_CHAR; // } // // target += bytesToWrite; // if (target > targetEnd) { // source = oldSource; /* Back up source pointer! */ // target -= bytesToWrite; result = targetExhausted; break; // } // switch (bytesToWrite) { /* note: everything falls through. */ // case 4: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6; // case 3: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6; // case 2: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6; // case 1: *--target = (UTF8)(ch | firstByteMark[bytesToWrite]); // } // target += bytesToWrite; // } // *sourceStart = source; // *targetStart = target; // return result; //} // ///* --------------------------------------------------------------------- */ // ///* // * Utility routine to tell whether a sequence of bytes is legal UTF-8. // * This must be called with the length pre-determined by the first byte. // * If not calling this from ConvertUTF8to*, then the length can be set by: // * length = trailingBytesForUTF8[*source]+1; // * and the sequence is illegal right away if there aren't that many bytes // * available. // * If presented with a length > 4, this returns false. The Unicode // * definition of UTF-8 goes up to 4-byte sequences. // */ // //static Boolean isLegalUTF8(const UTF8 *source, int length) { // UTF8 a; // const UTF8 *srcptr = source+length; // switch (length) { // default: return false; // /* Everything else falls through when "true"... */ // case 4: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false; // case 3: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false; // case 2: if ((a = (*--srcptr)) > 0xBF) return false; // // switch (*source) { // /* no fall-through in this inner switch */ // case 0xE0: if (a < 0xA0) return false; break; // case 0xED: if (a > 0x9F) return false; break; // case 0xF0: if (a < 0x90) return false; break; // case 0xF4: if (a > 0x8F) return false; break; // default: if (a < 0x80) return false; // } // // case 1: if (*source >= 0x80 && *source < 0xC2) return false; // } // if (*source > 0xF4) return false; // return true; //} // ///* --------------------------------------------------------------------- */ // ///* // * Exported function to return whether a UTF-8 sequence is legal or not. // * This is not used here; it's just exported. // */ //Boolean isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd) { // int length = trailingBytesForUTF8[*source]+1; // if (source+length > sourceEnd) { // return false; // } // return isLegalUTF8(source, length); //} // ///* --------------------------------------------------------------------- */ // //ConversionResult ConvertUTF8toUTF16 ( // const UTF8** sourceStart, const UTF8* sourceEnd, // UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags) { // ConversionResult result = conversionOK; // const UTF8* source = *sourceStart; // UTF16* target = *targetStart; // while (source < sourceEnd) { // UTF32 ch = 0; // unsigned short extraBytesToRead = trailingBytesForUTF8[*source]; // if (source + extraBytesToRead >= sourceEnd) { // result = sourceExhausted; break; // } // /* Do this check whether lenient or strict */ // if (! isLegalUTF8(source, extraBytesToRead+1)) { // result = sourceIllegal; // break; // } // /* // * The cases all fall through. See "Note A" below. // */ // switch (extraBytesToRead) { // case 5: ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */ // case 4: ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */ // case 3: ch += *source++; ch <<= 6; // case 2: ch += *source++; ch <<= 6; // case 1: ch += *source++; ch <<= 6; // case 0: ch += *source++; // } // ch -= offsetsFromUTF8[extraBytesToRead]; // // if (target >= targetEnd) { // source -= (extraBytesToRead+1); /* Back up source pointer! */ // result = targetExhausted; break; // } // if (ch <= UNI_MAX_BMP) { /* Target is a character <= 0xFFFF */ // /* UTF-16 surrogate values are illegal in UTF-32 */ // if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) { // if (flags == strictConversion) { // source -= (extraBytesToRead+1); /* return to the illegal value itself */ // result = sourceIllegal; // break; // } else { // *target++ = UNI_REPLACEMENT_CHAR; // } // } else { // *target++ = (UTF16)ch; /* normal case */ // } // } else if (ch > UNI_MAX_UTF16) { // if (flags == strictConversion) { // result = sourceIllegal; // source -= (extraBytesToRead+1); /* return to the start */ // break; /* Bail out; shouldn't continue */ // } else { // *target++ = UNI_REPLACEMENT_CHAR; // } // } else { // /* target is a character in range 0xFFFF - 0x10FFFF. */ // if (target + 1 >= targetEnd) { // source -= (extraBytesToRead+1); /* Back up source pointer! */ // result = targetExhausted; break; // } // ch -= halfBase; // *target++ = (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START); // *target++ = (UTF16)((ch & halfMask) + UNI_SUR_LOW_START); // } // } // *sourceStart = source; // *targetStart = target; // return result; //} // ///* --------------------------------------------------------------------- */ // //ConversionResult ConvertUTF32toUTF8 ( // const UTF32** sourceStart, const UTF32* sourceEnd, // UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags) { // ConversionResult result = conversionOK; // const UTF32* source = *sourceStart; // UTF8* target = *targetStart; // while (source < sourceEnd) { // UTF32 ch; // unsigned short bytesToWrite = 0; // const UTF32 byteMask = 0xBF; // const UTF32 byteMark = 0x80; // ch = *source++; // if (flags == strictConversion ) { // /* UTF-16 surrogate values are illegal in UTF-32 */ // if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) { // --source; /* return to the illegal value itself */ // result = sourceIllegal; // break; // } // } // /* // * Figure out how many bytes the result will require. Turn any // * illegally large UTF32 things (> Plane 17) into replacement chars. // */ // if (ch < (UTF32)0x80) { bytesToWrite = 1; // } else if (ch < (UTF32)0x800) { bytesToWrite = 2; // } else if (ch < (UTF32)0x10000) { bytesToWrite = 3; // } else if (ch <= UNI_MAX_LEGAL_UTF32) { bytesToWrite = 4; // } else { bytesToWrite = 3; // ch = UNI_REPLACEMENT_CHAR; // result = sourceIllegal; // } // // target += bytesToWrite; // if (target > targetEnd) { // --source; /* Back up source pointer! */ // target -= bytesToWrite; result = targetExhausted; break; // } // switch (bytesToWrite) { /* note: everything falls through. */ // case 4: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6; // case 3: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6; // case 2: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6; // case 1: *--target = (UTF8) (ch | firstByteMark[bytesToWrite]); // } // target += bytesToWrite; // } // *sourceStart = source; // *targetStart = target; // return result; //} // ///* --------------------------------------------------------------------- */ // //ConversionResult ConvertUTF8toUTF32 ( // const UTF8** sourceStart, const UTF8* sourceEnd, // UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags) { // ConversionResult result = conversionOK; // const UTF8* source = *sourceStart; // UTF32* target = *targetStart; // while (source < sourceEnd) { // UTF32 ch = 0; // unsigned short extraBytesToRead = trailingBytesForUTF8[*source]; // if (source + extraBytesToRead >= sourceEnd) { // result = sourceExhausted; break; // } // /* Do this check whether lenient or strict */ // if (! isLegalUTF8(source, extraBytesToRead+1)) { // result = sourceIllegal; // break; // } // /* // * The cases all fall through. See "Note A" below. // */ // switch (extraBytesToRead) { // case 5: ch += *source++; ch <<= 6; // case 4: ch += *source++; ch <<= 6; // case 3: ch += *source++; ch <<= 6; // case 2: ch += *source++; ch <<= 6; // case 1: ch += *source++; ch <<= 6; // case 0: ch += *source++; // } // ch -= offsetsFromUTF8[extraBytesToRead]; // // if (target >= targetEnd) { // source -= (extraBytesToRead+1); /* Back up the source pointer! */ // result = targetExhausted; break; // } // if (ch <= UNI_MAX_LEGAL_UTF32) { // /* // * UTF-16 surrogate values are illegal in UTF-32, and anything // * over Plane 17 (> 0x10FFFF) is illegal. // */ // if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) { // if (flags == strictConversion) { // source -= (extraBytesToRead+1); /* return to the illegal value itself */ // result = sourceIllegal; // break; // } else { // *target++ = UNI_REPLACEMENT_CHAR; // } // } else { // *target++ = ch; // } // } else { /* i.e., ch > UNI_MAX_LEGAL_UTF32 */ // result = sourceIllegal; // *target++ = UNI_REPLACEMENT_CHAR; // } // } // *sourceStart = source; // *targetStart = target; // return result; //} // ///* --------------------------------------------------------------------- // // Note A. // The fall-through switches in UTF-8 reading code save a // temp variable, some decrements & conditionals. The switches // are equivalent to the following loop: // { // int tmpBytesToRead = extraBytesToRead+1; // do { // ch += *source++; // --tmpBytesToRead; // if (tmpBytesToRead) ch <<= 6; // } while (tmpBytesToRead > 0); // } // In UTF-8 writing code, the switches on "bytesToWrite" are // similarly unrolled loops. // // --------------------------------------------------------------------- */