1 /*===--- ConvertUTF.h - Universal Character Names conversions ---------------=== 2 * 3 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 * See https://llvm.org/LICENSE.txt for license information. 5 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 * 7 *==------------------------------------------------------------------------==*/ 8 /* 9 * Copyright 2001-2004 Unicode, Inc. 10 * 11 * Disclaimer 12 * 13 * This source code is provided as is by Unicode, Inc. No claims are 14 * made as to fitness for any particular purpose. No warranties of any 15 * kind are expressed or implied. The recipient agrees to determine 16 * applicability of information provided. If this file has been 17 * purchased on magnetic or optical media from Unicode, Inc., the 18 * sole remedy for any claim will be exchange of defective media 19 * within 90 days of receipt. 20 * 21 * Limitations on Rights to Redistribute This Code 22 * 23 * Unicode, Inc. hereby grants the right to freely use the information 24 * supplied in this file in the creation of products supporting the 25 * Unicode Standard, and to make copies of this file in any form 26 * for internal or external distribution as long as this notice 27 * remains attached. 28 */ 29 30 /* --------------------------------------------------------------------- 31 32 Conversions between UTF32, UTF-16, and UTF-8. Header file. 33 34 Several funtions are included here, forming a complete set of 35 conversions between the three formats. UTF-7 is not included 36 here, but is handled in a separate source file. 37 38 Each of these routines takes pointers to input buffers and output 39 buffers. The input buffers are const. 40 41 Each routine converts the text between *sourceStart and sourceEnd, 42 putting the result into the buffer between *targetStart and 43 targetEnd. Note: the end pointers are *after* the last item: e.g. 44 *(sourceEnd - 1) is the last item. 45 46 The return result indicates whether the conversion was successful, 47 and if not, whether the problem was in the source or target buffers. 48 (Only the first encountered problem is indicated.) 49 50 After the conversion, *sourceStart and *targetStart are both 51 updated to point to the end of last text successfully converted in 52 the respective buffers. 53 54 Input parameters: 55 sourceStart - pointer to a pointer to the source buffer. 56 The contents of this are modified on return so that 57 it points at the next thing to be converted. 58 targetStart - similarly, pointer to pointer to the target buffer. 59 sourceEnd, targetEnd - respectively pointers to the ends of the 60 two buffers, for overflow checking only. 61 62 These conversion functions take a ConversionFlags argument. When this 63 flag is set to strict, both irregular sequences and isolated surrogates 64 will cause an error. When the flag is set to lenient, both irregular 65 sequences and isolated surrogates are converted. 66 67 Whether the flag is strict or lenient, all illegal sequences will cause 68 an error return. This includes sequences such as: <F4 90 80 80>, <C0 80>, 69 or <A0> in UTF-8, and values above 0x10FFFF in UTF-32. Conformant code 70 must check for illegal sequences. 71 72 When the flag is set to lenient, characters over 0x10FFFF are converted 73 to the replacement character; otherwise (when the flag is set to strict) 74 they constitute an error. 75 76 Output parameters: 77 The value "sourceIllegal" is returned from some routines if the input 78 sequence is malformed. When "sourceIllegal" is returned, the source 79 value will point to the illegal value that caused the problem. E.g., 80 in UTF-8 when a sequence is malformed, it points to the start of the 81 malformed sequence. 82 83 Author: Mark E. Davis, 1994. 84 Rev History: Rick McGowan, fixes & updates May 2001. 85 Fixes & updates, Sept 2001. 86 87 ------------------------------------------------------------------------ */ 88 89 #ifndef LLVM_SUPPORT_CONVERTUTF_H 90 #define LLVM_SUPPORT_CONVERTUTF_H 91 92 #include <cstddef> 93 #include <string> 94 95 #if defined(_WIN32) 96 #include <system_error> 97 #endif 98 99 // Wrap everything in namespace llvm so that programs can link with llvm and 100 // their own version of the unicode libraries. 101 102 namespace llvm { 103 104 /* --------------------------------------------------------------------- 105 The following 4 definitions are compiler-specific. 106 The C standard does not guarantee that wchar_t has at least 107 16 bits, so wchar_t is no less portable than unsigned short! 108 All should be unsigned values to avoid sign extension during 109 bit mask & shift operations. 110 ------------------------------------------------------------------------ */ 111 112 typedef unsigned int UTF32; /* at least 32 bits */ 113 typedef unsigned short UTF16; /* at least 16 bits */ 114 typedef unsigned char UTF8; /* typically 8 bits */ 115 typedef unsigned char Boolean; /* 0 or 1 */ 116 117 /* Some fundamental constants */ 118 #define UNI_REPLACEMENT_CHAR (UTF32)0x0000FFFD 119 #define UNI_MAX_BMP (UTF32)0x0000FFFF 120 #define UNI_MAX_UTF16 (UTF32)0x0010FFFF 121 #define UNI_MAX_UTF32 (UTF32)0x7FFFFFFF 122 #define UNI_MAX_LEGAL_UTF32 (UTF32)0x0010FFFF 123 124 #define UNI_MAX_UTF8_BYTES_PER_CODE_POINT 4 125 126 #define UNI_UTF16_BYTE_ORDER_MARK_NATIVE 0xFEFF 127 #define UNI_UTF16_BYTE_ORDER_MARK_SWAPPED 0xFFFE 128 129 typedef enum { 130 conversionOK, /* conversion successful */ 131 sourceExhausted, /* partial character in source, but hit end */ 132 targetExhausted, /* insuff. room in target for conversion */ 133 sourceIllegal /* source sequence is illegal/malformed */ 134 } ConversionResult; 135 136 typedef enum { 137 strictConversion = 0, 138 lenientConversion 139 } ConversionFlags; 140 141 ConversionResult ConvertUTF8toUTF16 ( 142 const UTF8** sourceStart, const UTF8* sourceEnd, 143 UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags); 144 145 /** 146 * Convert a partial UTF8 sequence to UTF32. If the sequence ends in an 147 * incomplete code unit sequence, returns \c sourceExhausted. 148 */ 149 ConversionResult ConvertUTF8toUTF32Partial( 150 const UTF8** sourceStart, const UTF8* sourceEnd, 151 UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags); 152 153 /** 154 * Convert a partial UTF8 sequence to UTF32. If the sequence ends in an 155 * incomplete code unit sequence, returns \c sourceIllegal. 156 */ 157 ConversionResult ConvertUTF8toUTF32( 158 const UTF8** sourceStart, const UTF8* sourceEnd, 159 UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags); 160 161 ConversionResult ConvertUTF16toUTF8 ( 162 const UTF16** sourceStart, const UTF16* sourceEnd, 163 UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags); 164 165 ConversionResult ConvertUTF32toUTF8 ( 166 const UTF32** sourceStart, const UTF32* sourceEnd, 167 UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags); 168 169 ConversionResult ConvertUTF16toUTF32 ( 170 const UTF16** sourceStart, const UTF16* sourceEnd, 171 UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags); 172 173 ConversionResult ConvertUTF32toUTF16 ( 174 const UTF32** sourceStart, const UTF32* sourceEnd, 175 UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags); 176 177 Boolean isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd); 178 179 Boolean isLegalUTF8String(const UTF8 **source, const UTF8 *sourceEnd); 180 181 unsigned getNumBytesForUTF8(UTF8 firstByte); 182 183 /*************************************************************************/ 184 /* Below are LLVM-specific wrappers of the functions above. */ 185 186 template <typename T> class ArrayRef; 187 template <typename T> class SmallVectorImpl; 188 class StringRef; 189 190 /** 191 * Convert an UTF8 StringRef to UTF8, UTF16, or UTF32 depending on 192 * WideCharWidth. The converted data is written to ResultPtr, which needs to 193 * point to at least WideCharWidth * (Source.Size() + 1) bytes. On success, 194 * ResultPtr will point one after the end of the copied string. On failure, 195 * ResultPtr will not be changed, and ErrorPtr will be set to the location of 196 * the first character which could not be converted. 197 * \return true on success. 198 */ 199 bool ConvertUTF8toWide(unsigned WideCharWidth, llvm::StringRef Source, 200 char *&ResultPtr, const UTF8 *&ErrorPtr); 201 202 /** 203 * Converts a UTF-8 StringRef to a std::wstring. 204 * \return true on success. 205 */ 206 bool ConvertUTF8toWide(llvm::StringRef Source, std::wstring &Result); 207 208 /** 209 * Converts a UTF-8 C-string to a std::wstring. 210 * \return true on success. 211 */ 212 bool ConvertUTF8toWide(const char *Source, std::wstring &Result); 213 214 /** 215 * Converts a std::wstring to a UTF-8 encoded std::string. 216 * \return true on success. 217 */ 218 bool convertWideToUTF8(const std::wstring &Source, std::string &Result); 219 220 221 /** 222 * Convert an Unicode code point to UTF8 sequence. 223 * 224 * \param Source a Unicode code point. 225 * \param [in,out] ResultPtr pointer to the output buffer, needs to be at least 226 * \c UNI_MAX_UTF8_BYTES_PER_CODE_POINT bytes. On success \c ResultPtr is 227 * updated one past end of the converted sequence. 228 * 229 * \returns true on success. 230 */ 231 bool ConvertCodePointToUTF8(unsigned Source, char *&ResultPtr); 232 233 /** 234 * Convert the first UTF8 sequence in the given source buffer to a UTF32 235 * code point. 236 * 237 * \param [in,out] source A pointer to the source buffer. If the conversion 238 * succeeds, this pointer will be updated to point to the byte just past the 239 * end of the converted sequence. 240 * \param sourceEnd A pointer just past the end of the source buffer. 241 * \param [out] target The converted code 242 * \param flags Whether the conversion is strict or lenient. 243 * 244 * \returns conversionOK on success 245 * 246 * \sa ConvertUTF8toUTF32 247 */ 248 inline ConversionResult convertUTF8Sequence(const UTF8 **source, 249 const UTF8 *sourceEnd, 250 UTF32 *target, 251 ConversionFlags flags) { 252 if (*source == sourceEnd) 253 return sourceExhausted; 254 unsigned size = getNumBytesForUTF8(**source); 255 if ((ptrdiff_t)size > sourceEnd - *source) 256 return sourceExhausted; 257 return ConvertUTF8toUTF32(source, *source + size, &target, target + 1, flags); 258 } 259 260 /** 261 * Returns true if a blob of text starts with a UTF-16 big or little endian byte 262 * order mark. 263 */ 264 bool hasUTF16ByteOrderMark(ArrayRef<char> SrcBytes); 265 266 /** 267 * Converts a stream of raw bytes assumed to be UTF16 into a UTF8 std::string. 268 * 269 * \param [in] SrcBytes A buffer of what is assumed to be UTF-16 encoded text. 270 * \param [out] Out Converted UTF-8 is stored here on success. 271 * \returns true on success 272 */ 273 bool convertUTF16ToUTF8String(ArrayRef<char> SrcBytes, std::string &Out); 274 275 /** 276 * Converts a UTF16 string into a UTF8 std::string. 277 * 278 * \param [in] Src A buffer of UTF-16 encoded text. 279 * \param [out] Out Converted UTF-8 is stored here on success. 280 * \returns true on success 281 */ 282 bool convertUTF16ToUTF8String(ArrayRef<UTF16> Src, std::string &Out); 283 284 /** 285 * Converts a UTF-8 string into a UTF-16 string with native endianness. 286 * 287 * \returns true on success 288 */ 289 bool convertUTF8ToUTF16String(StringRef SrcUTF8, 290 SmallVectorImpl<UTF16> &DstUTF16); 291 292 #if defined(_WIN32) 293 namespace sys { 294 namespace windows { 295 std::error_code UTF8ToUTF16(StringRef utf8, SmallVectorImpl<wchar_t> &utf16); 296 /// Convert to UTF16 from the current code page used in the system 297 std::error_code CurCPToUTF16(StringRef utf8, SmallVectorImpl<wchar_t> &utf16); 298 std::error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len, 299 SmallVectorImpl<char> &utf8); 300 /// Convert from UTF16 to the current code page used in the system 301 std::error_code UTF16ToCurCP(const wchar_t *utf16, size_t utf16_len, 302 SmallVectorImpl<char> &utf8); 303 } // namespace windows 304 } // namespace sys 305 #endif 306 307 } /* end namespace llvm */ 308 309 #endif 310