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The C and C++ Include Header Files
cat -n /usr/include/c++/15/text_encoding
1 // <text_encoding> -*- C++ -*- 2 3 // Copyright The GNU Toolchain Authors. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /** @file include/text_encoding 26 * This is a Standard C++ Library header. 27 */ 28 29 #ifndef _GLIBCXX_TEXT_ENCODING 30 #define _GLIBCXX_TEXT_ENCODING 31 32 #ifdef _GLIBCXX_SYSHDR 33 #pragma GCC system_header 34 #endif 35 36 #include <bits/requires_hosted.h> 37 38 #define __glibcxx_want_text_encoding 39 #include <bits/version.h> 40 41 #ifdef __cpp_lib_text_encoding 42 #include <compare> 43 #include <string_view> 44 #include <bits/functional_hash.h> // hash 45 #include <bits/ranges_util.h> // view_interface 46 #include <bits/unicode.h> // __charset_alias_match 47 #include <ext/numeric_traits.h> // __int_traits 48 49 namespace std _GLIBCXX_VISIBILITY(default) 50 { 51 _GLIBCXX_BEGIN_NAMESPACE_VERSION 52 53 /** 54 * @brief An interface for accessing the IANA Character Sets registry. 55 * @ingroup locales 56 * @since C++23 57 */ 58 struct text_encoding 59 { 60 private: 61 struct _Rep 62 { 63 using id = __INT_LEAST32_TYPE__; 64 id _M_id; 65 const char* _M_name; 66 67 friend constexpr bool 68 operator<(const _Rep& __r, id __m) noexcept 69 { return __r._M_id < __m; } 70 71 friend constexpr bool 72 operator==(const _Rep& __r, string_view __name) noexcept 73 { return __r._M_name == __name; } 74 }; 75 76 public: 77 static constexpr size_t max_name_length = 63; 78 79 enum class id : _Rep::id 80 { 81 other = 1, 82 unknown = 2, 83 ASCII = 3, 84 ISOLatin1 = 4, 85 ISOLatin2 = 5, 86 ISOLatin3 = 6, 87 ISOLatin4 = 7, 88 ISOLatinCyrillic = 8, 89 ISOLatinArabic = 9, 90 ISOLatinGreek = 10, 91 ISOLatinHebrew = 11, 92 ISOLatin5 = 12, 93 ISOLatin6 = 13, 94 ISOTextComm = 14, 95 HalfWidthKatakana = 15, 96 JISEncoding = 16, 97 ShiftJIS = 17, 98 EUCPkdFmtJapanese = 18, 99 EUCFixWidJapanese = 19, 100 ISO4UnitedKingdom = 20, 101 ISO11SwedishForNames = 21, 102 ISO15Italian = 22, 103 ISO17Spanish = 23, 104 ISO21German = 24, 105 ISO60DanishNorwegian = 25, 106 ISO69French = 26, 107 ISO10646UTF1 = 27, 108 ISO646basic1983 = 28, 109 INVARIANT = 29, 110 ISO2IntlRefVersion = 30, 111 NATSSEFI = 31, 112 NATSSEFIADD = 32, 113 ISO10Swedish = 35, 114 KSC56011987 = 36, 115 ISO2022KR = 37, 116 EUCKR = 38, 117 ISO2022JP = 39, 118 ISO2022JP2 = 40, 119 ISO13JISC6220jp = 41, 120 ISO14JISC6220ro = 42, 121 ISO16Portuguese = 43, 122 ISO18Greek7Old = 44, 123 ISO19LatinGreek = 45, 124 ISO25French = 46, 125 ISO27LatinGreek1 = 47, 126 ISO5427Cyrillic = 48, 127 ISO42JISC62261978 = 49, 128 ISO47BSViewdata = 50, 129 ISO49INIS = 51, 130 ISO50INIS8 = 52, 131 ISO51INISCyrillic = 53, 132 ISO54271981 = 54, 133 ISO5428Greek = 55, 134 ISO57GB1988 = 56, 135 ISO58GB231280 = 57, 136 ISO61Norwegian2 = 58, 137 ISO70VideotexSupp1 = 59, 138 ISO84Portuguese2 = 60, 139 ISO85Spanish2 = 61, 140 ISO86Hungarian = 62, 141 ISO87JISX0208 = 63, 142 ISO88Greek7 = 64, 143 ISO89ASMO449 = 65, 144 ISO90 = 66, 145 ISO91JISC62291984a = 67, 146 ISO92JISC62991984b = 68, 147 ISO93JIS62291984badd = 69, 148 ISO94JIS62291984hand = 70, 149 ISO95JIS62291984handadd = 71, 150 ISO96JISC62291984kana = 72, 151 ISO2033 = 73, 152 ISO99NAPLPS = 74, 153 ISO102T617bit = 75, 154 ISO103T618bit = 76, 155 ISO111ECMACyrillic = 77, 156 ISO121Canadian1 = 78, 157 ISO122Canadian2 = 79, 158 ISO123CSAZ24341985gr = 80, 159 ISO88596E = 81, 160 ISO88596I = 82, 161 ISO128T101G2 = 83, 162 ISO88598E = 84, 163 ISO88598I = 85, 164 ISO139CSN369103 = 86, 165 ISO141JUSIB1002 = 87, 166 ISO143IECP271 = 88, 167 ISO146Serbian = 89, 168 ISO147Macedonian = 90, 169 ISO150 = 91, 170 ISO151Cuba = 92, 171 ISO6937Add = 93, 172 ISO153GOST1976874 = 94, 173 ISO8859Supp = 95, 174 ISO10367Box = 96, 175 ISO158Lap = 97, 176 ISO159JISX02121990 = 98, 177 ISO646Danish = 99, 178 USDK = 100, 179 DKUS = 101, 180 KSC5636 = 102, 181 Unicode11UTF7 = 103, 182 ISO2022CN = 104, 183 ISO2022CNEXT = 105, 184 UTF8 = 106, 185 ISO885913 = 109, 186 ISO885914 = 110, 187 ISO885915 = 111, 188 ISO885916 = 112, 189 GBK = 113, 190 GB18030 = 114, 191 OSDEBCDICDF0415 = 115, 192 OSDEBCDICDF03IRV = 116, 193 OSDEBCDICDF041 = 117, 194 ISO115481 = 118, 195 KZ1048 = 119, 196 UCS2 = 1000, 197 UCS4 = 1001, 198 UnicodeASCII = 1002, 199 UnicodeLatin1 = 1003, 200 UnicodeJapanese = 1004, 201 UnicodeIBM1261 = 1005, 202 UnicodeIBM1268 = 1006, 203 UnicodeIBM1276 = 1007, 204 UnicodeIBM1264 = 1008, 205 UnicodeIBM1265 = 1009, 206 Unicode11 = 1010, 207 SCSU = 1011, 208 UTF7 = 1012, 209 UTF16BE = 1013, 210 UTF16LE = 1014, 211 UTF16 = 1015, 212 CESU8 = 1016, 213 UTF32 = 1017, 214 UTF32BE = 1018, 215 UTF32LE = 1019, 216 BOCU1 = 1020, 217 UTF7IMAP = 1021, 218 Windows30Latin1 = 2000, 219 Windows31Latin1 = 2001, 220 Windows31Latin2 = 2002, 221 Windows31Latin5 = 2003, 222 HPRoman8 = 2004, 223 AdobeStandardEncoding = 2005, 224 VenturaUS = 2006, 225 VenturaInternational = 2007, 226 DECMCS = 2008, 227 PC850Multilingual = 2009, 228 PC8DanishNorwegian = 2012, 229 PC862LatinHebrew = 2013, 230 PC8Turkish = 2014, 231 IBMSymbols = 2015, 232 IBMThai = 2016, 233 HPLegal = 2017, 234 HPPiFont = 2018, 235 HPMath8 = 2019, 236 HPPSMath = 2020, 237 HPDesktop = 2021, 238 VenturaMath = 2022, 239 MicrosoftPublishing = 2023, 240 Windows31J = 2024, 241 GB2312 = 2025, 242 Big5 = 2026, 243 Macintosh = 2027, 244 IBM037 = 2028, 245 IBM038 = 2029, 246 IBM273 = 2030, 247 IBM274 = 2031, 248 IBM275 = 2032, 249 IBM277 = 2033, 250 IBM278 = 2034, 251 IBM280 = 2035, 252 IBM281 = 2036, 253 IBM284 = 2037, 254 IBM285 = 2038, 255 IBM290 = 2039, 256 IBM297 = 2040, 257 IBM420 = 2041, 258 IBM423 = 2042, 259 IBM424 = 2043, 260 PC8CodePage437 = 2011, 261 IBM500 = 2044, 262 IBM851 = 2045, 263 PCp852 = 2010, 264 IBM855 = 2046, 265 IBM857 = 2047, 266 IBM860 = 2048, 267 IBM861 = 2049, 268 IBM863 = 2050, 269 IBM864 = 2051, 270 IBM865 = 2052, 271 IBM868 = 2053, 272 IBM869 = 2054, 273 IBM870 = 2055, 274 IBM871 = 2056, 275 IBM880 = 2057, 276 IBM891 = 2058, 277 IBM903 = 2059, 278 IBM904 = 2060, 279 IBM905 = 2061, 280 IBM918 = 2062, 281 IBM1026 = 2063, 282 IBMEBCDICATDE = 2064, 283 EBCDICATDEA = 2065, 284 EBCDICCAFR = 2066, 285 EBCDICDKNO = 2067, 286 EBCDICDKNOA = 2068, 287 EBCDICFISE = 2069, 288 EBCDICFISEA = 2070, 289 EBCDICFR = 2071, 290 EBCDICIT = 2072, 291 EBCDICPT = 2073, 292 EBCDICES = 2074, 293 EBCDICESA = 2075, 294 EBCDICESS = 2076, 295 EBCDICUK = 2077, 296 EBCDICUS = 2078, 297 Unknown8BiT = 2079, 298 Mnemonic = 2080, 299 Mnem = 2081, 300 VISCII = 2082, 301 VIQR = 2083, 302 KOI8R = 2084, 303 HZGB2312 = 2085, 304 IBM866 = 2086, 305 PC775Baltic = 2087, 306 KOI8U = 2088, 307 IBM00858 = 2089, 308 IBM00924 = 2090, 309 IBM01140 = 2091, 310 IBM01141 = 2092, 311 IBM01142 = 2093, 312 IBM01143 = 2094, 313 IBM01144 = 2095, 314 IBM01145 = 2096, 315 IBM01146 = 2097, 316 IBM01147 = 2098, 317 IBM01148 = 2099, 318 IBM01149 = 2100, 319 Big5HKSCS = 2101, 320 IBM1047 = 2102, 321 PTCP154 = 2103, 322 Amiga1251 = 2104, 323 KOI7switched = 2105, 324 BRF = 2106, 325 TSCII = 2107, 326 CP51932 = 2108, 327 windows874 = 2109, 328 windows1250 = 2250, 329 windows1251 = 2251, 330 windows1252 = 2252, 331 windows1253 = 2253, 332 windows1254 = 2254, 333 windows1255 = 2255, 334 windows1256 = 2256, 335 windows1257 = 2257, 336 windows1258 = 2258, 337 TIS620 = 2259, 338 CP50220 = 2260 339 }; 340 using enum id; 341 342 constexpr text_encoding() = default; 343 344 constexpr explicit 345 text_encoding(string_view __enc) noexcept 346 : _M_rep(_S_find_name(__enc)) 347 { 348 __enc.copy(_M_name, max_name_length); 349 } 350 351 // @pre i has the value of one of the enumerators of id. 352 constexpr 353 text_encoding(id __i) noexcept 354 : _M_rep(_S_find_id(__i)) 355 { 356 if (string_view __name(_M_rep->_M_name); !__name.empty()) 357 __name.copy(_M_name, max_name_length); 358 } 359 360 constexpr id mib() const noexcept { return id(_M_rep->_M_id); } 361 362 constexpr const char* name() const noexcept { return _M_name; } 363 364 struct aliases_view : ranges::view_interface<aliases_view> 365 { 366 private: 367 class _Iterator; 368 struct _Sentinel { }; 369 370 public: 371 constexpr _Iterator begin() const noexcept; 372 constexpr _Sentinel end() const noexcept { return {}; } 373 374 private: 375 friend struct text_encoding; 376 377 constexpr explicit aliases_view(const _Rep* __r) : _M_begin(__r) { } 378 379 const _Rep* _M_begin = nullptr; 380 }; 381 382 constexpr aliases_view 383 aliases() const noexcept 384 { 385 return _M_rep->_M_name[0] ? aliases_view(_M_rep) : aliases_view{nullptr}; 386 } 387 388 friend constexpr bool 389 operator==(const text_encoding& __a, 390 const text_encoding& __b) noexcept 391 { 392 if (__a.mib() == id::other && __b.mib() == id::other) [[unlikely]] 393 return _S_comp(__a._M_name, __b._M_name); 394 else 395 return __a.mib() == __b.mib(); 396 } 397 398 friend constexpr bool 399 operator==(const text_encoding& __encoding, id __i) noexcept 400 { return __encoding.mib() == __i; } 401 402 #if __CHAR_BIT__ == 8 403 static consteval text_encoding 404 literal() noexcept 405 { 406 #ifdef __GNUC_EXECUTION_CHARSET_NAME 407 return text_encoding(__GNUC_EXECUTION_CHARSET_NAME); 408 #elif defined __clang_literal_encoding__ 409 return text_encoding(__clang_literal_encoding__); 410 #else 411 return text_encoding(); 412 #endif 413 } 414 415 static text_encoding 416 environment(); 417 418 template<id _Id> 419 static bool 420 environment_is() 421 { return text_encoding(_Id)._M_is_environment(); } 422 #else 423 static text_encoding literal() = delete; 424 static text_encoding environment() = delete; 425 template<id> static bool environment_is() = delete; 426 #endif 427 428 private: 429 const _Rep* _M_rep = _S_reps + 1; // id::unknown 430 char _M_name[max_name_length + 1] = {0}; 431 432 bool 433 _M_is_environment() const; 434 435 static inline constexpr _Rep _S_reps[] = { 436 { 1, "" }, { 2, "" }, 437 #define _GLIBCXX_GET_ENCODING_DATA 438 #include <bits/text_encoding-data.h> 439 #ifdef _GLIBCXX_GET_ENCODING_DATA 440 # error "Invalid text_encoding data" 441 #endif 442 { 9999, nullptr }, // sentinel 443 }; 444 445 static constexpr bool 446 _S_comp(string_view __a, string_view __b) 447 { return __unicode::__charset_alias_match(__a, __b); } 448 449 static constexpr const _Rep* 450 _S_find_name(string_view __name) noexcept 451 { 452 #ifdef _GLIBCXX_TEXT_ENCODING_UTF8_OFFSET 453 // Optimize the common UTF-8 case to avoid a linear search through all 454 // strings in the table using the _S_comp function. 455 if (__name == "UTF-8") 456 return _S_reps + 2 + _GLIBCXX_TEXT_ENCODING_UTF8_OFFSET; 457 #endif 458 459 // The first two array elements (other and unknown) don't have names. 460 // The last element is a sentinel that can never match anything. 461 const auto __first = _S_reps + 2, __end = std::end(_S_reps) - 1; 462 for (auto __r = __first; __r != __end; ++__r) 463 if (_S_comp(__r->_M_name, __name)) 464 { 465 // Might have matched an alias. Find the first entry for this ID. 466 const auto __id = __r->_M_id; 467 while (__r[-1]._M_id == __id) 468 --__r; 469 return __r; 470 } 471 return _S_reps; // id::other 472 } 473 474 static constexpr const _Rep* 475 _S_find_id(id __id) noexcept 476 { 477 const auto __i = (_Rep::id)__id; 478 const auto __r = std::lower_bound(_S_reps, std::end(_S_reps) - 1, __i); 479 if (__r->_M_id == __i) [[likely]] 480 return __r; 481 else 482 { 483 // Preconditions: i has the value of one of the enumerators of id. 484 __glibcxx_assert(__r->_M_id == __i); 485 return _S_reps + 1; // id::unknown 486 } 487 } 488 }; 489 490 template<> 491 struct hash<text_encoding> 492 { 493 size_t 494 operator()(const text_encoding& __enc) const noexcept 495 { return std::hash<text_encoding::id>()(__enc.mib()); } 496 }; 497 498 class text_encoding::aliases_view::_Iterator 499 { 500 public: 501 using value_type = const char*; 502 using reference = const char*; 503 using difference_type = int; 504 505 constexpr _Iterator() = default; 506 507 constexpr value_type 508 operator*() const 509 { 510 if (_M_dereferenceable()) [[likely]] 511 return _M_rep->_M_name; 512 else 513 { 514 __glibcxx_assert(_M_dereferenceable()); 515 return ""; 516 } 517 } 518 519 constexpr _Iterator& 520 operator++() 521 { 522 if (_M_dereferenceable()) [[likely]] 523 ++_M_rep; 524 else 525 { 526 __glibcxx_assert(_M_dereferenceable()); 527 *this = _Iterator{}; 528 } 529 return *this; 530 } 531 532 constexpr _Iterator& 533 operator--() 534 { 535 const bool __decrementable 536 = _M_rep != nullptr && _M_rep[-1]._M_id == _M_id; 537 if (__decrementable) [[likely]] 538 --_M_rep; 539 else 540 { 541 __glibcxx_assert(__decrementable); 542 *this = _Iterator{}; 543 } 544 return *this; 545 } 546 547 constexpr _Iterator 548 operator++(int) 549 { 550 auto __it = *this; 551 ++*this; 552 return __it; 553 } 554 555 constexpr _Iterator 556 operator--(int) 557 { 558 auto __it = *this; 559 --*this; 560 return __it; 561 } 562 563 constexpr value_type 564 operator[](difference_type __n) const 565 { return *(*this + __n); } 566 567 constexpr _Iterator& 568 operator+=(difference_type __n) 569 { 570 if (_M_rep != nullptr) 571 { 572 if (__n > 0) 573 { 574 if (__n < (std::end(_S_reps) - _M_rep) 575 && _M_rep[__n - 1]._M_id == _M_id) [[likely]] 576 _M_rep += __n; 577 else 578 *this = _Iterator{}; 579 } 580 else if (__n < 0) 581 { 582 if (__n > (_S_reps - _M_rep) 583 && _M_rep[__n]._M_id == _M_id) [[likely]] 584 _M_rep += __n; 585 else 586 *this = _Iterator{}; 587 } 588 } 589 if (__n != 0) 590 __glibcxx_assert(_M_rep != nullptr); 591 return *this; 592 } 593 594 constexpr _Iterator& 595 operator-=(difference_type __n) 596 { 597 using _Traits = __gnu_cxx::__int_traits<difference_type>; 598 if (__n == _Traits::__min) [[unlikely]] 599 return operator+=(_Traits::__max); 600 return operator+=(-__n); 601 } 602 603 constexpr difference_type 604 operator-(const _Iterator& __i) const 605 { 606 if (_M_id == __i._M_id) 607 return _M_rep - __i._M_rep; 608 __glibcxx_assert(_M_id == __i._M_id); 609 return __gnu_cxx::__int_traits<difference_type>::__max; 610 } 611 612 constexpr bool 613 operator==(const _Iterator&) const = default; 614 615 constexpr bool 616 operator==(_Sentinel) const noexcept 617 { return !_M_dereferenceable(); } 618 619 constexpr strong_ordering 620 operator<=>(const _Iterator& __i) const 621 { 622 __glibcxx_assert(_M_id == __i._M_id); 623 return _M_rep <=> __i._M_rep; 624 } 625 626 friend constexpr _Iterator 627 operator+(_Iterator __i, difference_type __n) 628 { 629 __i += __n; 630 return __i; 631 } 632 633 friend constexpr _Iterator 634 operator+(difference_type __n, _Iterator __i) 635 { 636 __i += __n; 637 return __i; 638 } 639 640 friend constexpr _Iterator 641 operator-(_Iterator __i, difference_type __n) 642 { 643 __i -= __n; 644 return __i; 645 } 646 647 private: 648 friend struct text_encoding; 649 650 constexpr explicit 651 _Iterator(const _Rep* __r) noexcept 652 : _M_rep(__r), _M_id(__r ? __r->_M_id : 0) 653 { } 654 655 constexpr bool 656 _M_dereferenceable() const noexcept 657 { return _M_rep != nullptr && _M_rep->_M_id == _M_id; } 658 659 const _Rep* _M_rep = nullptr; 660 _Rep::id _M_id = 0; 661 }; 662 663 constexpr auto 664 text_encoding::aliases_view::begin() const noexcept 665 -> _Iterator 666 { return _Iterator(_M_begin); } 667 668 namespace ranges 669 { 670 // Opt-in to borrowed_range concept 671 template<> 672 inline constexpr bool 673 enable_borrowed_range<std::text_encoding::aliases_view> = true; 674 } 675 676 _GLIBCXX_END_NAMESPACE_VERSION 677 } // namespace std 678 679 #endif // __cpp_lib_text_encoding 680 #endif // _GLIBCXX_TEXT_ENCODING
