1 // Locale support -*- C++ -*- 2 3 // Copyright (C) 1997-2013 Free Software Foundation, Inc. 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 bits/locale_classes.h 26 * This is an internal header file, included by other library headers. 27 * Do not attempt to use it directly. @headername{locale} 28 */ 29 30 // 31 // ISO C++ 14882: 22.1 Locales 32 // 33 34 #ifndef _LOCALE_CLASSES_H 35 #define _LOCALE_CLASSES_H 1 36 37 #pragma GCC system_header 38 39 #include <bits/localefwd.h> 40 #include <string> 41 #include <ext/atomicity.h> 42 43 namespace std _GLIBCXX_VISIBILITY(default) 44 { 45 _GLIBCXX_BEGIN_NAMESPACE_VERSION 46 47 // 22.1.1 Class locale 48 /** 49 * @brief Container class for localization functionality. 50 * @ingroup locales 51 * 52 * The locale class is first a class wrapper for C library locales. It is 53 * also an extensible container for user-defined localization. A locale is 54 * a collection of facets that implement various localization features such 55 * as money, time, and number printing. 56 * 57 * Constructing C++ locales does not change the C library locale. 58 * 59 * This library supports efficient construction and copying of locales 60 * through a reference counting implementation of the locale class. 61 */ 62 class locale 63 { 64 public: 65 // Types: 66 /// Definition of locale::category. 67 typedef int category; 68 69 // Forward decls and friends: 70 class facet; 71 class id; 72 class _Impl; 73 74 friend class facet; 75 friend class _Impl; 76 77 template<typename _Facet> 78 friend bool 79 has_facet(const locale&) throw(); 80 81 template<typename _Facet> 82 friend const _Facet& 83 use_facet(const locale&); 84 85 template<typename _Cache> 86 friend struct __use_cache; 87 88 //@{ 89 /** 90 * @brief Category values. 91 * 92 * The standard category values are none, ctype, numeric, collate, time, 93 * monetary, and messages. They form a bitmask that supports union and 94 * intersection. The category all is the union of these values. 95 * 96 * NB: Order must match _S_facet_categories definition in locale.cc 97 */ 98 static const category none = 0; 99 static const category ctype = 1L << 0; 100 static const category numeric = 1L << 1; 101 static const category collate = 1L << 2; 102 static const category time = 1L << 3; 103 static const category monetary = 1L << 4; 104 static const category messages = 1L << 5; 105 static const category all = (ctype | numeric | collate | 106 time | monetary | messages); 107 //@} 108 109 // Construct/copy/destroy: 110 111 /** 112 * @brief Default constructor. 113 * 114 * Constructs a copy of the global locale. If no locale has been 115 * explicitly set, this is the C locale. 116 */ 117 locale() throw(); 118 119 /** 120 * @brief Copy constructor. 121 * 122 * Constructs a copy of @a other. 123 * 124 * @param __other The locale to copy. 125 */ 126 locale(const locale& __other) throw(); 127 128 /** 129 * @brief Named locale constructor. 130 * 131 * Constructs a copy of the named C library locale. 132 * 133 * @param __s Name of the locale to construct. 134 * @throw std::runtime_error if __s is null or an undefined locale. 135 */ 136 explicit 137 locale(const char* __s); 138 139 /** 140 * @brief Construct locale with facets from another locale. 141 * 142 * Constructs a copy of the locale @a base. The facets specified by @a 143 * cat are replaced with those from the locale named by @a s. If base is 144 * named, this locale instance will also be named. 145 * 146 * @param __base The locale to copy. 147 * @param __s Name of the locale to use facets from. 148 * @param __cat Set of categories defining the facets to use from __s. 149 * @throw std::runtime_error if __s is null or an undefined locale. 150 */ 151 locale(const locale& __base, const char* __s, category __cat); 152 153 /** 154 * @brief Construct locale with facets from another locale. 155 * 156 * Constructs a copy of the locale @a base. The facets specified by @a 157 * cat are replaced with those from the locale @a add. If @a base and @a 158 * add are named, this locale instance will also be named. 159 * 160 * @param __base The locale to copy. 161 * @param __add The locale to use facets from. 162 * @param __cat Set of categories defining the facets to use from add. 163 */ 164 locale(const locale& __base, const locale& __add, category __cat); 165 166 /** 167 * @brief Construct locale with another facet. 168 * 169 * Constructs a copy of the locale @a __other. The facet @a __f 170 * is added to @a __other, replacing an existing facet of type 171 * Facet if there is one. If @a __f is null, this locale is a 172 * copy of @a __other. 173 * 174 * @param __other The locale to copy. 175 * @param __f The facet to add in. 176 */ 177 template<typename _Facet> 178 locale(const locale& __other, _Facet* __f); 179 180 /// Locale destructor. 181 ~locale() throw(); 182 183 /** 184 * @brief Assignment operator. 185 * 186 * Set this locale to be a copy of @a other. 187 * 188 * @param __other The locale to copy. 189 * @return A reference to this locale. 190 */ 191 const locale& 192 operator=(const locale& __other) throw(); 193 194 /** 195 * @brief Construct locale with another facet. 196 * 197 * Constructs and returns a new copy of this locale. Adds or replaces an 198 * existing facet of type Facet from the locale @a other into the new 199 * locale. 200 * 201 * @tparam _Facet The facet type to copy from other 202 * @param __other The locale to copy from. 203 * @return Newly constructed locale. 204 * @throw std::runtime_error if __other has no facet of type _Facet. 205 */ 206 template<typename _Facet> 207 locale 208 combine(const locale& __other) const; 209 210 // Locale operations: 211 /** 212 * @brief Return locale name. 213 * @return Locale name or "*" if unnamed. 214 */ 215 string 216 name() const; 217 218 /** 219 * @brief Locale equality. 220 * 221 * @param __other The locale to compare against. 222 * @return True if other and this refer to the same locale instance, are 223 * copies, or have the same name. False otherwise. 224 */ 225 bool 226 operator==(const locale& __other) const throw(); 227 228 /** 229 * @brief Locale inequality. 230 * 231 * @param __other The locale to compare against. 232 * @return ! (*this == __other) 233 */ 234 bool 235 operator!=(const locale& __other) const throw() 236 { return !(this->operator==(__other)); } 237 238 /** 239 * @brief Compare two strings according to collate. 240 * 241 * Template operator to compare two strings using the compare function of 242 * the collate facet in this locale. One use is to provide the locale to 243 * the sort function. For example, a vector v of strings could be sorted 244 * according to locale loc by doing: 245 * @code 246 * std::sort(v.begin(), v.end(), loc); 247 * @endcode 248 * 249 * @param __s1 First string to compare. 250 * @param __s2 Second string to compare. 251 * @return True if collate<_Char> facet compares __s1 < __s2, else false. 252 */ 253 template<typename _Char, typename _Traits, typename _Alloc> 254 bool 255 operator()(const basic_string<_Char, _Traits, _Alloc>& __s1, 256 const basic_string<_Char, _Traits, _Alloc>& __s2) const; 257 258 // Global locale objects: 259 /** 260 * @brief Set global locale 261 * 262 * This function sets the global locale to the argument and returns a 263 * copy of the previous global locale. If the argument has a name, it 264 * will also call std::setlocale(LC_ALL, loc.name()). 265 * 266 * @param __loc The new locale to make global. 267 * @return Copy of the old global locale. 268 */ 269 static locale 270 global(const locale& __loc); 271 272 /** 273 * @brief Return reference to the C locale. 274 */ 275 static const locale& 276 classic(); 277 278 private: 279 // The (shared) implementation 280 _Impl* _M_impl; 281 282 // The "C" reference locale 283 static _Impl* _S_classic; 284 285 // Current global locale 286 static _Impl* _S_global; 287 288 // Names of underlying locale categories. 289 // NB: locale::global() has to know how to modify all the 290 // underlying categories, not just the ones required by the C++ 291 // standard. 292 static const char* const* const _S_categories; 293 294 // Number of standard categories. For C++, these categories are 295 // collate, ctype, monetary, numeric, time, and messages. These 296 // directly correspond to ISO C99 macros LC_COLLATE, LC_CTYPE, 297 // LC_MONETARY, LC_NUMERIC, and LC_TIME. In addition, POSIX (IEEE 298 // 1003.1-2001) specifies LC_MESSAGES. 299 // In addition to the standard categories, the underlying 300 // operating system is allowed to define extra LC_* 301 // macros. For GNU systems, the following are also valid: 302 // LC_PAPER, LC_NAME, LC_ADDRESS, LC_TELEPHONE, LC_MEASUREMENT, 303 // and LC_IDENTIFICATION. 304 enum { _S_categories_size = 6 + _GLIBCXX_NUM_CATEGORIES }; 305 306 #ifdef __GTHREADS 307 static __gthread_once_t _S_once; 308 #endif 309 310 explicit 311 locale(_Impl*) throw(); 312 313 static void 314 _S_initialize(); 315 316 static void 317 _S_initialize_once() throw(); 318 319 static category 320 _S_normalize_category(category); 321 322 void 323 _M_coalesce(const locale& __base, const locale& __add, category __cat); 324 }; 325 326 327 // 22.1.1.1.2 Class locale::facet 328 /** 329 * @brief Localization functionality base class. 330 * @ingroup locales 331 * 332 * The facet class is the base class for a localization feature, such as 333 * money, time, and number printing. It provides common support for facets 334 * and reference management. 335 * 336 * Facets may not be copied or assigned. 337 */ 338 class locale::facet 339 { 340 private: 341 friend class locale; 342 friend class locale::_Impl; 343 344 mutable _Atomic_word _M_refcount; 345 346 // Contains data from the underlying "C" library for the classic locale. 347 static __c_locale _S_c_locale; 348 349 // String literal for the name of the classic locale. 350 static const char _S_c_name[2]; 351 352 #ifdef __GTHREADS 353 static __gthread_once_t _S_once; 354 #endif 355 356 static void 357 _S_initialize_once(); 358 359 protected: 360 /** 361 * @brief Facet constructor. 362 * 363 * This is the constructor provided by the standard. If refs is 0, the 364 * facet is destroyed when the last referencing locale is destroyed. 365 * Otherwise the facet will never be destroyed. 366 * 367 * @param __refs The initial value for reference count. 368 */ 369 explicit 370 facet(size_t __refs = 0) throw() : _M_refcount(__refs ? 1 : 0) 371 { } 372 373 /// Facet destructor. 374 virtual 375 ~facet(); 376 377 static void 378 _S_create_c_locale(__c_locale& __cloc, const char* __s, 379 __c_locale __old = 0); 380 381 static __c_locale 382 _S_clone_c_locale(__c_locale& __cloc) throw(); 383 384 static void 385 _S_destroy_c_locale(__c_locale& __cloc); 386 387 static __c_locale 388 _S_lc_ctype_c_locale(__c_locale __cloc, const char* __s); 389 390 // Returns data from the underlying "C" library data for the 391 // classic locale. 392 static __c_locale 393 _S_get_c_locale(); 394 395 _GLIBCXX_CONST static const char* 396 _S_get_c_name() throw(); 397 398 private: 399 void 400 _M_add_reference() const throw() 401 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 402 403 void 404 _M_remove_reference() const throw() 405 { 406 // Be race-detector-friendly. For more info see bits/c++config. 407 _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount); 408 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 409 { 410 _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount); 411 __try 412 { delete this; } 413 __catch(...) 414 { } 415 } 416 } 417 418 facet(const facet&); // Not defined. 419 420 facet& 421 operator=(const facet&); // Not defined. 422 }; 423 424 425 // 22.1.1.1.3 Class locale::id 426 /** 427 * @brief Facet ID class. 428 * @ingroup locales 429 * 430 * The ID class provides facets with an index used to identify them. 431 * Every facet class must define a public static member locale::id, or be 432 * derived from a facet that provides this member, otherwise the facet 433 * cannot be used in a locale. The locale::id ensures that each class 434 * type gets a unique identifier. 435 */ 436 class locale::id 437 { 438 private: 439 friend class locale; 440 friend class locale::_Impl; 441 442 template<typename _Facet> 443 friend const _Facet& 444 use_facet(const locale&); 445 446 template<typename _Facet> 447 friend bool 448 has_facet(const locale&) throw(); 449 450 // NB: There is no accessor for _M_index because it may be used 451 // before the constructor is run; the effect of calling a member 452 // function (even an inline) would be undefined. 453 mutable size_t _M_index; 454 455 // Last id number assigned. 456 static _Atomic_word _S_refcount; 457 458 void 459 operator=(const id&); // Not defined. 460 461 id(const id&); // Not defined. 462 463 public: 464 // NB: This class is always a static data member, and thus can be 465 // counted on to be zero-initialized. 466 /// Constructor. 467 id() { } 468 469 size_t 470 _M_id() const throw(); 471 }; 472 473 474 // Implementation object for locale. 475 class locale::_Impl 476 { 477 public: 478 // Friends. 479 friend class locale; 480 friend class locale::facet; 481 482 template<typename _Facet> 483 friend bool 484 has_facet(const locale&) throw(); 485 486 template<typename _Facet> 487 friend const _Facet& 488 use_facet(const locale&); 489 490 template<typename _Cache> 491 friend struct __use_cache; 492 493 private: 494 // Data Members. 495 _Atomic_word _M_refcount; 496 const facet** _M_facets; 497 size_t _M_facets_size; 498 const facet** _M_caches; 499 char** _M_names; 500 static const locale::id* const _S_id_ctype[]; 501 static const locale::id* const _S_id_numeric[]; 502 static const locale::id* const _S_id_collate[]; 503 static const locale::id* const _S_id_time[]; 504 static const locale::id* const _S_id_monetary[]; 505 static const locale::id* const _S_id_messages[]; 506 static const locale::id* const* const _S_facet_categories[]; 507 508 void 509 _M_add_reference() throw() 510 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 511 512 void 513 _M_remove_reference() throw() 514 { 515 // Be race-detector-friendly. For more info see bits/c++config. 516 _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount); 517 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 518 { 519 _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount); 520 __try 521 { delete this; } 522 __catch(...) 523 { } 524 } 525 } 526 527 _Impl(const _Impl&, size_t); 528 _Impl(const char*, size_t); 529 _Impl(size_t) throw(); 530 531 ~_Impl() throw(); 532 533 _Impl(const _Impl&); // Not defined. 534 535 void 536 operator=(const _Impl&); // Not defined. 537 538 bool 539 _M_check_same_name() 540 { 541 bool __ret = true; 542 if (_M_names[1]) 543 // We must actually compare all the _M_names: can be all equal! 544 for (size_t __i = 0; __ret && __i < _S_categories_size - 1; ++__i) 545 __ret = __builtin_strcmp(_M_names[__i], _M_names[__i + 1]) == 0; 546 return __ret; 547 } 548 549 void 550 _M_replace_categories(const _Impl*, category); 551 552 void 553 _M_replace_category(const _Impl*, const locale::id* const*); 554 555 void 556 _M_replace_facet(const _Impl*, const locale::id*); 557 558 void 559 _M_install_facet(const locale::id*, const facet*); 560 561 template<typename _Facet> 562 void 563 _M_init_facet(_Facet* __facet) 564 { _M_install_facet(&_Facet::id, __facet); } 565 566 void 567 _M_install_cache(const facet*, size_t); 568 }; 569 570 571 /** 572 * @brief Facet for localized string comparison. 573 * 574 * This facet encapsulates the code to compare strings in a localized 575 * manner. 576 * 577 * The collate template uses protected virtual functions to provide 578 * the actual results. The public accessors forward the call to 579 * the virtual functions. These virtual functions are hooks for 580 * developers to implement the behavior they require from the 581 * collate facet. 582 */ 583 template<typename _CharT> 584 class collate : public locale::facet 585 { 586 public: 587 // Types: 588 //@{ 589 /// Public typedefs 590 typedef _CharT char_type; 591 typedef basic_string<_CharT> string_type; 592 //@} 593 594 protected: 595 // Underlying "C" library locale information saved from 596 // initialization, needed by collate_byname as well. 597 __c_locale _M_c_locale_collate; 598 599 public: 600 /// Numpunct facet id. 601 static locale::id id; 602 603 /** 604 * @brief Constructor performs initialization. 605 * 606 * This is the constructor provided by the standard. 607 * 608 * @param __refs Passed to the base facet class. 609 */ 610 explicit 611 collate(size_t __refs = 0) 612 : facet(__refs), _M_c_locale_collate(_S_get_c_locale()) 613 { } 614 615 /** 616 * @brief Internal constructor. Not for general use. 617 * 618 * This is a constructor for use by the library itself to set up new 619 * locales. 620 * 621 * @param __cloc The C locale. 622 * @param __refs Passed to the base facet class. 623 */ 624 explicit 625 collate(__c_locale __cloc, size_t __refs = 0) 626 : facet(__refs), _M_c_locale_collate(_S_clone_c_locale(__cloc)) 627 { } 628 629 /** 630 * @brief Compare two strings. 631 * 632 * This function compares two strings and returns the result by calling 633 * collate::do_compare(). 634 * 635 * @param __lo1 Start of string 1. 636 * @param __hi1 End of string 1. 637 * @param __lo2 Start of string 2. 638 * @param __hi2 End of string 2. 639 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 640 */ 641 int 642 compare(const _CharT* __lo1, const _CharT* __hi1, 643 const _CharT* __lo2, const _CharT* __hi2) const 644 { return this->do_compare(__lo1, __hi1, __lo2, __hi2); } 645 646 /** 647 * @brief Transform string to comparable form. 648 * 649 * This function is a wrapper for strxfrm functionality. It takes the 650 * input string and returns a modified string that can be directly 651 * compared to other transformed strings. In the C locale, this 652 * function just returns a copy of the input string. In some other 653 * locales, it may replace two chars with one, change a char for 654 * another, etc. It does so by returning collate::do_transform(). 655 * 656 * @param __lo Start of string. 657 * @param __hi End of string. 658 * @return Transformed string_type. 659 */ 660 string_type 661 transform(const _CharT* __lo, const _CharT* __hi) const 662 { return this->do_transform(__lo, __hi); } 663 664 /** 665 * @brief Return hash of a string. 666 * 667 * This function computes and returns a hash on the input string. It 668 * does so by returning collate::do_hash(). 669 * 670 * @param __lo Start of string. 671 * @param __hi End of string. 672 * @return Hash value. 673 */ 674 long 675 hash(const _CharT* __lo, const _CharT* __hi) const 676 { return this->do_hash(__lo, __hi); } 677 678 // Used to abstract out _CharT bits in virtual member functions, below. 679 int 680 _M_compare(const _CharT*, const _CharT*) const throw(); 681 682 size_t 683 _M_transform(_CharT*, const _CharT*, size_t) const throw(); 684 685 protected: 686 /// Destructor. 687 virtual 688 ~collate() 689 { _S_destroy_c_locale(_M_c_locale_collate); } 690 691 /** 692 * @brief Compare two strings. 693 * 694 * This function is a hook for derived classes to change the value 695 * returned. @see compare(). 696 * 697 * @param __lo1 Start of string 1. 698 * @param __hi1 End of string 1. 699 * @param __lo2 Start of string 2. 700 * @param __hi2 End of string 2. 701 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 702 */ 703 virtual int 704 do_compare(const _CharT* __lo1, const _CharT* __hi1, 705 const _CharT* __lo2, const _CharT* __hi2) const; 706 707 /** 708 * @brief Transform string to comparable form. 709 * 710 * This function is a hook for derived classes to change the value 711 * returned. 712 * 713 * @param __lo Start. 714 * @param __hi End. 715 * @return transformed string. 716 */ 717 virtual string_type 718 do_transform(const _CharT* __lo, const _CharT* __hi) const; 719 720 /** 721 * @brief Return hash of a string. 722 * 723 * This function computes and returns a hash on the input string. This 724 * function is a hook for derived classes to change the value returned. 725 * 726 * @param __lo Start of string. 727 * @param __hi End of string. 728 * @return Hash value. 729 */ 730 virtual long 731 do_hash(const _CharT* __lo, const _CharT* __hi) const; 732 }; 733 734 template<typename _CharT> 735 locale::id collate<_CharT>::id; 736 737 // Specializations. 738 template<> 739 int 740 collate<char>::_M_compare(const char*, const char*) const throw(); 741 742 template<> 743 size_t 744 collate<char>::_M_transform(char*, const char*, size_t) const throw(); 745 746 #ifdef _GLIBCXX_USE_WCHAR_T 747 template<> 748 int 749 collate<wchar_t>::_M_compare(const wchar_t*, const wchar_t*) const throw(); 750 751 template<> 752 size_t 753 collate<wchar_t>::_M_transform(wchar_t*, const wchar_t*, size_t) const throw(); 754 #endif 755 756 /// class collate_byname [22.2.4.2]. 757 template<typename _CharT> 758 class collate_byname : public collate<_CharT> 759 { 760 public: 761 //@{ 762 /// Public typedefs 763 typedef _CharT char_type; 764 typedef basic_string<_CharT> string_type; 765 //@} 766 767 explicit 768 collate_byname(const char* __s, size_t __refs = 0) 769 : collate<_CharT>(__refs) 770 { 771 if (__builtin_strcmp(__s, "C") != 0 772 && __builtin_strcmp(__s, "POSIX") != 0) 773 { 774 this->_S_destroy_c_locale(this->_M_c_locale_collate); 775 this->_S_create_c_locale(this->_M_c_locale_collate, __s); 776 } 777 } 778 779 protected: 780 virtual 781 ~collate_byname() { } 782 }; 783 784 _GLIBCXX_END_NAMESPACE_VERSION 785 } // namespace 786 787 # include <bits/locale_classes.tcc> 788 789 #endif 790
