1 // Locale support -*- C++ -*- 2 3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 4 // 2006, 2007, 2008, 2009, 2010, 2011 5 // Free Software Foundation, Inc. 6 // 7 // This file is part of the GNU ISO C++ Library. This library is free 8 // software; you can redistribute it and/or modify it under the 9 // terms of the GNU General Public License as published by the 10 // Free Software Foundation; either version 3, or (at your option) 11 // any later version. 12 13 // This library is distributed in the hope that it will be useful, 14 // but WITHOUT ANY WARRANTY; without even the implied warranty of 15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 // GNU General Public License for more details. 17 18 // Under Section 7 of GPL version 3, you are granted additional 19 // permissions described in the GCC Runtime Library Exception, version 20 // 3.1, as published by the Free Software Foundation. 21 22 // You should have received a copy of the GNU General Public License and 23 // a copy of the GCC Runtime Library Exception along with this program; 24 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 25 // <http://www.gnu.org/licenses/>. 26 27 /** @file bits/locale_classes.h 28 * This is an internal header file, included by other library headers. 29 * Do not attempt to use it directly. @headername{locale} 30 */ 31 32 // 33 // ISO C++ 14882: 22.1 Locales 34 // 35 36 #ifndef _LOCALE_CLASSES_H 37 #define _LOCALE_CLASSES_H 1 38 39 #pragma GCC system_header 40 41 #include <bits/localefwd.h> 42 #include <string> 43 #include <ext/atomicity.h> 44 45 namespace std _GLIBCXX_VISIBILITY(default) 46 { 47 _GLIBCXX_BEGIN_NAMESPACE_VERSION 48 49 // 22.1.1 Class locale 50 /** 51 * @brief Container class for localization functionality. 52 * @ingroup locales 53 * 54 * The locale class is first a class wrapper for C library locales. It is 55 * also an extensible container for user-defined localization. A locale is 56 * a collection of facets that implement various localization features such 57 * as money, time, and number printing. 58 * 59 * Constructing C++ locales does not change the C library locale. 60 * 61 * This library supports efficient construction and copying of locales 62 * through a reference counting implementation of the locale class. 63 */ 64 class locale 65 { 66 public: 67 // Types: 68 /// Definition of locale::category. 69 typedef int category; 70 71 // Forward decls and friends: 72 class facet; 73 class id; 74 class _Impl; 75 76 friend class facet; 77 friend class _Impl; 78 79 template<typename _Facet> 80 friend bool 81 has_facet(const locale&) throw(); 82 83 template<typename _Facet> 84 friend const _Facet& 85 use_facet(const locale&); 86 87 template<typename _Cache> 88 friend struct __use_cache; 89 90 //@{ 91 /** 92 * @brief Category values. 93 * 94 * The standard category values are none, ctype, numeric, collate, time, 95 * monetary, and messages. They form a bitmask that supports union and 96 * intersection. The category all is the union of these values. 97 * 98 * NB: Order must match _S_facet_categories definition in locale.cc 99 */ 100 static const category none = 0; 101 static const category ctype = 1L << 0; 102 static const category numeric = 1L << 1; 103 static const category collate = 1L << 2; 104 static const category time = 1L << 3; 105 static const category monetary = 1L << 4; 106 static const category messages = 1L << 5; 107 static const category all = (ctype | numeric | collate | 108 time | monetary | messages); 109 //@} 110 111 // Construct/copy/destroy: 112 113 /** 114 * @brief Default constructor. 115 * 116 * Constructs a copy of the global locale. If no locale has been 117 * explicitly set, this is the C locale. 118 */ 119 locale() throw(); 120 121 /** 122 * @brief Copy constructor. 123 * 124 * Constructs a copy of @a other. 125 * 126 * @param __other The locale to copy. 127 */ 128 locale(const locale& __other) throw(); 129 130 /** 131 * @brief Named locale constructor. 132 * 133 * Constructs a copy of the named C library locale. 134 * 135 * @param __s Name of the locale to construct. 136 * @throw std::runtime_error if __s is null or an undefined locale. 137 */ 138 explicit 139 locale(const char* __s); 140 141 /** 142 * @brief Construct locale with facets from another locale. 143 * 144 * Constructs a copy of the locale @a base. The facets specified by @a 145 * cat are replaced with those from the locale named by @a s. If base is 146 * named, this locale instance will also be named. 147 * 148 * @param __base The locale to copy. 149 * @param __s Name of the locale to use facets from. 150 * @param __cat Set of categories defining the facets to use from __s. 151 * @throw std::runtime_error if __s is null or an undefined locale. 152 */ 153 locale(const locale& __base, const char* __s, category __cat); 154 155 /** 156 * @brief Construct locale with facets from another locale. 157 * 158 * Constructs a copy of the locale @a base. The facets specified by @a 159 * cat are replaced with those from the locale @a add. If @a base and @a 160 * add are named, this locale instance will also be named. 161 * 162 * @param __base The locale to copy. 163 * @param __add The locale to use facets from. 164 * @param __cat Set of categories defining the facets to use from add. 165 */ 166 locale(const locale& __base, const locale& __add, category __cat); 167 168 /** 169 * @brief Construct locale with another facet. 170 * 171 * Constructs a copy of the locale @a __other. The facet @a __f 172 * is added to @a __other, replacing an existing facet of type 173 * Facet if there is one. If @a __f is null, this locale is a 174 * copy of @a __other. 175 * 176 * @param __other The locale to copy. 177 * @param __f The facet to add in. 178 */ 179 template<typename _Facet> 180 locale(const locale& __other, _Facet* __f); 181 182 /// Locale destructor. 183 ~locale() throw(); 184 185 /** 186 * @brief Assignment operator. 187 * 188 * Set this locale to be a copy of @a other. 189 * 190 * @param __other The locale to copy. 191 * @return A reference to this locale. 192 */ 193 const locale& 194 operator=(const locale& __other) throw(); 195 196 /** 197 * @brief Construct locale with another facet. 198 * 199 * Constructs and returns a new copy of this locale. Adds or replaces an 200 * existing facet of type Facet from the locale @a other into the new 201 * locale. 202 * 203 * @tparam _Facet The facet type to copy from other 204 * @param __other The locale to copy from. 205 * @return Newly constructed locale. 206 * @throw std::runtime_error if __other has no facet of type _Facet. 207 */ 208 template<typename _Facet> 209 locale 210 combine(const locale& __other) const; 211 212 // Locale operations: 213 /** 214 * @brief Return locale name. 215 * @return Locale name or "*" if unnamed. 216 */ 217 string 218 name() const; 219 220 /** 221 * @brief Locale equality. 222 * 223 * @param __other The locale to compare against. 224 * @return True if other and this refer to the same locale instance, are 225 * copies, or have the same name. False otherwise. 226 */ 227 bool 228 operator==(const locale& __other) const throw(); 229 230 /** 231 * @brief Locale inequality. 232 * 233 * @param __other The locale to compare against. 234 * @return ! (*this == __other) 235 */ 236 bool 237 operator!=(const locale& __other) const throw() 238 { return !(this->operator==(__other)); } 239 240 /** 241 * @brief Compare two strings according to collate. 242 * 243 * Template operator to compare two strings using the compare function of 244 * the collate facet in this locale. One use is to provide the locale to 245 * the sort function. For example, a vector v of strings could be sorted 246 * according to locale loc by doing: 247 * @code 248 * std::sort(v.begin(), v.end(), loc); 249 * @endcode 250 * 251 * @param __s1 First string to compare. 252 * @param __s2 Second string to compare. 253 * @return True if collate<_Char> facet compares __s1 < __s2, else false. 254 */ 255 template<typename _Char, typename _Traits, typename _Alloc> 256 bool 257 operator()(const basic_string<_Char, _Traits, _Alloc>& __s1, 258 const basic_string<_Char, _Traits, _Alloc>& __s2) const; 259 260 // Global locale objects: 261 /** 262 * @brief Set global locale 263 * 264 * This function sets the global locale to the argument and returns a 265 * copy of the previous global locale. If the argument has a name, it 266 * will also call std::setlocale(LC_ALL, loc.name()). 267 * 268 * @param __loc The new locale to make global. 269 * @return Copy of the old global locale. 270 */ 271 static locale 272 global(const locale& __loc); 273 274 /** 275 * @brief Return reference to the C locale. 276 */ 277 static const locale& 278 classic(); 279 280 private: 281 // The (shared) implementation 282 _Impl* _M_impl; 283 284 // The "C" reference locale 285 static _Impl* _S_classic; 286 287 // Current global locale 288 static _Impl* _S_global; 289 290 // Names of underlying locale categories. 291 // NB: locale::global() has to know how to modify all the 292 // underlying categories, not just the ones required by the C++ 293 // standard. 294 static const char* const* const _S_categories; 295 296 // Number of standard categories. For C++, these categories are 297 // collate, ctype, monetary, numeric, time, and messages. These 298 // directly correspond to ISO C99 macros LC_COLLATE, LC_CTYPE, 299 // LC_MONETARY, LC_NUMERIC, and LC_TIME. In addition, POSIX (IEEE 300 // 1003.1-2001) specifies LC_MESSAGES. 301 // In addition to the standard categories, the underlying 302 // operating system is allowed to define extra LC_* 303 // macros. For GNU systems, the following are also valid: 304 // LC_PAPER, LC_NAME, LC_ADDRESS, LC_TELEPHONE, LC_MEASUREMENT, 305 // and LC_IDENTIFICATION. 306 enum { _S_categories_size = 6 + _GLIBCXX_NUM_CATEGORIES }; 307 308 #ifdef __GTHREADS 309 static __gthread_once_t _S_once; 310 #endif 311 312 explicit 313 locale(_Impl*) throw(); 314 315 static void 316 _S_initialize(); 317 318 static void 319 _S_initialize_once() throw(); 320 321 static category 322 _S_normalize_category(category); 323 324 void 325 _M_coalesce(const locale& __base, const locale& __add, category __cat); 326 }; 327 328 329 // 22.1.1.1.2 Class locale::facet 330 /** 331 * @brief Localization functionality base class. 332 * @ingroup locales 333 * 334 * The facet class is the base class for a localization feature, such as 335 * money, time, and number printing. It provides common support for facets 336 * and reference management. 337 * 338 * Facets may not be copied or assigned. 339 */ 340 class locale::facet 341 { 342 private: 343 friend class locale; 344 friend class locale::_Impl; 345 346 mutable _Atomic_word _M_refcount; 347 348 // Contains data from the underlying "C" library for the classic locale. 349 static __c_locale _S_c_locale; 350 351 // String literal for the name of the classic locale. 352 static const char _S_c_name[2]; 353 354 #ifdef __GTHREADS 355 static __gthread_once_t _S_once; 356 #endif 357 358 static void 359 _S_initialize_once(); 360 361 protected: 362 /** 363 * @brief Facet constructor. 364 * 365 * This is the constructor provided by the standard. If refs is 0, the 366 * facet is destroyed when the last referencing locale is destroyed. 367 * Otherwise the facet will never be destroyed. 368 * 369 * @param __refs The initial value for reference count. 370 */ 371 explicit 372 facet(size_t __refs = 0) throw() : _M_refcount(__refs ? 1 : 0) 373 { } 374 375 /// Facet destructor. 376 virtual 377 ~facet(); 378 379 static void 380 _S_create_c_locale(__c_locale& __cloc, const char* __s, 381 __c_locale __old = 0); 382 383 static __c_locale 384 _S_clone_c_locale(__c_locale& __cloc) throw(); 385 386 static void 387 _S_destroy_c_locale(__c_locale& __cloc); 388 389 static __c_locale 390 _S_lc_ctype_c_locale(__c_locale __cloc, const char* __s); 391 392 // Returns data from the underlying "C" library data for the 393 // classic locale. 394 static __c_locale 395 _S_get_c_locale(); 396 397 _GLIBCXX_CONST static const char* 398 _S_get_c_name() throw(); 399 400 private: 401 void 402 _M_add_reference() const throw() 403 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 404 405 void 406 _M_remove_reference() const throw() 407 { 408 // Be race-detector-friendly. For more info see bits/c++config. 409 _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount); 410 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 411 { 412 _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount); 413 __try 414 { delete this; } 415 __catch(...) 416 { } 417 } 418 } 419 420 facet(const facet&); // Not defined. 421 422 facet& 423 operator=(const facet&); // Not defined. 424 }; 425 426 427 // 22.1.1.1.3 Class locale::id 428 /** 429 * @brief Facet ID class. 430 * @ingroup locales 431 * 432 * The ID class provides facets with an index used to identify them. 433 * Every facet class must define a public static member locale::id, or be 434 * derived from a facet that provides this member, otherwise the facet 435 * cannot be used in a locale. The locale::id ensures that each class 436 * type gets a unique identifier. 437 */ 438 class locale::id 439 { 440 private: 441 friend class locale; 442 friend class locale::_Impl; 443 444 template<typename _Facet> 445 friend const _Facet& 446 use_facet(const locale&); 447 448 template<typename _Facet> 449 friend bool 450 has_facet(const locale&) throw(); 451 452 // NB: There is no accessor for _M_index because it may be used 453 // before the constructor is run; the effect of calling a member 454 // function (even an inline) would be undefined. 455 mutable size_t _M_index; 456 457 // Last id number assigned. 458 static _Atomic_word _S_refcount; 459 460 void 461 operator=(const id&); // Not defined. 462 463 id(const id&); // Not defined. 464 465 public: 466 // NB: This class is always a static data member, and thus can be 467 // counted on to be zero-initialized. 468 /// Constructor. 469 id() { } 470 471 size_t 472 _M_id() const throw(); 473 }; 474 475 476 // Implementation object for locale. 477 class locale::_Impl 478 { 479 public: 480 // Friends. 481 friend class locale; 482 friend class locale::facet; 483 484 template<typename _Facet> 485 friend bool 486 has_facet(const locale&) throw(); 487 488 template<typename _Facet> 489 friend const _Facet& 490 use_facet(const locale&); 491 492 template<typename _Cache> 493 friend struct __use_cache; 494 495 private: 496 // Data Members. 497 _Atomic_word _M_refcount; 498 const facet** _M_facets; 499 size_t _M_facets_size; 500 const facet** _M_caches; 501 char** _M_names; 502 static const locale::id* const _S_id_ctype[]; 503 static const locale::id* const _S_id_numeric[]; 504 static const locale::id* const _S_id_collate[]; 505 static const locale::id* const _S_id_time[]; 506 static const locale::id* const _S_id_monetary[]; 507 static const locale::id* const _S_id_messages[]; 508 static const locale::id* const* const _S_facet_categories[]; 509 510 void 511 _M_add_reference() throw() 512 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 513 514 void 515 _M_remove_reference() throw() 516 { 517 // Be race-detector-friendly. For more info see bits/c++config. 518 _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount); 519 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 520 { 521 _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount); 522 __try 523 { delete this; } 524 __catch(...) 525 { } 526 } 527 } 528 529 _Impl(const _Impl&, size_t); 530 _Impl(const char*, size_t); 531 _Impl(size_t) throw(); 532 533 ~_Impl() throw(); 534 535 _Impl(const _Impl&); // Not defined. 536 537 void 538 operator=(const _Impl&); // Not defined. 539 540 bool 541 _M_check_same_name() 542 { 543 bool __ret = true; 544 if (_M_names[1]) 545 // We must actually compare all the _M_names: can be all equal! 546 for (size_t __i = 0; __ret && __i < _S_categories_size - 1; ++__i) 547 __ret = __builtin_strcmp(_M_names[__i], _M_names[__i + 1]) == 0; 548 return __ret; 549 } 550 551 void 552 _M_replace_categories(const _Impl*, category); 553 554 void 555 _M_replace_category(const _Impl*, const locale::id* const*); 556 557 void 558 _M_replace_facet(const _Impl*, const locale::id*); 559 560 void 561 _M_install_facet(const locale::id*, const facet*); 562 563 template<typename _Facet> 564 void 565 _M_init_facet(_Facet* __facet) 566 { _M_install_facet(&_Facet::id, __facet); } 567 568 void 569 _M_install_cache(const facet*, size_t); 570 }; 571 572 573 /** 574 * @brief Facet for localized string comparison. 575 * 576 * This facet encapsulates the code to compare strings in a localized 577 * manner. 578 * 579 * The collate template uses protected virtual functions to provide 580 * the actual results. The public accessors forward the call to 581 * the virtual functions. These virtual functions are hooks for 582 * developers to implement the behavior they require from the 583 * collate facet. 584 */ 585 template<typename _CharT> 586 class collate : public locale::facet 587 { 588 public: 589 // Types: 590 //@{ 591 /// Public typedefs 592 typedef _CharT char_type; 593 typedef basic_string<_CharT> string_type; 594 //@} 595 596 protected: 597 // Underlying "C" library locale information saved from 598 // initialization, needed by collate_byname as well. 599 __c_locale _M_c_locale_collate; 600 601 public: 602 /// Numpunct facet id. 603 static locale::id id; 604 605 /** 606 * @brief Constructor performs initialization. 607 * 608 * This is the constructor provided by the standard. 609 * 610 * @param __refs Passed to the base facet class. 611 */ 612 explicit 613 collate(size_t __refs = 0) 614 : facet(__refs), _M_c_locale_collate(_S_get_c_locale()) 615 { } 616 617 /** 618 * @brief Internal constructor. Not for general use. 619 * 620 * This is a constructor for use by the library itself to set up new 621 * locales. 622 * 623 * @param __cloc The C locale. 624 * @param __refs Passed to the base facet class. 625 */ 626 explicit 627 collate(__c_locale __cloc, size_t __refs = 0) 628 : facet(__refs), _M_c_locale_collate(_S_clone_c_locale(__cloc)) 629 { } 630 631 /** 632 * @brief Compare two strings. 633 * 634 * This function compares two strings and returns the result by calling 635 * collate::do_compare(). 636 * 637 * @param __lo1 Start of string 1. 638 * @param __hi1 End of string 1. 639 * @param __lo2 Start of string 2. 640 * @param __hi2 End of string 2. 641 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 642 */ 643 int 644 compare(const _CharT* __lo1, const _CharT* __hi1, 645 const _CharT* __lo2, const _CharT* __hi2) const 646 { return this->do_compare(__lo1, __hi1, __lo2, __hi2); } 647 648 /** 649 * @brief Transform string to comparable form. 650 * 651 * This function is a wrapper for strxfrm functionality. It takes the 652 * input string and returns a modified string that can be directly 653 * compared to other transformed strings. In the C locale, this 654 * function just returns a copy of the input string. In some other 655 * locales, it may replace two chars with one, change a char for 656 * another, etc. It does so by returning collate::do_transform(). 657 * 658 * @param __lo Start of string. 659 * @param __hi End of string. 660 * @return Transformed string_type. 661 */ 662 string_type 663 transform(const _CharT* __lo, const _CharT* __hi) const 664 { return this->do_transform(__lo, __hi); } 665 666 /** 667 * @brief Return hash of a string. 668 * 669 * This function computes and returns a hash on the input string. It 670 * does so by returning collate::do_hash(). 671 * 672 * @param __lo Start of string. 673 * @param __hi End of string. 674 * @return Hash value. 675 */ 676 long 677 hash(const _CharT* __lo, const _CharT* __hi) const 678 { return this->do_hash(__lo, __hi); } 679 680 // Used to abstract out _CharT bits in virtual member functions, below. 681 int 682 _M_compare(const _CharT*, const _CharT*) const throw(); 683 684 size_t 685 _M_transform(_CharT*, const _CharT*, size_t) const throw(); 686 687 protected: 688 /// Destructor. 689 virtual 690 ~collate() 691 { _S_destroy_c_locale(_M_c_locale_collate); } 692 693 /** 694 * @brief Compare two strings. 695 * 696 * This function is a hook for derived classes to change the value 697 * returned. @see compare(). 698 * 699 * @param __lo1 Start of string 1. 700 * @param __hi1 End of string 1. 701 * @param __lo2 Start of string 2. 702 * @param __hi2 End of string 2. 703 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 704 */ 705 virtual int 706 do_compare(const _CharT* __lo1, const _CharT* __hi1, 707 const _CharT* __lo2, const _CharT* __hi2) const; 708 709 /** 710 * @brief Transform string to comparable form. 711 * 712 * This function is a hook for derived classes to change the value 713 * returned. 714 * 715 * @param __lo Start. 716 * @param __hi End. 717 * @return transformed string. 718 */ 719 virtual string_type 720 do_transform(const _CharT* __lo, const _CharT* __hi) const; 721 722 /** 723 * @brief Return hash of a string. 724 * 725 * This function computes and returns a hash on the input string. This 726 * function is a hook for derived classes to change the value returned. 727 * 728 * @param __lo Start of string. 729 * @param __hi End of string. 730 * @return Hash value. 731 */ 732 virtual long 733 do_hash(const _CharT* __lo, const _CharT* __hi) const; 734 }; 735 736 template<typename _CharT> 737 locale::id collate<_CharT>::id; 738 739 // Specializations. 740 template<> 741 int 742 collate<char>::_M_compare(const char*, const char*) const throw(); 743 744 template<> 745 size_t 746 collate<char>::_M_transform(char*, const char*, size_t) const throw(); 747 748 #ifdef _GLIBCXX_USE_WCHAR_T 749 template<> 750 int 751 collate<wchar_t>::_M_compare(const wchar_t*, const wchar_t*) const throw(); 752 753 template<> 754 size_t 755 collate<wchar_t>::_M_transform(wchar_t*, const wchar_t*, size_t) const throw(); 756 #endif 757 758 /// class collate_byname [22.2.4.2]. 759 template<typename _CharT> 760 class collate_byname : public collate<_CharT> 761 { 762 public: 763 //@{ 764 /// Public typedefs 765 typedef _CharT char_type; 766 typedef basic_string<_CharT> string_type; 767 //@} 768 769 explicit 770 collate_byname(const char* __s, size_t __refs = 0) 771 : collate<_CharT>(__refs) 772 { 773 if (__builtin_strcmp(__s, "C") != 0 774 && __builtin_strcmp(__s, "POSIX") != 0) 775 { 776 this->_S_destroy_c_locale(this->_M_c_locale_collate); 777 this->_S_create_c_locale(this->_M_c_locale_collate, __s); 778 } 779 } 780 781 protected: 782 virtual 783 ~collate_byname() { } 784 }; 785 786 _GLIBCXX_END_NAMESPACE_VERSION 787 } // namespace 788 789 # include <bits/locale_classes.tcc> 790 791 #endif 792
