1// Locale support -*- C++ -*- 2 3// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 4// 2006, 2007, 2008, 2009 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 locale_classes.h 28 * This is an internal header file, included by other library headers. 29 * You should not attempt to use it directly. 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_GLIBCXX_BEGIN_NAMESPACE(std) 46 47 // 22.1.1 Class locale 48 /** 49 * @brief Container class for localization functionality. 50 * 51 * The locale class is first a class wrapper for C library locales. It is 52 * also an extensible container for user-defined localization. A locale is 53 * a collection of facets that implement various localization features such 54 * as money, time, and number printing. 55 * 56 * Constructing C++ locales does not change the C library locale. 57 * 58 * This library supports efficient construction and copying of locales 59 * through a reference counting implementation of the locale class. 60 */ 61 class locale 62 { 63 public: 64 // Types: 65 /// Definition of locale::category. 66 typedef int category; 67 68 // Forward decls and friends: 69 class facet; 70 class id; 71 class _Impl; 72 73 friend class facet; 74 friend class _Impl; 75 76 template<typename _Facet> 77 friend bool 78 has_facet(const locale&) throw(); 79 80 template<typename _Facet> 81 friend const _Facet& 82 use_facet(const locale&); 83 84 template<typename _Cache> 85 friend struct __use_cache; 86 87 //@{ 88 /** 89 * @brief Category values. 90 * 91 * The standard category values are none, ctype, numeric, collate, time, 92 * monetary, and messages. They form a bitmask that supports union and 93 * intersection. The category all is the union of these values. 94 * 95 * NB: Order must match _S_facet_categories definition in locale.cc 96 */ 97 static const category none = 0; 98 static const category ctype = 1L << 0; 99 static const category numeric = 1L << 1; 100 static const category collate = 1L << 2; 101 static const category time = 1L << 3; 102 static const category monetary = 1L << 4; 103 static const category messages = 1L << 5; 104 static const category all = (ctype | numeric | collate | 105 time | monetary | messages); 106 //@} 107 108 // Construct/copy/destroy: 109 110 /** 111 * @brief Default constructor. 112 * 113 * Constructs a copy of the global locale. If no locale has been 114 * explicitly set, this is the "C" locale. 115 */ 116 locale() throw(); 117 118 /** 119 * @brief Copy constructor. 120 * 121 * Constructs a copy of @a other. 122 * 123 * @param other The locale to copy. 124 */ 125 locale(const locale& __other) throw(); 126 127 /** 128 * @brief Named locale constructor. 129 * 130 * Constructs a copy of the named C library locale. 131 * 132 * @param s Name of the locale to construct. 133 * @throw std::runtime_error if s is null or an undefined locale. 134 */ 135 explicit 136 locale(const char* __s); 137 138 /** 139 * @brief Construct locale with facets from another locale. 140 * 141 * Constructs a copy of the locale @a base. The facets specified by @a 142 * cat are replaced with those from the locale named by @a s. If base is 143 * named, this locale instance will also be named. 144 * 145 * @param base The locale to copy. 146 * @param s Name of the locale to use facets from. 147 * @param cat Set of categories defining the facets to use from s. 148 * @throw std::runtime_error if s is null or an undefined locale. 149 */ 150 locale(const locale& __base, const char* __s, category __cat); 151 152 /** 153 * @brief Construct locale with facets from another locale. 154 * 155 * Constructs a copy of the locale @a base. The facets specified by @a 156 * cat are replaced with those from the locale @a add. If @a base and @a 157 * add are named, this locale instance will also be named. 158 * 159 * @param base The locale to copy. 160 * @param add The locale to use facets from. 161 * @param cat Set of categories defining the facets to use from add. 162 */ 163 locale(const locale& __base, const locale& __add, category __cat); 164 165 /** 166 * @brief Construct locale with another facet. 167 * 168 * Constructs a copy of the locale @a other. The facet @f is added to 169 * @other, replacing an existing facet of type Facet if there is one. If 170 * @f is null, this locale is a copy of @a other. 171 * 172 * @param other The locale to copy. 173 * @param f The facet to add in. 174 */ 175 template<typename _Facet> 176 locale(const locale& __other, _Facet* __f); 177 178 /// Locale destructor. 179 ~locale() throw(); 180 181 /** 182 * @brief Assignment operator. 183 * 184 * Set this locale to be a copy of @a other. 185 * 186 * @param other The locale to copy. 187 * @return A reference to this locale. 188 */ 189 const locale& 190 operator=(const locale& __other) throw(); 191 192 /** 193 * @brief Construct locale with another facet. 194 * 195 * Constructs and returns a new copy of this locale. Adds or replaces an 196 * existing facet of type Facet from the locale @a other into the new 197 * locale. 198 * 199 * @param Facet The facet type to copy from other 200 * @param other The locale to copy from. 201 * @return Newly constructed locale. 202 * @throw std::runtime_error if other has no facet of type Facet. 203 */ 204 template<typename _Facet> 205 locale 206 combine(const locale& __other) const; 207 208 // Locale operations: 209 /** 210 * @brief Return locale name. 211 * @return Locale name or "*" if unnamed. 212 */ 213 string 214 name() const; 215 216 /** 217 * @brief Locale equality. 218 * 219 * @param other The locale to compare against. 220 * @return True if other and this refer to the same locale instance, are 221 * copies, or have the same name. False otherwise. 222 */ 223 bool 224 operator==(const locale& __other) const throw (); 225 226 /** 227 * @brief Locale inequality. 228 * 229 * @param other The locale to compare against. 230 * @return ! (*this == other) 231 */ 232 bool 233 operator!=(const locale& __other) const throw () 234 { return !(this->operator==(__other)); } 235 236 /** 237 * @brief Compare two strings according to collate. 238 * 239 * Template operator to compare two strings using the compare function of 240 * the collate facet in this locale. One use is to provide the locale to 241 * the sort function. For example, a vector v of strings could be sorted 242 * according to locale loc by doing: 243 * @code 244 * std::sort(v.begin(), v.end(), loc); 245 * @endcode 246 * 247 * @param s1 First string to compare. 248 * @param s2 Second string to compare. 249 * @return True if collate<Char> facet compares s1 < s2, else false. 250 */ 251 template<typename _Char, typename _Traits, typename _Alloc> 252 bool 253 operator()(const basic_string<_Char, _Traits, _Alloc>& __s1, 254 const basic_string<_Char, _Traits, _Alloc>& __s2) const; 255 256 // Global locale objects: 257 /** 258 * @brief Set global locale 259 * 260 * This function sets the global locale to the argument and returns a 261 * copy of the previous global locale. If the argument has a name, it 262 * will also call std::setlocale(LC_ALL, loc.name()). 263 * 264 * @param locale The new locale to make global. 265 * @return Copy of the old global locale. 266 */ 267 static locale 268 global(const locale&); 269 270 /** 271 * @brief Return reference to the "C" locale. 272 */ 273 static const locale& 274 classic(); 275 276 private: 277 // The (shared) implementation 278 _Impl* _M_impl; 279 280 // The "C" reference locale 281 static _Impl* _S_classic; 282 283 // Current global locale 284 static _Impl* _S_global; 285 286 // Names of underlying locale categories. 287 // NB: locale::global() has to know how to modify all the 288 // underlying categories, not just the ones required by the C++ 289 // standard. 290 static const char* const* const _S_categories; 291 292 // Number of standard categories. For C++, these categories are 293 // collate, ctype, monetary, numeric, time, and messages. These 294 // directly correspond to ISO C99 macros LC_COLLATE, LC_CTYPE, 295 // LC_MONETARY, LC_NUMERIC, and LC_TIME. In addition, POSIX (IEEE 296 // 1003.1-2001) specifies LC_MESSAGES. 297 // In addition to the standard categories, the underlying 298 // operating system is allowed to define extra LC_* 299 // macros. For GNU systems, the following are also valid: 300 // LC_PAPER, LC_NAME, LC_ADDRESS, LC_TELEPHONE, LC_MEASUREMENT, 301 // and LC_IDENTIFICATION. 302 enum { _S_categories_size = 6 + _GLIBCXX_NUM_CATEGORIES }; 303 304#ifdef __GTHREADS 305 static __gthread_once_t _S_once; 306#endif 307 308 explicit 309 locale(_Impl*) throw(); 310 311 static void 312 _S_initialize(); 313 314 static void 315 _S_initialize_once(); 316 317 static category 318 _S_normalize_category(category); 319 320 void 321 _M_coalesce(const locale& __base, const locale& __add, category __cat); 322 }; 323 324 325 // 22.1.1.1.2 Class locale::facet 326 /** 327 * @brief Localization functionality base class. 328 * 329 * The facet class is the base class for a localization feature, such as 330 * money, time, and number printing. It provides common support for facets 331 * and reference management. 332 * 333 * Facets may not be copied or assigned. 334 */ 335 class locale::facet 336 { 337 private: 338 friend class locale; 339 friend class locale::_Impl; 340 341 mutable _Atomic_word _M_refcount; 342 343 // Contains data from the underlying "C" library for the classic locale. 344 static __c_locale _S_c_locale; 345 346 // String literal for the name of the classic locale. 347 static const char _S_c_name[2]; 348 349#ifdef __GTHREADS 350 static __gthread_once_t _S_once; 351#endif 352 353 static void 354 _S_initialize_once(); 355 356 protected: 357 /** 358 * @brief Facet constructor. 359 * 360 * This is the constructor provided by the standard. If refs is 0, the 361 * facet is destroyed when the last referencing locale is destroyed. 362 * Otherwise the facet will never be destroyed. 363 * 364 * @param refs The initial value for reference count. 365 */ 366 explicit 367 facet(size_t __refs = 0) throw() : _M_refcount(__refs ? 1 : 0) 368 { } 369 370 /// Facet destructor. 371 virtual 372 ~facet(); 373 374 static void 375 _S_create_c_locale(__c_locale& __cloc, const char* __s, 376 __c_locale __old = 0); 377 378 static __c_locale 379 _S_clone_c_locale(__c_locale& __cloc); 380 381 static void 382 _S_destroy_c_locale(__c_locale& __cloc); 383 384 // Returns data from the underlying "C" library data for the 385 // classic locale. 386 static __c_locale 387 _S_get_c_locale(); 388 389 static const char* 390 _S_get_c_name(); 391 392 private: 393 void 394 _M_add_reference() const throw() 395 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 396 397 void 398 _M_remove_reference() const throw() 399 { 400 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 401 { 402 __try 403 { delete this; } 404 __catch(...) 405 { } 406 } 407 } 408 409 facet(const facet&); // Not defined. 410 411 facet& 412 operator=(const facet&); // Not defined. 413 }; 414 415 416 // 22.1.1.1.3 Class locale::id 417 /** 418 * @brief Facet ID class. 419 * 420 * The ID class provides facets with an index used to identify them. 421 * Every facet class must define a public static member locale::id, or be 422 * derived from a facet that provides this member, otherwise the facet 423 * cannot be used in a locale. The locale::id ensures that each class 424 * type gets a unique identifier. 425 */ 426 class locale::id 427 { 428 private: 429 friend class locale; 430 friend class locale::_Impl; 431 432 template<typename _Facet> 433 friend const _Facet& 434 use_facet(const locale&); 435 436 template<typename _Facet> 437 friend bool 438 has_facet(const locale&) throw (); 439 440 // NB: There is no accessor for _M_index because it may be used 441 // before the constructor is run; the effect of calling a member 442 // function (even an inline) would be undefined. 443 mutable size_t _M_index; 444 445 // Last id number assigned. 446 static _Atomic_word _S_refcount; 447 448 void 449 operator=(const id&); // Not defined. 450 451 id(const id&); // Not defined. 452 453 public: 454 // NB: This class is always a static data member, and thus can be 455 // counted on to be zero-initialized. 456 /// Constructor. 457 id() { } 458 459 size_t 460 _M_id() const; 461 }; 462 463 464 // Implementation object for locale. 465 class locale::_Impl 466 { 467 public: 468 // Friends. 469 friend class locale; 470 friend class locale::facet; 471 472 template<typename _Facet> 473 friend bool 474 has_facet(const locale&) throw(); 475 476 template<typename _Facet> 477 friend const _Facet& 478 use_facet(const locale&); 479 480 template<typename _Cache> 481 friend struct __use_cache; 482 483 private: 484 // Data Members. 485 _Atomic_word _M_refcount; 486 const facet** _M_facets; 487 size_t _M_facets_size; 488 const facet** _M_caches; 489 char** _M_names; 490 static const locale::id* const _S_id_ctype[]; 491 static const locale::id* const _S_id_numeric[]; 492 static const locale::id* const _S_id_collate[]; 493 static const locale::id* const _S_id_time[]; 494 static const locale::id* const _S_id_monetary[]; 495 static const locale::id* const _S_id_messages[]; 496 static const locale::id* const* const _S_facet_categories[]; 497 498 void 499 _M_add_reference() throw() 500 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 501 502 void 503 _M_remove_reference() throw() 504 { 505 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 506 { 507 __try 508 { delete this; } 509 __catch(...) 510 { } 511 } 512 } 513 514 _Impl(const _Impl&, size_t); 515 _Impl(const char*, size_t); 516 _Impl(size_t) throw(); 517 518 ~_Impl() throw(); 519 520 _Impl(const _Impl&); // Not defined. 521 522 void 523 operator=(const _Impl&); // Not defined. 524 525 bool 526 _M_check_same_name() 527 { 528 bool __ret = true; 529 if (_M_names[1]) 530 // We must actually compare all the _M_names: can be all equal! 531 for (size_t __i = 0; __ret && __i < _S_categories_size - 1; ++__i) 532 __ret = __builtin_strcmp(_M_names[__i], _M_names[__i + 1]) == 0; 533 return __ret; 534 } 535 536 void 537 _M_replace_categories(const _Impl*, category); 538 539 void 540 _M_replace_category(const _Impl*, const locale::id* const*); 541 542 void 543 _M_replace_facet(const _Impl*, const locale::id*); 544 545 void 546 _M_install_facet(const locale::id*, const facet*); 547 548 template<typename _Facet> 549 void 550 _M_init_facet(_Facet* __facet) 551 { _M_install_facet(&_Facet::id, __facet); } 552 553 void 554 _M_install_cache(const facet*, size_t); 555 }; 556 557 558 /** 559 * @brief Test for the presence of a facet. 560 * 561 * has_facet tests the locale argument for the presence of the facet type 562 * provided as the template parameter. Facets derived from the facet 563 * parameter will also return true. 564 * 565 * @param Facet The facet type to test the presence of. 566 * @param locale The locale to test. 567 * @return true if locale contains a facet of type Facet, else false. 568 */ 569 template<typename _Facet> 570 bool 571 has_facet(const locale& __loc) throw(); 572 573 /** 574 * @brief Return a facet. 575 * 576 * use_facet looks for and returns a reference to a facet of type Facet 577 * where Facet is the template parameter. If has_facet(locale) is true, 578 * there is a suitable facet to return. It throws std::bad_cast if the 579 * locale doesn't contain a facet of type Facet. 580 * 581 * @param Facet The facet type to access. 582 * @param locale The locale to use. 583 * @return Reference to facet of type Facet. 584 * @throw std::bad_cast if locale doesn't contain a facet of type Facet. 585 */ 586 template<typename _Facet> 587 const _Facet& 588 use_facet(const locale& __loc); 589 590 591 /** 592 * @brief Facet for localized string comparison. 593 * 594 * This facet encapsulates the code to compare strings in a localized 595 * manner. 596 * 597 * The collate template uses protected virtual functions to provide 598 * the actual results. The public accessors forward the call to 599 * the virtual functions. These virtual functions are hooks for 600 * developers to implement the behavior they require from the 601 * collate facet. 602 */ 603 template<typename _CharT> 604 class collate : public locale::facet 605 { 606 public: 607 // Types: 608 //@{ 609 /// Public typedefs 610 typedef _CharT char_type; 611 typedef basic_string<_CharT> string_type; 612 //@} 613 614 protected: 615 // Underlying "C" library locale information saved from 616 // initialization, needed by collate_byname as well. 617 __c_locale _M_c_locale_collate; 618 619 public: 620 /// Numpunct facet id. 621 static locale::id id; 622 623 /** 624 * @brief Constructor performs initialization. 625 * 626 * This is the constructor provided by the standard. 627 * 628 * @param refs Passed to the base facet class. 629 */ 630 explicit 631 collate(size_t __refs = 0) 632 : facet(__refs), _M_c_locale_collate(_S_get_c_locale()) 633 { } 634 635 /** 636 * @brief Internal constructor. Not for general use. 637 * 638 * This is a constructor for use by the library itself to set up new 639 * locales. 640 * 641 * @param cloc The "C" locale. 642 * @param refs Passed to the base facet class. 643 */ 644 explicit 645 collate(__c_locale __cloc, size_t __refs = 0) 646 : facet(__refs), _M_c_locale_collate(_S_clone_c_locale(__cloc)) 647 { } 648 649 /** 650 * @brief Compare two strings. 651 * 652 * This function compares two strings and returns the result by calling 653 * collate::do_compare(). 654 * 655 * @param lo1 Start of string 1. 656 * @param hi1 End of string 1. 657 * @param lo2 Start of string 2. 658 * @param hi2 End of string 2. 659 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 660 */ 661 int 662 compare(const _CharT* __lo1, const _CharT* __hi1, 663 const _CharT* __lo2, const _CharT* __hi2) const 664 { return this->do_compare(__lo1, __hi1, __lo2, __hi2); } 665 666 /** 667 * @brief Transform string to comparable form. 668 * 669 * This function is a wrapper for strxfrm functionality. It takes the 670 * input string and returns a modified string that can be directly 671 * compared to other transformed strings. In the "C" locale, this 672 * function just returns a copy of the input string. In some other 673 * locales, it may replace two chars with one, change a char for 674 * another, etc. It does so by returning collate::do_transform(). 675 * 676 * @param lo Start of string. 677 * @param hi End of string. 678 * @return Transformed string_type. 679 */ 680 string_type 681 transform(const _CharT* __lo, const _CharT* __hi) const 682 { return this->do_transform(__lo, __hi); } 683 684 /** 685 * @brief Return hash of a string. 686 * 687 * This function computes and returns a hash on the input string. It 688 * does so by returning collate::do_hash(). 689 * 690 * @param lo Start of string. 691 * @param hi End of string. 692 * @return Hash value. 693 */ 694 long 695 hash(const _CharT* __lo, const _CharT* __hi) const 696 { return this->do_hash(__lo, __hi); } 697 698 // Used to abstract out _CharT bits in virtual member functions, below. 699 int 700 _M_compare(const _CharT*, const _CharT*) const; 701 702 size_t 703 _M_transform(_CharT*, const _CharT*, size_t) const; 704 705 protected: 706 /// Destructor. 707 virtual 708 ~collate() 709 { _S_destroy_c_locale(_M_c_locale_collate); } 710 711 /** 712 * @brief Compare two strings. 713 * 714 * This function is a hook for derived classes to change the value 715 * returned. @see compare(). 716 * 717 * @param lo1 Start of string 1. 718 * @param hi1 End of string 1. 719 * @param lo2 Start of string 2. 720 * @param hi2 End of string 2. 721 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 722 */ 723 virtual int 724 do_compare(const _CharT* __lo1, const _CharT* __hi1, 725 const _CharT* __lo2, const _CharT* __hi2) const; 726 727 /** 728 * @brief Transform string to comparable form. 729 * 730 * This function is a hook for derived classes to change the value 731 * returned. 732 * 733 * @param lo1 Start of string 1. 734 * @param hi1 End of string 1. 735 * @param lo2 Start of string 2. 736 * @param hi2 End of string 2. 737 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 738 */ 739 virtual string_type 740 do_transform(const _CharT* __lo, const _CharT* __hi) const; 741 742 /** 743 * @brief Return hash of a string. 744 * 745 * This function computes and returns a hash on the input string. This 746 * function is a hook for derived classes to change the value returned. 747 * 748 * @param lo Start of string. 749 * @param hi End of string. 750 * @return Hash value. 751 */ 752 virtual long 753 do_hash(const _CharT* __lo, const _CharT* __hi) const; 754 }; 755 756 template<typename _CharT> 757 locale::id collate<_CharT>::id; 758 759 // Specializations. 760 template<> 761 int 762 collate<char>::_M_compare(const char*, const char*) const; 763 764 template<> 765 size_t 766 collate<char>::_M_transform(char*, const char*, size_t) const; 767 768#ifdef _GLIBCXX_USE_WCHAR_T 769 template<> 770 int 771 collate<wchar_t>::_M_compare(const wchar_t*, const wchar_t*) const; 772 773 template<> 774 size_t 775 collate<wchar_t>::_M_transform(wchar_t*, const wchar_t*, size_t) const; 776#endif 777 778 /// class collate_byname [22.2.4.2]. 779 template<typename _CharT> 780 class collate_byname : public collate<_CharT> 781 { 782 public: 783 //@{ 784 /// Public typedefs 785 typedef _CharT char_type; 786 typedef basic_string<_CharT> string_type; 787 //@} 788 789 explicit 790 collate_byname(const char* __s, size_t __refs = 0) 791 : collate<_CharT>(__refs) 792 { 793 if (__builtin_strcmp(__s, "C") != 0 794 && __builtin_strcmp(__s, "POSIX") != 0) 795 { 796 this->_S_destroy_c_locale(this->_M_c_locale_collate); 797 this->_S_create_c_locale(this->_M_c_locale_collate, __s); 798 } 799 } 800 801 protected: 802 virtual 803 ~collate_byname() { } 804 }; 805 806_GLIBCXX_END_NAMESPACE 807 808#ifndef _GLIBCXX_EXPORT_TEMPLATE 809# include <bits/locale_classes.tcc> 810#endif 811 812#endif 813