1// Locale support -*- C++ -*- 2 3// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 4// 2006, 2007, 2008, 2009, 2010 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 * @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 @f is added to 170 * @other, replacing an existing facet of type Facet if there is one. If 171 * @f is null, this locale is a copy of @a other. 172 * 173 * @param other The locale to copy. 174 * @param f The facet to add in. 175 */ 176 template<typename _Facet> 177 locale(const locale& __other, _Facet* __f); 178 179 /// Locale destructor. 180 ~locale() throw(); 181 182 /** 183 * @brief Assignment operator. 184 * 185 * Set this locale to be a copy of @a other. 186 * 187 * @param other The locale to copy. 188 * @return A reference to this locale. 189 */ 190 const locale& 191 operator=(const locale& __other) throw(); 192 193 /** 194 * @brief Construct locale with another facet. 195 * 196 * Constructs and returns a new copy of this locale. Adds or replaces an 197 * existing facet of type Facet from the locale @a other into the new 198 * locale. 199 * 200 * @param Facet The facet type to copy from other 201 * @param other The locale to copy from. 202 * @return Newly constructed locale. 203 * @throw std::runtime_error if other has no facet of type Facet. 204 */ 205 template<typename _Facet> 206 locale 207 combine(const locale& __other) const; 208 209 // Locale operations: 210 /** 211 * @brief Return locale name. 212 * @return Locale name or "*" if unnamed. 213 */ 214 string 215 name() const; 216 217 /** 218 * @brief Locale equality. 219 * 220 * @param other The locale to compare against. 221 * @return True if other and this refer to the same locale instance, are 222 * copies, or have the same name. False otherwise. 223 */ 224 bool 225 operator==(const locale& __other) const throw(); 226 227 /** 228 * @brief Locale inequality. 229 * 230 * @param other The locale to compare against. 231 * @return ! (*this == other) 232 */ 233 bool 234 operator!=(const locale& __other) const throw() 235 { return !(this->operator==(__other)); } 236 237 /** 238 * @brief Compare two strings according to collate. 239 * 240 * Template operator to compare two strings using the compare function of 241 * the collate facet in this locale. One use is to provide the locale to 242 * the sort function. For example, a vector v of strings could be sorted 243 * according to locale loc by doing: 244 * @code 245 * std::sort(v.begin(), v.end(), loc); 246 * @endcode 247 * 248 * @param s1 First string to compare. 249 * @param s2 Second string to compare. 250 * @return True if collate<Char> facet compares s1 < s2, else false. 251 */ 252 template<typename _Char, typename _Traits, typename _Alloc> 253 bool 254 operator()(const basic_string<_Char, _Traits, _Alloc>& __s1, 255 const basic_string<_Char, _Traits, _Alloc>& __s2) const; 256 257 // Global locale objects: 258 /** 259 * @brief Set global locale 260 * 261 * This function sets the global locale to the argument and returns a 262 * copy of the previous global locale. If the argument has a name, it 263 * will also call std::setlocale(LC_ALL, loc.name()). 264 * 265 * @param locale The new locale to make global. 266 * @return Copy of the old global locale. 267 */ 268 static locale 269 global(const locale&); 270 271 /** 272 * @brief Return reference to the C locale. 273 */ 274 static const locale& 275 classic(); 276 277 private: 278 // The (shared) implementation 279 _Impl* _M_impl; 280 281 // The "C" reference locale 282 static _Impl* _S_classic; 283 284 // Current global locale 285 static _Impl* _S_global; 286 287 // Names of underlying locale categories. 288 // NB: locale::global() has to know how to modify all the 289 // underlying categories, not just the ones required by the C++ 290 // standard. 291 static const char* const* const _S_categories; 292 293 // Number of standard categories. For C++, these categories are 294 // collate, ctype, monetary, numeric, time, and messages. These 295 // directly correspond to ISO C99 macros LC_COLLATE, LC_CTYPE, 296 // LC_MONETARY, LC_NUMERIC, and LC_TIME. In addition, POSIX (IEEE 297 // 1003.1-2001) specifies LC_MESSAGES. 298 // In addition to the standard categories, the underlying 299 // operating system is allowed to define extra LC_* 300 // macros. For GNU systems, the following are also valid: 301 // LC_PAPER, LC_NAME, LC_ADDRESS, LC_TELEPHONE, LC_MEASUREMENT, 302 // and LC_IDENTIFICATION. 303 enum { _S_categories_size = 6 + _GLIBCXX_NUM_CATEGORIES }; 304 305#ifdef __GTHREADS 306 static __gthread_once_t _S_once; 307#endif 308 309 explicit 310 locale(_Impl*) throw(); 311 312 static void 313 _S_initialize(); 314 315 static void 316 _S_initialize_once() throw(); 317 318 static category 319 _S_normalize_category(category); 320 321 void 322 _M_coalesce(const locale& __base, const locale& __add, category __cat); 323 }; 324 325 326 // 22.1.1.1.2 Class locale::facet 327 /** 328 * @brief Localization functionality base class. 329 * @ingroup locales 330 * 331 * The facet class is the base class for a localization feature, such as 332 * money, time, and number printing. It provides common support for facets 333 * and reference management. 334 * 335 * Facets may not be copied or assigned. 336 */ 337 class locale::facet 338 { 339 private: 340 friend class locale; 341 friend class locale::_Impl; 342 343 mutable _Atomic_word _M_refcount; 344 345 // Contains data from the underlying "C" library for the classic locale. 346 static __c_locale _S_c_locale; 347 348 // String literal for the name of the classic locale. 349 static const char _S_c_name[2]; 350 351#ifdef __GTHREADS 352 static __gthread_once_t _S_once; 353#endif 354 355 static void 356 _S_initialize_once(); 357 358 protected: 359 /** 360 * @brief Facet constructor. 361 * 362 * This is the constructor provided by the standard. If refs is 0, the 363 * facet is destroyed when the last referencing locale is destroyed. 364 * Otherwise the facet will never be destroyed. 365 * 366 * @param refs The initial value for reference count. 367 */ 368 explicit 369 facet(size_t __refs = 0) throw() : _M_refcount(__refs ? 1 : 0) 370 { } 371 372 /// Facet destructor. 373 virtual 374 ~facet(); 375 376 static void 377 _S_create_c_locale(__c_locale& __cloc, const char* __s, 378 __c_locale __old = 0); 379 380 static __c_locale 381 _S_clone_c_locale(__c_locale& __cloc) throw(); 382 383 static void 384 _S_destroy_c_locale(__c_locale& __cloc); 385 386 static __c_locale 387 _S_lc_ctype_c_locale(__c_locale __cloc, const char* __s); 388 389 // Returns data from the underlying "C" library data for the 390 // classic locale. 391 static __c_locale 392 _S_get_c_locale(); 393 394 _GLIBCXX_CONST static const char* 395 _S_get_c_name() throw(); 396 397 private: 398 void 399 _M_add_reference() const throw() 400 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 401 402 void 403 _M_remove_reference() const throw() 404 { 405 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 406 { 407 __try 408 { delete this; } 409 __catch(...) 410 { } 411 } 412 } 413 414 facet(const facet&); // Not defined. 415 416 facet& 417 operator=(const facet&); // Not defined. 418 }; 419 420 421 // 22.1.1.1.3 Class locale::id 422 /** 423 * @brief Facet ID class. 424 * @ingroup locales 425 * 426 * The ID class provides facets with an index used to identify them. 427 * Every facet class must define a public static member locale::id, or be 428 * derived from a facet that provides this member, otherwise the facet 429 * cannot be used in a locale. The locale::id ensures that each class 430 * type gets a unique identifier. 431 */ 432 class locale::id 433 { 434 private: 435 friend class locale; 436 friend class locale::_Impl; 437 438 template<typename _Facet> 439 friend const _Facet& 440 use_facet(const locale&); 441 442 template<typename _Facet> 443 friend bool 444 has_facet(const locale&) throw(); 445 446 // NB: There is no accessor for _M_index because it may be used 447 // before the constructor is run; the effect of calling a member 448 // function (even an inline) would be undefined. 449 mutable size_t _M_index; 450 451 // Last id number assigned. 452 static _Atomic_word _S_refcount; 453 454 void 455 operator=(const id&); // Not defined. 456 457 id(const id&); // Not defined. 458 459 public: 460 // NB: This class is always a static data member, and thus can be 461 // counted on to be zero-initialized. 462 /// Constructor. 463 id() { } 464 465 size_t 466 _M_id() const throw(); 467 }; 468 469 470 // Implementation object for locale. 471 class locale::_Impl 472 { 473 public: 474 // Friends. 475 friend class locale; 476 friend class locale::facet; 477 478 template<typename _Facet> 479 friend bool 480 has_facet(const locale&) throw(); 481 482 template<typename _Facet> 483 friend const _Facet& 484 use_facet(const locale&); 485 486 template<typename _Cache> 487 friend struct __use_cache; 488 489 private: 490 // Data Members. 491 _Atomic_word _M_refcount; 492 const facet** _M_facets; 493 size_t _M_facets_size; 494 const facet** _M_caches; 495 char** _M_names; 496 static const locale::id* const _S_id_ctype[]; 497 static const locale::id* const _S_id_numeric[]; 498 static const locale::id* const _S_id_collate[]; 499 static const locale::id* const _S_id_time[]; 500 static const locale::id* const _S_id_monetary[]; 501 static const locale::id* const _S_id_messages[]; 502 static const locale::id* const* const _S_facet_categories[]; 503 504 void 505 _M_add_reference() throw() 506 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 507 508 void 509 _M_remove_reference() throw() 510 { 511 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 512 { 513 __try 514 { delete this; } 515 __catch(...) 516 { } 517 } 518 } 519 520 _Impl(const _Impl&, size_t); 521 _Impl(const char*, size_t); 522 _Impl(size_t) throw(); 523 524 ~_Impl() throw(); 525 526 _Impl(const _Impl&); // Not defined. 527 528 void 529 operator=(const _Impl&); // Not defined. 530 531 bool 532 _M_check_same_name() 533 { 534 bool __ret = true; 535 if (_M_names[1]) 536 // We must actually compare all the _M_names: can be all equal! 537 for (size_t __i = 0; __ret && __i < _S_categories_size - 1; ++__i) 538 __ret = __builtin_strcmp(_M_names[__i], _M_names[__i + 1]) == 0; 539 return __ret; 540 } 541 542 void 543 _M_replace_categories(const _Impl*, category); 544 545 void 546 _M_replace_category(const _Impl*, const locale::id* const*); 547 548 void 549 _M_replace_facet(const _Impl*, const locale::id*); 550 551 void 552 _M_install_facet(const locale::id*, const facet*); 553 554 template<typename _Facet> 555 void 556 _M_init_facet(_Facet* __facet) 557 { _M_install_facet(&_Facet::id, __facet); } 558 559 void 560 _M_install_cache(const facet*, size_t); 561 }; 562 563 564 /** 565 * @brief Test for the presence of a facet. 566 * 567 * has_facet tests the locale argument for the presence of the facet type 568 * provided as the template parameter. Facets derived from the facet 569 * parameter will also return true. 570 * 571 * @param Facet The facet type to test the presence of. 572 * @param locale The locale to test. 573 * @return true if locale contains a facet of type Facet, else false. 574 */ 575 template<typename _Facet> 576 bool 577 has_facet(const locale& __loc) throw(); 578 579 /** 580 * @brief Return a facet. 581 * 582 * use_facet looks for and returns a reference to a facet of type Facet 583 * where Facet is the template parameter. If has_facet(locale) is true, 584 * there is a suitable facet to return. It throws std::bad_cast if the 585 * locale doesn't contain a facet of type Facet. 586 * 587 * @param Facet The facet type to access. 588 * @param locale The locale to use. 589 * @return Reference to facet of type Facet. 590 * @throw std::bad_cast if locale doesn't contain a facet of type Facet. 591 */ 592 template<typename _Facet> 593 const _Facet& 594 use_facet(const locale& __loc); 595 596 597 /** 598 * @brief Facet for localized string comparison. 599 * 600 * This facet encapsulates the code to compare strings in a localized 601 * manner. 602 * 603 * The collate template uses protected virtual functions to provide 604 * the actual results. The public accessors forward the call to 605 * the virtual functions. These virtual functions are hooks for 606 * developers to implement the behavior they require from the 607 * collate facet. 608 */ 609 template<typename _CharT> 610 class collate : public locale::facet 611 { 612 public: 613 // Types: 614 //@{ 615 /// Public typedefs 616 typedef _CharT char_type; 617 typedef basic_string<_CharT> string_type; 618 //@} 619 620 protected: 621 // Underlying "C" library locale information saved from 622 // initialization, needed by collate_byname as well. 623 __c_locale _M_c_locale_collate; 624 625 public: 626 /// Numpunct facet id. 627 static locale::id id; 628 629 /** 630 * @brief Constructor performs initialization. 631 * 632 * This is the constructor provided by the standard. 633 * 634 * @param refs Passed to the base facet class. 635 */ 636 explicit 637 collate(size_t __refs = 0) 638 : facet(__refs), _M_c_locale_collate(_S_get_c_locale()) 639 { } 640 641 /** 642 * @brief Internal constructor. Not for general use. 643 * 644 * This is a constructor for use by the library itself to set up new 645 * locales. 646 * 647 * @param cloc The C locale. 648 * @param refs Passed to the base facet class. 649 */ 650 explicit 651 collate(__c_locale __cloc, size_t __refs = 0) 652 : facet(__refs), _M_c_locale_collate(_S_clone_c_locale(__cloc)) 653 { } 654 655 /** 656 * @brief Compare two strings. 657 * 658 * This function compares two strings and returns the result by calling 659 * collate::do_compare(). 660 * 661 * @param lo1 Start of string 1. 662 * @param hi1 End of string 1. 663 * @param lo2 Start of string 2. 664 * @param hi2 End of string 2. 665 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 666 */ 667 int 668 compare(const _CharT* __lo1, const _CharT* __hi1, 669 const _CharT* __lo2, const _CharT* __hi2) const 670 { return this->do_compare(__lo1, __hi1, __lo2, __hi2); } 671 672 /** 673 * @brief Transform string to comparable form. 674 * 675 * This function is a wrapper for strxfrm functionality. It takes the 676 * input string and returns a modified string that can be directly 677 * compared to other transformed strings. In the C locale, this 678 * function just returns a copy of the input string. In some other 679 * locales, it may replace two chars with one, change a char for 680 * another, etc. It does so by returning collate::do_transform(). 681 * 682 * @param lo Start of string. 683 * @param hi End of string. 684 * @return Transformed string_type. 685 */ 686 string_type 687 transform(const _CharT* __lo, const _CharT* __hi) const 688 { return this->do_transform(__lo, __hi); } 689 690 /** 691 * @brief Return hash of a string. 692 * 693 * This function computes and returns a hash on the input string. It 694 * does so by returning collate::do_hash(). 695 * 696 * @param lo Start of string. 697 * @param hi End of string. 698 * @return Hash value. 699 */ 700 long 701 hash(const _CharT* __lo, const _CharT* __hi) const 702 { return this->do_hash(__lo, __hi); } 703 704 // Used to abstract out _CharT bits in virtual member functions, below. 705 int 706 _M_compare(const _CharT*, const _CharT*) const throw(); 707 708 size_t 709 _M_transform(_CharT*, const _CharT*, size_t) const throw(); 710 711 protected: 712 /// Destructor. 713 virtual 714 ~collate() 715 { _S_destroy_c_locale(_M_c_locale_collate); } 716 717 /** 718 * @brief Compare two strings. 719 * 720 * This function is a hook for derived classes to change the value 721 * returned. @see compare(). 722 * 723 * @param lo1 Start of string 1. 724 * @param hi1 End of string 1. 725 * @param lo2 Start of string 2. 726 * @param hi2 End of string 2. 727 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 728 */ 729 virtual int 730 do_compare(const _CharT* __lo1, const _CharT* __hi1, 731 const _CharT* __lo2, const _CharT* __hi2) const; 732 733 /** 734 * @brief Transform string to comparable form. 735 * 736 * This function is a hook for derived classes to change the value 737 * returned. 738 * 739 * @param lo1 Start of string 1. 740 * @param hi1 End of string 1. 741 * @param lo2 Start of string 2. 742 * @param hi2 End of string 2. 743 * @return 1 if string1 > string2, -1 if string1 < string2, else 0. 744 */ 745 virtual string_type 746 do_transform(const _CharT* __lo, const _CharT* __hi) const; 747 748 /** 749 * @brief Return hash of a string. 750 * 751 * This function computes and returns a hash on the input string. This 752 * function is a hook for derived classes to change the value returned. 753 * 754 * @param lo Start of string. 755 * @param hi End of string. 756 * @return Hash value. 757 */ 758 virtual long 759 do_hash(const _CharT* __lo, const _CharT* __hi) const; 760 }; 761 762 template<typename _CharT> 763 locale::id collate<_CharT>::id; 764 765 // Specializations. 766 template<> 767 int 768 collate<char>::_M_compare(const char*, const char*) const throw(); 769 770 template<> 771 size_t 772 collate<char>::_M_transform(char*, const char*, size_t) const throw(); 773 774#ifdef _GLIBCXX_USE_WCHAR_T 775 template<> 776 int 777 collate<wchar_t>::_M_compare(const wchar_t*, const wchar_t*) const throw(); 778 779 template<> 780 size_t 781 collate<wchar_t>::_M_transform(wchar_t*, const wchar_t*, size_t) const throw(); 782#endif 783 784 /// class collate_byname [22.2.4.2]. 785 template<typename _CharT> 786 class collate_byname : public collate<_CharT> 787 { 788 public: 789 //@{ 790 /// Public typedefs 791 typedef _CharT char_type; 792 typedef basic_string<_CharT> string_type; 793 //@} 794 795 explicit 796 collate_byname(const char* __s, size_t __refs = 0) 797 : collate<_CharT>(__refs) 798 { 799 if (__builtin_strcmp(__s, "C") != 0 800 && __builtin_strcmp(__s, "POSIX") != 0) 801 { 802 this->_S_destroy_c_locale(this->_M_c_locale_collate); 803 this->_S_create_c_locale(this->_M_c_locale_collate, __s); 804 } 805 } 806 807 protected: 808 virtual 809 ~collate_byname() { } 810 }; 811 812_GLIBCXX_END_NAMESPACE 813 814#ifndef _GLIBCXX_EXPORT_TEMPLATE 815# include <bits/locale_classes.tcc> 816#endif 817 818#endif 819