1// Locale support -*- C++ -*- 2 3// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 4// Free Software Foundation, Inc. 5// 6// This file is part of the GNU ISO C++ Library. This library is free 7// software; you can redistribute it and/or modify it under the 8// terms of the GNU General Public License as published by the 9// Free Software Foundation; either version 2, or (at your option) 10// any later version. 11 12// This library is distributed in the hope that it will be useful, 13// but WITHOUT ANY WARRANTY; without even the implied warranty of 14// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15// GNU General Public License for more details. 16 17// You should have received a copy of the GNU General Public License along 18// with this library; see the file COPYING. If not, write to the Free 19// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 20// USA. 21 22// As a special exception, you may use this file as part of a free software 23// library without restriction. Specifically, if other files instantiate 24// templates or use macros or inline functions from this file, or you compile 25// this file and link it with other files to produce an executable, this 26// file does not by itself cause the resulting executable to be covered by 27// the GNU General Public License. This exception does not however 28// invalidate any other reasons why the executable file might be covered by 29// the GNU General Public License. 30 31/** @file locale_classes.h 32 * This is an internal header file, included by other library headers. 33 * You should not attempt to use it directly. 34 */ 35 36// 37// ISO C++ 14882: 22.1 Locales 38// 39 40#ifndef _LOCALE_CLASSES_H 41#define _LOCALE_CLASSES_H 1 42 43#pragma GCC system_header 44 45#include <bits/localefwd.h> 46#include <cstring> // For strcmp. 47#include <string> 48#include <ext/atomicity.h> 49 50_GLIBCXX_BEGIN_NAMESPACE(std) 51 52 // 22.1.1 Class locale 53 /** 54 * @brief Container class for localization functionality. 55 * 56 * The locale class is first a class wrapper for C library locales. It is 57 * also an extensible container for user-defined localization. A locale is 58 * a collection of facets that implement various localization features such 59 * as money, time, and number printing. 60 * 61 * Constructing C++ locales does not change the C library locale. 62 * 63 * This library supports efficient construction and copying of locales 64 * through a reference counting implementation of the locale class. 65 */ 66 class locale 67 { 68 public: 69 // Types: 70 /// Definition of locale::category. 71 typedef int category; 72 73 // Forward decls and friends: 74 class facet; 75 class id; 76 class _Impl; 77 78 friend class facet; 79 friend class _Impl; 80 81 template<typename _Facet> 82 friend bool 83 has_facet(const locale&) throw(); 84 85 template<typename _Facet> 86 friend const _Facet& 87 use_facet(const locale&); 88 89 template<typename _Cache> 90 friend struct __use_cache; 91 92 //@{ 93 /** 94 * @brief Category values. 95 * 96 * The standard category values are none, ctype, numeric, collate, time, 97 * monetary, and messages. They form a bitmask that supports union and 98 * intersection. The category all is the union of these values. 99 * 100 * @if maint 101 * NB: Order must match _S_facet_categories definition in locale.cc 102 * @endif 103 */ 104 static const category none = 0; 105 static const category ctype = 1L << 0; 106 static const category numeric = 1L << 1; 107 static const category collate = 1L << 2; 108 static const category time = 1L << 3; 109 static const category monetary = 1L << 4; 110 static const category messages = 1L << 5; 111 static const category all = (ctype | numeric | collate | 112 time | monetary | messages); 113 //@} 114 115 // Construct/copy/destroy: 116 117 /** 118 * @brief Default constructor. 119 * 120 * Constructs a copy of the global locale. If no locale has been 121 * explicitly set, this is the "C" locale. 122 */ 123 locale() throw(); 124 125 /** 126 * @brief Copy constructor. 127 * 128 * Constructs a copy of @a other. 129 * 130 * @param other The locale to copy. 131 */ 132 locale(const locale& __other) throw(); 133 134 /** 135 * @brief Named locale constructor. 136 * 137 * Constructs a copy of the named C library locale. 138 * 139 * @param s Name of the locale to construct. 140 * @throw std::runtime_error if s is null or an undefined locale. 141 */ 142 explicit 143 locale(const char* __s); 144 145 /** 146 * @brief Construct locale with facets from another locale. 147 * 148 * Constructs a copy of the locale @a base. The facets specified by @a 149 * cat are replaced with those from the locale named by @a s. If base is 150 * named, this locale instance will also be named. 151 * 152 * @param base The locale to copy. 153 * @param s Name of the locale to use facets from. 154 * @param cat Set of categories defining the facets to use from s. 155 * @throw std::runtime_error if s is null or an undefined locale. 156 */ 157 locale(const locale& __base, const char* __s, category __cat); 158 159 /** 160 * @brief Construct locale with facets from another locale. 161 * 162 * Constructs a copy of the locale @a base. The facets specified by @a 163 * cat are replaced with those from the locale @a add. If @a base and @a 164 * add are named, this locale instance will also be named. 165 * 166 * @param base The locale to copy. 167 * @param add The locale to use facets from. 168 * @param cat Set of categories defining the facets to use from add. 169 */ 170 locale(const locale& __base, const locale& __add, category __cat); 171 172 /** 173 * @brief Construct locale with another facet. 174 * 175 * Constructs a copy of the locale @a other. The facet @f is added to 176 * @other, replacing an existing facet of type Facet if there is one. If 177 * @f is null, this locale is a copy of @a other. 178 * 179 * @param other The locale to copy. 180 * @param f The facet to add in. 181 */ 182 template<typename _Facet> 183 locale(const locale& __other, _Facet* __f); 184 185 /// Locale destructor. 186 ~locale() throw(); 187 188 /** 189 * @brief Assignment operator. 190 * 191 * Set this locale to be a copy of @a other. 192 * 193 * @param other The locale to copy. 194 * @return A reference to this locale. 195 */ 196 const locale& 197 operator=(const locale& __other) throw(); 198 199 /** 200 * @brief Construct locale with another facet. 201 * 202 * Constructs and returns a new copy of this locale. Adds or replaces an 203 * existing facet of type Facet from the locale @a other into the new 204 * locale. 205 * 206 * @param Facet The facet type to copy from other 207 * @param other The locale to copy from. 208 * @return Newly constructed locale. 209 * @throw std::runtime_error if other has no facet of type Facet. 210 */ 211 template<typename _Facet> 212 locale 213 combine(const locale& __other) const; 214 215 // Locale operations: 216 /** 217 * @brief Return locale name. 218 * @return Locale name or "*" if unnamed. 219 */ 220 string 221 name() const; 222 223 /** 224 * @brief Locale equality. 225 * 226 * @param other The locale to compare against. 227 * @return True if other and this refer to the same locale instance, are 228 * copies, or have the same name. False otherwise. 229 */ 230 bool 231 operator==(const locale& __other) const throw (); 232 233 /** 234 * @brief Locale inequality. 235 * 236 * @param other The locale to compare against. 237 * @return ! (*this == other) 238 */ 239 inline bool 240 operator!=(const locale& __other) const throw () 241 { return !(this->operator==(__other)); } 242 243 /** 244 * @brief Compare two strings according to collate. 245 * 246 * Template operator to compare two strings using the compare function of 247 * the collate facet in this locale. One use is to provide the locale to 248 * the sort function. For example, a vector v of strings could be sorted 249 * according to locale loc by doing: 250 * @code 251 * std::sort(v.begin(), v.end(), loc); 252 * @endcode 253 * 254 * @param s1 First string to compare. 255 * @param s2 Second string to compare. 256 * @return True if collate<Char> facet compares s1 < s2, else false. 257 */ 258 template<typename _Char, typename _Traits, typename _Alloc> 259 bool 260 operator()(const basic_string<_Char, _Traits, _Alloc>& __s1, 261 const basic_string<_Char, _Traits, _Alloc>& __s2) const; 262 263 // Global locale objects: 264 /** 265 * @brief Set global locale 266 * 267 * This function sets the global locale to the argument and returns a 268 * copy of the previous global locale. If the argument has a name, it 269 * will also call std::setlocale(LC_ALL, loc.name()). 270 * 271 * @param locale The new locale to make global. 272 * @return Copy of the old global locale. 273 */ 274 static locale 275 global(const locale&); 276 277 /** 278 * @brief Return reference to the "C" locale. 279 */ 280 static const locale& 281 classic(); 282 283 private: 284 // The (shared) implementation 285 _Impl* _M_impl; 286 287 // The "C" reference locale 288 static _Impl* _S_classic; 289 290 // Current global locale 291 static _Impl* _S_global; 292 293 // Names of underlying locale categories. 294 // NB: locale::global() has to know how to modify all the 295 // underlying categories, not just the ones required by the C++ 296 // standard. 297 static const char* const* const _S_categories; 298 299 // Number of standard categories. For C++, these categories are 300 // collate, ctype, monetary, numeric, time, and messages. These 301 // directly correspond to ISO C99 macros LC_COLLATE, LC_CTYPE, 302 // LC_MONETARY, LC_NUMERIC, and LC_TIME. In addition, POSIX (IEEE 303 // 1003.1-2001) specifies LC_MESSAGES. 304 // In addition to the standard categories, the underlying 305 // operating system is allowed to define extra LC_* 306 // macros. For GNU systems, the following are also valid: 307 // LC_PAPER, LC_NAME, LC_ADDRESS, LC_TELEPHONE, LC_MEASUREMENT, 308 // and LC_IDENTIFICATION. 309 enum { _S_categories_size = 6 + _GLIBCXX_NUM_CATEGORIES }; 310 311#ifdef __GTHREADS 312 static __gthread_once_t _S_once; 313#endif 314 315 explicit 316 locale(_Impl*) throw(); 317 318 static void 319 _S_initialize(); 320 321 static void 322 _S_initialize_once(); 323 324 static category 325 _S_normalize_category(category); 326 327 void 328 _M_coalesce(const locale& __base, const locale& __add, category __cat); 329 }; 330 331 332 // 22.1.1.1.2 Class locale::facet 333 /** 334 * @brief Localization functionality base class. 335 * 336 * The facet class is the base class for a localization feature, such as 337 * money, time, and number printing. It provides common support for facets 338 * and reference management. 339 * 340 * Facets may not be copied or assigned. 341 */ 342 class locale::facet 343 { 344 private: 345 friend class locale; 346 friend class locale::_Impl; 347 348 mutable _Atomic_word _M_refcount; 349 350 // Contains data from the underlying "C" library for the classic locale. 351 static __c_locale _S_c_locale; 352 353 // String literal for the name of the classic locale. 354 static const char _S_c_name[2]; 355 356#ifdef __GTHREADS 357 static __gthread_once_t _S_once; 358#endif 359 360 static void 361 _S_initialize_once(); 362 363 protected: 364 /** 365 * @brief Facet constructor. 366 * 367 * This is the constructor provided by the standard. If refs is 0, the 368 * facet is destroyed when the last referencing locale is destroyed. 369 * Otherwise the facet will never be destroyed. 370 * 371 * @param refs The initial value for reference count. 372 */ 373 explicit 374 facet(size_t __refs = 0) throw() : _M_refcount(__refs ? 1 : 0) 375 { } 376 377 /// Facet destructor. 378 virtual 379 ~facet(); 380 381 static void 382 _S_create_c_locale(__c_locale& __cloc, const char* __s, 383 __c_locale __old = 0); 384 385 static __c_locale 386 _S_clone_c_locale(__c_locale& __cloc); 387 388 static void 389 _S_destroy_c_locale(__c_locale& __cloc); 390 391 // Returns data from the underlying "C" library data for the 392 // classic locale. 393 static __c_locale 394 _S_get_c_locale(); 395 396 static const char* 397 _S_get_c_name(); 398 399 private: 400 inline void 401 _M_add_reference() const throw() 402 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 403 404 inline void 405 _M_remove_reference() const throw() 406 { 407 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 408 { 409 try 410 { delete this; } 411 catch (...) 412 { } 413 } 414 } 415 416 facet(const facet&); // Not defined. 417 418 facet& 419 operator=(const facet&); // Not defined. 420 }; 421 422 423 // 22.1.1.1.3 Class locale::id 424 /** 425 * @brief Facet ID class. 426 * 427 * The ID class provides facets with an index used to identify them. 428 * Every facet class must define a public static member locale::id, or be 429 * derived from a facet that provides this member, otherwise the facet 430 * cannot be used in a locale. The locale::id ensures that each class 431 * type gets a unique identifier. 432 */ 433 class locale::id 434 { 435 private: 436 friend class locale; 437 friend class locale::_Impl; 438 439 template<typename _Facet> 440 friend const _Facet& 441 use_facet(const locale&); 442 443 template<typename _Facet> 444 friend bool 445 has_facet(const locale&) throw (); 446 447 // NB: There is no accessor for _M_index because it may be used 448 // before the constructor is run; the effect of calling a member 449 // function (even an inline) would be undefined. 450 mutable size_t _M_index; 451 452 // Last id number assigned. 453 static _Atomic_word _S_refcount; 454 455 void 456 operator=(const id&); // Not defined. 457 458 id(const id&); // Not defined. 459 460 public: 461 // NB: This class is always a static data member, and thus can be 462 // counted on to be zero-initialized. 463 /// Constructor. 464 id() { } 465 466 size_t 467 _M_id() const; 468 }; 469 470 471 // Implementation object for locale. 472 class locale::_Impl 473 { 474 public: 475 // Friends. 476 friend class locale; 477 friend class locale::facet; 478 479 template<typename _Facet> 480 friend bool 481 has_facet(const locale&) throw(); 482 483 template<typename _Facet> 484 friend const _Facet& 485 use_facet(const locale&); 486 487 template<typename _Cache> 488 friend struct __use_cache; 489 490 private: 491 // Data Members. 492 _Atomic_word _M_refcount; 493 const facet** _M_facets; 494 size_t _M_facets_size; 495 const facet** _M_caches; 496 char** _M_names; 497 static const locale::id* const _S_id_ctype[]; 498 static const locale::id* const _S_id_numeric[]; 499 static const locale::id* const _S_id_collate[]; 500 static const locale::id* const _S_id_time[]; 501 static const locale::id* const _S_id_monetary[]; 502 static const locale::id* const _S_id_messages[]; 503 static const locale::id* const* const _S_facet_categories[]; 504 505 inline void 506 _M_add_reference() throw() 507 { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); } 508 509 inline void 510 _M_remove_reference() throw() 511 { 512 if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1) 513 { 514 try 515 { delete this; } 516 catch(...) 517 { } 518 } 519 } 520 521 _Impl(const _Impl&, size_t); 522 _Impl(const char*, size_t); 523 _Impl(size_t) throw(); 524 525 ~_Impl() throw(); 526 527 _Impl(const _Impl&); // Not defined. 528 529 void 530 operator=(const _Impl&); // Not defined. 531 532 inline bool 533 _M_check_same_name() 534 { 535 bool __ret = true; 536 if (_M_names[1]) 537 // We must actually compare all the _M_names: can be all equal! 538 for (size_t __i = 0; __ret && __i < _S_categories_size - 1; ++__i) 539 __ret = std::strcmp(_M_names[__i], _M_names[__i + 1]) == 0; 540 return __ret; 541 } 542 543 void 544 _M_replace_categories(const _Impl*, category); 545 546 void 547 _M_replace_category(const _Impl*, const locale::id* const*); 548 549 void 550 _M_replace_facet(const _Impl*, const locale::id*); 551 552 void 553 _M_install_facet(const locale::id*, const facet*); 554 555 template<typename _Facet> 556 inline void 557 _M_init_facet(_Facet* __facet) 558 { _M_install_facet(&_Facet::id, __facet); } 559 560 void 561 _M_install_cache(const facet*, size_t); 562 }; 563 564 template<typename _Facet> 565 locale::locale(const locale& __other, _Facet* __f) 566 { 567 _M_impl = new _Impl(*__other._M_impl, 1); 568 569 try 570 { _M_impl->_M_install_facet(&_Facet::id, __f); } 571 catch(...) 572 { 573 _M_impl->_M_remove_reference(); 574 __throw_exception_again; 575 } 576 delete [] _M_impl->_M_names[0]; 577 _M_impl->_M_names[0] = 0; // Unnamed. 578 } 579 580_GLIBCXX_END_NAMESPACE 581 582#endif 583