1// Locale support (codecvt) -*- C++ -*-
2
3// Copyright (C) 2000-2021 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/codecvt.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: 22.2.1.5 Template class codecvt
32//
33
34// Written by Benjamin Kosnik <bkoz@redhat.com>
35
36#ifndef _CODECVT_H
37#define _CODECVT_H 1
38
39#pragma GCC system_header
40
41#include <bits/c++config.h>
42#include <bits/locale_classes.h> // locale::facet
43
44namespace std _GLIBCXX_VISIBILITY(default)
45{
46_GLIBCXX_BEGIN_NAMESPACE_VERSION
47
48 /// Empty base class for codecvt facet [22.2.1.5].
49 class codecvt_base
50 {
51 public:
52 enum result
53 {
54 ok,
55 partial,
56 error,
57 noconv
58 };
59 };
60
61 /**
62 * @brief Common base for codecvt functions.
63 *
64 * This template class provides implementations of the public functions
65 * that forward to the protected virtual functions.
66 *
67 * This template also provides abstract stubs for the protected virtual
68 * functions.
69 */
70 template<typename _InternT, typename _ExternT, typename _StateT>
71 class __codecvt_abstract_base
72 : public locale::facet, public codecvt_base
73 {
74 public:
75 // Types:
76 typedef codecvt_base::result result;
77 typedef _InternT intern_type;
78 typedef _ExternT extern_type;
79 typedef _StateT state_type;
80
81 // 22.2.1.5.1 codecvt members
82 /**
83 * @brief Convert from internal to external character set.
84 *
85 * Converts input string of intern_type to output string of
86 * extern_type. This is analogous to wcsrtombs. It does this by
87 * calling codecvt::do_out.
88 *
89 * The source and destination character sets are determined by the
90 * facet's locale, internal and external types.
91 *
92 * The characters in [from,from_end) are converted and written to
93 * [to,to_end). from_next and to_next are set to point to the
94 * character following the last successfully converted character,
95 * respectively. If the result needed no conversion, from_next and
96 * to_next are not affected.
97 *
98 * The @a state argument should be initialized if the input is at the
99 * beginning and carried from a previous call if continuing
100 * conversion. There are no guarantees about how @a state is used.
101 *
102 * The result returned is a member of codecvt_base::result. If
103 * all the input is converted, returns codecvt_base::ok. If no
104 * conversion is necessary, returns codecvt_base::noconv. If
105 * the input ends early or there is insufficient space in the
106 * output, returns codecvt_base::partial. Otherwise the
107 * conversion failed and codecvt_base::error is returned.
108 *
109 * @param __state Persistent conversion state data.
110 * @param __from Start of input.
111 * @param __from_end End of input.
112 * @param __from_next Returns start of unconverted data.
113 * @param __to Start of output buffer.
114 * @param __to_end End of output buffer.
115 * @param __to_next Returns start of unused output area.
116 * @return codecvt_base::result.
117 */
118 result
119 out(state_type& __state, const intern_type* __from,
120 const intern_type* __from_end, const intern_type*& __from_next,
121 extern_type* __to, extern_type* __to_end,
122 extern_type*& __to_next) const
123 {
124 return this->do_out(__state, __from, __from_end, __from_next,
125 __to, __to_end, __to_next);
126 }
127
128 /**
129 * @brief Reset conversion state.
130 *
131 * Writes characters to output that would restore @a state to initial
132 * conditions. The idea is that if a partial conversion occurs, then
133 * the converting the characters written by this function would leave
134 * the state in initial conditions, rather than partial conversion
135 * state. It does this by calling codecvt::do_unshift().
136 *
137 * For example, if 4 external characters always converted to 1 internal
138 * character, and input to in() had 6 external characters with state
139 * saved, this function would write two characters to the output and
140 * set the state to initialized conditions.
141 *
142 * The source and destination character sets are determined by the
143 * facet's locale, internal and external types.
144 *
145 * The result returned is a member of codecvt_base::result. If the
146 * state could be reset and data written, returns codecvt_base::ok. If
147 * no conversion is necessary, returns codecvt_base::noconv. If the
148 * output has insufficient space, returns codecvt_base::partial.
149 * Otherwise the reset failed and codecvt_base::error is returned.
150 *
151 * @param __state Persistent conversion state data.
152 * @param __to Start of output buffer.
153 * @param __to_end End of output buffer.
154 * @param __to_next Returns start of unused output area.
155 * @return codecvt_base::result.
156 */
157 result
158 unshift(state_type& __state, extern_type* __to, extern_type* __to_end,
159 extern_type*& __to_next) const
160 { return this->do_unshift(__state, __to,__to_end,__to_next); }
161
162 /**
163 * @brief Convert from external to internal character set.
164 *
165 * Converts input string of extern_type to output string of
166 * intern_type. This is analogous to mbsrtowcs. It does this by
167 * calling codecvt::do_in.
168 *
169 * The source and destination character sets are determined by the
170 * facet's locale, internal and external types.
171 *
172 * The characters in [from,from_end) are converted and written to
173 * [to,to_end). from_next and to_next are set to point to the
174 * character following the last successfully converted character,
175 * respectively. If the result needed no conversion, from_next and
176 * to_next are not affected.
177 *
178 * The @a state argument should be initialized if the input is at the
179 * beginning and carried from a previous call if continuing
180 * conversion. There are no guarantees about how @a state is used.
181 *
182 * The result returned is a member of codecvt_base::result. If
183 * all the input is converted, returns codecvt_base::ok. If no
184 * conversion is necessary, returns codecvt_base::noconv. If
185 * the input ends early or there is insufficient space in the
186 * output, returns codecvt_base::partial. Otherwise the
187 * conversion failed and codecvt_base::error is returned.
188 *
189 * @param __state Persistent conversion state data.
190 * @param __from Start of input.
191 * @param __from_end End of input.
192 * @param __from_next Returns start of unconverted data.
193 * @param __to Start of output buffer.
194 * @param __to_end End of output buffer.
195 * @param __to_next Returns start of unused output area.
196 * @return codecvt_base::result.
197 */
198 result
199 in(state_type& __state, const extern_type* __from,
200 const extern_type* __from_end, const extern_type*& __from_next,
201 intern_type* __to, intern_type* __to_end,
202 intern_type*& __to_next) const
203 {
204 return this->do_in(__state, __from, __from_end, __from_next,
205 __to, __to_end, __to_next);
206 }
207
208 int
209 encoding() const throw()
210 { return this->do_encoding(); }
211
212 bool
213 always_noconv() const throw()
214 { return this->do_always_noconv(); }
215
216 int
217 length(state_type& __state, const extern_type* __from,
218 const extern_type* __end, size_t __max) const
219 { return this->do_length(__state, __from, __end, __max); }
220
221 int
222 max_length() const throw()
223 { return this->do_max_length(); }
224
225 protected:
226 explicit
227 __codecvt_abstract_base(size_t __refs = 0) : locale::facet(__refs) { }
228
229 virtual
230 ~__codecvt_abstract_base() { }
231
232 /**
233 * @brief Convert from internal to external character set.
234 *
235 * Converts input string of intern_type to output string of
236 * extern_type. This function is a hook for derived classes to change
237 * the value returned. @see out for more information.
238 */
239 virtual result
240 do_out(state_type& __state, const intern_type* __from,
241 const intern_type* __from_end, const intern_type*& __from_next,
242 extern_type* __to, extern_type* __to_end,
243 extern_type*& __to_next) const = 0;
244
245 virtual result
246 do_unshift(state_type& __state, extern_type* __to,
247 extern_type* __to_end, extern_type*& __to_next) const = 0;
248
249 virtual result
250 do_in(state_type& __state, const extern_type* __from,
251 const extern_type* __from_end, const extern_type*& __from_next,
252 intern_type* __to, intern_type* __to_end,
253 intern_type*& __to_next) const = 0;
254
255 virtual int
256 do_encoding() const throw() = 0;
257
258 virtual bool
259 do_always_noconv() const throw() = 0;
260
261 virtual int
262 do_length(state_type&, const extern_type* __from,
263 const extern_type* __end, size_t __max) const = 0;
264
265 virtual int
266 do_max_length() const throw() = 0;
267 };
268
269 /**
270 * @brief Primary class template codecvt.
271 * @ingroup locales
272 *
273 * NB: Generic, mostly useless implementation.
274 *
275 */
276 template<typename _InternT, typename _ExternT, typename _StateT>
277 class codecvt
278 : public __codecvt_abstract_base<_InternT, _ExternT, _StateT>
279 {
280 public:
281 // Types:
282 typedef codecvt_base::result result;
283 typedef _InternT intern_type;
284 typedef _ExternT extern_type;
285 typedef _StateT state_type;
286
287 protected:
288 __c_locale _M_c_locale_codecvt;
289
290 public:
291 static locale::id id;
292
293 explicit
294 codecvt(size_t __refs = 0)
295 : __codecvt_abstract_base<_InternT, _ExternT, _StateT> (__refs),
296 _M_c_locale_codecvt(0)
297 { }
298
299 explicit
300 codecvt(__c_locale __cloc, size_t __refs = 0);
301
302 protected:
303 virtual
304 ~codecvt() { }
305
306 virtual result
307 do_out(state_type& __state, const intern_type* __from,
308 const intern_type* __from_end, const intern_type*& __from_next,
309 extern_type* __to, extern_type* __to_end,
310 extern_type*& __to_next) const;
311
312 virtual result
313 do_unshift(state_type& __state, extern_type* __to,
314 extern_type* __to_end, extern_type*& __to_next) const;
315
316 virtual result
317 do_in(state_type& __state, const extern_type* __from,
318 const extern_type* __from_end, const extern_type*& __from_next,
319 intern_type* __to, intern_type* __to_end,
320 intern_type*& __to_next) const;
321
322 virtual int
323 do_encoding() const throw();
324
325 virtual bool
326 do_always_noconv() const throw();
327
328 virtual int
329 do_length(state_type&, const extern_type* __from,
330 const extern_type* __end, size_t __max) const;
331
332 virtual int
333 do_max_length() const throw();
334 };
335
336 template<typename _InternT, typename _ExternT, typename _StateT>
337 locale::id codecvt<_InternT, _ExternT, _StateT>::id;
338
339 /// class codecvt<char, char, mbstate_t> specialization.
340 template<>
341 class codecvt<char, char, mbstate_t>
342 : public __codecvt_abstract_base<char, char, mbstate_t>
343 {
344 friend class messages<char>;
345
346 public:
347 // Types:
348 typedef char intern_type;
349 typedef char extern_type;
350 typedef mbstate_t state_type;
351
352 protected:
353 __c_locale _M_c_locale_codecvt;
354
355 public:
356 static locale::id id;
357
358 explicit
359 codecvt(size_t __refs = 0);
360
361 explicit
362 codecvt(__c_locale __cloc, size_t __refs = 0);
363
364 protected:
365 virtual
366 ~codecvt();
367
368 virtual result
369 do_out(state_type& __state, const intern_type* __from,
370 const intern_type* __from_end, const intern_type*& __from_next,
371 extern_type* __to, extern_type* __to_end,
372 extern_type*& __to_next) const;
373
374 virtual result
375 do_unshift(state_type& __state, extern_type* __to,
376 extern_type* __to_end, extern_type*& __to_next) const;
377
378 virtual result
379 do_in(state_type& __state, const extern_type* __from,
380 const extern_type* __from_end, const extern_type*& __from_next,
381 intern_type* __to, intern_type* __to_end,
382 intern_type*& __to_next) const;
383
384 virtual int
385 do_encoding() const throw();
386
387 virtual bool
388 do_always_noconv() const throw();
389
390 virtual int
391 do_length(state_type&, const extern_type* __from,
392 const extern_type* __end, size_t __max) const;
393
394 virtual int
395 do_max_length() const throw();
396 };
397
398#ifdef _GLIBCXX_USE_WCHAR_T
399 /** @brief Class codecvt<wchar_t, char, mbstate_t> specialization.
400 *
401 * Converts between narrow and wide characters in the native character set
402 */
403 template<>
404 class codecvt<wchar_t, char, mbstate_t>
405 : public __codecvt_abstract_base<wchar_t, char, mbstate_t>
406 {
407 friend class messages<wchar_t>;
408
409 public:
410 // Types:
411 typedef wchar_t intern_type;
412 typedef char extern_type;
413 typedef mbstate_t state_type;
414
415 protected:
416 __c_locale _M_c_locale_codecvt;
417
418 public:
419 static locale::id id;
420
421 explicit
422 codecvt(size_t __refs = 0);
423
424 explicit
425 codecvt(__c_locale __cloc, size_t __refs = 0);
426
427 protected:
428 virtual
429 ~codecvt();
430
431 virtual result
432 do_out(state_type& __state, const intern_type* __from,
433 const intern_type* __from_end, const intern_type*& __from_next,
434 extern_type* __to, extern_type* __to_end,
435 extern_type*& __to_next) const;
436
437 virtual result
438 do_unshift(state_type& __state,
439 extern_type* __to, extern_type* __to_end,
440 extern_type*& __to_next) const;
441
442 virtual result
443 do_in(state_type& __state,
444 const extern_type* __from, const extern_type* __from_end,
445 const extern_type*& __from_next,
446 intern_type* __to, intern_type* __to_end,
447 intern_type*& __to_next) const;
448
449 virtual
450 int do_encoding() const throw();
451
452 virtual
453 bool do_always_noconv() const throw();
454
455 virtual
456 int do_length(state_type&, const extern_type* __from,
457 const extern_type* __end, size_t __max) const;
458
459 virtual int
460 do_max_length() const throw();
461 };
462#endif //_GLIBCXX_USE_WCHAR_T
463
464#if __cplusplus >= 201103L
465 /** @brief Class codecvt<char16_t, char, mbstate_t> specialization.
466 *
467 * Converts between UTF-16 and UTF-8.
468 */
469 template<>
470 class codecvt<char16_t, char, mbstate_t>
471 : public __codecvt_abstract_base<char16_t, char, mbstate_t>
472 {
473 public:
474 // Types:
475 typedef char16_t intern_type;
476 typedef char extern_type;
477 typedef mbstate_t state_type;
478
479 public:
480 static locale::id id;
481
482 explicit
483 codecvt(size_t __refs = 0)
484 : __codecvt_abstract_base<char16_t, char, mbstate_t>(__refs) { }
485
486 protected:
487 virtual
488 ~codecvt();
489
490 virtual result
491 do_out(state_type& __state, const intern_type* __from,
492 const intern_type* __from_end, const intern_type*& __from_next,
493 extern_type* __to, extern_type* __to_end,
494 extern_type*& __to_next) const;
495
496 virtual result
497 do_unshift(state_type& __state,
498 extern_type* __to, extern_type* __to_end,
499 extern_type*& __to_next) const;
500
501 virtual result
502 do_in(state_type& __state,
503 const extern_type* __from, const extern_type* __from_end,
504 const extern_type*& __from_next,
505 intern_type* __to, intern_type* __to_end,
506 intern_type*& __to_next) const;
507
508 virtual
509 int do_encoding() const throw();
510
511 virtual
512 bool do_always_noconv() const throw();
513
514 virtual
515 int do_length(state_type&, const extern_type* __from,
516 const extern_type* __end, size_t __max) const;
517
518 virtual int
519 do_max_length() const throw();
520 };
521
522 /** @brief Class codecvt<char32_t, char, mbstate_t> specialization.
523 *
524 * Converts between UTF-32 and UTF-8.
525 */
526 template<>
527 class codecvt<char32_t, char, mbstate_t>
528 : public __codecvt_abstract_base<char32_t, char, mbstate_t>
529 {
530 public:
531 // Types:
532 typedef char32_t intern_type;
533 typedef char extern_type;
534 typedef mbstate_t state_type;
535
536 public:
537 static locale::id id;
538
539 explicit
540 codecvt(size_t __refs = 0)
541 : __codecvt_abstract_base<char32_t, char, mbstate_t>(__refs) { }
542
543 protected:
544 virtual
545 ~codecvt();
546
547 virtual result
548 do_out(state_type& __state, const intern_type* __from,
549 const intern_type* __from_end, const intern_type*& __from_next,
550 extern_type* __to, extern_type* __to_end,
551 extern_type*& __to_next) const;
552
553 virtual result
554 do_unshift(state_type& __state,
555 extern_type* __to, extern_type* __to_end,
556 extern_type*& __to_next) const;
557
558 virtual result
559 do_in(state_type& __state,
560 const extern_type* __from, const extern_type* __from_end,
561 const extern_type*& __from_next,
562 intern_type* __to, intern_type* __to_end,
563 intern_type*& __to_next) const;
564
565 virtual
566 int do_encoding() const throw();
567
568 virtual
569 bool do_always_noconv() const throw();
570
571 virtual
572 int do_length(state_type&, const extern_type* __from,
573 const extern_type* __end, size_t __max) const;
574
575 virtual int
576 do_max_length() const throw();
577 };
578
579#ifdef _GLIBCXX_USE_CHAR8_T
580 /** @brief Class codecvt<char16_t, char8_t, mbstate_t> specialization.
581 *
582 * Converts between UTF-16 and UTF-8.
583 */
584 template<>
585 class codecvt<char16_t, char8_t, mbstate_t>
586 : public __codecvt_abstract_base<char16_t, char8_t, mbstate_t>
587 {
588 public:
589 // Types:
590 typedef char16_t intern_type;
591 typedef char8_t extern_type;
592 typedef mbstate_t state_type;
593
594 public:
595 static locale::id id;
596
597 explicit
598 codecvt(size_t __refs = 0)
599 : __codecvt_abstract_base<char16_t, char8_t, mbstate_t>(__refs) { }
600
601 protected:
602 virtual
603 ~codecvt();
604
605 virtual result
606 do_out(state_type& __state, const intern_type* __from,
607 const intern_type* __from_end, const intern_type*& __from_next,
608 extern_type* __to, extern_type* __to_end,
609 extern_type*& __to_next) const;
610
611 virtual result
612 do_unshift(state_type& __state,
613 extern_type* __to, extern_type* __to_end,
614 extern_type*& __to_next) const;
615
616 virtual result
617 do_in(state_type& __state,
618 const extern_type* __from, const extern_type* __from_end,
619 const extern_type*& __from_next,
620 intern_type* __to, intern_type* __to_end,
621 intern_type*& __to_next) const;
622
623 virtual
624 int do_encoding() const throw();
625
626 virtual
627 bool do_always_noconv() const throw();
628
629 virtual
630 int do_length(state_type&, const extern_type* __from,
631 const extern_type* __end, size_t __max) const;
632
633 virtual int
634 do_max_length() const throw();
635 };
636
637 /** @brief Class codecvt<char32_t, char8_t, mbstate_t> specialization.
638 *
639 * Converts between UTF-32 and UTF-8.
640 */
641 template<>
642 class codecvt<char32_t, char8_t, mbstate_t>
643 : public __codecvt_abstract_base<char32_t, char8_t, mbstate_t>
644 {
645 public:
646 // Types:
647 typedef char32_t intern_type;
648 typedef char8_t extern_type;
649 typedef mbstate_t state_type;
650
651 public:
652 static locale::id id;
653
654 explicit
655 codecvt(size_t __refs = 0)
656 : __codecvt_abstract_base<char32_t, char8_t, mbstate_t>(__refs) { }
657
658 protected:
659 virtual
660 ~codecvt();
661
662 virtual result
663 do_out(state_type& __state, const intern_type* __from,
664 const intern_type* __from_end, const intern_type*& __from_next,
665 extern_type* __to, extern_type* __to_end,
666 extern_type*& __to_next) const;
667
668 virtual result
669 do_unshift(state_type& __state,
670 extern_type* __to, extern_type* __to_end,
671 extern_type*& __to_next) const;
672
673 virtual result
674 do_in(state_type& __state,
675 const extern_type* __from, const extern_type* __from_end,
676 const extern_type*& __from_next,
677 intern_type* __to, intern_type* __to_end,
678 intern_type*& __to_next) const;
679
680 virtual
681 int do_encoding() const throw();
682
683 virtual
684 bool do_always_noconv() const throw();
685
686 virtual
687 int do_length(state_type&, const extern_type* __from,
688 const extern_type* __end, size_t __max) const;
689
690 virtual int
691 do_max_length() const throw();
692 };
693#endif // _GLIBCXX_USE_CHAR8_T
694
695#endif // C++11
696
697 /// class codecvt_byname [22.2.1.6].
698 template<typename _InternT, typename _ExternT, typename _StateT>
699 class codecvt_byname : public codecvt<_InternT, _ExternT, _StateT>
700 {
701 public:
702 explicit
703 codecvt_byname(const char* __s, size_t __refs = 0)
704 : codecvt<_InternT, _ExternT, _StateT>(__refs)
705 {
706 if (__builtin_strcmp(__s, "C") != 0
707 && __builtin_strcmp(__s, "POSIX") != 0)
708 {
709 this->_S_destroy_c_locale(this->_M_c_locale_codecvt);
710 this->_S_create_c_locale(this->_M_c_locale_codecvt, __s);
711 }
712 }
713
714#if __cplusplus >= 201103L
715 explicit
716 codecvt_byname(const string& __s, size_t __refs = 0)
717 : codecvt_byname(__s.c_str(), __refs) { }
718#endif
719
720 protected:
721 virtual
722 ~codecvt_byname() { }
723 };
724
725#if __cplusplus >= 201103L
726 template<>
727 class codecvt_byname<char16_t, char, mbstate_t>
728 : public codecvt<char16_t, char, mbstate_t>
729 {
730 public:
731 explicit
732 codecvt_byname(const char*, size_t __refs = 0)
733 : codecvt<char16_t, char, mbstate_t>(__refs) { }
734
735 explicit
736 codecvt_byname(const string& __s, size_t __refs = 0)
737 : codecvt_byname(__s.c_str(), __refs) { }
738
739 protected:
740 virtual
741 ~codecvt_byname() { }
742 };
743
744 template<>
745 class codecvt_byname<char32_t, char, mbstate_t>
746 : public codecvt<char32_t, char, mbstate_t>
747 {
748 public:
749 explicit
750 codecvt_byname(const char*, size_t __refs = 0)
751 : codecvt<char32_t, char, mbstate_t>(__refs) { }
752
753 explicit
754 codecvt_byname(const string& __s, size_t __refs = 0)
755 : codecvt_byname(__s.c_str(), __refs) { }
756
757 protected:
758 virtual
759 ~codecvt_byname() { }
760 };
761
762#if defined(_GLIBCXX_USE_CHAR8_T)
763 template<>
764 class codecvt_byname<char16_t, char8_t, mbstate_t>
765 : public codecvt<char16_t, char8_t, mbstate_t>
766 {
767 public:
768 explicit
769 codecvt_byname(const char*, size_t __refs = 0)
770 : codecvt<char16_t, char8_t, mbstate_t>(__refs) { }
771
772 explicit
773 codecvt_byname(const string& __s, size_t __refs = 0)
774 : codecvt_byname(__s.c_str(), __refs) { }
775
776 protected:
777 virtual
778 ~codecvt_byname() { }
779 };
780
781 template<>
782 class codecvt_byname<char32_t, char8_t, mbstate_t>
783 : public codecvt<char32_t, char8_t, mbstate_t>
784 {
785 public:
786 explicit
787 codecvt_byname(const char*, size_t __refs = 0)
788 : codecvt<char32_t, char8_t, mbstate_t>(__refs) { }
789
790 explicit
791 codecvt_byname(const string& __s, size_t __refs = 0)
792 : codecvt_byname(__s.c_str(), __refs) { }
793
794 protected:
795 virtual
796 ~codecvt_byname() { }
797 };
798#endif
799
800#endif // C++11
801
802 // Inhibit implicit instantiations for required instantiations,
803 // which are defined via explicit instantiations elsewhere.
804#if _GLIBCXX_EXTERN_TEMPLATE
805 extern template class codecvt_byname<char, char, mbstate_t>;
806
807 extern template
808 const codecvt<char, char, mbstate_t>&
809 use_facet<codecvt<char, char, mbstate_t> >(const locale&);
810
811 extern template
812 bool
813 has_facet<codecvt<char, char, mbstate_t> >(const locale&);
814
815#ifdef _GLIBCXX_USE_WCHAR_T
816 extern template class codecvt_byname<wchar_t, char, mbstate_t>;
817
818 extern template
819 const codecvt<wchar_t, char, mbstate_t>&
820 use_facet<codecvt<wchar_t, char, mbstate_t> >(const locale&);
821
822 extern template
823 bool
824 has_facet<codecvt<wchar_t, char, mbstate_t> >(const locale&);
825#endif
826
827#if __cplusplus >= 201103L
828 extern template class codecvt_byname<char16_t, char, mbstate_t>;
829 extern template class codecvt_byname<char32_t, char, mbstate_t>;
830
831#if defined(_GLIBCXX_USE_CHAR8_T)
832 extern template class codecvt_byname<char16_t, char8_t, mbstate_t>;
833 extern template class codecvt_byname<char32_t, char8_t, mbstate_t>;
834#endif
835
836#endif
837
838#endif
839
840_GLIBCXX_END_NAMESPACE_VERSION
841} // namespace std
842
843#endif // _CODECVT_H
844

source code of include/c++/11/bits/codecvt.h