1 // Locale support (codecvt) -*- C++ -*-
3 // Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
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 2, or (at your option)
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.
16 // You should have received a copy of the GNU General Public License along
17 // with this library; see the file COPYING. If not, write to the Free
18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
21 // As a special exception, you may use this file as part of a free software
22 // library without restriction. Specifically, if other files instantiate
23 // templates or use macros or inline functions from this file, or you compile
24 // this file and link it with other files to produce an executable, this
25 // file does not by itself cause the resulting executable to be covered by
26 // the GNU General Public License. This exception does not however
27 // invalidate any other reasons why the executable file might be covered by
28 // the GNU General Public License.
31 // ISO C++ 14882: 22.2.1.5 Template class codecvt
34 // Warning: this file is not meant for user inclusion. Use <locale>.
36 // Written by Benjamin Kosnik <bkoz@cygnus.com>
39 // Define this here to codecvt.cc can have _S_max_size definition.
40 #define _GLIBCPP_USE___ENC_TRAITS 1
42 // Extension to use icov for dealing with character encodings,
43 // including conversions and comparisons between various character
44 // sets. This object encapsulates data that may need to be shared between
45 // char_traits, codecvt and ctype.
50 // NB: A conversion descriptor subsumes and enhances the
51 // functionality of a simple state type such as mbstate_t.
52 typedef iconv_t __desc_type;
56 // Max size of charset encoding name
57 static const int _S_max_size = 32;
58 // Name of internal character set encoding.
59 char _M_int_enc[_S_max_size];
60 // Name of external character set encoding.
61 char _M_ext_enc[_S_max_size];
63 // Conversion descriptor between external encoding to internal encoding.
64 __desc_type _M_in_desc;
65 // Conversion descriptor between internal encoding to external encoding.
66 __desc_type _M_out_desc;
68 // Details the byte-order marker for the external encoding, if necessary.
71 // Details the byte-order marker for the internal encoding, if necessary.
75 explicit __enc_traits()
76 : _M_in_desc(0), _M_out_desc(0), _M_ext_bom(0), _M_int_bom(0)
78 memset(_M_int_enc, 0, _S_max_size);
79 memset(_M_ext_enc, 0, _S_max_size);
82 explicit __enc_traits(const char* __int, const char* __ext,
83 int __ibom = 0, int __ebom = 0)
84 : _M_in_desc(0), _M_out_desc(0), _M_ext_bom(0), _M_int_bom(0)
86 strncpy(_M_int_enc, __int, _S_max_size);
87 strncpy(_M_ext_enc, __ext, _S_max_size);
90 // 21.1.2 traits typedefs
92 // typedef STATE_T state_type
93 // requires: state_type shall meet the requirements of
94 // CopyConstructible types (20.1.3)
95 __enc_traits(const __enc_traits& __obj): _M_in_desc(0), _M_out_desc(0)
97 strncpy(_M_int_enc, __obj._M_int_enc, _S_max_size);
98 strncpy(_M_ext_enc, __obj._M_ext_enc, _S_max_size);
99 _M_ext_bom = __obj._M_ext_bom;
100 _M_int_bom = __obj._M_int_bom;
103 // Need assignment operator as well.
105 operator=(const __enc_traits& __obj)
107 strncpy(_M_int_enc, __obj._M_int_enc, _S_max_size);
108 strncpy(_M_ext_enc, __obj._M_ext_enc, _S_max_size);
111 _M_ext_bom = __obj._M_ext_bom;
112 _M_int_bom = __obj._M_int_bom;
118 __desc_type __err = reinterpret_cast<iconv_t>(-1);
119 if (_M_in_desc && _M_in_desc != __err)
120 iconv_close(_M_in_desc);
121 if (_M_out_desc && _M_out_desc != __err)
122 iconv_close(_M_out_desc);
128 const __desc_type __err = reinterpret_cast<iconv_t>(-1);
131 _M_in_desc = iconv_open(_M_int_enc, _M_ext_enc);
132 if (_M_in_desc == __err)
133 __throw_runtime_error("creating iconv input descriptor failed.");
137 _M_out_desc = iconv_open(_M_ext_enc, _M_int_enc);
138 if (_M_out_desc == __err)
139 __throw_runtime_error("creating iconv output descriptor failed.");
146 const __desc_type __err = reinterpret_cast<iconv_t>(-1);
147 bool __test = _M_in_desc && _M_in_desc != __err;
148 __test &= _M_out_desc && _M_out_desc != __err;
153 _M_get_in_descriptor()
154 { return &_M_in_desc; }
157 _M_get_out_descriptor()
158 { return &_M_out_desc; }
161 _M_get_external_bom()
162 { return _M_ext_bom; }
165 _M_get_internal_bom()
166 { return _M_int_bom; }
169 _M_get_internal_enc()
170 { return _M_int_enc; }
173 _M_get_external_enc()
174 { return _M_ext_enc; }
177 // Partial specialization
178 // This specialization takes advantage of iconv to provide code
179 // conversions between a large number of character encodings.
180 template<typename _InternT, typename _ExternT>
181 class codecvt<_InternT, _ExternT, __enc_traits>
182 : public __codecvt_abstract_base<_InternT, _ExternT, __enc_traits>
186 typedef codecvt_base::result result;
187 typedef _InternT intern_type;
188 typedef _ExternT extern_type;
189 typedef __enc_traits state_type;
190 typedef __enc_traits::__desc_type __desc_type;
191 typedef __enc_traits __enc_type;
194 static locale::id id;
197 codecvt(size_t __refs = 0)
198 : __codecvt_abstract_base<intern_type, extern_type, state_type>(__refs)
202 codecvt(__enc_type* __enc, size_t __refs = 0)
203 : __codecvt_abstract_base<intern_type, extern_type, state_type>(__refs)
211 do_out(state_type& __state, const intern_type* __from,
212 const intern_type* __from_end, const intern_type*& __from_next,
213 extern_type* __to, extern_type* __to_end,
214 extern_type*& __to_next) const;
217 do_unshift(state_type& __state, extern_type* __to,
218 extern_type* __to_end, extern_type*& __to_next) const;
221 do_in(state_type& __state, const extern_type* __from,
222 const extern_type* __from_end, const extern_type*& __from_next,
223 intern_type* __to, intern_type* __to_end,
224 intern_type*& __to_next) const;
227 do_encoding() const throw();
230 do_always_noconv() const throw();
233 do_length(const state_type&, const extern_type* __from,
234 const extern_type* __end, size_t __max) const;
237 do_max_length() const throw();
240 template<typename _InternT, typename _ExternT>
242 codecvt<_InternT, _ExternT, __enc_traits>::id;
244 // This adaptor works around the signature problems of the second
245 // argument to iconv(): SUSv2 and others use 'const char**', but glibc 2.2
246 // uses 'char**', which matches the POSIX 1003.1-2001 standard.
247 // Using this adaptor, g++ will do the work for us.
248 template<typename _T>
250 __iconv_adaptor(size_t(*__func)(iconv_t, _T, size_t*, char**, size_t*),
251 iconv_t __cd, char** __inbuf, size_t* __inbytes,
252 char** __outbuf, size_t* __outbytes)
253 { return __func(__cd, (_T)__inbuf, __inbytes, __outbuf, __outbytes); }
255 template<typename _InternT, typename _ExternT>
257 codecvt<_InternT, _ExternT, __enc_traits>::
258 do_out(state_type& __state, const intern_type* __from,
259 const intern_type* __from_end, const intern_type*& __from_next,
260 extern_type* __to, extern_type* __to_end,
261 extern_type*& __to_next) const
263 result __ret = codecvt_base::error;
264 if (__state._M_good())
266 typedef state_type::__desc_type __desc_type;
267 const __desc_type* __desc = __state._M_get_out_descriptor();
268 const size_t __fmultiple = sizeof(intern_type);
269 size_t __fbytes = __fmultiple * (__from_end - __from);
270 const size_t __tmultiple = sizeof(extern_type);
271 size_t __tbytes = __tmultiple * (__to_end - __to);
273 // Argument list for iconv specifies a byte sequence. Thus,
274 // all to/from arrays must be brutally casted to char*.
275 char* __cto = reinterpret_cast<char*>(__to);
279 // Some encodings need a byte order marker as the first item
280 // in the byte stream, to designate endian-ness. The default
281 // value for the byte order marker is NULL, so if this is
282 // the case, it's not necessary and we can just go on our
284 int __int_bom = __state._M_get_internal_bom();
287 size_t __size = __from_end - __from;
288 intern_type* __cfixed = static_cast<intern_type*>(__builtin_alloca(sizeof(intern_type) * (__size + 1)));
289 __cfixed[0] = static_cast<intern_type>(__int_bom);
290 char_traits<intern_type>::copy(__cfixed + 1, __from, __size);
291 __cfrom = reinterpret_cast<char*>(__cfixed);
292 __conv = __iconv_adaptor(iconv, *__desc, &__cfrom,
293 &__fbytes, &__cto, &__tbytes);
297 intern_type* __cfixed = const_cast<intern_type*>(__from);
298 __cfrom = reinterpret_cast<char*>(__cfixed);
299 __conv = __iconv_adaptor(iconv, *__desc, &__cfrom, &__fbytes,
303 if (__conv != size_t(-1))
305 __from_next = reinterpret_cast<const intern_type*>(__cfrom);
306 __to_next = reinterpret_cast<extern_type*>(__cto);
307 __ret = codecvt_base::ok;
311 if (__fbytes < __fmultiple * (__from_end - __from))
313 __from_next = reinterpret_cast<const intern_type*>(__cfrom);
314 __to_next = reinterpret_cast<extern_type*>(__cto);
315 __ret = codecvt_base::partial;
318 __ret = codecvt_base::error;
324 template<typename _InternT, typename _ExternT>
326 codecvt<_InternT, _ExternT, __enc_traits>::
327 do_unshift(state_type& __state, extern_type* __to,
328 extern_type* __to_end, extern_type*& __to_next) const
330 result __ret = codecvt_base::error;
331 if (__state._M_good())
333 typedef state_type::__desc_type __desc_type;
334 const __desc_type* __desc = __state._M_get_in_descriptor();
335 const size_t __tmultiple = sizeof(intern_type);
336 size_t __tlen = __tmultiple * (__to_end - __to);
338 // Argument list for iconv specifies a byte sequence. Thus,
339 // all to/from arrays must be brutally casted to char*.
340 char* __cto = reinterpret_cast<char*>(__to);
341 size_t __conv = __iconv_adaptor(iconv,*__desc, NULL, NULL,
344 if (__conv != size_t(-1))
346 __to_next = reinterpret_cast<extern_type*>(__cto);
347 if (__tlen == __tmultiple * (__to_end - __to))
348 __ret = codecvt_base::noconv;
349 else if (__tlen == 0)
350 __ret = codecvt_base::ok;
352 __ret = codecvt_base::partial;
355 __ret = codecvt_base::error;
360 template<typename _InternT, typename _ExternT>
362 codecvt<_InternT, _ExternT, __enc_traits>::
363 do_in(state_type& __state, const extern_type* __from,
364 const extern_type* __from_end, const extern_type*& __from_next,
365 intern_type* __to, intern_type* __to_end,
366 intern_type*& __to_next) const
368 result __ret = codecvt_base::error;
369 if (__state._M_good())
371 typedef state_type::__desc_type __desc_type;
372 const __desc_type* __desc = __state._M_get_in_descriptor();
373 const size_t __fmultiple = sizeof(extern_type);
374 size_t __flen = __fmultiple * (__from_end - __from);
375 const size_t __tmultiple = sizeof(intern_type);
376 size_t __tlen = __tmultiple * (__to_end - __to);
378 // Argument list for iconv specifies a byte sequence. Thus,
379 // all to/from arrays must be brutally casted to char*.
380 char* __cto = reinterpret_cast<char*>(__to);
384 // Some encodings need a byte order marker as the first item
385 // in the byte stream, to designate endian-ness. The default
386 // value for the byte order marker is NULL, so if this is
387 // the case, it's not necessary and we can just go on our
389 int __ext_bom = __state._M_get_external_bom();
392 size_t __size = __from_end - __from;
393 extern_type* __cfixed = static_cast<extern_type*>(__builtin_alloca(sizeof(extern_type) * (__size + 1)));
394 __cfixed[0] = static_cast<extern_type>(__ext_bom);
395 char_traits<extern_type>::copy(__cfixed + 1, __from, __size);
396 __cfrom = reinterpret_cast<char*>(__cfixed);
397 __conv = __iconv_adaptor(iconv, *__desc, &__cfrom,
398 &__flen, &__cto, &__tlen);
402 extern_type* __cfixed = const_cast<extern_type*>(__from);
403 __cfrom = reinterpret_cast<char*>(__cfixed);
404 __conv = __iconv_adaptor(iconv, *__desc, &__cfrom,
405 &__flen, &__cto, &__tlen);
409 if (__conv != size_t(-1))
411 __from_next = reinterpret_cast<const extern_type*>(__cfrom);
412 __to_next = reinterpret_cast<intern_type*>(__cto);
413 __ret = codecvt_base::ok;
417 if (__flen < static_cast<size_t>(__from_end - __from))
419 __from_next = reinterpret_cast<const extern_type*>(__cfrom);
420 __to_next = reinterpret_cast<intern_type*>(__cto);
421 __ret = codecvt_base::partial;
424 __ret = codecvt_base::error;
430 template<typename _InternT, typename _ExternT>
432 codecvt<_InternT, _ExternT, __enc_traits>::
433 do_encoding() const throw()
436 if (sizeof(_ExternT) <= sizeof(_InternT))
437 __ret = sizeof(_InternT)/sizeof(_ExternT);
441 template<typename _InternT, typename _ExternT>
443 codecvt<_InternT, _ExternT, __enc_traits>::
444 do_always_noconv() const throw()
447 template<typename _InternT, typename _ExternT>
449 codecvt<_InternT, _ExternT, __enc_traits>::
450 do_length(const state_type&, const extern_type* __from,
451 const extern_type* __end, size_t __max) const
452 { return min(__max, static_cast<size_t>(__end - __from)); }
454 #ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS
455 // 74. Garbled text for codecvt::do_max_length
456 template<typename _InternT, typename _ExternT>
458 codecvt<_InternT, _ExternT, __enc_traits>::
459 do_max_length() const throw()