1 // wstring_convert implementation -*- C++ -*-
3 // Copyright (C) 2015-2019 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 3, 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 // 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.
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/>.
25 /** @file bits/locale_conv.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{locale}
30 #ifndef _LOCALE_CONV_H
31 #define _LOCALE_CONV_H 1
33 #if __cplusplus < 201103L
34 # include <bits/c++0x_warning.h>
38 #include <bits/stringfwd.h>
39 #include <bits/allocator.h>
40 #include <bits/codecvt.h>
41 #include <bits/unique_ptr.h>
43 namespace std
_GLIBCXX_VISIBILITY(default)
45 _GLIBCXX_BEGIN_NAMESPACE_VERSION
52 template<typename _OutStr
, typename _InChar
, typename _Codecvt
,
53 typename _State
, typename _Fn
>
55 __do_str_codecvt(const _InChar
* __first
, const _InChar
* __last
,
56 _OutStr
& __outstr
, const _Codecvt
& __cvt
, _State
& __state
,
57 size_t& __count
, _Fn __fn
)
59 if (__first
== __last
)
66 size_t __outchars
= 0;
67 auto __next
= __first
;
68 const auto __maxlen
= __cvt
.max_length() + 1;
70 codecvt_base::result __result
;
73 __outstr
.resize(__outstr
.size() + (__last
- __next
) * __maxlen
);
74 auto __outnext
= &__outstr
.front() + __outchars
;
75 auto const __outlast
= &__outstr
.back() + 1;
76 __result
= (__cvt
.*__fn
)(__state
, __next
, __last
, __next
,
77 __outnext
, __outlast
, __outnext
);
78 __outchars
= __outnext
- &__outstr
.front();
80 while (__result
== codecvt_base::partial
&& __next
!= __last
81 && (__outstr
.size() - __outchars
) < __maxlen
);
83 if (__result
== codecvt_base::error
)
85 __count
= __next
- __first
;
89 // The codecvt facet will only return noconv when the types are
90 // the same, so avoid instantiating basic_string::assign otherwise
91 if _GLIBCXX17_CONSTEXPR (is_same
<typename
_Codecvt::intern_type
,
92 typename
_Codecvt::extern_type
>())
93 if (__result
== codecvt_base::noconv
)
95 __outstr
.assign(__first
, __last
);
96 __count
= __last
- __first
;
100 __outstr
.resize(__outchars
);
101 __count
= __next
- __first
;
105 // Convert narrow character string to wide.
106 template<typename _CharT
, typename _Traits
, typename _Alloc
, typename _State
>
108 __str_codecvt_in(const char* __first
, const char* __last
,
109 basic_string
<_CharT
, _Traits
, _Alloc
>& __outstr
,
110 const codecvt
<_CharT
, char, _State
>& __cvt
,
111 _State
& __state
, size_t& __count
)
113 using _Codecvt
= codecvt
<_CharT
, char, _State
>;
115 = codecvt_base::result
116 (_Codecvt::*)(_State
&, const char*, const char*, const char*&,
117 _CharT
*, _CharT
*, _CharT
*&) const;
118 _ConvFn __fn
= &codecvt
<_CharT
, char, _State
>::in
;
119 return __do_str_codecvt(__first
, __last
, __outstr
, __cvt
, __state
,
123 // As above, but with no __count parameter
124 template<typename _CharT
, typename _Traits
, typename _Alloc
, typename _State
>
126 __str_codecvt_in(const char* __first
, const char* __last
,
127 basic_string
<_CharT
, _Traits
, _Alloc
>& __outstr
,
128 const codecvt
<_CharT
, char, _State
>& __cvt
)
132 return __str_codecvt_in(__first
, __last
, __outstr
, __cvt
, __state
, __n
);
135 // As above, but returns false for partial conversion
136 template<typename _CharT
, typename _Traits
, typename _Alloc
, typename _State
>
138 __str_codecvt_in_all(const char* __first
, const char* __last
,
139 basic_string
<_CharT
, _Traits
, _Alloc
>& __outstr
,
140 const codecvt
<_CharT
, char, _State
>& __cvt
)
144 return __str_codecvt_in(__first
, __last
, __outstr
, __cvt
, __state
, __n
)
145 && (__n
== (__last
- __first
));
148 // Convert wide character string to narrow.
149 template<typename _CharT
, typename _Traits
, typename _Alloc
, typename _State
>
151 __str_codecvt_out(const _CharT
* __first
, const _CharT
* __last
,
152 basic_string
<char, _Traits
, _Alloc
>& __outstr
,
153 const codecvt
<_CharT
, char, _State
>& __cvt
,
154 _State
& __state
, size_t& __count
)
156 using _Codecvt
= codecvt
<_CharT
, char, _State
>;
158 = codecvt_base::result
159 (_Codecvt::*)(_State
&, const _CharT
*, const _CharT
*, const _CharT
*&,
160 char*, char*, char*&) const;
161 _ConvFn __fn
= &codecvt
<_CharT
, char, _State
>::out
;
162 return __do_str_codecvt(__first
, __last
, __outstr
, __cvt
, __state
,
166 // As above, but with no __count parameter
167 template<typename _CharT
, typename _Traits
, typename _Alloc
, typename _State
>
169 __str_codecvt_out(const _CharT
* __first
, const _CharT
* __last
,
170 basic_string
<char, _Traits
, _Alloc
>& __outstr
,
171 const codecvt
<_CharT
, char, _State
>& __cvt
)
175 return __str_codecvt_out(__first
, __last
, __outstr
, __cvt
, __state
, __n
);
178 // As above, but returns false for partial conversions
179 template<typename _CharT
, typename _Traits
, typename _Alloc
, typename _State
>
181 __str_codecvt_out_all(const _CharT
* __first
, const _CharT
* __last
,
182 basic_string
<char, _Traits
, _Alloc
>& __outstr
,
183 const codecvt
<_CharT
, char, _State
>& __cvt
)
187 return __str_codecvt_out(__first
, __last
, __outstr
, __cvt
, __state
, __n
)
188 && (__n
== (__last
- __first
));
191 #ifdef _GLIBCXX_USE_CHAR8_T
193 // Convert wide character string to narrow.
194 template<typename _CharT
, typename _Traits
, typename _Alloc
, typename _State
>
196 __str_codecvt_out(const _CharT
* __first
, const _CharT
* __last
,
197 basic_string
<char8_t
, _Traits
, _Alloc
>& __outstr
,
198 const codecvt
<_CharT
, char8_t
, _State
>& __cvt
,
199 _State
& __state
, size_t& __count
)
201 using _Codecvt
= codecvt
<_CharT
, char8_t
, _State
>;
203 = codecvt_base::result
204 (_Codecvt::*)(_State
&, const _CharT
*, const _CharT
*, const _CharT
*&,
205 char8_t
*, char8_t
*, char8_t
*&) const;
206 _ConvFn __fn
= &codecvt
<_CharT
, char8_t
, _State
>::out
;
207 return __do_str_codecvt(__first
, __last
, __outstr
, __cvt
, __state
,
211 template<typename _CharT
, typename _Traits
, typename _Alloc
, typename _State
>
213 __str_codecvt_out(const _CharT
* __first
, const _CharT
* __last
,
214 basic_string
<char8_t
, _Traits
, _Alloc
>& __outstr
,
215 const codecvt
<_CharT
, char8_t
, _State
>& __cvt
)
219 return __str_codecvt_out(__first
, __last
, __outstr
, __cvt
, __state
, __n
);
222 #endif // _GLIBCXX_USE_CHAR8_T
224 #ifdef _GLIBCXX_USE_WCHAR_T
226 _GLIBCXX_BEGIN_NAMESPACE_CXX11
228 /// String conversions
229 template<typename _Codecvt
, typename _Elem
= wchar_t,
230 typename _Wide_alloc
= allocator
<_Elem
>,
231 typename _Byte_alloc
= allocator
<char>>
232 class wstring_convert
235 typedef basic_string
<char, char_traits
<char>, _Byte_alloc
> byte_string
;
236 typedef basic_string
<_Elem
, char_traits
<_Elem
>, _Wide_alloc
> wide_string
;
237 typedef typename
_Codecvt::state_type state_type
;
238 typedef typename
wide_string::traits_type::int_type int_type
;
240 /// Default constructor.
241 wstring_convert() : _M_cvt(new _Codecvt()) { }
245 * @param __pcvt The facet to use for conversions.
247 * Takes ownership of @p __pcvt and will delete it in the destructor.
250 wstring_convert(_Codecvt
* __pcvt
) : _M_cvt(__pcvt
)
253 __throw_logic_error("wstring_convert");
256 /** Construct with an initial converstion state.
258 * @param __pcvt The facet to use for conversions.
259 * @param __state Initial conversion state.
261 * Takes ownership of @p __pcvt and will delete it in the destructor.
262 * The object's conversion state will persist between conversions.
264 wstring_convert(_Codecvt
* __pcvt
, state_type __state
)
265 : _M_cvt(__pcvt
), _M_state(__state
), _M_with_cvtstate(true)
268 __throw_logic_error("wstring_convert");
271 /** Construct with error strings.
273 * @param __byte_err A string to return on failed conversions.
274 * @param __wide_err A wide string to return on failed conversions.
277 wstring_convert(const byte_string
& __byte_err
,
278 const wide_string
& __wide_err
= wide_string())
279 : _M_cvt(new _Codecvt
),
280 _M_byte_err_string(__byte_err
), _M_wide_err_string(__wide_err
),
281 _M_with_strings(true)
284 __throw_logic_error("wstring_convert");
287 ~wstring_convert() = default;
289 // _GLIBCXX_RESOLVE_LIB_DEFECTS
290 // 2176. Special members for wstring_convert and wbuffer_convert
291 wstring_convert(const wstring_convert
&) = delete;
292 wstring_convert
& operator=(const wstring_convert
&) = delete;
294 /// @{ Convert from bytes.
296 from_bytes(char __byte
)
298 char __bytes
[2] = { __byte
};
299 return from_bytes(__bytes
, __bytes
+1);
303 from_bytes(const char* __ptr
)
304 { return from_bytes(__ptr
, __ptr
+char_traits
<char>::length(__ptr
)); }
307 from_bytes(const byte_string
& __str
)
309 auto __ptr
= __str
.data();
310 return from_bytes(__ptr
, __ptr
+ __str
.size());
314 from_bytes(const char* __first
, const char* __last
)
316 if (!_M_with_cvtstate
)
317 _M_state
= state_type();
318 wide_string __out
{ _M_wide_err_string
.get_allocator() };
319 if (__str_codecvt_in(__first
, __last
, __out
, *_M_cvt
, _M_state
,
323 return _M_wide_err_string
;
324 __throw_range_error("wstring_convert::from_bytes");
328 /// @{ Convert to bytes.
330 to_bytes(_Elem __wchar
)
332 _Elem __wchars
[2] = { __wchar
};
333 return to_bytes(__wchars
, __wchars
+1);
337 to_bytes(const _Elem
* __ptr
)
339 return to_bytes(__ptr
, __ptr
+wide_string::traits_type::length(__ptr
));
343 to_bytes(const wide_string
& __wstr
)
345 auto __ptr
= __wstr
.data();
346 return to_bytes(__ptr
, __ptr
+ __wstr
.size());
350 to_bytes(const _Elem
* __first
, const _Elem
* __last
)
352 if (!_M_with_cvtstate
)
353 _M_state
= state_type();
354 byte_string __out
{ _M_byte_err_string
.get_allocator() };
355 if (__str_codecvt_out(__first
, __last
, __out
, *_M_cvt
, _M_state
,
359 return _M_byte_err_string
;
360 __throw_range_error("wstring_convert::to_bytes");
364 // _GLIBCXX_RESOLVE_LIB_DEFECTS
365 // 2174. wstring_convert::converted() should be noexcept
366 /// The number of elements successfully converted in the last conversion.
367 size_t converted() const noexcept
{ return _M_count
; }
369 /// The final conversion state of the last conversion.
370 state_type
state() const { return _M_state
; }
373 unique_ptr
<_Codecvt
> _M_cvt
;
374 byte_string _M_byte_err_string
;
375 wide_string _M_wide_err_string
;
376 state_type _M_state
= state_type();
378 bool _M_with_cvtstate
= false;
379 bool _M_with_strings
= false;
382 _GLIBCXX_END_NAMESPACE_CXX11
384 /// Buffer conversions
385 template<typename _Codecvt
, typename _Elem
= wchar_t,
386 typename _Tr
= char_traits
<_Elem
>>
387 class wbuffer_convert
: public basic_streambuf
<_Elem
, _Tr
>
389 typedef basic_streambuf
<_Elem
, _Tr
> _Wide_streambuf
;
392 typedef typename
_Codecvt::state_type state_type
;
394 /// Default constructor.
395 wbuffer_convert() : wbuffer_convert(nullptr) { }
399 * @param __bytebuf The underlying byte stream buffer.
400 * @param __pcvt The facet to use for conversions.
401 * @param __state Initial conversion state.
403 * Takes ownership of @p __pcvt and will delete it in the destructor.
406 wbuffer_convert(streambuf
* __bytebuf
, _Codecvt
* __pcvt
= new _Codecvt
,
407 state_type __state
= state_type())
408 : _M_buf(__bytebuf
), _M_cvt(__pcvt
), _M_state(__state
)
411 __throw_logic_error("wbuffer_convert");
413 _M_always_noconv
= _M_cvt
->always_noconv();
417 this->setp(_M_put_area
, _M_put_area
+ _S_buffer_length
);
418 this->setg(_M_get_area
+ _S_putback_length
,
419 _M_get_area
+ _S_putback_length
,
420 _M_get_area
+ _S_putback_length
);
424 ~wbuffer_convert() = default;
426 // _GLIBCXX_RESOLVE_LIB_DEFECTS
427 // 2176. Special members for wstring_convert and wbuffer_convert
428 wbuffer_convert(const wbuffer_convert
&) = delete;
429 wbuffer_convert
& operator=(const wbuffer_convert
&) = delete;
431 streambuf
* rdbuf() const noexcept
{ return _M_buf
; }
434 rdbuf(streambuf
*__bytebuf
) noexcept
436 auto __prev
= _M_buf
;
441 /// The conversion state following the last conversion.
442 state_type
state() const noexcept
{ return _M_state
; }
447 { return _M_buf
&& _M_conv_put() && !_M_buf
->pubsync() ? 0 : -1; }
449 typename
_Wide_streambuf::int_type
450 overflow(typename
_Wide_streambuf::int_type __out
)
452 if (!_M_buf
|| !_M_conv_put())
454 else if (!_Tr::eq_int_type(__out
, _Tr::eof()))
455 return this->sputc(__out
);
456 return _Tr::not_eof(__out
);
459 typename
_Wide_streambuf::int_type
465 if (this->gptr() < this->egptr() || (_M_buf
&& _M_conv_get()))
466 return _Tr::to_int_type(*this->gptr());
472 xsputn(const typename
_Wide_streambuf::char_type
* __s
, streamsize __n
)
474 if (!_M_buf
|| __n
== 0)
476 streamsize __done
= 0;
479 auto __nn
= std::min
<streamsize
>(this->epptr() - this->pptr(),
481 _Tr::copy(this->pptr(), __s
+ __done
, __nn
);
484 } while (__done
< __n
&& _M_conv_put());
489 // fill the get area from converted contents of the byte stream buffer
493 const streamsize __pb1
= this->gptr() - this->eback();
494 const streamsize __pb2
= _S_putback_length
;
495 const streamsize __npb
= std::min(__pb1
, __pb2
);
497 _Tr::move(_M_get_area
+ _S_putback_length
- __npb
,
498 this->gptr() - __npb
, __npb
);
500 streamsize __nbytes
= sizeof(_M_get_buf
) - _M_unconv
;
501 __nbytes
= std::min(__nbytes
, _M_buf
->in_avail());
504 __nbytes
= _M_buf
->sgetn(_M_get_buf
+ _M_unconv
, __nbytes
);
507 __nbytes
+= _M_unconv
;
509 // convert _M_get_buf into _M_get_area
511 _Elem
* __outbuf
= _M_get_area
+ _S_putback_length
;
512 _Elem
* __outnext
= __outbuf
;
513 const char* __bnext
= _M_get_buf
;
515 codecvt_base::result __result
;
516 if (_M_always_noconv
)
517 __result
= codecvt_base::noconv
;
520 _Elem
* __outend
= _M_get_area
+ _S_buffer_length
;
522 __result
= _M_cvt
->in(_M_state
,
523 __bnext
, __bnext
+ __nbytes
, __bnext
,
524 __outbuf
, __outend
, __outnext
);
527 if (__result
== codecvt_base::noconv
)
529 // cast is safe because noconv means _Elem is same type as char
530 auto __get_buf
= reinterpret_cast<const _Elem
*>(_M_get_buf
);
531 _Tr::copy(__outbuf
, __get_buf
, __nbytes
);
536 if ((_M_unconv
= _M_get_buf
+ __nbytes
- __bnext
))
537 char_traits
<char>::move(_M_get_buf
, __bnext
, _M_unconv
);
539 this->setg(__outbuf
, __outbuf
, __outnext
);
541 return __result
!= codecvt_base::error
;
550 _M_put(const char* __p
, streamsize __n
)
552 if (_M_buf
->sputn(__p
, __n
) < __n
)
557 // convert the put area and write to the byte stream buffer
561 _Elem
* const __first
= this->pbase();
562 const _Elem
* const __last
= this->pptr();
563 const streamsize __pending
= __last
- __first
;
565 if (_M_always_noconv
)
566 return _M_put(__first
, __pending
);
568 char __outbuf
[2 * _S_buffer_length
];
570 const _Elem
* __next
= __first
;
571 const _Elem
* __start
;
575 char* __outnext
= __outbuf
;
576 char* const __outlast
= __outbuf
+ sizeof(__outbuf
);
577 auto __result
= _M_cvt
->out(_M_state
, __next
, __last
, __next
,
578 __outnext
, __outlast
, __outnext
);
579 if (__result
== codecvt_base::error
)
581 else if (__result
== codecvt_base::noconv
)
582 return _M_put(__next
, __pending
);
584 if (!_M_put(__outbuf
, __outnext
- __outbuf
))
587 while (__next
!= __last
&& __next
!= __start
);
589 if (__next
!= __last
)
590 _Tr::move(__first
, __next
, __last
- __next
);
592 this->pbump(__first
- __next
);
593 return __next
!= __first
;
597 unique_ptr
<_Codecvt
> _M_cvt
;
600 static const streamsize _S_buffer_length
= 32;
601 static const streamsize _S_putback_length
= 3;
602 _Elem _M_put_area
[_S_buffer_length
];
603 _Elem _M_get_area
[_S_buffer_length
];
604 streamsize _M_unconv
= 0;
605 char _M_get_buf
[_S_buffer_length
-_S_putback_length
];
606 bool _M_always_noconv
;
609 #endif // _GLIBCXX_USE_WCHAR_T
613 _GLIBCXX_END_NAMESPACE_VERSION
616 #endif // __cplusplus
618 #endif /* _LOCALE_CONV_H */