219 lines
6.1 KiB
C++
219 lines
6.1 KiB
C++
// std::codecvt implementation details, generic version -*- C++ -*-
|
|
|
|
// Copyright (C) 2002, 2005 Free Software Foundation, Inc.
|
|
//
|
|
// This file is part of the GNU ISO C++ Library. This library is free
|
|
// software; you can redistribute it and/or modify it under the
|
|
// terms of the GNU General Public License as published by the
|
|
// Free Software Foundation; either version 2, or (at your option)
|
|
// any later version.
|
|
|
|
// This library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
|
|
// You should have received a copy of the GNU General Public License along
|
|
// with this library; see the file COPYING. If not, write to the Free
|
|
// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
|
|
// USA.
|
|
|
|
// As a special exception, you may use this file as part of a free software
|
|
// library without restriction. Specifically, if other files instantiate
|
|
// templates or use macros or inline functions from this file, or you compile
|
|
// this file and link it with other files to produce an executable, this
|
|
// file does not by itself cause the resulting executable to be covered by
|
|
// the GNU General Public License. This exception does not however
|
|
// invalidate any other reasons why the executable file might be covered by
|
|
// the GNU General Public License.
|
|
|
|
//
|
|
// ISO C++ 14882: 22.2.1.5 - Template class codecvt
|
|
//
|
|
|
|
// Written by Benjamin Kosnik <bkoz@redhat.com>
|
|
|
|
#include <locale>
|
|
|
|
_GLIBCXX_BEGIN_NAMESPACE(std)
|
|
|
|
// Specializations.
|
|
#ifdef _GLIBCXX_USE_WCHAR_T
|
|
codecvt_base::result
|
|
codecvt<wchar_t, char, mbstate_t>::
|
|
do_out(state_type& __state, const intern_type* __from,
|
|
const intern_type* __from_end, const intern_type*& __from_next,
|
|
extern_type* __to, extern_type* __to_end,
|
|
extern_type*& __to_next) const
|
|
{
|
|
result __ret = ok;
|
|
// The conversion must be done using a temporary destination buffer
|
|
// since it is not possible to pass the size of the buffer to wcrtomb
|
|
state_type __tmp_state(__state);
|
|
|
|
// The conversion must be done by calling wcrtomb in a loop rather
|
|
// than using wcsrtombs because wcsrtombs assumes that the input is
|
|
// zero-terminated.
|
|
|
|
// Either we can upper bound the total number of external characters to
|
|
// something smaller than __to_end - __to or the conversion must be done
|
|
// using a temporary destination buffer since it is not possible to
|
|
// pass the size of the buffer to wcrtomb
|
|
if (MB_CUR_MAX * (__from_end - __from) - (__to_end - __to) <= 0)
|
|
while (__from < __from_end)
|
|
{
|
|
const size_t __conv = wcrtomb(__to, *__from, &__tmp_state);
|
|
if (__conv == static_cast<size_t>(-1))
|
|
{
|
|
__ret = error;
|
|
break;
|
|
}
|
|
__state = __tmp_state;
|
|
__to += __conv;
|
|
__from++;
|
|
}
|
|
else
|
|
{
|
|
extern_type __buf[MB_LEN_MAX];
|
|
while (__from < __from_end && __to < __to_end)
|
|
{
|
|
const size_t __conv = wcrtomb(__buf, *__from, &__tmp_state);
|
|
if (__conv == static_cast<size_t>(-1))
|
|
{
|
|
__ret = error;
|
|
break;
|
|
}
|
|
else if (__conv > static_cast<size_t>(__to_end - __to))
|
|
{
|
|
__ret = partial;
|
|
break;
|
|
}
|
|
|
|
memcpy(__to, __buf, __conv);
|
|
__state = __tmp_state;
|
|
__to += __conv;
|
|
__from++;
|
|
}
|
|
}
|
|
|
|
if (__ret == ok && __from < __from_end)
|
|
__ret = partial;
|
|
|
|
__from_next = __from;
|
|
__to_next = __to;
|
|
return __ret;
|
|
}
|
|
|
|
codecvt_base::result
|
|
codecvt<wchar_t, char, mbstate_t>::
|
|
do_in(state_type& __state, const extern_type* __from,
|
|
const extern_type* __from_end, const extern_type*& __from_next,
|
|
intern_type* __to, intern_type* __to_end,
|
|
intern_type*& __to_next) const
|
|
{
|
|
result __ret = ok;
|
|
// This temporary state object is neccessary so __state won't be modified
|
|
// if [__from, __from_end) is a partial multibyte character.
|
|
state_type __tmp_state(__state);
|
|
|
|
// Conversion must be done by calling mbrtowc in a loop rather than
|
|
// by calling mbsrtowcs because mbsrtowcs assumes that the input
|
|
// sequence is zero-terminated.
|
|
while (__from < __from_end && __to < __to_end)
|
|
{
|
|
size_t __conv = mbrtowc(__to, __from, __from_end - __from,
|
|
&__tmp_state);
|
|
if (__conv == static_cast<size_t>(-1))
|
|
{
|
|
__ret = error;
|
|
break;
|
|
}
|
|
else if (__conv == static_cast<size_t>(-2))
|
|
{
|
|
// It is unclear what to return in this case (see DR 382).
|
|
__ret = partial;
|
|
break;
|
|
}
|
|
else if (__conv == 0)
|
|
{
|
|
// XXX Probably wrong for stateful encodings
|
|
__conv = 1;
|
|
*__to = L'\0';
|
|
}
|
|
|
|
__state = __tmp_state;
|
|
__to++;
|
|
__from += __conv;
|
|
}
|
|
|
|
// It is not clear that __from < __from_end implies __ret != ok
|
|
// (see DR 382).
|
|
if (__ret == ok && __from < __from_end)
|
|
__ret = partial;
|
|
|
|
__from_next = __from;
|
|
__to_next = __to;
|
|
return __ret;
|
|
}
|
|
|
|
int
|
|
codecvt<wchar_t, char, mbstate_t>::
|
|
do_encoding() const throw()
|
|
{
|
|
// XXX This implementation assumes that the encoding is
|
|
// stateless and is either single-byte or variable-width.
|
|
int __ret = 0;
|
|
if (MB_CUR_MAX == 1)
|
|
__ret = 1;
|
|
return __ret;
|
|
}
|
|
|
|
int
|
|
codecvt<wchar_t, char, mbstate_t>::
|
|
do_max_length() const throw()
|
|
{
|
|
// XXX Probably wrong for stateful encodings.
|
|
int __ret = MB_CUR_MAX;
|
|
return __ret;
|
|
}
|
|
|
|
int
|
|
codecvt<wchar_t, char, mbstate_t>::
|
|
do_length(state_type& __state, const extern_type* __from,
|
|
const extern_type* __end, size_t __max) const
|
|
{
|
|
int __ret = 0;
|
|
state_type __tmp_state(__state);
|
|
|
|
while (__from < __end && __max)
|
|
{
|
|
size_t __conv = mbrtowc(NULL, __from, __end - __from, &__tmp_state);
|
|
if (__conv == static_cast<size_t>(-1))
|
|
{
|
|
// Invalid source character
|
|
break;
|
|
}
|
|
else if (__conv == static_cast<size_t>(-2))
|
|
{
|
|
// Remainder of input does not form a complete destination
|
|
// character.
|
|
break;
|
|
}
|
|
else if (__conv == 0)
|
|
{
|
|
// XXX Probably wrong for stateful encodings
|
|
__conv = 1;
|
|
}
|
|
|
|
__state = __tmp_state;
|
|
__from += __conv;
|
|
__ret += __conv;
|
|
__max--;
|
|
}
|
|
|
|
return __ret;
|
|
}
|
|
#endif
|
|
|
|
_GLIBCXX_END_NAMESPACE
|