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// wstring_convert implementation -*- C++ -*-
// Copyright (C) 2015-2018 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 3, 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.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file bits/locale_conv.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{locale}
*/
#ifndef _LOCALE_CONV_H
#define _LOCALE_CONV_H 1
#if __cplusplus < 201103L
# include <bits/c++0x_warning.h>
#else
#include <streambuf>
#include <bits/stringfwd.h>
#include <bits/allocator.h>
#include <bits/codecvt.h>
#include <bits/unique_ptr.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @addtogroup locales
* @{
*/
template<typename _OutStr, typename _InChar, typename _Codecvt,
typename _State, typename _Fn>
bool
__do_str_codecvt(const _InChar* __first, const _InChar* __last,
_OutStr& __outstr, const _Codecvt& __cvt, _State& __state,
size_t& __count, _Fn __fn)
{
if (__first == __last)
{
__outstr.clear();
__count = 0;
return true;
}
size_t __outchars = 0;
auto __next = __first;
const auto __maxlen = __cvt.max_length() + 1;
codecvt_base::result __result;
do
{
__outstr.resize(__outstr.size() + (__last - __next) * __maxlen);
auto __outnext = &__outstr.front() + __outchars;
auto const __outlast = &__outstr.back() + 1;
__result = (__cvt.*__fn)(__state, __next, __last, __next,
__outnext, __outlast, __outnext);
__outchars = __outnext - &__outstr.front();
}
while (__result == codecvt_base::partial && __next != __last
&& (__outstr.size() - __outchars) < __maxlen);
if (__result == codecvt_base::error)
{
__count = __next - __first;
return false;
}
if (__result == codecvt_base::noconv)
{
__outstr.assign(__first, __last);
__count = __last - __first;
}
else
{
__outstr.resize(__outchars);
__count = __next - __first;
}
return true;
}
// Convert narrow character string to wide.
template<typename _CharT, typename _Traits, typename _Alloc, typename _State>
inline bool
__str_codecvt_in(const char* __first, const char* __last,
basic_string<_CharT, _Traits, _Alloc>& __outstr,
const codecvt<_CharT, char, _State>& __cvt,
_State& __state, size_t& __count)
{
using _Codecvt = codecvt<_CharT, char, _State>;
using _ConvFn
= codecvt_base::result
(_Codecvt::*)(_State&, const char*, const char*, const char*&,
_CharT*, _CharT*, _CharT*&) const;
_ConvFn __fn = &codecvt<_CharT, char, _State>::in;
return __do_str_codecvt(__first, __last, __outstr, __cvt, __state,
__count, __fn);
}
template<typename _CharT, typename _Traits, typename _Alloc, typename _State>
inline bool
__str_codecvt_in(const char* __first, const char* __last,
basic_string<_CharT, _Traits, _Alloc>& __outstr,
const codecvt<_CharT, char, _State>& __cvt)
{
_State __state = {};
size_t __n;
return __str_codecvt_in(__first, __last, __outstr, __cvt, __state, __n);
}
// Convert wide character string to narrow.
template<typename _CharT, typename _Traits, typename _Alloc, typename _State>
inline bool
__str_codecvt_out(const _CharT* __first, const _CharT* __last,
basic_string<char, _Traits, _Alloc>& __outstr,
const codecvt<_CharT, char, _State>& __cvt,
_State& __state, size_t& __count)
{
using _Codecvt = codecvt<_CharT, char, _State>;
using _ConvFn
= codecvt_base::result
(_Codecvt::*)(_State&, const _CharT*, const _CharT*, const _CharT*&,
char*, char*, char*&) const;
_ConvFn __fn = &codecvt<_CharT, char, _State>::out;
return __do_str_codecvt(__first, __last, __outstr, __cvt, __state,
__count, __fn);
}
template<typename _CharT, typename _Traits, typename _Alloc, typename _State>
inline bool
__str_codecvt_out(const _CharT* __first, const _CharT* __last,
basic_string<char, _Traits, _Alloc>& __outstr,
const codecvt<_CharT, char, _State>& __cvt)
{
_State __state = {};
size_t __n;
return __str_codecvt_out(__first, __last, __outstr, __cvt, __state, __n);
}
#ifdef _GLIBCXX_USE_WCHAR_T
_GLIBCXX_BEGIN_NAMESPACE_CXX11
/// String conversions
template<typename _Codecvt, typename _Elem = wchar_t,
typename _Wide_alloc = allocator<_Elem>,
typename _Byte_alloc = allocator<char>>
class wstring_convert
{
public:
typedef basic_string<char, char_traits<char>, _Byte_alloc> byte_string;
typedef basic_string<_Elem, char_traits<_Elem>, _Wide_alloc> wide_string;
typedef typename _Codecvt::state_type state_type;
typedef typename wide_string::traits_type::int_type int_type;
/** Default constructor.
*
* @param __pcvt The facet to use for conversions.
*
* Takes ownership of @p __pcvt and will delete it in the destructor.
*/
explicit
wstring_convert(_Codecvt* __pcvt = new _Codecvt()) : _M_cvt(__pcvt)
{
if (!_M_cvt)
__throw_logic_error("wstring_convert");
}
/** Construct with an initial converstion state.
*
* @param __pcvt The facet to use for conversions.
* @param __state Initial conversion state.
*
* Takes ownership of @p __pcvt and will delete it in the destructor.
* The object's conversion state will persist between conversions.
*/
wstring_convert(_Codecvt* __pcvt, state_type __state)
: _M_cvt(__pcvt), _M_state(__state), _M_with_cvtstate(true)
{
if (!_M_cvt)
__throw_logic_error("wstring_convert");
}
/** Construct with error strings.
*
* @param __byte_err A string to return on failed conversions.
* @param __wide_err A wide string to return on failed conversions.
*/
explicit
wstring_convert(const byte_string& __byte_err,
const wide_string& __wide_err = wide_string())
: _M_cvt(new _Codecvt),
_M_byte_err_string(__byte_err), _M_wide_err_string(__wide_err),
_M_with_strings(true)
{
if (!_M_cvt)
__throw_logic_error("wstring_convert");
}
~wstring_convert() = default;
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2176. Special members for wstring_convert and wbuffer_convert
wstring_convert(const wstring_convert&) = delete;
wstring_convert& operator=(const wstring_convert&) = delete;
/// @{ Convert from bytes.
wide_string
from_bytes(char __byte)
{
char __bytes[2] = { __byte };
return from_bytes(__bytes, __bytes+1);
}
wide_string
from_bytes(const char* __ptr)
{ return from_bytes(__ptr, __ptr+char_traits<char>::length(__ptr)); }
wide_string
from_bytes(const byte_string& __str)
{
auto __ptr = __str.data();
return from_bytes(__ptr, __ptr + __str.size());
}
wide_string
from_bytes(const char* __first, const char* __last)
{
if (!_M_with_cvtstate)
_M_state = state_type();
wide_string __out{ _M_wide_err_string.get_allocator() };
if (__str_codecvt_in(__first, __last, __out, *_M_cvt, _M_state,
_M_count))
return __out;
if (_M_with_strings)
return _M_wide_err_string;
__throw_range_error("wstring_convert::from_bytes");
}
/// @}
/// @{ Convert to bytes.
byte_string
to_bytes(_Elem __wchar)
{
_Elem __wchars[2] = { __wchar };
return to_bytes(__wchars, __wchars+1);
}
byte_string
to_bytes(const _Elem* __ptr)
{
return to_bytes(__ptr, __ptr+wide_string::traits_type::length(__ptr));
}
byte_string
to_bytes(const wide_string& __wstr)
{
auto __ptr = __wstr.data();
return to_bytes(__ptr, __ptr + __wstr.size());
}
byte_string
to_bytes(const _Elem* __first, const _Elem* __last)
{
if (!_M_with_cvtstate)
_M_state = state_type();
byte_string __out{ _M_byte_err_string.get_allocator() };
if (__str_codecvt_out(__first, __last, __out, *_M_cvt, _M_state,
_M_count))
return __out;
if (_M_with_strings)
return _M_byte_err_string;
__throw_range_error("wstring_convert::to_bytes");
}
/// @}
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2174. wstring_convert::converted() should be noexcept
/// The number of elements successfully converted in the last conversion.
size_t converted() const noexcept { return _M_count; }
/// The final conversion state of the last conversion.
state_type state() const { return _M_state; }
private:
unique_ptr<_Codecvt> _M_cvt;
byte_string _M_byte_err_string;
wide_string _M_wide_err_string;
state_type _M_state = state_type();
size_t _M_count = 0;
bool _M_with_cvtstate = false;
bool _M_with_strings = false;
};
_GLIBCXX_END_NAMESPACE_CXX11
/// Buffer conversions
template<typename _Codecvt, typename _Elem = wchar_t,
typename _Tr = char_traits<_Elem>>
class wbuffer_convert : public basic_streambuf<_Elem, _Tr>
{
typedef basic_streambuf<_Elem, _Tr> _Wide_streambuf;
public:
typedef typename _Codecvt::state_type state_type;
/** Default constructor.
*
* @param __bytebuf The underlying byte stream buffer.
* @param __pcvt The facet to use for conversions.
* @param __state Initial conversion state.
*
* Takes ownership of @p __pcvt and will delete it in the destructor.
*/
explicit
wbuffer_convert(streambuf* __bytebuf = 0, _Codecvt* __pcvt = new _Codecvt,
state_type __state = state_type())
: _M_buf(__bytebuf), _M_cvt(__pcvt), _M_state(__state)
{
if (!_M_cvt)
__throw_logic_error("wbuffer_convert");
_M_always_noconv = _M_cvt->always_noconv();
if (_M_buf)
{
this->setp(_M_put_area, _M_put_area + _S_buffer_length);
this->setg(_M_get_area + _S_putback_length,
_M_get_area + _S_putback_length,
_M_get_area + _S_putback_length);
}
}
~wbuffer_convert() = default;
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2176. Special members for wstring_convert and wbuffer_convert
wbuffer_convert(const wbuffer_convert&) = delete;
wbuffer_convert& operator=(const wbuffer_convert&) = delete;
streambuf* rdbuf() const noexcept { return _M_buf; }
streambuf*
rdbuf(streambuf *__bytebuf) noexcept
{
auto __prev = _M_buf;
_M_buf = __bytebuf;
return __prev;
}
/// The conversion state following the last conversion.
state_type state() const noexcept { return _M_state; }
protected:
int
sync()
{ return _M_buf && _M_conv_put() && !_M_buf->pubsync() ? 0 : -1; }
typename _Wide_streambuf::int_type
overflow(typename _Wide_streambuf::int_type __out)
{
if (!_M_buf || !_M_conv_put())
return _Tr::eof();
else if (!_Tr::eq_int_type(__out, _Tr::eof()))
return this->sputc(__out);
return _Tr::not_eof(__out);
}
typename _Wide_streambuf::int_type
underflow()
{
if (!_M_buf)
return _Tr::eof();
if (this->gptr() < this->egptr() || (_M_buf && _M_conv_get()))
return _Tr::to_int_type(*this->gptr());
else
return _Tr::eof();
}
streamsize
xsputn(const typename _Wide_streambuf::char_type* __s, streamsize __n)
{
if (!_M_buf || __n == 0)
return 0;
streamsize __done = 0;
do
{
auto __nn = std::min<streamsize>(this->epptr() - this->pptr(),
__n - __done);
_Tr::copy(this->pptr(), __s + __done, __nn);
this->pbump(__nn);
__done += __nn;
} while (__done < __n && _M_conv_put());
return __done;
}
private:
// fill the get area from converted contents of the byte stream buffer
bool
_M_conv_get()
{
const streamsize __pb1 = this->gptr() - this->eback();
const streamsize __pb2 = _S_putback_length;
const streamsize __npb = std::min(__pb1, __pb2);
_Tr::move(_M_get_area + _S_putback_length - __npb,
this->gptr() - __npb, __npb);
streamsize __nbytes = sizeof(_M_get_buf) - _M_unconv;
__nbytes = std::min(__nbytes, _M_buf->in_avail());
if (__nbytes < 1)
__nbytes = 1;
__nbytes = _M_buf->sgetn(_M_get_buf + _M_unconv, __nbytes);
if (__nbytes < 1)
return false;
__nbytes += _M_unconv;
// convert _M_get_buf into _M_get_area
_Elem* __outbuf = _M_get_area + _S_putback_length;
_Elem* __outnext = __outbuf;
const char* __bnext = _M_get_buf;
codecvt_base::result __result;
if (_M_always_noconv)
__result = codecvt_base::noconv;
else
{
_Elem* __outend = _M_get_area + _S_buffer_length;
__result = _M_cvt->in(_M_state,
__bnext, __bnext + __nbytes, __bnext,
__outbuf, __outend, __outnext);
}
if (__result == codecvt_base::noconv)
{
// cast is safe because noconv means _Elem is same type as char
auto __get_buf = reinterpret_cast<const _Elem*>(_M_get_buf);
_Tr::copy(__outbuf, __get_buf, __nbytes);
_M_unconv = 0;
return true;
}
if ((_M_unconv = _M_get_buf + __nbytes - __bnext))
char_traits<char>::move(_M_get_buf, __bnext, _M_unconv);
this->setg(__outbuf, __outbuf, __outnext);
return __result != codecvt_base::error;
}
// unused
bool
_M_put(...)
{ return false; }
bool
_M_put(const char* __p, streamsize __n)
{
if (_M_buf->sputn(__p, __n) < __n)
return false;
return true;
}
// convert the put area and write to the byte stream buffer
bool
_M_conv_put()
{
_Elem* const __first = this->pbase();
const _Elem* const __last = this->pptr();
const streamsize __pending = __last - __first;
if (_M_always_noconv)
return _M_put(__first, __pending);
char __outbuf[2 * _S_buffer_length];
const _Elem* __next = __first;
const _Elem* __start;
do
{
__start = __next;
char* __outnext = __outbuf;
char* const __outlast = __outbuf + sizeof(__outbuf);
auto __result = _M_cvt->out(_M_state, __next, __last, __next,
__outnext, __outlast, __outnext);
if (__result == codecvt_base::error)
return false;
else if (__result == codecvt_base::noconv)
return _M_put(__next, __pending);
if (!_M_put(__outbuf, __outnext - __outbuf))
return false;
}
while (__next != __last && __next != __start);
if (__next != __last)
_Tr::move(__first, __next, __last - __next);
this->pbump(__first - __next);
return __next != __first;
}
streambuf* _M_buf;
unique_ptr<_Codecvt> _M_cvt;
state_type _M_state;
static const streamsize _S_buffer_length = 32;
static const streamsize _S_putback_length = 3;
_Elem _M_put_area[_S_buffer_length];
_Elem _M_get_area[_S_buffer_length];
streamsize _M_unconv = 0;
char _M_get_buf[_S_buffer_length-_S_putback_length];
bool _M_always_noconv;
};
#endif // _GLIBCXX_USE_WCHAR_T
/// @} group locales
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif // __cplusplus
#endif /* _LOCALE_CONV_H */
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