gcc/libstdc++-v3/include/bits/streambuf.tcc

247 lines
7.1 KiB
C++

// Stream buffer classes -*- C++ -*-
// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002
// 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// 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: 27.5 Stream buffers
//
#ifndef _CPP_BITS_STREAMBUF_TCC
#define _CPP_BITS_STREAMBUF_TCC 1
#pragma GCC system_header
namespace std
{
template<typename _CharT, typename _Traits>
typename basic_streambuf<_CharT, _Traits>::int_type
basic_streambuf<_CharT, _Traits>::
sbumpc()
{
int_type __ret;
if (_M_in_cur && _M_in_cur < _M_in_end)
{
char_type __c = *gptr();
_M_in_cur_move(1);
__ret = traits_type::to_int_type(__c);
}
else
__ret = this->uflow();
return __ret;
}
template<typename _CharT, typename _Traits>
typename basic_streambuf<_CharT, _Traits>::int_type
basic_streambuf<_CharT, _Traits>::
sputbackc(char_type __c)
{
int_type __ret;
bool __testpos = _M_in_cur && _M_in_beg < _M_in_cur;
bool __testne = _M_in_cur && !traits_type::eq(__c, this->gptr()[-1]);
if (!__testpos || __testne)
__ret = pbackfail(traits_type::to_int_type(__c));
else
{
_M_in_cur_move(-1);
__ret = traits_type::to_int_type(*this->gptr());
}
return __ret;
}
template<typename _CharT, typename _Traits>
typename basic_streambuf<_CharT, _Traits>::int_type
basic_streambuf<_CharT, _Traits>::
sungetc()
{
int_type __ret;
if (_M_in_cur && _M_in_beg < _M_in_cur)
{
_M_in_cur_move(-1);
__ret = traits_type::to_int_type(*_M_in_cur);
}
else
__ret = this->pbackfail();
return __ret;
}
// Don't test against _M_buf + _M_buf_size, because _M_buf reflects
// allocated space, and on certain (rare but entirely legal)
// situations, there will be no allocated space yet the internal
// buffers will still be valid. (This happens if setp is used to set
// the internal buffer to say some externally-allocated sequence.)
template<typename _CharT, typename _Traits>
typename basic_streambuf<_CharT, _Traits>::int_type
basic_streambuf<_CharT, _Traits>::
sputc(char_type __c)
{
int_type __ret;
if (_M_out_buf_size())
{
*_M_out_cur = __c;
_M_out_cur_move(1);
__ret = traits_type::to_int_type(__c);
}
else
__ret = this->overflow(traits_type::to_int_type(__c));
return __ret;
}
template<typename _CharT, typename _Traits>
streamsize
basic_streambuf<_CharT, _Traits>::
xsgetn(char_type* __s, streamsize __n)
{
streamsize __ret = 0;
while (__ret < __n)
{
size_t __buf_len = _M_in_end - _M_in_cur;
if (__buf_len > 0)
{
size_t __remaining = __n - __ret;
size_t __len = min(__buf_len, __remaining);
traits_type::copy(__s, _M_in_cur, __len);
__ret += __len;
__s += __len;
_M_in_cur_move(__len);
}
if (__ret < __n)
{
int_type __c = this->uflow();
if (__c != traits_type::eof())
{
traits_type::assign(*__s++, traits_type::to_char_type(__c));
++__ret;
}
else
break;
}
}
return __ret;
}
// Don't test against _M_buf + _M_buf_size, because _M_buf reflects
// allocated space, and on certain (rare but entirely legal)
// situations, there will be no allocated space yet the internal
// buffers will still be valid. (This happens if setp is used to set
// the internal buffer to say some externally-allocated sequence.)
template<typename _CharT, typename _Traits>
streamsize
basic_streambuf<_CharT, _Traits>::
xsputn(const char_type* __s, streamsize __n)
{
streamsize __ret = 0;
while (__ret < __n)
{
off_type __buf_len = _M_out_buf_size();
if (__buf_len > 0)
{
off_type __remaining = __n - __ret;
off_type __len = min(__buf_len, __remaining);
traits_type::copy(_M_out_cur, __s, __len);
__ret += __len;
__s += __len;
_M_out_cur_move(__len);
}
if (__ret < __n)
{
int_type __c = this->overflow(traits_type::to_int_type(*__s));
if (__c != traits_type::eof())
{
++__ret;
++__s;
}
else
break;
}
}
return __ret;
}
// Conceivably, this could be used to implement buffer-to-buffer
// copies, if this was ever desired in an un-ambiguous way by the
// standard. If so, then checks for __ios being zero would be
// necessary.
template<typename _CharT, typename _Traits>
streamsize
__copy_streambufs(basic_ios<_CharT, _Traits>& __ios,
basic_streambuf<_CharT, _Traits>* __sbin,
basic_streambuf<_CharT, _Traits>* __sbout)
{
typedef typename _Traits::int_type int_type;
streamsize __ret = 0;
streamsize __bufsize = __sbin->in_avail();
streamsize __xtrct;
bool __testput = __sbout->_M_mode & ios_base::out;
try
{
while (__testput && __bufsize != -1)
{
__xtrct = __sbout->sputn(__sbin->gptr(), __bufsize);
__ret += __xtrct;
__sbin->_M_in_cur_move(__xtrct);
if (__xtrct == __bufsize)
{
if (__sbin->sgetc() == _Traits::eof())
break;
__bufsize = __sbin->in_avail();
}
else
break;
}
}
catch(exception& __fail)
{
__ios.setstate(ios_base::failbit);
if ((__ios.exceptions() & ios_base::failbit) != 0)
__throw_exception_again;
}
return __ret;
}
// Inhibit implicit instantiations for required instantiations,
// which are defined via explicit instantiations elsewhere.
// NB: This syntax is a GNU extension.
extern template class basic_streambuf<char>;
extern template
streamsize
__copy_streambufs(basic_ios<char>&, basic_streambuf<char>*,
basic_streambuf<char>*);
extern template class basic_streambuf<wchar_t>;
extern template
streamsize
__copy_streambufs(basic_ios<wchar_t>&, basic_streambuf<wchar_t>*,
basic_streambuf<wchar_t>*);
} // namespace std
#endif