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

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// Stream buffer classes -*- C++ -*-
// Copyright (C) 1997-1999 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
namespace std {
template<typename _CharT, typename _Traits>
basic_streambuf<_CharT, _Traits>::int_type
basic_streambuf<_CharT, _Traits>::
sbumpc()
{
int_type __retval;
if (_M_in_cur && _M_in_cur < _M_in_end)
{
char_type __c = *gptr();
++_M_in_cur;
if (_M_buf_unified && _M_mode & ios_base::out)
++_M_out_cur;
__retval = traits_type::to_int_type(__c);
}
else
__retval = this->uflow();
return __retval;
}
template<typename _CharT, typename _Traits>
basic_streambuf<_CharT, _Traits>::int_type
basic_streambuf<_CharT, _Traits>::
sputbackc(char_type __c)
{
int_type __retval;
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)
__retval = pbackfail(traits_type::to_int_type(__c));
else
{
--_M_in_cur;
if (_M_buf_unified && _M_mode & ios_base::out)
--_M_out_cur;
__retval = traits_type::to_int_type(*this->gptr());
}
return __retval;
}
template<typename _CharT, typename _Traits>
basic_streambuf<_CharT, _Traits>::int_type
basic_streambuf<_CharT, _Traits>::
sungetc()
{
int_type __retval;
if (_M_in_cur && _M_in_beg < _M_in_cur)
{
--_M_in_cur;
if (_M_buf_unified && _M_mode & ios_base::out)
--_M_out_cur;
__retval = traits_type::to_int_type(*_M_in_cur);
}
else
__retval = this->pbackfail();
return __retval;
}
// 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>
basic_streambuf<_CharT, _Traits>::int_type
basic_streambuf<_CharT, _Traits>::
sputc(char_type __c)
{
int_type __retval;
if (_M_out_cur && _M_out_cur < _M_out_beg + _M_buf_size)
{
*_M_out_cur = __c;
_M_buf_bump(1);
__retval = traits_type::to_int_type(__c);
}
else
__retval = this->overflow(traits_type::to_int_type(__c));
return __retval;
}
template<typename _CharT, typename _Traits>
streamsize
basic_streambuf<_CharT, _Traits>::
xsgetn(char_type* __s, streamsize __n)
{
bool __testout = _M_mode & ios_base::out;
streamsize __retval = 0;
if (__n)
{
while (__retval < __n)
{
if (_M_in_cur < _M_in_end)
{
size_t __len;
if (_M_in_cur + __n - __retval <= _M_in_end)
__len = __n - __retval;
else
__len = _M_in_end - _M_in_cur;
traits_type::copy(__s, _M_in_cur, __len);
__retval += __len;
__s += __len;
_M_in_cur += __len;
if (_M_buf_unified && __testout)
_M_out_cur += __len;
}
if (__retval != __n)
{
if (this->uflow() != traits_type::eof())
++__retval;
else
break;
}
}
}
return __retval;
}
// 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 __retval = 0;
if (__n)
{
while (__retval < __n)
{
bool __testput = _M_out_cur < _M_out_beg + _M_buf_size;
bool __testout = _M_mode & ios_base::out;
if (!(__testput && __testout))
{
char_type __c = *__s;
char_type __overfc = this->overflow(__c);
if (__c == __overfc)
{
++__retval;
++__s;
}
else
break;
}
if (__retval != __n)
{
size_t __len;
if (_M_out_cur + __n - __retval <= _M_out_beg + _M_buf_size)
__len = __n - __retval;
else
__len = _M_out_beg + _M_buf_size - _M_out_cur;
traits_type::copy(_M_out_cur, __s, __len);
__retval += __len;
__s += __len;
_M_buf_bump(__len);
}
}
}
return __retval;
}
// 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>
static streamsize
_S_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 __retval = 0;
streamsize __bufsize = __sbin->in_avail();
streamsize __xtrct;
bool __testout = __sbin->_M_mode & ios_base::out;
bool __testput = __sbout->_M_mode & ios_base::out;
try {
while (__testput && __bufsize != -1)
{
__xtrct = __sbout->sputn(__sbin->gptr(), __bufsize);
__retval += __xtrct;
__sbin->_M_in_cur += __xtrct;
if (__testout && __sbin->_M_buf_unified)
__sbin->_M_out_cur += __xtrct;
if (__xtrct == __bufsize)
{
int_type __c = __sbin->sgetc();
if (__c == _Traits::eof())
{
__ios.setstate(ios_base::eofbit);
break;
}
}
else
break;
}
}
catch(exception& __fail) {
if ((__ios.exceptions() & ios_base::failbit) != 0)
throw;
}
return __retval;
}
} // namespace std
#endif // _CPP_BITS_STREAMBUF_TCC