gcc/libstdc++-v3/include/bits/sstream.tcc
2004-02-08 05:46:42 +01:00

224 lines
7.6 KiB
C++

// String based streams -*- C++ -*-
// Copyright (C) 1997, 1998, 1999, 2001, 2002, 2003
// 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: 27.7 String-based streams
//
#ifndef _SSTREAM_TCC
#define _SSTREAM_TCC 1
#pragma GCC system_header
#include <sstream>
namespace std
{
template <class _CharT, class _Traits, class _Alloc>
typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
basic_stringbuf<_CharT, _Traits, _Alloc>::
pbackfail(int_type __c)
{
int_type __ret = traits_type::eof();
const bool __testeof = traits_type::eq_int_type(__c, __ret);
if (this->eback() < this->gptr())
{
const bool __testeq = traits_type::eq(traits_type::to_char_type(__c),
this->gptr()[-1]);
this->gbump(-1);
// Try to put back __c into input sequence in one of three ways.
// Order these tests done in is unspecified by the standard.
if (!__testeof && __testeq)
__ret = __c;
else if (__testeof)
__ret = traits_type::not_eof(__c);
else
{
*this->gptr() = traits_type::to_char_type(__c);
__ret = __c;
}
}
return __ret;
}
template <class _CharT, class _Traits, class _Alloc>
typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
basic_stringbuf<_CharT, _Traits, _Alloc>::
overflow(int_type __c)
{
const bool __testout = this->_M_mode & ios_base::out;
if (__builtin_expect(!__testout, false))
return traits_type::eof();
const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());
if (__builtin_expect(__testeof, false))
return traits_type::not_eof(__c);
// NB: Start ostringstream buffers at 512 chars. This is an
// experimental value (pronounced "arbitrary" in some of the
// hipper english-speaking countries), and can be changed to
// suit particular needs.
const __size_type __len = std::max(__size_type(_M_string.capacity() + 1),
__size_type(512));
const bool __testput = this->pptr() < this->epptr();
if (__builtin_expect(!__testput && __len > _M_string.max_size(), false))
return traits_type::eof();
// Try to append __c into output sequence in one of two ways.
// Order these tests done in is unspecified by the standard.
if (!__testput)
{
// In virtue of DR 169 (TC) we are allowed to grow more than
// one char. That's easy to implement thanks to the exponential
// growth policy builtin into basic_string.
__string_type __tmp;
__tmp.reserve(__len);
__tmp.assign(_M_string.data(), this->epptr() - this->pbase());
_M_string.swap(__tmp);
_M_sync(const_cast<char_type*>(_M_string.data()),
this->gptr() - this->eback(), this->pptr() - this->pbase());
}
return this->sputc(traits_type::to_char_type(__c));
}
template <class _CharT, class _Traits, class _Alloc>
typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
basic_stringbuf<_CharT, _Traits, _Alloc>::
underflow()
{
int_type __ret = traits_type::eof();
const bool __testin = this->_M_mode & ios_base::in;
if (__testin)
{
// Update egptr() to match the actual string end.
_M_update_egptr();
if (this->gptr() < this->egptr())
__ret = traits_type::to_int_type(*this->gptr());
}
return __ret;
}
template <class _CharT, class _Traits, class _Alloc>
typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
basic_stringbuf<_CharT, _Traits, _Alloc>::
seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
{
pos_type __ret = pos_type(off_type(-1));
bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
const bool __testboth = __testin && __testout && __way != ios_base::cur;
__testin &= !(__mode & ios_base::out);
__testout &= !(__mode & ios_base::in);
if (_M_string.capacity() && (__testin || __testout || __testboth))
{
char_type* __beg = __testin ? this->eback() : this->pbase();
_M_update_egptr();
off_type __newoffi = 0;
off_type __newoffo = 0;
if (__way == ios_base::cur)
{
__newoffi = this->gptr() - __beg;
__newoffo = this->pptr() - __beg;
}
else if (__way == ios_base::end)
__newoffo = __newoffi = this->egptr() - __beg;
if ((__testin || __testboth)
&& __newoffi + __off >= 0
&& this->egptr() - __beg >= __newoffi + __off)
{
this->gbump((__beg + __newoffi + __off) - this->gptr());
__ret = pos_type(__newoffi);
}
if ((__testout || __testboth)
&& __newoffo + __off >= 0
&& this->egptr() - __beg >= __newoffo + __off)
{
this->pbump((__beg + __newoffo + __off) - this->pptr());
__ret = pos_type(__newoffo);
}
}
return __ret;
}
template <class _CharT, class _Traits, class _Alloc>
typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
basic_stringbuf<_CharT, _Traits, _Alloc>::
seekpos(pos_type __sp, ios_base::openmode __mode)
{
pos_type __ret = pos_type(off_type(-1));
if (_M_string.capacity())
{
off_type __pos (__sp);
const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
char_type* __beg = __testin ? this->eback() : this->pbase();
_M_update_egptr();
const bool __testpos = 0 <= __pos
&& __pos <= this->egptr() - __beg;
if ((__testin || __testout) && __testpos)
{
if (__testin)
this->gbump((__beg + __pos) - this->gptr());
if (__testout)
this->pbump((__beg + __pos) - this->pptr());
__ret = pos_type(off_type(__pos));
}
}
return __ret;
}
// Inhibit implicit instantiations for required instantiations,
// which are defined via explicit instantiations elsewhere.
// NB: This syntax is a GNU extension.
#if _GLIBCXX_EXTERN_TEMPLATE
extern template class basic_stringbuf<char>;
extern template class basic_istringstream<char>;
extern template class basic_ostringstream<char>;
extern template class basic_stringstream<char>;
#ifdef _GLIBCXX_USE_WCHAR_T
extern template class basic_stringbuf<wchar_t>;
extern template class basic_istringstream<wchar_t>;
extern template class basic_ostringstream<wchar_t>;
extern template class basic_stringstream<wchar_t>;
#endif
#endif
} // namespace std
#endif