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

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// String based streams -*- 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: 27.7 String-based streams
//
#ifndef _CPP_BITS_SSTREAM_TCC
#define _CPP_BITS_SSTREAM_TCC 1
#include <bits/std_sstream.h>
namespace std {
template <class _CharT, class _Traits, class _Alloc>
basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
basic_stringbuf<_CharT, _Traits, _Alloc>::
pbackfail(int_type __c)
{
int_type __retval = traits_type::eof();
bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());
bool __testpos = _M_in_cur && _M_in_beg < _M_in_cur;
// 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 && __testpos
&& traits_type::eq(traits_type::to_char_type(__c), this->gptr()[-1]))
{
--_M_in_cur;
__retval = __c;
}
else if (!__testeof && __testpos)
{
--_M_in_cur;
*_M_in_cur = traits_type::to_char_type(__c);
__retval = __c;
}
else if (__testeof && __testpos)
{
--_M_in_cur;
__retval = traits_type::not_eof(__c);
}
return __retval;
}
template <class _CharT, class _Traits, class _Alloc>
basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
basic_stringbuf<_CharT, _Traits, _Alloc>::
overflow(int_type __c)
{
int_type __retval = traits_type::eof();
bool __testeof = traits_type::eq_int_type(__c, __retval);
bool __testwrite = _M_out_cur < _M_buf + _M_buf_size;
bool __testout = _M_mode & ios_base::out;
// Try to append __c into output sequence in one of two ways.
// Order these tests done in is unspecified by the standard.
if (__testout)
{
if (!__testeof)
{
// NB: Start ostringstream buffers at 1024 bytes. This
// is an experimental value (pronounced "arbitrary" in
// some of the hipper english-speaking countries), and
// can be changed to suite particular needs.
__size_type __len = max(_M_buf_size, static_cast<int_type>(512));
__len *= 2;
if (__testwrite)
__retval = this->sputc(__c);
else if (__len <= _M_string.max_size())
{
// Force-allocate, re-sync.
_M_string = this->str();
_M_string.reserve(__len);
_M_buf_size = static_cast<int_type>(__len);
_M_really_sync(_M_in_cur - _M_in_beg,
_M_out_cur - _M_out_beg);
*_M_out_cur = traits_type::to_char_type(__c);
_M_buf_bump(1);
__retval = __c;
}
}
else
__retval = traits_type::not_eof(__c);
}
return __retval;
}
template <class _CharT, class _Traits, class _Alloc>
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 __retval = pos_type(off_type(-1));
bool __testin = __mode & ios_base::in && _M_mode & ios_base::in;
bool __testout = __mode & ios_base::out && _M_mode & ios_base::out;
bool __testboth = __testin && __testout && __way != ios_base::cur;
if (_M_buf_size && ((__testin != __testout) || __testboth))
{
char_type* __beg = _M_buf;
char_type* __curi = NULL;
char_type* __curo = NULL;
char_type* __endi = NULL;
char_type* __endo = NULL;
if (__testin)
{
__curi = this->gptr();
__endi = this->egptr();
}
if (__testout)
{
__curo = this->pptr();
__endo = this->epptr();
}
off_type __newoffi = 0;
off_type __newoffo = 0;
if (__way == ios_base::cur)
{
__newoffi = __curi - __beg;
__newoffo = __curo - __beg;
}
else if (__way == ios_base::end)
{
__newoffi = __endi - __beg;
__newoffo = __endo - __beg;
}
if (__testin
&& __newoffi + __off >= 0 && __endi - __beg >= __newoffi + __off)
{
_M_in_cur = __beg + __newoffi + __off;
__retval = pos_type(__newoffi);
}
if (__testout
&& __newoffo + __off >= 0 && __endo - __beg >= __newoffo + __off)
{
_M_buf_bump(__newoffo + __off - (_M_out_cur - __beg));
__retval = pos_type(__newoffo);
}
}
return __retval;
}
template <class _CharT, class _Traits, class _Alloc>
basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
basic_stringbuf<_CharT, _Traits, _Alloc>::
seekpos(pos_type __sp, ios_base::openmode __mode)
{
pos_type __retval = pos_type(off_type(-1));
off_type __pos = __sp._M_position();
char_type* __beg = NULL;
char_type* __end = NULL;
bool __testin = __mode & ios_base::in && _M_mode & ios_base::in;
bool __testout = __mode & ios_base::out && _M_mode & ios_base::out;
if (__testin)
{
__beg = this->eback();
__end = this->egptr();
}
if (__testout)
{
__beg = this->pbase();
__end = _M_buf + _M_buf_size;
}
if (0 <= __pos && __pos <= __end - __beg)
{
// Need to set both of these if applicable
if (__testin)
_M_in_cur = _M_in_beg + __pos;
if (__testout)
_M_buf_bump((__pos) - (_M_out_cur - __beg));
__retval = pos_type(off_type(__pos));
}
return __retval;
}
} // namespace std
#endif /* _CPP_BITS_SSTREAM_TCC */