[thirdparty/gcc.git] / libstdc++-v3 / include / bits / fstream.tcc

// File based streams -*- 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: 27.8  File-based streams
//

#ifndef _CPP_BITS_FSTREAM_TCC
#define _CPP_BITS_FSTREAM_TCC 1

#pragma GCC system_header

namespace std
{
  template<typename _CharT, typename _Traits>
    void
    basic_filebuf<_CharT, _Traits>::
    _M_allocate_internal_buffer()
    {
      if (!_M_buf && _M_buf_size_opt)
	{
	  _M_buf_size = _M_buf_size_opt;

	  // Allocate internal buffer.
	  _M_buf = new char_type[_M_buf_size]; 
	  _M_buf_allocated = true;
	}
    }

  // Both close and setbuf need to deallocate internal buffers, if it exists.
  template<typename _CharT, typename _Traits>
    void
    basic_filebuf<_CharT, _Traits>::
    _M_destroy_internal_buffer()
    {
      if (_M_buf_allocated)
	{
	  delete [] _M_buf;
	  _M_buf = NULL;
	  _M_buf_allocated = false;
	  this->setg(NULL, NULL, NULL);
	  this->setp(NULL, NULL);
	}
    }

  template<typename _CharT, typename _Traits>
    basic_filebuf<_CharT, _Traits>::
    basic_filebuf() : __streambuf_type(), _M_file(&_M_lock), 
    _M_state_cur(__state_type()), _M_state_beg(__state_type()), 
    _M_buf_allocated(false), _M_last_overflowed(false)
    { _M_buf_unified = true; }

  template<typename _CharT, typename _Traits>
    typename basic_filebuf<_CharT, _Traits>::__filebuf_type* 
    basic_filebuf<_CharT, _Traits>::
    open(const char* __s, ios_base::openmode __mode)
    {
      __filebuf_type *__ret = NULL;
      if (!this->is_open())
	{
	  _M_file.open(__s, __mode);
	  if (this->is_open())
	    {
	      _M_allocate_internal_buffer();
	      _M_mode = __mode;

	      // Setup initial position of buffer.
	      _M_set_indeterminate();

	      // Set input buffer to something real.
	      // NB: Must open in non-blocking way to do this, or must
	      // set the initial position in a different manner than
	      // using underflow.
 	      if (__mode & ios_base::in && _M_buf_allocated)
 		this->underflow();
	      
	      if ((__mode & ios_base::ate)
		  && this->seekoff(0, ios_base::end, __mode) < 0)
		this->close();

	      __ret = this;
	    }
	}
      return __ret;
    }

  template<typename _CharT, typename _Traits>
    typename basic_filebuf<_CharT, _Traits>::__filebuf_type* 
    basic_filebuf<_CharT, _Traits>::
    close()
    {
      __filebuf_type *__ret = NULL;
      if (this->is_open())
	{
	  const int_type __eof = traits_type::eof();
	  bool __testput = _M_out_cur && _M_out_beg < _M_out_end;
	  if (__testput 
	      && traits_type::eq_int_type(_M_really_overflow(__eof), __eof))
	    return __ret;

	  // NB: Do this here so that re-opened filebufs will be cool...
	  _M_mode = ios_base::openmode(0);
	  _M_destroy_internal_buffer();
	  _M_pback_destroy();
	  
#if 0
	  // XXX not done
	  if (_M_last_overflowed)
	    {
	      _M_output_unshift();
	      _M_really_overflow(__eof);
	    }
#endif

	  if (_M_file.close())
	    __ret = this;
	}

      _M_last_overflowed = false;	
      return __ret;
    }

  template<typename _CharT, typename _Traits>
    streamsize 
    basic_filebuf<_CharT, _Traits>::
    showmanyc()
    {
      streamsize __ret = -1;
      bool __testin = _M_mode & ios_base::in;

      if (__testin && this->is_open())
	__ret = _M_in_end - _M_in_cur;
      _M_last_overflowed = false;	
      return __ret;
    }
  
  template<typename _CharT, typename _Traits>
    typename basic_filebuf<_CharT, _Traits>::int_type 
    basic_filebuf<_CharT, _Traits>::
    pbackfail(int_type __i)
    {
      int_type __ret = traits_type::eof();
      bool __testin = _M_mode & ios_base::in;

      if (__testin)
	{
	  bool __testpb = _M_in_beg < _M_in_cur;
	  char_type __c = traits_type::to_char_type(__i);
	  bool __testeof = traits_type::eq_int_type(__i, __ret);

	  if (__testpb)
	    {
	      bool __testout = _M_mode & ios_base::out;
	      bool __testeq = traits_type::eq(__c, this->gptr()[-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)
		{
		  --_M_in_cur;
		  if (__testout)
		    --_M_out_cur;
		  __ret = __i;
		}
	      else if (__testeof)
		{
		  --_M_in_cur;
		  if (__testout)
		    --_M_out_cur;
		  __ret = traits_type::not_eof(__i);
		}
	      else if (!__testeof)
		{
		  --_M_in_cur;
		  if (__testout)
		    --_M_out_cur;
		  _M_pback_create();
		  *_M_in_cur = __c; 
		  __ret = __i;
		}
	    }
	  else
	    {	 
 	      // At the beginning of the buffer, need to make a
	      // putback position available.
	      this->seekoff(-1, ios_base::cur);
	      this->underflow();
 	      if (!__testeof)
 		{
		  if (!traits_type::eq(__c, *_M_in_cur))
		    {
		      _M_pback_create();
		      *_M_in_cur = __c;
		    }
 		  __ret = __i;
 		}
 	      else
 		__ret = traits_type::not_eof(__i);
 	    }
	}
      _M_last_overflowed = false;	
      return __ret;
    }

  template<typename _CharT, typename _Traits>
    typename basic_filebuf<_CharT, _Traits>::int_type 
    basic_filebuf<_CharT, _Traits>::
    overflow(int_type __c)
    {
      int_type __ret = traits_type::eof();
      bool __testput = _M_out_cur && _M_out_cur < _M_buf + _M_buf_size;
      bool __testout = _M_mode & ios_base::out;
      
      if (__testout)
	{
	  if (__testput)
	    {
	      *_M_out_cur = traits_type::to_char_type(__c);
	      _M_out_cur_move(1);
	      __ret = traits_type::not_eof(__c);
	    }
	  else 
	    __ret = this->_M_really_overflow(__c);
	}

      _M_last_overflowed = false;    // Set in _M_really_overflow, below.
      return __ret;
    }
  
  template<typename _CharT, typename _Traits>
    void
    basic_filebuf<_CharT, _Traits>::
    _M_convert_to_external(_CharT* __ibuf, streamsize __ilen,
			   streamsize& __elen, streamsize& __plen)
    {
      const locale __loc = this->getloc();
      const __codecvt_type& __cvt = use_facet<__codecvt_type>(__loc);
      
      if (__cvt.always_noconv() && __ilen)
	{
	  __elen += _M_file.xsputn(reinterpret_cast<char*>(__ibuf), __ilen);
	  __plen += __ilen;
	}
      else
	{
	  // Worst-case number of external bytes needed.
	  int __ext_multiplier = __cvt.encoding();
	  if (__ext_multiplier ==  -1 || __ext_multiplier == 0)
	    __ext_multiplier = sizeof(char_type);
	  streamsize __blen = __ilen * __ext_multiplier;
	  char* __buf = static_cast<char*>(__builtin_alloca(__blen));
	  char* __bend;
	  const char_type* __iend;
	  __res_type __r = __cvt.out(_M_state_cur, __ibuf, __ibuf + __ilen, 
		 		     __iend, __buf, __buf + __blen, __bend);
	  // Result == ok, partial, noconv
	  if (__r != codecvt_base::error)
	    __blen = __bend - __buf;
	  // Result == error
	  else 
	    __blen = 0;
	  
	  if (__blen)
	    {
	      __elen += _M_file.xsputn(__buf, __blen);
	      __plen += __blen;
	    }

	  // Try once more for partial conversions.
	  if (__r == codecvt_base::partial)
	    {
	      const char_type* __iresume = __iend;
	      streamsize __rlen = _M_out_end - __iend;
	      __r = __cvt.out(_M_state_cur, __iresume, __iresume + __rlen, 
			      __iend, __buf, __buf + __blen, __bend);
	      if (__r != codecvt_base::error)
		__rlen = __bend - __buf;
	      else 
		__rlen = 0;
	      if (__rlen)
		{
		  __elen += _M_file.xsputn(__buf, __rlen);
		  __plen += __rlen;
		}
	    }
	}
    }

  template<typename _CharT, typename _Traits>
    typename basic_filebuf<_CharT, _Traits>::int_type 
    basic_filebuf<_CharT, _Traits>::
    _M_really_overflow(int_type __c)
    {
      int_type __ret = traits_type::eof();
      bool __testput = _M_out_cur && _M_out_beg < _M_out_end;
      bool __testunbuffered = _M_file.is_open() && !_M_buf_size_opt;

      if (__testput || __testunbuffered)
	{
	  // Sizes of external and pending output.
	  streamsize __elen = 0;
	  streamsize __plen = 0;

	  // Need to restore current position. The position of the external
	  // byte sequence (_M_file) corresponds to _M_filepos, and we need
	  // to move it to _M_out_beg for the write.
	  if (_M_filepos && _M_filepos != _M_out_beg)
	    {
	      off_type __off = _M_out_beg - _M_filepos;
	      _M_file.seekoff(__off, ios_base::cur);
	    }

	  // Convert internal buffer to external representation, output.
	  // NB: In the unbuffered case, no internal buffer exists. 
	  if (!__testunbuffered)
	    _M_convert_to_external(_M_out_beg,  _M_out_end - _M_out_beg, 
				   __elen, __plen);

	  // Convert pending sequence to external representation, output.
	  // If eof, then just attempt sync.
	  if (!traits_type::eq_int_type(__c, traits_type::eof()))
	    {
	      char_type __pending = traits_type::to_char_type(__c);
	      _M_convert_to_external(&__pending, 1, __elen, __plen);

	      // User code must flush when switching modes (thus don't sync).
	      if (__elen == __plen)
		{
		  _M_set_indeterminate();
		  __ret = traits_type::not_eof(__c);
		}
	    }
	  else if (!_M_file.sync())
	    {
	      _M_set_indeterminate();
	      __ret = traits_type::not_eof(__c);
	    }
	}	      
      _M_last_overflowed = true;	
      return __ret;
    }

  template<typename _CharT, typename _Traits>
    typename basic_filebuf<_CharT, _Traits>::__streambuf_type* 
    basic_filebuf<_CharT, _Traits>::
    setbuf(char_type* __s, streamsize __n)
    {
      if (!this->is_open() && __s == 0 && __n == 0)
	_M_buf_size_opt = 0;
      else if (__s && __n)
	{
	  // This is implementation-defined behavior, and assumes
	  // that an external char_type array of length (__s + __n)
	  // exists and has been pre-allocated. If this is not the
	  // case, things will quickly blow up.
	  // Step 1: Destroy the current internal array.
	  _M_destroy_internal_buffer();
	  
	  // Step 2: Use the external array.
	  _M_buf = __s;
	  _M_buf_size_opt = _M_buf_size = __n;
	  _M_set_indeterminate();
	}
      _M_last_overflowed = false;	
      return this; 
    }
  
  template<typename _CharT, typename _Traits>
    typename basic_filebuf<_CharT, _Traits>::pos_type
    basic_filebuf<_CharT, _Traits>::
    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 & _M_mode & __mode) != 0;
      bool __testout = (ios_base::out & _M_mode & __mode) != 0;

      // Should probably do has_facet checks here.
      int __width = use_facet<__codecvt_type>(_M_buf_locale).encoding();
      if (__width < 0)
	__width = 0;
      bool __testfail = __off != 0 && __width <= 0;
      
      if (this->is_open() && !__testfail && (__testin || __testout)) 
	{
	  // Ditch any pback buffers to avoid confusion.
	  _M_pback_destroy();

	  if (__way != ios_base::cur || __off != 0)
	    { 
	      off_type __computed_off = __width * __off;
	      
	      bool __testget = _M_in_cur && _M_in_beg < _M_in_end;
	      bool __testput = _M_out_cur && _M_out_beg < _M_out_end;
	      // Sync the internal and external streams.
	      // out
	      if (__testput || _M_last_overflowed)
		{
		  // Part one: update the output sequence.
		  this->sync();
		  // Part two: output unshift sequence.
		  _M_output_unshift();
		}
	      //in
	      else if (__testget && __way == ios_base::cur)
		__computed_off += _M_in_cur - _M_filepos;
	  
	      __ret = _M_file.seekoff(__computed_off, __way, __mode);
	      _M_set_indeterminate();
	    }
	  // NB: Need to do this in case _M_file in indeterminate
	  // state, ie _M_file._offset == -1
	  else
	    {
	      __ret = _M_file.seekoff(__off, ios_base::cur, __mode);
	      __ret += std::max(_M_out_cur, _M_in_cur) - _M_filepos;
	    }
	}
      _M_last_overflowed = false;	
      return __ret;
    }

  template<typename _CharT, typename _Traits>
    typename basic_filebuf<_CharT, _Traits>::pos_type
    basic_filebuf<_CharT, _Traits>::
    seekpos(pos_type __pos, ios_base::openmode __mode)
    {
#ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS
// 171. Strange seekpos() semantics due to joint position
      return this->seekoff(off_type(__pos), ios_base::beg, __mode);
#endif
    }

  template<typename _CharT, typename _Traits>
    void 
    basic_filebuf<_CharT, _Traits>::
    _M_output_unshift()
    { }

  template<typename _CharT, typename _Traits>
    void
    basic_filebuf<_CharT, _Traits>::
    imbue(const locale& __loc)
    {
      bool __testbeg = gptr() == eback() && pptr() == pbase();

      if (__testbeg && _M_buf_locale != __loc)
	{
	  _M_buf_locale = __loc;
	  _M_buf_locale_init = true;
	}

      // NB this may require the reconversion of previously
      // converted chars. This in turn may cause the reconstruction
      // of the original file. YIKES!!
      // XXX The part in the above comment is not done.
      _M_last_overflowed = false;	
    }

  // Inhibit implicit instantiations for required instantiations,
  // which are defined via explicit instantiations elsewhere.  
  // NB:  This syntax is a GNU extension.
  extern template class basic_filebuf<char>;
  extern template class basic_ifstream<char>;
  extern template class basic_ofstream<char>;
  extern template class basic_fstream<char>;

#ifdef _GLIBCPP_USE_WCHAR_T
  extern template class basic_filebuf<wchar_t>;
  extern template class basic_ifstream<wchar_t>;
  extern template class basic_ofstream<wchar_t>;
  extern template class basic_fstream<wchar_t>;
#endif
} // namespace std

#endif
Commit	Line	Data
725dc051 BK	1	// File based streams -- C++ --
725dc051 BK	2
e6705174 BK	3	// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002
e6705174 BK	4	// Free Software Foundation, Inc.
725dc051 BK	5	//
	6	// This file is part of the GNU ISO C++ Library. This library is free
	7	// software; you can redistribute it and/or modify it under the
	8	// terms of the GNU General Public License as published by the
	9	// Free Software Foundation; either version 2, or (at your option)
	10	// any later version.
	11
	12	// This library is distributed in the hope that it will be useful,
	13	// but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	// GNU General Public License for more details.
	16
	17	// You should have received a copy of the GNU General Public License along
	18	// with this library; see the file COPYING. If not, write to the Free
	19	// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
	20	// USA.
	21
	22	// As a special exception, you may use this file as part of a free software
	23	// library without restriction. Specifically, if other files instantiate
	24	// templates or use macros or inline functions from this file, or you compile
	25	// this file and link it with other files to produce an executable, this
	26	// file does not by itself cause the resulting executable to be covered by
	27	// the GNU General Public License. This exception does not however
	28	// invalidate any other reasons why the executable file might be covered by
	29	// the GNU General Public License.
	30
	31	//
	32	// ISO C++ 14882: 27.8 File-based streams
	33	//
	34
	35	#ifndef _CPP_BITS_FSTREAM_TCC
	36	#define _CPP_BITS_FSTREAM_TCC 1
	37
3b794528 BK	38	#pragma GCC system_header
3b794528 BK	39
725dc051 BK	40	namespace std
725dc051 BK	41	{
725dc051 BK	42	template<typename _CharT, typename _Traits>
	43	void
	44	basic_filebuf<_CharT, _Traits>::
990101f9	45	_M_allocate_internal_buffer()
725dc051	46	{
990101f9	47	if (!_M_buf && _M_buf_size_opt)
13187a45 BK	48	{
13187a45 BK	49	_M_buf_size = _M_buf_size_opt;
990101f9	50
5cdd50a5	51	// Allocate internal buffer.
540f5c9b	52	_M_buf = new char_type[_M_buf_size];
5cdd50a5	53	_M_buf_allocated = true;
990101f9 BK	54	}
	55	}
	56
	57	// Both close and setbuf need to deallocate internal buffers, if it exists.
	58	template<typename _CharT, typename _Traits>
	59	void
	60	basic_filebuf<_CharT, _Traits>::
	61	_M_destroy_internal_buffer()
	62	{
	63	if (_M_buf_allocated)
	64	{
	65	delete [] _M_buf;
	66	_M_buf = NULL;
	67	_M_buf_allocated = false;
	68	this->setg(NULL, NULL, NULL);
	69	this->setp(NULL, NULL);
	70	}
725dc051 BK	71	}
	72
	73	template<typename _CharT, typename _Traits>
	74	basic_filebuf<_CharT, _Traits>::
5cdd50a5 BK	75	basic_filebuf() : __streambuf_type(), _M_file(&_M_lock),
	76	_M_state_cur(__state_type()), _M_state_beg(__state_type()),
	77	_M_buf_allocated(false), _M_last_overflowed(false)
d3a193e3	78	{ _M_buf_unified = true; }
725dc051	79
725dc051	80	template<typename _CharT, typename _Traits>
31bfa177	81	typename basic_filebuf<_CharT, _Traits>::__filebuf_type*
725dc051 BK	82	basic_filebuf<_CharT, _Traits>::
	83	open(const char* __s, ios_base::openmode __mode)
	84	{
	85	__filebuf_type *__ret = NULL;
	86	if (!this->is_open())
	87	{
d3a193e3	88	_M_file.open(__s, __mode);
13187a45	89	if (this->is_open())
725dc051	90	{
990101f9	91	_M_allocate_internal_buffer();
725dc051	92	_M_mode = __mode;
6eeb7d7a BK	93
6eeb7d7a BK	94	// Setup initial position of buffer.
725dc051	95	_M_set_indeterminate();
6e52332e	96
6eeb7d7a BK	97	// Set input buffer to something real.
	98	// NB: Must open in non-blocking way to do this, or must
	99	// set the initial position in a different manner than
	100	// using underflow.
	101	if (__mode & ios_base::in && _M_buf_allocated)
	102	this->underflow();
	103
b7737230	104	if ((__mode & ios_base::ate)
725dc051 BK	105	&& this->seekoff(0, ios_base::end, __mode) < 0)
725dc051 BK	106	this->close();
6eeb7d7a	107
725dc051 BK	108	__ret = this;
	109	}
	110	}
	111	return __ret;
	112	}
	113
	114	template<typename _CharT, typename _Traits>
31bfa177	115	typename basic_filebuf<_CharT, _Traits>::__filebuf_type*
725dc051 BK	116	basic_filebuf<_CharT, _Traits>::
	117	close()
	118	{
	119	__filebuf_type *__ret = NULL;
	120	if (this->is_open())
	121	{
e6705174	122	const int_type __eof = traits_type::eof();
725dc051	123	bool __testput = _M_out_cur && _M_out_beg < _M_out_end;
f13a69ec BK	124	if (__testput
f13a69ec BK	125	&& traits_type::eq_int_type(_M_really_overflow(__eof), __eof))
e6705174	126	return __ret;
725dc051	127
e6705174 BK	128	// NB: Do this here so that re-opened filebufs will be cool...
	129	_M_mode = ios_base::openmode(0);
	130	_M_destroy_internal_buffer();
e6705174	131	_M_pback_destroy();
e6705174	132
725dc051 BK	133	#if 0
	134	// XXX not done
	135	if (_M_last_overflowed)
	136	{
	137	_M_output_unshift();
e6705174	138	_M_really_overflow(__eof);
725dc051 BK	139	}
725dc051 BK	140	#endif
725dc051	141
d3a193e3 BK	142	if (_M_file.close())
d3a193e3 BK	143	__ret = this;
725dc051	144	}
d3a193e3	145
725dc051 BK	146	_M_last_overflowed = false;
	147	return __ret;
	148	}
	149
	150	template<typename _CharT, typename _Traits>
	151	streamsize
	152	basic_filebuf<_CharT, _Traits>::
	153	showmanyc()
	154	{
	155	streamsize __ret = -1;
	156	bool __testin = _M_mode & ios_base::in;
	157
9fbcb61a	158	if (__testin && this->is_open())
6e52332e	159	__ret = _M_in_end - _M_in_cur;
725dc051 BK	160	_M_last_overflowed = false;
	161	return __ret;
	162	}
725dc051 BK	163
725dc051 BK	164	template<typename _CharT, typename _Traits>
31bfa177	165	typename basic_filebuf<_CharT, _Traits>::int_type
725dc051 BK	166	basic_filebuf<_CharT, _Traits>::
	167	pbackfail(int_type __i)
	168	{
	169	int_type __ret = traits_type::eof();
	170	bool __testin = _M_mode & ios_base::in;
	171
	172	if (__testin)
	173	{
	174	bool __testpb = _M_in_beg < _M_in_cur;
	175	char_type __c = traits_type::to_char_type(__i);
	176	bool __testeof = traits_type::eq_int_type(__i, __ret);
	177
	178	if (__testpb)
	179	{
	180	bool __testout = _M_mode & ios_base::out;
	181	bool __testeq = traits_type::eq(__c, this->gptr()[-1]);
	182
	183	// Try to put back __c into input sequence in one of three ways.
	184	// Order these tests done in is unspecified by the standard.
	185	if (!__testeof && __testeq)
	186	{
	187	--_M_in_cur;
	188	if (__testout)
	189	--_M_out_cur;
	190	__ret = __i;
	191	}
	192	else if (__testeof)
	193	{
	194	--_M_in_cur;
	195	if (__testout)
	196	--_M_out_cur;
	197	__ret = traits_type::not_eof(__i);
	198	}
	199	else if (!__testeof)
	200	{
	201	--_M_in_cur;
	202	if (__testout)
	203	--_M_out_cur;
	204	_M_pback_create();
	205	*_M_in_cur = __c;
	206	__ret = __i;
	207	}
	208	}
	209	else
	210	{
	211	// At the beginning of the buffer, need to make a
	212	// putback position available.
	213	this->seekoff(-1, ios_base::cur);
	214	this->underflow();
	215	if (!__testeof)
	216	{
	217	if (!traits_type::eq(__c, *_M_in_cur))
	218	{
	219	_M_pback_create();
	220	*_M_in_cur = __c;
	221	}
	222	__ret = __i;
	223	}
	224	else
	225	__ret = traits_type::not_eof(__i);
	226	}
	227	}
	228	_M_last_overflowed = false;
	229	return __ret;
230	}
231
232	template<typename _CharT, typename _Traits>
31bfa177	233	typename basic_filebuf<_CharT, _Traits>::int_type
725dc051 BK	234	basic_filebuf<_CharT, _Traits>::
	235	overflow(int_type __c)
	236	{
	237	int_type __ret = traits_type::eof();
5fa9abc3	238	bool __testput = _M_out_cur && _M_out_cur < _M_buf + _M_buf_size;
725dc051 BK	239	bool __testout = _M_mode & ios_base::out;
	240
	241	if (__testout)
	242	{
5fa9abc3	243	if (__testput)
725dc051 BK	244	{
	245	*_M_out_cur = traits_type::to_char_type(__c);
	246	_M_out_cur_move(1);
	247	__ret = traits_type::not_eof(__c);
	248	}
	249	else
	250	__ret = this->_M_really_overflow(__c);
	251	}
	252
	253	_M_last_overflowed = false; // Set in _M_really_overflow, below.
	254	return __ret;
	255	}
	256
07814743 BK	257	template<typename _CharT, typename _Traits>
	258	void
	259	basic_filebuf<_CharT, _Traits>::
	260	_M_convert_to_external(_CharT* __ibuf, streamsize __ilen,
	261	streamsize& __elen, streamsize& __plen)
	262	{
07814743 BK	263	const locale __loc = this->getloc();
	264	const __codecvt_type& __cvt = use_facet<__codecvt_type>(__loc);
	265
	266	if (__cvt.always_noconv() && __ilen)
	267	{
d3a193e3	268	__elen += _M_file.xsputn(reinterpret_cast<char*>(__ibuf), __ilen);
07814743 BK	269	__plen += __ilen;
	270	}
	271	else
	272	{
	273	// Worst-case number of external bytes needed.
	274	int __ext_multiplier = __cvt.encoding();
	275	if (__ext_multiplier == -1 \|\| __ext_multiplier == 0)
	276	__ext_multiplier = sizeof(char_type);
	277	streamsize __blen = __ilen * __ext_multiplier;
	278	char* __buf = static_cast<char*>(__builtin_alloca(__blen));
	279	char* __bend;
	280	const char_type* __iend;
	281	__res_type __r = __cvt.out(_M_state_cur, __ibuf, __ibuf + __ilen,
	282	__iend, __buf, __buf + __blen, __bend);
	283	// Result == ok, partial, noconv
	284	if (__r != codecvt_base::error)
	285	__blen = __bend - __buf;
	286	// Result == error
	287	else
	288	__blen = 0;
	289
	290	if (__blen)
	291	{
d3a193e3	292	__elen += _M_file.xsputn(__buf, __blen);
07814743 BK	293	__plen += __blen;
	294	}
	295
	296	// Try once more for partial conversions.
	297	if (__r == codecvt_base::partial)
	298	{
	299	const char_type* __iresume = __iend;
	300	streamsize __rlen = _M_out_end - __iend;
	301	__r = __cvt.out(_M_state_cur, __iresume, __iresume + __rlen,
	302	__iend, __buf, __buf + __blen, __bend);
	303	if (__r != codecvt_base::error)
	304	__rlen = __bend - __buf;
	305	else
	306	__rlen = 0;
	307	if (__rlen)
	308	{
d3a193e3	309	__elen += _M_file.xsputn(__buf, __rlen);
07814743 BK	310	__plen += __rlen;
	311	}
	312	}
	313	}
	314	}
	315
725dc051	316	template<typename _CharT, typename _Traits>
31bfa177	317	typename basic_filebuf<_CharT, _Traits>::int_type
725dc051 BK	318	basic_filebuf<_CharT, _Traits>::
	319	_M_really_overflow(int_type __c)
	320	{
	321	int_type __ret = traits_type::eof();
	322	bool __testput = _M_out_cur && _M_out_beg < _M_out_end;
6e52332e	323	bool __testunbuffered = _M_file.is_open() && !_M_buf_size_opt;
5fa9abc3 BK	324
5fa9abc3 BK	325	if (__testput \|\| __testunbuffered)
725dc051	326	{
07814743 BK	327	// Sizes of external and pending output.
	328	streamsize __elen = 0;
	329	streamsize __plen = 0;
	330
5066927d JM	331	// Need to restore current position. The position of the external
	332	// byte sequence (_M_file) corresponds to _M_filepos, and we need
	333	// to move it to _M_out_beg for the write.
	334	if (_M_filepos && _M_filepos != _M_out_beg)
	335	{
	336	off_type __off = _M_out_beg - _M_filepos;
	337	_M_file.seekoff(__off, ios_base::cur);
	338	}
	339
07814743 BK	340	// Convert internal buffer to external representation, output.
	341	// NB: In the unbuffered case, no internal buffer exists.
	342	if (!__testunbuffered)
	343	_M_convert_to_external(_M_out_beg, _M_out_end - _M_out_beg,
	344	__elen, __plen);
	345
	346	// Convert pending sequence to external representation, output.
9385d9cb	347	// If eof, then just attempt sync.
07814743	348	if (!traits_type::eq_int_type(__c, traits_type::eof()))
725dc051	349	{
07814743 BK	350	char_type __pending = traits_type::to_char_type(__c);
07814743 BK	351	_M_convert_to_external(&__pending, 1, __elen, __plen);
5fa9abc3	352
9385d9cb LR	353	// User code must flush when switching modes (thus don't sync).
	354	if (__elen == __plen)
	355	{
	356	_M_set_indeterminate();
	357	__ret = traits_type::not_eof(__c);
	358	}
	359	}
	360	else if (!_M_file.sync())
e6705174 BK	361	{
	362	_M_set_indeterminate();
	363	__ret = traits_type::not_eof(__c);
	364	}
725dc051 BK	365	}
	366	_M_last_overflowed = true;
	367	return __ret;
	368	}
	369
990101f9	370	template<typename _CharT, typename _Traits>
31bfa177	371	typename basic_filebuf<_CharT, _Traits>::__streambuf_type*
990101f9 BK	372	basic_filebuf<_CharT, _Traits>::
	373	setbuf(char_type* __s, streamsize __n)
	374	{
	375	if (!this->is_open() && __s == 0 && __n == 0)
	376	_M_buf_size_opt = 0;
	377	else if (__s && __n)
	378	{
	379	// This is implementation-defined behavior, and assumes
	380	// that an external char_type array of length (__s + __n)
	381	// exists and has been pre-allocated. If this is not the
	382	// case, things will quickly blow up.
	383	// Step 1: Destroy the current internal array.
	384	_M_destroy_internal_buffer();
	385
	386	// Step 2: Use the external array.
	387	_M_buf = __s;
	388	_M_buf_size_opt = _M_buf_size = __n;
	389	_M_set_indeterminate();
990101f9 BK	390	}
	391	_M_last_overflowed = false;
	392	return this;
	393	}
	394
725dc051	395	template<typename _CharT, typename _Traits>
31bfa177	396	typename basic_filebuf<_CharT, _Traits>::pos_type
725dc051 BK	397	basic_filebuf<_CharT, _Traits>::
	398	seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
	399	{
	400	pos_type __ret = pos_type(off_type(-1));
dcf5a5de BK	401	bool __testin = (ios_base::in & _M_mode & __mode) != 0;
dcf5a5de BK	402	bool __testout = (ios_base::out & _M_mode & __mode) != 0;
69302d8b BK	403
	404	// Should probably do has_facet checks here.
	405	int __width = use_facet<__codecvt_type>(_M_buf_locale).encoding();
725dc051 BK	406	if (__width < 0)
725dc051 BK	407	__width = 0;
b988dfc5	408	bool __testfail = __off != 0 && __width <= 0;
725dc051	409
dcf5a5de	410	if (this->is_open() && !__testfail && (__testin \|\| __testout))
725dc051 BK	411	{
	412	// Ditch any pback buffers to avoid confusion.
	413	_M_pback_destroy();
	414
	415	if (__way != ios_base::cur \|\| __off != 0)
	416	{
	417	off_type __computed_off = __width * __off;
	418
	419	bool __testget = _M_in_cur && _M_in_beg < _M_in_end;
	420	bool __testput = _M_out_cur && _M_out_beg < _M_out_end;
	421	// Sync the internal and external streams.
	422	// out
	423	if (__testput \|\| _M_last_overflowed)
	424	{
	425	// Part one: update the output sequence.
	426	this->sync();
	427	// Part two: output unshift sequence.
	428	_M_output_unshift();
	429	}
	430	//in
725dc051	431	else if (__testget && __way == ios_base::cur)
5066927d	432	__computed_off += _M_in_cur - _M_filepos;
725dc051	433
d3a193e3	434	__ret = _M_file.seekoff(__computed_off, __way, __mode);
725dc051 BK	435	_M_set_indeterminate();
	436	}
	437	// NB: Need to do this in case _M_file in indeterminate
d3a193e3	438	// state, ie _M_file._offset == -1
725dc051 BK	439	else
725dc051 BK	440	{
d3a193e3	441	__ret = _M_file.seekoff(__off, ios_base::cur, __mode);
4977bab6	442	__ret += std::max(_M_out_cur, _M_in_cur) - _M_filepos;
725dc051 BK	443	}
	444	}
	445	_M_last_overflowed = false;
	446	return __ret;
	447	}
	448
	449	template<typename _CharT, typename _Traits>
31bfa177	450	typename basic_filebuf<_CharT, _Traits>::pos_type
725dc051 BK	451	basic_filebuf<_CharT, _Traits>::
	452	seekpos(pos_type __pos, ios_base::openmode __mode)
	453	{
b988dfc5 BK	454	#ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS
	455	// 171. Strange seekpos() semantics due to joint position
	456	return this->seekoff(off_type(__pos), ios_base::beg, __mode);
	457	#endif
725dc051 BK	458	}
	459
	460	template<typename _CharT, typename _Traits>
	461	void
	462	basic_filebuf<_CharT, _Traits>::
	463	_M_output_unshift()
	464	{ }
	465
	466	template<typename _CharT, typename _Traits>
	467	void
	468	basic_filebuf<_CharT, _Traits>::
	469	imbue(const locale& __loc)
	470	{
	471	bool __testbeg = gptr() == eback() && pptr() == pbase();
69302d8b BK	472
69302d8b BK	473	if (__testbeg && _M_buf_locale != __loc)
725dc051	474	{
725dc051	475	_M_buf_locale = __loc;
69302d8b	476	_M_buf_locale_init = true;
725dc051	477	}
69302d8b	478
725dc051 BK	479	// NB this may require the reconversion of previously
	480	// converted chars. This in turn may cause the reconstruction
	481	// of the original file. YIKES!!
	482	// XXX The part in the above comment is not done.
	483	_M_last_overflowed = false;
	484	}
a32e3c09 BK	485
	486	// Inhibit implicit instantiations for required instantiations,
	487	// which are defined via explicit instantiations elsewhere.
	488	// NB: This syntax is a GNU extension.
	489	extern template class basic_filebuf<char>;
a32e3c09	490	extern template class basic_ifstream<char>;
a32e3c09	491	extern template class basic_ofstream<char>;
a32e3c09	492	extern template class basic_fstream<char>;
5112ae3a BK	493
	494	#ifdef _GLIBCPP_USE_WCHAR_T
	495	extern template class basic_filebuf<wchar_t>;
	496	extern template class basic_ifstream<wchar_t>;
	497	extern template class basic_ofstream<wchar_t>;
a32e3c09	498	extern template class basic_fstream<wchar_t>;
5112ae3a	499	#endif
725dc051 BK	500	} // namespace std
725dc051 BK	501
6f48900c	502	#endif