xref: /freebsd-12.1/contrib/libstdc++/src/ios.cc (revision f8a1b7d9)

// Iostreams base classes -*- C++ -*-

// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
// 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// 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: 27.4  Iostreams base classes
//

#include <ios>
#include <limits>

_GLIBCXX_BEGIN_NAMESPACE(std)

  // Definitions for static const members of ios_base.
  const ios_base::fmtflags ios_base::boolalpha;
  const ios_base::fmtflags ios_base::dec;
  const ios_base::fmtflags ios_base::fixed;
  const ios_base::fmtflags ios_base::hex;
  const ios_base::fmtflags ios_base::internal;
  const ios_base::fmtflags ios_base::left;
  const ios_base::fmtflags ios_base::oct;
  const ios_base::fmtflags ios_base::right;
  const ios_base::fmtflags ios_base::scientific;
  const ios_base::fmtflags ios_base::showbase;
  const ios_base::fmtflags ios_base::showpoint;
  const ios_base::fmtflags ios_base::showpos;
  const ios_base::fmtflags ios_base::skipws;
  const ios_base::fmtflags ios_base::unitbuf;
  const ios_base::fmtflags ios_base::uppercase;
  const ios_base::fmtflags ios_base::adjustfield;
  const ios_base::fmtflags ios_base::basefield;
  const ios_base::fmtflags ios_base::floatfield;

  const ios_base::iostate ios_base::badbit;
  const ios_base::iostate ios_base::eofbit;
  const ios_base::iostate ios_base::failbit;
  const ios_base::iostate ios_base::goodbit;

  const ios_base::openmode ios_base::app;
  const ios_base::openmode ios_base::ate;
  const ios_base::openmode ios_base::binary;
  const ios_base::openmode ios_base::in;
  const ios_base::openmode ios_base::out;
  const ios_base::openmode ios_base::trunc;

  const ios_base::seekdir ios_base::beg;
  const ios_base::seekdir ios_base::cur;
  const ios_base::seekdir ios_base::end;

  _Atomic_word ios_base::Init::_S_refcount;

  bool ios_base::Init::_S_synced_with_stdio = true;

  ios_base::ios_base()
  : _M_precision(), _M_width(), _M_flags(), _M_exception(),
  _M_streambuf_state(), _M_callbacks(0), _M_word_zero(),
  _M_word_size(_S_local_word_size), _M_word(_M_local_word), _M_ios_locale()
  {
    // Do nothing: basic_ios::init() does it.
    // NB: _M_callbacks and _M_word must be zero for non-initialized
    // ios_base to go through ~ios_base gracefully.
  }

  // 27.4.2.7  ios_base constructors/destructors
  ios_base::~ios_base()
  {
    _M_call_callbacks(erase_event);
    _M_dispose_callbacks();
    if (_M_word != _M_local_word)
      {
	delete [] _M_word;
	_M_word = 0;
      }
  }

  // 27.4.2.5  ios_base storage functions
  int
  ios_base::xalloc() throw()
  {
    // Implementation note: Initialize top to zero to ensure that
    // initialization occurs before main() is started.
    static _Atomic_word _S_top = 0;
    return __gnu_cxx::__exchange_and_add_dispatch(&_S_top, 1) + 4;
  }

  void
  ios_base::register_callback(event_callback __fn, int __index)
  { _M_callbacks = new _Callback_list(__fn, __index, _M_callbacks); }

  // 27.4.2.5  iword/pword storage
  ios_base::_Words&
  ios_base::_M_grow_words(int __ix, bool __iword)
  {
    // Precondition: _M_word_size <= __ix
    int __newsize = _S_local_word_size;
    _Words* __words = _M_local_word;
    if (__ix > _S_local_word_size - 1)
      {
	if (__ix < numeric_limits<int>::max())
	  {
	    __newsize = __ix + 1;
	    try
	      { __words = new _Words[__newsize]; }
	    catch (...)
	      {
		_M_streambuf_state |= badbit;
		if (_M_streambuf_state & _M_exception)
		  __throw_ios_failure(__N("ios_base::_M_grow_words "
				      "allocation failed"));
		if (__iword)
		  _M_word_zero._M_iword = 0;
		else
		  _M_word_zero._M_pword = 0;
		return _M_word_zero;
	      }
	    for (int __i = 0; __i < _M_word_size; __i++)
	      __words[__i] = _M_word[__i];
	    if (_M_word && _M_word != _M_local_word)
	      {
		delete [] _M_word;
		_M_word = 0;
	      }
	  }
	else
	  {
	    _M_streambuf_state |= badbit;
	    if (_M_streambuf_state & _M_exception)
	      __throw_ios_failure(__N("ios_base::_M_grow_words is not valid"));
	    if (__iword)
	      _M_word_zero._M_iword = 0;
	    else
	      _M_word_zero._M_pword = 0;
	    return _M_word_zero;
	  }
      }
    _M_word = __words;
    _M_word_size = __newsize;
    return _M_word[__ix];
  }

  void
  ios_base::_M_call_callbacks(event __e) throw()
  {
    _Callback_list* __p = _M_callbacks;
    while (__p)
      {
	try
	  { (*__p->_M_fn) (__e, *this, __p->_M_index); }
	catch (...)
	  { }
	__p = __p->_M_next;
      }
  }

  void
  ios_base::_M_dispose_callbacks(void)
  {
    _Callback_list* __p = _M_callbacks;
    while (__p && __p->_M_remove_reference() == 0)
      {
	_Callback_list* __next = __p->_M_next;
	delete __p;
	__p = __next;
      }
    _M_callbacks = 0;
  }

_GLIBCXX_END_NAMESPACE