libstdc++-v3/src/ios.cc

   1 // Iostreams base classes -*- C++ -*-
   2
   3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
   4 // 2006, 2007, 2008, 2009
   5 // Free Software Foundation, Inc.
   6 //
   7 // This file is part of the GNU ISO C++ Library.  This library is free
   8 // software; you can redistribute it and/or modify it under the
   9 // terms of the GNU General Public License as published by the
  10 // Free Software Foundation; either version 2, or (at your option)
  11 // any later version.
  12
  13 // This library is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License along
  19 // with this library; see the file COPYING.  If not, write to the Free
  20 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  21 // USA.
  22
  23 // As a special exception, you may use this file as part of a free software
  24 // library without restriction.  Specifically, if other files instantiate
  25 // templates or use macros or inline functions from this file, or you compile
  26 // this file and link it with other files to produce an executable, this
  27 // file does not by itself cause the resulting executable to be covered by
  28 // the GNU General Public License.  This exception does not however
  29 // invalidate any other reasons why the executable file might be covered by
  30 // the GNU General Public License.
  31
  32 //
  33 // ISO C++ 14882: 27.4  Iostreams base classes
  34 //
  35
  36 #include <ios>
  37 #include <limits>
  38
  39 _GLIBCXX_BEGIN_NAMESPACE(std)
  40
  41   // Definitions for static const members of ios_base.
  42   const ios_base::fmtflags ios_base::boolalpha;
  43   const ios_base::fmtflags ios_base::dec;
  44   const ios_base::fmtflags ios_base::fixed;
  45   const ios_base::fmtflags ios_base::hex;
  46   const ios_base::fmtflags ios_base::internal;
  47   const ios_base::fmtflags ios_base::left;
  48   const ios_base::fmtflags ios_base::oct;
  49   const ios_base::fmtflags ios_base::right;
  50   const ios_base::fmtflags ios_base::scientific;
  51   const ios_base::fmtflags ios_base::showbase;
  52   const ios_base::fmtflags ios_base::showpoint;
  53   const ios_base::fmtflags ios_base::showpos;
  54   const ios_base::fmtflags ios_base::skipws;
  55   const ios_base::fmtflags ios_base::unitbuf;
  56   const ios_base::fmtflags ios_base::uppercase;
  57   const ios_base::fmtflags ios_base::adjustfield;
  58   const ios_base::fmtflags ios_base::basefield;
  59   const ios_base::fmtflags ios_base::floatfield;
  60
  61   const ios_base::iostate ios_base::badbit;
  62   const ios_base::iostate ios_base::eofbit;
  63   const ios_base::iostate ios_base::failbit;
  64   const ios_base::iostate ios_base::goodbit;
  65
  66   const ios_base::openmode ios_base::app;
  67   const ios_base::openmode ios_base::ate;
  68   const ios_base::openmode ios_base::binary;
  69   const ios_base::openmode ios_base::in;
  70   const ios_base::openmode ios_base::out;
  71   const ios_base::openmode ios_base::trunc;
  72
  73   const ios_base::seekdir ios_base::beg;
  74   const ios_base::seekdir ios_base::cur;
  75   const ios_base::seekdir ios_base::end;
  76
  77   _Atomic_word ios_base::Init::_S_refcount;
  78
  79   bool ios_base::Init::_S_synced_with_stdio = true;
  80
  81   ios_base::ios_base()
  82   : _M_precision(), _M_width(), _M_flags(), _M_exception(),
  83   _M_streambuf_state(), _M_callbacks(0), _M_word_zero(),
  84   _M_word_size(_S_local_word_size), _M_word(_M_local_word), _M_ios_locale()
  85   {
  86     // Do nothing: basic_ios::init() does it.
  87     // NB: _M_callbacks and _M_word must be zero for non-initialized
  88     // ios_base to go through ~ios_base gracefully.
  89   }
  90
  91   // 27.4.2.7  ios_base constructors/destructors
  92   ios_base::~ios_base()
  93   {
  94     _M_call_callbacks(erase_event);
  95     _M_dispose_callbacks();
  96     if (_M_word != _M_local_word)
  97       {
  98         delete [] _M_word;
  99         _M_word = 0;
 100       }
 101   }
 102
 103   // 27.4.2.5  ios_base storage functions
 104   int
 105   ios_base::xalloc() throw()
 106   {
 107     // Implementation note: Initialize top to zero to ensure that
 108     // initialization occurs before main() is started.
 109     static _Atomic_word _S_top = 0;
 110     return __gnu_cxx::__exchange_and_add_dispatch(&_S_top, 1) + 4;
 111   }
 112
 113   void
 114   ios_base::register_callback(event_callback __fn, int __index)
 115   { _M_callbacks = new _Callback_list(__fn, __index, _M_callbacks); }
 116
 117   // 27.4.2.5  iword/pword storage
 118   ios_base::_Words&
 119   ios_base::_M_grow_words(int __ix, bool __iword)
 120   {
 121     // Precondition: _M_word_size <= __ix
 122     int __newsize = _S_local_word_size;
 123     _Words* __words = _M_local_word;
 124     if (__ix > _S_local_word_size - 1)
 125       {
 126         if (__ix < numeric_limits<int>::max())
 127           {
 128             __newsize = __ix + 1;
 129             __try
 130               { __words = new _Words[__newsize]; }
 131             __catch(...)
 132               {
 133                 _M_streambuf_state |= badbit;
 134                 if (_M_streambuf_state & _M_exception)
 135                   __throw_ios_failure(__N("ios_base::_M_grow_words "
 136                                       "allocation failed"));
 137                 if (__iword)
 138                   _M_word_zero._M_iword = 0;
 139                 else
 140                   _M_word_zero._M_pword = 0;
 141                 return _M_word_zero;
 142               }
 143             for (int __i = 0; __i < _M_word_size; __i++)
 144               __words[__i] = _M_word[__i];
 145             if (_M_word && _M_word != _M_local_word)
 146               {
 147                 delete [] _M_word;
 148                 _M_word = 0;
 149               }
 150           }
 151         else
 152           {
 153             _M_streambuf_state |= badbit;
 154             if (_M_streambuf_state & _M_exception)
 155               __throw_ios_failure(__N("ios_base::_M_grow_words is not valid"));
 156             if (__iword)
 157               _M_word_zero._M_iword = 0;
 158             else
 159               _M_word_zero._M_pword = 0;
 160             return _M_word_zero;
 161           }
 162       }
 163     _M_word = __words;
 164     _M_word_size = __newsize;
 165     return _M_word[__ix];
 166   }
 167
 168   void
 169   ios_base::_M_call_callbacks(event __e) throw()
 170   {
 171     _Callback_list* __p = _M_callbacks;
 172     while (__p)
 173       {
 174         __try
 175           { (*__p->_M_fn) (__e, *this, __p->_M_index); }
 176         __catch(...)
 177           { }
 178         __p = __p->_M_next;
 179       }
 180   }
 181
 182   void
 183   ios_base::_M_dispose_callbacks(void)
 184   {
 185     _Callback_list* __p = _M_callbacks;
 186     while (__p && __p->_M_remove_reference() == 0)
 187       {
 188         _Callback_list* __next = __p->_M_next;
 189         delete __p;
 190         __p = __next;
 191       }
 192     _M_callbacks = 0;
 193   }
 194
 195 _GLIBCXX_END_NAMESPACE