contrib/gcc-3.4/libstdc++-v3/src/ios_init.cc

   1 // Iostreams base classes -*- C++ -*-
   2
   3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
   4 // Free Software Foundation, Inc.
   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: 27.4  Iostreams base classes
  33 //
  34
  35 #include <ios>
  36 #include <ostream>
  37 #include <istream>
  38 #include <fstream>
  39 #include <bits/atomicity.h>
  40 #include <ext/stdio_filebuf.h>
  41 #include <ext/stdio_sync_filebuf.h>
  42
  43 namespace __gnu_internal
  44 {
  45   using namespace __gnu_cxx;
  46
  47   // Extern declarations for global objects in src/globals.cc.
  48   extern stdio_sync_filebuf<char> buf_cout_sync;
  49   extern stdio_sync_filebuf<char> buf_cin_sync;
  50   extern stdio_sync_filebuf<char> buf_cerr_sync;
  51
  52   extern stdio_filebuf<char> buf_cout;
  53   extern stdio_filebuf<char> buf_cin;
  54   extern stdio_filebuf<char> buf_cerr;
  55
  56 #ifdef _GLIBCXX_USE_WCHAR_T
  57   extern stdio_sync_filebuf<wchar_t> buf_wcout_sync;
  58   extern stdio_sync_filebuf<wchar_t> buf_wcin_sync;
  59   extern stdio_sync_filebuf<wchar_t> buf_wcerr_sync;
  60
  61   extern stdio_filebuf<wchar_t> buf_wcout;
  62   extern stdio_filebuf<wchar_t> buf_wcin;
  63   extern stdio_filebuf<wchar_t> buf_wcerr;
  64 #endif
  65 } // namespace __gnu_internal
  66
  67 namespace std
  68 {
  69   using namespace __gnu_internal;
  70
  71   extern istream cin;
  72   extern ostream cout;
  73   extern ostream cerr;
  74   extern ostream clog;
  75
  76 #ifdef _GLIBCXX_USE_WCHAR_T
  77   extern wistream wcin;
  78   extern wostream wcout;
  79   extern wostream wcerr;
  80   extern wostream wclog;
  81 #endif
  82
  83   ios_base::Init::Init()
  84   {
  85     if (__gnu_cxx::__exchange_and_add(&_S_refcount, 1) == 0)
  86       {
  87         // Standard streams default to synced with "C" operations.
  88         _S_synced_with_stdio = true;
  89
  90         new (&buf_cout_sync) stdio_sync_filebuf<char>(stdout);
  91         new (&buf_cin_sync) stdio_sync_filebuf<char>(stdin);
  92         new (&buf_cerr_sync) stdio_sync_filebuf<char>(stderr);
  93
  94         // The standard streams are constructed once only and never
  95         // destroyed.
  96         new (&cout) ostream(&buf_cout_sync);
  97         new (&cin) istream(&buf_cin_sync);
  98         new (&cerr) ostream(&buf_cerr_sync);
  99         new (&clog) ostream(&buf_cerr_sync);
 100         cin.tie(&cout);
 101         cerr.flags(ios_base::unitbuf);
 102
 103 #ifdef _GLIBCXX_USE_WCHAR_T
 104         new (&buf_wcout_sync) stdio_sync_filebuf<wchar_t>(stdout);
 105         new (&buf_wcin_sync) stdio_sync_filebuf<wchar_t>(stdin);
 106         new (&buf_wcerr_sync) stdio_sync_filebuf<wchar_t>(stderr);
 107
 108         new (&wcout) wostream(&buf_wcout_sync);
 109         new (&wcin) wistream(&buf_wcin_sync);
 110         new (&wcerr) wostream(&buf_wcerr_sync);
 111         new (&wclog) wostream(&buf_wcerr_sync);
 112         wcin.tie(&wcout);
 113         wcerr.flags(ios_base::unitbuf);
 114 #endif
 115
 116         // NB: Have to set refcount above one, so that standard
 117         // streams are not re-initialized with uses of ios_base::Init
 118         // besides <iostream> static object, ie just using <ios> with
 119         // ios_base::Init objects.
 120         __gnu_cxx::__atomic_add(&_S_refcount, 1);
 121       }
 122   }
 123
 124   ios_base::Init::~Init()
 125   {
 126     if (__gnu_cxx::__exchange_and_add(&_S_refcount, -1) == 2)
 127       {
 128         // Catch any exceptions thrown by basic_ostream::flush()
 129         try
 130           {
 131             // Flush standard output streams as required by 27.4.2.1.6
 132             cout.flush();
 133             cerr.flush();
 134             clog.flush();
 135
 136 #ifdef _GLIBCXX_USE_WCHAR_T
 137             wcout.flush();
 138             wcerr.flush();
 139             wclog.flush();
 140 #endif
 141           }
 142         catch (...)
 143           { }
 144       }
 145   }
 146
 147   bool
 148   ios_base::sync_with_stdio(bool __sync)
 149   {
 150     // _GLIBCXX_RESOLVE_LIB_DEFECTS
 151     // 49.  Underspecification of ios_base::sync_with_stdio
 152     bool __ret = ios_base::Init::_S_synced_with_stdio;
 153
 154     // Turn off sync with C FILE* for cin, cout, cerr, clog iff
 155     // currently synchronized.
 156     if (!__sync && __ret)
 157       {
 158         // Make sure the standard streams are constructed.
 159         ios_base::Init __init;
 160
 161         ios_base::Init::_S_synced_with_stdio = __sync;
 162
 163         // Explicitly call dtors to free any memory that is
 164         // dynamically allocated by filebuf ctor or member functions,
 165         // but don't deallocate all memory by calling operator delete.
 166         buf_cout_sync.~stdio_sync_filebuf<char>();
 167         buf_cin_sync.~stdio_sync_filebuf<char>();
 168         buf_cerr_sync.~stdio_sync_filebuf<char>();
 169
 170 #ifdef _GLIBCXX_USE_WCHAR_T
 171         buf_wcout_sync.~stdio_sync_filebuf<wchar_t>();
 172         buf_wcin_sync.~stdio_sync_filebuf<wchar_t>();
 173         buf_wcerr_sync.~stdio_sync_filebuf<wchar_t>();
 174 #endif
 175
 176         // Create stream buffers for the standard streams and use
 177         // those buffers without destroying and recreating the
 178         // streams.
 179         new (&buf_cout) stdio_filebuf<char>(stdout, ios_base::out);
 180         new (&buf_cin) stdio_filebuf<char>(stdin, ios_base::in);
 181         new (&buf_cerr) stdio_filebuf<char>(stderr, ios_base::out);
 182         cout.rdbuf(&buf_cout);
 183         cin.rdbuf(&buf_cin);
 184         cerr.rdbuf(&buf_cerr);
 185         clog.rdbuf(&buf_cerr);
 186
 187 #ifdef _GLIBCXX_USE_WCHAR_T
 188         new (&buf_wcout) stdio_filebuf<wchar_t>(stdout, ios_base::out);
 189         new (&buf_wcin) stdio_filebuf<wchar_t>(stdin, ios_base::in);
 190         new (&buf_wcerr) stdio_filebuf<wchar_t>(stderr, ios_base::out);
 191         wcout.rdbuf(&buf_wcout);
 192         wcin.rdbuf(&buf_wcin);
 193         wcerr.rdbuf(&buf_wcerr);
 194         wclog.rdbuf(&buf_wcerr);
 195 #endif
 196       }
 197     return __ret;
 198   }
 199 } // namespace std