libstdc++-v3/src/ios.cc

   1 // Iostreams base classes -*- C++ -*-
   2
   3 // Copyright (C) 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 2, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING.  If not, write to the Free
  18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  19 // USA.
  20
  21 // As a special exception, you may use this file as part of a free software
  22 // library without restriction.  Specifically, if other files instantiate
  23 // templates or use macros or inline functions from this file, or you compile
  24 // this file and link it with other files to produce an executable, this
  25 // file does not by itself cause the resulting executable to be covered by
  26 // the GNU General Public License.  This exception does not however
  27 // invalidate any other reasons why the executable file might be covered by
  28 // the GNU General Public License.
  29
  30 //
  31 // ISO C++ 14882: 27.4  Iostreams base classes
  32 //
  33
  34 #include <bits/std_ios.h>
  35 #include <bits/std_ostream.h>
  36 #include <bits/std_istream.h>
  37 #include <bits/std_fstream.h>
  38
  39 namespace std
  40 {
  41   // Extern declarations for global objects in src/globals.cc.
  42   extern istream cin;
  43   extern ostream cout;
  44   extern ostream cerr;
  45   extern ostream clog;
  46   extern filebuf buf_cout;
  47   extern filebuf buf_cin;
  48   extern filebuf buf_cerr;
  49
  50 #ifdef _GLIBCPP_USE_WCHAR_T
  51   extern wistream wcin;
  52   extern wostream wcout;
  53   extern wostream wcerr;
  54   extern wostream wclog;
  55   extern wfilebuf buf_wcout;
  56   extern wfilebuf buf_wcin;
  57   extern wfilebuf buf_wcerr;
  58 #endif
  59
  60   // Definitions for static const data members of __ios_flags.
  61   const __ios_flags::__int_type __ios_flags::_S_boolalpha;
  62   const __ios_flags::__int_type __ios_flags::_S_dec;
  63   const __ios_flags::__int_type __ios_flags::_S_fixed;
  64   const __ios_flags::__int_type __ios_flags::_S_hex;
  65   const __ios_flags::__int_type __ios_flags::_S_internal;
  66   const __ios_flags::__int_type __ios_flags::_S_left;
  67   const __ios_flags::__int_type __ios_flags::_S_oct;
  68   const __ios_flags::__int_type __ios_flags::_S_right;
  69   const __ios_flags::__int_type __ios_flags::_S_scientific;
  70   const __ios_flags::__int_type __ios_flags::_S_showbase;
  71   const __ios_flags::__int_type __ios_flags::_S_showpoint;
  72   const __ios_flags::__int_type __ios_flags::_S_showpos;
  73   const __ios_flags::__int_type __ios_flags::_S_skipws;
  74   const __ios_flags::__int_type __ios_flags::_S_unitbuf;
  75   const __ios_flags::__int_type __ios_flags::_S_uppercase;
  76   const __ios_flags::__int_type __ios_flags::_S_adjustfield;
  77   const __ios_flags::__int_type __ios_flags::_S_basefield;
  78   const __ios_flags::__int_type __ios_flags::_S_floatfield;
  79
  80   const __ios_flags::__int_type __ios_flags::_S_badbit;
  81   const __ios_flags::__int_type __ios_flags::_S_eofbit;
  82   const __ios_flags::__int_type __ios_flags::_S_failbit;
  83
  84   const __ios_flags::__int_type __ios_flags::_S_app;
  85   const __ios_flags::__int_type __ios_flags::_S_ate;
  86   const __ios_flags::__int_type __ios_flags::_S_bin;
  87   const __ios_flags::__int_type __ios_flags::_S_in;
  88   const __ios_flags::__int_type __ios_flags::_S_out;
  89   const __ios_flags::__int_type __ios_flags::_S_trunc;
  90
  91   // Definitions for static const members of ios_base.
  92   const ios_base::fmtflags ios_base::boolalpha;
  93   const ios_base::fmtflags ios_base::dec;
  94   const ios_base::fmtflags ios_base::fixed;
  95   const ios_base::fmtflags ios_base::hex;
  96   const ios_base::fmtflags ios_base::internal;
  97   const ios_base::fmtflags ios_base::left;
  98   const ios_base::fmtflags ios_base::oct;
  99   const ios_base::fmtflags ios_base::right;
 100   const ios_base::fmtflags ios_base::scientific;
 101   const ios_base::fmtflags ios_base::showbase;
 102   const ios_base::fmtflags ios_base::showpoint;
 103   const ios_base::fmtflags ios_base::showpos;
 104   const ios_base::fmtflags ios_base::skipws;
 105   const ios_base::fmtflags ios_base::unitbuf;
 106   const ios_base::fmtflags ios_base::uppercase;
 107   const ios_base::fmtflags ios_base::adjustfield;
 108   const ios_base::fmtflags ios_base::basefield;
 109   const ios_base::fmtflags ios_base::floatfield;
 110
 111   const ios_base::iostate ios_base::badbit;
 112   const ios_base::iostate ios_base::eofbit;
 113   const ios_base::iostate ios_base::failbit;
 114   const ios_base::iostate ios_base::goodbit;
 115
 116   const ios_base::openmode ios_base::app;
 117   const ios_base::openmode ios_base::ate;
 118   const ios_base::openmode ios_base::binary;
 119   const ios_base::openmode ios_base::in;
 120   const ios_base::openmode ios_base::out;
 121   const ios_base::openmode ios_base::trunc;
 122
 123   const ios_base::seekdir ios_base::beg;
 124   const ios_base::seekdir ios_base::cur;
 125   const ios_base::seekdir ios_base::end;
 126
 127   const int ios_base::_S_local_words;
 128   int ios_base::Init::_S_ios_base_init = 0;
 129   bool ios_base::Init::_S_synced_with_stdio = true;
 130
 131   ios_base::failure::failure(const string& __str) throw()
 132   {
 133     strncpy(_M_name, __str.c_str(), _M_bufsize);
 134     _M_name[_M_bufsize - 1] = '\0';
 135   }
 136
 137   ios_base::failure::~failure() throw()
 138   { }
 139
 140   const char*
 141   ios_base::failure::what() const throw()
 142   { return _M_name; }
 143
 144   void
 145   ios_base::Init::_S_ios_create(bool __sync)
 146   {
 147     int __bufsize = __sync ? 0 : static_cast<int>(BUFSIZ);
 148
 149     // NB: The file globals.cc creates the four standard files
 150     // with NULL buffers. At this point, we swap out the dummy NULL
 151     // [io]stream objects and buffers with the real deal.
 152     new (&buf_cout) filebuf(stdout, ios_base::out, __bufsize);
 153     new (&buf_cin) filebuf(stdin, ios_base::in, 1);
 154     new (&buf_cerr) filebuf(stderr, ios_base::out, __bufsize);
 155     new (&cout) ostream(&buf_cout);
 156     new (&cin) istream(&buf_cin);
 157     new (&cerr) ostream(&buf_cerr);
 158     new (&clog) ostream(&buf_cerr);
 159     cin.tie(&cout);
 160     cerr.flags(ios_base::unitbuf);
 161
 162 #ifdef _GLIBCPP_USE_WCHAR_T
 163     new (&buf_wcout) wfilebuf(stdout, ios_base::out, __bufsize);
 164     new (&buf_wcin) wfilebuf(stdin, ios_base::in, 1);
 165     new (&buf_wcerr) wfilebuf(stderr, ios_base::out, __bufsize);
 166     new (&wcout) wostream(&buf_wcout);
 167     new (&wcin) wistream(&buf_wcin);
 168     new (&wcerr) wostream(&buf_wcerr);
 169     new (&wclog) wostream(&buf_wcerr);
 170     wcin.tie(&wcout);
 171     wcerr.flags(ios_base::unitbuf);
 172 #endif
 173   }
 174
 175   void
 176   ios_base::Init::_S_ios_destroy()
 177   {
 178     // Explicitly call dtors to free any memory that is dynamically
 179     // allocated by filebuf ctor or member functions, but don't
 180     // deallocate all memory by calling operator delete.
 181     cout.flush();
 182     cerr.flush();
 183     clog.flush();
 184     buf_cout.~filebuf();
 185     buf_cin.~filebuf();
 186     buf_cerr.~filebuf();
 187 #ifdef _GLIBCPP_USE_WCHAR_T
 188     wcout.flush();
 189     wcerr.flush();
 190     wclog.flush();
 191     buf_wcout.~wfilebuf();
 192     buf_wcin.~wfilebuf();
 193     buf_wcerr.~wfilebuf();
 194 #endif
 195   }
 196
 197   ios_base::Init::Init()
 198   {
 199     if (++_S_ios_base_init == 1)
 200       {
 201         // Standard streams default to synced with "C" operations.
 202         ios_base::Init::_S_synced_with_stdio = true;
 203         _S_ios_create(ios_base::Init::_S_synced_with_stdio);
 204       }
 205   }
 206
 207   ios_base::Init::~Init()
 208   {
 209     if (--_S_ios_base_init == 0)
 210       _S_ios_destroy();
 211   }
 212
 213   // 27.4.2.5  ios_base storage functions
 214   int
 215   ios_base::xalloc() throw()
 216   {
 217     // XXX MT
 218     // XXX should be a symbol. (Reserve 0..3 for builtins.)
 219     static int top = 4;
 220     return top++;
 221   }
 222
 223   // 27.4.2.5  iword/pword storage
 224   ios_base::_Words&
 225   ios_base::_M_grow_words(int ix)
 226   {
 227     // Precondition: _M_word_limit <= ix
 228     _Words zero = { 0, 0 };
 229     int newlimit = _S_local_words;
 230     _Words* words = _M_word_array;
 231     int i = 0;
 232     if (_S_local_words <= ix)
 233       {
 234         newlimit = ix+1;
 235         try
 236           { words = new _Words[ix+1]; }
 237         catch (...)
 238           {
 239             _M_dummy = zero;  // XXX MT? Not on "normal" machines.
 240             // XXX now in basic_ios
 241             // _M_clear(_M_rdstate() | badbit);  // may throw
 242             return _M_dummy;
 243           }
 244         for (; i < _M_word_limit; i++)
 245           words[i] = _M_words[i];
 246         if (_M_words != _M_word_array)
 247           delete [] _M_words;
 248       }
 249
 250     do { words[i] = zero; } while (++i < newlimit);
 251     _M_words = words;
 252     _M_word_limit = newlimit;
 253     return words[ix];
 254   }
 255
 256   // Called only by basic_ios<>::init.
 257   void
 258   ios_base::_M_init()
 259   {
 260     // NB: May be called more than once
 261     _M_precision = 6;
 262     _M_width = 0;
 263     _M_flags = skipws | dec;
 264     _M_callbacks = 0;
 265     _M_words = 0;
 266     _M_word_limit = 0;
 267     _M_ios_locale = locale();
 268     // No init needed for _M_word_array or _M_dummy.
 269   }
 270
 271   // 27.4.2.3  ios_base locale functions
 272   locale
 273   ios_base::imbue(const locale& __loc)
 274   {
 275     locale __old = _M_ios_locale;
 276     _M_ios_locale = __loc;
 277     // Make sure there's a callback for the format caches so they will be
 278     // marked dirty.
 279     _Format_cache<char>::_S_get(*this);
 280 #ifdef _GLIBCPP_USE_WCHAR_T
 281     _Format_cache<wchar_t>::_S_get(*this);
 282 #endif
 283     _M_call_callbacks(imbue_event);
 284     return __old;
 285   }
 286
 287   ios_base::ios_base()
 288   {
 289     // Do nothing; init() does it.  Static init to 0 makes everything sane.
 290   }
 291
 292   // 27.4.2.7  ios_base constructors/destructors
 293   ios_base::~ios_base()
 294   {
 295     _M_call_callbacks(erase_event);
 296     _M_dispose_callbacks();
 297     if (_M_words != _M_word_array)
 298       delete [] _M_words;
 299     // XXX done?
 300   }
 301
 302   void
 303   ios_base::register_callback(event_callback __fn, int __index)
 304   { _M_callbacks = new _Callback_list(__fn, __index, _M_callbacks); }
 305
 306   void
 307   ios_base::_M_call_callbacks(event __e) throw()
 308   {
 309     for (_Callback_list* __p = _M_callbacks; __p; __p = __p->_M_next)
 310       {
 311         try {
 312           (*__p->_M_fn) (__e, *this, __p->_M_index);
 313         }
 314         catch (...) {
 315         }
 316       }
 317   }
 318
 319   void
 320   ios_base::_M_dispose_callbacks(void)
 321   {
 322     _Callback_list* __p = _M_callbacks;
 323     while (__p && __p->_M_remove_reference() == 0)
 324       {
 325         _Callback_list* __next = __p->_M_next;
 326         delete __p;
 327         __p = __next;
 328       }
 329     _M_callbacks = 0;
 330   }
 331
 332   bool
 333   ios_base::sync_with_stdio(bool __sync)
 334   {
 335 #ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS
 336     // 49.  Underspecification of ios_base::sync_with_stdio
 337     bool __ret = ios_base::Init::_S_synced_with_stdio;
 338 #endif
 339
 340     // Turn off sync with C FILE* for cin, cout, cerr, clog iff
 341     // currently synchronized.
 342     if (!__sync && __ret)
 343       {
 344         ios_base::Init::_S_synced_with_stdio = false;
 345         ios_base::Init::_S_ios_destroy();
 346         ios_base::Init::_S_ios_create(ios_base::Init::_S_synced_with_stdio);
 347       }
 348     return __ret;
 349   }
 350 }  // namespace std
 351