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   // Definitions for static const data members of __ios_flags.
  42   const __ios_flags::__int_type __ios_flags::_S_boolalpha;
  43   const __ios_flags::__int_type __ios_flags::_S_dec;
  44   const __ios_flags::__int_type __ios_flags::_S_fixed;
  45   const __ios_flags::__int_type __ios_flags::_S_hex;
  46   const __ios_flags::__int_type __ios_flags::_S_internal;
  47   const __ios_flags::__int_type __ios_flags::_S_left;
  48   const __ios_flags::__int_type __ios_flags::_S_oct;
  49   const __ios_flags::__int_type __ios_flags::_S_right;
  50   const __ios_flags::__int_type __ios_flags::_S_scientific;
  51   const __ios_flags::__int_type __ios_flags::_S_showbase;
  52   const __ios_flags::__int_type __ios_flags::_S_showpoint;
  53   const __ios_flags::__int_type __ios_flags::_S_showpos;
  54   const __ios_flags::__int_type __ios_flags::_S_skipws;
  55   const __ios_flags::__int_type __ios_flags::_S_unitbuf;
  56   const __ios_flags::__int_type __ios_flags::_S_uppercase;
  57   const __ios_flags::__int_type __ios_flags::_S_adjustfield;
  58   const __ios_flags::__int_type __ios_flags::_S_basefield;
  59   const __ios_flags::__int_type __ios_flags::_S_floatfield;
  60
  61   const __ios_flags::__int_type __ios_flags::_S_badbit;
  62   const __ios_flags::__int_type __ios_flags::_S_eofbit;
  63   const __ios_flags::__int_type __ios_flags::_S_failbit;
  64
  65   const __ios_flags::__int_type __ios_flags::_S_app;
  66   const __ios_flags::__int_type __ios_flags::_S_ate;
  67   const __ios_flags::__int_type __ios_flags::_S_bin;
  68   const __ios_flags::__int_type __ios_flags::_S_in;
  69   const __ios_flags::__int_type __ios_flags::_S_out;
  70   const __ios_flags::__int_type __ios_flags::_S_trunc;
  71
  72   // Definitions for static const members of ios_base.
  73   const ios_base::fmtflags ios_base::boolalpha;
  74   const ios_base::fmtflags ios_base::dec;
  75   const ios_base::fmtflags ios_base::fixed;
  76   const ios_base::fmtflags ios_base::hex;
  77   const ios_base::fmtflags ios_base::internal;
  78   const ios_base::fmtflags ios_base::left;
  79   const ios_base::fmtflags ios_base::oct;
  80   const ios_base::fmtflags ios_base::right;
  81   const ios_base::fmtflags ios_base::scientific;
  82   const ios_base::fmtflags ios_base::showbase;
  83   const ios_base::fmtflags ios_base::showpoint;
  84   const ios_base::fmtflags ios_base::showpos;
  85   const ios_base::fmtflags ios_base::skipws;
  86   const ios_base::fmtflags ios_base::unitbuf;
  87   const ios_base::fmtflags ios_base::uppercase;
  88   const ios_base::fmtflags ios_base::adjustfield;
  89   const ios_base::fmtflags ios_base::basefield;
  90   const ios_base::fmtflags ios_base::floatfield;
  91
  92   const ios_base::iostate ios_base::badbit;
  93   const ios_base::iostate ios_base::eofbit;
  94   const ios_base::iostate ios_base::failbit;
  95   const ios_base::iostate ios_base::goodbit;
  96
  97   const ios_base::openmode ios_base::app;
  98   const ios_base::openmode ios_base::ate;
  99   const ios_base::openmode ios_base::binary;
 100   const ios_base::openmode ios_base::in;
 101   const ios_base::openmode ios_base::out;
 102   const ios_base::openmode ios_base::trunc;
 103
 104   const ios_base::seekdir ios_base::beg;
 105   const ios_base::seekdir ios_base::cur;
 106   const ios_base::seekdir ios_base::end;
 107
 108   const int ios_base::_S_local_words;
 109   int ios_base::Init::_S_ios_base_init = 0;
 110   bool ios_base::Init::_S_synced_with_stdio = true;
 111
 112   extern istream cin;
 113   extern ostream cout;
 114   extern ostream cerr;
 115   extern ostream clog;
 116 #ifdef _GLIBCPP_USE_WCHAR_T
 117   extern wistream wcin;
 118   extern wostream wcout;
 119   extern wostream wcerr;
 120   extern wostream wclog;
 121 #endif
 122
 123   ios_base::failure::failure(const string& __str) throw()
 124   {
 125     strncpy(_M_name, __str.c_str(), _M_bufsize);
 126     _M_name[_M_bufsize - 1] = '\0';
 127   }
 128
 129   ios_base::failure::~failure() throw()
 130   { }
 131
 132   const char*
 133   ios_base::failure::what() const throw()
 134   { return _M_name; }
 135
 136   ios_base::Init::Init()
 137   {
 138     if (++_S_ios_base_init == 1)
 139       {
 140         // NB: std_iostream.h creates the four standard files with
 141         // NULL buffers. At this point, we swap out these placeholder
 142         // objects for the properly-constructed ones
 143         _M_cout = new filebuf(1, "stdout", ios_base::out);
 144         _M_cin = new filebuf(0, "stdin", ios_base::in);
 145         _M_cerr = new filebuf(2, "stderr", ios_base::out);
 146         new (&cout) ostream(_M_cout);
 147         new (&cin) istream(_M_cin);
 148         new (&cerr) ostream(_M_cerr);
 149         new (&clog) ostream(_M_cerr);
 150         cin.tie(&cout);
 151         cerr.flags(ios_base::unitbuf);
 152
 153 #ifdef _GLIBCPP_USE_WCHAR_T
 154         _M_wcout = new wfilebuf(1, "stdout", ios_base::out);
 155         _M_wcin = new wfilebuf(0, "stdin", ios_base::in);
 156         _M_wcerr = new wfilebuf(2, "stderr", ios_base::out);
 157         new (&wcout) wostream(_M_wcout);
 158         new (&wcin) wistream(_M_wcin);
 159         new (&wcerr) wostream(_M_wcerr);
 160         new (&wclog) wostream(_M_wcerr);
 161         wcin.tie(&wcout);
 162         wcerr.flags(ios_base::unitbuf);
 163 #endif
 164         ios_base::Init::_S_synced_with_stdio = true;
 165       }
 166   }
 167
 168   ios_base::Init::~Init()
 169   {
 170     if (--_S_ios_base_init == 0)
 171       {
 172         cout.flush();
 173         cerr.flush();
 174         clog.flush();
 175         delete _M_cout;
 176         delete _M_cin;
 177         delete _M_cerr;
 178         _M_cout = NULL;
 179         _M_cin = NULL;
 180         _M_cerr = NULL;
 181 #ifdef _GLIBCPP_USE_WCHAR_T
 182         wcout.flush();
 183         wcerr.flush();
 184         wclog.flush();
 185         delete _M_wcout;
 186         delete _M_wcin;
 187         delete _M_wcerr;
 188         _M_wcout = NULL;
 189         _M_wcin = NULL;
 190         _M_wcerr = NULL;
 191 #endif
 192       }
 193   }
 194
 195   // 27.4.2.5  ios_base storage functions
 196   int
 197   ios_base::xalloc() throw()
 198   {
 199     // XXX MT
 200     // XXX should be a symbol. (Reserve 0..3 for builtins.)
 201     static int top = 4;
 202     return top++;
 203   }
 204
 205   // 27.4.2.5  iword/pword storage
 206   ios_base::_Words&
 207   ios_base::_M_grow_words(int ix)
 208   {
 209     // Precondition: _M_word_limit <= ix
 210     _Words zero = { 0, 0 };
 211     int newlimit = _S_local_words;
 212     _Words* words = _M_word_array;
 213     int i = 0;
 214     if (_S_local_words <= ix)
 215       {
 216         newlimit = ix+1;
 217         try
 218           { words = new _Words[ix+1]; }
 219         catch (...)
 220           {
 221             _M_dummy = zero;  // XXX MT? Not on "normal" machines.
 222             // XXX now in basic_ios
 223             // _M_clear(_M_rdstate() | badbit);  // may throw
 224             return _M_dummy;
 225           }
 226         for (; i < _M_word_limit; i++)
 227           words[i] = _M_words[i];
 228         if (_M_words != _M_word_array)
 229           delete [] _M_words;
 230       }
 231
 232     do { words[i] = zero; } while (++i < newlimit);
 233     _M_words = words;
 234     _M_word_limit = newlimit;
 235     return words[ix];
 236   }
 237
 238   // Called only by basic_ios<>::init.
 239   void
 240   ios_base::_M_init()
 241   {
 242     // NB: May be called more than once
 243     _M_precision = 6;
 244     _M_width = 0;
 245     _M_flags = skipws | dec;
 246     _M_callbacks = 0;
 247     _M_words = 0;
 248     _M_word_limit = 0;
 249     _M_ios_locale = locale();
 250     // No init needed for _M_word_array or _M_dummy.
 251   }
 252
 253   // 27.4.2.3  ios_base locale functions
 254   locale
 255   ios_base::imbue(const locale& __loc)
 256   {
 257     locale __old = _M_ios_locale;
 258     _M_ios_locale = __loc;
 259     // Make sure there's a callback for the format caches so they will be
 260     // marked dirty.
 261     _Format_cache<char>::_S_get(*this);
 262 #ifdef _GLIBCPP_USE_WCHAR_T
 263     _Format_cache<wchar_t>::_S_get(*this);
 264 #endif
 265     _M_call_callbacks(imbue_event);
 266     return __old;
 267   }
 268
 269   ios_base::ios_base()
 270   {
 271     // Do nothing; init() does it.  Static init to 0 makes everything sane.
 272   }
 273
 274   // 27.4.2.7  ios_base constructors/destructors
 275   ios_base::~ios_base()
 276   {
 277     _M_call_callbacks(erase_event);
 278     _M_dispose_callbacks();
 279     if (_M_words != _M_word_array)
 280       delete [] _M_words;
 281     // XXX done?
 282   }
 283
 284   void
 285   ios_base::register_callback(event_callback __fn, int __index)
 286   { _M_callbacks = new _Callback_list(__fn, __index, _M_callbacks); }
 287
 288   void
 289   ios_base::_M_call_callbacks(event __e) throw()
 290   {
 291     for (_Callback_list* __p = _M_callbacks; __p; __p = __p->_M_next)
 292       {
 293         try {
 294           (*__p->_M_fn) (__e, *this, __p->_M_index);
 295         }
 296         catch (...) {
 297         }
 298       }
 299   }
 300
 301   void
 302   ios_base::_M_dispose_callbacks(void)
 303   {
 304     _Callback_list* __p = _M_callbacks;
 305     while (__p && __p->_M_remove_reference() == 0)
 306       {
 307         _Callback_list* __next = __p->_M_next;
 308         delete __p;
 309         __p = __next;
 310       }
 311     _M_callbacks = 0;
 312   }
 313
 314   bool
 315   ios_base::sync_with_stdio(bool __sync)
 316   {
 317 #ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS
 318     // 49.  Underspecification of ios_base::sync_with_stdio
 319     bool __ret = ios_base::Init::_S_synced_with_stdio;
 320 #endif
 321
 322     // Turn off sync with C FILE* for cin, cout, cerr, clog iff
 323     // currently synchronized.
 324     if (!__sync && __ret)
 325       {
 326 #if 0
 327         // no longer need to do this
 328         // Need to dispose of the buffers created at initialization.
 329         __ioinit._M_cout->~filebuf();
 330         __ioinit._M_cin->~filebuf();
 331         __ioinit._M_cerr->~filebuf();
 332         __ioinit._M_cout = new filebuf();
 333         __ioinit._M_cin = new filebuf();
 334         __ioinit._M_cerr = new filebuf();
 335         __ioinit._M_cout->open("stdout", ios_base::out);
 336         __ioinit._M_cin->open("stdin", ios_base::in);
 337         __ioinit._M_cerr->open("stderr", ios_base::out);
 338         cout.rdbuf(__ioinit._M_cout);
 339         cin.rdbuf(__ioinit._M_cin);
 340         cerr.rdbuf(__ioinit._M_cerr);
 341         cerr.flags(ios_base::unitbuf);
 342         clog.rdbuf(__ioinit._M_cerr);
 343 #endif
 344 #ifdef _GLIBCPP_USE_WCHAR_T
 345 #endif
 346         ios_base::Init::_S_synced_with_stdio = false;
 347       }
 348
 349     return __ret;
 350   }
 351
 352 }  // namespace std
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364