1 // Iostreams base classes -*- C++ -*-
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002
4 // Free Software Foundation, Inc.
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)
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.
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,
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.
32 // ISO C++ 14882: 27.4 Iostreams base classes
40 #include <bits/atomicity.h>
44 // Extern declarations for global objects in src/globals.cc.
49 extern filebuf buf_cout;
50 extern filebuf buf_cin;
51 extern filebuf buf_cerr;
53 #ifdef _GLIBCPP_USE_WCHAR_T
55 extern wostream wcout;
56 extern wostream wcerr;
57 extern wostream wclog;
58 extern wfilebuf buf_wcout;
59 extern wfilebuf buf_wcin;
60 extern wfilebuf buf_wcerr;
63 // Definitions for static const data members of __ios_flags.
64 const __ios_flags::__int_type __ios_flags::_S_boolalpha;
65 const __ios_flags::__int_type __ios_flags::_S_dec;
66 const __ios_flags::__int_type __ios_flags::_S_fixed;
67 const __ios_flags::__int_type __ios_flags::_S_hex;
68 const __ios_flags::__int_type __ios_flags::_S_internal;
69 const __ios_flags::__int_type __ios_flags::_S_left;
70 const __ios_flags::__int_type __ios_flags::_S_oct;
71 const __ios_flags::__int_type __ios_flags::_S_right;
72 const __ios_flags::__int_type __ios_flags::_S_scientific;
73 const __ios_flags::__int_type __ios_flags::_S_showbase;
74 const __ios_flags::__int_type __ios_flags::_S_showpoint;
75 const __ios_flags::__int_type __ios_flags::_S_showpos;
76 const __ios_flags::__int_type __ios_flags::_S_skipws;
77 const __ios_flags::__int_type __ios_flags::_S_unitbuf;
78 const __ios_flags::__int_type __ios_flags::_S_uppercase;
79 const __ios_flags::__int_type __ios_flags::_S_adjustfield;
80 const __ios_flags::__int_type __ios_flags::_S_basefield;
81 const __ios_flags::__int_type __ios_flags::_S_floatfield;
83 const __ios_flags::__int_type __ios_flags::_S_badbit;
84 const __ios_flags::__int_type __ios_flags::_S_eofbit;
85 const __ios_flags::__int_type __ios_flags::_S_failbit;
87 const __ios_flags::__int_type __ios_flags::_S_app;
88 const __ios_flags::__int_type __ios_flags::_S_ate;
89 const __ios_flags::__int_type __ios_flags::_S_bin;
90 const __ios_flags::__int_type __ios_flags::_S_in;
91 const __ios_flags::__int_type __ios_flags::_S_out;
92 const __ios_flags::__int_type __ios_flags::_S_trunc;
94 // Definitions for static const members of ios_base.
95 const ios_base::fmtflags ios_base::boolalpha;
96 const ios_base::fmtflags ios_base::dec;
97 const ios_base::fmtflags ios_base::fixed;
98 const ios_base::fmtflags ios_base::hex;
99 const ios_base::fmtflags ios_base::internal;
100 const ios_base::fmtflags ios_base::left;
101 const ios_base::fmtflags ios_base::oct;
102 const ios_base::fmtflags ios_base::right;
103 const ios_base::fmtflags ios_base::scientific;
104 const ios_base::fmtflags ios_base::showbase;
105 const ios_base::fmtflags ios_base::showpoint;
106 const ios_base::fmtflags ios_base::showpos;
107 const ios_base::fmtflags ios_base::skipws;
108 const ios_base::fmtflags ios_base::unitbuf;
109 const ios_base::fmtflags ios_base::uppercase;
110 const ios_base::fmtflags ios_base::adjustfield;
111 const ios_base::fmtflags ios_base::basefield;
112 const ios_base::fmtflags ios_base::floatfield;
114 const ios_base::iostate ios_base::badbit;
115 const ios_base::iostate ios_base::eofbit;
116 const ios_base::iostate ios_base::failbit;
117 const ios_base::iostate ios_base::goodbit;
119 const ios_base::openmode ios_base::app;
120 const ios_base::openmode ios_base::ate;
121 const ios_base::openmode ios_base::binary;
122 const ios_base::openmode ios_base::in;
123 const ios_base::openmode ios_base::out;
124 const ios_base::openmode ios_base::trunc;
126 const ios_base::seekdir ios_base::beg;
127 const ios_base::seekdir ios_base::cur;
128 const ios_base::seekdir ios_base::end;
130 const int ios_base::_S_local_word_size;
131 int ios_base::Init::_S_ios_base_init = 0;
132 bool ios_base::Init::_S_synced_with_stdio = true;
134 ios_base::failure::failure(const string& __str) throw()
136 strncpy(_M_name, __str.c_str(), _M_bufsize);
137 _M_name[_M_bufsize - 1] = '\0';
140 ios_base::failure::~failure() throw()
144 ios_base::failure::what() const throw()
148 ios_base::Init::_S_ios_create(bool __sync)
150 int __out_bufsize = __sync ? 0 : static_cast<int>(BUFSIZ);
151 int __in_bufsize = __sync ? 1 : static_cast<int>(BUFSIZ);
153 #if _GLIBCPP_AVOID_FSEEK
154 // Platforms that prefer to avoid fseek() calls on streams only
155 // get their desire when the C++-layer input buffer size is 1.
156 // This hack hurts performance but keeps correctness across
157 // all types of streams that might be attached to (e.g.) cin.
161 // NB: The file globals.cc creates the four standard files
162 // with NULL buffers. At this point, we swap out the dummy NULL
163 // [io]stream objects and buffers with the real deal.
164 new (&buf_cout) filebuf(stdout, ios_base::out, __out_bufsize);
165 new (&buf_cin) filebuf(stdin, ios_base::in, __in_bufsize);
166 new (&buf_cerr) filebuf(stderr, ios_base::out, __out_bufsize);
167 new (&cout) ostream(&buf_cout);
168 new (&cin) istream(&buf_cin);
169 new (&cerr) ostream(&buf_cerr);
170 new (&clog) ostream(&buf_cerr);
172 cerr.flags(ios_base::unitbuf);
174 #ifdef _GLIBCPP_USE_WCHAR_T
175 new (&buf_wcout) wfilebuf(stdout, ios_base::out, __out_bufsize);
176 new (&buf_wcin) wfilebuf(stdin, ios_base::in, __in_bufsize);
177 new (&buf_wcerr) wfilebuf(stderr, ios_base::out, __out_bufsize);
178 new (&wcout) wostream(&buf_wcout);
179 new (&wcin) wistream(&buf_wcin);
180 new (&wcerr) wostream(&buf_wcerr);
181 new (&wclog) wostream(&buf_wcerr);
183 wcerr.flags(ios_base::unitbuf);
188 ios_base::Init::_S_ios_destroy()
190 // Explicitly call dtors to free any memory that is dynamically
191 // allocated by filebuf ctor or member functions, but don't
192 // deallocate all memory by calling operator delete.
196 #ifdef _GLIBCPP_USE_WCHAR_T
197 buf_wcout.~wfilebuf();
198 buf_wcin.~wfilebuf();
199 buf_wcerr.~wfilebuf();
203 ios_base::Init::Init()
205 if (_S_ios_base_init == 0)
207 // Standard streams default to synced with "C" operations.
208 ios_base::Init::_S_synced_with_stdio = true;
209 _S_ios_create(ios_base::Init::_S_synced_with_stdio);
214 ios_base::Init::~Init()
216 if (--_S_ios_base_init == 0)
220 // 27.4.2.5 ios_base storage functions
222 ios_base::xalloc() throw()
224 // Implementation note: Initialize top to zero to ensure that
225 // initialization occurs before main() is started.
226 static _Atomic_word _S_top = 0;
227 return __exchange_and_add(&_S_top, 1) + 4;
230 // 27.4.2.5 iword/pword storage
232 ios_base::_M_grow_words(int ix)
234 // Precondition: _M_word_size <= ix
235 int newsize = _S_local_word_size;
236 _Words* words = _M_local_word;
238 if (ix > _S_local_word_size - 1)
240 const int max = numeric_limits<int>::max();
247 { words = new _Words[newsize]; }
252 _M_streambuf_state |= badbit;
253 if (_M_streambuf_state & _M_exception)
254 __throw_ios_failure("ios_base::_M_grow_words caused exception");
257 for (; i < _M_word_size; i++)
258 words[i] = _M_word[i];
259 if (_M_word && _M_word != _M_local_word)
266 _M_word_size = newsize;
270 // Called only by basic_ios<>::init.
274 // NB: May be called more than once
277 _M_flags = skipws | dec;
280 _M_ios_locale = locale();
283 // 27.4.2.3 ios_base locale functions
285 ios_base::imbue(const locale& __loc)
287 locale __old = _M_ios_locale;
288 _M_ios_locale = __loc;
289 _M_call_callbacks(imbue_event);
293 ios_base::ios_base() : _M_callbacks(0), _M_word(0)
295 // Do nothing: basic_ios::init() does it.
296 // NB: _M_callbacks and _M_word must be zero for non-initialized
297 // ios_base to go through ~ios_base gracefully.
300 // 27.4.2.7 ios_base constructors/destructors
301 ios_base::~ios_base()
303 _M_call_callbacks(erase_event);
304 _M_dispose_callbacks();
305 if (_M_word && _M_word != _M_local_word)
313 ios_base::register_callback(event_callback __fn, int __index)
314 { _M_callbacks = new _Callback_list(__fn, __index, _M_callbacks); }
317 ios_base::_M_call_callbacks(event __e) throw()
319 _Callback_list* __p = _M_callbacks;
323 { (*__p->_M_fn) (__e, *this, __p->_M_index); }
331 ios_base::_M_dispose_callbacks(void)
333 _Callback_list* __p = _M_callbacks;
334 while (__p && __p->_M_remove_reference() == 0)
336 _Callback_list* __next = __p->_M_next;
344 ios_base::sync_with_stdio(bool __sync)
346 #ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS
347 // 49. Underspecification of ios_base::sync_with_stdio
348 bool __ret = ios_base::Init::_S_synced_with_stdio;
351 // Turn off sync with C FILE* for cin, cout, cerr, clog iff
352 // currently synchronized.
353 if (!__sync && __ret)
355 ios_base::Init::_S_synced_with_stdio = false;
356 ios_base::Init::_S_ios_destroy();
357 ios_base::Init::_S_ios_create(ios_base::Init::_S_synced_with_stdio);