libstdc++
basic_ios.tcc
Go to the documentation of this file.
1 // basic_ios member functions -*- C++ -*-
2 
3 // Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
4 // 2009, 2010, 2011 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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
20 
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
25 
26 /** @file bits/basic_ios.tcc
27  * This is an internal header file, included by other library headers.
28  * Do not attempt to use it directly. @headername{ios}
29  */
30 
31 #ifndef _BASIC_IOS_TCC
32 #define _BASIC_IOS_TCC 1
33 
34 #pragma GCC system_header
35 
36 namespace std _GLIBCXX_VISIBILITY(default)
37 {
38 _GLIBCXX_BEGIN_NAMESPACE_VERSION
39 
40  template<typename _CharT, typename _Traits>
41  void
43  {
44  if (this->rdbuf())
45  _M_streambuf_state = __state;
46  else
47  _M_streambuf_state = __state | badbit;
48  if (this->exceptions() & this->rdstate())
49  __throw_ios_failure(__N("basic_ios::clear"));
50  }
51 
52  template<typename _CharT, typename _Traits>
55  {
56  basic_streambuf<_CharT, _Traits>* __old = _M_streambuf;
57  _M_streambuf = __sb;
58  this->clear();
59  return __old;
60  }
61 
62  template<typename _CharT, typename _Traits>
65  {
66  // _GLIBCXX_RESOLVE_LIB_DEFECTS
67  // 292. effects of a.copyfmt (a)
68  if (this != &__rhs)
69  {
70  // Per 27.1.1, do not call imbue, yet must trash all caches
71  // associated with imbue()
72 
73  // Alloc any new word array first, so if it fails we have "rollback".
74  _Words* __words = (__rhs._M_word_size <= _S_local_word_size) ?
75  _M_local_word : new _Words[__rhs._M_word_size];
76 
77  // Bump refs before doing callbacks, for safety.
78  _Callback_list* __cb = __rhs._M_callbacks;
79  if (__cb)
80  __cb->_M_add_reference();
81  _M_call_callbacks(erase_event);
82  if (_M_word != _M_local_word)
83  {
84  delete [] _M_word;
85  _M_word = 0;
86  }
87  _M_dispose_callbacks();
88 
89  // NB: Don't want any added during above.
90  _M_callbacks = __cb;
91  for (int __i = 0; __i < __rhs._M_word_size; ++__i)
92  __words[__i] = __rhs._M_word[__i];
93  _M_word = __words;
94  _M_word_size = __rhs._M_word_size;
95 
96  this->flags(__rhs.flags());
97  this->width(__rhs.width());
98  this->precision(__rhs.precision());
99  this->tie(__rhs.tie());
100  this->fill(__rhs.fill());
101  _M_ios_locale = __rhs.getloc();
102  _M_cache_locale(_M_ios_locale);
103 
104  _M_call_callbacks(copyfmt_event);
105 
106  // The next is required to be the last assignment.
107  this->exceptions(__rhs.exceptions());
108  }
109  return *this;
110  }
111 
112  // Locales:
113  template<typename _CharT, typename _Traits>
114  locale
116  {
117  locale __old(this->getloc());
118  ios_base::imbue(__loc);
119  _M_cache_locale(__loc);
120  if (this->rdbuf() != 0)
121  this->rdbuf()->pubimbue(__loc);
122  return __old;
123  }
124 
125  template<typename _CharT, typename _Traits>
126  void
128  {
129  // NB: This may be called more than once on the same object.
130  ios_base::_M_init();
131 
132  // Cache locale data and specific facets used by iostreams.
133  _M_cache_locale(_M_ios_locale);
134 
135  // NB: The 27.4.4.1 Postconditions Table specifies requirements
136  // after basic_ios::init() has been called. As part of this,
137  // fill() must return widen(' ') any time after init() has been
138  // called, which needs an imbued ctype facet of char_type to
139  // return without throwing an exception. Unfortunately,
140  // ctype<char_type> is not necessarily a required facet, so
141  // streams with char_type != [char, wchar_t] will not have it by
142  // default. Because of this, the correct value for _M_fill is
143  // constructed on the first call of fill(). That way,
144  // unformatted input and output with non-required basic_ios
145  // instantiations is possible even without imbuing the expected
146  // ctype<char_type> facet.
147  _M_fill = _CharT();
148  _M_fill_init = false;
149 
150  _M_tie = 0;
151  _M_exception = goodbit;
152  _M_streambuf = __sb;
153  _M_streambuf_state = __sb ? goodbit : badbit;
154  }
155 
156  template<typename _CharT, typename _Traits>
157  void
159  {
160  if (__builtin_expect(has_facet<__ctype_type>(__loc), true))
161  _M_ctype = &use_facet<__ctype_type>(__loc);
162  else
163  _M_ctype = 0;
164 
165  if (__builtin_expect(has_facet<__num_put_type>(__loc), true))
166  _M_num_put = &use_facet<__num_put_type>(__loc);
167  else
168  _M_num_put = 0;
169 
170  if (__builtin_expect(has_facet<__num_get_type>(__loc), true))
171  _M_num_get = &use_facet<__num_get_type>(__loc);
172  else
173  _M_num_get = 0;
174  }
175 
176  // Inhibit implicit instantiations for required instantiations,
177  // which are defined via explicit instantiations elsewhere.
178 #if _GLIBCXX_EXTERN_TEMPLATE
179  extern template class basic_ios<char>;
180 
181 #ifdef _GLIBCXX_USE_WCHAR_T
182  extern template class basic_ios<wchar_t>;
183 #endif
184 #endif
185 
186 _GLIBCXX_END_NAMESPACE_VERSION
187 } // namespace std
188 
189 #endif
locale imbue(const locale &__loc)
Setting a new locale.
Virtual base class for all stream classes.Most of the member functions called dispatched on stream ob...
Definition: iosfwd:79
iostate exceptions() const
Throwing exceptions on errors.
Definition: basic_ios.h:214
char_type fill() const
Retrieves the empty character.
Definition: basic_ios.h:362
basic_ostream< _CharT, _Traits > * tie() const
Fetches the current tied stream.
Definition: basic_ios.h:287
streamsize width() const
Flags access.
Definition: ios_base.h:646
void init(basic_streambuf< _CharT, _Traits > *__sb)
All setup is performed here.
Definition: basic_ios.tcc:127
Container class for localization functionality.The locale class is first a class wrapper for C librar...
locale imbue(const locale &__loc)
Moves to a new locale.
Definition: basic_ios.tcc:115
fmtflags flags() const
Access to format flags.
Definition: ios_base.h:553
streamsize precision() const
Flags access.
Definition: ios_base.h:623
basic_streambuf< _CharT, _Traits > * rdbuf() const
Accessing the underlying buffer.
Definition: basic_ios.h:313
void clear(iostate __state=goodbit)
[Re]sets the error state.
Definition: basic_ios.tcc:42
The actual work of input and output (interface).This is a base class. Derived stream buffers each con...
Definition: iosfwd:82
locale getloc() const
Locale access.
Definition: ios_base.h:697
basic_ios & copyfmt(const basic_ios &__rhs)
Copies fields of __rhs into this.
Definition: basic_ios.tcc:64