libstdc++

basic_ios.tcc
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1 // basic_ios member functions -*- C++ -*-
2
3 // Copyright (C) 1999-2013 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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24
25 /** @file bits/basic_ios.tcc
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{ios}
28 */
29
30 #ifndef _BASIC_IOS_TCC
31 #define _BASIC_IOS_TCC 1
32
33 #pragma GCC system_header
34
35 namespace std _GLIBCXX_VISIBILITY(default)
36 {
37 _GLIBCXX_BEGIN_NAMESPACE_VERSION
38
39 template<typename _CharT, typename _Traits>
40 void
41 basic_ios<_CharT, _Traits>::clear(iostate __state)
42 {
43 if (this->rdbuf())
44 _M_streambuf_state = __state;
45 else
46 _M_streambuf_state = __state | badbit;
47 if (this->exceptions() & this->rdstate())
48 __throw_ios_failure(__N("basic_ios::clear"));
49 }
50
51 template<typename _CharT, typename _Traits>
52 basic_streambuf<_CharT, _Traits>*
53 basic_ios<_CharT, _Traits>::rdbuf(basic_streambuf<_CharT, _Traits>* __sb)
54 {
55 basic_streambuf<_CharT, _Traits>* __old = _M_streambuf;
56 _M_streambuf = __sb;
57 this->clear();
58 return __old;
59 }
60
61 template<typename _CharT, typename _Traits>
62 basic_ios<_CharT, _Traits>&
63 basic_ios<_CharT, _Traits>::copyfmt(const basic_ios& __rhs)
64 {
65 // _GLIBCXX_RESOLVE_LIB_DEFECTS
66 // 292. effects of a.copyfmt (a)
67 if (this != &__rhs)
68 {
69 // Per 27.1.1, do not call imbue, yet must trash all caches
70 // associated with imbue()
71
72 // Alloc any new word array first, so if it fails we have "rollback".
73 _Words* __words = (__rhs._M_word_size <= _S_local_word_size) ?
74 _M_local_word : new _Words[__rhs._M_word_size];
75
76 // Bump refs before doing callbacks, for safety.
77 _Callback_list* __cb = __rhs._M_callbacks;
78 if (__cb)
79 __cb->_M_add_reference();
80 _M_call_callbacks(erase_event);
81 if (_M_word != _M_local_word)
82 {
83 delete [] _M_word;
84 _M_word = 0;
85 }
86 _M_dispose_callbacks();
87
88 // NB: Don't want any added during above.
89 _M_callbacks = __cb;
90 for (int __i = 0; __i < __rhs._M_word_size; ++__i)
91 __words[__i] = __rhs._M_word[__i];
92 _M_word = __words;
93 _M_word_size = __rhs._M_word_size;
94
95 this->flags(__rhs.flags());
96 this->width(__rhs.width());
97 this->precision(__rhs.precision());
98 this->tie(__rhs.tie());
99 this->fill(__rhs.fill());
100 _M_ios_locale = __rhs.getloc();
101 _M_cache_locale(_M_ios_locale);
102
103 _M_call_callbacks(copyfmt_event);
104
105 // The next is required to be the last assignment.
106 this->exceptions(__rhs.exceptions());
107 }
108 return *this;
109 }
110
111 // Locales:
112 template<typename _CharT, typename _Traits>
113 locale
114 basic_ios<_CharT, _Traits>::imbue(const locale& __loc)
115 {
116 locale __old(this->getloc());
117 ios_base::imbue(__loc);
118 _M_cache_locale(__loc);
119 if (this->rdbuf() != 0)
120 this->rdbuf()->pubimbue(__loc);
121 return __old;
122 }
123
124 template<typename _CharT, typename _Traits>
125 void
126 basic_ios<_CharT, _Traits>::init(basic_streambuf<_CharT, _Traits>* __sb)
127 {
128 // NB: This may be called more than once on the same object.
129 ios_base::_M_init();
130
131 // Cache locale data and specific facets used by iostreams.
132 _M_cache_locale(_M_ios_locale);
133
134 // NB: The 27.4.4.1 Postconditions Table specifies requirements
135 // after basic_ios::init() has been called. As part of this,
136 // fill() must return widen(' ') any time after init() has been
137 // called, which needs an imbued ctype facet of char_type to
138 // return without throwing an exception. Unfortunately,
139 // ctype<char_type> is not necessarily a required facet, so
140 // streams with char_type != [char, wchar_t] will not have it by
141 // default. Because of this, the correct value for _M_fill is
142 // constructed on the first call of fill(). That way,
143 // unformatted input and output with non-required basic_ios
144 // instantiations is possible even without imbuing the expected
145 // ctype<char_type> facet.
146 _M_fill = _CharT();
147 _M_fill_init = false;
148
149 _M_tie = 0;
150 _M_exception = goodbit;
151 _M_streambuf = __sb;
152 _M_streambuf_state = __sb ? goodbit : badbit;
153 }
154
155 template<typename _CharT, typename _Traits>
156 void
157 basic_ios<_CharT, _Traits>::_M_cache_locale(const locale& __loc)
158 {
159 if (__builtin_expect(has_facet<__ctype_type>(__loc), true))
160 _M_ctype = &use_facet<__ctype_type>(__loc);
161 else
162 _M_ctype = 0;
163
164 if (__builtin_expect(has_facet<__num_put_type>(__loc), true))
165 _M_num_put = &use_facet<__num_put_type>(__loc);
166 else
167 _M_num_put = 0;
168
169 if (__builtin_expect(has_facet<__num_get_type>(__loc), true))
170 _M_num_get = &use_facet<__num_get_type>(__loc);
171 else
172 _M_num_get = 0;
173 }
174
175 // Inhibit implicit instantiations for required instantiations,
176 // which are defined via explicit instantiations elsewhere.
177 #if _GLIBCXX_EXTERN_TEMPLATE
178 extern template class basic_ios<char>;
179
180 #ifdef _GLIBCXX_USE_WCHAR_T
181 extern template class basic_ios<wchar_t>;
182 #endif
183 #endif
184
185 _GLIBCXX_END_NAMESPACE_VERSION
186 } // namespace std
187
188 #endif