libstdc++
basic_ios.tcc
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1// basic_ios member functions -*- C++ -*-
2
3// Copyright (C) 1999-2022 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
35namespace std _GLIBCXX_VISIBILITY(default)
36{
37_GLIBCXX_BEGIN_NAMESPACE_VERSION
38
39 template<typename _CharT, typename _Traits>
40 void
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>
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>
64 {
65 // _GLIBCXX_RESOLVE_LIB_DEFECTS
66 // 292. effects of a.copyfmt (a)
67 if (this != std::__addressof(__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
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
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;
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
158 {
159 if (__builtin_expect(has_facet<__ctype_type>(__loc), true))
160 _M_ctype = std::__addressof(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 = std::__addressof(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 = std::__addressof(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
constexpr tuple< _Elements &... > tie(_Elements &... __args) noexcept
tie
Definition: tuple:2152
constexpr _Tp * __addressof(_Tp &__r) noexcept
Same as C++11 std::addressof.
Definition: move.h:49
ISO C++ entities toplevel namespace is std.
Template class basic_ios, virtual base class for all stream classes.
Definition: basic_ios.h:68
void clear(iostate __state=goodbit)
[Re]sets the error state.
Definition: basic_ios.tcc:41
locale imbue(const locale &__loc)
Moves to a new locale.
Definition: basic_ios.tcc:114
basic_ostream< _CharT, _Traits > * tie() const
Fetches the current tied stream.
Definition: basic_ios.h:295
iostate exceptions() const
Throwing exceptions on errors.
Definition: basic_ios.h:222
basic_ios & copyfmt(const basic_ios &__rhs)
Copies fields of __rhs into this.
Definition: basic_ios.tcc:63
void init(basic_streambuf< _CharT, _Traits > *__sb)
All setup is performed here.
Definition: basic_ios.tcc:126
char_type fill() const
Retrieves the empty character.
Definition: basic_ios.h:370
basic_streambuf< _CharT, _Traits > * rdbuf() const
Accessing the underlying buffer.
Definition: basic_ios.h:321
The actual work of input and output (interface).
Definition: streambuf:125
streamsize precision() const
Flags access.
Definition: ios_base.h:732
locale imbue(const locale &__loc)
Setting a new locale.
fmtflags flags() const
Access to format flags.
Definition: ios_base.h:662
streamsize width() const
Flags access.
Definition: ios_base.h:755
locale getloc() const
Locale access.
Definition: ios_base.h:806
Container class for localization functionality.