libstdc++
pod_char_traits.h
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1// POD character, std::char_traits specialization -*- C++ -*-
2
3// Copyright (C) 2002-2021 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 ext/pod_char_traits.h
26 * This file is a GNU extension to the Standard C++ Library.
27 */
28
29// Gabriel Dos Reis <[email protected]>
30// Benjamin Kosnik <[email protected]>
31
32#ifndef _POD_CHAR_TRAITS_H
33#define _POD_CHAR_TRAITS_H 1
34
35#pragma GCC system_header
36
37#include <string>
38
39namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
40{
41_GLIBCXX_BEGIN_NAMESPACE_VERSION
42
43 // POD character abstraction.
44 // NB: The char_type parameter is a subset of int_type, as to allow
45 // int_type to properly hold the full range of char_type values as
46 // well as EOF.
47 /// @brief A POD class that serves as a character abstraction class.
48 template<typename _Value, typename _Int, typename _St = std::mbstate_t>
49 struct character
50 {
51 typedef _Value value_type;
52 typedef _Int int_type;
53 typedef _St state_type;
55
56 value_type value;
57
58 template<typename V2>
59 static char_type
60 from(const V2& v)
61 {
62 char_type ret = { static_cast<value_type>(v) };
63 return ret;
64 }
65
66 template<typename V2>
67 static V2
68 to(const char_type& c)
69 {
70 V2 ret = { static_cast<V2>(c.value) };
71 return ret;
72 }
73
74 };
75
76 template<typename _Value, typename _Int, typename _St>
77 inline bool
78 operator==(const character<_Value, _Int, _St>& lhs,
80 { return lhs.value == rhs.value; }
81
82 template<typename _Value, typename _Int, typename _St>
83 inline bool
84 operator<(const character<_Value, _Int, _St>& lhs,
85 const character<_Value, _Int, _St>& rhs)
86 { return lhs.value < rhs.value; }
87
88_GLIBCXX_END_NAMESPACE_VERSION
89} // namespace
90
91namespace std _GLIBCXX_VISIBILITY(default)
92{
93_GLIBCXX_BEGIN_NAMESPACE_VERSION
94
95 /// char_traits<__gnu_cxx::character> specialization.
96 template<typename _Value, typename _Int, typename _St>
97 struct char_traits<__gnu_cxx::character<_Value, _Int, _St> >
98 {
100 typedef typename char_type::int_type int_type;
101 typedef typename char_type::state_type state_type;
103 typedef streamoff off_type;
104
105 static void
106 assign(char_type& __c1, const char_type& __c2)
107 { __c1 = __c2; }
108
109 static bool
110 eq(const char_type& __c1, const char_type& __c2)
111 { return __c1 == __c2; }
112
113 static bool
114 lt(const char_type& __c1, const char_type& __c2)
115 { return __c1 < __c2; }
116
117 static int
118 compare(const char_type* __s1, const char_type* __s2, size_t __n)
119 {
120 for (size_t __i = 0; __i < __n; ++__i)
121 if (!eq(__s1[__i], __s2[__i]))
122 return lt(__s1[__i], __s2[__i]) ? -1 : 1;
123 return 0;
124 }
125
126 static size_t
127 length(const char_type* __s)
128 {
129 const char_type* __p = __s;
130 while (__p->value)
131 ++__p;
132 return (__p - __s);
133 }
134
135 static const char_type*
136 find(const char_type* __s, size_t __n, const char_type& __a)
137 {
138 for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
139 if (*__p == __a)
140 return __p;
141 return 0;
142 }
143
144 static char_type*
145 move(char_type* __s1, const char_type* __s2, size_t __n)
146 {
147 if (__n == 0)
148 return __s1;
149 return static_cast<char_type*>
150 (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
151 }
152
153 static char_type*
154 copy(char_type* __s1, const char_type* __s2, size_t __n)
155 {
156 if (__n == 0)
157 return __s1;
158 std::copy(__s2, __s2 + __n, __s1);
159 return __s1;
160 }
161
162 static char_type*
163 assign(char_type* __s, size_t __n, char_type __a)
164 {
165 std::fill_n(__s, __n, __a);
166 return __s;
167 }
168
169 static char_type
170 to_char_type(const int_type& __i)
171 { return char_type::template from(__i); }
172
173 static int_type
174 to_int_type(const char_type& __c)
175 { return char_type::template to<int_type>(__c); }
176
177 static bool
178 eq_int_type(const int_type& __c1, const int_type& __c2)
179 { return __c1 == __c2; }
180
181 static int_type
182 eof()
183 {
184 int_type __r = { static_cast<typename __gnu_cxx::__conditional_type
185 <std::__is_integer<int_type>::__value,
186 int_type, int>::__type>(-1) };
187 return __r;
188 }
189
190 static int_type
191 not_eof(const int_type& __c)
192 { return eq_int_type(__c, eof()) ? int_type() : __c; }
193 };
194
195_GLIBCXX_END_NAMESPACE_VERSION
196} // namespace
197
198#endif
ISO C++ entities toplevel namespace is std.
long long streamoff
Type used by fpos, char_traits<char>, and char_traits<wchar_t>.
Definition: postypes.h:94
GNU extensions for public use.
Basis for explicit traits specializations.
Definition: char_traits.h:339
Class representing stream positions.
Definition: postypes.h:113
A POD class that serves as a character abstraction class.