libstdc++
pod_char_traits.h
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1 // POD character, std::char_traits specialization -*- C++ -*-
2 
3 // Copyright (C) 2002-2020 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 
39 namespace __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 
91 namespace 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;
102  typedef fpos<state_type> pos_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.