libstdc++
pod_char_traits.h
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1 // POD character, std::char_traits specialization -*- C++ -*-
2 
3 // Copyright (C) 2002-2013 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 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 V, typename I, typename S = std::mbstate_t>
49  struct character
50  {
51  typedef V value_type;
52  typedef I int_type;
53  typedef S 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 V, typename I, typename S>
77  inline bool
78  operator==(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
79  { return lhs.value == rhs.value; }
80 
81  template<typename V, typename I, typename S>
82  inline bool
83  operator<(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
84  { return lhs.value < rhs.value; }
85 
86 _GLIBCXX_END_NAMESPACE_VERSION
87 } // namespace
88 
89 namespace std _GLIBCXX_VISIBILITY(default)
90 {
91 _GLIBCXX_BEGIN_NAMESPACE_VERSION
92 
93  /// char_traits<__gnu_cxx::character> specialization.
94  template<typename V, typename I, typename S>
95  struct char_traits<__gnu_cxx::character<V, I, S> >
96  {
97  typedef __gnu_cxx::character<V, I, S> char_type;
98  typedef typename char_type::int_type int_type;
99  typedef typename char_type::state_type state_type;
100  typedef fpos<state_type> pos_type;
101  typedef streamoff off_type;
102 
103  static void
104  assign(char_type& __c1, const char_type& __c2)
105  { __c1 = __c2; }
106 
107  static bool
108  eq(const char_type& __c1, const char_type& __c2)
109  { return __c1 == __c2; }
110 
111  static bool
112  lt(const char_type& __c1, const char_type& __c2)
113  { return __c1 < __c2; }
114 
115  static int
116  compare(const char_type* __s1, const char_type* __s2, size_t __n)
117  {
118  for (size_t __i = 0; __i < __n; ++__i)
119  if (!eq(__s1[__i], __s2[__i]))
120  return lt(__s1[__i], __s2[__i]) ? -1 : 1;
121  return 0;
122  }
123 
124  static size_t
125  length(const char_type* __s)
126  {
127  const char_type* __p = __s;
128  while (__p->value)
129  ++__p;
130  return (__p - __s);
131  }
132 
133  static const char_type*
134  find(const char_type* __s, size_t __n, const char_type& __a)
135  {
136  for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
137  if (*__p == __a)
138  return __p;
139  return 0;
140  }
141 
142  static char_type*
143  move(char_type* __s1, const char_type* __s2, size_t __n)
144  {
145  return static_cast<char_type*>
146  (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
147  }
148 
149  static char_type*
150  copy(char_type* __s1, const char_type* __s2, size_t __n)
151  {
152  std::copy(__s2, __s2 + __n, __s1);
153  return __s1;
154  }
155 
156  static char_type*
157  assign(char_type* __s, size_t __n, char_type __a)
158  {
159  std::fill_n(__s, __n, __a);
160  return __s;
161  }
162 
163  static char_type
164  to_char_type(const int_type& __i)
165  { return char_type::template from(__i); }
166 
167  static int_type
168  to_int_type(const char_type& __c)
169  { return char_type::template to<int_type>(__c); }
170 
171  static bool
172  eq_int_type(const int_type& __c1, const int_type& __c2)
173  { return __c1 == __c2; }
174 
175  static int_type
176  eof()
177  {
178  int_type __r = { -1 };
179  return __r;
180  }
181 
182  static int_type
183  not_eof(const int_type& __c)
184  { return eq_int_type(__c, eof()) ? int_type() : __c; }
185  };
186 
187 _GLIBCXX_END_NAMESPACE_VERSION
188 } // namespace
189 
190 #endif
_OI fill_n(_OI __first, _Size __n, const _Tp &__value)
Fills the range [first,first+n) with copies of value.
Definition: stl_algobase.h:781
Class representing stream positions.
Definition: postypes.h:112
Basis for explicit traits specializations.
Definition: char_traits.h:227
long long streamoff
Type used by fpos, char_traits, and char_traits.
Definition: postypes.h:94
A POD class that serves as a character abstraction class.
GNU extensions for public use.
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition: move.h:101
ISO C++ entities toplevel namespace is std.