libstdc++
pod_char_traits.h
Go to the documentation of this file.
1 // POD character, std::char_traits specialization -*- C++ -*-
2 
3 // Copyright (C) 2002, 2003, 2004, 2005, 2007, 2009 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 <gdr@integrable-solutions.net>
30 // Benjamin Kosnik <bkoz@redhat.com>
31 
32 #ifndef _POD_CHAR_TRAITS_H
33 #define _POD_CHAR_TRAITS_H 1
34 
35 #include <string>
36 
37 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
38 {
39 _GLIBCXX_BEGIN_NAMESPACE_VERSION
40 
41  // POD character abstraction.
42  // NB: The char_type parameter is a subset of int_type, as to allow
43  // int_type to properly hold the full range of char_type values as
44  // well as EOF.
45  /// @brief A POD class that serves as a character abstraction class.
46  template<typename V, typename I, typename S = std::mbstate_t>
47  struct character
48  {
49  typedef V value_type;
50  typedef I int_type;
51  typedef S state_type;
53 
54  value_type value;
55 
56  template<typename V2>
57  static char_type
58  from(const V2& v)
59  {
60  char_type ret = { static_cast<value_type>(v) };
61  return ret;
62  }
63 
64  template<typename V2>
65  static V2
66  to(const char_type& c)
67  {
68  V2 ret = { static_cast<V2>(c.value) };
69  return ret;
70  }
71 
72  };
73 
74  template<typename V, typename I, typename S>
75  inline bool
76  operator==(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
77  { return lhs.value == rhs.value; }
78 
79  template<typename V, typename I, typename S>
80  inline bool
81  operator<(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
82  { return lhs.value < rhs.value; }
83 
84 _GLIBCXX_END_NAMESPACE_VERSION
85 } // namespace
86 
87 namespace std _GLIBCXX_VISIBILITY(default)
88 {
89 _GLIBCXX_BEGIN_NAMESPACE_VERSION
90 
91  /// char_traits<__gnu_cxx::character> specialization.
92  template<typename V, typename I, typename S>
93  struct char_traits<__gnu_cxx::character<V, I, S> >
94  {
96  typedef typename char_type::int_type int_type;
97  typedef typename char_type::state_type state_type;
98  typedef fpos<state_type> pos_type;
99  typedef streamoff off_type;
100 
101  static void
102  assign(char_type& __c1, const char_type& __c2)
103  { __c1 = __c2; }
104 
105  static bool
106  eq(const char_type& __c1, const char_type& __c2)
107  { return __c1 == __c2; }
108 
109  static bool
110  lt(const char_type& __c1, const char_type& __c2)
111  { return __c1 < __c2; }
112 
113  static int
114  compare(const char_type* __s1, const char_type* __s2, size_t __n)
115  {
116  for (size_t __i = 0; __i < __n; ++__i)
117  if (!eq(__s1[__i], __s2[__i]))
118  return lt(__s1[__i], __s2[__i]) ? -1 : 1;
119  return 0;
120  }
121 
122  static size_t
123  length(const char_type* __s)
124  {
125  const char_type* __p = __s;
126  while (__p->value)
127  ++__p;
128  return (__p - __s);
129  }
130 
131  static const char_type*
132  find(const char_type* __s, size_t __n, const char_type& __a)
133  {
134  for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
135  if (*__p == __a)
136  return __p;
137  return 0;
138  }
139 
140  static char_type*
141  move(char_type* __s1, const char_type* __s2, size_t __n)
142  {
143  return static_cast<char_type*>
144  (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
145  }
146 
147  static char_type*
148  copy(char_type* __s1, const char_type* __s2, size_t __n)
149  {
150  std::copy(__s2, __s2 + __n, __s1);
151  return __s1;
152  }
153 
154  static char_type*
155  assign(char_type* __s, size_t __n, char_type __a)
156  {
157  std::fill_n(__s, __n, __a);
158  return __s;
159  }
160 
161  static char_type
162  to_char_type(const int_type& __i)
163  { return char_type::template from(__i); }
164 
165  static int_type
166  to_int_type(const char_type& __c)
167  { return char_type::template to<int_type>(__c); }
168 
169  static bool
170  eq_int_type(const int_type& __c1, const int_type& __c2)
171  { return __c1 == __c2; }
172 
173  static int_type
174  eof()
175  {
176  int_type __r = { -1 };
177  return __r;
178  }
179 
180  static int_type
181  not_eof(const int_type& __c)
182  { return eq_int_type(__c, eof()) ? int_type() : __c; }
183  };
184 
185 _GLIBCXX_END_NAMESPACE_VERSION
186 } // namespace
187 
188 #endif