libstdc++
pod_char_traits.h
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1 // POD character, std::char_traits specialization -*- C++ -*-
2 
3 // Copyright (C) 2002, 2003, 2004, 2005, 2007, 2009, 2010, 2011
4 // Free Software Foundation, Inc.
5 //
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
10 // any later version.
11 
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16 
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
20 
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
25 
26 /** @file ext/pod_char_traits.h
27  * This file is a GNU extension to the Standard C++ Library.
28  */
29 
30 // Gabriel Dos Reis <gdr@integrable-solutions.net>
31 // Benjamin Kosnik <bkoz@redhat.com>
32 
33 #ifndef _POD_CHAR_TRAITS_H
34 #define _POD_CHAR_TRAITS_H 1
35 
36 #pragma GCC system_header
37 
38 #include <string>
39 
40 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
41 {
42 _GLIBCXX_BEGIN_NAMESPACE_VERSION
43 
44  // POD character abstraction.
45  // NB: The char_type parameter is a subset of int_type, as to allow
46  // int_type to properly hold the full range of char_type values as
47  // well as EOF.
48  /// @brief A POD class that serves as a character abstraction class.
49  template<typename V, typename I, typename S = std::mbstate_t>
50  struct character
51  {
52  typedef V value_type;
53  typedef I int_type;
54  typedef S state_type;
56 
57  value_type value;
58 
59  template<typename V2>
60  static char_type
61  from(const V2& v)
62  {
63  char_type ret = { static_cast<value_type>(v) };
64  return ret;
65  }
66 
67  template<typename V2>
68  static V2
69  to(const char_type& c)
70  {
71  V2 ret = { static_cast<V2>(c.value) };
72  return ret;
73  }
74 
75  };
76 
77  template<typename V, typename I, typename S>
78  inline bool
79  operator==(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
80  { return lhs.value == rhs.value; }
81 
82  template<typename V, typename I, typename S>
83  inline bool
84  operator<(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
85  { return lhs.value < rhs.value; }
86 
87 _GLIBCXX_END_NAMESPACE_VERSION
88 } // namespace
89 
90 namespace std _GLIBCXX_VISIBILITY(default)
91 {
92 _GLIBCXX_BEGIN_NAMESPACE_VERSION
93 
94  /// char_traits<__gnu_cxx::character> specialization.
95  template<typename V, typename I, typename S>
96  struct char_traits<__gnu_cxx::character<V, I, S> >
97  {
99  typedef typename char_type::int_type int_type;
100  typedef typename char_type::state_type state_type;
101  typedef fpos<state_type> pos_type;
102  typedef streamoff off_type;
103 
104  static void
105  assign(char_type& __c1, const char_type& __c2)
106  { __c1 = __c2; }
107 
108  static bool
109  eq(const char_type& __c1, const char_type& __c2)
110  { return __c1 == __c2; }
111 
112  static bool
113  lt(const char_type& __c1, const char_type& __c2)
114  { return __c1 < __c2; }
115 
116  static int
117  compare(const char_type* __s1, const char_type* __s2, size_t __n)
118  {
119  for (size_t __i = 0; __i < __n; ++__i)
120  if (!eq(__s1[__i], __s2[__i]))
121  return lt(__s1[__i], __s2[__i]) ? -1 : 1;
122  return 0;
123  }
124 
125  static size_t
126  length(const char_type* __s)
127  {
128  const char_type* __p = __s;
129  while (__p->value)
130  ++__p;
131  return (__p - __s);
132  }
133 
134  static const char_type*
135  find(const char_type* __s, size_t __n, const char_type& __a)
136  {
137  for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
138  if (*__p == __a)
139  return __p;
140  return 0;
141  }
142 
143  static char_type*
144  move(char_type* __s1, const char_type* __s2, size_t __n)
145  {
146  return static_cast<char_type*>
147  (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
148  }
149 
150  static char_type*
151  copy(char_type* __s1, const char_type* __s2, size_t __n)
152  {
153  std::copy(__s2, __s2 + __n, __s1);
154  return __s1;
155  }
156 
157  static char_type*
158  assign(char_type* __s, size_t __n, char_type __a)
159  {
160  std::fill_n(__s, __n, __a);
161  return __s;
162  }
163 
164  static char_type
165  to_char_type(const int_type& __i)
166  { return char_type::template from(__i); }
167 
168  static int_type
169  to_int_type(const char_type& __c)
170  { return char_type::template to<int_type>(__c); }
171 
172  static bool
173  eq_int_type(const int_type& __c1, const int_type& __c2)
174  { return __c1 == __c2; }
175 
176  static int_type
177  eof()
178  {
179  int_type __r = { -1 };
180  return __r;
181  }
182 
183  static int_type
184  not_eof(const int_type& __c)
185  { return eq_int_type(__c, eof()) ? int_type() : __c; }
186  };
187 
188 _GLIBCXX_END_NAMESPACE_VERSION
189 } // namespace
190 
191 #endif