contrib/gcc-8.0/libstdc++-v3/include/ext/pod_char_traits.h

   1 // POD character, std::char_traits specialization -*- C++ -*-
   2
   3 // Copyright (C) 2002-2018 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 #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;
  54       typedef character<_Value, _Int, _St>      char_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,
  79                const character<_Value, _Int, _St>& rhs)
  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     {
  99       typedef __gnu_cxx::character<_Value, _Int, _St>   char_type;
 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