libstdc++
pod_char_traits.h
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00001 // POD character, std::char_traits specialization -*- C++ -*-
00002 
00003 // Copyright (C) 2002-2015 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /** @file ext/pod_char_traits.h
00026  *  This file is a GNU extension to the Standard C++ Library.
00027  */
00028 
00029 // Gabriel Dos Reis <gdr@integrable-solutions.net>
00030 // Benjamin Kosnik <bkoz@redhat.com>
00031 
00032 #ifndef _POD_CHAR_TRAITS_H
00033 #define _POD_CHAR_TRAITS_H 1
00034 
00035 #pragma GCC system_header
00036 
00037 #include <string>
00038 
00039 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
00040 {
00041 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00042 
00043   // POD character abstraction.
00044   // NB: The char_type parameter is a subset of int_type, as to allow
00045   // int_type to properly hold the full range of char_type values as
00046   // well as EOF.
00047   /// @brief A POD class that serves as a character abstraction class.
00048   template<typename _Value, typename _Int, typename _St = std::mbstate_t>
00049     struct character
00050     {
00051       typedef _Value                            value_type;
00052       typedef _Int                              int_type;
00053       typedef _St                               state_type;
00054       typedef character<_Value, _Int, _St>      char_type;
00055 
00056       value_type        value;
00057 
00058       template<typename V2>
00059         static char_type
00060         from(const V2& v)
00061         {
00062           char_type ret = { static_cast<value_type>(v) };
00063           return ret;
00064         }
00065 
00066       template<typename V2>
00067         static V2
00068         to(const char_type& c)
00069         {
00070           V2 ret = { static_cast<V2>(c.value) };
00071           return ret;
00072         }
00073 
00074     };
00075 
00076   template<typename _Value, typename _Int, typename _St>
00077     inline bool
00078     operator==(const character<_Value, _Int, _St>& lhs,
00079                const character<_Value, _Int, _St>& rhs)
00080     { return lhs.value == rhs.value; }
00081 
00082   template<typename _Value, typename _Int, typename _St>
00083     inline bool
00084     operator<(const character<_Value, _Int, _St>& lhs,
00085               const character<_Value, _Int, _St>& rhs)
00086     { return lhs.value < rhs.value; }
00087 
00088 _GLIBCXX_END_NAMESPACE_VERSION
00089 } // namespace
00090 
00091 namespace std _GLIBCXX_VISIBILITY(default)
00092 {
00093 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00094 
00095   /// char_traits<__gnu_cxx::character> specialization.
00096   template<typename _Value, typename _Int, typename _St>
00097     struct char_traits<__gnu_cxx::character<_Value, _Int, _St> >
00098     {
00099       typedef __gnu_cxx::character<_Value, _Int, _St>   char_type;
00100       typedef typename char_type::int_type              int_type;
00101       typedef typename char_type::state_type            state_type;
00102       typedef fpos<state_type>                          pos_type;
00103       typedef streamoff                                 off_type;
00104 
00105       static void
00106       assign(char_type& __c1, const char_type& __c2)
00107       { __c1 = __c2; }
00108 
00109       static bool
00110       eq(const char_type& __c1, const char_type& __c2)
00111       { return __c1 == __c2; }
00112 
00113       static bool
00114       lt(const char_type& __c1, const char_type& __c2)
00115       { return __c1 < __c2; }
00116 
00117       static int
00118       compare(const char_type* __s1, const char_type* __s2, size_t __n)
00119       {
00120         for (size_t __i = 0; __i < __n; ++__i)
00121           if (!eq(__s1[__i], __s2[__i]))
00122             return lt(__s1[__i], __s2[__i]) ? -1 : 1;
00123         return 0;
00124       }
00125 
00126       static size_t
00127       length(const char_type* __s)
00128       {
00129         const char_type* __p = __s;
00130         while (__p->value)
00131           ++__p;
00132         return (__p - __s);
00133       }
00134 
00135       static const char_type*
00136       find(const char_type* __s, size_t __n, const char_type& __a)
00137       {
00138         for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
00139           if (*__p == __a)
00140             return __p;
00141         return 0;
00142       }
00143 
00144       static char_type*
00145       move(char_type* __s1, const char_type* __s2, size_t __n)
00146       { 
00147         if (__n == 0)
00148           return __s1;
00149         return static_cast<char_type*>
00150           (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
00151       }
00152 
00153       static char_type*
00154       copy(char_type* __s1, const char_type* __s2, size_t __n)
00155       {
00156         if (__n == 0)
00157           return __s1;
00158         std::copy(__s2, __s2 + __n, __s1);
00159         return __s1;
00160       }
00161 
00162       static char_type*
00163       assign(char_type* __s, size_t __n, char_type __a)
00164       {
00165         std::fill_n(__s, __n, __a);
00166         return __s;
00167       }
00168 
00169       static char_type
00170       to_char_type(const int_type& __i)
00171       { return char_type::template from(__i); }
00172 
00173       static int_type
00174       to_int_type(const char_type& __c)
00175       { return char_type::template to<int_type>(__c); }
00176 
00177       static bool
00178       eq_int_type(const int_type& __c1, const int_type& __c2)
00179       { return __c1 == __c2; }
00180 
00181       static int_type
00182       eof() 
00183       {
00184         int_type __r = { static_cast<typename __gnu_cxx::__conditional_type
00185                          <std::__is_integer<int_type>::__value,
00186                          int_type, int>::__type>(-1) };
00187         return __r;
00188       }
00189 
00190       static int_type
00191       not_eof(const int_type& __c)
00192       { return eq_int_type(__c, eof()) ? int_type() : __c; }
00193     };
00194 
00195 _GLIBCXX_END_NAMESPACE_VERSION
00196 } // namespace
00197 
00198 #endif