pod_char_traits.h

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00001 // POD character, std::char_traits specialization -*- C++ -*-
00002 
00003 // Copyright (C) 2002, 2003, 2004, 2005, 2007, 2009 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 #include <string>
00036 
00037 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
00038 
00039   // POD character abstraction.
00040   // NB: The char_type parameter is a subset of int_type, as to allow
00041   // int_type to properly hold the full range of char_type values as
00042   // well as EOF.
00043   /// @brief A POD class that serves as a character abstraction class.
00044   template<typename V, typename I, typename S = std::mbstate_t>
00045     struct character
00046     {
00047       typedef V             value_type;
00048       typedef I             int_type;
00049       typedef S             state_type;
00050       typedef character<V, I, S>    char_type;
00051 
00052       value_type    value;
00053 
00054       template<typename V2>
00055         static char_type
00056         from(const V2& v)
00057         {
00058       char_type ret = { static_cast<value_type>(v) };
00059       return ret;
00060     }
00061 
00062       template<typename V2>
00063         static V2
00064         to(const char_type& c)
00065         {
00066       V2 ret = { static_cast<V2>(c.value) };
00067       return ret;
00068     }
00069 
00070     };
00071 
00072   template<typename V, typename I, typename S>
00073     inline bool
00074     operator==(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
00075     { return lhs.value == rhs.value; }
00076 
00077   template<typename V, typename I, typename S>
00078     inline bool
00079     operator<(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
00080     { return lhs.value < rhs.value; }
00081 
00082 _GLIBCXX_END_NAMESPACE
00083 
00084 _GLIBCXX_BEGIN_NAMESPACE(std)
00085 
00086   /// char_traits<__gnu_cxx::character> specialization.
00087   template<typename V, typename I, typename S>
00088     struct char_traits<__gnu_cxx::character<V, I, S> >
00089     {
00090       typedef __gnu_cxx::character<V, I, S> char_type;
00091       typedef typename char_type::int_type  int_type;
00092       typedef typename char_type::state_type    state_type;
00093       typedef fpos<state_type>          pos_type;
00094       typedef streamoff             off_type;
00095 
00096       static void
00097       assign(char_type& __c1, const char_type& __c2)
00098       { __c1 = __c2; }
00099 
00100       static bool
00101       eq(const char_type& __c1, const char_type& __c2)
00102       { return __c1 == __c2; }
00103 
00104       static bool
00105       lt(const char_type& __c1, const char_type& __c2)
00106       { return __c1 < __c2; }
00107 
00108       static int
00109       compare(const char_type* __s1, const char_type* __s2, size_t __n)
00110       {
00111     for (size_t __i = 0; __i < __n; ++__i)
00112       if (!eq(__s1[__i], __s2[__i]))
00113         return lt(__s1[__i], __s2[__i]) ? -1 : 1;
00114     return 0;
00115       }
00116 
00117       static size_t
00118       length(const char_type* __s)
00119       {
00120     const char_type* __p = __s;
00121     while (__p->value)
00122       ++__p;
00123     return (__p - __s);
00124       }
00125 
00126       static const char_type*
00127       find(const char_type* __s, size_t __n, const char_type& __a)
00128       {
00129     for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
00130       if (*__p == __a)
00131         return __p;
00132     return 0;
00133       }
00134 
00135       static char_type*
00136       move(char_type* __s1, const char_type* __s2, size_t __n)
00137       { 
00138     return static_cast<char_type*>
00139       (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
00140       }
00141 
00142       static char_type*
00143       copy(char_type* __s1, const char_type* __s2, size_t __n)
00144       {
00145     std::copy(__s2, __s2 + __n, __s1);
00146     return __s1;
00147       }
00148 
00149       static char_type*
00150       assign(char_type* __s, size_t __n, char_type __a)
00151       {
00152     std::fill_n(__s, __n, __a);
00153         return __s;
00154       }
00155 
00156       static char_type
00157       to_char_type(const int_type& __i)
00158       { return char_type::template from(__i); }
00159 
00160       static int_type
00161       to_int_type(const char_type& __c)
00162       { return char_type::template to<int_type>(__c); }
00163 
00164       static bool
00165       eq_int_type(const int_type& __c1, const int_type& __c2)
00166       { return __c1 == __c2; }
00167 
00168       static int_type
00169       eof() 
00170       {
00171     int_type __r = { -1 };
00172     return __r;
00173       }
00174 
00175       static int_type
00176       not_eof(const int_type& __c)
00177       { return eq_int_type(__c, eof()) ? int_type() : __c; }
00178     };
00179 
00180 _GLIBCXX_END_NAMESPACE
00181 
00182 #endif

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