# char_traits.h

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    00001 // Character Traits for use by standard string and iostream -*- C++ -*-
    00002
    00003 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002
    00004 // Free Software Foundation, Inc.
    00005 //
    00006 // This file is part of the GNU ISO C++ Library.  This library is free
    00007 // software; you can redistribute it and/or modify it under the
    00008 // terms of the GNU General Public License as published by the
    00009 // Free Software Foundation; either version 2, or (at your option)
    00010 // any later version.
    00011
    00012 // This library is distributed in the hope that it will be useful,
    00013 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00015 // GNU General Public License for more details.
    00016
    00017 // You should have received a copy of the GNU General Public License along
    00018 // with this library; see the file COPYING.  If not, write to the Free
    00019 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
    00020 // USA.
    00021
    00022 // As a special exception, you may use this file as part of a free software
    00023 // library without restriction.  Specifically, if other files instantiate
    00024 // templates or use macros or inline functions from this file, or you compile
    00025 // this file and link it with other files to produce an executable, this
    00026 // file does not by itself cause the resulting executable to be covered by
    00027 // the GNU General Public License.  This exception does not however
    00028 // invalidate any other reasons why the executable file might be covered by
    00029 // the GNU General Public License.
    00030
    00031 //
    00032 // ISO C++ 14882: 21  Strings library
    00033 //
    00034
    00040 #ifndef _CPP_BITS_CHAR_TRAITS_H
    00041 #define _CPP_BITS_CHAR_TRAITS_H 1
    00042
    00043 #pragma GCC system_header
    00044
    00045 #include <cstring>            // For memmove, memset, memchr
    00046 #include <bits/fpos.h>        // For streampos
    00047
    00048 namespace std
    00049 {
    00050   // 21.1
    00061   template<class _CharT>
    00062     struct char_traits
    00063     {
    00064       typedef _CharT        char_type;
    00065       // Unsigned as wint_t is unsigned.
    00066       typedef unsigned long     int_type;
    00067       typedef streampos     pos_type;
    00068       typedef streamoff     off_type;
    00069       typedef mbstate_t     state_type;
    00070
    00071       static void
    00072       assign(char_type& __c1, const char_type& __c2);
    00073
    00074       static bool
    00075       eq(const char_type& __c1, const char_type& __c2);
    00076
    00077       static bool
    00078       lt(const char_type& __c1, const char_type& __c2);
    00079
    00080       static int
    00081       compare(const char_type* __s1, const char_type* __s2, size_t __n);
    00082
    00083       static size_t
    00084       length(const char_type* __s);
    00085
    00086       static const char_type*
    00087       find(const char_type* __s, size_t __n, const char_type& __a);
    00088
    00089       static char_type*
    00090       move(char_type* __s1, const char_type* __s2, size_t __n);
    00091
    00092       static char_type*
    00093       copy(char_type* __s1, const char_type* __s2, size_t __n);
    00094
    00095       static char_type*
    00096       assign(char_type* __s, size_t __n, char_type __a);
    00097
    00098       static char_type
    00099       to_char_type(const int_type& __c);
    00100
    00101       static int_type
    00102       to_int_type(const char_type& __c);
    00103
    00104       static bool
    00105       eq_int_type(const int_type& __c1, const int_type& __c2);
    00106
    00107       static int_type
    00108       eof();
    00109
    00110       static int_type
    00111       not_eof(const int_type& __c);
    00112     };
    00113
    00114
    00116   template<>
    00117     struct char_traits<char>
    00118     {
    00119       typedef char      char_type;
    00120       typedef int           int_type;
    00121       typedef streampos     pos_type;
    00122       typedef streamoff     off_type;
    00123       typedef mbstate_t     state_type;
    00124
    00125       static void
    00126       assign(char_type& __c1, const char_type& __c2)
    00127       { __c1 = __c2; }
    00128
    00129       static bool
    00130       eq(const char_type& __c1, const char_type& __c2)
    00131       { return __c1 == __c2; }
    00132
    00133       static bool
    00134       lt(const char_type& __c1, const char_type& __c2)
    00135       { return __c1 < __c2; }
    00136
    00137       static int
    00138       compare(const char_type* __s1, const char_type* __s2, size_t __n)
    00139       { return memcmp(__s1, __s2, __n); }
    00140
    00141       static size_t
    00142       length(const char_type* __s)
    00143       { return strlen(__s); }
    00144
    00145       static const char_type*
    00146       find(const char_type* __s, size_t __n, const char_type& __a)
    00147       { return static_cast<const char_type*>(memchr(__s, __a, __n)); }
    00148
    00149       static char_type*
    00150       move(char_type* __s1, const char_type* __s2, size_t __n)
    00151       { return static_cast<char_type*>(memmove(__s1, __s2, __n)); }
    00152
    00153       static char_type*
    00154       copy(char_type* __s1, const char_type* __s2, size_t __n)
    00155       {  return static_cast<char_type*>(memcpy(__s1, __s2, __n)); }
    00156
    00157       static char_type*
    00158       assign(char_type* __s, size_t __n, char_type __a)
    00159       { return static_cast<char_type*>(memset(__s, __a, __n)); }
    00160
    00161       static char_type
    00162       to_char_type(const int_type& __c)
    00163       { return static_cast<char_type>(__c); }
    00164
    00165       // To keep both the byte 0xff and the eof symbol 0xffffffff
    00166       // from ending up as 0xffffffff.
    00167       static int_type
    00168       to_int_type(const char_type& __c)
    00169       { return static_cast<int_type>(static_cast<unsigned char>(__c)); }
    00170
    00171       static bool
    00172       eq_int_type(const int_type& __c1, const int_type& __c2)
    00173       { return __c1 == __c2; }
    00174
    00175       static int_type
    00176       eof() { return static_cast<int_type>(EOF); }
    00177
    00178       static int_type
    00179       not_eof(const int_type& __c)
    00180       { return (__c == eof()) ? 0 : __c; }
    00181   };
    00182
    00183
    00184 #ifdef _GLIBCPP_USE_WCHAR_T
    00185
    00186   template<>
    00187     struct char_traits<wchar_t>
    00188     {
    00189       typedef wchar_t       char_type;
    00190       typedef wint_t        int_type;
    00191       typedef streamoff     off_type;
    00192       typedef wstreampos    pos_type;
    00193       typedef mbstate_t     state_type;
    00194
    00195       static void
    00196       assign(char_type& __c1, const char_type& __c2)
    00197       { __c1 = __c2; }
    00198
    00199       static bool
    00200       eq(const char_type& __c1, const char_type& __c2)
    00201       { return __c1 == __c2; }
    00202
    00203       static bool
    00204       lt(const char_type& __c1, const char_type& __c2)
    00205       { return __c1 < __c2; }
    00206
    00207       static int
    00208       compare(const char_type* __s1, const char_type* __s2, size_t __n)
    00209       { return wmemcmp(__s1, __s2, __n); }
    00210
    00211       static size_t
    00212       length(const char_type* __s)
    00213       { return wcslen(__s); }
    00214
    00215       static const char_type*
    00216       find(const char_type* __s, size_t __n, const char_type& __a)
    00217       { return wmemchr(__s, __a, __n); }
    00218
    00219       static char_type*
    00220       move(char_type* __s1, const char_type* __s2, int_type __n)
    00221       { return wmemmove(__s1, __s2, __n); }
    00222
    00223       static char_type*
    00224       copy(char_type* __s1, const char_type* __s2, size_t __n)
    00225       { return wmemcpy(__s1, __s2, __n); }
    00226
    00227       static char_type*
    00228       assign(char_type* __s, size_t __n, char_type __a)
    00229       { return wmemset(__s, __a, __n); }
    00230
    00231       static char_type
    00232       to_char_type(const int_type& __c) { return char_type(__c); }
    00233
    00234       static int_type
    00235       to_int_type(const char_type& __c) { return int_type(__c); }
    00236
    00237       static bool
    00238       eq_int_type(const int_type& __c1, const int_type& __c2)
    00239       { return __c1 == __c2; }
    00240
    00241       static int_type
    00242       eof() { return static_cast<int_type>(WEOF); }
    00243
    00244       static int_type
    00245       not_eof(const int_type& __c)
    00246       { return eq_int_type(__c, eof()) ? 0 : __c; }
    00247   };
    00248 #endif //_GLIBCPP_USE_WCHAR_T
    00249
    00250   template<typename _CharT, typename _Traits>
    00251     struct _Char_traits_match
    00252     {
    00253       _CharT _M_c;
    00254       _Char_traits_match(_CharT const& __c) : _M_c(__c) { }
    00255
    00256       bool
    00257       operator()(_CharT const& __a) { return _Traits::eq(_M_c, __a); }
    00258     };
    00259 } // namespace std
    00260
    00261 #endif