1 // std::collate implementation details, generic version -*- C++ -*-
2 
3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010
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 //
27 // ISO C++ 14882: 22.2.4.1.2  collate virtual functions
28 //
29 
30 // Written by Benjamin Kosnik <bkoz@redhat.com>
31 
32 #include <locale>
33 #include <cstring>
34 
35 namespace std _GLIBCXX_VISIBILITY(default)
36 {
37 _GLIBCXX_BEGIN_NAMESPACE_VERSION
38 
39   // These are basically extensions to char_traits, and perhaps should
40   // be put there instead of here.
41   template<>
42     int
43     collate<char>::_M_compare(const char* __one,
44 			      const char* __two) const throw()
45     {
46       int __cmp = strcoll(__one, __two);
47       return (__cmp >> (8 * sizeof (int) - 2)) | (__cmp != 0);
48     }
49 
50   template<>
51     size_t
52     collate<char>::_M_transform(char* __to, const char* __from,
53 				size_t __n) const throw()
54     { return strxfrm(__to, __from, __n); }
55 
56 #ifdef _GLIBCXX_USE_WCHAR_T
57   template<>
58     int
59     collate<wchar_t>::_M_compare(const wchar_t* __one,
60 				 const wchar_t* __two) const throw()
61     {
62       int __cmp = wcscoll(__one, __two);
63       return (__cmp >> (8 * sizeof (int) - 2)) | (__cmp != 0);
64     }
65 
66   template<>
67     size_t
68     collate<wchar_t>::_M_transform(wchar_t* __to, const wchar_t* __from,
69 				   size_t __n) const throw()
70     { return wcsxfrm(__to, __from, __n); }
71 #endif
72 
73 _GLIBCXX_END_NAMESPACE_VERSION
74 } // namespace
75