1// 'struct hash' from SGI -*- C++ -*-
2
3// Copyright (C) 2001, 2002 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 2, 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// You should have received a copy of the GNU General Public License along
17// with this library; see the file COPYING.  If not, write to the Free
18// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
19// USA.
20
21// As a special exception, you may use this file as part of a free software
22// library without restriction.  Specifically, if other files instantiate
23// templates or use macros or inline functions from this file, or you compile
24// this file and link it with other files to produce an executable, this
25// file does not by itself cause the resulting executable to be covered by
26// the GNU General Public License.  This exception does not however
27// invalidate any other reasons why the executable file might be covered by
28// the GNU General Public License.
29
30/*
31 * Copyright (c) 1996-1998
32 * Silicon Graphics Computer Systems, Inc.
33 *
34 * Permission to use, copy, modify, distribute and sell this software
35 * and its documentation for any purpose is hereby granted without fee,
36 * provided that the above copyright notice appear in all copies and
37 * that both that copyright notice and this permission notice appear
38 * in supporting documentation.  Silicon Graphics makes no
39 * representations about the suitability of this software for any
40 * purpose.  It is provided "as is" without express or implied warranty.
41 *
42 *
43 * Copyright (c) 1994
44 * Hewlett-Packard Company
45 *
46 * Permission to use, copy, modify, distribute and sell this software
47 * and its documentation for any purpose is hereby granted without fee,
48 * provided that the above copyright notice appear in all copies and
49 * that both that copyright notice and this permission notice appear
50 * in supporting documentation.  Hewlett-Packard Company makes no
51 * representations about the suitability of this software for any
52 * purpose.  It is provided "as is" without express or implied warranty.
53 *
54 */
55
56/** @file ext/stl_hash_fun.h
57 *  This file is a GNU extension to the Standard C++ Library (possibly
58 *  containing extensions from the HP/SGI STL subset).  You should only
59 *  include this header if you are using GCC 3 or later.
60 */
61
62#ifndef _CPP_BITS_STL_HASH_FUN_H
63#define _CPP_BITS_STL_HASH_FUN_H 1
64
65#include <cstddef>
66
67namespace __gnu_cxx
68{
69using std::size_t;
70
71template <class _Key> struct hash { };
72
73inline size_t __stl_hash_string(const char* __s)
74{
75  unsigned long __h = 0;
76  for ( ; *__s; ++__s)
77    __h = 5*__h + *__s;
78
79  return size_t(__h);
80}
81
82template<> struct hash<char*>
83{
84  size_t operator()(const char* __s) const { return __stl_hash_string(__s); }
85};
86
87template<> struct hash<const char*>
88{
89  size_t operator()(const char* __s) const { return __stl_hash_string(__s); }
90};
91
92template<> struct hash<char> {
93  size_t operator()(char __x) const { return __x; }
94};
95template<> struct hash<unsigned char> {
96  size_t operator()(unsigned char __x) const { return __x; }
97};
98template<> struct hash<signed char> {
99  size_t operator()(unsigned char __x) const { return __x; }
100};
101template<> struct hash<short> {
102  size_t operator()(short __x) const { return __x; }
103};
104template<> struct hash<unsigned short> {
105  size_t operator()(unsigned short __x) const { return __x; }
106};
107template<> struct hash<int> {
108  size_t operator()(int __x) const { return __x; }
109};
110template<> struct hash<unsigned int> {
111  size_t operator()(unsigned int __x) const { return __x; }
112};
113template<> struct hash<long> {
114  size_t operator()(long __x) const { return __x; }
115};
116template<> struct hash<unsigned long> {
117  size_t operator()(unsigned long __x) const { return __x; }
118};
119
120} // namespace __gnu_cxx
121
122#endif /* _CPP_BITS_STL_HASH_FUN_H */
123
124// Local Variables:
125// mode:C++
126// End:
127