1 // 'struct hash' from SGI -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 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 * Copyright (c) 1996-1998 28 * Silicon Graphics Computer Systems, Inc. 29 * 30 * Permission to use, copy, modify, distribute and sell this software 31 * and its documentation for any purpose is hereby granted without fee, 32 * provided that the above copyright notice appear in all copies and 33 * that both that copyright notice and this permission notice appear 34 * in supporting documentation. Silicon Graphics makes no 35 * representations about the suitability of this software for any 36 * purpose. It is provided "as is" without express or implied warranty. 37 * 38 * 39 * Copyright (c) 1994 40 * Hewlett-Packard Company 41 * 42 * Permission to use, copy, modify, distribute and sell this software 43 * and its documentation for any purpose is hereby granted without fee, 44 * provided that the above copyright notice appear in all copies and 45 * that both that copyright notice and this permission notice appear 46 * in supporting documentation. Hewlett-Packard Company makes no 47 * representations about the suitability of this software for any 48 * purpose. It is provided "as is" without express or implied warranty. 49 * 50 */ 51 52 /** @file backward/hash_fun.h 53 * This file is a GNU extension to the Standard C++ Library (possibly 54 * containing extensions from the HP/SGI STL subset). 55 */ 56 57 #ifndef _BACKWARD_HASH_FUN_H 58 #define _BACKWARD_HASH_FUN_H 1 59 60 #include <bits/c++config.h> 61 62 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) 63 { 64 _GLIBCXX_BEGIN_NAMESPACE_VERSION 65 66 using std::size_t; 67 68 template<class _Key> 69 struct hash { }; 70 71 inline size_t 72 __stl_hash_string(const char* __s) 73 { 74 unsigned long __h = 0; 75 for ( ; *__s; ++__s) 76 __h = 5 * __h + *__s; 77 return size_t(__h); 78 } 79 80 template<> 81 struct hash<char*> 82 { 83 size_t 84 operator()(const char* __s) const 85 { return __stl_hash_string(__s); } 86 }; 87 88 template<> 89 struct hash<const char*> 90 { 91 size_t 92 operator()(const char* __s) const 93 { return __stl_hash_string(__s); } 94 }; 95 96 template<> 97 struct hash<char> 98 { 99 size_t 100 operator()(char __x) const 101 { return __x; } 102 }; 103 104 template<> 105 struct hash<unsigned char> 106 { 107 size_t 108 operator()(unsigned char __x) const 109 { return __x; } 110 }; 111 112 template<> 113 struct hash<signed char> 114 { 115 size_t 116 operator()(unsigned char __x) const 117 { return __x; } 118 }; 119 120 template<> 121 struct hash<short> 122 { 123 size_t 124 operator()(short __x) const 125 { return __x; } 126 }; 127 128 template<> 129 struct hash<unsigned short> 130 { 131 size_t 132 operator()(unsigned short __x) const 133 { return __x; } 134 }; 135 136 template<> 137 struct hash<int> 138 { 139 size_t 140 operator()(int __x) const 141 { return __x; } 142 }; 143 144 template<> 145 struct hash<unsigned int> 146 { 147 size_t 148 operator()(unsigned int __x) const 149 { return __x; } 150 }; 151 152 template<> 153 struct hash<long> 154 { 155 size_t 156 operator()(long __x) const 157 { return __x; } 158 }; 159 160 template<> 161 struct hash<unsigned long> 162 { 163 size_t 164 operator()(unsigned long __x) const 165 { return __x; } 166 }; 167 168 _GLIBCXX_END_NAMESPACE_VERSION 169 } // namespace 170 171 #endif 172
