xref: /reactos/sdk/include/c++/stlport/stl/_hash_fun.h (revision c2c66aff)
1 /*
2  * Copyright (c) 1996-1998
3  * Silicon Graphics Computer Systems, Inc.
4  *
5  * Permission to use, copy, modify, distribute and sell this software
6  * and its documentation for any purpose is hereby granted without fee,
7  * provided that the above copyright notice appear in all copies and
8  * that both that copyright notice and this permission notice appear
9  * in supporting documentation.  Silicon Graphics makes no
10  * representations about the suitability of this software for any
11  * purpose.  It is provided "as is" without express or implied warranty.
12  *
13  *
14  * Copyright (c) 1994
15  * Hewlett-Packard Company
16  *
17  * Permission to use, copy, modify, distribute and sell this software
18  * and its documentation for any purpose is hereby granted without fee,
19  * provided that the above copyright notice appear in all copies and
20  * that both that copyright notice and this permission notice appear
21  * in supporting documentation.  Hewlett-Packard Company makes no
22  * representations about the suitability of this software for any
23  * purpose.  It is provided "as is" without express or implied warranty.
24  *
25  */
26 
27 /* NOTE: This is an internal header file, included by other STL headers.
28  *   You should not attempt to use it directly.
29  */
30 
31 #ifndef _STLP_HASH_FUN_H
32 #define _STLP_HASH_FUN_H
33 
34 #ifndef _STLP_INTERNAL_CSTDDEF
35 #  include <stl/_cstddef.h>
36 #endif
37 
38 _STLP_BEGIN_NAMESPACE
39 
40 template <class _Key> struct hash { };
41 
42 _STLP_MOVE_TO_PRIV_NAMESPACE
43 
__stl_hash_string(const char * __s)44 inline size_t __stl_hash_string(const char* __s) {
45   _STLP_FIX_LITERAL_BUG(__s)
46   unsigned long __h = 0;
47   for ( ; *__s; ++__s)
48     __h = 5*__h + *__s;
49 
50   return size_t(__h);
51 }
52 
53 _STLP_MOVE_TO_STD_NAMESPACE
54 
55 _STLP_TEMPLATE_NULL
56 struct hash<char*> {
57   size_t operator()(const char* __s) const {
58     _STLP_FIX_LITERAL_BUG(__s)
59     return _STLP_PRIV __stl_hash_string(__s);
60   }
61 };
62 
63 _STLP_TEMPLATE_NULL
64 struct hash<const char*> {
65   size_t operator()(const char* __s) const {
66     _STLP_FIX_LITERAL_BUG(__s)
67     return _STLP_PRIV __stl_hash_string(__s);
68   }
69 };
70 
71 _STLP_TEMPLATE_NULL struct hash<char> {
72   size_t operator()(char __x) const { return __x; }
73 };
74 _STLP_TEMPLATE_NULL struct hash<unsigned char> {
75   size_t operator()(unsigned char __x) const { return __x; }
76 };
77 #if !defined (_STLP_NO_SIGNED_BUILTINS)
78 _STLP_TEMPLATE_NULL struct hash<signed char> {
79   size_t operator()(unsigned char __x) const { return __x; }
80 };
81 #endif
82 _STLP_TEMPLATE_NULL struct hash<short> {
83   size_t operator()(short __x) const { return __x; }
84 };
85 _STLP_TEMPLATE_NULL struct hash<unsigned short> {
86   size_t operator()(unsigned short __x) const { return __x; }
87 };
88 _STLP_TEMPLATE_NULL struct hash<int> {
89   size_t operator()(int __x) const { return __x; }
90 };
91 
92 #if !defined (_STLP_MSVC) || (_STLP_MSVC < 1300) || defined (_WIN64)
93 _STLP_TEMPLATE_NULL struct hash<unsigned int> {
94   size_t operator()(unsigned int __x) const { return __x; }
95 };
96 #else
97 /* MSVC .Net since 2002 has a 64 bits portability warning feature. typedef
98  * like size_t are tagged as potential 64 bits variables making them different from
99  * unsigned int. To avoid the warning when a hash container is instanciated with
100  * the size_t key we prefer to grant the size_t specialization rather than the
101  * unsigned int one.
102  */
103 _STLP_TEMPLATE_NULL struct hash<size_t> {
104   size_t operator()(size_t __x) const { return __x; }
105 };
106 #endif
107 
108 _STLP_TEMPLATE_NULL struct hash<long> {
109   size_t operator()(long __x) const { return __x; }
110 };
111 _STLP_TEMPLATE_NULL struct hash<unsigned long> {
112   size_t operator()(unsigned long __x) const { return __x; }
113 };
114 
115 #if defined (_STLP_LONG_LONG)
116 _STLP_TEMPLATE_NULL struct hash<_STLP_LONG_LONG> {
117   size_t operator()(_STLP_LONG_LONG x) const { return (size_t)x; }
118 };
119 _STLP_TEMPLATE_NULL struct hash<unsigned _STLP_LONG_LONG> {
120   size_t operator()(unsigned _STLP_LONG_LONG x) const { return (size_t)x; }
121 };
122 #endif
123 
124 _STLP_TEMPLATE_NULL
125 struct hash<void *>
126 {
127     union __vp {
128         size_t s;
129         void  *p;
130     };
131 
132     size_t operator()(void *__x) const
133       {
134         __vp vp;
135         vp.p = __x;
136         return vp.s;
137       }
138 };
139 
140 _STLP_END_NAMESPACE
141 
142 #endif /* _STLP_HASH_FUN_H */
143 
144 // Local Variables:
145 // mode:C++
146 // End:
147