xref: /openbsd-src/gnu/gcc/libstdc++-v3/include/ext/pb_ds/detail/eq_fn/hash_eq_fn.hpp (revision 404b540a9034ac75a6199ad1a32d1bbc7a0d4210)
1 // -*- C++ -*-
2 
3 // Copyright (C) 2005, 2006 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 terms
7 // of the GNU General Public License as published by the Free Software
8 // Foundation; either version 2, or (at your option) any later
9 // version.
10 
11 // This library is distributed in the hope that it will be useful, but
12 // WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 // General Public License for more details.
15 
16 // You should have received a copy of the GNU General Public License
17 // along with this library; see the file COPYING.  If not, write to
18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
19 // MA 02111-1307, USA.
20 
21 // As a special exception, you may use this file as part of a free
22 // software library without restriction.  Specifically, if other files
23 // instantiate templates or use macros or inline functions from this
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26 // resulting executable to be covered by the GNU General Public
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30 
31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
32 
33 // Permission to use, copy, modify, sell, and distribute this software
34 // is hereby granted without fee, provided that the above copyright
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40 // warranty.
41 
42 /**
43  * @file hash_eq_fn.hpp
44  * Contains 2 eqivalence functions, one employing a hash value,
45  *    and one ignoring it.
46  */
47 
48 #ifndef PB_DS_HASH_EQ_FN_HPP
49 #define PB_DS_HASH_EQ_FN_HPP
50 
51 #include <utility>
52 #include <debug/debug.h>
53 
54 namespace pb_ds
55 {
56   namespace detail
57   {
58     template<typename Key, class Eq_Fn, class Allocator, bool Store_Hash>
59     struct hash_eq_fn;
60 
61 #define PB_DS_CLASS_T_DEC \
62     template<typename Key, class Eq_Fn, class Allocator>
63 
64 #define PB_DS_CLASS_C_DEC \
65     hash_eq_fn<Key, Eq_Fn, Allocator, false>
66 
67     /**
68      * Specialization 1- The client requests that hash values not be stored.
69      **/
70     template<typename Key, class Eq_Fn, class Allocator>
71     struct hash_eq_fn<Key, Eq_Fn, Allocator, false> : public Eq_Fn
72     {
73       typedef Eq_Fn eq_fn_base;
74 
75       typedef typename Allocator::template rebind<Key>::other key_allocator;
76 
77       typedef typename key_allocator::const_reference const_key_reference;
78 
79       hash_eq_fn();
80 
81       hash_eq_fn(const Eq_Fn& r_eq_fn);
82 
83       inline bool
84       operator()(const_key_reference r_lhs_key, const_key_reference r_rhs_key) const;
85 
86       inline void
87       swap(const PB_DS_CLASS_C_DEC& other);
88     };
89 
90     PB_DS_CLASS_T_DEC
91     PB_DS_CLASS_C_DEC::
hash_eq_fn()92     hash_eq_fn()
93     { }
94 
95     PB_DS_CLASS_T_DEC
96     inline void
97     PB_DS_CLASS_C_DEC::
swap(const PB_DS_CLASS_C_DEC & other)98     swap(const PB_DS_CLASS_C_DEC& other)
99     { std::swap((Eq_Fn& )(*this), (Eq_Fn& )other); }
100 
101     PB_DS_CLASS_T_DEC
102     PB_DS_CLASS_C_DEC::
hash_eq_fn(const Eq_Fn & r_eq_fn)103     hash_eq_fn(const Eq_Fn& r_eq_fn) :
104       Eq_Fn(r_eq_fn)
105     { }
106 
107     PB_DS_CLASS_T_DEC
108     inline bool
109     PB_DS_CLASS_C_DEC::
operator ()(const_key_reference r_lhs_key,const_key_reference r_rhs_key) const110     operator()(const_key_reference r_lhs_key, const_key_reference r_rhs_key) const
111     { return (eq_fn_base::operator()(r_lhs_key, r_rhs_key)); }
112 
113 #undef PB_DS_CLASS_T_DEC
114 #undef PB_DS_CLASS_C_DEC
115 
116 #define PB_DS_CLASS_T_DEC \
117     template<typename Key, class Eq_Fn, class Allocator>
118 
119 #define PB_DS_CLASS_C_DEC \
120     hash_eq_fn<Key, Eq_Fn, Allocator, true>
121 
122     /**
123      * Specialization 2- The client requests that hash values be stored.
124      **/
125     template<typename Key, class Eq_Fn, class Allocator>
126     struct hash_eq_fn<Key, Eq_Fn, Allocator, true> :
127       public Eq_Fn
128     {
129       typedef typename Allocator::size_type size_type;
130 
131       typedef Eq_Fn eq_fn_base;
132 
133       typedef typename Allocator::template rebind<Key>::other key_allocator;
134 
135       typedef typename key_allocator::const_reference const_key_reference;
136 
137       hash_eq_fn();
138 
139       hash_eq_fn(const Eq_Fn& r_eq_fn);
140 
141       inline bool
142       operator()(const_key_reference r_lhs_key, size_type lhs_hash,
143 		 const_key_reference r_rhs_key, size_type rhs_hash) const;
144 
145       inline void
146       swap(const PB_DS_CLASS_C_DEC& other);
147     };
148 
149     PB_DS_CLASS_T_DEC
150     PB_DS_CLASS_C_DEC::
hash_eq_fn()151     hash_eq_fn()
152     { }
153 
154     PB_DS_CLASS_T_DEC
155     PB_DS_CLASS_C_DEC::
hash_eq_fn(const Eq_Fn & r_eq_fn)156     hash_eq_fn(const Eq_Fn& r_eq_fn) :
157       Eq_Fn(r_eq_fn)
158     { }
159 
160     PB_DS_CLASS_T_DEC
161     inline bool
162     PB_DS_CLASS_C_DEC::
operator ()(const_key_reference r_lhs_key,size_type lhs_hash,const_key_reference r_rhs_key,size_type rhs_hash) const163     operator()(const_key_reference r_lhs_key, size_type lhs_hash,
164 	       const_key_reference r_rhs_key, size_type rhs_hash) const
165     {
166       _GLIBCXX_DEBUG_ASSERT(!eq_fn_base::operator()(r_lhs_key, r_rhs_key)
167 		            || lhs_hash == rhs_hash);
168 
169       return (lhs_hash == rhs_hash &&
170 	      eq_fn_base::operator()(r_lhs_key, r_rhs_key));
171     }
172 
173     PB_DS_CLASS_T_DEC
174     inline void
175     PB_DS_CLASS_C_DEC::
swap(const PB_DS_CLASS_C_DEC & other)176     swap(const PB_DS_CLASS_C_DEC& other)
177     { std::swap((Eq_Fn& )(*this), (Eq_Fn& )(other)); }
178 
179 #undef PB_DS_CLASS_T_DEC
180 #undef PB_DS_CLASS_C_DEC
181 
182   } // namespace detail
183 } // namespace pb_ds
184 
185 #endif
186