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
24// file, or you compile this file and link it with other files to
25// produce an executable, this file does not by itself cause the
26// resulting executable to be covered by the GNU General Public
27// License.  This exception does not however invalidate any other
28// reasons why the executable file might be covered by the GNU General
29// Public License.
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
35// notice appears in all copies, and that both that copyright notice
36// and this permission notice appear in supporting documentation. None
37// of the above authors, nor IBM Haifa Research Laboratories, make any
38// representation about the suitability of this software for any
39// purpose. It is provided "as is" without express or implied
40// warranty.
41
42/**
43 * @file ranged_hash_fn.hpp
44 * Contains a unified ranged hash functor, allowing the hash tables
45 * to deal with a single class for ranged hashing.
46 */
47
48#ifndef PB_DS_RANGED_HASH_FN_HPP
49#define PB_DS_RANGED_HASH_FN_HPP
50
51#include <ext/pb_ds/detail/basic_types.hpp>
52#include <utility>
53#include <debug/debug.h>
54
55namespace pb_ds
56{
57  namespace detail
58  {
59    template<typename Key, typename Hash_Fn, typename Allocator,
60	     typename Comb_Hash_Fn, bool Store_Hash>
61    class ranged_hash_fn;
62
63#define PB_DS_CLASS_T_DEC \
64    template<typename Key, typename Hash_Fn, typename Allocator, \
65	     typename Comb_Hash_Fn>
66
67#define PB_DS_CLASS_C_DEC \
68    ranged_hash_fn<Key,	Hash_Fn, Allocator, Comb_Hash_Fn, false>
69
70    /**
71     * Specialization 1
72     * The client supplies a hash function and a ranged hash function,
73     * and requests that hash values not be stored.
74     **/
75    template<typename Key, typename Hash_Fn, typename Allocator,
76	     typename Comb_Hash_Fn>
77    class ranged_hash_fn< Key, Hash_Fn, Allocator, Comb_Hash_Fn, false>
78    : public Hash_Fn, public Comb_Hash_Fn
79    {
80    protected:
81      typedef typename Allocator::size_type size_type;
82      typedef Hash_Fn hash_fn_base;
83      typedef Comb_Hash_Fn comb_hash_fn_base;
84      typedef typename Allocator::template rebind< Key>::other key_allocator;
85      typedef typename key_allocator::const_reference const_key_reference;
86
87      ranged_hash_fn(size_type);
88
89      ranged_hash_fn(size_type, const Hash_Fn&);
90
91      ranged_hash_fn(size_type, const Hash_Fn&, const Comb_Hash_Fn&);
92
93      void
94      swap(PB_DS_CLASS_C_DEC&);
95
96      void
97      notify_resized(size_type);
98
99      inline size_type
100      operator()(const_key_reference) const;
101    };
102
103    PB_DS_CLASS_T_DEC
104    PB_DS_CLASS_C_DEC::
105    ranged_hash_fn(size_type size)
106    { Comb_Hash_Fn::notify_resized(size); }
107
108    PB_DS_CLASS_T_DEC
109    PB_DS_CLASS_C_DEC::
110    ranged_hash_fn(size_type size, const Hash_Fn& r_hash_fn)
111    : Hash_Fn(r_hash_fn)
112    { Comb_Hash_Fn::notify_resized(size); }
113
114    PB_DS_CLASS_T_DEC
115    PB_DS_CLASS_C_DEC::
116    ranged_hash_fn(size_type size, const Hash_Fn& r_hash_fn,
117		   const Comb_Hash_Fn& r_comb_hash_fn)
118    : Hash_Fn(r_hash_fn), Comb_Hash_Fn(r_comb_hash_fn)
119    { comb_hash_fn_base::notify_resized(size); }
120
121    PB_DS_CLASS_T_DEC
122    void
123    PB_DS_CLASS_C_DEC::
124    swap(PB_DS_CLASS_C_DEC& other)
125    {
126      comb_hash_fn_base::swap(other);
127      std::swap((Hash_Fn& )(*this), (Hash_Fn& )other);
128    }
129
130    PB_DS_CLASS_T_DEC
131    void
132    PB_DS_CLASS_C_DEC::
133    notify_resized(size_type size)
134    { comb_hash_fn_base::notify_resized(size); }
135
136    PB_DS_CLASS_T_DEC
137    inline typename PB_DS_CLASS_C_DEC::size_type
138    PB_DS_CLASS_C_DEC::
139    operator()(const_key_reference r_key) const
140    { return (comb_hash_fn_base::operator()(hash_fn_base::operator()(r_key)));}
141
142#undef PB_DS_CLASS_T_DEC
143#undef PB_DS_CLASS_C_DEC
144
145#define PB_DS_CLASS_T_DEC \
146    template<typename Key, typename Hash_Fn, typename Allocator, \
147	     typename Comb_Hash_Fn>
148
149#define PB_DS_CLASS_C_DEC \
150    ranged_hash_fn<Key,Hash_Fn,	Allocator, Comb_Hash_Fn, true>
151
152    /**
153     * Specialization 2
154     * The client supplies a hash function and a ranged hash function,
155     * and requests that hash values be stored.
156     **/
157    template<typename Key, typename Hash_Fn, typename Allocator,
158	     typename Comb_Hash_Fn>
159    class ranged_hash_fn<Key, Hash_Fn, Allocator, Comb_Hash_Fn, true>
160    : public Hash_Fn, public Comb_Hash_Fn
161    {
162    protected:
163      typedef typename Allocator::size_type size_type;
164      typedef std::pair<size_type, size_type> comp_hash;
165      typedef Hash_Fn hash_fn_base;
166      typedef Comb_Hash_Fn comb_hash_fn_base;
167      typedef typename Allocator::template rebind<Key>::other key_allocator;
168      typedef typename key_allocator::const_reference const_key_reference;
169
170      ranged_hash_fn(size_type);
171
172      ranged_hash_fn(size_type, const Hash_Fn&);
173
174      ranged_hash_fn(size_type, const Hash_Fn&, const Comb_Hash_Fn&);
175
176      void
177      swap(PB_DS_CLASS_C_DEC&);
178
179      void
180      notify_resized(size_type);
181
182      inline comp_hash
183      operator()(const_key_reference) const;
184
185      inline comp_hash
186      operator()(const_key_reference, size_type) const;
187    };
188
189    PB_DS_CLASS_T_DEC
190    PB_DS_CLASS_C_DEC::
191    ranged_hash_fn(size_type size)
192    { Comb_Hash_Fn::notify_resized(size); }
193
194    PB_DS_CLASS_T_DEC
195    PB_DS_CLASS_C_DEC::
196    ranged_hash_fn(size_type size, const Hash_Fn& r_hash_fn) :
197      Hash_Fn(r_hash_fn)
198    { Comb_Hash_Fn::notify_resized(size); }
199
200    PB_DS_CLASS_T_DEC
201    PB_DS_CLASS_C_DEC::
202    ranged_hash_fn(size_type size, const Hash_Fn& r_hash_fn,
203		   const Comb_Hash_Fn& r_comb_hash_fn)
204    : Hash_Fn(r_hash_fn), Comb_Hash_Fn(r_comb_hash_fn)
205    { comb_hash_fn_base::notify_resized(size); }
206
207    PB_DS_CLASS_T_DEC
208    void
209    PB_DS_CLASS_C_DEC::
210    swap(PB_DS_CLASS_C_DEC& other)
211    {
212      comb_hash_fn_base::swap(other);
213      std::swap((Hash_Fn& )(*this), (Hash_Fn& )other);
214    }
215
216    PB_DS_CLASS_T_DEC
217    void
218    PB_DS_CLASS_C_DEC::
219    notify_resized(size_type size)
220    { comb_hash_fn_base::notify_resized(size); }
221
222    PB_DS_CLASS_T_DEC
223    inline typename PB_DS_CLASS_C_DEC::comp_hash
224    PB_DS_CLASS_C_DEC::
225    operator()(const_key_reference r_key) const
226    {
227      const size_type hash = hash_fn_base::operator()(r_key);
228      return std::make_pair(comb_hash_fn_base::operator()(hash), hash);
229    }
230
231    PB_DS_CLASS_T_DEC
232    inline typename PB_DS_CLASS_C_DEC::comp_hash
233    PB_DS_CLASS_C_DEC::
234    operator()
235#ifdef _GLIBCXX_DEBUG
236      (const_key_reference r_key, size_type hash) const
237#else
238      (const_key_reference /*r_key*/, size_type hash) const
239#endif
240    {
241      _GLIBCXX_DEBUG_ASSERT(hash == hash_fn_base::operator()(r_key));
242      return std::make_pair(comb_hash_fn_base::operator()(hash), hash);
243    }
244
245#undef PB_DS_CLASS_T_DEC
246#undef PB_DS_CLASS_C_DEC
247
248#define PB_DS_CLASS_T_DEC \
249    template<typename Key, typename Allocator, typename Comb_Hash_Fn>
250
251#define PB_DS_CLASS_C_DEC \
252    ranged_hash_fn<Key,	null_hash_fn, Allocator, Comb_Hash_Fn, false>
253
254    /**
255     * Specialization 3
256     * The client does not supply a hash function (by specifying
257     * null_hash_fn as the Hash_Fn parameter), and requests that hash
258     * values not be stored.
259     **/
260    template<typename Key, typename Allocator, typename Comb_Hash_Fn>
261    class ranged_hash_fn<Key, null_hash_fn, Allocator, Comb_Hash_Fn, false>
262    : public null_hash_fn, public Comb_Hash_Fn
263    {
264    protected:
265      typedef typename Allocator::size_type size_type;
266      typedef Comb_Hash_Fn comb_hash_fn_base;
267
268      ranged_hash_fn(size_type);
269
270      ranged_hash_fn(size_type, const Comb_Hash_Fn&);
271
272      ranged_hash_fn(size_type, const null_hash_fn&, const Comb_Hash_Fn&);
273
274      void
275      swap(PB_DS_CLASS_C_DEC&);
276    };
277
278    PB_DS_CLASS_T_DEC
279    PB_DS_CLASS_C_DEC::
280    ranged_hash_fn(size_type size)
281    { Comb_Hash_Fn::notify_resized(size); }
282
283    PB_DS_CLASS_T_DEC
284    PB_DS_CLASS_C_DEC::
285    ranged_hash_fn(size_type size, const Comb_Hash_Fn& r_comb_hash_fn) :
286      Comb_Hash_Fn(r_comb_hash_fn)
287    { }
288
289    PB_DS_CLASS_T_DEC
290    PB_DS_CLASS_C_DEC::
291    ranged_hash_fn(size_type size, const null_hash_fn& r_null_hash_fn,
292		   const Comb_Hash_Fn& r_comb_hash_fn)
293    : Comb_Hash_Fn(r_comb_hash_fn)
294    { }
295
296    PB_DS_CLASS_T_DEC
297    void
298    PB_DS_CLASS_C_DEC::
299    swap(PB_DS_CLASS_C_DEC& other)
300    { comb_hash_fn_base::swap(other); }
301
302#undef PB_DS_CLASS_T_DEC
303#undef PB_DS_CLASS_C_DEC
304
305#define PB_DS_CLASS_T_DEC \
306    template<typename Key, typename Allocator, typename Comb_Hash_Fn>
307
308#define PB_DS_CLASS_C_DEC \
309    ranged_hash_fn<Key,	null_hash_fn, Allocator, Comb_Hash_Fn, true>
310
311    /**
312     * Specialization 4
313     * The client does not supply a hash function (by specifying
314     * null_hash_fn as the Hash_Fn parameter), and requests that hash
315     * values be stored.
316     **/
317    template<typename Key, typename Allocator, typename Comb_Hash_Fn>
318    class ranged_hash_fn<Key, null_hash_fn, Allocator, Comb_Hash_Fn, true>
319    : public null_hash_fn, public Comb_Hash_Fn
320    {
321    protected:
322      typedef typename Allocator::size_type size_type;
323      typedef Comb_Hash_Fn comb_hash_fn_base;
324
325      ranged_hash_fn(size_type);
326
327      ranged_hash_fn(size_type, const Comb_Hash_Fn&);
328
329      ranged_hash_fn(size_type, const null_hash_fn&, const Comb_Hash_Fn&);
330
331      void
332      swap(PB_DS_CLASS_C_DEC&);
333    };
334
335    PB_DS_CLASS_T_DEC
336    PB_DS_CLASS_C_DEC::
337    ranged_hash_fn(size_type size)
338    { Comb_Hash_Fn::notify_resized(size); }
339
340    PB_DS_CLASS_T_DEC
341    PB_DS_CLASS_C_DEC::
342    ranged_hash_fn(size_type size, const Comb_Hash_Fn& r_comb_hash_fn)
343    : Comb_Hash_Fn(r_comb_hash_fn)
344    { }
345
346    PB_DS_CLASS_T_DEC
347    PB_DS_CLASS_C_DEC::
348    ranged_hash_fn(size_type size, const null_hash_fn& r_null_hash_fn,
349		   const Comb_Hash_Fn& r_comb_hash_fn)
350    : Comb_Hash_Fn(r_comb_hash_fn)
351    { }
352
353    PB_DS_CLASS_T_DEC
354    void
355    PB_DS_CLASS_C_DEC::
356    swap(PB_DS_CLASS_C_DEC& other)
357    { comb_hash_fn_base::swap(other); }
358
359#undef PB_DS_CLASS_T_DEC
360#undef PB_DS_CLASS_C_DEC
361
362  } // namespace detail
363} // namespace pb_ds
364
365#endif
366