libstdc++-v3/include/ext/pb_ds/detail/hash_fn/ranged_hash_fn.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005, 2006, 2009, 2011 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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
  26
  27 // Permission to use, copy, modify, sell, and distribute this software
  28 // is hereby granted without fee, provided that the above copyright
  29 // notice appears in all copies, and that both that copyright notice
  30 // and this permission notice appear in supporting documentation. None
  31 // of the above authors, nor IBM Haifa Research Laboratories, make any
  32 // representation about the suitability of this software for any
  33 // purpose. It is provided "as is" without express or implied
  34 // warranty.
  35
  36 /**
  37  * @file ranged_hash_fn.hpp
  38  * Contains a unified ranged hash functor, allowing the hash tables
  39  * to deal with a single class for ranged hashing.
  40  */
  41
  42 #ifndef PB_DS_RANGED_HASH_FN_HPP
  43 #define PB_DS_RANGED_HASH_FN_HPP
  44
  45 #include <utility>
  46 #include <debug/debug.h>
  47
  48 namespace __gnu_pbds
  49 {
  50   namespace detail
  51   {
  52     template<typename Key, typename Hash_Fn, typename _Alloc,
  53              typename Comb_Hash_Fn, bool Store_Hash>
  54     class ranged_hash_fn;
  55
  56 #define PB_DS_CLASS_T_DEC \
  57     template<typename Key, typename Hash_Fn, typename _Alloc, \
  58              typename Comb_Hash_Fn>
  59
  60 #define PB_DS_CLASS_C_DEC \
  61     ranged_hash_fn<Key, Hash_Fn, _Alloc, Comb_Hash_Fn, false>
  62
  63     /**
  64      * Specialization 1
  65      * The client supplies a hash function and a ranged hash function,
  66      * and requests that hash values not be stored.
  67      **/
  68     template<typename Key, typename Hash_Fn, typename _Alloc,
  69              typename Comb_Hash_Fn>
  70     class ranged_hash_fn< Key, Hash_Fn, _Alloc, Comb_Hash_Fn, false>
  71     : public Hash_Fn, public Comb_Hash_Fn
  72     {
  73     protected:
  74       typedef typename _Alloc::size_type size_type;
  75       typedef Hash_Fn hash_fn_base;
  76       typedef Comb_Hash_Fn comb_hash_fn_base;
  77       typedef typename _Alloc::template rebind< Key>::other key_allocator;
  78       typedef typename key_allocator::const_reference key_const_reference;
  79
  80       ranged_hash_fn(size_type);
  81
  82       ranged_hash_fn(size_type, const Hash_Fn&);
  83
  84       ranged_hash_fn(size_type, const Hash_Fn&, const Comb_Hash_Fn&);
  85
  86       void
  87       swap(PB_DS_CLASS_C_DEC&);
  88
  89       void
  90       notify_resized(size_type);
  91
  92       inline size_type
  93       operator()(key_const_reference) const;
  94     };
  95
  96     PB_DS_CLASS_T_DEC
  97     PB_DS_CLASS_C_DEC::
  98     ranged_hash_fn(size_type size)
  99     { Comb_Hash_Fn::notify_resized(size); }
 100
 101     PB_DS_CLASS_T_DEC
 102     PB_DS_CLASS_C_DEC::
 103     ranged_hash_fn(size_type size, const Hash_Fn& r_hash_fn)
 104     : Hash_Fn(r_hash_fn)
 105     { Comb_Hash_Fn::notify_resized(size); }
 106
 107     PB_DS_CLASS_T_DEC
 108     PB_DS_CLASS_C_DEC::
 109     ranged_hash_fn(size_type size, const Hash_Fn& r_hash_fn,
 110                    const Comb_Hash_Fn& r_comb_hash_fn)
 111     : Hash_Fn(r_hash_fn), Comb_Hash_Fn(r_comb_hash_fn)
 112     { comb_hash_fn_base::notify_resized(size); }
 113
 114     PB_DS_CLASS_T_DEC
 115     void
 116     PB_DS_CLASS_C_DEC::
 117     swap(PB_DS_CLASS_C_DEC& other)
 118     {
 119       comb_hash_fn_base::swap(other);
 120       std::swap((Hash_Fn& )(*this), (Hash_Fn& )other);
 121     }
 122
 123     PB_DS_CLASS_T_DEC
 124     void
 125     PB_DS_CLASS_C_DEC::
 126     notify_resized(size_type size)
 127     { comb_hash_fn_base::notify_resized(size); }
 128
 129     PB_DS_CLASS_T_DEC
 130     inline typename PB_DS_CLASS_C_DEC::size_type
 131     PB_DS_CLASS_C_DEC::
 132     operator()(key_const_reference r_key) const
 133     { return (comb_hash_fn_base::operator()(hash_fn_base::operator()(r_key)));}
 134
 135 #undef PB_DS_CLASS_T_DEC
 136 #undef PB_DS_CLASS_C_DEC
 137
 138 #define PB_DS_CLASS_T_DEC \
 139     template<typename Key, typename Hash_Fn, typename _Alloc, \
 140              typename Comb_Hash_Fn>
 141
 142 #define PB_DS_CLASS_C_DEC \
 143     ranged_hash_fn<Key,Hash_Fn, _Alloc, Comb_Hash_Fn, true>
 144
 145     /**
 146      * Specialization 2
 147      * The client supplies a hash function and a ranged hash function,
 148      * and requests that hash values be stored.
 149      **/
 150     template<typename Key, typename Hash_Fn, typename _Alloc,
 151              typename Comb_Hash_Fn>
 152     class ranged_hash_fn<Key, Hash_Fn, _Alloc, Comb_Hash_Fn, true>
 153     : public Hash_Fn, public Comb_Hash_Fn
 154     {
 155     protected:
 156       typedef typename _Alloc::size_type size_type;
 157       typedef std::pair<size_type, size_type> comp_hash;
 158       typedef Hash_Fn hash_fn_base;
 159       typedef Comb_Hash_Fn comb_hash_fn_base;
 160       typedef typename _Alloc::template rebind<Key>::other key_allocator;
 161       typedef typename key_allocator::const_reference key_const_reference;
 162
 163       ranged_hash_fn(size_type);
 164
 165       ranged_hash_fn(size_type, const Hash_Fn&);
 166
 167       ranged_hash_fn(size_type, const Hash_Fn&, const Comb_Hash_Fn&);
 168
 169       void
 170       swap(PB_DS_CLASS_C_DEC&);
 171
 172       void
 173       notify_resized(size_type);
 174
 175       inline comp_hash
 176       operator()(key_const_reference) const;
 177
 178       inline comp_hash
 179       operator()(key_const_reference, size_type) const;
 180     };
 181
 182     PB_DS_CLASS_T_DEC
 183     PB_DS_CLASS_C_DEC::
 184     ranged_hash_fn(size_type size)
 185     { Comb_Hash_Fn::notify_resized(size); }
 186
 187     PB_DS_CLASS_T_DEC
 188     PB_DS_CLASS_C_DEC::
 189     ranged_hash_fn(size_type size, const Hash_Fn& r_hash_fn) :
 190       Hash_Fn(r_hash_fn)
 191     { Comb_Hash_Fn::notify_resized(size); }
 192
 193     PB_DS_CLASS_T_DEC
 194     PB_DS_CLASS_C_DEC::
 195     ranged_hash_fn(size_type size, const Hash_Fn& r_hash_fn,
 196                    const Comb_Hash_Fn& r_comb_hash_fn)
 197     : Hash_Fn(r_hash_fn), Comb_Hash_Fn(r_comb_hash_fn)
 198     { comb_hash_fn_base::notify_resized(size); }
 199
 200     PB_DS_CLASS_T_DEC
 201     void
 202     PB_DS_CLASS_C_DEC::
 203     swap(PB_DS_CLASS_C_DEC& other)
 204     {
 205       comb_hash_fn_base::swap(other);
 206       std::swap((Hash_Fn& )(*this), (Hash_Fn& )other);
 207     }
 208
 209     PB_DS_CLASS_T_DEC
 210     void
 211     PB_DS_CLASS_C_DEC::
 212     notify_resized(size_type size)
 213     { comb_hash_fn_base::notify_resized(size); }
 214
 215     PB_DS_CLASS_T_DEC
 216     inline typename PB_DS_CLASS_C_DEC::comp_hash
 217     PB_DS_CLASS_C_DEC::
 218     operator()(key_const_reference r_key) const
 219     {
 220       const size_type hash = hash_fn_base::operator()(r_key);
 221       return std::make_pair(comb_hash_fn_base::operator()(hash), hash);
 222     }
 223
 224     PB_DS_CLASS_T_DEC
 225     inline typename PB_DS_CLASS_C_DEC::comp_hash
 226     PB_DS_CLASS_C_DEC::
 227     operator()
 228 #ifdef _GLIBCXX_DEBUG
 229       (key_const_reference r_key, size_type hash) const
 230 #else
 231       (key_const_reference /*r_key*/, size_type hash) const
 232 #endif
 233     {
 234       _GLIBCXX_DEBUG_ASSERT(hash == hash_fn_base::operator()(r_key));
 235       return std::make_pair(comb_hash_fn_base::operator()(hash), hash);
 236     }
 237
 238 #undef PB_DS_CLASS_T_DEC
 239 #undef PB_DS_CLASS_C_DEC
 240
 241 #define PB_DS_CLASS_T_DEC \
 242     template<typename Key, typename _Alloc, typename Comb_Hash_Fn>
 243
 244 #define PB_DS_CLASS_C_DEC \
 245     ranged_hash_fn<Key, null_type, _Alloc, Comb_Hash_Fn, false>
 246
 247     /**
 248      * Specialization 3
 249      * The client does not supply a hash function (by specifying
 250      * null_type as the Hash_Fn parameter), and requests that hash
 251      * values not be stored.
 252      **/
 253     template<typename Key, typename _Alloc, typename Comb_Hash_Fn>
 254     class ranged_hash_fn<Key, null_type, _Alloc, Comb_Hash_Fn, false>
 255     : public Comb_Hash_Fn
 256     {
 257     protected:
 258       typedef typename _Alloc::size_type size_type;
 259       typedef Comb_Hash_Fn comb_hash_fn_base;
 260
 261       ranged_hash_fn(size_type);
 262
 263       ranged_hash_fn(size_type, const Comb_Hash_Fn&);
 264
 265       ranged_hash_fn(size_type, const null_type&, const Comb_Hash_Fn&);
 266
 267       void
 268       swap(PB_DS_CLASS_C_DEC&);
 269     };
 270
 271     PB_DS_CLASS_T_DEC
 272     PB_DS_CLASS_C_DEC::
 273     ranged_hash_fn(size_type size)
 274     { Comb_Hash_Fn::notify_resized(size); }
 275
 276     PB_DS_CLASS_T_DEC
 277     PB_DS_CLASS_C_DEC::
 278     ranged_hash_fn(size_type size, const Comb_Hash_Fn& r_comb_hash_fn) :
 279       Comb_Hash_Fn(r_comb_hash_fn)
 280     { }
 281
 282     PB_DS_CLASS_T_DEC
 283     PB_DS_CLASS_C_DEC::
 284     ranged_hash_fn(size_type size, const null_type& r_null_type,
 285                    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     void
 291     PB_DS_CLASS_C_DEC::
 292     swap(PB_DS_CLASS_C_DEC& other)
 293     { comb_hash_fn_base::swap(other); }
 294
 295 #undef PB_DS_CLASS_T_DEC
 296 #undef PB_DS_CLASS_C_DEC
 297
 298 #define PB_DS_CLASS_T_DEC \
 299     template<typename Key, typename _Alloc, typename Comb_Hash_Fn>
 300
 301 #define PB_DS_CLASS_C_DEC \
 302     ranged_hash_fn<Key, null_type, _Alloc, Comb_Hash_Fn, true>
 303
 304     /**
 305      * Specialization 4
 306      * The client does not supply a hash function (by specifying
 307      * null_type as the Hash_Fn parameter), and requests that hash
 308      * values be stored.
 309      **/
 310     template<typename Key, typename _Alloc, typename Comb_Hash_Fn>
 311     class ranged_hash_fn<Key, null_type, _Alloc, Comb_Hash_Fn, true>
 312     : public Comb_Hash_Fn
 313     {
 314     protected:
 315       typedef typename _Alloc::size_type size_type;
 316       typedef Comb_Hash_Fn comb_hash_fn_base;
 317
 318       ranged_hash_fn(size_type);
 319
 320       ranged_hash_fn(size_type, const Comb_Hash_Fn&);
 321
 322       ranged_hash_fn(size_type, const null_type&, const Comb_Hash_Fn&);
 323
 324       void
 325       swap(PB_DS_CLASS_C_DEC&);
 326     };
 327
 328     PB_DS_CLASS_T_DEC
 329     PB_DS_CLASS_C_DEC::
 330     ranged_hash_fn(size_type size)
 331     { Comb_Hash_Fn::notify_resized(size); }
 332
 333     PB_DS_CLASS_T_DEC
 334     PB_DS_CLASS_C_DEC::
 335     ranged_hash_fn(size_type size, const Comb_Hash_Fn& r_comb_hash_fn)
 336     : Comb_Hash_Fn(r_comb_hash_fn)
 337     { }
 338
 339     PB_DS_CLASS_T_DEC
 340     PB_DS_CLASS_C_DEC::
 341     ranged_hash_fn(size_type size, const null_type& r_null_type,
 342                    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     void
 348     PB_DS_CLASS_C_DEC::
 349     swap(PB_DS_CLASS_C_DEC& other)
 350     { comb_hash_fn_base::swap(other); }
 351
 352 #undef PB_DS_CLASS_T_DEC
 353 #undef PB_DS_CLASS_C_DEC
 354
 355   } // namespace detail
 356 } // namespace __gnu_pbds
 357
 358 #endif