astar_pphash.h revision 4a68b3365c8c50aa93505e99ead2565ab73dcdb0 
1/*---------------------------------------------------------------------------*
2 *  astar_pphash.h  *
3 *                                                                           *
4 *  Copyright 2007, 2008 Nuance Communciations, Inc.                               *
5 *                                                                           *
6 *  Licensed under the Apache License, Version 2.0 (the 'License');          *
7 *  you may not use this file except in compliance with the License.         *
8 *                                                                           *
9 *  You may obtain a copy of the License at                                  *
10 *      http://www.apache.org/licenses/LICENSE-2.0                           *
11 *                                                                           *
12 *  Unless required by applicable law or agreed to in writing, software      *
13 *  distributed under the License is distributed on an 'AS IS' BASIS,        *
14 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
15 *  See the License for the specific language governing permissions and      *
16 *  limitations under the License.                                           *
17 *                                                                           *
18 *---------------------------------------------------------------------------*/
19
20#ifndef __ASTAR_PPHASH__
21#define __ASTAR_PPHASH__
22
23#define FSH_SUCCESS       0
24#define FSH_KEY_OCCUPIED  1
25#define FSH_NO_SUCH_KEY   2
26#define FSH_HASHSIZE     37
27#define FSH_NULL 0
28
29#include "astar.h"
30
31/**
32 * The FixedSizeHash is a hash that does not grow in size.
33 * In each bin there are a number of elements, which are maintained
34 * via a linked list.
35 * This is used to find out whether a path with the same word history
36 * as the one being expanded has already been search.  If yes, we can
37 * abort this one.
38 */
39typedef struct
40{
41  int hashsize;
42  partial_path* items[FSH_HASHSIZE];
43  srec* rec;
44}
45FixedSizeHash;
46
47void hash_init(FixedSizeHash* hash, srec* rec);
48int hash_del(FixedSizeHash* hash, partial_path* parp);
49unsigned int hashfunc(partial_path* parp);
50int compare_parp(partial_path* parp1, partial_path* parp2, srec* rec);
51int hash_get(FixedSizeHash* hash, partial_path* parp, void** hval);
52int hash_set(FixedSizeHash* hash, partial_path* parp);
53
54#endif
55