xref: /freebsd/sbin/rcorder/hash.h (revision 5c52a79884070364bfc920fb8e492cfac61ec72f)
1 /*	$FreeBSD$	*/
2 /*	$NetBSD: hash.h,v 1.1.1.1 1999/11/19 04:30:56 mrg Exp $	*/
3 
4 /*
5  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
6  * Copyright (c) 1988, 1989 by Adam de Boor
7  * Copyright (c) 1989 by Berkeley Softworks
8  * All rights reserved.
9  *
10  * This code is derived from software contributed to Berkeley by
11  * Adam de Boor.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by the University of
24  *	California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *	from: @(#)hash.h	8.1 (Berkeley) 6/6/93
42  */
43 
44 /* hash.h --
45  *
46  * 	This file contains definitions used by the hash module,
47  * 	which maintains hash tables.
48  */
49 
50 #ifndef	_HASH
51 #define	_HASH
52 
53 /*
54  * The following defines one entry in the hash table.
55  */
56 
57 typedef struct Hash_Entry {
58 	struct	Hash_Entry *next;	/* Used to link together all the
59 					 * entries associated with the same
60 					 * bucket. */
61 	ClientData	clientData;	/* Arbitrary piece of data associated
62 					 * with key. */
63 	unsigned	namehash;	/* hash value of key */
64 	char		name[1];	/* key string */
65 } Hash_Entry;
66 
67 typedef struct Hash_Table {
68 	struct	Hash_Entry **bucketPtr;
69 				/* Pointers to Hash_Entry, one
70 				 * for each bucket in the table. */
71 	int 	size;		/* Actual size of array. */
72 	int 	numEntries;	/* Number of entries in the table. */
73 	int 	mask;		/* Used to select bits for hashing. */
74 } Hash_Table;
75 
76 /*
77  * The following structure is used by the searching routines
78  * to record where we are in the search.
79  */
80 
81 typedef struct Hash_Search {
82 	Hash_Table	*tablePtr;	/* Table being searched. */
83 	int	 	nextIndex;	/* Next bucket to check (after
84 					 * current). */
85 	Hash_Entry 	*hashEntryPtr;	/* Next entry to check in current
86 					 * bucket. */
87 } Hash_Search;
88 
89 /*
90  * Macros.
91  */
92 
93 /*
94  * ClientData Hash_GetValue(h)
95  *     Hash_Entry *h;
96  */
97 
98 #define Hash_GetValue(h) ((h)->clientData)
99 
100 /*
101  * Hash_SetValue(h, val);
102  *     Hash_Entry *h;
103  *     char *val;
104  */
105 
106 #define Hash_SetValue(h, val) ((h)->clientData = (ClientData) (val))
107 
108 #ifdef ORDER
109 /*
110  * Hash_GetKey(h);
111  *     Hash_Entry *h;
112  */
113 
114 #define Hash_GetKey(h) ((h)->name)
115 #endif /* ORDER */
116 
117 /*
118  * Hash_Size(n) returns the number of words in an object of n bytes
119  */
120 
121 #define	Hash_Size(n)	(((n) + sizeof (int) - 1) / sizeof (int))
122 
123 void Hash_InitTable(Hash_Table *, int);
124 void Hash_DeleteTable(Hash_Table *);
125 Hash_Entry *Hash_FindEntry(Hash_Table *, char *);
126 Hash_Entry *Hash_CreateEntry(Hash_Table *, char *, Boolean *);
127 void Hash_DeleteEntry(Hash_Table *, Hash_Entry *);
128 Hash_Entry *Hash_EnumFirst(Hash_Table *, Hash_Search *);
129 Hash_Entry *Hash_EnumNext(Hash_Search *);
130 
131 #endif /* _HASH */
132