xref: /freebsd/sbin/rcorder/hash.h (revision 3c4ba5f55438f7afd4f4b0b56f88f2bb505fd6a6)
1 /*	$FreeBSD$	*/
2 /*	$NetBSD: hash.h,v 1.1.1.1 1999/11/19 04:30:56 mrg Exp $	*/
3 
4 /*-
5  * SPDX-License-Identifier: BSD-4-Clause
6  *
7  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
8  * Copyright (c) 1988, 1989 by Adam de Boor
9  * Copyright (c) 1989 by Berkeley Softworks
10  * All rights reserved.
11  *
12  * This code is derived from software contributed to Berkeley by
13  * Adam de Boor.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  * 3. All advertising materials mentioning features or use of this software
24  *    must display the following acknowledgement:
25  *	This product includes software developed by the University of
26  *	California, Berkeley and its contributors.
27  * 4. Neither the name of the University nor the names of its contributors
28  *    may be used to endorse or promote products derived from this software
29  *    without specific prior written permission.
30  *
31  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41  * SUCH DAMAGE.
42  *
43  *	from: @(#)hash.h	8.1 (Berkeley) 6/6/93
44  */
45 
46 /* hash.h --
47  *
48  * 	This file contains definitions used by the hash module,
49  * 	which maintains hash tables.
50  */
51 
52 #ifndef	_HASH
53 #define	_HASH
54 
55 /*
56  * The following defines one entry in the hash table.
57  */
58 
59 typedef struct Hash_Entry {
60 	struct	Hash_Entry *next;	/* Used to link together all the
61 					 * entries associated with the same
62 					 * bucket. */
63 	ClientData	clientData;	/* Arbitrary piece of data associated
64 					 * with key. */
65 	unsigned	namehash;	/* hash value of key */
66 	char		name[1];	/* key string */
67 } Hash_Entry;
68 
69 typedef struct Hash_Table {
70 	struct	Hash_Entry **bucketPtr;
71 				/* Pointers to Hash_Entry, one
72 				 * for each bucket in the table. */
73 	int 	size;		/* Actual size of array. */
74 	int 	numEntries;	/* Number of entries in the table. */
75 	int 	mask;		/* Used to select bits for hashing. */
76 } Hash_Table;
77 
78 /*
79  * The following structure is used by the searching routines
80  * to record where we are in the search.
81  */
82 
83 typedef struct Hash_Search {
84 	Hash_Table	*tablePtr;	/* Table being searched. */
85 	int	 	nextIndex;	/* Next bucket to check (after
86 					 * current). */
87 	Hash_Entry 	*hashEntryPtr;	/* Next entry to check in current
88 					 * bucket. */
89 } Hash_Search;
90 
91 /*
92  * Macros.
93  */
94 
95 /*
96  * ClientData Hash_GetValue(h)
97  *     Hash_Entry *h;
98  */
99 
100 #define Hash_GetValue(h) ((h)->clientData)
101 
102 /*
103  * Hash_SetValue(h, val);
104  *     Hash_Entry *h;
105  *     char *val;
106  */
107 
108 #define Hash_SetValue(h, val) ((h)->clientData = (ClientData) (val))
109 
110 #ifdef ORDER
111 /*
112  * Hash_GetKey(h);
113  *     Hash_Entry *h;
114  */
115 
116 #define Hash_GetKey(h) ((h)->name)
117 #endif /* ORDER */
118 
119 /*
120  * Hash_Size(n) returns the number of words in an object of n bytes
121  */
122 
123 #define	Hash_Size(n)	(((n) + sizeof (int) - 1) / sizeof (int))
124 
125 void Hash_InitTable(Hash_Table *, int);
126 void Hash_DeleteTable(Hash_Table *);
127 Hash_Entry *Hash_FindEntry(Hash_Table *, char *);
128 Hash_Entry *Hash_CreateEntry(Hash_Table *, char *, Boolean *);
129 void Hash_DeleteEntry(Hash_Table *, Hash_Entry *);
130 Hash_Entry *Hash_EnumFirst(Hash_Table *, Hash_Search *);
131 Hash_Entry *Hash_EnumNext(Hash_Search *);
132 
133 #endif /* _HASH */
134