xref: /freebsd/contrib/bmake/hash.h (revision 64a0982bee3db2236df43357e70ce8dddbc21d48)
1 /*	$NetBSD: hash.h,v 1.11 2016/06/07 00:40:00 sjg Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Adam de Boor.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	from: @(#)hash.h	8.1 (Berkeley) 6/6/93
34  */
35 
36 /*
37  * Copyright (c) 1988, 1989 by Adam de Boor
38  * Copyright (c) 1989 by Berkeley Softworks
39  * All rights reserved.
40  *
41  * This code is derived from software contributed to Berkeley by
42  * Adam de Boor.
43  *
44  * Redistribution and use in source and binary forms, with or without
45  * modification, are permitted provided that the following conditions
46  * are met:
47  * 1. Redistributions of source code must retain the above copyright
48  *    notice, this list of conditions and the following disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  * 3. All advertising materials mentioning features or use of this software
53  *    must display the following acknowledgement:
54  *	This product includes software developed by the University of
55  *	California, Berkeley and its contributors.
56  * 4. Neither the name of the University nor the names of its contributors
57  *    may be used to endorse or promote products derived from this software
58  *    without specific prior written permission.
59  *
60  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
61  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
62  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
63  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
64  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
65  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
66  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
67  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
68  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
69  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
70  * SUCH DAMAGE.
71  *
72  *	from: @(#)hash.h	8.1 (Berkeley) 6/6/93
73  */
74 
75 /* hash.h --
76  *
77  * 	This file contains definitions used by the hash module,
78  * 	which maintains hash tables.
79  */
80 
81 #ifndef	_HASH
82 #define	_HASH
83 
84 /*
85  * The following defines one entry in the hash table.
86  */
87 
88 typedef struct Hash_Entry {
89     struct Hash_Entry *next;		/* Used to link together all the
90     					 * entries associated with the same
91 					 * bucket. */
92     void	      *clientPtr;	/* Arbitrary pointer */
93     unsigned	      namehash;		/* hash value of key */
94     char	      name[1];		/* key string */
95 } Hash_Entry;
96 
97 typedef struct Hash_Table {
98     struct Hash_Entry **bucketPtr;/* Pointers to Hash_Entry, one
99     				 * for each bucket in the table. */
100     int 	size;		/* Actual size of array. */
101     int 	numEntries;	/* Number of entries in the table. */
102     int 	mask;		/* Used to select bits for hashing. */
103 } Hash_Table;
104 
105 /*
106  * The following structure is used by the searching routines
107  * to record where we are in the search.
108  */
109 
110 typedef struct Hash_Search {
111     Hash_Table  *tablePtr;	/* Table being searched. */
112     int 	nextIndex;	/* Next bucket to check (after current). */
113     Hash_Entry 	*hashEntryPtr;	/* Next entry to check in current bucket. */
114 } Hash_Search;
115 
116 /*
117  * Macros.
118  */
119 
120 /*
121  * void * Hash_GetValue(h)
122  *     Hash_Entry *h;
123  */
124 
125 #define Hash_GetValue(h) ((h)->clientPtr)
126 
127 /*
128  * Hash_SetValue(h, val);
129  *     Hash_Entry *h;
130  *     char *val;
131  */
132 
133 #define Hash_SetValue(h, val) ((h)->clientPtr = (val))
134 
135 /*
136  * Hash_Size(n) returns the number of words in an object of n bytes
137  */
138 
139 #define	Hash_Size(n)	(((n) + sizeof (int) - 1) / sizeof (int))
140 
141 void Hash_InitTable(Hash_Table *, int);
142 void Hash_DeleteTable(Hash_Table *);
143 Hash_Entry *Hash_FindEntry(Hash_Table *, const char *);
144 Hash_Entry *Hash_CreateEntry(Hash_Table *, const char *, Boolean *);
145 void Hash_DeleteEntry(Hash_Table *, Hash_Entry *);
146 Hash_Entry *Hash_EnumFirst(Hash_Table *, Hash_Search *);
147 Hash_Entry *Hash_EnumNext(Hash_Search *);
148 
149 #endif /* _HASH */
150