1 /* $NetBSD: hash.h,v 1.51 2024/07/07 09:37:00 rillig 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 tables with string keys and pointer values. */
76
77 #ifndef MAKE_HASH_H
78 #define MAKE_HASH_H
79
80 /* A single key-value entry in the hash table. */
81 typedef struct HashEntry {
82 struct HashEntry *next; /* Used to link together all the entries
83 * associated with the same bucket. */
84 void *value;
85 unsigned int hash; /* hash value of the key */
86 char key[1]; /* key string, variable length */
87 } HashEntry;
88
89 /* The hash table containing the entries. */
90 typedef struct HashTable {
91 HashEntry **buckets;
92 unsigned int bucketsSize;
93 unsigned int numEntries;
94 unsigned int bucketsMask; /* Used to select the bucket for a hash. */
95 } HashTable;
96
97 /* State of an iteration over all entries in a table. */
98 typedef struct HashIter {
99 HashTable *table; /* Table being searched. */
100 unsigned int nextBucket; /* Next bucket to check (after current). */
101 HashEntry *entry; /* Next entry to check in current bucket. */
102 } HashIter;
103
104 /* A set of strings. */
105 typedef struct HashSet {
106 HashTable tbl;
107 } HashSet;
108
109 MAKE_INLINE void * MAKE_ATTR_USE
HashEntry_Get(HashEntry * he)110 HashEntry_Get(HashEntry *he)
111 {
112 return he->value;
113 }
114
115 MAKE_INLINE void
HashEntry_Set(HashEntry * he,void * datum)116 HashEntry_Set(HashEntry *he, void *datum)
117 {
118 he->value = datum;
119 }
120
121 /* Set things up for iterating over all entries in the hash table. */
122 MAKE_INLINE void
HashIter_Init(HashIter * hi,HashTable * t)123 HashIter_Init(HashIter *hi, HashTable *t)
124 {
125 hi->table = t;
126 hi->nextBucket = 0;
127 hi->entry = NULL;
128 }
129
130 void HashTable_Init(HashTable *);
131 void HashTable_Done(HashTable *);
132 HashEntry *HashTable_FindEntry(HashTable *, const char *) MAKE_ATTR_USE;
133 void *HashTable_FindValue(HashTable *, const char *) MAKE_ATTR_USE;
134 unsigned int Hash_Substring(Substring) MAKE_ATTR_USE;
135 void *HashTable_FindValueBySubstringHash(HashTable *, Substring, unsigned int)
136 MAKE_ATTR_USE;
137 HashEntry *HashTable_CreateEntry(HashTable *, const char *, bool *);
138 void HashTable_Set(HashTable *, const char *, void *);
139 void HashTable_DeleteEntry(HashTable *, HashEntry *);
140 void HashTable_DebugStats(const HashTable *, const char *);
141
142 bool HashIter_Next(HashIter *) MAKE_ATTR_USE;
143
144 MAKE_INLINE void
HashSet_Init(HashSet * set)145 HashSet_Init(HashSet *set)
146 {
147 HashTable_Init(&set->tbl);
148 }
149
150 MAKE_INLINE void
HashSet_Done(HashSet * set)151 HashSet_Done(HashSet *set)
152 {
153 HashTable_Done(&set->tbl);
154 }
155
156 MAKE_INLINE bool
HashSet_Add(HashSet * set,const char * key)157 HashSet_Add(HashSet *set, const char *key)
158 {
159 bool isNew;
160
161 (void)HashTable_CreateEntry(&set->tbl, key, &isNew);
162 return isNew;
163 }
164
165 MAKE_INLINE bool MAKE_ATTR_USE
HashSet_Contains(HashSet * set,const char * key)166 HashSet_Contains(HashSet *set, const char *key)
167 {
168 return HashTable_FindEntry(&set->tbl, key) != NULL;
169 }
170
171 MAKE_INLINE void
HashIter_InitSet(HashIter * hi,HashSet * set)172 HashIter_InitSet(HashIter *hi, HashSet *set)
173 {
174 HashIter_Init(hi, &set->tbl);
175 }
176
177 #endif
178