1 /* $NetBSD: hash.h,v 1.41 2021/12/07 21:58:01 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 strings as keys and arbitrary pointers as 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 key_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; /* Pointers to HashEntry, one 92 * for each bucket in the table. */ 93 unsigned int bucketsSize; 94 unsigned int numEntries; /* Number of entries in the table. */ 95 unsigned int bucketsMask; /* Used to select the bucket for a hash. */ 96 unsigned int maxchain; /* max length of chain detected */ 97 } HashTable; 98 99 /* State of an iteration over all entries in a table. */ 100 typedef struct HashIter { 101 HashTable *table; /* Table being searched. */ 102 unsigned int nextBucket; /* Next bucket to check (after current). */ 103 HashEntry *entry; /* Next entry to check in current bucket. */ 104 } HashIter; 105 106 /* A set of strings. */ 107 typedef struct HashSet { 108 HashTable tbl; 109 } HashSet; 110 111 MAKE_INLINE void * 112 HashEntry_Get(HashEntry *h) 113 { 114 return h->value; 115 } 116 117 MAKE_INLINE void 118 HashEntry_Set(HashEntry *h, void *datum) 119 { 120 h->value = datum; 121 } 122 123 /* Set things up for iterating over all entries in the hash table. */ 124 MAKE_INLINE void 125 HashIter_Init(HashIter *hi, HashTable *t) 126 { 127 hi->table = t; 128 hi->nextBucket = 0; 129 hi->entry = NULL; 130 } 131 132 void HashTable_Init(HashTable *); 133 void HashTable_Done(HashTable *); 134 HashEntry *HashTable_FindEntry(HashTable *, const char *); 135 void *HashTable_FindValue(HashTable *, const char *); 136 unsigned int Hash_Substring(Substring); 137 void *HashTable_FindValueBySubstringHash(HashTable *, Substring, unsigned int); 138 HashEntry *HashTable_CreateEntry(HashTable *, const char *, bool *); 139 HashEntry *HashTable_Set(HashTable *, const char *, void *); 140 void HashTable_DeleteEntry(HashTable *, HashEntry *); 141 void HashTable_DebugStats(HashTable *, const char *); 142 143 void HashIter_Init(HashIter *, HashTable *); 144 HashEntry *HashIter_Next(HashIter *); 145 146 MAKE_INLINE void 147 HashSet_Init(HashSet *set) 148 { 149 HashTable_Init(&set->tbl); 150 } 151 152 MAKE_INLINE void 153 HashSet_Done(HashSet *set) 154 { 155 HashTable_Done(&set->tbl); 156 } 157 158 MAKE_INLINE bool 159 HashSet_Add(HashSet *set, const char *key) 160 { 161 bool isNew; 162 163 (void)HashTable_CreateEntry(&set->tbl, key, &isNew); 164 return isNew; 165 } 166 167 MAKE_INLINE bool 168 HashSet_Contains(HashSet *set, const char *key) 169 { 170 return HashTable_FindEntry(&set->tbl, key) != NULL; 171 } 172 173 MAKE_INLINE void 174 HashIter_InitSet(HashIter *hi, HashSet *set) 175 { 176 HashIter_Init(hi, &set->tbl); 177 } 178 179 #endif /* MAKE_HASH_H */ 180