1 /*
2 * Copyright © 2009,2012 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 * Eric Anholt <eric@anholt.net>
25 *
26 */
27
28 #ifndef _HASH_TABLE_H
29 #define _HASH_TABLE_H
30
31 #include <stdlib.h>
32 #include <inttypes.h>
33 #include <stdbool.h>
34 #include "c99_compat.h"
35 #include "macros.h"
36
37 #ifdef __cplusplus
38 extern "C" {
39 #endif
40
41 struct hash_entry {
42 uint32_t hash;
43 const void *key;
44 void *data;
45 };
46
47 struct hash_table {
48 struct hash_entry *table;
49 uint32_t (*key_hash_function)(const void *key);
50 bool (*key_equals_function)(const void *a, const void *b);
51 const void *deleted_key;
52 uint32_t size;
53 uint32_t rehash;
54 uint32_t max_entries;
55 uint32_t size_index;
56 uint32_t entries;
57 uint32_t deleted_entries;
58 };
59
60 struct hash_table *
61 _mesa_hash_table_create(void *mem_ctx,
62 uint32_t (*key_hash_function)(const void *key),
63 bool (*key_equals_function)(const void *a,
64 const void *b));
65 void _mesa_hash_table_destroy(struct hash_table *ht,
66 void (*delete_function)(struct hash_entry *entry));
67 void _mesa_hash_table_clear(struct hash_table *ht,
68 void (*delete_function)(struct hash_entry *entry));
69 void _mesa_hash_table_set_deleted_key(struct hash_table *ht,
70 const void *deleted_key);
71
_mesa_hash_table_num_entries(struct hash_table * ht)72 static inline uint32_t _mesa_hash_table_num_entries(struct hash_table *ht)
73 {
74 return ht->entries;
75 }
76
77 struct hash_entry *
78 _mesa_hash_table_insert(struct hash_table *ht, const void *key, void *data);
79 struct hash_entry *
80 _mesa_hash_table_insert_pre_hashed(struct hash_table *ht, uint32_t hash,
81 const void *key, void *data);
82 struct hash_entry *
83 _mesa_hash_table_search(struct hash_table *ht, const void *key);
84 struct hash_entry *
85 _mesa_hash_table_search_pre_hashed(struct hash_table *ht, uint32_t hash,
86 const void *key);
87 void _mesa_hash_table_remove(struct hash_table *ht,
88 struct hash_entry *entry);
89
90 struct hash_entry *_mesa_hash_table_next_entry(struct hash_table *ht,
91 struct hash_entry *entry);
92 struct hash_entry *
93 _mesa_hash_table_random_entry(struct hash_table *ht,
94 bool (*predicate)(struct hash_entry *entry));
95
96 uint32_t _mesa_hash_data(const void *data, size_t size);
97 uint32_t _mesa_hash_string(const void *key);
98 bool _mesa_key_string_equal(const void *a, const void *b);
99 bool _mesa_key_pointer_equal(const void *a, const void *b);
100
_mesa_key_hash_string(const void * key)101 static inline uint32_t _mesa_key_hash_string(const void *key)
102 {
103 return _mesa_hash_string((const char *)key);
104 }
105
_mesa_hash_pointer(const void * pointer)106 static inline uint32_t _mesa_hash_pointer(const void *pointer)
107 {
108 uintptr_t num = (uintptr_t) pointer;
109 return (uint32_t) ((num >> 2) ^ (num >> 6) ^ (num >> 10) ^ (num >> 14));
110 }
111
112 enum {
113 _mesa_fnv32_1a_offset_bias = 2166136261u,
114 };
115
116 static inline uint32_t
_mesa_fnv32_1a_accumulate_block(uint32_t hash,const void * data,size_t size)117 _mesa_fnv32_1a_accumulate_block(uint32_t hash, const void *data, size_t size)
118 {
119 const uint8_t *bytes = (const uint8_t *)data;
120
121 while (size-- != 0) {
122 hash ^= *bytes;
123 hash = hash * 0x01000193;
124 bytes++;
125 }
126
127 return hash;
128 }
129
130 #define _mesa_fnv32_1a_accumulate(hash, expr) \
131 _mesa_fnv32_1a_accumulate_block(hash, &(expr), sizeof(expr))
132
133 /**
134 * This foreach function is safe against deletion (which just replaces
135 * an entry's data with the deleted marker), but not against insertion
136 * (which may rehash the table, making entry a dangling pointer).
137 */
138 #define hash_table_foreach(ht, entry) \
139 for (entry = _mesa_hash_table_next_entry(ht, NULL); \
140 entry != NULL; \
141 entry = _mesa_hash_table_next_entry(ht, entry))
142
143 static inline void
hash_table_call_foreach(struct hash_table * ht,void (* callback)(const void * key,void * data,void * closure),void * closure)144 hash_table_call_foreach(struct hash_table *ht,
145 void (*callback)(const void *key,
146 void *data,
147 void *closure),
148 void *closure)
149 {
150 struct hash_entry *entry;
151
152 hash_table_foreach(ht, entry)
153 callback(entry->key, entry->data, closure);
154 }
155
156 /**
157 * Hash table wrapper which supports 64-bit keys.
158 */
159 struct hash_table_u64 {
160 struct hash_table *table;
161 void *deleted_key_data;
162 };
163
164 struct hash_table_u64 *
165 _mesa_hash_table_u64_create(void *mem_ctx);
166
167 void
168 _mesa_hash_table_u64_destroy(struct hash_table_u64 *ht,
169 void (*delete_function)(struct hash_entry *entry));
170
171 void
172 _mesa_hash_table_u64_insert(struct hash_table_u64 *ht, uint64_t key,
173 void *data);
174
175 void *
176 _mesa_hash_table_u64_search(struct hash_table_u64 *ht, uint64_t key);
177
178 void
179 _mesa_hash_table_u64_remove(struct hash_table_u64 *ht, uint64_t key);
180
181 #ifdef __cplusplus
182 } /* extern C */
183 #endif
184
185 #endif /* _HASH_TABLE_H */
186