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    uint64_t size_magic;
55    uint64_t rehash_magic;
56    uint32_t max_entries;
57    uint32_t size_index;
58    uint32_t entries;
59    uint32_t deleted_entries;
60 };
61 
62 struct hash_table *
63 _mesa_hash_table_create(void *mem_ctx,
64                         uint32_t (*key_hash_function)(const void *key),
65                         bool (*key_equals_function)(const void *a,
66                                                     const void *b));
67 
68 bool
69 _mesa_hash_table_init(struct hash_table *ht,
70                       void *mem_ctx,
71                       uint32_t (*key_hash_function)(const void *key),
72                       bool (*key_equals_function)(const void *a,
73                                                   const void *b));
74 
75 struct hash_table *
76 _mesa_hash_table_create_u32_keys(void *mem_ctx);
77 
78 struct hash_table *
79 _mesa_hash_table_clone(struct hash_table *src, void *dst_mem_ctx);
80 void _mesa_hash_table_destroy(struct hash_table *ht,
81                               void (*delete_function)(struct hash_entry *entry));
82 void _mesa_hash_table_clear(struct hash_table *ht,
83                             void (*delete_function)(struct hash_entry *entry));
84 void _mesa_hash_table_set_deleted_key(struct hash_table *ht,
85                                       const void *deleted_key);
86 
_mesa_hash_table_num_entries(struct hash_table * ht)87 static inline uint32_t _mesa_hash_table_num_entries(struct hash_table *ht)
88 {
89    return ht->entries;
90 }
91 
92 struct hash_entry *
93 _mesa_hash_table_insert(struct hash_table *ht, const void *key, void *data);
94 struct hash_entry *
95 _mesa_hash_table_insert_pre_hashed(struct hash_table *ht, uint32_t hash,
96                                    const void *key, void *data);
97 struct hash_entry *
98 _mesa_hash_table_search(struct hash_table *ht, const void *key);
99 struct hash_entry *
100 _mesa_hash_table_search_pre_hashed(struct hash_table *ht, uint32_t hash,
101                                   const void *key);
102 void _mesa_hash_table_remove(struct hash_table *ht,
103                              struct hash_entry *entry);
104 void _mesa_hash_table_remove_key(struct hash_table *ht,
105                                  const void *key);
106 
107 struct hash_entry *_mesa_hash_table_next_entry(struct hash_table *ht,
108                                                struct hash_entry *entry);
109 struct hash_entry *_mesa_hash_table_next_entry_unsafe(const struct hash_table *ht,
110                                                struct hash_entry *entry);
111 struct hash_entry *
112 _mesa_hash_table_random_entry(struct hash_table *ht,
113                               bool (*predicate)(struct hash_entry *entry));
114 
115 uint32_t _mesa_hash_data(const void *data, size_t size);
116 uint32_t _mesa_hash_data_with_seed(const void *data, size_t size, uint32_t seed);
117 
118 uint32_t _mesa_hash_int(const void *key);
119 uint32_t _mesa_hash_uint(const void *key);
120 uint32_t _mesa_hash_u32(const void *key);
121 uint32_t _mesa_hash_string(const void *key);
122 uint32_t _mesa_hash_pointer(const void *pointer);
123 
124 bool _mesa_key_int_equal(const void *a, const void *b);
125 bool _mesa_key_uint_equal(const void *a, const void *b);
126 bool _mesa_key_u32_equal(const void *a, const void *b);
127 bool _mesa_key_string_equal(const void *a, const void *b);
128 bool _mesa_key_pointer_equal(const void *a, const void *b);
129 
130 struct hash_table *
131 _mesa_pointer_hash_table_create(void *mem_ctx);
132 
133 bool
134 _mesa_hash_table_reserve(struct hash_table *ht, unsigned size);
135 /**
136  * This foreach function is safe against deletion (which just replaces
137  * an entry's data with the deleted marker), but not against insertion
138  * (which may rehash the table, making entry a dangling pointer).
139  */
140 #define hash_table_foreach(ht, entry)                                      \
141    for (struct hash_entry *entry = _mesa_hash_table_next_entry(ht, NULL);  \
142         entry != NULL;                                                     \
143         entry = _mesa_hash_table_next_entry(ht, entry))
144 /**
145  * This foreach function destroys the table as it iterates.
146  * It is not safe to use when inserting or removing entries.
147  */
148 #define hash_table_foreach_remove(ht, entry)                                      \
149    for (struct hash_entry *entry = _mesa_hash_table_next_entry_unsafe(ht, NULL);  \
150         (ht)->entries;                                                     \
151         entry->hash = 0, entry->key = (void*)NULL, entry->data = NULL,      \
152         (ht)->entries--, entry = _mesa_hash_table_next_entry_unsafe(ht, entry))
153 
154 static inline void
hash_table_call_foreach(struct hash_table * ht,void (* callback)(const void * key,void * data,void * closure),void * closure)155 hash_table_call_foreach(struct hash_table *ht,
156                         void (*callback)(const void *key,
157                                          void *data,
158                                          void *closure),
159                         void *closure)
160 {
161    hash_table_foreach(ht, entry)
162       callback(entry->key, entry->data, closure);
163 }
164 
165 /**
166  * Hash table wrapper which supports 64-bit keys.
167  */
168 struct hash_table_u64 {
169    struct hash_table *table;
170    void *freed_key_data;
171    void *deleted_key_data;
172 };
173 
174 struct hash_table_u64 *
175 _mesa_hash_table_u64_create(void *mem_ctx);
176 
177 void
178 _mesa_hash_table_u64_destroy(struct hash_table_u64 *ht);
179 
180 void
181 _mesa_hash_table_u64_insert(struct hash_table_u64 *ht, uint64_t key,
182                             void *data);
183 
184 void *
185 _mesa_hash_table_u64_search(struct hash_table_u64 *ht, uint64_t key);
186 
187 void
188 _mesa_hash_table_u64_remove(struct hash_table_u64 *ht, uint64_t key);
189 
190 void
191 _mesa_hash_table_u64_clear(struct hash_table_u64 *ht);
192 
193 #ifdef __cplusplus
194 } /* extern C */
195 #endif
196 
197 #endif /* _HASH_TABLE_H */
198