1 /**************************************************************************
2 *
3 * Copyright 2008 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28 /**
29 * @file
30 * General purpose hash table implementation.
31 *
32 * Just uses the cso_hash for now, but it might be better switch to a linear
33 * probing hash table implementation at some point -- as it is said they have
34 * better lookup and cache performance and it appears to be possible to write
35 * a lock-free implementation of such hash tables .
36 *
37 * @author José Fonseca <jfonseca@vmware.com>
38 */
39
40
41 #include "pipe/p_compiler.h"
42 #include "util/u_debug.h"
43
44 #include "cso_cache/cso_hash.h"
45
46 #include "util/u_memory.h"
47 #include "util/u_hash_table.h"
48
49
50 struct util_hash_table
51 {
52 struct cso_hash *cso;
53
54 /** Hash function */
55 unsigned (*hash)(void *key);
56
57 /** Compare two keys */
58 int (*compare)(void *key1, void *key2);
59
60 /* TODO: key, value destructors? */
61 };
62
63
64 struct util_hash_table_item
65 {
66 void *key;
67 void *value;
68 };
69
70
71 static inline struct util_hash_table_item *
util_hash_table_item(struct cso_hash_iter iter)72 util_hash_table_item(struct cso_hash_iter iter)
73 {
74 return (struct util_hash_table_item *)cso_hash_iter_data(iter);
75 }
76
77
78 struct util_hash_table *
util_hash_table_create(unsigned (* hash)(void * key),int (* compare)(void * key1,void * key2))79 util_hash_table_create(unsigned (*hash)(void *key),
80 int (*compare)(void *key1, void *key2))
81 {
82 struct util_hash_table *ht;
83
84 ht = MALLOC_STRUCT(util_hash_table);
85 if (!ht)
86 return NULL;
87
88 ht->cso = cso_hash_create();
89 if(!ht->cso) {
90 FREE(ht);
91 return NULL;
92 }
93
94 ht->hash = hash;
95 ht->compare = compare;
96
97 return ht;
98 }
99
100
101 static inline struct cso_hash_iter
util_hash_table_find_iter(struct util_hash_table * ht,void * key,unsigned key_hash)102 util_hash_table_find_iter(struct util_hash_table *ht,
103 void *key,
104 unsigned key_hash)
105 {
106 struct cso_hash_iter iter;
107 struct util_hash_table_item *item;
108
109 iter = cso_hash_find(ht->cso, key_hash);
110 while (!cso_hash_iter_is_null(iter)) {
111 item = (struct util_hash_table_item *)cso_hash_iter_data(iter);
112 if (!ht->compare(item->key, key))
113 break;
114 iter = cso_hash_iter_next(iter);
115 }
116
117 return iter;
118 }
119
120
121 static inline struct util_hash_table_item *
util_hash_table_find_item(struct util_hash_table * ht,void * key,unsigned key_hash)122 util_hash_table_find_item(struct util_hash_table *ht,
123 void *key,
124 unsigned key_hash)
125 {
126 struct cso_hash_iter iter;
127 struct util_hash_table_item *item;
128
129 iter = cso_hash_find(ht->cso, key_hash);
130 while (!cso_hash_iter_is_null(iter)) {
131 item = (struct util_hash_table_item *)cso_hash_iter_data(iter);
132 if (!ht->compare(item->key, key))
133 return item;
134 iter = cso_hash_iter_next(iter);
135 }
136
137 return NULL;
138 }
139
140
141 enum pipe_error
util_hash_table_set(struct util_hash_table * ht,void * key,void * value)142 util_hash_table_set(struct util_hash_table *ht,
143 void *key,
144 void *value)
145 {
146 unsigned key_hash;
147 struct util_hash_table_item *item;
148 struct cso_hash_iter iter;
149
150 assert(ht);
151 if (!ht)
152 return PIPE_ERROR_BAD_INPUT;
153
154 key_hash = ht->hash(key);
155
156 item = util_hash_table_find_item(ht, key, key_hash);
157 if (item) {
158 /* TODO: key/value destruction? */
159 item->value = value;
160 return PIPE_OK;
161 }
162
163 item = MALLOC_STRUCT(util_hash_table_item);
164 if (!item)
165 return PIPE_ERROR_OUT_OF_MEMORY;
166
167 item->key = key;
168 item->value = value;
169
170 iter = cso_hash_insert(ht->cso, key_hash, item);
171 if(cso_hash_iter_is_null(iter)) {
172 FREE(item);
173 return PIPE_ERROR_OUT_OF_MEMORY;
174 }
175
176 return PIPE_OK;
177 }
178
179
180 void *
util_hash_table_get(struct util_hash_table * ht,void * key)181 util_hash_table_get(struct util_hash_table *ht,
182 void *key)
183 {
184 unsigned key_hash;
185 struct util_hash_table_item *item;
186
187 assert(ht);
188 if (!ht)
189 return NULL;
190
191 key_hash = ht->hash(key);
192
193 item = util_hash_table_find_item(ht, key, key_hash);
194 if (!item)
195 return NULL;
196
197 return item->value;
198 }
199
200
201 void
util_hash_table_remove(struct util_hash_table * ht,void * key)202 util_hash_table_remove(struct util_hash_table *ht,
203 void *key)
204 {
205 unsigned key_hash;
206 struct cso_hash_iter iter;
207 struct util_hash_table_item *item;
208
209 assert(ht);
210 if (!ht)
211 return;
212
213 key_hash = ht->hash(key);
214
215 iter = util_hash_table_find_iter(ht, key, key_hash);
216 if(cso_hash_iter_is_null(iter))
217 return;
218
219 item = util_hash_table_item(iter);
220 assert(item);
221 FREE(item);
222
223 cso_hash_erase(ht->cso, iter);
224 }
225
226
227 void
util_hash_table_clear(struct util_hash_table * ht)228 util_hash_table_clear(struct util_hash_table *ht)
229 {
230 struct cso_hash_iter iter;
231 struct util_hash_table_item *item;
232
233 assert(ht);
234 if (!ht)
235 return;
236
237 iter = cso_hash_first_node(ht->cso);
238 while (!cso_hash_iter_is_null(iter)) {
239 item = (struct util_hash_table_item *)cso_hash_take(ht->cso, cso_hash_iter_key(iter));
240 FREE(item);
241 iter = cso_hash_first_node(ht->cso);
242 }
243 }
244
245
246 enum pipe_error
util_hash_table_foreach(struct util_hash_table * ht,enum pipe_error (* callback)(void * key,void * value,void * data),void * data)247 util_hash_table_foreach(struct util_hash_table *ht,
248 enum pipe_error (*callback)
249 (void *key, void *value, void *data),
250 void *data)
251 {
252 struct cso_hash_iter iter;
253 struct util_hash_table_item *item;
254 enum pipe_error result;
255
256 assert(ht);
257 if (!ht)
258 return PIPE_ERROR_BAD_INPUT;
259
260 iter = cso_hash_first_node(ht->cso);
261 while (!cso_hash_iter_is_null(iter)) {
262 item = (struct util_hash_table_item *)cso_hash_iter_data(iter);
263 result = callback(item->key, item->value, data);
264 if(result != PIPE_OK)
265 return result;
266 iter = cso_hash_iter_next(iter);
267 }
268
269 return PIPE_OK;
270 }
271
272
273 void
util_hash_table_destroy(struct util_hash_table * ht)274 util_hash_table_destroy(struct util_hash_table *ht)
275 {
276 struct cso_hash_iter iter;
277 struct util_hash_table_item *item;
278
279 assert(ht);
280 if (!ht)
281 return;
282
283 iter = cso_hash_first_node(ht->cso);
284 while (!cso_hash_iter_is_null(iter)) {
285 item = (struct util_hash_table_item *)cso_hash_iter_data(iter);
286 FREE(item);
287 iter = cso_hash_iter_next(iter);
288 }
289
290 cso_hash_delete(ht->cso);
291
292 FREE(ht);
293 }
294