1 /***
2 This file is part of avahi.
3
4 avahi is free software; you can redistribute it and/or modify it
5 under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation; either version 2.1 of the
7 License, or (at your option) any later version.
8
9 avahi is distributed in the hope that it will be useful, but WITHOUT
10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
12 Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with avahi; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
17 USA.
18 ***/
19
20 #ifdef HAVE_CONFIG_H
21 #include <config.h>
22 #endif
23
24 #include <stdlib.h>
25 #include <string.h>
26
27 #include <avahi-common/llist.h>
28 #include <avahi-common/domain.h>
29 #include "avahi-common/avahi-malloc.h"
30
31 #include "hashmap.h"
32 #include "util.h"
33
34 #define HASH_MAP_SIZE 123
35
36 typedef struct Entry Entry;
37 struct Entry {
38 AvahiHashmap *hashmap;
39 void *key;
40 void *value;
41
42 AVAHI_LLIST_FIELDS(Entry, bucket);
43 AVAHI_LLIST_FIELDS(Entry, entries);
44 };
45
46 struct AvahiHashmap {
47 AvahiHashFunc hash_func;
48 AvahiEqualFunc equal_func;
49 AvahiFreeFunc key_free_func, value_free_func;
50
51 Entry *entries[HASH_MAP_SIZE];
52 AVAHI_LLIST_HEAD(Entry, entries_list);
53 };
54
entry_get(AvahiHashmap * m,const void * key)55 static Entry* entry_get(AvahiHashmap *m, const void *key) {
56 unsigned idx;
57 Entry *e;
58
59 idx = m->hash_func(key) % HASH_MAP_SIZE;
60
61 for (e = m->entries[idx]; e; e = e->bucket_next)
62 if (m->equal_func(key, e->key))
63 return e;
64
65 return NULL;
66 }
67
entry_free(AvahiHashmap * m,Entry * e,int stolen)68 static void entry_free(AvahiHashmap *m, Entry *e, int stolen) {
69 unsigned idx;
70 assert(m);
71 assert(e);
72
73 idx = m->hash_func(e->key) % HASH_MAP_SIZE;
74
75 AVAHI_LLIST_REMOVE(Entry, bucket, m->entries[idx], e);
76 AVAHI_LLIST_REMOVE(Entry, entries, m->entries_list, e);
77
78 if (m->key_free_func)
79 m->key_free_func(e->key);
80 if (m->value_free_func && !stolen)
81 m->value_free_func(e->value);
82
83 avahi_free(e);
84 }
85
avahi_hashmap_new(AvahiHashFunc hash_func,AvahiEqualFunc equal_func,AvahiFreeFunc key_free_func,AvahiFreeFunc value_free_func)86 AvahiHashmap* avahi_hashmap_new(AvahiHashFunc hash_func, AvahiEqualFunc equal_func, AvahiFreeFunc key_free_func, AvahiFreeFunc value_free_func) {
87 AvahiHashmap *m;
88
89 assert(hash_func);
90 assert(equal_func);
91
92 if (!(m = avahi_new0(AvahiHashmap, 1)))
93 return NULL;
94
95 m->hash_func = hash_func;
96 m->equal_func = equal_func;
97 m->key_free_func = key_free_func;
98 m->value_free_func = value_free_func;
99
100 AVAHI_LLIST_HEAD_INIT(Entry, m->entries_list);
101
102 return m;
103 }
104
avahi_hashmap_free(AvahiHashmap * m)105 void avahi_hashmap_free(AvahiHashmap *m) {
106 assert(m);
107
108 while (m->entries_list)
109 entry_free(m, m->entries_list, 0);
110
111 avahi_free(m);
112 }
113
avahi_hashmap_lookup(AvahiHashmap * m,const void * key)114 void* avahi_hashmap_lookup(AvahiHashmap *m, const void *key) {
115 Entry *e;
116
117 assert(m);
118
119 if (!(e = entry_get(m, key)))
120 return NULL;
121
122 return e->value;
123 }
124
avahi_hashmap_insert(AvahiHashmap * m,void * key,void * value)125 int avahi_hashmap_insert(AvahiHashmap *m, void *key, void *value) {
126 unsigned idx;
127 Entry *e;
128
129 assert(m);
130
131 if ((e = entry_get(m, key))) {
132 if (m->key_free_func)
133 m->key_free_func(key);
134 if (m->value_free_func)
135 m->value_free_func(value);
136
137 return 1;
138 }
139
140 if (!(e = avahi_new(Entry, 1)))
141 return -1;
142
143 e->hashmap = m;
144 e->key = key;
145 e->value = value;
146
147 AVAHI_LLIST_PREPEND(Entry, entries, m->entries_list, e);
148
149 idx = m->hash_func(key) % HASH_MAP_SIZE;
150 AVAHI_LLIST_PREPEND(Entry, bucket, m->entries[idx], e);
151
152 return 0;
153 }
154
155
avahi_hashmap_replace(AvahiHashmap * m,void * key,void * value)156 int avahi_hashmap_replace(AvahiHashmap *m, void *key, void *value) {
157 unsigned idx;
158 Entry *e;
159
160 assert(m);
161
162 if ((e = entry_get(m, key))) {
163 if (m->key_free_func)
164 m->key_free_func(e->key);
165 if (m->value_free_func)
166 m->value_free_func(e->value);
167
168 e->key = key;
169 e->value = value;
170
171 return 1;
172 }
173
174 if (!(e = avahi_new(Entry, 1)))
175 return -1;
176
177 e->hashmap = m;
178 e->key = key;
179 e->value = value;
180
181 AVAHI_LLIST_PREPEND(Entry, entries, m->entries_list, e);
182
183 idx = m->hash_func(key) % HASH_MAP_SIZE;
184 AVAHI_LLIST_PREPEND(Entry, bucket, m->entries[idx], e);
185
186 return 0;
187 }
188
avahi_hashmap_remove(AvahiHashmap * m,const void * key)189 void avahi_hashmap_remove(AvahiHashmap *m, const void *key) {
190 Entry *e;
191
192 assert(m);
193
194 if (!(e = entry_get(m, key)))
195 return;
196
197 entry_free(m, e, 0);
198 }
199
avahi_hashmap_foreach(AvahiHashmap * m,AvahiHashmapForeachCallback callback,void * userdata)200 void avahi_hashmap_foreach(AvahiHashmap *m, AvahiHashmapForeachCallback callback, void *userdata) {
201 Entry *e, *next;
202 assert(m);
203 assert(callback);
204
205 for (e = m->entries_list; e; e = next) {
206 next = e->entries_next;
207
208 callback(e->key, e->value, userdata);
209 }
210 }
211
avahi_string_hash(const void * data)212 unsigned avahi_string_hash(const void *data) {
213 const char *p = data;
214 unsigned hash = 0;
215
216 assert(p);
217
218 for (; *p; p++)
219 hash = 31 * hash + *p;
220
221 return hash;
222 }
223
avahi_string_equal(const void * a,const void * b)224 int avahi_string_equal(const void *a, const void *b) {
225 const char *p = a, *q = b;
226
227 assert(p);
228 assert(q);
229
230 return strcmp(p, q) == 0;
231 }
232
avahi_int_hash(const void * data)233 unsigned avahi_int_hash(const void *data) {
234 const int *i = data;
235
236 assert(i);
237
238 return (unsigned) *i;
239 }
240
avahi_int_equal(const void * a,const void * b)241 int avahi_int_equal(const void *a, const void *b) {
242 const int *_a = a, *_b = b;
243
244 assert(_a);
245 assert(_b);
246
247 return *_a == *_b;
248 }
249