xref: /openbmc/linux/net/batman-adv/hash.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * Copyright (C) 2006-2010 B.A.T.M.A.N. contributors:
3  *
4  * Simon Wunderlich, Marek Lindner
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of version 2 of the GNU General Public
8  * License as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18  * 02110-1301, USA
19  *
20  */
21 
22 #include "main.h"
23 #include "hash.h"
24 
25 /* clears the hash */
26 static void hash_init(struct hashtable_t *hash)
27 {
28 	int i;
29 
30 	for (i = 0 ; i < hash->size; i++)
31 		INIT_HLIST_HEAD(&hash->table[i]);
32 }
33 
34 /* free only the hashtable and the hash itself. */
35 void hash_destroy(struct hashtable_t *hash)
36 {
37 	kfree(hash->table);
38 	kfree(hash);
39 }
40 
41 /* allocates and clears the hash */
42 struct hashtable_t *hash_new(int size)
43 {
44 	struct hashtable_t *hash;
45 
46 	hash = kmalloc(sizeof(struct hashtable_t) , GFP_ATOMIC);
47 
48 	if (!hash)
49 		return NULL;
50 
51 	hash->size = size;
52 	hash->table = kmalloc(sizeof(struct element_t *) * size, GFP_ATOMIC);
53 
54 	if (!hash->table) {
55 		kfree(hash);
56 		return NULL;
57 	}
58 
59 	hash_init(hash);
60 
61 	return hash;
62 }
63