rculfqueue: LGPL-ize
[urcu.git] / urcu / hlist.h
1 #ifndef _KCOMPAT_HLIST_H
2 #define _KCOMPAT_HLIST_H
3
4 /*
5 * Kernel sourcecode compatible lightweight single pointer list head useful
6 * for implementing hash tables
7 *
8 * Copyright (C) 2009 Novell Inc.
9 *
10 * Author: Jan Blunck <jblunck@suse.de>
11 *
12 * Copyright (C) 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
13 *
14 * This program is free software; you can redistribute it and/or modify it
15 * under the terms of the GNU Lesser General Public License version 2.1 as
16 * published by the Free Software Foundation.
17 */
18
19 struct hlist_head
20 {
21 struct hlist_node *next;
22 };
23
24 struct hlist_node
25 {
26 struct hlist_node *next;
27 struct hlist_node *prev;
28 };
29
30 /* Initialize a new list head. */
31 static inline void INIT_HLIST_HEAD(struct hlist_head *ptr)
32 {
33 ptr->next = NULL;
34 }
35
36 /* Get typed element from list at a given position. */
37 #define hlist_entry(ptr, type, member) \
38 ((type *) ((char *) (ptr) - (unsigned long) (&((type *) 0)->member)))
39
40 /* Add new element at the head of the list. */
41 static inline void hlist_add_head (struct hlist_node *newp,
42 struct hlist_head *head)
43 {
44 if (head->next)
45 head->next->prev = newp;
46
47 newp->next = head->next;
48 newp->prev = (struct hlist_node *)head;
49 head->next = newp;
50 }
51
52 /* Remove element from list. */
53 static inline void hlist_del (struct hlist_node *elem)
54 {
55 if (elem->next)
56 elem->next->prev = elem->prev;
57
58 elem->prev->next = elem->next;
59 }
60
61 #define hlist_for_each_entry(entry, pos, head, member) \
62 for (pos = (head)->next, \
63 entry = hlist_entry(pos, typeof(*entry), member); \
64 pos != NULL; \
65 pos = pos->next, \
66 entry = hlist_entry(pos, typeof(*entry), member))
67
68 #define hlist_for_each_entry_safe(entry, pos, p, head, member) \
69 for (pos = (head)->next, \
70 entry = hlist_entry(pos, typeof(*entry), member); \
71 (pos != NULL) && ({ p = pos->next; 1;}); \
72 pos = p, \
73 entry = hlist_entry(pos, typeof(*entry), member))
74
75 #endif /* _KCOMPAT_HLIST_H */
This page took 0.040198 seconds and 4 git commands to generate.