[urcu.git] / urcu / hlist.h

#ifndef _KCOMPAT_HLIST_H
#define _KCOMPAT_HLIST_H

/*
 * Kernel sourcecode compatible lightweight single pointer list head useful
 * for implementing hash tables
 *
 * Copyright (C) 2009 Novell Inc.
 *
 * Author: Jan Blunck <jblunck@suse.de>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License version 2.1 as
 * published by the Free  Software Foundation.
 */

struct hlist_head
{
	struct hlist_node *next;
};

struct hlist_node
{
	struct hlist_node *next;
	struct hlist_node *prev;
};

/* Initialize a new list head.  */
static inline void  INIT_HLIST_HEAD(struct hlist_head *ptr)
{
	ptr->next = NULL;
}

/* Get typed element from list at a given position.  */
#define hlist_entry(ptr, type, member)					\
	((type *) ((char *) (ptr) - (unsigned long) (&((type *) 0)->member)))

/* Add new element at the head of the list.  */
static inline void hlist_add_head (struct hlist_node *newp,
				   struct hlist_head *head)
{
	if (head->next)
		head->next->prev = newp;

	newp->next = head->next;
	newp->prev = (struct hlist_node *)head;
	head->next = newp;
}

/* Remove element from list.  */
static inline void hlist_del (struct hlist_node *elem)
{
	if (elem->next)
		elem->next->prev = elem->prev;

	elem->prev->next = elem->next;
}

#define hlist_for_each_entry(entry, pos, head, member)			\
	for (pos = (head)->next,					\
		     entry = hlist_entry(pos, typeof(*entry), member);	\
	     pos != NULL;						\
	     pos = pos->next,					\
		     entry = hlist_entry(pos, typeof(*entry), member))

#define hlist_for_each_entry_safe(entry, pos, p, head, member)		\
	for (pos = (head)->next,					\
		     entry = hlist_entry(pos, typeof(*entry), member);	\
	     (pos != NULL) && ({ p = pos->next; 1;});			\
	     pos = p,							\
		     entry = hlist_entry(pos, typeof(*entry), member))

#endif	/* _KCOMPAT_HLIST_H */
Commit	Line	Data
63ff4873 MD	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	* This program is free software; you can redistribute it and/or modify it
	13	* under the terms of the GNU Lesser General Public License version 2.1 as
	14	* published by the Free Software Foundation.
	15	*/
	16
	17	struct hlist_head
	18	{
	19	struct hlist_node *next;
	20	};
	21
	22	struct hlist_node
	23	{
	24	struct hlist_node *next;
	25	struct hlist_node *prev;
	26	};
	27
	28	/* Initialize a new list head. */
	29	static inline void INIT_HLIST_HEAD(struct hlist_head *ptr)
	30	{
	31	ptr->next = NULL;
	32	}
	33
	34	/* Get typed element from list at a given position. */
	35	#define hlist_entry(ptr, type, member) \
	36	((type ) ((char ) (ptr) - (unsigned long) (&((type *) 0)->member)))
	37
	38	/* Add new element at the head of the list. */
	39	static inline void hlist_add_head (struct hlist_node *newp,
	40	struct hlist_head *head)
	41	{
	42	if (head->next)
	43	head->next->prev = newp;
	44
	45	newp->next = head->next;
	46	newp->prev = (struct hlist_node *)head;
	47	head->next = newp;
	48	}
	49
	50	/* Remove element from list. */
	51	static inline void hlist_del (struct hlist_node *elem)
	52	{
	53	if (elem->next)
	54	elem->next->prev = elem->prev;
	55
	56	elem->prev->next = elem->next;
	57	}
	58
	59	#define hlist_for_each_entry(entry, pos, head, member) \
	60	for (pos = (head)->next, \
	61	entry = hlist_entry(pos, typeof(*entry), member); \
	62	pos != NULL; \
	63	pos = pos->next, \
	64	entry = hlist_entry(pos, typeof(*entry), member))
65
66	#define hlist_for_each_entry_safe(entry, pos, p, head, member) \
67	for (pos = (head)->next, \
68	entry = hlist_entry(pos, typeof(*entry), member); \
69	(pos != NULL) && ({ p = pos->next; 1;}); \
70	pos = p, \
71	entry = hlist_entry(pos, typeof(*entry), member))
72
73	#endif /* _KCOMPAT_HLIST_H */