[userspace-rcu.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>
 *
 * Copyright (C) 2010-2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * 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.
 */

#include <stddef.h>

struct cds_hlist_head {
	struct cds_hlist_node *next;
};

struct cds_hlist_node {
	struct cds_hlist_node *next, *prev;
};

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

#define CDS_HLIST_HEAD(name) \
	struct cds_hlist_head name = { NULL }

#define CDS_HLIST_HEAD_INIT(name) \
	{ .next = NULL }

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

/* Get first entry from a list. Assumes the hlist is not empty. */
#define cds_hlist_first_entry(ptr, type, member) \
	cds_list_entry((ptr)->next, type, member)

static inline
int cds_hlist_empty(struct cds_hlist_head *head)
{
	return !head->next;
}

/* Add new element at the head of the list. */
static inline
void cds_hlist_add_head(struct cds_hlist_node *newp,
		struct cds_hlist_head *head)
{
	if (head->next)
		head->next->prev = newp;
	newp->next = head->next;
	newp->prev = (struct cds_hlist_node *) head;
	head->next = newp;
}

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

#define cds_hlist_for_each(pos, head) \
	for (pos = (head)->next; pos != NULL; pos = pos->next)

#define cds_hlist_for_each_safe(pos, p, head) \
	for (pos = (head)->next; \
		(pos != NULL) && (p = pos->next, 1); \
		pos = p)

/*
 * cds_hlist_for_each_entry and cds_hlist_for_each_entry_safe take
 * respectively 4 and 5 arguments, while the Linux kernel APIs take 3,
 * and 4. We implement cds_hlist_for_each_entry_2() and
 * cds_hlist_for_each_entry_safe_2() to follow the Linux kernel APIs.
 */
#define cds_hlist_for_each_entry(entry, pos, head, member) \
	for (pos = (head)->next, \
			entry = cds_hlist_entry(pos, __typeof__(*entry), member); \
		pos != NULL; \
		pos = pos->next, \
			entry = cds_hlist_entry(pos, __typeof__(*entry), member))

#define cds_hlist_for_each_entry_safe(entry, pos, p, head, member) \
	for (pos = (head)->next, \
			entry = cds_hlist_entry(pos, __typeof__(*entry), member); \
		(pos != NULL) && (p = pos->next, 1); \
		pos = p, \
			entry = cds_hlist_entry(pos, __typeof__(*entry), member))

#define cds_hlist_for_each_entry_2(entry, head, member) \
	for (entry = ((head)->next == NULL ? NULL \
			: cds_hlist_entry((head)->next, __typeof__(*entry), member)); \
		entry != NULL; \
		entry = (entry->member.next == NULL ? NULL \
			: cds_hlist_entry(entry->member.next, __typeof__(*entry), member)))

#define cds_hlist_for_each_entry_safe_2(entry, e, head, member) \
	for (entry = ((head)->next == NULL ? NULL \
			: cds_hlist_entry((head)->next, __typeof__(*entry), member)); \
		(entry != NULL) && (e = (entry->member.next == NULL ? NULL \
					: cds_hlist_entry(entry->member.next, \
						__typeof__(*entry), member)), 1); \
		entry = e)

#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	*
6734fec1	12	* Copyright (C) 2010-2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
5db941e8	13	*
63ff4873 MD	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
9056e3b8 MD	19	#include <stddef.h>
9056e3b8 MD	20
6734fec1	21	struct cds_hlist_head {
16aa9ee8	22	struct cds_hlist_node *next;
63ff4873 MD	23	};
63ff4873 MD	24
6734fec1 MD	25	struct cds_hlist_node {
6734fec1 MD	26	struct cds_hlist_node next, prev;
63ff4873 MD	27	};
63ff4873 MD	28
6734fec1 MD	29	/* Initialize a new list head. */
	30	static inline
	31	void CDS_INIT_HLIST_HEAD(struct cds_hlist_head *ptr)
63ff4873 MD	32	{
	33	ptr->next = NULL;
	34	}
	35
d7a0f2fe MD	36	#define CDS_HLIST_HEAD(name) \
	37	struct cds_hlist_head name = { NULL }
	38
	39	#define CDS_HLIST_HEAD_INIT(name) \
	40	{ .next = NULL }
	41
6734fec1 MD	42	/* Get typed element from list at a given position. */
6734fec1 MD	43	#define cds_hlist_entry(ptr, type, member) \
63ff4873 MD	44	((type ) ((char ) (ptr) - (unsigned long) (&((type *) 0)->member)))
63ff4873 MD	45
3d8fe307 MD	46	/* Get first entry from a list. Assumes the hlist is not empty. */
	47	#define cds_hlist_first_entry(ptr, type, member) \
	48	cds_list_entry((ptr)->next, type, member)
	49
9f446823 MD	50	static inline
9f446823 MD	51	int cds_hlist_empty(struct cds_hlist_head *head)
5f1bf177 MD	52	{
	53	return !head->next;
	54	}
	55
6734fec1 MD	56	/* Add new element at the head of the list. */
	57	static inline
	58	void cds_hlist_add_head(struct cds_hlist_node *newp,
	59	struct cds_hlist_head *head)
63ff4873 MD	60	{
	61	if (head->next)
	62	head->next->prev = newp;
63ff4873	63	newp->next = head->next;
6734fec1	64	newp->prev = (struct cds_hlist_node *) head;
63ff4873 MD	65	head->next = newp;
	66	}
	67
6734fec1 MD	68	/* Remove element from list. */
	69	static inline
	70	void cds_hlist_del(struct cds_hlist_node *elem)
63ff4873 MD	71	{
	72	if (elem->next)
	73	elem->next->prev = elem->prev;
63ff4873 MD	74	elem->prev->next = elem->next;
	75	}
	76
d7a0f2fe MD	77	#define cds_hlist_for_each(pos, head) \
	78	for (pos = (head)->next; pos != NULL; pos = pos->next)
	79
	80	#define cds_hlist_for_each_safe(pos, p, head) \
	81	for (pos = (head)->next; \
	82	(pos != NULL) && (p = pos->next, 1); \
	83	pos = p)
	84
	85	/*
	86	* cds_hlist_for_each_entry and cds_hlist_for_each_entry_safe take
	87	* respectively 4 and 5 arguments, while the Linux kernel APIs take 3,
	88	* and 4. We implement cds_hlist_for_each_entry_2() and
	89	* cds_hlist_for_each_entry_safe_2() to follow the Linux kernel APIs.
	90	*/
6734fec1 MD	91	#define cds_hlist_for_each_entry(entry, pos, head, member) \
	92	for (pos = (head)->next, \
	93	entry = cds_hlist_entry(pos, __typeof__(*entry), member); \
	94	pos != NULL; \
	95	pos = pos->next, \
	96	entry = cds_hlist_entry(pos, __typeof__(*entry), member))
63ff4873	97
6734fec1 MD	98	#define cds_hlist_for_each_entry_safe(entry, pos, p, head, member) \
	99	for (pos = (head)->next, \
	100	entry = cds_hlist_entry(pos, __typeof__(*entry), member); \
d7a0f2fe	101	(pos != NULL) && (p = pos->next, 1); \
6734fec1 MD	102	pos = p, \
6734fec1 MD	103	entry = cds_hlist_entry(pos, __typeof__(*entry), member))
63ff4873	104
d7a0f2fe	105	#define cds_hlist_for_each_entry_2(entry, head, member) \
db903109 MD	106	for (entry = ((head)->next == NULL ? NULL \
	107	: cds_hlist_entry((head)->next, __typeof__(*entry), member)); \
	108	entry != NULL; \
	109	entry = (entry->member.next == NULL ? NULL \
	110	: cds_hlist_entry(entry->member.next, __typeof__(*entry), member)))
d7a0f2fe MD	111
d7a0f2fe MD	112	#define cds_hlist_for_each_entry_safe_2(entry, e, head, member) \
db903109 MD	113	for (entry = ((head)->next == NULL ? NULL \
	114	: cds_hlist_entry((head)->next, __typeof__(*entry), member)); \
	115	(entry != NULL) && (e = (entry->member.next == NULL ? NULL \
	116	: cds_hlist_entry(entry->member.next, \
79efd9b3	117	__typeof__(*entry), member)), 1); \
d7a0f2fe	118	entry = e)
63ff4873 MD	119
63ff4873 MD	120	#endif /* _KCOMPAT_HLIST_H */