[openssh.git] / openbsd-compat / sys-queue.h

/*	$OpenBSD: queue.h,v 1.27 2005/02/25 13:29:30 deraadt Exp $	*/
/*	$NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $	*/

/*
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)queue.h	8.5 (Berkeley) 8/20/94
 */

/* OPENBSD ORIGINAL: sys/sys/queue.h */

#ifndef	_FAKE_QUEUE_H_
#define	_FAKE_QUEUE_H_

/*
 * Require for OS/X and other platforms that have old/broken/incomplete
 * <sys/queue.h>.
 */
#undef SLIST_HEAD
#undef SLIST_HEAD_INITIALIZER
#undef SLIST_ENTRY
#undef SLIST_FOREACH_PREVPTR
#undef SLIST_FIRST
#undef SLIST_END
#undef SLIST_EMPTY
#undef SLIST_NEXT
#undef SLIST_FOREACH
#undef SLIST_INIT
#undef SLIST_INSERT_AFTER
#undef SLIST_INSERT_HEAD
#undef SLIST_REMOVE_HEAD
#undef SLIST_REMOVE
#undef SLIST_REMOVE_NEXT
#undef LIST_HEAD
#undef LIST_HEAD_INITIALIZER
#undef LIST_ENTRY
#undef LIST_FIRST
#undef LIST_END
#undef LIST_EMPTY
#undef LIST_NEXT
#undef LIST_FOREACH
#undef LIST_INIT
#undef LIST_INSERT_AFTER
#undef LIST_INSERT_BEFORE
#undef LIST_INSERT_HEAD
#undef LIST_REMOVE
#undef LIST_REPLACE
#undef SIMPLEQ_HEAD
#undef SIMPLEQ_HEAD_INITIALIZER
#undef SIMPLEQ_ENTRY
#undef SIMPLEQ_FIRST
#undef SIMPLEQ_END
#undef SIMPLEQ_EMPTY
#undef SIMPLEQ_NEXT
#undef SIMPLEQ_FOREACH
#undef SIMPLEQ_INIT
#undef SIMPLEQ_INSERT_HEAD
#undef SIMPLEQ_INSERT_TAIL
#undef SIMPLEQ_INSERT_AFTER
#undef SIMPLEQ_REMOVE_HEAD
#undef TAILQ_HEAD
#undef TAILQ_HEAD_INITIALIZER
#undef TAILQ_ENTRY
#undef TAILQ_FIRST
#undef TAILQ_END
#undef TAILQ_NEXT
#undef TAILQ_LAST
#undef TAILQ_PREV
#undef TAILQ_EMPTY
#undef TAILQ_FOREACH
#undef TAILQ_FOREACH_REVERSE
#undef TAILQ_INIT
#undef TAILQ_INSERT_HEAD
#undef TAILQ_INSERT_TAIL
#undef TAILQ_INSERT_AFTER
#undef TAILQ_INSERT_BEFORE
#undef TAILQ_REMOVE
#undef TAILQ_REPLACE
#undef CIRCLEQ_HEAD
#undef CIRCLEQ_HEAD_INITIALIZER
#undef CIRCLEQ_ENTRY
#undef CIRCLEQ_FIRST
#undef CIRCLEQ_LAST
#undef CIRCLEQ_END
#undef CIRCLEQ_NEXT
#undef CIRCLEQ_PREV
#undef CIRCLEQ_EMPTY
#undef CIRCLEQ_FOREACH
#undef CIRCLEQ_FOREACH_REVERSE
#undef CIRCLEQ_INIT
#undef CIRCLEQ_INSERT_AFTER
#undef CIRCLEQ_INSERT_BEFORE
#undef CIRCLEQ_INSERT_HEAD
#undef CIRCLEQ_INSERT_TAIL
#undef CIRCLEQ_REMOVE
#undef CIRCLEQ_REPLACE

/*
 * This file defines five types of data structures: singly-linked lists, 
 * lists, simple queues, tail queues, and circular queues.
 *
 *
 * A singly-linked list is headed by a single forward pointer. The elements
 * are singly linked for minimum space and pointer manipulation overhead at
 * the expense of O(n) removal for arbitrary elements. New elements can be
 * added to the list after an existing element or at the head of the list.
 * Elements being removed from the head of the list should use the explicit
 * macro for this purpose for optimum efficiency. A singly-linked list may
 * only be traversed in the forward direction.  Singly-linked lists are ideal
 * for applications with large datasets and few or no removals or for
 * implementing a LIFO queue.
 *
 * A list is headed by a single forward pointer (or an array of forward
 * pointers for a hash table header). The elements are doubly linked
 * so that an arbitrary element can be removed without a need to
 * traverse the list. New elements can be added to the list before
 * or after an existing element or at the head of the list. A list
 * may only be traversed in the forward direction.
 *
 * A simple queue is headed by a pair of pointers, one the head of the
 * list and the other to the tail of the list. The elements are singly
 * linked to save space, so elements can only be removed from the
 * head of the list. New elements can be added to the list before or after
 * an existing element, at the head of the list, or at the end of the
 * list. A simple queue may only be traversed in the forward direction.
 *
 * A tail queue is headed by a pair of pointers, one to the head of the
 * list and the other to the tail of the list. The elements are doubly
 * linked so that an arbitrary element can be removed without a need to
 * traverse the list. New elements can be added to the list before or
 * after an existing element, at the head of the list, or at the end of
 * the list. A tail queue may be traversed in either direction.
 *
 * A circle queue is headed by a pair of pointers, one to the head of the
 * list and the other to the tail of the list. The elements are doubly
 * linked so that an arbitrary element can be removed without a need to
 * traverse the list. New elements can be added to the list before or after
 * an existing element, at the head of the list, or at the end of the list.
 * A circle queue may be traversed in either direction, but has a more
 * complex end of list detection.
 *
 * For details on the use of these macros, see the queue(3) manual page.
 */

/*
 * Singly-linked List definitions.
 */
#define SLIST_HEAD(name, type)						\
struct name {								\
	struct type *slh_first;	/* first element */			\
}
 
#define	SLIST_HEAD_INITIALIZER(head)					\
	{ NULL }
 
#define SLIST_ENTRY(type)						\
struct {								\
	struct type *sle_next;	/* next element */			\
}
 
/*
 * Singly-linked List access methods.
 */
#define	SLIST_FIRST(head)	((head)->slh_first)
#define	SLIST_END(head)		NULL
#define	SLIST_EMPTY(head)	(SLIST_FIRST(head) == SLIST_END(head))
#define	SLIST_NEXT(elm, field)	((elm)->field.sle_next)

#define	SLIST_FOREACH(var, head, field)					\
	for((var) = SLIST_FIRST(head);					\
	    (var) != SLIST_END(head);					\
	    (var) = SLIST_NEXT(var, field))

#define	SLIST_FOREACH_PREVPTR(var, varp, head, field)			\
	for ((varp) = &SLIST_FIRST((head));				\
	    ((var) = *(varp)) != SLIST_END(head);			\
	    (varp) = &SLIST_NEXT((var), field))

/*
 * Singly-linked List functions.
 */
#define	SLIST_INIT(head) {						\
	SLIST_FIRST(head) = SLIST_END(head);				\
}

#define	SLIST_INSERT_AFTER(slistelm, elm, field) do {			\
	(elm)->field.sle_next = (slistelm)->field.sle_next;		\
	(slistelm)->field.sle_next = (elm);				\
} while (0)

#define	SLIST_INSERT_HEAD(head, elm, field) do {			\
	(elm)->field.sle_next = (head)->slh_first;			\
	(head)->slh_first = (elm);					\
} while (0)

#define	SLIST_REMOVE_NEXT(head, elm, field) do {			\
	(elm)->field.sle_next = (elm)->field.sle_next->field.sle_next;	\
} while (0)

#define	SLIST_REMOVE_HEAD(head, field) do {				\
	(head)->slh_first = (head)->slh_first->field.sle_next;		\
} while (0)

#define SLIST_REMOVE(head, elm, type, field) do {			\
	if ((head)->slh_first == (elm)) {				\
		SLIST_REMOVE_HEAD((head), field);			\
	} else {							\
		struct type *curelm = (head)->slh_first;		\
									\
		while (curelm->field.sle_next != (elm))			\
			curelm = curelm->field.sle_next;		\
		curelm->field.sle_next =				\
		    curelm->field.sle_next->field.sle_next;		\
	}								\
} while (0)

/*
 * List definitions.
 */
#define LIST_HEAD(name, type)						\
struct name {								\
	struct type *lh_first;	/* first element */			\
}

#define LIST_HEAD_INITIALIZER(head)					\
	{ NULL }

#define LIST_ENTRY(type)						\
struct {								\
	struct type *le_next;	/* next element */			\
	struct type **le_prev;	/* address of previous next element */	\
}

/*
 * List access methods
 */
#define	LIST_FIRST(head)		((head)->lh_first)
#define	LIST_END(head)			NULL
#define	LIST_EMPTY(head)		(LIST_FIRST(head) == LIST_END(head))
#define	LIST_NEXT(elm, field)		((elm)->field.le_next)

#define LIST_FOREACH(var, head, field)					\
	for((var) = LIST_FIRST(head);					\
	    (var)!= LIST_END(head);					\
	    (var) = LIST_NEXT(var, field))

/*
 * List functions.
 */
#define	LIST_INIT(head) do {						\
	LIST_FIRST(head) = LIST_END(head);				\
} while (0)

#define LIST_INSERT_AFTER(listelm, elm, field) do {			\
	if (((elm)->field.le_next = (listelm)->field.le_next) != NULL)	\
		(listelm)->field.le_next->field.le_prev =		\
		    &(elm)->field.le_next;				\
	(listelm)->field.le_next = (elm);				\
	(elm)->field.le_prev = &(listelm)->field.le_next;		\
} while (0)

#define	LIST_INSERT_BEFORE(listelm, elm, field) do {			\
	(elm)->field.le_prev = (listelm)->field.le_prev;		\
	(elm)->field.le_next = (listelm);				\
	*(listelm)->field.le_prev = (elm);				\
	(listelm)->field.le_prev = &(elm)->field.le_next;		\
} while (0)

#define LIST_INSERT_HEAD(head, elm, field) do {				\
	if (((elm)->field.le_next = (head)->lh_first) != NULL)		\
		(head)->lh_first->field.le_prev = &(elm)->field.le_next;\
	(head)->lh_first = (elm);					\
	(elm)->field.le_prev = &(head)->lh_first;			\
} while (0)

#define LIST_REMOVE(elm, field) do {					\
	if ((elm)->field.le_next != NULL)				\
		(elm)->field.le_next->field.le_prev =			\
		    (elm)->field.le_prev;				\
	*(elm)->field.le_prev = (elm)->field.le_next;			\
} while (0)

#define LIST_REPLACE(elm, elm2, field) do {				\
	if (((elm2)->field.le_next = (elm)->field.le_next) != NULL)	\
		(elm2)->field.le_next->field.le_prev =			\
		    &(elm2)->field.le_next;				\
	(elm2)->field.le_prev = (elm)->field.le_prev;			\
	*(elm2)->field.le_prev = (elm2);				\
} while (0)

/*
 * Simple queue definitions.
 */
#define SIMPLEQ_HEAD(name, type)					\
struct name {								\
	struct type *sqh_first;	/* first element */			\
	struct type **sqh_last;	/* addr of last next element */		\
}

#define SIMPLEQ_HEAD_INITIALIZER(head)					\
	{ NULL, &(head).sqh_first }

#define SIMPLEQ_ENTRY(type)						\
struct {								\
	struct type *sqe_next;	/* next element */			\
}

/*
 * Simple queue access methods.
 */
#define	SIMPLEQ_FIRST(head)	    ((head)->sqh_first)
#define	SIMPLEQ_END(head)	    NULL
#define	SIMPLEQ_EMPTY(head)	    (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head))
#define	SIMPLEQ_NEXT(elm, field)    ((elm)->field.sqe_next)

#define SIMPLEQ_FOREACH(var, head, field)				\
	for((var) = SIMPLEQ_FIRST(head);				\
	    (var) != SIMPLEQ_END(head);					\
	    (var) = SIMPLEQ_NEXT(var, field))

/*
 * Simple queue functions.
 */
#define	SIMPLEQ_INIT(head) do {						\
	(head)->sqh_first = NULL;					\
	(head)->sqh_last = &(head)->sqh_first;				\
} while (0)

#define SIMPLEQ_INSERT_HEAD(head, elm, field) do {			\
	if (((elm)->field.sqe_next = (head)->sqh_first) == NULL)	\
		(head)->sqh_last = &(elm)->field.sqe_next;		\
	(head)->sqh_first = (elm);					\
} while (0)

#define SIMPLEQ_INSERT_TAIL(head, elm, field) do {			\
	(elm)->field.sqe_next = NULL;					\
	*(head)->sqh_last = (elm);					\
	(head)->sqh_last = &(elm)->field.sqe_next;			\
} while (0)

#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do {		\
	if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\
		(head)->sqh_last = &(elm)->field.sqe_next;		\
	(listelm)->field.sqe_next = (elm);				\
} while (0)

#define SIMPLEQ_REMOVE_HEAD(head, field) do {			\
	if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \
		(head)->sqh_last = &(head)->sqh_first;			\
} while (0)

/*
 * Tail queue definitions.
 */
#define TAILQ_HEAD(name, type)						\
struct name {								\
	struct type *tqh_first;	/* first element */			\
	struct type **tqh_last;	/* addr of last next element */		\
}

#define TAILQ_HEAD_INITIALIZER(head)					\
	{ NULL, &(head).tqh_first }

#define TAILQ_ENTRY(type)						\
struct {								\
	struct type *tqe_next;	/* next element */			\
	struct type **tqe_prev;	/* address of previous next element */	\
}

/* 
 * tail queue access methods 
 */
#define	TAILQ_FIRST(head)		((head)->tqh_first)
#define	TAILQ_END(head)			NULL
#define	TAILQ_NEXT(elm, field)		((elm)->field.tqe_next)
#define TAILQ_LAST(head, headname)					\
	(*(((struct headname *)((head)->tqh_last))->tqh_last))
/* XXX */
#define TAILQ_PREV(elm, headname, field)				\
	(*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
#define	TAILQ_EMPTY(head)						\
	(TAILQ_FIRST(head) == TAILQ_END(head))

#define TAILQ_FOREACH(var, head, field)					\
	for((var) = TAILQ_FIRST(head);					\
	    (var) != TAILQ_END(head);					\
	    (var) = TAILQ_NEXT(var, field))

#define TAILQ_FOREACH_REVERSE(var, head, headname, field)		\
	for((var) = TAILQ_LAST(head, headname);				\
	    (var) != TAILQ_END(head);					\
	    (var) = TAILQ_PREV(var, headname, field))

/*
 * Tail queue functions.
 */
#define	TAILQ_INIT(head) do {						\
	(head)->tqh_first = NULL;					\
	(head)->tqh_last = &(head)->tqh_first;				\
} while (0)

#define TAILQ_INSERT_HEAD(head, elm, field) do {			\
	if (((elm)->field.tqe_next = (head)->tqh_first) != NULL)	\
		(head)->tqh_first->field.tqe_prev =			\
		    &(elm)->field.tqe_next;				\
	else								\
		(head)->tqh_last = &(elm)->field.tqe_next;		\
	(head)->tqh_first = (elm);					\
	(elm)->field.tqe_prev = &(head)->tqh_first;			\
} while (0)

#define TAILQ_INSERT_TAIL(head, elm, field) do {			\
	(elm)->field.tqe_next = NULL;					\
	(elm)->field.tqe_prev = (head)->tqh_last;			\
	*(head)->tqh_last = (elm);					\
	(head)->tqh_last = &(elm)->field.tqe_next;			\
} while (0)

#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do {		\
	if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
		(elm)->field.tqe_next->field.tqe_prev =			\
		    &(elm)->field.tqe_next;				\
	else								\
		(head)->tqh_last = &(elm)->field.tqe_next;		\
	(listelm)->field.tqe_next = (elm);				\
	(elm)->field.tqe_prev = &(listelm)->field.tqe_next;		\
} while (0)

#define	TAILQ_INSERT_BEFORE(listelm, elm, field) do {			\
	(elm)->field.tqe_prev = (listelm)->field.tqe_prev;		\
	(elm)->field.tqe_next = (listelm);				\
	*(listelm)->field.tqe_prev = (elm);				\
	(listelm)->field.tqe_prev = &(elm)->field.tqe_next;		\
} while (0)

#define TAILQ_REMOVE(head, elm, field) do {				\
	if (((elm)->field.tqe_next) != NULL)				\
		(elm)->field.tqe_next->field.tqe_prev =			\
		    (elm)->field.tqe_prev;				\
	else								\
		(head)->tqh_last = (elm)->field.tqe_prev;		\
	*(elm)->field.tqe_prev = (elm)->field.tqe_next;			\
} while (0)

#define TAILQ_REPLACE(head, elm, elm2, field) do {			\
	if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL)	\
		(elm2)->field.tqe_next->field.tqe_prev =		\
		    &(elm2)->field.tqe_next;				\
	else								\
		(head)->tqh_last = &(elm2)->field.tqe_next;		\
	(elm2)->field.tqe_prev = (elm)->field.tqe_prev;			\
	*(elm2)->field.tqe_prev = (elm2);				\
} while (0)

/*
 * Circular queue definitions.
 */
#define CIRCLEQ_HEAD(name, type)					\
struct name {								\
	struct type *cqh_first;		/* first element */		\
	struct type *cqh_last;		/* last element */		\
}

#define CIRCLEQ_HEAD_INITIALIZER(head)					\
	{ CIRCLEQ_END(&head), CIRCLEQ_END(&head) }

#define CIRCLEQ_ENTRY(type)						\
struct {								\
	struct type *cqe_next;		/* next element */		\
	struct type *cqe_prev;		/* previous element */		\
}

/*
 * Circular queue access methods 
 */
#define	CIRCLEQ_FIRST(head)		((head)->cqh_first)
#define	CIRCLEQ_LAST(head)		((head)->cqh_last)
#define	CIRCLEQ_END(head)		((void *)(head))
#define	CIRCLEQ_NEXT(elm, field)	((elm)->field.cqe_next)
#define	CIRCLEQ_PREV(elm, field)	((elm)->field.cqe_prev)
#define	CIRCLEQ_EMPTY(head)						\
	(CIRCLEQ_FIRST(head) == CIRCLEQ_END(head))

#define CIRCLEQ_FOREACH(var, head, field)				\
	for((var) = CIRCLEQ_FIRST(head);				\
	    (var) != CIRCLEQ_END(head);					\
	    (var) = CIRCLEQ_NEXT(var, field))

#define CIRCLEQ_FOREACH_REVERSE(var, head, field)			\
	for((var) = CIRCLEQ_LAST(head);					\
	    (var) != CIRCLEQ_END(head);					\
	    (var) = CIRCLEQ_PREV(var, field))

/*
 * Circular queue functions.
 */
#define	CIRCLEQ_INIT(head) do {						\
	(head)->cqh_first = CIRCLEQ_END(head);				\
	(head)->cqh_last = CIRCLEQ_END(head);				\
} while (0)

#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do {		\
	(elm)->field.cqe_next = (listelm)->field.cqe_next;		\
	(elm)->field.cqe_prev = (listelm);				\
	if ((listelm)->field.cqe_next == CIRCLEQ_END(head))		\
		(head)->cqh_last = (elm);				\
	else								\
		(listelm)->field.cqe_next->field.cqe_prev = (elm);	\
	(listelm)->field.cqe_next = (elm);				\
} while (0)

#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do {		\
	(elm)->field.cqe_next = (listelm);				\
	(elm)->field.cqe_prev = (listelm)->field.cqe_prev;		\
	if ((listelm)->field.cqe_prev == CIRCLEQ_END(head))		\
		(head)->cqh_first = (elm);				\
	else								\
		(listelm)->field.cqe_prev->field.cqe_next = (elm);	\
	(listelm)->field.cqe_prev = (elm);				\
} while (0)

#define CIRCLEQ_INSERT_HEAD(head, elm, field) do {			\
	(elm)->field.cqe_next = (head)->cqh_first;			\
	(elm)->field.cqe_prev = CIRCLEQ_END(head);			\
	if ((head)->cqh_last == CIRCLEQ_END(head))			\
		(head)->cqh_last = (elm);				\
	else								\
		(head)->cqh_first->field.cqe_prev = (elm);		\
	(head)->cqh_first = (elm);					\
} while (0)

#define CIRCLEQ_INSERT_TAIL(head, elm, field) do {			\
	(elm)->field.cqe_next = CIRCLEQ_END(head);			\
	(elm)->field.cqe_prev = (head)->cqh_last;			\
	if ((head)->cqh_first == CIRCLEQ_END(head))			\
		(head)->cqh_first = (elm);				\
	else								\
		(head)->cqh_last->field.cqe_next = (elm);		\
	(head)->cqh_last = (elm);					\
} while (0)

#define	CIRCLEQ_REMOVE(head, elm, field) do {				\
	if ((elm)->field.cqe_next == CIRCLEQ_END(head))			\
		(head)->cqh_last = (elm)->field.cqe_prev;		\
	else								\
		(elm)->field.cqe_next->field.cqe_prev =			\
		    (elm)->field.cqe_prev;				\
	if ((elm)->field.cqe_prev == CIRCLEQ_END(head))			\
		(head)->cqh_first = (elm)->field.cqe_next;		\
	else								\
		(elm)->field.cqe_prev->field.cqe_next =			\
		    (elm)->field.cqe_next;				\
} while (0)

#define CIRCLEQ_REPLACE(head, elm, elm2, field) do {			\
	if (((elm2)->field.cqe_next = (elm)->field.cqe_next) ==		\
	    CIRCLEQ_END(head))						\
		(head).cqh_last = (elm2);				\
	else								\
		(elm2)->field.cqe_next->field.cqe_prev = (elm2);	\
	if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) ==		\
	    CIRCLEQ_END(head))						\
		(head).cqh_first = (elm2);				\
	else								\
		(elm2)->field.cqe_prev->field.cqe_next = (elm2);	\
} while (0)

#endif	/* !_FAKE_QUEUE_H_ */
Commit	Line	Data
d0f02ff0	1	/* $OpenBSD: queue.h,v 1.27 2005/02/25 13:29:30 deraadt Exp $ */
bf5f69f7	2	/* $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ */
	3
	4	/*
	5	* Copyright (c) 1991, 1993
	6	* The Regents of the University of California. All rights reserved.
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	11	* 1. Redistributions of source code must retain the above copyright
	12	* notice, this list of conditions and the following disclaimer.
	13	* 2. Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in the
	15	* documentation and/or other materials provided with the distribution.
3e67f7df	16	* 3. Neither the name of the University nor the names of its contributors
bf5f69f7	17	* may be used to endorse or promote products derived from this software
	18	* without specific prior written permission.
	19	*
	20	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	* SUCH DAMAGE.
	31	*
	32	* @(#)queue.h 8.5 (Berkeley) 8/20/94
	33	*/
	34
f6d4fb87	35	/* OPENBSD ORIGINAL: sys/sys/queue.h */
f6d4fb87	36
a205f92a	37	#ifndef _FAKE_QUEUE_H_
	38	#define _FAKE_QUEUE_H_
	39
	40	/*
	41	* Require for OS/X and other platforms that have old/broken/incomplete
	42	* <sys/queue.h>.
	43	*/
	44	#undef SLIST_HEAD
	45	#undef SLIST_HEAD_INITIALIZER
	46	#undef SLIST_ENTRY
	47	#undef SLIST_FOREACH_PREVPTR
	48	#undef SLIST_FIRST
	49	#undef SLIST_END
	50	#undef SLIST_EMPTY
	51	#undef SLIST_NEXT
	52	#undef SLIST_FOREACH
	53	#undef SLIST_INIT
	54	#undef SLIST_INSERT_AFTER
	55	#undef SLIST_INSERT_HEAD
	56	#undef SLIST_REMOVE_HEAD
	57	#undef SLIST_REMOVE
	58	#undef SLIST_REMOVE_NEXT
	59	#undef LIST_HEAD
	60	#undef LIST_HEAD_INITIALIZER
	61	#undef LIST_ENTRY
	62	#undef LIST_FIRST
	63	#undef LIST_END
	64	#undef LIST_EMPTY
	65	#undef LIST_NEXT
	66	#undef LIST_FOREACH
	67	#undef LIST_INIT
	68	#undef LIST_INSERT_AFTER
	69	#undef LIST_INSERT_BEFORE
	70	#undef LIST_INSERT_HEAD
	71	#undef LIST_REMOVE
	72	#undef LIST_REPLACE
	73	#undef SIMPLEQ_HEAD
	74	#undef SIMPLEQ_HEAD_INITIALIZER
	75	#undef SIMPLEQ_ENTRY
	76	#undef SIMPLEQ_FIRST
	77	#undef SIMPLEQ_END
	78	#undef SIMPLEQ_EMPTY
	79	#undef SIMPLEQ_NEXT
	80	#undef SIMPLEQ_FOREACH
	81	#undef SIMPLEQ_INIT
	82	#undef SIMPLEQ_INSERT_HEAD
	83	#undef SIMPLEQ_INSERT_TAIL
	84	#undef SIMPLEQ_INSERT_AFTER
	85	#undef SIMPLEQ_REMOVE_HEAD
	86	#undef TAILQ_HEAD
	87	#undef TAILQ_HEAD_INITIALIZER
	88	#undef TAILQ_ENTRY
	89	#undef TAILQ_FIRST
	90	#undef TAILQ_END
	91	#undef TAILQ_NEXT
	92	#undef TAILQ_LAST
	93	#undef TAILQ_PREV
	94	#undef TAILQ_EMPTY
	95	#undef TAILQ_FOREACH
	96	#undef TAILQ_FOREACH_REVERSE
	97	#undef TAILQ_INIT
	98	#undef TAILQ_INSERT_HEAD
	99	#undef TAILQ_INSERT_TAIL
	100	#undef TAILQ_INSERT_AFTER
101	#undef TAILQ_INSERT_BEFORE
102	#undef TAILQ_REMOVE
103	#undef TAILQ_REPLACE
104	#undef CIRCLEQ_HEAD
105	#undef CIRCLEQ_HEAD_INITIALIZER
106	#undef CIRCLEQ_ENTRY
107	#undef CIRCLEQ_FIRST
108	#undef CIRCLEQ_LAST
109	#undef CIRCLEQ_END
110	#undef CIRCLEQ_NEXT
111	#undef CIRCLEQ_PREV
112	#undef CIRCLEQ_EMPTY
113	#undef CIRCLEQ_FOREACH
114	#undef CIRCLEQ_FOREACH_REVERSE
115	#undef CIRCLEQ_INIT
116	#undef CIRCLEQ_INSERT_AFTER
117	#undef CIRCLEQ_INSERT_BEFORE
118	#undef CIRCLEQ_INSERT_HEAD
119	#undef CIRCLEQ_INSERT_TAIL
120	#undef CIRCLEQ_REMOVE
121	#undef CIRCLEQ_REPLACE
bf5f69f7	122
	123	/*
	124	* This file defines five types of data structures: singly-linked lists,
	125	* lists, simple queues, tail queues, and circular queues.
	126	*
	127	*
	128	* A singly-linked list is headed by a single forward pointer. The elements
	129	* are singly linked for minimum space and pointer manipulation overhead at
	130	* the expense of O(n) removal for arbitrary elements. New elements can be
	131	* added to the list after an existing element or at the head of the list.
	132	* Elements being removed from the head of the list should use the explicit
	133	* macro for this purpose for optimum efficiency. A singly-linked list may
	134	* only be traversed in the forward direction. Singly-linked lists are ideal
	135	* for applications with large datasets and few or no removals or for
	136	* implementing a LIFO queue.
	137	*
	138	* A list is headed by a single forward pointer (or an array of forward
	139	* pointers for a hash table header). The elements are doubly linked
	140	* so that an arbitrary element can be removed without a need to
	141	* traverse the list. New elements can be added to the list before
	142	* or after an existing element or at the head of the list. A list
	143	* may only be traversed in the forward direction.
	144	*
	145	* A simple queue is headed by a pair of pointers, one the head of the
	146	* list and the other to the tail of the list. The elements are singly
	147	* linked to save space, so elements can only be removed from the
	148	* head of the list. New elements can be added to the list before or after
	149	* an existing element, at the head of the list, or at the end of the
	150	* list. A simple queue may only be traversed in the forward direction.
	151	*
	152	* A tail queue is headed by a pair of pointers, one to the head of the
	153	* list and the other to the tail of the list. The elements are doubly
	154	* linked so that an arbitrary element can be removed without a need to
	155	* traverse the list. New elements can be added to the list before or
	156	* after an existing element, at the head of the list, or at the end of
	157	* the list. A tail queue may be traversed in either direction.
	158	*
	159	* A circle queue is headed by a pair of pointers, one to the head of the
	160	* list and the other to the tail of the list. The elements are doubly
	161	* linked so that an arbitrary element can be removed without a need to
	162	* traverse the list. New elements can be added to the list before or after
	163	* an existing element, at the head of the list, or at the end of the list.
	164	* A circle queue may be traversed in either direction, but has a more
	165	* complex end of list detection.
	166	*
	167	* For details on the use of these macros, see the queue(3) manual page.
	168	*/
	169
	170	/*
	171	* Singly-linked List definitions.
	172	*/
	173	#define SLIST_HEAD(name, type) \
	174	struct name { \
	175	struct type slh_first; / first element */ \
	176	}
	177
	178	#define SLIST_HEAD_INITIALIZER(head) \
	179	{ NULL }
	180
	181	#define SLIST_ENTRY(type) \
	182	struct { \
	183	struct type sle_next; / next element */ \
	184	}
	185
186	/*
187	* Singly-linked List access methods.
188	*/
189	#define SLIST_FIRST(head) ((head)->slh_first)
190	#define SLIST_END(head) NULL
191	#define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head))
192	#define SLIST_NEXT(elm, field) ((elm)->field.sle_next)
193
194	#define SLIST_FOREACH(var, head, field) \
195	for((var) = SLIST_FIRST(head); \
196	(var) != SLIST_END(head); \
197	(var) = SLIST_NEXT(var, field))
198
22ca4f57	199	#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \
	200	for ((varp) = &SLIST_FIRST((head)); \
	201	((var) = *(varp)) != SLIST_END(head); \
	202	(varp) = &SLIST_NEXT((var), field))
	203
bf5f69f7	204	/*
	205	* Singly-linked List functions.
	206	*/
	207	#define SLIST_INIT(head) { \
	208	SLIST_FIRST(head) = SLIST_END(head); \
	209	}
	210
	211	#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \
	212	(elm)->field.sle_next = (slistelm)->field.sle_next; \
	213	(slistelm)->field.sle_next = (elm); \
	214	} while (0)
	215
	216	#define SLIST_INSERT_HEAD(head, elm, field) do { \
	217	(elm)->field.sle_next = (head)->slh_first; \
	218	(head)->slh_first = (elm); \
	219	} while (0)
	220
22ca4f57	221	#define SLIST_REMOVE_NEXT(head, elm, field) do { \
	222	(elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \
	223	} while (0)
	224
bf5f69f7	225	#define SLIST_REMOVE_HEAD(head, field) do { \
	226	(head)->slh_first = (head)->slh_first->field.sle_next; \
	227	} while (0)
	228
1656cbed	229	#define SLIST_REMOVE(head, elm, type, field) do { \
	230	if ((head)->slh_first == (elm)) { \
	231	SLIST_REMOVE_HEAD((head), field); \
d0f02ff0	232	} else { \
1656cbed	233	struct type *curelm = (head)->slh_first; \
d0f02ff0	234	\
d0f02ff0	235	while (curelm->field.sle_next != (elm)) \
1656cbed	236	curelm = curelm->field.sle_next; \
	237	curelm->field.sle_next = \
	238	curelm->field.sle_next->field.sle_next; \
	239	} \
	240	} while (0)
	241
bf5f69f7	242	/*
	243	* List definitions.
	244	*/
	245	#define LIST_HEAD(name, type) \
	246	struct name { \
	247	struct type lh_first; / first element */ \
	248	}
	249
	250	#define LIST_HEAD_INITIALIZER(head) \
	251	{ NULL }
	252
	253	#define LIST_ENTRY(type) \
	254	struct { \
	255	struct type le_next; / next element */ \
	256	struct type *le_prev; / address of previous next element */ \
	257	}
	258
	259	/*
	260	* List access methods
	261	*/
	262	#define LIST_FIRST(head) ((head)->lh_first)
	263	#define LIST_END(head) NULL
	264	#define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head))
	265	#define LIST_NEXT(elm, field) ((elm)->field.le_next)
	266
	267	#define LIST_FOREACH(var, head, field) \
	268	for((var) = LIST_FIRST(head); \
	269	(var)!= LIST_END(head); \
	270	(var) = LIST_NEXT(var, field))
	271
	272	/*
	273	* List functions.
	274	*/
	275	#define LIST_INIT(head) do { \
	276	LIST_FIRST(head) = LIST_END(head); \
	277	} while (0)
	278
	279	#define LIST_INSERT_AFTER(listelm, elm, field) do { \
	280	if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \
	281	(listelm)->field.le_next->field.le_prev = \
	282	&(elm)->field.le_next; \
	283	(listelm)->field.le_next = (elm); \
	284	(elm)->field.le_prev = &(listelm)->field.le_next; \
	285	} while (0)
	286
	287	#define LIST_INSERT_BEFORE(listelm, elm, field) do { \
	288	(elm)->field.le_prev = (listelm)->field.le_prev; \
	289	(elm)->field.le_next = (listelm); \
	290	*(listelm)->field.le_prev = (elm); \
	291	(listelm)->field.le_prev = &(elm)->field.le_next; \
	292	} while (0)
	293
	294	#define LIST_INSERT_HEAD(head, elm, field) do { \
	295	if (((elm)->field.le_next = (head)->lh_first) != NULL) \
	296	(head)->lh_first->field.le_prev = &(elm)->field.le_next;\
	297	(head)->lh_first = (elm); \
	298	(elm)->field.le_prev = &(head)->lh_first; \
	299	} while (0)
	300
	301	#define LIST_REMOVE(elm, field) do { \
	302	if ((elm)->field.le_next != NULL) \
	303	(elm)->field.le_next->field.le_prev = \
	304	(elm)->field.le_prev; \
	305	*(elm)->field.le_prev = (elm)->field.le_next; \
306	} while (0)
307
308	#define LIST_REPLACE(elm, elm2, field) do { \
309	if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \
310	(elm2)->field.le_next->field.le_prev = \
311	&(elm2)->field.le_next; \
312	(elm2)->field.le_prev = (elm)->field.le_prev; \
313	*(elm2)->field.le_prev = (elm2); \
314	} while (0)
315
316	/*
317	* Simple queue definitions.
318	*/
319	#define SIMPLEQ_HEAD(name, type) \
320	struct name { \
321	struct type sqh_first; / first element */ \
322	struct type *sqh_last; / addr of last next element */ \
323	}
324
325	#define SIMPLEQ_HEAD_INITIALIZER(head) \
326	{ NULL, &(head).sqh_first }
327
328	#define SIMPLEQ_ENTRY(type) \
329	struct { \
330	struct type sqe_next; / next element */ \
331	}
332
333	/*
334	* Simple queue access methods.
335	*/
336	#define SIMPLEQ_FIRST(head) ((head)->sqh_first)
337	#define SIMPLEQ_END(head) NULL
338	#define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head))
339	#define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next)
340
341	#define SIMPLEQ_FOREACH(var, head, field) \
342	for((var) = SIMPLEQ_FIRST(head); \
343	(var) != SIMPLEQ_END(head); \
344	(var) = SIMPLEQ_NEXT(var, field))
345
346	/*
347	* Simple queue functions.
348	*/
349	#define SIMPLEQ_INIT(head) do { \
350	(head)->sqh_first = NULL; \
351	(head)->sqh_last = &(head)->sqh_first; \
352	} while (0)
353
354	#define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \
355	if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \
356	(head)->sqh_last = &(elm)->field.sqe_next; \
357	(head)->sqh_first = (elm); \
358	} while (0)
359
360	#define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \
361	(elm)->field.sqe_next = NULL; \
362	*(head)->sqh_last = (elm); \
363	(head)->sqh_last = &(elm)->field.sqe_next; \
364	} while (0)
365
366	#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
367	if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\
368	(head)->sqh_last = &(elm)->field.sqe_next; \
369	(listelm)->field.sqe_next = (elm); \
370	} while (0)
371
e271997a	372	#define SIMPLEQ_REMOVE_HEAD(head, field) do { \
e271997a	373	if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \
bf5f69f7	374	(head)->sqh_last = &(head)->sqh_first; \
	375	} while (0)
	376
	377	/*
	378	* Tail queue definitions.
	379	*/
	380	#define TAILQ_HEAD(name, type) \
	381	struct name { \
	382	struct type tqh_first; / first element */ \
	383	struct type *tqh_last; / addr of last next element */ \
	384	}
	385
	386	#define TAILQ_HEAD_INITIALIZER(head) \
	387	{ NULL, &(head).tqh_first }
	388
	389	#define TAILQ_ENTRY(type) \
	390	struct { \
	391	struct type tqe_next; / next element */ \
	392	struct type *tqe_prev; / address of previous next element */ \
	393	}
	394
	395	/*
	396	* tail queue access methods
	397	*/
	398	#define TAILQ_FIRST(head) ((head)->tqh_first)
	399	#define TAILQ_END(head) NULL
	400	#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
	401	#define TAILQ_LAST(head, headname) \
	402	((((struct headname )((head)->tqh_last))->tqh_last))
	403	/* XXX */
	404	#define TAILQ_PREV(elm, headname, field) \
	405	((((struct headname )((elm)->field.tqe_prev))->tqh_last))
	406	#define TAILQ_EMPTY(head) \
	407	(TAILQ_FIRST(head) == TAILQ_END(head))
	408
	409	#define TAILQ_FOREACH(var, head, field) \
	410	for((var) = TAILQ_FIRST(head); \
	411	(var) != TAILQ_END(head); \
	412	(var) = TAILQ_NEXT(var, field))
	413
22ca4f57	414	#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \
bf5f69f7	415	for((var) = TAILQ_LAST(head, headname); \
	416	(var) != TAILQ_END(head); \
	417	(var) = TAILQ_PREV(var, headname, field))
	418
	419	/*
	420	* Tail queue functions.
	421	*/
	422	#define TAILQ_INIT(head) do { \
	423	(head)->tqh_first = NULL; \
	424	(head)->tqh_last = &(head)->tqh_first; \
	425	} while (0)
	426
	427	#define TAILQ_INSERT_HEAD(head, elm, field) do { \
	428	if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \
	429	(head)->tqh_first->field.tqe_prev = \
	430	&(elm)->field.tqe_next; \
	431	else \
	432	(head)->tqh_last = &(elm)->field.tqe_next; \
	433	(head)->tqh_first = (elm); \
	434	(elm)->field.tqe_prev = &(head)->tqh_first; \
	435	} while (0)
	436
	437	#define TAILQ_INSERT_TAIL(head, elm, field) do { \
	438	(elm)->field.tqe_next = NULL; \
	439	(elm)->field.tqe_prev = (head)->tqh_last; \
	440	*(head)->tqh_last = (elm); \
	441	(head)->tqh_last = &(elm)->field.tqe_next; \
	442	} while (0)
	443
	444	#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
	445	if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
	446	(elm)->field.tqe_next->field.tqe_prev = \
	447	&(elm)->field.tqe_next; \
	448	else \
	449	(head)->tqh_last = &(elm)->field.tqe_next; \
	450	(listelm)->field.tqe_next = (elm); \
	451	(elm)->field.tqe_prev = &(listelm)->field.tqe_next; \
	452	} while (0)
	453
	454	#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \
	455	(elm)->field.tqe_prev = (listelm)->field.tqe_prev; \
	456	(elm)->field.tqe_next = (listelm); \
	457	*(listelm)->field.tqe_prev = (elm); \
	458	(listelm)->field.tqe_prev = &(elm)->field.tqe_next; \
	459	} while (0)
	460
	461	#define TAILQ_REMOVE(head, elm, field) do { \
	462	if (((elm)->field.tqe_next) != NULL) \
	463	(elm)->field.tqe_next->field.tqe_prev = \
	464	(elm)->field.tqe_prev; \
	465	else \
	466	(head)->tqh_last = (elm)->field.tqe_prev; \
	467	*(elm)->field.tqe_prev = (elm)->field.tqe_next; \
	468	} while (0)
	469
	470	#define TAILQ_REPLACE(head, elm, elm2, field) do { \
	471	if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \
	472	(elm2)->field.tqe_next->field.tqe_prev = \
	473	&(elm2)->field.tqe_next; \
	474	else \
	475	(head)->tqh_last = &(elm2)->field.tqe_next; \
	476	(elm2)->field.tqe_prev = (elm)->field.tqe_prev; \
	477	*(elm2)->field.tqe_prev = (elm2); \
	478	} while (0)
479
480	/*
481	* Circular queue definitions.
482	*/
483	#define CIRCLEQ_HEAD(name, type) \
484	struct name { \
485	struct type cqh_first; / first element */ \
486	struct type cqh_last; / last element */ \
487	}
488
489	#define CIRCLEQ_HEAD_INITIALIZER(head) \
490	{ CIRCLEQ_END(&head), CIRCLEQ_END(&head) }
491
492	#define CIRCLEQ_ENTRY(type) \
493	struct { \
494	struct type cqe_next; / next element */ \
495	struct type cqe_prev; / previous element */ \
496	}
497
498	/*
499	* Circular queue access methods
500	*/
501	#define CIRCLEQ_FIRST(head) ((head)->cqh_first)
502	#define CIRCLEQ_LAST(head) ((head)->cqh_last)
503	#define CIRCLEQ_END(head) ((void *)(head))
504	#define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next)
505	#define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev)
506	#define CIRCLEQ_EMPTY(head) \
507	(CIRCLEQ_FIRST(head) == CIRCLEQ_END(head))
508
509	#define CIRCLEQ_FOREACH(var, head, field) \
510	for((var) = CIRCLEQ_FIRST(head); \
511	(var) != CIRCLEQ_END(head); \
512	(var) = CIRCLEQ_NEXT(var, field))
513
514	#define CIRCLEQ_FOREACH_REVERSE(var, head, field) \
515	for((var) = CIRCLEQ_LAST(head); \
516	(var) != CIRCLEQ_END(head); \
517	(var) = CIRCLEQ_PREV(var, field))
518
519	/*
520	* Circular queue functions.
521	*/
522	#define CIRCLEQ_INIT(head) do { \
523	(head)->cqh_first = CIRCLEQ_END(head); \
524	(head)->cqh_last = CIRCLEQ_END(head); \
525	} while (0)
526
527	#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
528	(elm)->field.cqe_next = (listelm)->field.cqe_next; \
529	(elm)->field.cqe_prev = (listelm); \
530	if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \
531	(head)->cqh_last = (elm); \
532	else \
533	(listelm)->field.cqe_next->field.cqe_prev = (elm); \
534	(listelm)->field.cqe_next = (elm); \
535	} while (0)
536
537	#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \
538	(elm)->field.cqe_next = (listelm); \
539	(elm)->field.cqe_prev = (listelm)->field.cqe_prev; \
540	if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \
541	(head)->cqh_first = (elm); \
542	else \
543	(listelm)->field.cqe_prev->field.cqe_next = (elm); \
544	(listelm)->field.cqe_prev = (elm); \
545	} while (0)
546
547	#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \
548	(elm)->field.cqe_next = (head)->cqh_first; \
549	(elm)->field.cqe_prev = CIRCLEQ_END(head); \
550	if ((head)->cqh_last == CIRCLEQ_END(head)) \
551	(head)->cqh_last = (elm); \
552	else \
553	(head)->cqh_first->field.cqe_prev = (elm); \
554	(head)->cqh_first = (elm); \
555	} while (0)
556
557	#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \
558	(elm)->field.cqe_next = CIRCLEQ_END(head); \
559	(elm)->field.cqe_prev = (head)->cqh_last; \
560	if ((head)->cqh_first == CIRCLEQ_END(head)) \
561	(head)->cqh_first = (elm); \
562	else \
563	(head)->cqh_last->field.cqe_next = (elm); \
564	(head)->cqh_last = (elm); \
565	} while (0)
566
567	#define CIRCLEQ_REMOVE(head, elm, field) do { \
568	if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \
569	(head)->cqh_last = (elm)->field.cqe_prev; \
570	else \
571	(elm)->field.cqe_next->field.cqe_prev = \
572	(elm)->field.cqe_prev; \
573	if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \
574	(head)->cqh_first = (elm)->field.cqe_next; \
575	else \
576	(elm)->field.cqe_prev->field.cqe_next = \
577	(elm)->field.cqe_next; \
578	} while (0)
579
580	#define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \
581	if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \
582	CIRCLEQ_END(head)) \
583	(head).cqh_last = (elm2); \
584	else \
585	(elm2)->field.cqe_next->field.cqe_prev = (elm2); \
586	if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \
587	CIRCLEQ_END(head)) \
588	(head).cqh_first = (elm2); \
589	else \
590	(elm2)->field.cqe_prev->field.cqe_next = (elm2); \
591	} while (0)
592
a205f92a	593	#endif /* !_FAKE_QUEUE_H_ */