/*	$NetBSD: _que.c,v 1.3 2005/12/11 12:24:37 christos Exp $	*/

/*-
 * Copyright (c) 2001 The NetBSD Foundation, Inc.
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the NetBSD
 *	Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

/*
 * Use <sys/queue.h> macros for new code, queue functions provided here
 * are obsolete. Once the remaining code using this would be converted
 * to use <sys/queue.h>, this would be removed.
 */

#include <sys/types.h>
#include <sys/systm.h>

struct queue {
	struct queue *q_next, *q_prev;
};

/*
 * insert an element into a queue
 */

void
_insque(v1, v2)
	void *v1;
	void *v2;
{
	struct queue *elem = v1, *head = v2;
	struct queue *next;

	next = head->q_next;
	elem->q_next = next;
	head->q_next = elem;
	elem->q_prev = head;
	next->q_prev = elem;
}

/*
 * remove an element from a queue
 */

void
_remque(v)
	void *v;
{
	struct queue *elem = v;
	struct queue *next, *prev;

	next = elem->q_next;
	prev = elem->q_prev;
	next->q_prev = prev;
	prev->q_next = next;
	elem->q_prev = 0;
}