/* dlist.h - doubly linked list header file */

/*
 * Copyright (c) 2013-2014 Wind River Systems, Inc.
 *
 * 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 Wind River Systems 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
 */

/*
DESCRIPTION
This header file implements the necessary structure definitions for a doubly
linked list.
*/

#ifndef _DLIST_H
#define _DLIST_H

/* typedefs */

typedef struct dnode_s {
	union {
		struct dnode_s *head; /* ptr to head of list (dlist_t) */
		struct dnode_s *next; /* ptr to next node    (dnode_t) */
	};
	union {
		struct dnode_s *tail; /* ptr to tail of list (dlist_t) */
		struct dnode_s *prev; /* ptr to previous node (dnode_t) */
	};
} dlist_t, dnode_t;

/* externs */

extern void dlistAdd(dlist_t *pList, dnode_t *pNode);
extern void dlistRemove(dnode_t *pNode);
extern dnode_t *dlistGet(dlist_t *pList);

#endif /* _DLIST_H */