/**************************************************************************/
/*									  */
/* Copyright (c) 2000-2005 by Alexandr V. Shutko, Khabarovsk, Russia	  */
/* 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.							  */
/*                                                                        */
/* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.			  */
/*                                                                        */
/* $Id: dlinklist.h,v 1.6 2005/01/05 05:51:46 regress Exp $		  */
/**************************************************************************/

#define DLIST_ADD(list, p) \
{ \
        if (!(list)) { \
		(list) = (p); \
		(p)->next = (p)->prev = NULL; \
	} else { \
		(list)->prev = (p); \
		(p)->next = (list); \
		(p)->prev = NULL; \
		(list) = (p); \
	}\
}


/* remove an element from a list */
#define DLIST_REMOVE(list, p) \
{ \
	if ((p) == (list)) { \
		(list) = (p)->next; \
		if (list) (list)->prev = NULL; \
	} else { \
		(p)->prev->next = (p)->next; \
		if ((p)->next) (p)->next->prev = (p)->prev; \
	} \
}

/* promote an element to the top of the list */
#define DLIST_PROMOTE(list, p) \
          DLIST_REMOVE(list, p) \
          DLIST_ADD(list, p)