cache-node.c

/*
 * $Id: cache-node.c,v 0.22 2001/11/05 23:52:11 ceder Exp $
 * Copyright (C) 1991, 1993-1994, 1996, 1998-1999  Lysator Academic Computer Association.
 *
 * This file is part of the LysKOM server.
 * 
 * LysKOM is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by 
 * the Free Software Foundation; either version 1, or (at your option) 
 * any later version.
 * 
 * LysKOM is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with LysKOM; see the file COPYING.  If not, write to
 * Lysator, c/o ISY, Linkoping University, S-581 83 Linkoping, SWEDEN,
 * or the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, 
 * MA 02139, USA.
 *
 * Please mail bug reports to bug-lyskom@lysator.liu.se. 
 */
/*
 * cache-node.c
 *
 * Used in diskomd.
 */


#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include <sys/types.h>
#include <stdio.h>
#ifdef HAVE_STDDEF_H
#  include <stddef.h>
#endif

#include "cache-node.h"
#include "exp.h"
#include "server/smalloc.h"
#include "lyskomd.h"

EXPORT const Cache_node EMPTY_CACHE_NODE =
    {{ 0, 0 }, NULL, NULL, 0, 0, 0, 0, NULL, NULL, 0};

EXPORT const Cache_node_block EMPTY_CACHE_NODE_BLOCK =
    { 0, NULL, NULL};

EXPORT const Cache_node_mcb EMPTY_CACHE_NODE_MCB =
    { 0, NULL, 0, 0, NULL, NULL, 0, NULL };


EXPORT  void
unlink_lru(Cache_node *node,
	   Cache_node **lru,
	   Cache_node **mru)
{
    Cache_node *link;
    
    link = node->next;

    if ( node->next != NULL )
	node->next->prev = node->prev;
    else if (*lru == node)
	*lru = node->prev;