/* -*- Mode: C; tab-width: 4 -*-
 *
 * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef __GenLinkedList__
#define __GenLinkedList__


#include <stddef.h>


struct	GenLinkedList
{
	void		*Head,
				*Tail;
	size_t		LinkOffset;
};
typedef struct GenLinkedList	GenLinkedList;


void		InitLinkedList( GenLinkedList *pList, size_t linkOffset);

void		AddToHead( GenLinkedList *pList, void *elem);
void		AddToTail( GenLinkedList *pList, void *elem);

int		RemoveFromList( GenLinkedList *pList, void *elem);

int		ReplaceElem( GenLinkedList *pList, void *elemInList, void *newElem);


struct	GenDoubleLinkedList
{
	void		*Head,
				*Tail;
	size_t		FwdLinkOffset,
				BackLinkOffset;
};
typedef struct GenDoubleLinkedList	GenDoubleLinkedList;


void		InitDoubleLinkedList( GenDoubleLinkedList *pList, size_t fwdLinkOffset,
									  size_t backLinkOffset);

void		DLLAddToHead( GenDoubleLinkedList *pList, void *elem);

void		DLLRemoveFromList( GenDoubleLinkedList *pList, void *elem);


/* A GenLinkedOffsetList is like a GenLinkedList that stores the *Next field as a signed */
/* offset from the address of the beginning of the element, rather than as a pointer. */

struct	GenLinkedOffsetList
{
	size_t		Head,
				Tail;
	size_t		LinkOffset;
};
typedef struct GenLinkedOffsetList	GenLinkedOffsetList;


void		InitLinkedOffsetList( GenLinkedOffsetList *pList, size_t linkOffset);

void		*GetHeadPtr( GenLinkedOffsetList *pList);
void		*GetTailPtr( GenLinkedOffsetList *pList);
void		*GetOffsetLink( GenLinkedOffsetList *pList, void *elem);

void		OffsetAddToHead( GenLinkedOffsetList *pList, void *elem);
void		OffsetAddToTail( GenLinkedOffsetList *pList, void *elem);

int		OffsetRemoveFromList( GenLinkedOffsetList *pList, void *elem);

int		OffsetReplaceElem( GenLinkedOffsetList *pList, void *elemInList, void *newElem);


#endif //	__GenLinkedList__