gecko-dev/nsprpub/pr/include/prclist.h
1999-04-21 21:40:44 +00:00

122 lines
2.8 KiB
C

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/*
* The contents of this file are subject to the Netscape Public License
* Version 1.1 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#ifndef prclist_h___
#define prclist_h___
#include "prtypes.h"
typedef struct PRCListStr PRCList;
/*
** Circular linked list
*/
struct PRCListStr {
PRCList *next;
PRCList *prev;
};
/*
** Insert element "_e" into the list, before "_l".
*/
#define PR_INSERT_BEFORE(_e,_l) \
PR_BEGIN_MACRO \
(_e)->next = (_l); \
(_e)->prev = (_l)->prev; \
(_l)->prev->next = (_e); \
(_l)->prev = (_e); \
PR_END_MACRO
/*
** Insert element "_e" into the list, after "_l".
*/
#define PR_INSERT_AFTER(_e,_l) \
PR_BEGIN_MACRO \
(_e)->next = (_l)->next; \
(_e)->prev = (_l); \
(_l)->next->prev = (_e); \
(_l)->next = (_e); \
PR_END_MACRO
/*
** Return the element following element "_e"
*/
#define PR_NEXT_LINK(_e) \
((_e)->next)
/*
** Return the element preceding element "_e"
*/
#define PR_PREV_LINK(_e) \
((_e)->prev)
/*
** Append an element "_e" to the end of the list "_l"
*/
#define PR_APPEND_LINK(_e,_l) PR_INSERT_BEFORE(_e,_l)
/*
** Insert an element "_e" at the head of the list "_l"
*/
#define PR_INSERT_LINK(_e,_l) PR_INSERT_AFTER(_e,_l)
/* Return the head/tail of the list */
#define PR_LIST_HEAD(_l) (_l)->next
#define PR_LIST_TAIL(_l) (_l)->prev
/*
** Remove the element "_e" from it's circular list.
*/
#define PR_REMOVE_LINK(_e) \
PR_BEGIN_MACRO \
(_e)->prev->next = (_e)->next; \
(_e)->next->prev = (_e)->prev; \
PR_END_MACRO
/*
** Remove the element "_e" from it's circular list. Also initializes the
** linkage.
*/
#define PR_REMOVE_AND_INIT_LINK(_e) \
PR_BEGIN_MACRO \
(_e)->prev->next = (_e)->next; \
(_e)->next->prev = (_e)->prev; \
(_e)->next = (_e); \
(_e)->prev = (_e); \
PR_END_MACRO
/*
** Return non-zero if the given circular list "_l" is empty, zero if the
** circular list is not empty
*/
#define PR_CLIST_IS_EMPTY(_l) \
((_l)->next == (_l))
/*
** Initialize a circular list
*/
#define PR_INIT_CLIST(_l) \
PR_BEGIN_MACRO \
(_l)->next = (_l); \
(_l)->prev = (_l); \
PR_END_MACRO
#define PR_INIT_STATIC_CLIST(_l) \
{(_l), (_l)}
#endif /* prclist_h___ */