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/*
* Copyright (c) 1988, 1989, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Adam de Boor.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*/
#ifndef lint
static char sccsid[] = "@(#)lstIsAtEnd.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
/*-
* LstIsAtEnd.c --
* Tell if the current node is at the end of the list.
* The sequential functions access the list in a slightly different way.
* CurPtr points to their idea of the current node in the list and they
* access the list based on it. Because the list is circular, Lst_Next
* and Lst_Prev will go around the list forever. Lst_IsAtEnd must be
* used to determine when to stop.
*/
#include "lstInt.h"
/*-
*-----------------------------------------------------------------------
* Lst_IsAtEnd --
* Return true if have reached the end of the given list.
*
* Results:
* TRUE if at the end of the list (this includes the list not being
* open or being invalid) or FALSE if not. We return TRUE if the list
* is invalid or unopend so as to cause the caller to exit its loop
* asap, the assumption being that the loop is of the form
* while (!Lst_IsAtEnd (l)) {
* ...
* }
*
* Side Effects:
* None.
*
*-----------------------------------------------------------------------
*/
Boolean
Lst_IsAtEnd (l)
Lst l;
{
register List list = (List) l;
return (!LstValid (l) || !list->isOpen ||
(list->atEnd == Head) || (list->atEnd == Tail));
}
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