1236769Sobrien/* $NetBSD: lstIsAtEnd.c,v 1.13 2008/02/15 21:29:50 christos Exp $ */ 2236769Sobrien 3236769Sobrien/* 4236769Sobrien * Copyright (c) 1988, 1989, 1990, 1993 5236769Sobrien * The Regents of the University of California. All rights reserved. 6236769Sobrien * 7236769Sobrien * This code is derived from software contributed to Berkeley by 8236769Sobrien * Adam de Boor. 9236769Sobrien * 10236769Sobrien * Redistribution and use in source and binary forms, with or without 11236769Sobrien * modification, are permitted provided that the following conditions 12236769Sobrien * are met: 13236769Sobrien * 1. Redistributions of source code must retain the above copyright 14236769Sobrien * notice, this list of conditions and the following disclaimer. 15236769Sobrien * 2. Redistributions in binary form must reproduce the above copyright 16236769Sobrien * notice, this list of conditions and the following disclaimer in the 17236769Sobrien * documentation and/or other materials provided with the distribution. 18236769Sobrien * 3. Neither the name of the University nor the names of its contributors 19236769Sobrien * may be used to endorse or promote products derived from this software 20236769Sobrien * without specific prior written permission. 21236769Sobrien * 22236769Sobrien * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23236769Sobrien * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24236769Sobrien * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25236769Sobrien * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26236769Sobrien * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27236769Sobrien * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28236769Sobrien * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29236769Sobrien * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30236769Sobrien * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31236769Sobrien * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32236769Sobrien * SUCH DAMAGE. 33236769Sobrien */ 34236769Sobrien 35236769Sobrien#ifndef MAKE_NATIVE 36236769Sobrienstatic char rcsid[] = "$NetBSD: lstIsAtEnd.c,v 1.13 2008/02/15 21:29:50 christos Exp $"; 37236769Sobrien#else 38236769Sobrien#include <sys/cdefs.h> 39236769Sobrien#ifndef lint 40236769Sobrien#if 0 41236769Sobrienstatic char sccsid[] = "@(#)lstIsAtEnd.c 8.1 (Berkeley) 6/6/93"; 42236769Sobrien#else 43236769Sobrien__RCSID("$NetBSD: lstIsAtEnd.c,v 1.13 2008/02/15 21:29:50 christos Exp $"); 44236769Sobrien#endif 45236769Sobrien#endif /* not lint */ 46236769Sobrien#endif 47236769Sobrien 48236769Sobrien/*- 49236769Sobrien * LstIsAtEnd.c -- 50236769Sobrien * Tell if the current node is at the end of the list. 51236769Sobrien * The sequential functions access the list in a slightly different way. 52236769Sobrien * CurPtr points to their idea of the current node in the list and they 53236769Sobrien * access the list based on it. Because the list is circular, Lst_Next 54236769Sobrien * and Lst_Prev will go around the list forever. Lst_IsAtEnd must be 55236769Sobrien * used to determine when to stop. 56236769Sobrien */ 57236769Sobrien 58236769Sobrien#include "lstInt.h" 59236769Sobrien 60236769Sobrien/*- 61236769Sobrien *----------------------------------------------------------------------- 62236769Sobrien * Lst_IsAtEnd -- 63236769Sobrien * Return true if have reached the end of the given list. 64236769Sobrien * 65236769Sobrien * Results: 66236769Sobrien * TRUE if at the end of the list (this includes the list not being 67236769Sobrien * open or being invalid) or FALSE if not. We return TRUE if the list 68236769Sobrien * is invalid or unopend so as to cause the caller to exit its loop 69236769Sobrien * asap, the assumption being that the loop is of the form 70236769Sobrien * while (!Lst_IsAtEnd (l)) { 71236769Sobrien * ... 72236769Sobrien * } 73236769Sobrien * 74236769Sobrien * Side Effects: 75236769Sobrien * None. 76236769Sobrien * 77236769Sobrien *----------------------------------------------------------------------- 78236769Sobrien */ 79236769SobrienBoolean 80236769SobrienLst_IsAtEnd(Lst l) 81236769Sobrien{ 82236769Sobrien List list = l; 83236769Sobrien 84236769Sobrien return (!LstValid (l) || !list->isOpen || 85236769Sobrien (list->atEnd == Head) || (list->atEnd == Tail)); 86236769Sobrien} 87236769Sobrien 88