79 lines
2.6 KiB
C
79 lines
2.6 KiB
C
/* $NetBSD: lstPrev.c,v 1.3 2008/12/13 15:19:29 dsl Exp $ */
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/*
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* Copyright (c) 1988, 1989, 1990, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Adam de Boor.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#ifndef MAKE_NATIVE
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static char rcsid[] = "$NetBSD: lstPrev.c,v 1.3 2008/12/13 15:19:29 dsl Exp $";
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#else
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#include <sys/cdefs.h>
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#ifndef lint
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#if 0
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static char sccsid[] = "@(#)lstSucc.c 8.1 (Berkeley) 6/6/93";
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#else
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__RCSID("$NetBSD: lstPrev.c,v 1.3 2008/12/13 15:19:29 dsl Exp $");
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#endif
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#endif /* not lint */
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#endif
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/*-
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* LstPrev.c --
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* return the predecessor to a given node
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*/
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#include "lstInt.h"
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/*-
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*-----------------------------------------------------------------------
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* Lst_Prev --
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* Return the predecessor to the given node on its list.
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*
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* Results:
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* The predecessor of the node, if it exists (note that on a circular
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* list, if the node is the only one in the list, it is its own
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* predecessor).
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*
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* Side Effects:
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* None.
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*
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*-----------------------------------------------------------------------
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*/
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LstNode
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Lst_Prev(LstNode ln)
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{
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if (ln == NULL) {
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return NULL;
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} else {
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return (ln->prevPtr);
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}
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}
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