1 /* $OpenPackages$ */ 2 /* $OpenBSD: lstRemove.c,v 1.13 2001/05/29 12:53:47 espie Exp $ */ 3 /* $NetBSD: lstRemove.c,v 1.5 1996/11/06 17:59:50 christos Exp $ */ 4 5 /* 6 * Copyright (c) 1988, 1989, 1990, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * Adam de Boor. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 */ 40 41 /*- 42 * LstRemove.c -- 43 * Remove an element from a list 44 */ 45 46 #include "lstInt.h" 47 #include <stdlib.h> 48 49 50 /*- 51 *----------------------------------------------------------------------- 52 * Lst_Remove -- 53 * Remove the given node from the given list. 54 * 55 * Side Effects: 56 * The list's firstPtr will be set to NULL if ln is the last 57 * node on the list. firsPtr and lastPtr will be altered if ln is 58 * either the first or last node, respectively, on the list. 59 * 60 *----------------------------------------------------------------------- 61 */ 62 void 63 Lst_Remove(l, ln) 64 Lst l; 65 LstNode ln; 66 { 67 if (ln == NULL) 68 return; 69 70 /* unlink it from the list */ 71 if (ln->nextPtr != NULL) 72 ln->nextPtr->prevPtr = ln->prevPtr; 73 if (ln->prevPtr != NULL) 74 ln->prevPtr->nextPtr = ln->nextPtr; 75 76 /* if either the firstPtr or lastPtr of the list point to this node, 77 * adjust them accordingly */ 78 if (l->firstPtr == ln) 79 l->firstPtr = ln->nextPtr; 80 if (l->lastPtr == ln) 81 l->lastPtr = ln->prevPtr; 82 83 /* note that the datum is unmolested. The caller must free it as 84 * necessary and as expected. */ 85 free(ln); 86 } 87 88