1 /* $OpenPackages$ */ 2 /* $OpenBSD: lstRemove.c,v 1.14 2003/06/03 02:56:12 millert 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. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 /*- 38 * LstRemove.c -- 39 * Remove an element from a list 40 */ 41 42 #include "lstInt.h" 43 #include <stdlib.h> 44 45 46 /*- 47 *----------------------------------------------------------------------- 48 * Lst_Remove -- 49 * Remove the given node from the given list. 50 * 51 * Side Effects: 52 * The list's firstPtr will be set to NULL if ln is the last 53 * node on the list. firsPtr and lastPtr will be altered if ln is 54 * either the first or last node, respectively, on the list. 55 * 56 *----------------------------------------------------------------------- 57 */ 58 void 59 Lst_Remove(l, ln) 60 Lst l; 61 LstNode ln; 62 { 63 if (ln == NULL) 64 return; 65 66 /* unlink it from the list */ 67 if (ln->nextPtr != NULL) 68 ln->nextPtr->prevPtr = ln->prevPtr; 69 if (ln->prevPtr != NULL) 70 ln->prevPtr->nextPtr = ln->nextPtr; 71 72 /* if either the firstPtr or lastPtr of the list point to this node, 73 * adjust them accordingly */ 74 if (l->firstPtr == ln) 75 l->firstPtr = ln->nextPtr; 76 if (l->lastPtr == ln) 77 l->lastPtr = ln->prevPtr; 78 79 /* note that the datum is unmolested. The caller must free it as 80 * necessary and as expected. */ 81 free(ln); 82 } 83 84