1 /* $OpenBSD: lstConcatDestroy.c,v 1.12 2022/12/26 19:16:02 jmc Exp $ */ 2 /* $NetBSD: lstConcat.c,v 1.6 1996/11/06 17:59:34 christos Exp $ */ 3 4 /* 5 * Copyright (c) 1988, 1989, 1990, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Adam de Boor. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 /*- 37 * listConcat.c -- 38 * Function to concatenate two lists. 39 */ 40 41 #include "lstInt.h" 42 #include <stddef.h> 43 44 /*- 45 *----------------------------------------------------------------------- 46 * Lst_ConcatDestroy -- 47 * Concatenate two lists. The elements of the second list are 48 * destructively added to the first list. If the elements should 49 * be duplicated to avoid confusion with another list, the 50 * Lst_Duplicate function should be called first. 51 * 52 * Side Effects: 53 * The second list is destroyed. 54 *----------------------------------------------------------------------- 55 */ 56 void 57 Lst_ConcatDestroy(Lst l1, Lst l2) 58 { 59 if (l2->firstPtr != NULL) { 60 /* 61 * So long as the second list isn't empty, we just link the 62 * first element of the second list to the last element of the 63 * first list. If the first list isn't empty, we then link the 64 * last element of the list to the first element of the second 65 * list The last element of the second list, if it exists, then 66 * becomes the last element of the first list. 67 */ 68 l2->firstPtr->prevPtr = l1->lastPtr; 69 if (l1->lastPtr != NULL) 70 l1->lastPtr->nextPtr = l2->firstPtr; 71 else 72 l1->firstPtr = l2->firstPtr; 73 l1->lastPtr = l2->lastPtr; 74 } 75 } 76 77