1 /* 2 * Copyright (c) 1988, 1989, 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Adam de Boor. 7 * 8 * Redistribution and use in source and binary forms are permitted 9 * provided that the above copyright notice and this paragraph are 10 * duplicated in all such forms and that any documentation, 11 * advertising materials, and other materials related to such 12 * distribution and use acknowledge that the software was developed 13 * by the University of California, Berkeley. The name of the 14 * University may not be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 */ 20 21 #ifndef lint 22 static char sccsid[] = "@(#)lstAppend.c 5.2 (Berkeley) 03/11/90"; 23 #endif /* not lint */ 24 25 /*- 26 * LstAppend.c -- 27 * Add a new node with a new datum after an existing node 28 */ 29 30 #include "lstInt.h" 31 32 /*- 33 *----------------------------------------------------------------------- 34 * Lst_Append -- 35 * Create a new node and add it to the given list after the given node. 36 * 37 * Results: 38 * SUCCESS if all went well. 39 * 40 * Side Effects: 41 * A new ListNode is created and linked in to the List. The lastPtr 42 * field of the List will be altered if ln is the last node in the 43 * list. lastPtr and firstPtr will alter if the list was empty and 44 * ln was NILLNODE. 45 * 46 *----------------------------------------------------------------------- 47 */ 48 ReturnStatus 49 Lst_Append (l, ln, d) 50 Lst l; /* affected list */ 51 LstNode ln; /* node after which to append the datum */ 52 ClientData d; /* said datum */ 53 { 54 register List list; 55 register ListNode lNode; 56 register ListNode nLNode; 57 58 if (LstValid (l) && (ln == NILLNODE && LstIsEmpty (l))) { 59 goto ok; 60 } 61 62 if (!LstValid (l) || LstIsEmpty (l) || ! LstNodeValid (ln, l)) { 63 return (FAILURE); 64 } 65 ok: 66 67 list = (List)l; 68 lNode = (ListNode)ln; 69 70 PAlloc (nLNode, ListNode); 71 nLNode->datum = d; 72 nLNode->useCount = nLNode->flags = 0; 73 74 if (lNode == NilListNode) { 75 if (list->isCirc) { 76 nLNode->nextPtr = nLNode->prevPtr = nLNode; 77 } else { 78 nLNode->nextPtr = nLNode->prevPtr = NilListNode; 79 } 80 list->firstPtr = list->lastPtr = nLNode; 81 } else { 82 nLNode->prevPtr = lNode; 83 nLNode->nextPtr = lNode->nextPtr; 84 85 lNode->nextPtr = nLNode; 86 if (nLNode->nextPtr != NilListNode) { 87 nLNode->nextPtr->prevPtr = nLNode; 88 } 89 90 if (lNode == list->lastPtr) { 91 list->lastPtr = nLNode; 92 } 93 } 94 95 return (SUCCESS); 96 } 97 98