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[] = "@(#)lstCur.c 5.2 (Berkeley) 03/11/90"; 23 #endif /* not lint */ 24 25 /*- 26 * LstCur.c -- 27 * Return the current node in the list. 28 * The sequential functions access the list in a slightly different way. 29 * CurPtr points to their idea of the current node in the list and they 30 * access the list based on it. Because the list is circular, Lst_Next 31 * and Lst_Prev will go around the list forever. Lst_IsAtEnd must be 32 * used to determine when to stop. 33 */ 34 35 #include "lstInt.h" 36 37 /*- 38 *----------------------------------------------------------------------- 39 * Lst_Cur -- 40 * Return the current node if the list is open for sequential 41 * access. 42 * 43 * Results: 44 * The current node or NILLNODE if the list isn't open.. 45 * 46 * Side Effects: 47 * None. 48 * 49 *----------------------------------------------------------------------- 50 */ 51 LstNode 52 Lst_Cur (l) 53 Lst l; 54 { 55 register List list = (List)l; 56 57 if ((LstValid(l) == FALSE) || 58 (list->isOpen == FALSE)) { 59 return (NILLNODE); 60 } else { 61 return ((LstNode)list->curPtr); 62 } 63 } 64 65