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
Lst_Cur(l)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