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[] = "@(#)lstIndex.c 5.2 (Berkeley) 03/11/90"; 23 #endif /* not lint */ 24 25 /*- 26 * lstIndex.c -- 27 * Function to return the index of a datum in a Lst. 28 */ 29 30 #include "lstInt.h" 31 32 /*- 33 *----------------------------------------------------------------------- 34 * Lst_Index -- 35 * Return the index of a datum in a Lst. Indices start at 0. 36 * 37 * Results: 38 * Returns -1 if the datum isn't in the Lst, or the index of 39 * the datum if it is. 40 * 41 * Side Effects: 42 * None. 43 * 44 *----------------------------------------------------------------------- 45 */ 46 int 47 Lst_Index(l, d) 48 Lst l; 49 ClientData d; 50 { 51 List list = (List)l; 52 register ListNode lNode; 53 register int index; 54 55 lNode = list->firstPtr; 56 57 if (lNode == NilListNode) { 58 return(-1); 59 } 60 61 index = 0; 62 63 do { 64 if (lNode->datum == d) { 65 return(index); 66 } else { 67 lNode = lNode->nextPtr; 68 index += 1; 69 } 70 } while (lNode != NilListNode && lNode != list->firstPtr); 71 return(-1); 72 } 73