1/* $NetBSD: lstForEachFrom.c,v 1.17 2009/01/23 21:26:30 dsl Exp $ */ 2 3/* 4 * Copyright (c) 1988, 1989, 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Adam de Boor. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#ifndef MAKE_NATIVE 36static char rcsid[] = "$NetBSD: lstForEachFrom.c,v 1.17 2009/01/23 21:26:30 dsl Exp $"; 37#else 38#include <sys/cdefs.h> 39#ifndef lint 40#if 0 41static char sccsid[] = "@(#)lstForEachFrom.c 8.1 (Berkeley) 6/6/93"; 42#else 43__RCSID("$NetBSD: lstForEachFrom.c,v 1.17 2009/01/23 21:26:30 dsl Exp $"); 44#endif 45#endif /* not lint */ 46#endif 47 48/*- 49 * lstForEachFrom.c -- 50 * Perform a given function on all elements of a list starting from 51 * a given point. 52 */ 53 54#include "lstInt.h" 55 56/*- 57 *----------------------------------------------------------------------- 58 * Lst_ForEachFrom -- 59 * Apply the given function to each element of the given list. The 60 * function should return 0 if traversal should continue and non- 61 * zero if it should abort. 62 * 63 * Results: 64 * None. 65 * 66 * Side Effects: 67 * Only those created by the passed-in function. 68 * 69 *----------------------------------------------------------------------- 70 */ 71/*VARARGS2*/ 72int 73Lst_ForEachFrom(Lst l, LstNode ln, int (*proc)(void *, void *), 74 void *d) 75{ 76 ListNode tln = ln; 77 List list = l; 78 ListNode next; 79 Boolean done; 80 int result; 81 82 if (!LstValid (list) || LstIsEmpty (list)) { 83 return 0; 84 } 85 86 do { 87 /* 88 * Take care of having the current element deleted out from under 89 * us. 90 */ 91 92 next = tln->nextPtr; 93 94 /* 95 * We're done with the traversal if 96 * - the next node to examine is the first in the queue or 97 * doesn't exist and 98 * - nothing's been added after the current node (check this 99 * after proc() has been called). 100 */ 101 done = (next == NULL || next == list->firstPtr); 102 103 (void) tln->useCount++; 104 result = (*proc) (tln->datum, d); 105 (void) tln->useCount--; 106 107 /* 108 * Now check whether a node has been added. 109 * Note: this doesn't work if this node was deleted before 110 * the new node was added. 111 */ 112 if (next != tln->nextPtr) { 113 next = tln->nextPtr; 114 done = 0; 115 } 116 117 if (tln->flags & LN_DELETED) { 118 free((char *)tln); 119 } 120 tln = next; 121 } while (!result && !LstIsEmpty(list) && !done); 122 123 return result; 124} 125 126