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Diffstat (limited to 'lst.lib/lstForEachFrom.c')
| -rw-r--r-- | lst.lib/lstForEachFrom.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/lst.lib/lstForEachFrom.c b/lst.lib/lstForEachFrom.c new file mode 100644 index 0000000..c7f44ad --- /dev/null +++ b/lst.lib/lstForEachFrom.c @@ -0,0 +1,125 @@ +/* $NetBSD: lstForEachFrom.c,v 1.17 2009/01/23 21:26:30 dsl Exp $ */ + +/* + * Copyright (c) 1988, 1989, 1990, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Adam de Boor. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef MAKE_NATIVE +static char rcsid[] = "$NetBSD: lstForEachFrom.c,v 1.17 2009/01/23 21:26:30 dsl Exp $"; +#else +#include <sys/cdefs.h> +#ifndef lint +#if 0 +static char sccsid[] = "@(#)lstForEachFrom.c 8.1 (Berkeley) 6/6/93"; +#else +__RCSID("$NetBSD: lstForEachFrom.c,v 1.17 2009/01/23 21:26:30 dsl Exp $"); +#endif +#endif /* not lint */ +#endif + +/*- + * lstForEachFrom.c -- + * Perform a given function on all elements of a list starting from + * a given point. + */ + +#include "lstInt.h" + +/*- + *----------------------------------------------------------------------- + * Lst_ForEachFrom -- + * Apply the given function to each element of the given list. The + * function should return 0 if traversal should continue and non- + * zero if it should abort. + * + * Results: + * None. + * + * Side Effects: + * Only those created by the passed-in function. + * + *----------------------------------------------------------------------- + */ +/*VARARGS2*/ +int +Lst_ForEachFrom(Lst l, LstNode ln, int (*proc)(void *, void *), + void *d) +{ + ListNode tln = ln; + List list = l; + ListNode next; + Boolean done; + int result; + + if (!LstValid (list) || LstIsEmpty (list)) { + return 0; + } + + do { + /* + * Take care of having the current element deleted out from under + * us. + */ + + next = tln->nextPtr; + + /* + * We're done with the traversal if + * - the next node to examine is the first in the queue or + * doesn't exist and + * - nothing's been added after the current node (check this + * after proc() has been called). + */ + done = (next == NULL || next == list->firstPtr); + + (void) tln->useCount++; + result = (*proc) (tln->datum, d); + (void) tln->useCount--; + + /* + * Now check whether a node has been added. + * Note: this doesn't work if this node was deleted before + * the new node was added. + */ + if (next != tln->nextPtr) { + next = tln->nextPtr; + done = 0; + } + + if (tln->flags & LN_DELETED) { + free((char *)tln); + } + tln = next; + } while (!result && !LstIsEmpty(list) && !done); + + return result; +} + |