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Diffstat (limited to '20130123/lst.lib/lstOpen.c')
| -rw-r--r-- | 20130123/lst.lib/lstOpen.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/20130123/lst.lib/lstOpen.c b/20130123/lst.lib/lstOpen.c new file mode 100644 index 0000000..941293e --- /dev/null +++ b/20130123/lst.lib/lstOpen.c @@ -0,0 +1,87 @@ +/* $NetBSD: lstOpen.c,v 1.12 2008/12/13 15:19:29 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: lstOpen.c,v 1.12 2008/12/13 15:19:29 dsl Exp $"; +#else +#include <sys/cdefs.h> +#ifndef lint +#if 0 +static char sccsid[] = "@(#)lstOpen.c 8.1 (Berkeley) 6/6/93"; +#else +__RCSID("$NetBSD: lstOpen.c,v 1.12 2008/12/13 15:19:29 dsl Exp $"); +#endif +#endif /* not lint */ +#endif + +/*- + * LstOpen.c -- + * Open a list for sequential access. The sequential functions access the + * list in a slightly different way. CurPtr points to their idea of the + * current node in the list and they access the list based on it. + * If the list is circular, Lst_Next and Lst_Prev will go around + * the list forever. Lst_IsAtEnd must be used to determine when to stop. + */ + +#include "lstInt.h" + +/*- + *----------------------------------------------------------------------- + * Lst_Open -- + * Open a list for sequential access. A list can still be searched, + * etc., without confusing these functions. + * + * Results: + * SUCCESS or FAILURE. + * + * Side Effects: + * isOpen is set TRUE and curPtr is set to NULL so the + * other sequential functions no it was just opened and can choose + * the first element accessed based on this. + * + *----------------------------------------------------------------------- + */ +ReturnStatus +Lst_Open(Lst l) +{ + if (LstValid (l) == FALSE) { + return (FAILURE); + } + (l)->isOpen = TRUE; + (l)->atEnd = LstIsEmpty (l) ? Head : Unknown; + (l)->curPtr = NULL; + + return (SUCCESS); +} + |
