freebsd-dev/usr.bin/make/lst.lib/lstInsert.c
1999-08-28 01:08:13 +00:00

116 lines
3.6 KiB
C

/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* $FreeBSD$
*/
#ifndef lint
static char sccsid[] = "@(#)lstInsert.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
/*-
* LstInsert.c --
* Insert a new datum before an old one
*/
#include "lstInt.h"
/*-
*-----------------------------------------------------------------------
* Lst_Insert --
* Insert a new node with the given piece of data before the given
* node in the given list.
*
* Results:
* SUCCESS or FAILURE.
*
* Side Effects:
* the firstPtr field will be changed if ln is the first node in the
* list.
*
*-----------------------------------------------------------------------
*/
ReturnStatus
Lst_Insert (l, ln, d)
Lst l; /* list to manipulate */
LstNode ln; /* node before which to insert d */
ClientData d; /* datum to be inserted */
{
register ListNode nLNode; /* new lnode for d */
register ListNode lNode = (ListNode)ln;
register List list = (List)l;
/*
* check validity of arguments
*/
if (LstValid (l) && (LstIsEmpty (l) && ln == NILLNODE))
goto ok;
if (!LstValid (l) || LstIsEmpty (l) || !LstNodeValid (ln, l)) {
return (FAILURE);
}
ok:
PAlloc (nLNode, ListNode);
nLNode->datum = d;
nLNode->useCount = nLNode->flags = 0;
if (ln == NILLNODE) {
if (list->isCirc) {
nLNode->prevPtr = nLNode->nextPtr = nLNode;
} else {
nLNode->prevPtr = nLNode->nextPtr = NilListNode;
}
list->firstPtr = list->lastPtr = nLNode;
} else {
nLNode->prevPtr = lNode->prevPtr;
nLNode->nextPtr = lNode;
if (nLNode->prevPtr != NilListNode) {
nLNode->prevPtr->nextPtr = nLNode;
}
lNode->prevPtr = nLNode;
if (lNode == list->firstPtr) {
list->firstPtr = nLNode;
}
}
return (SUCCESS);
}