freebsd-dev/usr.bin/make/lst.lib/lstFirst.c
Will Andrews 98c28d6cc5 There's no reason to use fancy forms of NULL. Replace all instances
of NIL, NILLST, NILLGNODE, etc. with NULL.

Obtained from:		OpenBSD
2000-12-02 18:58:01 +00:00

75 lines
2.5 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.
*
* @(#)lstFirst.c 8.1 (Berkeley) 6/6/93
*/
#ifndef lint
#include <sys/cdefs.h>
__RCSID("$FreeBSD$");
#endif /* not lint */
/*-
* LstFirst.c --
* Return the first node of a list
*/
#include "lstInt.h"
/*-
*-----------------------------------------------------------------------
* Lst_First --
* Return the first node on the given list.
*
* Results:
* The first node or NULL if the list is empty.
*
* Side Effects:
* None.
*
*-----------------------------------------------------------------------
*/
LstNode
Lst_First (l)
Lst l;
{
if (!LstValid (l) || LstIsEmpty (l)) {
return (NULL);
} else {
return ((LstNode)((List)l)->firstPtr);
}
}