xref: /openbsd/lib/libc/sys/semctl.c (revision 5af055cd)
1 /*	$OpenBSD: semctl.c,v 1.9 2015/09/14 12:08:22 guenther Exp $ */
2 /*
3  * Copyright (c) 1994, 1995 Christopher G. Demetriou
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Christopher G. Demetriou
17  *	for the NetBSD Project.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/sem.h>
34 #include <stdarg.h>
35 #include <stdlib.h>
36 
37 int
38 semctl(int semid, int semnum, int cmd, ...)
39 {
40 	va_list ap;
41 	union semun semun;
42 	union semun *semun_ptr = NULL;
43 
44 	va_start(ap, cmd);
45 	if (cmd == IPC_SET || cmd == IPC_STAT || cmd == GETALL ||
46 	    cmd == SETVAL || cmd == SETALL) {
47 		semun = va_arg(ap, union semun);
48 		semun_ptr = &semun;
49 	}
50 	va_end(ap);
51 
52 	return (__semctl(semid, semnum, cmd, semun_ptr));
53 }
54