xref: /netbsd-src/lib/libc/gen/signal.c (revision ee38224d2ec73fe143b5ebe4f061036fb9df44f7)
1 /*	$NetBSD: signal.c,v 1.7 1995/03/04 01:56:04 cgd Exp $	*/
2 
3 /*
4  * Copyright (c) 1985, 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #if defined(LIBC_SCCS) && !defined(lint)
37 #if 0
38 static char sccsid[] = "@(#)signal.c	8.1 (Berkeley) 6/4/93";
39 #else
40 static char rcsid[] = "$NetBSD: signal.c,v 1.7 1995/03/04 01:56:04 cgd Exp $";
41 #endif
42 #endif /* LIBC_SCCS and not lint */
43 
44 /*
45  * Almost backwards compatible signal.
46  */
47 #include <signal.h>
48 
49 sigset_t __sigintr;		/* shared with siginterrupt */
50 
51 sig_t
52 signal(s, a)
53 	int s;
54 	sig_t a;
55 {
56 	struct sigaction sa, osa;
57 
58 	sa.sa_handler = a;
59 	sigemptyset(&sa.sa_mask);
60 	sa.sa_flags = 0;
61 	if (!sigismember(&__sigintr, s))
62 		sa.sa_flags |= SA_RESTART;
63 	if (sigaction(s, &sa, &osa) < 0)
64 		return (SIG_ERR);
65 	return (osa.sa_handler);
66 }
67