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/* $OpenBSD: setsignal.c,v 1.2 2000/10/03 14:31:59 ho Exp $ */
/*
* Copyright (c) 1997
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#ifndef lint
static const char rcsid[] =
"@(#) $Header: /cvs/OpenBSD/src/usr.sbin/tcpdump/setsignal.c,v 1.2 2000/10/03 14:31:59 ho Exp $ (LBL)";
#endif
#include <sys/types.h>
#ifdef HAVE_MEMORY_H
#include <memory.h>
#endif
#include <signal.h>
#ifdef HAVE_SIGACTION
#include <string.h>
#endif
#include "gnuc.h"
#ifdef HAVE_OS_PROTO_H
#include "os-proto.h"
#endif
#include "setsignal.h"
/*
* An os independent signal() with BSD semantics, e.g. the signal
* catcher is restored following service of the signal.
*
* When sigset() is available, signal() has SYSV semantics and sigset()
* has BSD semantics and call interface. Unfortunately, Linux does not
* have sigset() so we use the more complicated sigaction() interface
* there.
*
* Did I mention that signals suck?
*/
RETSIGTYPE
(*setsignal (int sig, RETSIGTYPE (*func)(int)))(int)
{
#ifdef HAVE_SIGACTION
struct sigaction old, new;
memset(&new, 0, sizeof(new));
new.sa_handler = func;
#ifdef SA_RESTART
new.sa_flags |= SA_RESTART;
#endif
if (sigaction(sig, &new, &old) < 0)
return (SIG_ERR);
return (old.sa_handler);
#else
#ifdef HAVE_SIGSET
return (sigset(sig, func));
#else
return (signal(sig, func));
#endif
#endif
}
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