diff options
Diffstat (limited to 'contrib/tcpdump/setsignal.c')
-rw-r--r-- | contrib/tcpdump/setsignal.c | 93 |
1 files changed, 0 insertions, 93 deletions
diff --git a/contrib/tcpdump/setsignal.c b/contrib/tcpdump/setsignal.c deleted file mode 100644 index dbb8678..0000000 --- a/contrib/tcpdump/setsignal.c +++ /dev/null @@ -1,93 +0,0 @@ -/* - * 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[] _U_ = - "@(#) $Header: /tcpdump/master/tcpdump/setsignal.c,v 1.11 2003/11/16 09:36:42 guy Exp $ (LBL)"; -#endif - -#ifdef HAVE_CONFIG_H -#include "config.h" -#endif - -#include <tcpdump-stdinc.h> - -#include <signal.h> -#ifdef HAVE_SIGACTION -#include <string.h> -#endif - -#ifdef HAVE_OS_PROTO_H -#include "os-proto.h" -#endif - -#include "setsignal.h" - -/* - * An OS-independent signal() with, whenever possible, partial BSD - * semantics, i.e. the signal handler is restored following service - * of the signal, but system calls are *not* restarted, so that if - * "pcap_breakloop()" is called in a signal handler in a live capture, - * the read/recvfrom/whatever in the live capture doesn't get restarted, - * it returns -1 and sets "errno" to EINTR, so we can break out of the - * live capture loop. - * - * We use "sigaction()" if available. We don't specify that the signal - * should restart system calls, so that should always do what we want. - * - * Otherwise, if "sigset()" is available, it probably has BSD semantics - * while "signal()" has traditional semantics, so we use "sigset()"; it - * might cause system calls to be restarted for the signal, however. - * I don't know whether, in any systems where it did cause system calls to - * be restarted, there was a way to ask it not to do so; there may no - * longer be any interesting systems without "sigaction()", however, - * and, if there are, they might have "sigvec()" with SV_INTERRUPT - * (which I think first appeared in 4.3BSD). - * - * Otherwise, we use "signal()" - which means we might get traditional - * semantics, wherein system calls don't get restarted *but* the - * signal handler is reset to SIG_DFL and the signal is not blocked, - * so that a subsequent signal would kill the process immediately. - * - * Did I mention that signals suck? At least in POSIX-compliant systems - * they suck far less, as those systems have "sigaction()". - */ -RETSIGTYPE -(*setsignal (int sig, RETSIGTYPE (*func)(int)))(int) -{ -#ifdef HAVE_SIGACTION - struct sigaction old, new; - - memset(&new, 0, sizeof(new)); - new.sa_handler = func; - 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 -} - |