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/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   signal handling functions

   Copyright (C) Andrew Tridgell 1998
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"


/****************************************************************************
catch child exits
****************************************************************************/
static void sig_cld(int signum)
{
	while (sys_waitpid((pid_t)-1,(int *)NULL, WNOHANG) > 0) ;

	CatchSignal(SIGCLD, SIG_IGN);
}



/*******************************************************************
block sigs
********************************************************************/
void BlockSignals(BOOL block,int signum)
{
#ifdef HAVE_SIGPROCMASK
	sigset_t set;
	sigemptyset(&set);
	sigaddset(&set,signum);
	sigprocmask(block?SIG_BLOCK:SIG_UNBLOCK,&set,NULL);
#elif defined(HAVE_SIGBLOCK)
	int block_mask = sigmask(signum);
	static int oldmask = 0;
	if (block) {
		oldmask = sigblock(block_mask);
	} else {
		sigsetmask(oldmask);
	}
#else
	/* yikes! This platform can't block signals? */
	static int done;
	if (!done) {
		DEBUG(0,("WARNING: No signal blocking available\n"));
		done=1;
	}
#endif
}



/*******************************************************************
catch a signal. This should implement the following semantics:

1) the handler remains installed after being called
2) the signal should be blocked during handler execution
********************************************************************/
void CatchSignal(int signum,void (*handler)(int ))
{
#ifdef HAVE_SIGACTION
	struct sigaction act;

	memset(&act, 0, sizeof(act));

	act.sa_handler = handler;
#ifdef SA_RESTART
	act.sa_flags = SA_RESTART;
#endif
	sigemptyset(&act.sa_mask);
	sigaddset(&act.sa_mask,signum);
	sigaction(signum,&act,NULL);
#else
	/* FIXME: need to handle sigvec and systems with broken signal() */
	signal(signum, handler);
#endif
}



/*******************************************************************
ignore SIGCLD via whatever means is necessary for this OS
********************************************************************/
void CatchChild(void)
{
	CatchSignal(SIGCLD, sig_cld);
}