xref: /freebsd/usr.sbin/ppp/sig.c (revision f5ff0f7c992c13c705491c0d38015bf59ebd6b58)

/*-
 * Copyright (c) 1997
 *	Brian Somers <brian@awfulhak.demon.co.uk>.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. 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
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $Id: sig.c,v 1.4 1997/02/25 14:05:10 brian Exp $
 *
 *  TODO:
 *
 */

#include <sys/cdefs.h>
#include "sig.h"
#include <sys/types.h>
#include <signal.h>
#include "mbuf.h"
#include "log.h"

static caused[NSIG];		/* An array of pending signals */
static sig_type handler[NSIG];	/* all start at SIG_DFL */


/* Record a signal in the "caused" array */

static void signal_recorder(int sig) {
        caused[sig-1]++;
}


/*
    set up signal_recorder, and record handler as the function to ultimately
    call in handle_signal()
*/

sig_type pending_signal(int sig,sig_type fn) {
    sig_type Result;

    if (sig <= 0 || sig > NSIG) {
	/* Oops - we must be a bit out of date (too many sigs ?) */
        logprintf("Eeek! %s:%s: I must be out of date!\n",__FILE__,__LINE__);
        return signal(sig,fn);
    }

    Result = handler[sig-1];
    if (fn == SIG_DFL || fn == SIG_IGN) {
        signal(sig,fn);
        handler[sig-1] = (sig_type)0;
    } else {
        handler[sig-1] = fn;
        signal(sig,signal_recorder);
    }
    caused[sig-1] = 0;
    return Result;
}


/* Call the handlers for any pending signals */

void handle_signals() {
    int sig;
    int got;

    do {
       got = 0;
       for (sig = 0; sig < NSIG; sig++)
           if (caused[sig]) {
               caused[sig]--;
               got++;
               (*handler[sig])(sig+1);
           }
    } while(got);
}