init/initd/signal_linux.c

/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
 * Copyright (C) 2018 - David Oberhollenzer
 *
 * 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 3 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, see <https://www.gnu.org/licenses/>.
 */
#include <stdio.h>

#include "init.h"

int sigsetup(void)
{
	sigset_t mask;
	int sfd;

	sigfillset(&mask);
	if (sigprocmask(SIG_SETMASK, &mask, NULL) == -1) {
		perror("sigprocmask");
		return -1;
	}

	sigemptyset(&mask);
	sigaddset(&mask, SIGCHLD);
	sigaddset(&mask, SIGINT);
	sigaddset(&mask, SIGTERM);

	sfd = signalfd(-1, &mask, SFD_CLOEXEC);
	if (sfd == -1) {
		perror("signalfd");
		return -1;
	}

	if (reboot(LINUX_REBOOT_CMD_CAD_OFF))
		perror("cannot disable CTRL+ALT+DEL");

	return sfd;
}

void sigreset(void)
{
	sigset_t mask;

	sigemptyset(&mask);
	sigprocmask(SIG_SETMASK, &mask, NULL);
}