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/**
* mds — A micro-display server
* Copyright © 2014 Mattias Andrée (maandree@member.fsf.org)
*
* 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 <http://www.gnu.org/licenses/>.
*/
#include "signals.h"
#include "globals.h"
#include "client.h"
#include <libmdsserver/linked-list.h>
#include <libmdsserver/macros.h>
#include <libmdsserver/util.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <pthread.h>
#include <signal.h>
/**
* Send a singal to all threads except the current thread
*
* @param signo The signal
*/
static void signal_all(int signo)
{
pthread_t current_thread;
ssize_t node;
current_thread = pthread_self();
if (pthread_equal(current_thread, master_thread) == 0)
pthread_kill(master_thread, signo);
with_mutex (slave_mutex,
foreach_linked_list_node (client_list, node)
{
client_t* value = (client_t*)(void*)(client_list.values[node]);
if (pthread_equal(current_thread, value->thread) == 0)
pthread_kill(value->thread, signo);
}
);
}
/**
* Called with the signal SIGUSR1 is caught.
* This function should cue a re-exec of the program.
*
* @param signo The caught signal
*/
static void sigusr1_trap(int signo)
{
if (reexecing == 0)
{
terminating = reexecing = 1;
eprint("re-exec signal received.");
signal_all(signo);
}
}
/**
* Called with the signal SIGTERM is caught.
* This function should cue a termination of the program.
*
* @param signo The caught signal
*/
static void sigterm_trap(int signo)
{
if (terminating == 0)
{
terminating = 1;
eprint("terminate signal received.");
signal_all(signo);
}
}
/**
* Called with the signal SIGINT is caught.
* This function should cue a termination of the program.
*
* @param signo The caught signal
*/
static void sigint_trap(int signo)
{
if (terminating == 0)
{
terminating = 1;
eprint("terminal interrupt signal received.");
signal_all(signo);
}
}
/**
* Set up signal traps for all especially handled signals
*
* @return Zero on success, -1 on error
*/
int trap_signals(void)
{
/* Make the server update without all slaves dying on SIGUSR1. */
fail_if (xsigaction(SIGUSR1, sigusr1_trap) < 0);
/* Implement clean exit on SIGTERM. */
fail_if (xsigaction(SIGTERM, sigterm_trap) < 0);
/* Implement clean exit on SIGINT. */
fail_if (xsigaction(SIGINT, sigint_trap) < 0);
return 0;
pfail:
return -1;
}
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