mirror of
https://github.com/sheumann/hush.git
synced 2024-08-16 09:29:16 +00:00
71 lines
1.5 KiB
C
71 lines
1.5 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* Mini watchdog implementation for busybox
|
|
*
|
|
* Copyright (C) 2003 Paul Mundt <lethal@linux-sh.org>
|
|
* Copyright (C) 2006 Bernhard Fischer <busybox@busybox.net>
|
|
*
|
|
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
|
|
*/
|
|
|
|
#include "busybox.h"
|
|
#include <stdio.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
#include <stdlib.h>
|
|
#include <signal.h>
|
|
|
|
#define OPT_FOREGROUND 0x01
|
|
#define OPT_TIMER 0x02
|
|
|
|
/* Watchdog file descriptor */
|
|
static int fd;
|
|
|
|
static void watchdog_shutdown(int ATTRIBUTE_UNUSED unused)
|
|
{
|
|
write(fd, "V", 1); /* Magic, see watchdog-api.txt in kernel */
|
|
close(fd);
|
|
exit(0);
|
|
}
|
|
|
|
int watchdog_main(int argc, char **argv)
|
|
{
|
|
unsigned long opts;
|
|
unsigned long timer_duration = 30; /* Userspace timer duration, in seconds */
|
|
char *t_arg;
|
|
|
|
opts = bb_getopt_ulflags(argc, argv, "Ft:", &t_arg);
|
|
|
|
if (opts & OPT_TIMER)
|
|
timer_duration = bb_xgetlarg(t_arg, 10, 0, INT_MAX);
|
|
|
|
/* We're only interested in the watchdog device .. */
|
|
if (optind < argc - 1 || argc == 1)
|
|
bb_show_usage();
|
|
|
|
#ifdef BB_NOMMU
|
|
if (!(opts & OPT_FOREGROUND))
|
|
vfork_daemon_rexec(0, 1, argc, argv, "-F");
|
|
#else
|
|
bb_xdaemon(0, 1);
|
|
#endif
|
|
|
|
signal(SIGHUP, watchdog_shutdown);
|
|
signal(SIGINT, watchdog_shutdown);
|
|
|
|
fd = bb_xopen(argv[argc - 1], O_WRONLY);
|
|
|
|
while (1) {
|
|
/*
|
|
* Make sure we clear the counter before sleeping, as the counter value
|
|
* is undefined at this point -- PFM
|
|
*/
|
|
write(fd, "\0", 1);
|
|
sleep(timer_duration);
|
|
}
|
|
|
|
watchdog_shutdown(0);
|
|
|
|
return EXIT_SUCCESS;
|
|
}
|