Remove some unused code pointed out by Tito, plus a slightly more graceful

[oweals/busybox.git] / miscutils / watchdog.c

diff --git a/miscutils/watchdog.c b/miscutils/watchdog.c
index 7026cc0054e856759f45c7bb36c983c37f4a7301..58a6065536f1d5c5b4da7ae28e38269eaaa69719 100644 (file)
--- a/miscutils/watchdog.c
+++ b/miscutils/watchdog.c
@@ -2,46 +2,61 @@
 /*
  * Mini watchdog implementation for busybox
  *
- * Copyright (C) 2000  spoon <spoon@ix.netcom.com>.
- *
- * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Copyright (C) 2003  Paul Mundt <lethal@linux-sh.org>
  *
+ * 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>
+#include "busybox.h"
+
+/* Userspace timer duration, in seconds */
+static unsigned int timer_duration = 30;
+
+/* Watchdog file descriptor */
+static int fd;
+
+static void watchdog_shutdown(int ATTRIBUTE_UNUSED unused)
+{
+       write(fd, "V", 1);      /* Magic */
+       close(fd);
+       exit(0);
+}
 
-extern int watchdog_main(int argc, char **argv)
+int watchdog_main(int argc, char **argv)
 {
-       int fd;
 
-       if (argc != 2) {
-               usage(watchdog_usage);
-       }
+       char *t_arg;
+       unsigned long flags;
+       flags = bb_getopt_ulflags(argc, argv, "t:", &t_arg);
+       if (flags & 1)
+               timer_duration = bb_xgetlarg(t_arg, 10, 0, INT_MAX);
 
-       if ((fd=open(argv[1], O_WRONLY)) == -1) {
-               perror_msg_and_die(argv[1]);
-       }
+       /* We're only interested in the watchdog device .. */
+       if (optind < argc - 1 || argc == 1)
+               bb_show_usage();
+
+       bb_xdaemon(0, 1);
+
+       signal(SIGHUP, watchdog_shutdown);
+       signal(SIGINT, watchdog_shutdown);
+
+       fd = bb_xopen(argv[argc - 1], O_WRONLY);
 
        while (1) {
-               sleep(30);
+               /*
+                * 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);
        }
 
-       return EXIT_FAILURE;
+       watchdog_shutdown(0);
+
+       return EXIT_SUCCESS;
 }