Promote watchdog.

1 files changed, 50 insertions, 0 deletions

diff --git a/toys/other/watchdog.c b/toys/other/watchdog.c
new file mode 100644
index 00000000..7a49c0b0
--- /dev/null
+++ b/toys/other/watchdog.c
@@ -0,0 +1,50 @@
+/* watchdog - start a watchdog timer with configurable kick frequencies
+ *
+ * Copyright 2019 Chris Sarra <chrissarra@google.com>
+ *
+ * See kernel.org/doc/Documentation/watchdog/watchdog-api.txt
+
+USE_WATCHDOG(NEWTOY(watchdog, "<1>1Ft#=4<1T#=60<1", TOYFLAG_NEEDROOT|TOYFLAG_BIN))
+
+config WATCHDOG
+  bool "watchdog"
+  default y
+  depends on TOYBOX_FORK
+  help
+    usage: watchdog [-F] [-t SW_TIMER_S] [-T HW_TIMER_S] DEV
+
+    Start the watchdog timer at DEV with optional timeout parameters.
+
+    -F	run in the foreground (do not daemonize)
+    -t	software timer (in seconds)
+    -T	hardware timer (in seconds)
+*/
+#define FOR_watchdog
+#include "toys.h"
+#include "linux/watchdog.h"
+
+GLOBALS(
+  long T, t;
+
+  int fd;
+)
+
+void safe_shutdown(int ignored) {
+  write(TT.fd, "V", 1);
+  close(TT.fd);
+  error_exit("safely exited watchdog.");
+}
+
+void watchdog_main(void)
+{
+  if (!FLAG(F) && daemon(1, 1)) perror_exit("failed to daemonize");
+  xsignal(SIGTERM, safe_shutdown);
+  xsignal(SIGINT, safe_shutdown);
+  xioctl(TT.fd = xopen(*toys.optargs, O_WRONLY), WDIOC_SETTIMEOUT, &TT.T);
+
+  // Now that we've got the watchdog device open, kick it periodically.
+  for (;;) {
+    write(TT.fd, "", 1);
+    sleep(TT.t);
+  }
+}