Cleanup watchdog.c, as described on the list.

1 files changed, 20 insertions, 100 deletions

diff --git a/toys/pending/watchdog.c b/toys/pending/watchdog.c
index 0813fe69..d1279bd4 100644
--- a/toys/pending/watchdog.c
+++ b/toys/pending/watchdog.c
@@ -1,128 +1,48 @@
 /* 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
 
- Author: Chris Sarra, chrissarra@google.com
- Date: 25 July 2019
- Ref: kernel.org/doc/Documentation/watchdog/watchdog-api.txt
-
-USE_WATCHDOG(NEWTOY(watchdog, "Ft#T#", TOYFLAG_NEEDROOT|TOYFLAG_BIN))
+USE_WATCHDOG(NEWTOY(watchdog, "<1>1Ft#=4<1T#=60<1", TOYFLAG_NEEDROOT|TOYFLAG_BIN))
 
 config WATCHDOG
   bool "watchdog"
-  default y
+  default n
   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)
+
+    -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"
 
-// Make sure no DEBUG variable is set; change this if you need debug prints!
-#undef WATCHDOG_DEBUG
-
-// Default timeout values in seconds.
-#define WATCHDOG_SW_TIMER_S_DEFAULT (4)
-#define WATCHDOG_HW_TIMER_S_DEFAULT (60)
-
 GLOBALS(
-  long hw_timer_s;
-  long sw_timer_s;
+  long T, t;
+
   int fd;
 )
 
-static int intercept_signals(void (*fn)(int)) {
-  int rc = 0;
-  struct sigaction sigact;
-  memset(&sigact, 0, sizeof(sigact));
-  sigact.sa_handler = fn;
-
-  rc = sigaction(SIGTERM, &sigact, NULL);
-#if defined(WATCHDOG_DEBUG)
-  if ( rc ) {
-    printf("failed to create new sigaction for SIGTERM: %d\n", rc);
-  }
-#endif
-  return rc;
-}
-
-void safe_shutdown(int __attribute__((unused))ignored) {
+void safe_shutdown(int ignored) {
   write(TT.fd, "V", 1);
   close(TT.fd);
-  TT.fd = -1;
   error_exit("safely exited watchdog.");
 }
 
-void watchdog_main(void) {
-  int rc = 0;
-  long hw_timer_sec = 0;
-  char *watchdog_dev = NULL;
-
-  if ( toys.optc > 0 ) {
-    watchdog_dev = toys.optargs[0];
-#if defined(WATCHDOG_DEBUG)
-    printf("using dev @ '%s'\n", watchdog_dev);
-#endif
-  } else {
-    error_exit("watchdog dev required");
-  }
-
-  // Set default values for timeouts if no flags
-  if (!(toys.optflags & FLAG_t)) {
-    TT.sw_timer_s = WATCHDOG_SW_TIMER_S_DEFAULT;
-#if defined(WATCHDOG_DEBUG)
-    printf("using default sw_timer_s.\n");
-#endif
-  }
-
-  if (!(toys.optflags & FLAG_T)) {
-    TT.hw_timer_s = WATCHDOG_HW_TIMER_S_DEFAULT;
-#if defined(WATCHDOG_DEBUG)
-    printf("using default hw_timer_s.\n");
-#endif
-  }
-
-#if defined(WATCHDOG_DEBUG)
-    printf("hw timer: %ld seconds\n", TT.hw_timer_s);
-    printf("sw timer: %ld seconds\n", TT.sw_timer_s);
-#endif
-
-  if (!(toys.optflags & FLAG_F)) {
-#if defined(WATCHDOG_DEBUG)
-      printf("daemonizing. so long, foreground!\n");
-#endif
-    // Attempt to daemonize
-    rc = daemon(1, 1);
-    if ( rc ) {
-      perror_exit("failed to daemonize: %d", rc);
-    }
-  }
-
-  // Intercept terminating signals so we can call our shutdown routine first.
-  if ( intercept_signals(safe_shutdown) ) {
-    perror_exit("failed to intercept desired signals: %d", rc);
-  }
-#if defined(WATCHDOG_DEBUG)
-    printf("Successfully intercepted signals.\n");
-#endif
-
-  TT.fd = open(watchdog_dev, O_WRONLY);
-  if ( TT.fd == -1 ) {
-    perror_exit("failed to open '%s'", watchdog_dev);
-  }
-
-#if defined(WDIOC_SETTIMEOUT)
-  // SETTIMEOUT takes time value in seconds: s = ms / (1000 ms/s)
-  hw_timer_sec = TT.hw_timer_s;
-  xioctl(TT.fd, WDIOC_SETTIMEOUT, (void *)&hw_timer_sec);
-#endif // WDIOC_SETTIMEOUT
+void watchdog_main(void)
+{
+  if (!FLAG(F) && daemon(1, 1)) perror_exit("failed to daemonize");
+  xsignal(SIGTERM, 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.
-  while (1) {
+  for (;;) {
     write(TT.fd, "\0", 1);
-    usleep(TT.sw_timer_s * 1000 * 1000);
+    sleep(TT.t);
   }
 }