Documentation/watchdog/src/watchdog-test.c

   1 /*
   2  * Watchdog Driver Test Program
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <string.h>
   8 #include <unistd.h>
   9 #include <fcntl.h>
  10 #include <sys/ioctl.h>
  11 #include <linux/types.h>
  12 #include <linux/watchdog.h>
  13
  14 int fd;
  15
  16 /*
  17  * This function simply sends an IOCTL to the driver, which in turn ticks
  18  * the PC Watchdog card to reset its internal timer so it doesn't trigger
  19  * a computer reset.
  20  */
  21 static void keep_alive(void)
  22 {
  23     int dummy;
  24
  25     ioctl(fd, WDIOC_KEEPALIVE, &dummy);
  26 }
  27
  28 /*
  29  * The main program.  Run the program with "-d" to disable the card,
  30  * or "-e" to enable the card.
  31  */
  32 int main(int argc, char *argv[])
  33 {
  34     int flags;
  35
  36     fd = open("/dev/watchdog", O_WRONLY);
  37
  38     if (fd == -1) {
  39         fprintf(stderr, "Watchdog device not enabled.\n");
  40         fflush(stderr);
  41         exit(-1);
  42     }
  43
  44     if (argc > 1) {
  45         if (!strncasecmp(argv[1], "-d", 2)) {
  46             flags = WDIOS_DISABLECARD;
  47             ioctl(fd, WDIOC_SETOPTIONS, &flags);
  48             fprintf(stderr, "Watchdog card disabled.\n");
  49             fflush(stderr);
  50             exit(0);
  51         } else if (!strncasecmp(argv[1], "-e", 2)) {
  52             flags = WDIOS_ENABLECARD;
  53             ioctl(fd, WDIOC_SETOPTIONS, &flags);
  54             fprintf(stderr, "Watchdog card enabled.\n");
  55             fflush(stderr);
  56             exit(0);
  57         } else {
  58             fprintf(stderr, "-d to disable, -e to enable.\n");
  59             fprintf(stderr, "run by itself to tick the card.\n");
  60             fflush(stderr);
  61             exit(0);
  62         }
  63     } else {
  64         fprintf(stderr, "Watchdog Ticking Away!\n");
  65         fflush(stderr);
  66     }
  67
  68     while(1) {
  69         keep_alive();
  70         sleep(1);
  71     }
  72 }