watchdog.h

#ifndef RS_WATCHDOG_H
#define RS_WATCHDOG_H

#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <unistd.h> //Header file for sleep(). man 3 sleep for details.

#define RS_SLEEP(x) sleep(x)

typedef void (*WDT_CALLBACK)(void *);

// function to receive current timestamp
// -------------------------------------
long long current_timestamp();

// represents each entry in TaskList
// -----------------------------------
typedef struct taskListEntry {
  struct taskListEntry *next;
  struct taskListEntry *prev;
  long long task_id;
  long long last_run;
  unsigned int timeout;
  WDT_CALLBACK callback;

} TaskListEntry;

// List to store tasks that are watched by dog
// -----------------------------------
typedef struct taskList {
  TaskListEntry *head;
  TaskListEntry *tail;
} TaskList;

// represent the Dog
// -----------------------------------
typedef struct Dog {
  TaskList t_list;
  long long sleep_time;

  // runs before the actual restart
  // can be used for a graceful restart
  WDT_CALLBACK callback;
  void *callback_arg;
} WatchDog;

static WatchDog watchdog;

void init_the_dog(long long sleep_time, WDT_CALLBACK cb);

// feed the dog to prevent it's fireup
// -----------------------------------
void feed_the_dog(pthread_t task_id);

// subscribe to watchdog
// -----------------------------------
void add_to_watchlist(pthread_t task_id, unsigned int timeout,
                      WDT_CALLBACK callback);

// The watchgod Task
// -----------------------------------
void *watchDog(void *args);

// Main Reset Function, when the dog gets Angry, this function will be called
// -----------------------------------
void fire_the_dog();

int is_exists(long long task_id);

#endif // RS_WATCHDOG_H