1 files changed, 37 insertions, 0 deletions
diff --git a/src/or/periodic.h b/src/or/periodic.h
new file mode 100644
index 0000000000..021bb4ef5c
--- /dev/null
+++ b/src/or/periodic.h
@@ -0,0 +1,37 @@
+/* Copyright (c) 2015-2016, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_PERIODIC_H
+#define TOR_PERIODIC_H
+
+#define PERIODIC_EVENT_NO_UPDATE (-1)
+
+/** Callback function for a periodic event to take action.  The return value
+* influences the next time the function will get called.  Return
+* PERIODIC_EVENT_NO_UPDATE to not update <b>last_action_time</b> and be polled
+* again in the next second. If a positive value is returned it will update the
+* interval time. */
+typedef int (*periodic_event_helper_t)(time_t now,
+                                      const or_options_t *options);
+
+struct event;
+
+/** A single item for the periodic-events-function table. */
+typedef struct periodic_event_item_t {
+  periodic_event_helper_t fn; /**< The function to run the event */
+  time_t last_action_time; /**< The last time the function did something */
+  struct event *ev; /**< Libevent callback we're using to implement this */
+  const char *name; /**< Name of the function -- for debug */
+} periodic_event_item_t;
+
+/** events will get their interval from first execution */
+#define PERIODIC_EVENT(fn) { fn##_callback, 0, NULL, #fn }
+#define END_OF_PERIODIC_EVENTS { NULL, 0, NULL, NULL }
+
+void periodic_event_launch(periodic_event_item_t *event);
+void periodic_event_setup(periodic_event_item_t *event);
+void periodic_event_destroy(periodic_event_item_t *event);
+void periodic_event_reschedule(periodic_event_item_t *event);
+
+#endif
+