support for periodic timeouts

svn:r762

ChangeLog

@@ -87,6 +87,7 @@ Changes in current version:
  o introduce evbuffer_reserve_space() and evbuffer_commit_space() to make processing in filters more efficient.
  o reduce system calls for getting current time by caching it.
  o separate signal events from io events; making the code less complex.
+ o support for periodic timeouts
 	
 Changes in 1.4.0:
  o allow \r or \n individually to separate HTTP headers instead of the standard "\r\n"; from Charles Kerr.

event.c

@@ -137,6 +137,7 @@ static void	timeout_process(struct event_base *);
 static void	timeout_correct(struct event_base *, struct timeval *);
 
 static void	event_signal_closure(struct event_base *, struct event *ev);
+static void	event_periodic_closure(struct event_base *, struct event *ev);
 
 static void
 detect_monotonic(void)
@@ -362,6 +363,13 @@ event_haveevents(struct event_base *base)
 	return (base->event_count > 0);
 }
 
+static void
+event_periodic_closure(struct event_base *base, struct event *ev)
+{
+	event_add(ev, &ev->_ev.ev_periodic.tv_interval);
+	(*ev->ev_callback)((int)ev->ev_fd, ev->ev_res, ev->ev_arg);
+}
+
 static void
 event_signal_closure(struct event_base *base, struct event *ev)
 {
@@ -709,6 +717,16 @@ event_assign(struct event *ev, struct event_base *base, evutil_socket_t fd, shor
 		return (0);
 }
 
+void
+evperiodic_assign(struct event *ev, struct event_base *base,
+    struct timeval *tv, void (*cb)(evutil_socket_t, short, void *), void *arg)
+{
+	event_assign(ev, base, -1, EV_TIMEOUT, cb, arg);
+	
+	ev->_ev.ev_periodic.tv_interval = *tv;
+	ev->ev_closure = event_periodic_closure;
+}
+
 struct event *
 event_new(struct event_base *base, evutil_socket_t fd, short events, void (*cb)(evutil_socket_t, short, void *), void *arg)
 {

include/event2/event.h

@@ -184,6 +184,22 @@ int event_base_loopexit(struct event_base *, struct timeval *);
  */
 int event_base_loopbreak(struct event_base *);
 
+/**
+   Define a periodic timer.
+
+   Behaves like a timer only that it repeats at the specified interval.
+   To start this time, it needs to be added via event_add().
+
+   @param ev event struct to be modified
+   @param base the event base to which this event belongs
+   @param tv periodicity interval
+   @param cb callback function
+   @param arg argument that will be passed to the callback function
+*/
+
+void evperiodic_assign(struct event *ev, struct event_base *base,
+    struct timeval *tv, void (*cb)(int, short, void *), void *arg);
+
 /**
   Define a timer event.
 

include/event2/event_struct.h

@@ -104,6 +104,10 @@ struct event {
 			/* Allows deletes in callback */
 			short *ev_pncalls;
 		} ev_signal;
+
+		struct {
+			struct timeval tv_interval;
+		} ev_periodic;
 	} _ev;
 
 	short ev_events;

test/regress.c

@@ -432,6 +432,43 @@ test_simpletimeout(void)
 	cleanup_test();
 }
 
+static void
+periodic_timeout_cb(int fd, short event, void *arg)
+{
+	int *count = arg;
+
+	(*count)++;
+	if (*count > 5) {
+		test_ok = 1;
+		event_base_loopexit(global_base, NULL);
+	}
+}
+
+static void
+test_periodictimeout(void)
+{
+	struct timeval tv, tv_interval;
+	struct event ev;
+	int count = 0;
+
+	setup_test("Periodic timeout: ");
+
+	timerclear(&tv_interval);
+	tv_interval.tv_usec = 10000;
+
+	tv.tv_usec = 0;
+	tv.tv_sec = 0;
+	evperiodic_assign(&ev, global_base, &tv_interval,
+	    periodic_timeout_cb, &count);
+	event_add(&ev, &tv);
+
+	event_dispatch();
+
+	event_del(&ev);
+
+	cleanup_test();
+}
+
 #ifndef WIN32
 extern struct event_base *current_base;
 static void
@@ -2044,6 +2081,8 @@ main (int argc, char **argv)
 
         test_evutil_strtoll();
 
+	test_periodictimeout();
+
 	/* use the global event base and need to be called first */
 	test_priorities(1);
 	test_priorities(2);
@@ -2091,6 +2130,7 @@ main (int argc, char **argv)
 	test_combined();
 
 	test_simpletimeout();
+
 #ifndef WIN32
 	test_simplesignal();
 	test_immediatesignal();