From 01463d7b28a6666919ab432071ab332df5ccc82d Mon Sep 17 00:00:00 2001
From: Georg Hopp <georg@steffers.org>
Date: Wed, 27 Aug 2014 18:36:01 +0100
Subject: [PATCH] add finalize for event subjects. This results in an delete of
 the subject as soon as the last event is done and prevents emitting new
 events. Force heartbeat to be done and don't queue it.

---
 include/tr/event_subject.h      |  3 +++
 src/event.c                     |  8 +++++++-
 src/event_dispatcher_start.c    | 14 +++++---------
 src/event_handler_issue_event.c |  6 ++++--
 src/event_subject_emit.c        |  6 +++---
 5 files changed, 22 insertions(+), 15 deletions(-)

diff --git a/include/tr/event_subject.h b/include/tr/event_subject.h
index 1b1c9bb..2b8e65c 100644
--- a/include/tr/event_subject.h
+++ b/include/tr/event_subject.h
@@ -29,6 +29,7 @@
 #include "trbase.h"
 
 TR_CLASS(TR_EventSubject) {
+	int    fin;
 	size_t emitted;
 };
 TR_INSTANCE_INIT(TR_EventSubject);
@@ -55,6 +56,8 @@ TR_CLASSVARS_DECL(TR_EventSubject) {
 intptr_t TR__eventSubjectId(TR_class_ptr, size_t);
 TR_Event TR_eventSubjectEmit(TR_EventSubject, int, void *);
 
+#define TR_eventSubjectFinalize(es) ((es)->fin = TRUE)
+
 #endif // __TR_EVENT_SUBJECT_H__
 
 // vim: set ts=4 sw=4:
diff --git a/src/event.c b/src/event.c
index c140c52..458b452 100644
--- a/src/event.c
+++ b/src/event.c
@@ -45,7 +45,13 @@ static void eventDtor(void * _this)
 {
 	TR_Event this = _this;
 
-	this->subject->emitted--;
+	this->subject->emitted =
+		this->subject->emitted == 0 
+		? 0 : this->subject->emitted - 1;
+
+	if (0 == this->subject->emitted && this->subject->fin) {
+		TR_delete(this->subject);
+	}
 }
 
 TR_INIT_IFACE(TR_Class, eventCtor, eventDtor, NULL);
diff --git a/src/event_dispatcher_start.c b/src/event_dispatcher_start.c
index 0ad631d..8a1f927 100644
--- a/src/event_dispatcher_start.c
+++ b/src/event_dispatcher_start.c
@@ -49,15 +49,11 @@ TR_eventDispatcherStart(TR_EventDispatcher this)
 
 		if (this->nextbeat && this->nextbeat <= now) {
 			this->nextbeat += this->heartbeat;
-			TR_eventDispatcherEnqueueEvent(
-					this, 
-					TR_eventSubjectEmit(
-						(TR_EventSubject)this,
-						TR_DISPATCHER_EVENT_HEARTBEAT,
-						NULL));
-		}
-
-		if (TR_queueEmpty(this->events) || this->nextpoll <= now) {
+			event = TR_eventSubjectEmit(
+					(TR_EventSubject)this,
+					TR_DISPATCHER_EVENT_HEARTBEAT,
+					NULL);
+		} else if (TR_queueEmpty(this->events) || this->nextpoll <= now) {
 			int evtid = TR_EVD_CLIENT == this->mode
 				? TR_DISPATCHER_EVENT_USER_WAIT
 				: TR_DISPATCHER_EVENT_DATA_WAIT;
diff --git a/src/event_handler_issue_event.c b/src/event_handler_issue_event.c
index 59afbee..30eef98 100644
--- a/src/event_handler_issue_event.c
+++ b/src/event_handler_issue_event.c
@@ -30,8 +30,10 @@ TR_eventHandlerIssueEvent(TR_EventHandler this, TR_Event event)
 {
 	int      i;
 
-	for (i=0; i<this->ndispatcher; i++) {
-		TR_eventDispatcherEnqueueEvent(this->dispatcher[i], event);
+	if (event) {
+		for (i=0; i<this->ndispatcher; i++) {
+			TR_eventDispatcherEnqueueEvent(this->dispatcher[i], event);
+		}
 	}
 }
 
diff --git a/src/event_subject_emit.c b/src/event_subject_emit.c
index 283699f..4405380 100644
--- a/src/event_subject_emit.c
+++ b/src/event_subject_emit.c
@@ -20,6 +20,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stdio.h>
 #include <stdint.h>
 
 #include "tr/event.h"
@@ -33,13 +34,12 @@ TR_eventSubjectEmit(TR_EventSubject this, int idx, void * data)
 	intptr_t id    = TR_eventSubjectGetId(this, idx);
 	TR_Event event = NULL;
 
-	if (id) {
+	if (id && ! this->fin) {
 		event = TR_new(TR_Event, id, this);
 		TR_eventSetData(event, data);
+		this->emitted++;
 	}
 
-	this->emitted++;
-
 	return event;
 }