Correctly release glib mainloop and gsource, to avoid memory leaks

Signed-off-by: Michele Calgaro <michele.calgaro@yahoo.it>
(cherry picked from commit 08a71c8f8d)

src/kernel/qeventloop_glib_p.h

@@ -116,6 +116,7 @@ public:
 
 	// main context
 	GMainContext *ctx;
+	GMainLoop *mainloop;
 	bool ctx_is_default;
 };
 

src/kernel/qeventloop_unix_glib.cpp

@@ -439,8 +439,10 @@ TQEventLoopPrivate::TQEventLoopPrivate() {
 	x_gPollFD.events = 0;
 	x_gPollFD.revents = 0;
 #endif // TQ_WS_X11
+	gSource = nullptr;
 	singletoolkit = TRUE;
-	ctx = 0;
+	ctx = nullptr;
+	mainloop = nullptr;
 	ctx_is_default = false;
 	reset();
 }

src/kernel/qeventloop_x11_glib.cpp

@@ -226,7 +226,7 @@ void TQEventLoop::init()
 	printf("inside init(1)\n");
 #endif
 
-	g_main_loop_new (d->ctx, 1);
+	d->mainloop = g_main_loop_new (d->ctx, 1);
 	g_source_attach( (GSource*)qtGSource, d->ctx );
 	d->gSource = (GSource*)qtGSource;
 
@@ -258,10 +258,22 @@ void TQEventLoop::cleanup()
 	// cleanup the X11 parts of the event loop
 	d->xfd = -1;
 
+	// stop polling the GSource
+	g_source_remove_poll(d->gSource, &d->threadPipe_gPollFD);
+	g_source_remove_poll(d->gSource, &d->x_gPollFD);
+	g_source_destroy(d->gSource);
+
+	// unref the main loop
+	g_main_loop_unref(d->mainloop);
+	d->mainloop = nullptr;
+
+	// unref the gsource
+	g_source_unref(d->gSource);
+	d->gSource = nullptr;
+
 	// unref the main context
 	g_main_context_unref(d->ctx);
-
-	// todo: destroy gsource
+	d->ctx = nullptr;
 }
 
 bool TQEventLoop::processEvents( ProcessEventsFlags flags )