+/*
+ Copyright (C) 2012 Paul Davis
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
#include "pbd/event_loop.h"
+#include "pbd/stacktrace.h"
using namespace PBD;
-
-Glib::StaticPrivate<EventLoop> EventLoop::thread_event_loop;
+using namespace std;
static void do_not_delete_the_loop_pointer (void*) { }
-EventLoop*
+Glib::Threads::Private<EventLoop> EventLoop::thread_event_loop (do_not_delete_the_loop_pointer);
+
+EventLoop*
EventLoop::get_event_loop_for_thread() {
return thread_event_loop.get ();
}
-void
-EventLoop::set_event_loop_for_thread (EventLoop* loop)
+void
+EventLoop::set_event_loop_for_thread (EventLoop* loop)
+{
+ thread_event_loop.set (loop);
+}
+
+void*
+EventLoop::invalidate_request (void* data)
{
- thread_event_loop.set (loop, do_not_delete_the_loop_pointer);
+ InvalidationRecord* ir = (InvalidationRecord*) data;
+
+ /* Some of the requests queued with an EventLoop may involve functors
+ * that make method calls to objects whose lifetime is shorter
+ * than the EventLoop's. We do not want to make those calls if the
+ * object involve has been destroyed. To prevent this, we
+ * provide a way to invalidate those requests when the object is
+ * destroyed.
+ *
+ * An object was passed to __invalidator() which added a callback to
+ * EventLoop::invalidate_request() to its "notify when destroyed"
+ * list. __invalidator() returned an InvalidationRecord that has been
+ * to passed to this function as data.
+ *
+ * The object is currently being destroyed and so we want to
+ * mark all requests involving this object that are queued with
+ * any EventLoop as invalid.
+ *
+ * As of April 2012, we are usign sigc::trackable as the base object
+ * used to queue calls to ::invalidate_request() to be made upon
+ * destruction, via its ::add_destroy_notify_callback() API. This is
+ * not necessarily ideal, but it is very close to precisely what we
+ * want, and many of the objects we want to do this with already
+ * inherit (indirectly) from sigc::trackable.
+ */
+
+ if (ir->event_loop) {
+ Glib::Threads::Mutex::Lock lm (ir->event_loop->slot_invalidation_mutex());
+ for (list<BaseRequestObject*>::iterator i = ir->requests.begin(); i != ir->requests.end(); ++i) {
+ (*i)->valid = false;
+ (*i)->invalidation = 0;
+ }
+ delete ir;
+ }
+
+ return 0;
}