Simply event interface design and make only one pre-process thread.

This makes event pre-processing actually safe for multiple interfaces since multiple events will never be pre-processed simultaneously and the pre-process order is definitely the same as the execute order.


git-svn-id: http://svn.drobilla.net/lad/trunk/ingen@4323 a436a847-0d15-0410-975c-d299462d15a1

1 files changed, 67 insertions, 0 deletions

diff --git a/src/server/PreProcessor.hpp b/src/server/PreProcessor.hpp
new file mode 100644
index 00000000..4fd1c91e
--- /dev/null
+++ b/src/server/PreProcessor.hpp
@@ -0,0 +1,67 @@
+/*
+  This file is part of Ingen.
+  Copyright 2007-2012 David Robillard <http://drobilla.net/>
+
+  Ingen is free software: you can redistribute it and/or modify it under the
+  terms of the GNU Affero General Public License as published by the Free
+  Software Foundation, either version 3 of the License, or any later version.
+
+  Ingen 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 Affero General Public License for details.
+
+  You should have received a copy of the GNU Affero General Public License
+  along with Ingen.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef INGEN_ENGINE_PREPROCESSOR_HPP
+#define INGEN_ENGINE_PREPROCESSOR_HPP
+
+#include <glibmm/thread.h>
+
+#include "raul/Slave.hpp"
+
+namespace Ingen {
+namespace Server {
+
+class Event;
+class PostProcessor;
+class ProcessContext;
+
+class PreProcessor : public Raul::Slave
+{
+public:
+	explicit PreProcessor();
+
+	~PreProcessor();
+
+	/** Return true iff no events are enqueued. */
+	inline bool empty() const { return !_head.get(); }
+
+	/** Enqueue an event.
+	 * This is safe to call from any non-realtime thread (it locks).
+	 */
+	void event(Event* ev);
+
+	/** Process events for a cycle.
+	 * @return False iff this source is finished and should be removed.
+	 */
+	bool process(PostProcessor&  dest,
+	             ProcessContext& context,
+	             bool            limit = true);
+
+protected:
+	virtual void _whipped();  ///< Prepare 1 event
+
+private:
+	Glib::Mutex            _mutex;
+	Raul::AtomicPtr<Event> _head;
+	Raul::AtomicPtr<Event> _prepared_back;
+	Raul::AtomicPtr<Event> _tail;
+};
+
+} // namespace Server
+} // namespace Ingen
+
+#endif // INGEN_ENGINE_PREPROCESSOR_HPP
+