5 files changed, 58 insertions, 7 deletions
diff --git a/src/engine/JackDriver.cpp b/src/engine/JackDriver.cpp
index fefa4d2..6dc2153 100644
--- a/src/engine/JackDriver.cpp
+++ b/src/engine/JackDriver.cpp
@@ -60,11 +60,15 @@ JackDriver::attach(const std::string& client_name)
 void
 JackDriver::detach()
 {
-	jack_port_unregister(jack_client(), _input_port);
-	jack_port_unregister(jack_client(), _output_port);
-	_input_port = NULL;
-	_output_port = NULL;
-
+	if (_input_port) {
+		jack_port_unregister(jack_client(), _input_port);
+		_input_port = NULL;
+	}
+	
+	if (_output_port) {
+		jack_port_unregister(jack_client(), _output_port);
+		_output_port = NULL;
+	}
 	Raul::JackDriver::detach();
 }
 
diff --git a/src/engine/Machine.cpp b/src/engine/Machine.cpp
index dbb212c..142ea37 100644
--- a/src/engine/Machine.cpp
+++ b/src/engine/Machine.cpp
@@ -197,5 +197,29 @@ Machine::learn(SharedPtr<LearnRequest> learn)
 }
 
 
+void
+Machine::write_state(Raul::RDFWriter& writer)
+{
+	using Raul::RdfId;
+
+	writer.add_prefix("machina", "http://drobilla.net/ns/machina");
+
+	writer.write(RdfId(RdfId::RESOURCE, ""),
+			RdfId(RdfId::RESOURCE, "rdf:type"),
+			RdfId(RdfId::RESOURCE, "machina:Machine"));
+
+	for (Nodes::const_iterator n = _nodes.begin(); n != _nodes.end(); ++n) {
+		if ( ! (*n)->id() )
+			(*n)->set_id(writer.blank_id());
+
+		(*n)->write_state(writer);
+
+		writer.write(RdfId(RdfId::RESOURCE, ""),
+				RdfId(RdfId::RESOURCE, "machina:node"),
+				(*n)->id());
+	}
+} 
+
+
 } // namespace Machina
 
diff --git a/src/engine/Node.cpp b/src/engine/Node.cpp
index 59af04e..c0e0ce6 100644
--- a/src/engine/Node.cpp
+++ b/src/engine/Node.cpp
@@ -16,6 +16,7 @@
  */
 
 #include <cassert>
+#include <raul/RDFWriter.h>
 #include "machina/Node.hpp"
 #include "machina/Edge.hpp"
 
@@ -99,5 +100,21 @@ Node::remove_outgoing_edge(SharedPtr<Edge> edge)
 }
 
 
+void
+Node::write_state(Raul::RDFWriter& writer)
+{
+	using Raul::RdfId;
+	
+	writer.write(_id,
+			RdfId(RdfId::RESOURCE, "rdf:type"),
+			RdfId(RdfId::RESOURCE, "machina:Node"));
+
+	writer.write(_id,
+	             RdfId(RdfId::RESOURCE, "machina:duration"),
+				 Raul::Atom((int)_duration));
+}
+
+
+
 } // namespace Machina
 
diff --git a/src/engine/machina/Machine.hpp b/src/engine/machina/Machine.hpp
index b53f55c..3e63530 100644
--- a/src/engine/machina/Machine.hpp
+++ b/src/engine/machina/Machine.hpp
@@ -20,6 +20,7 @@
 
 #include <raul/SharedPtr.h>
 #include <raul/List.h>
+#include <raul/RDFWriter.h> 
 #include "types.hpp"
 #include "LearnRequest.hpp"
 #include "Node.hpp"
@@ -27,7 +28,7 @@
 namespace Machina {
 
 
-class Machine {
+class Machine : public Raul::Stateful {
 public:
 	Machine();
 	~Machine();
@@ -42,6 +43,8 @@ public:
 	void add_node(SharedPtr<Node> node);
 	void learn(SharedPtr<LearnRequest> learn);
 
+	void write_state(Raul::RDFWriter& writer);
+
 	// Audio context
 	void            reset();
 	FrameCount      run(FrameCount nframes);
diff --git a/src/engine/machina/Node.hpp b/src/engine/machina/Node.hpp
index 243773f..10d4ed4 100644
--- a/src/engine/machina/Node.hpp
+++ b/src/engine/machina/Node.hpp
@@ -21,6 +21,7 @@
 #include <boost/utility.hpp>
 #include <raul/SharedPtr.h>
 #include <raul/List.h>
+#include <raul/Stateful.h>
 #include "types.hpp"
 #include "Action.hpp"
 
@@ -37,7 +38,7 @@ class Edge;
  * Initial nodes do not have enter actions (since they are entered at
  * an undefined point in time <= 0).
  */
-class Node : public boost::noncopyable {
+class Node : public Raul::Stateful, public boost::noncopyable {
 public:
 	typedef std::string ID;
 
@@ -55,6 +56,8 @@ public:
 	void add_outgoing_edge(SharedPtr<Edge> edge);
 	void remove_outgoing_edge(SharedPtr<Edge> edge);
 
+	void write_state(Raul::RDFWriter& writer);
+
 	bool       is_initial() const         { return _is_initial; }
 	void       set_initial(bool i)        { _is_initial = i; }
 	bool       is_active() const          { return _is_active; }