Add EngineBase, a pure virtual public interface for the engine.

git-svn-id: http://svn.drobilla.net/lad/trunk/ingen@3155 a436a847-0d15-0410-975c-d299462d15a1

9 files changed, 96 insertions, 24 deletions

diff --git a/include/ingen/EngineBase.hpp b/include/ingen/EngineBase.hpp
new file mode 100644
index 00000000..cf3a2e97
--- /dev/null
+++ b/include/ingen/EngineBase.hpp
@@ -0,0 +1,67 @@
+/* This file is part of Ingen.
+ * Copyright 2007-2011 David Robillard <http://drobilla.net>
+ *
+ * Ingen 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.
+ *
+ * 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 General Public License for 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.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef INGEN_ENGINE_BASE_HPP
+#define INGEN_ENGINE_BASE_HPP
+
+#include "raul/SharedPtr.hpp"
+
+namespace Raul { class Maid; }
+
+namespace Ingen {
+
+namespace Shared { class World; }
+
+/**
+   The engine which executes the process graph.
+
+   @ingroup interface
+*/
+class EngineBase
+{
+public:
+	virtual ~EngineBase() {}
+
+	virtual bool activate() = 0;
+
+	virtual void deactivate() = 0;
+
+	/**
+	   Indicate that a quit is desired
+
+	   This function simply sets a flag which affects the return value of
+	   main_iteration, it does not actually force the engine to stop running or
+	   block.  The code driving the engine is responsible for stopping and
+	   cleaning up when main_iteration returns false.
+	*/
+	virtual void quit() = 0;
+
+	/**
+	   Run a single iteration of the main context.
+
+	   The main context post-processes events and performs housekeeping duties
+	   like collecting garbage.  This should be called regularly, e.g. a few
+	   times per second.  The return value indicates whether execution should
+	   continue; i.e. if false is returned, a quit has been requested and the
+	   caller should cease calling main_iteration() and stop the engine.
+	*/
+	virtual bool main_iteration() = 0;
+};
+
+} // namespace Ingen
+
+#endif // INGEN_ENGINE_BASE_HPP
diff --git a/src/engine/Engine.hpp b/src/engine/Engine.hpp
index e1854a8b..c9e9229e 100644
--- a/src/engine/Engine.hpp
+++ b/src/engine/Engine.hpp
@@ -25,8 +25,7 @@
 
 #include "raul/SharedPtr.hpp"
 
-#include "ingen/PortType.hpp"
-#include "ingen/EventType.hpp"
+#include "ingen/EngineBase.hpp"
 
 namespace Raul { class Maid; }
 
@@ -54,7 +53,7 @@ class ProcessContext;
 
    @ingroup engine
 */
-class Engine : public boost::noncopyable
+class Engine : public boost::noncopyable, public EngineBase
 {
 public:
 	explicit Engine(Ingen::Shared::World* world);
diff --git a/src/engine/LV2RequestRunFeature.hpp b/src/engine/LV2RequestRunFeature.hpp
index 9f35d506..6d6b66b3 100644
--- a/src/engine/LV2RequestRunFeature.hpp
+++ b/src/engine/LV2RequestRunFeature.hpp
@@ -48,9 +48,10 @@ struct RequestRunFeature : public Shared::LV2Features::Feature {
 		if (!data->world->local_engine())
 			return;
 
-		data->world->local_engine()->message_context()->run(
+		Engine* engine = (Engine*)data->world->local_engine().get();
+		engine->message_context()->run(
 			dynamic_cast<NodeImpl*>(data->node),
-			data->world->local_engine()->driver()->frame_time());
+			engine->driver()->frame_time());
 	}
 
 	static void delete_feature(LV2_Feature* feature) {
diff --git a/src/engine/ingen_jack.cpp b/src/engine/ingen_jack.cpp
index 93119bd8..e8645cb9 100644
--- a/src/engine/ingen_jack.cpp
+++ b/src/engine/ingen_jack.cpp
@@ -25,10 +25,11 @@ using namespace Ingen;
 
 struct IngenJackModule : public Ingen::Shared::Module {
 	void load(Ingen::Shared::World* world) {
-		Ingen::JackDriver* driver = new Ingen::JackDriver(*world->local_engine().get());
+		Ingen::JackDriver* driver = new Ingen::JackDriver(
+			*(Engine*)world->local_engine().get());
 		driver->attach(world->conf()->option("jack-server").get_string(),
 				world->conf()->option("jack-client").get_string(), NULL);
-		world->local_engine()->set_driver(SharedPtr<Driver>(driver));
+		((Engine*)world->local_engine().get())->set_driver(SharedPtr<Driver>(driver));
 	}
 };
 
diff --git a/src/engine/ingen_lv2.cpp b/src/engine/ingen_lv2.cpp
index a6f178ff..69daa7ae 100644
--- a/src/engine/ingen_lv2.cpp
+++ b/src/engine/ingen_lv2.cpp
@@ -267,11 +267,12 @@ ingen_instantiate(const LV2_Descriptor*    descriptor,
 	plugin->world->set_local_engine(engine);
 
 	SharedPtr<QueuedEngineInterface> interface(
-		new Ingen::QueuedEngineInterface(*plugin->world->local_engine(),
-		                                 event_queue_size));
+		new Ingen::QueuedEngineInterface(
+			*engine.get(),
+			event_queue_size));
 
 	plugin->world->set_engine(interface);
-	plugin->world->local_engine()->add_event_source(interface);
+	engine->add_event_source(interface);
 
 	Raul::Thread::get().set_context(THREAD_PRE_PROCESS);
 	ThreadManager::single_threaded = true;
@@ -309,9 +310,9 @@ ingen_instantiate(const LV2_Descriptor*    descriptor,
 static void
 ingen_connect_port(LV2_Handle instance, uint32_t port, void* data)
 {
-	IngenPlugin*             me     = (IngenPlugin*)instance;
-	SharedPtr<Ingen::Engine> engine = me->world->local_engine();
-	Ingen::LV2::LV2Driver*   driver = (Ingen::LV2::LV2Driver*)engine->driver();
+	IngenPlugin*           me     = (IngenPlugin*)instance;
+	Ingen::Engine*         engine = (Ingen::Engine*)me->world->local_engine().get();
+	Ingen::LV2::LV2Driver* driver = (Ingen::LV2::LV2Driver*)engine->driver();
 	if (port < driver->ports().size()) {
 		driver->ports().at(port)->set_buffer(data);
 		assert(driver->ports().at(port)->patch_port()->index() == port);
@@ -330,10 +331,11 @@ ingen_activate(LV2_Handle instance)
 static void
 ingen_run(LV2_Handle instance, uint32_t sample_count)
 {
-	IngenPlugin* me = (IngenPlugin*)instance;
+	IngenPlugin*   me     = (IngenPlugin*)instance;
+	Ingen::Engine* engine = (Ingen::Engine*)me->world->local_engine().get();
 	// FIXME: don't do this every call
 	Raul::Thread::get().set_context(Ingen::THREAD_PROCESS);
-	((Ingen::LV2::LV2Driver*)me->world->local_engine()->driver())->run(sample_count);
+	((Ingen::LV2::LV2Driver*)engine->driver())->run(sample_count);
 }
 
 static void
diff --git a/src/engine/ingen_osc.cpp b/src/engine/ingen_osc.cpp
index 5e75b756..0a2d6768 100644
--- a/src/engine/ingen_osc.cpp
+++ b/src/engine/ingen_osc.cpp
@@ -27,10 +27,11 @@ using namespace Ingen;
 struct IngenOSCModule : public Ingen::Shared::Module {
 	void load(Ingen::Shared::World* world) {
 		SharedPtr<OSCEngineReceiver> interface(
-				new Ingen::OSCEngineReceiver(*world->local_engine().get(),
+				new Ingen::OSCEngineReceiver(
+					*(Engine*)world->local_engine().get(),
 					event_queue_size,
 					world->conf()->option("engine-port").get_int32()));
-		world->local_engine()->add_event_source(interface);
+		((Engine*)world->local_engine().get())->add_event_source(interface);
 	}
 };
 
diff --git a/src/gui/ConnectWindow.cpp b/src/gui/ConnectWindow.cpp
index 9f466e29..8c5a654a 100644
--- a/src/gui/ConnectWindow.cpp
+++ b/src/gui/ConnectWindow.cpp
@@ -246,7 +246,7 @@ ConnectWindow::connect(bool existing)
 
 		SharedPtr<SigClientInterface> client(new SigClientInterface());
 
-		if (!world->local_engine()->driver())
+		if (!((Engine*)world->local_engine().get())->driver())
 			world->load("ingen_jack");
 
 		world->local_engine()->activate();
diff --git a/src/shared/World.cpp b/src/shared/World.cpp
index f869dc33..38c08340 100644
--- a/src/shared/World.cpp
+++ b/src/shared/World.cpp
@@ -25,6 +25,7 @@
 #endif
 #include "raul/log.hpp"
 #include "sord/sordmm.hpp"
+#include "ingen/EngineBase.hpp"
 #include "shared/runtime_paths.hpp"
 #include "shared/LV2Features.hpp"
 #include "shared/LV2URIMap.hpp"
@@ -172,7 +173,7 @@ public:
 	Sord::World*                         rdf_world;
 	SharedPtr<LV2URIMap>                 uris;
     SharedPtr<EngineInterface>           engine;
-	SharedPtr<Engine>                    local_engine;
+	SharedPtr<EngineBase>                local_engine;
     SharedPtr<Serialisation::Serialiser> serialiser;
     SharedPtr<Serialisation::Parser>     parser;
     SharedPtr<Store>                     store;
@@ -191,7 +192,7 @@ World::~World()
 	delete _impl;
 }
 
-void World::set_local_engine(SharedPtr<Engine> e)                  { _impl->local_engine = e; }
+void World::set_local_engine(SharedPtr<EngineBase> e)              { _impl->local_engine = e; }
 void World::set_engine(SharedPtr<EngineInterface> e)               { _impl->engine = e; }
 void World::set_serialiser(SharedPtr<Serialisation::Serialiser> s) { _impl->serialiser = s; }
 void World::set_parser(SharedPtr<Serialisation::Parser> p)         { _impl->parser = p; }
@@ -200,7 +201,7 @@ void World::set_conf(Raul::Configuration* c)                       { _impl->conf
 
 int&                                 World::argc()         { return _impl->argc; }
 char**&                              World::argv()         { return _impl->argv; }
-SharedPtr<Engine>                    World::local_engine() { return _impl->local_engine; }
+SharedPtr<EngineBase>                World::local_engine() { return _impl->local_engine; }
 SharedPtr<EngineInterface>           World::engine()       { return _impl->engine; }
 SharedPtr<Serialisation::Serialiser> World::serialiser()   { return _impl->serialiser; }
 SharedPtr<Serialisation::Parser>     World::parser()       { return _impl->parser; }
diff --git a/src/shared/World.hpp b/src/shared/World.hpp
index 233ae83a..4a07d4f6 100644
--- a/src/shared/World.hpp
+++ b/src/shared/World.hpp
@@ -35,7 +35,7 @@ namespace Sord { class World; }
 
 namespace Ingen {
 
-class Engine;
+class EngineBase;
 
 namespace Serialisation { class Serialiser; class Parser; }
 
@@ -76,13 +76,13 @@ public:
 	virtual bool run(const std::string& mime_type,
 	                 const std::string& filename);
 
-	virtual void set_local_engine(SharedPtr<Engine> e);
+	virtual void set_local_engine(SharedPtr<EngineBase> e);
 	virtual void set_engine(SharedPtr<EngineInterface> e);
 	virtual void set_serialiser(SharedPtr<Serialisation::Serialiser> s);
 	virtual void set_parser(SharedPtr<Serialisation::Parser> p);
 	virtual void set_store(SharedPtr<Store> s);
 
-	virtual SharedPtr<Engine>                    local_engine();
+	virtual SharedPtr<EngineBase>                local_engine();
 	virtual SharedPtr<EngineInterface>           engine();
 	virtual SharedPtr<Serialisation::Serialiser> serialiser();
 	virtual SharedPtr<Serialisation::Parser>     parser();