4 files changed, 26 insertions, 17 deletions
diff --git a/src/server/Engine.cpp b/src/server/Engine.cpp
index eeb28e5a..c7fef892 100644
--- a/src/server/Engine.cpp
+++ b/src/server/Engine.cpp
@@ -258,7 +258,7 @@ Engine::activate()
 void
 Engine::deactivate()
 {
-	_pre_processor->stop();
+	_pre_processor->join();
 
 	if (_driver) {
 		_driver->deactivate();
diff --git a/src/server/PreProcessor.cpp b/src/server/PreProcessor.cpp
index 9db13fd1..13746113 100644
--- a/src/server/PreProcessor.cpp
+++ b/src/server/PreProcessor.cpp
@@ -26,14 +26,14 @@ namespace Ingen {
 namespace Server {
 
 PreProcessor::PreProcessor()
-	: Raul::Slave("PreProcessor")
+	: Raul::Thread("PreProcessor")
+	, _sem(0)
 {
 	start();
 }
 
 PreProcessor::~PreProcessor()
 {
-	stop();
 }
 
 void
@@ -61,7 +61,7 @@ PreProcessor::event(Event* const ev)
 		_prepared_back = ev;
 	}
 
-	whip();
+	_sem.post();
 }
 
 unsigned
@@ -110,18 +110,21 @@ PreProcessor::process(ProcessContext& context, PostProcessor& dest, bool limit)
 
 /** Pre-process a single event */
 void
-PreProcessor::_whipped()
+PreProcessor::_run()
 {
 	ThreadManager::set_flag(THREAD_PRE_PROCESS);
-	Event* ev = _prepared_back.get();
-	if (!ev)
-		return;
+	while (_sem.wait() && !_exit_flag) {
+		Event* const ev = _prepared_back.get();
+		if (!ev) {
+			return;
+		}
 
-	assert(!ev->is_prepared());
-	ev->pre_process();
-	assert(ev->is_prepared());
+		assert(!ev->is_prepared());
+		ev->pre_process();
+		assert(ev->is_prepared());
 
-	_prepared_back = (Event*)ev->next();
+		_prepared_back = (Event*)ev->next();
+	}
 }
 
 } // namespace Server
diff --git a/src/server/PreProcessor.hpp b/src/server/PreProcessor.hpp
index fd886139..9b7fbd44 100644
--- a/src/server/PreProcessor.hpp
+++ b/src/server/PreProcessor.hpp
@@ -20,7 +20,8 @@
 #include <glibmm/thread.h>
 
 #include "raul/AtomicPtr.hpp"
-#include "raul/Slave.hpp"
+#include "raul/Semaphore.hpp"
+#include "raul/Thread.hpp"
 
 namespace Ingen {
 namespace Server {
@@ -29,13 +30,18 @@ class Event;
 class PostProcessor;
 class ProcessContext;
 
-class PreProcessor : public Raul::Slave
+class PreProcessor : public Raul::Thread
 {
 public:
 	explicit PreProcessor();
 
 	~PreProcessor();
 
+	virtual void join() {
+		_exit_flag = true;
+		_sem.post();
+	}
+
 	/** Return true iff no events are enqueued. */
 	inline bool empty() const { return !_head.get(); }
 
@@ -52,10 +58,11 @@ public:
 	                 bool            limit = true);
 
 protected:
-	virtual void _whipped();  ///< Prepare 1 event
+	virtual void _run();
 
 private:
 	Glib::Mutex            _mutex;
+	Raul::Semaphore        _sem;
 	Raul::AtomicPtr<Event> _head;
 	Raul::AtomicPtr<Event> _prepared_back;
 	Raul::AtomicPtr<Event> _tail;
diff --git a/src/server/Worker.cpp b/src/server/Worker.cpp
index d17482bf..2c1c51a0 100644
--- a/src/server/Worker.cpp
+++ b/src/server/Worker.cpp
@@ -119,8 +119,7 @@ Worker::~Worker()
 void
 Worker::_run()
 {
-	while (!_exit_flag) {
-		_sem.wait();
+	while (_sem.wait() && !_exit_flag) {
 		MessageHeader msg;
 		if (_requests.read_space() > sizeof(msg)) {
 			if (_requests.read(sizeof(msg), &msg) != sizeof(msg)) {