3 files changed, 23 insertions, 16 deletions
diff --git a/backends/mutex/default/default-mutex.cpp b/backends/mutex/abstract-mutex.h
index e10e9e8ade..b5e0263c09 100644
--- a/backends/mutex/default/default-mutex.cpp
+++ b/backends/mutex/abstract-mutex.h
@@ -23,8 +23,19 @@
  *
  */
 
-#include "backends/mutex/default/default-mutex.h"
+#ifndef BACKENDS_MUTEX_ABSTRACT_H
+#define BACKENDS_MUTEX_ABSTRACT_H
 
-OSystem::MutexRef DefaultMutexManager::createMutex() {
-	return OSystem::MutexRef();
-}
+#include "common/system.h"
+#include "common/noncopyable.h"
+
+class MutexManager : Common::NonCopyable {
+public:
+	virtual OSystem::MutexRef createMutex() = 0;
+	virtual void lockMutex(OSystem::MutexRef mutex) = 0;
+	virtual void unlockMutex(OSystem::MutexRef mutex) = 0;
+	virtual void deleteMutex(OSystem::MutexRef mutex) = 0;
+};
+
+
+#endif
diff --git a/backends/mutex/default/default-mutex.h b/backends/mutex/null/null-mutex.h
index 44aa8ee20f..76bb595631 100644
--- a/backends/mutex/default/default-mutex.h
+++ b/backends/mutex/null/null-mutex.h
@@ -23,21 +23,17 @@
  *
  */
 
-#ifndef BACKENDS_MUTEX_DEFAULT_H
-#define BACKENDS_MUTEX_DEFAULT_H
+#ifndef BACKENDS_MUTEX_NULL_H
+#define BACKENDS_MUTEX_NULL_H
 
-#include "common/system.h"
-#include "common/noncopyable.h"
+#include "backends/mutex/abstract-mutex.h"
 
-class DefaultMutexManager : Common::NonCopyable {
+class NullMutexManager : MutexManager {
 public:
-	virtual ~DefaultMutexManager() {}
-
-	OSystem::MutexRef createMutex();
+	OSystem::MutexRef createMutex() { return OSystem::MutexRef(); }
 	void lockMutex(OSystem::MutexRef mutex) {}
 	void unlockMutex(OSystem::MutexRef mutex) {}
-	void deleteMutex(OSystem::MutexRef mutex);
+	void deleteMutex(OSystem::MutexRef mutex) {}
 };
 
-
 #endif
diff --git a/backends/mutex/sdl/sdl-mutex.h b/backends/mutex/sdl/sdl-mutex.h
index aad3032315..acd13a879d 100644
--- a/backends/mutex/sdl/sdl-mutex.h
+++ b/backends/mutex/sdl/sdl-mutex.h
@@ -26,9 +26,9 @@
 #ifndef BACKENDS_MUTEX_SDL_H
 #define BACKENDS_MUTEX_SDL_H
 
-#include "backends/mutex/default/default-mutex.h"
+#include "backends/mutex/abstract-mutex.h"
 
-class SdlMutexManager : public DefaultMutexManager {
+class SdlMutexManager : public MutexManager {
 public:
 	OSystem::MutexRef createMutex();
 	void lockMutex(OSystem::MutexRef mutex);