Add missing files

project/src/backend/sdl/SDLMutex.cpp

@@ -0,0 +1,65 @@
+#include <system/Mutex.h>
+#include <SDL.h>
+
+
+namespace lime {
+	
+	
+	Mutex::Mutex () {
+		
+		mutex = SDL_CreateMutex ();
+		
+	}
+	
+	
+	Mutex::~Mutex () {
+		
+		if (mutex) {
+			
+			SDL_DestroyMutex ((SDL_mutex*)mutex);
+			
+		}
+		
+	}
+	
+	
+	bool Mutex::Lock () {
+		
+		if (mutex) {
+			
+			return SDL_LockMutex ((SDL_mutex*)mutex) == 0;
+			
+		}
+		
+		return false;
+		
+	}
+	
+	
+	bool Mutex::TryLock () {
+		
+		if (mutex) {
+			
+			return SDL_TryLockMutex ((SDL_mutex*)mutex) == 0;
+			
+		}
+		
+		return false;
+		
+	}
+	
+	
+	bool Mutex::Unlock () {
+		
+		if (mutex) {
+			
+			return SDL_UnlockMutex ((SDL_mutex*)mutex) == 0;
+			
+		}
+		
+		return false;
+		
+	}
+	
+	
+}