GEEKING

WindowsClient/FunctionMarshaller.h

@@ -0,0 +1,80 @@
+#pragma once
+
+// TODO: refactor this class so it doesn't use ATL
+
+#ifndef _WIN32
+// This code is platform-specific
+#error
+#endif
+
+#include "atlbase.h"
+#include "AtlWin.h"
+#include <map>
+#include "rbx/threadsafe.h"
+#include "rbx/atomic.h"
+
+namespace RBX {
+
+// A very handy class for marshaling a function across Windows
+// threads (sync and async)
+class FunctionMarshaller
+	: public ATL::CWindowImpl<FunctionMarshaller>
+{
+	const static int WM_EVENT = WM_USER + 101;		// See Q196026
+	const static int WM_ASYNCEVENT = WM_USER + 102;		// See Q196026
+
+	LRESULT OnEvent(UINT uMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
+	LRESULT OnAsyncEvent(UINT uMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
+
+	struct StaticData
+	{
+		std::map<DWORD, FunctionMarshaller*> windows;
+
+		// TODO: Would non-recursive be safe here?
+		boost::recursive_mutex windowsCriticalSection;
+		~StaticData();
+	};
+	SAFE_STATIC(StaticData, staticData)
+
+	rbx::safe_queue<boost::function<void()>*> asyncCalls;
+
+	rbx::atomic<LONG> postedAsyncMessage;
+	int refCount;
+	DWORD threadID;
+
+	FunctionMarshaller(DWORD threadID);
+	~FunctionMarshaller();
+public:
+	// see Q196026
+	DECLARE_WND_CLASS("Roblox.FunctionMarshaller")
+
+	// TODO: Wrap with a reference counter and then remove ~StaticData()
+	// cleanup code and remove ReleaseWindow()
+	static FunctionMarshaller* GetWindow();
+
+	static void ReleaseWindow(FunctionMarshaller* window);
+
+	struct Closure
+	{
+		boost::function<void()>* f;
+		std::string errorMessage;
+	};
+
+	// Executes the given function.
+	void Execute(boost::function<void()> job);
+
+	// Submits a function to be executed by a separate thread.
+	void Submit(boost::function<void()> job);
+
+	// Call this only from the Window's thread.
+	void ProcessMessages();
+
+	BEGIN_MSG_MAP(MarshaledListener)
+		MESSAGE_HANDLER(WM_EVENT, OnEvent)
+		MESSAGE_HANDLER(WM_ASYNCEVENT, OnAsyncEvent)
+	END_MSG_MAP()
+
+	virtual void OnFinalMessage(HWND hWnd);
+};
+
+}  // namespace RBX