gistfile1.txt

struct DTimer 
{
	HANDLE _M_hTimer = 0;
	LONG _M_dwRefCount = 1;
	ULONG _M_n = 0;
	ULONG _M_dwThreadId = GetCurrentThreadId();
	LONG _M_stopping = FALSE;

	void AddRef()
	{
		InterlockedIncrementNoFence(&_M_dwRefCount);
	}

	void Release()
	{
		if (!InterlockedDecrement(&_M_dwRefCount))
		{
			delete this;
		}
	}

	void OnTimer()
	{
		printf("%x: %s<%p>(%x)\n", GetCurrentThreadId(), __FUNCTION__, this, _M_n);

		if (!--_M_n)
		{
			Stop();
		}
	}

	static VOID NTAPI WaitOrTimerCallback(PVOID This, BOOLEAN )
	{
		reinterpret_cast<DTimer*>(This)->OnTimer();
	}

	static void NTAPI timer_canceled_callback(PVOID This)
	{
		printf("%x: %s<%p>\n", GetCurrentThreadId(), __FUNCTION__, This);

		/////////////////////////////////////////////////////////////////////
		/////////////////////////////////////////////////////////////////////
		/////////////////////////////////////////////////////////////////////
		/////////////////////////////////////////////////////////////////////
		// Simulate a long cleanup here
		Sleep(5000);

		reinterpret_cast<DTimer*>(This)->Release();
	}

	DTimer(ULONG n) : _M_n(n)
	{
		printf("%x: %s<%p>\n", GetCurrentThreadId(), __FUNCTION__, this);
	}

	~DTimer()
	{
		printf("%x: %s<%p>\n", GetCurrentThreadId(), __FUNCTION__, this);
		if (_M_hTimer)
		{
			timer_release(_M_hTimer);
		}

		PostThreadMessageW(_M_dwThreadId, WM_QUIT, 0, 0);
	}

	BOOL Start(_In_ DWORD DueTime, _In_ DWORD Period)
	{
		AddRef();
		if (timer_create(&_M_hTimer, WaitOrTimerCallback, this, DueTime, Period))
		{
			return TRUE;
		}
		Release();

		return FALSE;
	}

	void Stop()
	{
		if (!InterlockedExchangeNoFence(&_M_stopping, TRUE))
		{
			timer_cancel(_M_hTimer, timer_canceled_callback, this);
		}
	}
};

void t_test(ULONG n)
{
	if (DTimer* timer = new DTimer(n))
	{
		if (timer->Start(0, 1000))
		{
			timer->Stop();
		}
		timer->Release();
	}

	MessageBox(0, 0, L"demo delay", MB_ICONWARNING);
}