Reverse engineered sources to this weird Konami PS3 Dance-Mat Input converter

DDR_Fix_reverse_engineer.cpp

// DDR_Fix_reverse_engineer.cpp 
// Reverse engineered code from the rawinput_ps3_ddr.exe floating around on the net
//

#include <iostream>
#include "Windows.h"

const int ARR_SZ = 16;
DWORD g_PreviousPadState[ARR_SZ];

void UsrSendKey(int key, bool bDownState)
{
	UINT numInserted;
	const char* lpState;
	INPUT input;
	input.type = INPUT_KEYBOARD;
	input.ki.wVk = 0;
	input.ki.wScan =(WORD)key;
	if (bDownState == false) {
		input.ki.dwFlags = KEYEVENTF_KEYUP;
		input.ki.time = 0;
		input.ki.dwExtraInfo = 0;
		numInserted = SendInput(1, &input, 0x1c);
		lpState = "up";
	}
	else {
		input.ki.dwFlags = KEYEVENTF_KEYUP;
		input.ki.time = 0;
		input.ki.dwExtraInfo = 0;
		numInserted = SendInput(1, &input, 0x1c);
		lpState = "down";
	}
	printf("SendInput: k=%d %s r=%d\n", key, lpState, numInserted);
	return;
}


LRESULT CALLBACK WindowProc(
	_In_ HWND   hwnd,
	_In_ UINT   uMsg,
	_In_ WPARAM wParam,
	_In_ LPARAM lParam
)
{
	LRESULT ret;
	HRAWINPUT hRawInput = (HRAWINPUT)lParam;

	
	RAWINPUTHEADER pRawHeader;
	unsigned uLen;
	size_t size;
	char* currentPadState = nullptr;

	if (uMsg == WM_DESTROY)
	{
		PostQuitMessage(0);
		return 0;
	}
	if (uMsg == WM_INPUT)
	{
		uLen = sizeof(pRawHeader);
		UINT uBytesCopied = GetRawInputData(hRawInput, RID_HEADER, &pRawHeader, &uLen, sizeof(RAWINPUTHEADER));
		if (uBytesCopied != UINT(-1))
		{
			//get required length
			GetRawInputData(hRawInput, RID_INPUT, (LPVOID)0x0, &uLen, sizeof(RAWINPUTHEADER));
			currentPadState = new char[uLen];
			RAWINPUT* inp = (RAWINPUT*)currentPadState;
			//fetch data
			GetRawInputData(hRawInput, RID_INPUT, currentPadState, &uLen, sizeof(RAWINPUTHEADER));
			if (((char*)g_PreviousPadState)[9] != inp->data.hid.bRawData[9]) {
				UsrSendKey(0x41e, /*currentPadState[0x21]*/inp->data.hid.bRawData[9] != '\0');//1e = A
			}
			if (((char*)g_PreviousPadState)[8]  != inp->data.hid.bRawData[8]) {
				UsrSendKey(0x430, /*currentPadState[0x20]*/inp->data.hid.bRawData[8] != '\0');//30 = B
			}
			if (((char*)g_PreviousPadState)[10] != inp->data.hid.bRawData[10]) {
				UsrSendKey(0x42e, /*currentPadState[0x22]*/inp->data.hid.bRawData[10] != '\0');//2e = C
			}
			if (((char*)g_PreviousPadState)[11] != inp->data.hid.bRawData[11]) {
				UsrSendKey(0x420, /*currentPadState[0x23]*/inp->data.hid.bRawData[11] != '\0');//20 = D
			}

			UINT numBytes = inp->data.hid.dwSizeHid;
			DWORD* startStateData = (DWORD*)(&inp->data.hid.bRawData);
			memcpy(g_PreviousPadState, startStateData, numBytes);
			delete[] currentPadState;
			return 0;
		}
		fwrite("error getting RID_HEADER\n", 1, 0x19, stderr);
		ret = -1;
	}
	else
	{
		ret = DefWindowProcA(hwnd,uMsg,wParam, lParam);;
	}
	return ret;
}

BOOL RegisterRawInputDevice(HWND hWnd)
{
	RAWINPUTDEVICE inpDevice;

	inpDevice.hwndTarget = hWnd;
	inpDevice.usUsagePage = 1;
	inpDevice.usUsage = 5;
	inpDevice.dwFlags = RIDEV_INPUTSINK;
	BOOL bSuccess = RegisterRawInputDevices(&inpDevice,1,sizeof(RAWINPUTDEVICE));
	if (bSuccess == FALSE)
	{
		fwrite("Error registering input", 1, 0x17, stderr);
	}
	return bSuccess;
}

int WINAPI WinMain(
	_In_ HINSTANCE hInstance,
	_In_opt_ HINSTANCE hPrevInstance,
	_In_ LPSTR lpCmdLine,
	_In_ int nShowCmd
)
{
	HWND hWnd;
	MSG msg;
	const char* className = "WindowsApp";

	WNDCLASSEXA wndClass;
	wndClass.cbSize = sizeof(WNDCLASSEXA);
	wndClass.style = CS_DBLCLKS;
	wndClass.lpfnWndProc = &WindowProc;
	wndClass.cbClsExtra = 0;
	wndClass.cbWndExtra = 0;
	wndClass.hInstance = hInstance;
	wndClass.hIcon = LoadIconA(0x0, IDI_APPLICATION);
	wndClass.hCursor = LoadCursorA(0x0, IDC_ARROW);
	wndClass.hbrBackground = (HBRUSH)COLOR_BACKGROUND;
	wndClass.lpszMenuName = (LPCSTR)0x0;
	wndClass.lpszClassName = className;
	wndClass.hIconSm = LoadIconA((HINSTANCE)0x0, IDI_APPLICATION);

	ATOM cls = RegisterClassExA(&wndClass);
	int return_value = 0;
	if (cls)
	{
		hWnd = CreateWindowExA(0,className, "PS3-DDR-DanceMat Input Converter", WS_GROUP| WS_SYSMENU,
			CW_USEDEFAULT, CW_USEDEFAULT, 320, 200, (HWND)0x0, (HMENU)0x0, hInstance, (LPVOID)0x0);
		ShowWindow(hWnd, nShowCmd);
		memset(g_PreviousPadState,0,sizeof(g_PreviousPadState));
		BOOL bSuccess = RegisterRawInputDevice(hWnd);
		if (bSuccess)
		{
			while (true) {
				BOOL bContinue = GetMessageA(&msg,(HWND)0,0,0);
				if (!bContinue)
					break;
				TranslateMessage(&msg);
				DispatchMessageA(&msg);
			}
			return msg.wParam;
		}
	}
	return return_value;
}