Listen for ROG notebook FN keystrokes.

0_rog_key.md

What's that?

This tool will listen for ASUS notebook's FN keystrokes. And it will map ROG key to Scroll Lock and Fan key to Num Lock. (Ctrl + Num Lock = Pause key).

Compile and run

$ clang main.cpp -o rog.exe && rog.exe

main.cpp

// Introduce some shit (a.k.a. winapi)
#define UNICODE
#include <windows.h>
#pragma comment(lib, "user32")

// #include <fcntl.h>
#define _O_U16TEXT 0x00020000
#define _O_U8TEXT 0x00040000

#include <io.h>
#include <stdio.h>

enum ASUSKEYS : UINT {
	ROG_KEY = 56,
	FN_F10 = 107,
	MUTE = 124,
	FN_V = 138,
	FN_C = 158,
	FN_F5 = 174,
	FN_LEFT = 178,
	FN_RIGHT = 179,
	FN_UP = 196,
	FN_DOWN = 197,

	// Aliases
	FAN_KEY = FN_F5,
};

const wchar_t pClassName[] = L"ROGKeyRebind";
const wchar_t pWindowName[] = L"ROGKeyRebind";
UINT pAPCI = RegisterWindowMessageW(L"ACPI Notification through ATKHotkey from BIOS");

void SendScanCode(WORD scancode) {
	INPUT ip;
	ip.type = INPUT_KEYBOARD;
	ip.ki.time = 0;
	ip.ki.wVk = 0;
	ip.ki.dwExtraInfo = 0;

	ip.ki.dwFlags = KEYEVENTF_SCANCODE;
	ip.ki.wScan = scancode;

	SendInput(1, &ip, sizeof(INPUT));

	ip.ki.dwFlags = KEYEVENTF_SCANCODE | KEYEVENTF_KEYUP;
	SendInput(1, &ip, sizeof(INPUT));
	return;
}

LRESULT CALLBACK MainWndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
	if (uMsg == pAPCI) {
		switch (wParam) {
		case ASUSKEYS::MUTE:
			wprintf(L"Mute key\n");
			break;
		case ASUSKEYS::FAN_KEY:
			wprintf(L"Fan key\n");
			SendScanCode(0x45); // Send NumLock

			break;
		case ASUSKEYS::ROG_KEY:
			wprintf(L"ROG key\n");

			SendScanCode(0x46); // Send ScrollLock
			break;
		case ASUSKEYS::FN_F10:
			wprintf(L"Fn + 10 key\n");
			break;
		case ASUSKEYS::FN_C:
			wprintf(L"Fn + C key\n");
			break;
		case ASUSKEYS::FN_V:
			wprintf(L"Fn + V key\n");
			break;
		case ASUSKEYS::FN_UP:
			wprintf(L"Fn + Up Arrow key\n");
			break;
		case ASUSKEYS::FN_LEFT:
			wprintf(L"Fn + Left Arrow key\n");
			break;
		case ASUSKEYS::FN_DOWN:
			wprintf(L"Fn + Down Arrow key\n");
			break;
		case ASUSKEYS::FN_RIGHT:
			wprintf(L"Fn + Right Arrow key\n");
			break;
		default:
			wprintf(L"Unknown key: %d\n", wParam);
			break;
		}
	} else {
		switch (uMsg) {
		case WM_DESTROY:
			wprintf(L"Error window destroyed. Shutting down.\n");
			PostQuitMessage(0);
			ExitProcess(4);
			break;
		default:
			break;
		}
	}
	return DefWindowProcW(hWnd, uMsg, wParam, lParam);
} 

int main() {
	_setmode(_fileno(stdout), _O_U16TEXT);

	HMODULE hInst = GetModuleHandleW(nullptr);
	if (hInst == 0) {
		wprintf(L"Error getting module.\n");
		return 2;
	}

	WNDCLASSEXW wc = {};

	wc.lpfnWndProc = MainWndProc;
	wc.hInstance = hInst;
	wc.lpszClassName = pWindowName;
	wc.cbSize = sizeof(wc);

	RegisterClassEx(&wc);

	HWND hWnd = CreateWindowExW(
		0,
		wc.lpszClassName,
		pWindowName,
		WS_VISIBLE,
		-1, -1, 1, 1,
		nullptr,
		nullptr,
		hInst,
		nullptr
	);

	if (hWnd == 0)	{
		wprintf(L"Error spawning window.\n");
		return 3;
	}

	ShowWindow(hWnd, SW_HIDE);

	ChangeWindowMessageFilterEx(
		hWnd,
		pAPCI,
		MSGFLT_ALLOW,
		nullptr
	);

	wprintf(L"Listening for keys.\n");

	MSG msg;
	int bRet = -1;
	while ((bRet = GetMessageW(&msg, hWnd, 0, 0)) != 0) {
		if (bRet < 0) {
			wprintf(L"Unknown error while getting message.");
			return 1;
		} else {
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
	}
	wprintf(L"Shutting down.\n");
	return 0;
}