rust stdlib signal handling in linux

signal_handle.rs

fn handle_signals() -> c_int {
	let mut mask: sigset_t = unsafe {
		let mut masku = MaybeUninit::<sigset_t>::uninit();
		sigemptyset(masku.as_mut_ptr());
		masku.assume_init()
	};
	unsafe { sigaddset(&mut mask, SIGINT) };
	unsafe { sigaddset(&mut mask, SIGTERM) };
	unsafe { sigprocmask(SIG_BLOCK, &mask, ptr::null_mut()) };
	let signal = unsafe { sigwaitinfo(&mask, ptr::null_mut()) } as i32;
	return signal;
} 

fn health_service() {
	println!("Starting health service");
	let listener = TcpListener::bind("0.0.0.0:8080").unwrap();
	for stream in listener.incoming() {
		thread::spawn(move || {
			let mut stream = stream.unwrap();
			let healthy_resp = b"HTTP/1.1 200 OK\r\n\r\n";
			let unhealthy_resp = b"HTTP/1.1 503 Service Unavailable\r\n\r\n";
			let response = match healthy() {
				Ok(_) => &healthy_resp[..],
				_ => &unhealthy_resp[..],
			};
			match stream.write_all(response) {
				Ok(_) => println!("Health response sent"),
				Err(e) => println!("Failed sending health response: {}!", e),
			};
			stream.shutdown(Shutdown::Write).unwrap();
		});
	}
}

fn main() {
	println!("Started daemon");

	thread::spawn(|| {
		health_service();
	});

	let sig_num = handle_signals();
	
	exit(sig_num);
}