The Modular WASM-based RTOS for the Edge

#[link(wasm_import_module = "akira")]
extern "C" {
    fn log(msg: *const u8, len: u32);
    fn sensor_read(sensor_id: u32, buffer: *mut u8, len: u32) -> i32;
    fn get_time_ms() -> u64;
}

#[no_mangle]
pub extern "C" fn _start() {
    unsafe {
        let msg = b"Sensor reader v1.0 starting...";
        log(msg.as_ptr(), msg.len() as u32);
        
        let mut data = [0u8; 64];
        loop {
            if sensor_read(0, data.as_mut_ptr(), data.len() as u32) > 0 {
                let msg = b"Temperature: 24.5°C";
                log(msg.as_ptr(), msg.len() as u32);
            }
            wait(5000); // Every 5 seconds
        }
    }
}

fn wait(ms: u64) {
    unsafe {
        let target = get_time_ms() + ms;
        while get_time_ms() < target {}
    }
}