probably working serial output

chuniio/src/lib.rs

@@ -324,7 +324,10 @@ pub extern "C" fn chuni_io_led_init() -> HRESULT {
 #[no_mangle]
 #[cfg(any(chuni, chusanapp))]
 pub extern "C" fn chuni_io_led_init() -> HRESULT {
-    serial::serial_led_init()
+    // If this fails, it is not a failure for the YubiDeck LEDs
+    serial::serial_led_init();
+
+    S_OK
 }
 
 #[no_mangle]

chuniio/src/serial.rs

@@ -1,10 +1,70 @@
-use winapi::shared::winerror::S_OK;
-use winapi::um::winnt::HRESULT;
+use std::io::Write;
+use std::sync::Mutex;
+use std::time::Duration;
+use lazy_static::lazy_static;
+use log::error;
+use serialport::{SerialPort};
 
-pub fn serial_led_init() -> HRESULT {
-    S_OK
+lazy_static! {
+    static ref SERIAL_PORT: Option<Mutex<Box<dyn SerialPort>>> = open_port();
+}
+
+const BOARD_0_LEDS: i32 = 53 * 3;
+const BOARD_1_LEDS: i32 = 63 * 3;
+
+const FRAMING_BYTE: u8 = 0xE0;
+const ESCAPE_BYTE: u8 = 0xD0;
+
+fn open_port() -> Option<Mutex<Box<dyn SerialPort>>> {
+    let builder = serialport::new("COM10", 921600)
+        .timeout(Duration::from_secs(0));
+
+    match builder.open() {
+        Ok(port) => Some(Mutex::new(port)),
+        Err(e) => {
+            error!("error opening serial port for LED output: {e:#?}");
+            None
+        }
+    }
 }
 
 pub fn serial_led_set(board: u8, rgb: *const u8) {
+    let port = match &*SERIAL_PORT {
+        None => return,
+        Some(p) => p,
+    };
 
+    // We need to escape the data, the same as how segatools does it
+    let escaped = match escape_data(board, rgb) {
+        Ok(data) => data,
+        Err(e) => return,
+    };
+
+    let mut serial = port.lock().unwrap();
+    if serial.write(escaped.as_slice()).is_err() {
+        error!("error writing serial led data: {e:#?}");
+    }
+}
+
+fn escape_data(board: u8, rgb: *const u8) -> Result<Vec<u8>, &'static str> {
+    let mut escaped = vec![ESCAPE_BYTE, board];
+
+    let len = match board {
+        0 => BOARD_0_LEDS,
+        1 => BOARD_1_LEDS,
+        _ => return Err("invalid board id"),
+    };
+
+    for i in 0..len {
+        let mut byte = rgb[i];
+
+        if byte == ESCAPE_BYTE || byte == FRAMING_BYTE {
+            escaped.push(ESCAPE_BYTE);
+            byte -= 1;
+        }
+
+        escaped.push(byte);
+    }
+
+    Ok(escaped)
 }