Remove duplicate code

examples/nfct_test.rs

@@ -36,6 +36,16 @@ fn print_rx_buffer(buf: &mut [u8], amount: usize) {
     writeln!(console, " {:02x?}", buf[amount - 1]).unwrap();
 }
 
+#[allow(dead_code)]
+/// Helper function to write on console the received packet.
+fn transmit_slice(buf: &mut [u8] {
+    let amount = buf.len();
+    match NfcTag::transmit(&mut buf, amount) {
+        Ok(_) => (),
+        Err(_) => writeln!(console, " -- tx error!").unwrap(),
+    }
+}
+
 #[cfg(feature = "with_nfc")]
 #[derive(PartialEq, Eq)]
 /// enum for reserving the NFC tag state.
@@ -72,46 +82,30 @@ fn main() {
                         Err(TockError::Command(CommandError {
                             return_code: value, ..
                         })) => writeln!(console, " -- Err({})!", value).unwrap(),
-                        Err(_) => writeln!(console, " -- RX ERROR").unwrap(),
+                        Err(_) => writeln!(console, " -- RX Err").unwrap(),
                     }
 
                     match rx_buf[0] {
                         0xe0 /* RATS */=> {
                             let mut answer_to_select = [0x05, 0x78, 0x80, 0xB1, 0x00];
-                            let amount = answer_to_select.len();
+                            transmit_slice(&mut answer_to_select);
-                            match NfcTag::transmit(&mut answer_to_select, amount) {
-                                Ok(_) => (),
-                                Err(_) => writeln!(console, " -- tx error!").unwrap(),
-                            }
                         }
                         0xc2 /* DESELECT */ => {
                             // Ignore the request
                             let mut command_error = [0x6A, 0x81];
-                            let amount = command_error.len();
+                            transmit_slice(&mut command_error);
-                            match NfcTag::transmit(&mut command_error, amount) {
-                                Ok(_) => (),
-                                Err(_) => writeln!(console, " -- tx error!").unwrap(),
-                            }
                         }
                         0x02 | 0x03 /* APDU Prefix */ => {
                             // If the received packet is applet selection command (FIDO 2)
                             if rx_buf[1] == 0x00 && rx_buf[2] == 0xa4 && rx_buf[3] == 0x04 {
-                                // Vesion: "U2F_V2"
+                                /// Vesion: "U2F_V2"
                                 // let mut reply = [rx_buf[0], 0x55, 0x32, 0x46, 0x5f, 0x56, 0x32, 0x90, 0x00,];
-                                // Vesion: "FIDO_2_0"
+                                /// Vesion: "FIDO_2_0"
                                 let mut reply = [rx_buf[0], 0x46, 0x49, 0x44, 0x4f, 0x5f, 0x32, 0x5f, 0x30, 0x90, 0x00,];
-                                let amount = reply.len();
+                                transmit_slice(&mut reply);
-                                match NfcTag::transmit(&mut reply, amount) {
-                                    Ok(_) => (),
-                                    Err(_) => writeln!(console, " -- tx error!").unwrap(),
-                                }
                             } else {
                                 let mut reply = [rx_buf[0], 0x90, 0x00];
-                                let amount = reply.len();
+                                transmit_slice(&mut reply);
-                                match NfcTag::transmit(&mut reply, amount) {
-                                    Ok(_) => (),
-                                    Err(_) => writeln!(console, " -- tx error!").unwrap(),
-                                }
                             }
                         }
                         0x52 | 0x50 /* WUPA | Halt */ => {