Refactor, cleanup status logic, extract join occupy logic into modules

src/net.rs

@@ -0,0 +1,22 @@
+use std::error::Error;
+use std::io;
+use tokio::io::AsyncWriteExt;
+use tokio::net::TcpStream;
+
+/// Gracefully close given TCP stream.
+///
+/// Intended as helper to make code less messy. This also succeeds if already closed.
+pub async fn close_tcp_stream(mut stream: TcpStream) -> Result<(), Box<dyn Error>> {
+    close_tcp_stream_ref(&mut stream).await
+}
+
+/// Gracefully close given TCP stream.
+///
+/// Intended as helper to make code less messy. This also succeeds if already closed.
+pub async fn close_tcp_stream_ref(stream: &mut TcpStream) -> Result<(), Box<dyn Error>> {
+    match stream.shutdown().await {
+        Ok(_) => Ok(()),
+        Err(err) if err.kind() == io::ErrorKind::NotConnected => Ok(()),
+        Err(err) => Err(err.into()),
+    }
+}