Add separate Closed message

src/connections.rs

@@ -66,12 +66,12 @@ impl ConnectionManager {
     pub fn send_pings(&mut self) {
         let now = Instant::now();
 
-        if let Some(closing_since) = self.closing_since {
+        if let Some(closing_since) = self.closing_since
+            && !self.udp.is_closed()
+        {
             if self.connections.len() == 0 {
-                println!("UDP closed");
                 self.udp.close();
             } else if now - closing_since > Duration::from_millis(1000) {
-                println!("UDP closed");
                 self.udp.close();
             }
         }

src/lib.rs

@@ -31,6 +31,7 @@ pub enum PeerError {
 pub enum PeerMessage {
     NewConnection(Connection),
     Disconnected(Connection, Option<ConnectionError>),
+    Closed,
 }
 
 pub struct Peer {
@@ -79,7 +80,10 @@ impl Peer {
     #[must_use]
     pub fn poll(&mut self) -> Result<Option<PeerMessage>, PeerError> {
         if self.connection_mgr.udp.is_closed() {
-            self.closed.store(true, Ordering::Relaxed);
+            if self.closed.load(Ordering::Acquire) {
+                self.messages.push_back(PeerMessage::Closed);
+            }
+            self.closed.store(true, Ordering::Release);
         }
 
         self.connection_mgr.send_pings();