Actually fix the race and panics on shutdown

2458df9 was a move in the right direction, but it wasn't enough. We need
to do same thing for the conn event listers too.

Basically the UI task relies on the UI event channel being dropped on
the sender side. That happens when we do C-c, and UI task returns.

Similarly connection tasks now relies on the conn chans being dropped.
Clients now return after sending Quit message (same as before), and we
no longer need a Closed message to send the connection event listener
tasks.

libtiny_client/src/lib.rs

@@ -98,10 +98,6 @@ pub enum Event {
     NickChange(String),
     /// A message from the server
     Msg(wire::Msg),
-
-    /// This is to signal the task that listens for events to stop.
-    // TODO: Maybe try something like making Client non-Clone and sharing Weaks with tasks
-    Closed,
 }
 
 impl From<StreamError> for Event {
@@ -127,10 +123,6 @@ pub struct Client {
     /// Reference to the state, to be able to provide methods like `get_nick` and
     /// `is_nick_accepted`.
     state: State,
-    // We can't have a channel to the sender task directly here, because when the sender task
-    // returns we lose the receiving end of the channel and there's no way to avoid this except
-    // with annoying hacks like wrapping it with an `Arc<Mutex<..>>` or something.
-    snd_ev: mpsc::Sender<Event>,
 }
 
 impl Client {
@@ -249,7 +241,6 @@ impl Client {
     pub fn quit(&mut self, reason: Option<String>) {
         debug!("quit cmd received");
         self.msg_chan.try_send(Cmd::Quit(reason)).unwrap();
-        self.snd_ev.try_send(Event::Closed).unwrap();
     }
 
     /// Get all nicks in a channel.
@@ -283,7 +274,6 @@ fn connect(server_info: ServerInfo) -> (Client, mpsc::Receiver<Event>) {
 
     // Channel for returning IRC events to user.
     let (snd_ev, rcv_ev) = mpsc::channel::<Event>(100);
-    let snd_ev_clone = snd_ev.clone(); // for Client
 
     // Channel for commands from user.
     let (snd_cmd, rcv_cmd) = mpsc::channel::<Cmd>(100);
@@ -303,7 +293,6 @@ fn connect(server_info: ServerInfo) -> (Client, mpsc::Receiver<Event>) {
             msg_chan: snd_cmd,
             serv_name,
             state: irc_state,
-            snd_ev: snd_ev_clone,
         },
         rcv_ev,
     )
@@ -395,7 +384,7 @@ async fn main_loop(
 
         if addrs.is_empty() {
             snd_ev.send(Event::CantResolveAddr).await.unwrap();
-            break; // returns
+            return;
         }
 
         debug!("Address resolved: {:?}", addrs);

termbox/src/lib.rs

@@ -184,8 +184,7 @@ impl Termbox {
         self.output_buffer
             .extend_from_slice(termion::clear::All.as_ref());
         // T_EXIT_CA for xterm
-        self.output_buffer
-            .extend_from_slice(b"\x1b[?1049l");
+        self.output_buffer.extend_from_slice(b"\x1b[?1049l");
 
         self.flush_output_buffer();
     }
@@ -458,8 +457,7 @@ impl Drop for Termbox {
         self.output_buffer
             .extend_from_slice(termion::clear::All.as_ref());
         // T_EXIT_CA for xterm
-        self.output_buffer
-            .extend_from_slice(b"\x1b[?1049l");
+        self.output_buffer.extend_from_slice(b"\x1b[?1049l");
         self.flush_output_buffer();
 
         unsafe {

tiny/src/conn.rs

@@ -15,14 +15,12 @@ pub(crate) async fn task(
     client: Client,
 ) {
     while let Some(ev) = rcv_ev.next().await {
-        if handle_conn_ev(&*ui, &client, ev) {
-            return;
-        }
+        handle_conn_ev(&*ui, &client, ev);
         ui.draw();
     }
 }
 
-fn handle_conn_ev(ui: &dyn UI, client: &Client, ev: libtiny_client::Event) -> bool {
+fn handle_conn_ev(ui: &dyn UI, client: &Client, ev: libtiny_client::Event) {
     use libtiny_client::Event::*;
     match ev {
         ResolvingHost => {
@@ -104,11 +102,7 @@ fn handle_conn_ev(ui: &dyn UI, client: &Client, ev: libtiny_client::Event) -> bo
         Msg(msg) => {
             handle_irc_msg(ui, client, msg);
         }
-        Closed => {
-            return true;
-        }
     }
-    false
 }
 
 fn handle_irc_msg(ui: &dyn UI, client: &Client, msg: wire::Msg) {