Merge pull request #933 from jwilm/misc-client-fixes

Misc client fixes

src/client/mod.rs

@@ -372,7 +372,7 @@ macro_rules! conn_response {
             }
             None => {
                 if let Some((key, socket)) = $scope.awaiting_slot.pop_front() {
-                    rotor_try!($scope.register(&socket, EventSet::writable(), PollOpt::level()));
+                    rotor_try!($scope.register(&socket, EventSet::writable() | EventSet::hup(), PollOpt::level()));
                     rotor::Response::ok(ClientFsm::Connecting((key, socket)))
                 } else {
                     rotor::Response::done()
@@ -460,7 +460,7 @@ where C: Connect,
     type Seed = (C::Key, C::Output);
 
     fn create(seed: Self::Seed, scope: &mut Scope<Self::Context>) -> rotor::Response<Self, rotor::Void> {
-        rotor_try!(scope.register(&seed.1, EventSet::writable(), PollOpt::level()));
+        rotor_try!(scope.register(&seed.1, EventSet::writable() | EventSet::hup(), PollOpt::level()));
         rotor::Response::ok(ClientFsm::Connecting(seed))
     }
 
@@ -483,11 +483,11 @@ where C: Connect,
                     if let Some(err) = seed.1.take_socket_error().err() {
                         debug!("error while connecting: {:?}", err);
                         scope.pop_queue(&seed.0).map(move |mut queued| queued.handler.on_error(::Error::Io(err)));
-                        rotor::Response::done()
                     } else {
                         trace!("connecting is_error, but no socket error");
-                        rotor::Response::ok(ClientFsm::Connecting(seed))
                     }
+
+                    rotor::Response::done()
                 } else if events.is_writable() {
                     if scope.queue.contains_key(&seed.0) {
                         trace!("connected and writable {:?}", seed.0);
@@ -541,6 +541,7 @@ where C: Connect,
 
                 // Check all idle connections regardless of origin
                 for (key, idle) in scope.idle_conns.iter_mut() {
+                    // Pop from the front since those are lease recently used
                     while let Some(ctrl) = idle.pop_front() {
                         // Signal connection to close. An err here means the
                         // socket is already dead can should be tossed.
@@ -667,7 +668,9 @@ where C: Connect,
                                 let mut remove_idle = false;
                                 let mut woke_up = false;
                                 if let Some(mut idle) = scope.idle_conns.get_mut(&key) {
-                                    while let Some(ctrl) = idle.pop_front() {
+                                    // Pop from back since those are most recently used. Connections
+                                    // at the front are allowed to expire.
+                                    while let Some(ctrl) = idle.pop_back() {
                                         // err means the socket has since died
                                         if ctrl.ready(Next::write()).is_ok() {
                                             woke_up = true;

src/http/conn.rs

@@ -37,6 +37,10 @@ struct ConnInner<K: Key, T: Transport, H: MessageHandler<T>> {
     key: K,
     state: State<H, T>,
     transport: T,
+    /// Records a WouldBlock error when trying to read
+    ///
+    /// This flag is used to prevent busy looping
+    read_would_block: bool,
 }
 
 impl<K: Key, T: Transport, H: MessageHandler<T>> fmt::Debug for ConnInner<K, T, H> {
@@ -153,7 +157,10 @@ impl<K: Key, T: Transport, H: MessageHandler<T>> ConnInner<K, T, H> {
                     Ok(head) => head,
                     Err(::Error::Io(e)) => match e.kind() {
                         io::ErrorKind::WouldBlock |
-                        io::ErrorKind::Interrupted => return state,
+                        io::ErrorKind::Interrupted => {
+                            self.read_would_block = true;
+                            return state;
+                        },
                         _ => {
                             debug!("io error trying to parse {:?}", e);
                             return State::Closed;
@@ -236,6 +243,30 @@ impl<K: Key, T: Transport, H: MessageHandler<T>> ConnInner<K, T, H> {
                     }
                 }
             },
+            State::Init { interest: Next_::Wait, .. } => {
+                match self.buf.read_from(&mut self.transport) {
+                    Ok(0) => {
+                        // End-of-file; connection was closed by peer
+                        State::Closed
+                    },
+                    Ok(n) => {
+                        // Didn't expect bytes here! Close the connection.
+                        warn!("read {} bytes in State::Init with Wait interest", n);
+                        State::Closed
+                    },
+                    Err(e) => match e.kind() {
+                        io::ErrorKind::WouldBlock => {
+                            // This is the expected case reading in this state
+                            self.read_would_block = true;
+                            state
+                        },
+                        _ => {
+                            warn!("socket error reading State::Init with Wait interest: {}", e);
+                            State::Closed
+                        }
+                    }
+                }
+            },
             State::Init { .. } => {
                 trace!("on_readable State::{:?}", state);
                 state
@@ -265,7 +296,10 @@ impl<K: Key, T: Transport, H: MessageHandler<T>> ConnInner<K, T, H> {
                         },
                         Err(::Error::Io(e)) => match e.kind() {
                             io::ErrorKind::WouldBlock |
-                            io::ErrorKind::Interrupted => None,
+                            io::ErrorKind::Interrupted => {
+                                self.read_would_block = true;
+                                None
+                            },
                             _ => {
                                 debug!("io error trying to parse {:?}", e);
                                 return State::Closed;
@@ -459,10 +493,15 @@ impl<K: Key, T: Transport, H: MessageHandler<T>> ConnInner<K, T, H> {
     }
 
     fn can_read_more(&self, was_init: bool) -> bool {
-        match self.state {
+        let transport_blocked = self.transport.blocked().is_some();
+        let read_would_block = self.read_would_block;
+
+        let state_machine_ok = match self.state {
             State::Init { .. } => !was_init && !self.buf.is_empty(),
             _ => !self.buf.is_empty()
-        }
+        };
+
+        !transport_blocked && !read_would_block && state_machine_ok
     }
 
     fn on_error<F>(&mut self, err: ::Error, factory: &F) where F: MessageHandlerFactory<K, T> {
@@ -478,6 +517,8 @@ impl<K: Key, T: Transport, H: MessageHandler<T>> ConnInner<K, T, H> {
 
     fn on_readable<F>(&mut self, scope: &mut Scope<F>)
     where F: MessageHandlerFactory<K, T, Output=H> {
+        // Clear would_block flag so state is clear going into read
+        self.read_would_block = false;
         trace!("on_readable -> {:?}", self.state);
         let state = mem::replace(&mut self.state, State::Closed);
         self.state = self.read(scope, state);
@@ -526,6 +567,7 @@ impl<K: Key, T: Transport, H: MessageHandler<T>> Conn<K, T, H> {
                 timeout_start: Some(now),
             },
             transport: transport,
+            read_would_block: false,
         }))
     }