fix(client): replace deferred open stop with immediate cancellation

crates/irtt-client/src/async_client.rs

@@ -93,8 +93,6 @@ pub(crate) struct AsyncOpenState {
     deadline: Option<Instant>,
     deadline_timer: Option<Pin<Box<time::Sleep>>>,
     request_submitted: bool,
-    stop_after_current_attempt: bool,
-    stopped_after_current_attempt: bool,
     buffer: [u8; MAX_OPEN_PACKET_SIZE],
     cleanup: Option<AsyncOpenCleanup>,
 }
@@ -106,8 +104,6 @@ impl AsyncOpenState {
             deadline: None,
             deadline_timer: None,
             request_submitted: false,
-            stop_after_current_attempt: false,
-            stopped_after_current_attempt: false,
             buffer: [0_u8; MAX_OPEN_PACKET_SIZE],
             cleanup: None,
         }
@@ -128,21 +124,12 @@ impl AsyncOpenState {
         self.deadline = None;
         self.deadline_timer = None;
         self.request_submitted = false;
-        self.stopped_after_current_attempt = self.stop_after_current_attempt;
     }
 
     pub(crate) fn has_in_flight_work(&self) -> bool {
         self.request_submitted || self.cleanup.is_some()
     }
 
-    pub(crate) fn request_stop_after_current_attempt(&mut self) {
-        self.stop_after_current_attempt = true;
-    }
-
-    pub(crate) fn stopped_after_current_attempt(&self) -> bool {
-        self.stopped_after_current_attempt
-    }
-
     fn deadline(&self) -> Instant {
         self.deadline
             .expect("an open attempt has an active deadline")
@@ -324,10 +311,6 @@ impl AsyncClient {
             if state.attempt >= attempt_count {
                 return Poll::Ready(Err(ClientError::OpenTimeout));
             }
-            if state.stop_after_current_attempt && state.deadline.is_none() {
-                state.stopped_after_current_attempt = true;
-                return Poll::Ready(Err(ClientError::OpenTimeout));
-            }
             if state.deadline.is_none() {
                 let timeout = self.machine.config().open.timeouts[state.attempt];
                 if let Err(error) = state.start_attempt(timeout) {
@@ -368,9 +351,6 @@ impl AsyncClient {
                 Poll::Ready(Err(error)) => return Poll::Ready(Err(error)),
                 Poll::Ready(Ok(false)) => {
                     state.finish_attempt();
-                    if state.stopped_after_current_attempt() {
-                        return Poll::Ready(Err(ClientError::OpenTimeout));
-                    }
                     continue;
                 }
                 Poll::Ready(Ok(true)) => {}
@@ -396,9 +376,6 @@ impl AsyncClient {
             };
             if datagram.received_at.mono > state.deadline() {
                 state.finish_attempt();
-                if state.stopped_after_current_attempt() {
-                    return Poll::Ready(Err(ClientError::OpenTimeout));
-                }
                 continue;
             }
 
@@ -778,6 +755,16 @@ impl AsyncClient {
         .map_err(ClientError::Socket)
     }
 
+    /// Cancel opening without waiting for a reply or socket writability.
+    /// Retained post-token cleanup gets one best-effort nonblocking send.
+    pub(crate) fn cancel_open(&self, state: &mut AsyncOpenState) -> Option<ClientError> {
+        let cleanup = state.cleanup.take()?;
+        if let Some(packet) = cleanup.packet() {
+            let _ = self.socket.try_send(packet);
+        }
+        Some(cleanup.into_primary())
+    }
+
     fn poll_open_cleanup(
         &self,
         state: &mut AsyncOpenState,

crates/irtt-client/src/managed/task/target.rs

@@ -409,12 +409,12 @@ impl ManagedClientTask {
                     let retirement = retirement
                         .clone()
                         .unwrap_or(ManagedTargetEndReason::Stopped);
-                    if !open.has_in_flight_work() {
-                        self.targets[index].sync_live_packets_sent();
-                        self.finish_target(index, retirement, None);
-                        return false;
-                    }
-                    open.request_stop_after_current_attempt();
+                    let cleanup_failure = client.cancel_open(open).map(|error| {
+                        classify_client_error(ManagedTargetFailurePhase::Opening, &error)
+                    });
+                    self.targets[index].sync_live_packets_sent();
+                    self.finish_target(index, retirement, cleanup_failure);
+                    return false;
                 }
                 match client.poll_open(open, cx) {
                     Poll::Pending => false,
@@ -438,64 +438,25 @@ impl ManagedClientTask {
                             index,
                             vec![ClientEvent::SessionStarted(started)],
                         );
-                        if stopping {
-                            self.targets[index].sync_live_packets_sent();
-                            self.begin_drain(
-                                index,
-                                retirement
-                                    .clone()
-                                    .unwrap_or(ManagedTargetEndReason::Stopped),
-                                now,
-                            )
-                        } else {
-                            let previous = self.targets[index].take_phase();
-                            self.targets[index].restore_phase(TargetPhase::Active {
-                                client: previous.into_client(),
-                                schedule,
-                                send_waiting: false,
-                            });
-                            self.publish_target_phase(index, ManagedTargetLifecycle::Opening);
-                            true
-                        }
+                        let previous = self.targets[index].take_phase();
+                        self.targets[index].restore_phase(TargetPhase::Active {
+                            client: previous.into_client(),
+                            schedule,
+                            send_waiting: false,
+                        });
+                        self.publish_target_phase(index, ManagedTargetLifecycle::Opening);
+                        true
                     }
                     Poll::Ready(Ok(OpenOutcome::NoTestCompleted(completed))) => {
                         self.publish_client_events(
                             index,
                             vec![ClientEvent::NoTestCompleted(completed)],
                         );
-                        let end_reason = if stopping {
-                            retirement
-                                .clone()
-                                .unwrap_or(ManagedTargetEndReason::Stopped)
-                        } else {
-                            ManagedTargetEndReason::NoTestComplete
-                        };
-                        self.finish_target(index, end_reason, None);
+                        self.finish_target(index, ManagedTargetEndReason::NoTestComplete, None);
                         false
                     }
                     Poll::Ready(Err(error)) => {
-                        if stopping {
-                            let TargetPhase::Opening { open, .. } = self.targets[index].phase()
-                            else {
-                                unreachable!()
-                            };
-                            let cleanup_failure =
-                                (!open.stopped_after_current_attempt()).then(|| {
-                                    classify_client_error(
-                                        ManagedTargetFailurePhase::Opening,
-                                        &error,
-                                    )
-                                });
-                            self.finish_target(
-                                index,
-                                retirement
-                                    .clone()
-                                    .unwrap_or(ManagedTargetEndReason::Stopped),
-                                cleanup_failure,
-                            );
-                        } else {
-                            self.fail_target(index, ManagedTargetFailurePhase::Opening, error);
-                        }
+                        self.fail_target(index, ManagedTargetFailurePhase::Opening, error);
                         false
                     }
                 }