#2995 followups

lightning-background-processor/src/lib.rs

@@ -2318,8 +2318,8 @@ mod tests {
 
 		begin_open_channel!(nodes[0], nodes[1], channel_value);
 		assert_eq!(
-			first_event_recv.recv_timeout(Duration::from_secs(EVENT_DEADLINE)),
-			second_event_recv.recv_timeout(Duration::from_secs(EVENT_DEADLINE))
+			first_event_recv.recv_timeout(Duration::from_secs(EVENT_DEADLINE)).unwrap(),
+			second_event_recv.recv_timeout(Duration::from_secs(EVENT_DEADLINE)).unwrap()
 		);
 
 		if !std::thread::panicking() {

lightning/src/events/mod.rs

@@ -756,8 +756,9 @@ pub enum Event {
 	/// replies. Handlers should connect to the node otherwise any buffered messages may be lost.
 	///
 	/// # Failure Behavior and Persistence
-	/// This event will eventually be replayed after failures-to-handle (i.e., the event handler
-	/// returning `Err(ReplayEvent ())`), but won't be persisted across restarts.
+	/// This event won't be replayed after failures-to-handle
+	/// (i.e., the event handler returning `Err(ReplayEvent ())`), and also won't be persisted
+	/// across restarts.
 	///
 	/// [`OnionMessage`]: msgs::OnionMessage
 	/// [`MessageRouter`]: crate::onion_message::messenger::MessageRouter

lightning/src/onion_message/messenger.rs

@@ -1047,21 +1047,25 @@ where
 	}
 }
 
-macro_rules! drop_handled_events_and_abort { ($self: expr, $res: expr, $offset: expr, $event_queue: expr) => {
+macro_rules! drop_handled_events_and_abort { ($self: expr, $res_iter: expr, $event_queue: expr) => {
 	// We want to make sure to cleanly abort upon event handling failure. To this end, we drop all
 	// successfully handled events from the given queue, reset the events processing flag, and
 	// return, to have the events eventually replayed upon next invocation.
 	{
 		let mut queue_lock = $event_queue.lock().unwrap();
 
-		// We skip `$offset` result entries to reach the ones relevant for the given `$event_queue`.
-		let mut res_iter = $res.iter().skip($offset);
-
 		// Keep all events which previously error'd *or* any that have been added since we dropped
 		// the Mutex before.
-		queue_lock.retain(|_| res_iter.next().map_or(true, |r| r.is_err()));
+		let mut any_error = false;
+		queue_lock.retain(|_| {
+			$res_iter.next().map_or(true, |r| {
+				let is_err = r.is_err();
+				any_error |= is_err;
+				is_err
+			})
+		});
 
-		if $res.iter().any(|r| r.is_err()) {
+		if any_error {
 			// We failed handling some events. Return to have them eventually replayed.
 			$self.pending_events_processor.store(false, Ordering::Release);
 			$self.event_notifier.notify();
@@ -1426,7 +1430,8 @@ where
 			}
 			// Let the `OnionMessageIntercepted` events finish before moving on to peer_connecteds
 			let res = MultiResultFuturePoller::new(futures).await;
-			drop_handled_events_and_abort!(self, res, intercepted_msgs_offset, self.pending_intercepted_msgs_events);
+			let mut res_iter = res.iter().skip(intercepted_msgs_offset);
+			drop_handled_events_and_abort!(self, res_iter, self.pending_intercepted_msgs_events);
 		}
 
 		{
@@ -1449,7 +1454,8 @@ where
 					futures.push(future);
 				}
 				let res = MultiResultFuturePoller::new(futures).await;
-				drop_handled_events_and_abort!(self, res, 0, self.pending_peer_connected_events);
+				let mut res_iter = res.iter();
+				drop_handled_events_and_abort!(self, res_iter, self.pending_peer_connected_events);
 			}
 		}
 		self.pending_events_processor.store(false, Ordering::Release);
@@ -1508,7 +1514,7 @@ where
 		{
 			let pending_intercepted_msgs_events = self.pending_intercepted_msgs_events.lock().unwrap();
 			intercepted_msgs = pending_intercepted_msgs_events.clone();
-			let mut pending_peer_connected_events = self.pending_peer_connected_events.lock().unwrap();
+			let pending_peer_connected_events = self.pending_peer_connected_events.lock().unwrap();
 			peer_connecteds = pending_peer_connected_events.clone();
 			#[cfg(debug_assertions)] {
 				for ev in pending_intercepted_msgs_events.iter() {
@@ -1518,14 +1524,47 @@ where
 					if let Event::OnionMessagePeerConnected { .. } = ev {} else { panic!(); }
 				}
 			}
-			pending_peer_connected_events.shrink_to(10); // Limit total heap usage
 		}
 
-		let res = intercepted_msgs.into_iter().map(|ev| handler.handle_event(ev)).collect::<Vec<_>>();
-		drop_handled_events_and_abort!(self, res, 0, self.pending_intercepted_msgs_events);
+		let mut handling_intercepted_msgs_failed = false;
+		let mut num_handled_intercepted_events = 0;
+		for ev in intercepted_msgs {
+			match handler.handle_event(ev) {
+				Ok(()) => num_handled_intercepted_events += 1,
+				Err(ReplayEvent ()) => {
+					handling_intercepted_msgs_failed = true;
+					break;
+				}
+			}
+		}
+
+		{
+			let mut pending_intercepted_msgs_events = self.pending_intercepted_msgs_events.lock().unwrap();
+			pending_intercepted_msgs_events.drain(..num_handled_intercepted_events);
+		}
 
-		let res = peer_connecteds.into_iter().map(|ev| handler.handle_event(ev)).collect::<Vec<_>>();
-		drop_handled_events_and_abort!(self, res, 0, self.pending_peer_connected_events);
+		if handling_intercepted_msgs_failed {
+			self.pending_events_processor.store(false, Ordering::Release);
+			self.event_notifier.notify();
+			return;
+		}
+
+		let mut num_handled_peer_connecteds = 0;
+		for ev in peer_connecteds {
+			match handler.handle_event(ev) {
+				Ok(()) => num_handled_peer_connecteds += 1,
+				Err(ReplayEvent ()) => {
+					self.event_notifier.notify();
+					break;
+				}
+			}
+		}
+
+		{
+			let mut pending_peer_connected_events = self.pending_peer_connected_events.lock().unwrap();
+			pending_peer_connected_events.drain(..num_handled_peer_connecteds);
+			pending_peer_connected_events.shrink_to(10); // Limit total heap usage
+		}
 
 		self.pending_events_processor.store(false, Ordering::Release);
 	}