fixed unused() method to properly check sent packets

quiche/src/path.rs

@@ -324,11 +324,13 @@ impl Path {
 
     /// Returns whether the path is unused.
     #[inline]
-    fn unused(&self) -> bool {
-        // FIXME: we should check that there is nothing in the sent queue.
-        !self.active() && self.active_dcid_seq.is_none()
+    fn unused(&self) -> bool {  
+        // FIXME: we should check that there is nothing in the sent queue.  
+        !self.active() &&   
+        self.active_dcid_seq.is_none() &&   
+        self.recovery.bytes_in_flight_duration() == Duration::ZERO &&  
+        self.recovery.sent_packets_empty()  
     }
-
     /// Returns whether the path requires sending a probing packet.
     #[inline]
     pub fn probing_required(&self) -> bool {

quiche/src/recovery/congestion/recovery.rs

@@ -623,7 +623,6 @@ impl RecoveryOps for LegacyRecovery {
         }
 
         self.epochs[epoch].sent_packets.push_back(pkt);
-
         trace!("{trace_id} {self:?}");
     }
 
@@ -1042,6 +1041,10 @@ impl RecoveryOps for LegacyRecovery {
     fn bytes_lost(&self) -> u64 {
         self.bytes_lost
     }
+
+    fn sent_packets_empty(&self) -> bool {  
+        self.epochs.iter().all(|epoch| epoch.sent_packets.is_empty())  
+    }
 }
 
 impl std::fmt::Debug for LegacyRecovery {
@@ -1091,3 +1094,4 @@ pub struct Acked {
 
     pub is_app_limited: bool,
 }
+

quiche/src/recovery/gcongestion/recovery.rs

@@ -1168,6 +1168,9 @@ impl RecoveryOps for GRecovery {
             .min(64 * 1024)
             .max(floor as u64) as usize
     }
+    fn sent_packets_empty(&self) -> bool {  
+        self.epochs.iter().all(|epoch| epoch.sent_packets.is_empty())  
+    }
 }
 
 impl std::fmt::Debug for GRecovery {

quiche/src/recovery/mod.rs

@@ -183,7 +183,7 @@ pub struct OnLossDetectionTimeoutOutcome {
 pub trait RecoveryOps {
     fn lost_count(&self) -> usize;
     fn bytes_lost(&self) -> u64;
-
+    
     /// Returns whether or not we should elicit an ACK even if we wouldn't
     /// otherwise have constructed an ACK eliciting packet.
     fn should_elicit_ack(&self, epoch: packet::Epoch) -> bool;
@@ -315,6 +315,8 @@ pub trait RecoveryOps {
     fn get_next_release_time(&self) -> ReleaseDecision;
 
     fn gcongestion_enabled(&self) -> bool;
+
+    fn sent_packets_empty(&self) -> bool;
 }
 
 impl Recovery {