Implement native UDP transport reliability (#52)

crates/libremetaverse/src/client_core.rs

@@ -113,6 +113,7 @@ struct ClientRuntime {
     state: AtomicU8,
     cancellation: CancellationTokenSource,
     services: Mutex<Vec<ServiceRegistration>>,
+    agent_throttle_sender: Mutex<Option<Arc<dyn crate::udp_transport::AgentThrottleSender>>>,
     shutdown_complete: Condvar,
     shutdown_wait: Mutex<()>,
 }
@@ -132,6 +133,7 @@ impl ClientRuntime {
                     })
                     .collect(),
             ),
+            agent_throttle_sender: Mutex::new(None),
             shutdown_complete: Condvar::new(),
             shutdown_wait: Mutex::new(()),
         }
@@ -200,6 +202,10 @@ impl ClientRuntime {
             }
         }
         services.clear();
+        self.agent_throttle_sender
+            .lock()
+            .unwrap_or_else(std::sync::PoisonError::into_inner)
+            .take();
         let shutdown_wait = self
             .shutdown_wait
             .lock()
@@ -257,6 +263,41 @@ impl GridClient {
         self.runtime.register(service)
     }
 
+    /// Installs the network-owned callback used by mapped `AgentThrottle.Set`.
+    ///
+    /// # Errors
+    ///
+    /// Registration fails after client shutdown begins.
+    pub fn set_agent_throttle_sender(
+        &mut self,
+        sender: Arc<dyn crate::udp_transport::AgentThrottleSender>,
+    ) -> Result<(), ClientCoreError> {
+        let mut registered = self
+            .runtime
+            .agent_throttle_sender
+            .lock()
+            .unwrap_or_else(std::sync::PoisonError::into_inner);
+        let state = self.lifecycle_state();
+        if state != ClientLifecycleState::Active {
+            return Err(ClientCoreError::InvalidLifecycle {
+                operation: "register the agent throttle sender",
+                state,
+            });
+        }
+        *registered = Some(sender);
+        Ok(())
+    }
+
+    pub(crate) fn agent_throttle_sender(
+        &self,
+    ) -> Option<Arc<dyn crate::udp_transport::AgentThrottleSender>> {
+        self.runtime
+            .agent_throttle_sender
+            .lock()
+            .unwrap_or_else(std::sync::PoisonError::into_inner)
+            .clone()
+    }
+
     pub(crate) fn shutdown(&self) -> Result<(), ClientCoreError> {
         self.runtime.shutdown()
     }