Take boxed connection ID generator factories

When we store a type-erased, boxed value internally, accepting that
value directly allows users to avoid double-boxing. Probably not hugely
important in this case, but we've been adopting this pattern everywhere
else and we should be consistent.

quinn-proto/src/config/mod.rs

@@ -74,11 +74,11 @@ impl EndpointConfig {
     /// information in local connection IDs, e.g. to support stateless packet-level load balancers.
     ///
     /// Defaults to [`HashedConnectionIdGenerator`].
-    pub fn cid_generator<F: Fn() -> Box<dyn ConnectionIdGenerator> + Send + Sync + 'static>(
+    pub fn cid_generator(
         &mut self,
-        factory: F,
+        factory: Arc<dyn Fn() -> Box<dyn ConnectionIdGenerator> + Send + Sync>,
     ) -> &mut Self {
-        self.connection_id_generator_factory = Arc::new(factory);
+        self.connection_id_generator_factory = factory;
         self
     }
 

quinn-proto/src/tests/mod.rs

@@ -188,7 +188,9 @@ fn server_stateless_reset() {
     rng.fill_bytes(&mut key_material);
 
     let mut endpoint_config = EndpointConfig::new(Arc::new(reset_key));
-    endpoint_config.cid_generator(move || Box::new(HashedConnectionIdGenerator::from_key(0)));
+    endpoint_config.cid_generator(Arc::new(move || {
+        Box::new(HashedConnectionIdGenerator::from_key(0))
+    }));
     let endpoint_config = Arc::new(endpoint_config);
 
     let mut pair = Pair::new(endpoint_config.clone(), server_config());
@@ -217,7 +219,9 @@ fn client_stateless_reset() {
     rng.fill_bytes(&mut key_material);
 
     let mut endpoint_config = EndpointConfig::new(Arc::new(reset_key));
-    endpoint_config.cid_generator(move || Box::new(HashedConnectionIdGenerator::from_key(0)));
+    endpoint_config.cid_generator(Arc::new(move || {
+        Box::new(HashedConnectionIdGenerator::from_key(0))
+    }));
     let endpoint_config = Arc::new(endpoint_config);
 
     let mut pair = Pair::new(endpoint_config.clone(), server_config());
@@ -245,7 +249,9 @@ fn stateless_reset_limit() {
     let _guard = subscribe();
     let remote = SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 42);
     let mut endpoint_config = EndpointConfig::default();
-    endpoint_config.cid_generator(move || Box::new(RandomConnectionIdGenerator::new(8)));
+    endpoint_config.cid_generator(Arc::new(move || {
+        Box::new(RandomConnectionIdGenerator::new(8))
+    }));
     let endpoint_config = Arc::new(endpoint_config);
     let mut endpoint = Endpoint::new(
         endpoint_config.clone(),

quinn/src/tests.rs

@@ -826,7 +826,7 @@ async fn multiple_conns_with_zero_length_cids() {
     let mut factory = EndpointFactory::new();
     factory
         .endpoint_config
-        .cid_generator(|| Box::new(RandomConnectionIdGenerator::new(0)));
+        .cid_generator(Arc::new(|| Box::new(RandomConnectionIdGenerator::new(0))));
     let server = {
         let _guard = error_span!("server").entered();
         factory.endpoint()