From d75948953097eb7278a521b83e6cd011634fd0c9 Mon Sep 17 00:00:00 2001
From: Nick Mathewson <nickm@torproject.org>
Date: Wed, 12 Oct 2022 10:11:43 -0400
Subject: [PATCH] Allow multiple ChannelBuilders to share a ChanMgrEventSender.

---
 crates/tor-chanmgr/src/builder.rs | 12 ++++++++----
 crates/tor-chanmgr/src/lib.rs     |  1 +
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/crates/tor-chanmgr/src/builder.rs b/crates/tor-chanmgr/src/builder.rs
index ce00087fd..45442337d 100644
--- a/crates/tor-chanmgr/src/builder.rs
+++ b/crates/tor-chanmgr/src/builder.rs
@@ -36,7 +36,7 @@ where
     /// Asynchronous runtime for TLS, TCP, spawning, and timeouts.
     runtime: R,
     /// Used to update our bootstrap reporting status.
-    event_sender: Mutex<ChanMgrEventSender>,
+    event_sender: Arc<Mutex<ChanMgrEventSender>>,
     /// The transport object that we use to construct streams.
     transport: H,
     /// Object to build TLS connections.
@@ -48,12 +48,16 @@ where
     R: TlsProvider<H::Stream>,
 {
     /// Construct a new ChanBuilder.
-    pub(crate) fn new(runtime: R, transport: H, event_sender: ChanMgrEventSender) -> Self {
+    pub(crate) fn new(
+        runtime: R,
+        transport: H,
+        event_sender: Arc<Mutex<ChanMgrEventSender>>,
+    ) -> Self {
         let tls_connector = <R as TlsProvider<H::Stream>>::tls_connector(&runtime);
         ChanBuilder {
             runtime,
             transport,
-            event_sender: Mutex::new(event_sender),
+            event_sender,
             tls_connector,
         }
     }
@@ -432,7 +436,7 @@ mod test {
             // Create the channel builder that we want to test.
             let (snd, _rcv) = crate::event::channel();
             let transport = DefaultTransport::new(client_rt.clone());
-            let builder = ChanBuilder::new(client_rt, transport, snd);
+            let builder = ChanBuilder::new(client_rt, transport, Arc::new(Mutex::new(snd)));
 
             let (r1, r2): (Result<Channel>, Result<LocalStream>) = futures::join!(
                 async {
diff --git a/crates/tor-chanmgr/src/lib.rs b/crates/tor-chanmgr/src/lib.rs
index 131b4e484..b7bb60c1a 100644
--- a/crates/tor-chanmgr/src/lib.rs
+++ b/crates/tor-chanmgr/src/lib.rs
@@ -197,6 +197,7 @@ impl<R: Runtime> ChanMgr<R> {
         R: 'static,
     {
         let (sender, receiver) = event::channel();
+        let sender = Arc::new(std::sync::Mutex::new(sender));
         let transport = builder::DefaultTransport::new(runtime.clone());
         let builder = builder::ChanBuilder::new(runtime.clone(), transport, sender);
         let builder = builder::TimeoutChannelFactory::new(runtime, builder);