From 87304744adee6a9e165b86735ed5f0b4420949b7 Mon Sep 17 00:00:00 2001
From: Ferdinand Schober <ferdinand.schober@fau.de>
Date: Thu, 10 Oct 2024 17:15:34 +0200
Subject: [PATCH] fix release logic

---
 src/capture.rs   | 14 +++++---------
 src/emulation.rs |  3 ++-
 src/service.rs   | 11 ++++++++---
 3 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/src/capture.rs b/src/capture.rs
index 3a9e04e..0f4bdfa 100644
--- a/src/capture.rs
+++ b/src/capture.rs
@@ -128,7 +128,7 @@ async fn do_capture(
         capture.create(handle, to_capture_pos(pos)).await?;
     }
 
-    let mut state = State::Receiving;
+    let mut state = State::WaitingForAck;
 
     loop {
         tokio::select! {
@@ -152,7 +152,10 @@ async fn do_capture(
                         state = State::Sending;
                     }
                     // client disconnected
-                    ProtoEvent::Leave(_) => release_capture(&mut capture, server).await?,
+                    ProtoEvent::Leave(_) => {
+                        log::info!("releasing capture: Server notified Leave");
+                        release_capture(&mut capture, server).await?;
+                    },
                     _ => {}
                 }
             },
@@ -197,7 +200,6 @@ macro_rules! debounce {
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 enum State {
-    Receiving,
     WaitingForAck,
     Sending,
 }
@@ -213,12 +215,6 @@ async fn handle_capture_event(
     let (handle, event) = event;
     log::trace!("({handle}): {event:?}");
 
-    if server.should_release.borrow_mut().take().is_some() && *state != State::Receiving {
-        log::info!("releasing capture: a client entered the device");
-        *state = State::Receiving;
-        return release_capture(capture, server).await;
-    }
-
     if capture.keys_pressed(&server.config.release_bind) {
         log::info!("releasing capture: release-bind pressed");
         return release_capture(capture, server).await;
diff --git a/src/emulation.rs b/src/emulation.rs
index 3dff0d9..dbdf7f0 100644
--- a/src/emulation.rs
+++ b/src/emulation.rs
@@ -53,7 +53,7 @@ impl Emulation {
                     match event {
                         ProtoEvent::Enter(pos) => {
                             if let Some(cert) = listener.get_certificate_fingerprint(addr).await {
-                                log::info!("{addr} entered this device");
+                                log::info!("releasing capture: {addr} entered this device");
                                 service.release_capture();
                                 listener.reply(addr, ProtoEvent::Ack(0)).await;
                                 service.register_incoming(addr, to_ipc_pos(pos), cert);
@@ -69,6 +69,7 @@ impl Emulation {
                     }
                 }
                 addr = release_rx.recv() => {
+                    // notify the other end that we hit a barrier (should release capture)
                     let addr = addr.expect("channel closed");
                     listener.reply(addr, ProtoEvent::Leave(0)).await;
                 }
diff --git a/src/service.rs b/src/service.rs
index e0d6394..2dcc438 100644
--- a/src/service.rs
+++ b/src/service.rs
@@ -75,7 +75,6 @@ pub struct Service {
     pending_incoming: Rc<RefCell<VecDeque<IncomingEvent>>>,
     capture_status: Rc<Cell<Status>>,
     pub(crate) emulation_status: Rc<Cell<Status>>,
-    pub(crate) should_release: Rc<RefCell<Option<ReleaseToken>>>,
     incoming_conns: Rc<RefCell<HashMap<ClientHandle, Incoming>>>,
     cert: Certificate,
     next_trigger_handle: u64,
@@ -89,6 +88,7 @@ struct Notifies {
     port_changed: Notify,
     frontend_event_pending: Notify,
     cancel: CancellationToken,
+    release: Notify,
 }
 
 impl Service {
@@ -136,7 +136,6 @@ impl Service {
             capture_status: Default::default(),
             emulation_status: Default::default(),
             incoming_conns: Rc::new(RefCell::new(HashMap::new())),
-            should_release: Default::default(),
             next_trigger_handle: 0,
         };
         Ok(service)
@@ -208,7 +207,13 @@ impl Service {
                         }
                     }
                 },
+                _ = self.notifies.release.notified() => {
+                    self.set_active(None);
+                    capture.release();
+                }
                 handle = capture.entered() => {
+                    // we entered the capture zone for an incoming connection
+                    // => notify it that its capture should be released
                     if let Some(incoming) = self.incoming_conns.borrow().get(&handle) {
                         emulation.notify_release(incoming.addr);
                     }
@@ -497,7 +502,7 @@ impl Service {
     }
 
     pub(crate) fn release_capture(&self) {
-        self.should_release.replace(Some(ReleaseToken));
+        self.notifies.release.notify_one();
     }
 
     pub(crate) fn set_active(&self, handle: Option<ClientHandle>) {