fix: single thread for entire signal lifecycle — runtime never dropped (libcrypto TLS fix)

crates/wzp-android/src/jni_bridge.rs

@@ -413,24 +413,12 @@ pub unsafe extern "system" fn Java_com_wzp_engine_SignalManager_nativeSignalConn
     let relay: String = env.get_string(&relay_j).map(|s| s.into()).unwrap_or_default();
     let seed: String = env.get_string(&seed_j).map(|s| s.into()).unwrap_or_default();
 
-    // start() connects + registers synchronously (blocks briefly).
-    // Then we spawn run() on a thread for the recv loop.
+    // start() spawns an internal thread (connect+register+recv, ONE runtime, never dropped).
+    // Blocks up to 10s waiting for the connect+register to complete.
     match crate::signal_mgr::SignalManager::start(&relay, &seed) {
         Ok(mgr) => {
             let handle = Box::new(SignalHandle { mgr });
-            let raw = Box::into_raw(handle);
-
-            // Spawn recv loop on a small thread (no crypto init, just recv)
-            let recv_ref: &'static SignalHandle = unsafe { &*raw };
-            std::thread::Builder::new()
-                .name("wzp-signal-recv".into())
-                .stack_size(2 * 1024 * 1024) // 2MB is enough for recv-only
-                .spawn(move || {
-                    recv_ref.mgr.run();
-                })
-                .ok();
-
-            raw as jlong
+            Box::into_raw(handle) as jlong
         }
         Err(e) => {
             error!("signal connect failed: {e}");

crates/wzp-android/src/signal_mgr.rs

@@ -38,8 +38,9 @@ pub struct SignalManager {
 }
 
 impl SignalManager {
-    /// Connect to relay and register. Returns immediately with Self.
-    /// Then call `run()` on a separate thread to start the recv loop.
+    /// Create SignalManager and start connect+register+recv on a background thread.
+    /// Returns immediately. The internal thread runs forever.
+    /// CRITICAL: tokio runtime must never be dropped on Android (libcrypto TLS conflict).
     pub fn start(relay_addr: &str, seed_hex: &str) -> Result<Self, anyhow::Error> {
         let addr: SocketAddr = relay_addr.parse()?;
         let seed = if seed_hex.is_empty() {
@@ -52,66 +53,79 @@ impl SignalManager {
         let identity_pub = *pub_id.signing.as_bytes();
         let fp = pub_id.fingerprint.to_string();
 
-        info!(fingerprint = %fp, relay = %addr, "signal: connecting");
-
-        // Connect + register synchronously
-        let rt = tokio::runtime::Builder::new_current_thread()
-            .enable_all()
-            .build()?;
-
-        let transport = rt.block_on(async {
-            let bind: SocketAddr = "0.0.0.0:0".parse().unwrap();
-            let endpoint = wzp_transport::create_endpoint(bind, None)?;
-            let client_cfg = wzp_transport::client_config();
-            let conn = wzp_transport::connect(&endpoint, addr, "_signal", client_cfg).await?;
-            Ok::<_, anyhow::Error>(Arc::new(wzp_transport::QuinnTransport::new(conn)))
-        })?;
-
-        // Register presence (still on the same runtime)
-        rt.block_on(async {
-            transport.send_signal(&SignalMessage::RegisterPresence {
-                identity_pub,
-                signature: vec![],
-                alias: None,
-            }).await?;
-
-            match transport.recv_signal().await? {
-                Some(SignalMessage::RegisterPresenceAck { success: true, .. }) => {
-                    info!(fingerprint = %fp, "signal: registered");
-                    Ok(())
-                }
-                other => Err(anyhow::anyhow!("registration failed: {other:?}")),
-            }
-        })?;
-
-        // Don't drop runtime — keep it for run()
         let state = Arc::new(Mutex::new(SignalState {
-            status: "registered".into(),
-            fingerprint: fp,
+            status: "connecting".into(),
+            fingerprint: fp.clone(),
             ..Default::default()
         }));
         let running = Arc::new(AtomicBool::new(true));
 
-        Ok(Self {
-            transport,
-            state,
-            running,
-        })
-    }
+        // Channel to receive transport after connect succeeds
+        let (transport_tx, transport_rx) = std::sync::mpsc::channel();
 
-    /// Blocking recv loop. Run on a dedicated thread after start().
-    /// Never returns until the connection drops or stop() is called.
-    pub fn run(&self) {
-        let rt = tokio::runtime::Builder::new_current_thread()
-            .enable_all()
-            .build()
-            .expect("tokio runtime");
+        let bg_state = Arc::clone(&state);
+        let bg_running = Arc::clone(&running);
+        let ret_state = Arc::clone(&state);
+        let ret_running = Arc::clone(&running);
 
-        let transport = self.transport.clone();
-        let state = self.state.clone();
-        let running = self.running.clone();
+        // ONE thread, ONE runtime, NEVER dropped.
+        // Connect + register + recv loop all happen here.
+        std::thread::Builder::new()
+            .name("wzp-signal".into())
+            .stack_size(4 * 1024 * 1024)
+            .spawn(move || {
+                let rt = tokio::runtime::Builder::new_current_thread()
+                    .enable_all()
+                    .build()
+                    .expect("tokio runtime");
 
-        rt.block_on(async move {
+                rt.block_on(async move {
+                    info!(fingerprint = %fp, relay = %addr, "signal: connecting");
+
+                    let bind: SocketAddr = "0.0.0.0:0".parse().unwrap();
+                    let endpoint = match wzp_transport::create_endpoint(bind, None) {
+                        Ok(e) => e,
+                        Err(e) => {
+                            error!("signal endpoint: {e}");
+                            bg_state.lock().unwrap().status = "idle".into();
+                            return;
+                        }
+                    };
+                    let client_cfg = wzp_transport::client_config();
+                    let conn = match wzp_transport::connect(&endpoint, addr, "_signal", client_cfg).await {
+                        Ok(c) => c,
+                        Err(e) => {
+                            error!("signal connect: {e}");
+                            bg_state.lock().unwrap().status = "idle".into();
+                            return;
+                        }
+                    };
+                    let transport = Arc::new(wzp_transport::QuinnTransport::new(conn));
+
+                    // Register
+                    if let Err(e) = transport.send_signal(&SignalMessage::RegisterPresence {
+                        identity_pub, signature: vec![], alias: None,
+                    }).await {
+                        error!("signal register: {e}");
+                        bg_state.lock().unwrap().status = "idle".into();
+                        return;
+                    }
+
+                    match transport.recv_signal().await {
+                        Ok(Some(SignalMessage::RegisterPresenceAck { success: true, .. })) => {
+                            info!(fingerprint = %fp, "signal: registered");
+                            bg_state.lock().unwrap().status = "registered".into();
+                            // Send transport to caller
+                            let _ = transport_tx.send(transport.clone());
+                        }
+                        other => {
+                            error!("signal registration failed: {other:?}");
+                            bg_state.lock().unwrap().status = "idle".into();
+                            return;
+                        }
+                    }
+
+                    // Recv loop — runs forever
             loop {
                 if !running.load(Ordering::Relaxed) { break; }
 
@@ -163,9 +177,20 @@ impl SignalManager {
                 }
             }
 
-            let mut s = state.lock().unwrap();
-            s.status = "idle".into();
-        }); // block_on
+            bg_state.lock().unwrap().status = "idle".into();
+                }); // block_on
+
+                // Runtime intentionally NOT dropped — lives until thread exits.
+                // This prevents ring/libcrypto TLS cleanup conflict on Android.
+                // The thread is parked here forever (block_on returned = connection lost).
+                std::thread::park();
+            })?; // thread spawn
+
+        // Wait for transport (up to 10s)
+        let transport = transport_rx.recv_timeout(std::time::Duration::from_secs(10))
+            .map_err(|_| anyhow::anyhow!("signal connect timeout — check relay address"))?;
+
+        Ok(Self { transport, state: ret_state, running: ret_running })
     }
 
     /// Get current state (non-blocking).