Devices: the app waits for its old server before starting the new one; clipboard sends keep their headset (review round 31)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

app/main.js

@@ -154,10 +154,16 @@ async function startServer() {
 
 // Closing stdin lets server.py close its SSH connections and exit (the only clean
 // way on Windows); SIGTERM does the same elsewhere.
+// Resolves once it has exited (or after 20 s), so a replacement can take the server
+// lock: server.py allows one per user.
 function endServer(child) {
+  const gone = child.exitCode !== null || child.signalCode !== null ? Promise.resolve()
+    : new Promise((resolve) => child.once("exit", resolve));
   try { child.stdin.end(); } catch {}
   if (!IS_WIN) child.kill("SIGTERM");
-  setTimeout(() => { if (child.exitCode === null && child.signalCode === null) child.kill(); }, 5000).unref();
+  // server.py ignores a second SIGTERM while it shuts down, so the fallback is a hard kill.
+  setTimeout(() => { if (child.exitCode === null && child.signalCode === null) child.kill("SIGKILL"); }, 12000).unref();
+  return Promise.race([gone, new Promise((resolve) => setTimeout(resolve, 20000).unref())]);
 }
 
 function stopServer() {
@@ -182,7 +188,7 @@ async function restartServer() {
   const old = server;
   server = null;
   url = null;
-  if (old) endServer(old);
+  if (old) await endServer(old);
   await load();
 }
 

tests/test_server.py

@@ -248,7 +248,8 @@ class OneServer(unittest.TestCase):
 
     def test_a_second_server_is_refused_until_the_first_exits(self):
         data = tempfile.mkdtemp(prefix="frame-one-server-")
-        env = {**os.environ, "FRAME_CONTROL_DATA_DIR": data, "FRAME_ALIAS": "frame-control-test.invalid"}
+        env = {**os.environ, "FRAME_CONTROL_DATA_DIR": data, "FRAME_ALIAS": "frame-control-test.invalid",
+               "FRAME_CONTROL_SERVER_WAIT": "1"}
         first = self.start(env)
         self.assertIn("Frame Control on", first.stdout.readline())
         second = subprocess.run([sys.executable, str(ROOT / "ui" / "server.py"), "--port", "0"], env=env,

ui/index.html

@@ -1503,9 +1503,10 @@ $("clipSend").onclick = () => {
 // In the app, Electron reads the clipboard; in a browser, the server does.
 async function sendComputerClipboard() {
   if (!window.frameApp) return api("/api/clipboard", { fromComputer: true });
+  const device = window.connDevice;  // the headset it was sent to, not one switched to while reading
   const text = await window.frameApp.readClipboard();
   if (!text) throw new Error("The clipboard is empty (or holds something other than text)");
-  return api("/api/clipboard", { text });
+  return api("/api/clipboard", { text }, device);
 }
 $("clipMac").onclick = () => act($("clipMac").textContent, sendComputerClipboard, $("clipMac"));
 

ui/server.py

@@ -1662,7 +1662,7 @@ def one_server():
     edit the headsets on their own, and could move each other's installs to another
     headset. Held until this process exits. (FRAME_CONTROL_DATA_DIR gives a second,
     separate one, as the tests do.)"""
-    lock = frame_devices.file_lock(frame_host.data_dir("server.lock"), timeout=8)  # the app restarting its server
+    lock = frame_devices.file_lock(frame_host.data_dir("server.lock"), timeout=float(os.environ.get("FRAME_CONTROL_SERVER_WAIT") or 20))  # while the app restarts it
     try:
         lock.__enter__()
     except OSError: