fix: improve daemon lifecycle (#2360)

See b/534287578

src/daemon/client.ts

@@ -143,6 +143,11 @@ export async function sendCommand(
   sessionId: string,
   timeout = SEND_COMMAND_TIMEOUT,
 ): Promise<DaemonResponse> {
+  // Before connecting and sending, verify the daemon is still alive.
+  if (!isDaemonRunning(sessionId)) {
+    throw new Error('Daemon is not running.');
+  }
+
   const socketPath = getSocketPath(sessionId);
 
   const socket = net.createConnection({

src/daemon/daemon.ts

@@ -262,7 +262,7 @@ async function startSocketServer() {
   });
 }
 
-async function cleanup() {
+async function cleanup(exitCode = 0) {
   console.log('Cleaning up daemon...');
 
   try {
@@ -291,7 +291,7 @@ async function cleanup() {
   if (fs.existsSync(pidFilePath)) {
     fs.unlinkSync(pidFilePath);
   }
-  process.exit(0);
+  process.exit(exitCode);
 }
 
 // Handle shutdown signals
@@ -308,13 +308,15 @@ process.on('SIGHUP', () => {
 // Handle uncaught errors
 process.on('uncaughtException', error => {
   logger?.('Uncaught exception:', error);
+  void cleanup(1);
 });
 process.on('unhandledRejection', error => {
   logger?.('Unhandled rejection:', error);
+  void cleanup(1);
 });
 
 // Start the server
 const started = startSocketServer().catch(error => {
   logger?.('Failed to start daemon server:', error);
-  process.exit(1);
+  void cleanup(1);
 });

src/daemon/utils.ts

@@ -26,13 +26,15 @@ export const DAEMON_CLIENT_NAME = 'chrome-devtools-cli-daemon';
 // Using these paths due to strict limits on the POSIX socket path length.
 export function getSocketPath(sessionId: string): string {
   const uid = os.userInfo().uid;
+  const username = os.userInfo().username;
   const suffix = sessionId ? `-${sessionId}` : '';
   const appName = APP_NAME + suffix;
 
   if (IS_WINDOWS) {
     // Windows uses Named Pipes, not file paths.
     // This format is required for server.listen()
-    return path.join('\\\\.\\pipe', appName, 'server.sock');
+    // Append username to prevent cross-user named pipe squatting
+    return path.join('\\\\.\\pipe', `${appName}-${username}`, 'server.sock');
   }
 
   // 1. Try XDG_RUNTIME_DIR (Linux standard, sometimes macOS)