artiq_devtool: more robust port forwarding.

artiq/frontend/artiq_devtool.py

@@ -105,6 +105,7 @@ def main():
         elif action == "connect":
             def forwarder(port):
                 listener = socket.socket()
+                listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
                 listener.bind(('localhost', port))
                 listener.listen(1)
                 while True:
@@ -114,6 +115,7 @@ def main():
                     remote_stream = get_ssh().get_transport() \
                         .open_channel('direct-tcpip', (args.ip, port), peer_addr)
                     while True:
+                        try:
                             r, w, x = select.select([local_stream, remote_stream], [], [])
                             if local_stream in r:
                                 data = local_stream.recv(1024)
@@ -125,6 +127,10 @@ def main():
                                 if data == b"":
                                     break
                                 local_stream.send(data)
+                        except Exception as e:
+                            logger.exception("Forward error on port %s", port)
+                    local_stream.close()
+                    remote_stream.close()
 
             for port in (1381, 1382):
                 thread = threading.Thread(target=forwarder, args=(port,),