add --no-listen, for debugging

src/wormhole/blocking/transit.py

@@ -207,13 +207,14 @@ class RecordPipe:
         self.skt.close()
 
 class Common:
-    def __init__(self, transit_relay, timing=None):
+    def __init__(self, transit_relay, no_listen=False, timing=None):
         if transit_relay:
             if not isinstance(transit_relay, type(u"")):
                 raise UsageError
             self._transit_relays = [transit_relay]
         else:
             self._transit_relays = []
+        self._no_listen = no_listen
         self._timing = timing or DebugTiming()
         self._timing_started = self._timing.add_event("transit")
         self.winning = threading.Event()
@@ -224,6 +225,10 @@ class Common:
         self._start_server()
 
     def _start_server(self):
+        if self._no_listen:
+            self.my_direct_hints = []
+            self.listener = None
+            return
         server = MyTCPServer(("", 0), None)
         _, port = server.server_address
         self.my_direct_hints = [u"tcp:%s:%d" % (addr, port)

src/wormhole/scripts/cli_args.py

@@ -29,6 +29,8 @@ g.add_argument("--dump-timing", type=type(u""), # TODO: hide from --help output
                metavar="FILE", help="(debug) write timing data to file")
 g.add_argument("--twisted", action="store_true",
                help="use Twisted-based implementations, for testing")
+g.add_argument("--no-listen", action="store_true",
+               help="(debug) don't open a listening socket for Transit")
 parser.set_defaults(timing=None)
 subparsers = parser.add_subparsers(title="subcommands",
                                    dest="subcommand")

src/wormhole/scripts/cmd_receive_blocking.py

@@ -144,6 +144,7 @@ class BlockingReceiver:
     def establish_transit(self, w, them_d):
         transit_key = w.derive_key(APPID+u"/transit-key")
         transit_receiver = TransitReceiver(self.args.transit_helper,
+                                           no_listen=self.args.no_listen,
                                            timing=self.args.timing)
         transit_receiver.set_transit_key(transit_key)
         data = json.dumps({

src/wormhole/scripts/cmd_receive_twisted.py

@@ -99,6 +99,7 @@ class TwistedReceiver(BlockingReceiver):
     def establish_transit(self, w, them_d):
         transit_key = w.derive_key(APPID+u"/transit-key")
         transit_receiver = TransitReceiver(self.args.transit_helper,
+                                           no_listen=self.args.no_listen,
                                            timing=self.args.timing)
         transit_receiver.set_transit_key(transit_key)
         direct_hints = yield transit_receiver.get_direct_hints()

src/wormhole/scripts/cmd_send_blocking.py

@@ -18,7 +18,9 @@ def send_blocking(args):
           file=args.stdout)
 
     if fd_to_send is not None:
-        transit_sender = TransitSender(args.transit_helper, timing=args.timing)
+        transit_sender = TransitSender(args.transit_helper,
+                                       no_listen=args.no_listen,
+                                       timing=args.timing)
         transit_data = {
             "direct_connection_hints": transit_sender.get_direct_hints(),
             "relay_connection_hints": transit_sender.get_relay_hints(),

src/wormhole/scripts/cmd_send_twisted.py

@@ -45,7 +45,9 @@ def send_twisted(args):
     w = Wormhole(APPID, args.relay_url, timing=args.timing)
 
     if fd_to_send:
-        transit_sender = TransitSender(args.transit_helper, timing=args.timing)
+        transit_sender = TransitSender(args.transit_helper,
+                                       no_listen=args.no_listen,
+                                       timing=args.timing)
         phase1["transit"] = transit_data = {}
         transit_data["relay_connection_hints"] = transit_sender.get_relay_hints()
         direct_hints = yield transit_sender.get_direct_hints()

src/wormhole/twisted/transit.py

@@ -469,7 +469,8 @@ def there_can_be_only_one(contenders):
 class Common:
     RELAY_DELAY = 2.0
 
-    def __init__(self, transit_relay, reactor=reactor, timing=None):
+    def __init__(self, transit_relay, no_listen=False,
+                 reactor=reactor, timing=None):
         if transit_relay:
             if not isinstance(transit_relay, type(u"")):
                 raise UsageError
@@ -477,6 +478,7 @@ class Common:
         else:
             self._transit_relays = []
         self._transit_key = None
+        self._no_listen = no_listen
         self._waiting_for_transit_key = []
         self._listener = None
         self._winner = None
@@ -485,6 +487,8 @@ class Common:
         self._timing_started = self._timing.add_event("transit")
 
     def _build_listener(self):
+        if self._no_listen:
+            return ([], None)
         portnum = allocate_tcp_port()
         direct_hints = [u"tcp:%s:%d" % (addr, portnum)
                         for addr in ipaddrs.find_addresses()]