The Tor Browser / file revision

 const CC = Components.Constructor;

 const Cc = Components.classes;

 const Ci = Components.interfaces;

 const BinaryInputStream = CC("@mozilla.org/binaryinputstream;1",

                              "nsIBinaryInputStream",

                              "setInputStream");

 const ProtocolProxyService = CC("@mozilla.org/network/protocol-proxy-service;1",

                                 "nsIProtocolProxyService");

 var sts = Cc["@mozilla.org/network/socket-transport-service;1"]

           .getService(Ci.nsISocketTransportService);

 function launchConnection(socks_vers, socks_port, dest_host, dest_port, dns)

 {

   var pi_flags = 0;

   if (dns == 'remote')

     pi_flags = Ci.nsIProxyInfo.TRANSPARENT_PROXY_RESOLVES_HOST;

   var pps = new ProtocolProxyService();

   var pi = pps.newProxyInfo(socks_vers, 'localhost', socks_port,

           pi_flags, -1, null);

   var trans = sts.createTransport(null, 0, dest_host, dest_port, pi);

   var input = trans.openInputStream(Ci.nsITransport.OPEN_BLOCKING,0,0);

   var output = trans.openOutputStream(Ci.nsITransport.OPEN_BLOCKING,0,0);

   var bin = new BinaryInputStream(input);

   var data = bin.readBytes(5);

   if (data == 'PING!') {

     print('client: got ping, sending pong.');

     output.write('PONG!', 5);

   } else {

     print('client: wrong data from server:', data);

     output.write('Error: wrong data received.', 27);

   }

   output.close();

 }

 for each (var arg in arguments) {

   print('client: running test', arg);

   test = arg.split('|');

   launchConnection(test[0], parseInt(test[1]), test[2],

        parseInt(test[3]), test[4]);

 }