text: # -*- coding: utf-8 -*-
  #
  # Xlib.protocol.display -- core display communication
  #
  #    Copyright (C) 2000-2002 Peter Liljenberg <petli@ctrl-c.liu.se>
  #
  # This library is free software; you can redistribute it and/or
  # modify it under the terms of the GNU Lesser General Public License
  # as published by the Free Software Foundation; either version 2.1
  # of the License, or (at your option) any later version.
  #
  # This library is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  # See the GNU Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this library; if not, write to the
  #    Free Software Foundation, Inc.,
  #    59 Temple Place,
  #    Suite 330,
  #    Boston, MA 02111-1307 USA
  
  # Standard modules
  import errno
  import math
  import select
  import socket
  import struct
  import sys
  
  # Python 2/3 compatibility.
  from six import PY3, byte2int, indexbytes
  
  # Xlib modules
  from .. import error
  from ..ext import ge
  
  from ..support import lock, connect
  
  # Xlib.protocol modules
  from . import rq
  from . import event
  
  if PY3:
  
      class bytesview(object):
  
          def __init__(self, data, offset=0, size=None):
              if size is None:
                  size = len(data)-offset
              if isinstance(data, bytes):
                  view = memoryview(data)
              elif isinstance(data, bytesview):
                  view = data.view
              else:
                  raise TypeError('unsupported type: {}'.format(type(data)))
              self.view = view[offset:offset+size]
  
          def __len__(self):
              return len(self.view)
  
          def __getitem__(self, key):
              if isinstance(key, slice):
                  return bytes(self.view[key])
              return self.view[key]
  
  else:
  
      def bytesview(data, offset=0, size=None):
          if not isinstance(data, (bytes, buffer)):
              raise TypeError('unsupported type: {}'.format(type(data)))
          if size is None:
              size = len(data)-offset
          return buffer(data, offset, size)
  
  
  class Display(object):
      extension_major_opcodes = {}
      error_classes = error.xerror_class.copy()
      event_classes = event.event_class.copy()
  
      def __init__(self, display = None):
          name, protocol, host, displayno, screenno = connect.get_display(display)
  
          self.display_name = name
          self.default_screen = screenno
  
          self.socket = connect.get_socket(name, protocol, host, displayno)
  
          auth_name, auth_data = connect.get_auth(self.socket, name,
                                                  protocol, host, displayno)
  
          # Internal structures for communication, grouped
          # by their function and locks
  
          # Socket error indicator, set when the socket is closed
          # in one way or another
          self.socket_error_lock = lock.allocate_lock()
          self.socket_error = None
  
          # Event queue
          self.event_queue_read_lock = lock.allocate_lock()
          self.event_queue_write_lock = lock.allocate_lock()
          self.event_queue = []
  
          # Unsent request queue and sequence number counter
          self.request_queue_lock = lock.allocate_lock()
          self.request_serial = 1
          self.request_queue = []
  
          # Send-and-receive loop, see function send_and_receive
          # for a detailed explanation
          self.send_recv_lock = lock.allocate_lock()
          self.send_active = 0
          self.recv_active = 0
  
          self.event_waiting = 0
          self.event_wait_lock = lock.allocate_lock()
          self.request_waiting = 0
          self.request_wait_lock = lock.allocate_lock()
  
          # Calculate optimal default buffer size for recv.
          buffer_size = self.socket.getsockopt(socket.SOL_SOCKET,
                                               socket.SO_RCVBUF)
          buffer_size = math.pow(2, math.floor(math.log(buffer_size, 2)))
          self.recv_buffer_size = int(buffer_size)
  
          # Data used by the send-and-receive loop
          self.sent_requests = []
          self.recv_packet_len = 0
          self.data_send = b''
          self.data_recv = b''
          self.data_sent_bytes = 0
  
          # Resource ID structures
          self.resource_id_lock = lock.allocate_lock()
          self.resource_ids = {}
          self.last_resource_id = 0
  
          # Use an default error handler, one which just prints the error
          self.error_handler = None
  
  
          # Right, now we're all set up for the connection setup
          # request with the server.
  
          # Figure out which endianness the hardware uses
          self.big_endian = struct.unpack('BB', struct.pack('H', 0x0100))[0]
  
          if self.big_endian:
              order = 0x42
          else:
              order = 0x6c
  
          # Send connection setup
          r = ConnectionSetupRequest(self,
                                     byte_order = order,
                                     protocol_major = 11,
                                     protocol_minor = 0,
                                     auth_prot_name = auth_name,
                                     auth_prot_data = auth_data)
  
          # Did connection fail?
          if r.status != 1:
              raise error.DisplayConnectionError(self.display_name, r.reason)
  
          # Set up remaining info
          self.info = r
          self.default_screen = min(self.default_screen, len(self.info.roots) - 1)
  
  
      #
      # Public interface
      #
  
      def get_display_name(self):
          return self.display_name
  
      def get_default_screen(self):
          return self.default_screen
  
      def fileno(self):
          self.check_for_error()
          return self.socket.fileno()
  
      def next_event(self):
          self.check_for_error()
  
          # Main lock, so that only one thread at a time performs the
          # event waiting code.  This at least guarantees that the first
          # thread calling next_event() will get the next event, although
          # no order is guaranteed among other threads calling next_event()
          # while the first is blocking.
  
          self.event_queue_read_lock.acquire()
  
          # Lock event queue, so we can check if it is empty
          self.event_queue_write_lock.acquire()
  
          # We have too loop until we get an event, as
          # we might be woken up when there is no event.
  
          while not self.event_queue:
  
              # Lock send_recv so no send_and_receive
              # can start or stop while we're checking
              # whether there are one active.
              self.send_recv_lock.acquire()
  
              # Release event queue to allow an send_and_recv to
              # insert any now.
              self.event_queue_write_lock.release()
  
              # Call send_and_recv, which will return when
              # something has occured
              self.send_and_recv(event = 1)
  
              # Before looping around, lock the event queue against
              # modifications.
              self.event_queue_write_lock.acquire()
  
          # Whiew, we have an event!  Remove it from
          # the event queue and relaese its write lock.
  
          event = self.event_queue[0]
          del self.event_queue[0]
          self.event_queue_write_lock.release()
  
          # Finally, allow any other threads which have called next_event()
          # while we were waiting to proceed.
  
          self.event_queue_read_lock.release()
  
          # And return the event!
          return event
  
      def pending_events(self):
          self.check_for_error()
  
          # Make a send_and_recv pass, receiving any events
          self.send_recv_lock.acquire()
          self.send_and_recv(recv = 1)
  
          # Lock the queue, get the event count, and unlock again.
          self.event_queue_write_lock.acquire()
          count = len(self.event_queue)
          self.event_queue_write_lock.release()
  
          return count
  
      def flush(self):
          self.check_for_error()
          self.send_recv_lock.acquire()
          self.send_and_recv(flush = 1)
  
      def close(self):
          self.flush()
          self.close_internal('client')
  
      def set_error_handler(self, handler):
          self.error_handler = handler
  
  
      def allocate_resource_id(self):
          """id = d.allocate_resource_id()
  
          Allocate a new X resource id number ID.
  
          Raises ResourceIDError if there are no free resource ids.
          """
  
          self.resource_id_lock.acquire()
          try:
              i = self.last_resource_id
              while i in self.resource_ids:
                  i = i + 1
                  if i > self.info.resource_id_mask:
                      i = 0
                  if i == self.last_resource_id:
                      raise error.ResourceIDError('out of resource ids')
  
              self.resource_ids[i] = None
              self.last_resource_id = i
              return self.info.resource_id_base | i
          finally:
              self.resource_id_lock.release()
  
      def free_resource_id(self, rid):
          """d.free_resource_id(rid)
  
          Free resource id RID.  Attempts to free a resource id which
          isn't allocated by us are ignored.
          """
  
          self.resource_id_lock.acquire()
          try:
              i = rid & self.info.resource_id_mask
  
              # Attempting to free a resource id outside our range
              if rid - i != self.info.resource_id_base:
                  return None
  
              try:
                  del self.resource_ids[i]
              except KeyError:
                  pass
          finally:
              self.resource_id_lock.release()
  
  
  
      def get_resource_class(self, class_name, default = None):
          """class = d.get_resource_class(class_name, default = None)
  
          Return the class to be used for X resource objects of type
          CLASS_NAME, or DEFAULT if no such class is set.
          """
  
          return self.resource_classes.get(class_name, default)
  
      def set_extension_major(self, extname, major):
          self.extension_major_opcodes[extname] = major
  
      def get_extension_major(self, extname):
          return self.extension_major_opcodes[extname]
  
      def add_extension_event(self, code, evt, subcode=None):
         if subcode == None:
             self.event_classes[code] = evt
         else:
             if not code in self.event_classes:
                 self.event_classes[code] = {subcode: evt}
             else:
                 self.event_classes[code][subcode] = evt
  
      def add_extension_error(self, code, err):
          self.error_classes[code] = err
  
  
      #
      # Private functions
      #
  
      def check_for_error(self):
          self.socket_error_lock.acquire()
          err = self.socket_error
          self.socket_error_lock.release()
  
          if err:
              raise err
  
      def send_request(self, request, wait_for_response):
          if self.socket_error:
              raise self.socket_error
  
          self.request_queue_lock.acquire()
  
          request._serial = self.request_serial
          self.request_serial = (self.request_serial + 1) % 65536
  
          self.request_queue.append((request, wait_for_response))
          qlen = len(self.request_queue)
  
          self.request_queue_lock.release()
  
  #       if qlen > 10:
  #           self.flush()
  
      def close_internal(self, whom):
          # Clear out data structures
          self.request_queue = None
          self.sent_requests = None
          self.event_queue = None
          self.data_send = None
          self.data_recv = None
  
          # Close the connection
          self.socket.close()
  
          # Set a connection closed indicator
          self.socket_error_lock.acquire()
          self.socket_error = error.ConnectionClosedError(whom)
          self.socket_error_lock.release()
  
  
      def send_and_recv(self, flush = None, event = None, request = None, recv = None):
          """send_and_recv(flush = None, event = None, request = None, recv = None)
  
          Perform I/O, or wait for some other thread to do it for us.
  
          send_recv_lock MUST be LOCKED when send_and_recv is called.
          It will be UNLOCKED at return.
  
          Exactly or one of the parameters flush, event, request and recv must
          be set to control the return condition.
  
          To attempt to send all requests in the queue, flush should
          be true.  Will return immediately if another thread is
          already doing send_and_recv.
  
          To wait for an event to be received, event should be true.
  
          To wait for a response to a certain request (either an error
          or a response), request should be set the that request's
          serial number.
  
          To just read any pending data from the server, recv should be true.
  
          It is not guaranteed that the return condition has been
          fulfilled when the function returns, so the caller has to loop
          until it is finished.
          """
  
          # We go to sleep if there is already a thread doing what we
          # want to do:
  
          #  If flushing, we want to send
          #  If waiting for a response to a request, we want to send
          #    (to ensure that the request was sent - we alway recv
          #     when we get to the main loop, but sending is the important
          #     thing here)
          #  If waiting for an event, we want to recv
          #  If just trying to receive anything we can, we want to recv
  
          # FIXME: It would be good if we could also sleep when we're waiting on
          # a response to a request that has already been sent.
  
          if (((flush or request is not None) and self.send_active)
              or ((event or recv) and self.recv_active)):
  
              # Signal that we are waiting for something.  These locks
              # together with the *_waiting variables are used as
              # semaphores.  When an event or a request response arrives,
              # it will zero the *_waiting and unlock the lock.  The
              # locks will also be unlocked when an active send_and_recv
              # finishes to signal the other waiting threads that one of
              # them has to take over the send_and_recv function.
  
              # All this makes these locks and variables a part of the
              # send_and_recv control logic, and hence must be modified
              # only when we have the send_recv_lock locked.
              if event:
                  wait_lock = self.event_wait_lock
                  if not self.event_waiting:
                      self.event_waiting = 1
                      wait_lock.acquire()
  
              elif request is not None:
                  wait_lock = self.request_wait_lock
                  if not self.request_waiting:
                      self.request_waiting = 1
                      wait_lock.acquire()
  
              # Release send_recv, allowing a send_and_recive
              # to terminate or other threads to queue up
              self.send_recv_lock.release()
  
              # Return immediately if flushing, even if that
              # might mean that not necessarily all requests
              # have been sent.
              if flush or recv:
                  return
  
              # Wait for something to happen, as the wait locks are
              # unlocked either when what we wait for has arrived (not
              # necessarily the exact object we're waiting for, though),
              # or when an active send_and_recv exits.
  
              # Release it immediately afterwards as we're only using
              # the lock for synchonization.  Since we're not modifying
              # event_waiting or request_waiting here we don't have
              # to lock send_and_recv_lock.  In fact, we can't do that
              # or we trigger a dead-lock.
  
              wait_lock.acquire()
              wait_lock.release()
  
              # Return to caller to let it check whether it has
              # got the data it was waiting for
              return
  
  
          # There's no thread doing what we need to do.  Find out exactly
          # what to do
  
          # There must always be some thread receiving data, but it must not
          # necessarily be us
  
          if not self.recv_active:
              receiving = 1
              self.recv_active = 1
          else:
              receiving = 0
  
          flush_bytes = None
          sending = 0
  
          # Loop, receiving and sending data.
          while 1:
  
              # We might want to start sending data
              if sending or not self.send_active:
  
                  # Turn all requests on request queue into binary form
                  # and append them to self.data_send
  
                  self.request_queue_lock.acquire()
                  for req, wait in self.request_queue:
                      self.data_send = self.data_send + req._binary
                      if wait:
                          self.sent_requests.append(req)
  
                  del self.request_queue[:]
                  self.request_queue_lock.release()
  
                  # If there now is data to send, mark us as senders
  
                  if self.data_send:
                      self.send_active = 1
                      sending = 1
                  else:
                      self.send_active = 0
                      sending = 0
  
              # We've done all setup, so release the lock and start waiting
              # for the network to fire up
              self.send_recv_lock.release()
  
              # There's no longer anything useful we can do here.
              if not (sending or receiving):
                  break
  
              # If we're flushing, figure out how many bytes we
              # have to send so that we're not caught in an interminable
              # loop if other threads continuously append requests.
              if flush and flush_bytes is None:
                  flush_bytes = self.data_sent_bytes + len(self.data_send)
  
  
              try:
                  # We're only checking for the socket to be writable
                  # if we're the sending thread.  We always check for it
                  # to become readable: either we are the receiving thread
                  # and should take care of the data, or the receiving thread
                  # might finish receiving after having read the data
  
                  if sending:
                      writeset = [self.socket]
                  else:
                      writeset = []
  
                  # Timeout immediately if we're only checking for
                  # something to read or if we're flushing, otherwise block
  
                  if recv or flush:
                      timeout = 0
                  else:
                      timeout = None
  
                  rs, ws, es = select.select([self.socket], writeset, [], timeout)
  
              # Ignore errors caused by a signal received while blocking.
              # All other errors are re-raised.
              except select.error as err:
                  if isinstance(err, OSError):
                      code = err.errno
                  else:
                      code = err[0]
                  if code != errno.EINTR:
                      raise
  
                  # We must lock send_and_recv before we can loop to
                  # the start of the loop
  
                  self.send_recv_lock.acquire()
                  continue
  
  
              # Socket is ready for sending data, send as much as possible.
              if ws:
                  try:
                      i = self.socket.send(self.data_send)
                  except socket.error as err:
                      self.close_internal('server: %s' % err)
                      raise self.socket_error
  
                  self.data_send = self.data_send[i:]
                  self.data_sent_bytes = self.data_sent_bytes + i
  
  
              # There is data to read
              gotreq = 0
              if rs:
  
                  # We're the receiving thread, parse the data
                  if receiving:
                      try:
                          count = self.recv_packet_len - len(self.data_recv)
                          count = max(self.recv_buffer_size, count)
                          bytes_recv = self.socket.recv(count)
                      except socket.error as err:
                          self.close_internal('server: %s' % err)
                          raise self.socket_error
  
                      if not bytes_recv:
                          # Clear up, set a connection closed indicator and raise it
                          self.close_internal('server')
                          raise self.socket_error
  
                      self.data_recv = bytes(self.data_recv) + bytes_recv
                      gotreq = self.parse_response(request)
  
                  # Otherwise return, allowing the calling thread to figure
                  # out if it has got the data it needs
                  else:
                      # We must be a sending thread if we're here, so reset
                      # that indicator.
                      self.send_recv_lock.acquire()
                      self.send_active = 0
                      self.send_recv_lock.release()
  
                      # And return to the caller
                      return
  
  
              # There are three different end of send-recv-loop conditions.
              # However, we don't leave the loop immediately, instead we
              # try to send and receive any data that might be left.  We
              # do this by giving a timeout of 0 to select to poll
              # the socket.
  
              # When flushing: all requests have been sent
              if flush and flush_bytes >= self.data_sent_bytes:
                  break
  
              # When waiting for an event: an event has been read
              if event and self.event_queue:
                  break
  
              # When processing a certain request: got its reply
              if request is not None and gotreq:
                  break
  
              # Always break if we just want to receive as much as possible
              if recv:
                  break
  
              # Else there's may still data which must be sent, or
              # we haven't got the data we waited for.  Lock and loop
  
              self.send_recv_lock.acquire()
  
  
          # We have accomplished the callers request.
          # Record that there are now no active send_and_recv,
          # and wake up all waiting thread
  
          self.send_recv_lock.acquire()
  
          if sending:
              self.send_active = 0
          if receiving:
              self.recv_active = 0
  
          if self.event_waiting:
              self.event_waiting = 0
              self.event_wait_lock.release()
  
          if self.request_waiting:
              self.request_waiting = 0
              self.request_wait_lock.release()
  
          self.send_recv_lock.release()
  
  
      def parse_response(self, request):
          """Internal method.
  
          Parse data received from server.  If REQUEST is not None
          true is returned if the request with that serial number
          was received, otherwise false is returned.
  
          If REQUEST is -1, we're parsing the server connection setup
          response.
          """
  
          if request == -1:
              return self.parse_connection_setup()
  
          # Parse ordinary server response
          gotreq = 0
          while 1:
              if self.data_recv:
                  # Check the first byte to find out what kind of response it is
                  rtype = byte2int(self.data_recv)
  
              # Are we're waiting for additional data for the current packet?
              if self.recv_packet_len:
                  if len(self.data_recv) < self.recv_packet_len:
                      return gotreq
  
                  if rtype == 1:
                      gotreq = self.parse_request_response(request) or gotreq
                      continue
                  elif rtype & 0x7f == ge.GenericEventCode:
                      self.parse_event_response(rtype)
                      continue
                  else:
                      raise AssertionError(rtype)
  
              # Every response is at least 32 bytes long, so don't bother
              # until we have received that much
              if len(self.data_recv) < 32:
                  return gotreq
  
              # Error response
              if rtype == 0:
                  gotreq = self.parse_error_response(request) or gotreq
  
              # Request response or generic event.
              elif rtype == 1 or rtype & 0x7f == ge.GenericEventCode:
                  # Set reply length, and loop around to see if
                  # we have got the full response
                  rlen = int(struct.unpack('=L', self.data_recv[4:8])[0])
                  self.recv_packet_len = 32 + rlen * 4
  
              # Else non-generic event
              else:
                  self.parse_event_response(rtype)
  
  
      def parse_error_response(self, request):
          # Code is second byte
          code = indexbytes(self.data_recv, 1)
  
          # Fetch error class
          estruct = self.error_classes.get(code, error.XError)
  
          e = estruct(self, self.data_recv[:32])
          self.data_recv = bytesview(self.data_recv, 32)
  
          # print 'recv Error:', e
  
          req = self.get_waiting_request(e.sequence_number)
  
          # Error for a request whose response we are waiting for,
          # or which have an error handler.  However, if the error
          # handler indicates that it hasn't taken care of the
          # error, pass it on to the default error handler
  
          if req and req._set_error(e):
  
              # If this was a ReplyRequest, unlock any threads waiting
              # for a request to finish
  
              if isinstance(req, rq.ReplyRequest):
                  self.send_recv_lock.acquire()
  
                  if self.request_waiting:
                      self.request_waiting = 0
                      self.request_wait_lock.release()
  
                  self.send_recv_lock.release()
  
              return request == e.sequence_number
  
          # Else call the error handler
          else:
              if self.error_handler:
                  rq.call_error_handler(self.error_handler, e, None)
              else:
                  self.default_error_handler(e)
  
              return 0
  
  
      def default_error_handler(self, err):
          sys.stderr.write('X protocol error:\n%s\n' % err)
  
  
      def parse_request_response(self, request):
          req = self.get_waiting_replyrequest()
  
          # Sequence number is always data[2:4]
          # Do sanity check before trying to parse the data
          sno = struct.unpack('=H', self.data_recv[2:4])[0]
          if sno != req._serial:
              raise RuntimeError("Expected reply for request %s, but got %s.  Can't happen!"
                                 % (req._serial, sno))
  
          req._parse_response(self.data_recv[:self.recv_packet_len])
          # print 'recv Request:', req
  
          self.data_recv = bytesview(self.data_recv, self.recv_packet_len)
          self.recv_packet_len = 0
  
  
          # Unlock any response waiting threads
  
          self.send_recv_lock.acquire()
  
          if self.request_waiting:
              self.request_waiting = 0
              self.request_wait_lock.release()
  
          self.send_recv_lock.release()
  
  
          return req.sequence_number == request
  
  
      def parse_event_response(self, etype):
          # Skip bit 8, that is set if this event came from an SendEvent
          etype = etype & 0x7f
  
          if etype == ge.GenericEventCode:
              length = self.recv_packet_len
          else:
              length = 32
  
          estruct = self.event_classes.get(etype, event.AnyEvent)
          if type(estruct) == dict:
              subcode = self.data_recv[1]
  
              # Python2 compatibility
              if type(subcode) == str:
                  subcode = ord(subcode)
  
              # this etype refers to a set of sub-events with individual subcodes
              estruct = estruct[subcode]
  
          e = estruct(display = self, binarydata = self.data_recv[:length])
  
          if etype == ge.GenericEventCode:
              self.recv_packet_len = 0
  
          self.data_recv = bytesview(self.data_recv, length)
  
          # Drop all requests having an error handler,
          # but which obviously succeded.
  
          # Decrement it by one, so that we don't remove the request
          # that generated these events, if there is such a one.
          # Bug reported by Ilpo Nyyssönen
          # Note: not all events have a sequence_number field!
          # (e.g. KeymapNotify).
          if hasattr(e, 'sequence_number'):
              self.get_waiting_request((e.sequence_number - 1) % 65536)
  
          # print 'recv Event:', e
  
          # Insert the event into the queue
          self.event_queue_write_lock.acquire()
          self.event_queue.append(e)
          self.event_queue_write_lock.release()
  
          # Unlock any event waiting threads
          self.send_recv_lock.acquire()
  
          if self.event_waiting:
              self.event_waiting = 0
              self.event_wait_lock.release()
  
          self.send_recv_lock.release()
  
  
      def get_waiting_request(self, sno):
          if not self.sent_requests:
              return None
  
          # Normalize sequence numbers, even if they have wrapped.
          # This ensures that
          #   sno <= last_serial
          # and
          #   self.sent_requests[0]._serial <= last_serial
  
          if self.sent_requests[0]._serial > self.request_serial:
              last_serial = self.request_serial + 65536
              if sno < self.request_serial:
                  sno = sno + 65536
  
          else:
              last_serial = self.request_serial
              if sno > self.request_serial:
                  sno = sno - 65536
  
          # No matching events at all
          if sno < self.sent_requests[0]._serial:
              return None
  
          # Find last req <= sno
          req = None
          reqpos = len(self.sent_requests)
          adj = 0
          last = 0
  
          for i in range(0, len(self.sent_requests)):
              rno = self.sent_requests[i]._serial + adj
  
              # Did serial numbers just wrap around?
              if rno < last:
                  adj = 65536
                  rno = rno + adj
  
              last = rno
  
              if sno == rno:
                  req = self.sent_requests[i]
                  reqpos = i + 1
                  break
              elif sno < rno:
                  req = None
                  reqpos = i
                  break
  
          # Delete all request such as req <= sno
          del self.sent_requests[:reqpos]
  
          return req
  
      def get_waiting_replyrequest(self):
          for i in range(0, len(self.sent_requests)):
              if hasattr(self.sent_requests[i], '_reply'):
                  req = self.sent_requests[i]
                  del self.sent_requests[:i + 1]
                  return req
  
          # Reply for an unknown request?  No, that can't happen.
          else:
              raise RuntimeError("Request reply to unknown request.  Can't happen!")
  
      def parse_connection_setup(self):
          """Internal function used to parse connection setup response.
          """
  
          # Only the ConnectionSetupRequest has been sent so far
          r = self.sent_requests[0]
  
          while 1:
              # print 'data_send:', repr(self.data_send)
              # print 'data_recv:', repr(self.data_recv)
  
              if r._data:
                  alen = r._data['additional_length'] * 4
  
                  # The full response haven't arrived yet
                  if len(self.data_recv) < alen:
                      return 0
  
                  # Connection failed or further authentication is needed.
                  # Set reason to the reason string
                  if r._data['status'] != 1:
                      r._data['reason'] = self.data_recv[:r._data['reason_length']]
  
                  # Else connection succeeded, parse the reply
                  else:
                      x, d = r._success_reply.parse_binary(self.data_recv[:alen],
                                                           self, rawdict = 1)
                      r._data.update(x)
  
                  del self.sent_requests[0]
  
                  self.data_recv = self.data_recv[alen:]
  
                  return 1
  
              else:
                  # The base reply is 8 bytes long
                  if len(self.data_recv) < 8:
                      return 0
  
                  r._data, d = r._reply.parse_binary(self.data_recv[:8],
                                                     self, rawdict = 1)
                  self.data_recv = self.data_recv[8:]
  
                  # Loop around to see if we have got the additional data
                  # already
  
  
  PixmapFormat = rq.Struct( rq.Card8('depth'),
                            rq.Card8('bits_per_pixel'),
                            rq.Card8('scanline_pad'),
                            rq.Pad(5)
                            )
  
  VisualType = rq.Struct ( rq.Card32('visual_id'),
                           rq.Card8('visual_class'),
                           rq.Card8('bits_per_rgb_value'),
                           rq.Card16('colormap_entries'),
                           rq.Card32('red_mask'),
                           rq.Card32('green_mask'),
                           rq.Card32('blue_mask'),
                           rq.Pad(4)
                           )
  
  Depth = rq.Struct( rq.Card8('depth'),
                     rq.Pad(1),
                     rq.LengthOf('visuals', 2),
                     rq.Pad(4),
                     rq.List('visuals', VisualType)
                     )
  
  Screen = rq.Struct( rq.Window('root'),
                      rq.Colormap('default_colormap'),
                      rq.Card32('white_pixel'),
                      rq.Card32('black_pixel'),
                      rq.Card32('current_input_mask'),
                      rq.Card16('width_in_pixels'),
                      rq.Card16('height_in_pixels'),
                      rq.Card16('width_in_mms'),
                      rq.Card16('height_in_mms'),
                      rq.Card16('min_installed_maps'),
                      rq.Card16('max_installed_maps'),
                      rq.Card32('root_visual'),
                      rq.Card8('backing_store'),
                      rq.Card8('save_unders'),
                      rq.Card8('root_depth'),
                      rq.LengthOf('allowed_depths', 1),
                      rq.List('allowed_depths', Depth)
                      )
  
  
  class ConnectionSetupRequest(rq.GetAttrData):
      _request = rq.Struct( rq.Set('byte_order', 1, (0x42, 0x6c)),
                            rq.Pad(1),
                            rq.Card16('protocol_major'),
                            rq.Card16('protocol_minor'),
                            rq.LengthOf('auth_prot_name', 2),
                            rq.LengthOf('auth_prot_data', 2),
                            rq.Pad(2),
                            rq.String8('auth_prot_name'),
                            rq.String8('auth_prot_data') )
  
      _reply = rq.Struct ( rq.Card8('status'),
                           rq.Card8('reason_length'),
                           rq.Card16('protocol_major'),
                           rq.Card16('protocol_minor'),
                           rq.Card16('additional_length') )
  
      _success_reply = rq.Struct( rq.Card32('release_number'),
                                  rq.Card32('resource_id_base'),
                                  rq.Card32('resource_id_mask'),
                                  rq.Card32('motion_buffer_size'),
                                  rq.LengthOf('vendor', 2),
                                  rq.Card16('max_request_length'),
                                  rq.LengthOf('roots', 1),
                                  rq.LengthOf('pixmap_formats', 1),
                                  rq.Card8('image_byte_order'),
                                  rq.Card8('bitmap_format_bit_order'),
                                  rq.Card8('bitmap_format_scanline_unit'),
                                  rq.Card8('bitmap_format_scanline_pad'),
                                  rq.Card8('min_keycode'),
                                  rq.Card8('max_keycode'),
                                  rq.Pad(4),
                                  rq.String8('vendor'),
                                  rq.List('pixmap_formats', PixmapFormat),
                                  rq.List('roots', Screen),
                                  )
  
  
      def __init__(self, display, *args, **keys):
          self._binary = self._request.to_binary(*args, **keys)
          self._data = None
  
          # Don't bother about locking, since no other threads have
          # access to the display yet
  
          display.request_queue.append((self, 1))
  
          # However, we must lock send_and_recv, but we don't have
          # to loop.
  
          display.send_recv_lock.acquire()
          display.send_and_recv(request = -1)
  