#

# Analogue of `multiprocessing.connection` which uses queues instead of sockets

#

# multiprocessing/dummy/connection.py

#

# Copyright (c) 2006-2008, R Oudkerk --- see COPYING.txt

#

__all__ = [ 'Client', 'Listener', 'Pipe' ]

from Queue import Queue

families = [None]

class Listener(object):

    def __init__(self, address=None, family=None, backlog=1):

        self._backlog_queue = Queue(backlog)

    def accept(self):

        return Connection(*self._backlog_queue.get())

    def close(self):

        self._backlog_queue = None

    address = property(lambda self: self._backlog_queue)

def Client(address):

    _in, _out = Queue(), Queue()

    address.put((_out, _in))

    return Connection(_in, _out)

def Pipe(duplex=True):

    a, b = Queue(), Queue()

    return Connection(a, b), Connection(b, a)

class Connection(object):

    def __init__(self, _in, _out):

        self._out = _out

        self._in = _in

        self.send = self.send_bytes = _out.put

        self.recv = self.recv_bytes = _in.get

    def poll(self, timeout=0.0):

        if self._in.qsize() > 0:

            return True

        if timeout <= 0.0:

            return False

        self._in.not_empty.acquire()

        self._in.not_empty.wait(timeout)

        self._in.not_empty.release()

        return self._in.qsize() > 0

    def close(self):

        pass