#
# Copyright (c) 2005
#      The President and Fellows of Harvard College.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 3. Neither the name of the University nor the names of its contributors
#    may be used to endorse or promote products derived from this software
#    without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# Author: Geoffrey Mainland <mainland@eecs.harvard.edu>
#
import socket

from IO import *

class SocketIO(IO):
    def __init__(self, host, port):
        IO.__init__(self)

        self.done = False

        self.host = host
        self.port = port

        self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        self.socket.setsockopt(socket.IPPROTO_TCP,
                               socket.TCP_NODELAY,
                               1)
        self.socket.settimeout(1)
        self.socket.bind(("", 0))

    def cancel(self):
        self.done = True

    def open(self):
        print "SocketIO: Connecting socket to "+str(self.host)+":"+str(self.port)
        self.socket.connect((self.host, self.port))
        self.socket.settimeout(1)

    def close(self):
        if self.socket is not None:
            self.socket.close()
            self.socket = None

    def read(self, count):
        data = ""
        while count - len(data) > 0:
            if self.isDone():
                raise IODone()

            try:
                p = self.socket.recv(count - len(data))
                if len(p) == 0:
                    raise IODone() # the remote side closed the connection
                data += p
            except socket.timeout:
                pass

        return data

    def write(self, data):
        return self.socket.send(data)

    def flush(self):
        pass
