multicast

[Seb]

Forgot the code... doh! :)

#! /usr/bin/env python

import socket
import time

class MulticastSender(object):
	def __init__(self, MCAST_ADDR = "224.168.2.9", MCAST_PORT = 1600):
		self.MCAST_ADDR = MCAST_ADDR
		self.MCAST_PORT = MCAST_PORT
		ANY = "0.0.0.0"
		SENDERPORT=1501
#create a UDP socket
		self.sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM,
socket.IPPROTO_UDP)
#allow multiple sockets to use the same PORT number
		self.sock.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
#The sender is bound on (0.0.0.0:1501)
		self.sock.bind((ANY,SENDERPORT))
#Tell the kernel that we want to multicast and that the data is sent
#to everyone (255 is the level of multicasting)
		self.sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL,
255)

	def send(self, data):
		self.sock.sendto(data, (self.MCAST_ADDR, self.MCAST_PORT));

class MulticastReceiver(object):
	def __init__(self, MCAST_ADDR = "224.168.2.9", MCAST_PORT = 1600):
		ANY = "0.0.0.0"
#create a UDP socket
		self.sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM,
socket.IPPROTO_UDP)
#allow multiple sockets to use the same PORT number
		self.sock.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
#Bind to the port that we know will receive multicast data
		self.sock.bind((ANY,MCAST_PORT))
#tell the kernel that we are a multicast socket
		self.sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL,
255)
#Tell the kernel that we want to add ourselves to a multicast group
#The address for the multicast group is the third param
		status = self.sock.setsockopt(socket.IPPROTO_IP,
socket.IP_ADD_MEMBERSHIP, socket.inet_aton(MCAST_ADDR) +
socket.inet_aton(ANY));
		self.sock.setblocking(0)

	def setblocking(self, flag):
		self.sock.setblocking(flag)

	def recv(self, size = 1024):
		return self.sock.recvfrom(size)

class Multicast(object):
	def __init__(self):
		self.__ms = MulticastSender()
		self.__mr = MulticastReceiver()

	def send(self, data):
		self.__ms.send(data)

	def recv(self, size = 1024):
		return self.__mr.recv()

if __name__ == "__main__":
	mc = Multicast()
	while 1:
		try:
			data, addr = mc.recv()
		except socket.error, e:
			#print "sock.error: ", e
			pass
		else:
			print "FROM: ", addr
			print "DATA: ", data