#!/usr/bin/env python
#
# Create veth pairs and start up switch daemons
#

import os
from subprocess import Popen,PIPE,call,check_call
from optparse import OptionParser

parser = OptionParser(version="%prog 0.1")
parser.set_defaults(port_count=4)
parser.set_defaults(of_dir="../../openflow")
parser.set_defaults(port=6633)
parser.add_option("-n", "--port_count", type="int",
                  help="Number of veth pairs to create")
parser.add_option("-o", "--of_dir", help="OpenFlow root directory for host")
parser.add_option("-p", "--port", type="int",
                  help="Port for OFP to listen on")
(options, args) = parser.parse_args()

call(["/sbin/modprobe", "veth"])
for idx in range(0, options.port_count):
    print "Creating veth pair " + str(idx)
    call(["/sbin/ip", "link", "add", "type", "veth"])

for idx in range(0, 2 * options.port_count):
    cmd = ["/sbin/ifconfig", 
           "veth" + str(idx), 
           "192.168.1" + str(idx) + ".1", 
           "netmask", 
           "255.255.255.0"]
    print "Cmd: " + str(cmd)
    call(cmd)

veths = "veth0"
for idx in range(1, options.port_count):
    veths += ",veth" + str(2 * idx)

ofd = options.of_dir + "/udatapath/ofdatapath"
ofp = options.of_dir + "/secchan/ofprotocol"

try:
    check_call(["ls", ofd])
except:
    print "Could not find datapath daemon: " + ofd
    os.exit(1)

try:
    check_call(["ls", ofp])
except:
    print "Could not find protocol daemon: " + ofp
    os.exit(1)

ofd_op = Popen([ofd, "-i", veths, "punix:/tmp/ofd"])
print "Started ofdatapath on IFs " + veths + " with pid " + str(ofd_op.pid)

print "Starting ofprotocol; ^C to quit"
call([ofp, "unix:/tmp/ofd", "tcp:127.0.0.1:" + str(options.port),
      "--fail=closed", "--max-backoff=1"])

ofd_op.kill()