#
# Copyright 2009 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# GNU Radio is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3, or (at your option)
# any later version.
#
# GNU Radio 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with GNU Radio; see the file COPYING.  If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
#

from gnuradio import gr
import socket
import os

def _get_sock_fd(addr, port, server):
	"""
	Get the file descriptor for the socket.
	As a client, block on connect, dup the socket descriptor.
	As a server, block on accept, dup the client descriptor.
	@param addr the ip address string
	@param port the tcp port number
	@param server true for server mode, false for client mode
	@return the file descriptor number
	"""
	sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
	if server:
		sock.bind((addr, port))
		sock.listen(1)
		clientsock, address = sock.accept()
		return os.dup(clientsock.fileno())
	else:
		sock.connect((addr, port))
		return os.dup(sock.fileno())

class tcp_source(gr.hier_block2):
	def __init__(self, itemsize, addr, port, server=True):
		#init hier block
		gr.hier_block2.__init__(
			self, 'tcp_source',
			gr.io_signature(0, 0, 0),
			gr.io_signature(1, 1, itemsize),
		)
		fd = _get_sock_fd(addr, port, server)
		self.connect(gr.file_descriptor_source(itemsize, fd), self)

class tcp_sink(gr.hier_block2):
	def __init__(self, itemsize, addr, port, server=False):
		#init hier block
		gr.hier_block2.__init__(
			self, 'tcp_sink',
			gr.io_signature(1, 1, itemsize),
			gr.io_signature(0, 0, 0),
		)
		fd = _get_sock_fd(addr, port, server)
		self.connect(self, gr.file_descriptor_sink(itemsize, fd))