#!/usr/bin/python
# A generic proxy server
# usage: proxy.py listenport targethost targetport
# Example: proxy.py 7777 www.cnn.com 80

import select, socket, SocketServer, string, sys

listenport= string.atoi(sys.argv[1])
targethost= sys.argv[2]
targetport= string.atoi(sys.argv[3])

class Handler(SocketServer.BaseRequestHandler):
    def fromclient_callback(self, text, target_socket):
        #print "From client"  #print text
        target_socket.send(text)  # pass it along
        
    def fromserver_callback(self, text, client_socket):
        #print "From server"  #print text
        client_socket.send(text)  # pass it along
        
    def handle(self):
        # Override of SocketServer.BaseRequestHandler.handle()
        #print "Handle..."
	self.request.setblocking(0)
        target_socket= socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        target_socket.connect((targethost, targetport))
        closing= 0
        select_list= [self.request, target_socket]
        while 1:  # Keep looping until one of the connections gets closed from other end
            ready_to_read, ready_to_write, in_error =  select.select(
                          select_list, [], select_list, 
                          15000)
            for s in ready_to_read:
                if s== self.request:
		    try:
                        fromclient= self.request.recv(999999)
                        self.fromclient_callback(fromclient, target_socket)
                    except socket.error, msg:
                        in_error.append(s)  # so we'll process as error below
                if s== target_socket:
		    try:
                        fromserver= target_socket.recv(999999)
                        self.fromserver_callback(fromserver, self.request)
                    except socket.error, msg:
                        in_error.append(s)  # so we'll process as error below
            for s in in_error:
                #print "Closing..."
                s.close()
            if len(in_error)> 0:
                #print "...Handle"
                return

server= SocketServer.TCPServer(('127.0.0.1',listenport), Handler)
server.serve_forever()