dcc.py

# -*- encoding: utf-8 -*-
"""
   This program 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 of the License, or
   (at your option) any later version.

   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
"""

from threading import Thread
import socket


# For sending 4 byte's throught a socket
def int2uint4( n ):
    u = ""
    for i in range( 0, 4 ):
            u = chr(n % 256) + u
            n /= 256
    return u

########################################################################
# DCC download thread
class dcc_download( Thread ):
    
    ####################################################################
    # Constructor
    def __init__( self, 
                  msg,
                  func = None,
                  buffsize = 1024 ):

        Thread.__init__( self )
                      
        self.buffsize = buffsize
        self.turbo = msg.turbo
        self.ip = msg.ip
        self.port = msg.port
        self.f = open( msg.file, "wb" )
        self.func = func
        self.size = msg.size



    ####################################################################
    # Here starts the thread
    def run(self):
        
        sock = socket.socket( socket.AF_INET, socket.SOCK_STREAM )
        
        sock.connect(( self.ip, self.port ))
        r_size = 0
        
        while ( r_size < self.size ) or  ( self.size == -1 ):
            c = sock.recv( self.buffsize )
            if ( not self.turbo ):
                try:
                    r_size += len(c)
                    sock.send(int2uint4(len(c)))
                except:
                    break
                    
            if ( len( c ) < 1 ):
                break
                
            self.f.write( c )
            
        if ( r_size >= self.size ):
            sock.send(int2uint4( 0 ))
            
        self.f.close( )
        sock.close( )
        
        if ( self.func != None ):
            self.func( )


########################################################################
# Cleans the message
def clean_msg( s ):
    for c in range( 1, 10 ):
        s = s.replace( ord( c ) ,'' )
    return s

########################################################################
# Converts a port number to a string
def ntop( i ):
    ip = ""
    ip += str(( i / 16777216 ) % 256 ) + "."
    ip += str(( i / 65536) %256 ) + "."
    ip += str(( i / 256) % 256 ) + "."
    ip += str( i % 256 )
    return ip

########################################################################
# Get DCC offer
def decompose_dcc_offer( m ):

    if ( "DCC SEND" in m ):
        l = m.index( "DCC SEND" )
        turbo = False

    else:

        if ( "DCC TSEND" in m ):
            l = m.index("DCC TSEND")
            turbo = True

        else:
            return False

    if ( " " in m ):
        aux = m[ m.index( " ", l + 4 ) : ]
        
        if ( len( aux ) < 1 ):
            return False

        while ( aux[ 0 ] == " " ):
            aux = aux[1:]
            if ( len( aux ) < 1 ):
                return False


        if ( aux [ 0 ] == '"'):
            
            if ( '"' in aux[ 1 : ] ):
            
                fname = aux[ 1 : aux.index( '"', 1 ) ]

                aux = aux[ aux.index( '"', 1 ) + 1 : ]
                
            else:
                return False

        elif ( aux[ 0 ] == "'" ):
            if ( "'" in aux[ 1 : ] ):
                fname = aux[ 1 : aux.index( "'", 1 ) ]
                aux = aux[ aux.index( "'", 1 ) + 1 : ]
        elif ( ' ' in aux ) :
            fname = aux[ : aux.index( " " )]
            aux = aux[aux.index( " " ) + 1 : ]

        else:
            return False

    # To avoid path's in the filename
        fname = fname.split( "/" )[ -1 ]
        fname = fname.split( "\\" )[ -1 ]

        if ( len( aux ) < 1 ):
            return False
            
        while ( aux[ 0 ] == " " ):
            aux = aux[ 1: ]

        if ( len( aux ) > 1 ) and ( " " in aux ):

            ip = int( aux[ : aux.index( " " ) ])

            aux = aux[ aux.index( " " ) + 1 : ]
            port = int( aux[ : aux.index( " " ) ])

            ip = ntop( ip )

            if ( " " in aux ):
                aux = aux[ aux.index( " " ) + 1 : ]
                size = int( aux )
                
                return ( ip, port, fname, turbo, size )

            if ( ip != "" ):
                return ( ip, port, fname, turbo, -1 )

        else:
            return False

    return False