"""Sample CardConnectionDecorator that provides exclusive transmit()
__author__ = "http://www.gemalto.com"
Copyright 2001-2010 gemalto
Author: Jean-Daniel Aussel, mailto:jean-daniel.aussel@gemalto.com
This file is part of pyscard.
pyscard is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
pyscard 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 Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with pyscard; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
"""
from smartcard.CardConnection import CardConnection
from smartcard.CardConnectionDecorator import CardConnectionDecorator
from smartcard.Exceptions import CardConnectionException
from smartcard.scard import SCardBeginTransaction,SCardEndTransaction,SCARD_LEAVE_CARD
from smartcard.scard import SCardGetErrorMessage
from smartcard.pcsc import PCSCCardConnection
import smartcard.pcsc
class ExclusiveTransmitCardConnection( CardConnectionDecorator ):
'''This decorator uses SCardBeginTransaction/SCardEndTransaction
to preserve other processes of threads to access the card during transmit().'''
def __init__( self, cardconnection ):
CardConnectionDecorator.__init__( self, cardconnection )
def lock( self ):
'''Lock card with SCardBeginTransaction.'''
component=self.component
while True:
if isinstance( component, smartcard.pcsc.PCSCCardConnection.PCSCCardConnection ):
hresult = SCardBeginTransaction( component.hcard )
if 0!=hresult:
raise CardConnectionException( 'Failed to lock with SCardBeginTransaction' + SCardGetErrorMessage(hresult) )
else:
#print 'locked'
pass
break
if hasattr( component, 'component' ):
component=component.component
else:
break
def unlock( self ):
'''Unlock card with SCardEndTransaction.'''
component=self.component
while True:
if isinstance( component, smartcard.pcsc.PCSCCardConnection.PCSCCardConnection ):
hresult = SCardEndTransaction( component.hcard, SCARD_LEAVE_CARD )
if 0!=hresult:
raise CardConnectionException( 'Failed to unlock with SCardEndTransaction' + SCardGetErrorMessage(hresult) )
else:
#print 'unlocked'
pass
break
if hasattr( component, 'component' ):
component=component.component
else:
break
def transmit( self, bytes, protocol=None ):
'''Gain exclusive access to card during APDU transmission for if this
decorator decorates a PCSCCardConnection.'''
data, sw1, sw2 = CardConnectionDecorator.transmit( self, bytes, protocol )
return data, sw1, sw2
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