pyscard issue

#! /usr/bin/env python
"""
Sample for python PCSC wrapper module: Detect card insertion/removal

__author__ = "http://www.gemalto.com"

Copyright 2001-2012 gemalto
Author: Jean-Daniel Aussel, mailto:jean-daniel.aussel@gemalto.com
Copyright 2010 Ludovic Rousseau
Author: Ludovic Rousseau, mailto:ludovic.rousseau@free.fr

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.scard import *
import smartcard.util

srTreeATR = \
    [0x3B, 0x77, 0x94, 0x00, 0x00, 0x82, 0x30, 0x00, 0x13, 0x6C, 0x9F, 0x22]
srTreeMask = \
    [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]


def printstate(state):
    reader, eventstate, atr = state
    print reader + " " + smartcard.util.toHexString(atr, smartcard.util.HEX)
    if eventstate & SCARD_STATE_ATRMATCH:
        print '\tCard found'
    if eventstate & SCARD_STATE_UNAWARE:
        print '\tState unware'
    if eventstate & SCARD_STATE_IGNORE:
        print '\tIgnore reader'
    if eventstate & SCARD_STATE_UNAVAILABLE:
        print '\tReader unavailable'
    if eventstate & SCARD_STATE_EMPTY:
        print '\tReader empty'
    if eventstate & SCARD_STATE_PRESENT:
        print '\tCard present in reader'
    if eventstate & SCARD_STATE_EXCLUSIVE:
        print '\tCard allocated for exclusive use by another application'
    if eventstate & SCARD_STATE_INUSE:
        print '\tCard in used by another application but can be shared'
    if eventstate & SCARD_STATE_MUTE:
        print '\tCard is mute'
    if eventstate & SCARD_STATE_CHANGED:
        print '\tState changed'
    if eventstate & SCARD_STATE_UNKNOWN:
        print '\tState unknowned'


try:
    hresult, hcontext = SCardEstablishContext(SCARD_SCOPE_USER)
    if hresult != SCARD_S_SUCCESS:
        raise error(
            'Failed to establish context: ' + \
            SCardGetErrorMessage(hresult))
    print 'Context established!'

    try:
        hresult, readers = SCardListReaders(hcontext, [])
        if hresult != SCARD_S_SUCCESS:
            raise error(
                'Failed to list readers: ' + \
                SCardGetErrorMessage(hresult))
        print 'PCSC Readers:', readers


        while True:
            readerstates = []
            for i in xrange(len(readers)):
                readerstates += [(readers[i], SCARD_STATE_UNAWARE)]

            print '----- Current reader and card states are: -------'
            hresult, newstates = SCardGetStatusChange(hcontext, 0, readerstates)
            for i in newstates:
                printstate(i)
            print '----- Please insert or remove a card ------------'
            hresult, newstates = SCardGetStatusChange(
                                    hcontext,
                                    INFINITE,
                                    newstates)

            print '----- New reader and card states are: -----------'
            for i in newstates:
                printstate(i)

    finally:
        hresult = SCardReleaseContext(hcontext)
        if hresult != SCARD_S_SUCCESS:
            raise error(
                'Failed to release context: ' + \
                SCardGetErrorMessage(hresult))
        print 'Released context.'

    import sys
    if 'win32' == sys.platform:
        print 'press Enter to continue'
        sys.stdin.read(1)

except error, e:
    print e