Pillow/PIL/TarIO.py
2010-07-30 22:52:47 -04:00

58 lines
1.2 KiB
Python

#
# The Python Imaging Library.
# $Id$
#
# read files from within a tar file
#
# History:
# 95-06-18 fl Created
# 96-05-28 fl Open files in binary mode
#
# Copyright (c) Secret Labs AB 1997.
# Copyright (c) Fredrik Lundh 1995-96.
#
# See the README file for information on usage and redistribution.
#
import ContainerIO
import string
##
# A file object that provides read access to a given member of a TAR
# file.
class TarIO(ContainerIO.ContainerIO):
##
# Create file object.
#
# @param tarfile Name of TAR file.
# @param file Name of member file.
def __init__(self, tarfile, file):
fh = open(tarfile, "rb")
while 1:
s = fh.read(512)
if len(s) != 512:
raise IOError, "unexpected end of tar file"
name = s[:100]
i = string.find(name, chr(0))
if i == 0:
raise IOError, "cannot find subfile"
if i > 0:
name = name[:i]
size = string.atoi(s[124:136], 8)
if file == name:
break
fh.seek((size + 511) & (~511), 1)
# Open region
ContainerIO.ContainerIO.__init__(self, fh, fh.tell(), size)