Viewing file:  TarIO.py (1.7 KB) -rw-r--r--
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#
# 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.
#
from __future__ import annotations
import io
from types import TracebackType
from . import ContainerIO
class TarIO(ContainerIO.ContainerIO[bytes]):
"""A file object that provides read access to a given member of a TAR file."""
def __init__(self, tarfile: str, file: str) -> None:
"""
Create file object.
:param tarfile: Name of TAR file.
:param file: Name of member file.
"""
self.fh = open(tarfile, "rb")
while True:
s = self.fh.read(512)
if len(s) != 512:
msg = "unexpected end of tar file"
raise OSError(msg)
name = s[:100].decode("utf-8")
i = name.find("\0")
if i == 0:
msg = "cannot find subfile"
raise OSError(msg)
if i > 0:
name = name[:i]
size = int(s[124:135], 8)
if file == name:
break
self.fh.seek((size + 511) & (~511), io.SEEK_CUR)
# Open region
super().__init__(self.fh, self.fh.tell(), size)
# Context manager support
def __enter__(self) -> TarIO:
return self
def __exit__(
self,
exc_type: type[BaseException] | None,
exc_val: BaseException | None,
exc_tb: TracebackType | None,
) -> None:
self.close()
def close(self) -> None:
self.fh.close()
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