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tarfile.py
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#!/usr/bin/env python3
#-------------------------------------------------------------------
# tarfile.py
#-------------------------------------------------------------------
# Copyright (C) 2002 Lars Gustaebel <lars@gustaebel.de>
# All rights reserved.
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation
# files (the "Software"), to deal in the Software without
# restriction, including without limitation the rights to use,
# copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following
# conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.
#
"""Read from and write to tar format archives.
"""
version="0.9.0"
__author__="Lars Gust\u00e4bel (lars@gustaebel.de)"
__credits__="Gustavo Niemeyer, Niels Gust\u00e4bel, Richard Townsend."
#---------
# Imports
#---------
frombuiltinsimportopenasbltn_open
importsys
importos
importio
importshutil
importstat
importtime
importstruct
importcopy
importre
try:
importpwd
exceptImportError:
pwd=None
try:
importgrp
exceptImportError:
grp=None
# os.symlink on Windows prior to 6.0 raises NotImplementedError
# OSError (winerror=1314) will be raised if the caller does not hold the
# SeCreateSymbolicLinkPrivilege privilege
symlink_exception= (AttributeError, NotImplementedError, OSError)
# from tarfile import *
__all__= ["TarFile", "TarInfo", "is_tarfile", "TarError", "ReadError",
"CompressionError", "StreamError", "ExtractError", "HeaderError",
"ENCODING", "USTAR_FORMAT", "GNU_FORMAT", "PAX_FORMAT",
"DEFAULT_FORMAT", "open","fully_trusted_filter", "data_filter",
"tar_filter", "FilterError", "AbsoluteLinkError",
"OutsideDestinationError", "SpecialFileError", "AbsolutePathError",
"LinkOutsideDestinationError"]
#---------------------------------------------------------
# tar constants
#---------------------------------------------------------
NUL=b"\0"# the null character
BLOCKSIZE=512# length of processing blocks
RECORDSIZE=BLOCKSIZE*20# length of records
GNU_MAGIC=b"ustar \0"# magic gnu tar string
POSIX_MAGIC=b"ustar\x0000"# magic posix tar string
LENGTH_NAME=100# maximum length of a filename
LENGTH_LINK=100# maximum length of a linkname
LENGTH_PREFIX=155# maximum length of the prefix field
REGTYPE=b"0"# regular file
AREGTYPE=b"\0"# regular file
LNKTYPE=b"1"# link (inside tarfile)
SYMTYPE=b"2"# symbolic link
CHRTYPE=b"3"# character special device
BLKTYPE=b"4"# block special device
DIRTYPE=b"5"# directory
FIFOTYPE=b"6"# fifo special device
CONTTYPE=b"7"# contiguous file
GNUTYPE_LONGNAME=b"L"# GNU tar longname
GNUTYPE_LONGLINK=b"K"# GNU tar longlink
GNUTYPE_SPARSE=b"S"# GNU tar sparse file
XHDTYPE=b"x"# POSIX.1-2001 extended header
XGLTYPE=b"g"# POSIX.1-2001 global header
SOLARIS_XHDTYPE=b"X"# Solaris extended header
USTAR_FORMAT=0# POSIX.1-1988 (ustar) format
GNU_FORMAT=1# GNU tar format
PAX_FORMAT=2# POSIX.1-2001 (pax) format
DEFAULT_FORMAT=PAX_FORMAT
#---------------------------------------------------------
# tarfile constants
#---------------------------------------------------------
# File types that tarfile supports:
SUPPORTED_TYPES= (REGTYPE, AREGTYPE, LNKTYPE,
SYMTYPE, DIRTYPE, FIFOTYPE,
CONTTYPE, CHRTYPE, BLKTYPE,
GNUTYPE_LONGNAME, GNUTYPE_LONGLINK,
GNUTYPE_SPARSE)
# File types that will be treated as a regular file.
REGULAR_TYPES= (REGTYPE, AREGTYPE,
CONTTYPE, GNUTYPE_SPARSE)
# File types that are part of the GNU tar format.
GNU_TYPES= (GNUTYPE_LONGNAME, GNUTYPE_LONGLINK,
GNUTYPE_SPARSE)
# Fields from a pax header that override a TarInfo attribute.
PAX_FIELDS= ("path", "linkpath", "size", "mtime",
"uid", "gid", "uname", "gname")
# Fields from a pax header that are affected by hdrcharset.
PAX_NAME_FIELDS= {"path", "linkpath", "uname", "gname"}
# Fields in a pax header that are numbers, all other fields
# are treated as strings.
PAX_NUMBER_FIELDS= {
"atime": float,
"ctime": float,
"mtime": float,
"uid": int,
"gid": int,
"size": int
}
#---------------------------------------------------------
# initialization
#---------------------------------------------------------
ifos.name=="nt":
ENCODING="utf-8"
else:
ENCODING=sys.getfilesystemencoding()
#---------------------------------------------------------
# Some useful functions
#---------------------------------------------------------
defstn(s, length, encoding, errors):
"""Convert a string to a null-terminated bytes object.
"""
ifsisNone:
raiseValueError("metadata cannot contain None")
s=s.encode(encoding, errors)
returns[:length] + (length-len(s)) *NUL
defnts(s, encoding, errors):
"""Convert a null-terminated bytes object to a string.
"""
p=s.find(b"\0")
ifp!=-1:
s=s[:p]
returns.decode(encoding, errors)
defnti(s):
"""Convert a number field to a python number.
"""
# There are two possible encodings for a number field, see
# itn() below.
ifs[0] in (0o200, 0o377):
n=0
foriinrange(len(s) -1):
n<<=8
n+=s[i+1]
ifs[0] ==0o377:
n=-(256** (len(s) -1) -n)
else:
try:
s=nts(s, "ascii", "strict")
n=int(s.strip() or"0", 8)
exceptValueError:
raiseInvalidHeaderError("invalid header")
returnn
defitn(n, digits=8, format=DEFAULT_FORMAT):
"""Convert a python number to a number field.
"""
# POSIX 1003.1-1988 requires numbers to be encoded as a string of
# octal digits followed by a null-byte, this allows values up to
# (8**(digits-1))-1. GNU tar allows storing numbers greater than
# that if necessary. A leading 0o200 or 0o377 byte indicate this
# particular encoding, the following digits-1 bytes are a big-endian
# base-256 representation. This allows values up to (256**(digits-1))-1.
# A 0o200 byte indicates a positive number, a 0o377 byte a negative
# number.
original_n=n
n=int(n)
if0<=n<8** (digits-1):
s=bytes("%0*o"% (digits-1, n), "ascii") +NUL
elifformat==GNU_FORMATand-256** (digits-1) <=n<256** (digits-1):
ifn>=0:
s=bytearray([0o200])
else:
s=bytearray([0o377])
n=256**digits+n
foriinrange(digits-1):
s.insert(1, n&0o377)
n>>=8
else:
raiseValueError("overflow in number field")
returns
defcalc_chksums(buf):
"""Calculate the checksum for a member's header by summing up all
characters except for the chksum field which is treated as if
it was filled with spaces. According to the GNU tar sources,
some tars (Sun and NeXT) calculate chksum with signed char,
which will be different if there are chars in the buffer with
the high bit set. So we calculate two checksums, unsigned and
signed.
"""
unsigned_chksum=256+sum(struct.unpack_from("148B8x356B", buf))
signed_chksum=256+sum(struct.unpack_from("148b8x356b", buf))
returnunsigned_chksum, signed_chksum
defcopyfileobj(src, dst, length=None, exception=OSError, bufsize=None):
"""Copy length bytes from fileobj src to fileobj dst.
If length is None, copy the entire content.
"""
bufsize=bufsizeor16*1024
iflength==0:
return
iflengthisNone:
shutil.copyfileobj(src, dst, bufsize)
return
blocks, remainder=divmod(length, bufsize)
forbinrange(blocks):
buf=src.read(bufsize)
iflen(buf) <bufsize:
raiseexception("unexpected end of data")
dst.write(buf)
ifremainder!=0:
buf=src.read(remainder)
iflen(buf) <remainder:
raiseexception("unexpected end of data")
dst.write(buf)
return
def_safe_print(s):
encoding=getattr(sys.stdout, 'encoding', None)
ifencodingisnotNone:
s=s.encode(encoding, 'backslashreplace').decode(encoding)
print(s, end=' ')
classTarError(Exception):
"""Base exception."""
pass
classExtractError(TarError):
"""General exception for extract errors."""
pass
classReadError(TarError):
"""Exception for unreadable tar archives."""
pass
classCompressionError(TarError):
"""Exception for unavailable compression methods."""
pass
classStreamError(TarError):
"""Exception for unsupported operations on stream-like TarFiles."""
pass
classHeaderError(TarError):
"""Base exception for header errors."""
pass
classEmptyHeaderError(HeaderError):
"""Exception for empty headers."""
pass
classTruncatedHeaderError(HeaderError):
"""Exception for truncated headers."""
pass
classEOFHeaderError(HeaderError):
"""Exception for end of file headers."""
pass
classInvalidHeaderError(HeaderError):
"""Exception for invalid headers."""
pass
classSubsequentHeaderError(HeaderError):
"""Exception for missing and invalid extended headers."""
pass
#---------------------------
# internal stream interface
#---------------------------
class_LowLevelFile:
"""Low-level file object. Supports reading and writing.
It is used instead of a regular file object for streaming
access.
"""
def__init__(self, name, mode):
mode= {
"r": os.O_RDONLY,
"w": os.O_WRONLY|os.O_CREAT|os.O_TRUNC,
}[mode]
ifhasattr(os, "O_BINARY"):
mode|=os.O_BINARY
self.fd=os.open(name, mode, 0o666)
defclose(self):
os.close(self.fd)
defread(self, size):
returnos.read(self.fd, size)
defwrite(self, s):
os.write(self.fd, s)
class_Stream:
"""Class that serves as an adapter between TarFile and
a stream-like object. The stream-like object only
needs to have a read() or write() method that works with bytes,
and the method is accessed blockwise.
Use of gzip or bzip2 compression is possible.
A stream-like object could be for example: sys.stdin.buffer,
sys.stdout.buffer, a socket, a tape device etc.
_Stream is intended to be used only internally.
"""
def__init__(self, name, mode, comptype, fileobj, bufsize,
compresslevel):
"""Construct a _Stream object.
"""
self._extfileobj=True
iffileobjisNone:
fileobj=_LowLevelFile(name, mode)
self._extfileobj=False
ifcomptype=='*':
# Enable transparent compression detection for the
# stream interface
fileobj=_StreamProxy(fileobj)
comptype=fileobj.getcomptype()
self.name=nameor""
self.mode=mode
self.comptype=comptype
self.fileobj=fileobj
self.bufsize=bufsize
self.buf=b""
self.pos=0
self.closed=False
try:
ifcomptype=="gz":
try:
importzlib
exceptImportError:
raiseCompressionError("zlib module is not available") fromNone
self.zlib=zlib
self.crc=zlib.crc32(b"")
ifmode=="r":
self.exception=zlib.error
self._init_read_gz()
else:
self._init_write_gz(compresslevel)
elifcomptype=="bz2":
try:
importbz2
exceptImportError:
raiseCompressionError("bz2 module is not available") fromNone
ifmode=="r":
self.dbuf=b""
self.cmp=bz2.BZ2Decompressor()
self.exception=OSError
else:
self.cmp=bz2.BZ2Compressor(compresslevel)
elifcomptype=="xz":
try:
importlzma
exceptImportError:
raiseCompressionError("lzma module is not available") fromNone
ifmode=="r":
self.dbuf=b""
self.cmp=lzma.LZMADecompressor()
self.exception=lzma.LZMAError
else:
self.cmp=lzma.LZMACompressor()
elifcomptype!="tar":
raiseCompressionError("unknown compression type %r"%comptype)
except:
ifnotself._extfileobj:
self.fileobj.close()
self.closed=True
raise
def__del__(self):
ifhasattr(self, "closed") andnotself.closed:
self.close()
def_init_write_gz(self, compresslevel):
"""Initialize for writing with gzip compression.
"""
self.cmp=self.zlib.compressobj(compresslevel,
self.zlib.DEFLATED,
-self.zlib.MAX_WBITS,
self.zlib.DEF_MEM_LEVEL,
0)
timestamp=struct.pack("<L", int(time.time()))
self.__write(b"\037\213\010\010"+timestamp+b"\002\377")
ifself.name.endswith(".gz"):
self.name=self.name[:-3]
# Honor "directory components removed" from RFC1952
self.name=os.path.basename(self.name)
# RFC1952 says we must use ISO-8859-1 for the FNAME field.
self.__write(self.name.encode("iso-8859-1", "replace") +NUL)
defwrite(self, s):
"""Write string s to the stream.
"""
ifself.comptype=="gz":
self.crc=self.zlib.crc32(s, self.crc)
self.pos+=len(s)
ifself.comptype!="tar":
s=self.cmp.compress(s)
self.__write(s)
def__write(self, s):
"""Write string s to the stream if a whole new block
is ready to be written.
"""
self.buf+=s
whilelen(self.buf) >self.bufsize:
self.fileobj.write(self.buf[:self.bufsize])
self.buf=self.buf[self.bufsize:]
defclose(self):
"""Close the _Stream object. No operation should be
done on it afterwards.
"""
ifself.closed:
return
self.closed=True
try:
ifself.mode=="w"andself.comptype!="tar":
self.buf+=self.cmp.flush()
ifself.mode=="w"andself.buf:
self.fileobj.write(self.buf)
self.buf=b""
ifself.comptype=="gz":
self.fileobj.write(struct.pack("<L", self.crc))
self.fileobj.write(struct.pack("<L", self.pos&0xffffFFFF))
finally:
ifnotself._extfileobj:
self.fileobj.close()
def_init_read_gz(self):
"""Initialize for reading a gzip compressed fileobj.
"""
self.cmp=self.zlib.decompressobj(-self.zlib.MAX_WBITS)
self.dbuf=b""
# taken from gzip.GzipFile with some alterations
ifself.__read(2) !=b"\037\213":
raiseReadError("not a gzip file")
ifself.__read(1) !=b"\010":
raiseCompressionError("unsupported compression method")
flag=ord(self.__read(1))
self.__read(6)
ifflag&4:
xlen=ord(self.__read(1)) +256*ord(self.__read(1))
self.read(xlen)
ifflag&8:
whileTrue:
s=self.__read(1)
ifnotsors==NUL:
break
ifflag&16:
whileTrue:
s=self.__read(1)
ifnotsors==NUL:
break
ifflag&2:
self.__read(2)
deftell(self):
"""Return the stream's file pointer position.
"""
returnself.pos
defseek(self, pos=0):
"""Set the stream's file pointer to pos. Negative seeking
is forbidden.
"""
ifpos-self.pos>=0:
blocks, remainder=divmod(pos-self.pos, self.bufsize)
foriinrange(blocks):
self.read(self.bufsize)
self.read(remainder)
else:
raiseStreamError("seeking backwards is not allowed")
returnself.pos
defread(self, size):
"""Return the next size number of bytes from the stream."""
assertsizeisnotNone
buf=self._read(size)
self.pos+=len(buf)
returnbuf
def_read(self, size):
"""Return size bytes from the stream.
"""
ifself.comptype=="tar":
returnself.__read(size)
c=len(self.dbuf)
t= [self.dbuf]
whilec<size:
# Skip underlying buffer to avoid unaligned double buffering.
ifself.buf:
buf=self.buf
self.buf=b""
else:
buf=self.fileobj.read(self.bufsize)
ifnotbuf:
break
try:
buf=self.cmp.decompress(buf)
exceptself.exceptionase:
raiseReadError("invalid compressed data") frome
t.append(buf)
c+=len(buf)
t=b"".join(t)
self.dbuf=t[size:]
returnt[:size]
def__read(self, size):
"""Return size bytes from stream. If internal buffer is empty,
read another block from the stream.
"""
c=len(self.buf)
t= [self.buf]
whilec<size:
buf=self.fileobj.read(self.bufsize)
ifnotbuf:
break
t.append(buf)
c+=len(buf)
t=b"".join(t)
self.buf=t[size:]
returnt[:size]
# class _Stream
class_StreamProxy(object):
"""Small proxy class that enables transparent compression
detection for the Stream interface (mode 'r|*').
"""
def__init__(self, fileobj):
self.fileobj=fileobj
self.buf=self.fileobj.read(BLOCKSIZE)
defread(self, size):
self.read=self.fileobj.read
returnself.buf
defgetcomptype(self):
ifself.buf.startswith(b"\x1f\x8b\x08"):
return"gz"
elifself.buf[0:3] ==b"BZh"andself.buf[4:10] ==b"1AY&SY":
return"bz2"
elifself.buf.startswith((b"\x5d\x00\x00\x80", b"\xfd7zXZ")):
return"xz"
else:
return"tar"
defclose(self):
self.fileobj.close()
# class StreamProxy
#------------------------
# Extraction file object
#------------------------
class_FileInFile(object):
"""A thin wrapper around an existing file object that
provides a part of its data as an individual file
object.
"""
def__init__(self, fileobj, offset, size, name, blockinfo=None):
self.fileobj=fileobj
self.offset=offset
self.size=size
self.position=0
self.name=name
self.closed=False
ifblockinfoisNone:
blockinfo= [(0, size)]
# Construct a map with data and zero blocks.
self.map_index=0
self.map= []
lastpos=0
realpos=self.offset
foroffset, sizeinblockinfo:
ifoffset>lastpos:
self.map.append((False, lastpos, offset, None))
self.map.append((True, offset, offset+size, realpos))
realpos+=size
lastpos=offset+size
iflastpos<self.size:
self.map.append((False, lastpos, self.size, None))
defflush(self):
pass
@property
defmode(self):
return'rb'
defreadable(self):
returnTrue
defwritable(self):
returnFalse
defseekable(self):
returnself.fileobj.seekable()
deftell(self):
"""Return the current file position.
"""
returnself.position
defseek(self, position, whence=io.SEEK_SET):
"""Seek to a position in the file.
"""
ifwhence==io.SEEK_SET:
self.position=min(max(position, 0), self.size)
elifwhence==io.SEEK_CUR:
ifposition<0:
self.position=max(self.position+position, 0)
else:
self.position=min(self.position+position, self.size)
elifwhence==io.SEEK_END:
self.position=max(min(self.size+position, self.size), 0)
else:
raiseValueError("Invalid argument")
returnself.position
defread(self, size=None):
"""Read data from the file.
"""
ifsizeisNone:
size=self.size-self.position
else:
size=min(size, self.size-self.position)
buf=b""
whilesize>0:
whileTrue:
data, start, stop, offset=self.map[self.map_index]
ifstart<=self.position<stop:
break
else:
self.map_index+=1
ifself.map_index==len(self.map):
self.map_index=0
length=min(size, stop-self.position)
ifdata:
self.fileobj.seek(offset+ (self.position-start))
b=self.fileobj.read(length)
iflen(b) !=length:
raiseReadError("unexpected end of data")
buf+=b
else:
buf+=NUL*length
size-=length
self.position+=length
returnbuf
defreadinto(self, b):
buf=self.read(len(b))
b[:len(buf)] =buf
returnlen(buf)
defclose(self):
self.closed=True
#class _FileInFile
classExFileObject(io.BufferedReader):
def__init__(self, tarfile, tarinfo):
fileobj=_FileInFile(tarfile.fileobj, tarinfo.offset_data,
tarinfo.size, tarinfo.name, tarinfo.sparse)
super().__init__(fileobj)
#class ExFileObject
#-----------------------------
# extraction filters (PEP 706)
#-----------------------------
classFilterError(TarError):
pass
classAbsolutePathError(FilterError):
def__init__(self, tarinfo):
self.tarinfo=tarinfo
super().__init__(f'member {tarinfo.name!r} has an absolute path')
classOutsideDestinationError(FilterError):
def__init__(self, tarinfo, path):
self.tarinfo=tarinfo
self._path=path
super().__init__(f'{tarinfo.name!r} would be extracted to {path!r}, '
+'which is outside the destination')
classSpecialFileError(FilterError):
def__init__(self, tarinfo):
self.tarinfo=tarinfo
super().__init__(f'{tarinfo.name!r} is a special file')
classAbsoluteLinkError(FilterError):
def__init__(self, tarinfo):
self.tarinfo=tarinfo
super().__init__(f'{tarinfo.name!r} is a link to an absolute path')
classLinkOutsideDestinationError(FilterError):
def__init__(self, tarinfo, path):
self.tarinfo=tarinfo
self._path=path
super().__init__(f'{tarinfo.name!r} would link to {path!r}, '
+'which is outside the destination')
def_get_filtered_attrs(member, dest_path, for_data=True):
new_attrs= {}
name=member.name
dest_path=os.path.realpath(dest_path)
# Strip leading / (tar's directory separator) from filenames.
# Include os.sep (target OS directory separator) as well.
ifname.startswith(('/', os.sep)):
name=new_attrs['name'] =member.path.lstrip('/'+os.sep)
ifos.path.isabs(name):
# Path is absolute even after stripping.
# For example, 'C:/foo' on Windows.
raiseAbsolutePathError(member)
# Ensure we stay in the destination
target_path=os.path.realpath(os.path.join(dest_path, name))
ifos.path.commonpath([target_path, dest_path]) !=dest_path:
raiseOutsideDestinationError(member, target_path)
# Limit permissions (no high bits, and go-w)
mode=member.mode
ifmodeisnotNone:
# Strip high bits & group/other write bits
mode=mode&0o755
iffor_data:
# For data, handle permissions & file types
ifmember.isreg() ormember.islnk():
ifnotmode&0o100:
# Clear executable bits if not executable by user
mode&=~0o111
# Ensure owner can read & write
mode|=0o600
elifmember.isdir() ormember.issym():
# Ignore mode for directories & symlinks
mode=None
else:
# Reject special files
raiseSpecialFileError(member)
ifmode!=member.mode:
new_attrs['mode'] =mode
iffor_data:
# Ignore ownership for 'data'
ifmember.uidisnotNone:
new_attrs['uid'] =None
ifmember.gidisnotNone:
new_attrs['gid'] =None
ifmember.unameisnotNone:
new_attrs['uname'] =None
ifmember.gnameisnotNone:
new_attrs['gname'] =None
# Check link destination for 'data'
ifmember.islnk() ormember.issym():
ifos.path.isabs(member.linkname):
raiseAbsoluteLinkError(member)
ifmember.issym():
target_path=os.path.join(dest_path,
os.path.dirname(name),
member.linkname)
else:
target_path=os.path.join(dest_path,
member.linkname)
target_path=os.path.realpath(target_path)
ifos.path.commonpath([target_path, dest_path]) !=dest_path:
raiseLinkOutsideDestinationError(member, target_path)
returnnew_attrs
deffully_trusted_filter(member, dest_path):
returnmember
deftar_filter(member, dest_path):
new_attrs=_get_filtered_attrs(member, dest_path, False)
ifnew_attrs:
returnmember.replace(**new_attrs, deep=False)
returnmember
defdata_filter(member, dest_path):
new_attrs=_get_filtered_attrs(member, dest_path, True)
ifnew_attrs:
returnmember.replace(**new_attrs, deep=False)
returnmember
_NAMED_FILTERS= {
"fully_trusted": fully_trusted_filter,
"tar": tar_filter,
"data": data_filter,
}
#------------------
# Exported Classes
#------------------
# Sentinel for replace() defaults, meaning "don't change the attribute"
_KEEP=object()
# Header length is digits followed by a space.
_header_length_prefix_re=re.compile(br"([0-9]{1,20}) ")
classTarInfo(object):
"""Informational class which holds the details about an
archive member given by a tar header block.
TarInfo objects are returned by TarFile.getmember(),
TarFile.getmembers() and TarFile.gettarinfo() and are
usually created internally.
"""
__slots__=dict(
name='Name of the archive member.',
mode='Permission bits.',
uid='User ID of the user who originally stored this member.',
gid='Group ID of the user who originally stored this member.',
size='Size in bytes.',
mtime='Time of last modification.',
chksum='Header checksum.',
type= ('File type. type is usually one of these constants: '
'REGTYPE, AREGTYPE, LNKTYPE, SYMTYPE, DIRTYPE, FIFOTYPE, '
'CONTTYPE, CHRTYPE, BLKTYPE, GNUTYPE_SPARSE.'),
linkname= ('Name of the target file name, which is only present '
'in TarInfo objects of type LNKTYPE and SYMTYPE.'),
uname='User name.',
gname='Group name.',
devmajor='Device major number.',
devminor='Device minor number.',
offset='The tar header starts here.',
offset_data="The file's data starts here.",
pax_headers= ('A dictionary containing key-value pairs of an '
'associated pax extended header.'),
sparse='Sparse member information.',
_tarfile=None,
_sparse_structs=None,
_link_target=None,
)
def__init__(self, name=""):
"""Construct a TarInfo object. name is the optional name
of the member.
"""
self.name=name# member name
self.mode=0o644# file permissions
self.uid=0# user id
self.gid=0# group id
self.size=0# file size
self.mtime=0# modification time
self.chksum=0# header checksum
self.type=REGTYPE# member type
self.linkname=""# link name
self.uname=""# user name
self.gname=""# group name
self.devmajor=0# device major number
self.devminor=0# device minor number
self.offset=0# the tar header starts here
self.offset_data=0# the file's data starts here
self.sparse=None# sparse member information
self.pax_headers= {} # pax header information
@property
deftarfile(self):
importwarnings
warnings.warn(
'The undocumented "tarfile" attribute of TarInfo objects '
+'is deprecated and will be removed in Python 3.16',
DeprecationWarning, stacklevel=2)
returnself._tarfile
@tarfile.setter
deftarfile(self, tarfile):
importwarnings
warnings.warn(
'The undocumented "tarfile" attribute of TarInfo objects '
+'is deprecated and will be removed in Python 3.16',
DeprecationWarning, stacklevel=2)
self._tarfile=tarfile
@property
defpath(self):
'In pax headers, "name" is called "path".'
returnself.name
@path.setter
defpath(self, name):
self.name=name
@property
deflinkpath(self):
'In pax headers, "linkname" is called "linkpath".'
returnself.linkname
@linkpath.setter
deflinkpath(self, linkname):
self.linkname=linkname
def__repr__(self):
return"<%s %r at %#x>"% (self.__class__.__name__,self.name,id(self))
defreplace(self, *,
name=_KEEP, mtime=_KEEP, mode=_KEEP, linkname=_KEEP,
uid=_KEEP, gid=_KEEP, uname=_KEEP, gname=_KEEP,
deep=True, _KEEP=_KEEP):
"""Return a deep copy of self with the given attributes replaced.
"""
ifdeep:
result=copy.deepcopy(self)
else:
result=copy.copy(self)
ifnameisnot_KEEP:
result.name=name
ifmtimeisnot_KEEP:
result.mtime=mtime
ifmodeisnot_KEEP:
result.mode=mode
iflinknameisnot_KEEP:
result.linkname=linkname
ifuidisnot_KEEP:
result.uid=uid
ifgidisnot_KEEP:
result.gid=gid
ifunameisnot_KEEP:
result.uname=uname
ifgnameisnot_KEEP:
result.gname=gname
returnresult
defget_info(self):
"""Return the TarInfo's attributes as a dictionary.
"""
ifself.modeisNone:
mode=None
else:
mode=self.mode&0o7777
info= {
"name": self.name,
"mode": mode,
"uid": self.uid,
"gid": self.gid,
"size": self.size,
"mtime": self.mtime,
"chksum": self.chksum,
"type": self.type,
"linkname": self.linkname,
"uname": self.uname,
"gname": self.gname,
"devmajor": self.devmajor,
"devminor": self.devminor
}
