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Last active Aug 31, 2020
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patched cpython's supporting non-naive seeking on STORED compression method (no compression at all)
< self._expected_crc = zipinfo.CRC
> self._expected_crc = self._orig_crc = zipinfo.CRC
< self._expected_crc = None
> self._expected_crc = self._orig_crc = None
< def seek(self, offset, whence=0):
> def seek(self, offset, whence=os.SEEK_SET):
< if whence == 0: # Seek from start of file
> if whence == os.SEEK_SET:
< elif whence == 1: # Seek from current position
> elif whence == os.SEEK_CUR:
< elif whence == 2: # Seek from EOF
> elif whence == os.SEEK_END:
> self._expected_crc = self._orig_crc
> if read_offset > 0 and self._compress_type == ZIP_STORED:
> # disable CRC checking after first seeking - it would be invalid
> self._expected_crc = None
>, os.SEEK_CUR)
> self._left -= read_offset
> self._offset = read_offset = 0
Read and write ZIP files.
XXX references to utf-8 need further investigation.
import binascii
import importlib.util
import io
import itertools
import os
import posixpath
import shutil
import stat
import struct
import sys
import threading
import time
import contextlib
import zlib # We may need its compression method
crc32 = zlib.crc32
except ImportError:
zlib = None
crc32 = binascii.crc32
import bz2 # We may need its compression method
except ImportError:
bz2 = None
import lzma # We may need its compression method
except ImportError:
lzma = None
__all__ = ["BadZipFile", "BadZipfile", "error",
"is_zipfile", "ZipInfo", "ZipFile", "PyZipFile", "LargeZipFile",
class BadZipFile(Exception):
class LargeZipFile(Exception):
Raised when writing a zipfile, the zipfile requires ZIP64 extensions
and those extensions are disabled.
error = BadZipfile = BadZipFile # Pre-3.2 compatibility names
ZIP64_LIMIT = (1 << 31) - 1
ZIP_FILECOUNT_LIMIT = (1 << 16) - 1
ZIP_MAX_COMMENT = (1 << 16) - 1
# constants for Zip file compression methods
ZIP_BZIP2 = 12
# Other ZIP compression methods not supported
# we recognize (but not necessarily support) all features up to that version
# Below are some formats and associated data for reading/writing headers using
# the struct module. The names and structures of headers/records are those used
# in the PKWARE description of the ZIP file format:
# (URL valid as of January 2008)
# The "end of central directory" structure, magic number, size, and indices
# (section V.I in the format document)
structEndArchive = b"<4s4H2LH"
stringEndArchive = b"PK\005\006"
sizeEndCentDir = struct.calcsize(structEndArchive)
# These last two indices are not part of the structure as defined in the
# spec, but they are used internally by this module as a convenience
# The "central directory" structure, magic number, size, and indices
# of entries in the structure (section V.F in the format document)
structCentralDir = "<4s4B4HL2L5H2L"
stringCentralDir = b"PK\001\002"
sizeCentralDir = struct.calcsize(structCentralDir)
# indexes of entries in the central directory structure
_CD_TIME = 7
_CD_DATE = 8
_CD_CRC = 9
# The "local file header" structure, magic number, size, and indices
# (section V.A in the format document)
structFileHeader = "<4s2B4HL2L2H"
stringFileHeader = b"PK\003\004"
sizeFileHeader = struct.calcsize(structFileHeader)
_FH_CRC = 7
# The "Zip64 end of central directory locator" structure, magic number, and size
structEndArchive64Locator = "<4sLQL"
stringEndArchive64Locator = b"PK\x06\x07"
sizeEndCentDir64Locator = struct.calcsize(structEndArchive64Locator)
# The "Zip64 end of central directory" record, magic number, size, and indices
# (section V.G in the format document)
structEndArchive64 = "<4sQ2H2L4Q"
stringEndArchive64 = b"PK\x06\x06"
sizeEndCentDir64 = struct.calcsize(structEndArchive64)
_DD_SIGNATURE = 0x08074b50
_EXTRA_FIELD_STRUCT = struct.Struct('<HH')
def _strip_extra(extra, xids):
# Remove Extra Fields with specified IDs.
unpack = _EXTRA_FIELD_STRUCT.unpack
modified = False
buffer = []
start = i = 0
while i + 4 <= len(extra):
xid, xlen = unpack(extra[i : i + 4])
j = i + 4 + xlen
if xid in xids:
if i != start:
buffer.append(extra[start : i])
start = j
modified = True
i = j
if not modified:
return extra
return b''.join(buffer)
def _check_zipfile(fp):
if _EndRecData(fp):
return True # file has correct magic number
except OSError:
return False
def is_zipfile(filename):
"""Quickly see if a file is a ZIP file by checking the magic number.
The filename argument may be a file or file-like object too.
result = False
if hasattr(filename, "read"):
result = _check_zipfile(fp=filename)
with open(filename, "rb") as fp:
result = _check_zipfile(fp)
except OSError:
return result
def _EndRecData64(fpin, offset, endrec):
Read the ZIP64 end-of-archive records and use that to update endrec
try: - sizeEndCentDir64Locator, 2)
except OSError:
# If the seek fails, the file is not large enough to contain a ZIP64
# end-of-archive record, so just return the end record we were given.
return endrec
data =
if len(data) != sizeEndCentDir64Locator:
return endrec
sig, diskno, reloff, disks = struct.unpack(structEndArchive64Locator, data)
if sig != stringEndArchive64Locator:
return endrec
if diskno != 0 or disks > 1:
raise BadZipFile("zipfiles that span multiple disks are not supported")
# Assume no 'zip64 extensible data' - sizeEndCentDir64Locator - sizeEndCentDir64, 2)
data =
if len(data) != sizeEndCentDir64:
return endrec
sig, sz, create_version, read_version, disk_num, disk_dir, \
dircount, dircount2, dirsize, diroffset = \
struct.unpack(structEndArchive64, data)
if sig != stringEndArchive64:
return endrec
# Update the original endrec using data from the ZIP64 record
endrec[_ECD_SIGNATURE] = sig
endrec[_ECD_DISK_NUMBER] = disk_num
endrec[_ECD_DISK_START] = disk_dir
endrec[_ECD_ENTRIES_THIS_DISK] = dircount
endrec[_ECD_ENTRIES_TOTAL] = dircount2
endrec[_ECD_SIZE] = dirsize
endrec[_ECD_OFFSET] = diroffset
return endrec
def _EndRecData(fpin):
"""Return data from the "End of Central Directory" record, or None.
The data is a list of the nine items in the ZIP "End of central dir"
record followed by a tenth item, the file seek offset of this record."""
# Determine file size, 2)
filesize = fpin.tell()
# Check to see if this is ZIP file with no archive comment (the
# "end of central directory" structure should be the last item in the
# file if this is the case).
try:, 2)
except OSError:
return None
data =
if (len(data) == sizeEndCentDir and
data[0:4] == stringEndArchive and
data[-2:] == b"\000\000"):
# the signature is correct and there's no comment, unpack structure
endrec = struct.unpack(structEndArchive, data)
# Append a blank comment and record start offset
endrec.append(filesize - sizeEndCentDir)
# Try to read the "Zip64 end of central directory" structure
return _EndRecData64(fpin, -sizeEndCentDir, endrec)
# Either this is not a ZIP file, or it is a ZIP file with an archive
# comment. Search the end of the file for the "end of central directory"
# record signature. The comment is the last item in the ZIP file and may be
# up to 64K long. It is assumed that the "end of central directory" magic
# number does not appear in the comment.
maxCommentStart = max(filesize - (1 << 16) - sizeEndCentDir, 0), 0)
data =
start = data.rfind(stringEndArchive)
if start >= 0:
# found the magic number; attempt to unpack and interpret
recData = data[start:start+sizeEndCentDir]
if len(recData) != sizeEndCentDir:
# Zip file is corrupted.
return None
endrec = list(struct.unpack(structEndArchive, recData))
commentSize = endrec[_ECD_COMMENT_SIZE] #as claimed by the zip file
comment = data[start+sizeEndCentDir:start+sizeEndCentDir+commentSize]
endrec.append(maxCommentStart + start)
# Try to read the "Zip64 end of central directory" structure
return _EndRecData64(fpin, maxCommentStart + start - filesize,
# Unable to find a valid end of central directory structure
return None
class ZipInfo (object):
"""Class with attributes describing each file in the ZIP archive."""
__slots__ = (
def __init__(self, filename="NoName", date_time=(1980,1,1,0,0,0)):
self.orig_filename = filename # Original file name in archive
# Terminate the file name at the first null byte. Null bytes in file
# names are used as tricks by viruses in archives.
null_byte = filename.find(chr(0))
if null_byte >= 0:
filename = filename[0:null_byte]
# This is used to ensure paths in generated ZIP files always use
# forward slashes as the directory separator, as required by the
# ZIP format specification.
if os.sep != "/" and os.sep in filename:
filename = filename.replace(os.sep, "/")
self.filename = filename # Normalized file name
self.date_time = date_time # year, month, day, hour, min, sec
if date_time[0] < 1980:
raise ValueError('ZIP does not support timestamps before 1980')
# Standard values:
self.compress_type = ZIP_STORED # Type of compression for the file
self._compresslevel = None # Level for the compressor
self.comment = b"" # Comment for each file
self.extra = b"" # ZIP extra data
if sys.platform == 'win32':
self.create_system = 0 # System which created ZIP archive
# Assume everything else is unix-y
self.create_system = 3 # System which created ZIP archive
self.create_version = DEFAULT_VERSION # Version which created ZIP archive
self.extract_version = DEFAULT_VERSION # Version needed to extract archive
self.reserved = 0 # Must be zero
self.flag_bits = 0 # ZIP flag bits
self.volume = 0 # Volume number of file header
self.internal_attr = 0 # Internal attributes
self.external_attr = 0 # External file attributes
self.compress_size = 0 # Size of the compressed file
self.file_size = 0 # Size of the uncompressed file
# Other attributes are set by class ZipFile:
# header_offset Byte offset to the file header
# CRC CRC-32 of the uncompressed file
def __repr__(self):
result = ['<%s filename=%r' % (self.__class__.__name__, self.filename)]
if self.compress_type != ZIP_STORED:
result.append(' compress_type=%s' %
hi = self.external_attr >> 16
lo = self.external_attr & 0xFFFF
if hi:
result.append(' filemode=%r' % stat.filemode(hi))
if lo:
result.append(' external_attr=%#x' % lo)
isdir = self.is_dir()
if not isdir or self.file_size:
result.append(' file_size=%r' % self.file_size)
if ((not isdir or self.compress_size) and
(self.compress_type != ZIP_STORED or
self.file_size != self.compress_size)):
result.append(' compress_size=%r' % self.compress_size)
return ''.join(result)
def FileHeader(self, zip64=None):
"""Return the per-file header as a bytes object."""
dt = self.date_time
dosdate = (dt[0] - 1980) << 9 | dt[1] << 5 | dt[2]
dostime = dt[3] << 11 | dt[4] << 5 | (dt[5] // 2)
if self.flag_bits & 0x08:
# Set these to zero because we write them after the file data
CRC = compress_size = file_size = 0
CRC = self.CRC
compress_size = self.compress_size
file_size = self.file_size
extra = self.extra
min_version = 0
if zip64 is None:
zip64 = file_size > ZIP64_LIMIT or compress_size > ZIP64_LIMIT
if zip64:
fmt = '<HHQQ'
extra = extra + struct.pack(fmt,
1, struct.calcsize(fmt)-4, file_size, compress_size)
if file_size > ZIP64_LIMIT or compress_size > ZIP64_LIMIT:
if not zip64:
raise LargeZipFile("Filesize would require ZIP64 extensions")
# File is larger than what fits into a 4 byte integer,
# fall back to the ZIP64 extension
file_size = 0xffffffff
compress_size = 0xffffffff
min_version = ZIP64_VERSION
if self.compress_type == ZIP_BZIP2:
min_version = max(BZIP2_VERSION, min_version)
elif self.compress_type == ZIP_LZMA:
min_version = max(LZMA_VERSION, min_version)
self.extract_version = max(min_version, self.extract_version)
self.create_version = max(min_version, self.create_version)
filename, flag_bits = self._encodeFilenameFlags()
header = struct.pack(structFileHeader, stringFileHeader,
self.extract_version, self.reserved, flag_bits,
self.compress_type, dostime, dosdate, CRC,
compress_size, file_size,
len(filename), len(extra))
return header + filename + extra
def _encodeFilenameFlags(self):
return self.filename.encode('ascii'), self.flag_bits
except UnicodeEncodeError:
return self.filename.encode('utf-8'), self.flag_bits | 0x800
def _decodeExtra(self):
# Try to decode the extra field.
extra = self.extra
unpack = struct.unpack
while len(extra) >= 4:
tp, ln = unpack('<HH', extra[:4])
if ln+4 > len(extra):
raise BadZipFile("Corrupt extra field %04x (size=%d)" % (tp, ln))
if tp == 0x0001:
data = extra[4:ln+4]
# ZIP64 extension (large files and/or large archives)
if self.file_size in (0xFFFF_FFFF_FFFF_FFFF, 0xFFFF_FFFF):
field = "File size"
self.file_size, = unpack('<Q', data[:8])
data = data[8:]
if self.compress_size == 0xFFFF_FFFF:
field = "Compress size"
self.compress_size, = unpack('<Q', data[:8])
data = data[8:]
if self.header_offset == 0xFFFF_FFFF:
field = "Header offset"
self.header_offset, = unpack('<Q', data[:8])
except struct.error:
raise BadZipFile(f"Corrupt zip64 extra field. "
f"{field} not found.") from None
extra = extra[ln+4:]
def from_file(cls, filename, arcname=None, *, strict_timestamps=True):
"""Construct an appropriate ZipInfo for a file on the filesystem.
filename should be the path to a file or directory on the filesystem.
arcname is the name which it will have within the archive (by default,
this will be the same as filename, but without a drive letter and with
leading path separators removed).
if isinstance(filename, os.PathLike):
filename = os.fspath(filename)
st = os.stat(filename)
isdir = stat.S_ISDIR(st.st_mode)
mtime = time.localtime(st.st_mtime)
date_time = mtime[0:6]
if not strict_timestamps and date_time[0] < 1980:
date_time = (1980, 1, 1, 0, 0, 0)
elif not strict_timestamps and date_time[0] > 2107:
date_time = (2107, 12, 31, 23, 59, 59)
# Create ZipInfo instance to store file information
if arcname is None:
arcname = filename
arcname = os.path.normpath(os.path.splitdrive(arcname)[1])
while arcname[0] in (os.sep, os.altsep):
arcname = arcname[1:]
if isdir:
arcname += '/'
zinfo = cls(arcname, date_time)
zinfo.external_attr = (st.st_mode & 0xFFFF) << 16 # Unix attributes
if isdir:
zinfo.file_size = 0
zinfo.external_attr |= 0x10 # MS-DOS directory flag
zinfo.file_size = st.st_size
return zinfo
def is_dir(self):
"""Return True if this archive member is a directory."""
return self.filename[-1] == '/'
# ZIP encryption uses the CRC32 one-byte primitive for scrambling some
# internal keys. We noticed that a direct implementation is faster than
# relying on binascii.crc32().
_crctable = None
def _gen_crc(crc):
for j in range(8):
if crc & 1:
crc = (crc >> 1) ^ 0xEDB88320
crc >>= 1
return crc
# ZIP supports a password-based form of encryption. Even though known
# plaintext attacks have been found against it, it is still useful
# to be able to get data out of such a file.
# Usage:
# zd = _ZipDecrypter(mypwd)
# plain_bytes = zd(cypher_bytes)
def _ZipDecrypter(pwd):
key0 = 305419896
key1 = 591751049
key2 = 878082192
global _crctable
if _crctable is None:
_crctable = list(map(_gen_crc, range(256)))
crctable = _crctable
def crc32(ch, crc):
"""Compute the CRC32 primitive on one byte."""
return (crc >> 8) ^ crctable[(crc ^ ch) & 0xFF]
def update_keys(c):
nonlocal key0, key1, key2
key0 = crc32(c, key0)
key1 = (key1 + (key0 & 0xFF)) & 0xFFFFFFFF
key1 = (key1 * 134775813 + 1) & 0xFFFFFFFF
key2 = crc32(key1 >> 24, key2)
for p in pwd:
def decrypter(data):
"""Decrypt a bytes object."""
result = bytearray()
append = result.append
for c in data:
k = key2 | 2
c ^= ((k * (k^1)) >> 8) & 0xFF
return bytes(result)
return decrypter
class LZMACompressor:
def __init__(self):
self._comp = None
def _init(self):
props = lzma._encode_filter_properties({'id': lzma.FILTER_LZMA1})
self._comp = lzma.LZMACompressor(lzma.FORMAT_RAW, filters=[
lzma._decode_filter_properties(lzma.FILTER_LZMA1, props)
return struct.pack('<BBH', 9, 4, len(props)) + props
def compress(self, data):
if self._comp is None:
return self._init() + self._comp.compress(data)
return self._comp.compress(data)
def flush(self):
if self._comp is None:
return self._init() + self._comp.flush()
return self._comp.flush()
class LZMADecompressor:
def __init__(self):
self._decomp = None
self._unconsumed = b''
self.eof = False
def decompress(self, data):
if self._decomp is None:
self._unconsumed += data
if len(self._unconsumed) <= 4:
return b''
psize, = struct.unpack('<H', self._unconsumed[2:4])
if len(self._unconsumed) <= 4 + psize:
return b''
self._decomp = lzma.LZMADecompressor(lzma.FORMAT_RAW, filters=[
self._unconsumed[4:4 + psize])
data = self._unconsumed[4 + psize:]
del self._unconsumed
result = self._decomp.decompress(data)
self.eof = self._decomp.eof
return result
compressor_names = {
0: 'store',
1: 'shrink',
2: 'reduce',
3: 'reduce',
4: 'reduce',
5: 'reduce',
6: 'implode',
7: 'tokenize',
8: 'deflate',
9: 'deflate64',
10: 'implode',
12: 'bzip2',
14: 'lzma',
18: 'terse',
19: 'lz77',
97: 'wavpack',
98: 'ppmd',
def _check_compression(compression):
if compression == ZIP_STORED:
elif compression == ZIP_DEFLATED:
if not zlib:
raise RuntimeError(
"Compression requires the (missing) zlib module")
elif compression == ZIP_BZIP2:
if not bz2:
raise RuntimeError(
"Compression requires the (missing) bz2 module")
elif compression == ZIP_LZMA:
if not lzma:
raise RuntimeError(
"Compression requires the (missing) lzma module")
raise NotImplementedError("That compression method is not supported")
def _get_compressor(compress_type, compresslevel=None):
if compress_type == ZIP_DEFLATED:
if compresslevel is not None:
return zlib.compressobj(compresslevel, zlib.DEFLATED, -15)
return zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION, zlib.DEFLATED, -15)
elif compress_type == ZIP_BZIP2:
if compresslevel is not None:
return bz2.BZ2Compressor(compresslevel)
return bz2.BZ2Compressor()
# compresslevel is ignored for ZIP_LZMA
elif compress_type == ZIP_LZMA:
return LZMACompressor()
return None
def _get_decompressor(compress_type):
if compress_type == ZIP_STORED:
return None
elif compress_type == ZIP_DEFLATED:
return zlib.decompressobj(-15)
elif compress_type == ZIP_BZIP2:
return bz2.BZ2Decompressor()
elif compress_type == ZIP_LZMA:
return LZMADecompressor()
descr = compressor_names.get(compress_type)
if descr:
raise NotImplementedError("compression type %d (%s)" % (compress_type, descr))
raise NotImplementedError("compression type %d" % (compress_type,))
class _SharedFile:
def __init__(self, file, pos, close, lock, writing):
self._file = file
self._pos = pos
self._close = close
self._lock = lock
self._writing = writing
self.seekable = file.seekable
self.tell = file.tell
def seek(self, offset, whence=0):
with self._lock:
if self._writing():
raise ValueError("Can't reposition in the ZIP file while "
"there is an open writing handle on it. "
"Close the writing handle before trying to read."), whence)
self._pos = self._file.tell()
return self._pos
def read(self, n=-1):
with self._lock:
if self._writing():
raise ValueError("Can't read from the ZIP file while there "
"is an open writing handle on it. "
"Close the writing handle before trying to read.")
data =
self._pos = self._file.tell()
return data
def close(self):
if self._file is not None:
fileobj = self._file
self._file = None
# Provide the tell method for unseekable stream
class _Tellable:
def __init__(self, fp):
self.fp = fp
self.offset = 0
def write(self, data):
n = self.fp.write(data)
self.offset += n
return n
def tell(self):
return self.offset
def flush(self):
def close(self):
class ZipExtFile(io.BufferedIOBase):
"""File-like object for reading an archive member.
Is returned by
# Max size supported by decompressor.
MAX_N = 1 << 31 - 1
# Read from compressed files in 4k blocks.
# Chunk size to read during seek
MAX_SEEK_READ = 1 << 24
def __init__(self, fileobj, mode, zipinfo, pwd=None,
self._fileobj = fileobj
self._pwd = pwd
self._close_fileobj = close_fileobj
self._compress_type = zipinfo.compress_type
self._compress_left = zipinfo.compress_size
self._left = zipinfo.file_size
self._decompressor = _get_decompressor(self._compress_type)
self._eof = False
self._readbuffer = b''
self._offset = 0
self.newlines = None
self.mode = mode = zipinfo.filename
if hasattr(zipinfo, 'CRC'):
self._expected_crc = self._orig_crc = zipinfo.CRC
self._running_crc = crc32(b'')
self._expected_crc = self._orig_crc = None
self._seekable = False
if fileobj.seekable():
self._orig_compress_start = fileobj.tell()
self._orig_compress_size = zipinfo.compress_size
self._orig_file_size = zipinfo.file_size
self._orig_start_crc = self._running_crc
self._seekable = True
except AttributeError:
self._decrypter = None
if pwd:
if zipinfo.flag_bits & 0x8:
# compare against the file type from extended local headers
check_byte = (zipinfo._raw_time >> 8) & 0xff
# compare against the CRC otherwise
check_byte = (zipinfo.CRC >> 24) & 0xff
h = self._init_decrypter()
if h != check_byte:
raise RuntimeError("Bad password for file %r" % zipinfo.orig_filename)
def _init_decrypter(self):
self._decrypter = _ZipDecrypter(self._pwd)
# The first 12 bytes in the cypher stream is an encryption header
# used to strengthen the algorithm. The first 11 bytes are
# completely random, while the 12th contains the MSB of the CRC,
# or the MSB of the file time depending on the header type
# and is used to check the correctness of the password.
header =
self._compress_left -= 12
return self._decrypter(header)[11]
def __repr__(self):
result = ['<%s.%s' % (self.__class__.__module__,
if not self.closed:
result.append(' name=%r mode=%r' % (, self.mode))
if self._compress_type != ZIP_STORED:
result.append(' compress_type=%s' %
result.append(' [closed]')
return ''.join(result)
def readline(self, limit=-1):
"""Read and return a line from the stream.
If limit is specified, at most limit bytes will be read.
if limit < 0:
# Shortcut common case - newline found in buffer.
i = self._readbuffer.find(b'\n', self._offset) + 1
if i > 0:
line = self._readbuffer[self._offset: i]
self._offset = i
return line
return io.BufferedIOBase.readline(self, limit)
def peek(self, n=1):
"""Returns buffered bytes without advancing the position."""
if n > len(self._readbuffer) - self._offset:
chunk =
if len(chunk) > self._offset:
self._readbuffer = chunk + self._readbuffer[self._offset:]
self._offset = 0
self._offset -= len(chunk)
# Return up to 512 bytes to reduce allocation overhead for tight loops.
return self._readbuffer[self._offset: self._offset + 512]
def readable(self):
if self.closed:
raise ValueError("I/O operation on closed file.")
return True
def read(self, n=-1):
"""Read and return up to n bytes.
If the argument is omitted, None, or negative, data is read and returned until EOF is reached.
if self.closed:
raise ValueError("read from closed file.")
if n is None or n < 0:
buf = self._readbuffer[self._offset:]
self._readbuffer = b''
self._offset = 0
while not self._eof:
buf += self._read1(self.MAX_N)
return buf
end = n + self._offset
if end < len(self._readbuffer):
buf = self._readbuffer[self._offset:end]
self._offset = end
return buf
n = end - len(self._readbuffer)
buf = self._readbuffer[self._offset:]
self._readbuffer = b''
self._offset = 0
while n > 0 and not self._eof:
data = self._read1(n)
if n < len(data):
self._readbuffer = data
self._offset = n
buf += data[:n]
buf += data
n -= len(data)
return buf
def _update_crc(self, newdata):
# Update the CRC using the given data.
if self._expected_crc is None:
# No need to compute the CRC if we don't have a reference value
self._running_crc = crc32(newdata, self._running_crc)
# Check the CRC if we're at the end of the file
if self._eof and self._running_crc != self._expected_crc:
raise BadZipFile("Bad CRC-32 for file %r" %
def read1(self, n):
"""Read up to n bytes with at most one read() system call."""
if n is None or n < 0:
buf = self._readbuffer[self._offset:]
self._readbuffer = b''
self._offset = 0
while not self._eof:
data = self._read1(self.MAX_N)
if data:
buf += data
return buf
end = n + self._offset
if end < len(self._readbuffer):
buf = self._readbuffer[self._offset:end]
self._offset = end
return buf
n = end - len(self._readbuffer)
buf = self._readbuffer[self._offset:]
self._readbuffer = b''
self._offset = 0
if n > 0:
while not self._eof:
data = self._read1(n)
if n < len(data):
self._readbuffer = data
self._offset = n
buf += data[:n]
if data:
buf += data
return buf
def _read1(self, n):
# Read up to n compressed bytes with at most one read() system call,
# decrypt and decompress them.
if self._eof or n <= 0:
return b''
# Read from file.
if self._compress_type == ZIP_DEFLATED:
## Handle unconsumed data.
data = self._decompressor.unconsumed_tail
if n > len(data):
data += self._read2(n - len(data))
data = self._read2(n)
if self._compress_type == ZIP_STORED:
self._eof = self._compress_left <= 0
elif self._compress_type == ZIP_DEFLATED:
n = max(n, self.MIN_READ_SIZE)
data = self._decompressor.decompress(data, n)
self._eof = (self._decompressor.eof or
self._compress_left <= 0 and
not self._decompressor.unconsumed_tail)
if self._eof:
data += self._decompressor.flush()
data = self._decompressor.decompress(data)
self._eof = self._decompressor.eof or self._compress_left <= 0
data = data[:self._left]
self._left -= len(data)
if self._left <= 0:
self._eof = True
return data
def _read2(self, n):
if self._compress_left <= 0:
return b''
n = max(n, self.MIN_READ_SIZE)
n = min(n, self._compress_left)
data =
self._compress_left -= len(data)
if not data:
raise EOFError
if self._decrypter is not None:
data = self._decrypter(data)
return data
def close(self):
if self._close_fileobj:
def seekable(self):
if self.closed:
raise ValueError("I/O operation on closed file.")
return self._seekable
def seek(self, offset, whence=os.SEEK_SET):
if self.closed:
raise ValueError("seek on closed file.")
if not self._seekable:
raise io.UnsupportedOperation("underlying stream is not seekable")
curr_pos = self.tell()
if whence == os.SEEK_SET:
new_pos = offset
elif whence == os.SEEK_CUR:
new_pos = curr_pos + offset
elif whence == os.SEEK_END:
new_pos = self._orig_file_size + offset
raise ValueError("whence must be os.SEEK_SET (0), "
"os.SEEK_CUR (1), or os.SEEK_END (2)")
if new_pos > self._orig_file_size:
new_pos = self._orig_file_size
if new_pos < 0:
new_pos = 0
read_offset = new_pos - curr_pos
buff_offset = read_offset + self._offset
if buff_offset >= 0 and buff_offset < len(self._readbuffer):
# Just move the _offset index if the new position is in the _readbuffer
self._offset = buff_offset
read_offset = 0
elif read_offset < 0:
# Position is before the current position. Reset the ZipExtFile
self._running_crc = self._orig_start_crc
self._expected_crc = self._orig_crc
self._compress_left = self._orig_compress_size
self._left = self._orig_file_size
self._readbuffer = b''
self._offset = 0
self._decompressor = _get_decompressor(self._compress_type)
self._eof = False
read_offset = new_pos
if self._decrypter is not None:
if read_offset > 0 and self._compress_type == ZIP_STORED:
# disable CRC checking after first seeking - it would be invalid
self._expected_crc = None, os.SEEK_CUR)
self._left -= read_offset
self._offset = read_offset = 0
while read_offset > 0:
read_len = min(self.MAX_SEEK_READ, read_offset)
read_offset -= read_len
return self.tell()
def tell(self):
if self.closed:
raise ValueError("tell on closed file.")
if not self._seekable:
raise io.UnsupportedOperation("underlying stream is not seekable")
filepos = self._orig_file_size - self._left - len(self._readbuffer) + self._offset
return filepos
class _ZipWriteFile(io.BufferedIOBase):
def __init__(self, zf, zinfo, zip64):
self._zinfo = zinfo
self._zip64 = zip64
self._zipfile = zf
self._compressor = _get_compressor(zinfo.compress_type,
self._file_size = 0
self._compress_size = 0
self._crc = 0
def _fileobj(self):
return self._zipfile.fp
def writable(self):
return True
def write(self, data):
if self.closed:
raise ValueError('I/O operation on closed file.')
nbytes = len(data)
self._file_size += nbytes
self._crc = crc32(data, self._crc)
if self._compressor:
data = self._compressor.compress(data)
self._compress_size += len(data)
return nbytes
def close(self):
if self.closed:
# Flush any data from the compressor, and update header info
if self._compressor:
buf = self._compressor.flush()
self._compress_size += len(buf)
self._zinfo.compress_size = self._compress_size
self._zinfo.compress_size = self._file_size
self._zinfo.CRC = self._crc
self._zinfo.file_size = self._file_size
# Write updated header info
if self._zinfo.flag_bits & 0x08:
# Write CRC and file sizes after the file data
fmt = '<LLQQ' if self._zip64 else '<LLLL'
self._fileobj.write(struct.pack(fmt, _DD_SIGNATURE, self._zinfo.CRC,
self._zinfo.compress_size, self._zinfo.file_size))
self._zipfile.start_dir = self._fileobj.tell()
if not self._zip64:
if self._file_size > ZIP64_LIMIT:
raise RuntimeError(
'File size unexpectedly exceeded ZIP64 limit')
if self._compress_size > ZIP64_LIMIT:
raise RuntimeError(
'Compressed size unexpectedly exceeded ZIP64 limit')
# Seek backwards and write file header (which will now include
# correct CRC and file sizes)
# Preserve current position in file
self._zipfile.start_dir = self._fileobj.tell()
# Successfully written: Add file to our caches
self._zipfile.NameToInfo[self._zinfo.filename] = self._zinfo
self._zipfile._writing = False
class ZipFile:
""" Class with methods to open, read, write, close, list zip files.
z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=True,
file: Either the path to the file, or a file-like object.
If it is a path, the file will be opened and closed by ZipFile.
mode: The mode can be either read 'r', write 'w', exclusive create 'x',
or append 'a'.
compression: ZIP_STORED (no compression), ZIP_DEFLATED (requires zlib),
ZIP_BZIP2 (requires bz2) or ZIP_LZMA (requires lzma).
allowZip64: if True ZipFile will create files with ZIP64 extensions when
needed, otherwise it will raise an exception when this would
be necessary.
compresslevel: None (default for the given compression type) or an integer
specifying the level to pass to the compressor.
When using ZIP_STORED or ZIP_LZMA this keyword has no effect.
When using ZIP_DEFLATED integers 0 through 9 are accepted.
When using ZIP_BZIP2 integers 1 through 9 are accepted.
fp = None # Set here since __del__ checks it
_windows_illegal_name_trans_table = None
def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=True,
compresslevel=None, *, strict_timestamps=True):
"""Open the ZIP file with mode read 'r', write 'w', exclusive create 'x',
or append 'a'."""
if mode not in ('r', 'w', 'x', 'a'):
raise ValueError("ZipFile requires mode 'r', 'w', 'x', or 'a'")
self._allowZip64 = allowZip64
self._didModify = False
self.debug = 0 # Level of printing: 0 through 3
self.NameToInfo = {} # Find file info given name
self.filelist = [] # List of ZipInfo instances for archive
self.compression = compression # Method of compression
self.compresslevel = compresslevel
self.mode = mode
self.pwd = None
self._comment = b''
self._strict_timestamps = strict_timestamps
# Check if we were passed a file-like object
if isinstance(file, os.PathLike):
file = os.fspath(file)
if isinstance(file, str):
# No, it's a filename
self._filePassed = 0
self.filename = file
modeDict = {'r' : 'rb', 'w': 'w+b', 'x': 'x+b', 'a' : 'r+b',
'r+b': 'w+b', 'w+b': 'wb', 'x+b': 'xb'}
filemode = modeDict[mode]
while True:
self.fp =, filemode)
except OSError:
if filemode in modeDict:
filemode = modeDict[filemode]
self._filePassed = 1
self.fp = file
self.filename = getattr(file, 'name', None)
self._fileRefCnt = 1
self._lock = threading.RLock()
self._seekable = True
self._writing = False
if mode == 'r':
elif mode in ('w', 'x'):
# set the modified flag so central directory gets written
# even if no files are added to the archive
self._didModify = True
self.start_dir = self.fp.tell()
except (AttributeError, OSError):
self.fp = _Tellable(self.fp)
self.start_dir = 0
self._seekable = False
# Some file-like objects can provide tell() but not seek()
except (AttributeError, OSError):
self._seekable = False
elif mode == 'a':
# See if file is a zip file
# seek to start of directory and overwrite
except BadZipFile:
# file is not a zip file, just append, 2)
# set the modified flag so central directory gets written
# even if no files are added to the archive
self._didModify = True
self.start_dir = self.fp.tell()
raise ValueError("Mode must be 'r', 'w', 'x', or 'a'")
fp = self.fp
self.fp = None
def __enter__(self):
return self
def __exit__(self, type, value, traceback):
def __repr__(self):
result = ['<%s.%s' % (self.__class__.__module__,
if self.fp is not None:
if self._filePassed:
result.append(' file=%r' % self.fp)
elif self.filename is not None:
result.append(' filename=%r' % self.filename)
result.append(' mode=%r' % self.mode)
result.append(' [closed]')
return ''.join(result)
def _RealGetContents(self):
"""Read in the table of contents for the ZIP file."""
fp = self.fp
endrec = _EndRecData(fp)
except OSError:
raise BadZipFile("File is not a zip file")
if not endrec:
raise BadZipFile("File is not a zip file")
if self.debug > 1:
size_cd = endrec[_ECD_SIZE] # bytes in central directory
offset_cd = endrec[_ECD_OFFSET] # offset of central directory
self._comment = endrec[_ECD_COMMENT] # archive comment
# "concat" is zero, unless zip was concatenated to another file
concat = endrec[_ECD_LOCATION] - size_cd - offset_cd
if endrec[_ECD_SIGNATURE] == stringEndArchive64:
# If Zip64 extension structures are present, account for them
concat -= (sizeEndCentDir64 + sizeEndCentDir64Locator)
if self.debug > 2:
inferred = concat + offset_cd
print("given, inferred, offset", offset_cd, inferred, concat)
# self.start_dir: Position of start of central directory
self.start_dir = offset_cd + concat, 0)
data =
fp = io.BytesIO(data)
total = 0
while total < size_cd:
centdir =
if len(centdir) != sizeCentralDir:
raise BadZipFile("Truncated central directory")
centdir = struct.unpack(structCentralDir, centdir)
if centdir[_CD_SIGNATURE] != stringCentralDir:
raise BadZipFile("Bad magic number for central directory")
if self.debug > 2:
filename =[_CD_FILENAME_LENGTH])
flags = centdir[5]
if flags & 0x800:
# UTF-8 file names extension
filename = filename.decode('utf-8')
# Historical ZIP filename encoding
filename = filename.decode('cp437')
# Create ZipInfo instance to store file information
x = ZipInfo(filename)
x.comment =[_CD_COMMENT_LENGTH])
x.header_offset = centdir[_CD_LOCAL_HEADER_OFFSET]
(x.create_version, x.create_system, x.extract_version, x.reserved,
x.flag_bits, x.compress_type, t, d,
x.CRC, x.compress_size, x.file_size) = centdir[1:12]
if x.extract_version > MAX_EXTRACT_VERSION:
raise NotImplementedError("zip file version %.1f" %
(x.extract_version / 10))
x.volume, x.internal_attr, x.external_attr = centdir[15:18]
# Convert date/time code to (year, month, day, hour, min, sec)
x._raw_time = t
x.date_time = ( (d>>9)+1980, (d>>5)&0xF, d&0x1F,
t>>11, (t>>5)&0x3F, (t&0x1F) * 2 )
x.header_offset = x.header_offset + concat
self.NameToInfo[x.filename] = x
# update total bytes read from central directory
total = (total + sizeCentralDir + centdir[_CD_FILENAME_LENGTH]
+ centdir[_CD_COMMENT_LENGTH])
if self.debug > 2:
print("total", total)
def namelist(self):
"""Return a list of file names in the archive."""
return [data.filename for data in self.filelist]
def infolist(self):
"""Return a list of class ZipInfo instances for files in the
return self.filelist
def printdir(self, file=None):
"""Print a table of contents for the zip file."""
print("%-46s %19s %12s" % ("File Name", "Modified ", "Size"),
for zinfo in self.filelist:
date = "%d-%02d-%02d %02d:%02d:%02d" % zinfo.date_time[:6]
print("%-46s %s %12d" % (zinfo.filename, date, zinfo.file_size),
def testzip(self):
"""Read all the files and check the CRC."""
chunk_size = 2 ** 20
for zinfo in self.filelist:
# Read by chunks, to avoid an OverflowError or a
# MemoryError with very large embedded files.
with, "r") as f:
while # Check CRC-32
except BadZipFile:
return zinfo.filename
def getinfo(self, name):
"""Return the instance of ZipInfo given 'name'."""
info = self.NameToInfo.get(name)
if info is None:
raise KeyError(
'There is no item named %r in the archive' % name)
return info
def setpassword(self, pwd):
"""Set default password for encrypted files."""
if pwd and not isinstance(pwd, bytes):
raise TypeError("pwd: expected bytes, got %s" % type(pwd).__name__)
if pwd:
self.pwd = pwd
self.pwd = None
def comment(self):
"""The comment text associated with the ZIP file."""
return self._comment
def comment(self, comment):
if not isinstance(comment, bytes):
raise TypeError("comment: expected bytes, got %s" % type(comment).__name__)
# check for valid comment length
if len(comment) > ZIP_MAX_COMMENT:
import warnings
warnings.warn('Archive comment is too long; truncating to %d bytes'
% ZIP_MAX_COMMENT, stacklevel=2)
comment = comment[:ZIP_MAX_COMMENT]
self._comment = comment
self._didModify = True
def read(self, name, pwd=None):
"""Return file bytes for name."""
with, "r", pwd) as fp:
def open(self, name, mode="r", pwd=None, *, force_zip64=False):
"""Return file-like object for 'name'.
name is a string for the file name within the ZIP file, or a ZipInfo
mode should be 'r' to read a file already in the ZIP file, or 'w' to
write to a file newly added to the archive.
pwd is the password to decrypt files (only used for reading).
When writing, if the file size is not known in advance but may exceed
2 GiB, pass force_zip64 to use the ZIP64 format, which can handle large
files. If the size is known in advance, it is best to pass a ZipInfo
instance for name, with zinfo.file_size set.
if mode not in {"r", "w"}:
raise ValueError('open() requires mode "r" or "w"')
if pwd and not isinstance(pwd, bytes):
raise TypeError("pwd: expected bytes, got %s" % type(pwd).__name__)
if pwd and (mode == "w"):
raise ValueError("pwd is only supported for reading files")
if not self.fp:
raise ValueError(
"Attempt to use ZIP archive that was already closed")
# Make sure we have an info object
if isinstance(name, ZipInfo):
# 'name' is already an info object
zinfo = name
elif mode == 'w':
zinfo = ZipInfo(name)
zinfo.compress_type = self.compression
zinfo._compresslevel = self.compresslevel
# Get info object for name
zinfo = self.getinfo(name)
if mode == 'w':
return self._open_to_write(zinfo, force_zip64=force_zip64)
if self._writing:
raise ValueError("Can't read from the ZIP file while there "
"is an open writing handle on it. "
"Close the writing handle before trying to read.")
# Open for reading:
self._fileRefCnt += 1
zef_file = _SharedFile(self.fp, zinfo.header_offset,
self._fpclose, self._lock, lambda: self._writing)
# Skip the file header:
fheader =
if len(fheader) != sizeFileHeader:
raise BadZipFile("Truncated file header")
fheader = struct.unpack(structFileHeader, fheader)
if fheader[_FH_SIGNATURE] != stringFileHeader:
raise BadZipFile("Bad magic number for file header")
if zinfo.flag_bits & 0x20:
# Zip 2.7: compressed patched data
raise NotImplementedError("compressed patched data (flag bit 5)")
if zinfo.flag_bits & 0x40:
# strong encryption
raise NotImplementedError("strong encryption (flag bit 6)")
if fheader[_FH_GENERAL_PURPOSE_FLAG_BITS] & 0x800:
# UTF-8 filename
fname_str = fname.decode("utf-8")
fname_str = fname.decode("cp437")
if fname_str != zinfo.orig_filename:
raise BadZipFile(
'File name in directory %r and header %r differ.'
% (zinfo.orig_filename, fname))
# check for encrypted flag & handle password
is_encrypted = zinfo.flag_bits & 0x1
if is_encrypted:
if not pwd:
pwd = self.pwd
if not pwd:
raise RuntimeError("File %r is encrypted, password "
"required for extraction" % name)
pwd = None
return ZipExtFile(zef_file, mode, zinfo, pwd, True)
def _open_to_write(self, zinfo, force_zip64=False):
if force_zip64 and not self._allowZip64:
raise ValueError(
"force_zip64 is True, but allowZip64 was False when opening "
"the ZIP file."
if self._writing:
raise ValueError("Can't write to the ZIP file while there is "
"another write handle open on it. "
"Close the first handle before opening another.")
# Size and CRC are overwritten with correct data after processing the file
zinfo.compress_size = 0
zinfo.CRC = 0
zinfo.flag_bits = 0x00
if zinfo.compress_type == ZIP_LZMA:
# Compressed data includes an end-of-stream (EOS) marker
zinfo.flag_bits |= 0x02
if not self._seekable:
zinfo.flag_bits |= 0x08
if not zinfo.external_attr:
zinfo.external_attr = 0o600 << 16 # permissions: ?rw-------
# Compressed size can be larger than uncompressed size
zip64 = self._allowZip64 and \
(force_zip64 or zinfo.file_size * 1.05 > ZIP64_LIMIT)
if self._seekable:
zinfo.header_offset = self.fp.tell()
self._didModify = True
self._writing = True
return _ZipWriteFile(self, zinfo, zip64)
def extract(self, member, path=None, pwd=None):
"""Extract a member from the archive to the current working directory,
using its full name. Its file information is extracted as accurately
as possible. `member' may be a filename or a ZipInfo object. You can
specify a different directory using `path'.
if path is None:
path = os.getcwd()
path = os.fspath(path)
return self._extract_member(member, path, pwd)
def extractall(self, path=None, members=None, pwd=None):
"""Extract all members from the archive to the current working
directory. `path' specifies a different directory to extract to.
`members' is optional and must be a subset of the list returned
by namelist().
if members is None:
members = self.namelist()
if path is None:
path = os.getcwd()
path = os.fspath(path)
for zipinfo in members:
self._extract_member(zipinfo, path, pwd)
def _sanitize_windows_name(cls, arcname, pathsep):
"""Replace bad characters and remove trailing dots from parts."""
table = cls._windows_illegal_name_trans_table
if not table:
illegal = ':<>|"?*'
table = str.maketrans(illegal, '_' * len(illegal))
cls._windows_illegal_name_trans_table = table
arcname = arcname.translate(table)
# remove trailing dots
arcname = (x.rstrip('.') for x in arcname.split(pathsep))
# rejoin, removing empty parts.
arcname = pathsep.join(x for x in arcname if x)
return arcname
def _extract_member(self, member, targetpath, pwd):
"""Extract the ZipInfo object 'member' to a physical
file on the path targetpath.
if not isinstance(member, ZipInfo):
member = self.getinfo(member)
# build the destination pathname, replacing
# forward slashes to platform specific separators.
arcname = member.filename.replace('/', os.path.sep)
if os.path.altsep:
arcname = arcname.replace(os.path.altsep, os.path.sep)
# interpret absolute pathname as relative, remove drive letter or
# UNC path, redundant separators, "." and ".." components.
arcname = os.path.splitdrive(arcname)[1]
invalid_path_parts = ('', os.path.curdir, os.path.pardir)
arcname = os.path.sep.join(x for x in arcname.split(os.path.sep)
if x not in invalid_path_parts)
if os.path.sep == '\\':
# filter illegal characters on Windows
arcname = self._sanitize_windows_name(arcname, os.path.sep)
targetpath = os.path.join(targetpath, arcname)
targetpath = os.path.normpath(targetpath)
# Create all upper directories if necessary.
upperdirs = os.path.dirname(targetpath)
if upperdirs and not os.path.exists(upperdirs):
if member.is_dir():
if not os.path.isdir(targetpath):
return targetpath
with, pwd=pwd) as source, \
open(targetpath, "wb") as target:
shutil.copyfileobj(source, target)
return targetpath
def _writecheck(self, zinfo):
"""Check for errors before writing a file to the archive."""
if zinfo.filename in self.NameToInfo:
import warnings
warnings.warn('Duplicate name: %r' % zinfo.filename, stacklevel=3)
if self.mode not in ('w', 'x', 'a'):
raise ValueError("write() requires mode 'w', 'x', or 'a'")
if not self.fp:
raise ValueError(
"Attempt to write ZIP archive that was already closed")
if not self._allowZip64:
requires_zip64 = None
if len(self.filelist) >= ZIP_FILECOUNT_LIMIT:
requires_zip64 = "Files count"
elif zinfo.file_size > ZIP64_LIMIT:
requires_zip64 = "Filesize"
elif zinfo.header_offset > ZIP64_LIMIT:
requires_zip64 = "Zipfile size"
if requires_zip64:
raise LargeZipFile(requires_zip64 +
" would require ZIP64 extensions")
def write(self, filename, arcname=None,
compress_type=None, compresslevel=None):
"""Put the bytes from filename into the archive under the name
if not self.fp:
raise ValueError(
"Attempt to write to ZIP archive that was already closed")
if self._writing:
raise ValueError(
"Can't write to ZIP archive while an open writing handle exists"
zinfo = ZipInfo.from_file(filename, arcname,
if zinfo.is_dir():
zinfo.compress_size = 0
zinfo.CRC = 0
if compress_type is not None:
zinfo.compress_type = compress_type
zinfo.compress_type = self.compression
if compresslevel is not None:
zinfo._compresslevel = compresslevel
zinfo._compresslevel = self.compresslevel
if zinfo.is_dir():
with self._lock:
if self._seekable:
zinfo.header_offset = self.fp.tell() # Start of header bytes
if zinfo.compress_type == ZIP_LZMA:
# Compressed data includes an end-of-stream (EOS) marker
zinfo.flag_bits |= 0x02
self._didModify = True
self.NameToInfo[zinfo.filename] = zinfo
self.start_dir = self.fp.tell()
with open(filename, "rb") as src,, 'w') as dest:
shutil.copyfileobj(src, dest, 1024*8)
def writestr(self, zinfo_or_arcname, data,
compress_type=None, compresslevel=None):
"""Write a file into the archive. The contents is 'data', which
may be either a 'str' or a 'bytes' instance; if it is a 'str',
it is encoded as UTF-8 first.
'zinfo_or_arcname' is either a ZipInfo instance or
the name of the file in the archive."""
if isinstance(data, str):
data = data.encode("utf-8")
if not isinstance(zinfo_or_arcname, ZipInfo):
zinfo = ZipInfo(filename=zinfo_or_arcname,
zinfo.compress_type = self.compression
zinfo._compresslevel = self.compresslevel
if zinfo.filename[-1] == '/':
zinfo.external_attr = 0o40775 << 16 # drwxrwxr-x
zinfo.external_attr |= 0x10 # MS-DOS directory flag
zinfo.external_attr = 0o600 << 16 # ?rw-------
zinfo = zinfo_or_arcname
if not self.fp:
raise ValueError(
"Attempt to write to ZIP archive that was already closed")
if self._writing:
raise ValueError(
"Can't write to ZIP archive while an open writing handle exists."
if compress_type is not None:
zinfo.compress_type = compress_type
if compresslevel is not None:
zinfo._compresslevel = compresslevel
zinfo.file_size = len(data) # Uncompressed size
with self._lock:
with, mode='w') as dest:
def __del__(self):
"""Call the "close()" method in case the user forgot."""
def close(self):
"""Close the file, and for mode 'w', 'x' and 'a' write the ending
if self.fp is None:
if self._writing:
raise ValueError("Can't close the ZIP file while there is "
"an open writing handle on it. "
"Close the writing handle before closing the zip.")
if self.mode in ('w', 'x', 'a') and self._didModify: # write ending records
with self._lock:
if self._seekable:
fp = self.fp
self.fp = None
def _write_end_record(self):
for zinfo in self.filelist: # write central directory
dt = zinfo.date_time
dosdate = (dt[0] - 1980) << 9 | dt[1] << 5 | dt[2]
dostime = dt[3] << 11 | dt[4] << 5 | (dt[5] // 2)
extra = []
if zinfo.file_size > ZIP64_LIMIT \
or zinfo.compress_size > ZIP64_LIMIT:
file_size = 0xffffffff
compress_size = 0xffffffff
file_size = zinfo.file_size
compress_size = zinfo.compress_size
if zinfo.header_offset > ZIP64_LIMIT:
header_offset = 0xffffffff
header_offset = zinfo.header_offset
extra_data = zinfo.extra
min_version = 0
if extra:
# Append a ZIP64 field to the extra's
extra_data = _strip_extra(extra_data, (1,))
extra_data = struct.pack(
'<HH' + 'Q'*len(extra),
1, 8*len(extra), *extra) + extra_data
min_version = ZIP64_VERSION
if zinfo.compress_type == ZIP_BZIP2:
min_version = max(BZIP2_VERSION, min_version)
elif zinfo.compress_type == ZIP_LZMA:
min_version = max(LZMA_VERSION, min_version)
extract_version = max(min_version, zinfo.extract_version)
create_version = max(min_version, zinfo.create_version)
filename, flag_bits = zinfo._encodeFilenameFlags()
centdir = struct.pack(structCentralDir,
stringCentralDir, create_version,
zinfo.create_system, extract_version, zinfo.reserved,
flag_bits, zinfo.compress_type, dostime, dosdate,
zinfo.CRC, compress_size, file_size,
len(filename), len(extra_data), len(zinfo.comment),
0, zinfo.internal_attr, zinfo.external_attr,
pos2 = self.fp.tell()
# Write end-of-zip-archive record
centDirCount = len(self.filelist)
centDirSize = pos2 - self.start_dir
centDirOffset = self.start_dir
requires_zip64 = None
if centDirCount > ZIP_FILECOUNT_LIMIT:
requires_zip64 = "Files count"
elif centDirOffset > ZIP64_LIMIT:
requires_zip64 = "Central directory offset"
elif centDirSize > ZIP64_LIMIT:
requires_zip64 = "Central directory size"
if requires_zip64:
# Need to write the ZIP64 end-of-archive records
if not self._allowZip64:
raise LargeZipFile(requires_zip64 +
" would require ZIP64 extensions")
zip64endrec = struct.pack(
structEndArchive64, stringEndArchive64,
44, 45, 45, 0, 0, centDirCount, centDirCount,
centDirSize, centDirOffset)
zip64locrec = struct.pack(
stringEndArchive64Locator, 0, pos2, 1)
centDirCount = min(centDirCount, 0xFFFF)
centDirSize = min(centDirSize, 0xFFFFFFFF)
centDirOffset = min(centDirOffset, 0xFFFFFFFF)
endrec = struct.pack(structEndArchive, stringEndArchive,
0, 0, centDirCount, centDirCount,
centDirSize, centDirOffset, len(self._comment))
def _fpclose(self, fp):
assert self._fileRefCnt > 0
self._fileRefCnt -= 1
if not self._fileRefCnt and not self._filePassed:
class PyZipFile(ZipFile):
"""Class to create ZIP archives with Python library files and packages."""
def __init__(self, file, mode="r", compression=ZIP_STORED,
allowZip64=True, optimize=-1):
ZipFile.__init__(self, file, mode=mode, compression=compression,
self._optimize = optimize
def writepy(self, pathname, basename="", filterfunc=None):
"""Add all files from "pathname" to the ZIP archive.
If pathname is a package directory, search the directory and
all package subdirectories recursively for all *.py and enter
the modules into the archive. If pathname is a plain
directory, listdir *.py and enter all modules. Else, pathname
must be a Python *.py file and the module will be put into the
archive. Added modules are always module.pyc.
This method will compile the into module.pyc if
If filterfunc(pathname) is given, it is called with every argument.
When it is False, the file or directory is skipped.
pathname = os.fspath(pathname)
if filterfunc and not filterfunc(pathname):
if self.debug:
label = 'path' if os.path.isdir(pathname) else 'file'
print('%s %r skipped by filterfunc' % (label, pathname))
dir, name = os.path.split(pathname)
if os.path.isdir(pathname):
initname = os.path.join(pathname, "")
if os.path.isfile(initname):
# This is a package directory, add it
if basename:
basename = "%s/%s" % (basename, name)
basename = name
if self.debug:
print("Adding package in", pathname, "as", basename)
fname, arcname = self._get_codename(initname[0:-3], basename)
if self.debug:
print("Adding", arcname)
self.write(fname, arcname)
dirlist = sorted(os.listdir(pathname))
# Add all *.py files and package subdirectories
for filename in dirlist:
path = os.path.join(pathname, filename)
root, ext = os.path.splitext(filename)
if os.path.isdir(path):
if os.path.isfile(os.path.join(path, "")):
# This is a package directory, add it
self.writepy(path, basename,
filterfunc=filterfunc) # Recursive call
elif ext == ".py":
if filterfunc and not filterfunc(path):
if self.debug:
print('file %r skipped by filterfunc' % path)
fname, arcname = self._get_codename(path[0:-3],
if self.debug:
print("Adding", arcname)
self.write(fname, arcname)
# This is NOT a package directory, add its files at top level
if self.debug:
print("Adding files from directory", pathname)
for filename in sorted(os.listdir(pathname)):
path = os.path.join(pathname, filename)
root, ext = os.path.splitext(filename)
if ext == ".py":
if filterfunc and not filterfunc(path):
if self.debug:
print('file %r skipped by filterfunc' % path)
fname, arcname = self._get_codename(path[0:-3],
if self.debug:
print("Adding", arcname)
self.write(fname, arcname)
if pathname[-3:] != ".py":
raise RuntimeError(
'Files added with writepy() must end with ".py"')
fname, arcname = self._get_codename(pathname[0:-3], basename)
if self.debug:
print("Adding file", arcname)
self.write(fname, arcname)
def _get_codename(self, pathname, basename):
"""Return (filename, archivename) for the path.
Given a module name path, return the correct file path and
archive name, compiling if necessary. For example, given
/python/lib/string, return (/python/lib/string.pyc, string).
def _compile(file, optimize=-1):
import py_compile
if self.debug:
print("Compiling", file)
py_compile.compile(file, doraise=True, optimize=optimize)
except py_compile.PyCompileError as err:
return False
return True
file_py = pathname + ".py"
file_pyc = pathname + ".pyc"
pycache_opt0 = importlib.util.cache_from_source(file_py, optimization='')
pycache_opt1 = importlib.util.cache_from_source(file_py, optimization=1)
pycache_opt2 = importlib.util.cache_from_source(file_py, optimization=2)
if self._optimize == -1:
# legacy mode: use whatever file is present
if (os.path.isfile(file_pyc) and
os.stat(file_pyc).st_mtime >= os.stat(file_py).st_mtime):
# Use .pyc file.
arcname = fname = file_pyc
elif (os.path.isfile(pycache_opt0) and
os.stat(pycache_opt0).st_mtime >= os.stat(file_py).st_mtime):
# Use the __pycache__/*.pyc file, but write it to the legacy pyc
# file name in the archive.
fname = pycache_opt0
arcname = file_pyc
elif (os.path.isfile(pycache_opt1) and
os.stat(pycache_opt1).st_mtime >= os.stat(file_py).st_mtime):
# Use the __pycache__/*.pyc file, but write it to the legacy pyc
# file name in the archive.
fname = pycache_opt1
arcname = file_pyc
elif (os.path.isfile(pycache_opt2) and
os.stat(pycache_opt2).st_mtime >= os.stat(file_py).st_mtime):
# Use the __pycache__/*.pyc file, but write it to the legacy pyc
# file name in the archive.
fname = pycache_opt2
arcname = file_pyc
# Compile py into PEP 3147 pyc file.
if _compile(file_py):
if sys.flags.optimize == 0:
fname = pycache_opt0
elif sys.flags.optimize == 1:
fname = pycache_opt1
fname = pycache_opt2
arcname = file_pyc
fname = arcname = file_py
# new mode: use given optimization level
if self._optimize == 0:
fname = pycache_opt0
arcname = file_pyc
arcname = file_pyc
if self._optimize == 1:
fname = pycache_opt1
elif self._optimize == 2:
fname = pycache_opt2
msg = "invalid value for 'optimize': {!r}".format(self._optimize)
raise ValueError(msg)
if not (os.path.isfile(fname) and
os.stat(fname).st_mtime >= os.stat(file_py).st_mtime):
if not _compile(file_py, optimize=self._optimize):
fname = arcname = file_py
archivename = os.path.split(arcname)[1]
if basename:
archivename = "%s/%s" % (basename, archivename)
return (fname, archivename)
def _parents(path):
Given a path with elements separated by
posixpath.sep, generate all parents of that path.
>>> list(_parents('b/d'))
>>> list(_parents('/b/d/'))
>>> list(_parents('b/d/f/'))
['b/d', 'b']
>>> list(_parents('b'))
>>> list(_parents(''))
return itertools.islice(_ancestry(path), 1, None)
def _ancestry(path):
Given a path with elements separated by
posixpath.sep, generate all elements of that path
>>> list(_ancestry('b/d'))
['b/d', 'b']
>>> list(_ancestry('/b/d/'))
['/b/d', '/b']
>>> list(_ancestry('b/d/f/'))
['b/d/f', 'b/d', 'b']
>>> list(_ancestry('b'))
>>> list(_ancestry(''))
path = path.rstrip(posixpath.sep)
while path and path != posixpath.sep:
yield path
path, tail = posixpath.split(path)
_dedupe = dict.fromkeys
"""Deduplicate an iterable in original order"""
def _difference(minuend, subtrahend):
Return items in minuend not in subtrahend, retaining order
with O(1) lookup.
return itertools.filterfalse(set(subtrahend).__contains__, minuend)
class CompleteDirs(ZipFile):
A ZipFile subclass that ensures that implied directories
are always included in the namelist.
def _implied_dirs(names):
parents = itertools.chain.from_iterable(map(_parents, names))
as_dirs = (p + posixpath.sep for p in parents)
return _dedupe(_difference(as_dirs, names))
def namelist(self):
names = super(CompleteDirs, self).namelist()
return names + list(self._implied_dirs(names))
def _name_set(self):
return set(self.namelist())
def resolve_dir(self, name):
If the name represents a directory, return that name
as a directory (with the trailing slash).
names = self._name_set()
dirname = name + '/'
dir_match = name not in names and dirname in names
return dirname if dir_match else name
def make(cls, source):
Given a source (filename or zipfile), return an
appropriate CompleteDirs subclass.
if isinstance(source, CompleteDirs):
return source
if not isinstance(source, ZipFile):
return cls(source)
# Only allow for FastPath when supplied zipfile is read-only
if 'r' not in source.mode:
cls = CompleteDirs
res = cls.__new__(cls)
return res
class FastLookup(CompleteDirs):
ZipFile subclass to ensure implicit
dirs exist and are resolved rapidly.
def namelist(self):
with contextlib.suppress(AttributeError):
return self.__names
self.__names = super(FastLookup, self).namelist()
return self.__names
def _name_set(self):
with contextlib.suppress(AttributeError):
return self.__lookup
self.__lookup = super(FastLookup, self)._name_set()
return self.__lookup
class Path:
A pathlib-compatible interface for zip files.
Consider a zip file with this structure::
├── a.txt
└── b
├── c.txt
└── d
└── e.txt
>>> data = io.BytesIO()
>>> zf = ZipFile(data, 'w')
>>> zf.writestr('a.txt', 'content of a')
>>> zf.writestr('b/c.txt', 'content of c')
>>> zf.writestr('b/d/e.txt', 'content of e')
>>> zf.filename = ''
Path accepts the zipfile object itself or a filename
>>> root = Path(zf)
From there, several path operations are available.
Directory iteration (including the zip file itself):
>>> a, b = root.iterdir()
>>> a
Path('', 'a.txt')
>>> b
Path('', 'b/')
name property:
join with divide operator:
>>> c = b / 'c.txt'
>>> c
Path('', 'b/c.txt')
Read text:
>>> c.read_text()
'content of c'
>>> c.exists()
>>> (b / 'missing.txt').exists()
Coercion to string:
>>> str(c)
__repr = "{self.__class__.__name__}({self.root.filename!r}, {!r})"
def __init__(self, root, at=""):
self.root = FastLookup.make(root) = at
def open(self, mode='r', *args, **kwargs):
Open this entry as text or binary following the semantics
of ```` by passing arguments through
to io.TextIOWrapper().
pwd = kwargs.pop('pwd', None)
zip_mode = mode[0]
stream =, zip_mode, pwd=pwd)
if 'b' in mode:
if args or kwargs:
raise ValueError("encoding args invalid for binary operation")
return stream
return io.TextIOWrapper(stream, *args, **kwargs)
def name(self):
return posixpath.basename("/"))
def read_text(self, *args, **kwargs):
with'r', *args, **kwargs) as strm:
def read_bytes(self):
with'rb') as strm:
def _is_child(self, path):
return posixpath.dirname("/")) =="/")
def _next(self, at):
return Path(self.root, at)
def is_dir(self):
return not or"/")
def is_file(self):
return not self.is_dir()
def exists(self):
return in self.root._name_set()
def iterdir(self):
if not self.is_dir():
raise ValueError("Can't listdir a file")
subs = map(self._next, self.root.namelist())
return filter(self._is_child, subs)
def __str__(self):
return posixpath.join(self.root.filename,
def __repr__(self):
return self.__repr.format(self=self)
def joinpath(self, add):
next = posixpath.join(, add)
return self._next(self.root.resolve_dir(next))
__truediv__ = joinpath
def parent(self):
parent_at = posixpath.dirname('/'))
if parent_at:
parent_at += '/'
return self._next(parent_at)
def main(args=None):
import argparse
description = 'A simple command-line interface for zipfile module.'
parser = argparse.ArgumentParser(description=description)
group = parser.add_mutually_exclusive_group(required=True)
group.add_argument('-l', '--list', metavar='<zipfile>',
help='Show listing of a zipfile')
group.add_argument('-e', '--extract', nargs=2,
metavar=('<zipfile>', '<output_dir>'),
help='Extract zipfile into target dir')
group.add_argument('-c', '--create', nargs='+',
metavar=('<name>', '<file>'),
help='Create zipfile from sources')
group.add_argument('-t', '--test', metavar='<zipfile>',
help='Test if a zipfile is valid')
args = parser.parse_args(args)
if args.test is not None:
src = args.test
with ZipFile(src, 'r') as zf:
badfile = zf.testzip()
if badfile:
print("The following enclosed file is corrupted: {!r}".format(badfile))
print("Done testing")
elif args.list is not None:
src = args.list
with ZipFile(src, 'r') as zf:
elif args.extract is not None:
src, curdir = args.extract
with ZipFile(src, 'r') as zf:
elif args.create is not None:
zip_name = args.create.pop(0)
files = args.create
def addToZip(zf, path, zippath):
if os.path.isfile(path):
zf.write(path, zippath, ZIP_DEFLATED)
elif os.path.isdir(path):
if zippath:
zf.write(path, zippath)
for nm in sorted(os.listdir(path)):
os.path.join(path, nm), os.path.join(zippath, nm))
# else: ignore
with ZipFile(zip_name, 'w') as zf:
for path in files:
zippath = os.path.basename(path)
if not zippath:
zippath = os.path.basename(os.path.dirname(path))
if zippath in ('', os.curdir, os.pardir):
zippath = ''
addToZip(zf, path, zippath)
if __name__ == "__main__":
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