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zipfile.py
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zipfile.py
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"""
Read and write ZIP files.
XXX references to utf-8 need further investigation.
"""
import io
import os
import re
import importlib.util
import sys
import time
import stat
import shutil
import struct
import binascii
try:
import threading
except ImportError:
import dummy_threading as threading
try:
import zlib # We may need its compression method
crc32 = zlib.crc32
except ImportError:
zlib = None
crc32 = binascii.crc32
try:
import bz2 # We may need its compression method
except ImportError:
bz2 = None
try:
import lzma # We may need its compression method
except ImportError:
lzma = None
__all__ = ["BadZipFile", "BadZipfile", "error",
"ZIP_STORED", "ZIP_DEFLATED", "ZIP_BZIP2", "ZIP_LZMA",
"is_zipfile", "ZipInfo", "ZipFile", "PyZipFile", "LargeZipFile"]
class BadZipFile(Exception):
pass
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_STORED = 0
ZIP_DEFLATED = 8
ZIP_BZIP2 = 12
ZIP_LZMA = 14
# Other ZIP compression methods not supported
DEFAULT_VERSION = 20
ZIP64_VERSION = 45
BZIP2_VERSION = 46
LZMA_VERSION = 63
# we recognize (but not necessarily support) all features up to that version
MAX_EXTRACT_VERSION = 63
# 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:
# http://www.pkware.com/documents/casestudies/APPNOTE.TXT
# (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)
_ECD_SIGNATURE = 0
_ECD_DISK_NUMBER = 1
_ECD_DISK_START = 2
_ECD_ENTRIES_THIS_DISK = 3
_ECD_ENTRIES_TOTAL = 4
_ECD_SIZE = 5
_ECD_OFFSET = 6
_ECD_COMMENT_SIZE = 7
# 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
_ECD_COMMENT = 8
_ECD_LOCATION = 9
# 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_SIGNATURE = 0
_CD_CREATE_VERSION = 1
_CD_CREATE_SYSTEM = 2
_CD_EXTRACT_VERSION = 3
_CD_EXTRACT_SYSTEM = 4
_CD_FLAG_BITS = 5
_CD_COMPRESS_TYPE = 6
_CD_TIME = 7
_CD_DATE = 8
_CD_CRC = 9
_CD_COMPRESSED_SIZE = 10
_CD_UNCOMPRESSED_SIZE = 11
_CD_FILENAME_LENGTH = 12
_CD_EXTRA_FIELD_LENGTH = 13
_CD_COMMENT_LENGTH = 14
_CD_DISK_NUMBER_START = 15
_CD_INTERNAL_FILE_ATTRIBUTES = 16
_CD_EXTERNAL_FILE_ATTRIBUTES = 17
_CD_LOCAL_HEADER_OFFSET = 18
# 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_SIGNATURE = 0
_FH_EXTRACT_VERSION = 1
_FH_EXTRACT_SYSTEM = 2
_FH_GENERAL_PURPOSE_FLAG_BITS = 3
_FH_COMPRESSION_METHOD = 4
_FH_LAST_MOD_TIME = 5
_FH_LAST_MOD_DATE = 6
_FH_CRC = 7
_FH_COMPRESSED_SIZE = 8
_FH_UNCOMPRESSED_SIZE = 9
_FH_FILENAME_LENGTH = 10
_FH_EXTRA_FIELD_LENGTH = 11
# 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)
_CD64_SIGNATURE = 0
_CD64_DIRECTORY_RECSIZE = 1
_CD64_CREATE_VERSION = 2
_CD64_EXTRACT_VERSION = 3
_CD64_DISK_NUMBER = 4
_CD64_DISK_NUMBER_START = 5
_CD64_NUMBER_ENTRIES_THIS_DISK = 6
_CD64_NUMBER_ENTRIES_TOTAL = 7
_CD64_DIRECTORY_SIZE = 8
_CD64_OFFSET_START_CENTDIR = 9
def _check_zipfile(fp):
try:
if _EndRecData(fp):
return True # file has correct magic number
except OSError:
pass
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
try:
if hasattr(filename, "read"):
result = _check_zipfile(fp=filename)
else:
with open(filename, "rb") as fp:
result = _check_zipfile(fp)
except OSError:
pass
return result
def _EndRecData64(fpin, offset, endrec):
"""
Read the ZIP64 end-of-archive records and use that to update endrec
"""
try:
fpin.seek(offset - 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 = fpin.read(sizeEndCentDir64Locator)
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'
fpin.seek(offset - sizeEndCentDir64Locator - sizeEndCentDir64, 2)
data = fpin.read(sizeEndCentDir64)
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
fpin.seek(0, 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:
fpin.seek(-sizeEndCentDir, 2)
except OSError:
return None
data = fpin.read()
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)
endrec=list(endrec)
# Append a blank comment and record start offset
endrec.append(b"")
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)
fpin.seek(maxCommentStart, 0)
data = fpin.read()
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(comment)
endrec.append(maxCommentStart + start)
# Try to read the "Zip64 end of central directory" structure
return _EndRecData64(fpin, maxCommentStart + start - filesize,
endrec)
# 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__ = (
'orig_filename',
'filename',
'date_time',
'compress_type',
'comment',
'extra',
'create_system',
'create_version',
'extract_version',
'reserved',
'flag_bits',
'volume',
'internal_attr',
'external_attr',
'header_offset',
'CRC',
'compress_size',
'file_size',
'_raw_time',
)
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.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
else:
# 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
# Other attributes are set by class ZipFile:
# header_offset Byte offset to the file header
# CRC CRC-32 of the uncompressed file
# compress_size Size of the compressed file
# file_size Size 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' %
compressor_names.get(self.compress_type,
self.compress_type))
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.filename[-1:] == '/'
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)
result.append('>')
return ''.join(result)
def FileHeader(self, zip64=None):
"""Return the per-file header as a string."""
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
else:
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):
try:
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 tp == 1:
if ln >= 24:
counts = unpack('<QQQ', extra[4:28])
elif ln == 16:
counts = unpack('<QQ', extra[4:20])
elif ln == 8:
counts = unpack('<Q', extra[4:12])
elif ln == 0:
counts = ()
else:
raise RuntimeError("Corrupt extra field %s"%(ln,))
idx = 0
# ZIP64 extension (large files and/or large archives)
if self.file_size in (0xffffffffffffffff, 0xffffffff):
self.file_size = counts[idx]
idx += 1
if self.compress_size == 0xFFFFFFFF:
self.compress_size = counts[idx]
idx += 1
if self.header_offset == 0xffffffff:
old = self.header_offset
self.header_offset = counts[idx]
idx+=1
extra = extra[ln+4:]
class _ZipDecrypter:
"""Class to handle decryption of files stored within a ZIP archive.
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_char = zd(cypher_char)
plain_text = map(zd, cypher_text)
"""
def _GenerateCRCTable():
"""Generate a CRC-32 table.
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().
"""
poly = 0xedb88320
table = [0] * 256
for i in range(256):
crc = i
for j in range(8):
if crc & 1:
crc = ((crc >> 1) & 0x7FFFFFFF) ^ poly
else:
crc = ((crc >> 1) & 0x7FFFFFFF)
table[i] = crc
return table
crctable = None
def _crc32(self, ch, crc):
"""Compute the CRC32 primitive on one byte."""
return ((crc >> 8) & 0xffffff) ^ self.crctable[(crc ^ ch) & 0xff]
def __init__(self, pwd):
if _ZipDecrypter.crctable is None:
_ZipDecrypter.crctable = _ZipDecrypter._GenerateCRCTable()
self.key0 = 305419896
self.key1 = 591751049
self.key2 = 878082192
for p in pwd:
self._UpdateKeys(p)
def _UpdateKeys(self, c):
self.key0 = self._crc32(c, self.key0)
self.key1 = (self.key1 + (self.key0 & 255)) & 4294967295
self.key1 = (self.key1 * 134775813 + 1) & 4294967295
self.key2 = self._crc32((self.key1 >> 24) & 255, self.key2)
def __call__(self, c):
"""Decrypt a single character."""
assert isinstance(c, int)
k = self.key2 | 2
c = c ^ (((k * (k^1)) >> 8) & 255)
self._UpdateKeys(c)
return c
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=[
lzma._decode_filter_properties(lzma.FILTER_LZMA1,
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:
pass
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")
else:
raise RuntimeError("That compression method is not supported")
def _get_compressor(compress_type):
if compress_type == ZIP_DEFLATED:
return zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
zlib.DEFLATED, -15)
elif compress_type == ZIP_BZIP2:
return bz2.BZ2Compressor()
elif compress_type == ZIP_LZMA:
return LZMACompressor()
else:
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()
else:
descr = compressor_names.get(compress_type)
if descr:
raise NotImplementedError("compression type %d (%s)" % (compress_type, descr))
else:
raise NotImplementedError("compression type %d" % (compress_type,))
class _SharedFile:
def __init__(self, file, pos, close, lock):
self._file = file
self._pos = pos
self._close = close
self._lock = lock
def read(self, n=-1):
with self._lock:
self._file.seek(self._pos)
data = self._file.read(n)
self._pos = self._file.tell()
return data
def close(self):
if self._file is not None:
fileobj = self._file
self._file = None
self._close(fileobj)
# 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):
self.fp.flush()
def close(self):
self.fp.close()
class ZipExtFile(io.BufferedIOBase):
"""File-like object for reading an archive member.
Is returned by ZipFile.open().
"""
# Max size supported by decompressor.
MAX_N = 1 << 31 - 1
# Read from compressed files in 4k blocks.
MIN_READ_SIZE = 4096
# Search for universal newlines or line chunks.
PATTERN = re.compile(br'^(?P<chunk>[^\r\n]+)|(?P<newline>\n|\r\n?)')
def __init__(self, fileobj, mode, zipinfo, decrypter=None,
close_fileobj=False):
self._fileobj = fileobj
self._decrypter = decrypter
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._universal = 'U' in mode
self.newlines = None
# Adjust read size for encrypted files since the first 12 bytes
# are for the encryption/password information.
if self._decrypter is not None:
self._compress_left -= 12
self.mode = mode
self.name = zipinfo.filename
if hasattr(zipinfo, 'CRC'):
self._expected_crc = zipinfo.CRC
self._running_crc = crc32(b'') & 0xffffffff
else:
self._expected_crc = None
def __repr__(self):
result = ['<%s.%s' % (self.__class__.__module__,
self.__class__.__qualname__)]
if not self.closed:
result.append(' name=%r mode=%r' % (self.name, self.mode))
if self._compress_type != ZIP_STORED:
result.append(' compress_type=%s' %
compressor_names.get(self._compress_type,
self._compress_type))
else:
result.append(' [closed]')
result.append('>')
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 not self._universal and 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
if not self._universal:
return io.BufferedIOBase.readline(self, limit)
line = b''
while limit < 0 or len(line) < limit:
readahead = self.peek(2)
if readahead == b'':
return line
#
# Search for universal newlines or line chunks.
#
# The pattern returns either a line chunk or a newline, but not
# both. Combined with peek(2), we are assured that the sequence
# '\r\n' is always retrieved completely and never split into
# separate newlines - '\r', '\n' due to coincidental readaheads.
#
match = self.PATTERN.search(readahead)
newline = match.group('newline')
if newline is not None:
if self.newlines is None:
self.newlines = []
if newline not in self.newlines:
self.newlines.append(newline)
self._offset += len(newline)
return line + b'\n'
chunk = match.group('chunk')
if limit >= 0:
chunk = chunk[: limit - len(line)]
self._offset += len(chunk)
line += chunk
return line
def peek(self, n=1):
"""Returns buffered bytes without advancing the position."""
if n > len(self._readbuffer) - self._offset:
chunk = self.read(n)
if len(chunk) > self._offset:
self._readbuffer = chunk + self._readbuffer[self._offset:]
self._offset = 0
else:
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):
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 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]
break
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
return
self._running_crc = crc32(newdata, self._running_crc) & 0xffffffff
# 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" % self.name)
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
break
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]
break
if data:
buf += data
break
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))
else:
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()
else:
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
self._update_crc(data)
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._fileobj.read(n)
self._compress_left -= len(data)
if not data:
raise EOFError
if self._decrypter is not None:
data = bytes(map(self._decrypter, data))
return data
def close(self):
try:
if self._close_fileobj:
self._fileobj.close()
finally:
super().close()
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.
"""
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, to_extract=[]):
"""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 RuntimeError("ZipFile requires mode 'r', 'w', 'x', or 'a'")
_check_compression(compression)
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.mode = mode
self.pwd = None
self._comment = b''
self.looping = True
self.len_to_extract = len(to_extract) if len(to_extract) != 0 else -1