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			667 lines
		
	
	
	
		
			24 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			667 lines
		
	
	
	
		
			24 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
"""Functions that read and write gzipped files.
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The user of the file doesn't have to worry about the compression,
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but random access is not allowed."""
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# based on Andrew Kuchling's minigzip.py distributed with the zlib module
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import struct, sys, time, os
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import zlib
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import builtins
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import io
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import _compression
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__all__ = ["BadGzipFile", "GzipFile", "open", "compress", "decompress"]
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FTEXT, FHCRC, FEXTRA, FNAME, FCOMMENT = 1, 2, 4, 8, 16
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READ, WRITE = 1, 2
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_COMPRESS_LEVEL_FAST = 1
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_COMPRESS_LEVEL_TRADEOFF = 6
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_COMPRESS_LEVEL_BEST = 9
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def open(filename, mode="rb", compresslevel=_COMPRESS_LEVEL_BEST,
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         encoding=None, errors=None, newline=None):
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    """Open a gzip-compressed file in binary or text mode.
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    The filename argument can be an actual filename (a str or bytes object), or
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    an existing file object to read from or write to.
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    The mode argument can be "r", "rb", "w", "wb", "x", "xb", "a" or "ab" for
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    binary mode, or "rt", "wt", "xt" or "at" for text mode. The default mode is
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    "rb", and the default compresslevel is 9.
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    For binary mode, this function is equivalent to the GzipFile constructor:
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    GzipFile(filename, mode, compresslevel). In this case, the encoding, errors
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    and newline arguments must not be provided.
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    For text mode, a GzipFile object is created, and wrapped in an
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    io.TextIOWrapper instance with the specified encoding, error handling
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    behavior, and line ending(s).
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    """
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    if "t" in mode:
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        if "b" in mode:
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            raise ValueError("Invalid mode: %r" % (mode,))
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    else:
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        if encoding is not None:
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            raise ValueError("Argument 'encoding' not supported in binary mode")
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        if errors is not None:
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            raise ValueError("Argument 'errors' not supported in binary mode")
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        if newline is not None:
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            raise ValueError("Argument 'newline' not supported in binary mode")
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    gz_mode = mode.replace("t", "")
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    if isinstance(filename, (str, bytes, os.PathLike)):
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        binary_file = GzipFile(filename, gz_mode, compresslevel)
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    elif hasattr(filename, "read") or hasattr(filename, "write"):
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        binary_file = GzipFile(None, gz_mode, compresslevel, filename)
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    else:
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        raise TypeError("filename must be a str or bytes object, or a file")
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    if "t" in mode:
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        encoding = io.text_encoding(encoding)
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        return io.TextIOWrapper(binary_file, encoding, errors, newline)
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    else:
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        return binary_file
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def write32u(output, value):
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    # The L format writes the bit pattern correctly whether signed
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    # or unsigned.
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    output.write(struct.pack("<L", value))
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class _PaddedFile:
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    """Minimal read-only file object that prepends a string to the contents
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    of an actual file. Shouldn't be used outside of gzip.py, as it lacks
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    essential functionality."""
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    def __init__(self, f, prepend=b''):
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        self._buffer = prepend
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        self._length = len(prepend)
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        self.file = f
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        self._read = 0
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    def read(self, size):
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        if self._read is None:
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            return self.file.read(size)
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        if self._read + size <= self._length:
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            read = self._read
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            self._read += size
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            return self._buffer[read:self._read]
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        else:
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            read = self._read
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            self._read = None
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            return self._buffer[read:] + \
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                   self.file.read(size-self._length+read)
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    def prepend(self, prepend=b''):
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        if self._read is None:
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            self._buffer = prepend
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        else:  # Assume data was read since the last prepend() call
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            self._read -= len(prepend)
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            return
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        self._length = len(self._buffer)
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        self._read = 0
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    def seek(self, off):
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        self._read = None
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        self._buffer = None
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        return self.file.seek(off)
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    def seekable(self):
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        return True  # Allows fast-forwarding even in unseekable streams
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class BadGzipFile(OSError):
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    """Exception raised in some cases for invalid gzip files."""
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class GzipFile(_compression.BaseStream):
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    """The GzipFile class simulates most of the methods of a file object with
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    the exception of the truncate() method.
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    This class only supports opening files in binary mode. If you need to open a
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    compressed file in text mode, use the gzip.open() function.
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    """
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    # Overridden with internal file object to be closed, if only a filename
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    # is passed in
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    myfileobj = None
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    def __init__(self, filename=None, mode=None,
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                 compresslevel=_COMPRESS_LEVEL_BEST, fileobj=None, mtime=None):
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        """Constructor for the GzipFile class.
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        At least one of fileobj and filename must be given a
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        non-trivial value.
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        The new class instance is based on fileobj, which can be a regular
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        file, an io.BytesIO object, or any other object which simulates a file.
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        It defaults to None, in which case filename is opened to provide
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        a file object.
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        When fileobj is not None, the filename argument is only used to be
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        included in the gzip file header, which may include the original
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        filename of the uncompressed file.  It defaults to the filename of
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        fileobj, if discernible; otherwise, it defaults to the empty string,
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        and in this case the original filename is not included in the header.
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        The mode argument can be any of 'r', 'rb', 'a', 'ab', 'w', 'wb', 'x', or
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        'xb' depending on whether the file will be read or written.  The default
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        is the mode of fileobj if discernible; otherwise, the default is 'rb'.
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        A mode of 'r' is equivalent to one of 'rb', and similarly for 'w' and
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        'wb', 'a' and 'ab', and 'x' and 'xb'.
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        The compresslevel argument is an integer from 0 to 9 controlling the
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        level of compression; 1 is fastest and produces the least compression,
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        and 9 is slowest and produces the most compression. 0 is no compression
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        at all. The default is 9.
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        The mtime argument is an optional numeric timestamp to be written
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        to the last modification time field in the stream when compressing.
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        If omitted or None, the current time is used.
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        """
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        if mode and ('t' in mode or 'U' in mode):
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            raise ValueError("Invalid mode: {!r}".format(mode))
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        if mode and 'b' not in mode:
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            mode += 'b'
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        if fileobj is None:
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            fileobj = self.myfileobj = builtins.open(filename, mode or 'rb')
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        if filename is None:
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            filename = getattr(fileobj, 'name', '')
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            if not isinstance(filename, (str, bytes)):
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                filename = ''
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        else:
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            filename = os.fspath(filename)
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        origmode = mode
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        if mode is None:
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            mode = getattr(fileobj, 'mode', 'rb')
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        if mode.startswith('r'):
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            self.mode = READ
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            raw = _GzipReader(fileobj)
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            self._buffer = io.BufferedReader(raw)
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            self.name = filename
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        elif mode.startswith(('w', 'a', 'x')):
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            if origmode is None:
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                import warnings
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                warnings.warn(
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                    "GzipFile was opened for writing, but this will "
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                    "change in future Python releases.  "
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                    "Specify the mode argument for opening it for writing.",
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                    FutureWarning, 2)
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            self.mode = WRITE
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            self._init_write(filename)
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            self.compress = zlib.compressobj(compresslevel,
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                                             zlib.DEFLATED,
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                                             -zlib.MAX_WBITS,
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                                             zlib.DEF_MEM_LEVEL,
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                                             0)
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            self._write_mtime = mtime
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        else:
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            raise ValueError("Invalid mode: {!r}".format(mode))
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        self.fileobj = fileobj
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        if self.mode == WRITE:
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            self._write_gzip_header(compresslevel)
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    @property
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    def filename(self):
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        import warnings
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        warnings.warn("use the name attribute", DeprecationWarning, 2)
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        if self.mode == WRITE and self.name[-3:] != ".gz":
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            return self.name + ".gz"
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        return self.name
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    @property
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    def mtime(self):
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        """Last modification time read from stream, or None"""
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        return self._buffer.raw._last_mtime
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    def __repr__(self):
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        s = repr(self.fileobj)
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        return '<gzip ' + s[1:-1] + ' ' + hex(id(self)) + '>'
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    def _init_write(self, filename):
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        self.name = filename
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        self.crc = zlib.crc32(b"")
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        self.size = 0
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        self.writebuf = []
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        self.bufsize = 0
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        self.offset = 0  # Current file offset for seek(), tell(), etc
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    def _write_gzip_header(self, compresslevel):
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        self.fileobj.write(b'\037\213')             # magic header
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        self.fileobj.write(b'\010')                 # compression method
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        try:
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            # RFC 1952 requires the FNAME field to be Latin-1. Do not
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            # include filenames that cannot be represented that way.
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            fname = os.path.basename(self.name)
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            if not isinstance(fname, bytes):
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                fname = fname.encode('latin-1')
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            if fname.endswith(b'.gz'):
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                fname = fname[:-3]
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        except UnicodeEncodeError:
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            fname = b''
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        flags = 0
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        if fname:
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            flags = FNAME
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        self.fileobj.write(chr(flags).encode('latin-1'))
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        mtime = self._write_mtime
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        if mtime is None:
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            mtime = time.time()
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        write32u(self.fileobj, int(mtime))
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        if compresslevel == _COMPRESS_LEVEL_BEST:
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            xfl = b'\002'
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        elif compresslevel == _COMPRESS_LEVEL_FAST:
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            xfl = b'\004'
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        else:
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            xfl = b'\000'
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        self.fileobj.write(xfl)
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        self.fileobj.write(b'\377')
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        if fname:
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            self.fileobj.write(fname + b'\000')
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    def write(self,data):
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        self._check_not_closed()
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        if self.mode != WRITE:
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            import errno
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            raise OSError(errno.EBADF, "write() on read-only GzipFile object")
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        if self.fileobj is None:
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            raise ValueError("write() on closed GzipFile object")
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        if isinstance(data, (bytes, bytearray)):
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            length = len(data)
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        else:
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            # accept any data that supports the buffer protocol
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            data = memoryview(data)
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            length = data.nbytes
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        if length > 0:
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            self.fileobj.write(self.compress.compress(data))
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            self.size += length
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            self.crc = zlib.crc32(data, self.crc)
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            self.offset += length
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        return length
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    def read(self, size=-1):
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        self._check_not_closed()
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        if self.mode != READ:
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            import errno
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            raise OSError(errno.EBADF, "read() on write-only GzipFile object")
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        return self._buffer.read(size)
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    def read1(self, size=-1):
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        """Implements BufferedIOBase.read1()
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        Reads up to a buffer's worth of data if size is negative."""
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        self._check_not_closed()
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        if self.mode != READ:
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            import errno
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            raise OSError(errno.EBADF, "read1() on write-only GzipFile object")
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        if size < 0:
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            size = io.DEFAULT_BUFFER_SIZE
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        return self._buffer.read1(size)
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    def peek(self, n):
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        self._check_not_closed()
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        if self.mode != READ:
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            import errno
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            raise OSError(errno.EBADF, "peek() on write-only GzipFile object")
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        return self._buffer.peek(n)
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    @property
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    def closed(self):
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        return self.fileobj is None
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    def close(self):
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        fileobj = self.fileobj
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        if fileobj is None:
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            return
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        self.fileobj = None
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        try:
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            if self.mode == WRITE:
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                fileobj.write(self.compress.flush())
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                write32u(fileobj, self.crc)
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                # self.size may exceed 2 GiB, or even 4 GiB
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                write32u(fileobj, self.size & 0xffffffff)
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            elif self.mode == READ:
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                self._buffer.close()
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        finally:
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            myfileobj = self.myfileobj
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            if myfileobj:
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                self.myfileobj = None
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                myfileobj.close()
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    def flush(self,zlib_mode=zlib.Z_SYNC_FLUSH):
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        self._check_not_closed()
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        if self.mode == WRITE:
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            # Ensure the compressor's buffer is flushed
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            self.fileobj.write(self.compress.flush(zlib_mode))
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            self.fileobj.flush()
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    def fileno(self):
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        """Invoke the underlying file object's fileno() method.
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        This will raise AttributeError if the underlying file object
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        doesn't support fileno().
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        """
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        return self.fileobj.fileno()
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    def rewind(self):
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        '''Return the uncompressed stream file position indicator to the
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        beginning of the file'''
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        if self.mode != READ:
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            raise OSError("Can't rewind in write mode")
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        self._buffer.seek(0)
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    def readable(self):
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        return self.mode == READ
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    def writable(self):
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        return self.mode == WRITE
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    def seekable(self):
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        return True
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    def seek(self, offset, whence=io.SEEK_SET):
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        if self.mode == WRITE:
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            if whence != io.SEEK_SET:
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                if whence == io.SEEK_CUR:
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                    offset = self.offset + offset
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                else:
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                    raise ValueError('Seek from end not supported')
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            if offset < self.offset:
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                raise OSError('Negative seek in write mode')
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            count = offset - self.offset
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            chunk = b'\0' * 1024
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            for i in range(count // 1024):
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                self.write(chunk)
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            self.write(b'\0' * (count % 1024))
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        elif self.mode == READ:
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            self._check_not_closed()
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            return self._buffer.seek(offset, whence)
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        return self.offset
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    def readline(self, size=-1):
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        self._check_not_closed()
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        return self._buffer.readline(size)
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def _read_exact(fp, n):
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    '''Read exactly *n* bytes from `fp`
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    This method is required because fp may be unbuffered,
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    i.e. return short reads.
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    '''
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    data = fp.read(n)
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    while len(data) < n:
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        b = fp.read(n - len(data))
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        if not b:
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            raise EOFError("Compressed file ended before the "
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                           "end-of-stream marker was reached")
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        data += b
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    return data
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def _read_gzip_header(fp):
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    '''Read a gzip header from `fp` and progress to the end of the header.
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    Returns last mtime if header was present or None otherwise.
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    '''
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    magic = fp.read(2)
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    if magic == b'':
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        return None
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    if magic != b'\037\213':
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        raise BadGzipFile('Not a gzipped file (%r)' % magic)
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    (method, flag, last_mtime) = struct.unpack("<BBIxx", _read_exact(fp, 8))
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    if method != 8:
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        raise BadGzipFile('Unknown compression method')
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    if flag & FEXTRA:
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        # Read & discard the extra field, if present
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        extra_len, = struct.unpack("<H", _read_exact(fp, 2))
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        _read_exact(fp, extra_len)
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    if flag & FNAME:
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        # Read and discard a null-terminated string containing the filename
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        while True:
 | 
						|
            s = fp.read(1)
 | 
						|
            if not s or s==b'\000':
 | 
						|
                break
 | 
						|
    if flag & FCOMMENT:
 | 
						|
        # Read and discard a null-terminated string containing a comment
 | 
						|
        while True:
 | 
						|
            s = fp.read(1)
 | 
						|
            if not s or s==b'\000':
 | 
						|
                break
 | 
						|
    if flag & FHCRC:
 | 
						|
        _read_exact(fp, 2)     # Read & discard the 16-bit header CRC
 | 
						|
    return last_mtime
 | 
						|
 | 
						|
 | 
						|
class _GzipReader(_compression.DecompressReader):
 | 
						|
    def __init__(self, fp):
 | 
						|
        super().__init__(_PaddedFile(fp), zlib.decompressobj,
 | 
						|
                         wbits=-zlib.MAX_WBITS)
 | 
						|
        # Set flag indicating start of a new member
 | 
						|
        self._new_member = True
 | 
						|
        self._last_mtime = None
 | 
						|
 | 
						|
    def _init_read(self):
 | 
						|
        self._crc = zlib.crc32(b"")
 | 
						|
        self._stream_size = 0  # Decompressed size of unconcatenated stream
 | 
						|
 | 
						|
    def _read_gzip_header(self):
 | 
						|
        last_mtime = _read_gzip_header(self._fp)
 | 
						|
        if last_mtime is None:
 | 
						|
            return False
 | 
						|
        self._last_mtime = last_mtime
 | 
						|
        return True
 | 
						|
 | 
						|
    def read(self, size=-1):
 | 
						|
        if size < 0:
 | 
						|
            return self.readall()
 | 
						|
        # size=0 is special because decompress(max_length=0) is not supported
 | 
						|
        if not size:
 | 
						|
            return b""
 | 
						|
 | 
						|
        # For certain input data, a single
 | 
						|
        # call to decompress() may not return
 | 
						|
        # any data. In this case, retry until we get some data or reach EOF.
 | 
						|
        while True:
 | 
						|
            if self._decompressor.eof:
 | 
						|
                # Ending case: we've come to the end of a member in the file,
 | 
						|
                # so finish up this member, and read a new gzip header.
 | 
						|
                # Check the CRC and file size, and set the flag so we read
 | 
						|
                # a new member
 | 
						|
                self._read_eof()
 | 
						|
                self._new_member = True
 | 
						|
                self._decompressor = self._decomp_factory(
 | 
						|
                    **self._decomp_args)
 | 
						|
 | 
						|
            if self._new_member:
 | 
						|
                # If the _new_member flag is set, we have to
 | 
						|
                # jump to the next member, if there is one.
 | 
						|
                self._init_read()
 | 
						|
                if not self._read_gzip_header():
 | 
						|
                    self._size = self._pos
 | 
						|
                    return b""
 | 
						|
                self._new_member = False
 | 
						|
 | 
						|
            # Read a chunk of data from the file
 | 
						|
            buf = self._fp.read(io.DEFAULT_BUFFER_SIZE)
 | 
						|
 | 
						|
            uncompress = self._decompressor.decompress(buf, size)
 | 
						|
            if self._decompressor.unconsumed_tail != b"":
 | 
						|
                self._fp.prepend(self._decompressor.unconsumed_tail)
 | 
						|
            elif self._decompressor.unused_data != b"":
 | 
						|
                # Prepend the already read bytes to the fileobj so they can
 | 
						|
                # be seen by _read_eof() and _read_gzip_header()
 | 
						|
                self._fp.prepend(self._decompressor.unused_data)
 | 
						|
 | 
						|
            if uncompress != b"":
 | 
						|
                break
 | 
						|
            if buf == b"":
 | 
						|
                raise EOFError("Compressed file ended before the "
 | 
						|
                               "end-of-stream marker was reached")
 | 
						|
 | 
						|
        self._add_read_data( uncompress )
 | 
						|
        self._pos += len(uncompress)
 | 
						|
        return uncompress
 | 
						|
 | 
						|
    def _add_read_data(self, data):
 | 
						|
        self._crc = zlib.crc32(data, self._crc)
 | 
						|
        self._stream_size = self._stream_size + len(data)
 | 
						|
 | 
						|
    def _read_eof(self):
 | 
						|
        # We've read to the end of the file
 | 
						|
        # We check that the computed CRC and size of the
 | 
						|
        # uncompressed data matches the stored values.  Note that the size
 | 
						|
        # stored is the true file size mod 2**32.
 | 
						|
        crc32, isize = struct.unpack("<II", _read_exact(self._fp, 8))
 | 
						|
        if crc32 != self._crc:
 | 
						|
            raise BadGzipFile("CRC check failed %s != %s" % (hex(crc32),
 | 
						|
                                                             hex(self._crc)))
 | 
						|
        elif isize != (self._stream_size & 0xffffffff):
 | 
						|
            raise BadGzipFile("Incorrect length of data produced")
 | 
						|
 | 
						|
        # Gzip files can be padded with zeroes and still have archives.
 | 
						|
        # Consume all zero bytes and set the file position to the first
 | 
						|
        # non-zero byte. See http://www.gzip.org/#faq8
 | 
						|
        c = b"\x00"
 | 
						|
        while c == b"\x00":
 | 
						|
            c = self._fp.read(1)
 | 
						|
        if c:
 | 
						|
            self._fp.prepend(c)
 | 
						|
 | 
						|
    def _rewind(self):
 | 
						|
        super()._rewind()
 | 
						|
        self._new_member = True
 | 
						|
 | 
						|
 | 
						|
def _create_simple_gzip_header(compresslevel: int,
 | 
						|
                               mtime = None) -> bytes:
 | 
						|
    """
 | 
						|
    Write a simple gzip header with no extra fields.
 | 
						|
    :param compresslevel: Compresslevel used to determine the xfl bytes.
 | 
						|
    :param mtime: The mtime (must support conversion to a 32-bit integer).
 | 
						|
    :return: A bytes object representing the gzip header.
 | 
						|
    """
 | 
						|
    if mtime is None:
 | 
						|
        mtime = time.time()
 | 
						|
    if compresslevel == _COMPRESS_LEVEL_BEST:
 | 
						|
        xfl = 2
 | 
						|
    elif compresslevel == _COMPRESS_LEVEL_FAST:
 | 
						|
        xfl = 4
 | 
						|
    else:
 | 
						|
        xfl = 0
 | 
						|
    # Pack ID1 and ID2 magic bytes, method (8=deflate), header flags (no extra
 | 
						|
    # fields added to header), mtime, xfl and os (255 for unknown OS).
 | 
						|
    return struct.pack("<BBBBLBB", 0x1f, 0x8b, 8, 0, int(mtime), xfl, 255)
 | 
						|
 | 
						|
 | 
						|
def compress(data, compresslevel=_COMPRESS_LEVEL_BEST, *, mtime=None):
 | 
						|
    """Compress data in one shot and return the compressed string.
 | 
						|
 | 
						|
    compresslevel sets the compression level in range of 0-9.
 | 
						|
    mtime can be used to set the modification time. The modification time is
 | 
						|
    set to the current time by default.
 | 
						|
    """
 | 
						|
    if mtime == 0:
 | 
						|
        # Use zlib as it creates the header with 0 mtime by default.
 | 
						|
        # This is faster and with less overhead.
 | 
						|
        return zlib.compress(data, level=compresslevel, wbits=31)
 | 
						|
    header = _create_simple_gzip_header(compresslevel, mtime)
 | 
						|
    trailer = struct.pack("<LL", zlib.crc32(data), (len(data) & 0xffffffff))
 | 
						|
    # Wbits=-15 creates a raw deflate block.
 | 
						|
    return header + zlib.compress(data, wbits=-15) + trailer
 | 
						|
 | 
						|
 | 
						|
def decompress(data):
 | 
						|
    """Decompress a gzip compressed string in one shot.
 | 
						|
    Return the decompressed string.
 | 
						|
    """
 | 
						|
    decompressed_members = []
 | 
						|
    while True:
 | 
						|
        fp = io.BytesIO(data)
 | 
						|
        if _read_gzip_header(fp) is None:
 | 
						|
            return b"".join(decompressed_members)
 | 
						|
        # Use a zlib raw deflate compressor
 | 
						|
        do = zlib.decompressobj(wbits=-zlib.MAX_WBITS)
 | 
						|
        # Read all the data except the header
 | 
						|
        decompressed = do.decompress(data[fp.tell():])
 | 
						|
        if not do.eof or len(do.unused_data) < 8:
 | 
						|
            raise EOFError("Compressed file ended before the end-of-stream "
 | 
						|
                           "marker was reached")
 | 
						|
        crc, length = struct.unpack("<II", do.unused_data[:8])
 | 
						|
        if crc != zlib.crc32(decompressed):
 | 
						|
            raise BadGzipFile("CRC check failed")
 | 
						|
        if length != (len(decompressed) & 0xffffffff):
 | 
						|
            raise BadGzipFile("Incorrect length of data produced")
 | 
						|
        decompressed_members.append(decompressed)
 | 
						|
        data = do.unused_data[8:].lstrip(b"\x00")
 | 
						|
 | 
						|
 | 
						|
def main():
 | 
						|
    from argparse import ArgumentParser
 | 
						|
    parser = ArgumentParser(description=
 | 
						|
        "A simple command line interface for the gzip module: act like gzip, "
 | 
						|
        "but do not delete the input file.")
 | 
						|
    group = parser.add_mutually_exclusive_group()
 | 
						|
    group.add_argument('--fast', action='store_true', help='compress faster')
 | 
						|
    group.add_argument('--best', action='store_true', help='compress better')
 | 
						|
    group.add_argument("-d", "--decompress", action="store_true",
 | 
						|
                        help="act like gunzip instead of gzip")
 | 
						|
 | 
						|
    parser.add_argument("args", nargs="*", default=["-"], metavar='file')
 | 
						|
    args = parser.parse_args()
 | 
						|
 | 
						|
    compresslevel = _COMPRESS_LEVEL_TRADEOFF
 | 
						|
    if args.fast:
 | 
						|
        compresslevel = _COMPRESS_LEVEL_FAST
 | 
						|
    elif args.best:
 | 
						|
        compresslevel = _COMPRESS_LEVEL_BEST
 | 
						|
 | 
						|
    for arg in args.args:
 | 
						|
        if args.decompress:
 | 
						|
            if arg == "-":
 | 
						|
                f = GzipFile(filename="", mode="rb", fileobj=sys.stdin.buffer)
 | 
						|
                g = sys.stdout.buffer
 | 
						|
            else:
 | 
						|
                if arg[-3:] != ".gz":
 | 
						|
                    sys.exit(f"filename doesn't end in .gz: {arg!r}")
 | 
						|
                f = open(arg, "rb")
 | 
						|
                g = builtins.open(arg[:-3], "wb")
 | 
						|
        else:
 | 
						|
            if arg == "-":
 | 
						|
                f = sys.stdin.buffer
 | 
						|
                g = GzipFile(filename="", mode="wb", fileobj=sys.stdout.buffer,
 | 
						|
                             compresslevel=compresslevel)
 | 
						|
            else:
 | 
						|
                f = builtins.open(arg, "rb")
 | 
						|
                g = open(arg + ".gz", "wb")
 | 
						|
        while True:
 | 
						|
            chunk = f.read(io.DEFAULT_BUFFER_SIZE)
 | 
						|
            if not chunk:
 | 
						|
                break
 | 
						|
            g.write(chunk)
 | 
						|
        if g is not sys.stdout.buffer:
 | 
						|
            g.close()
 | 
						|
        if f is not sys.stdin.buffer:
 | 
						|
            f.close()
 | 
						|
 | 
						|
if __name__ == '__main__':
 | 
						|
    main()
 |