xz_mod module

Impersonate the real xz module, which has yet to be written and/or added to CPython, by using the xz binary.

exception xz_mod.DecompressionError

Bases: Exception

An exception to raise if there is a problem decompressing data. Should be rare but not nonexistent in practice.

class xz_mod.Xz_ctypes

Bases: object

A class to compress and decompress xz format, using ctypes to access liblzma.

LZMA_BUF_ERROR = 10

LZMA_CHECK_CRC32 = 1

LZMA_DATA_ERROR = 9

LZMA_FORMAT_ERROR = 7

LZMA_LIB = <CDLL 'liblzma.so.5', handle 25b1930>

LZMA_LIBPATH = 'liblzma.so.5'

LZMA_MEMLIMIT_ERROR = 6

LZMA_MEM_ERROR = 5

LZMA_NO_CHECK = 2

LZMA_OK = 0

LZMA_OPTIONS_ERROR = 8

LZMA_PRESET_DEFAULT = 6

LZMA_PROG_ERROR = 11

LZMA_TELL_NO_CHECK = 1

LZMA_TELL_UNSUPPORTED_CHECK = 2

LZMA_UNSUPPORTED_CHECK = 3

classmethod class_init()

Initialize the class.

classmethod compress(input_data)

Compress data into xz format using ctypes to access liblzma.so.

classmethod declare_c_function(library, name, argtypes=None, restype=None)

Extract functions from liblzma.

classmethod decompress(input_data, max_result_size=67108864)

Uncompress data from xz format using ctypes to access liblzma.so.

error_dict = {0: 'LZMA_OK', 1: 'LZMA_TELL_NO_CHECK', 2: 'LZMA_TELL_UNSUPPORTED_CHECK', 3: 'LZMA_UNSUPPORTED_CHECK', 5: 'LZMA_MEM_ERROR', 6: 'LZMA_MEMLIMIT_ERROR: Memory usage limit was reached.  minimum required memlimit value was stored to *memlimit', 7: "LZMA_FORMAT_ERROR: Magic bytes don't match, thus the given buffer cannot be Stream Header.", 8: 'LZMA_OPTIONS_ERROR', 9: 'LZMA_DATA_ERROR', 10: 'LZMA_BUF_ERROR: Output buffer was too small', 11: 'LZMA_PROG_ERROR'}

funcs = {'lzma_easy_buffer_encode': <_FuncPtr object>, 'lzma_stream_buffer_bound': <_FuncPtr object>, 'lzma_stream_buffer_decode': <_FuncPtr object>}

classmethod get_xz_error(ret_xz)

Decode an lzma_ret enum to an at-least-somewhat-descriptive string.

long_message = 'LZMA_MEMLIMIT_ERROR: Memory usage limit was reached.  minimum required memlimit value was stored to *memlimit'

long_string = "LZMA_FORMAT_ERROR: Magic bytes don't match, thus the given buffer cannot be Stream Header."

xz_mod.compress(data)

Compress a block of data using lzma/xz.

xz_mod.decompress(data)

Decompress a block of data using lzma/xz.

xz_mod.find_xz()

Find the xz binary, if any.

xz_mod.use_ctypes()

Return True if we should use the ctypes version.

xz_mod.use_lzma()

Return True if we should use the lzma module.

xz_mod.use_popen()

Return True if we should use the popen version.

xz_mod.use_subprocess()

Return True if we should use the subprocess module.