N $lad*j"Tځz@ؔţ "d?3"""Interface to the liblzma compression library. This module provides a class for reading and writing compressed files, classes for incremental (de)compression, and convenience functions for one-shot (de)compression. These classes and functions support both the XZ and legacy LZMA container formats, as well as raw compressed data streams. """ __all__ = [ "CHECK_NONE", "CHECK_CRC32", "CHECK_CRC64", "CHECK_SHA256", "CHECK_ID_MAX", "CHECK_UNKNOWN", "FILTER_LZMA1", "FILTER_LZMA2", "FILTER_DELTA", "FILTER_X86", "FILTER_IA64", "FILTER_ARM", "FILTER_ARMTHUMB", "FILTER_POWERPC", "FILTER_SPARC", "FORMAT_AUTO", "FORMAT_XZ", "FORMAT_ALONE", "FORMAT_RAW", "MF_HC3", "MF_HC4", "MF_BT2", "MF_BT3", "MF_BT4", "MODE_FAST", "MODE_NORMAL", "PRESET_DEFAULT", "PRESET_EXTREME", "LZMACompressor", "LZMADecompressor", "LZMAFile", "LZMAError", "open", "compress", "decompress", "is_check_supported", ] import builtins import io import os from _lzma import * from _lzma import _encode_filter_properties, _decode_filter_properties import _compression _MODE_CLOSED = 0 _MODE_READ = 1 # Value 2 no longer used _MODE_WRITE = 3 class LZMAFile(_compression.BaseStream): """A file object providing transparent LZMA (de)compression. An LZMAFile can act as a wrapper for an existing file object, or refer directly to a named file on disk. Note that LZMAFile provides a *binary* file interface - data read is returned as bytes, and data to be written must be given as bytes. """ def __init__(self, filename=None, mode="r", *, format=None, check=-1, preset=None, filters=None): """Open an LZMA-compressed file in binary mode. filename can be either an actual file name (given as a str, bytes, or PathLike object), in which case the named file is opened, or it can be an existing file object to read from or write to. mode can be "r" for reading (default), "w" for (over)writing, "x" for creating exclusively, or "a" for appending. These can equivalently be given as "rb", "wb", "xb" and "ab" respectively. format specifies the container format to use for the file. If mode is "r", this defaults to FORMAT_AUTO. Otherwise, the default is FORMAT_XZ. check specifies the integrity check to use. This argument can only be used when opening a file for writing. For FORMAT_XZ, the default is CHECK_CRC64. FORMAT_ALONE and FORMAT_RAW do not support integrity checks - for these formats, check must be omitted, or be CHECK_NONE. When opening a file for reading, the *preset* argument is not meaningful, and should be omitted. The *filters* argument should also be omitted, except when format is FORMAT_RAW (in which case it is required). When opening a file for writing, the settings used by the compressor can be specified either as a preset compression level (with the *preset* argument), or in detail as a custom filter chain (with the *filters* argument). For FORMAT_XZ and FORMAT_ALONE, the default is to use the PRESET_DEFAULT preset level. For FORMAT_RAW, the caller must always specify a filter chain; the raw compressor does not support preset compression levels. preset (if provided) should be an integer in the range 0-9, optionally OR-ed with the constant PRESET_EXTREME. filters (if provided) should be a sequence of dicts. Each dict should have an entry for "id" indicating ID of the filter, plus additional entries for options to the filter. """ self._fp = None self._closefp = False self._mode = _MODE_CLOSED if mode in ("r", "rb"): if check != -1: raise ValueError("Cannot specify an integrity check " "when opening a file for reading") if preset is not None: