Source code for dfvfs.analyzer.tar_analyzer_helper
# -*- coding: utf-8 -*-
"""The TAR format analyzer helper implementation."""
from dfvfs.analyzer import analyzer
from dfvfs.analyzer import analyzer_helper
from dfvfs.analyzer import specification
from dfvfs.lib import definitions
[docs]
class TARAnalyzerHelper(analyzer_helper.AnalyzerHelper):
"""TAR analyzer helper."""
FORMAT_CATEGORIES = frozenset([
definitions.FORMAT_CATEGORY_ARCHIVE])
TYPE_INDICATOR = definitions.TYPE_INDICATOR_TAR
[docs]
def GetFormatSpecification(self):
"""Retrieves the format specification.
Returns:
FormatSpecification: format specification or None if the format cannot
be defined by a specification object.
"""
format_specification = specification.FormatSpecification(
self.type_indicator)
# TAR file signature.
format_specification.AddNewSignature(b'ustar\x00', offset=257)
# Old TAR file signature.
format_specification.AddNewSignature(b'ustar\x20\x20\x00', offset=257)
return format_specification
analyzer.Analyzer.RegisterHelper(TARAnalyzerHelper())