Source code for dfvfs.analyzer.gzip_analyzer_helper

"""The GZIP 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 GzipAnalyzerHelper(analyzer_helper.AnalyzerHelper):
    """GZIP analyzer helper."""

    FORMAT_CATEGORIES = frozenset([definitions.FORMAT_CATEGORY_COMPRESSED_STREAM])

    TYPE_INDICATOR = definitions.TYPE_INDICATOR_GZIP


[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)

        # GZIP file signature.
        format_specification.AddNewSignature(b"\x1f\x8b", offset=0)

        return format_specification




analyzer.Analyzer.RegisterHelper(GzipAnalyzerHelper())