Source code for dfvfs.analyzer.fat_analyzer_helper
# -*- coding: utf-8 -*-
"""The FAT 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 FATAnalyzerHelper(analyzer_helper.AnalyzerHelper):
"""FAT analyzer helper."""
FORMAT_CATEGORIES = frozenset([
definitions.FORMAT_CATEGORY_FILE_SYSTEM])
TYPE_INDICATOR = definitions.TYPE_INDICATOR_FAT
[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)
# Boot sector signature.
format_specification.AddNewSignature(b'\x55\xaa', offset=510)
# FAT-12 and FAT-16 file system hint.
format_specification.AddNewSignature(b'FAT12 ', offset=54)
format_specification.AddNewSignature(b'FAT16 ', offset=54)
# FAT-32 file system hint.
format_specification.AddNewSignature(b'FAT32 ', offset=82)
# exFAT file system signature.
format_specification.AddNewSignature(b'EXFAT ', offset=3)
return format_specification
[docs]
def IsEnabled(self):
"""Determines if the analyzer helper is enabled.
Returns:
bool: True if the analyzer helper is enabled.
"""
return definitions.PREFERRED_FAT_BACK_END == self.TYPE_INDICATOR
analyzer.Analyzer.RegisterHelper(FATAnalyzerHelper())