# -*- coding: utf-8 -*-
"""The FAT file entry implementation."""
import pyfsfat
from dfdatetime import definitions as dfdatetime_definitions
from dfdatetime import fat_date_time as dfdatetime_fat_date_time
from dfvfs.lib import definitions
from dfvfs.lib import errors
from dfvfs.path import fat_path_spec
from dfvfs.resolver import resolver
from dfvfs.vfs import attribute
from dfvfs.vfs import extent
from dfvfs.vfs import fat_directory
from dfvfs.vfs import file_entry
[docs]
class FATFileEntry(file_entry.FileEntry):
"""File system file entry that uses pyfsfat."""
TYPE_INDICATOR = definitions.TYPE_INDICATOR_FAT
_FILE_SYSTEM_FORMAT_EXFAT = pyfsfat.file_system_formats.EXFAT
[docs]
def __init__(
self, resolver_context, file_system, path_spec, fsfat_file_entry=None,
is_root=False, is_virtual=False):
"""Initializes a file entry.
Args:
resolver_context (Context): resolver context.
file_system (FileSystem): file system.
path_spec (PathSpec): path specification.
fsfat_file_entry (Optional[pyfsfat.file_entry]): FAT file entry.
is_root (Optional[bool]): True if the file entry is the root file entry
of the corresponding file system.
is_virtual (Optional[bool]): True if the file entry is a virtual file
entry emulated by the corresponding file system.
Raises:
BackEndError: if the pyfsfat file entry is missing.
"""
if not fsfat_file_entry:
fsfat_file_entry = file_system.GetFATFileEntryByPathSpec(path_spec)
if not fsfat_file_entry:
raise errors.BackEndError('Missing pyfsfat file entry.')
fsfat_volume = file_system.GetFATVolume()
if is_root:
file_entry_name = ''
else:
file_entry_name = fsfat_file_entry.name
super(FATFileEntry, self).__init__(
resolver_context, file_system, path_spec, is_root=is_root,
is_virtual=is_virtual)
self._file_system_format = fsfat_volume.get_file_system_format()
self._fsfat_file_entry = fsfat_file_entry
self._name = file_entry_name
file_attribute_flags = fsfat_file_entry.file_attribute_flags
if (file_attribute_flags is None or
file_attribute_flags & pyfsfat.file_attribute_flags.DIRECTORY):
self.entry_type = definitions.FILE_ENTRY_TYPE_DIRECTORY
elif file_attribute_flags & pyfsfat.file_attribute_flags.DEVICE:
self.entry_type = definitions.FILE_ENTRY_TYPE_DEVICE
else:
self.entry_type = definitions.FILE_ENTRY_TYPE_FILE
def _GetDirectory(self):
"""Retrieves a directory.
Returns:
FATDirectory: directory or None if not available.
"""
if self.entry_type != definitions.FILE_ENTRY_TYPE_DIRECTORY:
return None
return fat_directory.FATDirectory(
self._file_system, self.path_spec, self._fsfat_file_entry)
def _GetStatAttribute(self):
"""Retrieves a stat attribute.
Returns:
StatAttribute: a stat attribute or None if not available.
"""
stat_attribute = attribute.StatAttribute()
stat_attribute.inode_number = self._fsfat_file_entry.identifier
stat_attribute.size = self._fsfat_file_entry.size
stat_attribute.type = self.entry_type
return stat_attribute
def _GetSubFileEntries(self):
"""Retrieves a sub file entries generator.
Yields:
FATFileEntry: a sub file entry.
"""
if self._directory is None:
self._directory = self._GetDirectory()
if self._directory:
for path_spec in self._directory.entries:
yield FATFileEntry(self._resolver_context, self._file_system, path_spec)
@property
def access_time(self):
"""dfdatetime.DateTimeValues: access time or None if not available."""
timestamp = self._fsfat_file_entry.get_access_time_as_integer()
# Access time can be None if not present and 0 if not set.
if not timestamp:
return None
if self._file_system_format == self._FILE_SYSTEM_FORMAT_EXFAT:
precision = dfdatetime_definitions.PRECISION_10_MILLISECONDS
else:
precision = dfdatetime_definitions.PRECISION_1_DAY
return dfdatetime_fat_date_time.FATTimestamp(
precision=precision, timestamp=timestamp)
@property
def creation_time(self):
"""dfdatetime.DateTimeValues: creation time or None if not available."""
timestamp = self._fsfat_file_entry.get_creation_time_as_integer()
# Creation time can be None if not present and 0 if not set.
if not timestamp:
return None
return dfdatetime_fat_date_time.FATTimestamp(
precision=dfdatetime_definitions.PRECISION_10_MILLISECONDS,
timestamp=timestamp)
@property
def name(self):
"""str: name of the file entry, which does not include the full path."""
return self._name
@property
def modification_time(self):
"""dfdatetime.DateTimeValues: modification time or None if not available."""
timestamp = self._fsfat_file_entry.get_modification_time_as_integer()
# Modification time can be None if not present and 0 if not set.
if not timestamp:
return None
if self._file_system_format == self._FILE_SYSTEM_FORMAT_EXFAT:
precision = dfdatetime_definitions.PRECISION_10_MILLISECONDS
else:
precision = dfdatetime_definitions.PRECISION_2_SECONDS
return dfdatetime_fat_date_time.FATTimestamp(
precision=precision, timestamp=timestamp)
@property
def size(self):
"""int: size of the file entry in bytes or None if not available."""
return self._fsfat_file_entry.size
[docs]
def GetExtents(self):
"""Retrieves the extents.
Returns:
list[Extent]: the extents.
"""
if self.entry_type != definitions.FILE_ENTRY_TYPE_FILE:
return []
extents = []
for extent_index in range(self._fsfat_file_entry.number_of_extents):
extent_offset, extent_size, extent_flags = (
self._fsfat_file_entry.get_extent(extent_index))
if extent_flags & 0x1:
extent_type = definitions.EXTENT_TYPE_SPARSE
else:
extent_type = definitions.EXTENT_TYPE_DATA
data_stream_extent = extent.Extent(
extent_type=extent_type, offset=extent_offset, size=extent_size)
extents.append(data_stream_extent)
return extents
[docs]
def GetFileObject(self, data_stream_name=''):
"""Retrieves a file-like object of a specific data stream.
Args:
data_stream_name (Optional[str]): name of the data stream, where an empty
string represents the default data stream.
Returns:
FileIO: a file-like object or None if not available.
"""
if self.entry_type != definitions.FILE_ENTRY_TYPE_FILE or data_stream_name:
return None
return resolver.Resolver.OpenFileObject(
self.path_spec, resolver_context=self._resolver_context)
[docs]
def GetFATFileEntry(self):
"""Retrieves the FAT file entry.
Returns:
pyfsfat.file_entry: FAT file entry.
"""
return self._fsfat_file_entry
[docs]
def GetParentFileEntry(self):
"""Retrieves the parent file entry.
Returns:
FATFileEntry: parent file entry or None if not available.
"""
parent_location = None
location = getattr(self.path_spec, 'location', None)
if location is not None:
parent_location = self._file_system.DirnamePath(location)
if parent_location == '':
parent_location = self._file_system.PATH_SEPARATOR
parent_path_spec = getattr(self.path_spec, 'parent', None)
path_spec = fat_path_spec.FATPathSpec(
location=parent_location, parent=parent_path_spec)
is_root = bool(parent_location == self._file_system.LOCATION_ROOT)
return FATFileEntry(
self._resolver_context, self._file_system, path_spec, is_root=is_root)