# -*- coding: utf-8 -*-
"""The GUID Partition Table (GPT) file entry implementation."""
from dfvfs.lib import definitions
from dfvfs.lib import errors
from dfvfs.vfs import file_entry
from dfvfs.vfs import gpt_directory
[docs]
class GPTFileEntry(file_entry.FileEntry):
"""File system file entry that uses pyvsgpt."""
TYPE_INDICATOR = definitions.TYPE_INDICATOR_GPT
[docs]
def __init__(
self, resolver_context, file_system, path_spec, entry_index=None,
is_root=False, is_virtual=False, vsgpt_partition=None):
"""Initializes a file entry.
Args:
resolver_context (Context): resolver context.
file_system (FileSystem): file system.
path_spec (PathSpec): path specification.
entry_index (Optional[int]): GPT partition entry index or None.
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
vsgpt_partition (Optional[pyvsgpt.partition]): a GPT partition.
Raises:
BackEndError: when GPT partition is missing for a non-virtual file entry.
"""
if not is_virtual and vsgpt_partition is None:
vsgpt_partition = file_system.GetGPTPartitionByPathSpec(path_spec)
if not is_virtual and vsgpt_partition is None:
raise errors.BackEndError(
'Missing vsgpt partition in non-virtual file entry.')
super(GPTFileEntry, self).__init__(
resolver_context, file_system, path_spec, is_root=is_root,
is_virtual=is_virtual)
self._entry_index = entry_index
self._name = None
self._vsgpt_partition = vsgpt_partition
if self._is_virtual:
self.entry_type = definitions.FILE_ENTRY_TYPE_DIRECTORY
else:
self.entry_type = definitions.FILE_ENTRY_TYPE_FILE
def _GetDirectory(self):
"""Retrieves the directory.
Returns:
GPTDirectory: a directory.
"""
if self.entry_type != definitions.FILE_ENTRY_TYPE_DIRECTORY:
return None
return gpt_directory.GPTDirectory(self._file_system, self.path_spec)
def _GetSubFileEntries(self):
"""Retrieves sub file entries.
Yields:
GPTFileEntry: a sub file entry.
"""
if self._directory is None:
self._directory = self._GetDirectory()
if self._directory:
for path_spec in self._directory.entries:
yield GPTFileEntry(self._resolver_context, self._file_system, path_spec)
@property
def name(self):
"""str: name of the file entry, without the full path."""
if self._name is None:
self._name = ''
# Prefer generating the name seeing that the GPT back-end supports
# aliases, such as "/p1" and "/gpt{GUID}".
if self._entry_index is not None:
gpt_entry_index = self._entry_index + 1
self._name = f'p{gpt_entry_index:d}'
else:
location = getattr(self.path_spec, 'location', None)
if location is not None:
self._name = self._file_system.BasenamePath(location)
return self._name
@property
def size(self):
"""int: size of the file entry in bytes or None if not available."""
if self._vsgpt_partition is None:
return None
return self._vsgpt_partition.size
[docs]
def GetGPTPartition(self):
"""Retrieves the GPT partition.
Returns:
pyvsgpt.partition: a GPT partition.
"""
return self._vsgpt_partition
[docs]
def GetParentFileEntry(self):
"""Retrieves the parent file entry.
Returns:
GPTFileEntry: parent file entry or None if not available.
"""
if self._entry_index is None:
return None
return self._file_system.GetRootFileEntry()