def NewFileObject(self, resolver_context):
"""Creates a new file-like object.
Args:
resolver_context (Context): resolver context.
Returns:
FileIO: file-like object.
"""
return vshadow_file_io.VShadowFile(resolver_context)
def NewFileObject(self, resolver_context, path_spec):
"""Creates a new file input/output (IO) object.
Args:
resolver_context (Context): resolver context.
path_spec (PathSpec): a path specification.
Returns:
FileIO: file input/output (IO) object.
"""
return vshadow_file_io.VShadowFile(resolver_context, path_spec)
def testOpenClose(self):
"""Test the open and close functionality."""
path_spec = vshadow_path_spec.VShadowPathSpec(
parent=self._qcow_path_spec, store_index=1)
file_object = vshadow_file_io.VShadowFile(self._resolver_context,
path_spec)
file_object.Open()
self.assertEqual(file_object.get_size(), 0x40000000)
path_spec = vshadow_path_spec.VShadowPathSpec(
parent=self._qcow_path_spec, store_index=13)
file_object = vshadow_file_io.VShadowFile(self._resolver_context,
path_spec)
with self.assertRaises(errors.PathSpecError):
file_object.Open()
path_spec = vshadow_path_spec.VShadowPathSpec(
location='/vss1', parent=self._qcow_path_spec)
file_object = vshadow_file_io.VShadowFile(self._resolver_context,
path_spec)
file_object.Open()
self.assertEqual(file_object.get_size(), 0x40000000)
path_spec = vshadow_path_spec.VShadowPathSpec(
location='/vss0', parent=self._qcow_path_spec)
file_object = vshadow_file_io.VShadowFile(self._resolver_context,
path_spec)
with self.assertRaises(errors.PathSpecError):
file_object.Open()
path_spec = vshadow_path_spec.VShadowPathSpec(
location='/vss13', parent=self._qcow_path_spec)
file_object = vshadow_file_io.VShadowFile(self._resolver_context,
path_spec)
with self.assertRaises(errors.PathSpecError):
file_object.Open()
def testRead(self):
"""Test the read functionality."""
path_spec = vshadow_path_spec.VShadowPathSpec(
parent=self._qcow_path_spec, store_index=1)
file_object = vshadow_file_io.VShadowFile(self._resolver_context,
path_spec)
file_object.Open()
self.assertEqual(file_object.get_size(), 0x40000000)
file_object.seek(0x18e)
expected_data = b'A disk read error occurred\x00\r\nBOOTMGR is missing'
self.assertEqual(file_object.read(47), expected_data)
def testSeek(self):
"""Test the seek functionality."""
path_spec = vshadow_path_spec.VShadowPathSpec(
parent=self._qcow_path_spec, store_index=1)
file_object = vshadow_file_io.VShadowFile(self._resolver_context)
file_object.open(path_spec=path_spec)
self.assertEqual(file_object.get_size(), 0x40000000)
file_object.seek(0x1e0)
self.assertEqual(file_object.get_offset(), 0x1e0)
self.assertEqual(file_object.read(16), b'rl+Alt+Del to re')
self.assertEqual(file_object.get_offset(), 0x1f0)
file_object.seek(-40, os.SEEK_END)
self.assertEqual(file_object.get_offset(), 0x3fffffd8)
self.assertEqual(file_object.read(8), b'Press Ct')
self.assertEqual(file_object.get_offset(), 0x3fffffe0)
file_object.seek(3, os.SEEK_CUR)
self.assertEqual(file_object.get_offset(), 0x3fffffe3)
self.assertEqual(file_object.read(7), b'Alt+Del')
self.assertEqual(file_object.get_offset(), 0x3fffffea)
# Conforming to the POSIX seek the offset can exceed the file size
# but reading will result in no data being returned.
expected_offset = 0x40000000 + 100
file_object.seek(expected_offset, os.SEEK_SET)
self.assertEqual(file_object.get_offset(), expected_offset)
self.assertEqual(file_object.read(20), b'')
with self.assertRaises(IOError):
file_object.seek(-10, os.SEEK_SET)
# On error the offset should not change.
self.assertEqual(file_object.get_offset(), expected_offset)
with self.assertRaises(IOError):
file_object.seek(10, 5)
# On error the offset should not change.
self.assertEqual(file_object.get_offset(), expected_offset)
file_object.close()