def testRead(self):
"""Test the read functionality."""
test_path = self._GetTestFilePath(['syslog.gz'])
self._SkipIfPathNotExists(test_path)
test_file = gzipfile.GzipCompressedStream()
test_os_path_spec = path_spec_factory.Factory.NewPathSpec(
definitions.TYPE_INDICATOR_OS, location=test_path)
file_object = resolver.Resolver.OpenFileObject(test_os_path_spec)
test_file.Open(file_object)
try:
test_file.seek(167, os.SEEK_SET)
self.assertEqual(test_file.get_offset(), 167)
expected_data = (
b'Jan 22 07:53:01 myhostname.myhost.com CRON[31051]: (root) CMD '
b'(touch /var/run/crond.somecheck)\n')
data = test_file.read(95)
self.assertEqual(data, expected_data)
self.assertEqual(test_file.get_offset(), 262)
finally:
test_file.close()
def testSeek(self):
"""Test the seek functionality."""
test_path = self._GetTestFilePath(['syslog.gz'])
self._SkipIfPathNotExists(test_path)
test_file = gzipfile.GzipCompressedStream()
test_os_path_spec = path_spec_factory.Factory.NewPathSpec(
definitions.TYPE_INDICATOR_OS, location=test_path)
file_object = resolver.Resolver.OpenFileObject(test_os_path_spec)
test_file.Open(file_object)
try:
test_file.seek(177)
self.assertEqual(test_file.read(5), b'53:01')
self.assertEqual(test_file.get_offset(), 182)
test_file.seek(-10, os.SEEK_END)
self.assertEqual(test_file.read(5), b'times')
test_file.seek(2, os.SEEK_CUR)
self.assertEqual(test_file.read(2), b'--')
# Conforming to the POSIX seek the offset can exceed the file size
# but reading will result in no data being returned.
test_file.seek(2000, os.SEEK_SET)
self.assertEqual(test_file.get_offset(), 2000)
self.assertEqual(test_file.read(2), b'')
# Test with an invalid offset.
with self.assertRaises(IOError):
test_file.seek(-10, os.SEEK_SET)
# On error the offset should not change.
self.assertEqual(test_file.get_offset(), 2000)
# Test with an invalid whence.
with self.assertRaises(IOError):
test_file.seek(10, 5)
# On error the offset should not change.
self.assertEqual(test_file.get_offset(), 2000)
finally:
test_file.close()
def testOpenClose(self):
"""Test the Open and Close functions."""
test_path = self._GetTestFilePath(['syslog.gz'])
self._SkipIfPathNotExists(test_path)
test_file = gzipfile.GzipCompressedStream()
test_os_path_spec = path_spec_factory.Factory.NewPathSpec(
definitions.TYPE_INDICATOR_OS, location=test_path)
file_object = resolver.Resolver.OpenFileObject(test_os_path_spec)
test_file.Open(file_object)
try:
self.assertEqual(len(test_file.members), 1)
finally:
test_file.close()
def testReadCorrupt(self):
"""Tests reading a file that is corrupt."""
# The corrupt gzip has no member footer.
test_path = self._GetTestFilePath(['corrupt1.gz'])
self._SkipIfPathNotExists(test_path)
test_file = gzipfile.GzipCompressedStream()
test_os_path_spec = path_spec_factory.Factory.NewPathSpec(
definitions.TYPE_INDICATOR_OS, location=test_path)
file_object = resolver.Resolver.OpenFileObject(test_os_path_spec)
test_file.Open(file_object)
try:
self.assertEqual(test_file.uncompressed_data_size, 2994187)
finally:
test_file.close()
def _OpenFileObject(self, path_spec):
"""Opens the file-like object defined by path specification.
Args:
path_spec (PathSpec): path specification.
Returns:
pyvde.volume: gzip file-like object.
Raises:
PathSpecError: if the path specification is incorrect.
"""
if not path_spec.HasParent():
raise errors.PathSpecError(
'Unsupported path specification without parent.')
file_object = resolver.Resolver.OpenFileObject(
path_spec.parent, resolver_context=self._resolver_context)
gzip_compressed_stream = gzipfile.GzipCompressedStream()
gzip_compressed_stream.Open(file_object)
return gzip_compressed_stream
def testReadMultipleMembers(self):
"""Tests reading a file that contains multiple gzip members."""
test_path = self._GetTestFilePath(['fsevents_000000000000b208'])
self._SkipIfPathNotExists(test_path)
test_file = gzipfile.GzipCompressedStream()
test_os_path_spec = path_spec_factory.Factory.NewPathSpec(
definitions.TYPE_INDICATOR_OS, location=test_path)
file_object = resolver.Resolver.OpenFileObject(test_os_path_spec)
test_file.Open(file_object)
try:
self.assertEqual(len(test_file.members), 2)
file_start = test_file.read(4)
self.assertEqual(file_start, b'1SLD')
# Read the end of the second member
test_file.seek(506631 - 4)
file_end = test_file.read(4)
self.assertEqual(file_end, b'\x02\x00\x80\x00')
# Seek backwards, and read across a member boundary.
test_file.seek(28530)
self.assertEqual(test_file.read(6), b'OS\x00P\x07\x00')
# Read with a size greater than the file size.
test_file.seek(0)
data = test_file.read(size=506631 + 4)
self.assertEqual(len(data), 506631)
self.assertEqual(data[-4:], b'\x02\x00\x80\x00')
finally:
test_file.close()