def __iter__(self): # pylint: disable=too-many-branches
"""Iterate over messages in the file"""
logger.debug("Starting File Read")
logger.debug("File Position: %d File Counter: %d File Name: %s",
self.file_position, self.counter, self.filename)
cached_mtime = 0
cached_file_pos = 0
corruption_check_try = True
self._open_file()
found_data = False
while not self.stop_reading.isSet() or corruption_check_try: # pylint: disable=too-many-nested-blocks
os_stat = os.stat(self.filename)
mtime = os_stat.st_mtime
if mtime != cached_mtime and os_stat.st_size or corruption_check_try:
cached_mtime = mtime
corruption_check_try = False
while dltlib.dlt_file_read(ctypes.byref(self), self.verbose) >= DLT_RETURN_OK:
found_data = True
if self.filter and dltlib.dlt_message_filter_check(
ctypes.byref(self.msg), self.filter, 0) != DLT_RETURN_TRUE:
continue
index = self.position
msg = self[index]
if not index % 100000:
self._log_message_progress()
yield msg
if cached_file_pos != self.file_position:
# We were able to read messages, don't do a corrupt message check yet.
corruption_check_try = True
cached_file_pos = self.file_position
else:
next_header_position = self._find_next_header()
if next_header_position:
if self.file_position == next_header_position:
if not self.live_run:
logger.warning("Incomplete message while parsing DLT file at %s", self.file_position)
break
else:
logger.warning("Found a corrupt message at %s, skipping it", self.file_position)
self.file_position = next_header_position
self.corrupt_msg_count += 1
corruption_check_try = True
# Wait for further messages to determine if corrupt, else just end of file
else:
if not self.live_run:
logger.info("End of file reached at %s", self.file_position)
break
time.sleep(0.1)
if not found_data:
raise IOError(DLT_EMPTY_FILE_ERROR)
def generate_index(self):
"""Generate an index for the loaded DLT file
:returns: True if file had been previously read and the index is
successfully generated, otherwise False
:rtype: bool
"""
if not self.filename:
return False
self.indexed = False
if dltlib.dlt_file_open(ctypes.byref(self), self.filename,
self.verbose) >= DLT_RETURN_OK:
# load, analyse data file and create index list
if self.file_length == 0:
raise IOError(DLT_EMPTY_FILE_ERROR)
while self.file_position < self.file_length:
ret = dltlib.dlt_file_read(ctypes.byref(self), self.verbose)
if ret < DLT_RETURN_OK:
# - This can happen if either the frame's storage
# header could not be read correctly or the frame is
# corrupt. If the frame's storage header could not
# be read correctly we try to get the next storage
# header and continue indexing
next_header_position = self._find_next_header()
if next_header_position:
if self.file_position == next_header_position: # pylint: disable=no-else-break
# - This this implies that dltlib.dlt_read_file()
# returned due to an error other than invalid storage
# header because we already were at the correct
# header_position in the last iteration. So, we
# need to break out of the read/index loop.
break
else:
self.file_position = next_header_position
self.corrupt_msg_count += 1
else:
break
self.indexed = True
else:
raise IOError(cDLT_FILE_NOT_OPEN_ERROR)
return self.indexed