"""
Contains handling of ASC logging files.
Example .asc files:
- https://bitbucket.org/tobylorenz/vector_asc/src/47556e1a6d32c859224ca62d075e1efcc67fa690/src/Vector/ASC/tests/unittests/data/CAN_Log_Trigger_3_2.asc?at=master&fileviewer=file-view-default
- under `test/data/logfile.asc`
"""
import re
from typing import Any, Generator, List, Optional, Dict, Union, TextIO
from datetime import datetime
import time
import logging
from ..message import Message
from ..util import channel2int, len2dlc, dlc2len
from .generic import FileIOMessageWriter, MessageReader
from ..typechecking import StringPathLike
CAN_MSG_EXT = 0x80000000
CAN_ID_MASK = 0x1FFFFFFF
BASE_HEX = 16
BASE_DEC = 10
logger = logging.getLogger("can.io.asc")
[docs]class ASCReader(MessageReader):
"""
Iterator of CAN messages from a ASC logging file. Meta data (comments,
bus statistics, J1939 Transport Protocol messages) is ignored.
"""
file: TextIO
def __init__(
self,
file: Union[StringPathLike, TextIO],
base: str = "hex",
relative_timestamp: bool = True,
*args: Any,
**kwargs: Any,
) -> None:
"""
:param file: a path-like object or as file-like object to read from
If this is a file-like object, is has to opened in text
read mode, not binary read mode.
:param base: Select the base(hex or dec) of id and data.
If the header of the asc file contains base information,
this value will be overwritten. Default "hex".
:param relative_timestamp: Select whether the timestamps are
`relative` (starting at 0.0) or `absolute` (starting at
the system time). Default `True = relative`.
"""
super().__init__(file, mode="r")
if not self.file:
raise ValueError("The given file cannot be None")
self.base = base
self._converted_base = self._check_base(base)
self.relative_timestamp = relative_timestamp
self.date: Optional[str] = None
self.start_time = 0.0
# TODO - what is this used for? The ASC Writer only prints `absolute`
self.timestamps_format: Optional[str] = None
self.internal_events_logged = False
def _extract_header(self) -> None:
for line in self.file:
line = line.strip()
datetime_match = re.match(
r"date\s+\w+\s+(?P<datetime_string>.+)", line, re.IGNORECASE
)
base_match = re.match(
r"base\s+(?P<base>hex|dec)(?:\s+timestamps\s+"
r"(?P<timestamp_format>absolute|relative))?",
line,
re.IGNORECASE,
)
comment_match = re.match(r"//.*", line)
events_match = re.match(
r"(?P<no_events>no)?\s*internal\s+events\s+logged", line, re.IGNORECASE
)
if datetime_match:
self.date = datetime_match.group("datetime_string")
self.start_time = (
0.0
if self.relative_timestamp
else self._datetime_to_timestamp(self.date)
)
continue
elif base_match:
base = base_match.group("base")
timestamp_format = base_match.group("timestamp_format")
self.base = base
self._converted_base = self._check_base(self.base)
self.timestamps_format = timestamp_format or "absolute"
continue
elif comment_match:
continue
elif events_match:
self.internal_events_logged = events_match.group("no_events") is None
break
else:
break
@staticmethod
def _datetime_to_timestamp(datetime_string: str) -> float:
# ugly locale independent solution
month_map = {
"Jan": 1,
"Feb": 2,
"Mar": 3,
"Apr": 4,
"May": 5,
"Jun": 6,
"Jul": 7,
"Aug": 8,
"Sep": 9,
"Oct": 10,
"Nov": 11,
"Dec": 12,
"Mär": 3,
"Mai": 5,
"Okt": 10,
"Dez": 12,
}
for name, number in month_map.items():
datetime_string = datetime_string.replace(name, str(number).zfill(2))
datetime_formats = (
"%m %d %I:%M:%S.%f %p %Y",
"%m %d %I:%M:%S %p %Y",
"%m %d %H:%M:%S.%f %Y",
"%m %d %H:%M:%S %Y",
)
for format_str in datetime_formats:
try:
return datetime.strptime(datetime_string, format_str).timestamp()
except ValueError:
continue
raise ValueError(f"Incompatible datetime string {datetime_string}")
def _extract_can_id(self, str_can_id: str, msg_kwargs: Dict[str, Any]) -> None:
if str_can_id[-1:].lower() == "x":
msg_kwargs["is_extended_id"] = True
can_id = int(str_can_id[0:-1], self._converted_base)
else:
msg_kwargs["is_extended_id"] = False
can_id = int(str_can_id, self._converted_base)
msg_kwargs["arbitration_id"] = can_id
@staticmethod
def _check_base(base: str) -> int:
if base not in ["hex", "dec"]:
raise ValueError('base should be either "hex" or "dec"')
return BASE_DEC if base == "dec" else BASE_HEX
def _process_data_string(
self, data_str: str, data_length: int, msg_kwargs: Dict[str, Any]
) -> None:
frame = bytearray()
data = data_str.split()
for byte in data[:data_length]:
frame.append(int(byte, self._converted_base))
msg_kwargs["data"] = frame
def _process_classic_can_frame(
self, line: str, msg_kwargs: Dict[str, Any]
) -> Message:
# CAN error frame
if line.strip()[0:10].lower() == "errorframe":
# Error Frame
msg_kwargs["is_error_frame"] = True
else:
abr_id_str, direction, rest_of_message = line.split(None, 2)
msg_kwargs["is_rx"] = direction == "Rx"
self._extract_can_id(abr_id_str, msg_kwargs)
if rest_of_message[0].lower() == "r":
# CAN Remote Frame
msg_kwargs["is_remote_frame"] = True
remote_data = rest_of_message.split()
if len(remote_data) > 1:
dlc_str = remote_data[1]
if dlc_str.isdigit():
msg_kwargs["dlc"] = int(dlc_str, self._converted_base)
else:
# Classic CAN Message
try:
# There is data after DLC
_, dlc_str, data = rest_of_message.split(None, 2)
except ValueError:
# No data after DLC
_, dlc_str = rest_of_message.split(None, 1)
data = ""
dlc = dlc2len(int(dlc_str, self._converted_base))
msg_kwargs["dlc"] = dlc
self._process_data_string(data, min(8, dlc), msg_kwargs)
return Message(**msg_kwargs)
def _process_fd_can_frame(self, line: str, msg_kwargs: Dict[str, Any]) -> Message:
channel, direction, rest_of_message = line.split(None, 2)
# See ASCWriter
msg_kwargs["channel"] = int(channel) - 1
msg_kwargs["is_rx"] = direction == "Rx"
# CAN FD error frame
if rest_of_message.strip()[:10].lower() == "errorframe":
# Error Frame
# TODO: maybe use regex to parse BRS, ESI, etc?
msg_kwargs["is_error_frame"] = True
else:
can_id_str, frame_name_or_brs, rest_of_message = rest_of_message.split(
None, 2
)
if frame_name_or_brs.isdigit():
brs = frame_name_or_brs
esi, dlc_str, data_length_str, data = rest_of_message.split(None, 3)
else:
brs, esi, dlc_str, data_length_str, data = rest_of_message.split(
None, 4
)
self._extract_can_id(can_id_str, msg_kwargs)
msg_kwargs["bitrate_switch"] = brs == "1"
msg_kwargs["error_state_indicator"] = esi == "1"
dlc = int(dlc_str, self._converted_base)
data_length = int(data_length_str)
if data_length == 0:
# CAN remote Frame
msg_kwargs["is_remote_frame"] = True
msg_kwargs["dlc"] = dlc
else:
if dlc2len(dlc) != data_length:
logger.warning(
"DLC vs Data Length mismatch %d[%d] != %d",
dlc,
dlc2len(dlc),
data_length,
)
msg_kwargs["dlc"] = data_length
self._process_data_string(data, data_length, msg_kwargs)
return Message(**msg_kwargs)
def __iter__(self) -> Generator[Message, None, None]:
self._extract_header()
for line in self.file:
line = line.strip()
trigger_match = re.match(
r"begin\s+triggerblock\s+\w+\s+(?P<datetime_string>.+)",
line,
re.IGNORECASE,
)
if trigger_match:
datetime_str = trigger_match.group("datetime_string")
self.start_time = (
0.0
if self.relative_timestamp
else self._datetime_to_timestamp(datetime_str)
)
continue
if not re.match(
r"\d+\.\d+\s+(\d+\s+(\w+\s+(Tx|Rx)|ErrorFrame)|CANFD)",
line,
re.ASCII | re.IGNORECASE,
):
# line might be a comment, chip status,
# J1939 message or some other unsupported event
continue
msg_kwargs: Dict[str, Union[float, bool, int]] = {}
try:
_timestamp, channel, rest_of_message = line.split(None, 2)
timestamp = float(_timestamp) + self.start_time
msg_kwargs["timestamp"] = timestamp
if channel == "CANFD":
msg_kwargs["is_fd"] = True
elif channel.isdigit():
# See ASCWriter
msg_kwargs["channel"] = int(channel) - 1
else:
# Not a CAN message. Possible values include "statistic", J1939TP
continue
except ValueError:
# Some other unprocessed or unknown format
continue
if "is_fd" not in msg_kwargs:
msg = self._process_classic_can_frame(rest_of_message, msg_kwargs)
else:
msg = self._process_fd_can_frame(rest_of_message, msg_kwargs)
if msg is not None:
yield msg
self.stop()
[docs]class ASCWriter(FileIOMessageWriter):
"""Logs CAN data to an ASCII log file (.asc).
The measurement starts with the timestamp of the first registered message.
If a message has a timestamp smaller than the previous one or None,
it gets assigned the timestamp that was written for the last message.
It the first message does not have a timestamp, it is set to zero.
"""
file: TextIO
FORMAT_MESSAGE = "{channel} {id:<15} {dir:<4} {dtype} {data}"
FORMAT_MESSAGE_FD = " ".join(
[
"CANFD",
"{channel:>3}",
"{dir:<4}",
"{id:>8} {symbolic_name:>32}",
"{brs}",
"{esi}",
"{dlc:x}",
"{data_length:>2}",
"{data}",
"{message_duration:>8}",
"{message_length:>4}",
"{flags:>8X}",
"{crc:>8}",
"{bit_timing_conf_arb:>8}",
"{bit_timing_conf_data:>8}",
"{bit_timing_conf_ext_arb:>8}",
"{bit_timing_conf_ext_data:>8}",
]
)
FORMAT_START_OF_FILE_DATE = "%a %b %d %I:%M:%S.%f %p %Y"
FORMAT_DATE = "%a %b %d %I:%M:%S.{} %p %Y"
FORMAT_EVENT = "{timestamp: 9.6f} {message}\n"
def __init__(
self,
file: Union[StringPathLike, TextIO],
channel: int = 1,
*args: Any,
**kwargs: Any,
) -> None:
"""
:param file: a path-like object or as file-like object to write to
If this is a file-like object, is has to opened in text
write mode, not binary write mode.
:param channel: a default channel to use when the message does not
have a channel set
"""
if kwargs.get("append", False):
raise ValueError(
f"{self.__class__.__name__} is currently not equipped to "
f"append messages to an existing file."
)
super().__init__(file, mode="w")
self.channel = channel
# write start of file header
now = datetime.now().strftime(self.FORMAT_START_OF_FILE_DATE)
# Note: CANoe requires that the microsecond field only have 3 digits
idx = now.index(".") # Find the index in the string of the decimal
# Keep decimal and first three ms digits (4), remove remaining digits
now = now.replace(now[idx + 4 : now[idx:].index(" ") + idx], "")
self.file.write(f"date {now}\n")
self.file.write("base hex timestamps absolute\n")
self.file.write("internal events logged\n")
# the last part is written with the timestamp of the first message
self.header_written = False
self.last_timestamp = 0.0
self.started = 0.0
[docs] def stop(self) -> None:
# This is guaranteed to not be None since we raise ValueError in __init__
if not self.file.closed:
self.file.write("End TriggerBlock\n")
super().stop()
[docs] def log_event(self, message: str, timestamp: Optional[float] = None) -> None:
"""Add a message to the log file.
:param message: an arbitrary message
:param timestamp: the absolute timestamp of the event
"""
if not message: # if empty or None
logger.debug("ASCWriter: ignoring empty message")
return
# this is the case for the very first message:
if not self.header_written:
self.last_timestamp = timestamp or 0.0
self.started = self.last_timestamp
mlsec = repr(self.last_timestamp).split(".")[1][:3]
formatted_date = time.strftime(
self.FORMAT_DATE.format(mlsec), time.localtime(self.last_timestamp)
)
self.file.write(f"Begin Triggerblock {formatted_date}\n")
self.header_written = True
self.log_event("Start of measurement") # caution: this is a recursive call!
# Use last known timestamp if unknown
if timestamp is None:
timestamp = self.last_timestamp
# turn into relative timestamps if necessary
if timestamp >= self.started:
timestamp -= self.started
line = self.FORMAT_EVENT.format(timestamp=timestamp, message=message)
self.file.write(line)
[docs] def on_message_received(self, msg: Message) -> None:
if msg.is_error_frame:
self.log_event(f"{self.channel} ErrorFrame", msg.timestamp)
return
if msg.is_remote_frame:
dtype = f"r {msg.dlc:x}" # New after v8.5
data: List[str] = []
else:
dtype = f"d {msg.dlc:x}"
data = [f"{byte:02X}" for byte in msg.data]
arb_id = f"{msg.arbitration_id:X}"
if msg.is_extended_id:
arb_id += "x"
channel = channel2int(msg.channel)
if channel is None:
channel = self.channel
else:
# Many interfaces start channel numbering at 0 which is invalid
channel += 1
if msg.is_fd:
flags = 0
flags |= 1 << 12
if msg.bitrate_switch:
flags |= 1 << 13
if msg.error_state_indicator:
flags |= 1 << 14
serialized = self.FORMAT_MESSAGE_FD.format(
channel=channel,
id=arb_id,
dir="Rx" if msg.is_rx else "Tx",
symbolic_name="",
brs=1 if msg.bitrate_switch else 0,
esi=1 if msg.error_state_indicator else 0,
dlc=len2dlc(msg.dlc),
data_length=len(msg.data),
data=" ".join(data),
message_duration=0,
message_length=0,
flags=flags,
crc=0,
bit_timing_conf_arb=0,
bit_timing_conf_data=0,
bit_timing_conf_ext_arb=0,
bit_timing_conf_ext_data=0,
)
else:
serialized = self.FORMAT_MESSAGE.format(
channel=channel,
id=arb_id,
dir="Rx" if msg.is_rx else "Tx",
dtype=dtype,
data=" ".join(data),
)
self.log_event(serialized, msg.timestamp)