def _replay(pcap_path: str, dst_ip: str, dst_lidar_port: int,
dst_imu_port: int) -> Iterator[bool]:
"""Replay UDP packets out over the network.
Todo:
Not really sure about this interface
Args:
pcap_path: Path to the pcap file to replay
dst_ip: IP to send packets to
dst_lidar_port: Destination port for lidar packets
dst_imu_port: Destination port for imu packets
Returns:
An iterator that reports whether packets were sent successfully as it's
consumed.
"""
pcap_info = _pcap.replay_get_pcap_info(pcap_path, 10000)
pcap_port_guess = _guess_ports(pcap_info)
pcap_handle = _pcap.replay_initialize(pcap_path, dst_ip, dst_ip, {
pcap_port_guess[0]: dst_lidar_port,
pcap_port_guess[1]: dst_imu_port
})
try:
packet_info = _pcap.packet_info()
while _pcap.next_packet_info(pcap_handle, packet_info):
yield _pcap.replay_packet(pcap_handle)
finally:
_pcap.replay_uninitialize(pcap_handle)
yield False
def _pcap_info(path: str) -> Iterator[_pcap.packet_info]:
handle = _pcap.replay_initialize(path)
try:
while True:
if handle is None:
raise ValueError("I/O operation on closed packet source")
packet_info = _pcap.packet_info()
if not _pcap.next_packet_info(handle, packet_info):
break
yield packet_info
finally:
if handle:
_pcap.replay_uninitialize(handle)
def test_read_write_lidar_imu(lidar_packets, imu_packets):
lidar_size = 12608
imu_size = 48
frag_size = 1480
lidar_src_port = 7000
lidar_dst_port = 7001
imu_src_port = 8000
imu_dst_port = 8001
src_address = "127.0.0.1"
dst_address = src_address
lidar_buf = bytearray(lidar_size)
imu_buf = bytearray(imu_size)
tmp_dir = tempfile.mkdtemp()
file_path = os.path.join(tmp_dir, "pcap_test.pcap")
try:
lidar_data, record = write_test_pcap(file_path, lidar_packets,
lidar_size, frag_size,
lidar_src_port, lidar_dst_port)
imu_data, record = write_test_pcap(file_path,
imu_packets,
imu_size,
frag_size,
imu_src_port,
imu_dst_port,
record=record)
_pcap.record_uninitialize(record)
lidar_result = bytearray()
imu_result = bytearray()
pcap_read = _pcap.replay_initialize(file_path, src_address,
dst_address, {})
info = _pcap.packet_info()
while _pcap.next_packet_info(pcap_read, info):
if info.dst_port == imu_dst_port:
_pcap.read_packet(pcap_read, imu_buf)
imu_result += imu_buf
if info.dst_port == lidar_dst_port:
_pcap.read_packet(pcap_read, lidar_buf)
lidar_result += lidar_buf
assert lidar_data == lidar_result
assert imu_data == imu_result
_pcap.replay_uninitialize(pcap_read)
finally:
os.remove(file_path)
os.rmdir(tmp_dir)
def _guess_ports(pcap_path: str) -> Tuple[Optional[int], Optional[int]]:
p = _pcap.replay_initialize(pcap_path)
packet_info = _pcap.packet_info()
loop = True
count = 10000
sizes: Dict[int, Dict[int, int]] = {}
while loop and count > 0:
if not _pcap.next_packet_info(p, packet_info):
loop = False
else:
if packet_info.payload_size not in sizes:
sizes[packet_info.payload_size] = {}
if packet_info.dst_port not in sizes[packet_info.payload_size]:
sizes[packet_info.payload_size][packet_info.dst_port] = 0
sizes[packet_info.payload_size][packet_info.dst_port] += 1
count -= 1
_pcap.replay_uninitialize(p)
return _guess_lidar_port(sizes), _guess_imu_port(sizes)
def __init__(self,
pcap_path: str,
info: SensorInfo,
*,
rate: float = 0.0,
lidar_port: int = 0,
imu_port: int = 0) -> None:
"""Read a single-sensor data stream from a packet capture.
This assumes a pcap contains the packet stream of a single sensor and
attempts to guess which destination ports were associated with lidar vs.
imu data based on packet sizes, unless explicitly specified.
When a rate is specified, output packets in (a multiple of) real time using
the pcap packet capture timestamps.
Args:
info: Sensor metadata
pcap_path: File path of recorded pcap
rate: Output packets in real time, if non-zero
lidar_port: Specify the destination port of lidar packets
imu_port: Specify the destination port of imu packets
Returns:
An iterator of lidar and IMU packets.
"""
pcap_info = _pcap.replay_get_pcap_info(pcap_path, 10000)
lidar_port_guess, imu_port_guess = _guess_ports(pcap_info)
# use guessed values unless ports are specified (0 is falsey)
self._lidar_port = lidar_port or lidar_port_guess
self._imu_port = imu_port or imu_port_guess
self._metadata = info
self._rate = rate
self._handle = _pcap.replay_initialize(pcap_path, "", "", {})
self._lock = Lock()