def write(self, buf: bytes) -> int:
if self.closed:
raise channel.ChannelClosedException()
channel.channel._debug_log(self, buf, True)
self.serial.write(buf)
return len(buf)
def read(self, n: int, timeout: typing.Optional[float] = None) -> bytes:
if self.closed:
raise channel.ChannelClosedException()
try:
# Block for the first byte only
self.serial.timeout = timeout
first = self.serial.read(1)
if first == b"":
raise TimeoutError()
assert len(
first) == 1, f"Result is longer than expected ({first!r})!"
finally:
self.serial.timeout = 0
remaining = b""
if n > 1:
# If there is more, read it now (non-blocking)
remaining = self.serial.read(min(n, READ_CHUNK_SIZE) - 1)
return channel.channel._debug_log(self, first + remaining, False)
def close(self) -> None:
if self.closed:
raise channel.ChannelClosedException()
self.serial.close()