45 lines
1.3 KiB
Python
45 lines
1.3 KiB
Python
from contextlib import suppress
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from os import open as osopen
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from os import write, close, O_WRONLY, O_NONBLOCK
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from threading import Thread
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from .terminate_process_on_failure import terminate_process_on_failure
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class PipeReaderThread(Thread):
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eof = b''
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stop_sequence = b'stop_reading\n'
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def __init__(self, pipe_path, stop_event, message_handler):
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super().__init__(daemon=True)
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self._message_handler = message_handler
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self._pipe_path = pipe_path
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self._stop_event = stop_event
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@terminate_process_on_failure
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def run(self):
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with self._open() as pipe:
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while True:
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message = pipe.readline()
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if message == self.stop_sequence:
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self._stop_event.set()
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break
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if message == self.eof:
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self._open().close()
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continue
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self._message_handler(message[:-1])
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def _open(self):
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return open(self._pipe_path, 'rb')
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def stop(self):
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while self.is_alive():
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self._unblock()
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self.join()
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def _unblock(self):
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with suppress(OSError):
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fd = osopen(self._pipe_path, O_WRONLY | O_NONBLOCK)
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write(fd, self.stop_sequence)
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close(fd)
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