diff --git a/Lib/asyncio/unix_events.py b/Lib/asyncio/unix_events.py index cbbb1065aedad7..d8f653045aee4c 100644 --- a/Lib/asyncio/unix_events.py +++ b/Lib/asyncio/unix_events.py @@ -445,6 +445,7 @@ def __init__(self, loop, pipe, protocol, waiter=None, extra=None): self._fileno = pipe.fileno() self._protocol = protocol self._closing = False + self._paused = False mode = os.fstat(self._fileno).st_mode if not (stat.S_ISFIFO(mode) or @@ -506,10 +507,20 @@ def _read_ready(self): self._loop.call_soon(self._call_connection_lost, None) def pause_reading(self): + if self._closing or self._paused: + return + self._paused = True self._loop._remove_reader(self._fileno) + if self._loop.get_debug(): + logger.debug("%r pauses reading", self) def resume_reading(self): + if self._closing or not self._paused: + return + self._paused = False self._loop._add_reader(self._fileno, self._read_ready) + if self._loop.get_debug(): + logger.debug("%r resumes reading", self) def set_protocol(self, protocol): self._protocol = protocol diff --git a/Lib/test/test_asyncio/test_unix_events.py b/Lib/test/test_asyncio/test_unix_events.py index 02ce7e89da0902..5487b7afef8326 100644 --- a/Lib/test/test_asyncio/test_unix_events.py +++ b/Lib/test/test_asyncio/test_unix_events.py @@ -736,6 +736,7 @@ def test_pause_reading(self, m_read): @mock.patch('os.read') def test_resume_reading(self, m_read): tr = self.read_pipe_transport() + tr.pause_reading() tr.resume_reading() self.loop.assert_reader(5, tr._read_ready) @@ -790,6 +791,32 @@ def test__call_connection_lost_with_err(self): self.assertIsNone(tr._protocol) self.assertIsNone(tr._loop) + def test_pause_reading_on_closed_pipe(self): + tr = self.read_pipe_transport() + tr.close() + test_utils.run_briefly(self.loop) + self.assertIsNone(tr._loop) + tr.pause_reading() + + def test_pause_reading_on_paused_pipe(self): + tr = self.read_pipe_transport() + tr.pause_reading() + # the second call should do nothing + tr.pause_reading() + + def test_resume_reading_on_closed_pipe(self): + tr = self.read_pipe_transport() + tr.close() + test_utils.run_briefly(self.loop) + self.assertIsNone(tr._loop) + tr.resume_reading() + + def test_resume_reading_on_paused_pipe(self): + tr = self.read_pipe_transport() + # the pipe is not paused + # resuming should do nothing + tr.resume_reading() + class UnixWritePipeTransportTests(test_utils.TestCase): diff --git a/Misc/NEWS.d/next/Library/2019-09-29-13-50-24.bpo-38019.6MoOE3.rst b/Misc/NEWS.d/next/Library/2019-09-29-13-50-24.bpo-38019.6MoOE3.rst new file mode 100644 index 00000000000000..aa5a23de24609d --- /dev/null +++ b/Misc/NEWS.d/next/Library/2019-09-29-13-50-24.bpo-38019.6MoOE3.rst @@ -0,0 +1 @@ +Correctly handle pause/resume reading of closed asyncio unix pipe.