bpo-40550: Fix time-of-check/time-of-action issue in subprocess.Popen.send_signal. (GH-20010)
send_signal() now swallows the exception if the process it thought was still alive winds up not to exist anymore (always a plausible race condition despite the checks). Co-authored-by: Gregory P. Smith <greg@krypto.org>
This commit is contained in:
parent
31729366e2
commit
01a202ab6b
|
@ -2078,7 +2078,11 @@ class Popen(object):
|
|||
# The race condition can still happen if the race condition
|
||||
# described above happens between the returncode test
|
||||
# and the kill() call.
|
||||
os.kill(self.pid, sig)
|
||||
try:
|
||||
os.kill(self.pid, sig)
|
||||
except ProcessLookupError:
|
||||
# Supress the race condition error; bpo-40550.
|
||||
pass
|
||||
|
||||
def terminate(self):
|
||||
"""Terminate the process with SIGTERM
|
||||
|
|
|
@ -3229,6 +3229,19 @@ class POSIXProcessTestCase(BaseTestCase):
|
|||
# so Popen failed to read it and uses a default returncode instead.
|
||||
self.assertIsNotNone(proc.returncode)
|
||||
|
||||
def test_send_signal_race2(self):
|
||||
# bpo-40550: the process might exist between the returncode check and
|
||||
# the kill operation
|
||||
p = subprocess.Popen([sys.executable, '-c', 'exit(1)'])
|
||||
|
||||
# wait for process to exit
|
||||
while not p.returncode:
|
||||
p.poll()
|
||||
|
||||
with mock.patch.object(p, 'poll', new=lambda: None):
|
||||
p.returncode = None
|
||||
p.send_signal(signal.SIGTERM)
|
||||
|
||||
def test_communicate_repeated_call_after_stdout_close(self):
|
||||
proc = subprocess.Popen([sys.executable, '-c',
|
||||
'import os, time; os.close(1), time.sleep(2)'],
|
||||
|
|
|
@ -0,0 +1 @@
|
|||
Fix time-of-check/time-of-action issue in subprocess.Popen.send_signal.
|
Loading…
Reference in New Issue