You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

42 lines
1.6 KiB
Python

import sys
import select
from typing import TYPE_CHECKING
from .. import _core, _subprocess
assert (sys.platform != "win32" and sys.platform != "linux") or not TYPE_CHECKING
async def wait_child_exiting(process: "_subprocess.Process") -> None:
kqueue = _core.current_kqueue()
try:
from select import KQ_NOTE_EXIT
except ImportError: # pragma: no cover
# pypy doesn't define KQ_NOTE_EXIT:
# https://bitbucket.org/pypy/pypy/issues/2921/
# I verified this value against both Darwin and FreeBSD
KQ_NOTE_EXIT = 0x80000000
make_event = lambda flags: select.kevent(
process.pid, filter=select.KQ_FILTER_PROC, flags=flags, fflags=KQ_NOTE_EXIT
)
try:
kqueue.control([make_event(select.KQ_EV_ADD | select.KQ_EV_ONESHOT)], 0)
except ProcessLookupError: # pragma: no cover
# This can supposedly happen if the process is in the process
# of exiting, and it can even be the case that kqueue says the
# process doesn't exist before waitpid(WNOHANG) says it hasn't
# exited yet. See the discussion in https://chromium.googlesource.com/
# chromium/src/base/+/master/process/kill_mac.cc .
# We haven't actually seen this error occur since we added
# locking to prevent multiple calls to wait_child_exiting()
# for the same process simultaneously, but given the explanation
# in Chromium it seems we should still keep the check.
return
def abort(_):
kqueue.control([make_event(select.KQ_EV_DELETE)], 0)
return _core.Abort.SUCCEEDED
await _core.wait_kevent(process.pid, select.KQ_FILTER_PROC, abort)