68 lines
2.3 KiB
Python
68 lines
2.3 KiB
Python
# fixtures: Fixtures with cleanups for testing and convenience.
|
|
#
|
|
# Copyright (C) 2011, Martin Pool <mbp@sourcefrog.net>
|
|
#
|
|
# Licensed under either the Apache License, Version 2.0 or the BSD 3-clause
|
|
# license at the users choice. A copy of both licenses are available in the
|
|
# project source as Apache-2.0 and BSD. You may not use this file except in
|
|
# compliance with one of these two licences.
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under these licenses is distributed on an "AS IS" BASIS, WITHOUT
|
|
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
# license you chose for the specific language governing permissions and
|
|
# limitations under that license.
|
|
|
|
|
|
"""Timeout fixture."""
|
|
|
|
|
|
import signal
|
|
|
|
import fixtures
|
|
|
|
__all__ = [
|
|
'Timeout',
|
|
'TimeoutException',
|
|
]
|
|
|
|
|
|
class TimeoutException(Exception):
|
|
"""Timeout expired"""
|
|
|
|
|
|
class Timeout(fixtures.Fixture):
|
|
"""Fixture that aborts the contained code after a number of seconds.
|
|
|
|
The interrupt can be either gentle, in which case TimeoutException is
|
|
raised, or not gentle, in which case the process will typically be aborted
|
|
by SIGALRM.
|
|
|
|
Cautions:
|
|
* This has no effect on Windows.
|
|
* Only one Timeout can be used at any time per process.
|
|
"""
|
|
|
|
def __init__(self, timeout_secs, gentle):
|
|
self.timeout_secs = timeout_secs
|
|
self.alarm_fn = getattr(signal, 'alarm', None)
|
|
self.gentle = gentle
|
|
|
|
def signal_handler(self, signum, frame):
|
|
raise TimeoutException()
|
|
|
|
def _setUp(self):
|
|
if self.alarm_fn is None:
|
|
return # Can't run on Windows
|
|
if self.gentle:
|
|
# Install a handler for SIGARLM so we can raise an exception rather
|
|
# than the default handler executing, which kills the process.
|
|
old_handler = signal.signal(signal.SIGALRM, self.signal_handler)
|
|
# We add the slarm cleanup before the cleanup for the signal handler,
|
|
# otherwise there is a race condition where the signal handler is
|
|
# cleaned up but the alarm still fires.
|
|
self.addCleanup(lambda: self.alarm_fn(0))
|
|
self.alarm_fn(self.timeout_secs)
|
|
if self.gentle:
|
|
self.addCleanup(lambda: signal.signal(signal.SIGALRM, old_handler))
|