mirror of
https://github.com/python/cpython.git
synced 2025-09-26 18:29:57 +00:00
Issue #26566: Rewrite test_signal.InterProcessSignalTests
* Add Lib/test/signalinterproctester.py * Don't disable the garbage collector anymore * Don't use os.fork() with a subprocess to not inherit existing signal handlers or threads: start from a fresh process * Don't use UNIX kill command to send a signal but Python os.kill() * Use a timeout of 10 seconds to wait for the signal instead of 1 second * Always use signal.pause(), instead of time.wait(1), to wait for a signal * Use context manager on subprocess.Popen * remove code to retry on EINTR: it's no more needed since the PEP 475 * remove unused function exit_subprocess() * Cleanup the code
This commit is contained in:
Victor Stinner
parent
58f2bd86fb
commit
32eb840a42
2 changed files with 93 additions and 162 deletions
84
Lib/test/signalinterproctester.py
Normal file
84
Lib/test/signalinterproctester.py
Normal file
|
|
@ -0,0 +1,84 @@
|
||||||
|
import os
|
||||||
|
import signal
|
||||||
|
import subprocess
|
||||||
|
import sys
|
||||||
|
import time
|
||||||
|
import unittest
|
||||||
|
|
||||||
|
|
||||||
|
class SIGUSR1Exception(Exception):
|
||||||
|
pass
|
||||||
|
|
||||||
|
|
||||||
|
class InterProcessSignalTests(unittest.TestCase):
|
||||||
|
def setUp(self):
|
||||||
|
self.got_signals = {'SIGHUP': 0, 'SIGUSR1': 0, 'SIGALRM': 0}
|
||||||
|
|
||||||
|
def sighup_handler(self, signum, frame):
|
||||||
|
self.got_signals['SIGHUP'] += 1
|
||||||
|
|
||||||
|
def sigusr1_handler(self, signum, frame):
|
||||||
|
self.got_signals['SIGUSR1'] += 1
|
||||||
|
raise SIGUSR1Exception
|
||||||
|
|
||||||
|
def wait_signal(self, child, signame, exc_class=None):
|
||||||
|
try:
|
||||||
|
if child is not None:
|
||||||
|
# This wait should be interrupted by exc_class
|
||||||
|
# (if set)
|
||||||
|
child.wait()
|
||||||
|
|
||||||
|
timeout = 10.0
|
||||||
|
deadline = time.monotonic() + timeout
|
||||||
|
|
||||||
|
while time.monotonic() < deadline:
|
||||||
|
if self.got_signals[signame]:
|
||||||
|
return
|
||||||
|
signal.pause()
|
||||||
|
except BaseException as exc:
|
||||||
|
if exc_class is not None and isinstance(exc, exc_class):
|
||||||
|
# got the expected exception
|
||||||
|
return
|
||||||
|
raise
|
||||||
|
|
||||||
|
self.fail('signal %s not received after %s seconds'
|
||||||
|
% (signame, timeout))
|
||||||
|
|
||||||
|
def subprocess_send_signal(self, pid, signame):
|
||||||
|
code = 'import os, signal; os.kill(%s, signal.%s)' % (pid, signame)
|
||||||
|
args = [sys.executable, '-I', '-c', code]
|
||||||
|
return subprocess.Popen(args)
|
||||||
|
|
||||||
|
def test_interprocess_signal(self):
|
||||||
|
# Install handlers. This function runs in a sub-process, so we
|
||||||
|
# don't worry about re-setting the default handlers.
|
||||||
|
signal.signal(signal.SIGHUP, self.sighup_handler)
|
||||||
|
signal.signal(signal.SIGUSR1, self.sigusr1_handler)
|
||||||
|
signal.signal(signal.SIGUSR2, signal.SIG_IGN)
|
||||||
|
signal.signal(signal.SIGALRM, signal.default_int_handler)
|
||||||
|
|
||||||
|
# Let the sub-processes know who to send signals to.
|
||||||
|
pid = str(os.getpid())
|
||||||
|
|
||||||
|
with self.subprocess_send_signal(pid, "SIGHUP") as child:
|
||||||
|
self.wait_signal(child, 'SIGHUP')
|
||||||
|
self.assertEqual(self.got_signals, {'SIGHUP': 1, 'SIGUSR1': 0,
|
||||||
|
'SIGALRM': 0})
|
||||||
|
|
||||||
|
with self.subprocess_send_signal(pid, "SIGUSR1") as child:
|
||||||
|
self.wait_signal(child, 'SIGUSR1', SIGUSR1Exception)
|
||||||
|
self.assertEqual(self.got_signals, {'SIGHUP': 1, 'SIGUSR1': 1,
|
||||||
|
'SIGALRM': 0})
|
||||||
|
|
||||||
|
with self.subprocess_send_signal(pid, "SIGUSR2") as child:
|
||||||
|
# Nothing should happen: SIGUSR2 is ignored
|
||||||
|
child.wait()
|
||||||
|
|
||||||
|
signal.alarm(1)
|
||||||
|
self.wait_signal(None, 'SIGALRM', KeyboardInterrupt)
|
||||||
|
self.assertEqual(self.got_signals, {'SIGHUP': 1, 'SIGUSR1': 1,
|
||||||
|
'SIGALRM': 0})
|
||||||
|
|
||||||
|
|
||||||
|
if __name__ == "__main__":
|
||||||
|
unittest.main()
|
||||||
|
|
@ -22,29 +22,6 @@ except ImportError:
|
||||||
_testcapi = None
|
_testcapi = None
|
||||||
|
|
||||||
|
|
||||||
class HandlerBCalled(Exception):
|
|
||||||
pass
|
|
||||||
|
|
||||||
|
|
||||||
def exit_subprocess():
|
|
||||||
"""Use os._exit(0) to exit the current subprocess.
|
|
||||||
|
|
||||||
Otherwise, the test catches the SystemExit and continues executing
|
|
||||||
in parallel with the original test, so you wind up with an
|
|
||||||
exponential number of tests running concurrently.
|
|
||||||
"""
|
|
||||||
os._exit(0)
|
|
||||||
|
|
||||||
|
|
||||||
def ignoring_eintr(__func, *args, **kwargs):
|
|
||||||
try:
|
|
||||||
return __func(*args, **kwargs)
|
|
||||||
except OSError as e:
|
|
||||||
if e.errno != errno.EINTR:
|
|
||||||
raise
|
|
||||||
return None
|
|
||||||
|
|
||||||
|
|
||||||
class GenericTests(unittest.TestCase):
|
class GenericTests(unittest.TestCase):
|
||||||
|
|
||||||
@unittest.skipIf(threading is None, "test needs threading module")
|
@unittest.skipIf(threading is None, "test needs threading module")
|
||||||
|
|
@ -62,145 +39,6 @@ class GenericTests(unittest.TestCase):
|
||||||
self.assertEqual(sys.platform, "win32")
|
self.assertEqual(sys.platform, "win32")
|
||||||
|
|
||||||
|
|
||||||
@unittest.skipIf(sys.platform == "win32", "Not valid on Windows")
|
|
||||||
class InterProcessSignalTests(unittest.TestCase):
|
|
||||||
MAX_DURATION = 20 # Entire test should last at most 20 sec.
|
|
||||||
|
|
||||||
def setUp(self):
|
|
||||||
self.using_gc = gc.isenabled()
|
|
||||||
gc.disable()
|
|
||||||
|
|
||||||
def tearDown(self):
|
|
||||||
if self.using_gc:
|
|
||||||
gc.enable()
|
|
||||||
|
|
||||||
def format_frame(self, frame, limit=None):
|
|
||||||
return ''.join(traceback.format_stack(frame, limit=limit))
|
|
||||||
|
|
||||||
def handlerA(self, signum, frame):
|
|
||||||
self.a_called = True
|
|
||||||
|
|
||||||
def handlerB(self, signum, frame):
|
|
||||||
self.b_called = True
|
|
||||||
raise HandlerBCalled(signum, self.format_frame(frame))
|
|
||||||
|
|
||||||
def wait(self, child):
|
|
||||||
"""Wait for child to finish, ignoring EINTR."""
|
|
||||||
while True:
|
|
||||||
try:
|
|
||||||
child.wait()
|
|
||||||
return
|
|
||||||
except OSError as e:
|
|
||||||
if e.errno != errno.EINTR:
|
|
||||||
raise
|
|
||||||
|
|
||||||
def run_test(self):
|
|
||||||
# Install handlers. This function runs in a sub-process, so we
|
|
||||||
# don't worry about re-setting the default handlers.
|
|
||||||
signal.signal(signal.SIGHUP, self.handlerA)
|
|
||||||
signal.signal(signal.SIGUSR1, self.handlerB)
|
|
||||||
signal.signal(signal.SIGUSR2, signal.SIG_IGN)
|
|
||||||
signal.signal(signal.SIGALRM, signal.default_int_handler)
|
|
||||||
|
|
||||||
# Variables the signals will modify:
|
|
||||||
self.a_called = False
|
|
||||||
self.b_called = False
|
|
||||||
|
|
||||||
# Let the sub-processes know who to send signals to.
|
|
||||||
pid = os.getpid()
|
|
||||||
|
|
||||||
child = ignoring_eintr(subprocess.Popen, ['kill', '-HUP', str(pid)])
|
|
||||||
if child:
|
|
||||||
self.wait(child)
|
|
||||||
if not self.a_called:
|
|
||||||
time.sleep(1) # Give the signal time to be delivered.
|
|
||||||
self.assertTrue(self.a_called)
|
|
||||||
self.assertFalse(self.b_called)
|
|
||||||
self.a_called = False
|
|
||||||
|
|
||||||
# Make sure the signal isn't delivered while the previous
|
|
||||||
# Popen object is being destroyed, because __del__ swallows
|
|
||||||
# exceptions.
|
|
||||||
del child
|
|
||||||
try:
|
|
||||||
child = subprocess.Popen(['kill', '-USR1', str(pid)])
|
|
||||||
# This wait should be interrupted by the signal's exception.
|
|
||||||
self.wait(child)
|
|
||||||
time.sleep(1) # Give the signal time to be delivered.
|
|
||||||
self.fail('HandlerBCalled exception not raised')
|
|
||||||
except HandlerBCalled:
|
|
||||||
self.assertTrue(self.b_called)
|
|
||||||
self.assertFalse(self.a_called)
|
|
||||||
|
|
||||||
child = ignoring_eintr(subprocess.Popen, ['kill', '-USR2', str(pid)])
|
|
||||||
if child:
|
|
||||||
self.wait(child) # Nothing should happen.
|
|
||||||
|
|
||||||
try:
|
|
||||||
signal.alarm(1)
|
|
||||||
# The race condition in pause doesn't matter in this case,
|
|
||||||
# since alarm is going to raise a KeyboardException, which
|
|
||||||
# will skip the call.
|
|
||||||
signal.pause()
|
|
||||||
# But if another signal arrives before the alarm, pause
|
|
||||||
# may return early.
|
|
||||||
time.sleep(1)
|
|
||||||
except KeyboardInterrupt:
|
|
||||||
pass
|
|
||||||
except:
|
|
||||||
self.fail("Some other exception woke us from pause: %s" %
|
|
||||||
traceback.format_exc())
|
|
||||||
else:
|
|
||||||
self.fail("pause returned of its own accord, and the signal"
|
|
||||||
" didn't arrive after another second.")
|
|
||||||
|
|
||||||
# Issue 3864, unknown if this affects earlier versions of freebsd also
|
|
||||||
@unittest.skipIf(sys.platform=='freebsd6',
|
|
||||||
'inter process signals not reliable (do not mix well with threading) '
|
|
||||||
'on freebsd6')
|
|
||||||
def test_main(self):
|
|
||||||
# This function spawns a child process to insulate the main
|
|
||||||
# test-running process from all the signals. It then
|
|
||||||
# communicates with that child process over a pipe and
|
|
||||||
# re-raises information about any exceptions the child
|
|
||||||
# raises. The real work happens in self.run_test().
|
|
||||||
os_done_r, os_done_w = os.pipe()
|
|
||||||
with closing(os.fdopen(os_done_r, 'rb')) as done_r, \
|
|
||||||
closing(os.fdopen(os_done_w, 'wb')) as done_w:
|
|
||||||
child = os.fork()
|
|
||||||
if child == 0:
|
|
||||||
# In the child process; run the test and report results
|
|
||||||
# through the pipe.
|
|
||||||
try:
|
|
||||||
done_r.close()
|
|
||||||
# Have to close done_w again here because
|
|
||||||
# exit_subprocess() will skip the enclosing with block.
|
|
||||||
with closing(done_w):
|
|
||||||
try:
|
|
||||||
self.run_test()
|
|
||||||
except:
|
|
||||||
pickle.dump(traceback.format_exc(), done_w)
|
|
||||||
else:
|
|
||||||
pickle.dump(None, done_w)
|
|
||||||
except:
|
|
||||||
print('Uh oh, raised from pickle.')
|
|
||||||
traceback.print_exc()
|
|
||||||
finally:
|
|
||||||
exit_subprocess()
|
|
||||||
|
|
||||||
done_w.close()
|
|
||||||
# Block for up to MAX_DURATION seconds for the test to finish.
|
|
||||||
r, w, x = select.select([done_r], [], [], self.MAX_DURATION)
|
|
||||||
if done_r in r:
|
|
||||||
tb = pickle.load(done_r)
|
|
||||||
if tb:
|
|
||||||
self.fail(tb)
|
|
||||||
else:
|
|
||||||
os.kill(child, signal.SIGKILL)
|
|
||||||
self.fail('Test deadlocked after %d seconds.' %
|
|
||||||
self.MAX_DURATION)
|
|
||||||
|
|
||||||
|
|
||||||
@unittest.skipIf(sys.platform == "win32", "Not valid on Windows")
|
@unittest.skipIf(sys.platform == "win32", "Not valid on Windows")
|
||||||
class PosixTests(unittest.TestCase):
|
class PosixTests(unittest.TestCase):
|
||||||
def trivial_signal_handler(self, *args):
|
def trivial_signal_handler(self, *args):
|
||||||
|
|
@ -224,6 +62,15 @@ class PosixTests(unittest.TestCase):
|
||||||
signal.signal(signal.SIGHUP, hup)
|
signal.signal(signal.SIGHUP, hup)
|
||||||
self.assertEqual(signal.getsignal(signal.SIGHUP), hup)
|
self.assertEqual(signal.getsignal(signal.SIGHUP), hup)
|
||||||
|
|
||||||
|
# Issue 3864, unknown if this affects earlier versions of freebsd also
|
||||||
|
@unittest.skipIf(sys.platform=='freebsd6',
|
||||||
|
'inter process signals not reliable (do not mix well with threading) '
|
||||||
|
'on freebsd6')
|
||||||
|
def test_interprocess_signal(self):
|
||||||
|
dirname = os.path.dirname(__file__)
|
||||||
|
script = os.path.join(dirname, 'signalinterproctester.py')
|
||||||
|
assert_python_ok(script)
|
||||||
|
|
||||||
|
|
||||||
@unittest.skipUnless(sys.platform == "win32", "Windows specific")
|
@unittest.skipUnless(sys.platform == "win32", "Windows specific")
|
||||||
class WindowsSignalTests(unittest.TestCase):
|
class WindowsSignalTests(unittest.TestCase):
|
||||||
|
|
|
||||||
Loading…
Add table
Add a link
Reference in a new issue