mirror of
https://github.com/python/cpython.git
synced 2025-10-19 16:03:42 +00:00
fd8f42d3d1
Don't ignore errors raised by `PyErr_WarnFormat` in `warn_about_fork_with_threads` Instead, ignore the warnings in all test code that forks. (That's a lot of functions.) In `test_support`, make `ignore_warnings` a context manager (as well as decorator), and add a `message` argument to it. Also add a `ignore_fork_in_thread_deprecation_warnings` helper for the deadlock-in-fork warning.
104 lines
3.5 KiB
Python
104 lines
3.5 KiB
Python
"""This test checks for correct fork() behavior.
|
|
"""
|
|
|
|
import _imp as imp
|
|
import os
|
|
import signal
|
|
import sys
|
|
import threading
|
|
import time
|
|
import unittest
|
|
|
|
from test.fork_wait import ForkWait
|
|
from test import support
|
|
from test.support import warnings_helper
|
|
|
|
|
|
# Skip test if fork does not exist.
|
|
if not support.has_fork_support:
|
|
raise unittest.SkipTest("test module requires working os.fork")
|
|
|
|
|
|
class ForkTest(ForkWait):
|
|
@warnings_helper.ignore_fork_in_thread_deprecation_warnings()
|
|
def test_threaded_import_lock_fork(self):
|
|
"""Check fork() in main thread works while a subthread is doing an import"""
|
|
import_started = threading.Event()
|
|
fake_module_name = "fake test module"
|
|
partial_module = "partial"
|
|
complete_module = "complete"
|
|
def importer():
|
|
imp.acquire_lock()
|
|
sys.modules[fake_module_name] = partial_module
|
|
import_started.set()
|
|
time.sleep(0.01) # Give the other thread time to try and acquire.
|
|
sys.modules[fake_module_name] = complete_module
|
|
imp.release_lock()
|
|
t = threading.Thread(target=importer)
|
|
t.start()
|
|
import_started.wait()
|
|
exitcode = 42
|
|
pid = os.fork()
|
|
try:
|
|
# PyOS_BeforeFork should have waited for the import to complete
|
|
# before forking, so the child can recreate the import lock
|
|
# correctly, but also won't see a partially initialised module
|
|
if not pid:
|
|
m = __import__(fake_module_name)
|
|
if m == complete_module:
|
|
os._exit(exitcode)
|
|
else:
|
|
if support.verbose > 1:
|
|
print("Child encountered partial module")
|
|
os._exit(1)
|
|
else:
|
|
t.join()
|
|
# Exitcode 1 means the child got a partial module (bad.) No
|
|
# exitcode (but a hang, which manifests as 'got pid 0')
|
|
# means the child deadlocked (also bad.)
|
|
self.wait_impl(pid, exitcode=exitcode)
|
|
finally:
|
|
try:
|
|
os.kill(pid, signal.SIGKILL)
|
|
except OSError:
|
|
pass
|
|
|
|
@warnings_helper.ignore_fork_in_thread_deprecation_warnings()
|
|
def test_nested_import_lock_fork(self):
|
|
"""Check fork() in main thread works while the main thread is doing an import"""
|
|
exitcode = 42
|
|
# Issue 9573: this used to trigger RuntimeError in the child process
|
|
def fork_with_import_lock(level):
|
|
release = 0
|
|
in_child = False
|
|
try:
|
|
try:
|
|
for i in range(level):
|
|
imp.acquire_lock()
|
|
release += 1
|
|
pid = os.fork()
|
|
in_child = not pid
|
|
finally:
|
|
for i in range(release):
|
|
imp.release_lock()
|
|
except RuntimeError:
|
|
if in_child:
|
|
if support.verbose > 1:
|
|
print("RuntimeError in child")
|
|
os._exit(1)
|
|
raise
|
|
if in_child:
|
|
os._exit(exitcode)
|
|
self.wait_impl(pid, exitcode=exitcode)
|
|
|
|
# Check this works with various levels of nested
|
|
# import in the main thread
|
|
for level in range(5):
|
|
fork_with_import_lock(level)
|
|
|
|
|
|
def tearDownModule():
|
|
support.reap_children()
|
|
|
|
if __name__ == "__main__":
|
|
unittest.main()
|