diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/test/test_fork1.py | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/Lib/test/test_fork1.py b/Lib/test/test_fork1.py index e036661..88f9fe9 100644 --- a/Lib/test/test_fork1.py +++ b/Lib/test/test_fork1.py @@ -1,8 +1,14 @@ """This test checks for correct fork() behavior. """ +import errno +import imp import os +import signal +import sys import time +import threading + from test.fork_wait import ForkWait from test.support import run_unittest, reap_children, get_attribute @@ -23,6 +29,41 @@ class ForkTest(ForkWait): self.assertEqual(spid, cpid) self.assertEqual(status, 0, "cause = %d, exit = %d" % (status&0xff, status>>8)) + def test_import_lock_fork(self): + 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() + pid = os.fork() + try: + if not pid: + m = __import__(fake_module_name) + if m == complete_module: + os._exit(0) + else: + 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) + finally: + try: + os.kill(pid, signal.SIGKILL) + except OSError: + pass + def test_main(): run_unittest(ForkTest) reap_children() |