934 lines
34 KiB
Python
934 lines
34 KiB
Python
# Very rudimentary test of threading module
|
|
|
|
import test.test_support
|
|
from test.test_support import verbose, cpython_only
|
|
from test.script_helper import assert_python_ok
|
|
|
|
import random
|
|
import re
|
|
import sys
|
|
thread = test.test_support.import_module('thread')
|
|
threading = test.test_support.import_module('threading')
|
|
import time
|
|
import unittest
|
|
import weakref
|
|
import os
|
|
import subprocess
|
|
try:
|
|
import _testcapi
|
|
except ImportError:
|
|
_testcapi = None
|
|
|
|
from test import lock_tests
|
|
|
|
# A trivial mutable counter.
|
|
class Counter(object):
|
|
def __init__(self):
|
|
self.value = 0
|
|
def inc(self):
|
|
self.value += 1
|
|
def dec(self):
|
|
self.value -= 1
|
|
def get(self):
|
|
return self.value
|
|
|
|
class TestThread(threading.Thread):
|
|
def __init__(self, name, testcase, sema, mutex, nrunning):
|
|
threading.Thread.__init__(self, name=name)
|
|
self.testcase = testcase
|
|
self.sema = sema
|
|
self.mutex = mutex
|
|
self.nrunning = nrunning
|
|
|
|
def run(self):
|
|
delay = random.random() / 10000.0
|
|
if verbose:
|
|
print 'task %s will run for %.1f usec' % (
|
|
self.name, delay * 1e6)
|
|
|
|
with self.sema:
|
|
with self.mutex:
|
|
self.nrunning.inc()
|
|
if verbose:
|
|
print self.nrunning.get(), 'tasks are running'
|
|
self.testcase.assertTrue(self.nrunning.get() <= 3)
|
|
|
|
time.sleep(delay)
|
|
if verbose:
|
|
print 'task', self.name, 'done'
|
|
|
|
with self.mutex:
|
|
self.nrunning.dec()
|
|
self.testcase.assertTrue(self.nrunning.get() >= 0)
|
|
if verbose:
|
|
print '%s is finished. %d tasks are running' % (
|
|
self.name, self.nrunning.get())
|
|
|
|
class BaseTestCase(unittest.TestCase):
|
|
def setUp(self):
|
|
self._threads = test.test_support.threading_setup()
|
|
|
|
def tearDown(self):
|
|
test.test_support.threading_cleanup(*self._threads)
|
|
test.test_support.reap_children()
|
|
|
|
|
|
class ThreadTests(BaseTestCase):
|
|
|
|
# Create a bunch of threads, let each do some work, wait until all are
|
|
# done.
|
|
def test_various_ops(self):
|
|
# This takes about n/3 seconds to run (about n/3 clumps of tasks,
|
|
# times about 1 second per clump).
|
|
NUMTASKS = 10
|
|
|
|
# no more than 3 of the 10 can run at once
|
|
sema = threading.BoundedSemaphore(value=3)
|
|
mutex = threading.RLock()
|
|
numrunning = Counter()
|
|
|
|
threads = []
|
|
|
|
for i in range(NUMTASKS):
|
|
t = TestThread("<thread %d>"%i, self, sema, mutex, numrunning)
|
|
threads.append(t)
|
|
self.assertEqual(t.ident, None)
|
|
self.assertTrue(re.match('<TestThread\(.*, initial\)>', repr(t)))
|
|
t.start()
|
|
|
|
if verbose:
|
|
print 'waiting for all tasks to complete'
|
|
for t in threads:
|
|
t.join(NUMTASKS)
|
|
self.assertTrue(not t.is_alive())
|
|
self.assertNotEqual(t.ident, 0)
|
|
self.assertFalse(t.ident is None)
|
|
self.assertTrue(re.match('<TestThread\(.*, \w+ -?\d+\)>', repr(t)))
|
|
if verbose:
|
|
print 'all tasks done'
|
|
self.assertEqual(numrunning.get(), 0)
|
|
|
|
def test_ident_of_no_threading_threads(self):
|
|
# The ident still must work for the main thread and dummy threads.
|
|
self.assertFalse(threading.currentThread().ident is None)
|
|
def f():
|
|
ident.append(threading.currentThread().ident)
|
|
done.set()
|
|
done = threading.Event()
|
|
ident = []
|
|
thread.start_new_thread(f, ())
|
|
done.wait()
|
|
self.assertFalse(ident[0] is None)
|
|
# Kill the "immortal" _DummyThread
|
|
del threading._active[ident[0]]
|
|
|
|
# run with a small(ish) thread stack size (256kB)
|
|
def test_various_ops_small_stack(self):
|
|
if verbose:
|
|
print 'with 256kB thread stack size...'
|
|
try:
|
|
threading.stack_size(262144)
|
|
except thread.error:
|
|
self.skipTest('platform does not support changing thread stack size')
|
|
self.test_various_ops()
|
|
threading.stack_size(0)
|
|
|
|
# run with a large thread stack size (1MB)
|
|
def test_various_ops_large_stack(self):
|
|
if verbose:
|
|
print 'with 1MB thread stack size...'
|
|
try:
|
|
threading.stack_size(0x100000)
|
|
except thread.error:
|
|
self.skipTest('platform does not support changing thread stack size')
|
|
self.test_various_ops()
|
|
threading.stack_size(0)
|
|
|
|
def test_foreign_thread(self):
|
|
# Check that a "foreign" thread can use the threading module.
|
|
def f(mutex):
|
|
# Calling current_thread() forces an entry for the foreign
|
|
# thread to get made in the threading._active map.
|
|
threading.current_thread()
|
|
mutex.release()
|
|
|
|
mutex = threading.Lock()
|
|
mutex.acquire()
|
|
tid = thread.start_new_thread(f, (mutex,))
|
|
# Wait for the thread to finish.
|
|
mutex.acquire()
|
|
self.assertIn(tid, threading._active)
|
|
self.assertIsInstance(threading._active[tid], threading._DummyThread)
|
|
del threading._active[tid]
|
|
|
|
# PyThreadState_SetAsyncExc() is a CPython-only gimmick, not (currently)
|
|
# exposed at the Python level. This test relies on ctypes to get at it.
|
|
def test_PyThreadState_SetAsyncExc(self):
|
|
try:
|
|
import ctypes
|
|
except ImportError:
|
|
self.skipTest('requires ctypes')
|
|
|
|
set_async_exc = ctypes.pythonapi.PyThreadState_SetAsyncExc
|
|
|
|
class AsyncExc(Exception):
|
|
pass
|
|
|
|
exception = ctypes.py_object(AsyncExc)
|
|
|
|
# First check it works when setting the exception from the same thread.
|
|
tid = thread.get_ident()
|
|
|
|
try:
|
|
result = set_async_exc(ctypes.c_long(tid), exception)
|
|
# The exception is async, so we might have to keep the VM busy until
|
|
# it notices.
|
|
while True:
|
|
pass
|
|
except AsyncExc:
|
|
pass
|
|
else:
|
|
# This code is unreachable but it reflects the intent. If we wanted
|
|
# to be smarter the above loop wouldn't be infinite.
|
|
self.fail("AsyncExc not raised")
|
|
try:
|
|
self.assertEqual(result, 1) # one thread state modified
|
|
except UnboundLocalError:
|
|
# The exception was raised too quickly for us to get the result.
|
|
pass
|
|
|
|
# `worker_started` is set by the thread when it's inside a try/except
|
|
# block waiting to catch the asynchronously set AsyncExc exception.
|
|
# `worker_saw_exception` is set by the thread upon catching that
|
|
# exception.
|
|
worker_started = threading.Event()
|
|
worker_saw_exception = threading.Event()
|
|
|
|
class Worker(threading.Thread):
|
|
def run(self):
|
|
self.id = thread.get_ident()
|
|
self.finished = False
|
|
|
|
try:
|
|
while True:
|
|
worker_started.set()
|
|
time.sleep(0.1)
|
|
except AsyncExc:
|
|
self.finished = True
|
|
worker_saw_exception.set()
|
|
|
|
t = Worker()
|
|
t.daemon = True # so if this fails, we don't hang Python at shutdown
|
|
t.start()
|
|
if verbose:
|
|
print " started worker thread"
|
|
|
|
# Try a thread id that doesn't make sense.
|
|
if verbose:
|
|
print " trying nonsensical thread id"
|
|
result = set_async_exc(ctypes.c_long(-1), exception)
|
|
self.assertEqual(result, 0) # no thread states modified
|
|
|
|
# Now raise an exception in the worker thread.
|
|
if verbose:
|
|
print " waiting for worker thread to get started"
|
|
ret = worker_started.wait()
|
|
self.assertTrue(ret)
|
|
if verbose:
|
|
print " verifying worker hasn't exited"
|
|
self.assertTrue(not t.finished)
|
|
if verbose:
|
|
print " attempting to raise asynch exception in worker"
|
|
result = set_async_exc(ctypes.c_long(t.id), exception)
|
|
self.assertEqual(result, 1) # one thread state modified
|
|
if verbose:
|
|
print " waiting for worker to say it caught the exception"
|
|
worker_saw_exception.wait(timeout=10)
|
|
self.assertTrue(t.finished)
|
|
if verbose:
|
|
print " all OK -- joining worker"
|
|
if t.finished:
|
|
t.join()
|
|
# else the thread is still running, and we have no way to kill it
|
|
|
|
def test_limbo_cleanup(self):
|
|
# Issue 7481: Failure to start thread should cleanup the limbo map.
|
|
def fail_new_thread(*args):
|
|
raise thread.error()
|
|
_start_new_thread = threading._start_new_thread
|
|
threading._start_new_thread = fail_new_thread
|
|
try:
|
|
t = threading.Thread(target=lambda: None)
|
|
self.assertRaises(thread.error, t.start)
|
|
self.assertFalse(
|
|
t in threading._limbo,
|
|
"Failed to cleanup _limbo map on failure of Thread.start().")
|
|
finally:
|
|
threading._start_new_thread = _start_new_thread
|
|
|
|
def test_finalize_runnning_thread(self):
|
|
# Issue 1402: the PyGILState_Ensure / _Release functions may be called
|
|
# very late on python exit: on deallocation of a running thread for
|
|
# example.
|
|
try:
|
|
import ctypes
|
|
except ImportError:
|
|
self.skipTest('requires ctypes')
|
|
|
|
rc = subprocess.call([sys.executable, "-c", """if 1:
|
|
import ctypes, sys, time, thread
|
|
|
|
# This lock is used as a simple event variable.
|
|
ready = thread.allocate_lock()
|
|
ready.acquire()
|
|
|
|
# Module globals are cleared before __del__ is run
|
|
# So we save the functions in class dict
|
|
class C:
|
|
ensure = ctypes.pythonapi.PyGILState_Ensure
|
|
release = ctypes.pythonapi.PyGILState_Release
|
|
def __del__(self):
|
|
state = self.ensure()
|
|
self.release(state)
|
|
|
|
def waitingThread():
|
|
x = C()
|
|
ready.release()
|
|
time.sleep(100)
|
|
|
|
thread.start_new_thread(waitingThread, ())
|
|
ready.acquire() # Be sure the other thread is waiting.
|
|
sys.exit(42)
|
|
"""])
|
|
self.assertEqual(rc, 42)
|
|
|
|
def test_finalize_with_trace(self):
|
|
# Issue1733757
|
|
# Avoid a deadlock when sys.settrace steps into threading._shutdown
|
|
p = subprocess.Popen([sys.executable, "-c", """if 1:
|
|
import sys, threading
|
|
|
|
# A deadlock-killer, to prevent the
|
|
# testsuite to hang forever
|
|
def killer():
|
|
import os, time
|
|
time.sleep(2)
|
|
print 'program blocked; aborting'
|
|
os._exit(2)
|
|
t = threading.Thread(target=killer)
|
|
t.daemon = True
|
|
t.start()
|
|
|
|
# This is the trace function
|
|
def func(frame, event, arg):
|
|
threading.current_thread()
|
|
return func
|
|
|
|
sys.settrace(func)
|
|
"""],
|
|
stdout=subprocess.PIPE,
|
|
stderr=subprocess.PIPE)
|
|
self.addCleanup(p.stdout.close)
|
|
self.addCleanup(p.stderr.close)
|
|
stdout, stderr = p.communicate()
|
|
rc = p.returncode
|
|
self.assertFalse(rc == 2, "interpreted was blocked")
|
|
self.assertTrue(rc == 0,
|
|
"Unexpected error: " + repr(stderr))
|
|
|
|
def test_join_nondaemon_on_shutdown(self):
|
|
# Issue 1722344
|
|
# Raising SystemExit skipped threading._shutdown
|
|
p = subprocess.Popen([sys.executable, "-c", """if 1:
|
|
import threading
|
|
from time import sleep
|
|
|
|
def child():
|
|
sleep(1)
|
|
# As a non-daemon thread we SHOULD wake up and nothing
|
|
# should be torn down yet
|
|
print "Woke up, sleep function is:", sleep
|
|
|
|
threading.Thread(target=child).start()
|
|
raise SystemExit
|
|
"""],
|
|
stdout=subprocess.PIPE,
|
|
stderr=subprocess.PIPE)
|
|
self.addCleanup(p.stdout.close)
|
|
self.addCleanup(p.stderr.close)
|
|
stdout, stderr = p.communicate()
|
|
self.assertEqual(stdout.strip(),
|
|
"Woke up, sleep function is: <built-in function sleep>")
|
|
stderr = re.sub(r"^\[\d+ refs\]", "", stderr, re.MULTILINE).strip()
|
|
self.assertEqual(stderr, "")
|
|
|
|
def test_enumerate_after_join(self):
|
|
# Try hard to trigger #1703448: a thread is still returned in
|
|
# threading.enumerate() after it has been join()ed.
|
|
enum = threading.enumerate
|
|
old_interval = sys.getcheckinterval()
|
|
try:
|
|
for i in xrange(1, 100):
|
|
# Try a couple times at each thread-switching interval
|
|
# to get more interleavings.
|
|
sys.setcheckinterval(i // 5)
|
|
t = threading.Thread(target=lambda: None)
|
|
t.start()
|
|
t.join()
|
|
l = enum()
|
|
self.assertNotIn(t, l,
|
|
"#1703448 triggered after %d trials: %s" % (i, l))
|
|
finally:
|
|
sys.setcheckinterval(old_interval)
|
|
|
|
def test_no_refcycle_through_target(self):
|
|
class RunSelfFunction(object):
|
|
def __init__(self, should_raise):
|
|
# The links in this refcycle from Thread back to self
|
|
# should be cleaned up when the thread completes.
|
|
self.should_raise = should_raise
|
|
self.thread = threading.Thread(target=self._run,
|
|
args=(self,),
|
|
kwargs={'yet_another':self})
|
|
self.thread.start()
|
|
|
|
def _run(self, other_ref, yet_another):
|
|
if self.should_raise:
|
|
raise SystemExit
|
|
|
|
cyclic_object = RunSelfFunction(should_raise=False)
|
|
weak_cyclic_object = weakref.ref(cyclic_object)
|
|
cyclic_object.thread.join()
|
|
del cyclic_object
|
|
self.assertEqual(None, weak_cyclic_object(),
|
|
msg=('%d references still around' %
|
|
sys.getrefcount(weak_cyclic_object())))
|
|
|
|
raising_cyclic_object = RunSelfFunction(should_raise=True)
|
|
weak_raising_cyclic_object = weakref.ref(raising_cyclic_object)
|
|
raising_cyclic_object.thread.join()
|
|
del raising_cyclic_object
|
|
self.assertEqual(None, weak_raising_cyclic_object(),
|
|
msg=('%d references still around' %
|
|
sys.getrefcount(weak_raising_cyclic_object())))
|
|
|
|
@unittest.skipUnless(hasattr(os, 'fork'), 'test needs fork()')
|
|
def test_dummy_thread_after_fork(self):
|
|
# Issue #14308: a dummy thread in the active list doesn't mess up
|
|
# the after-fork mechanism.
|
|
code = """if 1:
|
|
import thread, threading, os, time
|
|
|
|
def background_thread(evt):
|
|
# Creates and registers the _DummyThread instance
|
|
threading.current_thread()
|
|
evt.set()
|
|
time.sleep(10)
|
|
|
|
evt = threading.Event()
|
|
thread.start_new_thread(background_thread, (evt,))
|
|
evt.wait()
|
|
assert threading.active_count() == 2, threading.active_count()
|
|
if os.fork() == 0:
|
|
assert threading.active_count() == 1, threading.active_count()
|
|
os._exit(0)
|
|
else:
|
|
os.wait()
|
|
"""
|
|
_, out, err = assert_python_ok("-c", code)
|
|
self.assertEqual(out, '')
|
|
self.assertEqual(err, '')
|
|
|
|
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
|
|
def test_is_alive_after_fork(self):
|
|
# Try hard to trigger #18418: is_alive() could sometimes be True on
|
|
# threads that vanished after a fork.
|
|
old_interval = sys.getcheckinterval()
|
|
|
|
# Make the bug more likely to manifest.
|
|
sys.setcheckinterval(10)
|
|
|
|
try:
|
|
for i in range(20):
|
|
t = threading.Thread(target=lambda: None)
|
|
t.start()
|
|
pid = os.fork()
|
|
if pid == 0:
|
|
os._exit(1 if t.is_alive() else 0)
|
|
else:
|
|
t.join()
|
|
pid, status = os.waitpid(pid, 0)
|
|
self.assertEqual(0, status)
|
|
finally:
|
|
sys.setcheckinterval(old_interval)
|
|
|
|
def test_BoundedSemaphore_limit(self):
|
|
# BoundedSemaphore should raise ValueError if released too often.
|
|
for limit in range(1, 10):
|
|
bs = threading.BoundedSemaphore(limit)
|
|
threads = [threading.Thread(target=bs.acquire)
|
|
for _ in range(limit)]
|
|
for t in threads:
|
|
t.start()
|
|
for t in threads:
|
|
t.join()
|
|
threads = [threading.Thread(target=bs.release)
|
|
for _ in range(limit)]
|
|
for t in threads:
|
|
t.start()
|
|
for t in threads:
|
|
t.join()
|
|
self.assertRaises(ValueError, bs.release)
|
|
|
|
class ThreadJoinOnShutdown(BaseTestCase):
|
|
|
|
# Between fork() and exec(), only async-safe functions are allowed (issues
|
|
# #12316 and #11870), and fork() from a worker thread is known to trigger
|
|
# problems with some operating systems (issue #3863): skip problematic tests
|
|
# on platforms known to behave badly.
|
|
platforms_to_skip = ('freebsd4', 'freebsd5', 'freebsd6', 'netbsd5',
|
|
'os2emx')
|
|
|
|
def _run_and_join(self, script):
|
|
script = """if 1:
|
|
import sys, os, time, threading
|
|
|
|
# a thread, which waits for the main program to terminate
|
|
def joiningfunc(mainthread):
|
|
mainthread.join()
|
|
print 'end of thread'
|
|
\n""" + script
|
|
|
|
p = subprocess.Popen([sys.executable, "-c", script], stdout=subprocess.PIPE)
|
|
rc = p.wait()
|
|
data = p.stdout.read().replace('\r', '')
|
|
p.stdout.close()
|
|
self.assertEqual(data, "end of main\nend of thread\n")
|
|
self.assertFalse(rc == 2, "interpreter was blocked")
|
|
self.assertTrue(rc == 0, "Unexpected error")
|
|
|
|
def test_1_join_on_shutdown(self):
|
|
# The usual case: on exit, wait for a non-daemon thread
|
|
script = """if 1:
|
|
import os
|
|
t = threading.Thread(target=joiningfunc,
|
|
args=(threading.current_thread(),))
|
|
t.start()
|
|
time.sleep(0.1)
|
|
print 'end of main'
|
|
"""
|
|
self._run_and_join(script)
|
|
|
|
|
|
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
|
|
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
|
|
def test_2_join_in_forked_process(self):
|
|
# Like the test above, but from a forked interpreter
|
|
script = """if 1:
|
|
childpid = os.fork()
|
|
if childpid != 0:
|
|
os.waitpid(childpid, 0)
|
|
sys.exit(0)
|
|
|
|
t = threading.Thread(target=joiningfunc,
|
|
args=(threading.current_thread(),))
|
|
t.start()
|
|
print 'end of main'
|
|
"""
|
|
self._run_and_join(script)
|
|
|
|
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
|
|
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
|
|
def test_3_join_in_forked_from_thread(self):
|
|
# Like the test above, but fork() was called from a worker thread
|
|
# In the forked process, the main Thread object must be marked as stopped.
|
|
script = """if 1:
|
|
main_thread = threading.current_thread()
|
|
def worker():
|
|
childpid = os.fork()
|
|
if childpid != 0:
|
|
os.waitpid(childpid, 0)
|
|
sys.exit(0)
|
|
|
|
t = threading.Thread(target=joiningfunc,
|
|
args=(main_thread,))
|
|
print 'end of main'
|
|
t.start()
|
|
t.join() # Should not block: main_thread is already stopped
|
|
|
|
w = threading.Thread(target=worker)
|
|
w.start()
|
|
"""
|
|
self._run_and_join(script)
|
|
|
|
def assertScriptHasOutput(self, script, expected_output):
|
|
p = subprocess.Popen([sys.executable, "-c", script],
|
|
stdout=subprocess.PIPE)
|
|
rc = p.wait()
|
|
data = p.stdout.read().decode().replace('\r', '')
|
|
self.assertEqual(rc, 0, "Unexpected error")
|
|
self.assertEqual(data, expected_output)
|
|
|
|
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
|
|
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
|
|
def test_4_joining_across_fork_in_worker_thread(self):
|
|
# There used to be a possible deadlock when forking from a child
|
|
# thread. See http://bugs.python.org/issue6643.
|
|
|
|
# The script takes the following steps:
|
|
# - The main thread in the parent process starts a new thread and then
|
|
# tries to join it.
|
|
# - The join operation acquires the Lock inside the thread's _block
|
|
# Condition. (See threading.py:Thread.join().)
|
|
# - We stub out the acquire method on the condition to force it to wait
|
|
# until the child thread forks. (See LOCK ACQUIRED HERE)
|
|
# - The child thread forks. (See LOCK HELD and WORKER THREAD FORKS
|
|
# HERE)
|
|
# - The main thread of the parent process enters Condition.wait(),
|
|
# which releases the lock on the child thread.
|
|
# - The child process returns. Without the necessary fix, when the
|
|
# main thread of the child process (which used to be the child thread
|
|
# in the parent process) attempts to exit, it will try to acquire the
|
|
# lock in the Thread._block Condition object and hang, because the
|
|
# lock was held across the fork.
|
|
|
|
script = """if 1:
|
|
import os, time, threading
|
|
|
|
finish_join = False
|
|
start_fork = False
|
|
|
|
def worker():
|
|
# Wait until this thread's lock is acquired before forking to
|
|
# create the deadlock.
|
|
global finish_join
|
|
while not start_fork:
|
|
time.sleep(0.01)
|
|
# LOCK HELD: Main thread holds lock across this call.
|
|
childpid = os.fork()
|
|
finish_join = True
|
|
if childpid != 0:
|
|
# Parent process just waits for child.
|
|
os.waitpid(childpid, 0)
|
|
# Child process should just return.
|
|
|
|
w = threading.Thread(target=worker)
|
|
|
|
# Stub out the private condition variable's lock acquire method.
|
|
# This acquires the lock and then waits until the child has forked
|
|
# before returning, which will release the lock soon after. If
|
|
# someone else tries to fix this test case by acquiring this lock
|
|
# before forking instead of resetting it, the test case will
|
|
# deadlock when it shouldn't.
|
|
condition = w._block
|
|
orig_acquire = condition.acquire
|
|
call_count_lock = threading.Lock()
|
|
call_count = 0
|
|
def my_acquire():
|
|
global call_count
|
|
global start_fork
|
|
orig_acquire() # LOCK ACQUIRED HERE
|
|
start_fork = True
|
|
if call_count == 0:
|
|
while not finish_join:
|
|
time.sleep(0.01) # WORKER THREAD FORKS HERE
|
|
with call_count_lock:
|
|
call_count += 1
|
|
condition.acquire = my_acquire
|
|
|
|
w.start()
|
|
w.join()
|
|
print('end of main')
|
|
"""
|
|
self.assertScriptHasOutput(script, "end of main\n")
|
|
|
|
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
|
|
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
|
|
def test_5_clear_waiter_locks_to_avoid_crash(self):
|
|
# Check that a spawned thread that forks doesn't segfault on certain
|
|
# platforms, namely OS X. This used to happen if there was a waiter
|
|
# lock in the thread's condition variable's waiters list. Even though
|
|
# we know the lock will be held across the fork, it is not safe to
|
|
# release locks held across forks on all platforms, so releasing the
|
|
# waiter lock caused a segfault on OS X. Furthermore, since locks on
|
|
# OS X are (as of this writing) implemented with a mutex + condition
|
|
# variable instead of a semaphore, while we know that the Python-level
|
|
# lock will be acquired, we can't know if the internal mutex will be
|
|
# acquired at the time of the fork.
|
|
|
|
script = """if True:
|
|
import os, time, threading
|
|
|
|
start_fork = False
|
|
|
|
def worker():
|
|
# Wait until the main thread has attempted to join this thread
|
|
# before continuing.
|
|
while not start_fork:
|
|
time.sleep(0.01)
|
|
childpid = os.fork()
|
|
if childpid != 0:
|
|
# Parent process just waits for child.
|
|
(cpid, rc) = os.waitpid(childpid, 0)
|
|
assert cpid == childpid
|
|
assert rc == 0
|
|
print('end of worker thread')
|
|
else:
|
|
# Child process should just return.
|
|
pass
|
|
|
|
w = threading.Thread(target=worker)
|
|
|
|
# Stub out the private condition variable's _release_save method.
|
|
# This releases the condition's lock and flips the global that
|
|
# causes the worker to fork. At this point, the problematic waiter
|
|
# lock has been acquired once by the waiter and has been put onto
|
|
# the waiters list.
|
|
condition = w._block
|
|
orig_release_save = condition._release_save
|
|
def my_release_save():
|
|
global start_fork
|
|
orig_release_save()
|
|
# Waiter lock held here, condition lock released.
|
|
start_fork = True
|
|
condition._release_save = my_release_save
|
|
|
|
w.start()
|
|
w.join()
|
|
print('end of main thread')
|
|
"""
|
|
output = "end of worker thread\nend of main thread\n"
|
|
self.assertScriptHasOutput(script, output)
|
|
|
|
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
|
|
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
|
|
def test_reinit_tls_after_fork(self):
|
|
# Issue #13817: fork() would deadlock in a multithreaded program with
|
|
# the ad-hoc TLS implementation.
|
|
|
|
def do_fork_and_wait():
|
|
# just fork a child process and wait it
|
|
pid = os.fork()
|
|
if pid > 0:
|
|
os.waitpid(pid, 0)
|
|
else:
|
|
os._exit(0)
|
|
|
|
# start a bunch of threads that will fork() child processes
|
|
threads = []
|
|
for i in range(16):
|
|
t = threading.Thread(target=do_fork_and_wait)
|
|
threads.append(t)
|
|
t.start()
|
|
|
|
for t in threads:
|
|
t.join()
|
|
|
|
@cpython_only
|
|
@unittest.skipIf(_testcapi is None, "need _testcapi module")
|
|
def test_frame_tstate_tracing(self):
|
|
# Issue #14432: Crash when a generator is created in a C thread that is
|
|
# destroyed while the generator is still used. The issue was that a
|
|
# generator contains a frame, and the frame kept a reference to the
|
|
# Python state of the destroyed C thread. The crash occurs when a trace
|
|
# function is setup.
|
|
|
|
def noop_trace(frame, event, arg):
|
|
# no operation
|
|
return noop_trace
|
|
|
|
def generator():
|
|
while 1:
|
|
yield "genereator"
|
|
|
|
def callback():
|
|
if callback.gen is None:
|
|
callback.gen = generator()
|
|
return next(callback.gen)
|
|
callback.gen = None
|
|
|
|
old_trace = sys.gettrace()
|
|
sys.settrace(noop_trace)
|
|
try:
|
|
# Install a trace function
|
|
threading.settrace(noop_trace)
|
|
|
|
# Create a generator in a C thread which exits after the call
|
|
_testcapi.call_in_temporary_c_thread(callback)
|
|
|
|
# Call the generator in a different Python thread, check that the
|
|
# generator didn't keep a reference to the destroyed thread state
|
|
for test in range(3):
|
|
# The trace function is still called here
|
|
callback()
|
|
finally:
|
|
sys.settrace(old_trace)
|
|
|
|
|
|
class ThreadingExceptionTests(BaseTestCase):
|
|
# A RuntimeError should be raised if Thread.start() is called
|
|
# multiple times.
|
|
def test_start_thread_again(self):
|
|
thread = threading.Thread()
|
|
thread.start()
|
|
self.assertRaises(RuntimeError, thread.start)
|
|
|
|
def test_joining_current_thread(self):
|
|
current_thread = threading.current_thread()
|
|
self.assertRaises(RuntimeError, current_thread.join);
|
|
|
|
def test_joining_inactive_thread(self):
|
|
thread = threading.Thread()
|
|
self.assertRaises(RuntimeError, thread.join)
|
|
|
|
def test_daemonize_active_thread(self):
|
|
thread = threading.Thread()
|
|
thread.start()
|
|
self.assertRaises(RuntimeError, setattr, thread, "daemon", True)
|
|
|
|
def test_print_exception(self):
|
|
script = r"""if 1:
|
|
import threading
|
|
import time
|
|
|
|
running = False
|
|
def run():
|
|
global running
|
|
running = True
|
|
while running:
|
|
time.sleep(0.01)
|
|
1.0/0.0
|
|
t = threading.Thread(target=run)
|
|
t.start()
|
|
while not running:
|
|
time.sleep(0.01)
|
|
running = False
|
|
t.join()
|
|
"""
|
|
rc, out, err = assert_python_ok("-c", script)
|
|
self.assertEqual(out, '')
|
|
self.assertIn("Exception in thread", err)
|
|
self.assertIn("Traceback (most recent call last):", err)
|
|
self.assertIn("ZeroDivisionError", err)
|
|
self.assertNotIn("Unhandled exception", err)
|
|
|
|
def test_print_exception_stderr_is_none_1(self):
|
|
script = r"""if 1:
|
|
import sys
|
|
import threading
|
|
import time
|
|
|
|
running = False
|
|
def run():
|
|
global running
|
|
running = True
|
|
while running:
|
|
time.sleep(0.01)
|
|
1.0/0.0
|
|
t = threading.Thread(target=run)
|
|
t.start()
|
|
while not running:
|
|
time.sleep(0.01)
|
|
sys.stderr = None
|
|
running = False
|
|
t.join()
|
|
"""
|
|
rc, out, err = assert_python_ok("-c", script)
|
|
self.assertEqual(out, '')
|
|
self.assertIn("Exception in thread", err)
|
|
self.assertIn("Traceback (most recent call last):", err)
|
|
self.assertIn("ZeroDivisionError", err)
|
|
self.assertNotIn("Unhandled exception", err)
|
|
|
|
def test_print_exception_stderr_is_none_2(self):
|
|
script = r"""if 1:
|
|
import sys
|
|
import threading
|
|
import time
|
|
|
|
running = False
|
|
def run():
|
|
global running
|
|
running = True
|
|
while running:
|
|
time.sleep(0.01)
|
|
1.0/0.0
|
|
sys.stderr = None
|
|
t = threading.Thread(target=run)
|
|
t.start()
|
|
while not running:
|
|
time.sleep(0.01)
|
|
running = False
|
|
t.join()
|
|
"""
|
|
rc, out, err = assert_python_ok("-c", script)
|
|
self.assertEqual(out, '')
|
|
self.assertNotIn("Unhandled exception", err)
|
|
|
|
|
|
class LockTests(lock_tests.LockTests):
|
|
locktype = staticmethod(threading.Lock)
|
|
|
|
class RLockTests(lock_tests.RLockTests):
|
|
locktype = staticmethod(threading.RLock)
|
|
|
|
class EventTests(lock_tests.EventTests):
|
|
eventtype = staticmethod(threading.Event)
|
|
|
|
class ConditionAsRLockTests(lock_tests.RLockTests):
|
|
# An Condition uses an RLock by default and exports its API.
|
|
locktype = staticmethod(threading.Condition)
|
|
|
|
class ConditionTests(lock_tests.ConditionTests):
|
|
condtype = staticmethod(threading.Condition)
|
|
|
|
class SemaphoreTests(lock_tests.SemaphoreTests):
|
|
semtype = staticmethod(threading.Semaphore)
|
|
|
|
class BoundedSemaphoreTests(lock_tests.BoundedSemaphoreTests):
|
|
semtype = staticmethod(threading.BoundedSemaphore)
|
|
|
|
@unittest.skipUnless(sys.platform == 'darwin', 'test macosx problem')
|
|
def test_recursion_limit(self):
|
|
# Issue 9670
|
|
# test that excessive recursion within a non-main thread causes
|
|
# an exception rather than crashing the interpreter on platforms
|
|
# like Mac OS X or FreeBSD which have small default stack sizes
|
|
# for threads
|
|
script = """if True:
|
|
import threading
|
|
|
|
def recurse():
|
|
return recurse()
|
|
|
|
def outer():
|
|
try:
|
|
recurse()
|
|
except RuntimeError:
|
|
pass
|
|
|
|
w = threading.Thread(target=outer)
|
|
w.start()
|
|
w.join()
|
|
print('end of main thread')
|
|
"""
|
|
expected_output = "end of main thread\n"
|
|
p = subprocess.Popen([sys.executable, "-c", script],
|
|
stdout=subprocess.PIPE)
|
|
stdout, stderr = p.communicate()
|
|
data = stdout.decode().replace('\r', '')
|
|
self.assertEqual(p.returncode, 0, "Unexpected error")
|
|
self.assertEqual(data, expected_output)
|
|
|
|
def test_main():
|
|
test.test_support.run_unittest(LockTests, RLockTests, EventTests,
|
|
ConditionAsRLockTests, ConditionTests,
|
|
SemaphoreTests, BoundedSemaphoreTests,
|
|
ThreadTests,
|
|
ThreadJoinOnShutdown,
|
|
ThreadingExceptionTests,
|
|
)
|
|
|
|
if __name__ == "__main__":
|
|
test_main()
|