Commit 7dc72238 authored by Jason Madden's avatar Jason Madden

Fix #750 by making patched threading.RLock interpret timeout the same as the stdlib.

This required a change to our test_threading_2.py: we weren't testing
patched RLocks at all! Now we run the full set on them.

Also add test_threading.py from Python 3.4 and 3.5 to the test suite to
identify any other differences. A few tests have to be commented out
because they rely on reprs or internal class details, but nothing too
severe or concerning.

Locally tox 3.3, 3.4 and 3.5 are all green.
parent d8cb259b
......@@ -7,7 +7,12 @@
1.1rc6 (unreleased)
===================
- TBD
- Python 3: A monkey-patched :class:`threading.RLock` now properly
blocks (or deadlocks) in ``acquire`` if the default value for
*timeout* of -1 is used (which differs from gevent's default of
None). The ``acquire`` method also raises the same :exc:`ValueError`
exceptions that the standard library does for invalid parameters.
Reported in :issue:`750` by Joy Zheng.
1.1rc5 (Feb 24, 2016)
=====================
......
......@@ -282,6 +282,18 @@ reduce the cases of undocumented or non-standard behaviour.
) now throws an exception, just like the documented parameter to the
same stdlib method in Python 3.
- Under Python 3, several standard library methods added ``timeout``
parameters. These often default to -1 to mean "no timeout", whereas
gevent uses a default of ``None`` to mean the same thing,
potentially leading to great confusion and bugs in portable code. In
gevent, using a negative value has always been ill-defined and hard
to reason about. Because of those two things, as of this release,
negative ``timeout`` values should be considered deprecated (unless
otherwise documented). The current ill-defined behaviour is
maintained, but future releases may choose to treat it the same as
``None`` or raise an error. No runtime warnings are issued for this
change for performance reasons.
- The previously undocumented class
``gevent.fileobject.SocketAdapter`` has been removed, as have the
internal ``gevent._util`` module and some internal implementation modules
......
......@@ -160,9 +160,7 @@ class Semaphore(object):
switch = getcurrent().switch
self.rawlink(switch)
try:
# As a tiny efficiency optimization, avoid allocating a timer
# if not needed.
timer = Timeout.start_new(timeout) if timeout is not None else None
timer = Timeout._start_new_or_dummy(timeout)
try:
try:
result = get_hub().switch()
......@@ -172,7 +170,6 @@ class Semaphore(object):
raise
return ex
finally:
if timer is not None:
timer.cancel()
finally:
self.unlink(switch)
......
......@@ -30,7 +30,7 @@ else:
'interrupt_main',
'start_new']
error = __thread__.error
from gevent.hub import getcurrent, GreenletExit
from gevent.hub import getcurrent, GreenletExit, PY3
from gevent.greenlet import Greenlet
from gevent.lock import BoundedSemaphore
from gevent.local import local as _local
......@@ -53,6 +53,26 @@ class LockType(BoundedSemaphore):
# and any other API changes we need to make to match behaviour
_OVER_RELEASE_ERROR = __thread__.error
if PY3:
_TIMEOUT_MAX = __thread__.TIMEOUT_MAX
def acquire(self, blocking=True, timeout=-1):
# Transform the default -1 argument into the None that our
# semaphore implementation expects, and raise the same error
# the stdlib implementation does.
if timeout == -1:
timeout = None
if not blocking and timeout is not None:
raise ValueError("can't specify a timeout for a non-blocking call")
if timeout is not None:
if timeout < 0:
# in C: if(timeout < 0 && timeout != -1)
raise ValueError("timeout value must be strictly positive")
if timeout > self._TIMEOUT_MAX:
raise OverflowError('timeout value is too large')
return BoundedSemaphore.acquire(self, blocking, timeout)
allocate_lock = LockType
......
......@@ -107,11 +107,19 @@ class Timeout(BaseException):
If the *seconds* argument is not given or is ``None`` (e.g.,
``Timeout()``), then the timeout will never expire and never raise
*exception*. This is convenient for creating functions which take
an optional timeout parameter of their own.
an optional timeout parameter of their own. (Note that this is not the same thing
as a *seconds* value of 0.)
.. caution::
A *seconds* value less than 0.0 (e.g., -1) is poorly defined. In the future,
support for negative values is likely to do the same thing as a value
if ``None``.
.. versionchanged:: 1.1b2
If *seconds* is not given or is ``None``, no longer allocate a libev
timer that will never be started.
.. versionchanged:: 1.1
Add warning about negative *seconds* values.
"""
def __init__(self, seconds=None, exception=None, ref=True, priority=-1):
......@@ -167,7 +175,9 @@ class Timeout(BaseException):
# Internal use only in 1.1
# Return an object with a 'cancel' method; if timeout is None,
# this will be a shared instance object that does nothing. Otherwise,
# return an actual Timeout.
# return an actual Timeout. Because negative values are hard to reason about,
# and are often used as sentinels in Python APIs, in the future it's likely
# that a negative timeout will also return the shared instance.
# This saves the previously common idiom of 'timer = Timeout.start_new(t) if t is not None else None'
# followed by 'if timer is not None: timer.cancel()'.
# That idiom was used to avoid any object allocations.
......
"""
Tests for the threading module.
"""
import test.support
from test.support import verbose, strip_python_stderr, import_module, cpython_only
from test.script_helper import assert_python_ok, assert_python_failure
import random
import re
import sys
_thread = import_module('_thread')
threading = import_module('threading')
import time
import unittest
import weakref
import os
import subprocess
from test import lock_tests
# 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',
'hp-ux11')
# 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.support.threading_setup()
def tearDown(self):
test.support.threading_cleanup(*self._threads)
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()
self.assertTrue(not t.is_alive())
self.assertNotEqual(t.ident, 0)
self.assertFalse(t.ident is None)
self.assertTrue(re.match('<TestThread\(.*, stopped -?\d+\)>',
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:
raise unittest.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:
raise unittest.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):
ctypes = import_module("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 = threading.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 = threading.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 threading.ThreadError()
_start_new_thread = threading._start_new_thread
threading._start_new_thread = fail_new_thread
try:
t = threading.Thread(target=lambda: None)
self.assertRaises(threading.ThreadError, 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.
import_module("ctypes")
rc, out, err = assert_python_failure("-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
assert_python_ok("-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)
""")
def test_join_nondaemon_on_shutdown(self):
# Issue 1722344
# Raising SystemExit skipped threading._shutdown
rc, out, err = assert_python_ok("-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
""")
self.assertEqual(out.strip(),
b"Woke up, sleep function is: <built-in function sleep>")
self.assertEqual(err, b"")
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.getswitchinterval()
try:
for i in range(1, 100):
sys.setswitchinterval(i * 0.0002)
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.setswitchinterval(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.assertIsNone(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.assertIsNone(weak_raising_cyclic_object(),
msg=('%d references still around' %
sys.getrefcount(weak_raising_cyclic_object())))
def test_old_threading_api(self):
# Just a quick sanity check to make sure the old method names are
# still present
t = threading.Thread()
t.isDaemon()
t.setDaemon(True)
t.getName()
t.setName("name")
t.isAlive()
e = threading.Event()
e.isSet()
threading.activeCount()
def test_repr_daemon(self):
t = threading.Thread()
self.assertFalse('daemon' in repr(t))
t.daemon = True
self.assertTrue('daemon' in repr(t))
def test_deamon_param(self):
t = threading.Thread()
self.assertFalse(t.daemon)
t = threading.Thread(daemon=False)
self.assertFalse(t.daemon)
t = threading.Thread(daemon=True)
self.assertTrue(t.daemon)
@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, b'')
self.assertEqual(err, b'')
@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.getswitchinterval()
self.addCleanup(sys.setswitchinterval, old_interval)
# Make the bug more likely to manifest.
sys.setswitchinterval(1e-6)
for i in range(20):
t = threading.Thread(target=lambda: None)
t.start()
self.addCleanup(t.join)
pid = os.fork()
if pid == 0:
os._exit(1 if t.is_alive() else 0)
else:
pid, status = os.waitpid(pid, 0)
self.assertEqual(0, status)
def test_main_thread(self):
main = threading.main_thread()
self.assertEqual(main.name, 'MainThread')
self.assertEqual(main.ident, threading.current_thread().ident)
self.assertEqual(main.ident, threading.get_ident())
def f():
self.assertNotEqual(threading.main_thread().ident,
threading.current_thread().ident)
th = threading.Thread(target=f)
th.start()
th.join()
@unittest.skipUnless(hasattr(os, 'fork'), "test needs os.fork()")
@unittest.skipUnless(hasattr(os, 'waitpid'), "test needs os.waitpid()")
def test_main_thread_after_fork(self):
code = """if 1:
import os, threading
pid = os.fork()
if pid == 0:
main = threading.main_thread()
print(main.name)
print(main.ident == threading.current_thread().ident)
print(main.ident == threading.get_ident())
else:
os.waitpid(pid, 0)
"""
_, out, err = assert_python_ok("-c", code)
data = out.decode().replace('\r', '')
self.assertEqual(err, b"")
self.assertEqual(data, "MainThread\nTrue\nTrue\n")
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
@unittest.skipUnless(hasattr(os, 'fork'), "test needs os.fork()")
@unittest.skipUnless(hasattr(os, 'waitpid'), "test needs os.waitpid()")
def test_main_thread_after_fork_from_nonmain_thread(self):
code = """if 1:
import os, threading, sys
def f():
pid = os.fork()
if pid == 0:
main = threading.main_thread()
print(main.name)
print(main.ident == threading.current_thread().ident)
print(main.ident == threading.get_ident())
# stdout is fully buffered because not a tty,
# we have to flush before exit.
sys.stdout.flush()
else:
os.waitpid(pid, 0)
th = threading.Thread(target=f)
th.start()
th.join()
"""
_, out, err = assert_python_ok("-c", code)
data = out.decode().replace('\r', '')
self.assertEqual(err, b"")
self.assertEqual(data, "Thread-1\nTrue\nTrue\n")
def test_tstate_lock(self):
# Test an implementation detail of Thread objects.
started = _thread.allocate_lock()
finish = _thread.allocate_lock()
started.acquire()
finish.acquire()
def f():
started.release()
finish.acquire()
time.sleep(0.01)
# The tstate lock is None until the thread is started
t = threading.Thread(target=f)
self.assertIs(t._tstate_lock, None)
t.start()
started.acquire()
self.assertTrue(t.is_alive())
# The tstate lock can't be acquired when the thread is running
# (or suspended).
tstate_lock = t._tstate_lock
self.assertFalse(tstate_lock.acquire(timeout=0), False)
finish.release()
# When the thread ends, the state_lock can be successfully
# acquired.
self.assertTrue(tstate_lock.acquire(timeout=5), False)
# But is_alive() is still True: we hold _tstate_lock now, which
# prevents is_alive() from knowing the thread's end-of-life C code
# is done.
self.assertTrue(t.is_alive())
# Let is_alive() find out the C code is done.
tstate_lock.release()
self.assertFalse(t.is_alive())
# And verify the thread disposed of _tstate_lock.
self.assertTrue(t._tstate_lock is None)
def test_repr_stopped(self):
# Verify that "stopped" shows up in repr(Thread) appropriately.
started = _thread.allocate_lock()
finish = _thread.allocate_lock()
started.acquire()
finish.acquire()
def f():
started.release()
finish.acquire()
t = threading.Thread(target=f)
t.start()
started.acquire()
self.assertIn("started", repr(t))
finish.release()
# "stopped" should appear in the repr in a reasonable amount of time.
# Implementation detail: as of this writing, that's trivially true
# if .join() is called, and almost trivially true if .is_alive() is
# called. The detail we're testing here is that "stopped" shows up
# "all on its own".
LOOKING_FOR = "stopped"
for i in range(500):
if LOOKING_FOR in repr(t):
break
time.sleep(0.01)
self.assertIn(LOOKING_FOR, repr(t)) # we waited at least 5 seconds
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)
@cpython_only
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 "generator"
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
import _testcapi
_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 ThreadJoinOnShutdown(BaseTestCase):
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')
# stdout is fully buffered because not a tty, we have to flush
# before exit.
sys.stdout.flush()
\n""" + script
rc, out, err = assert_python_ok("-c", script)
data = out.decode().replace('\r', '')
self.assertEqual(data, "end of main\nend of thread\n")
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)
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
def test_4_daemon_threads(self):
# Check that a daemon thread cannot crash the interpreter on shutdown
# by manipulating internal structures that are being disposed of in
# the main thread.
script = """if True:
import os
import random
import sys
import time
import threading
thread_has_run = set()
def random_io():
'''Loop for a while sleeping random tiny amounts and doing some I/O.'''
while True:
in_f = open(os.__file__, 'rb')
stuff = in_f.read(200)
null_f = open(os.devnull, 'wb')
null_f.write(stuff)
time.sleep(random.random() / 1995)
null_f.close()
in_f.close()
thread_has_run.add(threading.current_thread())
def main():
count = 0
for _ in range(40):
new_thread = threading.Thread(target=random_io)
new_thread.daemon = True
new_thread.start()
count += 1
while len(thread_has_run) < count:
time.sleep(0.001)
# Trigger process shutdown
sys.exit(0)
main()
"""
rc, out, err = assert_python_ok('-c', script)
self.assertFalse(err)
@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()
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
def test_clear_threads_states_after_fork(self):
# Issue #17094: check that threads states are cleared after fork()
# start a bunch of threads
threads = []
for i in range(16):
t = threading.Thread(target=lambda : time.sleep(0.3))
threads.append(t)
t.start()
pid = os.fork()
if pid == 0:
# check that threads states have been cleared
if len(sys._current_frames()) == 1:
os._exit(0)
else:
os._exit(1)
else:
_, status = os.waitpid(pid, 0)
self.assertEqual(0, status)
for t in threads:
t.join()
class SubinterpThreadingTests(BaseTestCase):
def test_threads_join(self):
# Non-daemon threads should be joined at subinterpreter shutdown
# (issue #18808)
r, w = os.pipe()
self.addCleanup(os.close, r)
self.addCleanup(os.close, w)
code = r"""if 1:
import os
import threading
import time
def f():
# Sleep a bit so that the thread is still running when
# Py_EndInterpreter is called.
time.sleep(0.05)
os.write(%d, b"x")
threading.Thread(target=f).start()
""" % (w,)
ret = test.support.run_in_subinterp(code)
self.assertEqual(ret, 0)
# The thread was joined properly.
self.assertEqual(os.read(r, 1), b"x")
def test_threads_join_2(self):
# Same as above, but a delay gets introduced after the thread's
# Python code returned but before the thread state is deleted.
# To achieve this, we register a thread-local object which sleeps
# a bit when deallocated.
r, w = os.pipe()
self.addCleanup(os.close, r)
self.addCleanup(os.close, w)
code = r"""if 1:
import os
import threading
import time
class Sleeper:
def __del__(self):
time.sleep(0.05)
tls = threading.local()
def f():
# Sleep a bit so that the thread is still running when
# Py_EndInterpreter is called.
time.sleep(0.05)
tls.x = Sleeper()
os.write(%d, b"x")
threading.Thread(target=f).start()
""" % (w,)
ret = test.support.run_in_subinterp(code)
self.assertEqual(ret, 0)
# The thread was joined properly.
self.assertEqual(os.read(r, 1), b"x")
@cpython_only
def test_daemon_threads_fatal_error(self):
subinterp_code = r"""if 1:
import os
import threading
import time
def f():
# Make sure the daemon thread is still running when
# Py_EndInterpreter is called.
time.sleep(10)
threading.Thread(target=f, daemon=True).start()
"""
script = r"""if 1:
import _testcapi
_testcapi.run_in_subinterp(%r)
""" % (subinterp_code,)
with test.support.SuppressCrashReport():
rc, out, err = assert_python_failure("-c", script)
self.assertIn("Fatal Python error: Py_EndInterpreter: "
"not the last thread", err.decode())
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_releasing_unacquired_lock(self):
lock = threading.Lock()
self.assertRaises(RuntimeError, lock.release)
@unittest.skipUnless(sys.platform == 'darwin' and test.support.python_is_optimized(),
'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, stderr=subprocess.PIPE)
stdout, stderr = p.communicate()
data = stdout.decode().replace('\r', '')
self.assertEqual(p.returncode, 0, "Unexpected error: " + stderr.decode())
self.assertEqual(data, expected_output)
def test_print_exception(self):
script = r"""if True:
import threading
import time
running = False
def run():
global running
running = True
while running:
time.sleep(0.01)
1/0
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, b'')
err = err.decode()
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 True:
import sys
import threading
import time
running = False
def run():
global running
running = True
while running:
time.sleep(0.01)
1/0
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, b'')
err = err.decode()
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 True:
import sys
import threading
import time
running = False
def run():
global running
running = True
while running:
time.sleep(0.01)
1/0
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, b'')
self.assertNotIn("Unhandled exception", err.decode())
class TimerTests(BaseTestCase):
def setUp(self):
BaseTestCase.setUp(self)
self.callback_args = []
self.callback_event = threading.Event()
def test_init_immutable_default_args(self):
# Issue 17435: constructor defaults were mutable objects, they could be
# mutated via the object attributes and affect other Timer objects.
timer1 = threading.Timer(0.01, self._callback_spy)
timer1.start()
self.callback_event.wait()
timer1.args.append("blah")
timer1.kwargs["foo"] = "bar"
self.callback_event.clear()
timer2 = threading.Timer(0.01, self._callback_spy)
timer2.start()
self.callback_event.wait()
self.assertEqual(len(self.callback_args), 2)
self.assertEqual(self.callback_args, [((), {}), ((), {})])
def _callback_spy(self, *args, **kwargs):
self.callback_args.append((args[:], kwargs.copy()))
self.callback_event.set()
class LockTests(lock_tests.LockTests):
locktype = staticmethod(threading.Lock)
class PyRLockTests(lock_tests.RLockTests):
locktype = staticmethod(threading._PyRLock)
@unittest.skipIf(threading._CRLock is None, 'RLock not implemented in C')
class CRLockTests(lock_tests.RLockTests):
locktype = staticmethod(threading._CRLock)
class EventTests(lock_tests.EventTests):
eventtype = staticmethod(threading.Event)
@unittest.skip("gevent may/not suffer from Python bug 13502")
def test_set_and_clear(self):
pass
@unittest.skip("not on gevent")
def test_reset_internal_locks(self):
pass
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)
class BarrierTests(lock_tests.BarrierTests):
barriertype = staticmethod(threading.Barrier)
if __name__ == "__main__":
unittest.main()
"""
Tests for the threading module.
"""
import test.support
from test.support import verbose, strip_python_stderr, import_module, cpython_only
from test.support.script_helper import assert_python_ok, assert_python_failure
import random
import re
import sys
_thread = import_module('_thread')
threading = import_module('threading')
import time
import unittest
import weakref
import os
import subprocess
from test import lock_tests
# 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',
'hp-ux11')
# 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.support.threading_setup()
def tearDown(self):
test.support.threading_cleanup(*self._threads)
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()
self.assertTrue(not t.is_alive())
self.assertNotEqual(t.ident, 0)
self.assertFalse(t.ident is None)
self.assertTrue(re.match('<TestThread\(.*, stopped -?\d+\)>',
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:
raise unittest.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:
raise unittest.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):
ctypes = import_module("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 = threading.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 = threading.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 threading.ThreadError()
_start_new_thread = threading._start_new_thread
threading._start_new_thread = fail_new_thread
try:
t = threading.Thread(target=lambda: None)
self.assertRaises(threading.ThreadError, 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.
import_module("ctypes")
rc, out, err = assert_python_failure("-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
assert_python_ok("-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)
""")
def test_join_nondaemon_on_shutdown(self):
# Issue 1722344
# Raising SystemExit skipped threading._shutdown
rc, out, err = assert_python_ok("-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
""")
self.assertEqual(out.strip(),
b"Woke up, sleep function is: <built-in function sleep>")
self.assertEqual(err, b"")
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.getswitchinterval()
try:
for i in range(1, 100):
sys.setswitchinterval(i * 0.0002)
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.setswitchinterval(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.assertIsNone(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.assertIsNone(weak_raising_cyclic_object(),
msg=('%d references still around' %
sys.getrefcount(weak_raising_cyclic_object())))
def test_old_threading_api(self):
# Just a quick sanity check to make sure the old method names are
# still present
t = threading.Thread()
t.isDaemon()
t.setDaemon(True)
t.getName()
t.setName("name")
t.isAlive()
e = threading.Event()
e.isSet()
threading.activeCount()
def test_repr_daemon(self):
t = threading.Thread()
self.assertFalse('daemon' in repr(t))
t.daemon = True
self.assertTrue('daemon' in repr(t))
def test_deamon_param(self):
t = threading.Thread()
self.assertFalse(t.daemon)
t = threading.Thread(daemon=False)
self.assertFalse(t.daemon)
t = threading.Thread(daemon=True)
self.assertTrue(t.daemon)
@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, b'')
self.assertEqual(err, b'')
@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.getswitchinterval()
self.addCleanup(sys.setswitchinterval, old_interval)
# Make the bug more likely to manifest.
sys.setswitchinterval(1e-6)
for i in range(20):
t = threading.Thread(target=lambda: None)
t.start()
self.addCleanup(t.join)
pid = os.fork()
if pid == 0:
os._exit(1 if t.is_alive() else 0)
else:
pid, status = os.waitpid(pid, 0)
self.assertEqual(0, status)
def test_main_thread(self):
main = threading.main_thread()
self.assertEqual(main.name, 'MainThread')
self.assertEqual(main.ident, threading.current_thread().ident)
self.assertEqual(main.ident, threading.get_ident())
def f():
self.assertNotEqual(threading.main_thread().ident,
threading.current_thread().ident)
th = threading.Thread(target=f)
th.start()
th.join()
@unittest.skipUnless(hasattr(os, 'fork'), "test needs os.fork()")
@unittest.skipUnless(hasattr(os, 'waitpid'), "test needs os.waitpid()")
def test_main_thread_after_fork(self):
code = """if 1:
import os, threading
pid = os.fork()
if pid == 0:
main = threading.main_thread()
print(main.name)
print(main.ident == threading.current_thread().ident)
print(main.ident == threading.get_ident())
else:
os.waitpid(pid, 0)
"""
_, out, err = assert_python_ok("-c", code)
data = out.decode().replace('\r', '')
self.assertEqual(err, b"")
self.assertEqual(data, "MainThread\nTrue\nTrue\n")
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
@unittest.skipUnless(hasattr(os, 'fork'), "test needs os.fork()")
@unittest.skipUnless(hasattr(os, 'waitpid'), "test needs os.waitpid()")
def test_main_thread_after_fork_from_nonmain_thread(self):
code = """if 1:
import os, threading, sys
def f():
pid = os.fork()
if pid == 0:
main = threading.main_thread()
print(main.name)
print(main.ident == threading.current_thread().ident)
print(main.ident == threading.get_ident())
# stdout is fully buffered because not a tty,
# we have to flush before exit.
sys.stdout.flush()
else:
os.waitpid(pid, 0)
th = threading.Thread(target=f)
th.start()
th.join()
"""
_, out, err = assert_python_ok("-c", code)
data = out.decode().replace('\r', '')
self.assertEqual(err, b"")
self.assertEqual(data, "Thread-1\nTrue\nTrue\n")
def test_tstate_lock(self):
# Test an implementation detail of Thread objects.
started = _thread.allocate_lock()
finish = _thread.allocate_lock()
started.acquire()
finish.acquire()
def f():
started.release()
finish.acquire()
time.sleep(0.01)
# The tstate lock is None until the thread is started
t = threading.Thread(target=f)
self.assertIs(t._tstate_lock, None)
t.start()
started.acquire()
self.assertTrue(t.is_alive())
# The tstate lock can't be acquired when the thread is running
# (or suspended).
tstate_lock = t._tstate_lock
self.assertFalse(tstate_lock.acquire(timeout=0), False)
finish.release()
# When the thread ends, the state_lock can be successfully
# acquired.
self.assertTrue(tstate_lock.acquire(timeout=5), False)
# But is_alive() is still True: we hold _tstate_lock now, which
# prevents is_alive() from knowing the thread's end-of-life C code
# is done.
self.assertTrue(t.is_alive())
# Let is_alive() find out the C code is done.
tstate_lock.release()
self.assertFalse(t.is_alive())
# And verify the thread disposed of _tstate_lock.
self.assertTrue(t._tstate_lock is None)
def test_repr_stopped(self):
# Verify that "stopped" shows up in repr(Thread) appropriately.
started = _thread.allocate_lock()
finish = _thread.allocate_lock()
started.acquire()
finish.acquire()
def f():
started.release()
finish.acquire()
t = threading.Thread(target=f)
t.start()
started.acquire()
self.assertIn("started", repr(t))
finish.release()
# "stopped" should appear in the repr in a reasonable amount of time.
# Implementation detail: as of this writing, that's trivially true
# if .join() is called, and almost trivially true if .is_alive() is
# called. The detail we're testing here is that "stopped" shows up
# "all on its own".
LOOKING_FOR = "stopped"
for i in range(500):
if LOOKING_FOR in repr(t):
break
time.sleep(0.01)
self.assertIn(LOOKING_FOR, repr(t)) # we waited at least 5 seconds
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)
@cpython_only
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 "generator"
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
import _testcapi
_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 ThreadJoinOnShutdown(BaseTestCase):
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')
# stdout is fully buffered because not a tty, we have to flush
# before exit.
sys.stdout.flush()
\n""" + script
rc, out, err = assert_python_ok("-c", script)
data = out.decode().replace('\r', '')
self.assertEqual(data, "end of main\nend of thread\n")
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)
@unittest.skipIf(sys.platform in platforms_to_skip, "due to known OS bug")
def test_4_daemon_threads(self):
# Check that a daemon thread cannot crash the interpreter on shutdown
# by manipulating internal structures that are being disposed of in
# the main thread.
script = """if True:
import os
import random
import sys
import time
import threading
thread_has_run = set()
def random_io():
'''Loop for a while sleeping random tiny amounts and doing some I/O.'''
while True:
in_f = open(os.__file__, 'rb')
stuff = in_f.read(200)
null_f = open(os.devnull, 'wb')
null_f.write(stuff)
time.sleep(random.random() / 1995)
null_f.close()
in_f.close()
thread_has_run.add(threading.current_thread())
def main():
count = 0
for _ in range(40):
new_thread = threading.Thread(target=random_io)
new_thread.daemon = True
new_thread.start()
count += 1
while len(thread_has_run) < count:
time.sleep(0.001)
# Trigger process shutdown
sys.exit(0)
main()
"""
rc, out, err = assert_python_ok('-c', script)
self.assertFalse(err)
@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()
@unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
def test_clear_threads_states_after_fork(self):
# Issue #17094: check that threads states are cleared after fork()
# start a bunch of threads
threads = []
for i in range(16):
t = threading.Thread(target=lambda : time.sleep(0.3))
threads.append(t)
t.start()
pid = os.fork()
if pid == 0:
# check that threads states have been cleared
if len(sys._current_frames()) == 1:
os._exit(0)
else:
os._exit(1)
else:
_, status = os.waitpid(pid, 0)
self.assertEqual(0, status)
for t in threads:
t.join()
class SubinterpThreadingTests(BaseTestCase):
def test_threads_join(self):
# Non-daemon threads should be joined at subinterpreter shutdown
# (issue #18808)
r, w = os.pipe()
self.addCleanup(os.close, r)
self.addCleanup(os.close, w)
code = r"""if 1:
import os
import threading
import time
def f():
# Sleep a bit so that the thread is still running when
# Py_EndInterpreter is called.
time.sleep(0.05)
os.write(%d, b"x")
threading.Thread(target=f).start()
""" % (w,)
ret = test.support.run_in_subinterp(code)
self.assertEqual(ret, 0)
# The thread was joined properly.
self.assertEqual(os.read(r, 1), b"x")
def test_threads_join_2(self):
# Same as above, but a delay gets introduced after the thread's
# Python code returned but before the thread state is deleted.
# To achieve this, we register a thread-local object which sleeps
# a bit when deallocated.
r, w = os.pipe()
self.addCleanup(os.close, r)
self.addCleanup(os.close, w)
code = r"""if 1:
import os
import threading
import time
class Sleeper:
def __del__(self):
time.sleep(0.05)
tls = threading.local()
def f():
# Sleep a bit so that the thread is still running when
# Py_EndInterpreter is called.
time.sleep(0.05)
tls.x = Sleeper()
os.write(%d, b"x")
threading.Thread(target=f).start()
""" % (w,)
ret = test.support.run_in_subinterp(code)
self.assertEqual(ret, 0)
# The thread was joined properly.
self.assertEqual(os.read(r, 1), b"x")
@cpython_only
def test_daemon_threads_fatal_error(self):
subinterp_code = r"""if 1:
import os
import threading
import time
def f():
# Make sure the daemon thread is still running when
# Py_EndInterpreter is called.
time.sleep(10)
threading.Thread(target=f, daemon=True).start()
"""
script = r"""if 1:
import _testcapi
_testcapi.run_in_subinterp(%r)
""" % (subinterp_code,)
with test.support.SuppressCrashReport():
rc, out, err = assert_python_failure("-c", script)
self.assertIn("Fatal Python error: Py_EndInterpreter: "
"not the last thread", err.decode())
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_releasing_unacquired_lock(self):
lock = threading.Lock()
self.assertRaises(RuntimeError, lock.release)
@unittest.skipUnless(sys.platform == 'darwin' and test.support.python_is_optimized(),
'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 RecursionError:
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, stderr=subprocess.PIPE)
stdout, stderr = p.communicate()
data = stdout.decode().replace('\r', '')
self.assertEqual(p.returncode, 0, "Unexpected error: " + stderr.decode())
self.assertEqual(data, expected_output)
def test_print_exception(self):
script = r"""if True:
import threading
import time
running = False
def run():
global running
running = True
while running:
time.sleep(0.01)
1/0
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, b'')
err = err.decode()
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 True:
import sys
import threading
import time
running = False
def run():
global running
running = True
while running:
time.sleep(0.01)
1/0
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, b'')
err = err.decode()
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 True:
import sys
import threading
import time
running = False
def run():
global running
running = True
while running:
time.sleep(0.01)
1/0
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, b'')
self.assertNotIn("Unhandled exception", err.decode())
class TimerTests(BaseTestCase):
def setUp(self):
BaseTestCase.setUp(self)
self.callback_args = []
self.callback_event = threading.Event()
def test_init_immutable_default_args(self):
# Issue 17435: constructor defaults were mutable objects, they could be
# mutated via the object attributes and affect other Timer objects.
timer1 = threading.Timer(0.01, self._callback_spy)
timer1.start()
self.callback_event.wait()
timer1.args.append("blah")
timer1.kwargs["foo"] = "bar"
self.callback_event.clear()
timer2 = threading.Timer(0.01, self._callback_spy)
timer2.start()
self.callback_event.wait()
self.assertEqual(len(self.callback_args), 2)
self.assertEqual(self.callback_args, [((), {}), ((), {})])
def _callback_spy(self, *args, **kwargs):
self.callback_args.append((args[:], kwargs.copy()))
self.callback_event.set()
class LockTests(lock_tests.LockTests):
locktype = staticmethod(threading.Lock)
@unittest.skip("not on gevent")
def test_locked_repr(self):
pass
@unittest.skip("not on gevent")
def test_repr(self):
pass
class PyRLockTests(lock_tests.RLockTests):
locktype = staticmethod(threading._PyRLock)
@unittest.skipIf(threading._CRLock is None, 'RLock not implemented in C')
class CRLockTests(lock_tests.RLockTests):
locktype = staticmethod(threading._CRLock)
class EventTests(lock_tests.EventTests):
eventtype = staticmethod(threading.Event)
@unittest.skip("gevent may/not suffer from Python bug 13502")
def test_set_and_clear(self):
pass
@unittest.skip("not on gevent")
def test_reset_internal_locks(self):
pass
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)
class BarrierTests(lock_tests.BarrierTests):
barriertype = staticmethod(threading.Barrier)
if __name__ == "__main__":
unittest.main()
......@@ -44,7 +44,7 @@ class Bunch(object):
self.finished.append(tid)
while not self._can_exit:
_wait()
for i in range(n):
for _ in range(n):
start_new_thread(task, ())
def wait_for_started(self):
......@@ -73,6 +73,9 @@ class BaseLockTests(BaseTestCase):
Tests for both recursive and non-recursive locks.
"""
def locktype(self):
raise NotImplementedError()
def test_constructor(self):
lock = self.locktype()
del lock
......@@ -244,6 +247,9 @@ class EventTests(BaseTestCase):
Tests for Event objects.
"""
def eventtype(self):
raise NotImplementedError()
def test_is_set(self):
evt = self.eventtype()
self.assertFalse(evt.is_set())
......@@ -316,6 +322,9 @@ class ConditionTests(BaseTestCase):
Tests for condition variables.
"""
def condtype(self, *args):
raise NotImplementedError()
def test_acquire(self):
cond = self.condtype()
# Be default we have an RLock: the condition can be acquired multiple
......@@ -421,6 +430,9 @@ class BaseSemaphoreTests(BaseTestCase):
Common tests for {bounded, unbounded} semaphore objects.
"""
def semtype(self, *args):
raise NotImplementedError()
def test_constructor(self):
self.assertRaises(ValueError, self.semtype, value = -1)
# Py3 doesn't have sys.maxint
......@@ -459,13 +471,13 @@ class BaseSemaphoreTests(BaseTestCase):
_wait()
self.assertEqual(results1 + results2, [0] * 6)
phase_num = 1
for i in range(7):
for _ in range(7):
sem.release()
while len(results1) + len(results2) < 13:
_wait()
self.assertEqual(sorted(results1 + results2), [0] * 6 + [1] * 7)
phase_num = 2
for i in range(6):
for _ in range(6):
sem.release()
while len(results1) + len(results2) < 19:
_wait()
......@@ -554,3 +566,6 @@ class BoundedSemaphoreTests(BaseSemaphoreTests):
sem.acquire()
sem.release()
self.assertRaises(ValueError, sem.release)
if __name__ == '__main__':
print("This module contains no tests; it is used by other test cases like test_threading_2")
......@@ -222,6 +222,33 @@ if hasattr(sys, 'pypy_version_info'):
# https://bitbucket.org/cffi/cffi/issue/152/handling-errors-from-signal-handlers-in
]
# Generic Python 3
if sys.version_info[0] == 3:
disabled_tests += [
# Triggers the crash reporter
'test_threading.SubinterpThreadingTests.test_daemon_threads_fatal_error',
# Relies on an implementation detail, Thread._tstate_lock
'test_threading.ThreadTests.test_tstate_lock',
# Relies on an implementation detail (reprs); we have our own version
'test_threading.ThreadTests.test_various_ops',
'test_threading.ThreadTests.test_various_ops_large_stack',
'test_threading.ThreadTests.test_various_ops_small_stack',
# Relies on Event having a _cond and an _reset_internal_locks()
# XXX: These are commented out in the source code of test_threading because
# this doesn't work.
# 'lock_tests.EventTests.test_reset_internal_locks',
# Python bug 13502. We may or may not suffer from this as its
# basically a timing race condition.
# XXX Same as above
# 'lock_tests.EventTests.test_set_and_clear',
]
if sys.version_info[:2] == (3, 4) and sys.version_info[:3] < (3, 4, 4):
# Older versions have some issues with the SSL tests. Seen on Appveyor
disabled_tests += [
......@@ -310,6 +337,14 @@ if sys.version_info[:2] >= (3, 5):
'test_socket.GeneralModuleTests.test_repr',
'test_socket.GeneralModuleTests.test_str_for_enums',
'test_socket.GeneralModuleTests.testGetaddrinfo',
# Relies on the regex of the repr having the locked state (TODO: it'd be nice if
# we did that).
# XXX: These are commented out in the source code of test_threading because
# this doesn't work.
# 'lock_tests.LockTests.lest_locked_repr',
# 'lock_tests.LockTests.lest_repr',
]
if os.environ.get('GEVENT_RESOLVER') == 'ares':
......
......@@ -84,6 +84,7 @@ class TestTrace(unittest.TestCase):
else:
old = None
PYPY = hasattr(sys, 'pypy_version_info')
PY3 = sys.version_info[0] > 2
lst = []
# we should be able to use unrelated locks from within the trace function
l = allocate_lock()
......@@ -104,7 +105,8 @@ class TestTrace(unittest.TestCase):
finally:
sys.settrace(old)
if not PYPY:
if not PYPY and not PY3:
# Py3 overrides acquire in Python to do argument checking
self.assertEqual(lst, [], "trace not empty")
else:
# Have an assert so that we know if we miscompile
......@@ -117,6 +119,7 @@ class TestTrace(unittest.TestCase):
else:
old = None
PYPY = hasattr(sys, 'pypy_version_info')
PY3 = sys.version_info[0] > 2
lst = []
e = None
# we should not be able to use the same lock from within the trace function
......@@ -137,7 +140,8 @@ class TestTrace(unittest.TestCase):
finally:
sys.settrace(old)
if not PYPY:
if not PYPY and not PY3:
# Py3 overrides acquire in Python to do argument checking
self.assertEqual(lst, [], "trace not empty")
else:
# Have an assert so that we know if we miscompile
......
......@@ -9,6 +9,11 @@ from gevent.thread import allocate_lock as Lock
import threading
threading.Event = Event
threading.Lock = Lock
# XXX: We're completely patching around the allocate_lock
# patch we try to do with RLock; our monkey patch doesn't
# behave this way, why do we do it in tests? Save it so we can
# at least access it sometimes.
threading.NativeRLock = threading.RLock
threading.RLock = RLock
threading.Semaphore = Semaphore
threading.BoundedSemaphore = BoundedSemaphore
......@@ -522,6 +527,10 @@ class LockTests(lock_tests.LockTests):
class RLockTests(lock_tests.RLockTests):
locktype = staticmethod(threading.RLock)
class NativeRLockTests(lock_tests.RLockTests):
# XXX: See comments at the top of the file for the difference
# between this and RLockTests, and why its weird.
locktype = staticmethod(threading.NativeRLock)
class EventTests(lock_tests.EventTests):
eventtype = staticmethod(threading.Event)
......@@ -551,6 +560,7 @@ def main():
ThreadTests,
ThreadJoinOnShutdown,
ThreadingExceptionTests,
NativeRLockTests,
)
if __name__ == "__main__":
......
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