lib-python.2.7.test.test_threadsignals.py Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of jython-standalone Show documentation

Jython is an implementation of the high-level, dynamic, object-oriented language Python written in 100% Pure Java, and seamlessly integrated with the Java platform. It thus allows you to run Python on any Java platform.

The newest version!

"""PyUnit testing that threads honor our signal semantics"""

import unittest
import signal
import os
import sys
from test.test_support import run_unittest, import_module, reap_threads
thread = import_module('thread')

if sys.platform[:3] in ('win', 'os2') or sys.platform=='riscos':
    raise unittest.SkipTest, "Can't test signal on %s" % sys.platform

process_pid = os.getpid()
signalled_all=thread.allocate_lock()


def registerSignals(for_usr1, for_usr2, for_alrm):
    usr1 = signal.signal(signal.SIGUSR1, for_usr1)
    usr2 = signal.signal(signal.SIGUSR2, for_usr2)
    alrm = signal.signal(signal.SIGALRM, for_alrm)
    return usr1, usr2, alrm


# The signal handler. Just note that the signal occurred and
# from who.
def handle_signals(sig,frame):
    signal_blackboard[sig]['tripped'] += 1
    signal_blackboard[sig]['tripped_by'] = thread.get_ident()

# a function that will be spawned as a separate thread.
def send_signals():
    os.kill(process_pid, signal.SIGUSR1)
    os.kill(process_pid, signal.SIGUSR2)
    signalled_all.release()

class ThreadSignals(unittest.TestCase):
    """Test signal handling semantics of threads.
       We spawn a thread, have the thread send two signals, and
       wait for it to finish. Check that we got both signals
       and that they were run by the main thread.
    """
    @reap_threads
    def test_signals(self):
        signalled_all.acquire()
        self.spawnSignallingThread()
        signalled_all.acquire()
        # the signals that we asked the kernel to send
        # will come back, but we don't know when.
        # (it might even be after the thread exits
        # and might be out of order.)  If we haven't seen
        # the signals yet, send yet another signal and
        # wait for it return.
        if signal_blackboard[signal.SIGUSR1]['tripped'] == 0 \
           or signal_blackboard[signal.SIGUSR2]['tripped'] == 0:
            signal.alarm(1)
            signal.pause()
            signal.alarm(0)

        self.assertEqual( signal_blackboard[signal.SIGUSR1]['tripped'], 1)
        self.assertEqual( signal_blackboard[signal.SIGUSR1]['tripped_by'],
                           thread.get_ident())
        self.assertEqual( signal_blackboard[signal.SIGUSR2]['tripped'], 1)
        self.assertEqual( signal_blackboard[signal.SIGUSR2]['tripped_by'],
                           thread.get_ident())
        signalled_all.release()

    def spawnSignallingThread(self):
        thread.start_new_thread(send_signals, ())


def test_main():
    global signal_blackboard

    signal_blackboard = { signal.SIGUSR1 : {'tripped': 0, 'tripped_by': 0 },
                          signal.SIGUSR2 : {'tripped': 0, 'tripped_by': 0 },
                          signal.SIGALRM : {'tripped': 0, 'tripped_by': 0 } }

    oldsigs = registerSignals(handle_signals, handle_signals, handle_signals)
    try:
        run_unittest(ThreadSignals)
    finally:
        registerSignals(*oldsigs)

if __name__ == '__main__':
    test_main()