Patch #1583 by Adam Olsen.
This adds signal.set_wakeup_fd(fd) which sets a file descriptor to
which a zero byte will be written whenever a C exception handler runs.
I added a simple C API as well, PySignal_SetWakeupFd(fd).
diff --git a/Lib/test/test_signal.py b/Lib/test/test_signal.py
index 892f519..8cf82f4 100644
--- a/Lib/test/test_signal.py
+++ b/Lib/test/test_signal.py
@@ -165,12 +165,59 @@
self.assertRaises(TypeError, signal.signal,
signal.SIGUSR1, None)
+class WakeupSignalTests(unittest.TestCase):
+ TIMEOUT_FULL = 10
+ TIMEOUT_HALF = 5
+
+ def test_wakeup_fd_early(self):
+ import select
+
+ signal.alarm(1)
+ before_time = time.time()
+ # We attempt to get a signal during the sleep,
+ # before select is called
+ time.sleep(self.TIMEOUT_FULL)
+ mid_time = time.time()
+ self.assert_(mid_time - before_time < self.TIMEOUT_HALF)
+ select.select([self.read], [], [], self.TIMEOUT_FULL)
+ after_time = time.time()
+ self.assert_(after_time - mid_time < self.TIMEOUT_HALF)
+
+ def test_wakeup_fd_during(self):
+ import select
+
+ signal.alarm(1)
+ before_time = time.time()
+ # We attempt to get a signal during the select call
+ self.assertRaises(select.error, select.select,
+ [self.read], [], [], self.TIMEOUT_FULL)
+ after_time = time.time()
+ self.assert_(after_time - before_time < self.TIMEOUT_HALF)
+
+ def setUp(self):
+ import fcntl
+
+ self.alrm = signal.signal(signal.SIGALRM, lambda x,y:None)
+ self.read, self.write = os.pipe()
+ flags = fcntl.fcntl(self.write, fcntl.F_GETFL, 0)
+ flags = flags | os.O_NONBLOCK
+ fcntl.fcntl(self.write, fcntl.F_SETFL, flags)
+ self.old_wakeup = signal.set_wakeup_fd(self.write)
+
+ def tearDown(self):
+ signal.set_wakeup_fd(self.old_wakeup)
+ os.close(self.read)
+ os.close(self.write)
+ signal.signal(signal.SIGALRM, self.alrm)
+
+
def test_main():
if sys.platform[:3] in ('win', 'os2') or sys.platform == 'riscos':
raise test_support.TestSkipped("Can't test signal on %s" % \
sys.platform)
- test_support.run_unittest(BasicSignalTests, InterProcessSignalTests)
+ test_support.run_unittest(BasicSignalTests, InterProcessSignalTests,
+ WakeupSignalTests)
if __name__ == "__main__":