cpython/Lib/test/test_signal.py

144 lines
3.9 KiB
Python

# Test the signal module
from test.test_support import verbose, TestSkipped, TestFailed, vereq
import signal
import os, sys, time
if sys.platform[:3] in ('win', 'os2') or sys.platform=='riscos':
raise TestSkipped, "Can't test signal on %s" % sys.platform
if verbose:
x = '-x'
else:
x = '+x'
pid = os.getpid()
# Shell script that will send us asynchronous signals
script = """
(
set %(x)s
sleep 2
kill -HUP %(pid)d
sleep 2
kill -USR1 %(pid)d
sleep 2
kill -USR2 %(pid)d
) &
""" % vars()
a_called = b_called = False
def handlerA(*args):
global a_called
a_called = True
if verbose:
print "handlerA", args
class HandlerBCalled(Exception):
pass
def handlerB(*args):
global b_called
b_called = True
if verbose:
print "handlerB", args
raise HandlerBCalled, args
MAX_DURATION = 20
signal.alarm(MAX_DURATION) # Entire test should last at most 20 sec.
hup = signal.signal(signal.SIGHUP, handlerA)
usr1 = signal.signal(signal.SIGUSR1, handlerB)
usr2 = signal.signal(signal.SIGUSR2, signal.SIG_IGN)
alrm = signal.signal(signal.SIGALRM, signal.default_int_handler)
vereq(signal.getsignal(signal.SIGHUP), handlerA)
vereq(signal.getsignal(signal.SIGUSR1), handlerB)
vereq(signal.getsignal(signal.SIGUSR2), signal.SIG_IGN)
try:
signal.signal(4242, handlerB)
raise TestFailed, 'expected ValueError for invalid signal # to signal()'
except ValueError:
pass
try:
signal.getsignal(4242)
raise TestFailed, 'expected ValueError for invalid signal # to getsignal()'
except ValueError:
pass
try:
signal.signal(signal.SIGUSR1, None)
raise TestFailed, 'expected TypeError for non-callable'
except TypeError:
pass
# Set up a child to send an alarm signal to us (the parent) after waiting
# long enough to receive the alarm. It seems we miss the alarm for some
# reason. This will hopefully stop the hangs on Tru64/Alpha.
def force_test_exit():
# Sigh, both imports seem necessary to avoid errors.
import os
fork_pid = os.fork()
if fork_pid == 0:
# In child
import os, time
try:
# Wait 5 seconds longer than the expected alarm to give enough
# time for the normal sequence of events to occur. This is
# just a stop-gap to prevent the test from hanging.
time.sleep(MAX_DURATION + 5)
for i in range(3):
os.kill(pid, signal.SIGALARM)
finally:
os._exit(0)
# In parent (or error)
return fork_pid
try:
os.system(script)
# Try to ensure this test exits even if there is some problem with alarm.
# Tru64/Alpha sometimes hangs and is ultimately killed by the buildbot.
fork_pid = force_test_exit()
print "starting pause() loop..."
try:
while 1:
if verbose:
print "call pause()..."
try:
signal.pause()
if verbose:
print "pause() returned"
except HandlerBCalled:
if verbose:
print "HandlerBCalled exception caught"
else:
pass
except KeyboardInterrupt:
if verbose:
print "KeyboardInterrupt (assume the alarm() went off)"
# Forcibly kill the child we created to ping us if there was a test error.
try:
# Make sure we don't kill ourself if there was a fork error.
if fork_pid > 0:
os.kill(fork_pid, signal.SIGKILL)
except:
# If the child killed us, it has probably exited. Killing a
# non-existant process will raise an error which we don't care about.
pass
if not a_called:
print 'HandlerA not called'
if not b_called:
print 'HandlerB not called'
finally:
signal.signal(signal.SIGHUP, hup)
signal.signal(signal.SIGUSR1, usr1)
signal.signal(signal.SIGUSR2, usr2)
signal.signal(signal.SIGALRM, alrm)