import enum
import errno
import functools
import inspect
import os
import random
import signal
import socket
import statistics
import subprocess
import sys
import threading
import time
import unittest
from test import support
from test.support import (
is_apple, is_apple_mobile, os_helper, threading_helper
)
from test.support.script_helper import assert_python_ok, spawn_python
try:
import _testcapi
except ImportError:
_testcapi = None
class GenericTests(unittest.TestCase):
def test_enums(self):
for name in dir(signal):
sig = getattr(signal, name)
if name in {'SIG_DFL', 'SIG_IGN'}:
self.assertIsInstance(sig, signal.Handlers)
elif name in {'SIG_BLOCK', 'SIG_UNBLOCK', 'SIG_SETMASK'}:
self.assertIsInstance(sig, signal.Sigmasks)
elif name.startswith('SIG') and not name.startswith('SIG_'):
self.assertIsInstance(sig, signal.Signals)
elif name.startswith('CTRL_'):
self.assertIsInstance(sig, signal.Signals)
self.assertEqual(sys.platform, "win32")
CheckedSignals = enum._old_convert_(
enum.IntEnum, 'Signals', 'signal',
lambda name:
name.isupper()
and (name.startswith('SIG') and not name.startswith('SIG_'))
or name.startswith('CTRL_'),
source=signal,
)
enum._test_simple_enum(CheckedSignals, signal.Signals)
CheckedHandlers = enum._old_convert_(
enum.IntEnum, 'Handlers', 'signal',
lambda name: name in ('SIG_DFL', 'SIG_IGN'),
source=signal,
)
enum._test_simple_enum(CheckedHandlers, signal.Handlers)
Sigmasks = getattr(signal, 'Sigmasks', None)
if Sigmasks is not None:
CheckedSigmasks = enum._old_convert_(
enum.IntEnum, 'Sigmasks', 'signal',
lambda name: name in ('SIG_BLOCK', 'SIG_UNBLOCK', 'SIG_SETMASK'),
source=signal,
)
enum._test_simple_enum(CheckedSigmasks, Sigmasks)
def test_functions_module_attr(self):
# Issue #27718: If __all__ is not defined all non-builtin functions
# should have correct __module__ to be displayed by pydoc.
for name in dir(signal):
value = getattr(signal, name)
if inspect.isroutine(value) and not inspect.isbuiltin(value):
self.assertEqual(value.__module__, 'signal')
@unittest.skipIf(sys.platform == "win32", "Not valid on Windows")
class PosixTests(unittest.TestCase):
def trivial_signal_handler(self, *args):
pass
def create_handler_with_partial(self, argument):
return functools.partial(self.trivial_signal_handler, argument)
def test_out_of_range_signal_number_raises_error(self):
self.assertRaises(ValueError, signal.getsignal, 4242)
self.assertRaises(ValueError, signal.signal, 4242,
self.trivial_signal_handler)
self.assertRaises(ValueError, signal.strsignal, 4242)
def test_setting_signal_handler_to_none_raises_error(self):
self.assertRaises(TypeError, signal.signal,
signal.SIGUSR1, None)
def test_getsignal(self):
hup = signal.signal(signal.SIGHUP, self.trivial_signal_handler)
self.assertIsInstance(hup, signal.Handlers)
self.assertEqual(signal.getsignal(signal.SIGHUP),
self.trivial_signal_handler)
signal.signal(signal.SIGHUP, hup)
self.assertEqual(signal.getsignal(signal.SIGHUP), hup)
def test_no_repr_is_called_on_signal_handler(self):
# See https://github.com/python/cpython/issues/112559.
class MyArgument:
def __init__(self):
self.repr_count = 0
def __repr__(self):
self.repr_count += 1
return super().__repr__()
argument = MyArgument()
self.assertEqual(0, argument.repr_count)
handler = self.create_handler_with_partial(argument)
hup = signal.signal(signal.SIGHUP, handler)
self.assertIsInstance(hup, signal.Handlers)
self.assertEqual(signal.getsignal(signal.SIGHUP), handler)
signal.signal(signal.SIGHUP, hup)
self.assertEqual(signal.getsignal(signal.SIGHUP), hup)
self.assertEqual(0, argument.repr_count)
@unittest.skipIf(sys.platform.startswith("netbsd"),
"gh-124083: strsignal is not supported on NetBSD")
def test_strsignal(self):
self.assertIn("Interrupt", signal.strsignal(signal.SIGINT))
self.assertIn("Terminated", signal.strsignal(signal.SIGTERM))
self.assertIn("Hangup", signal.strsignal(signal.SIGHUP))
# Issue 3864, unknown if this affects earlier versions of freebsd also
def test_interprocess_signal(self):
dirname = os.path.dirname(__file__)
script = os.path.join(dirname, 'signalinterproctester.py')
assert_python_ok(script)
@unittest.skipUnless(
hasattr(signal, "valid_signals"),
"requires signal.valid_signals"
)
def test_valid_signals(self):
s = signal.valid_signals()
self.assertIsInstance(s, set)
self.assertIn(signal.Signals.SIGINT, s)
self.assertIn(signal.Signals.SIGALRM, s)
self.assertNotIn(0, s)
self.assertNotIn(signal.NSIG, s)
self.assertLess(len(s), signal.NSIG)
# gh-91145: Make sure that all SIGxxx constants exposed by the Python
# signal module have a number in the [0; signal.NSIG-1] range.
for name in dir(signal):
if not name.startswith("SIG"):
continue
if name in {"SIG_IGN", "SIG_DFL"}:
# SIG_IGN and SIG_DFL are pointers
continue
with self.subTest(name=name):
signum = getattr(signal, name)
self.assertGreaterEqual(signum, 0)
self.assertLess(signum, signal.NSIG)
@unittest.skipUnless(sys.executable, "sys.executable required.")
@support.requires_subprocess()
def test_keyboard_interrupt_exit_code(self):
"""KeyboardInterrupt triggers exit via SIGINT."""
process = subprocess.run(
[sys.executable, "-c",
"import os, signal, time\n"
"os.kill(os.getpid(), signal.SIGINT)\n"
"for _ in range(999): time.sleep(0.01)"],
stderr=subprocess.PIPE)
self.assertIn(b"KeyboardInterrupt", process.stderr)
self.assertEqual(process.returncode, -signal.SIGINT)
# Caveat: The exit code is insufficient to guarantee we actually died
# via a signal. POSIX shells do more than look at the 8 bit value.
# Writing an automation friendly test of an interactive shell
# to confirm that our process died via a SIGINT proved too complex.
@unittest.skipUnless(sys.platform == "win32", "Windows specific")
class WindowsSignalTests(unittest.TestCase):
def test_valid_signals(self):
s = signal.valid_signals()
self.assertIsInstance(s, set)
self.assertGreaterEqual(len(s), 6)
self.assertIn(signal.Signals.SIGINT, s)
self.assertNotIn(0, s)
self.assertNotIn(signal.NSIG, s)
self.assertLess(len(s), signal.NSIG)
def test_issue9324(self):
# Updated for issue #10003, adding SIGBREAK
handler = lambda x, y: None
checked = set()
for sig in (signal.SIGABRT, signal.SIGBREAK, signal.SIGFPE,
signal.SIGILL, signal.SIGINT, signal.SIGSEGV,
signal.SIGTERM):
# Set and then reset a handler for signals that work on windows.
# Issue #18396, only for signals without a C-level handler.
if signal.getsignal(sig) is not None:
signal.signal(sig, signal.signal(sig, handler))
checked.add(sig)
# Issue #18396: Ensure the above loop at least tested *something*
self.assertTrue(checked)
with self.assertRaises(ValueError):
signal.signal(-1, handler)
with self.assertRaises(ValueError):
signal.signal(7, handler)
@unittest.skipUnless(sys.executable, "sys.executable required.")
@support.requires_subprocess()
def test_keyboard_interrupt_exit_code(self):
"""KeyboardInterrupt triggers an exit using STATUS_CONTROL_C_EXIT."""
# We don't test via os.kill(os.getpid(), signal.CTRL_C_EVENT) here
# as that requires setting up a console control handler in a child
# in its own process group. Doable, but quite complicated. (see
# @eryksun on https://github.com/python/cpython/pull/11862)
process = subprocess.run(
[sys.executable, "-c", "raise KeyboardInterrupt"],
stderr=subprocess.PIPE)
self.assertIn(b"KeyboardInterrupt", process.stderr)
STATUS_CONTROL_C_EXIT = 0xC000013A
self.assertEqual(process.returncode, STATUS_CONTROL_C_EXIT)
class WakeupFDTests(unittest.TestCase):
def test_invalid_call(self):
# First parameter is positional-only
with self.assertRaises(TypeError):
signal.set_wakeup_fd(signum=signal.SIGINT)
# warn_on_full_buffer is a keyword-only parameter
with self.assertRaises(TypeError):
signal.set_wakeup_fd(signal.SIGINT, False)
def test_invalid_fd(self):
fd = os_helper.make_bad_fd()
self.assertRaises((ValueError, OSError),
signal.set_wakeup_fd, fd)
@unittest.skipUnless(support.has_socket_support, "needs working sockets.")
def test_invalid_socket(self):
sock = socket.socket()
fd = sock.fileno()
sock.close()
self.assertRaises((ValueError, OSError),
signal.set_wakeup_fd, fd)
# Emscripten does not support fstat on pipes yet.
# https://github.com/emscripten-core/emscripten/issues/16414
@unittest.skipIf(support.is_emscripten, "Emscripten cannot fstat pipes.")
@unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
def test_set_wakeup_fd_result(self):
r1, w1 = os.pipe()
self.addCleanup(os.close, r1)
self.addCleanup(os.close, w1)
r2, w2 = os.pipe()
self.addCleanup(os.close, r2)
self.addCleanup(os.close, w2)
if hasattr(os, 'set_blocking'):
os.set_blocking(w1, False)
os.set_blocking(w2, False)
signal.set_wakeup_fd(w1)
self.assertEqual(signal.set_wakeup_fd(w2), w1)
self.assertEqual(signal.set_wakeup_fd(-1), w2)
self.assertEqual(signal.set_wakeup_fd(-1), -1)
@unittest.skipIf(support.is_emscripten, "Emscripten cannot fstat pipes.")
@unittest.skipUnless(support.has_socket_support, "needs working sockets.")
def test_set_wakeup_fd_socket_result(self):
sock1 = socket.socket()
self.addCleanup(sock1.close)
sock1.setblocking(False)
fd1 = sock1.fileno()
sock2 = socket.socket()
self.addCleanup(sock2.close)
sock2.setblocking(False)
fd2 = sock2.fileno()
signal.set_wakeup_fd(fd1)
self.assertEqual(signal.set_wakeup_fd(fd2), fd1)
self.assertEqual(signal.set_wakeup_fd(-1), fd2)
self.assertEqual(signal.set_wakeup_fd(-1), -1)
# On Windows, files are always blocking and Windows does not provide a
# function to test if a socket is in non-blocking mode.
@unittest.skipIf(sys.platform == "win32", "tests specific to POSIX")
@unittest.skipIf(support.is_emscripten, "Emscripten cannot fstat pipes.")
@unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
def test_set_wakeup_fd_blocking(self):
rfd, wfd = os.pipe()
self.addCleanup(os.close, rfd)
self.addCleanup(os.close, wfd)
# fd must be non-blocking
os.set_blocking(wfd, True)
with self.assertRaises(ValueError) as cm:
signal.set_wakeup_fd(wfd)
self.assertEqual(str(cm.exception),
"the fd %s must be in non-blocking mode" % wfd)
# non-blocking is ok
os.set_blocking(wfd, False)
signal.set_wakeup_fd(wfd)
signal.set_wakeup_fd(-1)
@unittest.skipIf(sys.platform == "win32", "Not valid on Windows")
class WakeupSignalTests(unittest.TestCase):
@unittest.skipIf(_testcapi is None, 'need _testcapi')
def check_wakeup(self, test_body, *signals, ordered=True):
# use a subprocess to have only one thread
code = """if 1:
import _testcapi
import os
import signal
import struct
signals = {!r}
def handler(signum, frame):
pass
def check_signum(signals):
data = os.read(read, len(signals)+1)
raised = struct.unpack('%uB' % len(data), data)
if not {!r}:
raised = set(raised)
signals = set(signals)
if raised != signals:
raise Exception("%r != %r" % (raised, signals))
{}
signal.signal(signal.SIGALRM, handler)
read, write = os.pipe()
os.set_blocking(write, False)
signal.set_wakeup_fd(write)
test()
check_signum(signals)
os.close(read)
os.close(write)
""".format(tuple(map(int, signals)), ordered, test_body)
assert_python_ok('-c', code)
@unittest.skipIf(_testcapi is None, 'need _testcapi')
@unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
def test_wakeup_write_error(self):
# Issue #16105: write() errors in the C signal handler should not
# pass silently.
# Use a subprocess to have only one thread.
code = """if 1:
import _testcapi
import errno
import os
import signal
import sys
from test.support import captured_stderr
def handler(signum, frame):
1/0
signal.signal(signal.SIGALRM, handler)
r, w = os.pipe()
os.set_blocking(r, False)
# Set wakeup_fd a read-only file descriptor to trigger the error
signal.set_wakeup_fd(r)
try:
with captured_stderr() as err:
signal.raise_signal(signal.SIGALRM)
except ZeroDivisionError:
# An ignored exception should have been printed out on stderr
err = err.getvalue()
if ('Exception ignored when trying to write to the signal wakeup fd'
not in err):
raise AssertionError(err)
if ('OSError: [Errno %d]' % errno.EBADF) not in err:
raise AssertionError(err)
else:
raise AssertionError("ZeroDivisionError not raised")
os.close(r)
os.close(w)
"""
r, w = os.pipe()
try:
os.write(r, b'x')
except OSError:
pass
else:
self.skipTest("OS doesn't report write() error on the read end of a pipe")
finally:
os.close(r)
os.close(w)
assert_python_ok('-c', code)
def test_wakeup_fd_early(self):
self.check_wakeup("""def test():
import select
import time
TIMEOUT_FULL = 10
TIMEOUT_HALF = 5
class InterruptSelect(Exception):
pass
def handler(signum, frame):
raise InterruptSelect
signal.signal(signal.SIGALRM, handler)
signal.alarm(1)
# We attempt to get a signal during the sleep,
# before select is called
try:
select.select([], [], [], TIMEOUT_FULL)
except InterruptSelect:
pass
else:
raise Exception("select() was not interrupted")
before_time = time.monotonic()
select.select([read], [], [], TIMEOUT_FULL)
after_time = time.monotonic()
dt = after_time - before_time
if dt >= TIMEOUT_HALF:
raise Exception("%s >= %s" % (dt, TIMEOUT_HALF))
""", signal.SIGALRM)
def test_wakeup_fd_during(self):
self.check_wakeup("""def test():
import select
import time
TIMEOUT_FULL = 10
TIMEOUT_HALF = 5
class InterruptSelect(Exception):
pass
def handler(signum, frame):
raise InterruptSelect
signal.signal(signal.SIGALRM, handler)
signal.alarm(1)
before_time = time.monotonic()
# We attempt to get a signal during the select call
try:
select.select([read], [], [], TIMEOUT_FULL)
except InterruptSelect:
pass
else:
raise Exception("select() was not interrupted")
after_time = time.monotonic()
dt = after_time - before_time
if dt >= TIMEOUT_HALF:
raise Exception("%s >= %s" % (dt, TIMEOUT_HALF))
""", signal.SIGALRM)
def test_signum(self):
self.check_wakeup("""def test():
signal.signal(signal.SIGUSR1, handler)
signal.raise_signal(signal.SIGUSR1)
signal.raise_signal(signal.SIGALRM)
""", signal.SIGUSR1, signal.SIGALRM)
@unittest.skipUnless(hasattr(signal, 'pthread_sigmask'),
'need signal.pthread_sigmask()')
def test_pending(self):
self.check_wakeup("""def test():
signum1 = signal.SIGUSR1
signum2 = signal.SIGUSR2
signal.signal(signum1, handler)
signal.signal(signum2, handler)
signal.pthread_sigmask(signal.SIG_BLOCK, (signum1, signum2))
signal.raise_signal(signum1)
signal.raise_signal(signum2)
# Unblocking the 2 signals calls the C signal handler twice
signal.pthread_sigmask(signal.SIG_UNBLOCK, (signum1, signum2))
""", signal.SIGUSR1, signal.SIGUSR2, ordered=False)
@unittest.skipUnless(hasattr(socket, 'socketpair'), 'need socket.socketpair')
class WakeupSocketSignalTests(unittest.TestCase):
@unittest.skipIf(_testcapi is None, 'need _testcapi')
def test_socket(self):
# use a subprocess to have only one thread
code = """if 1:
import signal
import socket
import struct
import _testcapi
signum = signal.SIGINT
signals = (signum,)
def handler(signum, frame):
pass
signal.signal(signum, handler)
read, write = socket.socketpair()
write.setblocking(False)
signal.set_wakeup_fd(write.fileno())
signal.raise_signal(signum)
data = read.recv(1)
if not data:
raise Exception("no signum written")
raised = struct.unpack('B', data)
if raised != signals:
raise Exception("%r != %r" % (raised, signals))
read.close()
write.close()
"""
assert_python_ok('-c', code)
@unittest.skipIf(_testcapi is None, 'need _testcapi')
def test_send_error(self):
# Use a subprocess to have only one thread.
if os.name == 'nt':
action = 'send'
else:
action = 'write'
code = """if 1:
import errno
import signal
import socket
import sys
import time
import _testcapi
from test.support import captured_stderr
signum = signal.SIGINT
def handler(signum, frame):
pass
signal.signal(signum, handler)
read, write = socket.socketpair()
read.setblocking(False)
write.setblocking(False)
signal.set_wakeup_fd(write.fileno())
# Close sockets: send() will fail
read.close()
write.close()
with captured_stderr() as err:
signal.raise_signal(signum)
err = err.getvalue()
if ('Exception ignored when trying to {action} to the signal wakeup fd'
not in err):
raise AssertionError(err)
""".format(action=action)
assert_python_ok('-c', code)
@unittest.skipIf(_testcapi is None, 'need _testcapi')
def test_warn_on_full_buffer(self):
# Use a subprocess to have only one thread.
if os.name == 'nt':
action = 'send'
else:
action = 'write'
code = """if 1:
import errno
import signal
import socket
import sys
import time
import _testcapi
from test.support import captured_stderr
signum = signal.SIGINT
# This handler will be called, but we intentionally won't read from
# the wakeup fd.
def handler(signum, frame):
pass
signal.signal(signum, handler)
read, write = socket.socketpair()
# Fill the socketpair buffer
if sys.platform == 'win32':
# bpo-34130: On Windows, sometimes non-blocking send fails to fill
# the full socketpair buffer, so use a timeout of 50 ms instead.
write.settimeout(0.050)
else:
write.setblocking(False)
written = 0
if sys.platform == "vxworks":
CHUNK_SIZES = (1,)
else:
# Start with large chunk size to reduce the
# number of send needed to fill the buffer.
CHUNK_SIZES = (2 ** 16, 2 ** 8, 1)
for chunk_size in CHUNK_SIZES:
chunk = b"x" * chunk_size
try:
while True:
write.send(chunk)
written += chunk_size
except (BlockingIOError, TimeoutError):
pass
print(f"%s bytes written into the socketpair" % written, flush=True)
write.setblocking(False)
try:
write.send(b"x")
except BlockingIOError:
# The socketpair buffer seems full
pass
else:
raise AssertionError("%s bytes failed to fill the socketpair "
"buffer" % written)
# By default, we get a warning when a signal arrives
msg = ('Exception ignored when trying to {action} '
'to the signal wakeup fd')
signal.set_wakeup_fd(write.fileno())
with captured_stderr() as err:
signal.raise_signal(signum)
err = err.getvalue()
if msg not in err:
raise AssertionError("first set_wakeup_fd() test failed, "
"stderr: %r" % err)
# And also if warn_on_full_buffer=True
signal.set_wakeup_fd(write.fileno(), warn_on_full_buffer=True)
with captured_stderr() as err:
signal.raise_signal(signum)
err = err.getvalue()
if msg not in err:
raise AssertionError("set_wakeup_fd(warn_on_full_buffer=True) "
"test failed, stderr: %r" % err)
# But not if warn_on_full_buffer=False
signal.set_wakeup_fd(write.fileno(), warn_on_full_buffer=False)
with captured_stderr() as err:
signal.raise_signal(signum)
err = err.getvalue()
if err != "":
raise AssertionError("set_wakeup_fd(warn_on_full_buffer=False) "
"test failed, stderr: %r" % err)
# And then check the default again, to make sure warn_on_full_buffer
# settings don't leak across calls.
signal.set_wakeup_fd(write.fileno())
with captured_stderr() as err:
signal.raise_signal(signum)
err = err.getvalue()
if msg not in err:
raise AssertionError("second set_wakeup_fd() test failed, "
"stderr: %r" % err)
""".format(action=action)
assert_python_ok('-c', code)
@unittest.skipIf(sys.platform == "win32", "Not valid on Windows")
@unittest.skipUnless(hasattr(signal, 'siginterrupt'), "needs signal.siginterrupt()")
@support.requires_subprocess()
@unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
class SiginterruptTest(unittest.TestCase):
def readpipe_interrupted(self, interrupt, timeout=support.SHORT_TIMEOUT):
"""Perform a read during which a signal will arrive. Return True if the
read is interrupted by the signal and raises an exception. Return False
if it returns normally.
"""
# use a subprocess to have only one thread, to have a timeout on the
# blocking read and to not touch signal handling in this process
code = """if 1:
import errno
import os
import signal
import sys
interrupt = %r
r, w = os.pipe()
def handler(signum, frame):
1 / 0
signal.signal(signal.SIGALRM, handler)
if interrupt is not None:
signal.siginterrupt(signal.SIGALRM, interrupt)
print("ready")
sys.stdout.flush()
# run the test twice
try:
for loop in range(2):
# send a SIGALRM in a second (during the read)
signal.alarm(1)
try:
# blocking call: read from a pipe without data
os.read(r, 1)
except ZeroDivisionError:
pass
else:
sys.exit(2)
sys.exit(3)
finally:
os.close(r)
os.close(w)
""" % (interrupt,)
with spawn_python('-c', code) as process:
try:
# wait until the child process is loaded and has started
first_line = process.stdout.readline()
stdout, stderr = process.communicate(timeout=timeout)
except subprocess.TimeoutExpired:
process.kill()
return False
else:
stdout = first_line + stdout
exitcode = process.wait()
if exitcode not in (2, 3):
raise Exception("Child error (exit code %s): %r"
% (exitcode, stdout))
return (exitcode == 3)
def test_without_siginterrupt(self):
# If a signal handler is installed and siginterrupt is not called
# at all, when that signal arrives, it interrupts a syscall that's in
# progress.
interrupted = self.readpipe_interrupted(None)
self.assertTrue(interrupted)
def test_siginterrupt_on(self):
# If a signal handler is installed and siginterrupt is called with
# a true value for the second argument, when that signal arrives, it
# interrupts a syscall that's in progress.
interrupted = self.readpipe_interrupted(True)
self.assertTrue(interrupted)
@support.requires_resource('walltime')
def test_siginterrupt_off(self):
# If a signal handler is installed and siginterrupt is called with
# a false value for the second argument, when that signal arrives, it
# does not interrupt a syscall that's in progress.
interrupted = self.readpipe_interrupted(False, timeout=2)
self.assertFalse(interrupted)
@unittest.skipIf(sys.platform == "win32", "Not valid on Windows")
@unittest.skipUnless(hasattr(signal, 'getitimer') and hasattr(signal, 'setitimer'),
"needs signal.getitimer() and signal.setitimer()")
class ItimerTest(unittest.TestCase):
def setUp(self):
self.hndl_called = False
self.hndl_count = 0
self.itimer = None
self.old_alarm = signal.signal(signal.SIGALRM, self.sig_alrm)
def tearDown(self):
signal.signal(signal.SIGALRM, self.old_alarm)
if self.itimer is not None: # test_itimer_exc doesn't change this attr
# just ensure that itimer is stopped
signal.setitimer(self.itimer, 0)
def sig_alrm(self, *args):
self.hndl_called = True
def sig_vtalrm(self, *args):
self.hndl_called = True
if self.hndl_count > 3:
# it shouldn't be here, because it should have been disabled.
raise signal.ItimerError("setitimer didn't disable ITIMER_VIRTUAL "
"timer.")
elif self.hndl_count == 3:
# disable ITIMER_VIRTUAL, this function shouldn't be called anymore
signal.setitimer(signal.ITIMER_VIRTUAL, 0)
self.hndl_count += 1
def sig_prof(self, *args):
self.hndl_called = True
signal.setitimer(signal.ITIMER_PROF, 0)
def test_itimer_exc(self):
# XXX I'm assuming -1 is an invalid itimer, but maybe some platform
# defines it ?
self.assertRaises(signal.ItimerError, signal.setitimer, -1, 0)
# Negative times are treated as zero on some platforms.
if 0:
self.assertRaises(signal.ItimerError,
signal.setitimer, signal.ITIMER_REAL, -1)
def test_itimer_real(self):
self.itimer = signal.ITIMER_REAL
signal.setitimer(self.itimer, 1.0)
signal.pause()
self.assertEqual(self.hndl_called, True)
# Issue 3864, unknown if this affects earlier versions of freebsd also
@unittest.skipIf(sys.platform in ('netbsd5',) or is_apple_mobile,
'itimer not reliable (does not mix well with threading) on some BSDs.')
def test_itimer_virtual(self):
self.itimer = signal.ITIMER_VIRTUAL
signal.signal(signal.SIGVTALRM, self.sig_vtalrm)
signal.setitimer(self.itimer, 0.3, 0.2)
for _ in support.busy_retry(support.LONG_TIMEOUT):
# use up some virtual time by doing real work
_ = pow(12345, 67890, 10000019)
if signal.getitimer(self.itimer) == (0.0, 0.0):
# sig_vtalrm handler stopped this itimer
break
# virtual itimer should be (0.0, 0.0) now
self.assertEqual(signal.getitimer(self.itimer), (0.0, 0.0))
# and the handler should have been called
self.assertEqual(self.hndl_called, True)
def test_itimer_prof(self):
self.itimer = signal.ITIMER_PROF
signal.signal(signal.SIGPROF, self.sig_prof)
signal.setitimer(self.itimer, 0.2, 0.2)
for _ in support.busy_retry(support.LONG_TIMEOUT):
# do some work
_ = pow(12345, 67890, 10000019)
if signal.getitimer(self.itimer) == (0.0, 0.0):
# sig_prof handler stopped this itimer
break
# profiling itimer should be (0.0, 0.0) now
self.assertEqual(signal.getitimer(self.itimer), (0.0, 0.0))
# and the handler should have been called
self.assertEqual(self.hndl_called, True)
def test_setitimer_tiny(self):
# bpo-30807: C setitimer() takes a microsecond-resolution interval.
# Check that float -> timeval conversion doesn't round
# the interval down to zero, which would disable the timer.
self.itimer = signal.ITIMER_REAL
signal.setitimer(self.itimer, 1e-6)
time.sleep(1)
self.assertEqual(self.hndl_called, True)
class PendingSignalsTests(unittest.TestCase):
"""
Test pthread_sigmask(), pthread_kill(), sigpending() and sigwait()
functions.
"""
@unittest.skipUnless(hasattr(signal, 'sigpending'),
'need signal.sigpending()')
def test_sigpending_empty(self):
self.assertEqual(signal.sigpending(), set())
@unittest.skipUnless(hasattr(signal, 'pthread_sigmask'),
'need signal.pthread_sigmask()')
@unittest.skipUnless(hasattr(signal, 'sigpending'),
'need signal.sigpending()')
def test_sigpending(self):
code = """if 1:
import os
import signal
def handler(signum, frame):
1/0
signum = signal.SIGUSR1
signal.signal(signum, handler)
signal.pthread_sigmask(signal.SIG_BLOCK, [signum])
os.kill(os.getpid(), signum)
pending = signal.sigpending()
for sig in pending:
assert isinstance(sig, signal.Signals), repr(pending)
if pending != {signum}:
raise Exception('%s != {%s}' % (pending, signum))
try:
signal.pthread_sigmask(signal.SIG_UNBLOCK, [signum])
except ZeroDivisionError:
pass
else:
raise Exception("ZeroDivisionError not raised")
"""
assert_python_ok('-c', code)
@unittest.skipUnless(hasattr(signal, 'pthread_kill'),
'need signal.pthread_kill()')
@threading_helper.requires_working_threading()
def test_pthread_kill(self):
code = """if 1:
import signal
import threading
import sys
signum = signal.SIGUSR1
def handler(signum, frame):
1/0
signal.signal(signum, handler)
tid = threading.get_ident()
try:
signal.pthread_kill(tid, signum)
except ZeroDivisionError:
pass
else:
raise Exception("ZeroDivisionError not raised")
"""
assert_python_ok('-c', code)
@unittest.skipUnless(hasattr(signal, 'pthread_sigmask'),
'need signal.pthread_sigmask()')
def wait_helper(self, blocked, test):
"""
test: body of the "def test(signum):" function.
blocked: number of the blocked signal
"""
code = '''if 1:
import signal
import sys
from signal import Signals
def handler(signum, frame):
1/0
%s
blocked = %s
signum = signal.SIGALRM
# child: block and wait the signal
try:
signal.signal(signum, handler)
signal.pthread_sigmask(signal.SIG_BLOCK, [blocked])
# Do the tests
test(signum)
# The handler must not be called on unblock
try:
signal.pthread_sigmask(signal.SIG_UNBLOCK, [blocked])
except ZeroDivisionError:
print("the signal handler has been called",
file=sys.stderr)
sys.exit(1)
except BaseException as err:
print("error: {}".format(err), file=sys.stderr)
sys.stderr.flush()
sys.exit(1)
''' % (test.strip(), blocked)
# sig*wait* must be called with the signal blocked: since the current
# process might have several threads running, use a subprocess to have
# a single thread.
assert_python_ok('-c', code)
@unittest.skipUnless(hasattr(signal, 'sigwait'),
'need signal.sigwait()')
def test_sigwait(self):
self.wait_helper(signal.SIGALRM, '''
def test(signum):
signal.alarm(1)
received = signal.sigwait([signum])
assert isinstance(received, signal.Signals), received
if received != signum:
raise Exception('received %s, not %s' % (received, signum))
''')
@unittest.skipUnless(hasattr(signal, 'sigwaitinfo'),
'need signal.sigwaitinfo()')
def test_sigwaitinfo(self):
self.wait_helper(signal.SIGALRM, '''
def test(signum):
signal.alarm(1)
info = signal.sigwaitinfo([signum])
if info.si_signo != signum:
raise Exception("info.si_signo != %s" % signum)
''')
@unittest.skipUnless(hasattr(signal, 'sigtimedwait'),
'need signal.sigtimedwait()')
def test_sigtimedwait(self):
self.wait_helper(signal.SIGALRM, '''
def test(signum):
signal.alarm(1)
info = signal.sigtimedwait([signum], 10.1000)
if info.si_signo != signum:
raise Exception('info.si_signo != %s' % signum)
''')
@unittest.skipUnless(hasattr(signal, 'sigtimedwait'),
'need signal.sigtimedwait()')
def test_sigtimedwait_poll(self):
# check that polling with sigtimedwait works
self.wait_helper(signal.SIGALRM, '''
def test(signum):
import os
os.kill(os.getpid(), signum)
info = signal.sigtimedwait([signum], 0)
if info.si_signo != signum:
raise Exception('info.si_signo != %s' % signum)
''')
@unittest.skipUnless(hasattr(signal, 'sigtimedwait'),
'need signal.sigtimedwait()')
def test_sigtimedwait_timeout(self):
self.wait_helper(signal.SIGALRM, '''
def test(signum):
received = signal.sigtimedwait([signum], 1.0)
if received is not None:
raise Exception("received=%r" % (received,))
''')
@unittest.skipUnless(hasattr(signal, 'sigtimedwait'),
'need signal.sigtimedwait()')
def test_sigtimedwait_negative_timeout(self):
signum = signal.SIGALRM
self.assertRaises(ValueError, signal.sigtimedwait, [signum], -1.0)
@unittest.skipUnless(hasattr(signal, 'sigwait'),
'need signal.sigwait()')
@unittest.skipUnless(hasattr(signal, 'pthread_sigmask'),
'need signal.pthread_sigmask()')
@threading_helper.requires_working_threading()
def test_sigwait_thread(self):
# Check that calling sigwait() from a thread doesn't suspend the whole
# process. A new interpreter is spawned to avoid problems when mixing
# threads and fork(): only async-safe functions are allowed between
# fork() and exec().
assert_python_ok("-c", """if True:
import os, threading, sys, time, signal
# the default handler terminates the process
signum = signal.SIGUSR1
def kill_later():
# wait until the main thread is waiting in sigwait()
time.sleep(1)
os.kill(os.getpid(), signum)
# the signal must be blocked by all the threads
signal.pthread_sigmask(signal.SIG_BLOCK, [signum])
killer = threading.Thread(target=kill_later)
killer.start()
received = signal.sigwait([signum])
if received != signum:
print("sigwait() received %s, not %s" % (received, signum),
file=sys.stderr)
sys.exit(1)
killer.join()
# unblock the signal, which should have been cleared by sigwait()
signal.pthread_sigmask(signal.SIG_UNBLOCK, [signum])
""")
@unittest.skipUnless(hasattr(signal, 'pthread_sigmask'),
'need signal.pthread_sigmask()')
def test_pthread_sigmask_arguments(self):
self.assertRaises(TypeError, signal.pthread_sigmask)
self.assertRaises(TypeError, signal.pthread_sigmask, 1)
self.assertRaises(TypeError, signal.pthread_sigmask, 1, 2, 3)
self.assertRaises(OSError, signal.pthread_sigmask, 1700, [])
with self.assertRaises(ValueError):
signal.pthread_sigmask(signal.SIG_BLOCK, [signal.NSIG])
with self.assertRaises(ValueError):
signal.pthread_sigmask(signal.SIG_BLOCK, [0])
with self.assertRaises(ValueError):
signal.pthread_sigmask(signal.SIG_BLOCK, [1<<1000])
@unittest.skipUnless(hasattr(signal, 'pthread_sigmask'),
'need signal.pthread_sigmask()')
def test_pthread_sigmask_valid_signals(self):
s = signal.pthread_sigmask(signal.SIG_BLOCK, signal.valid_signals())
self.addCleanup(signal.pthread_sigmask, signal.SIG_SETMASK, s)
# Get current blocked set
s = signal.pthread_sigmask(signal.SIG_UNBLOCK, signal.valid_signals())
self.assertLessEqual(s, signal.valid_signals())
@unittest.skipUnless(hasattr(signal, 'pthread_sigmask'),
'need signal.pthread_sigmask()')
@threading_helper.requires_working_threading()
def test_pthread_sigmask(self):
code = """if 1:
import signal
import os; import threading
def handler(signum, frame):
1/0
def kill(signum):
os.kill(os.getpid(), signum)
def check_mask(mask):
for sig in mask:
assert isinstance(sig, signal.Signals), repr(sig)
def read_sigmask():
sigmask = signal.pthread_sigmask(signal.SIG_BLOCK, [])
check_mask(sigmask)
return sigmask
signum = signal.SIGUSR1
# Install our signal handler
old_handler = signal.signal(signum, handler)
# Unblock SIGUSR1 (and copy the old mask) to test our signal handler
old_mask = signal.pthread_sigmask(signal.SIG_UNBLOCK, [signum])
check_mask(old_mask)
try:
kill(signum)
except ZeroDivisionError:
pass
else:
raise Exception("ZeroDivisionError not raised")
# Block and then raise SIGUSR1. The signal is blocked: the signal
# handler is not called, and the signal is now pending
mask = signal.pthread_sigmask(signal.SIG_BLOCK, [signum])
check_mask(mask)
kill(signum)
# Check the new mask
blocked = read_sigmask()
check_mask(blocked)
if signum not in blocked:
raise Exception("%s not in %s" % (signum, blocked))
if old_mask ^ blocked != {signum}:
raise Exception("%s ^ %s != {%s}" % (old_mask, blocked, signum))
# Unblock SIGUSR1
try:
# unblock the pending signal calls immediately the signal handler
signal.pthread_sigmask(signal.SIG_UNBLOCK, [signum])
except ZeroDivisionError:
pass
else:
raise Exception("ZeroDivisionError not raised")
try:
kill(signum)
except ZeroDivisionError:
pass
else:
raise Exception("ZeroDivisionError not raised")
# Check the new mask
unblocked = read_sigmask()
if signum in unblocked:
raise Exception("%s in %s" % (signum, unblocked))
if blocked ^ unblocked != {signum}:
raise Exception("%s ^ %s != {%s}" % (blocked, unblocked, signum))
if old_mask != unblocked:
raise Exception("%s != %s" % (old_mask, unblocked))
"""
assert_python_ok('-c', code)
@unittest.skipUnless(hasattr(signal, 'pthread_kill'),
'need signal.pthread_kill()')
@threading_helper.requires_working_threading()
def test_pthread_kill_main_thread(self):
# Test that a signal can be sent to the main thread with pthread_kill()
# before any other thread has been created (see issue #12392).
code = """if True:
import threading
import signal
import sys
def handler(signum, frame):
sys.exit(3)
signal.signal(signal.SIGUSR1, handler)
signal.pthread_kill(threading.get_ident(), signal.SIGUSR1)
sys.exit(2)
"""
with spawn_python('-c', code) as process:
stdout, stderr = process.communicate()
exitcode = process.wait()
if exitcode != 3:
raise Exception("Child error (exit code %s): %s" %
(exitcode, stdout))
class StressTest(unittest.TestCase):
"""
Stress signal delivery, especially when a signal arrives in
the middle of recomputing the signal state or executing
previously tripped signal handlers.
"""
def setsig(self, signum, handler):
old_handler = signal.signal(signum, handler)
self.addCleanup(signal.signal, signum, old_handler)
def measure_itimer_resolution(self):
N = 20
times = []
def handler(signum=None, frame=None):
if len(times) < N:
times.append(time.perf_counter())
# 1 µs is the smallest possible timer interval,
# we want to measure what the concrete duration
# will be on this platform
signal.setitimer(signal.ITIMER_REAL, 1e-6)
self.addCleanup(signal.setitimer, signal.ITIMER_REAL, 0)
self.setsig(signal.SIGALRM, handler)
handler()
while len(times) < N:
time.sleep(1e-3)
durations = [times[i+1] - times[i] for i in range(len(times) - 1)]
med = statistics.median(durations)
if support.verbose:
print("detected median itimer() resolution: %.6f s." % (med,))
return med
def decide_itimer_count(self):
# Some systems have poor setitimer() resolution (for example
# measured around 20 ms. on FreeBSD 9), so decide on a reasonable
# number of sequential timers based on that.
reso = self.measure_itimer_resolution()
if reso <= 1e-4:
return 10000
elif reso <= 1e-2:
return 100
else:
self.skipTest("detected itimer resolution (%.3f s.) too high "
"(> 10 ms.) on this platform (or system too busy)"
% (reso,))
@unittest.skipUnless(hasattr(signal, "setitimer"),
"test needs setitimer()")
def test_stress_delivery_dependent(self):
"""
This test uses dependent signal handlers.
"""
N = self.decide_itimer_count()
sigs = []
def first_handler(signum, frame):
# 1e-6 is the minimum non-zero value for `setitimer()`.
# Choose a random delay so as to improve chances of
# triggering a race condition. Ideally the signal is received
# when inside critical signal-handling routines such as
# Py_MakePendingCalls().
signal.setitimer(signal.ITIMER_REAL, 1e-6 + random.random() * 1e-5)
def second_handler(signum=None, frame=None):
sigs.append(signum)
# Here on Linux, SIGPROF > SIGALRM > SIGUSR1. By using both
# ascending and descending sequences (SIGUSR1 then SIGALRM,
# SIGPROF then SIGALRM), we maximize chances of hitting a bug.
self.setsig(signal.SIGPROF, first_handler)
self.setsig(signal.SIGUSR1, first_handler)
self.setsig(signal.SIGALRM, second_handler) # for ITIMER_REAL
expected_sigs = 0
deadline = time.monotonic() + support.SHORT_TIMEOUT
while expected_sigs < N:
os.kill(os.getpid(), signal.SIGPROF)
expected_sigs += 1
# Wait for handlers to run to avoid signal coalescing
while len(sigs) < expected_sigs and time.monotonic() < deadline:
time.sleep(1e-5)
os.kill(os.getpid(), signal.SIGUSR1)
expected_sigs += 1
while len(sigs) < expected_sigs and time.monotonic() < deadline:
time.sleep(1e-5)
# All ITIMER_REAL signals should have been delivered to the
# Python handler
self.assertEqual(len(sigs), N, "Some signals were lost")
@unittest.skipUnless(hasattr(signal, "setitimer"),
"test needs setitimer()")
def test_stress_delivery_simultaneous(self):
"""
This test uses simultaneous signal handlers.
"""
N = self.decide_itimer_count()
sigs = []
def handler(signum, frame):
sigs.append(signum)
# On Android, SIGUSR1 is unreliable when used in close proximity to
# another signal – see Android/testbed/app/src/main/python/main.py.
# So we use a different signal.
self.setsig(signal.SIGUSR2, handler)
self.setsig(signal.SIGALRM, handler) # for ITIMER_REAL
expected_sigs = 0
while expected_sigs < N:
# Hopefully the SIGALRM will be received somewhere during
# initial processing of SIGUSR2.
signal.setitimer(signal.ITIMER_REAL, 1e-6 + random.random() * 1e-5)
os.kill(os.getpid(), signal.SIGUSR2)
expected_sigs += 2
# Wait for handlers to run to avoid signal coalescing
for _ in support.sleeping_retry(support.SHORT_TIMEOUT):
if len(sigs) >= expected_sigs:
break
# All ITIMER_REAL signals should have been delivered to the
# Python handler
self.assertEqual(len(sigs), N, "Some signals were lost")
@support.requires_gil_enabled("gh-121065: test is flaky on free-threaded build")
@unittest.skipIf(is_apple, "crashes due to system bug (FB13453490)")
@unittest.skipUnless(hasattr(signal, "SIGUSR1"),
"test needs SIGUSR1")
@threading_helper.requires_working_threading()
def test_stress_modifying_handlers(self):
# bpo-43406: race condition between trip_signal() and signal.signal
signum = signal.SIGUSR1
num_sent_signals = 0
num_received_signals = 0
do_stop = False
def custom_handler(signum, frame):
nonlocal num_received_signals
num_received_signals += 1
def set_interrupts():
nonlocal num_sent_signals
while not do_stop:
signal.raise_signal(signum)
num_sent_signals += 1
def cycle_handlers():
while num_sent_signals < 100 or num_received_signals < 1:
for i in range(20000):
# Cycle between a Python-defined and a non-Python handler
for handler in [custom_handler, signal.SIG_IGN]:
signal.signal(signum, handler)
old_handler = signal.signal(signum, custom_handler)
self.addCleanup(signal.signal, signum, old_handler)
t = threading.Thread(target=set_interrupts)
try:
ignored = False
with support.catch_unraisable_exception() as cm:
t.start()
cycle_handlers()
do_stop = True
t.join()
if cm.unraisable is not None:
# An unraisable exception may be printed out when
# a signal is ignored due to the aforementioned
# race condition, check it.
self.assertIsInstance(cm.unraisable.exc_value, OSError)
self.assertIn(
f"Signal {signum:d} ignored due to race condition",
str(cm.unraisable.exc_value))
ignored = True
# bpo-43406: Even if it is unlikely, it's technically possible that
# all signals were ignored because of race conditions.
if not ignored:
# Sanity check that some signals were received, but not all
self.assertGreater(num_received_signals, 0)
self.assertLessEqual(num_received_signals, num_sent_signals)
finally:
do_stop = True
t.join()
class RaiseSignalTest(unittest.TestCase):
def test_sigint(self):
with self.assertRaises(KeyboardInterrupt):
signal.raise_signal(signal.SIGINT)
@unittest.skipIf(sys.platform != "win32", "Windows specific test")
def test_invalid_argument(self):
try:
SIGHUP = 1 # not supported on win32
signal.raise_signal(SIGHUP)
self.fail("OSError (Invalid argument) expected")
except OSError as e:
if e.errno == errno.EINVAL:
pass
else:
raise
def test_handler(self):
is_ok = False
def handler(a, b):
nonlocal is_ok
is_ok = True
old_signal = signal.signal(signal.SIGINT, handler)
self.addCleanup(signal.signal, signal.SIGINT, old_signal)
signal.raise_signal(signal.SIGINT)
self.assertTrue(is_ok)
def test__thread_interrupt_main(self):
# See https://github.com/python/cpython/issues/102397
code = """if 1:
import _thread
class Foo():
def __del__(self):
_thread.interrupt_main()
x = Foo()
"""
rc, out, err = assert_python_ok('-c', code)
self.assertIn(b'OSError: Signal 2 ignored due to race condition', err)
class PidfdSignalTest(unittest.TestCase):
@unittest.skipUnless(
hasattr(signal, "pidfd_send_signal"),
"pidfd support not built in",
)
def test_pidfd_send_signal(self):
with self.assertRaises(OSError) as cm:
signal.pidfd_send_signal(0, signal.SIGINT)
if cm.exception.errno == errno.ENOSYS:
self.skipTest("kernel does not support pidfds")
elif cm.exception.errno == errno.EPERM:
self.skipTest("Not enough privileges to use pidfs")
self.assertEqual(cm.exception.errno, errno.EBADF)
my_pidfd = os.open(f'/proc/{os.getpid()}', os.O_DIRECTORY)
self.addCleanup(os.close, my_pidfd)
with self.assertRaisesRegex(TypeError, "^siginfo must be None$"):
signal.pidfd_send_signal(my_pidfd, signal.SIGINT, object(), 0)
with self.assertRaises(KeyboardInterrupt):
signal.pidfd_send_signal(my_pidfd, signal.SIGINT)
def tearDownModule():
support.reap_children()
if __name__ == "__main__":
unittest.main()
Codebase Browser
cpython