diff options
Diffstat (limited to 'Lib/test/eintrdata/eintr_tester.py')
| -rw-r--r-- | Lib/test/eintrdata/eintr_tester.py | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/Lib/test/eintrdata/eintr_tester.py b/Lib/test/eintrdata/eintr_tester.py new file mode 100644 index 0000000..f755880 --- /dev/null +++ b/Lib/test/eintrdata/eintr_tester.py @@ -0,0 +1,376 @@ +""" +This test suite exercises some system calls subject to interruption with EINTR, +to check that it is actually handled transparently. +It is intended to be run by the main test suite within a child process, to +ensure there is no background thread running (so that signals are delivered to +the correct thread). +Signals are generated in-process using setitimer(ITIMER_REAL), which allows +sub-second periodicity (contrarily to signal()). +""" + +import io +import os +import select +import signal +import socket +import time +import unittest + +from test import support + + +@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()") +class EINTRBaseTest(unittest.TestCase): + """ Base class for EINTR tests. """ + + # delay for initial signal delivery + signal_delay = 0.1 + # signal delivery periodicity + signal_period = 0.1 + # default sleep time for tests - should obviously have: + # sleep_time > signal_period + sleep_time = 0.2 + + @classmethod + def setUpClass(cls): + cls.orig_handler = signal.signal(signal.SIGALRM, lambda *args: None) + signal.setitimer(signal.ITIMER_REAL, cls.signal_delay, + cls.signal_period) + + @classmethod + def stop_alarm(cls): + signal.setitimer(signal.ITIMER_REAL, 0, 0) + + @classmethod + def tearDownClass(cls): + cls.stop_alarm() + signal.signal(signal.SIGALRM, cls.orig_handler) + + @classmethod + def _sleep(cls): + # default sleep time + time.sleep(cls.sleep_time) + + +@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()") +class OSEINTRTest(EINTRBaseTest): + """ EINTR tests for the os module. """ + + def _test_wait_multiple(self, wait_func): + num = 3 + for _ in range(num): + pid = os.fork() + if pid == 0: + self._sleep() + os._exit(0) + for _ in range(num): + wait_func() + + def test_wait(self): + self._test_wait_multiple(os.wait) + + @unittest.skipUnless(hasattr(os, 'wait3'), 'requires wait3()') + def test_wait3(self): + self._test_wait_multiple(lambda: os.wait3(0)) + + def _test_wait_single(self, wait_func): + pid = os.fork() + if pid == 0: + self._sleep() + os._exit(0) + else: + wait_func(pid) + + def test_waitpid(self): + self._test_wait_single(lambda pid: os.waitpid(pid, 0)) + + @unittest.skipUnless(hasattr(os, 'wait4'), 'requires wait4()') + def test_wait4(self): + self._test_wait_single(lambda pid: os.wait4(pid, 0)) + + def test_read(self): + rd, wr = os.pipe() + self.addCleanup(os.close, rd) + # wr closed explicitly by parent + + # the payload below are smaller than PIPE_BUF, hence the writes will be + # atomic + datas = [b"hello", b"world", b"spam"] + + pid = os.fork() + if pid == 0: + os.close(rd) + for data in datas: + # let the parent block on read() + self._sleep() + os.write(wr, data) + os._exit(0) + else: + self.addCleanup(os.waitpid, pid, 0) + os.close(wr) + for data in datas: + self.assertEqual(data, os.read(rd, len(data))) + + def test_write(self): + rd, wr = os.pipe() + self.addCleanup(os.close, wr) + # rd closed explicitly by parent + + # we must write enough data for the write() to block + data = b"xyz" * support.PIPE_MAX_SIZE + + pid = os.fork() + if pid == 0: + os.close(wr) + read_data = io.BytesIO() + # let the parent block on write() + self._sleep() + while len(read_data.getvalue()) < len(data): + chunk = os.read(rd, 2 * len(data)) + read_data.write(chunk) + self.assertEqual(read_data.getvalue(), data) + os._exit(0) + else: + os.close(rd) + written = 0 + while written < len(data): + written += os.write(wr, memoryview(data)[written:]) + self.assertEqual(0, os.waitpid(pid, 0)[1]) + + +@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()") +class SocketEINTRTest(EINTRBaseTest): + """ EINTR tests for the socket module. """ + + @unittest.skipUnless(hasattr(socket, 'socketpair'), 'needs socketpair()') + def _test_recv(self, recv_func): + rd, wr = socket.socketpair() + self.addCleanup(rd.close) + # wr closed explicitly by parent + + # single-byte payload guard us against partial recv + datas = [b"x", b"y", b"z"] + + pid = os.fork() + if pid == 0: + rd.close() + for data in datas: + # let the parent block on recv() + self._sleep() + wr.sendall(data) + os._exit(0) + else: + self.addCleanup(os.waitpid, pid, 0) + wr.close() + for data in datas: + self.assertEqual(data, recv_func(rd, len(data))) + + def test_recv(self): + self._test_recv(socket.socket.recv) + + @unittest.skipUnless(hasattr(socket.socket, 'recvmsg'), 'needs recvmsg()') + def test_recvmsg(self): + self._test_recv(lambda sock, data: sock.recvmsg(data)[0]) + + def _test_send(self, send_func): + rd, wr = socket.socketpair() + self.addCleanup(wr.close) + # rd closed explicitly by parent + + # we must send enough data for the send() to block + data = b"xyz" * (support.SOCK_MAX_SIZE // 3) + + pid = os.fork() + if pid == 0: + wr.close() + # let the parent block on send() + self._sleep() + received_data = bytearray(len(data)) + n = 0 + while n < len(data): + n += rd.recv_into(memoryview(received_data)[n:]) + self.assertEqual(received_data, data) + os._exit(0) + else: + rd.close() + written = 0 + while written < len(data): + sent = send_func(wr, memoryview(data)[written:]) + # sendall() returns None + written += len(data) if sent is None else sent + self.assertEqual(0, os.waitpid(pid, 0)[1]) + + def test_send(self): + self._test_send(socket.socket.send) + + def test_sendall(self): + self._test_send(socket.socket.sendall) + + @unittest.skipUnless(hasattr(socket.socket, 'sendmsg'), 'needs sendmsg()') + def test_sendmsg(self): + self._test_send(lambda sock, data: sock.sendmsg([data])) + + def test_accept(self): + sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) + self.addCleanup(sock.close) + + sock.bind((support.HOST, 0)) + _, port = sock.getsockname() + sock.listen() + + pid = os.fork() + if pid == 0: + # let parent block on accept() + self._sleep() + with socket.create_connection((support.HOST, port)): + self._sleep() + os._exit(0) + else: + self.addCleanup(os.waitpid, pid, 0) + client_sock, _ = sock.accept() + client_sock.close() + + @unittest.skipUnless(hasattr(os, 'mkfifo'), 'needs mkfifo()') + def _test_open(self, do_open_close_reader, do_open_close_writer): + # Use a fifo: until the child opens it for reading, the parent will + # block when trying to open it for writing. + support.unlink(support.TESTFN) + os.mkfifo(support.TESTFN) + self.addCleanup(support.unlink, support.TESTFN) + + pid = os.fork() + if pid == 0: + # let the parent block + self._sleep() + do_open_close_reader(support.TESTFN) + os._exit(0) + else: + self.addCleanup(os.waitpid, pid, 0) + do_open_close_writer(support.TESTFN) + + def test_open(self): + self._test_open(lambda path: open(path, 'r').close(), + lambda path: open(path, 'w').close()) + + def test_os_open(self): + self._test_open(lambda path: os.close(os.open(path, os.O_RDONLY)), + lambda path: os.close(os.open(path, os.O_WRONLY))) + + +@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()") +class TimeEINTRTest(EINTRBaseTest): + """ EINTR tests for the time module. """ + + def test_sleep(self): + t0 = time.monotonic() + time.sleep(self.sleep_time) + self.stop_alarm() + dt = time.monotonic() - t0 + self.assertGreaterEqual(dt, self.sleep_time) + + +@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()") +class SignalEINTRTest(EINTRBaseTest): + """ EINTR tests for the signal module. """ + + @unittest.skipUnless(hasattr(signal, 'sigtimedwait'), + 'need signal.sigtimedwait()') + def test_sigtimedwait(self): + t0 = time.monotonic() + signal.sigtimedwait([signal.SIGUSR1], self.sleep_time) + dt = time.monotonic() - t0 + self.assertGreaterEqual(dt, self.sleep_time) + + @unittest.skipUnless(hasattr(signal, 'sigwaitinfo'), + 'need signal.sigwaitinfo()') + def test_sigwaitinfo(self): + signum = signal.SIGUSR1 + pid = os.getpid() + + old_handler = signal.signal(signum, lambda *args: None) + self.addCleanup(signal.signal, signum, old_handler) + + t0 = time.monotonic() + child_pid = os.fork() + if child_pid == 0: + # child + try: + self._sleep() + os.kill(pid, signum) + finally: + os._exit(0) + else: + # parent + signal.sigwaitinfo([signum]) + dt = time.monotonic() - t0 + os.waitpid(child_pid, 0) + + self.assertGreaterEqual(dt, self.sleep_time) + + +@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()") +class SelectEINTRTest(EINTRBaseTest): + """ EINTR tests for the select module. """ + + def test_select(self): + t0 = time.monotonic() + select.select([], [], [], self.sleep_time) + dt = time.monotonic() - t0 + self.stop_alarm() + self.assertGreaterEqual(dt, self.sleep_time) + + @unittest.skipUnless(hasattr(select, 'poll'), 'need select.poll') + def test_poll(self): + poller = select.poll() + + t0 = time.monotonic() + poller.poll(self.sleep_time * 1e3) + dt = time.monotonic() - t0 + self.stop_alarm() + self.assertGreaterEqual(dt, self.sleep_time) + + @unittest.skipUnless(hasattr(select, 'epoll'), 'need select.epoll') + def test_epoll(self): + poller = select.epoll() + self.addCleanup(poller.close) + + t0 = time.monotonic() + poller.poll(self.sleep_time) + dt = time.monotonic() - t0 + self.stop_alarm() + self.assertGreaterEqual(dt, self.sleep_time) + + @unittest.skipUnless(hasattr(select, 'kqueue'), 'need select.kqueue') + def test_kqueue(self): + kqueue = select.kqueue() + self.addCleanup(kqueue.close) + + t0 = time.monotonic() + kqueue.control(None, 1, self.sleep_time) + dt = time.monotonic() - t0 + self.stop_alarm() + self.assertGreaterEqual(dt, self.sleep_time) + + @unittest.skipUnless(hasattr(select, 'devpoll'), 'need select.devpoll') + def test_devpoll(self): + poller = select.devpoll() + self.addCleanup(poller.close) + + t0 = time.monotonic() + poller.poll(self.sleep_time * 1e3) + dt = time.monotonic() - t0 + self.stop_alarm() + self.assertGreaterEqual(dt, self.sleep_time) + + +def test_main(): + support.run_unittest( + OSEINTRTest, + SocketEINTRTest, + TimeEINTRTest, + SignalEINTRTest, + SelectEINTRTest) + + +if __name__ == "__main__": + test_main() |