Python code coverage for Lib/test/eintrdata/eintr_tester.py

#	count	content
1	n/a	"""
2	n/a	This test suite exercises some system calls subject to interruption with EINTR,
3	n/a	to check that it is actually handled transparently.
4	n/a	It is intended to be run by the main test suite within a child process, to
5	n/a	ensure there is no background thread running (so that signals are delivered to
6	n/a	the correct thread).
7	n/a	Signals are generated in-process using setitimer(ITIMER_REAL), which allows
8	n/a	sub-second periodicity (contrarily to signal()).
9	n/a	"""
10	n/a
11	n/a	import contextlib
12	n/a	import faulthandler
13	n/a	import os
14	n/a	import select
15	n/a	import signal
16	n/a	import socket
17	n/a	import subprocess
18	n/a	import sys
19	n/a	import time
20	n/a	import unittest
21	n/a
22	n/a	from test import support
23	n/a	android_not_root = support.android_not_root
24	n/a
25	n/a	@contextlib.contextmanager
26	n/a	def kill_on_error(proc):
27	n/a	"""Context manager killing the subprocess if a Python exception is raised."""
28	n/a	with proc:
29	n/a	try:
30	n/a	yield proc
31	n/a	except:
32	n/a	proc.kill()
33	n/a	raise
34	n/a
35	n/a
36	n/a	@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()")
37	n/a	class EINTRBaseTest(unittest.TestCase):
38	n/a	""" Base class for EINTR tests. """
39	n/a
40	n/a	# delay for initial signal delivery
41	n/a	signal_delay = 0.1
42	n/a	# signal delivery periodicity
43	n/a	signal_period = 0.1
44	n/a	# default sleep time for tests - should obviously have:
45	n/a	# sleep_time > signal_period
46	n/a	sleep_time = 0.2
47	n/a
48	n/a	@classmethod
49	n/a	def setUpClass(cls):
50	n/a	cls.orig_handler = signal.signal(signal.SIGALRM, lambda *args: None)
51	n/a	signal.setitimer(signal.ITIMER_REAL, cls.signal_delay,
52	n/a	cls.signal_period)
53	n/a
54	n/a	# Issue #25277: Use faulthandler to try to debug a hang on FreeBSD
55	n/a	if hasattr(faulthandler, 'dump_traceback_later'):
56	n/a	faulthandler.dump_traceback_later(10 * 60, exit=True)
57	n/a
58	n/a	@classmethod
59	n/a	def stop_alarm(cls):
60	n/a	signal.setitimer(signal.ITIMER_REAL, 0, 0)
61	n/a
62	n/a	@classmethod
63	n/a	def tearDownClass(cls):
64	n/a	cls.stop_alarm()
65	n/a	signal.signal(signal.SIGALRM, cls.orig_handler)
66	n/a	if hasattr(faulthandler, 'cancel_dump_traceback_later'):
67	n/a	faulthandler.cancel_dump_traceback_later()
68	n/a
69	n/a	def subprocess(self, args, *kw):
70	n/a	cmd_args = (sys.executable, '-c') + args
71	n/a	return subprocess.Popen(cmd_args, **kw)
72	n/a
73	n/a
74	n/a	@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()")
75	n/a	class OSEINTRTest(EINTRBaseTest):
76	n/a	""" EINTR tests for the os module. """
77	n/a
78	n/a	def new_sleep_process(self):
79	n/a	code = 'import time; time.sleep(%r)' % self.sleep_time
80	n/a	return self.subprocess(code)
81	n/a
82	n/a	def _test_wait_multiple(self, wait_func):
83	n/a	num = 3
84	n/a	processes = [self.new_sleep_process() for _ in range(num)]
85	n/a	for _ in range(num):
86	n/a	wait_func()
87	n/a	# Call the Popen method to avoid a ResourceWarning
88	n/a	for proc in processes:
89	n/a	proc.wait()
90	n/a
91	n/a	def test_wait(self):
92	n/a	self._test_wait_multiple(os.wait)
93	n/a
94	n/a	@unittest.skipUnless(hasattr(os, 'wait3'), 'requires wait3()')
95	n/a	def test_wait3(self):
96	n/a	self._test_wait_multiple(lambda: os.wait3(0))
97	n/a
98	n/a	def _test_wait_single(self, wait_func):
99	n/a	proc = self.new_sleep_process()
100	n/a	wait_func(proc.pid)
101	n/a	# Call the Popen method to avoid a ResourceWarning
102	n/a	proc.wait()
103	n/a
104	n/a	def test_waitpid(self):
105	n/a	self._test_wait_single(lambda pid: os.waitpid(pid, 0))
106	n/a
107	n/a	@unittest.skipUnless(hasattr(os, 'wait4'), 'requires wait4()')
108	n/a	def test_wait4(self):
109	n/a	self._test_wait_single(lambda pid: os.wait4(pid, 0))
110	n/a
111	n/a	def test_read(self):
112	n/a	rd, wr = os.pipe()
113	n/a	self.addCleanup(os.close, rd)
114	n/a	# wr closed explicitly by parent
115	n/a
116	n/a	# the payload below are smaller than PIPE_BUF, hence the writes will be
117	n/a	# atomic
118	n/a	datas = [b"hello", b"world", b"spam"]
119	n/a
120	n/a	code = '\n'.join((
121	n/a	'import os, sys, time',
122	n/a	'',
123	n/a	'wr = int(sys.argv[1])',
124	n/a	'datas = %r' % datas,
125	n/a	'sleep_time = %r' % self.sleep_time,
126	n/a	'',
127	n/a	'for data in datas:',
128	n/a	' # let the parent block on read()',
129	n/a	' time.sleep(sleep_time)',
130	n/a	' os.write(wr, data)',
131	n/a	))
132	n/a
133	n/a	proc = self.subprocess(code, str(wr), pass_fds=[wr])
134	n/a	with kill_on_error(proc):
135	n/a	os.close(wr)
136	n/a	for data in datas:
137	n/a	self.assertEqual(data, os.read(rd, len(data)))
138	n/a	self.assertEqual(proc.wait(), 0)
139	n/a
140	n/a	def test_write(self):
141	n/a	rd, wr = os.pipe()
142	n/a	self.addCleanup(os.close, wr)
143	n/a	# rd closed explicitly by parent
144	n/a
145	n/a	# we must write enough data for the write() to block
146	n/a	data = b"x" * support.PIPE_MAX_SIZE
147	n/a
148	n/a	code = '\n'.join((
149	n/a	'import io, os, sys, time',
150	n/a	'',
151	n/a	'rd = int(sys.argv[1])',
152	n/a	'sleep_time = %r' % self.sleep_time,
153	n/a	'data = b"x" * %s' % support.PIPE_MAX_SIZE,
154	n/a	'data_len = len(data)',
155	n/a	'',
156	n/a	'# let the parent block on write()',
157	n/a	'time.sleep(sleep_time)',
158	n/a	'',
159	n/a	'read_data = io.BytesIO()',
160	n/a	'while len(read_data.getvalue()) < data_len:',
161	n/a	' chunk = os.read(rd, 2 * data_len)',
162	n/a	' read_data.write(chunk)',
163	n/a	'',
164	n/a	'value = read_data.getvalue()',
165	n/a	'if value != data:',
166	n/a	' raise Exception("read error: %s vs %s bytes"',
167	n/a	' % (len(value), data_len))',
168	n/a	))
169	n/a
170	n/a	proc = self.subprocess(code, str(rd), pass_fds=[rd])
171	n/a	with kill_on_error(proc):
172	n/a	os.close(rd)
173	n/a	written = 0
174	n/a	while written < len(data):
175	n/a	written += os.write(wr, memoryview(data)[written:])
176	n/a	self.assertEqual(proc.wait(), 0)
177	n/a
178	n/a
179	n/a	@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()")
180	n/a	class SocketEINTRTest(EINTRBaseTest):
181	n/a	""" EINTR tests for the socket module. """
182	n/a
183	n/a	@unittest.skipUnless(hasattr(socket, 'socketpair'), 'needs socketpair()')
184	n/a	def _test_recv(self, recv_func):
185	n/a	rd, wr = socket.socketpair()
186	n/a	self.addCleanup(rd.close)
187	n/a	# wr closed explicitly by parent
188	n/a
189	n/a	# single-byte payload guard us against partial recv
190	n/a	datas = [b"x", b"y", b"z"]
191	n/a
192	n/a	code = '\n'.join((
193	n/a	'import os, socket, sys, time',
194	n/a	'',
195	n/a	'fd = int(sys.argv[1])',
196	n/a	'family = %s' % int(wr.family),
197	n/a	'sock_type = %s' % int(wr.type),
198	n/a	'datas = %r' % datas,
199	n/a	'sleep_time = %r' % self.sleep_time,
200	n/a	'',
201	n/a	'wr = socket.fromfd(fd, family, sock_type)',
202	n/a	'os.close(fd)',
203	n/a	'',
204	n/a	'with wr:',
205	n/a	' for data in datas:',
206	n/a	' # let the parent block on recv()',
207	n/a	' time.sleep(sleep_time)',
208	n/a	' wr.sendall(data)',
209	n/a	))
210	n/a
211	n/a	fd = wr.fileno()
212	n/a	proc = self.subprocess(code, str(fd), pass_fds=[fd])
213	n/a	with kill_on_error(proc):
214	n/a	wr.close()
215	n/a	for data in datas:
216	n/a	self.assertEqual(data, recv_func(rd, len(data)))
217	n/a	self.assertEqual(proc.wait(), 0)
218	n/a
219	n/a	def test_recv(self):
220	n/a	self._test_recv(socket.socket.recv)
221	n/a
222	n/a	@unittest.skipUnless(hasattr(socket.socket, 'recvmsg'), 'needs recvmsg()')
223	n/a	def test_recvmsg(self):
224	n/a	self._test_recv(lambda sock, data: sock.recvmsg(data)[0])
225	n/a
226	n/a	def _test_send(self, send_func):
227	n/a	rd, wr = socket.socketpair()
228	n/a	self.addCleanup(wr.close)
229	n/a	# rd closed explicitly by parent
230	n/a
231	n/a	# we must send enough data for the send() to block
232	n/a	data = b"xyz" * (support.SOCK_MAX_SIZE // 3)
233	n/a
234	n/a	code = '\n'.join((
235	n/a	'import os, socket, sys, time',
236	n/a	'',
237	n/a	'fd = int(sys.argv[1])',
238	n/a	'family = %s' % int(rd.family),
239	n/a	'sock_type = %s' % int(rd.type),
240	n/a	'sleep_time = %r' % self.sleep_time,
241	n/a	'data = b"xyz" * %s' % (support.SOCK_MAX_SIZE // 3),
242	n/a	'data_len = len(data)',
243	n/a	'',
244	n/a	'rd = socket.fromfd(fd, family, sock_type)',
245	n/a	'os.close(fd)',
246	n/a	'',
247	n/a	'with rd:',
248	n/a	' # let the parent block on send()',
249	n/a	' time.sleep(sleep_time)',
250	n/a	'',
251	n/a	' received_data = bytearray(data_len)',
252	n/a	' n = 0',
253	n/a	' while n < data_len:',
254	n/a	' n += rd.recv_into(memoryview(received_data)[n:])',
255	n/a	'',
256	n/a	'if received_data != data:',
257	n/a	' raise Exception("recv error: %s vs %s bytes"',
258	n/a	' % (len(received_data), data_len))',
259	n/a	))
260	n/a
261	n/a	fd = rd.fileno()
262	n/a	proc = self.subprocess(code, str(fd), pass_fds=[fd])
263	n/a	with kill_on_error(proc):
264	n/a	rd.close()
265	n/a	written = 0
266	n/a	while written < len(data):
267	n/a	sent = send_func(wr, memoryview(data)[written:])
268	n/a	# sendall() returns None
269	n/a	written += len(data) if sent is None else sent
270	n/a	self.assertEqual(proc.wait(), 0)
271	n/a
272	n/a	def test_send(self):
273	n/a	self._test_send(socket.socket.send)
274	n/a
275	n/a	def test_sendall(self):
276	n/a	self._test_send(socket.socket.sendall)
277	n/a
278	n/a	@unittest.skipUnless(hasattr(socket.socket, 'sendmsg'), 'needs sendmsg()')
279	n/a	def test_sendmsg(self):
280	n/a	self._test_send(lambda sock, data: sock.sendmsg([data]))
281	n/a
282	n/a	def test_accept(self):
283	n/a	sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
284	n/a	self.addCleanup(sock.close)
285	n/a
286	n/a	sock.bind((support.HOST, 0))
287	n/a	port = sock.getsockname()[1]
288	n/a	sock.listen()
289	n/a
290	n/a	code = '\n'.join((
291	n/a	'import socket, time',
292	n/a	'',
293	n/a	'host = %r' % support.HOST,
294	n/a	'port = %s' % port,
295	n/a	'sleep_time = %r' % self.sleep_time,
296	n/a	'',
297	n/a	'# let parent block on accept()',
298	n/a	'time.sleep(sleep_time)',
299	n/a	'with socket.create_connection((host, port)):',
300	n/a	' time.sleep(sleep_time)',
301	n/a	))
302	n/a
303	n/a	proc = self.subprocess(code)
304	n/a	with kill_on_error(proc):
305	n/a	client_sock, _ = sock.accept()
306	n/a	client_sock.close()
307	n/a	self.assertEqual(proc.wait(), 0)
308	n/a
309	n/a	# Issue #25122: There is a race condition in the FreeBSD kernel on
310	n/a	# handling signals in the FIFO device. Skip the test until the bug is
311	n/a	# fixed in the kernel.
312	n/a	# https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=203162
313	n/a	@support.requires_freebsd_version(10, 3)
314	n/a	@unittest.skipUnless(hasattr(os, 'mkfifo'), 'needs mkfifo()')
315	n/a	@unittest.skipIf(android_not_root, "mkfifo not allowed, non root user")
316	n/a	def _test_open(self, do_open_close_reader, do_open_close_writer):
317	n/a	filename = support.TESTFN
318	n/a
319	n/a	# Use a fifo: until the child opens it for reading, the parent will
320	n/a	# block when trying to open it for writing.
321	n/a	support.unlink(filename)
322	n/a	os.mkfifo(filename)
323	n/a	self.addCleanup(support.unlink, filename)
324	n/a
325	n/a	code = '\n'.join((
326	n/a	'import os, time',
327	n/a	'',
328	n/a	'path = %a' % filename,
329	n/a	'sleep_time = %r' % self.sleep_time,
330	n/a	'',
331	n/a	'# let the parent block',
332	n/a	'time.sleep(sleep_time)',
333	n/a	'',
334	n/a	do_open_close_reader,
335	n/a	))
336	n/a
337	n/a	proc = self.subprocess(code)
338	n/a	with kill_on_error(proc):
339	n/a	do_open_close_writer(filename)
340	n/a	self.assertEqual(proc.wait(), 0)
341	n/a
342	n/a	def python_open(self, path):
343	n/a	fp = open(path, 'w')
344	n/a	fp.close()
345	n/a
346	n/a	def test_open(self):
347	n/a	self._test_open("fp = open(path, 'r')\nfp.close()",
348	n/a	self.python_open)
349	n/a
350	n/a	@unittest.skipIf(sys.platform == 'darwin', "hangs under OS X; see issue #25234")
351	n/a	def os_open(self, path):
352	n/a	fd = os.open(path, os.O_WRONLY)
353	n/a	os.close(fd)
354	n/a
355	n/a	@unittest.skipIf(sys.platform == "darwin", "hangs under OS X; see issue #25234")
356	n/a	def test_os_open(self):
357	n/a	self._test_open("fd = os.open(path, os.O_RDONLY)\nos.close(fd)",
358	n/a	self.os_open)
359	n/a
360	n/a
361	n/a	@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()")
362	n/a	class TimeEINTRTest(EINTRBaseTest):
363	n/a	""" EINTR tests for the time module. """
364	n/a
365	n/a	def test_sleep(self):
366	n/a	t0 = time.monotonic()
367	n/a	time.sleep(self.sleep_time)
368	n/a	self.stop_alarm()
369	n/a	dt = time.monotonic() - t0
370	n/a	self.assertGreaterEqual(dt, self.sleep_time)
371	n/a
372	n/a
373	n/a	@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()")
374	n/a	class SignalEINTRTest(EINTRBaseTest):
375	n/a	""" EINTR tests for the signal module. """
376	n/a
377	n/a	@unittest.skipUnless(hasattr(signal, 'sigtimedwait'),
378	n/a	'need signal.sigtimedwait()')
379	n/a	def test_sigtimedwait(self):
380	n/a	t0 = time.monotonic()
381	n/a	signal.sigtimedwait([signal.SIGUSR1], self.sleep_time)
382	n/a	dt = time.monotonic() - t0
383	n/a	self.assertGreaterEqual(dt, self.sleep_time)
384	n/a
385	n/a	@unittest.skipUnless(hasattr(signal, 'sigwaitinfo'),
386	n/a	'need signal.sigwaitinfo()')
387	n/a	def test_sigwaitinfo(self):
388	n/a	# Issue #25277, #25868: give a few milliseconds to the parent process
389	n/a	# between os.write() and signal.sigwaitinfo() to works around a race
390	n/a	# condition
391	n/a	self.sleep_time = 0.100
392	n/a
393	n/a	signum = signal.SIGUSR1
394	n/a	pid = os.getpid()
395	n/a
396	n/a	old_handler = signal.signal(signum, lambda *args: None)
397	n/a	self.addCleanup(signal.signal, signum, old_handler)
398	n/a
399	n/a	rpipe, wpipe = os.pipe()
400	n/a
401	n/a	code = '\n'.join((
402	n/a	'import os, time',
403	n/a	'pid = %s' % os.getpid(),
404	n/a	'signum = %s' % int(signum),
405	n/a	'sleep_time = %r' % self.sleep_time,
406	n/a	'rpipe = %r' % rpipe,
407	n/a	'os.read(rpipe, 1)',
408	n/a	'os.close(rpipe)',
409	n/a	'time.sleep(sleep_time)',
410	n/a	'os.kill(pid, signum)',
411	n/a	))
412	n/a
413	n/a	t0 = time.monotonic()
414	n/a	proc = self.subprocess(code, pass_fds=(rpipe,))
415	n/a	os.close(rpipe)
416	n/a	with kill_on_error(proc):
417	n/a	# sync child-parent
418	n/a	os.write(wpipe, b'x')
419	n/a	os.close(wpipe)
420	n/a
421	n/a	# parent
422	n/a	signal.sigwaitinfo([signum])
423	n/a	dt = time.monotonic() - t0
424	n/a	self.assertEqual(proc.wait(), 0)
425	n/a
426	n/a	self.assertGreaterEqual(dt, self.sleep_time)
427	n/a
428	n/a
429	n/a	@unittest.skipUnless(hasattr(signal, "setitimer"), "requires setitimer()")
430	n/a	class SelectEINTRTest(EINTRBaseTest):
431	n/a	""" EINTR tests for the select module. """
432	n/a
433	n/a	def test_select(self):
434	n/a	t0 = time.monotonic()
435	n/a	select.select([], [], [], self.sleep_time)
436	n/a	dt = time.monotonic() - t0
437	n/a	self.stop_alarm()
438	n/a	self.assertGreaterEqual(dt, self.sleep_time)
439	n/a
440	n/a	@unittest.skipUnless(hasattr(select, 'poll'), 'need select.poll')
441	n/a	def test_poll(self):
442	n/a	poller = select.poll()
443	n/a
444	n/a	t0 = time.monotonic()
445	n/a	poller.poll(self.sleep_time * 1e3)
446	n/a	dt = time.monotonic() - t0
447	n/a	self.stop_alarm()
448	n/a	self.assertGreaterEqual(dt, self.sleep_time)
449	n/a
450	n/a	@unittest.skipUnless(hasattr(select, 'epoll'), 'need select.epoll')
451	n/a	def test_epoll(self):
452	n/a	poller = select.epoll()
453	n/a	self.addCleanup(poller.close)
454	n/a
455	n/a	t0 = time.monotonic()
456	n/a	poller.poll(self.sleep_time)
457	n/a	dt = time.monotonic() - t0
458	n/a	self.stop_alarm()
459	n/a	self.assertGreaterEqual(dt, self.sleep_time)
460	n/a
461	n/a	@unittest.skipUnless(hasattr(select, 'kqueue'), 'need select.kqueue')
462	n/a	def test_kqueue(self):
463	n/a	kqueue = select.kqueue()
464	n/a	self.addCleanup(kqueue.close)
465	n/a
466	n/a	t0 = time.monotonic()
467	n/a	kqueue.control(None, 1, self.sleep_time)
468	n/a	dt = time.monotonic() - t0
469	n/a	self.stop_alarm()
470	n/a	self.assertGreaterEqual(dt, self.sleep_time)
471	n/a
472	n/a	@unittest.skipUnless(hasattr(select, 'devpoll'), 'need select.devpoll')
473	n/a	def test_devpoll(self):
474	n/a	poller = select.devpoll()
475	n/a	self.addCleanup(poller.close)
476	n/a
477	n/a	t0 = time.monotonic()
478	n/a	poller.poll(self.sleep_time * 1e3)
479	n/a	dt = time.monotonic() - t0
480	n/a	self.stop_alarm()
481	n/a	self.assertGreaterEqual(dt, self.sleep_time)
482	n/a
483	n/a
484	n/a	def test_main():
485	n/a	support.run_unittest(
486	n/a	OSEINTRTest,
487	n/a	SocketEINTRTest,
488	n/a	TimeEINTRTest,
489	n/a	SignalEINTRTest,
490	n/a	SelectEINTRTest)
491	n/a
492	n/a
493	n/a	if __name__ == "__main__":
494	n/a	test_main()