1 from test.support import verbose, reap_children
2 from test.support.import_helper import import_module
3
4 # Skip these tests if termios or fcntl are not available
5 import_module('termios')
6 # fcntl is a proxy for not being one of the wasm32 platforms even though we
7 # don't use this module... a proper check for what crashes those is needed.
8 import_module("fcntl")
9
10 import errno
11 import os
12 import pty
13 import tty
14 import sys
15 import select
16 import signal
17 import socket
18 import io # readline
19 import unittest
20 import warnings
21
22 TEST_STRING_1 = b"I wish to buy a fish license.\n"
23 TEST_STRING_2 = b"For my pet fish, Eric.\n"
24
25 _HAVE_WINSZ = hasattr(tty, "TIOCGWINSZ") and hasattr(tty, "TIOCSWINSZ")
26
27 if verbose:
28 def debug(msg):
29 print(msg)
30 else:
31 def debug(msg):
32 pass
33
34
35 # Note that os.read() is nondeterministic so we need to be very careful
36 # to make the test suite deterministic. A normal call to os.read() may
37 # give us less than expected.
38 #
39 # Beware, on my Linux system, if I put 'foo\n' into a terminal fd, I get
40 # back 'foo\r\n' at the other end. The behavior depends on the termios
41 # setting. The newline translation may be OS-specific. To make the
42 # test suite deterministic and OS-independent, the functions _readline
43 # and normalize_output can be used.
44
45 def normalize_output(data):
46 # Some operating systems do conversions on newline. We could possibly fix
47 # that by doing the appropriate termios.tcsetattr()s. I couldn't figure out
48 # the right combo on Tru64. So, just normalize the output and doc the
49 # problem O/Ses by allowing certain combinations for some platforms, but
50 # avoid allowing other differences (like extra whitespace, trailing garbage,
51 # etc.)
52
53 # This is about the best we can do without getting some feedback
54 # from someone more knowledgable.
55
56 # OSF/1 (Tru64) apparently turns \n into \r\r\n.
57 if data.endswith(b'\r\r\n'):
58 return data.replace(b'\r\r\n', b'\n')
59
60 if data.endswith(b'\r\n'):
61 return data.replace(b'\r\n', b'\n')
62
63 return data
64
65 def _readline(fd):
66 """Read one line. May block forever if no newline is read."""
67 reader = io.FileIO(fd, mode='rb', closefd=False)
68 return reader.readline()
69
70 def expectedFailureIfStdinIsTTY(fun):
71 # avoid isatty()
72 try:
73 tty.tcgetattr(pty.STDIN_FILENO)
74 return unittest.expectedFailure(fun)
75 except tty.error:
76 pass
77 return fun
78
79
80 def write_all(fd, data):
81 written = os.write(fd, data)
82 if written != len(data):
83 # gh-73256, gh-110673: It should never happen, but check just in case
84 raise Exception(f"short write: os.write({fd}, {len(data)} bytes) "
85 f"wrote {written} bytes")
86
87
88 # Marginal testing of pty suite. Cannot do extensive 'do or fail' testing
89 # because pty code is not too portable.
90 class ESC[4;38;5;81mPtyTest(ESC[4;38;5;149munittestESC[4;38;5;149m.ESC[4;38;5;149mTestCase):
91 def setUp(self):
92 old_sighup = signal.signal(signal.SIGHUP, self.handle_sighup)
93 self.addCleanup(signal.signal, signal.SIGHUP, old_sighup)
94
95 # Save original stdin window size.
96 self.stdin_dim = None
97 if _HAVE_WINSZ:
98 try:
99 self.stdin_dim = tty.tcgetwinsize(pty.STDIN_FILENO)
100 self.addCleanup(tty.tcsetwinsize, pty.STDIN_FILENO,
101 self.stdin_dim)
102 except tty.error:
103 pass
104
105 @staticmethod
106 def handle_sighup(signum, frame):
107 pass
108
109 @expectedFailureIfStdinIsTTY
110 def test_openpty(self):
111 try:
112 mode = tty.tcgetattr(pty.STDIN_FILENO)
113 except tty.error:
114 # Not a tty or bad/closed fd.
115 debug("tty.tcgetattr(pty.STDIN_FILENO) failed")
116 mode = None
117
118 new_dim = None
119 if self.stdin_dim:
120 try:
121 # Modify pty.STDIN_FILENO window size; we need to
122 # check if pty.openpty() is able to set pty slave
123 # window size accordingly.
124 debug("Setting pty.STDIN_FILENO window size.")
125 debug(f"original size: (row, col) = {self.stdin_dim}")
126 target_dim = (self.stdin_dim[0] + 1, self.stdin_dim[1] + 1)
127 debug(f"target size: (row, col) = {target_dim}")
128 tty.tcsetwinsize(pty.STDIN_FILENO, target_dim)
129
130 # Were we able to set the window size
131 # of pty.STDIN_FILENO successfully?
132 new_dim = tty.tcgetwinsize(pty.STDIN_FILENO)
133 self.assertEqual(new_dim, target_dim,
134 "pty.STDIN_FILENO window size unchanged")
135 except OSError:
136 warnings.warn("Failed to set pty.STDIN_FILENO window size.")
137 pass
138
139 try:
140 debug("Calling pty.openpty()")
141 try:
142 master_fd, slave_fd, slave_name = pty.openpty(mode, new_dim,
143 True)
144 except TypeError:
145 master_fd, slave_fd = pty.openpty()
146 slave_name = None
147 debug(f"Got {master_fd=}, {slave_fd=}, {slave_name=}")
148 except OSError:
149 # " An optional feature could not be imported " ... ?
150 raise unittest.SkipTest("Pseudo-terminals (seemingly) not functional.")
151
152 # closing master_fd can raise a SIGHUP if the process is
153 # the session leader: we installed a SIGHUP signal handler
154 # to ignore this signal.
155 self.addCleanup(os.close, master_fd)
156 self.addCleanup(os.close, slave_fd)
157
158 self.assertTrue(os.isatty(slave_fd), "slave_fd is not a tty")
159
160 if mode:
161 self.assertEqual(tty.tcgetattr(slave_fd), mode,
162 "openpty() failed to set slave termios")
163 if new_dim:
164 self.assertEqual(tty.tcgetwinsize(slave_fd), new_dim,
165 "openpty() failed to set slave window size")
166
167 # Ensure the fd is non-blocking in case there's nothing to read.
168 blocking = os.get_blocking(master_fd)
169 try:
170 os.set_blocking(master_fd, False)
171 try:
172 s1 = os.read(master_fd, 1024)
173 self.assertEqual(b'', s1)
174 except OSError as e:
175 if e.errno != errno.EAGAIN:
176 raise
177 finally:
178 # Restore the original flags.
179 os.set_blocking(master_fd, blocking)
180
181 debug("Writing to slave_fd")
182 write_all(slave_fd, TEST_STRING_1)
183 s1 = _readline(master_fd)
184 self.assertEqual(b'I wish to buy a fish license.\n',
185 normalize_output(s1))
186
187 debug("Writing chunked output")
188 write_all(slave_fd, TEST_STRING_2[:5])
189 write_all(slave_fd, TEST_STRING_2[5:])
190 s2 = _readline(master_fd)
191 self.assertEqual(b'For my pet fish, Eric.\n', normalize_output(s2))
192
193 def test_fork(self):
194 debug("calling pty.fork()")
195 pid, master_fd = pty.fork()
196 self.addCleanup(os.close, master_fd)
197 if pid == pty.CHILD:
198 # stdout should be connected to a tty.
199 if not os.isatty(1):
200 debug("Child's fd 1 is not a tty?!")
201 os._exit(3)
202
203 # After pty.fork(), the child should already be a session leader.
204 # (on those systems that have that concept.)
205 debug("In child, calling os.setsid()")
206 try:
207 os.setsid()
208 except OSError:
209 # Good, we already were session leader
210 debug("Good: OSError was raised.")
211 pass
212 except AttributeError:
213 # Have pty, but not setsid()?
214 debug("No setsid() available?")
215 pass
216 except:
217 # We don't want this error to propagate, escaping the call to
218 # os._exit() and causing very peculiar behavior in the calling
219 # regrtest.py !
220 # Note: could add traceback printing here.
221 debug("An unexpected error was raised.")
222 os._exit(1)
223 else:
224 debug("os.setsid() succeeded! (bad!)")
225 os._exit(2)
226 os._exit(4)
227 else:
228 debug("Waiting for child (%d) to finish." % pid)
229 # In verbose mode, we have to consume the debug output from the
230 # child or the child will block, causing this test to hang in the
231 # parent's waitpid() call. The child blocks after a
232 # platform-dependent amount of data is written to its fd. On
233 # Linux 2.6, it's 4000 bytes and the child won't block, but on OS
234 # X even the small writes in the child above will block it. Also
235 # on Linux, the read() will raise an OSError (input/output error)
236 # when it tries to read past the end of the buffer but the child's
237 # already exited, so catch and discard those exceptions. It's not
238 # worth checking for EIO.
239 while True:
240 try:
241 data = os.read(master_fd, 80)
242 except OSError:
243 break
244 if not data:
245 break
246 sys.stdout.write(str(data.replace(b'\r\n', b'\n'),
247 encoding='ascii'))
248
249 ##line = os.read(master_fd, 80)
250 ##lines = line.replace('\r\n', '\n').split('\n')
251 ##if False and lines != ['In child, calling os.setsid()',
252 ## 'Good: OSError was raised.', '']:
253 ## raise TestFailed("Unexpected output from child: %r" % line)
254
255 (pid, status) = os.waitpid(pid, 0)
256 res = os.waitstatus_to_exitcode(status)
257 debug("Child (%d) exited with code %d (status %d)." % (pid, res, status))
258 if res == 1:
259 self.fail("Child raised an unexpected exception in os.setsid()")
260 elif res == 2:
261 self.fail("pty.fork() failed to make child a session leader.")
262 elif res == 3:
263 self.fail("Child spawned by pty.fork() did not have a tty as stdout")
264 elif res != 4:
265 self.fail("pty.fork() failed for unknown reasons.")
266
267 ##debug("Reading from master_fd now that the child has exited")
268 ##try:
269 ## s1 = os.read(master_fd, 1024)
270 ##except OSError:
271 ## pass
272 ##else:
273 ## raise TestFailed("Read from master_fd did not raise exception")
274
275 def test_master_read(self):
276 # XXX(nnorwitz): this test leaks fds when there is an error.
277 debug("Calling pty.openpty()")
278 master_fd, slave_fd = pty.openpty()
279 debug(f"Got master_fd '{master_fd}', slave_fd '{slave_fd}'")
280
281 self.addCleanup(os.close, master_fd)
282
283 debug("Closing slave_fd")
284 os.close(slave_fd)
285
286 debug("Reading from master_fd")
287 try:
288 data = os.read(master_fd, 1)
289 except OSError: # Linux
290 data = b""
291
292 self.assertEqual(data, b"")
293
294 def test_spawn_doesnt_hang(self):
295 pty.spawn([sys.executable, '-c', 'print("hi there")'])
296
297 class ESC[4;38;5;81mSmallPtyTests(ESC[4;38;5;149munittestESC[4;38;5;149m.ESC[4;38;5;149mTestCase):
298 """These tests don't spawn children or hang."""
299
300 def setUp(self):
301 self.orig_stdin_fileno = pty.STDIN_FILENO
302 self.orig_stdout_fileno = pty.STDOUT_FILENO
303 self.orig_pty_close = pty.close
304 self.orig_pty__copy = pty._copy
305 self.orig_pty_fork = pty.fork
306 self.orig_pty_select = pty.select
307 self.orig_pty_setraw = pty.setraw
308 self.orig_pty_tcgetattr = pty.tcgetattr
309 self.orig_pty_tcsetattr = pty.tcsetattr
310 self.orig_pty_waitpid = pty.waitpid
311 self.fds = [] # A list of file descriptors to close.
312 self.files = []
313 self.select_input = []
314 self.select_output = []
315 self.tcsetattr_mode_setting = None
316
317 def tearDown(self):
318 pty.STDIN_FILENO = self.orig_stdin_fileno
319 pty.STDOUT_FILENO = self.orig_stdout_fileno
320 pty.close = self.orig_pty_close
321 pty._copy = self.orig_pty__copy
322 pty.fork = self.orig_pty_fork
323 pty.select = self.orig_pty_select
324 pty.setraw = self.orig_pty_setraw
325 pty.tcgetattr = self.orig_pty_tcgetattr
326 pty.tcsetattr = self.orig_pty_tcsetattr
327 pty.waitpid = self.orig_pty_waitpid
328 for file in self.files:
329 try:
330 file.close()
331 except OSError:
332 pass
333 for fd in self.fds:
334 try:
335 os.close(fd)
336 except OSError:
337 pass
338
339 def _pipe(self):
340 pipe_fds = os.pipe()
341 self.fds.extend(pipe_fds)
342 return pipe_fds
343
344 def _socketpair(self):
345 socketpair = socket.socketpair()
346 self.files.extend(socketpair)
347 return socketpair
348
349 def _mock_select(self, rfds, wfds, xfds):
350 # This will raise IndexError when no more expected calls exist.
351 self.assertEqual((rfds, wfds, xfds), self.select_input.pop(0))
352 return self.select_output.pop(0)
353
354 def _make_mock_fork(self, pid):
355 def mock_fork():
356 return (pid, 12)
357 return mock_fork
358
359 def _mock_tcsetattr(self, fileno, opt, mode):
360 self.tcsetattr_mode_setting = mode
361
362 def test__copy_to_each(self):
363 """Test the normal data case on both master_fd and stdin."""
364 read_from_stdout_fd, mock_stdout_fd = self._pipe()
365 pty.STDOUT_FILENO = mock_stdout_fd
366 mock_stdin_fd, write_to_stdin_fd = self._pipe()
367 pty.STDIN_FILENO = mock_stdin_fd
368 socketpair = self._socketpair()
369 masters = [s.fileno() for s in socketpair]
370
371 # Feed data. Smaller than PIPEBUF. These writes will not block.
372 write_all(masters[1], b'from master')
373 write_all(write_to_stdin_fd, b'from stdin')
374
375 # Expect three select calls, the last one will cause IndexError
376 pty.select = self._mock_select
377 self.select_input.append(([mock_stdin_fd, masters[0]], [], []))
378 self.select_output.append(([mock_stdin_fd, masters[0]], [], []))
379 self.select_input.append(([mock_stdin_fd, masters[0]], [mock_stdout_fd, masters[0]], []))
380 self.select_output.append(([], [mock_stdout_fd, masters[0]], []))
381 self.select_input.append(([mock_stdin_fd, masters[0]], [], []))
382
383 with self.assertRaises(IndexError):
384 pty._copy(masters[0])
385
386 # Test that the right data went to the right places.
387 rfds = select.select([read_from_stdout_fd, masters[1]], [], [], 0)[0]
388 self.assertEqual([read_from_stdout_fd, masters[1]], rfds)
389 self.assertEqual(os.read(read_from_stdout_fd, 20), b'from master')
390 self.assertEqual(os.read(masters[1], 20), b'from stdin')
391
392 def test__restore_tty_mode_normal_return(self):
393 """Test that spawn resets the tty mode no when _copy returns normally."""
394
395 # PID 1 is returned from mocked fork to run the parent branch
396 # of code
397 pty.fork = self._make_mock_fork(1)
398
399 status_sentinel = object()
400 pty.waitpid = lambda _1, _2: [None, status_sentinel]
401 pty.close = lambda _: None
402
403 pty._copy = lambda _1, _2, _3: None
404
405 mode_sentinel = object()
406 pty.tcgetattr = lambda fd: mode_sentinel
407 pty.tcsetattr = self._mock_tcsetattr
408 pty.setraw = lambda _: None
409
410 self.assertEqual(pty.spawn([]), status_sentinel, "pty.waitpid process status not returned by pty.spawn")
411 self.assertEqual(self.tcsetattr_mode_setting, mode_sentinel, "pty.tcsetattr not called with original mode value")
412
413
414 def tearDownModule():
415 reap_children()
416
417
418 if __name__ == "__main__":
419 unittest.main()