cpython/Lib/test/test_ioctl.py

85 lines
2.8 KiB
Python

import array
import unittest
from test.support import get_attribute
from test.support.import_helper import import_module
import os, struct
fcntl = import_module('fcntl')
termios = import_module('termios')
get_attribute(termios, 'TIOCGPGRP') #Can't run tests without this feature
try:
tty = open("/dev/tty", "rb")
except OSError:
raise unittest.SkipTest("Unable to open /dev/tty")
else:
with tty:
# Skip if another process is in foreground
r = fcntl.ioctl(tty, termios.TIOCGPGRP, " ")
rpgrp = struct.unpack("i", r)[0]
if rpgrp not in (os.getpgrp(), os.getsid(0)):
raise unittest.SkipTest("Neither the process group nor the session "
"are attached to /dev/tty")
del tty, r, rpgrp
try:
import pty
except ImportError:
pty = None
class IoctlTests(unittest.TestCase):
def test_ioctl(self):
# If this process has been put into the background, TIOCGPGRP returns
# the session ID instead of the process group id.
ids = (os.getpgrp(), os.getsid(0))
with open("/dev/tty", "rb") as tty:
r = fcntl.ioctl(tty, termios.TIOCGPGRP, " ")
rpgrp = struct.unpack("i", r)[0]
self.assertIn(rpgrp, ids)
def _check_ioctl_mutate_len(self, nbytes=None):
buf = array.array('i')
intsize = buf.itemsize
ids = (os.getpgrp(), os.getsid(0))
# A fill value unlikely to be in `ids`
fill = -12345
if nbytes is not None:
# Extend the buffer so that it is exactly `nbytes` bytes long
buf.extend([fill] * (nbytes // intsize))
self.assertEqual(len(buf) * intsize, nbytes) # sanity check
else:
buf.append(fill)
with open("/dev/tty", "rb") as tty:
r = fcntl.ioctl(tty, termios.TIOCGPGRP, buf, True)
rpgrp = buf[0]
self.assertEqual(r, 0)
self.assertIn(rpgrp, ids)
def test_ioctl_mutate(self):
self._check_ioctl_mutate_len()
def test_ioctl_mutate_1024(self):
# Issue #9758: a mutable buffer of exactly 1024 bytes wouldn't be
# copied back after the system call.
self._check_ioctl_mutate_len(1024)
def test_ioctl_mutate_2048(self):
# Test with a larger buffer, just for the record.
self._check_ioctl_mutate_len(2048)
@unittest.skipIf(pty is None, 'pty module required')
def test_ioctl_set_window_size(self):
mfd, sfd = pty.openpty()
try:
# (rows, columns, xpixel, ypixel)
our_winsz = struct.pack("HHHH", 20, 40, 0, 0)
result = fcntl.ioctl(mfd, termios.TIOCSWINSZ, our_winsz)
new_winsz = struct.unpack("HHHH", result)
self.assertEqual(new_winsz[:2], (20, 40))
finally:
os.close(mfd)
os.close(sfd)
if __name__ == "__main__":
unittest.main()