import errno
import fcntl
import pty
import os
import sys
import signal
from test.test_support import verbose, TestSkipped, run_unittest
import unittest
TEST_STRING_1 = "I wish to buy a fish license.\n"
TEST_STRING_2 = "For my pet fish, Eric.\n"
if verbose:
def debug(msg):
print msg
else:
def debug(msg):
pass
def normalize_output(data):
# Some operating systems do conversions on newline. We could possibly
# fix that by doing the appropriate termios.tcsetattr()s. I couldn't
# figure out the right combo on Tru64 and I don't have an IRIX box.
# So just normalize the output and doc the problem O/Ses by allowing
# certain combinations for some platforms, but avoid allowing other
# differences (like extra whitespace, trailing garbage, etc.)
# This is about the best we can do without getting some feedback
# from someone more knowledgable.
# OSF/1 (Tru64) apparently turns \n into \r\r\n.
if data.endswith('\r\r\n'):
return data.replace('\r\r\n', '\n')
# IRIX apparently turns \n into \r\n.
if data.endswith('\r\n'):
return data.replace('\r\n', '\n')
return data
# Marginal testing of pty suite. Cannot do extensive 'do or fail' testing
# because pty code is not too portable.
# XXX(nnorwitz): these tests leak fds when there is an error.
class PtyTest(unittest.TestCase):
def setUp(self):
# isatty() and close() can hang on some platforms. Set an alarm
# before running the test to make sure we don't hang forever.
self.old_alarm = signal.signal(signal.SIGALRM, self.handle_sig)
signal.alarm(10)
def tearDown(self):
# remove alarm, restore old alarm handler
signal.alarm(0)
signal.signal(signal.SIGALRM, self.old_alarm)
def handle_sig(self, sig, frame):
self.fail("isatty hung")
def test_basic(self):
try:
debug("Calling master_open()")
master_fd, slave_name = pty.master_open()
debug("Got master_fd '%d', slave_name '%s'" %
(master_fd, slave_name))
debug("Calling slave_open(%r)" % (slave_name,))
slave_fd = pty.slave_open(slave_name)
debug("Got slave_fd '%d'" % slave_fd)
except OSError:
# " An optional feature could not be imported " ... ?
raise TestSkipped, "Pseudo-terminals (seemingly) not functional."
self.assertTrue(os.isatty(slave_fd), 'slave_fd is not a tty')
# Solaris requires reading the fd before anything is returned.
# My guess is that since we open and close the slave fd
# in master_open(), we need to read the EOF.
# Ensure the fd is non-blocking in case there's nothing to read.
orig_flags = fcntl.fcntl(master_fd, fcntl.F_GETFL)
fcntl.fcntl(master_fd, fcntl.F_SETFL, orig_flags | os.O_NONBLOCK)
try:
s1 = os.read(master_fd, 1024)
self.assertEquals('', s1)
except OSError, e:
if e.errno != errno.EAGAIN:
raise
# Restore the original flags.
fcntl.fcntl(master_fd, fcntl.F_SETFL, orig_flags)
debug("Writing to slave_fd")
os.write(slave_fd, TEST_STRING_1)
s1 = os.read(master_fd, 1024)
self.assertEquals('I wish to buy a fish license.\n',
normalize_output(s1))
debug("Writing chunked output")
os.write(slave_fd, TEST_STRING_2[:5])
os.write(slave_fd, TEST_STRING_2[5:])
s2 = os.read(master_fd, 1024)
self.assertEquals('For my pet fish, Eric.\n', normalize_output(s2))
os.close(slave_fd)
os.close(master_fd)
def test_fork(self):
debug("calling pty.fork()")
pid, master_fd = pty.fork()
if pid == pty.CHILD:
# stdout should be connected to a tty.
if not os.isatty(1):
debug("Child's fd 1 is not a tty?!")
os._exit(3)
# After pty.fork(), the child should already be a session leader.
# (on those systems that have that concept.)
debug("In child, calling os.setsid()")
try:
os.setsid()
except OSError:
# Good, we already were session leader
debug("Good: OSError was raised.")
pass
except AttributeError:
# Have pty, but not setsid()?
debug("No setsid() available?")
pass
except:
# We don't want this error to propagate, escaping the call to
# os._exit() and causing very peculiar behavior in the calling
# regrtest.py !
# Note: could add traceback printing here.
debug("An unexpected error was raised.")
os._exit(1)
else:
debug("os.setsid() succeeded! (bad!)")
os._exit(2)
os._exit(4)
else:
debug("Waiting for child (%d) to finish." % pid)
# In verbose mode, we have to consume the debug output from the
# child or the child will block, causing this test to hang in the
# parent's waitpid() call. The child blocks after a
# platform-dependent amount of data is written to its fd. On
# Linux 2.6, it's 4000 bytes and the child won't block, but on OS
# X even the small writes in the child above will block it. Also
# on Linux, the read() will throw an OSError (input/output error)
# when it tries to read past the end of the buffer but the child's
# already exited, so catch and discard those exceptions. It's not
# worth checking for EIO.
while True:
try:
data = os.read(master_fd, 80)
except OSError:
break
if not data:
break
sys.stdout.write(data.replace('\r\n', '\n'))
##line = os.read(master_fd, 80)
##lines = line.replace('\r\n', '\n').split('\n')
##if False and lines != ['In child, calling os.setsid()',
## 'Good: OSError was raised.', '']:
## raise TestFailed("Unexpected output from child: %r" % line)
(pid, status) = os.waitpid(pid, 0)
res = status >> 8
debug("Child (%d) exited with status %d (%d)." % (pid, res, status))
if res == 1:
self.fail("Child raised an unexpected exception in os.setsid()")
elif res == 2:
self.fail("pty.fork() failed to make child a session leader.")
elif res == 3:
self.fail("Child spawned by pty.fork() did not have a tty as stdout")
elif res != 4:
self.fail("pty.fork() failed for unknown reasons.")
##debug("Reading from master_fd now that the child has exited")
##try:
## s1 = os.read(master_fd, 1024)
##except os.error:
## pass
##else:
## raise TestFailed("Read from master_fd did not raise exception")
os.close(master_fd)
# pty.fork() passed.
def test_main(verbose=None):
run_unittest(PtyTest)
if __name__ == "__main__":
test_main()