import unittest

from test.test_support import TestSkipped, run_unittest

import os, struct

try:

    import fcntl, termios

except ImportError:

    raise TestSkipped("No fcntl or termios module")

if not hasattr(termios,'TIOCGPGRP'):

    raise TestSkipped("termios module doesn't have TIOCGPGRP")

try:

    tty = open("/dev/tty", "r")

    tty.close()

except IOError:

    raise TestSkipped("Unable to open /dev/tty")

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))

        tty = open("/dev/tty", "r")

        r = fcntl.ioctl(tty, termios.TIOCGPGRP, "    ")

        rpgrp = struct.unpack("i", r)[0]

        self.assert_(rpgrp in ids, "%s not in %s" % (rpgrp, ids))

    def test_ioctl_mutate(self):

        import array

        buf = array.array('i', [0])

        ids = (os.getpgrp(), os.getsid(0))

        tty = open("/dev/tty", "r")

        r = fcntl.ioctl(tty, termios.TIOCGPGRP, buf, 1)

        rpgrp = buf[0]

        self.assertEquals(r, 0)

        self.assert_(rpgrp in ids, "%s not in %s" % (rpgrp, ids))

    def test_ioctl_signed_unsigned_code_param(self):

        if not pty:

            raise TestSkipped('pty module required')

        mfd, sfd = pty.openpty()

        try:

            if termios.TIOCSWINSZ < 0:

                set_winsz_opcode_maybe_neg = termios.TIOCSWINSZ

                set_winsz_opcode_pos = termios.TIOCSWINSZ & 0xffffffffL

            else:

                set_winsz_opcode_pos = termios.TIOCSWINSZ

                set_winsz_opcode_maybe_neg, = struct.unpack("i",

                        struct.pack("I", termios.TIOCSWINSZ))

            our_winsz = struct.pack("HHHH",80,25,0,0)

            # test both with a positive and potentially negative ioctl code

            new_winsz = fcntl.ioctl(mfd, set_winsz_opcode_pos, our_winsz)

            new_winsz = fcntl.ioctl(mfd, set_winsz_opcode_maybe_neg, our_winsz)

        finally:

            os.close(mfd)

            os.close(sfd)

def test_main():

    run_unittest(IoctlTests)

if __name__ == "__main__":

    test_main()