(backport of r61652 and r61665 from trunk)

Issue #1471: Arguments to fcntl.ioctl are no longer broken on 64-bit OpenBSD
and similar platforms due to sign extension.
This commit is contained in:
Gregory P. Smith 2008-08-04 00:45:34 +00:00
parent 76f5d1419f
commit 03e5182dca
3 changed files with 46 additions and 5 deletions

View File

@ -14,6 +14,11 @@ try:
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
@ -34,6 +39,30 @@ class IoctlTests(unittest.TestCase):
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))
# We're just testing that these calls do not raise exceptions.
saved_winsz = fcntl.ioctl(mfd, termios.TIOCGWINSZ, "\0"*8)
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)
fcntl.ioctl(mfd, set_winsz_opcode_maybe_neg, saved_winsz)
finally:
os.close(mfd)
os.close(sfd)
def test_main():
run_unittest(IoctlTests)

View File

@ -143,6 +143,9 @@ Extension Modules
- Issue #3120: On 64-bit Windows the subprocess module was truncating handles.
- Issue #1471: Arguments to fcntl.ioctl are no longer broken on 64-bit OpenBSD
and similar platforms due to sign extension.
Tests
-----

View File

@ -97,11 +97,20 @@ fcntl_ioctl(PyObject *self, PyObject *args)
{
#define IOCTL_BUFSZ 1024
int fd;
/* In PyArg_ParseTuple below, use the unsigned int 'I' format for
the signed int 'code' variable, because Python turns 0x8000000
into a large positive number (PyLong, or PyInt on 64-bit
platforms,) whereas C expects it to be a negative int */
int code;
/* In PyArg_ParseTuple below, we use the unsigned non-checked 'I'
format for the 'code' parameter because Python turns 0x8000000
into either a large positive number (PyLong or PyInt on 64-bit
platforms) or a negative number on others (32-bit PyInt)
whereas the system expects it to be a 32bit bit field value
regardless of it being passed as an int or unsigned long on
various platforms. See the termios.TIOCSWINSZ constant across
platforms for an example of thise.
If any of the 64bit platforms ever decide to use more than 32bits
in their unsigned long ioctl codes this will break and need
special casing based on the platform being built on.
*/
unsigned int code;
int arg;
int ret;
char *str;