Issue #11657: Fix sending file descriptors over 255 over a multiprocessing Pipe.

Also added some tests.
This commit is contained in:
Antoine Pitrou 2011-08-23 19:48:34 +02:00
commit 162fee109b
4 changed files with 86 additions and 4 deletions

View File

@ -577,7 +577,6 @@ def main(tests=None, testdir=None, verbose=0, quiet=False,
elif ok == FAILED:
bad.append(test)
elif ok == ENV_CHANGED:
bad.append(test)
environment_changed.append(test)
elif ok == SKIPPED:
skipped.append(test)

View File

@ -35,7 +35,7 @@ import multiprocessing.managers
import multiprocessing.heap
import multiprocessing.pool
from multiprocessing import util
from multiprocessing import util, reduction
try:
from multiprocessing.sharedctypes import Value, copy
@ -43,6 +43,11 @@ try:
except ImportError:
HAS_SHAREDCTYPES = False
try:
import msvcrt
except ImportError:
msvcrt = None
#
#
#
@ -89,6 +94,11 @@ else:
timeout = None
return handle in _select([handle], [], [], timeout)[0]
try:
MAXFD = os.sysconf("SC_OPEN_MAX")
except:
MAXFD = 256
#
# Some tests require ctypes
#
@ -1587,6 +1597,76 @@ class _TestConnection(BaseTestCase):
self.assertRaises(ValueError, a.send_bytes, msg, 4, -1)
@classmethod
def _is_fd_assigned(cls, fd):
try:
os.fstat(fd)
except OSError as e:
if e.errno == errno.EBADF:
return False
raise
else:
return True
@classmethod
def _writefd(cls, conn, data, create_dummy_fds=False):
if create_dummy_fds:
for i in range(0, 256):
if not cls._is_fd_assigned(i):
os.dup2(conn.fileno(), i)
fd = reduction.recv_handle(conn)
if msvcrt:
fd = msvcrt.open_osfhandle(fd, os.O_WRONLY)
os.write(fd, data)
os.close(fd)
def test_fd_transfer(self):
if self.TYPE != 'processes':
self.skipTest("only makes sense with processes")
conn, child_conn = self.Pipe(duplex=True)
p = self.Process(target=self._writefd, args=(child_conn, b"foo"))
p.start()
with open(test.support.TESTFN, "wb") as f:
fd = f.fileno()
if msvcrt:
fd = msvcrt.get_osfhandle(fd)
reduction.send_handle(conn, fd, p.pid)
p.join()
with open(test.support.TESTFN, "rb") as f:
self.assertEqual(f.read(), b"foo")
@unittest.skipIf(sys.platform == "win32",
"test semantics don't make sense on Windows")
@unittest.skipIf(MAXFD <= 256,
"largest assignable fd number is too small")
@unittest.skipUnless(hasattr(os, "dup2"),
"test needs os.dup2()")
def test_large_fd_transfer(self):
# With fd > 256 (issue #11657)
if self.TYPE != 'processes':
self.skipTest("only makes sense with processes")
conn, child_conn = self.Pipe(duplex=True)
p = self.Process(target=self._writefd, args=(child_conn, b"bar", True))
p.start()
with open(test.support.TESTFN, "wb") as f:
fd = f.fileno()
for newfd in range(256, MAXFD):
if not self._is_fd_assigned(newfd):
break
else:
self.fail("could not find an unassigned large file descriptor")
os.dup2(fd, newfd)
try:
reduction.send_handle(conn, newfd, p.pid)
finally:
os.close(newfd)
p.join()
with open(test.support.TESTFN, "rb") as f:
self.assertEqual(f.read(), b"bar")
class _TestListenerClient(BaseTestCase):
ALLOWED_TYPES = ('processes', 'threads')

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@ -268,6 +268,9 @@ Core and Builtins
Library
-------
- Issue #11657: Fix sending file descriptors over 255 over a multiprocessing
Pipe.
- Issue #12811: tabnanny.check() now promptly closes checked files. Patch by
Anthony Briggs.

View File

@ -111,7 +111,7 @@ multiprocessing_sendfd(PyObject *self, PyObject *args)
cmsg->cmsg_type = SCM_RIGHTS;
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
msg.msg_controllen = cmsg->cmsg_len;
*CMSG_DATA(cmsg) = fd;
* (int *) CMSG_DATA(cmsg) = fd;
Py_BEGIN_ALLOW_THREADS
res = sendmsg(conn, &msg, 0);
@ -154,7 +154,7 @@ multiprocessing_recvfd(PyObject *self, PyObject *args)
if (res < 0)
return PyErr_SetFromErrno(PyExc_OSError);
fd = *CMSG_DATA(cmsg);
fd = * (int *) CMSG_DATA(cmsg);
return Py_BuildValue("i", fd);
}