def test_expectedFDs(self):
"""
L{_listOpenFDs} lists expected file descriptors.
"""
openfds = process._listOpenFDs()
for f in sys.stdin, sys.stdout, sys.stderr:
self.assertIn(f.fileno(), openfds)
# See http://twistedmatrix.com/trac/ticket/4522#comment:17
f = file(os.devnull)
fd = os.dup(f.fileno())
try:
f.close()
self.assertIn(fd, process._listOpenFDs())
finally:
os.close(fd)
self.assertNotIn(fd, process._listOpenFDs())
def test_expectedFDs(self):
"""
L{_listOpenFDs} lists expected file descriptors.
"""
# This is a tricky test. A priori, there is no way to know what file
# descriptors are open now, so there is no way to know what _listOpenFDs
# should return. Work around this by creating some new file descriptors
# which we can know the state of and then just making assertions about
# their presence or absence in the result.
# Expect a file we just opened to be listed.
f = open(os.devnull)
openfds = process._listOpenFDs()
self.assertIn(f.fileno(), openfds)
# Expect a file we just closed not to be listed - with a caveat. The
# implementation may need to open a file to discover the result. That
# open file descriptor will be allocated the same number as the one we
# just closed. So, instead, create a hole in the file descriptor space
# to catch that internal descriptor and make the assertion about a
# different closed file descriptor.
# This gets allocated a file descriptor larger than f's, since nothing
# has been closed since we opened f.
fd = os.dup(f.fileno())
# But sanity check that; if it fails the test is invalid.
self.assertTrue(
fd > f.fileno(),
"Expected duplicate file descriptor to be greater than original",
)
try:
# Get rid of the original, creating the hole. The copy should still
# be open, of course.
f.close()
self.assertIn(fd, process._listOpenFDs())
finally:
# Get rid of the copy now
os.close(fd)
# And it should not appear in the result.
self.assertNotIn(fd, process._listOpenFDs())
def test_expectedFDs(self):
"""
L{_listOpenFDs} lists expected file descriptors.
"""
# This is a tricky test. A priori, there is no way to know what file
# descriptors are open now, so there is no way to know what _listOpenFDs
# should return. Work around this by creating some new file descriptors
# which we can know the state of and then just making assertions about
# their presence or absence in the result.
# Expect a file we just opened to be listed.
f = file(os.devnull)
openfds = process._listOpenFDs()
self.assertIn(f.fileno(), openfds)
# Expect a file we just closed not to be listed - with a caveat. The
# implementation may need to open a file to discover the result. That
# open file descriptor will be allocated the same number as the one we
# just closed. So, instead, create a hole in the file descriptor space
# to catch that internal descriptor and make the assertion about a
# different closed file descriptor.
# This gets allocated a file descriptor larger than f's, since nothing
# has been closed since we opened f.
fd = os.dup(f.fileno())
# But sanity check that; if it fails the test is invalid.
self.assertTrue(
fd > f.fileno(),
"Expected duplicate file descriptor to be greater than original")
try:
# Get rid of the original, creating the hole. The copy should still
# be open, of course.
f.close()
self.assertIn(fd, process._listOpenFDs())
finally:
# Get rid of the copy now
os.close(fd)
# And it should not appear in the result.
self.assertNotIn(fd, process._listOpenFDs())
def setUp(self):
self.openSockets = []
if resource is not None:
# On some buggy platforms we might leak FDs, and the test will
# fail creating the initial two sockets we *do* want to
# succeed. So, we make the soft limit the current number of fds
# plus two more (for the two sockets we want to succeed). If we've
# leaked too many fds for that to work, there's nothing we can
# do.
from twisted.internet.process import _listOpenFDs
newLimit = len(_listOpenFDs()) + 2
self.originalFileLimit = resource.getrlimit(resource.RLIMIT_NOFILE)
resource.setrlimit(resource.RLIMIT_NOFILE, (newLimit, self.originalFileLimit[1]))
self.socketLimit = newLimit + 100
def setUp(self):
self.openSockets = []
if resource is not None:
# On some buggy platforms we might leak FDs, and the test will
# fail creating the initial two sockets we *do* want to
# succeed. So, we make the soft limit the current number of fds
# plus two more (for the two sockets we want to succeed). If we've
# leaked too many fds for that to work, there's nothing we can
# do.
from twisted.internet.process import _listOpenFDs
newLimit = len(_listOpenFDs()) + 2
self.originalFileLimit = resource.getrlimit(resource.RLIMIT_NOFILE)
resource.setrlimit(resource.RLIMIT_NOFILE, (newLimit, self.originalFileLimit[1]))
self.socketLimit = newLimit + 100
def test_openFDs(self):
"""
File descriptors returned by L{_listOpenFDs} are mostly open.
This test assumes that zero-legth writes fail with EBADF on closed
file descriptors.
"""
for fd in process._listOpenFDs():
try:
fcntl.fcntl(fd, fcntl.F_GETFL)
except IOError, err:
self.assertEqual(
errno.EBADF, err.errno,
"fcntl(%d, F_GETFL) failed with unexpected errno %d" % (
fd, err.errno))
def fork(uid=None, gid=None):
settingUID = (uid is not None) or (gid is not None)
collectorEnabled = gc.isenabled()
gc.disable()
if settingUID:
curegid = os.getegid()
currgid = os.getgid()
cureuid = os.geteuid()
curruid = os.getuid()
if uid is None:
uid = cureuid
if gid is None:
gid = curegid
# Prepare to change UID in subprocess.
os.setuid(0)
os.setgid(0)
try:
pid = os.fork()
except:
# Still in the parent process.
if settingUID:
os.setregid(currgid, curegid)
os.setreuid(curruid, cureuid)
if collectorEnabled:
gc.enable()
raise
else:
if pid == 0: # pid is 0 in the child process
# do not put *ANY* code outside the try block. The
# child process must either exec or _exit. If it gets
# outside this block (due to an exception that is not
# handled here, but which might be handled higher up),
# there will be two copies of the parent running in
# parallel, doing all kinds of damage.
# After each change to this code, review it to make sure there
# are no exit paths.
try:
# Stop debugging. If I am, I don't care anymore.
sys.settrace(None)
for fd in _listOpenFDs():
if fd > 2:
try:
os.dup(fd)
except:
pass
except:
try:
stderr = os.fdopen(2, 'w')
traceback.print_exc(file=stderr)
stderr.flush()
for fd in range(3):
os.close(fd)
except:
pass # make *sure* the child terminates
else:
raise ProcessForked()
# Did you read the comment about not adding code here?
os._exit(1)
# we are now in parent process
if settingUID:
os.setregid(currgid, curegid)
os.setreuid(curruid, cureuid)
if collectorEnabled:
gc.enable()
return pid
