def spawn(self):
self.set_post_defaults()
self.plash_setup()
if plash.env.under_plash:
my_execve = kernel_execve
else:
my_execve = os.execve
assert isinstance(self.cmd, str)
for arg in [self.arg0] + self.args:
assert isinstance(arg, str)
# Doing this in Python is a little risky. We must ensure that
# no freeing of Plash objects occurs before the call to
# cap_close_all_connections() in the newly-forked process,
# otherwise both processes could try to use the same connection
# to send the "Drop" message, leading to a protocol violation.
# We're probably OK with the refcounting C implementation of
# Python, but another implementation might do GC at any point.
pid = os.fork()
if pid == 0:
try:
plash_core.cap_close_all_connections()
if plash.env.under_plash:
# Unset this variable so that the connection
# does not get reinstated after resetting it.
if "PLASH_COMM_FD" in os.environ:
del os.environ["PLASH_COMM_FD"]
# This lets us close() the FD for libc's connection.
plash_core.libc_reset_connection()
self._set_up_fds()
try:
my_execve(self.cmd, [self.arg0] + self.args, self.env)
except Exception, ex:
os.write(STDERR_FILENO, "execve failed: %s: %s\n"
% (type(ex).__name__, str(ex)))
finally:
os._exit(1)
else:
# We must drop our references to the client's FDs so that
# we do not hold its connections open even after the
# client has exited.
self.fds.clear()
return pid
def tearDown(self):
super(CapProtocolCTests, self).tearDown()
plash_core.cap_close_all_connections()
self.assertFalse(plash_core.cap_server_exporting())
def tearDown(self):
self._temp_maker.destroy()
plash_core.cap_close_all_connections()
