Fix to issue ros2#1179 (ros2#1180)

* Fix to issue ros2#1179

Signed-off-by: KKSTB <[email protected]>

rclpy/rclpy/wait_for_message.py

@@ -39,23 +39,27 @@ def wait_for_message(
  wait_set.clear_entities()
 
  sub = node.create_subscription(msg_type, topic, lambda _: None, 1)
- wait_set.add_subscription(sub.handle)
- sigint_gc = SignalHandlerGuardCondition(context=context)
- wait_set.add_guard_condition(sigint_gc.handle)
+ try:
+ wait_set.add_subscription(sub.handle)
+ sigint_gc = SignalHandlerGuardCondition(context=context)
+ wait_set.add_guard_condition(sigint_gc.handle)
 
- timeout_nsec = timeout_sec_to_nsec(time_to_wait)
- wait_set.wait(timeout_nsec)
+  timeout_nsec = timeout_sec_to_nsec(time_to_wait)
+  wait_set.wait(timeout_nsec)
 
- subs_ready = wait_set.get_ready_entities('subscription')
- guards_ready = wait_set.get_ready_entities('guard_condition')
+  subs_ready = wait_set.get_ready_entities('subscription')
+  guards_ready = wait_set.get_ready_entities('guard_condition')
 
- if guards_ready:
- if sigint_gc.handle.pointer in guards_ready:
- return (False, None)
+  if guards_ready:
+  if sigint_gc.handle.pointer in guards_ready:
+  return False, None
 
- if subs_ready:
- if sub.handle.pointer in subs_ready:
- msg_info = sub.handle.take_message(sub.msg_type, sub.raw)
- return (True, msg_info[0])
+ if subs_ready:
+ if sub.handle.pointer in subs_ready:
+ msg_info = sub.handle.take_message(sub.msg_type, sub.raw)
+ if msg_info is not None:
+ return True, msg_info[0]
+ finally:
+ node.destroy_subscription(sub)
 
- return (False, None)
+ return False, None