update callback wrapper to support bus 2.02.0

Signed-off-by: Mattias Andrée <maandree@operamail.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/src/native_bus.pyx b/src/native_bus.pyx
index 5cc425c..de33e91 100644
--- a/src/native_bus.pyx
+++ b/src/native_bus.pyx
@@ -201,9 +201,13 @@ def bus_write_wrapped(bus : int, message : str) -> int:
 
 
 cdef int bus_callback_wrapper(const char *message, user_data):
-    cdef bytes bs = message
+    cdef bytes bs
     callback, user_data = tuple(<object>user_data)
-    return <int>callback(bs, user_data)
+    if message is NULL:
+        return <int>callback(None, user_data)
+    else:
+        bs = message
+        return <int>callback(bs, user_data)
 
 
 def bus_read_wrapped(bus : int, callback : callable, user_data) -> int: