bus: when parsing signature strings, accept NULL as empty signature

diff --git a/src/libsystemd-bus/bus-message.c b/src/libsystemd-bus/bus-message.c
index 7acab50979336b4e464dc9f0b403bac6a221af05..2d051e8aeb97fafeabf63f3e18ec11a689df7552 100644 (file)
--- a/src/libsystemd-bus/bus-message.c
+++ b/src/libsystemd-bus/bus-message.c
@@ -1250,7 +1250,9 @@ int bus_message_append_ap(
         int r;
 
         assert(m);
-        assert(types);
+
+        if (!types)
+                return 0;
 
         for (t = types; *t; t++) {
                 switch (*t) {