stasis_state: Make unsubscribes NULL tolerant

Regular stasis unsubscribes can handle NULL subscription objects. This patch
makes it so stasis state unsubscribes handles NULL's as well.

ASTERISK-28442

Change-Id: Ic3648e8df043a85b77cff085e9ff10356028e479

diff --git a/main/stasis_state.c b/main/stasis_state.c
index 2a9afcb717fc3b320cf0bf1ace9633a7ee25bc52..a9159724d04afc953a9b6fe59be613c06839fae8 100644 (file)
--- a/main/stasis_state.c
+++ b/main/stasis_state.c
@@ -514,8 +514,11 @@ void *stasis_state_unsubscribe(struct stasis_state_subscriber *sub)
 
 void *stasis_state_unsubscribe_and_join(struct stasis_state_subscriber *sub)
 {
-       sub->stasis_sub = stasis_unsubscribe_and_join(sub->stasis_sub);
-       ao2_ref(sub, -1);
+       if (sub) {
+               sub->stasis_sub = stasis_unsubscribe_and_join(sub->stasis_sub);
+               ao2_ref(sub, -1);
+       }
+
        return NULL;
 }