Fixed #1062 (Assertion if 200/OK INVITE response is received during PJSUA-LIB destroy sequence)


git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@3153 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/pjsip/src/pjsua-lib/pjsua_media.c b/pjsip/src/pjsua-lib/pjsua_media.c
index 234833b..c0a7c3c 100644
--- a/pjsip/src/pjsua-lib/pjsua_media.c
+++ b/pjsip/src/pjsua-lib/pjsua_media.c
@@ -1476,6 +1476,11 @@
     pjmedia_port *media_port;
     pj_status_t status;
 
+    if (!pjsua_var.med_endpt) {
+	/* We're being shutdown */
+	return PJ_EBUSY;
+    }
+
     /* Destroy existing media session, if any. */
     prev_media_st = call->media_st;
     stop_media_session(call->index);