res_pjsip_session.c: Add some helpful comments and minor tweaks.

Change-Id: I742aeeaf5f760593f323a00fb691affe22e35743

diff --git a/res/res_pjsip_session.c b/res/res_pjsip_session.c
index e6ed64520a48a8c2164cb8795cabac6ec0434354..f2f2fc968dce179694f1a21f779834c0fcd81c8c 100644 (file)
--- a/res/res_pjsip_session.c
+++ b/res/res_pjsip_session.c
@@ -1212,8 +1212,9 @@ static int add_supplements(struct ast_sip_session *session)
 static int add_session_media(void *obj, void *arg, int flags)
 {
        struct sdp_handler_list *handler_list = obj;
-       struct ast_sip_session * session = arg;
+       struct ast_sip_session *session = arg;
        RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
+
        session_media = ao2_alloc(sizeof(*session_media) + strlen(handler_list->stream_type), session_media_dtor);
        if (!session_media) {
                return CMP_STOP;
@@ -1253,9 +1254,11 @@ struct ast_sip_channel_pvt *ast_sip_channel_pvt_alloc(void *pvt, struct ast_sip_
 struct ast_sip_session *ast_sip_session_alloc(struct ast_sip_endpoint *endpoint,
        struct ast_sip_contact *contact, pjsip_inv_session *inv_session)
 {
-       RAII_VAR(struct ast_sip_session *, session, ao2_alloc(sizeof(*session), session_destructor), ao2_cleanup);
+       RAII_VAR(struct ast_sip_session *, session, NULL, ao2_cleanup);
        struct ast_sip_session_supplement *iter;
        int dsp_features = 0;
+
+       session = ao2_alloc(sizeof(*session), session_destructor);
        if (!session) {
                return NULL;
        }
@@ -1296,6 +1299,7 @@ struct ast_sip_session *ast_sip_session_alloc(struct ast_sip_endpoint *endpoint,
 
        if (dsp_features) {
                if (!(session->dsp = ast_dsp_new())) {
+                       /* Release the ref held by session->inv_session */
                        ao2_ref(session, -1);
                        return NULL;
                }
@@ -1304,6 +1308,7 @@ struct ast_sip_session *ast_sip_session_alloc(struct ast_sip_endpoint *endpoint,
        }
 
        if (add_supplements(session)) {
+               /* Release the ref held by session->inv_session */
                ao2_ref(session, -1);
                return NULL;
        }
@@ -2280,6 +2285,8 @@ static int session_end_completion(void *vsession)
 
        ast_sip_dialog_set_serializer(session->inv_session->dlg, NULL);
        ast_sip_dialog_set_endpoint(session->inv_session->dlg, NULL);
+
+       /* Now we can release the ref that was held by session->inv_session */
        ao2_cleanup(session);
        return 0;
 }