Merging the fixes for path cahallenge callbacks

Author: huitema

picoquic/frames.c

@@ -4762,7 +4762,7 @@ const uint8_t* picoquic_decode_path_response_frame(picoquic_cnx_t* cnx, const ui
                     }
                     picoquic_reset_path_mtu(path_x);
                 }
-                if (cnx->are_path_callbacks_enabled &&
+                if (cnx->are_path_callbacks_enabled && cnx->callback_fn != NULL &&
                     cnx->callback_fn(cnx, path_x->unique_path_id, NULL, 0, picoquic_callback_path_available,
                         cnx->callback_ctx, path_x->app_path_ctx) != 0) {
                     picoquic_connection_error_ex(cnx, PICOQUIC_TRANSPORT_INTERNAL_ERROR,
@@ -5171,7 +5171,7 @@ uint8_t* picoquic_format_ready_datagram_frame(picoquic_cnx_t* cnx, picoquic_path
         datagram_data_context.is_old_api = 0;
         datagram_data_context.was_called = 0;
 
-        if ((cnx->callback_fn)(cnx, (cnx->are_path_callbacks_enabled)?path_x->unique_path_id:0, (uint8_t*)&datagram_data_context, allowed_space,
+        if (cnx->callback_fn != NULL && (cnx->callback_fn)(cnx, (cnx->are_path_callbacks_enabled)?path_x->unique_path_id:0, (uint8_t*)&datagram_data_context, allowed_space,
             picoquic_callback_prepare_datagram, cnx->callback_ctx, NULL) != 0) {
             /* something went wrong */
             picoquic_log_app_message(cnx, "Prepare datagram returns error 0x%x", PICOQUIC_TRANSPORT_INTERNAL_ERROR);

picoquic/quicctx.c

@@ -1757,7 +1757,7 @@ void picoquic_delete_path(picoquic_cnx_t* cnx, int path_index)
     }
 
     /* Signal to the application */
-    if (cnx->are_path_callbacks_enabled &&
+    if (cnx->are_path_callbacks_enabled && cnx->callback_fn != NULL &&
         cnx->callback_fn(cnx, path_x->unique_path_id, NULL, 0, picoquic_callback_path_deleted,
         cnx->callback_ctx, path_x->app_path_ctx) != 0) {
         picoquic_connection_error_ex(cnx, PICOQUIC_TRANSPORT_INTERNAL_ERROR, 0, "Path deleted callback failed.");
@@ -1978,7 +1978,7 @@ void picoquic_set_path_challenge(picoquic_cnx_t* cnx, int path_id, uint64_t curr
         /* Reset the path challenge */
         cnx->path[path_id]->first_tuple->challenge_required = 1;
         picoquic_set_tuple_challenge(cnx->path[path_id]->first_tuple, current_time, cnx->quic->use_constant_challenges);
-        if (cnx->path[path_id]->first_tuple->challenge_verified && cnx->are_path_callbacks_enabled) {
+        if (cnx->path[path_id]->first_tuple->challenge_verified && cnx->are_path_callbacks_enabled && cnx->callback_fn != NULL) {
             if (cnx->callback_fn(cnx, cnx->path[path_id]->unique_path_id, NULL, 0, picoquic_callback_path_suspended,
                 cnx->callback_ctx, cnx->path[path_id]->app_path_ctx) != 0) {
                 picoquic_connection_error(cnx, PICOQUIC_TRANSPORT_INTERNAL_ERROR, picoquic_frame_type_path_challenge);