client: not allow adding handler twicenot allow

Change-Id: Ibc42a95295638ccc87aba5eb6999ef73664be7b2

diff --git a/client/tdm_client.c b/client/tdm_client.c
index 41a5fe2..468d984 100644 (file)
--- a/client/tdm_client.c
+++ b/client/tdm_client.c
@@ -751,6 +751,13 @@ tdm_client_output_add_change_handler(tdm_client_output *output,
        private_output = (tdm_private_client_output*)output;
        private_client = private_output->private_client;
 
+       LIST_FOR_EACH_ENTRY(h, &private_output->change_handler_list, link) {
+               if (h->func == func && h->user_data == user_data) {
+                       TDM_ERR("can't add twice");
+                       return TDM_ERROR_BAD_REQUEST;
+               }
+       }
+
        h = calloc(1, sizeof *h);
        TDM_RETURN_VAL_IF_FAIL(h != NULL, TDM_ERROR_OUT_OF_MEMORY);