Relayd data available command support

[lttng-tools.git] / src / lib / lttng-ctl / lttng-ctl.c

diff --git a/src/lib/lttng-ctl/lttng-ctl.c b/src/lib/lttng-ctl/lttng-ctl.c
index edaebf59c8654515ac7872d0888e4a84dd6ab0ad..c6238e11c81e17b746553725d2d062d67a22d2d3 100644 (file)
--- a/src/lib/lttng-ctl/lttng-ctl.c
+++ b/src/lib/lttng-ctl/lttng-ctl.c
@@ -1590,6 +1590,38 @@ int _lttng_create_session_ext(const char *name, const char *url,
                        NULL);
 }
 
+/*
+ * For a given session name, this call checks if the data is ready to be read
+ * or is still being extracted by the consumer(s) hence not ready to be used by
+ * any readers.
+ */
+int lttng_data_available(const char *session_name)
+{
+       int ret;
+       struct lttcomm_session_msg lsm;
+
+       if (session_name == NULL) {
+               return -LTTNG_ERR_INVALID;
+       }
+
+       lsm.cmd_type = LTTNG_DATA_AVAILABLE;
+
+       copy_string(lsm.session.name, session_name, sizeof(lsm.session.name));
+
+       ret = ask_sessiond(&lsm, NULL);
+
+       /*
+        * The ask_sessiond function negate the return code if it's not LTTNG_OK so
+        * getting -1 means that the reply ret_code was 1 thus meaning that the
+        * data is available. Yes it is hackish but for now this is the only way.
+        */
+       if (ret == -1) {
+               ret = 1;
+       }
+
+       return ret;
+}
+
 /*
  * lib constructor
  */