Lib lttng-ctl data available command support

[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index b1e66e755bf0f621fb8c78f84a6d8c9043cedc55..1d4f9264eb0a57e4aedfa595767b1478b9402a4f 100644 (file)
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -2334,6 +2334,47 @@ error:
        return ret;
 }
 
+/*
+ * Command LTTNG_DATA_AVAILABLE returning 0 if the data is NOT ready to be read
+ * or else 1 if the data is available for trace analysis.
+ */
+int cmd_data_available(struct ltt_session *session)
+{
+       int ret;
+       struct ltt_kernel_session *ksess = session->kernel_session;
+       struct ltt_ust_session *usess = session->ust_session;
+
+       assert(session);
+
+       /* Session MUST be stopped to ask for data availability. */
+       if (session->enabled) {
+               ret = LTTNG_ERR_SESSION_STARTED;
+               goto error;
+       }
+
+       if (ksess && ksess->consumer) {
+               ret = consumer_is_data_available(ksess->id, ksess->consumer);
+               if (ret == 0) {
+                       /* Data is still being extracted for the kernel. */
+                       goto error;
+               }
+       }
+
+       if (usess && usess->consumer) {
+               ret = consumer_is_data_available(usess->id, usess->consumer);
+               if (ret == 0) {
+                       /* Data is still being extracted for the kernel. */
+                       goto error;
+               }
+       }
+
+       /* Data is ready to be read by a viewer */
+       ret = 1;
+
+error:
+       return ret;
+}
+
 /*
  * Init command subsystem.
  */