Add lttng_notification_channel_has_pending_notification()

[lttng-tools.git] / include / lttng / notification / channel.h

diff --git a/include/lttng/notification/channel.h b/include/lttng/notification/channel.h
index b010df12aa56b8194241fd17af947a0c8e2e1009..7708cfd56e915a293007d481f0f36c1dd8980454 100644 (file)
--- a/include/lttng/notification/channel.h
+++ b/include/lttng/notification/channel.h
@@ -18,6 +18,8 @@
 #ifndef LTTNG_NOTIFICATION_CHANNEL_H
 #define LTTNG_NOTIFICATION_CHANNEL_H
 
+#include <stdbool.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -89,6 +91,26 @@ lttng_notification_channel_get_next_notification(
                struct lttng_notification_channel *channel,
                struct lttng_notification **notification);
 
+/*
+ * Check whether a notification is pending on a notification channel.
+ *
+ * This call allows the user to check whether a notification is pending on
+ * the notification channel.
+ *
+ * If pending is set to true and the return value is
+ * LTTNG_NOTIFICATION_CHANNEL_STATUS_OK,
+ * lttng_notification_channel_get_next_notification() can be called and
+ * is guaranteed to not block.
+ *
+ * Returns LTTNG_NOTIFICATION_CHANNEL_STATUS_OK on success or
+ * LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID if an invalid parameter was
+ * provided.
+ */
+extern enum lttng_notification_channel_status
+lttng_notification_channel_has_pending_notification(
+               struct lttng_notification_channel *channel,
+               bool *notification_pending);
+
 /*
  * Subscribe to notifications of a condition through a notification channel.
  *