actions: introduce action group

[lttng-tools.git] / include / lttng / action / group.h

diff --git a/include/lttng/action/group.h b/include/lttng/action/group.h
new file mode 100644 (file)
index 0000000..af1e732
--- /dev/null
+++ b/include/lttng/action/group.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2019 Simon Marchi <simon.marchi@efficios.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ */
+
+#ifndef LTTNG_ACTION_GROUP_H
+#define LTTNG_ACTION_GROUP_H
+
+struct lttng_action;
+struct lttng_action_group;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Create a newly allocated action group object.
+ *
+ * Returns a new action group on success, NULL on failure. This action group
+ * must be destroyed using lttng_action_group_destroy().
+ */
+extern struct lttng_action *lttng_action_group_create(void);
+
+/*
+ * Add an action to an lttng_action object of type LTTNG_ACTION_GROUP.
+ *
+ * The action group acquires a reference to the action. The action can be
+ * safely destroyed after calling this function. An action must not be
+ * modified after adding it to a group.
+ *
+ * Adding an action group to an action group is not supported.
+ */
+extern enum lttng_action_status lttng_action_group_add_action(
+               struct lttng_action *group, struct lttng_action *action);
+
+/*
+ * Get the number of actions in an action group.
+ */
+extern enum lttng_action_status lttng_action_group_get_count(
+               const struct lttng_action *group, unsigned int *count);
+
+/*
+ * Get an action from the action group at a given index.
+ *
+ * Note that the group maintains the ownership of the returned action.
+ * It must not be destroyed by the user, nor should it be held beyond
+ * the lifetime of the action group.
+ *
+ * Returns an action, or NULL on error.
+ */
+extern const struct lttng_action *lttng_action_group_get_at_index(
+               const struct lttng_action *group,
+               unsigned int index);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LTTNG_ACTION_GROUP_H */