trigger: introduce firing policies

[lttng-tools.git] / include / lttng / trigger / trigger.h

diff --git a/include/lttng/trigger/trigger.h b/include/lttng/trigger/trigger.h
index e92897fd541e79accfeac412393dd780e1014a4d..a0c312ddd1e92e2efdb94c6affcbb942696198ff 100644 (file)
--- a/include/lttng/trigger/trigger.h
+++ b/include/lttng/trigger/trigger.h
@@ -9,10 +9,13 @@
 #define LTTNG_TRIGGER_H
 
 #include <sys/types.h>
+#include <inttypes.h>
 
 struct lttng_action;
 struct lttng_condition;
 struct lttng_trigger;
+/* A set of triggers. */
+struct lttng_triggers;
 
 #ifdef __cplusplus
 extern "C" {
@@ -33,6 +36,11 @@ enum lttng_trigger_status {
        LTTNG_TRIGGER_STATUS_PERMISSION_DENIED = -6,
 };
 
+enum lttng_trigger_firing_policy {
+       LTTNG_TRIGGER_FIRING_POLICY_EVERY_N = 0,
+       LTTNG_TRIGGER_FIRING_POLICY_ONCE_AFTER_N = 1,
+};
+
 /*
  * Create a trigger object associating a condition and an action.
  *
@@ -96,6 +104,66 @@ extern struct lttng_condition *lttng_trigger_get_condition(
 extern struct lttng_action *lttng_trigger_get_action(
                struct lttng_trigger *trigger);
 
+
+/*
+ * Get the name of a trigger.
+ *
+ * The caller does not assume the ownership of the returned name.
+ * The name shall only only be used for the duration of the trigger's
+ * lifetime, or until a different name is set.
+ *
+ * Returns LTTNG_TRIGGER_STATUS_OK and a pointer to the trigger's name on
+ * success, LTTNG_TRIGGER_STATUS_INVALID if an invalid parameter is passed,
+ * or LTTNG_TRIGGER_STATUS_UNSET if a name was not set prior to this call.
+ */
+extern enum lttng_trigger_status lttng_trigger_get_name(
+               const struct lttng_trigger *trigger, const char **name);
+
+/*
+ * Set the trigger name.
+ *
+ * A name is optional.
+ * A name will be assigned on trigger registration if no name is set.
+ *
+ * The name is copied.
+ *
+ * Return LTTNG_TRIGGER_STATUS_OK on success, LTTNG_TRIGGER_STATUS_INVALID
+ * if invalid parameters are passed.
+ */
+extern enum lttng_trigger_status lttng_trigger_set_name(
+               struct lttng_trigger *trigger, const char *name);
+
+/*
+ * Set the trigger firing policy.
+ *
+ * This is optional. By default a trigger is set to fire each time the
+ * associated condition occurs.
+ *
+ * Threshold is the number of times the condition must be hit before the policy
+ * is enacted.
+ *
+ * Return LTTNG_TRIGGER_STATUS_OK on success, LTTNG_TRIGGER_STATUS_INVALID
+ * if invalid parameters are passed.
+ */
+extern enum lttng_trigger_status lttng_trigger_set_firing_policy(
+               struct lttng_trigger *trigger,
+               enum lttng_trigger_firing_policy policy_type,
+               uint64_t threshold);
+
+/*
+ * Get the trigger firing policy.
+ *
+ * Threshold is the number of time the condition must be hit before the policy is
+ * enacted.
+ *
+ * Return LTTNG_TRIGGER_STATUS_OK on success, LTTNG_TRIGGER_STATUS_INVALID
+ * if invalid parameters are passed.
+ */
+extern enum lttng_trigger_status lttng_trigger_get_firing_policy(
+               const struct lttng_trigger *trigger,
+               enum lttng_trigger_firing_policy *policy_type,
+               uint64_t *threshold);
+
 /*
  * Destroy (frees) a trigger object.
  */
@@ -119,6 +187,33 @@ extern int lttng_register_trigger(struct lttng_trigger *trigger);
  */
 extern int lttng_unregister_trigger(struct lttng_trigger *trigger);
 
+/*
+ * Get a trigger from the set at a given index.
+ *
+ * Note that the trigger set maintains the ownership of the returned trigger.
+ * It must not be destroyed by the user, nor should a reference to it be held
+ * beyond the lifetime of the trigger set.
+ *
+ * Returns a trigger, or NULL on error.
+ */
+extern const struct lttng_trigger *lttng_triggers_get_at_index(
+               const struct lttng_triggers *triggers, unsigned int index);
+
+/*
+ * Get the number of triggers in a trigger set.
+ *
+ * Return LTTNG_TRIGGER_STATUS_OK on success,
+ * LTTNG_TRIGGER_STATUS_INVALID when invalid parameters are passed.
+ */
+extern enum lttng_trigger_status lttng_triggers_get_count(
+               const struct lttng_triggers *triggers, unsigned int *count);
+
+/*
+ * Destroy a trigger set.
+ */
+extern void lttng_triggers_destroy(struct lttng_triggers *triggers);
+
+
 #ifdef __cplusplus
 }
 #endif