trigger: keep state of if a trigger is currently registered

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

diff --git a/include/lttng/trigger/trigger-internal.h b/include/lttng/trigger/trigger-internal.h
index c5ee9c64b4c1db9642251417fa812f3e18a9a68d..f16b68d00fd88412af0e649e02aef3447b434c11 100644 (file)
--- a/include/lttng/trigger/trigger-internal.h
+++ b/include/lttng/trigger/trigger-internal.h
@@ -8,13 +8,14 @@
 #ifndef LTTNG_TRIGGER_INTERNAL_H
 #define LTTNG_TRIGGER_INTERNAL_H
 
 #ifndef LTTNG_TRIGGER_INTERNAL_H
 #define LTTNG_TRIGGER_INTERNAL_H
 

-#include <lttng/trigger/trigger.h>

 #include <common/credentials.h>
 #include <common/dynamic-array.h>
 #include <common/macros.h>
 #include <common/optional.h>
 #include <common/credentials.h>
 #include <common/dynamic-array.h>
 #include <common/macros.h>
 #include <common/optional.h>

-#include <stdint.h>
+#include <lttng/trigger/trigger.h>
+#include <pthread.h>

 #include <stdbool.h>
 #include <stdbool.h>

+#include <stdint.h>

 #include <sys/types.h>
 #include <urcu/ref.h>
 
 #include <sys/types.h>
 #include <urcu/ref.h>
 


@@ -36,6 +37,25 @@ struct lttng_trigger {
         * notification.
         */
        LTTNG_OPTIONAL(uint64_t) tracer_token;
         * notification.
         */
        LTTNG_OPTIONAL(uint64_t) tracer_token;

+
+       /*
+        * Is the trigger registered?
+        *
+        * This is necessary since a reference holder might be interested in the
+        * overall state of the trigger from the point of view of its owner.
+        *
+        * The main user is the action executor since we want to prevent the
+        * execution of actions related to a trigger that is unregistered.
+        *
+        * Not considered for `is_equal`.
+        */
+       bool registered;
+
+       /*
+        * The lock is used to protect against concurrent trigger execution and
+        * trigger removal.
+        */
+       pthread_mutex_t lock;

 };
 
 struct lttng_triggers {
 };
 
 struct lttng_triggers {


@@ -182,4 +202,28 @@ struct lttng_trigger *lttng_trigger_copy(const struct lttng_trigger *trigger);
 LTTNG_HIDDEN
 bool lttng_trigger_needs_tracer_notifier(const struct lttng_trigger *trigger);
 
 LTTNG_HIDDEN
 bool lttng_trigger_needs_tracer_notifier(const struct lttng_trigger *trigger);
 

+LTTNG_HIDDEN
+void lttng_trigger_set_as_registered(struct lttng_trigger *trigger);
+
+LTTNG_HIDDEN
+void lttng_trigger_set_as_unregistered(struct lttng_trigger *trigger);
+
+/*
+ * The trigger must be locked before calling lttng_trigger_is_registered.
+ *
+ * The lock is necessary since a trigger can be unregistered at any time.
+ *
+ * Manipulations requiring that the trigger be registered must always acquire
+ * the trigger lock for the duration of the manipulation using
+ * `lttng_trigger_lock` and `lttng_trigger_unlock`.
+ */
+LTTNG_HIDDEN
+bool lttng_trigger_is_registered(struct lttng_trigger *trigger);
+
+LTTNG_HIDDEN
+void lttng_trigger_lock(struct lttng_trigger *trigger);
+
+LTTNG_HIDDEN
+void lttng_trigger_unlock(struct lttng_trigger *trigger);
+

 #endif /* LTTNG_TRIGGER_INTERNAL_H */
 #endif /* LTTNG_TRIGGER_INTERNAL_H */