+ /* Agent domains. */
+ struct agent *agt = agent_find_by_event_notifier_domain(
+ trigger_domain);
+
+ /*
+ * This trigger was never registered in the first place. Calling
+ * this function under those circumstances is an internal error.
+ */
+ assert(agt);
+ ret_code = trigger_agent_disable(trigger, agt);
+ if (ret_code != LTTNG_OK) {
+ goto end_unlock_session_list;
+ }
+
+ break;
+ }
+ case LTTNG_DOMAIN_NONE:
+ default:
+ abort();
+ }
+
+ ret_code = LTTNG_OK;
+
+end_unlock_session_list:
+ session_unlock_list();
+ return ret_code;
+}
+
+enum lttng_error_code cmd_unregister_trigger(const struct lttng_credentials *cmd_creds,
+ const struct lttng_trigger *trigger,
+ struct notification_thread_handle *notification_thread)
+{
+ enum lttng_error_code ret_code;
+ const char *trigger_name;
+ uid_t trigger_owner;
+ enum lttng_trigger_status trigger_status;
+ struct lttng_trigger *sessiond_trigger = NULL;
+
+ trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
+ trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ? trigger_name : "(anonymous)";
+ trigger_status = lttng_trigger_get_owner_uid(trigger, &trigger_owner);
+ assert(trigger_status == LTTNG_TRIGGER_STATUS_OK);
+
+ DBG("Running unregister trigger command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
+ trigger_name, (int) trigger_owner,
+ (int) lttng_credentials_get_uid(cmd_creds));
+
+ /*
+ * Validate the trigger credentials against the command credentials.
+ * Only the root user can unregister a trigger with non-matching
+ * credentials.
+ */
+ if (!lttng_credentials_is_equal_uid(
+ lttng_trigger_get_credentials(trigger),
+ cmd_creds)) {
+ if (lttng_credentials_get_uid(cmd_creds) != 0) {
+ ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
+ trigger_name, (int) trigger_owner,
+ (int) lttng_credentials_get_uid(cmd_creds));
+ ret_code = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+ }
+
+ /* Fetch the sessiond side trigger object. */
+ ret_code = notification_thread_command_get_trigger(
+ notification_thread, trigger, &sessiond_trigger);
+ if (ret_code != LTTNG_OK) {
+ DBG("Failed to get trigger from notification thread during unregister: trigger name = '%s', trigger owner uid = %d, error code = %d",
+ trigger_name, (int) trigger_owner, ret_code);
+ goto end;
+ }
+
+ assert(sessiond_trigger);
+
+ /*
+ * From this point on, no matter what, consider the trigger
+ * unregistered.
+ *
+ * We set the unregistered state of the sessiond side trigger object in
+ * the client thread since we want to minimize the possibility of the
+ * notification thread being stalled due to a long execution of an
+ * action that required the trigger lock.
+ */
+ lttng_trigger_set_as_unregistered(sessiond_trigger);
+
+ ret_code = notification_thread_command_unregister_trigger(notification_thread,
+ trigger);
+ if (ret_code != LTTNG_OK) {
+ DBG("Failed to unregister trigger from notification thread: trigger name = '%s', trigger owner uid = %d, error code = %d",
+ trigger_name, (int) trigger_owner, ret_code);
+ goto end;
+ }
+
+ /*
+ * Synchronize tracers if the trigger removes an event notifier.
+ * Do this even if the trigger unregistration failed to at least stop
+ * the tracers from producing notifications associated with this
+ * event notifier.
+ */
+ if (lttng_trigger_needs_tracer_notifier(trigger)) {
+ ret_code = synchronize_tracer_notifier_unregister(trigger);
+ if (ret_code != LTTNG_OK) {
+ ERR("Error unregistering trigger to tracer.");