include/lttng/notification/notification.h

   1 /*
   2  * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * This library is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU Lesser General Public License, version 2.1 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This library is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
  11  * for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this library; if not, write to the Free Software Foundation,
  15  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  16  */
  17
  18 #ifndef LTTNG_NOTIFICATION_H
  19 #define LTTNG_NOTIFICATION_H
  20
  21 #ifdef __cplusplus
  22 extern "C" {
  23 #endif
  24
  25 struct lttng_condition;
  26 struct lttng_evaluation;
  27 struct lttng_notification;
  28
  29 /*
  30  * Get a notification's condition.
  31  *
  32  * The notification retains the ownership of both the condition and evaluation
  33  * objects. Hence, it is not valid to access those objects after the destruction
  34  * of their associated notification.
  35  *
  36  * The caller should check the condition's type in order to use the appropriate
  37  * specialized functions to access the condition's properties.
  38  *
  39  * Returns an lttng_condition object on success, NULL on error.
  40  */
  41 extern const struct lttng_condition *lttng_notification_get_condition(
  42                 struct lttng_notification *notification);
  43
  44 /*
  45  * Get a notification's condition's evaluation.
  46  *
  47  * The notification retains the ownership of the evaluation object. Hence, it is
  48  * not valid to access that object after the destruction of its associated
  49  * notification.
  50  *
  51  * The caller should check the evaluation's type in order to use the appropriate
  52  * specialized functions to access the evaluation's properties.
  53  *
  54  * Returns an lttng_evaluation object on success, NULL on error.
  55  */
  56 extern const struct lttng_evaluation *lttng_notification_get_evaluation(
  57                 struct lttng_notification *notification);
  58
  59 /*
  60  * Destroys (frees) a notification. The notification's condition and evaluation
  61  * are destroyed as a side-effect.
  62  */
  63 extern void lttng_notification_destroy(struct lttng_notification *notification);
  64
  65 #ifdef __cplusplus
  66 }
  67 #endif
  68
  69 #endif /* LTTNG_NOTIFICATION_H */