This file is part of GNUnet
Copyright (C) 2009-2016 GNUnet e.V.
- GNUnet is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 3, or (at your
- option) any later version.
+ GNUnet is free software: you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published
+ by the Free Software Foundation, either version 3 of the License,
+ or (at your option) any later version.
GNUnet is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA.
+ Affero General Public License for more details.
*/
/**
/**
- * Function called by the driver to tell the scheduler to run some of
- * the tasks that are ready. This function may return even though
- * there are tasks left to run just to give other tasks a chance as
- * well. If we return #GNUNET_YES, the driver should call this
- * function again as soon as possible, while if we return #GNUNET_NO
- * it must block until either the operating system has more work (the
- * scheduler has no more work to do right now) or the timeout set by
- * the scheduler (using the set_wakeup callback) is reached.
+ * Function called by external event loop implementations to tell the
+ * scheduler to run some of the tasks that are ready. Must be called
+ * only after #GNUNET_SCHEDULER_driver_init has been called and before
+ * #GNUNET_SCHEDULER_driver_done is called.
+ * This function may return even though there are tasks left to run
+ * just to give other tasks a chance as well. If we return #GNUNET_YES,
+ * the event loop implementation should call this function again as
+ * soon as possible, while if we return #GNUNET_NO it must block until
+ * either the operating system has more work (the scheduler has no more
+ * work to do right now) or the timeout set by the scheduler (using the
+ * set_wakeup callback) is reached.
*
- * @param sh scheduler handle that was given to the `loop`
- * @return #GNUNET_OK if there are more tasks that are ready,
- * and thus we would like to run more (yield to avoid
- * blocking other activities for too long)
- * #GNUNET_NO if we are done running tasks (yield to block)
- * #GNUNET_SYSERR on error, e.g. no tasks were ready
+ * @param sh scheduler handle that was returned by
+ * #GNUNET_SCHEDULER_driver_init
+ * @return #GNUNET_YES if there are more tasks that are ready,
+ * and thus we would like to run more (yield to avoid
+ * blocking other activities for too long) #GNUNET_NO
+ * if we are done running tasks (yield to block)
*/
int
-GNUNET_SCHEDULER_run_from_driver (struct GNUNET_SCHEDULER_Handle *sh);
+GNUNET_SCHEDULER_do_work (struct GNUNET_SCHEDULER_Handle *sh);
/**
- * API a driver has to implement for
- * #GNUNET_SCHEDULER_run_with_driver().
+ * API an external event loop has to implement for
+ * #GNUNET_SCHEDULER_driver_init.
*/
struct GNUNET_SCHEDULER_Driver
{
(*set_wakeup)(void *cls,
struct GNUNET_TIME_Absolute dt);
- /**
- * Event loop's "main" function, to be called from
- * #GNUNET_SCHEDULER_run_with_driver() to actually
- * launch the loop. The loop should run as long as
- * tasks (added by the add callback) are available
- * OR the wakeup time (added by the set_wakeup
- * callback) is not FOREVER.
- *
- * @param cls closure
- * @param sh scheduler handle to pass to
- * #GNUNET_SCHEDULER_run_from_driver()
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
- */
- int
- (*loop)(void *cls,
- struct GNUNET_SCHEDULER_Handle *sh);
-
};
/**
- * Initialize and run scheduler. This function will return when all
- * tasks have completed. On systems with signals, receiving a SIGTERM
- * (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown
- * to be run after the active task is complete. As a result, SIGTERM
- * causes all shutdown tasks to be scheduled with reason
- * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added
- * afterwards will execute normally!). Note that any particular
- * signal will only shut down one scheduler; applications should
- * always only create a single scheduler.
+ * Function called by external event loop implementations to initialize
+ * the scheduler. An external implementation has to provide @a driver
+ * which contains callbacks for the scheduler (see definition of struct
+ * #GNUNET_SCHEDULER_Driver). The callbacks are used to instruct the
+ * external implementation to watch for events. If it detects any of
+ * those events it is expected to call #GNUNET_SCHEDULER_do_work to let
+ * the scheduler handle it. If an event is related to a specific task
+ * (e.g. the scheduler gave instructions to watch a file descriptor),
+ * the external implementation is expected to mark that task ready
+ * before by calling #GNUNET_SCHEDULER_task_ready.
*
- * @param driver drive to use for the event loop
- * @param task task to run first (and immediately)
- * @param task_cls closure of @a task
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
+ * This function has to be called before any tasks are scheduled and
+ * before GNUNET_SCHEDULER_do_work is called for the first time. It
+ * allocates resources that have to be freed again by calling
+ * #GNUNET_SCHEDULER_driver_done.
+ *
+ * This function installs the same signal handlers as
+ * #GNUNET_SCHEDULER_run. This means SIGTERM (and other similar signals)
+ * will induce a call to #GNUNET_SCHEDULER_shutdown during the next
+ * call to #GNUNET_SCHEDULER_do_work. As a result, SIGTERM causes all
+ * active tasks to be scheduled with reason
+ * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added afterwards
+ * will execute normally!). Note that any particular signal will only
+ * shut down one scheduler; applications should always only create a
+ * single scheduler.
+ *
+ * @param driver to use for the event loop
+ * @return handle to be passed to #GNUNET_SCHEDULER_do_work and
+ * #GNUNET_SCHEDULER_driver_done
*/
-int
-GNUNET_SCHEDULER_run_with_driver (const struct GNUNET_SCHEDULER_Driver *driver,
- GNUNET_SCHEDULER_TaskCallback task,
- void *task_cls);
+struct GNUNET_SCHEDULER_Handle *
+GNUNET_SCHEDULER_driver_init (const struct GNUNET_SCHEDULER_Driver *driver);
+
+
+/**
+ * Counter-part of #GNUNET_SCHEDULER_driver_init. Has to be called
+ * by external event loop implementations after the scheduler has
+ * shut down. This is the case if both of the following conditions
+ * are met:
+ *
+ * - all tasks the scheduler has added through the driver's add
+ * callback have been removed again through the driver's del
+ * callback
+ * - the timeout the scheduler has set through the driver's
+ * add_wakeup callback is FOREVER
+ *
+ * @param sh the handle returned by #GNUNET_SCHEDULER_driver_init
+ */
+void
+GNUNET_SCHEDULER_driver_done (struct GNUNET_SCHEDULER_Handle *sh);
/**
/**
* Cancel the task with the specified identifier.
- * The task must not yet have run.
+ * The task must not yet have run. Only allowed to be called as long as the
+ * scheduler is running, that is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param task id of the task to cancel
- * @return the closure of the callback of the cancelled task
+ * @return original closure of the task
*/
void *
GNUNET_SCHEDULER_cancel (struct GNUNET_SCHEDULER_Task *task);
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready. It will be run with the DEFAULT priority.
+ * Only allowed to be called as long as the scheduler is running, that
+ * is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param rfd read file-descriptor
* socket being ready. The task will be scheduled for execution once
* either the delay has expired or the socket operation is ready. It
* will be run with the DEFAULT priority.
+ * Only allowed to be called as long as the scheduler is running, that
+ * is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param priority priority to use for the task
* specified file descriptor is ready for writing. The delay can be
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
- * socket operation is ready. It will be run with the DEFAULT priority.
+ * socket operation is ready. It will be run with the priority of
+ * the calling task.
+ * Only allowed to be called as long as the scheduler is running, that
+ * is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
- * * @param delay when should this operation time out?
+ * @param delay when should this operation time out?
* @param wfd write file-descriptor
* @param task main function of the task
* @param task_cls closure of @a task
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready.
+ * Only allowed to be called as long as the scheduler is running, that
+ * is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param priority priority of the task
* @param on_read whether to poll the file-descriptor for readability
* @param on_write whether to poll the file-descriptor for writability
* @param task main function of the task
- * @param task_cls closure of @a task
+ * @param task_cls closure of task
* @return unique task identifier for the job
* only valid until "task" is started!
*/
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
+
/**
* Schedule a new task to be run with a specified delay or when the
* specified file descriptor is ready for reading. The delay can be
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready. It will be run with the DEFAULT priority.
+ * Only allowed to be called as long as the scheduler is running, that
+ * is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
- * * @param delay when should this operation time out?
+ * @param delay when should this operation time out?
* @param rfd read file-descriptor
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
- * only valid until "task" is started!
+ * only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay,
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready. It will be run with the DEFAULT priority.
+ * Only allowed to be called as long as the scheduler is running, that
+ * is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
- * * @param delay when should this operation time out?
+ * @param delay when should this operation time out?
* @param wfd write file-descriptor
* @param task main function of the task
* @param task_cls closure of @a task
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready.
+ * Only allowed to be called as long as the scheduler is running, that
+ * is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param priority priority of the task
* (prerequisite-run)
* && (delay-ready
* || any-rs-ready
- * || any-ws-ready)
+ * || any-ws-ready) )
* </code>
+ * Only allowed to be called as long as the scheduler is running, that
+ * is one of the following conditions is met:
+ *
+ * - #GNUNET_SCHEDULER_run has been called and has not returned yet
+ * - #GNUNET_SCHEDULER_driver_init has been run and
+ * #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param prio how important is this task?
* @param delay how long should we wait?
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
- * only valid until "task" is started!
+ * only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio,