#include "gnunet_network_lib.h"
+/**
+ * Possible events on FDs, used as a bitmask.
+ * Modelled after GPollFD.
+ */
+enum GNUNET_SCHEDULER_EventType
+{
+
+ /**
+ * No event (useful for timeout).
+ */
+ GNUNET_SCHEDULER_ET_NONE = 0,
+
+ /**
+ * Data available for reading.
+ */
+ GNUNET_SCHEDULER_ET_IN = 1,
+
+ /**
+ * Buffer available for writing.
+ */
+ GNUNET_SCHEDULER_ET_OUT = 2,
+
+ /**
+ *
+ */
+ GNUNET_SCHEDULER_ET_HUP = 4,
+
+ /**
+ *
+ */
+ GNUNET_SCHEDULER_ET_ERR = 8,
+
+ /**
+ *
+ */
+ GNUNET_SCHEDULER_ET_PRI = 16,
+
+ /**
+ *
+ */
+ GNUNET_SCHEDULER_ET_NVAL = 32
+
+};
+
+
+/**
+ * Information about an event relating to a file descriptor/socket.
+ */
+struct GNUNET_SCHEDULER_FdInfo
+{
+
+ /**
+ * GNUnet network socket the event is about, matches @a sock,
+ * NULL if this is about a file handle or if no network
+ * handle was given to the scheduler originally.
+ */
+ struct GNUNET_NETWORK_Handle *fd;
+
+ /**
+ * GNUnet file handle the event is about, matches @a sock,
+ * NULL if this is about a network socket or if no network
+ * handle was given to the scheduler originally.
+ */
+ struct GNUNET_DISK_FileHandle *fh;
+
+ /**
+ * Type of the event that was generated related to @e sock.
+ */
+ enum GNUNET_SCHEDULER_EventType et;
+
+ /**
+ * Underlying OS handle the event was about.
+ */
+ int sock;
+
+};
+
+
/**
* Context information passed to each scheduler task.
*/
enum GNUNET_SCHEDULER_Reason reason;
/**
- * Set of file descriptors ready for reading;
- * note that additional bits may be set
- * that were not in the original request
+ * Length of the following array.
+ */
+ unsigned int fds_len;
+
+ /**
+ * Array of length @e fds_len with information about ready FDs.
+ * Note that we use the same format regardless of the internal
+ * event loop that was used. The given array should only contain
+ * information about file descriptors relevant to the current task.
+ */
+ const struct GNUNET_SCHEDULER_FdInfo *fds;
+
+ /**
+ * Set of file descriptors ready for reading; note that additional
+ * bits may be set that were not in the original request.
+ * @deprecated
*/
const struct GNUNET_NETWORK_FDSet *read_ready;
/**
- * Set of file descriptors ready for writing;
- * note that additional bits may be set
- * that were not in the original request.
+ * Set of file descriptors ready for writing; note that additional
+ * bits may be set that were not in the original request.
+ * @deprecated
*/
const struct GNUNET_NETWORK_FDSet *write_ready;
};
+/**
+ * Function used by event-loop implementations to signal the scheduler
+ * that a particular @a task is ready due to an event of type @a et.
+ *
+ * This function will then queue the task to notify the application
+ * that the task is ready (with the respective priority).
+ *
+ * @param task the task that is ready
+ * @param et information about why the task is ready
+ */
+void
+GNUNET_SCHEDULER_task_ready (struct GNUNET_SCHEDULER_Task *task,
+ enum GNUNET_SCHEDULER_EventType et);
+
+
+/**
+ * Handle to the scheduler's state to be used by the driver.
+ */
+struct GNUNET_SCHEDULER_Handle;
+
+
+/**
+ * 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 the operating system has more work as the
+ * scheduler has no more work to do right now.
+ *
+ * @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
+ */
+int
+GNUNET_SCHEDULER_run_from_driver (struct GNUNET_SCHEDULER_Handle *sh);
+
+
+/**
+ * API a driver has to implement for
+ * #GNUNET_SCHEDULER_run_with_driver().
+ */
+struct GNUNET_SCHEDULER_Driver
+{
+
+ /**
+ * Closure to pass to the functions in this struct.
+ */
+ void *cls;
+
+ /**
+ * Add a @a task to be run if the conditions given
+ * in @a fdi are satisfied.
+ *
+ * @param cls closure
+ * @param task task to add
+ * @param fdi conditions to watch for
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
+ * (i.e. @a fdi too high or invalid)
+ */
+ int
+ (*add)(void *cls,
+ struct GNUNET_SCHEDULER_Task *task,
+ struct GNUNET_SCHEDULER_FdInfo *fdi);
+
+ /**
+ * Delete a @a task from the set of tasks to be run.
+ *
+ * @param cls closure
+ * @param task task to delete
+ * @param fdi conditions to watch for (must match @e add call)
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
+ * (i.e. @a task or @a fdi do not match prior @e add call)
+ */
+ int
+ (*del)(void *cls,
+ struct GNUNET_SCHEDULER_Task *task,
+ const struct GNUNET_SCHEDULER_FdInfo *fdi);
+
+ /**
+ * Set time at which we definitively want to get a wakeup call.
+ *
+ * @param cls closure
+ * @param dt time when we want to wake up next
+ */
+ void
+ (*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.
+ *
+ * @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);
+
+};
+
+
/**
* Signature of the main function of a task.
*
* @param cls closure
- * @param tc context information (why was this task triggered now)
*/
typedef void
(*GNUNET_SCHEDULER_TaskCallback) (void *cls);
+/**
+ * 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.
+ *
+ * @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
+ */
+int
+GNUNET_SCHEDULER_run_with_driver (const struct GNUNET_SCHEDULER_Driver *driver,
+ GNUNET_SCHEDULER_TaskCallback task,
+ void *task_cls);
+
+
+/**
+ * Obtain the driver for using select() as the event loop.
+ *
+ * @return NULL on error
+ */
+const struct GNUNET_SCHEDULER_Driver *
+GNUNET_SCHEDULER_driver_select (void);
+
+
/**
* Signature of the select function used by the scheduler.
* #GNUNET_NETWORK_socket_select matches it.
* Sets the select function to use in the scheduler (scheduler_select).
*
* @param new_select new select function to use (NULL to reset to default)
- * @param new_select_cls closure for 'new_select'
+ * @param new_select_cls closure for @a new_select
*/
void
GNUNET_SCHEDULER_set_select (GNUNET_SCHEDULER_select new_select,
/*
This file is part of GNUnet
- Copyright (C) 2009-2016 GNUnet e.V.
+ Copyright (C) 2009-2017 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
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
-
/**
* @file util/scheduler.c
* @brief schedule computations using continuation passing style
#define DELAY_THRESHOLD GNUNET_TIME_UNIT_SECONDS
+/**
+ * Argument to be passed from the driver to
+ * #GNUNET_SCHEDULER_run_from_driver(). Contains the
+ * scheduler's internal state.
+ */
+struct GNUNET_SCHEDULER_Handle
+{
+ /**
+ * Passed here to avoid constantly allocating/deallocating
+ * this element, but generally we want to get rid of this.
+ * @deprecated
+ */
+ struct GNUNET_NETWORK_FDSet *rs;
+
+ /**
+ * Passed here to avoid constantly allocating/deallocating
+ * this element, but generally we want to get rid of this.
+ * @deprecated
+ */
+ struct GNUNET_NETWORK_FDSet *ws;
+
+ /**
+ * Driver we used for the event loop.
+ */
+ const struct GNUNET_SCHEDULER_Driver *driver;
+
+};
+
+
/**
* Entry in list of pending tasks.
*/
*/
void *callback_cls;
+ /**
+ * Handle to the scheduler's state.
+ */
+ const struct GNUNET_SCHEDULER_Handle *sh;
+
/**
* Set of file descriptors this task is waiting
* for for reading. Once ready, this is updated
*/
struct GNUNET_NETWORK_FDSet *write_set;
+ /**
+ * Information about which FDs are ready for this task (and why).
+ */
+ const struct GNUNET_SCHEDULER_FdInfo *fds;
+
+ /**
+ * Storage location used for @e fds if we want to avoid
+ * a separate malloc() call in the common case that this
+ * task is only about a single FD.
+ */
+ struct GNUNET_SCHEDULER_FdInfo fdx;
+
/**
* Absolute timeout value for the task, or
* #GNUNET_TIME_UNIT_FOREVER_ABS for "no timeout".
struct GNUNET_TIME_Absolute start_time;
#endif
+ /**
+ * Size of the @e fds array.
+ */
+ unsigned int fds_len;
+
/**
* Why is the task ready? Set after task is added to ready queue.
* Initially set to zero. All reasons that have already been
GNUNET_CONTAINER_DLL_insert (pending_head,
pending_tail,
t);
- max_priority_added = GNUNET_MAX (max_priority_added, t->priority);
+ max_priority_added = GNUNET_MAX (max_priority_added,
+ t->priority);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Adding task %p\n",
t);
return t;
}
+
+/**
+ * Function used by event-loop implementations to signal the scheduler
+ * that a particular @a task is ready due to an event of type @a et.
+ *
+ * This function will then queue the task to notify the application
+ * that the task is ready (with the respective priority).
+ *
+ * @param task the task that is ready, NULL for wake up calls
+ * @param et information about why the task is ready
+ */
+void
+GNUNET_SCHEDULER_task_ready (struct GNUNET_SCHEDULER_Task *task,
+ enum GNUNET_SCHEDULER_EventType et)
+{
+ enum GNUNET_SCHEDULER_Reason reason;
+ struct GNUNET_TIME_Absolute now;
+
+ now = GNUNET_TIME_absolute_get ();
+ reason = task->reason;
+ if (now.abs_value_us >= task->timeout.abs_value_us)
+ reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
+ if ( (0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
+ (0 != (GNUNET_SCHEDULER_ET_IN & et)) )
+ reason |= GNUNET_SCHEDULER_REASON_READ_READY;
+ if ( (0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
+ (0 != (GNUNET_SCHEDULER_ET_OUT & et)) )
+ reason |= GNUNET_SCHEDULER_REASON_WRITE_READY;
+ reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE;
+ task->reason = reason;
+ task->fds = &task->fdx;
+ task->fdx.et = et;
+ task->fds_len = 1;
+ queue_ready_task (task);
+}
+
+
+/**
+ * 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 the operating system has more work as the
+ * scheduler has no more work to do right now.
+ *
+ * @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
+ */
+int
+GNUNET_SCHEDULER_run_from_driver (struct GNUNET_SCHEDULER_Handle *sh)
+{
+ enum GNUNET_SCHEDULER_Priority p;
+ struct GNUNET_SCHEDULER_Task *pos;
+ struct GNUNET_TIME_Absolute now;
+
+ /* check for tasks that reached the timeout! */
+ now = GNUNET_TIME_absolute_get ();
+ while (NULL != (pos = pending_timeout_head))
+ {
+ if (now.abs_value_us >= pos->timeout.abs_value_us)
+ pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
+ if (0 == pos->reason)
+ break;
+ GNUNET_CONTAINER_DLL_remove (pending_timeout_head,
+ pending_timeout_tail,
+ pos);
+ if (pending_timeout_last == pos)
+ pending_timeout_last = NULL;
+ queue_ready_task (pos);
+ }
+
+ if (0 == ready_count)
+ return GNUNET_NO;
+
+ /* find out which task priority level we are going to
+ process this time */
+ max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
+ GNUNET_assert (NULL == ready_head[GNUNET_SCHEDULER_PRIORITY_KEEP]);
+ /* yes, p>0 is correct, 0 is "KEEP" which should
+ * always be an empty queue (see assertion)! */
+ for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)
+ {
+ pos = ready_head[p];
+ if (NULL != pos)
+ break;
+ }
+ GNUNET_assert (NULL != pos); /* ready_count wrong? */
+
+ /* process all tasks at this priority level, then yield */
+ while (NULL != (pos = ready_head[p]))
+ {
+ GNUNET_CONTAINER_DLL_remove (ready_head[p],
+ ready_tail[p],
+ pos);
+ ready_count--;
+ current_priority = pos->priority;
+ current_lifeness = pos->lifeness;
+ active_task = pos;
+#if PROFILE_DELAYS
+ if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value_us >
+ DELAY_THRESHOLD.rel_value_us)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Task %p took %s to be scheduled\n",
+ pos,
+ GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (pos->start_time),
+ GNUNET_YES));
+ }
+#endif
+ tc.reason = pos->reason;
+ GNUNET_NETWORK_fdset_zero (sh->rs);
+ GNUNET_NETWORK_fdset_zero (sh->ws);
+ tc.fds_len = pos->fds_len;
+ tc.fds = pos->fds;
+ tc.read_ready = (NULL == pos->read_set) ? sh->rs : pos->read_set;
+ if ( (-1 != pos->read_fd) &&
+ (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY)) )
+ GNUNET_NETWORK_fdset_set_native (sh->rs,
+ pos->read_fd);
+ tc.write_ready = (NULL == pos->write_set) ? sh->ws : pos->write_set;
+ if ((-1 != pos->write_fd) &&
+ (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)))
+ GNUNET_NETWORK_fdset_set_native (sh->ws,
+ pos->write_fd);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Running task: %p\n",
+ pos);
+ pos->callback (pos->callback_cls);
+ active_task = NULL;
+ dump_backtrace (pos);
+ destroy_task (pos);
+ tasks_run++;
+ }
+ if (0 == ready_count)
+ return GNUNET_NO;
+ return GNUNET_OK;
+}
+
+
+/**
+ * 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.
+ *
+ * @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
+ */
+int
+GNUNET_SCHEDULER_run_with_driver (const struct GNUNET_SCHEDULER_Driver *driver,
+ GNUNET_SCHEDULER_TaskCallback task,
+ void *task_cls)
+{
+ int ret;
+ struct GNUNET_SIGNAL_Context *shc_int;
+ struct GNUNET_SIGNAL_Context *shc_term;
+#if (SIGTERM != GNUNET_TERM_SIG)
+ struct GNUNET_SIGNAL_Context *shc_gterm;
+#endif
+#ifndef MINGW
+ struct GNUNET_SIGNAL_Context *shc_quit;
+ struct GNUNET_SIGNAL_Context *shc_hup;
+ struct GNUNET_SIGNAL_Context *shc_pipe;
+#endif
+ struct GNUNET_SCHEDULER_Task tsk;
+ const struct GNUNET_DISK_FileHandle *pr;
+ struct GNUNET_SCHEDULER_Handle sh;
+
+ /* general set-up */
+ GNUNET_assert (NULL == active_task);
+ GNUNET_assert (NULL == shutdown_pipe_handle);
+ shutdown_pipe_handle = GNUNET_DISK_pipe (GNUNET_NO,
+ GNUNET_NO,
+ GNUNET_NO,
+ GNUNET_NO);
+ GNUNET_assert (NULL != shutdown_pipe_handle);
+ pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle,
+ GNUNET_DISK_PIPE_END_READ);
+ GNUNET_assert (NULL != pr);
+ my_pid = getpid ();
+
+ /* install signal handlers */
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Registering signal handlers\n");
+ shc_int = GNUNET_SIGNAL_handler_install (SIGINT,
+ &sighandler_shutdown);
+ shc_term = GNUNET_SIGNAL_handler_install (SIGTERM,
+ &sighandler_shutdown);
+#if (SIGTERM != GNUNET_TERM_SIG)
+ shc_gterm = GNUNET_SIGNAL_handler_install (GNUNET_TERM_SIG,
+ &sighandler_shutdown);
+#endif
+#ifndef MINGW
+ shc_pipe = GNUNET_SIGNAL_handler_install (SIGPIPE,
+ &sighandler_pipe);
+ shc_quit = GNUNET_SIGNAL_handler_install (SIGQUIT,
+ &sighandler_shutdown);
+ shc_hup = GNUNET_SIGNAL_handler_install (SIGHUP,
+ &sighandler_shutdown);
+#endif
+
+ /* Setup initial tasks */
+ current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT;
+ current_lifeness = GNUNET_YES;
+ memset (&tsk,
+ 0,
+ sizeof (tsk));
+ active_task = &tsk;
+ tsk.sh = &sh;
+ GNUNET_SCHEDULER_add_with_reason_and_priority (task,
+ task_cls,
+ GNUNET_SCHEDULER_REASON_STARTUP,
+ GNUNET_SCHEDULER_PRIORITY_DEFAULT);
+ GNUNET_SCHEDULER_add_now_with_lifeness (GNUNET_NO,
+ &GNUNET_OS_install_parent_control_handler,
+ NULL);
+ active_task = NULL;
+ driver->set_wakeup (driver->cls,
+ GNUNET_TIME_absolute_get ());
+
+ /* begin main event loop */
+ sh.rs = GNUNET_NETWORK_fdset_create ();
+ sh.ws = GNUNET_NETWORK_fdset_create ();
+ sh.driver = driver;
+ ret = driver->loop (driver->cls,
+ &sh);
+ GNUNET_NETWORK_fdset_destroy (sh.rs);
+ GNUNET_NETWORK_fdset_destroy (sh.ws);
+
+ /* uninstall signal handlers */
+ GNUNET_SIGNAL_handler_uninstall (shc_int);
+ GNUNET_SIGNAL_handler_uninstall (shc_term);
+#if (SIGTERM != GNUNET_TERM_SIG)
+ GNUNET_SIGNAL_handler_uninstall (shc_gterm);
+#endif
+#ifndef MINGW
+ GNUNET_SIGNAL_handler_uninstall (shc_pipe);
+ GNUNET_SIGNAL_handler_uninstall (shc_quit);
+ GNUNET_SIGNAL_handler_uninstall (shc_hup);
+#endif
+ GNUNET_DISK_pipe_close (shutdown_pipe_handle);
+ shutdown_pipe_handle = NULL;
+ return ret;
+}
+
+
+/**
+ * Obtain the driver for using select() as the event loop.
+ *
+ * @return NULL on error
+ */
+const struct GNUNET_SCHEDULER_Driver *
+GNUNET_SCHEDULER_driver_select ()
+{
+ GNUNET_break (0); // not implemented
+ return NULL;
+}
+
+
/* end of scheduler.c */
projects / oweals / gnunet.git / commitdiff