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21 * @file util/scheduler.c
22 * @brief schedule computations using continuation passing style
23 * @author Christian Grothoff
26 #include "gnunet_util_lib.h"
29 #define LOG(kind,...) GNUNET_log_from (kind, "util-scheduler", __VA_ARGS__)
31 #define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util-scheduler", syscall)
38 * Use lsof to generate file descriptor reports on select error?
39 * (turn off for stable releases).
41 #define USE_LSOF GNUNET_NO
44 * Obtain trace information for all scheduler calls that schedule tasks.
46 #define EXECINFO GNUNET_NO
49 * Check each file descriptor before adding
51 #define DEBUG_FDS GNUNET_NO
54 * Depth of the traces collected via EXECINFO.
56 #define MAX_TRACE_DEPTH 50
60 * Should we figure out which tasks are delayed for a while
61 * before they are run? (Consider using in combination with EXECINFO).
63 #define PROFILE_DELAYS GNUNET_NO
66 * Task that were in the queue for longer than this are reported if
67 * PROFILE_DELAYS is active.
69 #define DELAY_THRESHOLD GNUNET_TIME_UNIT_SECONDS
73 * Argument to be passed from the driver to
74 * #GNUNET_SCHEDULER_run_from_driver(). Contains the
75 * scheduler's internal state.
77 struct GNUNET_SCHEDULER_Handle
80 * Passed here to avoid constantly allocating/deallocating
81 * this element, but generally we want to get rid of this.
84 struct GNUNET_NETWORK_FDSet *rs;
87 * Passed here to avoid constantly allocating/deallocating
88 * this element, but generally we want to get rid of this.
91 struct GNUNET_NETWORK_FDSet *ws;
94 * Driver we used for the event loop.
96 const struct GNUNET_SCHEDULER_Driver *driver;
102 * Entry in list of pending tasks.
104 struct GNUNET_SCHEDULER_Task
107 * This is a linked list.
109 struct GNUNET_SCHEDULER_Task *next;
112 * This is a linked list.
114 struct GNUNET_SCHEDULER_Task *prev;
117 * Function to run when ready.
119 GNUNET_SCHEDULER_TaskCallback callback;
122 * Closure for the @e callback.
127 * Handle to the scheduler's state.
129 const struct GNUNET_SCHEDULER_Handle *sh;
132 * Set of file descriptors this task is waiting
133 * for for reading. Once ready, this is updated
134 * to reflect the set of file descriptors ready
137 struct GNUNET_NETWORK_FDSet *read_set;
140 * Set of file descriptors this task is waiting for for writing.
141 * Once ready, this is updated to reflect the set of file
142 * descriptors ready for operation.
144 struct GNUNET_NETWORK_FDSet *write_set;
147 * Information about which FDs are ready for this task (and why).
149 const struct GNUNET_SCHEDULER_FdInfo *fds;
152 * Storage location used for @e fds if we want to avoid
153 * a separate malloc() call in the common case that this
154 * task is only about a single FD.
156 struct GNUNET_SCHEDULER_FdInfo fdx;
159 * Absolute timeout value for the task, or
160 * #GNUNET_TIME_UNIT_FOREVER_ABS for "no timeout".
162 struct GNUNET_TIME_Absolute timeout;
166 * When was the task scheduled?
168 struct GNUNET_TIME_Absolute start_time;
172 * Size of the @e fds array.
174 unsigned int fds_len;
177 * Why is the task ready? Set after task is added to ready queue.
178 * Initially set to zero. All reasons that have already been
179 * satisfied (i.e. read or write ready) will be set over time.
181 enum GNUNET_SCHEDULER_Reason reason;
186 enum GNUNET_SCHEDULER_Priority priority;
189 * Set if we only wait for reading from a single FD, otherwise -1.
194 * Set if we only wait for writing to a single FD, otherwise -1.
199 * Should the existence of this task in the queue be counted as
200 * reason to not shutdown the scheduler?
205 * Is this task run on shutdown?
210 * Is this task in the ready list?
216 * Array of strings which make up a backtrace from the point when this
217 * task was scheduled (essentially, who scheduled the task?)
219 char **backtrace_strings;
222 * Size of the backtrace_strings array
224 int num_backtrace_strings;
231 * The driver used for the event loop. Will be handed over to
232 * the scheduler in #GNUNET_SCHEDULER_run_from_driver(), peristed
233 * there in this variable for later use in functions like
234 * #GNUNET_SCHEDULER_add_select(), #add_without_sets() and
235 * #GNUNET_SCHEDULER_cancel().
237 static const struct GNUNET_SCHEDULER_Driver *scheduler_driver;
240 * Head of list of tasks waiting for an event.
242 static struct GNUNET_SCHEDULER_Task *pending_head;
245 * Tail of list of tasks waiting for an event.
247 static struct GNUNET_SCHEDULER_Task *pending_tail;
250 * Head of list of tasks waiting for shutdown.
252 static struct GNUNET_SCHEDULER_Task *shutdown_head;
255 * Tail of list of tasks waiting for shutdown.
257 static struct GNUNET_SCHEDULER_Task *shutdown_tail;
260 * List of tasks waiting ONLY for a timeout event.
261 * Sorted by timeout (earliest first). Used so that
262 * we do not traverse the list of these tasks when
263 * building select sets (we just look at the head
264 * to determine the respective timeout ONCE).
266 static struct GNUNET_SCHEDULER_Task *pending_timeout_head;
269 * List of tasks waiting ONLY for a timeout event.
270 * Sorted by timeout (earliest first). Used so that
271 * we do not traverse the list of these tasks when
272 * building select sets (we just look at the head
273 * to determine the respective timeout ONCE).
275 static struct GNUNET_SCHEDULER_Task *pending_timeout_tail;
278 * Last inserted task waiting ONLY for a timeout event.
279 * Used to (heuristically) speed up insertion.
281 static struct GNUNET_SCHEDULER_Task *pending_timeout_last;
284 * ID of the task that is running right now.
286 static struct GNUNET_SCHEDULER_Task *active_task;
289 * Head of list of tasks ready to run right now, grouped by importance.
291 static struct GNUNET_SCHEDULER_Task *ready_head[GNUNET_SCHEDULER_PRIORITY_COUNT];
294 * Tail of list of tasks ready to run right now, grouped by importance.
296 static struct GNUNET_SCHEDULER_Task *ready_tail[GNUNET_SCHEDULER_PRIORITY_COUNT];
299 * Number of tasks on the ready list.
301 static unsigned int ready_count;
304 * How many tasks have we run so far?
306 static unsigned long long tasks_run;
309 * Priority of the task running right now. Only
310 * valid while a task is running.
312 static enum GNUNET_SCHEDULER_Priority current_priority;
315 * Priority of the highest task added in the current select
318 static enum GNUNET_SCHEDULER_Priority max_priority_added;
321 * Value of the 'lifeness' flag for the current task.
323 static int current_lifeness;
326 * Function to use as a select() in the scheduler.
327 * If NULL, we use GNUNET_NETWORK_socket_select().
329 static GNUNET_SCHEDULER_select scheduler_select;
332 * Task context of the current task.
334 static struct GNUNET_SCHEDULER_TaskContext tc;
337 * Closure for #scheduler_select.
339 static void *scheduler_select_cls;
343 * Sets the select function to use in the scheduler (scheduler_select).
345 * @param new_select new select function to use
346 * @param new_select_cls closure for @a new_select
347 * @return previously used select function, NULL for default
350 GNUNET_SCHEDULER_set_select (GNUNET_SCHEDULER_select new_select,
351 void *new_select_cls)
353 scheduler_select = new_select;
354 scheduler_select_cls = new_select_cls;
359 * Check that the given priority is legal (and return it).
361 * @param p priority value to check
362 * @return p on success, 0 on error
364 static enum GNUNET_SCHEDULER_Priority
365 check_priority (enum GNUNET_SCHEDULER_Priority p)
367 if ((p >= 0) && (p < GNUNET_SCHEDULER_PRIORITY_COUNT))
370 return 0; /* make compiler happy */
375 * Update all sets and timeout for select.
377 * @param rs read-set, set to all FDs we would like to read (updated)
378 * @param ws write-set, set to all FDs we would like to write (updated)
379 * @param timeout next timeout (updated)
381 void getNextPendingTimeout(struct GNUNET_TIME_Relative *timeout)
384 struct GNUNET_SCHEDULER_Task *pos;
385 struct GNUNET_TIME_Absolute now;
386 struct GNUNET_TIME_Relative to;
388 now = GNUNET_TIME_absolute_get ();
389 pos = pending_timeout_head;
392 to = GNUNET_TIME_absolute_get_difference (now, pos->timeout);
393 if (timeout->rel_value_us > to.rel_value_us)
395 if (0 != pos->reason)
396 *timeout = GNUNET_TIME_UNIT_ZERO;
401 update_sets (struct GNUNET_NETWORK_FDSet *rs,
402 struct GNUNET_NETWORK_FDSet *ws,
403 struct GNUNET_TIME_Relative *timeout)
405 struct GNUNET_SCHEDULER_Task *pos;
406 struct GNUNET_TIME_Absolute now;
407 struct GNUNET_TIME_Relative to;
409 now = GNUNET_TIME_absolute_get ();
411 getNextPendingTimeout(timeout);
412 for (pos = pending_head; NULL != pos; pos = pos->next)
414 if (pos->timeout.abs_value_us != GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us)
416 to = GNUNET_TIME_absolute_get_difference (now, pos->timeout);
417 if (timeout->rel_value_us > to.rel_value_us)
420 if (-1 != pos->read_fd)
421 GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd);
422 if (-1 != pos->write_fd)
423 GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd);
424 if (NULL != pos->read_set)
425 GNUNET_NETWORK_fdset_add (rs, pos->read_set);
426 if (NULL != pos->write_set)
427 GNUNET_NETWORK_fdset_add (ws, pos->write_set);
428 if (0 != pos->reason)
429 *timeout = GNUNET_TIME_UNIT_ZERO;
435 * Check if the ready set overlaps with the set we want to have ready.
436 * If so, update the want set (set all FDs that are ready). If not,
439 * @param ready set that is ready
440 * @param want set that we want to be ready
441 * @return #GNUNET_YES if there was some overlap
444 set_overlaps (const struct GNUNET_NETWORK_FDSet *ready,
445 struct GNUNET_NETWORK_FDSet *want)
447 if ((NULL == want) || (NULL == ready))
449 if (GNUNET_NETWORK_fdset_overlap (ready, want))
451 /* copy all over (yes, there maybe unrelated bits,
452 * but this should not hurt well-written clients) */
453 GNUNET_NETWORK_fdset_copy (want, ready);
461 * Check if the given task is eligible to run now.
462 * Also set the reason why it is eligible.
464 * @param task task to check if it is ready
465 * @param now the current time
466 * @param rs set of FDs ready for reading
467 * @param ws set of FDs ready for writing
468 * @return #GNUNET_YES if we can run it, #GNUNET_NO if not.
471 is_ready (struct GNUNET_SCHEDULER_Task *task,
472 struct GNUNET_TIME_Absolute now,
473 const struct GNUNET_NETWORK_FDSet *rs,
474 const struct GNUNET_NETWORK_FDSet *ws)
476 enum GNUNET_SCHEDULER_Reason reason;
478 reason = task->reason;
479 if (now.abs_value_us >= task->timeout.abs_value_us)
480 reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
481 if ((0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
482 (((task->read_fd != -1) &&
483 (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (rs, task->read_fd))) ||
484 (set_overlaps (rs, task->read_set))))
485 reason |= GNUNET_SCHEDULER_REASON_READ_READY;
486 if ((0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
487 (((task->write_fd != -1) &&
488 (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (ws, task->write_fd)))
489 || (set_overlaps (ws, task->write_set))))
490 reason |= GNUNET_SCHEDULER_REASON_WRITE_READY;
492 return GNUNET_NO; /* not ready */
493 reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE;
494 task->reason = reason;
500 * Put a task that is ready for execution into the ready queue.
502 * @param task task ready for execution
505 queue_ready_task (struct GNUNET_SCHEDULER_Task *task)
507 enum GNUNET_SCHEDULER_Priority p = check_priority (task->priority);
509 GNUNET_CONTAINER_DLL_insert (ready_head[p],
512 task->in_ready_list = GNUNET_YES;
518 * Check which tasks are ready and move them
519 * to the respective ready queue.
521 * @param rs FDs ready for reading
522 * @param ws FDs ready for writing
525 check_ready (const struct GNUNET_NETWORK_FDSet *rs,
526 const struct GNUNET_NETWORK_FDSet *ws)
528 struct GNUNET_SCHEDULER_Task *pos;
529 struct GNUNET_SCHEDULER_Task *next;
530 struct GNUNET_TIME_Absolute now;
532 now = GNUNET_TIME_absolute_get ();
533 while (NULL != (pos = pending_timeout_head))
535 if (now.abs_value_us >= pos->timeout.abs_value_us)
536 pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
537 if (0 == pos->reason)
539 scheduler_driver->set_wakeup (scheduler_driver->cls,
540 pending_timeout_head->timeout);
541 GNUNET_CONTAINER_DLL_remove (pending_timeout_head,
542 pending_timeout_tail,
544 if (pending_timeout_last == pos)
545 pending_timeout_last = NULL;
546 queue_ready_task (pos);
552 if (GNUNET_YES == is_ready (pos, now, rs, ws))
554 GNUNET_CONTAINER_DLL_remove (pending_head,
557 queue_ready_task (pos);
565 * Request the shutdown of a scheduler. Marks all tasks
566 * awaiting shutdown as ready. Note that tasks
567 * scheduled with #GNUNET_SCHEDULER_add_shutdown() AFTER this call
568 * will be delayed until the next shutdown signal.
571 GNUNET_SCHEDULER_shutdown ()
573 struct GNUNET_SCHEDULER_Task *pos;
575 while (NULL != (pos = shutdown_head))
577 GNUNET_CONTAINER_DLL_remove (shutdown_head,
580 pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
581 queue_ready_task (pos);
587 * Destroy a task (release associated resources)
589 * @param t task to destroy
592 destroy_task (struct GNUNET_SCHEDULER_Task *t)
594 if (NULL != t->read_set)
595 GNUNET_NETWORK_fdset_destroy (t->read_set);
596 if (NULL != t->write_set)
597 GNUNET_NETWORK_fdset_destroy (t->write_set);
599 GNUNET_free (t->backtrace_strings);
606 * Output stack trace of task @a t.
608 * @param t task to dump stack trace of
611 dump_backtrace (struct GNUNET_SCHEDULER_Task *t)
616 for (i = 0; i < t->num_backtrace_strings; i++)
617 LOG (GNUNET_ERROR_TYPE_DEBUG,
618 "Task %p trace %u: %s\n",
621 t->backtrace_strings[i]);
627 * Run at least one task in the highest-priority queue that is not
628 * empty. Keep running tasks until we are either no longer running
629 * "URGENT" tasks or until we have at least one "pending" task (which
630 * may become ready, hence we should select on it). Naturally, if
631 * there are no more ready tasks, we also return.
633 * @param rs FDs ready for reading
634 * @param ws FDs ready for writing
637 run_ready (struct GNUNET_NETWORK_FDSet *rs,
638 struct GNUNET_NETWORK_FDSet *ws)
640 enum GNUNET_SCHEDULER_Priority p;
641 struct GNUNET_SCHEDULER_Task *pos;
643 max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
646 if (0 == ready_count)
648 GNUNET_assert (NULL == ready_head[GNUNET_SCHEDULER_PRIORITY_KEEP]);
649 /* yes, p>0 is correct, 0 is "KEEP" which should
650 * always be an empty queue (see assertion)! */
651 for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)
657 GNUNET_assert (NULL != pos); /* ready_count wrong? */
658 GNUNET_CONTAINER_DLL_remove (ready_head[p],
662 current_priority = pos->priority;
663 current_lifeness = pos->lifeness;
666 if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value_us >
667 DELAY_THRESHOLD.rel_value_us)
669 LOG (GNUNET_ERROR_TYPE_DEBUG,
670 "Task %p took %s to be scheduled\n",
672 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (pos->start_time),
676 tc.reason = pos->reason;
677 tc.read_ready = (NULL == pos->read_set) ? rs : pos->read_set;
678 if ((-1 != pos->read_fd) &&
679 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY)))
680 GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd);
681 tc.write_ready = (NULL == pos->write_set) ? ws : pos->write_set;
682 if ((-1 != pos->write_fd) &&
683 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)))
684 GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd);
685 if ((0 != (tc.reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
686 (-1 != pos->write_fd) &&
687 (!GNUNET_NETWORK_fdset_test_native (ws, pos->write_fd)))
688 GNUNET_assert (0); // added to ready in previous select loop!
689 LOG (GNUNET_ERROR_TYPE_DEBUG,
690 "Running task: %p\n",
692 pos->callback (pos->callback_cls);
693 dump_backtrace (pos);
698 while ((NULL == pending_head) || (p >= max_priority_added));
703 * Pipe used to communicate shutdown via signal.
705 static struct GNUNET_DISK_PipeHandle *shutdown_pipe_handle;
708 * Process ID of this process at the time we installed the various
714 * Signal handler called for SIGPIPE.
726 * Wait for a short time.
727 * Sleeps for @a ms ms (as that should be long enough for virtually all
728 * modern systems to context switch and allow another process to do
731 * @param ms how many ms to wait
734 short_wait (unsigned int ms)
736 struct GNUNET_TIME_Relative timeout;
738 timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, ms);
739 (void) GNUNET_NETWORK_socket_select (NULL, NULL, NULL, timeout);
744 * Signal handler called for signals that should cause us to shutdown.
747 sighandler_shutdown ()
750 int old_errno = errno; /* backup errno */
752 if (getpid () != my_pid)
753 exit (1); /* we have fork'ed since the signal handler was created,
754 * ignore the signal, see https://gnunet.org/vfork discussion */
755 GNUNET_DISK_file_write (GNUNET_DISK_pipe_handle
756 (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_WRITE),
763 * Check if the system is still alive. Trigger shutdown if we
764 * have tasks, but none of them give us lifeness.
766 * @return #GNUNET_OK to continue the main loop,
772 struct GNUNET_SCHEDULER_Task *t;
776 for (t = pending_head; NULL != t; t = t->next)
777 if (t->lifeness == GNUNET_YES)
779 for (t = shutdown_head; NULL != t; t = t->next)
780 if (t->lifeness == GNUNET_YES)
782 for (t = pending_timeout_head; NULL != t; t = t->next)
783 if (t->lifeness == GNUNET_YES)
785 if (NULL != shutdown_head)
787 GNUNET_SCHEDULER_shutdown ();
795 int while_live(struct GNUNET_NETWORK_FDSet *rs, struct GNUNET_NETWORK_FDSet *ws)
798 unsigned int busy_wait_warning;
799 unsigned long long last_tr;
800 const struct GNUNET_DISK_FileHandle *pr;
802 struct GNUNET_TIME_Relative timeout;
804 busy_wait_warning = 0;
805 pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle,
806 GNUNET_DISK_PIPE_END_READ);
807 GNUNET_assert (NULL != pr);
810 while (GNUNET_OK == check_lifeness ())
812 GNUNET_NETWORK_fdset_zero (rs);
813 GNUNET_NETWORK_fdset_zero (ws);
814 timeout = GNUNET_TIME_UNIT_FOREVER_REL;
815 update_sets (rs, ws, &timeout);
816 GNUNET_NETWORK_fdset_handle_set (rs, pr);
819 /* no blocking, more work already ready! */
820 timeout = GNUNET_TIME_UNIT_ZERO;
822 if (NULL == scheduler_select)
823 ret = GNUNET_NETWORK_socket_select (rs,
828 ret = scheduler_select (scheduler_select_cls,
833 if (ret == GNUNET_SYSERR)
838 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "select");
843 snprintf (lsof, sizeof (lsof), "lsof -p %d", getpid ());
846 if (0 != system (lsof))
847 LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING,
852 struct GNUNET_SCHEDULER_Task *t;
854 for (t = pending_head; NULL != t; t = t->next)
856 if (-1 != t->read_fd)
858 int flags = fcntl (t->read_fd, F_GETFD);
859 if ((flags == -1) && (errno == EBADF))
861 LOG (GNUNET_ERROR_TYPE_ERROR,
862 "Got invalid file descriptor %d!\n",
867 if (-1 != t->write_fd)
869 int flags = fcntl (t->write_fd, F_GETFD);
870 if ((flags == -1) && (errno == EBADF))
872 LOG (GNUNET_ERROR_TYPE_ERROR,
873 "Got invalid file descriptor %d!\n",
885 (0 == timeout.rel_value_us) &&
886 (busy_wait_warning > 16) )
888 LOG (GNUNET_ERROR_TYPE_WARNING,
889 "Looks like we're busy waiting...\n");
890 short_wait (100); /* mitigate */
892 check_ready (rs, ws);
894 if (GNUNET_NETWORK_fdset_handle_isset (rs, pr))
896 /* consume the signal */
897 GNUNET_DISK_file_read (pr, &c, sizeof (c));
898 /* mark all active tasks as ready due to shutdown */
899 GNUNET_SCHEDULER_shutdown ();
901 if (last_tr == tasks_run)
909 busy_wait_warning = 0;
916 * Initialize and run scheduler. This function will return when all
917 * tasks have completed. On systems with signals, receiving a SIGTERM
918 * (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown()
919 * to be run after the active task is complete. As a result, SIGTERM
920 * causes all active tasks to be scheduled with reason
921 * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added
922 * afterwards will execute normally!). Note that any particular signal
923 * will only shut down one scheduler; applications should always only
924 * create a single scheduler.
926 * @param task task to run immediately
927 * @param task_cls closure of @a task
930 GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_TaskCallback task,
934 GNUNET_SCHEDULER_run_with_driver(GNUNET_SCHEDULER_driver_select (), task, task_cls);
940 * Obtain the task context, giving the reason why the current task was
943 * @return current tasks' scheduler context
945 const struct GNUNET_SCHEDULER_TaskContext *
946 GNUNET_SCHEDULER_get_task_context ()
948 GNUNET_assert (NULL != active_task);
954 * Get information about the current load of this scheduler. Use this
955 * function to determine if an elective task should be added or simply
956 * dropped (if the decision should be made based on the number of
957 * tasks ready to run).
959 * @param p priority level to look at
960 * @return number of tasks pending right now
963 GNUNET_SCHEDULER_get_load (enum GNUNET_SCHEDULER_Priority p)
965 struct GNUNET_SCHEDULER_Task *pos;
968 GNUNET_assert (NULL != active_task);
969 if (p == GNUNET_SCHEDULER_PRIORITY_COUNT)
971 if (p == GNUNET_SCHEDULER_PRIORITY_KEEP)
972 p = current_priority;
974 for (pos = ready_head[check_priority (p)]; NULL != pos; pos = pos->next)
981 initFdInfo(struct GNUNET_SCHEDULER_Task *t,
982 const struct GNUNET_NETWORK_Handle *read_nh,
983 const struct GNUNET_NETWORK_Handle *write_nh,
984 const struct GNUNET_DISK_FileHandle *read_fh,
985 const struct GNUNET_DISK_FileHandle *write_fh)
987 // either only network handles or only file handles are allowed
988 GNUNET_assert (!((NULL != read_nh || NULL != write_nh) && (NULL != read_fh || NULL != write_fh)));
990 if (NULL != read_nh && NULL != write_nh)
993 t->fds = GNUNET_new_array (2, struct GNUNET_SCHEDULER_FdInfo);
994 const struct GNUNET_SCHEDULER_FdInfo read_fdi = { .fd = read_nh, .et = GNUNET_SCHEDULER_ET_IN, .sock = GNUNET_NETWORK_get_fd (read_nh)};
995 const struct GNUNET_SCHEDULER_FdInfo write_fdi = { .fd = write_nh, .et = GNUNET_SCHEDULER_ET_OUT, .sock = GNUNET_NETWORK_get_fd (write_nh)};
997 const struct GNUNET_SCHEDULER_FdInfo array[2] = {read_fdi, write_fdi};
1000 else if (NULL != read_fh && NULL != write_fh)
1003 t->fds = GNUNET_new_array (2, struct GNUNET_SCHEDULER_FdInfo);
1004 const struct GNUNET_SCHEDULER_FdInfo read_fdi = { .fh = read_fh, .et = GNUNET_SCHEDULER_ET_IN};
1005 const struct GNUNET_SCHEDULER_FdInfo write_fdi = { .fh = write_fh, .et = GNUNET_SCHEDULER_ET_OUT, .sock = GNUNET_NETWORK_get_fd (write_nh)};
1006 const struct GNUNET_SCHEDULER_FdInfo array[2] = {read_fdi, write_fdi};
1009 else if (NULL != read_nh)
1011 struct GNUNET_SCHEDULER_FdInfo read_fdi = { .fd = read_nh, .et = GNUNET_SCHEDULER_ET_IN, .sock = GNUNET_NETWORK_get_fd (read_nh)};
1014 else if (NULL != write_nh)
1016 struct GNUNET_SCHEDULER_FdInfo write_fdi = { .fd = write_nh, .et = GNUNET_SCHEDULER_ET_OUT, .sock = GNUNET_NETWORK_get_fd (write_nh)};
1019 else if (NULL != read_fh)
1021 struct GNUNET_SCHEDULER_FdInfo read_fdi = { .fh = read_fh, .et = GNUNET_SCHEDULER_ET_IN, .sock = read_fh->fd};
1024 else if (NULL != write_fh)
1026 struct GNUNET_SCHEDULER_FdInfo write_fdi = { .fh = write_fh, .et = GNUNET_SCHEDULER_ET_OUT, .sock = write_fh->fd};
1032 int scheduler_multi_function_call(struct GNUNET_SCHEDULER_Task *t, int (*driver_func)())
1034 if (t->fds_len > 1){
1035 int success = GNUNET_YES;
1036 for (int i = 0; i < t->fds_len;i++){
1037 success = driver_func(scheduler_driver->cls, t , t->fds+i) && success;
1041 return driver_func(scheduler_driver->cls, t , t->fds);
1047 * Cancel the task with the specified identifier.
1048 * The task must not yet have run.
1050 * @param task id of the task to cancel
1051 * @return original closure of the task
1054 GNUNET_SCHEDULER_cancel (struct GNUNET_SCHEDULER_Task *task)
1056 enum GNUNET_SCHEDULER_Priority p;
1059 GNUNET_assert ( (NULL != active_task) ||
1060 (GNUNET_NO == task->lifeness) );
1061 if (! task->in_ready_list)
1063 if ( (-1 == task->read_fd) &&
1064 (-1 == task->write_fd) &&
1065 (NULL == task->read_set) &&
1066 (NULL == task->write_set) )
1068 if (GNUNET_YES == task->on_shutdown)
1069 GNUNET_CONTAINER_DLL_remove (shutdown_head,
1074 GNUNET_CONTAINER_DLL_remove (pending_timeout_head,
1075 pending_timeout_tail,
1077 if (pending_timeout_last == task)
1078 pending_timeout_last = NULL;
1080 scheduler_driver->set_wakeup (scheduler_driver->cls,
1081 pending_timeout_head->timeout);
1083 if (task == pending_timeout_last)
1084 pending_timeout_last = NULL;
1088 GNUNET_CONTAINER_DLL_remove (pending_head,
1091 scheduler_multi_function_call(task, scheduler_driver->del);
1096 p = check_priority (task->priority);
1097 GNUNET_CONTAINER_DLL_remove (ready_head[p],
1102 ret = task->callback_cls;
1103 LOG (GNUNET_ERROR_TYPE_DEBUG,
1104 "Canceling task %p\n",
1106 destroy_task (task);
1112 * Initialize backtrace data for task @a t
1114 * @param t task to initialize
1117 init_backtrace (struct GNUNET_SCHEDULER_Task *t)
1120 void *backtrace_array[MAX_TRACE_DEPTH];
1122 t->num_backtrace_strings
1123 = backtrace (backtrace_array, MAX_TRACE_DEPTH);
1124 t->backtrace_strings =
1125 backtrace_symbols (backtrace_array,
1126 t->num_backtrace_strings);
1133 * Continue the current execution with the given function. This is
1134 * similar to the other "add" functions except that there is no delay
1135 * and the reason code can be specified.
1137 * @param task main function of the task
1138 * @param task_cls closure for @a task
1139 * @param reason reason for task invocation
1140 * @param priority priority to use for the task
1143 GNUNET_SCHEDULER_add_with_reason_and_priority (GNUNET_SCHEDULER_TaskCallback task,
1145 enum GNUNET_SCHEDULER_Reason reason,
1146 enum GNUNET_SCHEDULER_Priority priority)
1148 struct GNUNET_SCHEDULER_Task *t;
1150 GNUNET_assert (NULL != task);
1151 GNUNET_assert ((NULL != active_task) ||
1152 (GNUNET_SCHEDULER_REASON_STARTUP == reason));
1153 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1157 t->callback_cls = task_cls;
1159 t->start_time = GNUNET_TIME_absolute_get ();
1162 t->priority = priority;
1163 t->lifeness = current_lifeness;
1164 LOG (GNUNET_ERROR_TYPE_DEBUG,
1165 "Adding continuation task %p\n",
1168 queue_ready_task (t);
1173 * Schedule a new task to be run at the specified time. The task
1174 * will be scheduled for execution at time @a at.
1176 * @param at time when the operation should run
1177 * @param priority priority to use for the task
1178 * @param task main function of the task
1179 * @param task_cls closure of @a task
1180 * @return unique task identifier for the job
1181 * only valid until @a task is started!
1183 struct GNUNET_SCHEDULER_Task *
1184 GNUNET_SCHEDULER_add_at_with_priority (struct GNUNET_TIME_Absolute at,
1185 enum GNUNET_SCHEDULER_Priority priority,
1186 GNUNET_SCHEDULER_TaskCallback task,
1189 struct GNUNET_SCHEDULER_Task *t;
1190 struct GNUNET_SCHEDULER_Task *pos;
1191 struct GNUNET_SCHEDULER_Task *prev;
1193 GNUNET_assert (NULL != active_task);
1194 GNUNET_assert (NULL != task);
1195 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1197 t->callback_cls = task_cls;
1201 t->start_time = GNUNET_TIME_absolute_get ();
1204 t->priority = priority;
1205 t->lifeness = current_lifeness;
1206 /* try tail first (optimization in case we are
1207 * appending to a long list of tasks with timeouts) */
1208 if ( (NULL == pending_timeout_head) ||
1209 (at.abs_value_us < pending_timeout_head->timeout.abs_value_us) )
1211 GNUNET_CONTAINER_DLL_insert (pending_timeout_head,
1212 pending_timeout_tail,
1214 scheduler_driver->set_wakeup(scheduler_driver->cls,pending_timeout_head->timeout);
1218 /* first move from heuristic start backwards to before start time */
1219 prev = pending_timeout_last;
1220 while ( (NULL != prev) &&
1221 (prev->timeout.abs_value_us > t->timeout.abs_value_us) )
1223 /* now, move from heuristic start (or head of list) forward to insertion point */
1225 pos = pending_timeout_head;
1228 while ( (NULL != pos) &&
1229 ( (pos->timeout.abs_value_us <= t->timeout.abs_value_us) ||
1230 (0 != pos->reason) ) )
1235 GNUNET_CONTAINER_DLL_insert_after (pending_timeout_head,
1236 pending_timeout_tail,
1240 /* finally, update heuristic insertion point to last insertion... */
1241 pending_timeout_last = t;
1243 LOG (GNUNET_ERROR_TYPE_DEBUG,
1244 "Adding task: %p\n",
1252 * Schedule a new task to be run with a specified delay. The task
1253 * will be scheduled for execution once the delay has expired.
1255 * @param delay when should this operation time out?
1256 * @param priority priority to use for the task
1257 * @param task main function of the task
1258 * @param task_cls closure of @a task
1259 * @return unique task identifier for the job
1260 * only valid until @a task is started!
1262 struct GNUNET_SCHEDULER_Task *
1263 GNUNET_SCHEDULER_add_delayed_with_priority (struct GNUNET_TIME_Relative delay,
1264 enum GNUNET_SCHEDULER_Priority priority,
1265 GNUNET_SCHEDULER_TaskCallback task,
1268 return GNUNET_SCHEDULER_add_at_with_priority (GNUNET_TIME_relative_to_absolute (delay),
1276 * Schedule a new task to be run with a specified priority.
1278 * @param prio how important is the new task?
1279 * @param task main function of the task
1280 * @param task_cls closure of @a task
1281 * @return unique task identifier for the job
1282 * only valid until @a task is started!
1284 struct GNUNET_SCHEDULER_Task *
1285 GNUNET_SCHEDULER_add_with_priority (enum GNUNET_SCHEDULER_Priority prio,
1286 GNUNET_SCHEDULER_TaskCallback task,
1289 return GNUNET_SCHEDULER_add_delayed_with_priority (GNUNET_TIME_UNIT_ZERO,
1297 * Schedule a new task to be run at the specified time. The task
1298 * will be scheduled for execution once specified time has been
1299 * reached. It will be run with the DEFAULT priority.
1301 * @param at time at which this operation should run
1302 * @param task main function of the task
1303 * @param task_cls closure of @a task
1304 * @return unique task identifier for the job
1305 * only valid until @a task is started!
1307 struct GNUNET_SCHEDULER_Task *
1308 GNUNET_SCHEDULER_add_at (struct GNUNET_TIME_Absolute at,
1309 GNUNET_SCHEDULER_TaskCallback task,
1312 return GNUNET_SCHEDULER_add_at_with_priority (at,
1313 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1320 * Schedule a new task to be run with a specified delay. The task
1321 * will be scheduled for execution once the delay has expired. It
1322 * will be run with the DEFAULT priority.
1324 * @param delay when should this operation time out?
1325 * @param task main function of the task
1326 * @param task_cls closure of @a task
1327 * @return unique task identifier for the job
1328 * only valid until @a task is started!
1330 struct GNUNET_SCHEDULER_Task *
1331 GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay,
1332 GNUNET_SCHEDULER_TaskCallback task,
1335 return GNUNET_SCHEDULER_add_delayed_with_priority (delay,
1336 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1343 * Schedule a new task to be run as soon as possible. Note that this
1344 * does not guarantee that this will be the next task that is being
1345 * run, as other tasks with higher priority (or that are already ready
1346 * to run) might get to run first. Just as with delays, clients must
1347 * not rely on any particular order of execution between tasks
1348 * scheduled concurrently.
1350 * The task will be run with the DEFAULT priority.
1352 * @param task main function of the task
1353 * @param task_cls closure of @a task
1354 * @return unique task identifier for the job
1355 * only valid until @a task is started!
1357 struct GNUNET_SCHEDULER_Task *
1358 GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_TaskCallback task,
1361 return GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_ZERO,
1368 * Schedule a new task to be run on shutdown, that is when a CTRL-C
1369 * signal is received, or when #GNUNET_SCHEDULER_shutdown() is being
1372 * @param task main function of the task
1373 * @param task_cls closure of @a task
1374 * @return unique task identifier for the job
1375 * only valid until @a task is started!
1377 struct GNUNET_SCHEDULER_Task *
1378 GNUNET_SCHEDULER_add_shutdown (GNUNET_SCHEDULER_TaskCallback task,
1381 struct GNUNET_SCHEDULER_Task *t;
1383 GNUNET_assert (NULL != active_task);
1384 GNUNET_assert (NULL != task);
1385 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1387 t->callback_cls = task_cls;
1391 t->start_time = GNUNET_TIME_absolute_get ();
1393 t->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
1394 t->priority = GNUNET_SCHEDULER_PRIORITY_SHUTDOWN;
1395 t->on_shutdown = GNUNET_YES;
1396 t->lifeness = GNUNET_YES;
1397 GNUNET_CONTAINER_DLL_insert (shutdown_head,
1400 LOG (GNUNET_ERROR_TYPE_DEBUG,
1401 "Adding task: %p\n",
1409 * Schedule a new task to be run as soon as possible with the
1410 * (transitive) ignore-shutdown flag either explicitly set or
1411 * explicitly enabled. This task (and all tasks created from it,
1412 * other than by another call to this function) will either count or
1413 * not count for the "lifeness" of the process. This API is only
1414 * useful in a few special cases.
1416 * @param lifeness #GNUNET_YES if the task counts for lifeness, #GNUNET_NO if not.
1417 * @param task main function of the task
1418 * @param task_cls closure of @a task
1419 * @return unique task identifier for the job
1420 * only valid until @a task is started!
1422 struct GNUNET_SCHEDULER_Task *
1423 GNUNET_SCHEDULER_add_now_with_lifeness (int lifeness,
1424 GNUNET_SCHEDULER_TaskCallback task,
1427 struct GNUNET_SCHEDULER_Task *ret;
1429 ret = GNUNET_SCHEDULER_add_now (task, task_cls);
1430 ret->lifeness = lifeness;
1436 * Schedule a new task to be run with a specified delay or when any of
1437 * the specified file descriptor sets is ready. The delay can be used
1438 * as a timeout on the socket(s) being ready. The task will be
1439 * scheduled for execution once either the delay has expired or any of
1440 * the socket operations is ready. This is the most general
1441 * function of the "add" family. Note that the "prerequisite_task"
1442 * must be satisfied in addition to any of the other conditions. In
1443 * other words, the task will be started when
1445 * (prerequisite-run)
1451 * @param delay how long should we wait?
1452 * @param priority priority to use
1453 * @param rfd file descriptor we want to read (can be -1)
1454 * @param wfd file descriptors we want to write (can be -1)
1455 * @param task main function of the task
1456 * @param task_cls closure of @a task
1457 * @return unique task identifier for the job
1458 * only valid until @a task is started!
1461 static struct GNUNET_SCHEDULER_Task *
1462 add_without_sets (struct GNUNET_TIME_Relative delay,
1463 enum GNUNET_SCHEDULER_Priority priority,
1464 const struct GNUNET_NETWORK_Handle *read_nh,
1465 const struct GNUNET_NETWORK_Handle *write_nh,
1466 const struct GNUNET_DISK_FileHandle *read_fh,
1467 const struct GNUNET_DISK_FileHandle *write_fh,
1470 GNUNET_SCHEDULER_TaskCallback task,
1473 struct GNUNET_SCHEDULER_Task *t;
1475 GNUNET_assert (NULL != active_task);
1476 GNUNET_assert (NULL != task);
1477 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1478 initFdInfo (t, read_nh, write_nh, read_fh, write_fh);
1480 t->callback_cls = task_cls;
1484 int flags = fcntl (rfd, F_GETFD);
1486 if ((flags == -1) && (errno == EBADF))
1488 LOG (GNUNET_ERROR_TYPE_ERROR,
1489 "Got invalid file descriptor %d!\n",
1497 int flags = fcntl (wfd, F_GETFD);
1499 if (flags == -1 && errno == EBADF)
1501 LOG (GNUNET_ERROR_TYPE_ERROR,
1502 "Got invalid file descriptor %d!\n",
1511 t->start_time = GNUNET_TIME_absolute_get ();
1513 t->timeout = GNUNET_TIME_relative_to_absolute (delay);
1514 t->priority = check_priority ((priority == GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority : priority);
1515 t->lifeness = current_lifeness;
1516 GNUNET_CONTAINER_DLL_insert (pending_head,
1519 scheduler_multi_function_call(t, scheduler_driver->add);
1520 max_priority_added = GNUNET_MAX (max_priority_added,
1522 LOG (GNUNET_ERROR_TYPE_DEBUG,
1532 * Schedule a new task to be run with a specified delay or when the
1533 * specified file descriptor is ready for reading. The delay can be
1534 * used as a timeout on the socket being ready. The task will be
1535 * scheduled for execution once either the delay has expired or the
1536 * socket operation is ready. It will be run with the DEFAULT priority.
1538 * @param delay when should this operation time out?
1539 * @param rfd read file-descriptor
1540 * @param task main function of the task
1541 * @param task_cls closure of @a task
1542 * @return unique task identifier for the job
1543 * only valid until @a task is started!
1545 struct GNUNET_SCHEDULER_Task *
1546 GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay,
1547 struct GNUNET_NETWORK_Handle *rfd,
1548 GNUNET_SCHEDULER_TaskCallback task,
1551 return GNUNET_SCHEDULER_add_read_net_with_priority (delay,
1552 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1553 rfd, task, task_cls);
1558 * Schedule a new task to be run with a specified priority and to be
1559 * run after the specified delay or when the specified file descriptor
1560 * is ready for reading. The delay can be used as a timeout on the
1561 * socket being ready. The task will be scheduled for execution once
1562 * either the delay has expired or the socket operation is ready. It
1563 * will be run with the DEFAULT priority.
1565 * @param delay when should this operation time out?
1566 * @param priority priority to use for the task
1567 * @param rfd read file-descriptor
1568 * @param task main function of the task
1569 * @param task_cls closure of @a task
1570 * @return unique task identifier for the job
1571 * only valid until @a task is started!
1573 struct GNUNET_SCHEDULER_Task *
1574 GNUNET_SCHEDULER_add_read_net_with_priority (struct GNUNET_TIME_Relative delay,
1575 enum GNUNET_SCHEDULER_Priority priority,
1576 struct GNUNET_NETWORK_Handle *rfd,
1577 GNUNET_SCHEDULER_TaskCallback task,
1580 return GNUNET_SCHEDULER_add_net_with_priority (delay, priority,
1589 * Schedule a new task to be run with a specified delay or when the
1590 * specified file descriptor is ready for writing. The delay can be
1591 * used as a timeout on the socket being ready. The task will be
1592 * scheduled for execution once either the delay has expired or the
1593 * socket operation is ready. It will be run with the priority of
1596 * @param delay when should this operation time out?
1597 * @param wfd write file-descriptor
1598 * @param task main function of the task
1599 * @param task_cls closure of @a task
1600 * @return unique task identifier for the job
1601 * only valid until @a task is started!
1603 struct GNUNET_SCHEDULER_Task *
1604 GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay,
1605 struct GNUNET_NETWORK_Handle *wfd,
1606 GNUNET_SCHEDULER_TaskCallback task,
1609 return GNUNET_SCHEDULER_add_net_with_priority (delay,
1610 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1612 GNUNET_NO, GNUNET_YES,
1617 * Schedule a new task to be run with a specified delay or when the
1618 * specified file descriptor is ready. The delay can be
1619 * used as a timeout on the socket being ready. The task will be
1620 * scheduled for execution once either the delay has expired or the
1621 * socket operation is ready.
1623 * @param delay when should this operation time out?
1624 * @param priority priority of the task
1625 * @param fd file-descriptor
1626 * @param on_read whether to poll the file-descriptor for readability
1627 * @param on_write whether to poll the file-descriptor for writability
1628 * @param task main function of the task
1629 * @param task_cls closure of task
1630 * @return unique task identifier for the job
1631 * only valid until "task" is started!
1633 struct GNUNET_SCHEDULER_Task *
1634 GNUNET_SCHEDULER_add_net_with_priority (struct GNUNET_TIME_Relative delay,
1635 enum GNUNET_SCHEDULER_Priority priority,
1636 struct GNUNET_NETWORK_Handle *fd,
1639 GNUNET_SCHEDULER_TaskCallback task,
1643 struct GNUNET_NETWORK_FDSet *s;
1644 struct GNUNET_SCHEDULER_Task * ret;
1646 GNUNET_assert (NULL != fd);
1647 s = GNUNET_NETWORK_fdset_create ();
1648 GNUNET_NETWORK_fdset_set (s, fd);
1649 ret = GNUNET_SCHEDULER_add_select (
1652 on_write ? s : NULL,
1654 GNUNET_NETWORK_fdset_destroy (s);
1657 GNUNET_assert (on_read || on_write);
1658 GNUNET_assert (GNUNET_NETWORK_get_fd (fd) >= 0);
1659 return add_without_sets (delay, priority,
1660 on_read ? fd : NULL,
1661 on_write ? fd : NULL,
1670 * Schedule a new task to be run with a specified delay or when the
1671 * specified file descriptor is ready for reading. The delay can be
1672 * used as a timeout on the socket being ready. The task will be
1673 * scheduled for execution once either the delay has expired or the
1674 * socket operation is ready. It will be run with the DEFAULT priority.
1676 * @param delay when should this operation time out?
1677 * @param rfd read file-descriptor
1678 * @param task main function of the task
1679 * @param task_cls closure of @a task
1680 * @return unique task identifier for the job
1681 * only valid until @a task is started!
1683 struct GNUNET_SCHEDULER_Task *
1684 GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay,
1685 const struct GNUNET_DISK_FileHandle *rfd,
1686 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1688 return GNUNET_SCHEDULER_add_file_with_priority (
1689 delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1690 rfd, GNUNET_YES, GNUNET_NO,
1696 * Schedule a new task to be run with a specified delay or when the
1697 * specified file descriptor is ready for writing. The delay can be
1698 * used as a timeout on the socket being ready. The task will be
1699 * scheduled for execution once either the delay has expired or the
1700 * socket operation is ready. It will be run with the DEFAULT priority.
1702 * @param delay when should this operation time out?
1703 * @param wfd write file-descriptor
1704 * @param task main function of the task
1705 * @param task_cls closure of @a task
1706 * @return unique task identifier for the job
1707 * only valid until @a task is started!
1709 struct GNUNET_SCHEDULER_Task *
1710 GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay,
1711 const struct GNUNET_DISK_FileHandle *wfd,
1712 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1714 return GNUNET_SCHEDULER_add_file_with_priority (
1715 delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1716 wfd, GNUNET_NO, GNUNET_YES,
1722 * Schedule a new task to be run with a specified delay or when the
1723 * specified file descriptor is ready. The delay can be
1724 * used as a timeout on the socket being ready. The task will be
1725 * scheduled for execution once either the delay has expired or the
1726 * socket operation is ready.
1728 * @param delay when should this operation time out?
1729 * @param priority priority of the task
1730 * @param fd file-descriptor
1731 * @param on_read whether to poll the file-descriptor for readability
1732 * @param on_write whether to poll the file-descriptor for writability
1733 * @param task main function of the task
1734 * @param task_cls closure of @a task
1735 * @return unique task identifier for the job
1736 * only valid until @a task is started!
1738 struct GNUNET_SCHEDULER_Task *
1739 GNUNET_SCHEDULER_add_file_with_priority (struct GNUNET_TIME_Relative delay,
1740 enum GNUNET_SCHEDULER_Priority priority,
1741 const struct GNUNET_DISK_FileHandle *fd,
1742 int on_read, int on_write,
1743 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1746 struct GNUNET_NETWORK_FDSet *s;
1747 struct GNUNET_SCHEDULER_Task * ret;
1749 GNUNET_assert (NULL != fd);
1750 s = GNUNET_NETWORK_fdset_create ();
1751 GNUNET_NETWORK_fdset_handle_set (s, fd);
1752 ret = GNUNET_SCHEDULER_add_select (
1755 on_write ? s : NULL,
1757 GNUNET_NETWORK_fdset_destroy (s);
1760 GNUNET_assert (on_read || on_write);
1761 GNUNET_assert(fd->fd >= 0);
1762 return add_without_sets (delay, priority,
1765 on_read ? fd : NULL,
1766 on_write ? fd : NULL,
1773 * Schedule a new task to be run with a specified delay or when any of
1774 * the specified file descriptor sets is ready. The delay can be used
1775 * as a timeout on the socket(s) being ready. The task will be
1776 * scheduled for execution once either the delay has expired or any of
1777 * the socket operations is ready. This is the most general
1778 * function of the "add" family. Note that the "prerequisite_task"
1779 * must be satisfied in addition to any of the other conditions. In
1780 * other words, the task will be started when
1782 * (prerequisite-run)
1785 * || any-ws-ready) )
1788 * @param prio how important is this task?
1789 * @param delay how long should we wait?
1790 * @param rs set of file descriptors we want to read (can be NULL)
1791 * @param ws set of file descriptors we want to write (can be NULL)
1792 * @param task main function of the task
1793 * @param task_cls closure of @a task
1794 * @return unique task identifier for the job
1795 * only valid until @a task is started!
1797 struct GNUNET_SCHEDULER_Task *
1798 GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio,
1799 struct GNUNET_TIME_Relative delay,
1800 const struct GNUNET_NETWORK_FDSet *rs,
1801 const struct GNUNET_NETWORK_FDSet *ws,
1802 GNUNET_SCHEDULER_TaskCallback task,
1805 struct GNUNET_SCHEDULER_Task *t;
1807 if ( (NULL == rs) &&
1809 return GNUNET_SCHEDULER_add_delayed_with_priority (delay,
1813 GNUNET_assert (NULL != active_task);
1814 GNUNET_assert (NULL != task);
1815 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1817 t->callback_cls = task_cls;
1822 t->read_set = GNUNET_NETWORK_fdset_create ();
1823 GNUNET_NETWORK_fdset_copy (t->read_set, rs);
1827 t->write_set = GNUNET_NETWORK_fdset_create ();
1828 GNUNET_NETWORK_fdset_copy (t->write_set, ws);
1831 t->start_time = GNUNET_TIME_absolute_get ();
1833 t->timeout = GNUNET_TIME_relative_to_absolute (delay);
1835 check_priority ((prio ==
1836 GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority :
1838 t->lifeness = current_lifeness;
1839 GNUNET_CONTAINER_DLL_insert (pending_head,
1842 scheduler_multi_function_call(t, scheduler_driver->add);
1843 max_priority_added = GNUNET_MAX (max_priority_added,
1845 LOG (GNUNET_ERROR_TYPE_DEBUG,
1854 * Function used by event-loop implementations to signal the scheduler
1855 * that a particular @a task is ready due to an event of type @a et.
1857 * This function will then queue the task to notify the application
1858 * that the task is ready (with the respective priority).
1860 * @param task the task that is ready, NULL for wake up calls
1861 * @param et information about why the task is ready
1864 GNUNET_SCHEDULER_task_ready (struct GNUNET_SCHEDULER_Task *task,
1865 enum GNUNET_SCHEDULER_EventType et)
1867 enum GNUNET_SCHEDULER_Reason reason;
1868 struct GNUNET_TIME_Absolute now;
1870 now = GNUNET_TIME_absolute_get ();
1871 reason = task->reason;
1872 if (now.abs_value_us >= task->timeout.abs_value_us)
1873 reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
1874 if ( (0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
1875 (0 != (GNUNET_SCHEDULER_ET_IN & et)) )
1876 reason |= GNUNET_SCHEDULER_REASON_READ_READY;
1877 if ( (0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
1878 (0 != (GNUNET_SCHEDULER_ET_OUT & et)) )
1879 reason |= GNUNET_SCHEDULER_REASON_WRITE_READY;
1880 reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE;
1881 task->reason = reason;
1882 task->fds = &task->fdx;
1885 queue_ready_task (task);
1890 * Function called by the driver to tell the scheduler to run some of
1891 * the tasks that are ready. This function may return even though
1892 * there are tasks left to run just to give other tasks a chance as
1893 * well. If we return #GNUNET_YES, the driver should call this
1894 * function again as soon as possible, while if we return #GNUNET_NO
1895 * it must block until the operating system has more work as the
1896 * scheduler has no more work to do right now.
1898 * @param sh scheduler handle that was given to the `loop`
1899 * @return #GNUNET_OK if there are more tasks that are ready,
1900 * and thus we would like to run more (yield to avoid
1901 * blocking other activities for too long)
1902 * #GNUNET_NO if we are done running tasks (yield to block)
1903 * #GNUNET_SYSERR on error
1906 GNUNET_SCHEDULER_run_from_driver (struct GNUNET_SCHEDULER_Handle *sh)
1908 enum GNUNET_SCHEDULER_Priority p;
1909 struct GNUNET_SCHEDULER_Task *pos;
1910 struct GNUNET_TIME_Absolute now;
1912 /* check for tasks that reached the timeout! */
1913 now = GNUNET_TIME_absolute_get ();
1914 while (NULL != (pos = pending_timeout_head))
1916 if (now.abs_value_us >= pos->timeout.abs_value_us)
1917 pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
1918 if (0 == pos->reason)
1920 GNUNET_CONTAINER_DLL_remove (pending_timeout_head,
1921 pending_timeout_tail,
1923 scheduler_driver->set_wakeup(scheduler_driver->cls,pending_timeout_head->timeout);
1924 if (pending_timeout_last == pos)
1925 pending_timeout_last = NULL;
1926 queue_ready_task (pos);
1929 if (0 == ready_count)
1932 /* find out which task priority level we are going to
1933 process this time */
1934 max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
1935 GNUNET_assert (NULL == ready_head[GNUNET_SCHEDULER_PRIORITY_KEEP]);
1936 /* yes, p>0 is correct, 0 is "KEEP" which should
1937 * always be an empty queue (see assertion)! */
1938 for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)
1940 pos = ready_head[p];
1944 GNUNET_assert (NULL != pos); /* ready_count wrong? */
1946 /* process all tasks at this priority level, then yield */
1947 while (NULL != (pos = ready_head[p]))
1949 GNUNET_CONTAINER_DLL_remove (ready_head[p],
1953 current_priority = pos->priority;
1954 current_lifeness = pos->lifeness;
1957 if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value_us >
1958 DELAY_THRESHOLD.rel_value_us)
1960 LOG (GNUNET_ERROR_TYPE_DEBUG,
1961 "Task %p took %s to be scheduled\n",
1963 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (pos->start_time),
1967 tc.reason = pos->reason;
1968 GNUNET_NETWORK_fdset_zero (sh->rs);
1969 GNUNET_NETWORK_fdset_zero (sh->ws);
1970 tc.fds_len = pos->fds_len;
1972 tc.read_ready = (NULL == pos->read_set) ? sh->rs : pos->read_set;
1973 if ( (-1 != pos->read_fd) &&
1974 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY)) )
1975 GNUNET_NETWORK_fdset_set_native (sh->rs,
1977 tc.write_ready = (NULL == pos->write_set) ? sh->ws : pos->write_set;
1978 if ((-1 != pos->write_fd) &&
1979 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)))
1980 GNUNET_NETWORK_fdset_set_native (sh->ws,
1982 LOG (GNUNET_ERROR_TYPE_DEBUG,
1983 "Running task: %p\n",
1985 pos->callback (pos->callback_cls);
1987 dump_backtrace (pos);
1991 if (0 == ready_count)
1998 * Initialize and run scheduler. This function will return when all
1999 * tasks have completed. On systems with signals, receiving a SIGTERM
2000 * (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown
2001 * to be run after the active task is complete. As a result, SIGTERM
2002 * causes all shutdown tasks to be scheduled with reason
2003 * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added
2004 * afterwards will execute normally!). Note that any particular
2005 * signal will only shut down one scheduler; applications should
2006 * always only create a single scheduler.
2008 * @param driver drive to use for the event loop
2009 * @param task task to run first (and immediately)
2010 * @param task_cls closure of @a task
2011 * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
2014 GNUNET_SCHEDULER_run_with_driver (const struct GNUNET_SCHEDULER_Driver *driver,
2015 GNUNET_SCHEDULER_TaskCallback task,
2019 struct GNUNET_SCHEDULER_Handle sh;
2020 struct GNUNET_SIGNAL_Context *shc_int;
2021 struct GNUNET_SIGNAL_Context *shc_term;
2022 #if (SIGTERM != GNUNET_TERM_SIG)
2023 struct GNUNET_SIGNAL_Context *shc_gterm;
2026 struct GNUNET_SIGNAL_Context *shc_quit;
2027 struct GNUNET_SIGNAL_Context *shc_hup;
2028 struct GNUNET_SIGNAL_Context *shc_pipe;
2030 struct GNUNET_SCHEDULER_Task tsk;
2031 const struct GNUNET_DISK_FileHandle *pr;
2032 scheduler_driver = driver;
2034 /* general set-up */
2035 GNUNET_assert (NULL == active_task);
2036 GNUNET_assert (NULL == shutdown_pipe_handle);
2037 shutdown_pipe_handle = GNUNET_DISK_pipe (GNUNET_NO,
2041 GNUNET_assert (NULL != shutdown_pipe_handle);
2042 pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle,
2043 GNUNET_DISK_PIPE_END_READ);
2044 GNUNET_assert (NULL != pr);
2047 /* install signal handlers */
2048 LOG (GNUNET_ERROR_TYPE_DEBUG,
2049 "Registering signal handlers\n");
2050 shc_int = GNUNET_SIGNAL_handler_install (SIGINT,
2051 &sighandler_shutdown);
2052 shc_term = GNUNET_SIGNAL_handler_install (SIGTERM,
2053 &sighandler_shutdown);
2054 #if (SIGTERM != GNUNET_TERM_SIG)
2055 shc_gterm = GNUNET_SIGNAL_handler_install (GNUNET_TERM_SIG,
2056 &sighandler_shutdown);
2059 shc_pipe = GNUNET_SIGNAL_handler_install (SIGPIPE,
2061 shc_quit = GNUNET_SIGNAL_handler_install (SIGQUIT,
2062 &sighandler_shutdown);
2063 shc_hup = GNUNET_SIGNAL_handler_install (SIGHUP,
2064 &sighandler_shutdown);
2067 /* Setup initial tasks */
2068 current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT;
2069 current_lifeness = GNUNET_YES;
2075 GNUNET_SCHEDULER_add_with_reason_and_priority (task,
2077 GNUNET_SCHEDULER_REASON_STARTUP,
2078 GNUNET_SCHEDULER_PRIORITY_DEFAULT);
2079 GNUNET_SCHEDULER_add_now_with_lifeness (GNUNET_NO,
2080 &GNUNET_OS_install_parent_control_handler,
2083 driver->set_wakeup (driver->cls,
2084 GNUNET_TIME_absolute_get ());
2086 /* begin main event loop */
2087 sh.rs = GNUNET_NETWORK_fdset_create ();
2088 sh.ws = GNUNET_NETWORK_fdset_create ();
2089 GNUNET_NETWORK_fdset_handle_set (sh.rs, pr);
2091 ret = driver->loop (driver->cls,
2093 GNUNET_NETWORK_fdset_destroy (sh.rs);
2094 GNUNET_NETWORK_fdset_destroy (sh.ws);
2096 /* uninstall signal handlers */
2097 GNUNET_SIGNAL_handler_uninstall (shc_int);
2098 GNUNET_SIGNAL_handler_uninstall (shc_term);
2099 #if (SIGTERM != GNUNET_TERM_SIG)
2100 GNUNET_SIGNAL_handler_uninstall (shc_gterm);
2103 GNUNET_SIGNAL_handler_uninstall (shc_pipe);
2104 GNUNET_SIGNAL_handler_uninstall (shc_quit);
2105 GNUNET_SIGNAL_handler_uninstall (shc_hup);
2107 GNUNET_DISK_pipe_close (shutdown_pipe_handle);
2108 shutdown_pipe_handle = NULL;
2113 select_add(void *cls,
2114 struct GNUNET_SCHEDULER_Task *task,
2115 struct GNUNET_SCHEDULER_FdInfo *fdi)
2122 select_del(void *cls,
2123 struct GNUNET_SCHEDULER_Task *task,
2124 struct GNUNET_SCHEDULER_FdInfo *fdi)
2131 select_loop(void *cls,
2132 struct GNUNET_SCHEDULER_Handle *sh)
2134 return while_live(sh->rs, sh->ws);
2139 select_set_wakeup(void *cls,
2140 struct GNUNET_TIME_Absolute dt)
2147 * Obtain the driver for using select() as the event loop.
2149 * @return NULL on error
2151 const struct GNUNET_SCHEDULER_Driver *
2152 GNUNET_SCHEDULER_driver_select ()
2155 struct GNUNET_SCHEDULER_Driver *select_driver;
2157 select_driver = GNUNET_new (struct GNUNET_SCHEDULER_Driver);
2159 select_driver->loop = &select_loop;
2160 select_driver->add = &select_add;
2161 select_driver->del = &select_del;
2162 select_driver->set_wakeup = &select_set_wakeup;
2165 return select_driver;
2169 /* end of scheduler.c */